Nixyri/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2024-11-16 17:15:37 +00:00
Code Issues Packages Projects Releases Wiki Activity
dbbe709dc7
zig/lib/std/os.zig
Lee Cannon dbbe709dc7 use else in err switch
2020-11-18 15:37:44 +01:00

5700 lines
219 KiB
Zig
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// SPDX-License-Identifier: MIT
// Copyright (c) 2015-2020 Zig Contributors
// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
// The MIT license requires this copyright notice to be included in all copies
// and substantial portions of the software.
// This file contains thin wrappers around OS-specific APIs, with these
// specific goals in mind:
// * Convert "errno"-style error codes into Zig errors.
// * When null-terminated byte buffers are required, provide APIs which accept
// slices as well as APIs which accept null-terminated byte buffers. Same goes
// for UTF-16LE encoding.
// * Where operating systems share APIs, e.g. POSIX, these thin wrappers provide
// cross platform abstracting.
// * When there exists a corresponding libc function and linking libc, the libc
// implementation is used. Exceptions are made for known buggy areas of libc.
// On Linux libc can be side-stepped by using `std.os.linux` directly.
// * For Windows, this file represents the API that libc would provide for
// Windows. For thin wrappers around Windows-specific APIs, see `std.os.windows`.
// Note: The Zig standard library does not support POSIX thread cancellation, and
// in general EINTR is handled by trying again.
const root = @import("root");
const std = @import("std.zig");
const builtin = @import("builtin");
const assert = std.debug.assert;
const math = std.math;
const mem = std.mem;
const elf = std.elf;
const dl = @import("dynamic_library.zig");
const MAX_PATH_BYTES = std.fs.MAX_PATH_BYTES;
pub const darwin = @import("os/darwin.zig");
pub const dragonfly = @import("os/dragonfly.zig");
pub const freebsd = @import("os/freebsd.zig");
pub const netbsd = @import("os/netbsd.zig");
pub const openbsd = @import("os/openbsd.zig");
pub const linux = @import("os/linux.zig");
pub const uefi = @import("os/uefi.zig");
pub const wasi = @import("os/wasi.zig");
pub const windows = @import("os/windows.zig");
comptime {
assert(@import("std") == std); // std lib tests require --override-lib-dir
}
test "" {
_ = darwin;
_ = freebsd;
_ = linux;
_ = netbsd;
_ = openbsd;
_ = uefi;
_ = wasi;
_ = windows;
_ = @import("os/test.zig");
}
/// Applications can override the `system` API layer in their root source file.
/// Otherwise, when linking libc, this is the C API.
/// When not linking libc, it is the OS-specific system interface.
pub const system = if (@hasDecl(root, "os") and root.os != @This())
root.os.system
else if (builtin.link_libc)
std.c
else switch (builtin.os.tag) {
.macos, .ios, .watchos, .tvos => darwin,
.freebsd => freebsd,
.linux => linux,
.netbsd => netbsd,
.openbsd => openbsd,
.dragonfly => dragonfly,
.wasi => wasi,
.windows => windows,
else => struct {},
};
pub usingnamespace @import("os/bits.zig");
pub const socket_t = if (builtin.os.tag == .windows) windows.ws2_32.SOCKET else fd_t;
/// See also `getenv`. Populated by startup code before main().
/// TODO this is a footgun because the value will be undefined when using `zig build-lib`.
/// https://github.com/ziglang/zig/issues/4524
pub var environ: [][*:0]u8 = undefined;
/// Populated by startup code before main().
/// Not available on Windows. See `std.process.args`
/// for obtaining the process arguments.
pub var argv: [][*:0]u8 = undefined;
/// To obtain errno, call this function with the return value of the
/// system function call. For some systems this will obtain the value directly
/// from the return code; for others it will use a thread-local errno variable.
/// Therefore, this function only returns a well-defined value when it is called
/// directly after the system function call which one wants to learn the errno
/// value of.
pub const errno = system.getErrno;
/// Closes the file descriptor.
/// This function is not capable of returning any indication of failure. An
/// application which wants to ensure writes have succeeded before closing
/// must call `fsync` before `close`.
/// Note: The Zig standard library does not support POSIX thread cancellation.
pub fn close(fd: fd_t) void {
if (builtin.os.tag == .windows) {
return windows.CloseHandle(fd);
}
if (builtin.os.tag == .wasi) {
_ = wasi.fd_close(fd);
return;
}
if (comptime std.Target.current.isDarwin()) {
// This avoids the EINTR problem.
switch (darwin.getErrno(darwin.@"close$NOCANCEL"(fd))) {
EBADF => unreachable, // Always a race condition.
else => return,
}
}
switch (errno(system.close(fd))) {
EBADF => unreachable, // Always a race condition.
EINTR => return, // This is still a success. See https://github.com/ziglang/zig/issues/2425
else => return,
}
}
pub const GetRandomError = OpenError;
/// Obtain a series of random bytes. These bytes can be used to seed user-space
/// random number generators or for cryptographic purposes.
/// When linking against libc, this calls the
/// appropriate OS-specific library call. Otherwise it uses the zig standard
/// library implementation.
pub fn getrandom(buffer: []u8) GetRandomError!void {
if (builtin.os.tag == .windows) {
return windows.RtlGenRandom(buffer);
}
if (builtin.os.tag == .linux or builtin.os.tag == .freebsd) {
var buf = buffer;
const use_c = builtin.os.tag != .linux or
std.c.versionCheck(builtin.Version{ .major = 2, .minor = 25, .patch = 0 }).ok;
while (buf.len != 0) {
var err: u16 = undefined;
const num_read = if (use_c) blk: {
const rc = std.c.getrandom(buf.ptr, buf.len, 0);
err = std.c.getErrno(rc);
break :blk @bitCast(usize, rc);
} else blk: {
const rc = linux.getrandom(buf.ptr, buf.len, 0);
err = linux.getErrno(rc);
break :blk rc;
};
switch (err) {
0 => buf = buf[num_read..],
EINVAL => unreachable,
EFAULT => unreachable,
EINTR => continue,
ENOSYS => return getRandomBytesDevURandom(buf),
else => return unexpectedErrno(err),
}
}
return;
}
switch (builtin.os.tag) {
.netbsd, .openbsd, .macos, .ios, .tvos, .watchos => {
system.arc4random_buf(buffer.ptr, buffer.len);
return;
},
.wasi => switch (wasi.random_get(buffer.ptr, buffer.len)) {
0 => return,
else => |err| return unexpectedErrno(err),
},
else => return getRandomBytesDevURandom(buffer),
}
}
fn getRandomBytesDevURandom(buf: []u8) !void {
const fd = try openZ("/dev/urandom", O_RDONLY | O_CLOEXEC, 0);
defer close(fd);
const st = try fstat(fd);
if (!S_ISCHR(st.mode)) {
return error.NoDevice;
}
const file = std.fs.File{
.handle = fd,
.capable_io_mode = .blocking,
.intended_io_mode = .blocking,
};
const stream = file.inStream();
stream.readNoEof(buf) catch return error.Unexpected;
}
/// Causes abnormal process termination.
/// If linking against libc, this calls the abort() libc function. Otherwise
/// it raises SIGABRT followed by SIGKILL and finally lo
pub fn abort() noreturn {
@setCold(true);
// MSVCRT abort() sometimes opens a popup window which is undesirable, so
// even when linking libc on Windows we use our own abort implementation.
// See https://github.com/ziglang/zig/issues/2071 for more details.
if (builtin.os.tag == .windows) {
if (builtin.mode == .Debug) {
@breakpoint();
}
windows.kernel32.ExitProcess(3);
}
if (!builtin.link_libc and builtin.os.tag == .linux) {
raise(SIGABRT) catch {};
// TODO the rest of the implementation of abort() from musl libc here
raise(SIGKILL) catch {};
exit(127);
}
if (builtin.os.tag == .uefi) {
exit(0); // TODO choose appropriate exit code
}
if (builtin.os.tag == .wasi) {
@breakpoint();
exit(1);
}
system.abort();
}
pub const RaiseError = UnexpectedError;
pub fn raise(sig: u8) RaiseError!void {
if (builtin.link_libc) {
switch (errno(system.raise(sig))) {
0 => return,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .linux) {
var set: linux.sigset_t = undefined;
// block application signals
_ = linux.sigprocmask(SIG_BLOCK, &linux.app_mask, &set);
const tid = linux.gettid();
const rc = linux.tkill(tid, sig);
// restore signal mask
_ = linux.sigprocmask(SIG_SETMASK, &set, null);
switch (errno(rc)) {
0 => return,
else => |err| return unexpectedErrno(err),
}
}
@compileError("std.os.raise unimplemented for this target");
}
pub const KillError = error{PermissionDenied} || UnexpectedError;
pub fn kill(pid: pid_t, sig: u8) KillError!void {
switch (errno(system.kill(pid, sig))) {
0 => return,
EINVAL => unreachable, // invalid signal
EPERM => return error.PermissionDenied,
ESRCH => unreachable, // always a race condition
else => |err| return unexpectedErrno(err),
}
}
/// Exits the program cleanly with the specified status code.
pub fn exit(status: u8) noreturn {
if (builtin.link_libc) {
system.exit(status);
}
if (builtin.os.tag == .windows) {
windows.kernel32.ExitProcess(status);
}
if (builtin.os.tag == .wasi) {
wasi.proc_exit(status);
}
if (builtin.os.tag == .linux and !builtin.single_threaded) {
linux.exit_group(status);
}
if (builtin.os.tag == .uefi) {
// exit() is only avaliable if exitBootServices() has not been called yet.
// This call to exit should not fail, so we don't care about its return value.
if (uefi.system_table.boot_services) |bs| {
_ = bs.exit(uefi.handle, @intToEnum(uefi.Status, status), 0, null);
}
// If we can't exit, reboot the system instead.
uefi.system_table.runtime_services.resetSystem(uefi.tables.ResetType.ResetCold, @intToEnum(uefi.Status, status), 0, null);
}
system.exit(status);
}
pub const ReadError = error{
InputOutput,
SystemResources,
IsDir,
OperationAborted,
BrokenPipe,
ConnectionResetByPeer,
ConnectionTimedOut,
NotOpenForReading,
/// This error occurs when no global event loop is configured,
/// and reading from the file descriptor would block.
WouldBlock,
/// In WASI, this error occurs when the file descriptor does
/// not hold the required rights to read from it.
AccessDenied,
} || UnexpectedError;
/// Returns the number of bytes that were read, which can be less than
/// buf.len. If 0 bytes were read, that means EOF.
/// If `fd` is opened in non blocking mode, the function will return error.WouldBlock
/// when EAGAIN is received.
///
/// Linux has a limit on how many bytes may be transferred in one `read` call, which is `0x7ffff000`
/// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as
/// well as stuffing the errno codes into the last `4096` values. This is noted on the `read` man page.
/// The limit on Darwin is `0x7fffffff`, trying to read more than that returns EINVAL.
/// For POSIX the limit is `math.maxInt(isize)`.
pub fn read(fd: fd_t, buf: []u8) ReadError!usize {
if (builtin.os.tag == .windows) {
return windows.ReadFile(fd, buf, null, std.io.default_mode);
}
if (builtin.os.tag == .wasi and !builtin.link_libc) {
const iovs = [1]iovec{iovec{
.iov_base = buf.ptr,
.iov_len = buf.len,
}};
var nread: usize = undefined;
switch (wasi.fd_read(fd, &iovs, iovs.len, &nread)) {
wasi.ESUCCESS => return nread,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForReading, // Can be a race condition.
wasi.EIO => return error.InputOutput,
wasi.EISDIR => return error.IsDir,
wasi.ENOBUFS => return error.SystemResources,
wasi.ENOMEM => return error.SystemResources,
wasi.ECONNRESET => return error.ConnectionResetByPeer,
wasi.ETIMEDOUT => return error.ConnectionTimedOut,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
// Prevents EINVAL.
const max_count = switch (std.Target.current.os.tag) {
.linux => 0x7ffff000,
.macos, .ios, .watchos, .tvos => math.maxInt(i32),
else => math.maxInt(isize),
};
const adjusted_len = math.min(max_count, buf.len);
while (true) {
const rc = system.read(fd, buf.ptr, adjusted_len);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForReading, // Can be a race condition.
EIO => return error.InputOutput,
EISDIR => return error.IsDir,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
ECONNRESET => return error.ConnectionResetByPeer,
ETIMEDOUT => return error.ConnectionTimedOut,
else => |err| return unexpectedErrno(err),
}
}
return index;
}
/// Number of bytes read is returned. Upon reading end-of-file, zero is returned.
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
///
/// This operation is non-atomic on the following systems:
/// * Windows
/// On these systems, the read races with concurrent writes to the same file descriptor.
pub fn readv(fd: fd_t, iov: []const iovec) ReadError!usize {
if (std.Target.current.os.tag == .windows) {
// TODO improve this to use ReadFileScatter
if (iov.len == 0) return @as(usize, 0);
const first = iov[0];
return read(fd, first.iov_base[0..first.iov_len]);
}
if (builtin.os.tag == .wasi) {
var nread: usize = undefined;
switch (wasi.fd_read(fd, iov.ptr, iov.len, &nread)) {
wasi.ESUCCESS => return nread,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable, // currently not support in WASI
wasi.EBADF => return error.NotOpenForReading, // can be a race condition
wasi.EIO => return error.InputOutput,
wasi.EISDIR => return error.IsDir,
wasi.ENOBUFS => return error.SystemResources,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const iov_count = math.cast(u31, iov.len) catch math.maxInt(u31);
while (true) {
// TODO handle the case when iov_len is too large and get rid of this @intCast
const rc = system.readv(fd, iov.ptr, iov_count);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForReading, // can be a race condition
EIO => return error.InputOutput,
EISDIR => return error.IsDir,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
}
pub const PReadError = ReadError || error{Unseekable};
/// Number of bytes read is returned. Upon reading end-of-file, zero is returned.
///
/// Retries when interrupted by a signal.
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
pub fn pread(fd: fd_t, buf: []u8, offset: u64) PReadError!usize {
if (builtin.os.tag == .windows) {
return windows.ReadFile(fd, buf, offset, std.io.default_mode);
}
if (builtin.os.tag == .wasi) {
const iovs = [1]iovec{iovec{
.iov_base = buf.ptr,
.iov_len = buf.len,
}};
var nread: usize = undefined;
switch (wasi.fd_pread(fd, &iovs, iovs.len, offset, &nread)) {
wasi.ESUCCESS => return nread,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForReading, // Can be a race condition.
wasi.EIO => return error.InputOutput,
wasi.EISDIR => return error.IsDir,
wasi.ENOBUFS => return error.SystemResources,
wasi.ENOMEM => return error.SystemResources,
wasi.ECONNRESET => return error.ConnectionResetByPeer,
wasi.ENXIO => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
while (true) {
const rc = system.pread(fd, buf.ptr, buf.len, offset);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForReading, // Can be a race condition.
EIO => return error.InputOutput,
EISDIR => return error.IsDir,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
ECONNRESET => return error.ConnectionResetByPeer,
ENXIO => return error.Unseekable,
ESPIPE => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
}
pub const TruncateError = error{
FileTooBig,
InputOutput,
FileBusy,
/// In WASI, this error occurs when the file descriptor does
/// not hold the required rights to call `ftruncate` on it.
AccessDenied,
} || UnexpectedError;
pub fn ftruncate(fd: fd_t, length: u64) TruncateError!void {
if (std.Target.current.os.tag == .windows) {
var io_status_block: windows.IO_STATUS_BLOCK = undefined;
var eof_info = windows.FILE_END_OF_FILE_INFORMATION{
.EndOfFile = @bitCast(windows.LARGE_INTEGER, length),
};
const rc = windows.ntdll.NtSetInformationFile(
fd,
&io_status_block,
&eof_info,
@sizeOf(windows.FILE_END_OF_FILE_INFORMATION),
.FileEndOfFileInformation,
);
switch (rc) {
.SUCCESS => return,
.INVALID_HANDLE => unreachable, // Handle not open for writing
.ACCESS_DENIED => return error.AccessDenied,
else => return windows.unexpectedStatus(rc),
}
}
if (std.Target.current.os.tag == .wasi) {
switch (wasi.fd_filestat_set_size(fd, length)) {
wasi.ESUCCESS => return,
wasi.EINTR => unreachable,
wasi.EFBIG => return error.FileTooBig,
wasi.EIO => return error.InputOutput,
wasi.EPERM => return error.AccessDenied,
wasi.ETXTBSY => return error.FileBusy,
wasi.EBADF => unreachable, // Handle not open for writing
wasi.EINVAL => unreachable, // Handle not open for writing
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
while (true) {
const rc = if (builtin.link_libc)
if (std.Target.current.os.tag == .linux)
system.ftruncate64(fd, @bitCast(off_t, length))
else
system.ftruncate(fd, @bitCast(off_t, length))
else
system.ftruncate(fd, length);
switch (errno(rc)) {
0 => return,
EINTR => continue,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
EPERM => return error.AccessDenied,
ETXTBSY => return error.FileBusy,
EBADF => unreachable, // Handle not open for writing
EINVAL => unreachable, // Handle not open for writing
else => |err| return unexpectedErrno(err),
}
}
}
/// Number of bytes read is returned. Upon reading end-of-file, zero is returned.
///
/// Retries when interrupted by a signal.
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
///
/// This operation is non-atomic on the following systems:
/// * Darwin
/// * Windows
/// On these systems, the read races with concurrent writes to the same file descriptor.
pub fn preadv(fd: fd_t, iov: []const iovec, offset: u64) PReadError!usize {
const have_pread_but_not_preadv = switch (std.Target.current.os.tag) {
.windows, .macos, .ios, .watchos, .tvos => true,
else => false,
};
if (have_pread_but_not_preadv) {
// We could loop here; but proper usage of `preadv` must handle partial reads anyway.
// So we simply read into the first vector only.
if (iov.len == 0) return @as(usize, 0);
const first = iov[0];
return pread(fd, first.iov_base[0..first.iov_len], offset);
}
if (builtin.os.tag == .wasi) {
var nread: usize = undefined;
switch (wasi.fd_pread(fd, iov.ptr, iov.len, offset, &nread)) {
wasi.ESUCCESS => return nread,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForReading, // can be a race condition
wasi.EIO => return error.InputOutput,
wasi.EISDIR => return error.IsDir,
wasi.ENOBUFS => return error.SystemResources,
wasi.ENOMEM => return error.SystemResources,
wasi.ENXIO => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const iov_count = math.cast(u31, iov.len) catch math.maxInt(u31);
while (true) {
const rc = system.preadv(fd, iov.ptr, iov_count, offset);
switch (errno(rc)) {
0 => return @bitCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForReading, // can be a race condition
EIO => return error.InputOutput,
EISDIR => return error.IsDir,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
ENXIO => return error.Unseekable,
ESPIPE => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
}
pub const WriteError = error{
DiskQuota,
FileTooBig,
InputOutput,
NoSpaceLeft,
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to write to it.
AccessDenied,
BrokenPipe,
SystemResources,
OperationAborted,
NotOpenForWriting,
/// This error occurs when no global event loop is configured,
/// and reading from the file descriptor would block.
WouldBlock,
} || UnexpectedError;
/// Write to a file descriptor.
/// Retries when interrupted by a signal.
/// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero.
///
/// Note that a successful write() may transfer fewer than count bytes. Such partial writes can
/// occur for various reasons; for example, because there was insufficient space on the disk
/// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or
/// similar was interrupted by a signal handler after it had transferred some, but before it had
/// transferred all of the requested bytes. In the event of a partial write, the caller can make
/// another write() call to transfer the remaining bytes. The subsequent call will either
/// transfer further bytes or may result in an error (e.g., if the disk is now full).
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
///
/// Linux has a limit on how many bytes may be transferred in one `write` call, which is `0x7ffff000`
/// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as
/// well as stuffing the errno codes into the last `4096` values. This is noted on the `write` man page.
/// The limit on Darwin is `0x7fffffff`, trying to read more than that returns EINVAL.
/// The corresponding POSIX limit is `math.maxInt(isize)`.
pub fn write(fd: fd_t, bytes: []const u8) WriteError!usize {
if (builtin.os.tag == .windows) {
return windows.WriteFile(fd, bytes, null, std.io.default_mode);
}
if (builtin.os.tag == .wasi and !builtin.link_libc) {
const ciovs = [_]iovec_const{iovec_const{
.iov_base = bytes.ptr,
.iov_len = bytes.len,
}};
var nwritten: usize = undefined;
switch (wasi.fd_write(fd, &ciovs, ciovs.len, &nwritten)) {
wasi.ESUCCESS => return nwritten,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForWriting, // can be a race condition.
wasi.EDESTADDRREQ => unreachable, // `connect` was never called.
wasi.EDQUOT => return error.DiskQuota,
wasi.EFBIG => return error.FileTooBig,
wasi.EIO => return error.InputOutput,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EPERM => return error.AccessDenied,
wasi.EPIPE => return error.BrokenPipe,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const max_count = switch (std.Target.current.os.tag) {
.linux => 0x7ffff000,
.macos, .ios, .watchos, .tvos => math.maxInt(i32),
else => math.maxInt(isize),
};
const adjusted_len = math.min(max_count, bytes.len);
while (true) {
const rc = system.write(fd, bytes.ptr, adjusted_len);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForWriting, // can be a race condition.
EDESTADDRREQ => unreachable, // `connect` was never called.
EDQUOT => return error.DiskQuota,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EPERM => return error.AccessDenied,
EPIPE => return error.BrokenPipe,
else => |err| return unexpectedErrno(err),
}
}
}
/// Write multiple buffers to a file descriptor.
/// Retries when interrupted by a signal.
/// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero.
///
/// Note that a successful write() may transfer fewer bytes than supplied. Such partial writes can
/// occur for various reasons; for example, because there was insufficient space on the disk
/// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or
/// similar was interrupted by a signal handler after it had transferred some, but before it had
/// transferred all of the requested bytes. In the event of a partial write, the caller can make
/// another write() call to transfer the remaining bytes. The subsequent call will either
/// transfer further bytes or may result in an error (e.g., if the disk is now full).
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.k`.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
///
/// If `iov.len` is larger than will fit in a `u31`, a partial write will occur.
pub fn writev(fd: fd_t, iov: []const iovec_const) WriteError!usize {
if (std.Target.current.os.tag == .windows) {
// TODO improve this to use WriteFileScatter
if (iov.len == 0) return @as(usize, 0);
const first = iov[0];
return write(fd, first.iov_base[0..first.iov_len]);
}
if (builtin.os.tag == .wasi) {
var nwritten: usize = undefined;
switch (wasi.fd_write(fd, iov.ptr, iov.len, &nwritten)) {
wasi.ESUCCESS => return nwritten,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForWriting, // can be a race condition.
wasi.EDESTADDRREQ => unreachable, // `connect` was never called.
wasi.EDQUOT => return error.DiskQuota,
wasi.EFBIG => return error.FileTooBig,
wasi.EIO => return error.InputOutput,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EPERM => return error.AccessDenied,
wasi.EPIPE => return error.BrokenPipe,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const iov_count = math.cast(u31, iov.len) catch math.maxInt(u31);
while (true) {
const rc = system.writev(fd, iov.ptr, iov_count);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForWriting, // Can be a race condition.
EDESTADDRREQ => unreachable, // `connect` was never called.
EDQUOT => return error.DiskQuota,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EPERM => return error.AccessDenied,
EPIPE => return error.BrokenPipe,
else => |err| return unexpectedErrno(err),
}
}
}
pub const PWriteError = WriteError || error{Unseekable};
/// Write to a file descriptor, with a position offset.
/// Retries when interrupted by a signal.
/// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero.
///
/// Note that a successful write() may transfer fewer bytes than supplied. Such partial writes can
/// occur for various reasons; for example, because there was insufficient space on the disk
/// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or
/// similar was interrupted by a signal handler after it had transferred some, but before it had
/// transferred all of the requested bytes. In the event of a partial write, the caller can make
/// another write() call to transfer the remaining bytes. The subsequent call will either
/// transfer further bytes or may result in an error (e.g., if the disk is now full).
///
/// For POSIX systems, if `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
/// On Windows, if the application has a global event loop enabled, I/O Completion Ports are
/// used to perform the I/O. `error.WouldBlock` is not possible on Windows.
///
/// Linux has a limit on how many bytes may be transferred in one `pwrite` call, which is `0x7ffff000`
/// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as
/// well as stuffing the errno codes into the last `4096` values. This is noted on the `write` man page.
/// The limit on Darwin is `0x7fffffff`, trying to write more than that returns EINVAL.
/// The corresponding POSIX limit is `math.maxInt(isize)`.
pub fn pwrite(fd: fd_t, bytes: []const u8, offset: u64) PWriteError!usize {
if (std.Target.current.os.tag == .windows) {
return windows.WriteFile(fd, bytes, offset, std.io.default_mode);
}
if (builtin.os.tag == .wasi) {
const ciovs = [1]iovec_const{iovec_const{
.iov_base = bytes.ptr,
.iov_len = bytes.len,
}};
var nwritten: usize = undefined;
switch (wasi.fd_pwrite(fd, &ciovs, ciovs.len, offset, &nwritten)) {
wasi.ESUCCESS => return nwritten,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForWriting, // can be a race condition.
wasi.EDESTADDRREQ => unreachable, // `connect` was never called.
wasi.EDQUOT => return error.DiskQuota,
wasi.EFBIG => return error.FileTooBig,
wasi.EIO => return error.InputOutput,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EPERM => return error.AccessDenied,
wasi.EPIPE => return error.BrokenPipe,
wasi.ENXIO => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
// Prevent EINVAL.
const max_count = switch (std.Target.current.os.tag) {
.linux => 0x7ffff000,
.macos, .ios, .watchos, .tvos => math.maxInt(i32),
else => math.maxInt(isize),
};
const adjusted_len = math.min(max_count, bytes.len);
while (true) {
const rc = system.pwrite(fd, bytes.ptr, adjusted_len, offset);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForWriting, // Can be a race condition.
EDESTADDRREQ => unreachable, // `connect` was never called.
EDQUOT => return error.DiskQuota,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EPERM => return error.AccessDenied,
EPIPE => return error.BrokenPipe,
ENXIO => return error.Unseekable,
ESPIPE => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
}
/// Write multiple buffers to a file descriptor, with a position offset.
/// Retries when interrupted by a signal.
/// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero.
///
/// Note that a successful write() may transfer fewer than count bytes. Such partial writes can
/// occur for various reasons; for example, because there was insufficient space on the disk
/// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or
/// similar was interrupted by a signal handler after it had transferred some, but before it had
/// transferred all of the requested bytes. In the event of a partial write, the caller can make
/// another write() call to transfer the remaining bytes. The subsequent call will either
/// transfer further bytes or may result in an error (e.g., if the disk is now full).
///
/// If `fd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
///
/// The following systems do not have this syscall, and will return partial writes if more than one
/// vector is provided:
/// * Darwin
/// * Windows
///
/// If `iov.len` is larger than will fit in a `u31`, a partial write will occur.
pub fn pwritev(fd: fd_t, iov: []const iovec_const, offset: u64) PWriteError!usize {
const have_pwrite_but_not_pwritev = switch (std.Target.current.os.tag) {
.windows, .macos, .ios, .watchos, .tvos => true,
else => false,
};
if (have_pwrite_but_not_pwritev) {
// We could loop here; but proper usage of `pwritev` must handle partial writes anyway.
// So we simply write the first vector only.
if (iov.len == 0) return @as(usize, 0);
const first = iov[0];
return pwrite(fd, first.iov_base[0..first.iov_len], offset);
}
if (builtin.os.tag == .wasi) {
var nwritten: usize = undefined;
switch (wasi.fd_pwrite(fd, iov.ptr, iov.len, offset, &nwritten)) {
wasi.ESUCCESS => return nwritten,
wasi.EINTR => unreachable,
wasi.EINVAL => unreachable,
wasi.EFAULT => unreachable,
wasi.EAGAIN => unreachable,
wasi.EBADF => return error.NotOpenForWriting, // Can be a race condition.
wasi.EDESTADDRREQ => unreachable, // `connect` was never called.
wasi.EDQUOT => return error.DiskQuota,
wasi.EFBIG => return error.FileTooBig,
wasi.EIO => return error.InputOutput,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EPERM => return error.AccessDenied,
wasi.EPIPE => return error.BrokenPipe,
wasi.ENXIO => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const iov_count = math.cast(u31, iov.len) catch math.maxInt(u31);
while (true) {
const rc = system.pwritev(fd, iov.ptr, iov_count, offset);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EINVAL => unreachable,
EFAULT => unreachable,
EAGAIN => return error.WouldBlock,
EBADF => return error.NotOpenForWriting, // Can be a race condition.
EDESTADDRREQ => unreachable, // `connect` was never called.
EDQUOT => return error.DiskQuota,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EPERM => return error.AccessDenied,
EPIPE => return error.BrokenPipe,
ENXIO => return error.Unseekable,
ESPIPE => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
}
pub const OpenError = error{
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to open a new resource relative to it.
AccessDenied,
SymLinkLoop,
ProcessFdQuotaExceeded,
SystemFdQuotaExceeded,
NoDevice,
FileNotFound,
/// The path exceeded `MAX_PATH_BYTES` bytes.
NameTooLong,
/// Insufficient kernel memory was available, or
/// the named file is a FIFO and per-user hard limit on
/// memory allocation for pipes has been reached.
SystemResources,
/// The file is too large to be opened. This error is unreachable
/// for 64-bit targets, as well as when opening directories.
FileTooBig,
/// The path refers to directory but the `O_DIRECTORY` flag was not provided.
IsDir,
/// A new path cannot be created because the device has no room for the new file.
/// This error is only reachable when the `O_CREAT` flag is provided.
NoSpaceLeft,
/// A component used as a directory in the path was not, in fact, a directory, or
/// `O_DIRECTORY` was specified and the path was not a directory.
NotDir,
/// The path already exists and the `O_CREAT` and `O_EXCL` flags were provided.
PathAlreadyExists,
DeviceBusy,
/// The underlying filesystem does not support file locks
FileLocksNotSupported,
BadPathName,
InvalidUtf8,
} || UnexpectedError;
/// Open and possibly create a file. Keeps trying if it gets interrupted.
/// See also `openC`.
pub fn open(file_path: []const u8, flags: u32, perm: mode_t) OpenError!fd_t {
if (std.Target.current.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return openW(file_path_w.span(), flags, perm);
}
const file_path_c = try toPosixPath(file_path);
return openZ(&file_path_c, flags, perm);
}
pub const openC = @compileError("deprecated: renamed to openZ");
/// Open and possibly create a file. Keeps trying if it gets interrupted.
/// See also `open`.
pub fn openZ(file_path: [*:0]const u8, flags: u32, perm: mode_t) OpenError!fd_t {
if (std.Target.current.os.tag == .windows) {
const file_path_w = try windows.cStrToPrefixedFileW(file_path);
return openW(file_path_w.span(), flags, perm);
}
while (true) {
const rc = system.open(file_path, flags, perm);
switch (errno(rc)) {
0 => return @intCast(fd_t, rc),
EINTR => continue,
EFAULT => unreachable,
EINVAL => unreachable,
EACCES => return error.AccessDenied,
EFBIG => return error.FileTooBig,
EOVERFLOW => return error.FileTooBig,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
EMFILE => return error.ProcessFdQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENFILE => return error.SystemFdQuotaExceeded,
ENODEV => return error.NoDevice,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
ENOTDIR => return error.NotDir,
EPERM => return error.AccessDenied,
EEXIST => return error.PathAlreadyExists,
EBUSY => return error.DeviceBusy,
else => |err| return unexpectedErrno(err),
}
}
}
fn openOptionsFromFlags(flags: u32) windows.OpenFileOptions {
const w = windows;
var access_mask: w.ULONG = w.READ_CONTROL | w.FILE_WRITE_ATTRIBUTES | w.SYNCHRONIZE;
if (flags & O_RDWR != 0) {
access_mask |= w.GENERIC_READ | w.GENERIC_WRITE;
} else if (flags & O_WRONLY != 0) {
access_mask |= w.GENERIC_WRITE;
} else {
access_mask |= w.GENERIC_READ | w.GENERIC_WRITE;
}
const open_dir: bool = flags & O_DIRECTORY != 0;
const follow_symlinks: bool = flags & O_NOFOLLOW == 0;
const creation: w.ULONG = blk: {
if (flags & O_CREAT != 0) {
if (flags & O_EXCL != 0) {
break :blk w.FILE_CREATE;
}
}
break :blk w.FILE_OPEN;
};
return .{
.access_mask = access_mask,
.io_mode = .blocking,
.creation = creation,
.open_dir = open_dir,
.follow_symlinks = follow_symlinks,
};
}
/// Windows-only. The path parameter is
/// [WTF-16](https://simonsapin.github.io/wtf-8/#potentially-ill-formed-utf-16) encoded.
/// Translates the POSIX open API call to a Windows API call.
/// TODO currently, this function does not handle all flag combinations
/// or makes use of perm argument.
pub fn openW(file_path_w: []const u16, flags: u32, perm: mode_t) OpenError!fd_t {
var options = openOptionsFromFlags(flags);
options.dir = std.fs.cwd().fd;
return windows.OpenFile(file_path_w, options) catch |err| switch (err) {
error.WouldBlock => unreachable,
error.PipeBusy => unreachable,
else => |e| return e,
};
}
/// Open and possibly create a file. Keeps trying if it gets interrupted.
/// `file_path` is relative to the open directory handle `dir_fd`.
/// See also `openatC`.
pub fn openat(dir_fd: fd_t, file_path: []const u8, flags: u32, mode: mode_t) OpenError!fd_t {
if (builtin.os.tag == .wasi) {
@compileError("use openatWasi instead");
}
if (builtin.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return openatW(dir_fd, file_path_w.span(), flags, mode);
}
const file_path_c = try toPosixPath(file_path);
return openatZ(dir_fd, &file_path_c, flags, mode);
}
/// Open and possibly create a file in WASI.
pub fn openatWasi(dir_fd: fd_t, file_path: []const u8, lookup_flags: lookupflags_t, oflags: oflags_t, fdflags: fdflags_t, base: rights_t, inheriting: rights_t) OpenError!fd_t {
while (true) {
var fd: fd_t = undefined;
switch (wasi.path_open(dir_fd, lookup_flags, file_path.ptr, file_path.len, oflags, base, inheriting, fdflags, &fd)) {
wasi.ESUCCESS => return fd,
wasi.EINTR => continue,
wasi.EFAULT => unreachable,
wasi.EINVAL => unreachable,
wasi.EACCES => return error.AccessDenied,
wasi.EFBIG => return error.FileTooBig,
wasi.EOVERFLOW => return error.FileTooBig,
wasi.EISDIR => return error.IsDir,
wasi.ELOOP => return error.SymLinkLoop,
wasi.EMFILE => return error.ProcessFdQuotaExceeded,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENFILE => return error.SystemFdQuotaExceeded,
wasi.ENODEV => return error.NoDevice,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.ENOTDIR => return error.NotDir,
wasi.EPERM => return error.AccessDenied,
wasi.EEXIST => return error.PathAlreadyExists,
wasi.EBUSY => return error.DeviceBusy,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
}
pub const openatC = @compileError("deprecated: renamed to openatZ");
/// Open and possibly create a file. Keeps trying if it gets interrupted.
/// `file_path` is relative to the open directory handle `dir_fd`.
/// See also `openat`.
pub fn openatZ(dir_fd: fd_t, file_path: [*:0]const u8, flags: u32, mode: mode_t) OpenError!fd_t {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.cStrToPrefixedFileW(file_path);
return openatW(dir_fd, file_path_w.span(), flags, mode);
}
while (true) {
const rc = system.openat(dir_fd, file_path, flags, mode);
switch (errno(rc)) {
0 => return @intCast(fd_t, rc),
EINTR => continue,
EFAULT => unreachable,
EINVAL => unreachable,
EACCES => return error.AccessDenied,
EFBIG => return error.FileTooBig,
EOVERFLOW => return error.FileTooBig,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
EMFILE => return error.ProcessFdQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENFILE => return error.SystemFdQuotaExceeded,
ENODEV => return error.NoDevice,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
ENOTDIR => return error.NotDir,
EPERM => return error.AccessDenied,
EEXIST => return error.PathAlreadyExists,
EBUSY => return error.DeviceBusy,
EOPNOTSUPP => return error.FileLocksNotSupported,
else => |err| return unexpectedErrno(err),
}
}
}
/// Windows-only. Similar to `openat` but with pathname argument null-terminated
/// WTF16 encoded.
/// TODO currently, this function does not handle all flag combinations
/// or makes use of perm argument.
pub fn openatW(dir_fd: fd_t, file_path_w: []const u16, flags: u32, mode: mode_t) OpenError!fd_t {
var options = openOptionsFromFlags(flags);
options.dir = dir_fd;
return windows.OpenFile(file_path_w, options) catch |err| switch (err) {
error.WouldBlock => unreachable,
error.PipeBusy => unreachable,
else => |e| return e,
};
}
pub fn dup2(old_fd: fd_t, new_fd: fd_t) !void {
while (true) {
switch (errno(system.dup2(old_fd, new_fd))) {
0 => return,
EBUSY, EINTR => continue,
EMFILE => return error.ProcessFdQuotaExceeded,
EINVAL => unreachable, // invalid parameters passed to dup2
EBADF => unreachable, // invalid file descriptor
else => |err| return unexpectedErrno(err),
}
}
}
pub const ExecveError = error{
SystemResources,
AccessDenied,
InvalidExe,
FileSystem,
IsDir,
FileNotFound,
NotDir,
FileBusy,
ProcessFdQuotaExceeded,
SystemFdQuotaExceeded,
NameTooLong,
} || UnexpectedError;
pub const execveC = @compileError("deprecated: use execveZ");
/// Like `execve` except the parameters are null-terminated,
/// matching the syscall API on all targets. This removes the need for an allocator.
/// This function ignores PATH environment variable. See `execvpeZ` for that.
pub fn execveZ(
path: [*:0]const u8,
child_argv: [*:null]const ?[*:0]const u8,
envp: [*:null]const ?[*:0]const u8,
) ExecveError {
switch (errno(system.execve(path, child_argv, envp))) {
0 => unreachable,
EFAULT => unreachable,
E2BIG => return error.SystemResources,
EMFILE => return error.ProcessFdQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENFILE => return error.SystemFdQuotaExceeded,
ENOMEM => return error.SystemResources,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EINVAL => return error.InvalidExe,
ENOEXEC => return error.InvalidExe,
EIO => return error.FileSystem,
ELOOP => return error.FileSystem,
EISDIR => return error.IsDir,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ETXTBSY => return error.FileBusy,
else => |err| return unexpectedErrno(err),
}
}
pub const execvpeC = @compileError("deprecated in favor of execvpeZ");
pub const Arg0Expand = enum {
expand,
no_expand,
};
/// Like `execvpeZ` except if `arg0_expand` is `.expand`, then `argv` is mutable,
/// and `argv[0]` is expanded to be the same absolute path that is passed to the execve syscall.
/// If this function returns with an error, `argv[0]` will be restored to the value it was when it was passed in.
pub fn execvpeZ_expandArg0(
comptime arg0_expand: Arg0Expand,
file: [*:0]const u8,
child_argv: switch (arg0_expand) {
.expand => [*:null]?[*:0]const u8,
.no_expand => [*:null]const ?[*:0]const u8,
},
envp: [*:null]const ?[*:0]const u8,
) ExecveError {
const file_slice = mem.spanZ(file);
if (mem.indexOfScalar(u8, file_slice, '/') != null) return execveZ(file, child_argv, envp);
const PATH = getenvZ("PATH") orelse "/usr/local/bin:/bin/:/usr/bin";
// Use of MAX_PATH_BYTES here is valid as the path_buf will be passed
// directly to the operating system in execveZ.
var path_buf: [MAX_PATH_BYTES]u8 = undefined;
var it = mem.tokenize(PATH, ":");
var seen_eacces = false;
var err: ExecveError = undefined;
// In case of expanding arg0 we must put it back if we return with an error.
const prev_arg0 = child_argv[0];
defer switch (arg0_expand) {
.expand => child_argv[0] = prev_arg0,
.no_expand => {},
};
while (it.next()) |search_path| {
if (path_buf.len < search_path.len + file_slice.len + 1) return error.NameTooLong;
mem.copy(u8, &path_buf, search_path);
path_buf[search_path.len] = '/';
mem.copy(u8, path_buf[search_path.len + 1 ..], file_slice);
const path_len = search_path.len + file_slice.len + 1;
path_buf[path_len] = 0;
const full_path = path_buf[0..path_len :0].ptr;
switch (arg0_expand) {
.expand => child_argv[0] = full_path,
.no_expand => {},
}
err = execveZ(full_path, child_argv, envp);
switch (err) {
error.AccessDenied => seen_eacces = true,
error.FileNotFound, error.NotDir => {},
else => |e| return e,
}
}
if (seen_eacces) return error.AccessDenied;
return err;
}
/// Like `execvpe` except the parameters are null-terminated,
/// matching the syscall API on all targets. This removes the need for an allocator.
/// This function also uses the PATH environment variable to get the full path to the executable.
/// If `file` is an absolute path, this is the same as `execveZ`.
pub fn execvpeZ(
file: [*:0]const u8,
argv: [*:null]const ?[*:0]const u8,
envp: [*:null]const ?[*:0]const u8,
) ExecveError {
return execvpeZ_expandArg0(.no_expand, file, argv, envp);
}
/// This is the same as `execvpe` except if the `arg0_expand` parameter is set to `.expand`,
/// then argv[0] will be replaced with the expanded version of it, after resolving in accordance
/// with the PATH environment variable.
pub fn execvpe_expandArg0(
allocator: *mem.Allocator,
arg0_expand: Arg0Expand,
argv_slice: []const []const u8,
env_map: *const std.BufMap,
) (ExecveError || error{OutOfMemory}) {
const argv_buf = try allocator.alloc(?[*:0]u8, argv_slice.len + 1);
mem.set(?[*:0]u8, argv_buf, null);
defer {
for (argv_buf) |arg| {
const arg_buf = mem.spanZ(arg) orelse break;
allocator.free(arg_buf);
}
allocator.free(argv_buf);
}
for (argv_slice) |arg, i| {
const arg_buf = try allocator.alloc(u8, arg.len + 1);
@memcpy(arg_buf.ptr, arg.ptr, arg.len);
arg_buf[arg.len] = 0;
argv_buf[i] = arg_buf[0..arg.len :0].ptr;
}
argv_buf[argv_slice.len] = null;
const argv_ptr = argv_buf[0..argv_slice.len :null].ptr;
const envp_buf = try createNullDelimitedEnvMap(allocator, env_map);
defer freeNullDelimitedEnvMap(allocator, envp_buf);
switch (arg0_expand) {
.expand => return execvpeZ_expandArg0(.expand, argv_buf.ptr[0].?, argv_ptr, envp_buf.ptr),
.no_expand => return execvpeZ_expandArg0(.no_expand, argv_buf.ptr[0].?, argv_ptr, envp_buf.ptr),
}
}
/// This function must allocate memory to add a null terminating bytes on path and each arg.
/// It must also convert to KEY=VALUE\0 format for environment variables, and include null
/// pointers after the args and after the environment variables.
/// `argv_slice[0]` is the executable path.
/// This function also uses the PATH environment variable to get the full path to the executable.
pub fn execvpe(
allocator: *mem.Allocator,
argv_slice: []const []const u8,
env_map: *const std.BufMap,
) (ExecveError || error{OutOfMemory}) {
return execvpe_expandArg0(allocator, .no_expand, argv_slice, env_map);
}
pub fn createNullDelimitedEnvMap(allocator: *mem.Allocator, env_map: *const std.BufMap) ![:null]?[*:0]u8 {
const envp_count = env_map.count();
const envp_buf = try allocator.alloc(?[*:0]u8, envp_count + 1);
mem.set(?[*:0]u8, envp_buf, null);
errdefer freeNullDelimitedEnvMap(allocator, envp_buf);
{
var it = env_map.iterator();
var i: usize = 0;
while (it.next()) |pair| : (i += 1) {
const env_buf = try allocator.alloc(u8, pair.key.len + pair.value.len + 2);
@memcpy(env_buf.ptr, pair.key.ptr, pair.key.len);
env_buf[pair.key.len] = '=';
@memcpy(env_buf.ptr + pair.key.len + 1, pair.value.ptr, pair.value.len);
const len = env_buf.len - 1;
env_buf[len] = 0;
envp_buf[i] = env_buf[0..len :0].ptr;
}
assert(i == envp_count);
}
return envp_buf[0..envp_count :null];
}
pub fn freeNullDelimitedEnvMap(allocator: *mem.Allocator, envp_buf: []?[*:0]u8) void {
for (envp_buf) |env| {
const env_buf = if (env) |ptr| ptr[0 .. mem.len(ptr) + 1] else break;
allocator.free(env_buf);
}
allocator.free(envp_buf);
}
/// Get an environment variable.
/// See also `getenvZ`.
pub fn getenv(key: []const u8) ?[]const u8 {
if (builtin.link_libc) {
var small_key_buf: [64]u8 = undefined;
if (key.len < small_key_buf.len) {
mem.copy(u8, &small_key_buf, key);
small_key_buf[key.len] = 0;
const key0 = small_key_buf[0..key.len :0];
return getenvZ(key0);
}
// Search the entire `environ` because we don't have a null terminated pointer.
var ptr = std.c.environ;
while (ptr.*) |line| : (ptr += 1) {
var line_i: usize = 0;
while (line[line_i] != 0 and line[line_i] != '=') : (line_i += 1) {}
const this_key = line[0..line_i];
if (!mem.eql(u8, this_key, key)) continue;
var end_i: usize = line_i;
while (line[end_i] != 0) : (end_i += 1) {}
const value = line[line_i + 1 .. end_i];
return value;
}
return null;
}
if (builtin.os.tag == .windows) {
@compileError("std.os.getenv is unavailable for Windows because environment string is in WTF-16 format. See std.process.getEnvVarOwned for cross-platform API or std.os.getenvW for Windows-specific API.");
}
// TODO see https://github.com/ziglang/zig/issues/4524
for (environ) |ptr| {
var line_i: usize = 0;
while (ptr[line_i] != 0 and ptr[line_i] != '=') : (line_i += 1) {}
const this_key = ptr[0..line_i];
if (!mem.eql(u8, key, this_key)) continue;
var end_i: usize = line_i;
while (ptr[end_i] != 0) : (end_i += 1) {}
const this_value = ptr[line_i + 1 .. end_i];
return this_value;
}
return null;
}
pub const getenvC = @compileError("Deprecated in favor of `getenvZ`");
/// Get an environment variable with a null-terminated name.
/// See also `getenv`.
pub fn getenvZ(key: [*:0]const u8) ?[]const u8 {
if (builtin.link_libc) {
const value = system.getenv(key) orelse return null;
return mem.spanZ(value);
}
if (builtin.os.tag == .windows) {
@compileError("std.os.getenvZ is unavailable for Windows because environment string is in WTF-16 format. See std.process.getEnvVarOwned for cross-platform API or std.os.getenvW for Windows-specific API.");
}
return getenv(mem.spanZ(key));
}
/// Windows-only. Get an environment variable with a null-terminated, WTF-16 encoded name.
/// See also `getenv`.
/// This function first attempts a case-sensitive lookup. If no match is found, and `key`
/// is ASCII, then it attempts a second case-insensitive lookup.
pub fn getenvW(key: [*:0]const u16) ?[:0]const u16 {
if (builtin.os.tag != .windows) {
@compileError("std.os.getenvW is a Windows-only API");
}
const key_slice = mem.spanZ(key);
const ptr = windows.peb().ProcessParameters.Environment;
var ascii_match: ?[:0]const u16 = null;
var i: usize = 0;
while (ptr[i] != 0) {
const key_start = i;
while (ptr[i] != 0 and ptr[i] != '=') : (i += 1) {}
const this_key = ptr[key_start..i];
if (ptr[i] == '=') i += 1;
const value_start = i;
while (ptr[i] != 0) : (i += 1) {}
const this_value = ptr[value_start..i :0];
if (mem.eql(u16, key_slice, this_key)) return this_value;
ascii_check: {
if (ascii_match != null) break :ascii_check;
if (key_slice.len != this_key.len) break :ascii_check;
for (key_slice) |a_c, key_index| {
const a = math.cast(u8, a_c) catch break :ascii_check;
const b = math.cast(u8, this_key[key_index]) catch break :ascii_check;
if (std.ascii.toLower(a) != std.ascii.toLower(b)) break :ascii_check;
}
ascii_match = this_value;
}
i += 1; // skip over null byte
}
return ascii_match;
}
pub const GetCwdError = error{
NameTooLong,
CurrentWorkingDirectoryUnlinked,
} || UnexpectedError;
/// The result is a slice of out_buffer, indexed from 0.
pub fn getcwd(out_buffer: []u8) GetCwdError![]u8 {
if (builtin.os.tag == .windows) {
return windows.GetCurrentDirectory(out_buffer);
}
if (builtin.os.tag == .wasi) {
@compileError("WASI doesn't have a concept of cwd(); use std.fs.wasi.PreopenList to get available Dir handles instead");
}
const err = if (builtin.link_libc) blk: {
break :blk if (std.c.getcwd(out_buffer.ptr, out_buffer.len)) |_| 0 else std.c._errno().*;
} else blk: {
break :blk errno(system.getcwd(out_buffer.ptr, out_buffer.len));
};
switch (err) {
0 => return mem.spanZ(@ptrCast([*:0]u8, out_buffer.ptr)),
EFAULT => unreachable,
EINVAL => unreachable,
ENOENT => return error.CurrentWorkingDirectoryUnlinked,
ERANGE => return error.NameTooLong,
else => return unexpectedErrno(@intCast(usize, err)),
}
}
pub const SymLinkError = error{
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to create a new symbolic link relative to it.
AccessDenied,
DiskQuota,
PathAlreadyExists,
FileSystem,
SymLinkLoop,
FileNotFound,
SystemResources,
NoSpaceLeft,
ReadOnlyFileSystem,
NotDir,
NameTooLong,
InvalidUtf8,
BadPathName,
} || UnexpectedError;
/// Creates a symbolic link named `sym_link_path` which contains the string `target_path`.
/// A symbolic link (also known as a soft link) may point to an existing file or to a nonexistent
/// one; the latter case is known as a dangling link.
/// If `sym_link_path` exists, it will not be overwritten.
/// See also `symlinkZ.
pub fn symlink(target_path: []const u8, sym_link_path: []const u8) SymLinkError!void {
if (builtin.os.tag == .wasi) {
@compileError("symlink is not supported in WASI; use symlinkat instead");
}
if (builtin.os.tag == .windows) {
@compileError("symlink is not supported on Windows; use std.os.windows.CreateSymbolicLink instead");
}
const target_path_c = try toPosixPath(target_path);
const sym_link_path_c = try toPosixPath(sym_link_path);
return symlinkZ(&target_path_c, &sym_link_path_c);
}
pub const symlinkC = @compileError("deprecated: renamed to symlinkZ");
/// This is the same as `symlink` except the parameters are null-terminated pointers.
/// See also `symlink`.
pub fn symlinkZ(target_path: [*:0]const u8, sym_link_path: [*:0]const u8) SymLinkError!void {
if (builtin.os.tag == .windows) {
@compileError("symlink is not supported on Windows; use std.os.windows.CreateSymbolicLink instead");
}
switch (errno(system.symlink(target_path, sym_link_path))) {
0 => return,
EFAULT => unreachable,
EINVAL => unreachable,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EDQUOT => return error.DiskQuota,
EEXIST => return error.PathAlreadyExists,
EIO => return error.FileSystem,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
/// Similar to `symlink`, however, creates a symbolic link named `sym_link_path` which contains the string
/// `target_path` **relative** to `newdirfd` directory handle.
/// A symbolic link (also known as a soft link) may point to an existing file or to a nonexistent
/// one; the latter case is known as a dangling link.
/// If `sym_link_path` exists, it will not be overwritten.
/// See also `symlinkatWasi`, `symlinkatZ` and `symlinkatW`.
pub fn symlinkat(target_path: []const u8, newdirfd: fd_t, sym_link_path: []const u8) SymLinkError!void {
if (builtin.os.tag == .wasi) {
return symlinkatWasi(target_path, newdirfd, sym_link_path);
}
if (builtin.os.tag == .windows) {
@compileError("symlinkat is not supported on Windows; use std.os.windows.CreateSymbolicLink instead");
}
const target_path_c = try toPosixPath(target_path);
const sym_link_path_c = try toPosixPath(sym_link_path);
return symlinkatZ(&target_path_c, newdirfd, &sym_link_path_c);
}
pub const symlinkatC = @compileError("deprecated: renamed to symlinkatZ");
/// WASI-only. The same as `symlinkat` but targeting WASI.
/// See also `symlinkat`.
pub fn symlinkatWasi(target_path: []const u8, newdirfd: fd_t, sym_link_path: []const u8) SymLinkError!void {
switch (wasi.path_symlink(target_path.ptr, target_path.len, newdirfd, sym_link_path.ptr, sym_link_path.len)) {
wasi.ESUCCESS => {},
wasi.EFAULT => unreachable,
wasi.EINVAL => unreachable,
wasi.EACCES => return error.AccessDenied,
wasi.EPERM => return error.AccessDenied,
wasi.EDQUOT => return error.DiskQuota,
wasi.EEXIST => return error.PathAlreadyExists,
wasi.EIO => return error.FileSystem,
wasi.ELOOP => return error.SymLinkLoop,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOTDIR => return error.NotDir,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EROFS => return error.ReadOnlyFileSystem,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
/// The same as `symlinkat` except the parameters are null-terminated pointers.
/// See also `symlinkat`.
pub fn symlinkatZ(target_path: [*:0]const u8, newdirfd: fd_t, sym_link_path: [*:0]const u8) SymLinkError!void {
if (builtin.os.tag == .windows) {
@compileError("symlinkat is not supported on Windows; use std.os.windows.CreateSymbolicLink instead");
}
switch (errno(system.symlinkat(target_path, newdirfd, sym_link_path))) {
0 => return,
EFAULT => unreachable,
EINVAL => unreachable,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EDQUOT => return error.DiskQuota,
EEXIST => return error.PathAlreadyExists,
EIO => return error.FileSystem,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
pub const UnlinkError = error{
FileNotFound,
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to unlink a resource by path relative to it.
AccessDenied,
FileBusy,
FileSystem,
IsDir,
SymLinkLoop,
NameTooLong,
NotDir,
SystemResources,
ReadOnlyFileSystem,
/// On Windows, file paths must be valid Unicode.
InvalidUtf8,
/// On Windows, file paths cannot contain these characters:
/// '/', '*', '?', '"', '<', '>', '|'
BadPathName,
} || UnexpectedError;
/// Delete a name and possibly the file it refers to.
/// See also `unlinkC`.
pub fn unlink(file_path: []const u8) UnlinkError!void {
if (builtin.os.tag == .wasi) {
@compileError("unlink is not supported in WASI; use unlinkat instead");
} else if (builtin.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return unlinkW(file_path_w.span());
} else {
const file_path_c = try toPosixPath(file_path);
return unlinkZ(&file_path_c);
}
}
pub const unlinkC = @compileError("deprecated: renamed to unlinkZ");
/// Same as `unlink` except the parameter is a null terminated UTF8-encoded string.
pub fn unlinkZ(file_path: [*:0]const u8) UnlinkError!void {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.cStrToPrefixedFileW(file_path);
return unlinkW(file_path_w.span());
}
switch (errno(system.unlink(file_path))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EBUSY => return error.FileBusy,
EFAULT => unreachable,
EINVAL => unreachable,
EIO => return error.FileSystem,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
/// Windows-only. Same as `unlink` except the parameter is null-terminated, WTF16 encoded.
pub fn unlinkW(file_path_w: []const u16) UnlinkError!void {
return windows.DeleteFile(file_path_w, .{ .dir = std.fs.cwd().fd });
}
pub const UnlinkatError = UnlinkError || error{
/// When passing `AT_REMOVEDIR`, this error occurs when the named directory is not empty.
DirNotEmpty,
};
/// Delete a file name and possibly the file it refers to, based on an open directory handle.
/// Asserts that the path parameter has no null bytes.
pub fn unlinkat(dirfd: fd_t, file_path: []const u8, flags: u32) UnlinkatError!void {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return unlinkatW(dirfd, file_path_w.span(), flags);
} else if (builtin.os.tag == .wasi) {
return unlinkatWasi(dirfd, file_path, flags);
} else {
const file_path_c = try toPosixPath(file_path);
return unlinkatZ(dirfd, &file_path_c, flags);
}
}
pub const unlinkatC = @compileError("deprecated: renamed to unlinkatZ");
/// WASI-only. Same as `unlinkat` but targeting WASI.
/// See also `unlinkat`.
pub fn unlinkatWasi(dirfd: fd_t, file_path: []const u8, flags: u32) UnlinkatError!void {
const remove_dir = (flags & AT_REMOVEDIR) != 0;
const res = if (remove_dir)
wasi.path_remove_directory(dirfd, file_path.ptr, file_path.len)
else
wasi.path_unlink_file(dirfd, file_path.ptr, file_path.len);
switch (res) {
wasi.ESUCCESS => return,
wasi.EACCES => return error.AccessDenied,
wasi.EPERM => return error.AccessDenied,
wasi.EBUSY => return error.FileBusy,
wasi.EFAULT => unreachable,
wasi.EIO => return error.FileSystem,
wasi.EISDIR => return error.IsDir,
wasi.ELOOP => return error.SymLinkLoop,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOTDIR => return error.NotDir,
wasi.ENOMEM => return error.SystemResources,
wasi.EROFS => return error.ReadOnlyFileSystem,
wasi.ENOTEMPTY => return error.DirNotEmpty,
wasi.ENOTCAPABLE => return error.AccessDenied,
wasi.EINVAL => unreachable, // invalid flags, or pathname has . as last component
wasi.EBADF => unreachable, // always a race condition
else => |err| return unexpectedErrno(err),
}
}
/// Same as `unlinkat` but `file_path` is a null-terminated string.
pub fn unlinkatZ(dirfd: fd_t, file_path_c: [*:0]const u8, flags: u32) UnlinkatError!void {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.cStrToPrefixedFileW(file_path_c);
return unlinkatW(dirfd, file_path_w.span(), flags);
}
switch (errno(system.unlinkat(dirfd, file_path_c, flags))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EBUSY => return error.FileBusy,
EFAULT => unreachable,
EIO => return error.FileSystem,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
EROFS => return error.ReadOnlyFileSystem,
ENOTEMPTY => return error.DirNotEmpty,
EINVAL => unreachable, // invalid flags, or pathname has . as last component
EBADF => unreachable, // always a race condition
else => |err| return unexpectedErrno(err),
}
}
/// Same as `unlinkat` but `sub_path_w` is UTF16LE, NT prefixed. Windows only.
pub fn unlinkatW(dirfd: fd_t, sub_path_w: []const u16, flags: u32) UnlinkatError!void {
const remove_dir = (flags & AT_REMOVEDIR) != 0;
return windows.DeleteFile(sub_path_w, .{ .dir = dirfd, .remove_dir = remove_dir });
}
pub const RenameError = error{
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to rename a resource by path relative to it.
AccessDenied,
FileBusy,
DiskQuota,
IsDir,
SymLinkLoop,
LinkQuotaExceeded,
NameTooLong,
FileNotFound,
NotDir,
SystemResources,
NoSpaceLeft,
PathAlreadyExists,
ReadOnlyFileSystem,
RenameAcrossMountPoints,
InvalidUtf8,
BadPathName,
NoDevice,
SharingViolation,
PipeBusy,
} || UnexpectedError;
/// Change the name or location of a file.
pub fn rename(old_path: []const u8, new_path: []const u8) RenameError!void {
if (builtin.os.tag == .wasi) {
@compileError("rename is not supported in WASI; use renameat instead");
} else if (builtin.os.tag == .windows) {
const old_path_w = try windows.sliceToPrefixedFileW(old_path);
const new_path_w = try windows.sliceToPrefixedFileW(new_path);
return renameW(old_path_w.span().ptr, new_path_w.span().ptr);
} else {
const old_path_c = try toPosixPath(old_path);
const new_path_c = try toPosixPath(new_path);
return renameZ(&old_path_c, &new_path_c);
}
}
pub const renameC = @compileError("deprecated: renamed to renameZ");
/// Same as `rename` except the parameters are null-terminated byte arrays.
pub fn renameZ(old_path: [*:0]const u8, new_path: [*:0]const u8) RenameError!void {
if (builtin.os.tag == .windows) {
const old_path_w = try windows.cStrToPrefixedFileW(old_path);
const new_path_w = try windows.cStrToPrefixedFileW(new_path);
return renameW(old_path_w.span().ptr, new_path_w.span().ptr);
}
switch (errno(system.rename(old_path, new_path))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EBUSY => return error.FileBusy,
EDQUOT => return error.DiskQuota,
EFAULT => unreachable,
EINVAL => unreachable,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
EMLINK => return error.LinkQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
EEXIST => return error.PathAlreadyExists,
ENOTEMPTY => return error.PathAlreadyExists,
EROFS => return error.ReadOnlyFileSystem,
EXDEV => return error.RenameAcrossMountPoints,
else => |err| return unexpectedErrno(err),
}
}
/// Same as `rename` except the parameters are null-terminated UTF16LE encoded byte arrays.
/// Assumes target is Windows.
pub fn renameW(old_path: [*:0]const u16, new_path: [*:0]const u16) RenameError!void {
const flags = windows.MOVEFILE_REPLACE_EXISTING | windows.MOVEFILE_WRITE_THROUGH;
return windows.MoveFileExW(old_path, new_path, flags);
}
/// Change the name or location of a file based on an open directory handle.
pub fn renameat(
old_dir_fd: fd_t,
old_path: []const u8,
new_dir_fd: fd_t,
new_path: []const u8,
) RenameError!void {
if (builtin.os.tag == .windows) {
const old_path_w = try windows.sliceToPrefixedFileW(old_path);
const new_path_w = try windows.sliceToPrefixedFileW(new_path);
return renameatW(old_dir_fd, old_path_w.span(), new_dir_fd, new_path_w.span(), windows.TRUE);
} else if (builtin.os.tag == .wasi) {
return renameatWasi(old_dir_fd, old_path, new_dir_fd, new_path);
} else {
const old_path_c = try toPosixPath(old_path);
const new_path_c = try toPosixPath(new_path);
return renameatZ(old_dir_fd, &old_path_c, new_dir_fd, &new_path_c);
}
}
/// WASI-only. Same as `renameat` expect targeting WASI.
/// See also `renameat`.
pub fn renameatWasi(old_dir_fd: fd_t, old_path: []const u8, new_dir_fd: fd_t, new_path: []const u8) RenameError!void {
switch (wasi.path_rename(old_dir_fd, old_path.ptr, old_path.len, new_dir_fd, new_path.ptr, new_path.len)) {
wasi.ESUCCESS => return,
wasi.EACCES => return error.AccessDenied,
wasi.EPERM => return error.AccessDenied,
wasi.EBUSY => return error.FileBusy,
wasi.EDQUOT => return error.DiskQuota,
wasi.EFAULT => unreachable,
wasi.EINVAL => unreachable,
wasi.EISDIR => return error.IsDir,
wasi.ELOOP => return error.SymLinkLoop,
wasi.EMLINK => return error.LinkQuotaExceeded,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOTDIR => return error.NotDir,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.EEXIST => return error.PathAlreadyExists,
wasi.ENOTEMPTY => return error.PathAlreadyExists,
wasi.EROFS => return error.ReadOnlyFileSystem,
wasi.EXDEV => return error.RenameAcrossMountPoints,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Same as `renameat` except the parameters are null-terminated byte arrays.
pub fn renameatZ(
old_dir_fd: fd_t,
old_path: [*:0]const u8,
new_dir_fd: fd_t,
new_path: [*:0]const u8,
) RenameError!void {
if (builtin.os.tag == .windows) {
const old_path_w = try windows.cStrToPrefixedFileW(old_path);
const new_path_w = try windows.cStrToPrefixedFileW(new_path);
return renameatW(old_dir_fd, old_path_w.span(), new_dir_fd, new_path_w.span(), windows.TRUE);
}
switch (errno(system.renameat(old_dir_fd, old_path, new_dir_fd, new_path))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EBUSY => return error.FileBusy,
EDQUOT => return error.DiskQuota,
EFAULT => unreachable,
EINVAL => unreachable,
EISDIR => return error.IsDir,
ELOOP => return error.SymLinkLoop,
EMLINK => return error.LinkQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.NotDir,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
EEXIST => return error.PathAlreadyExists,
ENOTEMPTY => return error.PathAlreadyExists,
EROFS => return error.ReadOnlyFileSystem,
EXDEV => return error.RenameAcrossMountPoints,
else => |err| return unexpectedErrno(err),
}
}
/// Same as `renameat` but Windows-only and the path parameters are
/// [WTF-16](https://simonsapin.github.io/wtf-8/#potentially-ill-formed-utf-16) encoded.
pub fn renameatW(
old_dir_fd: fd_t,
old_path_w: []const u16,
new_dir_fd: fd_t,
new_path_w: []const u16,
ReplaceIfExists: windows.BOOLEAN,
) RenameError!void {
const src_fd = windows.OpenFile(old_path_w, .{
.dir = old_dir_fd,
.access_mask = windows.SYNCHRONIZE | windows.GENERIC_WRITE | windows.DELETE,
.creation = windows.FILE_OPEN,
.io_mode = .blocking,
}) catch |err| switch (err) {
error.WouldBlock => unreachable, // Not possible without `.share_access_nonblocking = true`.
else => |e| return e,
};
defer windows.CloseHandle(src_fd);
const struct_buf_len = @sizeOf(windows.FILE_RENAME_INFORMATION) + (MAX_PATH_BYTES - 1);
var rename_info_buf: [struct_buf_len]u8 align(@alignOf(windows.FILE_RENAME_INFORMATION)) = undefined;
const struct_len = @sizeOf(windows.FILE_RENAME_INFORMATION) - 1 + new_path_w.len * 2;
if (struct_len > struct_buf_len) return error.NameTooLong;
const rename_info = @ptrCast(*windows.FILE_RENAME_INFORMATION, &rename_info_buf);
rename_info.* = .{
.ReplaceIfExists = ReplaceIfExists,
.RootDirectory = if (std.fs.path.isAbsoluteWindowsWTF16(new_path_w)) null else new_dir_fd,
.FileNameLength = @intCast(u32, new_path_w.len * 2), // already checked error.NameTooLong
.FileName = undefined,
};
std.mem.copy(u16, @as([*]u16, &rename_info.FileName)[0..new_path_w.len], new_path_w);
var io_status_block: windows.IO_STATUS_BLOCK = undefined;
const rc = windows.ntdll.NtSetInformationFile(
src_fd,
&io_status_block,
rename_info,
@intCast(u32, struct_len), // already checked for error.NameTooLong
.FileRenameInformation,
);
switch (rc) {
.SUCCESS => return,
.INVALID_HANDLE => unreachable,
.INVALID_PARAMETER => unreachable,
.OBJECT_PATH_SYNTAX_BAD => unreachable,
.ACCESS_DENIED => return error.AccessDenied,
.OBJECT_NAME_NOT_FOUND => return error.FileNotFound,
.OBJECT_PATH_NOT_FOUND => return error.FileNotFound,
.NOT_SAME_DEVICE => return error.RenameAcrossMountPoints,
else => return windows.unexpectedStatus(rc),
}
}
pub fn mkdirat(dir_fd: fd_t, sub_dir_path: []const u8, mode: u32) MakeDirError!void {
if (builtin.os.tag == .windows) {
const sub_dir_path_w = try windows.sliceToPrefixedFileW(sub_dir_path);
return mkdiratW(dir_fd, sub_dir_path_w.span(), mode);
} else if (builtin.os.tag == .wasi) {
return mkdiratWasi(dir_fd, sub_dir_path, mode);
} else {
const sub_dir_path_c = try toPosixPath(sub_dir_path);
return mkdiratZ(dir_fd, &sub_dir_path_c, mode);
}
}
pub const mkdiratC = @compileError("deprecated: renamed to mkdiratZ");
pub fn mkdiratWasi(dir_fd: fd_t, sub_dir_path: []const u8, mode: u32) MakeDirError!void {
switch (wasi.path_create_directory(dir_fd, sub_dir_path.ptr, sub_dir_path.len)) {
wasi.ESUCCESS => return,
wasi.EACCES => return error.AccessDenied,
wasi.EBADF => unreachable,
wasi.EPERM => return error.AccessDenied,
wasi.EDQUOT => return error.DiskQuota,
wasi.EEXIST => return error.PathAlreadyExists,
wasi.EFAULT => unreachable,
wasi.ELOOP => return error.SymLinkLoop,
wasi.EMLINK => return error.LinkQuotaExceeded,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOSPC => return error.NoSpaceLeft,
wasi.ENOTDIR => return error.NotDir,
wasi.EROFS => return error.ReadOnlyFileSystem,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn mkdiratZ(dir_fd: fd_t, sub_dir_path: [*:0]const u8, mode: u32) MakeDirError!void {
if (builtin.os.tag == .windows) {
const sub_dir_path_w = try windows.cStrToPrefixedFileW(sub_dir_path);
return mkdiratW(dir_fd, sub_dir_path_w.span().ptr, mode);
}
switch (errno(system.mkdirat(dir_fd, sub_dir_path, mode))) {
0 => return,
EACCES => return error.AccessDenied,
EBADF => unreachable,
EPERM => return error.AccessDenied,
EDQUOT => return error.DiskQuota,
EEXIST => return error.PathAlreadyExists,
EFAULT => unreachable,
ELOOP => return error.SymLinkLoop,
EMLINK => return error.LinkQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
ENOTDIR => return error.NotDir,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
pub fn mkdiratW(dir_fd: fd_t, sub_path_w: []const u16, mode: u32) MakeDirError!void {
const sub_dir_handle = windows.OpenFile(sub_path_w, .{
.dir = dir_fd,
.access_mask = windows.GENERIC_READ | windows.SYNCHRONIZE,
.creation = windows.FILE_CREATE,
.io_mode = .blocking,
.open_dir = true,
}) catch |err| switch (err) {
error.IsDir => unreachable,
error.PipeBusy => unreachable,
error.WouldBlock => unreachable,
else => |e| return e,
};
windows.CloseHandle(sub_dir_handle);
}
pub const MakeDirError = error{
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to create a new directory relative to it.
AccessDenied,
DiskQuota,
PathAlreadyExists,
SymLinkLoop,
LinkQuotaExceeded,
NameTooLong,
FileNotFound,
SystemResources,
NoSpaceLeft,
NotDir,
ReadOnlyFileSystem,
InvalidUtf8,
BadPathName,
NoDevice,
} || UnexpectedError;
/// Create a directory.
/// `mode` is ignored on Windows.
pub fn mkdir(dir_path: []const u8, mode: u32) MakeDirError!void {
if (builtin.os.tag == .wasi) {
@compileError("mkdir is not supported in WASI; use mkdirat instead");
} else if (builtin.os.tag == .windows) {
const dir_path_w = try windows.sliceToPrefixedFileW(dir_path);
return mkdirW(dir_path_w.span(), mode);
} else {
const dir_path_c = try toPosixPath(dir_path);
return mkdirZ(&dir_path_c, mode);
}
}
/// Same as `mkdir` but the parameter is a null-terminated UTF8-encoded string.
pub fn mkdirZ(dir_path: [*:0]const u8, mode: u32) MakeDirError!void {
if (builtin.os.tag == .windows) {
const dir_path_w = try windows.cStrToPrefixedFileW(dir_path);
return mkdirW(dir_path_w.span(), mode);
}
switch (errno(system.mkdir(dir_path, mode))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EDQUOT => return error.DiskQuota,
EEXIST => return error.PathAlreadyExists,
EFAULT => unreachable,
ELOOP => return error.SymLinkLoop,
EMLINK => return error.LinkQuotaExceeded,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOSPC => return error.NoSpaceLeft,
ENOTDIR => return error.NotDir,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
/// Windows-only. Same as `mkdir` but the parameters is WTF16 encoded.
pub fn mkdirW(dir_path_w: []const u16, mode: u32) MakeDirError!void {
const sub_dir_handle = windows.OpenFile(dir_path_w, .{
.dir = std.fs.cwd().fd,
.access_mask = windows.GENERIC_READ | windows.SYNCHRONIZE,
.creation = windows.FILE_CREATE,
.io_mode = .blocking,
.open_dir = true,
}) catch |err| switch (err) {
error.IsDir => unreachable,
error.PipeBusy => unreachable,
error.WouldBlock => unreachable,
else => |e| return e,
};
windows.CloseHandle(sub_dir_handle);
}
pub const DeleteDirError = error{
AccessDenied,
FileBusy,
SymLinkLoop,
NameTooLong,
FileNotFound,
SystemResources,
NotDir,
DirNotEmpty,
ReadOnlyFileSystem,
InvalidUtf8,
BadPathName,
} || UnexpectedError;
/// Deletes an empty directory.
pub fn rmdir(dir_path: []const u8) DeleteDirError!void {
if (builtin.os.tag == .wasi) {
@compileError("rmdir is not supported in WASI; use unlinkat instead");
} else if (builtin.os.tag == .windows) {
const dir_path_w = try windows.sliceToPrefixedFileW(dir_path);
return rmdirW(dir_path_w.span());
} else {
const dir_path_c = try toPosixPath(dir_path);
return rmdirZ(&dir_path_c);
}
}
pub const rmdirC = @compileError("deprecated: renamed to rmdirZ");
/// Same as `rmdir` except the parameter is null-terminated.
pub fn rmdirZ(dir_path: [*:0]const u8) DeleteDirError!void {
if (builtin.os.tag == .windows) {
const dir_path_w = try windows.cStrToPrefixedFileW(dir_path);
return rmdirW(dir_path_w.span());
}
switch (errno(system.rmdir(dir_path))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.AccessDenied,
EBUSY => return error.FileBusy,
EFAULT => unreachable,
EINVAL => unreachable,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOTDIR => return error.NotDir,
EEXIST => return error.DirNotEmpty,
ENOTEMPTY => return error.DirNotEmpty,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
/// Windows-only. Same as `rmdir` except the parameter is WTF16 encoded.
pub fn rmdirW(dir_path_w: []const u16) DeleteDirError!void {
return windows.DeleteFile(dir_path_w, .{ .dir = std.fs.cwd().fd, .remove_dir = true }) catch |err| switch (err) {
error.IsDir => unreachable,
else => |e| return e,
};
}
pub const ChangeCurDirError = error{
AccessDenied,
FileSystem,
SymLinkLoop,
NameTooLong,
FileNotFound,
SystemResources,
NotDir,
/// On Windows, file paths must be valid Unicode.
InvalidUtf8,
} || UnexpectedError;
/// Changes the current working directory of the calling process.
/// `dir_path` is recommended to be a UTF-8 encoded string.
pub fn chdir(dir_path: []const u8) ChangeCurDirError!void {
if (builtin.os.tag == .wasi) {
@compileError("chdir is not supported in WASI");
} else if (builtin.os.tag == .windows) {
windows.SetCurrentDirectory(dir_path) catch |err| switch (err) {
error.NoDevice => return error.FileSystem,
else => |e| return e,
};
} else {
const dir_path_c = try toPosixPath(dir_path);
return chdirZ(&dir_path_c);
}
}
pub const chdirC = @compileError("deprecated: renamed to chdirZ");
/// Same as `chdir` except the parameter is null-terminated.
pub fn chdirZ(dir_path: [*:0]const u8) ChangeCurDirError!void {
if (builtin.os.tag == .windows) {
return chdir(mem.spanZ(dir_path));
}
switch (errno(system.chdir(dir_path))) {
0 => return,
EACCES => return error.AccessDenied,
EFAULT => unreachable,
EIO => return error.FileSystem,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOTDIR => return error.NotDir,
else => |err| return unexpectedErrno(err),
}
}
pub const FchdirError = error{
AccessDenied,
NotDir,
FileSystem,
} || UnexpectedError;
pub fn fchdir(dirfd: fd_t) FchdirError!void {
while (true) {
switch (errno(system.fchdir(dirfd))) {
0 => return,
EACCES => return error.AccessDenied,
EBADF => unreachable,
ENOTDIR => return error.NotDir,
EINTR => continue,
EIO => return error.FileSystem,
else => |err| return unexpectedErrno(err),
}
}
}
pub const ReadLinkError = error{
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to read value of a symbolic link relative to it.
AccessDenied,
FileSystem,
SymLinkLoop,
NameTooLong,
FileNotFound,
SystemResources,
NotDir,
InvalidUtf8,
BadPathName,
/// Windows-only. This error may occur if the opened reparse point is
/// of unsupported type.
UnsupportedReparsePointType,
} || UnexpectedError;
/// Read value of a symbolic link.
/// The return value is a slice of `out_buffer` from index 0.
pub fn readlink(file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 {
if (builtin.os.tag == .wasi) {
@compileError("readlink is not supported in WASI; use readlinkat instead");
} else if (builtin.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return readlinkW(file_path_w.span(), out_buffer);
} else {
const file_path_c = try toPosixPath(file_path);
return readlinkZ(&file_path_c, out_buffer);
}
}
pub const readlinkC = @compileError("deprecated: renamed to readlinkZ");
/// Windows-only. Same as `readlink` except `file_path` is WTF16 encoded.
/// See also `readlinkZ`.
pub fn readlinkW(file_path: []const u16, out_buffer: []u8) ReadLinkError![]u8 {
return windows.ReadLink(std.fs.cwd().fd, file_path, out_buffer);
}
/// Same as `readlink` except `file_path` is null-terminated.
pub fn readlinkZ(file_path: [*:0]const u8, out_buffer: []u8) ReadLinkError![]u8 {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.cStrToWin32PrefixedFileW(file_path);
return readlinkW(file_path_w.span(), out_buffer);
}
const rc = system.readlink(file_path, out_buffer.ptr, out_buffer.len);
switch (errno(rc)) {
0 => return out_buffer[0..@bitCast(usize, rc)],
EACCES => return error.AccessDenied,
EFAULT => unreachable,
EINVAL => unreachable,
EIO => return error.FileSystem,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOTDIR => return error.NotDir,
else => |err| return unexpectedErrno(err),
}
}
/// Similar to `readlink` except reads value of a symbolink link **relative** to `dirfd` directory handle.
/// The return value is a slice of `out_buffer` from index 0.
/// See also `readlinkatWasi`, `realinkatZ` and `realinkatW`.
pub fn readlinkat(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 {
if (builtin.os.tag == .wasi) {
return readlinkatWasi(dirfd, file_path, out_buffer);
}
if (builtin.os.tag == .windows) {
const file_path_w = try windows.sliceToPrefixedFileW(file_path);
return readlinkatW(dirfd, file_path_w.span(), out_buffer);
}
const file_path_c = try toPosixPath(file_path);
return readlinkatZ(dirfd, &file_path_c, out_buffer);
}
pub const readlinkatC = @compileError("deprecated: renamed to readlinkatZ");
/// WASI-only. Same as `readlinkat` but targets WASI.
/// See also `readlinkat`.
pub fn readlinkatWasi(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 {
var bufused: usize = undefined;
switch (wasi.path_readlink(dirfd, file_path.ptr, file_path.len, out_buffer.ptr, out_buffer.len, &bufused)) {
wasi.ESUCCESS => return out_buffer[0..bufused],
wasi.EACCES => return error.AccessDenied,
wasi.EFAULT => unreachable,
wasi.EINVAL => unreachable,
wasi.EIO => return error.FileSystem,
wasi.ELOOP => return error.SymLinkLoop,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOMEM => return error.SystemResources,
wasi.ENOTDIR => return error.NotDir,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Windows-only. Same as `readlinkat` except `file_path` is null-terminated, WTF16 encoded.
/// See also `readlinkat`.
pub fn readlinkatW(dirfd: fd_t, file_path: []const u16, out_buffer: []u8) ReadLinkError![]u8 {
return windows.ReadLink(dirfd, file_path, out_buffer);
}
/// Same as `readlinkat` except `file_path` is null-terminated.
/// See also `readlinkat`.
pub fn readlinkatZ(dirfd: fd_t, file_path: [*:0]const u8, out_buffer: []u8) ReadLinkError![]u8 {
if (builtin.os.tag == .windows) {
const file_path_w = try windows.cStrToPrefixedFileW(file_path);
return readlinkatW(dirfd, file_path_w.span(), out_buffer);
}
const rc = system.readlinkat(dirfd, file_path, out_buffer.ptr, out_buffer.len);
switch (errno(rc)) {
0 => return out_buffer[0..@bitCast(usize, rc)],
EACCES => return error.AccessDenied,
EFAULT => unreachable,
EINVAL => unreachable,
EIO => return error.FileSystem,
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOTDIR => return error.NotDir,
else => |err| return unexpectedErrno(err),
}
}
pub const SetEidError = error{
InvalidUserId,
PermissionDenied,
} || UnexpectedError;
pub const SetIdError = error{ResourceLimitReached} || SetEidError;
pub fn setuid(uid: uid_t) SetIdError!void {
switch (errno(system.setuid(uid))) {
0 => return,
EAGAIN => return error.ResourceLimitReached,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn seteuid(uid: uid_t) SetEidError!void {
switch (errno(system.seteuid(uid))) {
0 => return,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn setreuid(ruid: uid_t, euid: uid_t) SetIdError!void {
switch (errno(system.setreuid(ruid, euid))) {
0 => return,
EAGAIN => return error.ResourceLimitReached,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn setgid(gid: gid_t) SetIdError!void {
switch (errno(system.setgid(gid))) {
0 => return,
EAGAIN => return error.ResourceLimitReached,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn setegid(uid: uid_t) SetEidError!void {
switch (errno(system.setegid(uid))) {
0 => return,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
pub fn setregid(rgid: gid_t, egid: gid_t) SetIdError!void {
switch (errno(system.setregid(rgid, egid))) {
0 => return,
EAGAIN => return error.ResourceLimitReached,
EINVAL => return error.InvalidUserId,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Test whether a file descriptor refers to a terminal.
pub fn isatty(handle: fd_t) bool {
if (builtin.os.tag == .windows) {
if (isCygwinPty(handle))
return true;
var out: windows.DWORD = undefined;
return windows.kernel32.GetConsoleMode(handle, &out) != 0;
}
if (builtin.link_libc) {
return system.isatty(handle) != 0;
}
if (builtin.os.tag == .wasi) {
var statbuf: fdstat_t = undefined;
const err = system.fd_fdstat_get(handle, &statbuf);
if (err != 0) {
// errno = err;
return false;
}
// A tty is a character device that we can't seek or tell on.
if (statbuf.fs_filetype != FILETYPE_CHARACTER_DEVICE or
(statbuf.fs_rights_base & (RIGHT_FD_SEEK | RIGHT_FD_TELL)) != 0)
{
// errno = ENOTTY;
return false;
}
return true;
}
if (builtin.os.tag == .linux) {
while (true) {
var wsz: linux.winsize = undefined;
const fd = @bitCast(usize, @as(isize, handle));
switch (linux.syscall3(.ioctl, fd, linux.TIOCGWINSZ, @ptrToInt(&wsz))) {
0 => return true,
EINTR => continue,
else => return false,
}
}
}
return system.isatty(handle) != 0;
}
pub fn isCygwinPty(handle: fd_t) bool {
if (builtin.os.tag != .windows) return false;
const size = @sizeOf(windows.FILE_NAME_INFO);
var name_info_bytes align(@alignOf(windows.FILE_NAME_INFO)) = [_]u8{0} ** (size + windows.MAX_PATH);
if (windows.kernel32.GetFileInformationByHandleEx(
handle,
windows.FileNameInfo,
@ptrCast(*c_void, &name_info_bytes),
name_info_bytes.len,
) == 0) {
return false;
}
const name_info = @ptrCast(*const windows.FILE_NAME_INFO, &name_info_bytes[0]);
const name_bytes = name_info_bytes[size .. size + @as(usize, name_info.FileNameLength)];
const name_wide = mem.bytesAsSlice(u16, name_bytes);
return mem.indexOf(u16, name_wide, &[_]u16{ 'm', 's', 'y', 's', '-' }) != null or
mem.indexOf(u16, name_wide, &[_]u16{ '-', 'p', 't', 'y' }) != null;
}
pub const SocketError = error{
/// Permission to create a socket of the specified type and/or
/// pro‐tocol is denied.
PermissionDenied,
/// The implementation does not support the specified address family.
AddressFamilyNotSupported,
/// Unknown protocol, or protocol family not available.
ProtocolFamilyNotAvailable,
/// The per-process limit on the number of open file descriptors has been reached.
ProcessFdQuotaExceeded,
/// The system-wide limit on the total number of open files has been reached.
SystemFdQuotaExceeded,
/// Insufficient memory is available. The socket cannot be created until sufficient
/// resources are freed.
SystemResources,
/// The protocol type or the specified protocol is not supported within this domain.
ProtocolNotSupported,
/// The socket type is not supported by the protocol.
SocketTypeNotSupported,
} || UnexpectedError;
pub fn socket(domain: u32, socket_type: u32, protocol: u32) SocketError!socket_t {
if (builtin.os.tag == .windows) {
// NOTE: windows translates the SOCK_NONBLOCK/SOCK_CLOEXEC flags into windows-analagous operations
const filtered_sock_type = socket_type & ~@as(u32, SOCK_NONBLOCK | SOCK_CLOEXEC);
const flags: u32 = if ((socket_type & SOCK_CLOEXEC) != 0) windows.ws2_32.WSA_FLAG_NO_HANDLE_INHERIT else 0;
const rc = try windows.WSASocketW(@bitCast(i32, domain), @bitCast(i32, filtered_sock_type), @bitCast(i32, protocol), null, 0, flags);
errdefer windows.closesocket(rc) catch unreachable;
if ((socket_type & SOCK_NONBLOCK) != 0) {
var mode: c_ulong = 1; // nonblocking
if (windows.ws2_32.SOCKET_ERROR == windows.ws2_32.ioctlsocket(rc, windows.ws2_32.FIONBIO, &mode)) {
switch (windows.ws2_32.WSAGetLastError()) {
// have not identified any error codes that should be handled yet
else => unreachable,
}
}
}
return rc;
}
const have_sock_flags = comptime !std.Target.current.isDarwin();
const filtered_sock_type = if (!have_sock_flags)
socket_type & ~@as(u32, SOCK_NONBLOCK | SOCK_CLOEXEC)
else
socket_type;
const rc = system.socket(domain, filtered_sock_type, protocol);
switch (errno(rc)) {
0 => {
const fd = @intCast(fd_t, rc);
if (!have_sock_flags) {
try setSockFlags(fd, socket_type);
}
return fd;
},
EACCES => return error.PermissionDenied,
EAFNOSUPPORT => return error.AddressFamilyNotSupported,
EINVAL => return error.ProtocolFamilyNotAvailable,
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
EPROTONOSUPPORT => return error.ProtocolNotSupported,
EPROTOTYPE => return error.SocketTypeNotSupported,
else => |err| return unexpectedErrno(err),
}
}
pub fn closeSocket(sock: socket_t) void {
if (builtin.os.tag == .windows) {
windows.closesocket(sock) catch unreachable;
} else {
close(sock);
}
}
pub const BindError = error{
/// The address is protected, and the user is not the superuser.
/// For UNIX domain sockets: Search permission is denied on a component
/// of the path prefix.
AccessDenied,
/// The given address is already in use, or in the case of Internet domain sockets,
/// The port number was specified as zero in the socket
/// address structure, but, upon attempting to bind to an ephemeral port, it was
/// determined that all port numbers in the ephemeral port range are currently in
/// use. See the discussion of /proc/sys/net/ipv4/ip_local_port_range ip(7).
AddressInUse,
/// A nonexistent interface was requested or the requested address was not local.
AddressNotAvailable,
/// Too many symbolic links were encountered in resolving addr.
SymLinkLoop,
/// addr is too long.
NameTooLong,
/// A component in the directory prefix of the socket pathname does not exist.
FileNotFound,
/// Insufficient kernel memory was available.
SystemResources,
/// A component of the path prefix is not a directory.
NotDir,
/// The socket inode would reside on a read-only filesystem.
ReadOnlyFileSystem,
/// The network subsystem has failed.
NetworkSubsystemFailed,
FileDescriptorNotASocket,
AlreadyBound,
} || UnexpectedError;
/// addr is `*const T` where T is one of the sockaddr
pub fn bind(sock: socket_t, addr: *const sockaddr, len: socklen_t) BindError!void {
if (builtin.os.tag == .windows) {
const rc = windows.bind(sock, addr, len);
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable, // not initialized WSA
.WSAEACCES => return error.AccessDenied,
.WSAEADDRINUSE => return error.AddressInUse,
.WSAEADDRNOTAVAIL => return error.AddressNotAvailable,
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
.WSAEFAULT => unreachable, // invalid pointers
.WSAEINVAL => return error.AlreadyBound,
.WSAENOBUFS => return error.SystemResources,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
else => |err| return windows.unexpectedWSAError(err),
}
unreachable;
}
return;
} else {
const rc = system.bind(sock, addr, len);
switch (errno(rc)) {
0 => return,
EACCES => return error.AccessDenied,
EADDRINUSE => return error.AddressInUse,
EBADF => unreachable, // always a race condition if this error is returned
EINVAL => unreachable, // invalid parameters
ENOTSOCK => unreachable, // invalid `sockfd`
EADDRNOTAVAIL => return error.AddressNotAvailable,
EFAULT => unreachable, // invalid `addr` pointer
ELOOP => return error.SymLinkLoop,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOTDIR => return error.NotDir,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
unreachable;
}
const ListenError = error{
/// Another socket is already listening on the same port.
/// For Internet domain sockets, the socket referred to by sockfd had not previously
/// been bound to an address and, upon attempting to bind it to an ephemeral port, it
/// was determined that all port numbers in the ephemeral port range are currently in
/// use. See the discussion of /proc/sys/net/ipv4/ip_local_port_range in ip(7).
AddressInUse,
/// The file descriptor sockfd does not refer to a socket.
FileDescriptorNotASocket,
/// The socket is not of a type that supports the listen() operation.
OperationNotSupported,
/// The network subsystem has failed.
NetworkSubsystemFailed,
/// Ran out of system resources
/// On Windows it can either run out of socket descriptors or buffer space
SystemResources,
/// Already connected
AlreadyConnected,
/// Socket has not been bound yet
SocketNotBound,
} || UnexpectedError;
pub fn listen(sock: socket_t, backlog: u31) ListenError!void {
if (builtin.os.tag == .windows) {
const rc = windows.listen(sock, backlog);
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable, // not initialized WSA
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAEADDRINUSE => return error.AddressInUse,
.WSAEISCONN => return error.AlreadyConnected,
.WSAEINVAL => return error.SocketNotBound,
.WSAEMFILE, .WSAENOBUFS => return error.SystemResources,
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
.WSAEOPNOTSUPP => return error.OperationNotSupported,
.WSAEINPROGRESS => unreachable,
else => |err| return windows.unexpectedWSAError(err),
}
}
return;
} else {
const rc = system.listen(sock, backlog);
switch (errno(rc)) {
0 => return,
EADDRINUSE => return error.AddressInUse,
EBADF => unreachable,
ENOTSOCK => return error.FileDescriptorNotASocket,
EOPNOTSUPP => return error.OperationNotSupported,
else => |err| return unexpectedErrno(err),
}
}
}
pub const AcceptError = error{
ConnectionAborted,
/// The file descriptor sockfd does not refer to a socket.
FileDescriptorNotASocket,
/// The per-process limit on the number of open file descriptors has been reached.
ProcessFdQuotaExceeded,
/// The system-wide limit on the total number of open files has been reached.
SystemFdQuotaExceeded,
/// Not enough free memory. This often means that the memory allocation is limited
/// by the socket buffer limits, not by the system memory.
SystemResources,
/// Socket is not listening for new connections.
SocketNotListening,
ProtocolFailure,
/// Firewall rules forbid connection.
BlockedByFirewall,
/// This error occurs when no global event loop is configured,
/// and accepting from the socket would block.
WouldBlock,
/// Permission to create a socket of the specified type and/or
/// protocol is denied.
PermissionDenied,
/// An incoming connection was indicated, but was subsequently terminated by the
/// remote peer prior to accepting the call.
ConnectionResetByPeer,
/// The network subsystem has failed.
NetworkSubsystemFailed,
/// The referenced socket is not a type that supports connection-oriented service.
OperationNotSupported,
} || UnexpectedError;
/// Accept a connection on a socket.
/// If `sockfd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
pub fn accept(
/// This argument is a socket that has been created with `socket`, bound to a local address
/// with `bind`, and is listening for connections after a `listen`.
sock: socket_t,
/// This argument is a pointer to a sockaddr structure. This structure is filled in with the
/// address of the peer socket, as known to the communications layer. The exact format of the
/// address returned addr is determined by the socket's address family (see `socket` and the
/// respective protocol man pages).
addr: ?*sockaddr,
/// This argument is a value-result argument: the caller must initialize it to contain the
/// size (in bytes) of the structure pointed to by addr; on return it will contain the actual size
/// of the peer address.
///
/// The returned address is truncated if the buffer provided is too small; in this case, `addr_size`
/// will return a value greater than was supplied to the call.
addr_size: ?*socklen_t,
/// The following values can be bitwise ORed in flags to obtain different behavior:
/// * `SOCK_NONBLOCK` - Set the `O_NONBLOCK` file status flag on the open file description (see `open`)
/// referred to by the new file descriptor. Using this flag saves extra calls to `fcntl` to achieve
/// the same result.
/// * `SOCK_CLOEXEC` - Set the close-on-exec (`FD_CLOEXEC`) flag on the new file descriptor. See the
/// description of the `O_CLOEXEC` flag in `open` for reasons why this may be useful.
flags: u32,
) AcceptError!socket_t {
const have_accept4 = comptime !(std.Target.current.isDarwin() or builtin.os.tag == .windows);
assert(0 == (flags & ~@as(u32, SOCK_NONBLOCK | SOCK_CLOEXEC))); // Unsupported flag(s)
const accepted_sock = while (true) {
const rc = if (have_accept4)
system.accept4(sock, addr, addr_size, flags)
else if (builtin.os.tag == .windows)
windows.accept(sock, addr, addr_size)
else
system.accept(sock, addr, addr_size);
if (builtin.os.tag == .windows) {
if (rc == windows.ws2_32.INVALID_SOCKET) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable, // not initialized WSA
.WSAECONNRESET => return error.ConnectionResetByPeer,
.WSAEFAULT => unreachable,
.WSAEINVAL => return error.SocketNotListening,
.WSAEMFILE => return error.ProcessFdQuotaExceeded,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAENOBUFS => return error.FileDescriptorNotASocket,
.WSAEOPNOTSUPP => return error.OperationNotSupported,
.WSAEWOULDBLOCK => return error.WouldBlock,
else => |err| return windows.unexpectedWSAError(err),
}
} else {
break rc;
}
} else {
switch (errno(rc)) {
0 => {
break @intCast(socket_t, rc);
},
EINTR => continue,
EAGAIN => return error.WouldBlock,
EBADF => unreachable, // always a race condition
ECONNABORTED => return error.ConnectionAborted,
EFAULT => unreachable,
EINVAL => return error.SocketNotListening,
ENOTSOCK => unreachable,
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
EOPNOTSUPP => unreachable,
EPROTO => return error.ProtocolFailure,
EPERM => return error.BlockedByFirewall,
else => |err| return unexpectedErrno(err),
}
}
} else unreachable;
if (!have_accept4) {
try setSockFlags(accepted_sock, flags);
}
return accepted_sock;
}
pub const EpollCreateError = error{
/// The per-user limit on the number of epoll instances imposed by
/// /proc/sys/fs/epoll/max_user_instances was encountered. See epoll(7) for further
/// details.
/// Or, The per-process limit on the number of open file descriptors has been reached.
ProcessFdQuotaExceeded,
/// The system-wide limit on the total number of open files has been reached.
SystemFdQuotaExceeded,
/// There was insufficient memory to create the kernel object.
SystemResources,
} || UnexpectedError;
pub fn epoll_create1(flags: u32) EpollCreateError!i32 {
const rc = system.epoll_create1(flags);
switch (errno(rc)) {
0 => return @intCast(i32, rc),
else => |err| return unexpectedErrno(err),
EINVAL => unreachable,
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
ENOMEM => return error.SystemResources,
}
}
pub const EpollCtlError = error{
/// op was EPOLL_CTL_ADD, and the supplied file descriptor fd is already registered
/// with this epoll instance.
FileDescriptorAlreadyPresentInSet,
/// fd refers to an epoll instance and this EPOLL_CTL_ADD operation would result in a
/// circular loop of epoll instances monitoring one another.
OperationCausesCircularLoop,
/// op was EPOLL_CTL_MOD or EPOLL_CTL_DEL, and fd is not registered with this epoll
/// instance.
FileDescriptorNotRegistered,
/// There was insufficient memory to handle the requested op control operation.
SystemResources,
/// The limit imposed by /proc/sys/fs/epoll/max_user_watches was encountered while
/// trying to register (EPOLL_CTL_ADD) a new file descriptor on an epoll instance.
/// See epoll(7) for further details.
UserResourceLimitReached,
/// The target file fd does not support epoll. This error can occur if fd refers to,
/// for example, a regular file or a directory.
FileDescriptorIncompatibleWithEpoll,
} || UnexpectedError;
pub fn epoll_ctl(epfd: i32, op: u32, fd: i32, event: ?*epoll_event) EpollCtlError!void {
const rc = system.epoll_ctl(epfd, op, fd, event);
switch (errno(rc)) {
0 => return,
else => |err| return unexpectedErrno(err),
EBADF => unreachable, // always a race condition if this happens
EEXIST => return error.FileDescriptorAlreadyPresentInSet,
EINVAL => unreachable,
ELOOP => return error.OperationCausesCircularLoop,
ENOENT => return error.FileDescriptorNotRegistered,
ENOMEM => return error.SystemResources,
ENOSPC => return error.UserResourceLimitReached,
EPERM => return error.FileDescriptorIncompatibleWithEpoll,
}
}
/// Waits for an I/O event on an epoll file descriptor.
/// Returns the number of file descriptors ready for the requested I/O,
/// or zero if no file descriptor became ready during the requested timeout milliseconds.
pub fn epoll_wait(epfd: i32, events: []epoll_event, timeout: i32) usize {
while (true) {
// TODO get rid of the @intCast
const rc = system.epoll_wait(epfd, events.ptr, @intCast(u32, events.len), timeout);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EBADF => unreachable,
EFAULT => unreachable,
EINVAL => unreachable,
else => unreachable,
}
}
}
pub const EventFdError = error{
SystemResources,
ProcessFdQuotaExceeded,
SystemFdQuotaExceeded,
} || UnexpectedError;
pub fn eventfd(initval: u32, flags: u32) EventFdError!i32 {
const rc = system.eventfd(initval, flags);
switch (errno(rc)) {
0 => return @intCast(i32, rc),
else => |err| return unexpectedErrno(err),
EINVAL => unreachable, // invalid parameters
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
ENODEV => return error.SystemResources,
ENOMEM => return error.SystemResources,
}
}
pub const GetSockNameError = error{
/// Insufficient resources were available in the system to perform the operation.
SystemResources,
/// The network subsystem has failed.
NetworkSubsystemFailed,
/// Socket hasn't been bound yet
SocketNotBound,
FileDescriptorNotASocket,
} || UnexpectedError;
pub fn getsockname(sock: socket_t, addr: *sockaddr, addrlen: *socklen_t) GetSockNameError!void {
if (builtin.os.tag == .windows) {
const rc = windows.getsockname(sock, addr, addrlen);
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAEFAULT => unreachable, // addr or addrlen have invalid pointers or addrlen points to an incorrect value
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
.WSAEINVAL => return error.SocketNotBound,
else => |err| return windows.unexpectedWSAError(err),
}
}
return;
} else {
const rc = system.getsockname(sock, addr, addrlen);
switch (errno(rc)) {
0 => return,
else => |err| return unexpectedErrno(err),
EBADF => unreachable, // always a race condition
EFAULT => unreachable,
EINVAL => unreachable, // invalid parameters
ENOTSOCK => return error.FileDescriptorNotASocket,
ENOBUFS => return error.SystemResources,
}
}
}
pub const ConnectError = error{
/// For UNIX domain sockets, which are identified by pathname: Write permission is denied on the socket
/// file, or search permission is denied for one of the directories in the path prefix.
/// or
/// The user tried to connect to a broadcast address without having the socket broadcast flag enabled or
/// the connection request failed because of a local firewall rule.
PermissionDenied,
/// Local address is already in use.
AddressInUse,
/// (Internet domain sockets) The socket referred to by sockfd had not previously been bound to an
/// address and, upon attempting to bind it to an ephemeral port, it was determined that all port numbers
/// in the ephemeral port range are currently in use. See the discussion of
/// /proc/sys/net/ipv4/ip_local_port_range in ip(7).
AddressNotAvailable,
/// The passed address didn't have the correct address family in its sa_family field.
AddressFamilyNotSupported,
/// Insufficient entries in the routing cache.
SystemResources,
/// A connect() on a stream socket found no one listening on the remote address.
ConnectionRefused,
/// Network is unreachable.
NetworkUnreachable,
/// Timeout while attempting connection. The server may be too busy to accept new connections. Note
/// that for IP sockets the timeout may be very long when syncookies are enabled on the server.
ConnectionTimedOut,
/// This error occurs when no global event loop is configured,
/// and connecting to the socket would block.
WouldBlock,
/// The given path for the unix socket does not exist.
FileNotFound,
} || UnexpectedError;
/// Initiate a connection on a socket.
/// If `sockfd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN or EINPROGRESS is received.
pub fn connect(sock: socket_t, sock_addr: *const sockaddr, len: socklen_t) ConnectError!void {
if (builtin.os.tag == .windows) {
const rc = windows.ws2_32.connect(sock, sock_addr, @intCast(i32, len));
if (rc == 0) return;
switch (windows.ws2_32.WSAGetLastError()) {
.WSAEADDRINUSE => return error.AddressInUse,
.WSAEADDRNOTAVAIL => return error.AddressNotAvailable,
.WSAECONNREFUSED => return error.ConnectionRefused,
.WSAETIMEDOUT => return error.ConnectionTimedOut,
.WSAEHOSTUNREACH // TODO: should we return NetworkUnreachable in this case as well?
, .WSAENETUNREACH => return error.NetworkUnreachable,
.WSAEFAULT => unreachable,
.WSAEINVAL => unreachable,
.WSAEISCONN => unreachable,
.WSAENOTSOCK => unreachable,
.WSAEWOULDBLOCK => unreachable,
.WSAEACCES => unreachable,
.WSAENOBUFS => return error.SystemResources,
.WSAEAFNOSUPPORT => return error.AddressFamilyNotSupported,
else => |err| return windows.unexpectedWSAError(err),
}
return;
}
while (true) {
switch (errno(system.connect(sock, sock_addr, len))) {
0 => return,
EACCES => return error.PermissionDenied,
EPERM => return error.PermissionDenied,
EADDRINUSE => return error.AddressInUse,
EADDRNOTAVAIL => return error.AddressNotAvailable,
EAFNOSUPPORT => return error.AddressFamilyNotSupported,
EAGAIN, EINPROGRESS => return error.WouldBlock,
EALREADY => unreachable, // The socket is nonblocking and a previous connection attempt has not yet been completed.
EBADF => unreachable, // sockfd is not a valid open file descriptor.
ECONNREFUSED => return error.ConnectionRefused,
EFAULT => unreachable, // The socket structure address is outside the user's address space.
EINTR => continue,
EISCONN => unreachable, // The socket is already connected.
ENETUNREACH => return error.NetworkUnreachable,
ENOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket.
EPROTOTYPE => unreachable, // The socket type does not support the requested communications protocol.
ETIMEDOUT => return error.ConnectionTimedOut,
ENOENT => return error.FileNotFound, // Returned when socket is AF_UNIX and the given path does not exist.
else => |err| return unexpectedErrno(err),
}
}
}
pub fn getsockoptError(sockfd: fd_t) ConnectError!void {
var err_code: u32 = undefined;
var size: u32 = @sizeOf(u32);
const rc = system.getsockopt(sockfd, SOL_SOCKET, SO_ERROR, @ptrCast([*]u8, &err_code), &size);
assert(size == 4);
switch (errno(rc)) {
0 => switch (err_code) {
0 => return,
EACCES => return error.PermissionDenied,
EPERM => return error.PermissionDenied,
EADDRINUSE => return error.AddressInUse,
EADDRNOTAVAIL => return error.AddressNotAvailable,
EAFNOSUPPORT => return error.AddressFamilyNotSupported,
EAGAIN => return error.SystemResources,
EALREADY => unreachable, // The socket is nonblocking and a previous connection attempt has not yet been completed.
EBADF => unreachable, // sockfd is not a valid open file descriptor.
ECONNREFUSED => return error.ConnectionRefused,
EFAULT => unreachable, // The socket structure address is outside the user's address space.
EISCONN => unreachable, // The socket is already connected.
ENETUNREACH => return error.NetworkUnreachable,
ENOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket.
EPROTOTYPE => unreachable, // The socket type does not support the requested communications protocol.
ETIMEDOUT => return error.ConnectionTimedOut,
else => |err| return unexpectedErrno(err),
},
EBADF => unreachable, // The argument sockfd is not a valid file descriptor.
EFAULT => unreachable, // The address pointed to by optval or optlen is not in a valid part of the process address space.
EINVAL => unreachable,
ENOPROTOOPT => unreachable, // The option is unknown at the level indicated.
ENOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket.
else => |err| return unexpectedErrno(err),
}
}
pub const WaitPidResult = struct {
pid: pid_t,
status: u32,
};
pub fn waitpid(pid: pid_t, flags: u32) WaitPidResult {
const Status = if (builtin.link_libc) c_uint else u32;
var status: Status = undefined;
while (true) {
const rc = system.waitpid(pid, &status, flags);
switch (errno(rc)) {
0 => return .{
.pid = @intCast(pid_t, rc),
.status = @bitCast(u32, status),
},
EINTR => continue,
ECHILD => unreachable, // The process specified does not exist. It would be a race condition to handle this error.
EINVAL => unreachable, // Invalid flags.
else => unreachable,
}
}
}
pub const Stat = if (builtin.link_libc)
system.libc_stat
else
system.kernel_stat;
pub const FStatError = error{
SystemResources,
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to get its filestat information.
AccessDenied,
} || UnexpectedError;
/// Return information about a file descriptor.
pub fn fstat(fd: fd_t) FStatError!Stat {
if (builtin.os.tag == .wasi) {
var stat: wasi.filestat_t = undefined;
switch (wasi.fd_filestat_get(fd, &stat)) {
wasi.ESUCCESS => return Stat.fromFilestat(stat),
wasi.EINVAL => unreachable,
wasi.EBADF => unreachable, // Always a race condition.
wasi.ENOMEM => return error.SystemResources,
wasi.EACCES => return error.AccessDenied,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .windows) {
@compileError("fstat is not yet implemented on Windows");
}
var stat: Stat = undefined;
switch (errno(system.fstat(fd, &stat))) {
0 => return stat,
EINVAL => unreachable,
EBADF => unreachable, // Always a race condition.
ENOMEM => return error.SystemResources,
EACCES => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
pub const FStatAtError = FStatError || error{ NameTooLong, FileNotFound };
/// Similar to `fstat`, but returns stat of a resource pointed to by `pathname`
/// which is relative to `dirfd` handle.
/// See also `fstatatZ` and `fstatatWasi`.
pub fn fstatat(dirfd: fd_t, pathname: []const u8, flags: u32) FStatAtError!Stat {
if (builtin.os.tag == .wasi) {
return fstatatWasi(dirfd, pathname, flags);
} else if (builtin.os.tag == .windows) {
@compileError("fstatat is not yet implemented on Windows");
} else {
const pathname_c = try toPosixPath(pathname);
return fstatatZ(dirfd, &pathname_c, flags);
}
}
pub const fstatatC = @compileError("deprecated: renamed to fstatatZ");
/// WASI-only. Same as `fstatat` but targeting WASI.
/// See also `fstatat`.
pub fn fstatatWasi(dirfd: fd_t, pathname: []const u8, flags: u32) FStatAtError!Stat {
var stat: wasi.filestat_t = undefined;
switch (wasi.path_filestat_get(dirfd, flags, pathname.ptr, pathname.len, &stat)) {
wasi.ESUCCESS => return Stat.fromFilestat(stat),
wasi.EINVAL => unreachable,
wasi.EBADF => unreachable, // Always a race condition.
wasi.ENOMEM => return error.SystemResources,
wasi.EACCES => return error.AccessDenied,
wasi.EFAULT => unreachable,
wasi.ENAMETOOLONG => return error.NameTooLong,
wasi.ENOENT => return error.FileNotFound,
wasi.ENOTDIR => return error.FileNotFound,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Same as `fstatat` but `pathname` is null-terminated.
/// See also `fstatat`.
pub fn fstatatZ(dirfd: fd_t, pathname: [*:0]const u8, flags: u32) FStatAtError!Stat {
var stat: Stat = undefined;
switch (errno(system.fstatat(dirfd, pathname, &stat, flags))) {
0 => return stat,
EINVAL => unreachable,
EBADF => unreachable, // Always a race condition.
ENOMEM => return error.SystemResources,
EACCES => return error.AccessDenied,
EFAULT => unreachable,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOTDIR => return error.FileNotFound,
else => |err| return unexpectedErrno(err),
}
}
pub const KQueueError = error{
/// The per-process limit on the number of open file descriptors has been reached.
ProcessFdQuotaExceeded,
/// The system-wide limit on the total number of open files has been reached.
SystemFdQuotaExceeded,
} || UnexpectedError;
pub fn kqueue() KQueueError!i32 {
const rc = system.kqueue();
switch (errno(rc)) {
0 => return @intCast(i32, rc),
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
else => |err| return unexpectedErrno(err),
}
}
pub const KEventError = error{
/// The process does not have permission to register a filter.
AccessDenied,
/// The event could not be found to be modified or deleted.
EventNotFound,
/// No memory was available to register the event.
SystemResources,
/// The specified process to attach to does not exist.
ProcessNotFound,
/// changelist or eventlist had too many items on it.
/// TODO remove this possibility
Overflow,
};
pub fn kevent(
kq: i32,
changelist: []const Kevent,
eventlist: []Kevent,
timeout: ?*const timespec,
) KEventError!usize {
while (true) {
const rc = system.kevent(
kq,
changelist.ptr,
try math.cast(c_int, changelist.len),
eventlist.ptr,
try math.cast(c_int, eventlist.len),
timeout,
);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EACCES => return error.AccessDenied,
EFAULT => unreachable,
EBADF => unreachable, // Always a race condition.
EINTR => continue,
EINVAL => unreachable,
ENOENT => return error.EventNotFound,
ENOMEM => return error.SystemResources,
ESRCH => return error.ProcessNotFound,
else => unreachable,
}
}
}
pub const INotifyInitError = error{
ProcessFdQuotaExceeded,
SystemFdQuotaExceeded,
SystemResources,
} || UnexpectedError;
/// initialize an inotify instance
pub fn inotify_init1(flags: u32) INotifyInitError!i32 {
const rc = system.inotify_init1(flags);
switch (errno(rc)) {
0 => return @intCast(i32, rc),
EINVAL => unreachable,
EMFILE => return error.ProcessFdQuotaExceeded,
ENFILE => return error.SystemFdQuotaExceeded,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
pub const INotifyAddWatchError = error{
AccessDenied,
NameTooLong,
FileNotFound,
SystemResources,
UserResourceLimitReached,
} || UnexpectedError;
/// add a watch to an initialized inotify instance
pub fn inotify_add_watch(inotify_fd: i32, pathname: []const u8, mask: u32) INotifyAddWatchError!i32 {
const pathname_c = try toPosixPath(pathname);
return inotify_add_watchZ(inotify_fd, &pathname_c, mask);
}
pub const inotify_add_watchC = @compileError("deprecated: renamed to inotify_add_watchZ");
/// Same as `inotify_add_watch` except pathname is null-terminated.
pub fn inotify_add_watchZ(inotify_fd: i32, pathname: [*:0]const u8, mask: u32) INotifyAddWatchError!i32 {
const rc = system.inotify_add_watch(inotify_fd, pathname, mask);
switch (errno(rc)) {
0 => return @intCast(i32, rc),
EACCES => return error.AccessDenied,
EBADF => unreachable,
EFAULT => unreachable,
EINVAL => unreachable,
ENAMETOOLONG => return error.NameTooLong,
ENOENT => return error.FileNotFound,
ENOMEM => return error.SystemResources,
ENOSPC => return error.UserResourceLimitReached,
else => |err| return unexpectedErrno(err),
}
}
/// remove an existing watch from an inotify instance
pub fn inotify_rm_watch(inotify_fd: i32, wd: i32) void {
switch (errno(system.inotify_rm_watch(inotify_fd, wd))) {
0 => return,
EBADF => unreachable,
EINVAL => unreachable,
else => unreachable,
}
}
pub const MProtectError = error{
/// The memory cannot be given the specified access. This can happen, for example, if you
/// mmap(2) a file to which you have read-only access, then ask mprotect() to mark it
/// PROT_WRITE.
AccessDenied,
/// Changing the protection of a memory region would result in the total number of map‐
/// pings with distinct attributes (e.g., read versus read/write protection) exceeding the
/// allowed maximum. (For example, making the protection of a range PROT_READ in the mid‐
/// dle of a region currently protected as PROT_READ|PROT_WRITE would result in three map‐
/// pings: two read/write mappings at each end and a read-only mapping in the middle.)
OutOfMemory,
} || UnexpectedError;
/// `memory.len` must be page-aligned.
pub fn mprotect(memory: []align(mem.page_size) u8, protection: u32) MProtectError!void {
assert(mem.isAligned(memory.len, mem.page_size));
switch (errno(system.mprotect(memory.ptr, memory.len, protection))) {
0 => return,
EINVAL => unreachable,
EACCES => return error.AccessDenied,
ENOMEM => return error.OutOfMemory,
else => |err| return unexpectedErrno(err),
}
}
pub const ForkError = error{SystemResources} || UnexpectedError;
pub fn fork() ForkError!pid_t {
const rc = system.fork();
switch (errno(rc)) {
0 => return @intCast(pid_t, rc),
EAGAIN => return error.SystemResources,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
pub const MMapError = error{
/// The underlying filesystem of the specified file does not support memory mapping.
MemoryMappingNotSupported,
/// A file descriptor refers to a non-regular file. Or a file mapping was requested,
/// but the file descriptor is not open for reading. Or `MAP_SHARED` was requested
/// and `PROT_WRITE` is set, but the file descriptor is not open in `O_RDWR` mode.
/// Or `PROT_WRITE` is set, but the file is append-only.
AccessDenied,
/// The `prot` argument asks for `PROT_EXEC` but the mapped area belongs to a file on
/// a filesystem that was mounted no-exec.
PermissionDenied,
LockedMemoryLimitExceeded,
OutOfMemory,
} || UnexpectedError;
/// Map files or devices into memory.
/// `length` does not need to be aligned.
/// Use of a mapped region can result in these signals:
/// * SIGSEGV - Attempted write into a region mapped as read-only.
/// * SIGBUS - Attempted access to a portion of the buffer that does not correspond to the file
pub fn mmap(
ptr: ?[*]align(mem.page_size) u8,
length: usize,
prot: u32,
flags: u32,
fd: fd_t,
offset: u64,
) MMapError![]align(mem.page_size) u8 {
const err = if (builtin.link_libc) blk: {
const rc = std.c.mmap(ptr, length, prot, flags, fd, offset);
if (rc != std.c.MAP_FAILED) return @ptrCast([*]align(mem.page_size) u8, @alignCast(mem.page_size, rc))[0..length];
break :blk @intCast(usize, system._errno().*);
} else blk: {
const rc = system.mmap(ptr, length, prot, flags, fd, offset);
const err = errno(rc);
if (err == 0) return @intToPtr([*]align(mem.page_size) u8, rc)[0..length];
break :blk err;
};
switch (err) {
ETXTBSY => return error.AccessDenied,
EACCES => return error.AccessDenied,
EPERM => return error.PermissionDenied,
EAGAIN => return error.LockedMemoryLimitExceeded,
EBADF => unreachable, // Always a race condition.
EOVERFLOW => unreachable, // The number of pages used for length + offset would overflow.
ENODEV => return error.MemoryMappingNotSupported,
EINVAL => unreachable, // Invalid parameters to mmap()
ENOMEM => return error.OutOfMemory,
else => return unexpectedErrno(err),
}
}
/// Deletes the mappings for the specified address range, causing
/// further references to addresses within the range to generate invalid memory references.
/// Note that while POSIX allows unmapping a region in the middle of an existing mapping,
/// Zig's munmap function does not, for two reasons:
/// * It violates the Zig principle that resource deallocation must succeed.
/// * The Windows function, VirtualFree, has this restriction.
pub fn munmap(memory: []align(mem.page_size) u8) void {
switch (errno(system.munmap(memory.ptr, memory.len))) {
0 => return,
EINVAL => unreachable, // Invalid parameters.
ENOMEM => unreachable, // Attempted to unmap a region in the middle of an existing mapping.
else => unreachable,
}
}
pub const AccessError = error{
PermissionDenied,
FileNotFound,
NameTooLong,
InputOutput,
SystemResources,
BadPathName,
FileBusy,
SymLinkLoop,
ReadOnlyFileSystem,
/// On Windows, file paths must be valid Unicode.
InvalidUtf8,
} || UnexpectedError;
/// check user's permissions for a file
/// TODO currently this assumes `mode` is `F_OK` on Windows.
pub fn access(path: []const u8, mode: u32) AccessError!void {
if (builtin.os.tag == .windows) {
const path_w = try windows.sliceToPrefixedFileW(path);
_ = try windows.GetFileAttributesW(path_w.span().ptr);
return;
}
const path_c = try toPosixPath(path);
return accessZ(&path_c, mode);
}
pub const accessC = @compileError("Deprecated in favor of `accessZ`");
/// Same as `access` except `path` is null-terminated.
pub fn accessZ(path: [*:0]const u8, mode: u32) AccessError!void {
if (builtin.os.tag == .windows) {
const path_w = try windows.cStrToPrefixedFileW(path);
_ = try windows.GetFileAttributesW(path_w.span().ptr);
return;
}
switch (errno(system.access(path, mode))) {
0 => return,
EACCES => return error.PermissionDenied,
EROFS => return error.ReadOnlyFileSystem,
ELOOP => return error.SymLinkLoop,
ETXTBSY => return error.FileBusy,
ENOTDIR => return error.FileNotFound,
ENOENT => return error.FileNotFound,
ENAMETOOLONG => return error.NameTooLong,
EINVAL => unreachable,
EFAULT => unreachable,
EIO => return error.InputOutput,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
/// Call from Windows-specific code if you already have a UTF-16LE encoded, null terminated string.
/// Otherwise use `access` or `accessC`.
/// TODO currently this ignores `mode`.
pub fn accessW(path: [*:0]const u16, mode: u32) windows.GetFileAttributesError!void {
const ret = try windows.GetFileAttributesW(path);
if (ret != windows.INVALID_FILE_ATTRIBUTES) {
return;
}
switch (windows.kernel32.GetLastError()) {
.FILE_NOT_FOUND => return error.FileNotFound,
.PATH_NOT_FOUND => return error.FileNotFound,
.ACCESS_DENIED => return error.PermissionDenied,
else => |err| return windows.unexpectedError(err),
}
}
/// Check user's permissions for a file, based on an open directory handle.
/// TODO currently this ignores `mode` and `flags` on Windows.
pub fn faccessat(dirfd: fd_t, path: []const u8, mode: u32, flags: u32) AccessError!void {
if (builtin.os.tag == .windows) {
const path_w = try windows.sliceToPrefixedFileW(path);
return faccessatW(dirfd, path_w.span().ptr, mode, flags);
}
const path_c = try toPosixPath(path);
return faccessatZ(dirfd, &path_c, mode, flags);
}
/// Same as `faccessat` except the path parameter is null-terminated.
pub fn faccessatZ(dirfd: fd_t, path: [*:0]const u8, mode: u32, flags: u32) AccessError!void {
if (builtin.os.tag == .windows) {
const path_w = try windows.cStrToPrefixedFileW(path);
return faccessatW(dirfd, path_w.span().ptr, mode, flags);
}
switch (errno(system.faccessat(dirfd, path, mode, flags))) {
0 => return,
EACCES => return error.PermissionDenied,
EROFS => return error.ReadOnlyFileSystem,
ELOOP => return error.SymLinkLoop,
ETXTBSY => return error.FileBusy,
ENOTDIR => return error.FileNotFound,
ENOENT => return error.FileNotFound,
ENAMETOOLONG => return error.NameTooLong,
EINVAL => unreachable,
EFAULT => unreachable,
EIO => return error.InputOutput,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
/// Same as `faccessat` except asserts the target is Windows and the path parameter
/// is NtDll-prefixed, null-terminated, WTF-16 encoded.
/// TODO currently this ignores `mode` and `flags`
pub fn faccessatW(dirfd: fd_t, sub_path_w: [*:0]const u16, mode: u32, flags: u32) AccessError!void {
if (sub_path_w[0] == '.' and sub_path_w[1] == 0) {
return;
}
if (sub_path_w[0] == '.' and sub_path_w[1] == '.' and sub_path_w[2] == 0) {
return;
}
const path_len_bytes = math.cast(u16, mem.lenZ(sub_path_w) * 2) catch |err| switch (err) {
error.Overflow => return error.NameTooLong,
};
var nt_name = windows.UNICODE_STRING{
.Length = path_len_bytes,
.MaximumLength = path_len_bytes,
.Buffer = @intToPtr([*]u16, @ptrToInt(sub_path_w)),
};
var attr = windows.OBJECT_ATTRIBUTES{
.Length = @sizeOf(windows.OBJECT_ATTRIBUTES),
.RootDirectory = if (std.fs.path.isAbsoluteWindowsW(sub_path_w)) null else dirfd,
.Attributes = 0, // Note we do not use OBJ_CASE_INSENSITIVE here.
.ObjectName = &nt_name,
.SecurityDescriptor = null,
.SecurityQualityOfService = null,
};
var basic_info: windows.FILE_BASIC_INFORMATION = undefined;
switch (windows.ntdll.NtQueryAttributesFile(&attr, &basic_info)) {
.SUCCESS => return,
.OBJECT_NAME_NOT_FOUND => return error.FileNotFound,
.OBJECT_PATH_NOT_FOUND => return error.FileNotFound,
.INVALID_PARAMETER => unreachable,
.ACCESS_DENIED => return error.PermissionDenied,
.OBJECT_PATH_SYNTAX_BAD => unreachable,
else => |rc| return windows.unexpectedStatus(rc),
}
}
pub const PipeError = error{
SystemFdQuotaExceeded,
ProcessFdQuotaExceeded,
} || UnexpectedError;
/// Creates a unidirectional data channel that can be used for interprocess communication.
pub fn pipe() PipeError![2]fd_t {
var fds: [2]fd_t = undefined;
switch (errno(system.pipe(&fds))) {
0 => return fds,
EINVAL => unreachable, // Invalid parameters to pipe()
EFAULT => unreachable, // Invalid fds pointer
ENFILE => return error.SystemFdQuotaExceeded,
EMFILE => return error.ProcessFdQuotaExceeded,
else => |err| return unexpectedErrno(err),
}
}
pub fn pipe2(flags: u32) PipeError![2]fd_t {
if (comptime std.Target.current.isDarwin()) {
var fds: [2]fd_t = try pipe();
if (flags == 0) return fds;
errdefer {
close(fds[0]);
close(fds[1]);
}
for (fds) |fd| switch (errno(system.fcntl(fd, F_SETFL, flags))) {
0 => {},
EINVAL => unreachable, // Invalid flags
EBADF => unreachable, // Always a race condition
else => |err| return unexpectedErrno(err),
};
return fds;
}
var fds: [2]fd_t = undefined;
switch (errno(system.pipe2(&fds, flags))) {
0 => return fds,
EINVAL => unreachable, // Invalid flags
EFAULT => unreachable, // Invalid fds pointer
ENFILE => return error.SystemFdQuotaExceeded,
EMFILE => return error.ProcessFdQuotaExceeded,
else => |err| return unexpectedErrno(err),
}
}
pub const SysCtlError = error{
PermissionDenied,
SystemResources,
NameTooLong,
UnknownName,
} || UnexpectedError;
pub fn sysctl(
name: []const c_int,
oldp: ?*c_void,
oldlenp: ?*usize,
newp: ?*c_void,
newlen: usize,
) SysCtlError!void {
if (builtin.os.tag == .wasi) {
@panic("unsupported");
}
const name_len = math.cast(c_uint, name.len) catch return error.NameTooLong;
switch (errno(system.sysctl(name.ptr, name_len, oldp, oldlenp, newp, newlen))) {
0 => return,
EFAULT => unreachable,
EPERM => return error.PermissionDenied,
ENOMEM => return error.SystemResources,
ENOENT => return error.UnknownName,
else => |err| return unexpectedErrno(err),
}
}
pub const sysctlbynameC = @compileError("deprecated: renamed to sysctlbynameZ");
pub fn sysctlbynameZ(
name: [*:0]const u8,
oldp: ?*c_void,
oldlenp: ?*usize,
newp: ?*c_void,
newlen: usize,
) SysCtlError!void {
if (builtin.os.tag == .wasi) {
@panic("unsupported");
}
switch (errno(system.sysctlbyname(name, oldp, oldlenp, newp, newlen))) {
0 => return,
EFAULT => unreachable,
EPERM => return error.PermissionDenied,
ENOMEM => return error.SystemResources,
ENOENT => return error.UnknownName,
else => |err| return unexpectedErrno(err),
}
}
pub fn gettimeofday(tv: ?*timeval, tz: ?*timezone) void {
switch (errno(system.gettimeofday(tv, tz))) {
0 => return,
EINVAL => unreachable,
else => unreachable,
}
}
pub const SeekError = error{
Unseekable,
/// In WASI, this error may occur when the file descriptor does
/// not hold the required rights to seek on it.
AccessDenied,
} || UnexpectedError;
/// Repositions read/write file offset relative to the beginning.
pub fn lseek_SET(fd: fd_t, offset: u64) SeekError!void {
if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) {
var result: u64 = undefined;
switch (errno(system.llseek(fd, offset, &result, SEEK_SET))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .windows) {
return windows.SetFilePointerEx_BEGIN(fd, offset);
}
if (builtin.os.tag == .wasi) {
var new_offset: wasi.filesize_t = undefined;
switch (wasi.fd_seek(fd, @bitCast(wasi.filedelta_t, offset), wasi.WHENCE_SET, &new_offset)) {
wasi.ESUCCESS => return,
wasi.EBADF => unreachable, // always a race condition
wasi.EINVAL => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.ENXIO => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const ipos = @bitCast(i64, offset); // the OS treats this as unsigned
switch (errno(system.lseek(fd, ipos, SEEK_SET))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
/// Repositions read/write file offset relative to the current offset.
pub fn lseek_CUR(fd: fd_t, offset: i64) SeekError!void {
if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) {
var result: u64 = undefined;
switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK_CUR))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .windows) {
return windows.SetFilePointerEx_CURRENT(fd, offset);
}
if (builtin.os.tag == .wasi) {
var new_offset: wasi.filesize_t = undefined;
switch (wasi.fd_seek(fd, offset, wasi.WHENCE_CUR, &new_offset)) {
wasi.ESUCCESS => return,
wasi.EBADF => unreachable, // always a race condition
wasi.EINVAL => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.ENXIO => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
switch (errno(system.lseek(fd, offset, SEEK_CUR))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
/// Repositions read/write file offset relative to the end.
pub fn lseek_END(fd: fd_t, offset: i64) SeekError!void {
if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) {
var result: u64 = undefined;
switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK_END))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .windows) {
return windows.SetFilePointerEx_END(fd, offset);
}
if (builtin.os.tag == .wasi) {
var new_offset: wasi.filesize_t = undefined;
switch (wasi.fd_seek(fd, offset, wasi.WHENCE_END, &new_offset)) {
wasi.ESUCCESS => return,
wasi.EBADF => unreachable, // always a race condition
wasi.EINVAL => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.ENXIO => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
switch (errno(system.lseek(fd, offset, SEEK_END))) {
0 => return,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
/// Returns the read/write file offset relative to the beginning.
pub fn lseek_CUR_get(fd: fd_t) SeekError!u64 {
if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) {
var result: u64 = undefined;
switch (errno(system.llseek(fd, 0, &result, SEEK_CUR))) {
0 => return result,
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .windows) {
return windows.SetFilePointerEx_CURRENT_get(fd);
}
if (builtin.os.tag == .wasi) {
var new_offset: wasi.filesize_t = undefined;
switch (wasi.fd_seek(fd, 0, wasi.WHENCE_CUR, &new_offset)) {
wasi.ESUCCESS => return new_offset,
wasi.EBADF => unreachable, // always a race condition
wasi.EINVAL => return error.Unseekable,
wasi.EOVERFLOW => return error.Unseekable,
wasi.ESPIPE => return error.Unseekable,
wasi.ENXIO => return error.Unseekable,
wasi.ENOTCAPABLE => return error.AccessDenied,
else => |err| return unexpectedErrno(err),
}
}
const rc = system.lseek(fd, 0, SEEK_CUR);
switch (errno(rc)) {
0 => return @bitCast(u64, rc),
EBADF => unreachable, // always a race condition
EINVAL => return error.Unseekable,
EOVERFLOW => return error.Unseekable,
ESPIPE => return error.Unseekable,
ENXIO => return error.Unseekable,
else => |err| return unexpectedErrno(err),
}
}
pub const FcntlError = error{
PermissionDenied,
FileBusy,
ProcessFdQuotaExceeded,
Locked,
} || UnexpectedError;
pub fn fcntl(fd: fd_t, cmd: i32, arg: usize) FcntlError!usize {
while (true) {
const rc = system.fcntl(fd, cmd, arg);
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EINTR => continue,
EACCES => return error.Locked,
EBADF => unreachable,
EBUSY => return error.FileBusy,
EINVAL => unreachable, // invalid parameters
EPERM => return error.PermissionDenied,
EMFILE => return error.ProcessFdQuotaExceeded,
ENOTDIR => unreachable, // invalid parameter
else => |err| return unexpectedErrno(err),
}
}
}
fn setSockFlags(sock: socket_t, flags: u32) !void {
if ((flags & SOCK_CLOEXEC) != 0) {
if (builtin.os.tag == .windows) {
// TODO: Find out if this is supported for sockets
} else {
var fd_flags = fcntl(sock, F_GETFD, 0) catch |err| switch (err) {
error.FileBusy => unreachable,
error.Locked => unreachable,
else => |e| return e,
};
fd_flags |= FD_CLOEXEC;
_ = fcntl(sock, F_SETFD, fd_flags) catch |err| switch (err) {
error.FileBusy => unreachable,
error.Locked => unreachable,
else => |e| return e,
};
}
}
if ((flags & SOCK_NONBLOCK) != 0) {
if (builtin.os.tag == .windows) {
var mode: c_ulong = 1;
if (windows.ws2_32.ioctlsocket(sock, windows.ws2_32.FIONBIO, &mode) == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
// TODO: handle more errors
else => |err| return windows.unexpectedWSAError(err),
}
}
} else {
var fl_flags = fcntl(sock, F_GETFL, 0) catch |err| switch (err) {
error.FileBusy => unreachable,
error.Locked => unreachable,
else => |e| return e,
};
fl_flags |= O_NONBLOCK;
_ = fcntl(sock, F_SETFL, fl_flags) catch |err| switch (err) {
error.FileBusy => unreachable,
error.Locked => unreachable,
else => |e| return e,
};
}
}
}
pub const FlockError = error{
WouldBlock,
/// The kernel ran out of memory for allocating file locks
SystemResources,
} || UnexpectedError;
pub fn flock(fd: fd_t, operation: i32) FlockError!void {
while (true) {
const rc = system.flock(fd, operation);
switch (errno(rc)) {
0 => return,
EBADF => unreachable,
EINTR => continue,
EINVAL => unreachable, // invalid parameters
ENOLCK => return error.SystemResources,
EWOULDBLOCK => return error.WouldBlock, // TODO: integrate with async instead of just returning an error
else => |err| return unexpectedErrno(err),
}
}
}
pub const RealPathError = error{
FileNotFound,
AccessDenied,
NameTooLong,
NotSupported,
NotDir,
SymLinkLoop,
InputOutput,
FileTooBig,
IsDir,
ProcessFdQuotaExceeded,
SystemFdQuotaExceeded,
NoDevice,
SystemResources,
NoSpaceLeft,
FileSystem,
BadPathName,
DeviceBusy,
SharingViolation,
PipeBusy,
/// On Windows, file paths must be valid Unicode.
InvalidUtf8,
PathAlreadyExists,
} || UnexpectedError;
/// Return the canonicalized absolute pathname.
/// Expands all symbolic links and resolves references to `.`, `..`, and
/// extra `/` characters in `pathname`.
/// The return value is a slice of `out_buffer`, but not necessarily from the beginning.
/// See also `realpathZ` and `realpathW`.
pub fn realpath(pathname: []const u8, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 {
if (builtin.os.tag == .windows) {
const pathname_w = try windows.sliceToPrefixedFileW(pathname);
return realpathW(pathname_w.span(), out_buffer);
}
if (builtin.os.tag == .wasi) {
@compileError("Use std.fs.wasi.PreopenList to obtain valid Dir handles instead of using absolute paths");
}
const pathname_c = try toPosixPath(pathname);
return realpathZ(&pathname_c, out_buffer);
}
pub const realpathC = @compileError("deprecated: renamed realpathZ");
/// Same as `realpath` except `pathname` is null-terminated.
pub fn realpathZ(pathname: [*:0]const u8, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 {
if (builtin.os.tag == .windows) {
const pathname_w = try windows.cStrToPrefixedFileW(pathname);
return realpathW(pathname_w.span(), out_buffer);
}
if (!builtin.link_libc) {
const flags = if (builtin.os.tag == .linux) O_PATH | O_NONBLOCK | O_CLOEXEC else O_NONBLOCK | O_CLOEXEC;
const fd = openZ(pathname, flags, 0) catch |err| switch (err) {
error.FileLocksNotSupported => unreachable,
else => |e| return e,
};
defer close(fd);
return getFdPath(fd, out_buffer);
}
const result_path = std.c.realpath(pathname, out_buffer) orelse switch (std.c._errno().*) {
EINVAL => unreachable,
EBADF => unreachable,
EFAULT => unreachable,
EACCES => return error.AccessDenied,
ENOENT => return error.FileNotFound,
ENOTSUP => return error.NotSupported,
ENOTDIR => return error.NotDir,
ENAMETOOLONG => return error.NameTooLong,
ELOOP => return error.SymLinkLoop,
EIO => return error.InputOutput,
else => |err| return unexpectedErrno(@intCast(usize, err)),
};
return mem.spanZ(result_path);
}
/// Same as `realpath` except `pathname` is UTF16LE-encoded.
pub fn realpathW(pathname: []const u16, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 {
const w = windows;
const dir = std.fs.cwd().fd;
const access_mask = w.GENERIC_READ | w.SYNCHRONIZE;
const share_access = w.FILE_SHARE_READ;
const creation = w.FILE_OPEN;
const h_file = blk: {
const res = w.OpenFile(pathname, .{
.dir = dir,
.access_mask = access_mask,
.share_access = share_access,
.creation = creation,
.io_mode = .blocking,
}) catch |err| switch (err) {
error.IsDir => break :blk w.OpenFile(pathname, .{
.dir = dir,
.access_mask = access_mask,
.share_access = share_access,
.creation = creation,
.io_mode = .blocking,
.open_dir = true,
}) catch |er| switch (er) {
error.WouldBlock => unreachable,
else => |e2| return e2,
},
error.WouldBlock => unreachable,
else => |e| return e,
};
break :blk res;
};
defer w.CloseHandle(h_file);
return getFdPath(h_file, out_buffer);
}
/// Return canonical path of handle `fd`.
/// This function is very host-specific and is not universally supported by all hosts.
/// For example, while it generally works on Linux, macOS or Windows, it is unsupported
/// on FreeBSD, or WASI.
pub fn getFdPath(fd: fd_t, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 {
switch (builtin.os.tag) {
.windows => {
var wide_buf: [windows.PATH_MAX_WIDE]u16 = undefined;
const wide_slice = try windows.GetFinalPathNameByHandle(fd, .{}, wide_buf[0..]);
// Trust that Windows gives us valid UTF-16LE.
const end_index = std.unicode.utf16leToUtf8(out_buffer, wide_slice) catch unreachable;
return out_buffer[0..end_index];
},
.macos, .ios, .watchos, .tvos => {
// On macOS, we can use F_GETPATH fcntl command to query the OS for
// the path to the file descriptor.
@memset(out_buffer, 0, MAX_PATH_BYTES);
switch (errno(system.fcntl(fd, F_GETPATH, out_buffer))) {
0 => {},
EBADF => return error.FileNotFound,
// TODO man pages for fcntl on macOS don't really tell you what
// errno values to expect when command is F_GETPATH...
else => |err| return unexpectedErrno(err),
}
const len = mem.indexOfScalar(u8, out_buffer[0..], @as(u8, 0)) orelse MAX_PATH_BYTES;
return out_buffer[0..len];
},
.linux => {
var procfs_buf: ["/proc/self/fd/-2147483648".len:0]u8 = undefined;
const proc_path = std.fmt.bufPrint(procfs_buf[0..], "/proc/self/fd/{}\x00", .{fd}) catch unreachable;
const target = readlinkZ(@ptrCast([*:0]const u8, proc_path.ptr), out_buffer) catch |err| {
switch (err) {
error.UnsupportedReparsePointType => unreachable, // Windows only,
else => |e| return e,
}
};
return target;
},
else => @compileError("querying for canonical path of a handle is unsupported on this host"),
}
}
/// Spurious wakeups are possible and no precision of timing is guaranteed.
pub fn nanosleep(seconds: u64, nanoseconds: u64) void {
var req = timespec{
.tv_sec = math.cast(isize, seconds) catch math.maxInt(isize),
.tv_nsec = math.cast(isize, nanoseconds) catch math.maxInt(isize),
};
var rem: timespec = undefined;
while (true) {
switch (errno(system.nanosleep(&req, &rem))) {
EFAULT => unreachable,
EINVAL => {
// Sometimes Darwin returns EINVAL for no reason.
// We treat it as a spurious wakeup.
return;
},
EINTR => {
req = rem;
continue;
},
// This prong handles success as well as unexpected errors.
else => return,
}
}
}
pub fn dl_iterate_phdr(
context: anytype,
comptime Error: type,
comptime callback: fn (info: *dl_phdr_info, size: usize, context: @TypeOf(context)) Error!void,
) Error!void {
const Context = @TypeOf(context);
if (builtin.object_format != .elf)
@compileError("dl_iterate_phdr is not available for this target");
if (builtin.link_libc) {
switch (system.dl_iterate_phdr(struct {
fn callbackC(info: *dl_phdr_info, size: usize, data: ?*c_void) callconv(.C) c_int {
const context_ptr = @ptrCast(*const Context, @alignCast(@alignOf(*const Context), data));
callback(info, size, context_ptr.*) catch |err| return @errorToInt(err);
return 0;
}
}.callbackC, @intToPtr(?*c_void, @ptrToInt(&context)))) {
0 => return,
else => |err| return @errSetCast(Error, @intToError(@intCast(u16, err))), // TODO don't hardcode u16
}
}
const elf_base = std.process.getBaseAddress();
const ehdr = @intToPtr(*elf.Ehdr, elf_base);
// Make sure the base address points to an ELF image
assert(mem.eql(u8, ehdr.e_ident[0..4], "\x7fELF"));
const n_phdr = ehdr.e_phnum;
const phdrs = (@intToPtr([*]elf.Phdr, elf_base + ehdr.e_phoff))[0..n_phdr];
var it = dl.linkmap_iterator(phdrs) catch unreachable;
// The executable has no dynamic link segment, create a single entry for
// the whole ELF image
if (it.end()) {
var info = dl_phdr_info{
.dlpi_addr = 0,
.dlpi_name = "/proc/self/exe",
.dlpi_phdr = phdrs.ptr,
.dlpi_phnum = ehdr.e_phnum,
};
return callback(&info, @sizeOf(dl_phdr_info), context);
}
// Last return value from the callback function
while (it.next()) |entry| {
var dlpi_phdr: [*]elf.Phdr = undefined;
var dlpi_phnum: u16 = undefined;
if (entry.l_addr != 0) {
const elf_header = @intToPtr(*elf.Ehdr, entry.l_addr);
dlpi_phdr = @intToPtr([*]elf.Phdr, entry.l_addr + elf_header.e_phoff);
dlpi_phnum = elf_header.e_phnum;
} else {
// This is the running ELF image
dlpi_phdr = @intToPtr([*]elf.Phdr, elf_base + ehdr.e_phoff);
dlpi_phnum = ehdr.e_phnum;
}
var info = dl_phdr_info{
.dlpi_addr = entry.l_addr,
.dlpi_name = entry.l_name,
.dlpi_phdr = dlpi_phdr,
.dlpi_phnum = dlpi_phnum,
};
try callback(&info, @sizeOf(dl_phdr_info), context);
}
}
pub const ClockGetTimeError = error{UnsupportedClock} || UnexpectedError;
/// TODO: change this to return the timespec as a return value
/// TODO: look into making clk_id an enum
pub fn clock_gettime(clk_id: i32, tp: *timespec) ClockGetTimeError!void {
if (std.Target.current.os.tag == .wasi) {
var ts: timestamp_t = undefined;
switch (system.clock_time_get(@bitCast(u32, clk_id), 1, &ts)) {
0 => {
tp.* = .{
.tv_sec = @intCast(i64, ts / std.time.ns_per_s),
.tv_nsec = @intCast(isize, ts % std.time.ns_per_s),
};
},
EINVAL => return error.UnsupportedClock,
else => |err| return unexpectedErrno(err),
}
return;
}
if (std.Target.current.os.tag == .windows) {
if (clk_id == CLOCK_REALTIME) {
var ft: windows.FILETIME = undefined;
windows.kernel32.GetSystemTimeAsFileTime(&ft);
// FileTime has a granularity of 100 nanoseconds and uses the NTFS/Windows epoch.
const ft64 = (@as(u64, ft.dwHighDateTime) << 32) | ft.dwLowDateTime;
const ft_per_s = std.time.ns_per_s / 100;
tp.* = .{
.tv_sec = @intCast(i64, ft64 / ft_per_s) + std.time.epoch.windows,
.tv_nsec = @intCast(c_long, ft64 % ft_per_s) * 100,
};
return;
} else {
// TODO POSIX implementation of CLOCK_MONOTONIC on Windows.
return error.UnsupportedClock;
}
}
switch (errno(system.clock_gettime(clk_id, tp))) {
0 => return,
EFAULT => unreachable,
EINVAL => return error.UnsupportedClock,
else => |err| return unexpectedErrno(err),
}
}
pub fn clock_getres(clk_id: i32, res: *timespec) ClockGetTimeError!void {
if (std.Target.current.os.tag == .wasi) {
var ts: timestamp_t = undefined;
switch (system.clock_res_get(@bitCast(u32, clk_id), &ts)) {
0 => res.* = .{
.tv_sec = @intCast(i64, ts / std.time.ns_per_s),
.tv_nsec = @intCast(isize, ts % std.time.ns_per_s),
},
EINVAL => return error.UnsupportedClock,
else => |err| return unexpectedErrno(err),
}
return;
}
switch (errno(system.clock_getres(clk_id, res))) {
0 => return,
EFAULT => unreachable,
EINVAL => return error.UnsupportedClock,
else => |err| return unexpectedErrno(err),
}
}
pub const SchedGetAffinityError = error{PermissionDenied} || UnexpectedError;
pub fn sched_getaffinity(pid: pid_t) SchedGetAffinityError!cpu_set_t {
var set: cpu_set_t = undefined;
switch (errno(system.sched_getaffinity(pid, @sizeOf(cpu_set_t), &set))) {
0 => return set,
EFAULT => unreachable,
EINVAL => unreachable,
ESRCH => unreachable,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Used to convert a slice to a null terminated slice on the stack.
/// TODO https://github.com/ziglang/zig/issues/287
pub fn toPosixPath(file_path: []const u8) ![MAX_PATH_BYTES - 1:0]u8 {
if (std.debug.runtime_safety) assert(std.mem.indexOfScalar(u8, file_path, 0) == null);
var path_with_null: [MAX_PATH_BYTES - 1:0]u8 = undefined;
// >= rather than > to make room for the null byte
if (file_path.len >= MAX_PATH_BYTES) return error.NameTooLong;
mem.copy(u8, &path_with_null, file_path);
path_with_null[file_path.len] = 0;
return path_with_null;
}
/// Whether or not error.Unexpected will print its value and a stack trace.
/// if this happens the fix is to add the error code to the corresponding
/// switch expression, possibly introduce a new error in the error set, and
/// send a patch to Zig.
pub const unexpected_error_tracing = builtin.mode == .Debug;
pub const UnexpectedError = error{
/// The Operating System returned an undocumented error code.
/// This error is in theory not possible, but it would be better
/// to handle this error than to invoke undefined behavior.
Unexpected,
};
/// Call this when you made a syscall or something that sets errno
/// and you get an unexpected error.
pub fn unexpectedErrno(err: usize) UnexpectedError {
if (unexpected_error_tracing) {
std.debug.warn("unexpected errno: {}\n", .{err});
std.debug.dumpCurrentStackTrace(null);
}
return error.Unexpected;
}
pub const SigaltstackError = error{
/// The supplied stack size was less than MINSIGSTKSZ.
SizeTooSmall,
/// Attempted to change the signal stack while it was active.
PermissionDenied,
} || UnexpectedError;
pub fn sigaltstack(ss: ?*stack_t, old_ss: ?*stack_t) SigaltstackError!void {
switch (errno(system.sigaltstack(ss, old_ss))) {
0 => return,
EFAULT => unreachable,
EINVAL => unreachable,
ENOMEM => return error.SizeTooSmall,
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
/// Examine and change a signal action.
pub fn sigaction(sig: u6, act: *const Sigaction, oact: ?*Sigaction) void {
switch (errno(system.sigaction(sig, act, oact))) {
0 => return,
EFAULT => unreachable,
EINVAL => unreachable,
else => unreachable,
}
}
pub const FutimensError = error{
/// times is NULL, or both tv_nsec values are UTIME_NOW, and either:
/// * the effective user ID of the caller does not match the owner
/// of the file, the caller does not have write access to the
/// file, and the caller is not privileged (Linux: does not have
/// either the CAP_FOWNER or the CAP_DAC_OVERRIDE capability);
/// or,
/// * the file is marked immutable (see chattr(1)).
AccessDenied,
/// The caller attempted to change one or both timestamps to a value
/// other than the current time, or to change one of the timestamps
/// to the current time while leaving the other timestamp unchanged,
/// (i.e., times is not NULL, neither tv_nsec field is UTIME_NOW,
/// and neither tv_nsec field is UTIME_OMIT) and either:
/// * the caller's effective user ID does not match the owner of
/// file, and the caller is not privileged (Linux: does not have
/// the CAP_FOWNER capability); or,
/// * the file is marked append-only or immutable (see chattr(1)).
PermissionDenied,
ReadOnlyFileSystem,
} || UnexpectedError;
pub fn futimens(fd: fd_t, times: *const [2]timespec) FutimensError!void {
if (builtin.os.tag == .wasi) {
// TODO WASI encodes `wasi.fstflags` to signify magic values
// similar to UTIME_NOW and UTIME_OMIT. Currently, we ignore
// this here, but we should really handle it somehow.
const atim = times[0].toTimestamp();
const mtim = times[1].toTimestamp();
switch (wasi.fd_filestat_set_times(fd, atim, mtim, wasi.FILESTAT_SET_ATIM | wasi.FILESTAT_SET_MTIM)) {
wasi.ESUCCESS => return,
wasi.EACCES => return error.AccessDenied,
wasi.EPERM => return error.PermissionDenied,
wasi.EBADF => unreachable, // always a race condition
wasi.EFAULT => unreachable,
wasi.EINVAL => unreachable,
wasi.EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
switch (errno(system.futimens(fd, times))) {
0 => return,
EACCES => return error.AccessDenied,
EPERM => return error.PermissionDenied,
EBADF => unreachable, // always a race condition
EFAULT => unreachable,
EINVAL => unreachable,
EROFS => return error.ReadOnlyFileSystem,
else => |err| return unexpectedErrno(err),
}
}
pub const GetHostNameError = error{PermissionDenied} || UnexpectedError;
pub fn gethostname(name_buffer: *[HOST_NAME_MAX]u8) GetHostNameError![]u8 {
if (builtin.link_libc) {
switch (errno(system.gethostname(name_buffer, name_buffer.len))) {
0 => return mem.spanZ(@ptrCast([*:0]u8, name_buffer)),
EFAULT => unreachable,
ENAMETOOLONG => unreachable, // HOST_NAME_MAX prevents this
EPERM => return error.PermissionDenied,
else => |err| return unexpectedErrno(err),
}
}
if (builtin.os.tag == .linux) {
const uts = uname();
const hostname = mem.spanZ(@ptrCast([*:0]const u8, &uts.nodename));
mem.copy(u8, name_buffer, hostname);
return name_buffer[0..hostname.len];
}
@compileError("TODO implement gethostname for this OS");
}
pub fn uname() utsname {
var uts: utsname = undefined;
switch (errno(system.uname(&uts))) {
0 => return uts,
EFAULT => unreachable,
else => unreachable,
}
}
pub fn res_mkquery(
op: u4,
dname: []const u8,
class: u8,
ty: u8,
data: []const u8,
newrr: ?[*]const u8,
buf: []u8,
) usize {
// This implementation is ported from musl libc.
// A more idiomatic "ziggy" implementation would be welcome.
var name = dname;
if (mem.endsWith(u8, name, ".")) name.len -= 1;
assert(name.len <= 253);
const n = 17 + name.len + @boolToInt(name.len != 0);
// Construct query template - ID will be filled later
var q: [280]u8 = undefined;
@memset(&q, 0, n);
q[2] = @as(u8, op) * 8 + 1;
q[5] = 1;
mem.copy(u8, q[13..], name);
var i: usize = 13;
var j: usize = undefined;
while (q[i] != 0) : (i = j + 1) {
j = i;
while (q[j] != 0 and q[j] != '.') : (j += 1) {}
// TODO determine the circumstances for this and whether or
// not this should be an error.
if (j - i - 1 > 62) unreachable;
q[i - 1] = @intCast(u8, j - i);
}
q[i + 1] = ty;
q[i + 3] = class;
// Make a reasonably unpredictable id
var ts: timespec = undefined;
clock_gettime(CLOCK_REALTIME, &ts) catch {};
const UInt = std.meta.Int(.unsigned, std.meta.bitCount(@TypeOf(ts.tv_nsec)));
const unsec = @bitCast(UInt, ts.tv_nsec);
const id = @truncate(u32, unsec + unsec / 65536);
q[0] = @truncate(u8, id / 256);
q[1] = @truncate(u8, id);
mem.copy(u8, buf, q[0..n]);
return n;
}
pub const SendError = error{
/// (For UNIX domain sockets, which are identified by pathname) Write permission is denied
/// on the destination socket file, or search permission is denied for one of the
/// directories the path prefix. (See path_resolution(7).)
/// (For UDP sockets) An attempt was made to send to a network/broadcast address as though
/// it was a unicast address.
AccessDenied,
/// The socket is marked nonblocking and the requested operation would block, and
/// there is no global event loop configured.
/// It's also possible to get this error under the following condition:
/// (Internet domain datagram sockets) The socket referred to by sockfd had not previously
/// been bound to an address and, upon attempting to bind it to an ephemeral port, it was
/// determined that all port numbers in the ephemeral port range are currently in use. See
/// the discussion of /proc/sys/net/ipv4/ip_local_port_range in ip(7).
WouldBlock,
/// Another Fast Open is already in progress.
FastOpenAlreadyInProgress,
/// Connection reset by peer.
ConnectionResetByPeer,
/// The socket type requires that message be sent atomically, and the size of the message
/// to be sent made this impossible. The message is not transmitted.
MessageTooBig,
/// The output queue for a network interface was full. This generally indicates that the
/// interface has stopped sending, but may be caused by transient congestion. (Normally,
/// this does not occur in Linux. Packets are just silently dropped when a device queue
/// overflows.)
/// This is also caused when there is not enough kernel memory available.
SystemResources,
/// The local end has been shut down on a connection oriented socket. In this case, the
/// process will also receive a SIGPIPE unless MSG_NOSIGNAL is set.
BrokenPipe,
FileDescriptorNotASocket,
} || UnexpectedError;
/// Transmit a message to another socket.
///
/// The `sendto` call may be used only when the socket is in a connected state (so that the intended
/// recipient is known). The following call
///
/// send(sockfd, buf, len, flags);
///
/// is equivalent to
///
/// sendto(sockfd, buf, len, flags, NULL, 0);
///
/// If sendto() is used on a connection-mode (`SOCK_STREAM`, `SOCK_SEQPACKET`) socket, the arguments
/// `dest_addr` and `addrlen` are asserted to be `null` and `0` respectively, and asserted
/// that the socket was actually connected.
/// Otherwise, the address of the target is given by `dest_addr` with `addrlen` specifying its size.
///
/// If the message is too long to pass atomically through the underlying protocol,
/// `SendError.MessageTooBig` is returned, and the message is not transmitted.
///
/// There is no indication of failure to deliver.
///
/// When the message does not fit into the send buffer of the socket, `sendto` normally blocks,
/// unless the socket has been placed in nonblocking I/O mode. In nonblocking mode it would fail
/// with `SendError.WouldBlock`. The `select` call may be used to determine when it is
/// possible to send more data.
pub fn sendto(
/// The file descriptor of the sending socket.
sockfd: socket_t,
/// Message to send.
buf: []const u8,
flags: u32,
dest_addr: ?*const sockaddr,
addrlen: socklen_t,
) SendError!usize {
while (true) {
const rc = system.sendto(sockfd, buf.ptr, buf.len, flags, dest_addr, addrlen);
if (builtin.os.tag == .windows) {
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSAEACCES => return error.AccessDenied,
.WSAECONNRESET => return error.ConnectionResetByPeer,
.WSAEMSGSIZE => return error.MessageTooBig,
.WSAENOBUFS => return error.SystemResources,
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
// TODO: handle more errors
else => |err| return windows.unexpectedWSAError(err),
}
} else {
return @intCast(usize, rc);
}
} else {
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EACCES => return error.AccessDenied,
EAGAIN => return error.WouldBlock,
EALREADY => return error.FastOpenAlreadyInProgress,
EBADF => unreachable, // always a race condition
ECONNRESET => return error.ConnectionResetByPeer,
EDESTADDRREQ => unreachable, // The socket is not connection-mode, and no peer address is set.
EFAULT => unreachable, // An invalid user space address was specified for an argument.
EINTR => continue,
EINVAL => unreachable, // Invalid argument passed.
EISCONN => unreachable, // connection-mode socket was connected already but a recipient was specified
EMSGSIZE => return error.MessageTooBig,
ENOBUFS => return error.SystemResources,
ENOMEM => return error.SystemResources,
ENOTCONN => unreachable, // The socket is not connected, and no target has been given.
ENOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket.
EOPNOTSUPP => unreachable, // Some bit in the flags argument is inappropriate for the socket type.
EPIPE => return error.BrokenPipe,
else => |err| return unexpectedErrno(err),
}
}
}
}
/// Transmit a message to another socket.
///
/// The `send` call may be used only when the socket is in a connected state (so that the intended
/// recipient is known). The only difference between `send` and `write` is the presence of
/// flags. With a zero flags argument, `send` is equivalent to `write`. Also, the following
/// call
///
/// send(sockfd, buf, len, flags);
///
/// is equivalent to
///
/// sendto(sockfd, buf, len, flags, NULL, 0);
///
/// There is no indication of failure to deliver.
///
/// When the message does not fit into the send buffer of the socket, `send` normally blocks,
/// unless the socket has been placed in nonblocking I/O mode. In nonblocking mode it would fail
/// with `SendError.WouldBlock`. The `select` call may be used to determine when it is
/// possible to send more data.
pub fn send(
/// The file descriptor of the sending socket.
sockfd: socket_t,
buf: []const u8,
flags: u32,
) SendError!usize {
return sendto(sockfd, buf, flags, null, 0);
}
pub const SendFileError = PReadError || WriteError || SendError;
fn count_iovec_bytes(iovs: []const iovec_const) usize {
var count: usize = 0;
for (iovs) |iov| {
count += iov.iov_len;
}
return count;
}
/// Transfer data between file descriptors, with optional headers and trailers.
/// Returns the number of bytes written, which can be zero.
///
/// The `sendfile` call copies `in_len` bytes from one file descriptor to another. When possible,
/// this is done within the operating system kernel, which can provide better performance
/// characteristics than transferring data from kernel to user space and back, such as with
/// `read` and `write` calls. When `in_len` is `0`, it means to copy until the end of the input file has been
/// reached. Note, however, that partial writes are still possible in this case.
///
/// `in_fd` must be a file descriptor opened for reading, and `out_fd` must be a file descriptor
/// opened for writing. They may be any kind of file descriptor; however, if `in_fd` is not a regular
/// file system file, it may cause this function to fall back to calling `read` and `write`, in which case
/// atomicity guarantees no longer apply.
///
/// Copying begins reading at `in_offset`. The input file descriptor seek position is ignored and not updated.
/// If the output file descriptor has a seek position, it is updated as bytes are written. When
/// `in_offset` is past the end of the input file, it successfully reads 0 bytes.
///
/// `flags` has different meanings per operating system; refer to the respective man pages.
///
/// These systems support atomically sending everything, including headers and trailers:
/// * macOS
/// * FreeBSD
///
/// These systems support in-kernel data copying, but headers and trailers are not sent atomically:
/// * Linux
///
/// Other systems fall back to calling `read` / `write`.
///
/// Linux has a limit on how many bytes may be transferred in one `sendfile` call, which is `0x7ffff000`
/// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as
/// well as stuffing the errno codes into the last `4096` values. This is cited on the `sendfile` man page.
/// The limit on Darwin is `0x7fffffff`, trying to write more than that returns EINVAL.
/// The corresponding POSIX limit on this is `math.maxInt(isize)`.
pub fn sendfile(
out_fd: fd_t,
in_fd: fd_t,
in_offset: u64,
in_len: u64,
headers: []const iovec_const,
trailers: []const iovec_const,
flags: u32,
) SendFileError!usize {
var header_done = false;
var total_written: usize = 0;
// Prevents EOVERFLOW.
const size_t = @Type(std.builtin.TypeInfo{
.Int = .{
.is_signed = false,
.bits = @typeInfo(usize).Int.bits - 1,
},
});
const max_count = switch (std.Target.current.os.tag) {
.linux => 0x7ffff000,
.macos, .ios, .watchos, .tvos => math.maxInt(i32),
else => math.maxInt(size_t),
};
switch (std.Target.current.os.tag) {
.linux => sf: {
// sendfile() first appeared in Linux 2.2, glibc 2.1.
const call_sf = comptime if (builtin.link_libc)
std.c.versionCheck(.{ .major = 2, .minor = 1 }).ok
else
std.Target.current.os.version_range.linux.range.max.order(.{ .major = 2, .minor = 2 }) != .lt;
if (!call_sf) break :sf;
if (headers.len != 0) {
const amt = try writev(out_fd, headers);
total_written += amt;
if (amt < count_iovec_bytes(headers)) return total_written;
header_done = true;
}
// Here we match BSD behavior, making a zero count value send as many bytes as possible.
const adjusted_count = if (in_len == 0) max_count else math.min(in_len, @as(size_t, max_count));
while (true) {
var offset: off_t = @bitCast(off_t, in_offset);
const rc = system.sendfile(out_fd, in_fd, &offset, adjusted_count);
switch (errno(rc)) {
0 => {
const amt = @bitCast(usize, rc);
total_written += amt;
if (in_len == 0 and amt == 0) {
// We have detected EOF from `in_fd`.
break;
} else if (amt < in_len) {
return total_written;
} else {
break;
}
},
EBADF => unreachable, // Always a race condition.
EFAULT => unreachable, // Segmentation fault.
EOVERFLOW => unreachable, // We avoid passing too large of a `count`.
ENOTCONN => unreachable, // `out_fd` is an unconnected socket.
EINVAL, ENOSYS => {
// EINVAL could be any of the following situations:
// * Descriptor is not valid or locked
// * an mmap(2)-like operation is not available for in_fd
// * count is negative
// * out_fd has the O_APPEND flag set
// Because of the "mmap(2)-like operation" possibility, we fall back to doing read/write
// manually, the same as ENOSYS.
break :sf;
},
EAGAIN => if (std.event.Loop.instance) |loop| {
loop.waitUntilFdWritable(out_fd);
continue;
} else {
return error.WouldBlock;
},
EIO => return error.InputOutput,
EPIPE => return error.BrokenPipe,
ENOMEM => return error.SystemResources,
ENXIO => return error.Unseekable,
ESPIPE => return error.Unseekable,
else => |err| {
const discard = unexpectedErrno(err);
break :sf;
},
}
}
if (trailers.len != 0) {
total_written += try writev(out_fd, trailers);
}
return total_written;
},
.freebsd => sf: {
var hdtr_data: std.c.sf_hdtr = undefined;
var hdtr: ?*std.c.sf_hdtr = null;
if (headers.len != 0 or trailers.len != 0) {
// Here we carefully avoid `@intCast` by returning partial writes when
// too many io vectors are provided.
const hdr_cnt = math.cast(u31, headers.len) catch math.maxInt(u31);
if (headers.len > hdr_cnt) return writev(out_fd, headers);
const trl_cnt = math.cast(u31, trailers.len) catch math.maxInt(u31);
hdtr_data = std.c.sf_hdtr{
.headers = headers.ptr,
.hdr_cnt = hdr_cnt,
.trailers = trailers.ptr,
.trl_cnt = trl_cnt,
};
hdtr = &hdtr_data;
}
const adjusted_count = math.min(in_len, max_count);
while (true) {
var sbytes: off_t = undefined;
const offset = @bitCast(off_t, in_offset);
const err = errno(system.sendfile(in_fd, out_fd, offset, adjusted_count, hdtr, &sbytes, flags));
const amt = @bitCast(usize, sbytes);
switch (err) {
0 => return amt,
EBADF => unreachable, // Always a race condition.
EFAULT => unreachable, // Segmentation fault.
ENOTCONN => unreachable, // `out_fd` is an unconnected socket.
EINVAL, EOPNOTSUPP, ENOTSOCK, ENOSYS => {
// EINVAL could be any of the following situations:
// * The fd argument is not a regular file.
// * The s argument is not a SOCK_STREAM type socket.
// * The offset argument is negative.
// Because of some of these possibilities, we fall back to doing read/write
// manually, the same as ENOSYS.
break :sf;
},
EINTR => if (amt != 0) return amt else continue,
EAGAIN => if (amt != 0) {
return amt;
} else if (std.event.Loop.instance) |loop| {
loop.waitUntilFdWritable(out_fd);
continue;
} else {
return error.WouldBlock;
},
EBUSY => if (amt != 0) {
return amt;
} else if (std.event.Loop.instance) |loop| {
loop.waitUntilFdReadable(in_fd);
continue;
} else {
return error.WouldBlock;
},
EIO => return error.InputOutput,
ENOBUFS => return error.SystemResources,
EPIPE => return error.BrokenPipe,
else => {
const discard = unexpectedErrno(err);
if (amt != 0) {
return amt;
} else {
break :sf;
}
},
}
}
},
.macos, .ios, .tvos, .watchos => sf: {
var hdtr_data: std.c.sf_hdtr = undefined;
var hdtr: ?*std.c.sf_hdtr = null;
if (headers.len != 0 or trailers.len != 0) {
// Here we carefully avoid `@intCast` by returning partial writes when
// too many io vectors are provided.
const hdr_cnt = math.cast(u31, headers.len) catch math.maxInt(u31);
if (headers.len > hdr_cnt) return writev(out_fd, headers);
const trl_cnt = math.cast(u31, trailers.len) catch math.maxInt(u31);
hdtr_data = std.c.sf_hdtr{
.headers = headers.ptr,
.hdr_cnt = hdr_cnt,
.trailers = trailers.ptr,
.trl_cnt = trl_cnt,
};
hdtr = &hdtr_data;
}
const adjusted_count = math.min(in_len, @as(u63, max_count));
while (true) {
var sbytes: off_t = adjusted_count;
const signed_offset = @bitCast(i64, in_offset);
const err = errno(system.sendfile(in_fd, out_fd, signed_offset, &sbytes, hdtr, flags));
const amt = @bitCast(usize, sbytes);
switch (err) {
0 => return amt,
EBADF => unreachable, // Always a race condition.
EFAULT => unreachable, // Segmentation fault.
EINVAL => unreachable,
ENOTCONN => unreachable, // `out_fd` is an unconnected socket.
ENOTSUP, ENOTSOCK, ENOSYS => break :sf,
EINTR => if (amt != 0) return amt else continue,
EAGAIN => if (amt != 0) {
return amt;
} else if (std.event.Loop.instance) |loop| {
loop.waitUntilFdWritable(out_fd);
continue;
} else {
return error.WouldBlock;
},
EIO => return error.InputOutput,
EPIPE => return error.BrokenPipe,
else => {
const discard = unexpectedErrno(err);
if (amt != 0) {
return amt;
} else {
break :sf;
}
},
}
}
},
else => {}, // fall back to read/write
}
if (headers.len != 0 and !header_done) {
const amt = try writev(out_fd, headers);
total_written += amt;
if (amt < count_iovec_bytes(headers)) return total_written;
}
rw: {
var buf: [8 * 4096]u8 = undefined;
// Here we match BSD behavior, making a zero count value send as many bytes as possible.
const adjusted_count = if (in_len == 0) buf.len else math.min(buf.len, in_len);
const amt_read = try pread(in_fd, buf[0..adjusted_count], in_offset);
if (amt_read == 0) {
if (in_len == 0) {
// We have detected EOF from `in_fd`.
break :rw;
} else {
return total_written;
}
}
const amt_written = try write(out_fd, buf[0..amt_read]);
total_written += amt_written;
if (amt_written < in_len or in_len == 0) return total_written;
}
if (trailers.len != 0) {
total_written += try writev(out_fd, trailers);
}
return total_written;
}
pub const CopyFileRangeError = error{
FileTooBig,
InputOutput,
/// `fd_in` is not open for reading; or `fd_out` is not open for writing;
/// or the `O_APPEND` flag is set for `fd_out`.
FilesOpenedWithWrongFlags,
IsDir,
OutOfMemory,
NoSpaceLeft,
Unseekable,
PermissionDenied,
FileBusy,
} || PReadError || PWriteError || UnexpectedError;
var has_copy_file_range_syscall = init: {
const kernel_has_syscall = std.Target.current.os.isAtLeast(.linux, .{ .major = 4, .minor = 5 }) orelse true;
break :init std.atomic.Int(bool).init(kernel_has_syscall);
};
/// Transfer data between file descriptors at specified offsets.
/// Returns the number of bytes written, which can less than requested.
///
/// The `copy_file_range` call copies `len` bytes from one file descriptor to another. When possible,
/// this is done within the operating system kernel, which can provide better performance
/// characteristics than transferring data from kernel to user space and back, such as with
/// `pread` and `pwrite` calls.
///
/// `fd_in` must be a file descriptor opened for reading, and `fd_out` must be a file descriptor
/// opened for writing. They may be any kind of file descriptor; however, if `fd_in` is not a regular
/// file system file, it may cause this function to fall back to calling `pread` and `pwrite`, in which case
/// atomicity guarantees no longer apply.
///
/// If `fd_in` and `fd_out` are the same, source and target ranges must not overlap.
/// The file descriptor seek positions are ignored and not updated.
/// When `off_in` is past the end of the input file, it successfully reads 0 bytes.
///
/// `flags` has different meanings per operating system; refer to the respective man pages.
///
/// These systems support in-kernel data copying:
/// * Linux 4.5 (cross-filesystem 5.3)
///
/// Other systems fall back to calling `pread` / `pwrite`.
///
/// Maximum offsets on Linux are `math.maxInt(i64)`.
pub fn copy_file_range(fd_in: fd_t, off_in: u64, fd_out: fd_t, off_out: u64, len: usize, flags: u32) CopyFileRangeError!usize {
const use_c = std.c.versionCheck(.{ .major = 2, .minor = 27, .patch = 0 }).ok;
if (std.Target.current.os.tag == .linux and
(use_c or has_copy_file_range_syscall.get()))
{
const sys = if (use_c) std.c else linux;
var off_in_copy = @bitCast(i64, off_in);
var off_out_copy = @bitCast(i64, off_out);
const rc = sys.copy_file_range(fd_in, &off_in_copy, fd_out, &off_out_copy, len, flags);
switch (sys.getErrno(rc)) {
0 => return @intCast(usize, rc),
EBADF => return error.FilesOpenedWithWrongFlags,
EFBIG => return error.FileTooBig,
EIO => return error.InputOutput,
EISDIR => return error.IsDir,
ENOMEM => return error.OutOfMemory,
ENOSPC => return error.NoSpaceLeft,
EOVERFLOW => return error.Unseekable,
EPERM => return error.PermissionDenied,
ETXTBSY => return error.FileBusy,
// these may not be regular files, try fallback
EINVAL => {},
// support for cross-filesystem copy added in Linux 5.3, use fallback
EXDEV => {},
// syscall added in Linux 4.5, use fallback
ENOSYS => {
has_copy_file_range_syscall.set(false);
},
else => |err| return unexpectedErrno(err),
}
}
var buf: [8 * 4096]u8 = undefined;
const adjusted_count = math.min(buf.len, len);
const amt_read = try pread(fd_in, buf[0..adjusted_count], off_in);
// TODO without @as the line below fails to compile for wasm32-wasi:
// error: integer value 0 cannot be coerced to type 'os.PWriteError!usize'
if (amt_read == 0) return @as(usize, 0);
return pwrite(fd_out, buf[0..amt_read], off_out);
}
pub const PollError = error{
/// The network subsystem has failed.
NetworkSubsystemFailed,
/// The kernel had no space to allocate file descriptor tables.
SystemResources,
} || UnexpectedError;
pub fn poll(fds: []pollfd, timeout: i32) PollError!usize {
while (true) {
const rc = system.poll(fds.ptr, fds.len, timeout);
if (builtin.os.tag == .windows) {
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAENOBUFS => return error.SystemResources,
// TODO: handle more errors
else => |err| return windows.unexpectedWSAError(err),
}
} else {
return @intCast(usize, rc);
}
} else {
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EFAULT => unreachable,
EINTR => continue,
EINVAL => unreachable,
ENOMEM => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
unreachable;
}
}
pub const RecvFromError = error{
/// The socket is marked nonblocking and the requested operation would block, and
/// there is no global event loop configured.
WouldBlock,
/// A remote host refused to allow the network connection, typically because it is not
/// running the requested service.
ConnectionRefused,
/// Could not allocate kernel memory.
SystemResources,
ConnectionResetByPeer,
/// The socket has not been bound.
SocketNotBound,
/// The UDP message was too big for the buffer and part of it has been discarded
MessageTooBig,
/// The network subsystem has failed.
NetworkSubsystemFailed,
/// The socket is not connected (connection-oriented sockets only).
SocketNotConnected,
} || UnexpectedError;
pub fn recv(sock: socket_t, buf: []u8, flags: u32) RecvFromError!usize {
return recvfrom(sock, buf, flags, null, null);
}
/// If `sockfd` is opened in non blocking mode, the function will
/// return error.WouldBlock when EAGAIN is received.
pub fn recvfrom(
sockfd: socket_t,
buf: []u8,
flags: u32,
src_addr: ?*sockaddr,
addrlen: ?*socklen_t,
) RecvFromError!usize {
while (true) {
const rc = system.recvfrom(sockfd, buf.ptr, buf.len, flags, src_addr, addrlen);
if (builtin.os.tag == .windows) {
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable,
.WSAECONNRESET => return error.ConnectionResetByPeer,
.WSAEINVAL => return error.SocketNotBound,
.WSAEMSGSIZE => return error.MessageTooBig,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAENOTCONN => return error.SocketNotConnected,
.WSAEWOULDBLOCK => return error.WouldBlock,
// TODO: handle more errors
else => |err| return windows.unexpectedWSAError(err),
}
} else {
return @intCast(usize, rc);
}
} else {
switch (errno(rc)) {
0 => return @intCast(usize, rc),
EBADF => unreachable, // always a race condition
EFAULT => unreachable,
EINVAL => unreachable,
ENOTCONN => unreachable,
ENOTSOCK => unreachable,
EINTR => continue,
EAGAIN => return error.WouldBlock,
ENOMEM => return error.SystemResources,
ECONNREFUSED => return error.ConnectionRefused,
else => |err| return unexpectedErrno(err),
}
}
}
}
pub const DnExpandError = error{InvalidDnsPacket};
pub fn dn_expand(
msg: []const u8,
comp_dn: []const u8,
exp_dn: []u8,
) DnExpandError!usize {
// This implementation is ported from musl libc.
// A more idiomatic "ziggy" implementation would be welcome.
var p = comp_dn.ptr;
var len: usize = std.math.maxInt(usize);
const end = msg.ptr + msg.len;
if (p == end or exp_dn.len == 0) return error.InvalidDnsPacket;
var dest = exp_dn.ptr;
const dend = dest + std.math.min(exp_dn.len, 254);
// detect reference loop using an iteration counter
var i: usize = 0;
while (i < msg.len) : (i += 2) {
// loop invariants: p<end, dest<dend
if ((p[0] & 0xc0) != 0) {
if (p + 1 == end) return error.InvalidDnsPacket;
var j = ((p[0] & @as(usize, 0x3f)) << 8) | p[1];
if (len == std.math.maxInt(usize)) len = @ptrToInt(p) + 2 - @ptrToInt(comp_dn.ptr);
if (j >= msg.len) return error.InvalidDnsPacket;
p = msg.ptr + j;
} else if (p[0] != 0) {
if (dest != exp_dn.ptr) {
dest.* = '.';
dest += 1;
}
var j = p[0];
p += 1;
if (j >= @ptrToInt(end) - @ptrToInt(p) or j >= @ptrToInt(dend) - @ptrToInt(dest)) {
return error.InvalidDnsPacket;
}
while (j != 0) {
j -= 1;
dest.* = p[0];
dest += 1;
p += 1;
}
} else {
dest.* = 0;
if (len == std.math.maxInt(usize)) len = @ptrToInt(p) + 1 - @ptrToInt(comp_dn.ptr);
return len;
}
}
return error.InvalidDnsPacket;
}
pub const SchedYieldError = error{
/// The system is not configured to allow yielding
SystemCannotYield,
};
pub fn sched_yield() SchedYieldError!void {
if (builtin.os.tag == .windows) {
// The return value has to do with how many other threads there are; it is not
// an error condition on Windows.
_ = windows.kernel32.SwitchToThread();
return;
}
switch (errno(system.sched_yield())) {
0 => return,
ENOSYS => return error.SystemCannotYield,
else => return error.SystemCannotYield,
}
}
pub const SetSockOptError = error{
/// The socket is already connected, and a specified option cannot be set while the socket is connected.
AlreadyConnected,
/// The option is not supported by the protocol.
InvalidProtocolOption,
/// The send and receive timeout values are too big to fit into the timeout fields in the socket structure.
TimeoutTooBig,
/// Insufficient resources are available in the system to complete the call.
SystemResources,
NetworkSubsystemFailed,
FileDescriptorNotASocket,
SocketNotBound,
} || UnexpectedError;
/// Set a socket's options.
pub fn setsockopt(fd: socket_t, level: u32, optname: u32, opt: []const u8) SetSockOptError!void {
if (builtin.os.tag == .windows) {
const rc = windows.ws2_32.setsockopt(fd, level, optname, opt.ptr, @intCast(socklen_t, opt.len));
if (rc == windows.ws2_32.SOCKET_ERROR) {
switch (windows.ws2_32.WSAGetLastError()) {
.WSANOTINITIALISED => unreachable,
.WSAENETDOWN => return error.NetworkSubsystemFailed,
.WSAEFAULT => unreachable,
.WSAENOTSOCK => return error.FileDescriptorNotASocket,
.WSAEINVAL => return error.SocketNotBound,
else => |err| return windows.unexpectedWSAError(err),
}
}
return;
} else {
switch (errno(system.setsockopt(fd, level, optname, opt.ptr, @intCast(socklen_t, opt.len)))) {
0 => {},
EBADF => unreachable, // always a race condition
ENOTSOCK => unreachable, // always a race condition
EINVAL => unreachable,
EFAULT => unreachable,
EDOM => return error.TimeoutTooBig,
EISCONN => return error.AlreadyConnected,
ENOPROTOOPT => return error.InvalidProtocolOption,
ENOMEM => return error.SystemResources,
ENOBUFS => return error.SystemResources,
else => |err| return unexpectedErrno(err),
}
}
}
pub const MemFdCreateError = error{
SystemFdQuotaExceeded,
ProcessFdQuotaExceeded,
OutOfMemory,
/// memfd_create is available in Linux 3.17 and later. This error is returned
/// for older kernel versions.
SystemOutdated,
} || UnexpectedError;
pub const memfd_createC = @compileError("deprecated: renamed to memfd_createZ");
pub fn memfd_createZ(name: [*:0]const u8, flags: u32) MemFdCreateError!fd_t {
// memfd_create is available only in glibc versions starting with 2.27.
const use_c = std.c.versionCheck(.{ .major = 2, .minor = 27, .patch = 0 }).ok;
const sys = if (use_c) std.c else linux;
const getErrno = if (use_c) std.c.getErrno else linux.getErrno;
const rc = sys.memfd_create(name, flags);
switch (getErrno(rc)) {
0 => return @intCast(fd_t, rc),
EFAULT => unreachable, // name has invalid memory
EINVAL => unreachable, // name/flags are faulty
ENFILE => return error.SystemFdQuotaExceeded,
EMFILE => return error.ProcessFdQuotaExceeded,
ENOMEM => return error.OutOfMemory,
ENOSYS => return error.SystemOutdated,
else => |err| return unexpectedErrno(err),
}
}
pub const MFD_NAME_PREFIX = "memfd:";
pub const MFD_MAX_NAME_LEN = NAME_MAX - MFD_NAME_PREFIX.len;
fn toMemFdPath(name: []const u8) ![MFD_MAX_NAME_LEN:0]u8 {
var path_with_null: [MFD_MAX_NAME_LEN:0]u8 = undefined;
// >= rather than > to make room for the null byte
if (name.len >= MFD_MAX_NAME_LEN) return error.NameTooLong;
mem.copy(u8, &path_with_null, name);
path_with_null[name.len] = 0;
return path_with_null;
}
pub fn memfd_create(name: []const u8, flags: u32) !fd_t {
const name_t = try toMemFdPath(name);
return memfd_createZ(&name_t, flags);
}
pub fn getrusage(who: i32) rusage {
var result: rusage = undefined;
const rc = system.getrusage(who, &result);
switch (errno(rc)) {
0 => return result,
EINVAL => unreachable,
EFAULT => unreachable,
else => unreachable,
}
}
pub const TermiosGetError = error{NotATerminal} || UnexpectedError;
pub fn tcgetattr(handle: fd_t) TermiosGetError!termios {
while (true) {
var term: termios = undefined;
switch (errno(system.tcgetattr(handle, &term))) {
0 => return term,
EINTR => continue,
EBADF => unreachable,
ENOTTY => return error.NotATerminal,
else => |err| return unexpectedErrno(err),
}
}
}
pub const TermiosSetError = TermiosGetError || error{ProcessOrphaned};
pub fn tcsetattr(handle: fd_t, optional_action: TCSA, termios_p: termios) TermiosSetError!void {
while (true) {
switch (errno(system.tcsetattr(handle, optional_action, &termios_p))) {
0 => return,
EBADF => unreachable,
EINTR => continue,
EINVAL => unreachable,
ENOTTY => return error.NotATerminal,
EIO => return error.ProcessOrphaned,
else => |err| return unexpectedErrno(err),
}
}
}
const IoCtl_SIOCGIFINDEX_Error = error{
FileSystem,
InterfaceNotFound,
} || UnexpectedError;
pub fn ioctl_SIOCGIFINDEX(fd: fd_t, ifr: *ifreq) IoCtl_SIOCGIFINDEX_Error!void {
while (true) {
switch (errno(system.ioctl(fd, SIOCGIFINDEX, @ptrToInt(ifr)))) {
0 => return,
EINVAL => unreachable, // Bad parameters.
ENOTTY => unreachable,
ENXIO => unreachable,
EBADF => unreachable, // Always a race condition.
EFAULT => unreachable, // Bad pointer parameter.
EINTR => continue,
EIO => return error.FileSystem,
ENODEV => return error.InterfaceNotFound,
else => |err| return unexpectedErrno(err),
}
}
}
pub fn signalfd(fd: fd_t, mask: *const sigset_t, flags: u32) !fd_t {
const rc = system.signalfd(fd, mask, flags);
switch (errno(rc)) {
0 => return @intCast(fd_t, rc),
EBADF, EINVAL => unreachable,
ENFILE => return error.SystemFdQuotaExceeded,
ENOMEM => return error.SystemResources,
EMFILE => return error.ProcessResources,
ENODEV => return error.InodeMountFail,
ENOSYS => return error.SystemOutdated,
else => |err| return std.os.unexpectedErrno(err),
}
}
pub const SyncError = error{
InputOutput,
NoSpaceLeft,
DiskQuota,
AccessDenied,
} || UnexpectedError;
/// Write all pending file contents and metadata modifications to all filesystems.
pub fn sync() void {
system.sync();
}
/// Write all pending file contents and metadata modifications to the filesystem which contains the specified file.
pub fn syncfs(fd: fd_t) SyncError!void {
const rc = system.syncfs(fd);
switch (errno(rc)) {
0 => return,
EBADF, EINVAL, EROFS => unreachable,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EDQUOT => return error.DiskQuota,
else => |err| return std.os.unexpectedErrno(err),
}
}
/// Write all pending file contents and metadata modifications for the specified file descriptor to the underlying filesystem.
pub fn fsync(fd: fd_t) SyncError!void {
if (std.Target.current.os.tag == .windows) {
if (windows.kernel32.FlushFileBuffers(fd) != 0)
return;
switch (windows.kernel32.GetLastError()) {
.SUCCESS => return,
.INVALID_HANDLE => unreachable,
.ACCESS_DENIED => return error.AccessDenied, // a sync was performed but the system couldn't update the access time
.UNEXP_NET_ERR => return error.InputOutput,
else => return error.InputOutput,
}
}
const rc = system.fsync(fd);
switch (errno(rc)) {
0 => return,
EBADF, EINVAL, EROFS => unreachable,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EDQUOT => return error.DiskQuota,
else => |err| return std.os.unexpectedErrno(err),
}
}
/// Write all pending file contents for the specified file descriptor to the underlying filesystem, but not necessarily the metadata.
pub fn fdatasync(fd: fd_t) SyncError!void {
if (std.Target.current.os.tag == .windows) {
return fsync(fd) catch |err| switch (err) {
SyncError.AccessDenied => return, // fdatasync doesn't promise that the access time was synced
else => return err,
};
}
const rc = system.fdatasync(fd);
switch (errno(rc)) {
0 => return,
EBADF, EINVAL, EROFS => unreachable,
EIO => return error.InputOutput,
ENOSPC => return error.NoSpaceLeft,
EDQUOT => return error.DiskQuota,
else => |err| return std.os.unexpectedErrno(err),
}
}
pub const PrctlError = error{
/// Can only occur with PR_SET_SECCOMP/SECCOMP_MODE_FILTER or
/// PR_SET_MM/PR_SET_MM_EXE_FILE
AccessDenied,
/// Can only occur with PR_SET_MM/PR_SET_MM_EXE_FILE
InvalidFileDescriptor,
InvalidAddress,
/// Can only occur with PR_SET_SPECULATION_CTRL, PR_MPX_ENABLE_MANAGEMENT,
/// or PR_MPX_DISABLE_MANAGEMENT
UnsupportedFeature,
/// Can only occur wih PR_SET_FP_MODE
OperationNotSupported,
PermissionDenied,
} || UnexpectedError;
pub fn prctl(option: PR, args: anytype) PrctlError!u31 {
if (@typeInfo(@TypeOf(args)) != .Struct)
@compileError("Expected tuple or struct argument, found " ++ @typeName(@TypeOf(args)));
if (args.len > 4)
@compileError("prctl takes a maximum of 4 optional arguments");
var buf: [4]usize = undefined;
{
comptime var i = 0;
inline while (i < args.len) : (i += 1) buf[i] = args[i];
}
const rc = system.prctl(@enumToInt(option), buf[0], buf[1], buf[2], buf[3]);
switch (errno(rc)) {
0 => return @intCast(u31, rc),
EACCES => return error.AccessDenied,
EBADF => return error.InvalidFileDescriptor,
EFAULT => return error.InvalidAddress,
EINVAL => unreachable,
ENODEV, ENXIO => return error.UnsupportedFeature,
EOPNOTSUPP => return error.OperationNotSupported,
EPERM, EBUSY => return error.PermissionDenied,
ERANGE => unreachable,
else => |err| return std.os.unexpectedErrno(err),
}
}
pub const GetrlimitError = UnexpectedError;
pub fn getrlimit(resource: rlimit_resource) GetrlimitError!rlimit {
var limits: rlimit = undefined;
const rc = system.getrlimit(resource, &limits);
switch (errno(rc)) {
0 => return limits,
EFAULT => unreachable, // bogus pointer
EINVAL => unreachable,
else => |err| return std.os.unexpectedErrno(err),
}
}
pub const SetrlimitError = error{PermissionDenied} || UnexpectedError;
pub fn setrlimit(resource: rlimit_resource, limits: rlimit) SetrlimitError!void {
const rc = system.setrlimit(resource, &limits);
switch (errno(rc)) {
0 => return,
EFAULT => unreachable, // bogus pointer
EINVAL => unreachable,
EPERM => return error.PermissionDenied,
else => |err| return std.os.unexpectedErrno(err),
}
}
Reference in New Issue View Git Blame Copy Permalink