zig/lib/std/fs/get_app_data_dir.zig
Ian Johnson 0a70455095 Fix handling of empty XDG environment variables
Closes #21132

According to the XDG Base Directory specification
(https://specifications.freedesktop.org/basedir-spec/latest/#variables),
empty values for these environment variables should be treated the same
as if they are unset. Specifically, for the instances changed in this
commit,

> $XDG_DATA_HOME defines the base directory relative to which
> user-specific data files should be stored. If $XDG_DATA_HOME is either
> not set **or empty**, a default equal to $HOME/.local/share should be
> used.

and

> $XDG_CACHE_HOME defines the base directory relative to which
> user-specific non-essential data files should be stored. If
> $XDG_CACHE_HOME is either not set **or empty**, a default equal to
> $HOME/.cache should be used.

(emphasis mine)

In addition to the case mentioned in the linked issue, all other uses of
XDG environment variables were corrected.
2024-08-19 23:30:14 -07:00

67 lines
2.6 KiB
Zig

const std = @import("../std.zig");
const builtin = @import("builtin");
const unicode = std.unicode;
const mem = std.mem;
const fs = std.fs;
const native_os = builtin.os.tag;
const posix = std.posix;
pub const GetAppDataDirError = error{
OutOfMemory,
AppDataDirUnavailable,
};
/// Caller owns returned memory.
/// TODO determine if we can remove the allocator requirement
pub fn getAppDataDir(allocator: mem.Allocator, appname: []const u8) GetAppDataDirError![]u8 {
switch (native_os) {
.windows => {
const local_app_data_dir = std.process.getEnvVarOwned(allocator, "LOCALAPPDATA") catch |err| switch (err) {
error.OutOfMemory => |e| return e,
else => return error.AppDataDirUnavailable,
};
defer allocator.free(local_app_data_dir);
return fs.path.join(allocator, &[_][]const u8{ local_app_data_dir, appname });
},
.macos => {
const home_dir = posix.getenv("HOME") orelse {
// TODO look in /etc/passwd
return error.AppDataDirUnavailable;
};
return fs.path.join(allocator, &[_][]const u8{ home_dir, "Library", "Application Support", appname });
},
.linux, .freebsd, .netbsd, .dragonfly, .openbsd, .solaris, .illumos => {
if (posix.getenv("XDG_DATA_HOME")) |xdg| {
if (xdg.len > 0) {
return fs.path.join(allocator, &[_][]const u8{ xdg, appname });
}
}
const home_dir = posix.getenv("HOME") orelse {
// TODO look in /etc/passwd
return error.AppDataDirUnavailable;
};
return fs.path.join(allocator, &[_][]const u8{ home_dir, ".local", "share", appname });
},
.haiku => {
var dir_path_buf: [std.fs.max_path_bytes]u8 = undefined;
const rc = std.c.find_directory(.B_USER_SETTINGS_DIRECTORY, -1, true, &dir_path_buf, dir_path_buf.len);
const settings_dir = try allocator.dupeZ(u8, mem.sliceTo(&dir_path_buf, 0));
defer allocator.free(settings_dir);
switch (rc) {
0 => return fs.path.join(allocator, &[_][]const u8{ settings_dir, appname }),
else => return error.AppDataDirUnavailable,
}
},
else => @compileError("Unsupported OS"),
}
}
test getAppDataDir {
if (native_os == .wasi) return error.SkipZigTest;
// We can't actually validate the result
const dir = getAppDataDir(std.testing.allocator, "zig") catch return;
defer std.testing.allocator.free(dir);
}