From 855955bb3de853b165fd292468c40e20e179ecb1 Mon Sep 17 00:00:00 2001
From: dragonmacher <48328597+dragonmacher@users.noreply.github.com>
Date: Mon, 24 Feb 2020 11:00:51 -0500
Subject: [PATCH] GT-3547 - Patch dir fix - review fixes

---
 .../ghidra/util/classfinder/ClassJar.java     | 18 +++++++++-------
 .../src/main/java/ghidra/GhidraLauncher.java  |  4 ++--
 GhidraBuild/patch/README.txt                  | 21 +++++++++----------
 3 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassJar.java b/Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassJar.java
index 96da614379..48b9be6f14 100644
--- a/Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassJar.java
+++ b/Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassJar.java
@@ -94,21 +94,24 @@ class ClassJar extends ClassLocation {
 		//
 
 		//
-		// Dev Mode
+		// Dev Mode - don't scan 3rd-party jar files
 		// 
 		if (pathName.contains("ExternalLibraries")) {
 			return true;
 		}
 
 		//
-		// Dev and Production Mode
-		//
-		String forwardSlashedPathName = pathName.replaceAll("\\\\", "/");
-		if (isUserPluginJar(forwardSlashedPathName)) {
+		// Dev Mode - let everything else through
+		// 
+		if (SystemUtilities.isInDevelopmentMode()) {
 			return false;
 		}
 
-		if (SystemUtilities.isInDevelopmentMode()) {
+		//
+		// Production Mode - old style (before Extensions) of user contributions
+		//
+		String forwardSlashedPathName = pathName.replaceAll("\\\\", "/");
+		if (isUserPluginJar(forwardSlashedPathName)) {
 			return false;
 		}
 
@@ -120,12 +123,13 @@ class ClassJar extends ClassLocation {
 		}
 
 		//
-		// Production Mode - In production, only module lib jar files are scanned.
+		// Production Mode - In production, only module lib jar files are scanned
 		//
 		if (isModuleDependencyJar(forwardSlashedPathName)) {
 			return false;
 		}
 
+		// this is typically a 3rd-party jar file
 		return true;
 	}
 
diff --git a/Ghidra/Framework/Utility/src/main/java/ghidra/GhidraLauncher.java b/Ghidra/Framework/Utility/src/main/java/ghidra/GhidraLauncher.java
index 40d0aaf7fa..8db165297e 100644
--- a/Ghidra/Framework/Utility/src/main/java/ghidra/GhidraLauncher.java
+++ b/Ghidra/Framework/Utility/src/main/java/ghidra/GhidraLauncher.java
@@ -87,10 +87,10 @@ public class GhidraLauncher {
 	 * the classpath.
 	 * 
 	 * @param pathList The list of paths to add to
-	 * @param patchDir The application installation directory
+	 * @param patchDir The application installation directory; may be null
 	 */
 	private static void addPatchPaths(List<String> pathList, ResourceFile patchDir) {
-		if (!patchDir.exists()) {
+		if (patchDir == null || !patchDir.exists()) {
 			return;
 		}
 
diff --git a/GhidraBuild/patch/README.txt b/GhidraBuild/patch/README.txt
index 70fbdca2c3..c49fd4483c 100644
--- a/GhidraBuild/patch/README.txt
+++ b/GhidraBuild/patch/README.txt
@@ -1,13 +1,12 @@
-Compiled Java class files, either inside of a jar file or in a directory structure may be inserted
-into this directory.   This directory and the contained jar files will be prepended to
-the classpath, allowing them to override any existing classes in any module (except those from
-the Utility module).
-
-The jar files will be sorted by name before being added to the classpath in order to present
-predictable class loading between Ghidra runs.  This directory will be prepended on the classpath
-before any jar files, given the classes in this directory precedence over the jar files.
-
-The class files in this directory must be in a directory structure that matches their respective
-packages.
+This directory exits so that Ghidra releases can be patched, or overridden. 
+Classes or jar files placed in this directory will found and loaded 
+*before* the classes that exist in the release jar files. One exception 
+is that classes in the Utility module can not be patched in this way.
 
+The jar files will be sorted by name before being prepended to the classpath 
+in order to have predictable class loading between Ghidra runs.  This patch 
+directory will be the very first patch entry on the classpath such that any 
+individual classes will be found before classes in any of the patch jar files.
 
+The class files in this directory must be in the standard java package 
+directory structure.