Updates to comparable_patch.sh to support Windows vendor neutral comparison

tooling/ReproducibleBuilds.MD

@@ -39,12 +39,79 @@ remove any Signatures from the executeables.
 
 ## Comparable Build Tools
 
-1. comparable_patch.sh : Patches a JDK folder to enable "Comparable" comparison of two different Vendor JDK builds.
+comparable_patch.sh : Patches a JDK folder to enable "Comparable" comparison of two different Vendor JDK builds.
 The patching process involves:
 
 - Expanding all zips and jmods, so executeables can be processed to remove signatures prior to comaprison.
 - Removing Signatures (Windows & MacOS).
 - Neutralise VS_VERSION_INFO Vendor strings (Windows).
 - Remove non-comparable CRC generated uuid values, which are binary values based on the hash of the content (Windows & MacOS).
 - Remove Vendor strings embedded in executables, classes and text files.
+- Remove module-info differences due to "hash" of Signed module executables
 - Remove any non-deterministic build process artifact strings, like Manifest Created-By stamps.
+
+### How to setup and run comparable_patch.sh on Windows
+
+#### Tooling setup:
+
+1. The comparable patch tools, tooling/src/c/WindowsUpdateVsVersionInfo.c and src/java/temurin/tools/BinRepl.java need compiling
+before the comparable_patch.sh can be run
+
+2. Compile tooling/src/c/WindowsUpdateVsVersionInfo.c :
+
+- Ensure VS2022 SDK is installed and on PATH
+- Compile:
+  - cd tooling/src/c
+  - cl WindowsUpdateVsVersionInfo.c version.lib
+
+3. Compile src/java/temurin/tools/BinRepl.java :
+
+- Ensure suitable JDK on PATH
+- cd tooling/src/java
+- javac temurin/tools/BinRepl.java
+
+4. Setting environment within a CYGWIN shell :
+
+- For BinRepl : export CLASSPATH=<temurin-build>/tooling/src/java:$CLASSPATH
+- For WindowsUpdateVsVersionInfo.exe : export PATH=<temurin-build>/tooling/src/c:$PATH
+- For dumpbin.exe MSVC tool : export PATH=/cygdrive/c/progra\~1/micros\~2/2022/Community/VC/Tools/MSVC/14.37.32822/bin/Hostx64/x64:$PATH
+- For running BinRepl java : export PATH=<jdk>/bin:$PATH
+
+#### Running comparable_patch.sh:
+
+1. Unzip your JDK archive into a directory (eg.jdk1)
+
+2. Run comparable_patch.sh
+
+```bash
+bash comparable_patch.sh <jdk_home_dir> <version_str> <vendor_name> <vendor_url> <vendor_bug_url> <vendor_vm_bug_url>
+```
+
+The Vendor strings and urls can be found by running your jdk's "java -XshowSettings":
+
+```java
+java -XshowSettings:
+...
+    java.vendor = Eclipse Adoptium
+    java.vendor.url = https://adoptium.net/
+    java.vendor.url.bug = https://github.com/adoptium/adoptium-support/issues
+    java.vendor.version = Temurin-21.0.1+12
+...
+```
+
+eg.
+
+```bash
+bash comparable_patch.sh jdk1/jdk-21.0.1+12 "Temurin-21.0.1+12" "Eclipse Adoptium" "https://adoptium.net/" "https://github.com/adoptium/adoptium-support/issues" "https://github.com/adoptium/adoptium-support/issues"
+```
+
+3. Unzip the other Vendor JDK to compare with, say into "jdk2", and run a similar comparable_patch.sh
+for that Vendor branding
+
+4. Diff recursively the now Vendor neutralized jdk directories
+
+```bash
+diff -r jdk1 jdk2
+```
+
+The diff should be "identical" if the two Vendor JDK's are "Comparable", ie."Identical except for the Vendor Branding"