From 3a8b15a4f48918eb770b50d3cb842b1ab26e84aa Mon Sep 17 00:00:00 2001
From: mcpkdot <mcpkdot@gmail.com>
Date: Tue, 18 Feb 2025 21:11:32 +0900
Subject: [PATCH] feat(build): linux binaries for arm64

make the linux binaries work in arm64 via universal binaries

BREAKING CHANGE: does not use GCC

Temporary change as I couldn't get GCC to work in my computer.
To use GCC, go to GenerateLibs.groovy and remove line 174.
---
 README.md                                     |  8 ++++++-
 .../groovy/tool/generator/GenerateLibs.groovy | 21 ++++++++++++++++---
 imgui-app/build.gradle                        |  2 +-
 3 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 51a3c292..4450f6b8 100644
--- a/README.md
+++ b/README.md
@@ -376,6 +376,12 @@ Ensure you've downloaded git submodules. That could be achieved:
  - Install dependencies: `openjdk8`, `mingw-w64-gcc`, `ant`. (Package names could vary from system to system.)
  - Build with: `./gradlew imgui-binding:generateLibs -Denvs=linux -Dlocal`
  - Run with: `./gradlew example:run -PlibPath=../imgui-binding/build/libsNative/linux64`
+
+### Linux (arm64)
+
+- Check dependencies from "Linux" section and make sure you have them installed.
+- Build with: `./gradlew imgui-binding:generateLibs -Denvs=linuxarm64 -Dlocal`
+- Run with: `./gradlew example:run -PlibPath=../imgui-binding/build/libsNative/linuxarm64`
  
 ### macOS
 
@@ -389,7 +395,7 @@ Ensure you've downloaded git submodules. That could be achieved:
  - Build with: `./gradlew imgui-binding:generateLibs -Denvs=macosarm64 -Dlocal`
  - Run with: `./gradlew example:run -PlibPath=../imgui-binding/build/libsNative/macosxarm64`
 
-In `envs` parameter next values could be used `windows`, `linux` or `macos` or `macosarm64`.
+In `envs` parameter next values could be used `windows`, `linux`, `linuxarm64`, `macos` or `macosarm64`.
 
 `-Dlocal` is optional and means that natives will be built under the `./imgui-binding/build/` folder. Otherwise `/tmp/imgui` folder will be used.
 
diff --git a/buildSrc/src/main/groovy/tool/generator/GenerateLibs.groovy b/buildSrc/src/main/groovy/tool/generator/GenerateLibs.groovy
index 3a0c000c..fffa3c34 100644
--- a/buildSrc/src/main/groovy/tool/generator/GenerateLibs.groovy
+++ b/buildSrc/src/main/groovy/tool/generator/GenerateLibs.groovy
@@ -32,6 +32,7 @@ class GenerateLibs extends DefaultTask {
     private final String[] buildEnvs = System.getProperty('envs')?.split(',')
     private final boolean forWindows = buildEnvs?.contains('windows')
     private final boolean forLinux = buildEnvs?.contains('linux')
+    private final boolean forLinuxArm64 = buildEnvs?.contains('linuxarm64')
     private final boolean forMac = buildEnvs?.contains('macos')
     private final boolean forMacArm64 = buildEnvs?.contains('macosarm64')
 
@@ -113,9 +114,11 @@ class GenerateLibs extends DefaultTask {
         }
 
         if (forLinux) {
-            def linux64 = BuildTarget.newDefaultTarget(Os.Linux, Architecture.Bitness._64)
-            addFreeTypeIfEnabled(linux64)
-            buildTargets += linux64
+            buildTargets += createLinuxTarget(Architecture.x86)
+        }
+
+        if (forLinuxArm64) {
+            buildTargets += createLinuxTarget(Architecture.ARM)
         }
 
         if (forMac) {
@@ -137,6 +140,8 @@ class GenerateLibs extends DefaultTask {
             BuildExecutor.executeAnt(jniDir + '/build-windows64.xml', commonParams)
         if (forLinux)
             BuildExecutor.executeAnt(jniDir + '/build-linux64.xml', commonParams)
+        if (forLinuxArm64)
+            BuildExecutor.executeAnt(jniDir + '/build-linuxarm64.xml', commonParams)
         if (forMac)
             BuildExecutor.executeAnt(jniDir + '/build-macosx64.xml', commonParams)
         if (forMacArm64)
@@ -148,6 +153,8 @@ class GenerateLibs extends DefaultTask {
             checkLibExist("windows64/imgui-java64.dll")
         if (forLinux)
             checkLibExist("linux64/libimgui-java64.so")
+        if (forLinuxArm64)
+            checkLibExist("linuxarm64/libimgui-java64.so")
         if (forMac)
             checkLibExist("macosx64/libimgui-java64.dylib")
         if (forMacArm64)
@@ -162,6 +169,14 @@ class GenerateLibs extends DefaultTask {
         }
     }
 
+    BuildTarget createLinuxTarget(Architecture arch) {
+        def linuxTarget = BuildTarget.newDefaultTarget(Os.Linux, Architecture.Bitness._64, arch)
+        linuxTarget.compilerPrefix = "" // TODO: test with GNU gcc
+        linuxTarget.libName = "libimgui-java64.so" // Lib for arm64 will be named the same for consistency
+        addFreeTypeIfEnabled(linuxTarget)
+        return linuxTarget
+    }
+
     BuildTarget createMacTarget(Architecture arch) {
         def minMacOsVersion = '10.15'
         def macTarget = BuildTarget.newDefaultTarget(Os.MacOsX, Architecture.Bitness._64, arch)
diff --git a/imgui-app/build.gradle b/imgui-app/build.gradle
index 5ed4355d..718827f2 100644
--- a/imgui-app/build.gradle
+++ b/imgui-app/build.gradle
@@ -19,7 +19,7 @@ dependencies {
     api 'org.lwjgl:lwjgl-glfw'
     api 'org.lwjgl:lwjgl-opengl'
 
-    ['natives-linux', 'natives-windows', 'natives-macos', 'natives-macos-arm64'].each {
+    ['natives-linux', 'natives-linux-arm64', 'natives-windows', 'natives-macos', 'natives-macos-arm64'].each {
         api "org.lwjgl:lwjgl::$it"
         api "org.lwjgl:lwjgl-glfw::$it"
         api "org.lwjgl:lwjgl-opengl::$it"