From 6265120cd269ba08be46d42bd5e8d88a67c804a6 Mon Sep 17 00:00:00 2001
From: Cole Faust <colefaust@google.com>
Date: Thu, 5 Sep 2024 16:27:56 -0700
Subject: [PATCH] Remove asset dir glob files

I'm rewriting how globs work in soong to make them compatible with
hash-based ninja implementations. As part of this, I'm removing this
unnecessary usage of globs to make them simpler.

In this case, since we're already globbing the directory at analysis
time and causing soong to rerun, we can ensure the aapt2 action also
reruns by putting a hash of the glob results onto the command line.

Bug: 364749114
Test: m framework-res, touch frameworks/base/core/res/assets/test1.txt, m framework-res rebuilt framework-res.apk, rm frameworks/base/core/res/assets/test1.txt, m framework-res rebuilt framework-res.apk again
Change-Id: I4f666367a9a0fd0dfa42dc51ef3a788a02b41747
---
 android/defs.go           |  6 ------
 java/aar.go               | 17 ++++++++++-------
 java/android_resources.go |  9 ---------
 3 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/android/defs.go b/android/defs.go
index 78cdea2ba..9f3fb1ee6 100644
--- a/android/defs.go
+++ b/android/defs.go
@@ -16,7 +16,6 @@ package android
 
 import (
 	"github.com/google/blueprint"
-	"github.com/google/blueprint/bootstrap"
 )
 
 var (
@@ -120,8 +119,3 @@ func init() {
 		return ctx.Config().RBEWrapper()
 	})
 }
-
-// GlobToListFileRule creates a rule that writes a list of files matching a pattern to a file.
-func GlobToListFileRule(ctx ModuleContext, pattern string, excludes []string, file WritablePath) {
-	bootstrap.GlobFile(ctx.blueprintModuleContext(), pattern, excludes, file.String())
-}
diff --git a/java/aar.go b/java/aar.go
index 42866f8b6..cc1ed376f 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -15,10 +15,10 @@
 package java
 
 import (
+	"crypto/sha256"
 	"fmt"
 	"path/filepath"
 	"slices"
-	"strconv"
 	"strings"
 
 	"android/soong/android"
@@ -236,18 +236,20 @@ func (a *aapt) aapt2Flags(ctx android.ModuleContext, sdkContext android.SdkConte
 		rroDirs = append(rroDirs, resRRODirs...)
 	}
 
+	assetDirsHasher := sha256.New()
 	var assetDeps android.Paths
-	for i, dir := range assetDirs {
+	for _, dir := range assetDirs {
 		// Add a dependency on every file in the asset directory.  This ensures the aapt2
 		// rule will be rerun if one of the files in the asset directory is modified.
-		assetDeps = append(assetDeps, androidResourceGlob(ctx, dir)...)
+		dirContents := androidResourceGlob(ctx, dir)
+		assetDeps = append(assetDeps, dirContents...)
 
-		// Add a dependency on a file that contains a list of all the files in the asset directory.
+		// Add a hash of all the files in the asset directory to the command line.
 		// This ensures the aapt2 rule will be run if a file is removed from the asset directory,
 		// or a file is added whose timestamp is older than the output of aapt2.
-		assetFileListFile := android.PathForModuleOut(ctx, "asset_dir_globs", strconv.Itoa(i)+".glob")
-		androidResourceGlobList(ctx, dir, assetFileListFile)
-		assetDeps = append(assetDeps, assetFileListFile)
+		for _, path := range dirContents.Strings() {
+			assetDirsHasher.Write([]byte(path))
+		}
 	}
 
 	assetDirStrings := assetDirs.Strings()
@@ -282,6 +284,7 @@ func (a *aapt) aapt2Flags(ctx android.ModuleContext, sdkContext android.SdkConte
 	linkDeps = append(linkDeps, manifestPath)
 
 	linkFlags = append(linkFlags, android.JoinWithPrefix(assetDirStrings, "-A "))
+	linkFlags = append(linkFlags, fmt.Sprintf("$$(: %x)", assetDirsHasher.Sum(nil)))
 	linkDeps = append(linkDeps, assetDeps...)
 
 	// Returns the effective version for {min|target}_sdk_version
diff --git a/java/android_resources.go b/java/android_resources.go
index 038a260d9..3bb3eb554 100644
--- a/java/android_resources.go
+++ b/java/android_resources.go
@@ -39,15 +39,6 @@ func androidResourceGlob(ctx android.EarlyModuleContext, dir android.Path) andro
 	return ctx.GlobFiles(filepath.Join(dir.String(), "**/*"), androidResourceIgnoreFilenames)
 }
 
-// androidResourceGlobList creates a rule to write the list of files in the given directory, using
-// the standard exclusion patterns for Android resources, to the given output file.
-func androidResourceGlobList(ctx android.ModuleContext, dir android.Path,
-	fileListFile android.WritablePath) {
-
-	android.GlobToListFileRule(ctx, filepath.Join(dir.String(), "**/*"),
-		androidResourceIgnoreFilenames, fileListFile)
-}
-
 type overlayType int
 
 const (