Rewrite how to generate apexkeys.txt

Instead of listing all apexes in the source tree, now each apex emits
its own fragment for apexkeys.txt, which is pointed by
LOCAL_APEX_KEYS_FILE. Makefile collects apexkeys.txt from installed apex
files. This is to avoid listing unrelated apexes (not installed,
testdata, unexported namespaces, etc.)

Bug: 304914238
Test: m apexkeys.txt
Test: m blueprint-tests
Change-Id: Iefbe6e486cb418955584ad1a282455307e90be95
diff --git a/apex/androidmk.go b/apex/androidmk.go
index 2f5d8d4..6136cbd 100644
--- a/apex/androidmk.go
+++ b/apex/androidmk.go
@@ -260,6 +260,7 @@
 				fmt.Fprintln(w, "LOCAL_SOONG_INSTALL_PAIRS :=", a.outputFile.String()+":"+a.installedFile.String())
 				fmt.Fprintln(w, "LOCAL_SOONG_INSTALL_SYMLINKS := ", strings.Join(a.compatSymlinks.Strings(), " "))
 			}
+			fmt.Fprintln(w, "LOCAL_APEX_KEY_PATH := ", a.apexKeysPath.String())
 
 			// Because apex writes .mk with Custom(), we need to write manually some common properties
 			// which are available via data.Entries
diff --git a/apex/apex.go b/apex/apex.go
index f903373..adabdee 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -454,6 +454,9 @@
 	// Path where this APEX was installed.
 	installedFile android.InstallPath
 
+	// fragment for this apex for apexkeys.txt
+	apexKeysPath android.WritablePath
+
 	// Installed locations of symlinks for backward compatibility.
 	compatSymlinks android.InstallPaths
 
@@ -1923,6 +1926,7 @@
 
 		a.filesInfo = append(a.filesInfo, fileInfo)
 	}
+	a.apexKeysPath = writeApexKeys(ctx, a)
 }
 
 func (a *apexBundle) setCompression(ctx android.ModuleContext) {
diff --git a/apex/apex_test.go b/apex/apex_test.go
index e70d3af..97cc3cb 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -9078,8 +9078,8 @@
 		}
 	`)
 
-	apexKeysText := ctx.SingletonForTests("apex_keys_text")
-	content := apexKeysText.MaybeDescription("apexkeys.txt").BuildParams.Args["content"]
+	myapex := ctx.ModuleForTests("myapex", "android_common_myapex")
+	content := myapex.Output("apexkeys.txt").BuildParams.Args["content"]
 	ensureContains(t, content, `name="myapex.apex" public_key="vendor/foo/devkeys/testkey.avbpubkey" private_key="vendor/foo/devkeys/testkey.pem" container_certificate="vendor/foo/devkeys/test.x509.pem" container_private_key="vendor/foo/devkeys/test.pk8" partition="system" sign_tool="sign_myapex"`)
 }
 
@@ -9119,10 +9119,10 @@
 		}
 	`)
 
-	apexKeysText := ctx.SingletonForTests("apex_keys_text")
-	content := apexKeysText.MaybeDescription("apexkeys.txt").BuildParams.Args["content"]
+	content := ctx.ModuleForTests("myapex", "android_common_myapex").Output("apexkeys.txt").BuildParams.Args["content"]
+	ensureContains(t, content, `name="myapex.apex" public_key="vendor/foo/devkeys/testkey.avbpubkey" private_key="vendor/foo/devkeys/testkey.pem" container_certificate="vendor/foo/devkeys/test.x509.pem" container_private_key="vendor/foo/devkeys/test.pk8" partition="system" sign_tool="sign_myapex"`)
+	content = ctx.ModuleForTests("myapex_set", "android_common_myapex_set").Output("apexkeys.txt").BuildParams.Args["content"]
 	ensureContains(t, content, `name="myapex_set.apex" public_key="PRESIGNED" private_key="PRESIGNED" container_certificate="PRESIGNED" container_private_key="PRESIGNED" partition="system"`)
-	ensureContains(t, content, `name="myapex.apex" public_key="PRESIGNED" private_key="PRESIGNED" container_certificate="PRESIGNED" container_private_key="PRESIGNED" partition="system"`)
 }
 
 func TestAllowedFiles(t *testing.T) {
diff --git a/apex/builder.go b/apex/builder.go
index 729917f..d75cc1d 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -948,6 +948,8 @@
 
 	// installed-files.txt is dist'ed
 	a.installedFilesFile = a.buildInstalledFilesFile(ctx, a.outputFile, imageDir)
+
+	a.apexKeysPath = writeApexKeys(ctx, a)
 }
 
 // getCertificateAndPrivateKey retrieves the cert and the private key that will be used to sign
diff --git a/apex/key.go b/apex/key.go
index fe8bf30..2405e98 100644
--- a/apex/key.go
+++ b/apex/key.go
@@ -16,8 +16,6 @@
 
 import (
 	"fmt"
-	"sort"
-	"strings"
 
 	"android/soong/android"
 	"android/soong/bazel"
@@ -33,7 +31,6 @@
 
 func registerApexKeyBuildComponents(ctx android.RegistrationContext) {
 	ctx.RegisterModuleType("apex_key", ApexKeyFactory)
-	ctx.RegisterParallelSingletonType("apex_keys_text", apexKeysTextFactory)
 }
 
 type apexKey struct {
@@ -126,7 +123,7 @@
 	}
 }
 
-func apexKeyEntryFor(ctx android.SingletonContext, module android.Module) apexKeyEntry {
+func apexKeyEntryFor(ctx android.ModuleContext, module android.Module) apexKeyEntry {
 	switch m := module.(type) {
 	case *apexBundle:
 		pem, key := m.getCertificateAndPrivateKey(ctx)
@@ -156,58 +153,11 @@
 	panic(fmt.Errorf("unknown type(%t) for apexKeyEntry", module))
 }
 
-// //////////////////////////////////////////////////////////////////////
-// apex_keys_text
-type apexKeysText struct {
-	output android.OutputPath
-}
-
-func (s *apexKeysText) GenerateBuildActions(ctx android.SingletonContext) {
-	s.output = android.PathForOutput(ctx, "apexkeys.txt")
-
-	apexKeyMap := make(map[string]apexKeyEntry)
-	ctx.VisitAllModules(func(module android.Module) {
-		if m, ok := module.(*apexBundle); ok && m.Enabled() && m.installable() {
-			apexKeyMap[m.Name()] = apexKeyEntryFor(ctx, m)
-		}
-	})
-
-	// Find prebuilts and let them override apexBundle if they are preferred
-	ctx.VisitAllModules(func(module android.Module) {
-		if m, ok := module.(*Prebuilt); ok && m.Enabled() && m.installable() &&
-			m.Prebuilt().UsePrebuilt() {
-			apexKeyMap[m.BaseModuleName()] = apexKeyEntryFor(ctx, m)
-		}
-	})
-
-	// Find apex_set and let them override apexBundle or prebuilts. This is done in a separate pass
-	// so that apex_set are not overridden by prebuilts.
-	ctx.VisitAllModules(func(module android.Module) {
-		if m, ok := module.(*ApexSet); ok && m.Enabled() {
-			apexKeyMap[m.BaseModuleName()] = apexKeyEntryFor(ctx, m)
-		}
-	})
-
-	// iterating over map does not give consistent ordering in golang
-	var moduleNames []string
-	for key, _ := range apexKeyMap {
-		moduleNames = append(moduleNames, key)
-	}
-	sort.Strings(moduleNames)
-
-	var filecontent strings.Builder
-	for _, name := range moduleNames {
-		filecontent.WriteString(apexKeyMap[name].String())
-	}
-	android.WriteFileRule(ctx, s.output, filecontent.String())
-}
-
-func apexKeysTextFactory() android.Singleton {
-	return &apexKeysText{}
-}
-
-func (s *apexKeysText) MakeVars(ctx android.MakeVarsContext) {
-	ctx.Strict("SOONG_APEX_KEYS_FILE", s.output.String())
+func writeApexKeys(ctx android.ModuleContext, module android.Module) android.WritablePath {
+	path := android.PathForModuleOut(ctx, "apexkeys.txt")
+	entry := apexKeyEntryFor(ctx, module)
+	android.WriteFileRuleVerbatim(ctx, path, entry.String())
+	return path
 }
 
 // For Bazel / bp2build
diff --git a/apex/prebuilt.go b/apex/prebuilt.go
index 1a90c3a..7a9d23e 100644
--- a/apex/prebuilt.go
+++ b/apex/prebuilt.go
@@ -60,6 +60,9 @@
 	installedFile   android.InstallPath
 	outputApex      android.WritablePath
 
+	// fragment for this apex for apexkeys.txt
+	apexKeysPath android.WritablePath
+
 	// A list of apexFile objects created in prebuiltCommon.initApexFilesForAndroidMk which are used
 	// to create make modules in prebuiltCommon.AndroidMkEntries.
 	apexFilesForAndroidMk []apexFile
@@ -238,6 +241,7 @@
 					entries.AddStrings("LOCAL_SOONG_INSTALL_SYMLINKS", p.compatSymlinks.Strings()...)
 					entries.SetBoolIfTrue("LOCAL_UNINSTALLABLE_MODULE", !p.installable())
 					entries.AddStrings("LOCAL_OVERRIDES_MODULES", p.prebuiltCommonProperties.Overrides...)
+					entries.SetString("LOCAL_APEX_KEY_PATH", p.apexKeysPath.String())
 					p.addRequiredModules(entries)
 				},
 			},
@@ -759,6 +763,7 @@
 }
 
 func (p *Prebuilt) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	p.apexKeysPath = writeApexKeys(ctx, p)
 	// TODO(jungjw): Check the key validity.
 	p.inputApex = android.OptionalPathForModuleSrc(ctx, p.prebuiltCommonProperties.Selected_apex).Path()
 	p.installDir = android.PathForModuleInstall(ctx, "apex")
@@ -975,6 +980,7 @@
 }
 
 func (a *ApexSet) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	a.apexKeysPath = writeApexKeys(ctx, a)
 	a.installFilename = a.InstallFilename()
 	if !strings.HasSuffix(a.installFilename, imageApexSuffix) && !strings.HasSuffix(a.installFilename, imageCapexSuffix) {
 		ctx.ModuleErrorf("filename should end in %s or %s for apex_set", imageApexSuffix, imageCapexSuffix)