Revert "Revert "Automated NDK API coverage used by Mainline modules build integration.""

This reverts commit 556b2ad77e31956cbc2a329553c8ad7692639708.

Original change-id: Ib1b2f0dd2f9ae85b1545c6cc5bb4c5bbdfac1c15

Reason for revert: Add excutable permission to the gen_ndk_backedby_apex.sh.

Test: TARGET_BUILD_APPS=com.android.adbd m dist apps_only

Change-Id: Ib587ba200cd7f2f61d478452b43c329d72b2de06
diff --git a/apex/androidmk.go b/apex/androidmk.go
index 61b9dad..de04d52 100644
--- a/apex/androidmk.go
+++ b/apex/androidmk.go
@@ -422,12 +422,21 @@
 					fmt.Fprintf(w, dist)
 				}
 
-				if a.coverageOutputPath.String() != "" {
+				if a.apisUsedByModuleFile.String() != "" {
 					goal := "apps_only"
-					distFile := a.coverageOutputPath.String()
+					distFile := a.apisUsedByModuleFile.String()
 					fmt.Fprintf(w, "ifneq (,$(filter $(my_register_name),$(TARGET_BUILD_APPS)))\n"+
 						" $(call dist-for-goals,%s,%s:ndk_apis_usedby_apex/$(notdir %s))\n"+
-						"endif",
+						"endif\n",
+						goal, distFile, distFile)
+				}
+
+				if a.apisBackedByModuleFile.String() != "" {
+					goal := "apps_only"
+					distFile := a.apisBackedByModuleFile.String()
+					fmt.Fprintf(w, "ifneq (,$(filter $(my_register_name),$(TARGET_BUILD_APPS)))\n"+
+						" $(call dist-for-goals,%s,%s:ndk_apis_backedby_apex/$(notdir %s))\n"+
+						"endif\n",
 						goal, distFile, distFile)
 				}
 			}
diff --git a/apex/apex.go b/apex/apex.go
index 1d4f7b2..a405721 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -355,7 +355,8 @@
 	prebuiltFileToDelete string
 
 	// Path of API coverage generate file
-	coverageOutputPath android.ModuleOutPath
+	apisUsedByModuleFile   android.ModuleOutPath
+	apisBackedByModuleFile android.ModuleOutPath
 }
 
 // apexFileClass represents a type of file that can be included in APEX.
diff --git a/apex/builder.go b/apex/builder.go
index 66eaff1..1ec59a8 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -686,7 +686,7 @@
 		implicitInputs = append(implicitInputs, unsignedOutputFile)
 
 		// Run coverage analysis
-		apisUsedbyOutputFile := android.PathForModuleOut(ctx, a.Name()+".txt")
+		apisUsedbyOutputFile := android.PathForModuleOut(ctx, a.Name()+"_using.txt")
 		ctx.Build(pctx, android.BuildParams{
 			Rule:        generateAPIsUsedbyApexRule,
 			Implicits:   implicitInputs,
@@ -697,7 +697,19 @@
 				"readelf":   "${config.ClangBin}/llvm-readelf",
 			},
 		})
-		a.coverageOutputPath = apisUsedbyOutputFile
+		a.apisUsedByModuleFile = apisUsedbyOutputFile
+
+		apisBackedbyOutputFile := android.PathForModuleOut(ctx, a.Name()+"_backing.txt")
+		ndkLibraryList := android.PathForSource(ctx, "system/core/rootdir/etc/public.libraries.android.txt")
+		rule := android.NewRuleBuilder(pctx, ctx)
+		rule.Command().
+			Tool(android.PathForSource(ctx, "build/soong/scripts/gen_ndk_backedby_apex.sh")).
+			Text(imageDir.String()).
+			Implicits(implicitInputs).
+			Output(apisBackedbyOutputFile).
+			Input(ndkLibraryList)
+		rule.Build("ndk_backedby_list", "Generate API libraries backed by Apex")
+		a.apisBackedByModuleFile = apisBackedbyOutputFile
 
 		bundleConfig := a.buildBundleConfig(ctx)
 
diff --git a/scripts/gen_ndk_backedby_apex.sh b/scripts/gen_ndk_backedby_apex.sh
new file mode 100755
index 0000000..e0da602
--- /dev/null
+++ b/scripts/gen_ndk_backedby_apex.sh
@@ -0,0 +1,55 @@
+#!/bin/bash -e
+
+# Copyright 2020 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Generates NDK API txt file used by Mainline modules. NDK APIs would have value
+# "UND" in Ndx column and have suffix "@LIB_NAME" in Name column.
+# For example, current line llvm-readelf output is:
+# 1: 00000000     0     FUNC      GLOBAL  DEFAULT   UND   dlopen@LIBC
+# After the parse function below "dlopen" would be write to the output file.
+printHelp() {
+    echo "**************************** Usage Instructions ****************************"
+    echo "This script is used to generate the Mainline modules backed-by NDK symbols."
+    echo ""
+    echo "To run this script use: ./ndk_backedby_module.sh \$BINARY_IMAGE_DIRECTORY \$OUTPUT_FILE_PATH \$NDK_LIB_NAME_LIST"
+    echo "For example: If all the module image files that you would like to run is under directory '/myModule' and output write to /backedby.txt then the command would be:"
+    echo "./ndk_usedby_module.sh /myModule /backedby.txt /ndkLibList.txt"
+    echo "If the module1 is backing lib1 then the backedby.txt would contains: "
+    echo "lib1"
+}
+
+genBackedByList() {
+  dir="$1"
+  [[ ! -e "$2" ]] && echo "" >> "$2"
+  while IFS= read -r line
+  do
+    soFileName=$(echo "$line" | sed 's/\(.*so\).*/\1/')
+    if [[ ! -z "$soFileName" && "$soFileName" != *"#"* ]]
+    then
+      find "$dir" -type f -name "$soFileName" -exec echo "$soFileName" >> "$2" \;
+    fi
+  done < "$3"
+}
+
+if [[ "$1" == "help" ]]
+then
+  printHelp
+elif [[ "$#" -ne 3 ]]
+then
+  echo "Wrong argument length. Expecting 3 argument representing image file directory, output path, path to ndk library list."
+else
+  [[ -e "$2" ]] && rm "$2"
+  genBackedByList "$1" "$2" "$3"
+fi