Error out if skip_preprocessed_apk_checks is set when it's not necessary

So that we don't erroneously add skip_preprocessed_apk_checks
everywhere.

Bug: 185811447
Test: Presubmits
Change-Id: Icb1c6163d170ca4181c5c6a814b51fda4777746f

scripts/check_prebuilt_presigned_apk.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+
+import subprocess
+import argparse
+import re
+import sys
+import zipfile
+
+def check_target_sdk_less_than_30(args):
+    if not args.aapt2:
+        sys.exit('--aapt2 is required')
+    regex = re.compile(r"targetSdkVersion: *'([0-9]+)'")
+    output = subprocess.check_output([args.aapt2, "dump", "badging", args.apk], text=True)
+    targetSdkVersion = None
+    for line in output.splitlines():
+        match = regex.fullmatch(line.strip())
+        if match:
+            targetSdkVersion = int(match.group(1))
+            break
+
+    if targetSdkVersion is None or targetSdkVersion >= 30:
+        sys.exit(args.apk + ": Prebuilt, presigned apks with targetSdkVersion >= 30 (or a codename targetSdkVersion) must set preprocessed: true in the Android.bp definition (because they must be signed with signature v2, and the build system would wreck that signature otherwise)")
+
+def has_preprocessed_issues(args, *, fail=False):
+    if not args.zipalign:
+        sys.exit('--zipalign is required')
+    ret = subprocess.run([args.zipalign, '-c', '-p', '4', args.apk], stdout=subprocess.DEVNULL).returncode
+    if ret != 0:
+        if fail:
+            sys.exit(args.apk + ': Improper zip alignment')
+        return True
+
+    with zipfile.ZipFile(args.apk) as zf:
+        for info in zf.infolist():
+            if info.filename.startswith('lib/') and info.filename.endswith('.so') and info.compress_type != zipfile.ZIP_STORED:
+                if fail:
+                    sys.exit(args.apk + ': Contains compressed JNI libraries')
+                return True
+            # It's ok for non-privileged apps to have compressed dex files, see go/gms-uncompressed-jni-slides
+            if args.privileged:
+                if info.filename.endswith('.dex') and info.compress_type != zipfile.ZIP_STORED:
+                    if fail:
+                        sys.exit(args.apk + ': Contains compressed dex files and is privileged')
+                    return True
+    return False
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--aapt2', help = "the path to the aapt2 executable")
+    parser.add_argument('--zipalign', help = "the path to the zipalign executable")
+    parser.add_argument('--skip-preprocessed-apk-checks', action = 'store_true', help = "the value of the soong property with the same name")
+    parser.add_argument('--preprocessed', action = 'store_true', help = "the value of the soong property with the same name")
+    parser.add_argument('--privileged', action = 'store_true', help = "the value of the soong property with the same name")
+    parser.add_argument('apk', help = "the apk to check")
+    parser.add_argument('stampfile', help = "a file to touch if successful")
+    args = parser.parse_args()
+
+    if not args.preprocessed:
+        check_target_sdk_less_than_30(args)
+    elif args.skip_preprocessed_apk_checks:
+        if not has_preprocessed_issues(args):
+            sys.exit('This module sets `skip_preprocessed_apk_checks: true`, but does not actually have any issues. Please remove `skip_preprocessed_apk_checks`.')
+    else:
+        has_preprocessed_issues(args, fail=True)
+
+    subprocess.check_call(["touch", args.stampfile])
+
+if __name__ == "__main__":
+    main()

scripts/check_target_sdk_less_than_30.py

@@ -1,30 +0,0 @@
-#!/usr/bin/env python3
-
-import subprocess
-import argparse
-import re
-import sys
-
-def main():
-    parser = argparse.ArgumentParser()
-    parser.add_argument('aapt2', help = "the path to the aapt2 executable")
-    parser.add_argument('apk', help = "the apk to check")
-    parser.add_argument('stampfile', help = "a file to touch if successful")
-    args = parser.parse_args()
-
-    regex = re.compile(r"targetSdkVersion: *'([0-9]+)'")
-    output = subprocess.check_output([args.aapt2, "dump", "badging", args.apk], text=True)
-    targetSdkVersion = None
-    for line in output.splitlines():
-        match = regex.fullmatch(line.strip())
-        if match:
-            targetSdkVersion = int(match.group(1))
-            break
-
-    if targetSdkVersion is None or targetSdkVersion >= 30:
-        sys.exit(args.apk + ": Prebuilt, presigned apks with targetSdkVersion >= 30 (or a codename targetSdkVersion) must set preprocessed: true in the Android.bp definition (because they must be signed with signature v2, and the build system would wreck that signature otherwise)")
-
-    subprocess.check_call(["touch", args.stampfile])
-
-if __name__ == "__main__":
-    main()