Bug 1525968 - Make local development artifact builds on Android download full build symbols. r=froydnj

We produce two types of build symbol archives in automation:

- "crashreporter-symbols.zip" contains Breakpad-format .sym files
- "crashreporter-symbols-full.zip" contains Breakpad-format .sym files
  and compressed ELF debug symbol .dbg.gz files

Right now, `--enable-artifact-build-symbols` from Bug 1305502
downloads only "crashreporter-symbols.zip".

The Android Studio version of lldb, currently 7.0.0, doesn't support
Breakpad-format .sym files. It does support (uncompressed) ELF debug
symbols.  (Note that gdb isn't supported on Android and hasn't been for
some time.)

This makes ` --enable-artifact-build-symbols` download the full
symbols for Android builds that aren't in automation, to be useful for
debugging Android builds with lldb locally.

Differential Revision: https://phabricator.services.mozilla.com/D19091

--HG--
extra : moz-landing-system : lando

moz.configure

@@ -31,9 +31,18 @@ imply_option('--enable-artifact-build-symbols',
 option('--enable-artifact-build-symbols', nargs='?', choices=('full',),
        help='Download symbols when artifact builds are enabled.')
 
+@depends('--enable-artifact-build-symbols', 'MOZ_AUTOMATION', target)
+def enable_artifact_build_symbols(value, automation, target):
+    if len(value):
+        return value[0]
+    if bool(value):
+        if target.os == 'Android' and not automation:
+            return 'full'
+        return True
+    return None
+
 set_config('MOZ_ARTIFACT_BUILD_SYMBOLS',
-           depends('--enable-artifact-build-symbols')(
-               lambda v: v[0] if len(v) else (bool(v) or None)))
+           enable_artifact_build_symbols)
 
 @depends('--enable-artifact-builds')
 def imply_disable_compile_environment(value):

python/mozbuild/mozbuild/artifacts.py

@@ -286,10 +286,15 @@ class ArtifactJob(object):
                              'matched an archive path.'.format(
                                  patterns=LinuxArtifactJob.test_artifact_patterns))
 
-    def process_symbols_archive(self, filename, processed_filename):
+    def process_symbols_archive(self, filename, processed_filename, skip_compressed=False):
         with JarWriter(file=processed_filename, compress_level=5) as writer:
             reader = JarReader(filename)
             for filename in reader.entries:
+                if skip_compressed and filename.endswith('.gz'):
+                    self.log(logging.INFO, 'artifact',
+                             {'filename': filename},
+                             'Skipping compressed ELF debug symbol file {filename}')
+                    continue
                 destpath = mozpath.join('crashreporter-symbols', filename)
                 self.log(logging.INFO, 'artifact',
                          {'destpath': destpath},
@@ -334,6 +339,35 @@ class AndroidArtifactJob(ArtifactJob):
                 basename = mozpath.join(basedir, basename)
                 writer.add(basename.encode('utf-8'), f.open())
 
+    def process_symbols_archive(self, filename, processed_filename):
+        ArtifactJob.process_symbols_archive(self, filename, processed_filename, skip_compressed=True)
+
+        if self._symbols_archive_suffix != 'crashreporter-symbols-full.zip':
+            return
+
+        import gzip
+
+        with JarWriter(file=processed_filename, compress_level=5) as writer:
+            reader = JarReader(filename)
+            for filename in reader.entries:
+                if not filename.endswith('.gz'):
+                    continue
+
+                # Uncompress "libxul.so/D3271457813E976AE7BF5DAFBABABBFD0/libxul.so.dbg.gz" into "libxul.so.dbg".
+                #
+                # After `settings append target.debug-file-search-paths /path/to/topobjdir/dist/crashreporter-symbols`,
+                # Android Studio's lldb (7.0.0, at least) will find the ELF debug symbol files.
+                #
+                # There are other paths that will work but none seem more desireable.  See
+                # https://github.com/llvm-mirror/lldb/blob/882670690ca69d9dd96b7236c620987b11894af9/source/Host/common/Symbols.cpp#L324.
+                basename = os.path.basename(filename).replace('.gz', '')
+                destpath = mozpath.join('crashreporter-symbols', basename)
+                self.log(logging.INFO, 'artifact',
+                         {'destpath': destpath},
+                         'Adding uncompressed ELF debug symbol file {destpath} to processed archive')
+                writer.add(destpath.encode('utf-8'),
+                           gzip.GzipFile(fileobj=reader[filename].uncompressed_data))
+
 
 class LinuxArtifactJob(ArtifactJob):
     package_re = r'public/build/target\.tar\.bz2'