Move to using build-ids to tell GDB about libraries

sky/tools/skydb

Index: sky/tools/skydb
diff --git a/sky/tools/skydb b/sky/tools/skydb
index eb13caab5e1713698fbf16f1adab368dfb55ca58..6e0f300d7e2d0a068aec8ca1a9a1467f289f6c68 100755
--- a/sky/tools/skydb
+++ b/sky/tools/skydb
@@ -40,7 +40,6 @@ DEFAULT_URL = "https://raw.githubusercontent.com/domokit/mojo/master/sky/example
 
 ANDROID_PACKAGE = "org.chromium.mojo.shell"
 ANDROID_ACTIVITY = "%s/.MojoShellActivity" % ANDROID_PACKAGE
-CACHE_LINKS_PATH = '/tmp/mojo_cache_links'
 SYSTEM_LIBS_ROOT_PATH = '/tmp/device_libs'
 
 
@@ -311,8 +310,6 @@ class SkyDebugger(object):
             subprocess.call(['adb', 'forward', '--remove', port_string])
         self.pids = {} # Clear out our pid file.
 
-        self._kill_if_exists('mojo_cache_linker_pid', 'mojo cache linker')
-
     def load_command(self, args):
         if not urlparse.urlparse(args.url_or_path).scheme:
             # The load happens on the remote device, use the remote port.
@@ -425,29 +422,6 @@ class SkyDebugger(object):
         ]
         subprocess.call(['adb', 'logcat', '-d', '-s'] + TAGS)
 
-    def _start_mojo_cache_linker(self, links_path):
-        self._kill_if_exists('mojo_cache_linker_pid', 'mojo cache linker')
-
-        if not os.path.exists(links_path):
-            os.makedirs(links_path)
-        shell_link_path = os.path.join(links_path, 'libmojo_shell.so')
-        if os.path.lexists(shell_link_path):
-            os.unlink(shell_link_path)
-        os.symlink(self.paths.mojo_shell_path, shell_link_path)
-
-        logcat_cmd = ['adb', 'logcat']
-        logcat = subprocess.Popen(logcat_cmd, stdout=subprocess.PIPE)
-
-        mojo_cache_linker_path = os.path.join(
-            self.paths.sky_tools_directory, 'mojo_cache_linker.py')
-        cache_linker_cmd = [
-            mojo_cache_linker_path,
-            links_path,
-            self.pids['build_dir'],
-            'http://localhost:%s' % self.pids['remote_sky_server_port']
-        ]
-        return subprocess.Popen(cache_linker_cmd, stdin=logcat.stdout).pid
-
     def _pull_system_libraries(self, system_libs_root):
         # Pull down the system libraries this pid has already mapped in.
         # TODO(eseidel): This does not handle dynamic loads.
@@ -466,10 +440,14 @@ class SkyDebugger(object):
             '-type', 'd',
         ]).strip().split('\n')
 
-
     def gdb_attach_command(self, args):
         self.paths = self._create_paths_for_build_dir(self.pids['build_dir'])
 
+        # FIXME: The build system should keep this updated instead.
+        build_id_script_path = os.path.join(
+             self.paths.sky_tools_directory, 'update_build_id_tree.py')
+        subprocess.check_call([build_id_script_path, self.paths.build_dir])
+
         symbol_search_paths = [self.pids['build_dir']]
         gdb_path = '/usr/bin/gdb'
 
@@ -477,19 +455,16 @@ class SkyDebugger(object):
             'file %s' % self.paths.mojo_shell_path,
             'directory %s' % self.paths.src_root,
             'target remote localhost:%s' % GDB_PORT,
+            'set debug-file-directory %s' % self.paths.build_dir,
         ]
 
         # A bunch of extra work is needed for android:
         if 'remote_sky_server_port' in self.pids:
-            pid = self._start_mojo_cache_linker(CACHE_LINKS_PATH)
-            self.pids['mojo_cache_linker_pid'] = pid
-
             system_lib_dirs = self._pull_system_libraries(SYSTEM_LIBS_ROOT_PATH)
             init_commands.append(
                 'set solib-absolute-prefix %s' % SYSTEM_LIBS_ROOT_PATH)
 
             symbol_search_paths = system_lib_dirs + symbol_search_paths
-            symbol_search_paths.append(CACHE_LINKS_PATH)
 
             # TODO(eseidel): We need to look up the toolchain somehow?
             gdb_path = os.path.join(SRC_ROOT, 'third_party/android_tools/ndk/'