Include a pak file in the binary_size output if requested.

tools/binary_size/run_binary_size_analysis.py

Index: tools/binary_size/run_binary_size_analysis.py
diff --git a/tools/binary_size/run_binary_size_analysis.py b/tools/binary_size/run_binary_size_analysis.py
index f2c95b104fe042b38901da1732d22c39de4565a4..23869e0f64cbdfe659eebd310633d990e0cc96c9 100755
--- a/tools/binary_size/run_binary_size_analysis.py
+++ b/tools/binary_size/run_binary_size_analysis.py
@@ -18,6 +18,7 @@ import optparse
 import os
 import re
 import shutil
+import struct
 import subprocess
 import sys
 import tempfile
@@ -654,6 +655,72 @@ def GetNmSymbols(nm_infile, outfile, library, jobs, verbose,
     return list(binary_size_utils.ParseNm(infile))
 
 
+PAK_RESOURCE_ID_TO_STRING = { "inited": False }
+
+def LoadPakIdsFromResourceFile(filename):
+  """Given a file name, it loads everything that looks like a resource id
+  into PAK_RESOURCE_ID_TO_STRING."""
+  with open(filename) as resource_header:
+    for line in resource_header:
+      if line.startswith("#define "):
+        line_data = line.split()
+        if len(line_data) == 3:
+          try:
+            resource_number = int(line_data[2])
+            resource_name = line_data[1]
+            PAK_RESOURCE_ID_TO_STRING[resource_number] = resource_name
+          except ValueError:
+            pass
+
+def GetReadablePakResourceName(pak_file, resource_id):
+  """Pak resources have a numeric identifier. It is not helpful when
+  trying to locate where footprint is generated. This does its best to
+  map the number to a usable string."""
+  if not PAK_RESOURCE_ID_TO_STRING['inited']:
+    # Try to find resource header files generated by grit when
+    # building the pak file. We'll look for files named *resources.h"
+    # and lines of the type:
+    #    #define MY_RESOURCE_JS 1234
+    PAK_RESOURCE_ID_TO_STRING['inited'] = True
+    gen_dir = os.path.join(os.path.dirname(pak_file), 'gen')
+    if os.path.isdir(gen_dir):
+      for dirname, _dirs, files in os.walk(gen_dir):
+        for filename in files:
+          if filename.endswith('resources.h'):
+            LoadPakIdsFromResourceFile(os.path.join(dirname, filename))
+  return PAK_RESOURCE_ID_TO_STRING.get(resource_id,
+                                       'Pak Resource %d' % resource_id)
+
+def AddPakData(symbols, pak_file):
+  """Adds pseudo-symbols from a pak file."""
+  pak_file = os.path.abspath(pak_file)
+  with open(pak_file, 'rb') as pak:
+    data = pak.read()
+
+  PAK_FILE_VERSION = 4
+  HEADER_LENGTH = 2 * 4 + 1  # Two uint32s. (file version, number of entries)
+                             # and one uint8 (encoding of text resources)
+  INDEX_ENTRY_SIZE = 2 + 4  # Each entry is a uint16 and a uint32.
+  version, num_entries, _encoding = struct.unpack('<IIB', data[:HEADER_LENGTH])
+  assert version == PAK_FILE_VERSION, ('Unsupported pak file '
+                                       'version (%d) in %s. Only '
+                                       'support version %d' %
+                                       (version, pak_file, PAK_FILE_VERSION))
+  if num_entries > 0:
+    # Read the index and data.
+    data = data[HEADER_LENGTH:]
+    for _ in range(num_entries):
+      resource_id, offset = struct.unpack('<HI', data[:INDEX_ENTRY_SIZE])
+      data = data[INDEX_ENTRY_SIZE:]
+      _next_id, next_offset = struct.unpack('<HI', data[:INDEX_ENTRY_SIZE])
+      resource_size = next_offset - offset
+
+      symbol_name = GetReadablePakResourceName(pak_file, resource_id)
+      symbol_path = pak_file
+      symbol_type = 'd' # Data. Approximation.
+      symbol_size = resource_size
+      symbols.append((symbol_name, symbol_type, symbol_size, symbol_path))
+
 def _find_in_system_path(binary):
   """Locate the full path to binary in the system path or return None
   if not found."""
@@ -726,6 +793,9 @@ def main():
   parser.add_option('--library', metavar='PATH',
                     help='if specified, process symbols in the library at '
                     'the specified path. Mutually exclusive with --nm-in.')
+  parser.add_option('--pak', metavar='PATH',
+                    help='if specified, includes the contents of the '
+                    'specified *.pak file in the output.')
   parser.add_option('--nm-binary',
                     help='use the specified nm binary to analyze library. '
                     'This is to be used when the nm in the path is not for '
@@ -796,6 +866,9 @@ def main():
     assert nm_binary, 'Unable to find nm in the path. Use --nm-binary '\
         'to specify location.'
 
+  if opts.pak:
+    assert os.path.isfile(opts.pak), 'Could not find ' % opts.pak
+
   print('addr2line: %s' % addr2line_binary)
   print('nm: %s' % nm_binary)
 
@@ -806,6 +879,10 @@ def main():
                          addr2line_binary, nm_binary,
                          opts.disable_disambiguation is None,
                          opts.source_path)
+
+  if opts.pak:
+    AddPakData(symbols, opts.pak)
+
   if not os.path.exists(opts.destdir):
     os.makedirs(opts.destdir, 0755)