ios/build/packaging/link_dependencies.py

   1 #!/usr/bin/env python
   2 #
   3 # Copyright 2014 The Chromium Authors. All rights reserved.
   4 # Use of this source code is governed by a BSD-style license that can be
   5 # found in the LICENSE file.
   6
   7 """Links the deps of a binary into a static library.
   8
   9 Run with a working directory, the name of a binary target, and the name of the
  10 static library that should be produced. For example:
  11
  12   $ link_dependencies.py out/Release-iphoneos \
  13                          crnet_consumer.app/crnet_consumer \
  14                          out/Release-iphoneos/crnet_standalone.a
  15 """
  16
  17 import argparse
  18 import os
  19 import subprocess
  20
  21
  22 class SubprocessError(Exception):
  23   pass
  24
  25
  26 def extract_inputs(query_result, prefix=''):
  27   """Extracts inputs from ninja query output.
  28
  29   Given 'ninja -t query' output for a target, extracts all the inputs of that
  30   target, prefixing them with an optional prefix. Inputs prefixed with '|' are
  31   implicit, so we discard them as they shouldn't be linked into the resulting
  32   binary (these are things like the .ninja files themselves, dep lists, and so
  33   on).
  34
  35   Example query result:
  36     arch/crnet_consumer.armv7:
  37       input: link
  38         obj/[long path...]/crnet_consumer.crnet_consumer_app_delegate.armv7.o
  39         obj/[long path...]/crnet_consumer.crnet_consumer_view_controller.armv7.o
  40         obj/[long path...]/crnet_consumer.main.armv7.o
  41         libcrnet.a
  42         libdata_reduction_proxy_code_browser.a
  43         ... many more inputs ...
  44         liburl_util.a
  45         | obj/content/content.actions_depends.stamp
  46         | gen/components/data_reduction_proxy/common/version.h
  47         | obj/ui/resources/ui_resources.actions_rules_copies.stamp
  48         ... more implicit inputs ...
  49     outputs:
  50       crnet_consumer.app/crnet_consumer
  51
  52   Args:
  53     query_result: output from 'ninja -t query'
  54     prefix: optional file system path to prefix to returned inputs
  55
  56   Returns:
  57     A list of the inputs.
  58   """
  59   extracting = False
  60   inputs = []
  61   for line in query_result.splitlines():
  62     if line.startswith('  input:'):
  63       extracting = True
  64     elif line.startswith('  outputs:'):
  65       extracting = False
  66     elif extracting and '|' not in line:
  67       inputs.append(os.path.join(prefix, line.strip()))
  68   return inputs
  69
  70
  71 def query_ninja(target, workdir, prefix=''):
  72   """Returns the inputs for the named target.
  73
  74   Queries ninja for the set of inputs of the named target, then returns the list
  75   of inputs to that target.
  76
  77   Args:
  78     target: ninja target name to query for
  79     workdir: workdir for ninja
  80     prefix: optional file system path to prefix to returned inputs
  81
  82   Returns:
  83     A list of file system paths to the inputs to the named target.
  84   """
  85   proc = subprocess.Popen(['ninja', '-C', workdir, '-t', 'query', target],
  86                           stdout=subprocess.PIPE)
  87   stdout, _ = proc.communicate()
  88   return extract_inputs(stdout, prefix)
  89
  90
  91 def is_library(target):
  92   """Returns whether target is a library file."""
  93   return os.path.splitext(target)[1] in ('.a', '.o')
  94
  95
  96 def library_deps(targets, workdir, query=query_ninja):
  97   """Returns the set of library dependencies for the supplied targets.
  98
  99   The entries in the targets list can be either a static library, an object
 100   file, or an executable. Static libraries and object files are incorporated
 101   directly; executables are treated as being thin executable inputs to a fat
 102   executable link step, and have their own library dependencies added in their
 103   place.
 104
 105   Args:
 106     targets: list of targets to include library dependencies from
 107     workdir: working directory to run ninja queries in
 108     query: function taking target, workdir, and prefix and returning an input
 109            set
 110   Returns:
 111     Set of library dependencies.
 112   """
 113   deps = set()
 114   for target in targets:
 115     if is_library(target):
 116       deps.add(os.path.join(workdir, target))
 117     else:
 118       deps = deps.union(query(target, workdir, workdir))
 119   return deps
 120
 121
 122 def link(output, inputs):
 123   """Links output from inputs using libtool.
 124
 125   Args:
 126     output: file system path to desired output library
 127     inputs: list of file system paths to input libraries
 128   """
 129   p = subprocess.Popen(['libtool', '-o', output] + inputs)
 130   p.communicate()
 131   if p.returncode != 0:
 132     message = "subprocess libtool returned {0}".format(p.returncode)
 133     raise SubprocessError(message)
 134
 135
 136 def main():
 137   parser = argparse.ArgumentParser(
 138       description='Link dependencies of a ninja target into a static library')
 139   parser.add_argument('workdir', nargs=1, help='ninja working directory')
 140   parser.add_argument('target', nargs=1, help='target to query for deps')
 141   parser.add_argument('output', nargs=1, help='path to output static library')
 142   args = parser.parse_args()
 143
 144   inputs = query_ninja(args.target[0], args.workdir[0])
 145   link(args.output[0], list(library_deps(inputs, args.workdir[0])))
 146
 147
 148 if __name__ == '__main__':
 149   main()