ninja: Survive case-only file renames on case-insensitive filesystems.

pylib/gyp/generator/ninja.py

 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import copy
 import hashlib
 import os.path
 import re
 import subprocess
 import sys
@@ skipping 336 matching lines @@
 
     assert targets == filter(None, targets), targets
     if len(targets) == 0:
       return None
     if len(targets) > 1:
       stamp = self.GypPathToUniqueOutput(name + '.stamp')
       targets = self.ninja.build(stamp, 'stamp', targets)
       self.ninja.newline()
     return targets[0]
 
-  def WriteSpec(self, spec, config_name, generator_flags):
+  def WriteSpec(self, spec, config_name, generator_flags,
+      case_sensitive_filesystem):

[M-A Ruel, 2012/09/10 14:03:13]

Sorry I'm not familiar with the code so the question may seem odd: should
case_sensitive be a property of self?

     """The main entry point for NinjaWriter: write the build rules for a spec.
 
     Returns a Target object, which represents the output paths for this spec.
     Returns None if there are no outputs (e.g. a settings-only 'none' type
     target)."""
 
     self.config_name = config_name
     self.name = spec['target_name']
     self.toolset = spec['toolset']
     config = spec['configurations'][config_name]
@@ skipping 53 matching lines @@
     if sources:
       pch = None
       if self.flavor == 'win':
         pch = gyp.msvs_emulation.PrecompiledHeader(
             self.msvs_settings, config_name, self.GypPathToNinja)
       else:
         pch = gyp.xcode_emulation.MacPrefixHeader(
             self.xcode_settings, self.GypPathToNinja,
             lambda path, lang: self.GypPathToUniqueOutput(path + '-' + lang))
       link_deps = self.WriteSources(
-          config_name, config, sources, compile_depends_stamp, pch)
+          config_name, config, sources, compile_depends_stamp, pch,
+          case_sensitive_filesystem)
       # Some actions/rules output 'sources' that are already object files.
       link_deps += [self.GypPathToNinja(f)
           for f in sources if f.endswith(self.obj_ext)]
 
     if self.flavor == 'win' and self.target.type == 'static_library':
       self.target.component_objs = link_deps
 
     # Write out a link step, if needed.
     output = None
     if link_deps or self.target.actions_stamp or actions_depends:
@@ skipping 256 matching lines @@
 
     env = self.GetSortedXcodeEnv(additional_settings=extra_env)
     env = self.ComputeExportEnvString(env)
 
     self.ninja.build(out, 'mac_tool', info_plist,
                      variables=[('mactool_cmd', 'copy-info-plist'),
                                 ('env', env)])
     bundle_depends.append(out)
 
   def WriteSources(self, config_name, config, sources, predepends,
-                   precompiled_header):
+                   precompiled_header, case_sensitive_filesystem):
     """Write build rules to compile all of |sources|."""
     if self.toolset == 'host':
       self.ninja.variable('ar', '$ar_host')
       self.ninja.variable('cc', '$cc_host')
       self.ninja.variable('cxx', '$cxx_host')
       self.ninja.variable('ld', '$ld_host')
 
     extra_defines = []
     if self.flavor == 'mac':
       cflags = self.xcode_settings.GetCflags(config_name)
@@ skipping 72 matching lines @@
       elif self.flavor == 'mac' and ext == 'mm':
         command = 'objcxx'
       elif self.flavor == 'win' and ext == 'rc':
         command = 'rc'
         obj_ext = '.res'
       else:
         # Ignore unhandled extensions.
         continue
       input = self.GypPathToNinja(source)
       output = self.GypPathToUniqueOutput(filename + obj_ext)
+      # Ninja's depfile handling gets confused when the case of a filename
+      # changes on a case-insensitive file system. To work around that, always
+      # convert .o filenames to lowercase on such file systems. See
+      # https://github.com/martine/ninja/issues/402 for details.
+      if not case_sensitive_filesystem:
+        output = output.lower()
       implicit = precompiled_header.GetObjDependencies([input], [output])
       self.ninja.build(output, command, input,
                        implicit=[gch for _, _, gch in implicit],
                        order_only=predepends)
       outputs.append(output)
 
     self.WritePchTargets(pch_commands)
 
     self.ninja.newline()
     return outputs
@@ skipping 478 matching lines @@
   # build_dir: relative path from source root to our output files.
   # e.g. "out/Debug"
   build_dir = os.path.join(generator_flags.get('output_dir', 'out'),
                            config_name)
 
   toplevel_build = os.path.join(options.toplevel_dir, build_dir)
 
   master_ninja = ninja_syntax.Writer(
       OpenOutput(os.path.join(toplevel_build, 'build.ninja')),
       width=120)
+  case_sensitive_filesystem = not os.path.exists(
+      os.path.join(toplevel_build, 'BUILD.NINJA'))

[M-A Ruel, 2012/09/10 14:03:13]

<3 that's a good idea.

 
   # Put build-time support tools in out/{config_name}.
   gyp.common.CopyTool(flavor, toplevel_build)
 
   # Grab make settings for CC/CXX.
   # The rules are
   # - The priority from low to high is gcc/g++, the 'make_global_settings' in
   #   gyp, the environment variable.
   # - If there is no 'make_global_settings' for CC.host/CXX.host or
   #   'CC_host'/'CXX_host' enviroment variable, cc_host/cxx_host should be set
@@ skipping 366 matching lines @@
     if toolset != 'target':
       obj += '.' + toolset
     output_file = os.path.join(obj, base_path, name + '.ninja')
 
     abs_build_dir = os.path.abspath(toplevel_build)
     writer = NinjaWriter(qualified_target, target_outputs, base_path, build_dir,
                          OpenOutput(os.path.join(toplevel_build, output_file)),
                          flavor, abs_build_dir=abs_build_dir)
     master_ninja.subninja(output_file)
 
-    target = writer.WriteSpec(spec, config_name, generator_flags)
+    target = writer.WriteSpec(
+        spec, config_name, generator_flags, case_sensitive_filesystem)
     if target:
       if name != target.FinalOutput() and spec['toolset'] == 'target':
         target_short_names.setdefault(name, []).append(target)
       target_outputs[qualified_target] = target
       if qualified_target in all_targets:
         all_outputs.add(target.FinalOutput())
 
   if target_short_names:
     # Write a short name to build this target.  This benefits both the
     # "build chrome" case as well as the gyp tests, which expect to be
@@ skipping 16 matching lines @@
 
   user_config = params.get('generator_flags', {}).get('config', None)
   if user_config:
     GenerateOutputForConfig(target_list, target_dicts, data, params,
                             user_config)
   else:
     config_names = target_dicts[target_list[0]]['configurations'].keys()
     for config_name in config_names:
       GenerateOutputForConfig(target_list, target_dicts, data, params,
                               config_name)