| # Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| # Autocompletion config for YouCompleteMe in Chromium. |
| # |
| # USAGE: |
| # |
| # 1. Install YCM [https://github.com/Valloric/YouCompleteMe] |
| # (Googlers should check out [go/ycm]) |
| # |
| # 2. Create a symbolic link to this file called .ycm_extra_conf.py in the |
| # directory above your Chromium checkout (i.e. next to your .gclient file). |
| # |
| # cd src |
| # ln -rs tools/vim/chromium.ycm_extra_conf.py ../.ycm_extra_conf.py |
| # |
| # 3. (optional) Whitelist the .ycm_extra_conf.py from step #2 by adding the |
| # following to your .vimrc: |
| # |
| # let g:ycm_extra_conf_globlist=['<path to .ycm_extra_conf.py>'] |
| # |
| # You can also add other .ycm_extra_conf.py files you want to use to this |
| # list to prevent excessive prompting each time you visit a directory |
| # covered by a config file. |
| # |
| # 4. Profit |
| # |
| # |
| # Usage notes: |
| # |
| # * You must use ninja & clang to build Chromium. |
| # |
| # * You must have run gyp_chromium and built Chromium recently. |
| # |
| # |
| # Hacking notes: |
| # |
| # * The purpose of this script is to construct an accurate enough command line |
| # for YCM to pass to clang so it can build and extract the symbols. |
| # |
| # * Right now, we only pull the -I and -D flags. That seems to be sufficient |
| # for everything I've used it for. |
| # |
| # * That whole ninja & clang thing? We could support other configs if someone |
| # were willing to write the correct commands and a parser. |
| # |
| # * This has only been tested on gPrecise. |
| |
| |
| import os |
| import os.path |
| import re |
| import shlex |
| import subprocess |
| import sys |
| |
| # A dictionary mapping Clang binary path to a list of Clang command line |
| # arguments that specify the system include paths. It is used as a cache of the |
| # system include options since these options aren't expected to change per |
| # source file for the same clang binary. SystemIncludeDirectoryFlags() updates |
| # this map each time it runs a Clang binary to determine system include paths. |
| # |
| # Entries look like: |
| # '/home/username/my-llvm/bin/clang++': ['-isystem', |
| # '/home/username/my-llvm/include', '-isystem', '/usr/include'] |
| _clang_system_include_map = {} |
| |
| |
| # Flags from YCM's default config. |
| _default_flags = [ |
| '-DUSE_CLANG_COMPLETER', |
| '-std=c++11', |
| '-x', |
| 'c++', |
| ] |
| |
| |
| def FallbackSystemIncludeDirectoryFlags(): |
| """Returns a best guess list of system include directory flags for Clang. |
| |
| If Ninja doesn't give us a build step that specifies a Clang invocation or if |
| something goes wrong while determining the system include paths, then this |
| function can be used to determine some set of values that's better than |
| nothing. |
| |
| Returns: |
| (List of Strings) Compiler flags that specify the system include paths. |
| """ |
| if _clang_system_include_map: |
| return _clang_system_include_map.itervalues().next() |
| return [] |
| |
| |
| def SystemIncludeDirectoryFlags(clang_binary, clang_flags): |
| """Determines compile flags for specifying system include directories. |
| |
| Use as a workaround for https://github.com/Valloric/YouCompleteMe/issues/303 |
| |
| Caches the results of determining the system include directories in |
| _clang_system_include_map. Subsequent calls to SystemIncludeDirectoryFlags() |
| uses the cached results for the same binary even if |clang_flags| differ. |
| |
| Args: |
| clang_binary: (String) Path to clang binary. |
| clang_flags: (List of Strings) List of additional flags to clang. It may |
| affect the choice of system include directories if -stdlib= is specified. |
| _default_flags are always included in the list of flags passed to clang. |
| |
| Returns: |
| (List of Strings) Compile flags to append. |
| """ |
| |
| if clang_binary in _clang_system_include_map: |
| return _clang_system_include_map[clang_binary] |
| |
| all_clang_flags = [] + _default_flags |
| all_clang_flags += [flag for flag in clang_flags |
| if flag.startswith('-std=') or flag.startswith('-stdlib=')] |
| all_clang_flags += ['-v', '-E', '-'] |
| try: |
| with open(os.devnull, 'rb') as DEVNULL: |
| output = subprocess.check_output([clang_binary] + all_clang_flags, |
| stdin=DEVNULL, stderr=subprocess.STDOUT) |
| except: |
| # Even though we couldn't figure out the flags for the given binary, if we |
| # have results from another one, we'll use that. This logic assumes that the |
| # list of default system directories for one binary can be used with |
| # another. |
| return FallbackSystemIncludeDirectoryFlags() |
| includes_regex = r'#include <\.\.\.> search starts here:\s*' \ |
| r'(.*?)End of search list\.' |
| includes = re.search(includes_regex, output.decode(), re.DOTALL).group(1) |
| system_include_flags = [] |
| for path in includes.splitlines(): |
| path = path.strip() |
| if os.path.isdir(path): |
| system_include_flags.append('-isystem') |
| system_include_flags.append(path) |
| if system_include_flags: |
| _clang_system_include_map[clang_binary] = system_include_flags |
| return system_include_flags |
| |
| |
| def PathExists(*args): |
| return os.path.exists(os.path.join(*args)) |
| |
| |
| def FindChromeSrcFromFilename(filename): |
| """Searches for the root of the Chromium checkout. |
| |
| Simply checks parent directories until it finds .gclient and src/. |
| |
| Args: |
| filename: (String) Path to source file being edited. |
| |
| Returns: |
| (String) Path of 'src/', or None if unable to find. |
| """ |
| curdir = os.path.normpath(os.path.dirname(filename)) |
| while not (os.path.basename(os.path.realpath(curdir)) == 'src' |
| and PathExists(curdir, 'DEPS') |
| and (PathExists(curdir, '..', '.gclient') |
| or PathExists(curdir, '.git'))): |
| nextdir = os.path.normpath(os.path.join(curdir, '..')) |
| if nextdir == curdir: |
| return None |
| curdir = nextdir |
| return curdir |
| |
| |
| def GetDefaultCppFile(chrome_root, filename): |
| """Returns the default target file to use for |filename|. |
| |
| The default target is some source file that is known to exist and loosely |
| related to |filename|. Compile flags used to build the default target is |
| assumed to be a close-enough approximation for building |filename|. |
| |
| Args: |
| chrome_root: (String) Absolute path to the root of Chromium checkout. |
| filename: (String) Absolute path to the target source file. |
| |
| Returns: |
| (String) Absolute path to substitute target file. |
| """ |
| blink_root = os.path.join(chrome_root, 'third_party', 'WebKit') |
| if filename.startswith(blink_root): |
| return os.path.join(blink_root, 'Source', 'core', 'Init.cpp') |
| else: |
| return os.path.join(chrome_root, 'base', 'logging.cc') |
| |
| |
| def GetBuildTargetForSourceFile(chrome_root, filename): |
| """Returns a build target corresponding to |filename|. |
| |
| Args: |
| chrome_root: (String) Absolute path to the root of Chromium checkout. |
| filename: (String) Absolute path to the target source file. |
| |
| Returns: |
| (String) Absolute path to build target. |
| """ |
| if filename.endswith('.h'): |
| # Header files can't be built. Instead, try to match a header file to its |
| # corresponding source file. |
| alternates = ['.cc', '.cpp', '.c'] |
| for alt_extension in alternates: |
| alt_name = filename[:-2] + alt_extension |
| if os.path.exists(alt_name): |
| return alt_name |
| |
| # Failing that, build a default file instead and assume that the resulting |
| # commandline options are valid for the .h file. |
| return GetDefaultCppFile(chrome_root, filename) |
| |
| return filename |
| |
| |
| def GetClangCommandLineFromNinjaForFilename(out_dir, filename): |
| """Returns the Clang command line for building |filename| |
| |
| Asks ninja for the list of commands used to build |filename| and returns the |
| final Clang invocation. |
| |
| Args: |
| out_dir: (String) Absolute path to ninja build output directory. |
| filename: (String) Absolute path to source file. |
| |
| Returns: |
| (String) Clang command line or None if command line couldn't be determined. |
| """ |
| # Ninja needs the path to the source file relative to the output build |
| # directory. |
| rel_filename = os.path.relpath(os.path.realpath(filename), out_dir) |
| |
| # Ask ninja how it would build our source file. |
| p = subprocess.Popen(['ninja', '-v', '-C', out_dir, '-t', |
| 'commands', rel_filename + '^'], |
| stdout=subprocess.PIPE) |
| stdout, stderr = p.communicate() |
| if p.returncode: |
| return None |
| |
| # Ninja might execute several commands to build something. We want the last |
| # clang command. |
| for line in reversed(stdout.split('\n')): |
| if 'clang' in line: |
| return line |
| return None |
| |
| |
| def GetNormalizedClangCommand(command, out_dir): |
| """Gets the normalized Clang binary path if |command| is a Clang command. |
| |
| Args: |
| command: (String) Clang command. |
| out_dir: (String) Absolute path the ninja build directory. |
| |
| Returns: |
| (String or None) |
| None : if command is not a clang command. |
| Absolute path to clang binary : if |command| is an absolute or relative |
| path to clang. If relative, it is assumed to be relative to |out_dir|. |
| |command|: if command is a name of a binary. |
| """ |
| if command.endswith('clang++') or command.endswith('clang'): |
| if os.path.basename(command) == command: |
| return command |
| return os.path.normpath(os.path.join(out_dir, command)) |
| return None |
| |
| |
| def GetClangOptionsFromCommandLine(clang_commandline, out_dir, |
| additional_flags): |
| """Extracts relevant command line options from |clang_commandline| |
| |
| Args: |
| clang_commandline: (String) Full Clang invocation. |
| out_dir: (String) Absolute path to ninja build directory. Relative paths in |
| the command line are relative to |out_dir|. |
| additional_flags: (List of String) Additional flags to return. |
| |
| Returns: |
| ((List of Strings), (List of Strings)) The first item in the tuple is a list |
| of command line flags for this source file. The second item in the tuple is |
| a list of command line flags that define the system include paths. Either or |
| both can be empty. |
| """ |
| chrome_flags = [] + additional_flags |
| system_include_flags = [] |
| |
| # Parse flags that are important for YCM's purposes. |
| clang_tokens = shlex.split(clang_commandline) |
| for flag in clang_tokens: |
| if flag.startswith('-I'): |
| # Relative paths need to be resolved, because they're relative to the |
| # output dir, not the source. |
| if flag[2] == '/': |
| chrome_flags.append(flag) |
| else: |
| abs_path = os.path.normpath(os.path.join(out_dir, flag[2:])) |
| chrome_flags.append('-I' + abs_path) |
| elif flag.startswith('-std'): |
| chrome_flags.append(flag) |
| elif flag.startswith('-') and flag[1] in 'DWFfmO': |
| if flag == '-Wno-deprecated-register' or flag == '-Wno-header-guard': |
| # These flags causes libclang (3.3) to crash. Remove it until things |
| # are fixed. |
| continue |
| chrome_flags.append(flag) |
| |
| # Assume that the command for invoking clang++ looks like one of the |
| # following: |
| # 1) /path/to/clang/clang++ arguments |
| # 2) /some/wrapper /path/to/clang++ arguments |
| # |
| # We'll look at the first two tokens on the command line to see if they look |
| # like Clang commands, and if so use it to determine the system include |
| # directory flags. |
| for command in clang_tokens[0:2]: |
| normalized_command = GetNormalizedClangCommand(command, out_dir) |
| if normalized_command: |
| system_include_flags += SystemIncludeDirectoryFlags(normalized_command, |
| chrome_flags) |
| break |
| |
| return (chrome_flags, system_include_flags) |
| |
| |
| def GetClangOptionsFromNinjaForFilename(chrome_root, filename): |
| """Returns the Clang command line options needed for building |filename|. |
| |
| Command line options are based on the command used by ninja for building |
| |filename|. If |filename| is a .h file, uses its companion .cc or .cpp file. |
| If a suitable companion file can't be located or if ninja doesn't know about |
| |filename|, then uses default source files in Blink and Chromium for |
| determining the commandline. |
| |
| Args: |
| chrome_root: (String) Path to src/. |
| filename: (String) Absolute path to source file being edited. |
| |
| Returns: |
| ((List of Strings), (List of Strings)) The first item in the tuple is a list |
| of command line flags for this source file. The second item in the tuple is |
| a list of command line flags that define the system include paths. Either or |
| both can be empty. |
| """ |
| if not chrome_root: |
| return ([],[]) |
| |
| # Generally, everyone benefits from including Chromium's src/, because all of |
| # Chromium's includes are relative to that. |
| additional_flags = ['-I' + os.path.join(chrome_root)] |
| |
| # Version of Clang used to compile Chromium can be newer then version of |
| # libclang that YCM uses for completion. So it's possible that YCM's libclang |
| # doesn't know about some used warning options, which causes compilation |
| # warnings (and errors, because of '-Werror'); |
| additional_flags.append('-Wno-unknown-warning-option') |
| |
| sys.path.append(os.path.join(chrome_root, 'tools', 'vim')) |
| from ninja_output import GetNinjaOutputDirectory |
| out_dir = os.path.realpath(GetNinjaOutputDirectory(chrome_root)) |
| |
| clang_line = GetClangCommandLineFromNinjaForFilename( |
| out_dir, GetBuildTargetForSourceFile(chrome_root, filename)) |
| if not clang_line: |
| # If ninja didn't know about filename or it's companion files, then try a |
| # default build target. It is possible that the file is new, or build.ninja |
| # is stale. |
| clang_line = GetClangCommandLineFromNinjaForFilename( |
| out_dir, GetDefaultCppFile(chrome_root, filename)) |
| |
| return GetClangOptionsFromCommandLine(clang_line, out_dir, additional_flags) |
| |
| |
| def FlagsForFile(filename): |
| """This is the main entry point for YCM. Its interface is fixed. |
| |
| Args: |
| filename: (String) Path to source file being edited. |
| |
| Returns: |
| (Dictionary) |
| 'flags': (List of Strings) Command line flags. |
| 'do_cache': (Boolean) True if the result should be cached. |
| """ |
| abs_filename = os.path.abspath(filename) |
| chrome_root = FindChromeSrcFromFilename(abs_filename) |
| (chrome_flags, system_include_flags) = GetClangOptionsFromNinjaForFilename( |
| chrome_root, abs_filename) |
| |
| # If either chrome_flags or system_include_flags could not be determined, then |
| # assume that was due to a transient failure. Preventing YCM from caching the |
| # flags allows us to try to determine the flags again. |
| should_cache_flags_for_file = \ |
| bool(chrome_flags) and bool(system_include_flags) |
| |
| if not system_include_flags: |
| system_include_flags = FallbackSystemIncludeDirectoryFlags() |
| final_flags = _default_flags + chrome_flags + system_include_flags |
| |
| return { |
| 'flags': final_flags, |
| 'do_cache': should_cache_flags_for_file |
| } |