tools/gn/switches.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "tools/gn/switches.h"
   6
   7 namespace switches {
   8
   9 const char kArgs[] = "args";
  10 const char kArgs_HelpShort[] =
  11     "--args: Specifies build arguments overrides.";
  12 const char kArgs_Help[] =
  13     "--args: Specifies build arguments overrides.\n"
  14     "\n"
  15     "  See \"gn help buildargs\" for an overview of how build arguments work.\n"
  16     "\n"
  17     "  Most operations take a build directory. The build arguments are taken\n"
  18     "  from the previous build done in that directory. If a command specifies\n"
  19     "  --args, it will override the previous arguments stored in the build\n"
  20     "  directory, and use the specified ones.\n"
  21     "\n"
  22     "  The args specified will be saved to the build directory for subsequent\n"
  23     "  commands. Specifying --args=\"\" will clear all build arguments.\n"
  24     "\n"
  25     "Formatting\n"
  26     "\n"
  27     "  The value of the switch is interpreted in GN syntax. For typical usage\n"
  28     "  of string arguments, you will need to be careful about escaping of\n"
  29     "  quotes.\n"
  30     "\n"
  31     "Examples\n"
  32     "\n"
  33     "  gn gen out/Default --args=\"foo=\\\"bar\\\"\"\n"
  34     "\n"
  35     "  gn gen out/Default --args='foo=\"bar\" enable=true blah=7'\n"
  36     "\n"
  37     "  gn check out/Default --args=\"\"\n"
  38     "    Clears existing build args from the directory.\n"
  39     "\n"
  40     "  gn desc out/Default --args=\"some_list=[1, false, \\\"foo\\\"]\"\n";
  41
  42 #define COLOR_HELP_LONG \
  43     "--[no]color: Forces colored output on or off.\n"\
  44     "\n"\
  45     "  Normally GN will try to detect whether it is outputting to a terminal\n"\
  46     "  and will enable or disable color accordingly. Use of these switches\n"\
  47     "  will override the default.\n"\
  48     "\n"\
  49     "Examples\n"\
  50     "\n"\
  51     "  gn gen out/Default --color\n"\
  52     "\n"\
  53     "  gn gen out/Default --nocolor\n"
  54 const char kColor[] = "color";
  55 const char kColor_HelpShort[] =
  56     "--color: Force colored output.";
  57 const char kColor_Help[] = COLOR_HELP_LONG;
  58
  59 const char kDotfile[] = "dotfile";
  60 const char kDotfile_HelpShort[] =
  61     "--dotfile: Override the name of the \".gn\" file.";
  62 const char kDotfile_Help[] =
  63     "--dotfile: Override the name of the \".gn\" file.\n"
  64     "\n"
  65     "  Normally GN loads the \".gn\"file  from the source root for some basic\n"
  66     "  configuration (see \"gn help dotfile\"). This flag allows you to\n"
  67     "  use a different file.\n"
  68     "\n"
  69     "  Note that this interacts with \"--root\" in a possibly incorrect way.\n"
  70     "  It would be nice to test the edge cases and document or fix.\n";
  71
  72 const char kMarkdown[] = "markdown";
  73 const char kMarkdown_HelpShort[] =
  74     "--markdown: write the output in the Markdown format.";
  75 const char kMarkdown_Help[] =
  76     "--markdown: write the output in the Markdown format.\n";
  77
  78 const char kNoColor[] = "nocolor";
  79 const char kNoColor_HelpShort[] =
  80     "--nocolor: Force non-colored output.";
  81 const char kNoColor_Help[] = COLOR_HELP_LONG;
  82
  83 const char kQuiet[] = "q";
  84 const char kQuiet_HelpShort[] =
  85     "-q: Quiet mode. Don't print output on success.";
  86 const char kQuiet_Help[] =
  87     "-q: Quiet mode. Don't print output on success.\n"
  88     "\n"
  89     "  This is useful when running as a part of another script.\n";
  90
  91 const char kRoot[] = "root";
  92 const char kRoot_HelpShort[] =
  93     "--root: Explicitly specify source root.";
  94 const char kRoot_Help[] =
  95     "--root: Explicitly specify source root.\n"
  96     "\n"
  97     "  Normally GN will look up in the directory tree from the current\n"
  98     "  directory to find a \".gn\" file. The source root directory specifies\n"
  99     "  the meaning of \"//\" beginning with paths, and the BUILD.gn file\n"
 100     "  in that directory will be the first thing loaded.\n"
 101     "\n"
 102     "  Specifying --root allows GN to do builds in a specific directory\n"
 103     "  regardless of the current directory.\n"
 104     "\n"
 105     "Examples\n"
 106     "\n"
 107     "  gn gen //out/Default --root=/home/baracko/src\n"
 108     "\n"
 109     "  gn desc //out/Default --root=\"C:\\Users\\BObama\\My Documents\\foo\"\n";
 110
 111 const char kRuntimeDepsListFile[] = "runtime-deps-list-file";
 112 const char kRuntimeDepsListFile_HelpShort[] =
 113     "--runtime-deps-list-file: Save runtime dependencies for targets in file.";
 114 const char kRuntimeDepsListFile_Help[] =
 115     "--runtime-deps-list-file: Save runtime dependencies for targets in file.\n"
 116     "\n"
 117     "  --runtime-deps-list-file=<filename>\n"
 118     "\n"
 119     "  Where <filename> is a text file consisting of the labels, one per\n"
 120     "  line, of the targets for which runtime dependencies are desired.\n"
 121     "\n"
 122     "  See \"gn help runtime_deps\" for a description of how runtime\n"
 123     "  dependencies are computed.\n"
 124     "\n"
 125     "Runtime deps output file\n"
 126     "\n"
 127     "  For each target requested, GN will write a separate runtime dependency\n"
 128     "  file. The runtime dependency file will be in the output directory\n"
 129     "  alongside the output file of the target, with a \".runtime_deps\"\n"
 130     "  extension. For example, if the target \"//foo:bar\" is listed in the\n"
 131     "  input file, and that target produces an output file \"bar.so\", GN\n"
 132     "  will create a file \"bar.so.runtime_deps\" in the build directory.\n"
 133     "\n"
 134     "  If a source set, action, copy, or group is listed, the runtime deps\n"
 135     "  file will correspond to the .stamp file corresponding to that target.\n"
 136     "  This is probably not useful; the use-case for this feature is\n"
 137     "  generally executable targets.\n"
 138     "\n"
 139     "  The runtime dependency file will list one file per line, with no\n"
 140     "  escaping. The files will be relative to the root_build_dir. The first\n"
 141     "  line of the file will be the main output file of the target itself\n"
 142     "  (in the above example, \"bar.so\").\n";
 143
 144 const char kThreads[] = "threads";
 145 const char kThreads_HelpShort[] =
 146     "--threads: Specify number of worker threads.";
 147 const char kThreads_Help[] =
 148     "--threads: Specify number of worker threads.\n"
 149     "\n"
 150     "  GN runs many threads to load and run build files. This can make\n"
 151     "  debugging challenging. Or you may want to experiment with different\n"
 152     "  values to see how it affects performance.\n"
 153     "\n"
 154     "  The parameter is the number of worker threads. This does not count the\n"
 155     "  main thread (so there are always at least two).\n"
 156     "\n"
 157     "Examples\n"
 158     "\n"
 159     "  gen gen out/Default --threads=1\n";
 160
 161 const char kTime[] = "time";
 162 const char kTime_HelpShort[] =
 163     "--time: Outputs a summary of how long everything took.";
 164 const char kTime_Help[] =
 165     "--time: Outputs a summary of how long everything took.\n"
 166     "\n"
 167     "  Hopefully self-explanatory.\n"
 168     "\n"
 169     "Examples\n"
 170     "\n"
 171     "  gn gen out/Default --time\n";
 172
 173 const char kTracelog[] = "tracelog";
 174 const char kTracelog_HelpShort[] =
 175     "--tracelog: Writes a Chrome-compatible trace log to the given file.";
 176 const char kTracelog_Help[] =
 177     "--tracelog: Writes a Chrome-compatible trace log to the given file.\n"
 178     "\n"
 179     "  The trace log will show file loads, executions, scripts, and writes.\n"
 180     "  This allows performance analysis of the generation step.\n"
 181     "\n"
 182     "  To view the trace, open Chrome and navigate to \"chrome://tracing/\",\n"
 183     "  then press \"Load\" and specify the file you passed to this parameter.\n"
 184     "\n"
 185     "Examples\n"
 186     "\n"
 187     "  gn gen out/Default --tracelog=mytrace.trace\n";
 188
 189 const char kVerbose[] = "v";
 190 const char kVerbose_HelpShort[] =
 191     "-v: Verbose logging.";
 192 const char kVerbose_Help[] =
 193     "-v: Verbose logging.\n"
 194     "\n"
 195     "  This will spew logging events to the console for debugging issues.\n"
 196     "  Good luck!\n";
 197
 198 const char kVersion[] = "version";
 199 const char kVersion_HelpShort[] =
 200     "--version: Prints the GN version number and exits.";
 201 // It's impossible to see this since gn_main prints the version and exits
 202 // immediately if this switch is used.
 203 const char kVersion_Help[] = "";
 204
 205 // -----------------------------------------------------------------------------
 206
 207 SwitchInfo::SwitchInfo()
 208     : short_help(""),
 209       long_help("") {
 210 }
 211
 212 SwitchInfo::SwitchInfo(const char* short_help, const char* long_help)
 213     : short_help(short_help),
 214       long_help(long_help) {
 215 }
 216
 217 #define INSERT_VARIABLE(var) \
 218     info_map[k##var] = SwitchInfo(k##var##_HelpShort, k##var##_Help);
 219
 220 const SwitchInfoMap& GetSwitches() {
 221   static SwitchInfoMap info_map;
 222   if (info_map.empty()) {
 223     INSERT_VARIABLE(Args)
 224     INSERT_VARIABLE(Color)
 225     INSERT_VARIABLE(Dotfile)
 226     INSERT_VARIABLE(Markdown)
 227     INSERT_VARIABLE(NoColor)
 228     INSERT_VARIABLE(Root)
 229     INSERT_VARIABLE(Quiet)
 230     INSERT_VARIABLE(RuntimeDepsListFile)
 231     INSERT_VARIABLE(Time)
 232     INSERT_VARIABLE(Tracelog)
 233     INSERT_VARIABLE(Verbose)
 234     INSERT_VARIABLE(Version)
 235   }
 236   return info_map;
 237 }
 238
 239 #undef INSERT_VARIABLE
 240
 241 }  // namespace switches