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 kNoColor[] = "nocolor";
  73 const char kNoColor_HelpShort[] =
  74     "--nocolor: Force non-colored output.";
  75 const char kNoColor_Help[] = COLOR_HELP_LONG;
  76
  77 const char kQuiet[] = "q";
  78 const char kQuiet_HelpShort[] =
  79     "-q: Quiet mode. Don't print output on success.";
  80 const char kQuiet_Help[] =
  81     "-q: Quiet mode. Don't print output on success.\n"
  82     "\n"
  83     "  This is useful when running as a part of another script.\n";
  84
  85 const char kRoot[] = "root";
  86 const char kRoot_HelpShort[] =
  87     "--root: Explicitly specify source root.";
  88 const char kRoot_Help[] =
  89     "--root: Explicitly specify source root.\n"
  90     "\n"
  91     "  Normally GN will look up in the directory tree from the current\n"
  92     "  directory to find a \".gn\" file. The source root directory specifies\n"
  93     "  the meaning of \"//\" beginning with paths, and the BUILD.gn file\n"
  94     "  in that directory will be the first thing loaded.\n"
  95     "\n"
  96     "  Specifying --root allows GN to do builds in a specific directory\n"
  97     "  regardless of the current directory.\n"
  98     "\n"
  99     "Examples\n"
 100     "\n"
 101     "  gn gen //out/Default --root=/home/baracko/src\n"
 102     "\n"
 103     "  gn desc //out/Default --root=\"C:\\Users\\BObama\\My Documents\\foo\"\n";
 104
 105 const char kThreads[] = "threads";
 106 const char kThreads_HelpShort[] =
 107     "--threads: Specify number of worker threads.";
 108 const char kThreads_Help[] =
 109     "--threads: Specify number of worker threads.\n"
 110     "\n"
 111     "  GN runs many threads to load and run build files. This can make\n"
 112     "  debugging challenging. Or you may want to experiment with different\n"
 113     "  values to see how it affects performance.\n"
 114     "\n"
 115     "  The parameter is the number of worker threads. This does not count the\n"
 116     "  main thread (so there are always at least two).\n"
 117     "\n"
 118     "Examples\n"
 119     "\n"
 120     "  gen gen out/Default --threads=1\n";
 121
 122 const char kTime[] = "time";
 123 const char kTime_HelpShort[] =
 124     "--time: Outputs a summary of how long everything took.";
 125 const char kTime_Help[] =
 126     "--time: Outputs a summary of how long everything took.\n"
 127     "\n"
 128     "  Hopefully self-explanatory.\n"
 129     "\n"
 130     "Examples\n"
 131     "\n"
 132     "  gn gen out/Default --time\n";
 133
 134 const char kTracelog[] = "tracelog";
 135 const char kTracelog_HelpShort[] =
 136     "--tracelog: Writes a Chrome-compatible trace log to the given file.";
 137 const char kTracelog_Help[] =
 138     "--tracelog: Writes a Chrome-compatible trace log to the given file.\n"
 139     "\n"
 140     "  The trace log will show file loads, executions, scripts, and writes.\n"
 141     "  This allows performance analysis of the generation step.\n"
 142     "\n"
 143     "  To view the trace, open Chrome and navigate to \"chrome://tracing/\",\n"
 144     "  then press \"Load\" and specify the file you passed to this parameter.\n"
 145     "\n"
 146     "Examples\n"
 147     "\n"
 148     "  gn gen out/Default --tracelog=mytrace.trace\n";
 149
 150 const char kVerbose[] = "v";
 151 const char kVerbose_HelpShort[] =
 152     "-v: Verbose logging.";
 153 const char kVerbose_Help[] =
 154     "-v: Verbose logging.\n"
 155     "\n"
 156     "  This will spew logging events to the console for debugging issues.\n"
 157     "  Good luck!\n";
 158
 159 const char kVersion[] = "version";
 160 const char kVersion_HelpShort[] =
 161     "--version: Prints the GN version number and exits.";
 162 // It's impossible to see this since gn_main prints the version and exits
 163 // immediately if this switch is used.
 164 const char kVersion_Help[] = "";
 165
 166 // -----------------------------------------------------------------------------
 167
 168 SwitchInfo::SwitchInfo()
 169     : short_help(""),
 170       long_help("") {
 171 }
 172
 173 SwitchInfo::SwitchInfo(const char* short_help, const char* long_help)
 174     : short_help(short_help),
 175       long_help(long_help) {
 176 }
 177
 178 #define INSERT_VARIABLE(var) \
 179     info_map[k##var] = SwitchInfo(k##var##_HelpShort, k##var##_Help);
 180
 181 const SwitchInfoMap& GetSwitches() {
 182   static SwitchInfoMap info_map;
 183   if (info_map.empty()) {
 184     INSERT_VARIABLE(Args)
 185     INSERT_VARIABLE(Color)
 186     INSERT_VARIABLE(Dotfile)
 187     INSERT_VARIABLE(NoColor)
 188     INSERT_VARIABLE(Root)
 189     INSERT_VARIABLE(Quiet)
 190     INSERT_VARIABLE(Time)
 191     INSERT_VARIABLE(Tracelog)
 192     INSERT_VARIABLE(Verbose)
 193     INSERT_VARIABLE(Version)
 194   }
 195   return info_map;
 196 }
 197
 198 #undef INSERT_VARIABLE
 199
 200 }  // namespace switches