tools/gn/ninja_helper.cc

   1 // Copyright (c) 2013 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/ninja_helper.h"
   6
   7 #include "base/logging.h"
   8 #include "base/strings/string_util.h"
   9 #include "tools/gn/filesystem_utils.h"
  10 #include "tools/gn/string_utils.h"
  11 #include "tools/gn/target.h"
  12
  13 namespace {
  14
  15 const char kLibDirWithSlash[] = "lib/";
  16 const char kObjectDirNoSlash[] = "obj";
  17
  18 }  // namespace
  19
  20 NinjaHelper::NinjaHelper(const BuildSettings* build_settings)
  21     : build_settings_(build_settings) {
  22   build_to_src_no_last_slash_ = build_settings->build_to_source_dir_string();
  23   if (!build_to_src_no_last_slash_.empty() &&
  24       build_to_src_no_last_slash_[build_to_src_no_last_slash_.size() - 1] ==
  25           '/')
  26     build_to_src_no_last_slash_.resize(build_to_src_no_last_slash_.size() - 1);
  27
  28   build_to_src_system_no_last_slash_ = build_to_src_no_last_slash_;
  29 }
  30
  31 NinjaHelper::~NinjaHelper() {
  32 }
  33
  34 std::string NinjaHelper::GetTopleveOutputDir() const {
  35   return kObjectDirNoSlash;
  36 }
  37
  38 OutputFile NinjaHelper::GetTargetOutputDir(const Target* target) const {
  39   OutputFile ret(target->settings()->toolchain_output_subdir());
  40   ret.value().append(kObjectDirNoSlash);
  41   AppendStringPiece(&ret.value(),
  42                     target->label().dir().SourceAbsoluteWithOneSlash());
  43   return ret;
  44 }
  45
  46 OutputFile NinjaHelper::GetNinjaFileForTarget(const Target* target) const {
  47   OutputFile ret = GetTargetOutputDir(target);
  48   ret.value().append(target->label().name());
  49   ret.value().append(".ninja");
  50   return ret;
  51 }
  52
  53 OutputFile NinjaHelper::GetNinjaFileForToolchain(
  54     const Settings* settings) const {
  55   OutputFile ret;
  56   ret.value().append(settings->toolchain_output_subdir().value());
  57   ret.value().append("toolchain.ninja");
  58   return ret;
  59 }
  60
  61 // In Python, GypPathToUniqueOutput does the qualification. The only case where
  62 // the Python version doesn't qualify the name is for target outputs, which we
  63 // handle in a separate function.
  64 OutputFile NinjaHelper::GetOutputFileForSource(
  65     const Target* target,
  66     const SourceFile& source,
  67     SourceFileType type) const {
  68   // Extract the filename and remove the extension (keep the dot).
  69   base::StringPiece filename = FindFilename(&source.value());
  70   std::string name(filename.data(), filename.size());
  71   size_t extension_offset = FindExtensionOffset(name);
  72   CHECK(extension_offset != std::string::npos);
  73   name.resize(extension_offset);
  74
  75   // Append the new extension.
  76   switch (type) {
  77     case SOURCE_ASM:
  78     case SOURCE_C:
  79     case SOURCE_CC:
  80     case SOURCE_M:
  81     case SOURCE_MM:
  82     case SOURCE_S:
  83       name.append(target->settings()->IsWin() ? "obj" : "o");
  84       break;
  85
  86     case SOURCE_RC:
  87       name.append("res");
  88       break;
  89
  90     // Pass .o/.obj files through unchanged.
  91     case SOURCE_O: {
  92       // System-absolute file names get preserved (they don't need to be
  93       // rebased relative to the build dir).
  94       if (source.is_system_absolute())
  95         return OutputFile(source.value());
  96
  97       // Files that are already inside the build dir should not be made
  98       // relative to the source tree. Doing so will insert an unnecessary
  99       // "../.." into the path which won't match the corresponding target
 100       // name in ninja.
 101       CHECK(build_settings_->build_dir().is_source_absolute());
 102       CHECK(source.is_source_absolute());
 103       if (StartsWithASCII(source.value(),
 104                           build_settings_->build_dir().value(),
 105                           true)) {
 106         return OutputFile(
 107             source.value().substr(
 108                 build_settings_->build_dir().value().size()));
 109       }
 110
 111       // Construct the relative location of the file from the build dir.
 112       OutputFile ret(build_to_src_no_last_slash());
 113       source.SourceAbsoluteWithOneSlash().AppendToString(&ret.value());
 114       return ret;
 115     }
 116
 117     case SOURCE_H:
 118     case SOURCE_UNKNOWN:
 119       NOTREACHED();
 120       return OutputFile();
 121   }
 122
 123   // Use the scheme <path>/<target>.<name>.<extension> so that all output
 124   // names are unique to different targets.
 125
 126   // This will look like "obj" or "toolchain_name/obj".
 127   OutputFile ret(target->settings()->toolchain_output_subdir());
 128   ret.value().append(kObjectDirNoSlash);
 129
 130   // Find the directory, assume it starts with two slashes, and trim to one.
 131   base::StringPiece dir = FindDir(&source.value());
 132   CHECK(dir.size() >= 2 && dir[0] == '/' && dir[1] == '/')
 133       << "Source file isn't in the source repo: " << dir;
 134   AppendStringPiece(&ret.value(), dir.substr(1));
 135
 136   ret.value().append(target->label().name());
 137   ret.value().append(".");
 138   ret.value().append(name);
 139   return ret;
 140 }
 141
 142 OutputFile NinjaHelper::GetTargetOutputFile(const Target* target) const {
 143   OutputFile ret;
 144
 145   // Use the output name if given, fall back to target name if not.
 146   const std::string& name = target->output_name().empty() ?
 147       target->label().name() : target->output_name();
 148
 149   // This is prepended to the output file name. Some platforms get "lib"
 150   // prepended to library names. but be careful not to make a duplicate (e.g.
 151   // some targets like "libxml" already have the "lib" in the name).
 152   const char* prefix;
 153   if (!target->settings()->IsWin() &&
 154       (target->output_type() == Target::SHARED_LIBRARY ||
 155        target->output_type() == Target::STATIC_LIBRARY) &&
 156       name.compare(0, 3, "lib") != 0)
 157     prefix = "lib";
 158   else
 159     prefix = "";
 160
 161   const char* extension;
 162   if (target->output_extension().empty()) {
 163     if (target->output_type() == Target::GROUP ||
 164         target->output_type() == Target::SOURCE_SET ||
 165         target->output_type() == Target::COPY_FILES ||
 166         target->output_type() == Target::ACTION ||
 167         target->output_type() == Target::ACTION_FOREACH) {
 168       extension = "stamp";
 169     } else {
 170       extension = GetExtensionForOutputType(target->output_type(),
 171                                             target->settings()->target_os());
 172     }
 173   } else {
 174     extension = target->output_extension().c_str();
 175   }
 176
 177   // Everything goes into the toolchain directory (which will be empty for the
 178   // default toolchain, and will end in a slash otherwise).
 179   ret.value().append(target->settings()->toolchain_output_subdir().value());
 180
 181   // Binaries and loadable libraries go into the toolchain root.
 182   if (target->output_type() == Target::EXECUTABLE ||
 183       (target->settings()->IsMac() &&
 184           (target->output_type() == Target::SHARED_LIBRARY ||
 185            target->output_type() == Target::STATIC_LIBRARY)) ||
 186       (target->settings()->IsWin() &&
 187        target->output_type() == Target::SHARED_LIBRARY)) {
 188     // Generate a name like "<toolchain>/<prefix><name>.<extension>".
 189     ret.value().append(prefix);
 190     ret.value().append(name);
 191     if (extension[0]) {
 192       ret.value().push_back('.');
 193       ret.value().append(extension);
 194     }
 195     return ret;
 196   }
 197
 198   // Libraries go into the library subdirectory like
 199   // "<toolchain>/lib/<prefix><name>.<extension>".
 200   if (target->output_type() == Target::SHARED_LIBRARY) {
 201     ret.value().append(kLibDirWithSlash);
 202     ret.value().append(prefix);
 203     ret.value().append(name);
 204     if (extension[0]) {
 205       ret.value().push_back('.');
 206       ret.value().append(extension);
 207     }
 208     return ret;
 209   }
 210
 211   // Everything else goes next to the target's .ninja file like
 212   // "<toolchain>/obj/<path>/<name>.<extension>".
 213   ret.value().append(kObjectDirNoSlash);
 214   AppendStringPiece(&ret.value(),
 215                     target->label().dir().SourceAbsoluteWithOneSlash());
 216   ret.value().append(prefix);
 217   ret.value().append(name);
 218   if (extension[0]) {
 219     ret.value().push_back('.');
 220     ret.value().append(extension);
 221   }
 222   return ret;
 223 }
 224
 225 std::string NinjaHelper::GetRulePrefix(const Settings* settings) const {
 226   // Don't prefix the default toolchain so it looks prettier, prefix everything
 227   // else.
 228   if (settings->is_default())
 229     return std::string();  // Default toolchain has no prefix.
 230   return settings->toolchain_label().name() + "_";
 231 }
 232
 233 std::string NinjaHelper::GetRuleForSourceType(const Settings* settings,
 234                                               SourceFileType type) const {
 235   // This function may be hot since it will be called for every source file
 236   // in the tree. We could cache the results to avoid making a string for
 237   // every invocation.
 238   std::string prefix = GetRulePrefix(settings);
 239
 240   if (type == SOURCE_C)
 241     return prefix + "cc";
 242   if (type == SOURCE_CC)
 243     return prefix + "cxx";
 244   if (type == SOURCE_M)
 245     return prefix + "objc";
 246   if (type == SOURCE_MM)
 247     return prefix + "objcxx";
 248   if (type == SOURCE_RC)
 249     return prefix + "rc";
 250   if (type == SOURCE_S)
 251     return prefix + "cc";  // Assembly files just get compiled by CC.
 252
 253   // TODO(brettw) asm files.
 254
 255   // .obj files have no rules to make them (they're already built) so we return
 256   // the enpty string for SOURCE_O.
 257   return std::string();
 258 }