tools/gn/target.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/target.h"
   6
   7 #include "base/bind.h"
   8 #include "base/strings/string_util.h"
   9 #include "base/strings/stringprintf.h"
  10 #include "tools/gn/config_values_extractors.h"
  11 #include "tools/gn/deps_iterator.h"
  12 #include "tools/gn/filesystem_utils.h"
  13 #include "tools/gn/scheduler.h"
  14 #include "tools/gn/substitution_writer.h"
  15
  16 namespace {
  17
  18 typedef std::set<const Config*> ConfigSet;
  19
  20 // Merges the public configs from the given target to the given config list.
  21 void MergePublicConfigsFrom(const Target* from_target,
  22                             UniqueVector<LabelConfigPair>* dest) {
  23   const UniqueVector<LabelConfigPair>& pub = from_target->public_configs();
  24   dest->Append(pub.begin(), pub.end());
  25 }
  26
  27 // Like MergePublicConfigsFrom above except does the "all dependent" ones. This
  28 // additionally adds all configs to the all_dependent_configs_ of the dest
  29 // target given in *all_dest.
  30 void MergeAllDependentConfigsFrom(const Target* from_target,
  31                                   UniqueVector<LabelConfigPair>* dest,
  32                                   UniqueVector<LabelConfigPair>* all_dest) {
  33   for (const auto& pair : from_target->all_dependent_configs()) {
  34     all_dest->push_back(pair);
  35     dest->push_back(pair);
  36   }
  37 }
  38
  39 Err MakeTestOnlyError(const Target* from, const Target* to) {
  40   return Err(from->defined_from(), "Test-only dependency not allowed.",
  41       from->label().GetUserVisibleName(false) + "\n"
  42       "which is NOT marked testonly can't depend on\n" +
  43       to->label().GetUserVisibleName(false) + "\n"
  44       "which is marked testonly. Only targets with \"testonly = true\"\n"
  45       "can depend on other test-only targets.\n"
  46       "\n"
  47       "Either mark it test-only or don't do this dependency.");
  48 }
  49
  50 Err MakeStaticLibDepsError(const Target* from, const Target* to) {
  51   return Err(from->defined_from(),
  52              "Complete static libraries can't depend on static libraries.",
  53              from->label().GetUserVisibleName(false) +
  54                  "\n"
  55                  "which is a complete static library can't depend on\n" +
  56                  to->label().GetUserVisibleName(false) +
  57                  "\n"
  58                  "which is a static library.\n"
  59                  "\n"
  60                  "Use source sets for intermediate targets instead.");
  61 }
  62
  63 }  // namespace
  64
  65 Target::Target(const Settings* settings, const Label& label)
  66     : Item(settings, label),
  67       output_type_(UNKNOWN),
  68       all_headers_public_(true),
  69       check_includes_(true),
  70       complete_static_lib_(false),
  71       testonly_(false),
  72       hard_dep_(false),
  73       toolchain_(NULL) {
  74 }
  75
  76 Target::~Target() {
  77 }
  78
  79 // static
  80 const char* Target::GetStringForOutputType(OutputType type) {
  81   switch (type) {
  82     case UNKNOWN:
  83       return "Unknown";
  84     case GROUP:
  85       return "Group";
  86     case EXECUTABLE:
  87       return "Executable";
  88     case SHARED_LIBRARY:
  89       return "Shared library";
  90     case STATIC_LIBRARY:
  91       return "Static library";
  92     case SOURCE_SET:
  93       return "Source set";
  94     case COPY_FILES:
  95       return "Copy";
  96     case ACTION:
  97       return "Action";
  98     case ACTION_FOREACH:
  99       return "ActionForEach";
 100     default:
 101       return "";
 102   }
 103 }
 104
 105 Target* Target::AsTarget() {
 106   return this;
 107 }
 108
 109 const Target* Target::AsTarget() const {
 110   return this;
 111 }
 112
 113 bool Target::OnResolved(Err* err) {
 114   DCHECK(output_type_ != UNKNOWN);
 115   DCHECK(toolchain_) << "Toolchain should have been set before resolving.";
 116
 117   // Copy our own dependent configs to the list of configs applying to us.
 118   configs_.Append(all_dependent_configs_.begin(), all_dependent_configs_.end());
 119   MergePublicConfigsFrom(this, &configs_);
 120
 121   // Copy our own libs and lib_dirs to the final set. This will be from our
 122   // target and all of our configs. We do this specially since these must be
 123   // inherited through the dependency tree (other flags don't work this way).
 124   for (ConfigValuesIterator iter(this); !iter.done(); iter.Next()) {
 125     const ConfigValues& cur = iter.cur();
 126     all_lib_dirs_.append(cur.lib_dirs().begin(), cur.lib_dirs().end());
 127     all_libs_.append(cur.libs().begin(), cur.libs().end());
 128   }
 129
 130   PullDependentTargetInfo();
 131   PullForwardedDependentConfigs();
 132   PullRecursiveHardDeps();
 133
 134   FillOutputFiles();
 135
 136   if (!CheckVisibility(err))
 137     return false;
 138   if (!CheckTestonly(err))
 139     return false;
 140   if (!CheckNoNestedStaticLibs(err))
 141     return false;
 142
 143   return true;
 144 }
 145
 146 bool Target::IsLinkable() const {
 147   return output_type_ == STATIC_LIBRARY || output_type_ == SHARED_LIBRARY;
 148 }
 149
 150 bool Target::IsFinal() const {
 151   return output_type_ == EXECUTABLE || output_type_ == SHARED_LIBRARY ||
 152          (output_type_ == STATIC_LIBRARY && complete_static_lib_);
 153 }
 154
 155 DepsIteratorRange Target::GetDeps(DepsIterationType type) const {
 156   if (type == DEPS_LINKED) {
 157     return DepsIteratorRange(DepsIterator(
 158         &public_deps_, &private_deps_, nullptr));
 159   }
 160   // All deps.
 161   return DepsIteratorRange(DepsIterator(
 162       &public_deps_, &private_deps_, &data_deps_));
 163 }
 164
 165 std::string Target::GetComputedOutputName(bool include_prefix) const {
 166   DCHECK(toolchain_)
 167       << "Toolchain must be specified before getting the computed output name.";
 168
 169   const std::string& name = output_name_.empty() ? label().name()
 170                                                  : output_name_;
 171
 172   std::string result;
 173   if (include_prefix) {
 174     const Tool* tool = toolchain_->GetToolForTargetFinalOutput(this);
 175     const std::string& prefix = tool->output_prefix();
 176     // Only add the prefix if the name doesn't already have it.
 177     if (!StartsWithASCII(name, prefix, true))
 178       result = prefix;
 179   }
 180
 181   result.append(name);
 182   return result;
 183 }
 184
 185 bool Target::SetToolchain(const Toolchain* toolchain, Err* err) {
 186   DCHECK(!toolchain_);
 187   DCHECK_NE(UNKNOWN, output_type_);
 188   toolchain_ = toolchain;
 189
 190   const Tool* tool = toolchain->GetToolForTargetFinalOutput(this);
 191   if (tool)
 192     return true;
 193
 194   // Tool not specified for this target type.
 195   if (err) {
 196     *err = Err(defined_from(), "This target uses an undefined tool.",
 197         base::StringPrintf(
 198             "The target %s\n"
 199             "of type \"%s\"\n"
 200             "uses toolchain %s\n"
 201             "which doesn't have the tool \"%s\" defined.\n\n"
 202             "Alas, I can not continue.",
 203             label().GetUserVisibleName(false).c_str(),
 204             GetStringForOutputType(output_type_),
 205             label().GetToolchainLabel().GetUserVisibleName(false).c_str(),
 206             Toolchain::ToolTypeToName(
 207                 toolchain->GetToolTypeForTargetFinalOutput(this)).c_str()));
 208   }
 209   return false;
 210 }
 211
 212 void Target::PullDependentTargetInfo() {
 213   // Gather info from our dependents we need.
 214   for (const auto& pair : GetDeps(DEPS_LINKED)) {
 215     const Target* dep = pair.ptr;
 216     MergeAllDependentConfigsFrom(dep, &configs_, &all_dependent_configs_);
 217     MergePublicConfigsFrom(dep, &configs_);
 218
 219     // Direct dependent libraries.
 220     if (dep->output_type() == STATIC_LIBRARY ||
 221         dep->output_type() == SHARED_LIBRARY ||
 222         dep->output_type() == SOURCE_SET)
 223       inherited_libraries_.push_back(dep);
 224
 225     // Inherited libraries and flags are inherited across static library
 226     // boundaries.
 227     if (!dep->IsFinal()) {
 228       inherited_libraries_.Append(dep->inherited_libraries().begin(),
 229                                   dep->inherited_libraries().end());
 230
 231       // Inherited library settings.
 232       all_lib_dirs_.append(dep->all_lib_dirs());
 233       all_libs_.append(dep->all_libs());
 234     }
 235   }
 236 }
 237
 238 void Target::PullForwardedDependentConfigs() {
 239   // Pull public configs from each of our dependency's public deps.
 240   for (const auto& dep : public_deps_)
 241     PullForwardedDependentConfigsFrom(dep.ptr);
 242
 243   // Forward public configs if explicitly requested.
 244   for (const auto& dep : forward_dependent_configs_) {
 245     const Target* from_target = dep.ptr;
 246
 247     // The forward_dependent_configs_ must be in the deps (public or private)
 248     // already, so we don't need to bother copying to our configs, only
 249     // forwarding.
 250     DCHECK(std::find_if(private_deps_.begin(), private_deps_.end(),
 251                         LabelPtrPtrEquals<Target>(from_target)) !=
 252                private_deps_.end() ||
 253            std::find_if(public_deps_.begin(), public_deps_.end(),
 254                         LabelPtrPtrEquals<Target>(from_target)) !=
 255                public_deps_.end());
 256
 257     PullForwardedDependentConfigsFrom(from_target);
 258   }
 259 }
 260
 261 void Target::PullForwardedDependentConfigsFrom(const Target* from) {
 262   public_configs_.Append(from->public_configs().begin(),
 263                          from->public_configs().end());
 264 }
 265
 266 void Target::PullRecursiveHardDeps() {
 267   for (const auto& pair : GetDeps(DEPS_LINKED)) {
 268     if (pair.ptr->hard_dep())
 269       recursive_hard_deps_.insert(pair.ptr);
 270
 271     // Android STL doesn't like insert(begin, end) so do it manually.
 272     // TODO(brettw) this can be changed to
 273     // insert(iter.target()->begin(), iter.target()->end())
 274     // when Android uses a better STL.
 275     for (std::set<const Target*>::const_iterator cur =
 276              pair.ptr->recursive_hard_deps().begin();
 277          cur != pair.ptr->recursive_hard_deps().end(); ++cur)
 278       recursive_hard_deps_.insert(*cur);
 279   }
 280 }
 281
 282 void Target::FillOutputFiles() {
 283   const Tool* tool = toolchain_->GetToolForTargetFinalOutput(this);
 284   switch (output_type_) {
 285     case GROUP:
 286     case SOURCE_SET:
 287     case COPY_FILES:
 288     case ACTION:
 289     case ACTION_FOREACH: {
 290       // These don't get linked to and use stamps which should be the first
 291       // entry in the outputs. These stamps are named
 292       // "<target_out_dir>/<targetname>.stamp".
 293       dependency_output_file_ = GetTargetOutputDirAsOutputFile(this);
 294       dependency_output_file_.value().append(GetComputedOutputName(true));
 295       dependency_output_file_.value().append(".stamp");
 296       break;
 297     }
 298     case EXECUTABLE:
 299       // Executables don't get linked to, but the first output is used for
 300       // dependency management.
 301       CHECK_GE(tool->outputs().list().size(), 1u);
 302       dependency_output_file_ =
 303           SubstitutionWriter::ApplyPatternToLinkerAsOutputFile(
 304               this, tool, tool->outputs().list()[0]);
 305       break;
 306     case STATIC_LIBRARY:
 307       // Static libraries both have dependencies and linking going off of the
 308       // first output.
 309       CHECK(tool->outputs().list().size() >= 1);
 310       link_output_file_ = dependency_output_file_ =
 311           SubstitutionWriter::ApplyPatternToLinkerAsOutputFile(
 312               this, tool, tool->outputs().list()[0]);
 313       break;
 314     case SHARED_LIBRARY:
 315       CHECK(tool->outputs().list().size() >= 1);
 316       if (tool->link_output().empty() && tool->depend_output().empty()) {
 317         // Default behavior, use the first output file for both.
 318         link_output_file_ = dependency_output_file_ =
 319             SubstitutionWriter::ApplyPatternToLinkerAsOutputFile(
 320                 this, tool, tool->outputs().list()[0]);
 321       } else {
 322         // Use the tool-specified ones.
 323         if (!tool->link_output().empty()) {
 324           link_output_file_ =
 325               SubstitutionWriter::ApplyPatternToLinkerAsOutputFile(
 326                   this, tool, tool->link_output());
 327         }
 328         if (!tool->depend_output().empty()) {
 329           dependency_output_file_ =
 330               SubstitutionWriter::ApplyPatternToLinkerAsOutputFile(
 331                   this, tool, tool->depend_output());
 332         }
 333       }
 334       break;
 335     case UNKNOWN:
 336     default:
 337       NOTREACHED();
 338   }
 339 }
 340
 341 bool Target::CheckVisibility(Err* err) const {
 342   for (const auto& pair : GetDeps(DEPS_ALL)) {
 343     if (!Visibility::CheckItemVisibility(this, pair.ptr, err))
 344       return false;
 345   }
 346   return true;
 347 }
 348
 349 bool Target::CheckTestonly(Err* err) const {
 350   // If the current target is marked testonly, it can include both testonly
 351   // and non-testonly targets, so there's nothing to check.
 352   if (testonly())
 353     return true;
 354
 355   // Verify no deps have "testonly" set.
 356   for (const auto& pair : GetDeps(DEPS_ALL)) {
 357     if (pair.ptr->testonly()) {
 358       *err = MakeTestOnlyError(this, pair.ptr);
 359       return false;
 360     }
 361   }
 362
 363   return true;
 364 }
 365
 366 bool Target::CheckNoNestedStaticLibs(Err* err) const {
 367   // If the current target is not a complete static library, it can depend on
 368   // static library targets with no problem.
 369   if (!(output_type() == Target::STATIC_LIBRARY && complete_static_lib()))
 370     return true;
 371
 372   // Verify no deps are static libraries.
 373   for (const auto& pair : GetDeps(DEPS_ALL)) {
 374     if (pair.ptr->output_type() == Target::STATIC_LIBRARY) {
 375       *err = MakeStaticLibDepsError(this, pair.ptr);
 376       return false;
 377     }
 378   }
 379
 380   // Verify no inherited libraries are static libraries.
 381   for (const auto& lib : inherited_libraries()) {
 382     if (lib->output_type() == Target::STATIC_LIBRARY) {
 383       *err = MakeStaticLibDepsError(this, lib);
 384       return false;
 385     }
 386   }
 387   return true;
 388 }