tools/gn/function_get_target_outputs.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/build_settings.h"
   6 #include "tools/gn/file_template.h"
   7 #include "tools/gn/functions.h"
   8 #include "tools/gn/ninja_helper.h"
   9 #include "tools/gn/parse_tree.h"
  10 #include "tools/gn/settings.h"
  11 #include "tools/gn/target.h"
  12 #include "tools/gn/value.h"
  13
  14 namespace functions {
  15
  16 namespace {
  17
  18 void GetOutputsForTarget(const Settings* settings,
  19                          const Target* target,
  20                          std::vector<std::string>* ret) {
  21   switch (target->output_type()) {
  22     case Target::ACTION:
  23     case Target::COPY_FILES: {
  24       // Actions and copy targets: return the outputs specified.
  25       const std::vector<SourceFile>& outs = target->action_values().outputs();
  26       ret->reserve(outs.size());
  27       for (size_t i = 0; i < outs.size(); i++)
  28         ret->push_back(outs[i].value());
  29       break;
  30     }
  31
  32     case Target::ACTION_FOREACH: {
  33       // Action_foreach: return the result of the template in the outputs.
  34       FileTemplate file_template(settings, target->action_values().outputs());
  35       const std::vector<SourceFile>& sources = target->sources();
  36       for (size_t i = 0; i < sources.size(); i++)
  37         file_template.Apply(sources[i], ret);
  38       break;
  39     }
  40
  41     case Target::EXECUTABLE:
  42     case Target::SHARED_LIBRARY:
  43     case Target::STATIC_LIBRARY:
  44       // Return the resulting binary file. Currently, fall through to the
  45       // Ninja helper below which will compute the main output name.
  46       //
  47       // TODO(brettw) some targets have secondary files which should go into
  48       // the list after the main (like shared libraries on Windows have an
  49       // import library).
  50     case Target::GROUP:
  51     case Target::SOURCE_SET: {
  52       // These return the stamp file, which is computed by the NinjaHelper.
  53       NinjaHelper helper(settings->build_settings());
  54       OutputFile output_file = helper.GetTargetOutputFile(target);
  55
  56       // The output file is relative to the build dir.
  57       std::string absolute_output_file =
  58           settings->build_settings()->build_dir().value();
  59       absolute_output_file.append(output_file.value());
  60
  61       ret->push_back(absolute_output_file);
  62       break;
  63     }
  64
  65     default:
  66       NOTREACHED();
  67   }
  68 }
  69
  70 }  // namespace
  71
  72 const char kGetTargetOutputs[] = "get_target_outputs";
  73 const char kGetTargetOutputs_HelpShort[] =
  74     "get_target_outputs: [file list] Get the list of outputs from a target.";
  75 const char kGetTargetOutputs_Help[] =
  76     "get_target_outputs: [file list] Get the list of outputs from a target.\n"
  77     "\n"
  78     "  get_target_outputs(target_label)\n"
  79     "\n"
  80     "  Returns a list of output files for the named target. The named target\n"
  81     "  must have been previously defined in the current file before this\n"
  82     "  function is called (it can't reference targets in other files because\n"
  83     "  there isn't a defined execution order, and it obviously can't\n"
  84     "  reference targets that are defined after the function call).\n"
  85     "\n"
  86     "Return value\n"
  87     "\n"
  88     "  The names in the resulting list will be absolute file paths (normally\n"
  89     "  like \"//out/Debug/bar.exe\", depending on the build directory).\n"
  90     "\n"
  91     "  action targets: this will just return the files specified in the\n"
  92     "  \"outputs\" variable of the target.\n"
  93     "\n"
  94     "  action_foreach targets: this will return the result of applying\n"
  95     "  the output template to the sources (see \"gn help source_expansion\").\n"
  96     "  This will be the same result (though with guaranteed absolute file\n"
  97     "  paths), as process_file_template will return for those inputs\n"
  98     "  (see \"gn help process_file_template\").\n"
  99     "\n"
 100     "  binary targets (executables, libraries): this will return a list\n"
 101     "  of the resulting binary file(s). The \"main output\" (the actual\n"
 102     "  binary or library) will always be the 0th element in the result.\n"
 103     "  Depending on the platform and output type, there may be other output\n"
 104     "  files as well (like import libraries) which will follow.\n"
 105     "\n"
 106     "  source sets and groups: this will return a list containing the path of\n"
 107     "  the \"stamp\" file that Ninja will produce once all outputs are\n"
 108     "  generated. This probably isn't very useful.\n"
 109     "\n"
 110     "Example\n"
 111     "\n"
 112     "  # Say this action generates a bunch of C source files.\n"
 113     "  action_foreach(\"my_action\") {\n"
 114     "    sources = [ ... ]\n"
 115     "    outputs = [ ... ]\n"
 116     "  }\n"
 117     "\n"
 118     "  # Compile the resulting source files into a source set.\n"
 119     "  source_set(\"my_lib\") {\n"
 120     "    sources = get_target_outputs(\":my_action\")\n"
 121     "  }\n";
 122
 123 Value RunGetTargetOutputs(Scope* scope,
 124                           const FunctionCallNode* function,
 125                           const std::vector<Value>& args,
 126                           Err* err) {
 127   if (args.size() != 1) {
 128     *err = Err(function, "Expected one argument.");
 129     return Value();
 130   }
 131
 132   // Resolve the requested label.
 133   Label label = Label::Resolve(scope->GetSourceDir(),
 134                                ToolchainLabelForScope(scope), args[0], err);
 135   if (label.is_null())
 136     return Value();
 137
 138   // Find the referenced target. The targets previously encountered in this
 139   // scope will have been stashed in the item collector (they'll be dispatched
 140   // when this file is done running) so we can look through them.
 141   const Target* target = NULL;
 142   Scope::ItemVector* collector = scope->GetItemCollector();
 143   if (!collector) {
 144     *err = Err(function, "No targets defined in this context.");
 145     return Value();
 146   }
 147   for (size_t i = 0; i < collector->size(); i++) {
 148     const Item* item = (*collector)[i]->get();
 149     if (item->label() != label)
 150       continue;
 151
 152     const Target* as_target = item->AsTarget();
 153     if (!as_target) {
 154       *err = Err(function, "Label does not refer to a target.",
 155           label.GetUserVisibleName(false) +
 156           "\nrefers to a " + item->GetItemTypeName());
 157       return Value();
 158     }
 159     target = as_target;
 160     break;
 161   }
 162
 163   if (!target) {
 164     *err = Err(function, "Target not found in this context.",
 165         label.GetUserVisibleName(false) +
 166         "\nwas not found. get_target_outputs() can only be used for targets\n"
 167         "previously defined in the current file.");
 168     return Value();
 169   }
 170
 171   std::vector<std::string> files;
 172   GetOutputsForTarget(scope->settings(), target, &files);
 173
 174   Value ret(function, Value::LIST);
 175   ret.list_value().reserve(files.size());
 176   for (size_t i = 0; i < files.size(); i++)
 177     ret.list_value().push_back(Value(function, files[i]));
 178
 179   return ret;
 180 }
 181
 182 }  // namespace functions