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/action_target_generator.h"
6
7 #include "tools/gn/build_settings.h"
8 #include "tools/gn/err.h"
9 #include "tools/gn/filesystem_utils.h"
10 #include "tools/gn/parse_tree.h"
11 #include "tools/gn/scope.h"
12 #include "tools/gn/value.h"
13 #include "tools/gn/value_extractors.h"
14 #include "tools/gn/variables.h"
15
ActionTargetGenerator(Target * target,Scope * scope,const FunctionCallNode * function_call,Target::OutputType type,Err * err)16 ActionTargetGenerator::ActionTargetGenerator(
17 Target* target,
18 Scope* scope,
19 const FunctionCallNode* function_call,
20 Target::OutputType type,
21 Err* err)
22 : TargetGenerator(target, scope, function_call, err),
23 output_type_(type) {
24 }
25
~ActionTargetGenerator()26 ActionTargetGenerator::~ActionTargetGenerator() {
27 }
28
DoRun()29 void ActionTargetGenerator::DoRun() {
30 target_->set_output_type(output_type_);
31
32 if (!FillSources())
33 return;
34 if (output_type_ == Target::ACTION_FOREACH && target_->sources().empty()) {
35 // Foreach rules must always have some sources to have an effect.
36 *err_ = Err(function_call_, "action_foreach target has no sources.",
37 "If you don't specify any sources, there is nothing to run your\n"
38 "script over.");
39 return;
40 }
41
42 if (!FillInputs())
43 return;
44
45 if (!FillScript())
46 return;
47
48 if (!FillScriptArgs())
49 return;
50
51 if (!FillOutputs(output_type_ == Target::ACTION_FOREACH))
52 return;
53
54 if (!FillDepfile())
55 return;
56
57 if (!CheckOutputs())
58 return;
59
60 // Action outputs don't depend on the current toolchain so we can skip adding
61 // that dependency.
62 }
63
FillScript()64 bool ActionTargetGenerator::FillScript() {
65 // If this gets called, the target type requires a script, so error out
66 // if it doesn't have one.
67 const Value* value = scope_->GetValue(variables::kScript, true);
68 if (!value) {
69 *err_ = Err(function_call_, "This target type requires a \"script\".");
70 return false;
71 }
72 if (!value->VerifyTypeIs(Value::STRING, err_))
73 return false;
74
75 SourceFile script_file =
76 scope_->GetSourceDir().ResolveRelativeFile(value->string_value());
77 if (script_file.value().empty()) {
78 *err_ = Err(*value, "script name is empty");
79 return false;
80 }
81 target_->action_values().set_script(script_file);
82 return true;
83 }
84
FillScriptArgs()85 bool ActionTargetGenerator::FillScriptArgs() {
86 const Value* value = scope_->GetValue(variables::kArgs, true);
87 if (!value)
88 return true;
89 return target_->action_values().args().Parse(*value, err_);
90 }
91
FillDepfile()92 bool ActionTargetGenerator::FillDepfile() {
93 const Value* value = scope_->GetValue(variables::kDepfile, true);
94 if (!value)
95 return true;
96
97 SubstitutionPattern depfile;
98 if (!depfile.Parse(*value, err_))
99 return false;
100 if (!EnsureSubstitutionIsInOutputDir(depfile, *value))
101 return false;
102
103 target_->action_values().set_depfile(depfile);
104 return true;
105 }
106
CheckOutputs()107 bool ActionTargetGenerator::CheckOutputs() {
108 const SubstitutionList& outputs = target_->action_values().outputs();
109 if (outputs.list().empty()) {
110 *err_ = Err(function_call_, "Action has no outputs.",
111 "If you have no outputs, the build system can not tell when your\n"
112 "script needs to be run.");
113 return false;
114 }
115
116 if (output_type_ == Target::ACTION) {
117 if (!outputs.required_types().empty()) {
118 *err_ = Err(function_call_, "Action has patterns in the output.",
119 "An action target should have the outputs completely specified. If\n"
120 "you want to provide a mapping from source to output, use an\n"
121 "\"action_foreach\" target.");
122 return false;
123 }
124 } else if (output_type_ == Target::ACTION_FOREACH) {
125 // A foreach target should always have a pattern in the outputs.
126 if (outputs.required_types().empty()) {
127 *err_ = Err(function_call_,
128 "action_foreach should have a pattern in the output.",
129 "An action_foreach target should have a source expansion pattern in\n"
130 "it to map source file to unique output file name. Otherwise, the\n"
131 "build system can't determine when your script needs to be run.");
132 return false;
133 }
134 }
135 return true;
136 }
137