| // Copyright 2017 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.devtools.build.lib.rules.platform; |
| |
| import static com.google.devtools.build.lib.packages.Attribute.attr; |
| |
| import com.google.devtools.build.lib.analysis.RuleDefinition; |
| import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment; |
| import com.google.devtools.build.lib.analysis.platform.ConstraintSettingInfo; |
| import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo; |
| import com.google.devtools.build.lib.packages.BuildType; |
| import com.google.devtools.build.lib.packages.RuleClass; |
| import com.google.devtools.build.lib.util.FileTypeSet; |
| |
| /** Rule definition for {@link ConstraintValue}. */ |
| public class ConstraintValueRule implements RuleDefinition { |
| public static final String RULE_NAME = "constraint_value"; |
| public static final String CONSTRAINT_SETTING_ATTR = "constraint_setting"; |
| |
| @Override |
| public RuleClass build(RuleClass.Builder builder, RuleDefinitionEnvironment env) { |
| return builder |
| .advertiseProvider(ConstraintValueInfo.class) |
| /* <!-- #BLAZE_RULE(constraint_value).ATTRIBUTE(constraint_setting) --> |
| The <code>constraint_setting</code> for which this <code>constraint_value</code> is a |
| possible choice. |
| <!-- #END_BLAZE_RULE.ATTRIBUTE --> */ |
| .add( |
| attr(CONSTRAINT_SETTING_ATTR, BuildType.LABEL) |
| .mandatory() |
| .allowedRuleClasses(ConstraintSettingRule.RULE_NAME) |
| .allowedFileTypes(FileTypeSet.NO_FILE) |
| .mandatoryProviders(ConstraintSettingInfo.PROVIDER.id())) |
| .build(); |
| } |
| |
| @Override |
| public Metadata getMetadata() { |
| return Metadata.builder() |
| .name(RULE_NAME) |
| .ancestors(PlatformBaseRule.class) |
| .factoryClass(ConstraintValue.class) |
| .build(); |
| } |
| } |
| /*<!-- #BLAZE_RULE (NAME = constraint_value, TYPE = OTHER, FAMILY = Platform)[GENERIC_RULE] --> |
| |
| This rule introduces a new value for a given constraint type. See the |
| <a href="https://docs.bazel.build/versions/master/platforms.html">Platforms</a> page for more |
| details. |
| |
| <h4 id="constraint_value_examples">Example</h4> |
| <p>The following creates a new possible value for the predefined <code>constraint_value</code> |
| representing cpu architecture. |
| <pre class="code"> |
| constraint_value( |
| name = "mips", |
| constraint_setting = "@bazel_tools//platforms:cpu", |
| ) |
| </pre> |
| |
| Platforms can then declare that they have the <code>mips</code> architecture as an alternative to |
| <code>x86_64</code>, <code>arm</code>, and so on. |
| |
| <!-- #END_BLAZE_RULE -->*/ |