Allow remote execution of link actions.

This CL adds a remoteexec package that allows adding a configurable RBE
prefix to the template.

Test: built aosp crosshatch userdebug with and without RBE_CXX_LINKS.
Change-Id: Ica920c3d7f79f2996210b9cbd448126451c1707c

1 files changed, 155 insertions, 0 deletions

diff --git a/remoteexec/remoteexec.go b/remoteexec/remoteexec.go
new file mode 100644
index 000000000..d43dc6c01
--- /dev/null
+++ b/remoteexec/remoteexec.go
@@ -0,0 +1,155 @@
+// Copyright 2020 Google Inc. 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 remoteexec
+
+import (
+	"sort"
+	"strings"
+
+	"android/soong/android"
+
+	"github.com/google/blueprint"
+)
+
+const (
+	// ContainerImageKey is the key identifying the container image in the platform spec.
+	ContainerImageKey = "container-image"
+
+	// PoolKey is the key identifying the pool to use for remote execution.
+	PoolKey = "Pool"
+
+	// DefaultImage is the default container image used for Android remote execution. The
+	// image was built with the Dockerfile at
+	// https://android.googlesource.com/platform/prebuilts/remoteexecution-client/+/refs/heads/master/docker/Dockerfile
+	DefaultImage = "docker://gcr.io/androidbuild-re-dockerimage/android-build-remoteexec-image@sha256:582efb38f0c229ea39952fff9e132ccbe183e14869b39888010dacf56b360d62"
+
+	// DefaultWrapperPath is the default path to the remote execution wrapper.
+	DefaultWrapperPath = "prebuilts/remoteexecution-client/live/rewrapper"
+
+	// DefaultPool is the name of the pool to use for remote execution when none is specified.
+	DefaultPool = "default"
+
+	// LocalExecStrategy is the exec strategy to indicate that the action should be run locally.
+	LocalExecStrategy = "local"
+
+	// RemoteExecStrategy is the exec strategy to indicate that the action should be run
+	// remotely.
+	RemoteExecStrategy = "remote"
+
+	// RemoteLocalFallbackExecStrategy is the exec strategy to indicate that the action should
+	// be run remotely and fallback to local execution if remote fails.
+	RemoteLocalFallbackExecStrategy = "remote_local_fallback"
+)
+
+var (
+	defaultLabels       = map[string]string{"type": "tool"}
+	defaultExecStrategy = LocalExecStrategy
+	pctx                = android.NewPackageContext("android/soong/remoteexec")
+)
+
+// REParams holds information pertinent to the remote execution of a rule.
+type REParams struct {
+	// Platform is the key value pair used for remotely executing the action.
+	Platform map[string]string
+	// Labels is a map of labels that identify the rule.
+	Labels map[string]string
+	// ExecStrategy is the remote execution strategy: remote, local, or remote_local_fallback.
+	ExecStrategy string
+	// Inputs is a list of input paths or ninja variables.
+	Inputs []string
+	// RSPFile is the name of the ninja variable used by the rule as a placeholder for an rsp
+	// input.
+	RSPFile string
+	// OutputFiles is a list of output file paths or ninja variables as placeholders for rule
+	// outputs.
+	OutputFiles []string
+	// ToolchainInputs is a list of paths or ninja variables pointing to the location of
+	// toolchain binaries used by the rule.
+	ToolchainInputs []string
+}
+
+func init() {
+	pctx.VariableFunc("Wrapper", func(ctx android.PackageVarContext) string {
+		if override := ctx.Config().Getenv("RBE_WRAPPER"); override != "" {
+			return override
+		}
+		return DefaultWrapperPath
+	})
+}
+
+// Generate the remote execution wrapper template to be added as a prefix to the rule's command.
+func (r *REParams) Template() string {
+	template := "${remoteexec.Wrapper}"
+
+	var kvs []string
+	labels := r.Labels
+	if len(labels) == 0 {
+		labels = defaultLabels
+	}
+	for k, v := range labels {
+		kvs = append(kvs, k+"="+v)
+	}
+	sort.Strings(kvs)
+	template += " --labels=" + strings.Join(kvs, ",")
+
+	var platform []string
+	for k, v := range r.Platform {
+		if v == "" {
+			continue
+		}
+		platform = append(platform, k+"="+v)
+	}
+	if _, ok := r.Platform[ContainerImageKey]; !ok {
+		platform = append(platform, ContainerImageKey+"="+DefaultImage)
+	}
+	if platform != nil {
+		sort.Strings(platform)
+		template += " --platform=\"" + strings.Join(platform, ",") + "\""
+	}
+
+	strategy := r.ExecStrategy
+	if strategy == "" {
+		strategy = defaultExecStrategy
+	}
+	template += " --exec_strategy=" + strategy
+
+	if len(r.Inputs) > 0 {
+		template += " --inputs=" + strings.Join(r.Inputs, ",")
+	}
+
+	if r.RSPFile != "" {
+		template += " --input_list_paths=" + r.RSPFile
+	}
+
+	if len(r.OutputFiles) > 0 {
+		template += " --output_files=" + strings.Join(r.OutputFiles, ",")
+	}
+
+	if len(r.ToolchainInputs) > 0 {
+		template += " --toolchain_inputs=" + strings.Join(r.ToolchainInputs, ",")
+	}
+
+	return template + " -- "
+}
+
+// StaticRules returns a pair of rules based on the given RuleParams, where the first rule is a
+// locally executable rule and the second rule is a remotely executable rule.
+func StaticRules(ctx android.PackageContext, name string, ruleParams blueprint.RuleParams, reParams *REParams, commonArgs []string, reArgs []string) (blueprint.Rule, blueprint.Rule) {
+	ruleParamsRE := ruleParams
+	ruleParamsRE.Command = reParams.Template() + ruleParamsRE.Command
+
+	return ctx.AndroidStaticRule(name, ruleParams, commonArgs...),
+		ctx.AndroidRemoteStaticRule(name+"RE", android.RemoteRuleSupports{RBE: true}, ruleParamsRE, append(commonArgs, reArgs...)...)
+}