platform_build_soong/cmd/sbox/sbox.go

277 lines
8.4 KiB
Go

// Copyright 2017 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 main
import (
"errors"
"flag"
"fmt"
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"strings"
)
var (
sandboxesRoot string
rawCommand string
outputRoot string
keepOutDir bool
depfileOut string
)
func init() {
flag.StringVar(&sandboxesRoot, "sandbox-path", "",
"root of temp directory to put the sandbox into")
flag.StringVar(&rawCommand, "c", "",
"command to run")
flag.StringVar(&outputRoot, "output-root", "",
"root of directory to copy outputs into")
flag.BoolVar(&keepOutDir, "keep-out-dir", false,
"whether to keep the sandbox directory when done")
flag.StringVar(&depfileOut, "depfile-out", "",
"file path of the depfile to generate. This value will replace '__SBOX_DEPFILE__' in the command and will be treated as an output but won't be added to __SBOX_OUT_FILES__")
}
func usageViolation(violation string) {
if violation != "" {
fmt.Fprintf(os.Stderr, "Usage error: %s.\n\n", violation)
}
fmt.Fprintf(os.Stderr,
"Usage: sbox -c <commandToRun> --sandbox-path <sandboxPath> --output-root <outputRoot> --overwrite [--depfile-out depFile] <outputFile> [<outputFile>...]\n"+
"\n"+
"Deletes <outputRoot>,"+
"runs <commandToRun>,"+
"and moves each <outputFile> out of <sandboxPath> and into <outputRoot>\n")
flag.PrintDefaults()
os.Exit(1)
}
func main() {
flag.Usage = func() {
usageViolation("")
}
flag.Parse()
error := run()
if error != nil {
fmt.Fprintln(os.Stderr, error)
os.Exit(1)
}
}
func findAllFilesUnder(root string) (paths []string) {
paths = []string{}
filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
if !info.IsDir() {
relPath, err := filepath.Rel(root, path)
if err != nil {
// couldn't find relative path from ancestor?
panic(err)
}
paths = append(paths, relPath)
}
return nil
})
return paths
}
func run() error {
if rawCommand == "" {
usageViolation("-c <commandToRun> is required and must be non-empty")
}
if sandboxesRoot == "" {
// In practice, the value of sandboxesRoot will mostly likely be at a fixed location relative to OUT_DIR,
// and the sbox executable will most likely be at a fixed location relative to OUT_DIR too, so
// the value of sandboxesRoot will most likely be at a fixed location relative to the sbox executable
// However, Soong also needs to be able to separately remove the sandbox directory on startup (if it has anything left in it)
// and by passing it as a parameter we don't need to duplicate its value
usageViolation("--sandbox-path <sandboxPath> is required and must be non-empty")
}
if len(outputRoot) == 0 {
usageViolation("--output-root <outputRoot> is required and must be non-empty")
}
// the contents of the __SBOX_OUT_FILES__ variable
outputsVarEntries := flag.Args()
if len(outputsVarEntries) == 0 {
usageViolation("at least one output file must be given")
}
// all outputs
var allOutputs []string
// setup directories
err := os.MkdirAll(sandboxesRoot, 0777)
if err != nil {
return err
}
err = os.RemoveAll(outputRoot)
if err != nil {
return err
}
err = os.MkdirAll(outputRoot, 0777)
if err != nil {
return err
}
tempDir, err := ioutil.TempDir(sandboxesRoot, "sbox")
for i, filePath := range outputsVarEntries {
if !strings.HasPrefix(filePath, "__SBOX_OUT_DIR__/") {
return fmt.Errorf("output files must start with `__SBOX_OUT_DIR__/`")
}
outputsVarEntries[i] = strings.TrimPrefix(filePath, "__SBOX_OUT_DIR__/")
}
allOutputs = append([]string(nil), outputsVarEntries...)
if depfileOut != "" {
sandboxedDepfile, err := filepath.Rel(outputRoot, depfileOut)
if err != nil {
return err
}
allOutputs = append(allOutputs, sandboxedDepfile)
if !strings.Contains(rawCommand, "__SBOX_DEPFILE__") {
return fmt.Errorf("the --depfile-out argument only makes sense if the command contains the text __SBOX_DEPFILE__")
}
rawCommand = strings.Replace(rawCommand, "__SBOX_DEPFILE__", filepath.Join(tempDir, sandboxedDepfile), -1)
}
if err != nil {
return fmt.Errorf("Failed to create temp dir: %s", err)
}
// In the common case, the following line of code is what removes the sandbox
// If a fatal error occurs (such as if our Go process is killed unexpectedly),
// then at the beginning of the next build, Soong will retry the cleanup
defer func() {
// in some cases we decline to remove the temp dir, to facilitate debugging
if !keepOutDir {
os.RemoveAll(tempDir)
}
}()
if strings.Contains(rawCommand, "__SBOX_OUT_DIR__") {
rawCommand = strings.Replace(rawCommand, "__SBOX_OUT_DIR__", tempDir, -1)
}
if strings.Contains(rawCommand, "__SBOX_OUT_FILES__") {
// expands into a space-separated list of output files to be generated into the sandbox directory
tempOutPaths := []string{}
for _, outputPath := range outputsVarEntries {
tempOutPath := path.Join(tempDir, outputPath)
tempOutPaths = append(tempOutPaths, tempOutPath)
}
pathsText := strings.Join(tempOutPaths, " ")
rawCommand = strings.Replace(rawCommand, "__SBOX_OUT_FILES__", pathsText, -1)
}
for _, filePath := range allOutputs {
dir := path.Join(tempDir, filepath.Dir(filePath))
err = os.MkdirAll(dir, 0777)
if err != nil {
return err
}
}
commandDescription := rawCommand
cmd := exec.Command("bash", "-c", rawCommand)
cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
err = cmd.Run()
if exit, ok := err.(*exec.ExitError); ok && !exit.Success() {
return fmt.Errorf("sbox command (%s) failed with err %#v\n", commandDescription, err.Error())
} else if err != nil {
return err
}
// validate that all files are created properly
var missingOutputErrors []string
for _, filePath := range allOutputs {
tempPath := filepath.Join(tempDir, filePath)
fileInfo, err := os.Stat(tempPath)
if err != nil {
missingOutputErrors = append(missingOutputErrors, fmt.Sprintf("%s: does not exist", filePath))
continue
}
if fileInfo.IsDir() {
missingOutputErrors = append(missingOutputErrors, fmt.Sprintf("%s: not a file", filePath))
}
}
if len(missingOutputErrors) > 0 {
// find all created files for making a more informative error message
createdFiles := findAllFilesUnder(tempDir)
// build error message
errorMessage := "mismatch between declared and actual outputs\n"
errorMessage += "in sbox command(" + commandDescription + ")\n\n"
errorMessage += "in sandbox " + tempDir + ",\n"
errorMessage += fmt.Sprintf("failed to create %v files:\n", len(missingOutputErrors))
for _, missingOutputError := range missingOutputErrors {
errorMessage += " " + missingOutputError + "\n"
}
if len(createdFiles) < 1 {
errorMessage += "created 0 files."
} else {
errorMessage += fmt.Sprintf("did create %v files:\n", len(createdFiles))
creationMessages := createdFiles
maxNumCreationLines := 10
if len(creationMessages) > maxNumCreationLines {
creationMessages = creationMessages[:maxNumCreationLines]
creationMessages = append(creationMessages, fmt.Sprintf("...%v more", len(createdFiles)-maxNumCreationLines))
}
for _, creationMessage := range creationMessages {
errorMessage += " " + creationMessage + "\n"
}
}
// Keep the temporary output directory around in case a user wants to inspect it for debugging purposes.
// Soong will delete it later anyway.
keepOutDir = true
return errors.New(errorMessage)
}
// the created files match the declared files; now move them
for _, filePath := range allOutputs {
tempPath := filepath.Join(tempDir, filePath)
destPath := filePath
if len(outputRoot) != 0 {
destPath = filepath.Join(outputRoot, filePath)
}
err := os.MkdirAll(filepath.Dir(destPath), 0777)
if err != nil {
return err
}
err = os.Rename(tempPath, destPath)
if err != nil {
return err
}
}
// TODO(jeffrygaston) if a process creates more output files than it declares, should there be a warning?
return nil
}