ui/build/proc_sync_test.go - LeafOS-Project/android_build_soong - Gitiles

 // 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 build

 import (
 	"fmt"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"syscall"
 	"testing"

 	"android/soong/ui/logger"
 )

 // some util methods and data structures that aren't directly part of a test
 func makeLockDir() (path string, err error) {
 	return ioutil.TempDir("", "soong_lock_test")
 }
 func lockOrFail(t *testing.T) (lock fileLock) {
 	lockDir, err := makeLockDir()
 	var lockPointer *fileLock
 	if err == nil {
 		lockPointer, err = newLock(lockDir)
 	}
 	if err != nil {
 		os.RemoveAll(lockDir)
 		t.Fatalf("Failed to create lock: %v", err)
 	}

 	return *lockPointer
 }
 func removeTestLock(fileLock fileLock) {
 	lockdir := filepath.Dir(fileLock.File.Name())
 	os.RemoveAll(lockdir)
 }

 // countWaiter only exists for the purposes of testing lockSynchronous
 type countWaiter struct {
 	numWaitsElapsed int
 	maxNumWaits     int
 }

 func newCountWaiter(count int) (waiter *countWaiter) {
 	return &countWaiter{0, count}
 }

 func (c *countWaiter) wait() {
 	c.numWaitsElapsed++
 }
 func (c *countWaiter) checkDeadline() (done bool, remainder string) {
 	numWaitsRemaining := c.maxNumWaits - c.numWaitsElapsed
 	if numWaitsRemaining < 1 {
 		return true, ""
 	}
 	return false, fmt.Sprintf("%v waits remain", numWaitsRemaining)
 }
 func (c countWaiter) summarize() (summary string) {
 	return fmt.Sprintf("waiting %v times", c.maxNumWaits)
 }

 // countLock only exists for the purposes of testing lockSynchronous
 type countLock struct {
 	nextIndex    int
 	successIndex int
 }

 var _ lockable = (*countLock)(nil)

 // returns a countLock that succeeds on iteration <index>
 func testLockCountingTo(index int) (lock *countLock) {
 	return &countLock{nextIndex: 0, successIndex: index}
 }
 func (c *countLock) description() (message string) {
 	return fmt.Sprintf("counter that counts from %v to %v", c.nextIndex, c.successIndex)
 }
 func (c *countLock) tryLock() (err error) {
 	currentIndex := c.nextIndex
 	c.nextIndex++
 	if currentIndex == c.successIndex {
 		return nil
 	}
 	return fmt.Errorf("Lock busy: %s", c.description())
 }
 func (c *countLock) Unlock() (err error) {
 	if c.nextIndex == c.successIndex {
 		return nil
 	}
 	return fmt.Errorf("Not locked: %s", c.description())
 }

 // end of util methods

 // start of tests

 // simple test
 func TestGetLock(t *testing.T) {
 	lockfile := lockOrFail(t)
 	defer removeTestLock(lockfile)
 }

 // a more complicated test that spans multiple processes
 var lockPathVariable = "LOCK_PATH"
 var successStatus = 0
 var unexpectedError = 1
 var busyStatus = 2

 func TestTrylock(t *testing.T) {
 	lockpath := os.Getenv(lockPathVariable)
 	if len(lockpath) < 1 {
 		checkTrylockMainProcess(t)
 	} else {
 		getLockAndExit(lockpath)
 	}
 }

 // the portion of TestTrylock that runs in the main process
 func checkTrylockMainProcess(t *testing.T) {
 	var err error
 	lockfile := lockOrFail(t)
 	defer removeTestLock(lockfile)
 	lockdir := filepath.Dir(lockfile.File.Name())
 	otherAcquired, message, err := forkAndGetLock(lockdir)
 	if err != nil {
 		t.Fatalf("Unexpected error in subprocess trying to lock uncontested fileLock: %v. Subprocess output: %q", err, message)
 	}
 	if !otherAcquired {
 		t.Fatalf("Subprocess failed to lock uncontested fileLock. Subprocess output: %q", message)
 	}

 	err = lockfile.tryLock()
 	if err != nil {
 		t.Fatalf("Failed to lock fileLock: %v", err)
 	}

 	reacquired, message, err := forkAndGetLock(filepath.Dir(lockfile.File.Name()))
 	if err != nil {
 		t.Fatal(err)
 	}
 	if reacquired {
 		t.Fatalf("Permitted locking fileLock twice. Subprocess output: %q", message)
 	}

 	err = lockfile.Unlock()
 	if err != nil {
 		t.Fatalf("Error unlocking fileLock: %v", err)
 	}

 	reacquired, message, err = forkAndGetLock(filepath.Dir(lockfile.File.Name()))
 	if err != nil {
 		t.Fatal(err)
 	}
 	if !reacquired {
 		t.Fatalf("Subprocess failed to acquire lock after it was released by the main process. Subprocess output: %q", message)
 	}
 }
 func forkAndGetLock(lockDir string) (acquired bool, subprocessOutput []byte, err error) {
 	cmd := exec.Command(os.Args[0], "-test.run=TestTrylock")
 	cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%s", lockPathVariable, lockDir))
 	subprocessOutput, err = cmd.CombinedOutput()
 	exitStatus := successStatus
 	if exitError, ok := err.(*exec.ExitError); ok {
 		if waitStatus, ok := exitError.Sys().(syscall.WaitStatus); ok {
 			exitStatus = waitStatus.ExitStatus()
 		}
 	}
 	if exitStatus == successStatus {
 		return true, subprocessOutput, nil
 	} else if exitStatus == busyStatus {
 		return false, subprocessOutput, nil
 	} else {
 		return false, subprocessOutput, fmt.Errorf("Unexpected status %v", exitStatus)
 	}
 }

 // This function runs in a different process. See TestTrylock
 func getLockAndExit(lockpath string) {
 	fmt.Printf("Will lock path %q\n", lockpath)
 	lockfile, err := newLock(lockpath)
 	exitStatus := unexpectedError
 	if err == nil {
 		err = lockfile.tryLock()
 		if err == nil {
 			exitStatus = successStatus
 		} else {
 			exitStatus = busyStatus
 		}
 	}
 	fmt.Printf("Tried to lock path %s. Received error %v. Exiting with status %v\n", lockpath, err, exitStatus)
 	os.Exit(exitStatus)
 }

 func TestLockFirstTrySucceeds(t *testing.T) {
 	noopLogger := logger.New(ioutil.Discard)
 	lock := testLockCountingTo(0)
 	waiter := newCountWaiter(0)
 	err := lockSynchronous(lock, waiter, noopLogger)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if waiter.numWaitsElapsed != 0 {
 		t.Fatalf("Incorrect number of waits elapsed; expected 0, got %v", waiter.numWaitsElapsed)
 	}
 }
 func TestLockThirdTrySucceeds(t *testing.T) {
 	noopLogger := logger.New(ioutil.Discard)
 	lock := testLockCountingTo(2)
 	waiter := newCountWaiter(2)
 	err := lockSynchronous(lock, waiter, noopLogger)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if waiter.numWaitsElapsed != 2 {
 		t.Fatalf("Incorrect number of waits elapsed; expected 2, got %v", waiter.numWaitsElapsed)
 	}
 }
 func TestLockTimedOut(t *testing.T) {
 	noopLogger := logger.New(ioutil.Discard)
 	lock := testLockCountingTo(3)
 	waiter := newCountWaiter(2)
 	err := lockSynchronous(lock, waiter, noopLogger)
 	if err == nil {
 		t.Fatalf("Appeared to have acquired lock on iteration %v which should not be available until iteration %v", waiter.numWaitsElapsed, lock.successIndex)
 	}
 	if waiter.numWaitsElapsed != waiter.maxNumWaits {
 		t.Fatalf("Waited an incorrect number of times; expected %v, got %v", waiter.maxNumWaits, waiter.numWaitsElapsed)
 	}
 }
	// 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 build

	import (
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"syscall"
	"testing"

	"android/soong/ui/logger"
	)

	// some util methods and data structures that aren't directly part of a test
	func makeLockDir() (path string, err error) {
	return ioutil.TempDir("", "soong_lock_test")
	}
	func lockOrFail(t *testing.T) (lock fileLock) {
	lockDir, err := makeLockDir()
	var lockPointer *fileLock
	if err == nil {
	lockPointer, err = newLock(lockDir)
	}
	if err != nil {
	os.RemoveAll(lockDir)
	t.Fatalf("Failed to create lock: %v", err)
	}

	return *lockPointer
	}
	func removeTestLock(fileLock fileLock) {
	lockdir := filepath.Dir(fileLock.File.Name())
	os.RemoveAll(lockdir)
	}

	// countWaiter only exists for the purposes of testing lockSynchronous
	type countWaiter struct {
	numWaitsElapsed int
	maxNumWaits int
	}

	func newCountWaiter(count int) (waiter *countWaiter) {
	return &countWaiter{0, count}
	}

	func (c *countWaiter) wait() {
	c.numWaitsElapsed++
	}
	func (c *countWaiter) checkDeadline() (done bool, remainder string) {
	numWaitsRemaining := c.maxNumWaits - c.numWaitsElapsed
	if numWaitsRemaining < 1 {
	return true, ""
	}
	return false, fmt.Sprintf("%v waits remain", numWaitsRemaining)
	}
	func (c countWaiter) summarize() (summary string) {
	return fmt.Sprintf("waiting %v times", c.maxNumWaits)
	}

	// countLock only exists for the purposes of testing lockSynchronous
	type countLock struct {
	nextIndex int
	successIndex int
	}

	var _ lockable = (*countLock)(nil)

	// returns a countLock that succeeds on iteration <index>
	func testLockCountingTo(index int) (lock *countLock) {
	return &countLock{nextIndex: 0, successIndex: index}
	}
	func (c *countLock) description() (message string) {
	return fmt.Sprintf("counter that counts from %v to %v", c.nextIndex, c.successIndex)
	}
	func (c *countLock) tryLock() (err error) {
	currentIndex := c.nextIndex
	c.nextIndex++
	if currentIndex == c.successIndex {
	return nil
	}
	return fmt.Errorf("Lock busy: %s", c.description())
	}
	func (c *countLock) Unlock() (err error) {
	if c.nextIndex == c.successIndex {
	return nil
	}
	return fmt.Errorf("Not locked: %s", c.description())
	}

	// end of util methods

	// start of tests

	// simple test
	func TestGetLock(t *testing.T) {
	lockfile := lockOrFail(t)
	defer removeTestLock(lockfile)
	}

	// a more complicated test that spans multiple processes
	var lockPathVariable = "LOCK_PATH"
	var successStatus = 0
	var unexpectedError = 1
	var busyStatus = 2

	func TestTrylock(t *testing.T) {
	lockpath := os.Getenv(lockPathVariable)
	if len(lockpath) < 1 {
	checkTrylockMainProcess(t)
	} else {
	getLockAndExit(lockpath)
	}
	}

	// the portion of TestTrylock that runs in the main process
	func checkTrylockMainProcess(t *testing.T) {
	var err error
	lockfile := lockOrFail(t)
	defer removeTestLock(lockfile)
	lockdir := filepath.Dir(lockfile.File.Name())
	otherAcquired, message, err := forkAndGetLock(lockdir)
	if err != nil {
	t.Fatalf("Unexpected error in subprocess trying to lock uncontested fileLock: %v. Subprocess output: %q", err, message)
	}
	if !otherAcquired {
	t.Fatalf("Subprocess failed to lock uncontested fileLock. Subprocess output: %q", message)
	}

	err = lockfile.tryLock()
	if err != nil {
	t.Fatalf("Failed to lock fileLock: %v", err)
	}

	reacquired, message, err := forkAndGetLock(filepath.Dir(lockfile.File.Name()))
	if err != nil {
	t.Fatal(err)
	}
	if reacquired {
	t.Fatalf("Permitted locking fileLock twice. Subprocess output: %q", message)
	}

	err = lockfile.Unlock()
	if err != nil {
	t.Fatalf("Error unlocking fileLock: %v", err)
	}

	reacquired, message, err = forkAndGetLock(filepath.Dir(lockfile.File.Name()))
	if err != nil {
	t.Fatal(err)
	}
	if !reacquired {
	t.Fatalf("Subprocess failed to acquire lock after it was released by the main process. Subprocess output: %q", message)
	}
	}
	func forkAndGetLock(lockDir string) (acquired bool, subprocessOutput []byte, err error) {
	cmd := exec.Command(os.Args[0], "-test.run=TestTrylock")
	cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%s", lockPathVariable, lockDir))
	subprocessOutput, err = cmd.CombinedOutput()
	exitStatus := successStatus
	if exitError, ok := err.(*exec.ExitError); ok {
	if waitStatus, ok := exitError.Sys().(syscall.WaitStatus); ok {
	exitStatus = waitStatus.ExitStatus()
	}
	}
	if exitStatus == successStatus {
	return true, subprocessOutput, nil
	} else if exitStatus == busyStatus {
	return false, subprocessOutput, nil
	} else {
	return false, subprocessOutput, fmt.Errorf("Unexpected status %v", exitStatus)
	}
	}

	// This function runs in a different process. See TestTrylock
	func getLockAndExit(lockpath string) {
	fmt.Printf("Will lock path %q\n", lockpath)
	lockfile, err := newLock(lockpath)
	exitStatus := unexpectedError
	if err == nil {
	err = lockfile.tryLock()
	if err == nil {
	exitStatus = successStatus
	} else {
	exitStatus = busyStatus
	}
	}
	fmt.Printf("Tried to lock path %s. Received error %v. Exiting with status %v\n", lockpath, err, exitStatus)
	os.Exit(exitStatus)
	}

	func TestLockFirstTrySucceeds(t *testing.T) {
	noopLogger := logger.New(ioutil.Discard)
	lock := testLockCountingTo(0)
	waiter := newCountWaiter(0)
	err := lockSynchronous(lock, waiter, noopLogger)
	if err != nil {
	t.Fatal(err)
	}
	if waiter.numWaitsElapsed != 0 {
	t.Fatalf("Incorrect number of waits elapsed; expected 0, got %v", waiter.numWaitsElapsed)
	}
	}
	func TestLockThirdTrySucceeds(t *testing.T) {
	noopLogger := logger.New(ioutil.Discard)
	lock := testLockCountingTo(2)
	waiter := newCountWaiter(2)
	err := lockSynchronous(lock, waiter, noopLogger)
	if err != nil {
	t.Fatal(err)
	}
	if waiter.numWaitsElapsed != 2 {
	t.Fatalf("Incorrect number of waits elapsed; expected 2, got %v", waiter.numWaitsElapsed)
	}
	}
	func TestLockTimedOut(t *testing.T) {
	noopLogger := logger.New(ioutil.Discard)
	lock := testLockCountingTo(3)
	waiter := newCountWaiter(2)
	err := lockSynchronous(lock, waiter, noopLogger)
	if err == nil {
	t.Fatalf("Appeared to have acquired lock on iteration %v which should not be available until iteration %v", waiter.numWaitsElapsed, lock.successIndex)
	}
	if waiter.numWaitsElapsed != waiter.maxNumWaits {
	t.Fatalf("Waited an incorrect number of times; expected %v, got %v", waiter.maxNumWaits, waiter.numWaitsElapsed)
	}
	}