runsc: move test_app in a separate directory

Opensource tools (e. g. https://github.com/fatih/vim-go) can't hanlde more than
one golang package in one directory.

PiperOrigin-RevId: 246435962
Change-Id: I67487915e3838762424b2d168efc54ae34fb801f

2 files changed, 302 insertions, 0 deletions

diff --git a/runsc/container/test_app/BUILD b/runsc/container/test_app/BUILD
new file mode 100644
index 000000000..054705ed7
--- /dev/null
+++ b/runsc/container/test_app/BUILD
@@ -0,0 +1,15 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_binary")
+
+package(licenses = ["notice"])
+
+go_binary(
+    name = "test_app",
+    testonly = 1,
+    srcs = ["test_app.go"],
+    pure = "on",
+    visibility = ["//runsc/container:__pkg__"],
+    deps = [
+        "//runsc/test/testutil",
+        "@com_github_google_subcommands//:go_default_library",
+    ],
+)
diff --git a/runsc/container/test_app/test_app.go b/runsc/container/test_app/test_app.go
new file mode 100644
index 000000000..62923f1ef
--- /dev/null
+++ b/runsc/container/test_app/test_app.go
@@ -0,0 +1,287 @@
+// Copyright 2018 The gVisor Authors.
+//
+// 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.
+
+// Binary test_app is like a swiss knife for tests that need to run anything
+// inside the sandbox. New functionality can be added with new commands.
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net"
+	"os"
+	"os/exec"
+	"strconv"
+	sys "syscall"
+	"time"
+
+	"flag"
+	"github.com/google/subcommands"
+	"gvisor.googlesource.com/gvisor/runsc/test/testutil"
+)
+
+func main() {
+	subcommands.Register(subcommands.HelpCommand(), "")
+	subcommands.Register(subcommands.FlagsCommand(), "")
+	subcommands.Register(new(uds), "")
+	subcommands.Register(new(taskTree), "")
+	subcommands.Register(new(forkBomb), "")
+	subcommands.Register(new(reaper), "")
+	subcommands.Register(new(syscall), "")
+
+	flag.Parse()
+
+	exitCode := subcommands.Execute(context.Background())
+	os.Exit(int(exitCode))
+}
+
+type uds struct {
+	fileName   string
+	socketPath string
+}
+
+// Name implements subcommands.Command.Name.
+func (*uds) Name() string {
+	return "uds"
+}
+
+// Synopsis implements subcommands.Command.Synopsys.
+func (*uds) Synopsis() string {
+	return "creates unix domain socket client and server. Client sends a contant flow of sequential numbers. Server prints them to --file"
+}
+
+// Usage implements subcommands.Command.Usage.
+func (*uds) Usage() string {
+	return "uds <flags>"
+}
+
+// SetFlags implements subcommands.Command.SetFlags.
+func (c *uds) SetFlags(f *flag.FlagSet) {
+	f.StringVar(&c.fileName, "file", "", "name of output file")
+	f.StringVar(&c.socketPath, "socket", "", "path to socket")
+}
+
+// Execute implements subcommands.Command.Execute.
+func (c *uds) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
+	if c.fileName == "" || c.socketPath == "" {
+		log.Fatal("Flags cannot be empty, given: fileName: %q, socketPath: %q", c.fileName, c.socketPath)
+		return subcommands.ExitFailure
+	}
+	outputFile, err := os.OpenFile(c.fileName, os.O_WRONLY|os.O_CREATE, 0666)
+	if err != nil {
+		log.Fatal("error opening output file:", err)
+	}
+
+	defer os.Remove(c.socketPath)
+
+	listener, err := net.Listen("unix", c.socketPath)
+	if err != nil {
+		log.Fatal("error listening on socket %q:", c.socketPath, err)
+	}
+
+	go server(listener, outputFile)
+	for i := 0; ; i++ {
+		conn, err := net.Dial("unix", c.socketPath)
+		if err != nil {
+			log.Fatal("error dialing:", err)
+		}
+		if _, err := conn.Write([]byte(strconv.Itoa(i))); err != nil {
+			log.Fatal("error writing:", err)
+		}
+		conn.Close()
+		time.Sleep(100 * time.Millisecond)
+	}
+}
+
+func server(listener net.Listener, out *os.File) {
+	buf := make([]byte, 16)
+
+	for {
+		c, err := listener.Accept()
+		if err != nil {
+			log.Fatal("error accepting connection:", err)
+		}
+		nr, err := c.Read(buf)
+		if err != nil {
+			log.Fatal("error reading from buf:", err)
+		}
+		data := buf[0:nr]
+		fmt.Fprint(out, string(data)+"\n")
+	}
+}
+
+type taskTree struct {
+	depth int
+	width int
+	pause bool
+}
+
+// Name implements subcommands.Command.
+func (*taskTree) Name() string {
+	return "task-tree"
+}
+
+// Synopsis implements subcommands.Command.
+func (*taskTree) Synopsis() string {
+	return "creates a tree of tasks"
+}
+
+// Usage implements subcommands.Command.
+func (*taskTree) Usage() string {
+	return "task-tree <flags>"
+}
+
+// SetFlags implements subcommands.Command.
+func (c *taskTree) SetFlags(f *flag.FlagSet) {
+	f.IntVar(&c.depth, "depth", 1, "number of levels to create")
+	f.IntVar(&c.width, "width", 1, "number of tasks at each level")
+	f.BoolVar(&c.pause, "pause", false, "whether the tasks should pause perpetually")
+}
+
+// Execute implements subcommands.Command.
+func (c *taskTree) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
+	stop := testutil.StartReaper()
+	defer stop()
+
+	if c.depth == 0 {
+		log.Printf("Child sleeping, PID: %d\n", os.Getpid())
+		select {}
+	}
+	log.Printf("Parent %d sleeping, PID: %d\n", c.depth, os.Getpid())
+
+	var cmds []*exec.Cmd
+	for i := 0; i < c.width; i++ {
+		cmd := exec.Command(
+			"/proc/self/exe", c.Name(),
+			"--depth", strconv.Itoa(c.depth-1),
+			"--width", strconv.Itoa(c.width),
+			"--pause", strconv.FormatBool(c.pause))
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+
+		if err := cmd.Start(); err != nil {
+			log.Fatal("failed to call self:", err)
+		}
+		cmds = append(cmds, cmd)
+	}
+
+	for _, c := range cmds {
+		c.Wait()
+	}
+
+	if c.pause {
+		select {}
+	}
+
+	return subcommands.ExitSuccess
+}
+
+type forkBomb struct {
+	delay time.Duration
+}
+
+// Name implements subcommands.Command.
+func (*forkBomb) Name() string {
+	return "fork-bomb"
+}
+
+// Synopsis implements subcommands.Command.
+func (*forkBomb) Synopsis() string {
+	return "creates child process until the end of times"
+}
+
+// Usage implements subcommands.Command.
+func (*forkBomb) Usage() string {
+	return "fork-bomb <flags>"
+}
+
+// SetFlags implements subcommands.Command.
+func (c *forkBomb) SetFlags(f *flag.FlagSet) {
+	f.DurationVar(&c.delay, "delay", 100*time.Millisecond, "amount of time to delay creation of child")
+}
+
+// Execute implements subcommands.Command.
+func (c *forkBomb) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
+	time.Sleep(c.delay)
+
+	cmd := exec.Command("/proc/self/exe", c.Name())
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		log.Fatal("failed to call self:", err)
+	}
+	return subcommands.ExitSuccess
+}
+
+type reaper struct{}
+
+// Name implements subcommands.Command.
+func (*reaper) Name() string {
+	return "reaper"
+}
+
+// Synopsis implements subcommands.Command.
+func (*reaper) Synopsis() string {
+	return "reaps all children in a loop"
+}
+
+// Usage implements subcommands.Command.
+func (*reaper) Usage() string {
+	return "reaper <flags>"
+}
+
+// SetFlags implements subcommands.Command.
+func (*reaper) SetFlags(*flag.FlagSet) {}
+
+// Execute implements subcommands.Command.
+func (c *reaper) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
+	stop := testutil.StartReaper()
+	defer stop()
+	select {}
+}
+
+type syscall struct {
+	sysno uint64
+}
+
+// Name implements subcommands.Command.
+func (*syscall) Name() string {
+	return "syscall"
+}
+
+// Synopsis implements subcommands.Command.
+func (*syscall) Synopsis() string {
+	return "syscall makes a syscall"
+}
+
+// Usage implements subcommands.Command.
+func (*syscall) Usage() string {
+	return "syscall <flags>"
+}
+
+// SetFlags implements subcommands.Command.
+func (s *syscall) SetFlags(f *flag.FlagSet) {
+	f.Uint64Var(&s.sysno, "syscall", 0, "syscall to call")
+}
+
+// Execute implements subcommands.Command.
+func (s *syscall) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
+	if _, _, errno := sys.Syscall(uintptr(s.sysno), 0, 0, 0); errno != 0 {
+		fmt.Printf("syscall(%d, 0, 0...) failed: %v\n", s.sysno, errno)
+	} else {
+		fmt.Printf("syscall(%d, 0, 0...) success\n", s.sysno)
+	}
+	return subcommands.ExitSuccess
+}