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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
commit47ab3d4a42e9ab51c465c4322d2ec233f6324e6b (patch)
treea61a0ffd83f4a3def4b36e5c8e99630c559aa723 /src/runtime/testdata/testprogcgo/eintr.go
parentInitial commit. (diff)
downloadgolang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.tar.xz
golang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.zip
Adding upstream version 1.18.10.upstream/1.18.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/testdata/testprogcgo/eintr.go')
-rw-r--r--src/runtime/testdata/testprogcgo/eintr.go246
1 files changed, 246 insertions, 0 deletions
diff --git a/src/runtime/testdata/testprogcgo/eintr.go b/src/runtime/testdata/testprogcgo/eintr.go
new file mode 100644
index 0000000..b35b280
--- /dev/null
+++ b/src/runtime/testdata/testprogcgo/eintr.go
@@ -0,0 +1,246 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9 && !windows
+// +build !plan9,!windows
+
+package main
+
+/*
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+
+static int clearRestart(int sig) {
+ struct sigaction sa;
+
+ memset(&sa, 0, sizeof sa);
+ if (sigaction(sig, NULL, &sa) < 0) {
+ return errno;
+ }
+ sa.sa_flags &=~ SA_RESTART;
+ if (sigaction(sig, &sa, NULL) < 0) {
+ return errno;
+ }
+ return 0;
+}
+*/
+import "C"
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "log"
+ "net"
+ "os"
+ "os/exec"
+ "sync"
+ "syscall"
+ "time"
+)
+
+func init() {
+ register("EINTR", EINTR)
+ register("Block", Block)
+}
+
+// Test various operations when a signal handler is installed without
+// the SA_RESTART flag. This tests that the os and net APIs handle EINTR.
+func EINTR() {
+ if errno := C.clearRestart(C.int(syscall.SIGURG)); errno != 0 {
+ log.Fatal(syscall.Errno(errno))
+ }
+ if errno := C.clearRestart(C.int(syscall.SIGWINCH)); errno != 0 {
+ log.Fatal(syscall.Errno(errno))
+ }
+ if errno := C.clearRestart(C.int(syscall.SIGCHLD)); errno != 0 {
+ log.Fatal(syscall.Errno(errno))
+ }
+
+ var wg sync.WaitGroup
+ testPipe(&wg)
+ testNet(&wg)
+ testExec(&wg)
+ wg.Wait()
+ fmt.Println("OK")
+}
+
+// spin does CPU bound spinning and allocating for a millisecond,
+// to get a SIGURG.
+//go:noinline
+func spin() (float64, []byte) {
+ stop := time.Now().Add(time.Millisecond)
+ r1 := 0.0
+ r2 := make([]byte, 200)
+ for time.Now().Before(stop) {
+ for i := 1; i < 1e6; i++ {
+ r1 += r1 / float64(i)
+ r2 = append(r2, bytes.Repeat([]byte{byte(i)}, 100)...)
+ r2 = r2[100:]
+ }
+ }
+ return r1, r2
+}
+
+// winch sends a few SIGWINCH signals to the process.
+func winch() {
+ ticker := time.NewTicker(100 * time.Microsecond)
+ defer ticker.Stop()
+ pid := syscall.Getpid()
+ for n := 10; n > 0; n-- {
+ syscall.Kill(pid, syscall.SIGWINCH)
+ <-ticker.C
+ }
+}
+
+// sendSomeSignals triggers a few SIGURG and SIGWINCH signals.
+func sendSomeSignals() {
+ done := make(chan struct{})
+ go func() {
+ spin()
+ close(done)
+ }()
+ winch()
+ <-done
+}
+
+// testPipe tests pipe operations.
+func testPipe(wg *sync.WaitGroup) {
+ r, w, err := os.Pipe()
+ if err != nil {
+ log.Fatal(err)
+ }
+ if err := syscall.SetNonblock(int(r.Fd()), false); err != nil {
+ log.Fatal(err)
+ }
+ if err := syscall.SetNonblock(int(w.Fd()), false); err != nil {
+ log.Fatal(err)
+ }
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ defer w.Close()
+ // Spin before calling Write so that the first ReadFull
+ // in the other goroutine will likely be interrupted
+ // by a signal.
+ sendSomeSignals()
+ // This Write will likely be interrupted by a signal
+ // as the other goroutine spins in the middle of reading.
+ // We write enough data that we should always fill the
+ // pipe buffer and need multiple write system calls.
+ if _, err := w.Write(bytes.Repeat([]byte{0}, 2<<20)); err != nil {
+ log.Fatal(err)
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ defer r.Close()
+ b := make([]byte, 1<<20)
+ // This ReadFull will likely be interrupted by a signal,
+ // as the other goroutine spins before writing anything.
+ if _, err := io.ReadFull(r, b); err != nil {
+ log.Fatal(err)
+ }
+ // Spin after reading half the data so that the Write
+ // in the other goroutine will likely be interrupted
+ // before it completes.
+ sendSomeSignals()
+ if _, err := io.ReadFull(r, b); err != nil {
+ log.Fatal(err)
+ }
+ }()
+}
+
+// testNet tests network operations.
+func testNet(wg *sync.WaitGroup) {
+ ln, err := net.Listen("tcp4", "127.0.0.1:0")
+ if err != nil {
+ if errors.Is(err, syscall.EAFNOSUPPORT) || errors.Is(err, syscall.EPROTONOSUPPORT) {
+ return
+ }
+ log.Fatal(err)
+ }
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ defer ln.Close()
+ c, err := ln.Accept()
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer c.Close()
+ cf, err := c.(*net.TCPConn).File()
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer cf.Close()
+ if err := syscall.SetNonblock(int(cf.Fd()), false); err != nil {
+ log.Fatal(err)
+ }
+ // See comments in testPipe.
+ sendSomeSignals()
+ if _, err := cf.Write(bytes.Repeat([]byte{0}, 2<<20)); err != nil {
+ log.Fatal(err)
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ sendSomeSignals()
+ c, err := net.Dial("tcp", ln.Addr().String())
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer c.Close()
+ cf, err := c.(*net.TCPConn).File()
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer cf.Close()
+ if err := syscall.SetNonblock(int(cf.Fd()), false); err != nil {
+ log.Fatal(err)
+ }
+ // See comments in testPipe.
+ b := make([]byte, 1<<20)
+ if _, err := io.ReadFull(cf, b); err != nil {
+ log.Fatal(err)
+ }
+ sendSomeSignals()
+ if _, err := io.ReadFull(cf, b); err != nil {
+ log.Fatal(err)
+ }
+ }()
+}
+
+func testExec(wg *sync.WaitGroup) {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ cmd := exec.Command(os.Args[0], "Block")
+ stdin, err := cmd.StdinPipe()
+ if err != nil {
+ log.Fatal(err)
+ }
+ cmd.Stderr = new(bytes.Buffer)
+ cmd.Stdout = cmd.Stderr
+ if err := cmd.Start(); err != nil {
+ log.Fatal(err)
+ }
+
+ go func() {
+ sendSomeSignals()
+ stdin.Close()
+ }()
+
+ if err := cmd.Wait(); err != nil {
+ log.Fatalf("%v:\n%s", err, cmd.Stdout)
+ }
+ }()
+}
+
+// Block blocks until stdin is closed.
+func Block() {
+ io.Copy(io.Discard, os.Stdin)
+}