From ccd9a55609fcc8814146a7c61898b47e3a7aea7d Mon Sep 17 00:00:00 2001 From: Mikio Hara Date: Sat, 11 Jun 2016 19:36:17 +0900 Subject: os: use waitid to avoid wait/kill race on darwin This change is a followup to https://go-review.googlesource.com/23967 for Darwin. Updates #13987. Updates #16028. Change-Id: Ib1fb9f957fafd0f91da6fceea56620e29ad82b00 Reviewed-on: https://go-review.googlesource.com/24020 Reviewed-by: Ian Lance Taylor --- src/os/wait_linux.go | 29 ----------------------------- src/os/wait_unimp.go | 2 +- src/os/wait_waitid.go | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 35 insertions(+), 30 deletions(-) delete mode 100644 src/os/wait_linux.go create mode 100644 src/os/wait_waitid.go diff --git a/src/os/wait_linux.go b/src/os/wait_linux.go deleted file mode 100644 index 7707539630..0000000000 --- a/src/os/wait_linux.go +++ /dev/null @@ -1,29 +0,0 @@ -// Copyright 2016 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. - -package os - -import ( - "runtime" - "syscall" - "unsafe" -) - -const _P_PID = 1 - -// blockUntilWaitable attempts to block until a call to p.Wait will -// succeed immediately, and returns whether it has done so. -// It does not actually call p.Wait. -func (p *Process) blockUntilWaitable() (bool, error) { - // waitid expects a pointer to a siginfo_t, which is 128 bytes - // on all systems. We don't care about the values it returns. - var siginfo [128]byte - psig := &siginfo[0] - _, _, e := syscall.Syscall6(syscall.SYS_WAITID, _P_PID, uintptr(p.Pid), uintptr(unsafe.Pointer(psig)), syscall.WEXITED|syscall.WNOWAIT, 0, 0) - runtime.KeepAlive(psig) - if e != 0 { - return false, NewSyscallError("waitid", e) - } - return true, nil -} diff --git a/src/os/wait_unimp.go b/src/os/wait_unimp.go index 802b032c6e..254bf7ec17 100644 --- a/src/os/wait_unimp.go +++ b/src/os/wait_unimp.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd nacl netbsd openbsd solaris +// +build dragonfly freebsd nacl netbsd openbsd solaris package os diff --git a/src/os/wait_waitid.go b/src/os/wait_waitid.go new file mode 100644 index 0000000000..5dbd7f9766 --- /dev/null +++ b/src/os/wait_waitid.go @@ -0,0 +1,34 @@ +// Copyright 2016 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. + +// +build darwin linux + +package os + +import ( + "runtime" + "syscall" + "unsafe" +) + +const _P_PID = 1 + +// blockUntilWaitable attempts to block until a call to p.Wait will +// succeed immediately, and returns whether it has done so. +// It does not actually call p.Wait. +func (p *Process) blockUntilWaitable() (bool, error) { + // The waitid system call expects a pointer to a siginfo_t, + // which is 128 bytes on all GNU/Linux systems. + // On Darwin, it requires greater than or equal to 64 bytes + // for darwin/{386,arm} and 104 bytes for darwin/amd64. + // We don't care about the values it returns. + var siginfo [128]byte + psig := &siginfo[0] + _, _, e := syscall.Syscall6(syscall.SYS_WAITID, _P_PID, uintptr(p.Pid), uintptr(unsafe.Pointer(psig)), syscall.WEXITED|syscall.WNOWAIT, 0, 0) + runtime.KeepAlive(psig) + if e != 0 { + return false, NewSyscallError("waitid", e) + } + return true, nil +} -- cgit v1.3