From ccd9a55609fcc8814146a7c61898b47e3a7aea7d Mon Sep 17 00:00:00 2001 From: Mikio Hara Date: Sat, 11 Jun 2016 19:36:17 +0900 Subject: [PATCH] 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_unimp.go | 2 +- src/os/{wait_linux.go => wait_waitid.go} | 9 +++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) rename src/os/{wait_linux.go => wait_waitid.go} (71%) diff --git a/src/os/wait_unimp.go b/src/os/wait_unimp.go index 802b032c6ebc5..254bf7ec177c7 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_linux.go b/src/os/wait_waitid.go similarity index 71% rename from src/os/wait_linux.go rename to src/os/wait_waitid.go index 7707539630988..5dbd7f9766298 100644 --- a/src/os/wait_linux.go +++ b/src/os/wait_waitid.go @@ -2,6 +2,8 @@ // 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 ( @@ -16,8 +18,11 @@ const _P_PID = 1 // 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. + // 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)