os, syscall: use wait6 to avoid wait/kill race on dragonfly

Follow CL 23967 and CL 24021 which did the same on linux and freebsd,
respectively.

Updates #13987
Updates #16028

Change-Id: Ia30ef8b5cffd8f9eb75c29ee5fe350dac2be6d44
Reviewed-on: https://go-review.googlesource.com/c/go/+/315279
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/os/wait_unimp.go b/src/os/wait_unimp.go
index 28dc2a5939fa9d56dc9c01b54b69abfebd606387..07b5b6b66b9c05afb14452168509d209c84f6b25 100644 (file)
--- a/src/os/wait_unimp.go
+++ b/src/os/wait_unimp.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || (js && wasm) || netbsd || openbsd || solaris
-// +build aix darwin dragonfly js,wasm netbsd openbsd solaris
+//go:build aix || darwin || (js && wasm) || netbsd || openbsd || solaris
+// +build aix darwin js,wasm netbsd openbsd solaris
 
 package os
 

diff --git a/src/os/wait_wait6.go b/src/os/wait_wait6.go
index 895f21069af2a1003b4a61e7bec7eeb2fd2f495f..51193401f938317d008f13d23d4c448f806b5050 100644 (file)
--- a/src/os/wait_wait6.go
+++ b/src/os/wait_wait6.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build freebsd
-// +build freebsd
+//go:build dragonfly || freebsd
+// +build dragonfly freebsd
 
 package os
 
@@ -23,9 +23,9 @@ func (p *Process) blockUntilWaitable() (bool, error) {
                // The arguments on 32-bit FreeBSD look like the following:
                // - freebsd32_wait6_args{ idtype, id1, id2, status, options, wrusage, info } or
                // - freebsd32_wait6_args{ idtype, pad, id1, id2, status, options, wrusage, info } when PAD64_REQUIRED=1 on ARM, MIPS or PowerPC
-               if runtime.GOARCH == "386" {
+               if runtime.GOOS == "freebsd" && runtime.GOARCH == "386" {
                        _, _, errno = syscall.Syscall9(syscall.SYS_WAIT6, _P_PID, uintptr(p.Pid), 0, 0, syscall.WEXITED|syscall.WNOWAIT, 0, 0, 0, 0)
-               } else if runtime.GOARCH == "arm" {
+               } else if runtime.GOOS == "freebsd" && runtime.GOARCH == "arm" {
                        _, _, errno = syscall.Syscall9(syscall.SYS_WAIT6, _P_PID, 0, uintptr(p.Pid), 0, 0, syscall.WEXITED|syscall.WNOWAIT, 0, 0, 0)
                } else {
                        _, _, errno = syscall.Syscall6(syscall.SYS_WAIT6, _P_PID, uintptr(p.Pid), 0, syscall.WEXITED|syscall.WNOWAIT, 0, 0)
@@ -35,7 +35,9 @@ func (p *Process) blockUntilWaitable() (bool, error) {
                }
        }
        runtime.KeepAlive(p)
-       if errno != 0 {
+       if errno == syscall.ENOSYS {
+               return false, nil
+       } else if errno != 0 {
                return false, NewSyscallError("wait6", errno)
        }
        return true, nil

diff --git a/src/syscall/zerrors_dragonfly_amd64.go b/src/syscall/zerrors_dragonfly_amd64.go
index 8ed611b3e4f2fa3a730c0dadaa7af9b6efb064ed..35e2a52d253b6daafc0d20c80a6603af74c5caed 100644 (file)
--- a/src/syscall/zerrors_dragonfly_amd64.go
+++ b/src/syscall/zerrors_dragonfly_amd64.go
@@ -1239,8 +1239,10 @@ const (
        VWERASE                           = 0x4
        WCONTINUED                        = 0x4
        WCOREFLAG                         = 0x80
+       WEXITED                           = 0x10
        WLINUXCLONE                       = 0x80000000
        WNOHANG                           = 0x1
+       WNOWAIT                           = 0x8
        WSTOPPED                          = 0x7f
        WUNTRACED                         = 0x2
 )

diff --git a/src/syscall/zsysnum_dragonfly_amd64.go b/src/syscall/zsysnum_dragonfly_amd64.go
index ae504a5f0c2658087dc21024fda991ddf2dd9958..e8996db0f8dd580f016d94d5c50e29d168a3e7ef 100644 (file)
--- a/src/syscall/zsysnum_dragonfly_amd64.go
+++ b/src/syscall/zsysnum_dragonfly_amd64.go
@@ -305,4 +305,5 @@ const (
        SYS_PIPE2                  = 538 // { int pipe2(int *fildes, int flags); }
        SYS_UTIMENSAT              = 539 // { int utimensat(int fd, const char *path, const struct timespec *ts, int flags); }
        SYS_ACCEPT4                = 541 // { int accept4(int s, caddr_t name, int *anamelen, int flags); }
+       SYS_WAIT6                  = 548 // { int wait6(idtype_t idtype, id_t id, int *status, int options, struct __wrusage *wrusage, siginfo_t *info); }
 )