unix: add Readv, Writev, Preadv, Pwritev for OpenBSD

Add OpenBSD libc syscall wrappers for vectored I/O, and share the
existing Darwin wrapper implementation and tests.

Fixes golang/go#78049

Change-Id: Ie2743ef36a5cb73b05cc551c9c1108503f5992b6
Reviewed-on: https://go-review.googlesource.com/c/sys/+/771300
LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
This commit is contained in:
Aaqa Ishtyaq
2026-05-12 12:53:07 -07:00
committed by Gopher Robot
parent fb1facd76f
commit 04396e85d4
18 changed files with 968 additions and 89 deletions
-89
View File
@@ -602,95 +602,6 @@ func Connectx(fd int, srcIf uint32, srcAddr, dstAddr Sockaddr, associd SaeAssocI
return
}
const minIovec = 8
func Readv(fd int, iovs [][]byte) (n int, err error) {
iovecs := make([]Iovec, 0, minIovec)
iovecs = appendBytes(iovecs, iovs)
n, err = readv(fd, iovecs)
readvRacedetect(iovecs, n, err)
return n, err
}
func Preadv(fd int, iovs [][]byte, offset int64) (n int, err error) {
iovecs := make([]Iovec, 0, minIovec)
iovecs = appendBytes(iovecs, iovs)
n, err = preadv(fd, iovecs, offset)
readvRacedetect(iovecs, n, err)
return n, err
}
func Writev(fd int, iovs [][]byte) (n int, err error) {
iovecs := make([]Iovec, 0, minIovec)
iovecs = appendBytes(iovecs, iovs)
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
n, err = writev(fd, iovecs)
writevRacedetect(iovecs, n)
return n, err
}
func Pwritev(fd int, iovs [][]byte, offset int64) (n int, err error) {
iovecs := make([]Iovec, 0, minIovec)
iovecs = appendBytes(iovecs, iovs)
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
n, err = pwritev(fd, iovecs, offset)
writevRacedetect(iovecs, n)
return n, err
}
func appendBytes(vecs []Iovec, bs [][]byte) []Iovec {
for _, b := range bs {
var v Iovec
v.SetLen(len(b))
if len(b) > 0 {
v.Base = &b[0]
} else {
v.Base = (*byte)(unsafe.Pointer(&_zero))
}
vecs = append(vecs, v)
}
return vecs
}
func writevRacedetect(iovecs []Iovec, n int) {
if !raceenabled {
return
}
for i := 0; n > 0 && i < len(iovecs); i++ {
m := int(iovecs[i].Len)
if m > n {
m = n
}
n -= m
if m > 0 {
raceReadRange(unsafe.Pointer(iovecs[i].Base), m)
}
}
}
func readvRacedetect(iovecs []Iovec, n int, err error) {
if !raceenabled {
return
}
for i := 0; n > 0 && i < len(iovecs); i++ {
m := int(iovecs[i].Len)
if m > n {
m = n
}
n -= m
if m > 0 {
raceWriteRange(unsafe.Pointer(iovecs[i].Base), m)
}
}
if err == nil {
raceAcquire(unsafe.Pointer(&ioSync))
}
}
//sys connectx(fd int, endpoints *SaEndpoints, associd SaeAssocID, flags uint32, iov []Iovec, n *uintptr, connid *SaeConnID) (err error)
//sys sendfile(infd int, outfd int, offset int64, len *int64, hdtr unsafe.Pointer, flags int) (err error)