unix: don't use deprecated syscalls on linux/arm64

On linux/arm64 we used to manually define syscall numbers for some
deprecated syscalls. Most of them are unused by now anyhow. Convert the
remaining syscall wrappers using them to implement the respective
functionality using a non-deprecated syscall (in the same way glibc does
it):

- Implement EpollCreate using EpollCreate1 and additionally check
  that the passed size argument is larger than 0.
- Implement Futimesat and utimes using utimensat. Also change futimesat
  on the other geese to take a string instead of *byte and let the
  generated wrapper do the BytePtrFromString conversion.
- Return ENOSYS from Ustat. The ustat syscall has been deprecated for a
  long time in favor of fstatfs and statfs. Even glibc will deprecate
  ustat in the upcoming 2.28 release [1].

[1] https://sourceware.org/git/?p=glibc.git;a=blob;f=NEWS;h=d51fa09544f03899b7ff5a80569db088c3c23c28;hb=HEAD#l90

Change-Id: I7ea38a3cd394b0875f17443b14e107fd9c70350d
Reviewed-on: https://go-review.googlesource.com/119655
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

unix/syscall_linux.go

@@ -148,8 +148,6 @@ func Unlink(path string) error {
 
 //sys	Unlinkat(dirfd int, path string, flags int) (err error)
 
-//sys	utimes(path string, times *[2]Timeval) (err error)
-
 func Utimes(path string, tv []Timeval) error {
 	if tv == nil {
 		err := utimensat(AT_FDCWD, path, nil, 0)
@@ -207,20 +205,14 @@ func UtimesNanoAt(dirfd int, path string, ts []Timespec, flags int) error {
 	return utimensat(dirfd, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), flags)
 }
 
-//sys	futimesat(dirfd int, path *byte, times *[2]Timeval) (err error)
-
 func Futimesat(dirfd int, path string, tv []Timeval) error {
-	pathp, err := BytePtrFromString(path)
-	if err != nil {
-		return err
-	}
 	if tv == nil {
-		return futimesat(dirfd, pathp, nil)
+		return futimesat(dirfd, path, nil)
 	}
 	if len(tv) != 2 {
 		return EINVAL
 	}
-	return futimesat(dirfd, pathp, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
+	return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
 }
 
 func Futimes(fd int, tv []Timeval) (err error) {
@@ -1221,7 +1213,6 @@ func Mount(source string, target string, fstype string, flags uintptr, data stri
 //sys	CopyFileRange(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error)
 //sys	Dup(oldfd int) (fd int, err error)
 //sys	Dup3(oldfd int, newfd int, flags int) (err error)
-//sysnb	EpollCreate(size int) (fd int, err error)
 //sysnb	EpollCreate1(flag int) (fd int, err error)
 //sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
 //sys	Eventfd(initval uint, flags int) (fd int, err error) = SYS_EVENTFD2
@@ -1306,7 +1297,6 @@ func Setgid(uid int) (err error) {
 //sysnb	Uname(buf *Utsname) (err error)
 //sys	Unmount(target string, flags int) (err error) = SYS_UMOUNT2
 //sys	Unshare(flags int) (err error)
-//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sys	write(fd int, p []byte) (n int, err error)
 //sys	exitThread(code int) (err error) = SYS_EXIT
 //sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ

unix/syscall_linux_386.go

@@ -50,6 +50,8 @@ func Pipe2(p []int, flags int) (err error) {
 // 64-bit file system and 32-bit uid calls
 // (386 default is 32-bit file system and 16-bit uid).
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
+//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64_64
 //sys	Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
@@ -77,12 +79,12 @@ func Pipe2(p []int, flags int) (err error) {
 //sys	Stat(path string, stat *Stat_t) (err error) = SYS_STAT64
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error) = SYS_TRUNCATE64
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sysnb	getgroups(n int, list *_Gid_t) (nn int, err error) = SYS_GETGROUPS32
 //sysnb	setgroups(n int, list *_Gid_t) (err error) = SYS_SETGROUPS32
 //sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) = SYS__NEWSELECT
 
 //sys	mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, err error)
-//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Pause() (err error)
 
 func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error) {
@@ -164,11 +166,11 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 	return newoffset, nil
 }
 
-// Vsyscalls on amd64.
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 //sysnb	Time(t *Time_t) (tt Time_t, err error)
-
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 // On x86 Linux, all the socket calls go through an extra indirection,
 // I think because the 5-register system call interface can't handle

unix/syscall_linux_amd64.go

@@ -7,6 +7,7 @@
 package unix
 
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
@@ -57,6 +58,7 @@ func Stat(path string, stat *Stat_t) (err error) {
 //sys	Statfs(path string, buf *Statfs_t) (err error)
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error)
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
 //sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
 //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
@@ -75,6 +77,8 @@ func Stat(path string, stat *Stat_t) (err error) {
 //sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
 //sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
+
 func Gettimeofday(tv *Timeval) (err error) {
 	errno := gettimeofday(tv)
 	if errno != 0 {
@@ -96,6 +100,7 @@ func Time(t *Time_t) (tt Time_t, err error) {
 }
 
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 func setTimespec(sec, nsec int64) Timespec {
 	return Timespec{Sec: sec, Nsec: nsec}

unix/syscall_linux_arm.go

@@ -75,6 +75,8 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 // 64-bit file system and 32-bit uid calls
 // (16-bit uid calls are not always supported in newer kernels)
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
+//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
 //sys	Fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
@@ -86,6 +88,7 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 //sys	Lchown(path string, uid int, gid int) (err error) = SYS_LCHOWN32
 //sys	Listen(s int, n int) (err error)
 //sys	Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64
+//sys	Pause() (err error)
 //sys	sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) = SYS_SENDFILE64
 //sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) = SYS__NEWSELECT
 //sys	Setfsgid(gid int) (err error) = SYS_SETFSGID32
@@ -97,11 +100,10 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
 //sys	Shutdown(fd int, how int) (err error)
 //sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error)
 //sys	Stat(path string, stat *Stat_t) (err error) = SYS_STAT64
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 
-// Vsyscalls on amd64.
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
-//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
-//sys	Pause() (err error)
 
 func Time(t *Time_t) (Time_t, error) {
 	var tv Timeval
@@ -123,6 +125,8 @@ func Utime(path string, buf *Utimbuf) error {
 	return Utimes(path, tv)
 }
 
+//sys	utimes(path string, times *[2]Timeval) (err error)
+
 //sys   Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64
 //sys   Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64
 //sys	Truncate(path string, length int64) (err error) = SYS_TRUNCATE64

unix/syscall_linux_arm64.go

@@ -6,6 +6,15 @@
 
 package unix
 
+import "unsafe"
+
+func EpollCreate(size int) (fd int, err error) {
+	if size <= 0 {
+		return -1, EINVAL
+	}
+	return EpollCreate1(0)
+}
+
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) = SYS_EPOLL_PWAIT
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
@@ -57,6 +66,11 @@ func Lstat(path string, stat *Stat_t) (err error) {
 //sys	Statfs(path string, buf *Statfs_t) (err error)
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error)
+
+func Ustat(dev int, ubuf *Ustat_t) (err error) {
+	return ENOSYS
+}
+
 //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
 //sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
 //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
@@ -85,6 +99,18 @@ func setTimeval(sec, usec int64) Timeval {
 	return Timeval{Sec: sec, Usec: usec}
 }
 
+func futimesat(dirfd int, path string, tv *[2]Timeval) (err error) {
+	if tv == nil {
+		return utimensat(dirfd, path, nil, 0)
+	}
+
+	ts := []Timespec{
+		NsecToTimespec(TimevalToNsec(tv[0])),
+		NsecToTimespec(TimevalToNsec(tv[1])),
+	}
+	return utimensat(dirfd, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
+}
+
 func Time(t *Time_t) (Time_t, error) {
 	var tv Timeval
 	err := Gettimeofday(&tv)
@@ -105,6 +131,18 @@ func Utime(path string, buf *Utimbuf) error {
 	return Utimes(path, tv)
 }
 
+func utimes(path string, tv *[2]Timeval) (err error) {
+	if tv == nil {
+		return utimensat(AT_FDCWD, path, nil, 0)
+	}
+
+	ts := []Timespec{
+		NsecToTimespec(TimevalToNsec(tv[0])),
+		NsecToTimespec(TimevalToNsec(tv[1])),
+	}
+	return utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
+}
+
 func Pipe(p []int) (err error) {
 	if len(p) != 2 {
 		return EINVAL
@@ -161,22 +199,6 @@ func Pause() (err error) {
 	return
 }
 
-// TODO(dfc): constants that should be in zsysnum_linux_arm64.go, remove
-// these when the deprecated syscalls that the syscall package relies on
-// are removed.
-const (
-	SYS_GETPGRP      = 1060
-	SYS_UTIMES       = 1037
-	SYS_FUTIMESAT    = 1066
-	SYS_PAUSE        = 1061
-	SYS_USTAT        = 1070
-	SYS_UTIME        = 1063
-	SYS_LCHOWN       = 1032
-	SYS_TIME         = 1062
-	SYS_EPOLL_CREATE = 1042
-	SYS_EPOLL_WAIT   = 1069
-)
-
 func Poll(fds []PollFd, timeout int) (n int, err error) {
 	var ts *Timespec
 	if timeout >= 0 {

unix/syscall_linux_mips64x.go

@@ -8,6 +8,7 @@
 package unix
 
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
@@ -47,6 +48,7 @@ func Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err
 //sys	Statfs(path string, buf *Statfs_t) (err error)
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error)
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
 //sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
 //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
@@ -65,6 +67,7 @@ func Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err
 //sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
 //sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 
 func Time(t *Time_t) (tt Time_t, err error) {
@@ -80,6 +83,7 @@ func Time(t *Time_t) (tt Time_t, err error) {
 }
 
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 func setTimespec(sec, nsec int64) Timespec {
 	return Timespec{Sec: sec, Nsec: nsec}

unix/syscall_linux_mipsx.go

@@ -15,6 +15,8 @@ import (
 func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err syscall.Errno)
 
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
+//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Ftruncate(fd int, length int64) (err error) = SYS_FTRUNCATE64
@@ -33,13 +35,12 @@ func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr,
 //sysnb	Setregid(rgid int, egid int) (err error)
 //sysnb	Setresgid(rgid int, egid int, sgid int) (err error)
 //sysnb	Setresuid(ruid int, euid int, suid int) (err error)
-
 //sysnb	Setreuid(ruid int, euid int) (err error)
 //sys	Shutdown(fd int, how int) (err error)
 //sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error)
-
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error) = SYS_TRUNCATE64
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
 //sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
 //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
@@ -61,16 +62,17 @@ func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr,
 //sys	Ioperm(from int, num int, on int) (err error)
 //sys	Iopl(level int) (err error)
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 //sysnb	Time(t *Time_t) (tt Time_t, err error)
+//sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 //sys	Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64
 //sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
 //sys	Fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
 //sys	Stat(path string, stat *Stat_t) (err error) = SYS_STAT64
 
-//sys	Utime(path string, buf *Utimbuf) (err error)
-//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Pause() (err error)
 
 func Fstatfs(fd int, buf *Statfs_t) (err error) {

unix/syscall_linux_ppc64x.go

@@ -7,8 +7,9 @@
 
 package unix
 
-//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
+//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
 //sys	Fstat(fd int, stat *Stat_t) (err error)
@@ -45,6 +46,7 @@ package unix
 //sys	Statfs(path string, buf *Statfs_t) (err error)
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error) = SYS_SYNC_FILE_RANGE2
 //sys	Truncate(path string, length int64) (err error)
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
 //sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
 //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
@@ -63,10 +65,11 @@ package unix
 //sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
 //sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 //sysnb	Time(t *Time_t) (tt Time_t, err error)
-
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 func setTimespec(sec, nsec int64) Timespec {
 	return Timespec{Sec: sec, Nsec: nsec}

unix/syscall_linux_s390x.go

@@ -11,6 +11,7 @@ import (
 )
 
 //sys	Dup2(oldfd int, newfd int) (err error)
+//sysnb	EpollCreate(size int) (fd int, err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
 //sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
 //sys	Fchown(fd int, uid int, gid int) (err error)
@@ -44,9 +45,11 @@ import (
 //sys	Statfs(path string, buf *Statfs_t) (err error)
 //sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
 //sys	Truncate(path string, length int64) (err error)
+//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
 //sysnb	getgroups(n int, list *_Gid_t) (nn int, err error)
 //sysnb	setgroups(n int, list *_Gid_t) (err error)
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 
 func Time(t *Time_t) (tt Time_t, err error) {
@@ -62,6 +65,7 @@ func Time(t *Time_t) (tt Time_t, err error) {
 }
 
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 func setTimespec(sec, nsec int64) Timespec {
 	return Timespec{Sec: sec, Nsec: nsec}

unix/syscall_linux_sparc64.go

@@ -68,6 +68,7 @@ func Iopl(level int) (err error) {
 	return ENOSYS
 }
 
+//sys	futimesat(dirfd int, path string, times *[2]Timeval) (err error)
 //sysnb	Gettimeofday(tv *Timeval) (err error)
 
 func Time(t *Time_t) (tt Time_t, err error) {
@@ -83,6 +84,7 @@ func Time(t *Time_t) (tt Time_t, err error) {
 }
 
 //sys	Utime(path string, buf *Utimbuf) (err error)
+//sys	utimes(path string, times *[2]Timeval) (err error)
 
 func setTimespec(sec, nsec int64) Timespec {
 	return Timespec{Sec: sec, Nsec: nsec}