syscall: split implementation of Pipe/Pipe2 per GOOS

Updates #9974

This proposal moves the definition of Pipe an Pipe2 from the generic
syscall_linux.go to the GOOS specific variants. This is in preparation
for the arm64 port.

For platforms where pipe2(2) is not supported in the minimum 2.6.23 kernel,
amd64 and 386, we retain pipe(2). For all other platforms pipe(2) is removed
and Pipe forwards to pipe2(2).

Because mksycall.pl does not sort symbols before generating the output file
the diff includes some unavoidable code moves as Pipe and Pipe2 are processed
latter in the run.

Discussion: https://groups.google.com/forum/#!topic/golang-dev/zpeFtN2z5Fc

Change-Id: Ie26d6761eeb9760dbaff974ee8bc0d57a9ceaee4
Reviewed-on: https://go-review.googlesource.com/5833Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

src/syscall/syscall_linux.go

@@ -29,32 +29,6 @@ func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 	return openat(dirfd, path, flags|O_LARGEFILE, mode)
 }
 
-//sysnb	pipe(p *[2]_C_int) (err error)
-
-func Pipe(p []int) (err error) {
-	if len(p) != 2 {
-		return EINVAL
-	}
-	var pp [2]_C_int
-	err = pipe(&pp)
-	p[0] = int(pp[0])
-	p[1] = int(pp[1])
-	return
-}
-
-//sysnb pipe2(p *[2]_C_int, flags int) (err error)
-
-func Pipe2(p []int, flags int) (err error) {
-	if len(p) != 2 {
-		return EINVAL
-	}
-	var pp [2]_C_int
-	err = pipe2(&pp, flags)
-	p[0] = int(pp[0])
-	p[1] = int(pp[1])
-	return
-}
-
 //sys	utimes(path string, times *[2]Timeval) (err error)
 
 func Utimes(path string, tv []Timeval) (err error) {

src/syscall/syscall_linux_386.go

@@ -28,6 +28,32 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 	return
 }
 
+//sysnb	pipe(p *[2]_C_int) (err error)
+
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe(&pp)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, flags)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
 // 64-bit file system and 32-bit uid calls
 // (386 default is 32-bit file system and 16-bit uid).
 //sys	Chown(path string, uid int, gid int) (err error) = SYS_CHOWN32

src/syscall/syscall_linux_amd64.go

@@ -97,6 +97,32 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 	return
 }
 
+//sysnb	pipe(p *[2]_C_int) (err error)
+
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe(&pp)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, flags)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
 func (r *PtraceRegs) PC() uint64 { return r.Rip }
 
 func (r *PtraceRegs) SetPC(pc uint64) { r.Rip = pc }

src/syscall/syscall_linux_arm.go

@@ -23,6 +23,30 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 	return
 }
 
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, 0)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, flags)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
 // Underlying system call writes to newoffset via pointer.
 // Implemented in assembly to avoid allocation.
 func seek(fd int, offset int64, whence int) (newoffset int64, err Errno)

src/syscall/syscall_linux_ppc64x.go

@@ -80,6 +80,30 @@ func NsecToTimeval(nsec int64) (tv Timeval) {
 	return
 }
 
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, 0)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+//sysnb pipe2(p *[2]_C_int, flags int) (err error)
+
+func Pipe2(p []int, flags int) (err error) {
+	if len(p) != 2 {
+		return EINVAL
+	}
+	var pp [2]_C_int
+	err = pipe2(&pp, flags)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
 func (r *PtraceRegs) PC() uint64 { return r.Nip }
 
 func (r *PtraceRegs) SetPC(pc uint64) { r.Nip = pc }

src/syscall/zsyscall_linux_386.go

@@ -41,26 +41,6 @@ func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe(p *[2]_C_int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func utimes(path string, times *[2]Timeval) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
@@ -1396,6 +1376,26 @@ func Munlockall() (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe(p *[2]_C_int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Chown(path string, uid int, gid int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_amd64.go

@@ -41,26 +41,6 @@ func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe(p *[2]_C_int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func utimes(path string, times *[2]Timeval) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
@@ -1959,3 +1939,23 @@ func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int6
 	}
 	return
 }
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]_C_int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}

src/syscall/zsyscall_linux_arm.go

@@ -41,26 +41,6 @@ func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe(p *[2]_C_int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func utimes(path string, times *[2]Timeval) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
@@ -1396,6 +1376,16 @@ func Munlockall() (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error) {
 	r0, _, e1 := Syscall(SYS_ACCEPT, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	fd = int(r0)

src/syscall/zsyscall_linux_ppc64.go

@@ -41,26 +41,6 @@ func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe(p *[2]_C_int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func utimes(path string, times *[2]Timeval) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
@@ -1980,3 +1960,13 @@ func Time(t *Time_t) (tt Time_t, err error) {
 	}
 	return
 }
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}

src/syscall/zsyscall_linux_ppc64le.go

@@ -41,26 +41,6 @@ func openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func pipe(p *[2]_C_int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func pipe2(p *[2]_C_int, flags int) (err error) {
-	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func utimes(path string, times *[2]Timeval) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)
@@ -1980,3 +1960,13 @@ func Time(t *Time_t) (tt Time_t, err error) {
 	}
 	return
 }
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe2(p *[2]_C_int, flags int) (err error) {
+	_, _, e1 := RawSyscall(SYS_PIPE2, uintptr(unsafe.Pointer(p)), uintptr(flags), 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}