go.sys/unix: use syscall.Errno for errors

If we use a local type, it won't compare properly with errors from
the rest of the standard library. Errors are the one type from syscall
that propagates through the system, so it's important to have only
one type for them.

Ditto for syscall.Signal.

LGTM=dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/123490043

unix/bpf_bsd.go

@@ -9,6 +9,7 @@
 package unix
 
 import (
+	"syscall"
 	"unsafe"
 )
 
@@ -24,7 +25,7 @@ func BpfBuflen(fd int) (int, error) {
 	var l int
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGBLEN, uintptr(unsafe.Pointer(&l)))
 	if err != 0 {
-		return 0, Errno(err)
+		return 0, syscall.Errno(err)
 	}
 	return l, nil
 }
@@ -32,7 +33,7 @@ func BpfBuflen(fd int) (int, error) {
 func SetBpfBuflen(fd, l int) (int, error) {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSBLEN, uintptr(unsafe.Pointer(&l)))
 	if err != 0 {
-		return 0, Errno(err)
+		return 0, syscall.Errno(err)
 	}
 	return l, nil
 }
@@ -41,7 +42,7 @@ func BpfDatalink(fd int) (int, error) {
 	var t int
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGDLT, uintptr(unsafe.Pointer(&t)))
 	if err != 0 {
-		return 0, Errno(err)
+		return 0, syscall.Errno(err)
 	}
 	return t, nil
 }
@@ -49,7 +50,7 @@ func BpfDatalink(fd int) (int, error) {
 func SetBpfDatalink(fd, t int) (int, error) {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSDLT, uintptr(unsafe.Pointer(&t)))
 	if err != 0 {
-		return 0, Errno(err)
+		return 0, syscall.Errno(err)
 	}
 	return t, nil
 }
@@ -57,7 +58,7 @@ func SetBpfDatalink(fd, t int) (int, error) {
 func SetBpfPromisc(fd, m int) error {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCPROMISC, uintptr(unsafe.Pointer(&m)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -65,7 +66,7 @@ func SetBpfPromisc(fd, m int) error {
 func FlushBpf(fd int) error {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCFLUSH, 0)
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -79,7 +80,7 @@ func BpfInterface(fd int, name string) (string, error) {
 	var iv ivalue
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGETIF, uintptr(unsafe.Pointer(&iv)))
 	if err != 0 {
-		return "", Errno(err)
+		return "", syscall.Errno(err)
 	}
 	return name, nil
 }
@@ -89,7 +90,7 @@ func SetBpfInterface(fd int, name string) error {
 	copy(iv.name[:], []byte(name))
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSETIF, uintptr(unsafe.Pointer(&iv)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -98,7 +99,7 @@ func BpfTimeout(fd int) (*Timeval, error) {
 	var tv Timeval
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGRTIMEOUT, uintptr(unsafe.Pointer(&tv)))
 	if err != 0 {
-		return nil, Errno(err)
+		return nil, syscall.Errno(err)
 	}
 	return &tv, nil
 }
@@ -106,7 +107,7 @@ func BpfTimeout(fd int) (*Timeval, error) {
 func SetBpfTimeout(fd int, tv *Timeval) error {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSRTIMEOUT, uintptr(unsafe.Pointer(tv)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -115,7 +116,7 @@ func BpfStats(fd int) (*BpfStat, error) {
 	var s BpfStat
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGSTATS, uintptr(unsafe.Pointer(&s)))
 	if err != 0 {
-		return nil, Errno(err)
+		return nil, syscall.Errno(err)
 	}
 	return &s, nil
 }
@@ -123,7 +124,7 @@ func BpfStats(fd int) (*BpfStat, error) {
 func SetBpfImmediate(fd, m int) error {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCIMMEDIATE, uintptr(unsafe.Pointer(&m)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -134,7 +135,7 @@ func SetBpf(fd int, i []BpfInsn) error {
 	p.Insns = (*BpfInsn)(unsafe.Pointer(&i[0]))
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSETF, uintptr(unsafe.Pointer(&p)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }
@@ -143,7 +144,7 @@ func CheckBpfVersion(fd int) error {
 	var v BpfVersion
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCVERSION, uintptr(unsafe.Pointer(&v)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	if v.Major != BPF_MAJOR_VERSION || v.Minor != BPF_MINOR_VERSION {
 		return EINVAL
@@ -155,7 +156,7 @@ func BpfHeadercmpl(fd int) (int, error) {
 	var f int
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCGHDRCMPLT, uintptr(unsafe.Pointer(&f)))
 	if err != 0 {
-		return 0, Errno(err)
+		return 0, syscall.Errno(err)
 	}
 	return f, nil
 }
@@ -163,7 +164,7 @@ func BpfHeadercmpl(fd int) (int, error) {
 func SetBpfHeadercmpl(fd, f int) error {
 	_, _, err := Syscall(SYS_IOCTL, uintptr(fd), BIOCSHDRCMPLT, uintptr(unsafe.Pointer(&f)))
 	if err != 0 {
-		return Errno(err)
+		return syscall.Errno(err)
 	}
 	return nil
 }