simple accessors for Dir mode bits

R=rsc
DELTA=71  (71 added, 0 deleted, 0 changed)
OCL=24687
CL=24694

src/lib/os/os_types.go

@@ -4,6 +4,8 @@
 
 package os
 
+import "syscall"
+
 // An operating-system independent representation of Unix data structures.
 // OS-specific routines in this directory convert the OS-local versions to these.
 
@@ -24,3 +26,35 @@ type Dir struct {
 	Ctime_ns	uint64;	// nanoseconds since 1970
 	Name	string;
 }
+
+func (dir *Dir) IsFifo() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFIFO
+}
+
+func (dir *Dir) IsChar() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFCHR
+}
+
+func (dir *Dir) IsDirectory() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFDIR
+}
+
+func (dir *Dir) IsBlock() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFBLK
+}
+
+func (dir *Dir) IsRegular() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFREG
+}
+
+func (dir *Dir) IsSymlink() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFLNK
+}
+
+func (dir *Dir) IsSocket() bool {
+	return (dir.Mode & syscall.S_IFMT) == syscall.S_IFSOCK
+}
+
+func (dir *Dir) Permission() int {
+	return int(dir.Mode & 0777)
+}

src/lib/syscall/types_amd64_darwin.go

@@ -69,6 +69,25 @@ const (
 	NAME_MAX = 255;
 )
 
+// Dir.Mode bits
+const (
+	S_IFMT = 0170000;	      /* type of file */
+		S_IFIFO  = 0010000;  /* named pipe (fifo) */
+		S_IFCHR  = 0020000;  /* character special */
+		S_IFDIR  = 0040000;  /* directory */
+		S_IFBLK  = 0060000;  /* block special */
+		S_IFREG  = 0100000;  /* regular */
+		S_IFLNK  = 0120000;  /* symbolic link */
+		S_IFSOCK = 0140000;  /* socket */
+		S_IFWHT  = 0160000;  /* whiteout */
+	S_ISUID = 0004000;  /* set user id on execution */
+	S_ISGID = 0002000;  /* set group id on execution */
+	S_ISVTX = 0001000;  /* save swapped text even after use */
+	S_IRUSR = 0000400;  /* read permission, owner */
+	S_IWUSR = 0000200;  /* write permission, owner */
+	S_IXUSR = 0000100;  /* execute/search permission, owner */
+)
+
 type Stat_t struct {
 	Dev	uint32;
 	Mode	uint16;

src/lib/syscall/types_amd64_linux.go

@@ -69,6 +69,24 @@ const (
 	NAME_MAX = 255;
 )
 
+// Dir.Mode bits
+const (
+	S_IFMT = 0170000;	      /* type of file */
+		S_IFIFO  = 0010000;  /* named pipe (fifo) */
+		S_IFCHR  = 0020000;  /* character special */
+		S_IFDIR  = 0040000;  /* directory */
+		S_IFBLK  = 0060000;  /* block special */
+		S_IFREG  = 0100000;  /* regular */
+		S_IFLNK  = 0120000;  /* symbolic link */
+		S_IFSOCK = 0140000;  /* socket */
+	S_ISUID = 0004000;  /* set user id on execution */
+	S_ISGID = 0002000;  /* set group id on execution */
+	S_ISVTX = 0001000;  /* save swapped text even after use */
+	S_IRUSR = 0000400;  /* read permission, owner */
+	S_IWUSR = 0000200;  /* write permission, owner */
+	S_IXUSR = 0000100;  /* execute/search permission, owner */
+)
+
 type Stat_t struct {
 	Dev	uint64;
 	Ino	uint64;