tools/internal/fastwalk/fastwalk_darwin.go

120 строки
2.7 KiB
Go

// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build darwin && cgo
// +build darwin,cgo
package fastwalk
/*
#include <dirent.h>
// fastwalk_readdir_r wraps readdir_r so that we don't have to pass a dirent**
// result pointer which triggers CGO's "Go pointer to Go pointer" check unless
// we allocat the result dirent* with malloc.
//
// fastwalk_readdir_r returns 0 on success, -1 upon reaching the end of the
// directory, or a positive error number to indicate failure.
static int fastwalk_readdir_r(DIR *fd, struct dirent *entry) {
struct dirent *result;
int ret = readdir_r(fd, entry, &result);
if (ret == 0 && result == NULL) {
ret = -1; // EOF
}
return ret;
}
*/
import "C"
import (
"os"
"syscall"
"unsafe"
)
func readDir(dirName string, fn func(dirName, entName string, typ os.FileMode) error) error {
fd, err := openDir(dirName)
if err != nil {
return &os.PathError{Op: "opendir", Path: dirName, Err: err}
}
defer C.closedir(fd)
skipFiles := false
var dirent syscall.Dirent
for {
ret := int(C.fastwalk_readdir_r(fd, (*C.struct_dirent)(unsafe.Pointer(&dirent))))
if ret != 0 {
if ret == -1 {
break // EOF
}
if ret == int(syscall.EINTR) {
continue
}
return &os.PathError{Op: "readdir", Path: dirName, Err: syscall.Errno(ret)}
}
if dirent.Ino == 0 {
continue
}
typ := dtToType(dirent.Type)
if skipFiles && typ.IsRegular() {
continue
}
name := (*[len(syscall.Dirent{}.Name)]byte)(unsafe.Pointer(&dirent.Name))[:]
name = name[:dirent.Namlen]
for i, c := range name {
if c == 0 {
name = name[:i]
break
}
}
// Check for useless names before allocating a string.
if string(name) == "." || string(name) == ".." {
continue
}
if err := fn(dirName, string(name), typ); err != nil {
if err != ErrSkipFiles {
return err
}
skipFiles = true
}
}
return nil
}
func dtToType(typ uint8) os.FileMode {
switch typ {
case syscall.DT_BLK:
return os.ModeDevice
case syscall.DT_CHR:
return os.ModeDevice | os.ModeCharDevice
case syscall.DT_DIR:
return os.ModeDir
case syscall.DT_FIFO:
return os.ModeNamedPipe
case syscall.DT_LNK:
return os.ModeSymlink
case syscall.DT_REG:
return 0
case syscall.DT_SOCK:
return os.ModeSocket
}
return ^os.FileMode(0)
}
// openDir wraps opendir(3) and handles any EINTR errors. The returned *DIR
// needs to be closed with closedir(3).
func openDir(path string) (*C.DIR, error) {
name, err := syscall.BytePtrFromString(path)
if err != nil {
return nil, err
}
for {
fd, err := C.opendir((*C.char)(unsafe.Pointer(name)))
if err != syscall.EINTR {
return fd, err
}
}
}