dirent.c

   1 #include <dirent.h>
   2 #include <fcntl.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <sys/stat.h>
   6
   7 struct __dirent_dir {
   8         int fd;
   9         int buf_pos;
  10         int buf_end;
  11         char buf[2048];
  12 };
  13
  14 DIR *opendir(char *path)
  15 {
  16         DIR *dir;
  17         int fd;
  18         if ((fd = open(path, O_RDONLY | O_DIRECTORY)) < 0)
  19                 return NULL;
  20         fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
  21         if (!(dir = malloc(sizeof(*dir)))) {
  22                 close(fd);
  23                 return NULL;
  24         }
  25         memset(dir, 0, sizeof(*dir));
  26         dir->fd = fd;
  27         return dir;
  28 }
  29
  30 int closedir(DIR *dir)
  31 {
  32         int ret;
  33         ret = close(dir->fd);
  34         free(dir);
  35         return ret;
  36 }
  37
  38 int getdents(int fd, struct dirent *de, size_t len);
  39
  40 struct dirent *readdir(DIR *dir)
  41 {
  42         struct dirent *de;
  43         int len;
  44         if (dir->buf_pos >= dir->buf_end) {
  45                 len = getdents(dir->fd, (void *) dir->buf, sizeof(dir->buf));
  46                 if (len <= 0)
  47                         return NULL;
  48                 dir->buf_pos = 0;
  49                 dir->buf_end = len;
  50         }
  51         de = (void *) (dir->buf + dir->buf_pos);
  52         dir->buf_pos += de->d_reclen;
  53         return de;
  54 }