dirent.c

   1 #include <dirent.h>
   2 #include <fcntl.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <sys/stat.h>
   6 #include <unistd.h>
   7
   8 struct __dirent_dir {
   9         int fd;
  10         int buf_pos;
  11         int buf_end;
  12         char buf[2048];
  13 };
  14
  15 DIR *opendir(char *path)
  16 {
  17         DIR *dir;
  18         int fd;
  19         if ((fd = open(path, O_RDONLY | O_DIRECTORY)) < 0)
  20                 return NULL;
  21         fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
  22         if (!(dir = malloc(sizeof(*dir)))) {
  23                 close(fd);
  24                 return NULL;
  25         }
  26         memset(dir, 0, sizeof(*dir));
  27         dir->fd = fd;
  28         return dir;
  29 }
  30
  31 int closedir(DIR *dir)
  32 {
  33         int ret;
  34         ret = close(dir->fd);
  35         free(dir);
  36         return ret;
  37 }
  38
  39 int getdents(int fd, struct dirent *de, size_t len);
  40
  41 struct dirent *readdir(DIR *dir)
  42 {
  43         struct dirent *de;
  44         int len;
  45         if (dir->buf_pos >= dir->buf_end) {
  46                 len = getdents(dir->fd, (void *) dir->buf, sizeof(dir->buf));
  47                 if (len <= 0)
  48                         return NULL;
  49                 dir->buf_pos = 0;
  50                 dir->buf_end = len;
  51         }
  52         de = (void *) (dir->buf + dir->buf_pos);
  53         dir->buf_pos += de->d_reclen;
  54         return de;
  55 }