klibc/klibc/readdir.c


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/*
 * readdir.c: opendir/readdir/closedir
 */

#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>

#define __KLIBC_DIRENT_INTERNALS
#include <dirent.h>

DIR *opendir(const char *name)
{
  DIR *dp = malloc(sizeof(DIR));

  if ( !dp )
    return NULL;

  dp->__fd = open(name, O_DIRECTORY|O_RDONLY);

  if ( dp->__fd < 0 ) {
    free(dp);
    return NULL;
  }

  dp->bytes_left = 0;

  return dp;
}

struct dirent *readdir(DIR *dir)
{
  struct dirent *dent;
  int rv;
  
  if ( !dir->bytes_left ) {
    rv = getdents(dir->__fd, dir->buffer, sizeof(dir->buffer));
    if ( rv <= 0 )
      return NULL;
    dir->bytes_left = rv;
    dir->next = dir->buffer;
  }

  dent = dir->next;
  dir->next = (struct dirent *)((char *)dir->next + dent->d_reclen);
  dir->bytes_left -= dent->d_reclen;
  
  return dent;
}

int closedir(DIR *dir)
{
  int rv;
  rv = close(dir->__fd);
  free(dir);
  return rv;
}