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Diffstat (limited to 'libc/sysdeps/linux/common/getdents.c')
-rw-r--r--libc/sysdeps/linux/common/getdents.c119
1 files changed, 0 insertions, 119 deletions
diff --git a/libc/sysdeps/linux/common/getdents.c b/libc/sysdeps/linux/common/getdents.c
deleted file mode 100644
index 7bb129a51..000000000
--- a/libc/sysdeps/linux/common/getdents.c
+++ /dev/null
@@ -1,119 +0,0 @@
-/* Copyright (C) 1993, 95, 96, 97, 98, 99 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Library General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
-
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Library General Public License for more details.
-
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
-
-#include <stdlib.h>
-#include <errno.h>
-#include <dirent.h>
-#include <stddef.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/param.h>
-#include <sys/types.h>
-
-#include <sysdep.h>
-
-typedef long __kernel_off_t;
-
-#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
-
-
-extern int _getdents __P ((int fd, char *buf, size_t nbytes));
-
-/* For Linux we need a special version of this file since the
- definition of `struct dirent' is not the same for the kernel and
- the libc. There is one additional field which might be introduced
- in the kernel structure in the future. Here is a copy of the kernel
- struct dirent...
- */
-struct kernel_dirent {
- long d_ino;
- __kernel_off_t d_off;
- unsigned short d_reclen;
- char d_name[256]; /* We must not include limits.h! */
-};
-
-
-
-#ifdef GETDENTS64
-# define __getdents __getdents64
-# define dirent dirent64
-#endif
-
-/* The problem here is that we cannot simply read the next NBYTES
- bytes. We need to take the additional field into account. We use
- some heuristic. Assuming the directory contains names with 14
- characters on average we can compute an estimated number of entries
- which fit in the buffer. Taking this number allows us to specify a
- reasonable number of bytes to read. If we should be wrong, we can
- reset the file descriptor. In practice the kernel is limiting the
- amount of data returned much more then the reduced buffer size. */
-ssize_t getdents (int fd, char *buf, size_t nbytes)
-{
- off_t last_offset = 0;
- size_t red_nbytes;
- struct kernel_dirent *skdp, *kdp;
- struct dirent *dp;
- int retval;
- const size_t size_diff = (offsetof (struct dirent, d_name)
- - offsetof (struct kernel_dirent, d_name));
-
- red_nbytes = nbytes - ((nbytes / (offsetof (struct dirent, d_name) + 14))
- * size_diff);
-
- dp = (struct dirent *) buf;
- skdp = kdp = malloc (red_nbytes);
-
- retval = _getdents(fd, (char *) kdp, red_nbytes);
-
- if (retval == -1)
- return -1;
-
- while ((char *) kdp < (char *) skdp + retval)
- {
- const size_t alignment = __alignof__ (struct dirent);
- /* Since kdp->d_reclen is already aligned for the kernel structure
- this may compute a value that is bigger than necessary. */
- size_t new_reclen = ((kdp->d_reclen + size_diff + alignment - 1)
- & ~(alignment - 1));
- if ((char *) dp + new_reclen > buf + nbytes)
- {
- /* Our heuristic failed. We read too many entries. Reset
- the stream. `last_offset' contains the last known
- position. If it is zero this is the first record we are
- reading. In this case do a relative search. */
- if (last_offset == 0)
- lseek (fd, -retval, SEEK_CUR);
- else
- lseek (fd, last_offset, SEEK_SET);
- break;
- }
-
- last_offset = kdp->d_off;
- dp->d_ino = kdp->d_ino;
- dp->d_off = kdp->d_off;
- dp->d_reclen = new_reclen;
- dp->d_type = DT_UNKNOWN;
- memcpy (dp->d_name, kdp->d_name,
- kdp->d_reclen - offsetof (struct kernel_dirent, d_name));
-
- dp = (struct dirent *) ((char *) dp + new_reclen);
- kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen);
- }
-
- return (char *) dp - buf;
-}