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-rw-r--r--sysdeps/posix/readdir_r.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/sysdeps/posix/readdir_r.c b/sysdeps/posix/readdir_r.c
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+++ b/sysdeps/posix/readdir_r.c
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+/* Copyright (C) 1991,92,93,94,95,96,97,98,99,2000,02,10
+ 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 Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <limits.h>
+#include <stddef.h>
+#include <string.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <assert.h>
+
+#include <dirstream.h>
+
+#ifndef __READDIR_R
+# define __READDIR_R __readdir_r
+# define __GETDENTS __getdents
+# define DIRENT_TYPE struct dirent
+# define __READDIR_R_ALIAS
+#endif
+
+/* Read a directory entry from DIRP. */
+int
+__READDIR_R (DIR *dirp, DIRENT_TYPE *entry, DIRENT_TYPE **result)
+{
+ DIRENT_TYPE *dp;
+ size_t reclen;
+ const int saved_errno = errno;
+
+ __libc_lock_lock (dirp->lock);
+
+ do
+ {
+ if (dirp->offset >= dirp->size)
+ {
+ /* We've emptied out our buffer. Refill it. */
+
+ size_t maxread;
+ ssize_t bytes;
+
+#ifndef _DIRENT_HAVE_D_RECLEN
+ /* Fixed-size struct; must read one at a time (see below). */
+ maxread = sizeof *dp;
+#else
+ maxread = dirp->allocation;
+#endif
+
+ bytes = __GETDENTS (dirp->fd, dirp->data, maxread);
+ if (bytes <= 0)
+ {
+ /* On some systems getdents fails with ENOENT when the
+ open directory has been rmdir'd already. POSIX.1
+ requires that we treat this condition like normal EOF. */
+ if (bytes < 0 && errno == ENOENT)
+ {
+ bytes = 0;
+ __set_errno (saved_errno);
+ }
+
+ dp = NULL;
+ /* Reclen != 0 signals that an error occurred. */
+ reclen = bytes != 0;
+ break;
+ }
+ dirp->size = (size_t) bytes;
+
+ /* Reset the offset into the buffer. */
+ dirp->offset = 0;
+ }
+
+ dp = (DIRENT_TYPE *) &dirp->data[dirp->offset];
+
+#ifdef _DIRENT_HAVE_D_RECLEN
+ reclen = dp->d_reclen;
+#else
+ /* The only version of `struct dirent*' that lacks `d_reclen'
+ is fixed-size. */
+ assert (sizeof dp->d_name > 1);
+ reclen = sizeof *dp;
+ /* The name is not terminated if it is the largest possible size.
+ Clobber the following byte to ensure proper null termination. We
+ read just one entry at a time above so we know that byte will not
+ be used later. */
+ dp->d_name[sizeof dp->d_name] = '\0';
+#endif
+
+ dirp->offset += reclen;
+
+#ifdef _DIRENT_HAVE_D_OFF
+ dirp->filepos = dp->d_off;
+#else
+ dirp->filepos += reclen;
+#endif
+
+ /* Skip deleted files. */
+ }
+ while (dp->d_ino == 0);
+
+ if (dp != NULL)
+ {
+#ifdef GETDENTS_64BIT_ALIGNED
+ /* The d_reclen value might include padding which is not part of
+ the DIRENT_TYPE data structure. */
+ reclen = MIN (reclen,
+ offsetof (DIRENT_TYPE, d_name) + sizeof (dp->d_name));
+#endif
+ *result = memcpy (entry, dp, reclen);
+#ifdef GETDENTS_64BIT_ALIGNED
+ entry->d_reclen = reclen;
+#endif
+ }
+ else
+ *result = NULL;
+
+ __libc_lock_unlock (dirp->lock);
+
+ return dp != NULL ? 0 : reclen ? errno : 0;
+}
+
+#ifdef __READDIR_R_ALIAS
+weak_alias (__readdir_r, readdir_r)
+#endif