summaryrefslogtreecommitdiff
path: root/dirent/scandir-tail-common.c
diff options
context:
space:
mode:
Diffstat (limited to 'dirent/scandir-tail-common.c')
-rw-r--r--dirent/scandir-tail-common.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/dirent/scandir-tail-common.c b/dirent/scandir-tail-common.c
new file mode 100644
index 0000000000..f89cf77b56
--- /dev/null
+++ b/dirent/scandir-tail-common.c
@@ -0,0 +1,103 @@
+/* Common implementation for scandir{at}.
+ Copyright (C) 2018 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 <string.h>
+#include <errno.h>
+
+int
+SCANDIR_TAIL (DIR *dp,
+ DIRENT_TYPE ***namelist,
+ int (*select) (const DIRENT_TYPE *),
+ int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **))
+{
+ if (dp == NULL)
+ return -1;
+
+ int save = errno;
+ __set_errno (0);
+
+ int result;
+ struct scandir_cancel_struct c = { .dp = dp };
+ __libc_cleanup_push (&__scandir_cancel_handler, &c);
+
+ DIRENT_TYPE **v = NULL;
+ size_t vsize = 0;
+ DIRENT_TYPE *d;
+ while ((d = READDIR (dp)) != NULL)
+ {
+ if (select != NULL)
+ {
+ int selected = (*select) (d);
+
+ /* The SELECT function might have set errno to non-zero on
+ success. It was zero before and it needs to be again to
+ make the later tests work. */
+ __set_errno (0);
+
+ if (!selected)
+ continue;
+ }
+
+ if (__glibc_unlikely (c.cnt == vsize))
+ {
+ if (vsize == 0)
+ vsize = 10;
+ else
+ vsize *= 2;
+ DIRENT_TYPE **new = realloc (v, vsize * sizeof *v);
+ if (new == NULL)
+ break;
+ c.v = v = new;
+ }
+
+ size_t dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
+ DIRENT_TYPE *vnew = malloc (dsize);
+ if (vnew == NULL)
+ break;
+ v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
+
+ /* Ignore errors from readdir, malloc or realloc. These functions
+ might have set errno to non-zero on success. It was zero before
+ and it needs to be again to make the latter tests work. */
+ __set_errno (0);
+ }
+
+ if (__glibc_likely (errno == 0))
+ {
+ __closedir (dp);
+
+ /* Sort the list if we have a comparison function to sort with. */
+ if (cmp != NULL)
+ qsort (v, c.cnt, sizeof *v, (__compar_fn_t) cmp);
+
+ *namelist = v;
+ result = c.cnt;
+ }
+ else
+ {
+ /* This frees everything and calls closedir. */
+ __scandir_cancel_handler (&c);
+ result = -1;
+ }
+
+ __libc_cleanup_pop (0);
+
+ if (result >= 0)
+ __set_errno (save);
+ return result;
+}