summaryrefslogtreecommitdiff
path: root/openbsd-compat/recallocarray.c
diff options
context:
space:
mode:
authorDamien Miller <djm@mindrot.org>2017-06-01 15:25:13 +1000
committerDamien Miller <djm@mindrot.org>2017-06-01 15:25:13 +1000
commit151c6e433a5f5af761c78de87d7b5d30a453cf5e (patch)
tree77cdffcee99995b20821a8f2a957504e861475d5 /openbsd-compat/recallocarray.c
parent01e6f78924da308447e71e9a32c8a6104ef4e888 (diff)
add recallocarray replacement and dependency
recallocarray() needs getpagesize() so add a tiny replacement for that.
Diffstat (limited to 'openbsd-compat/recallocarray.c')
-rw-r--r--openbsd-compat/recallocarray.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/openbsd-compat/recallocarray.c b/openbsd-compat/recallocarray.c
new file mode 100644
index 00000000..50674170
--- /dev/null
+++ b/openbsd-compat/recallocarray.c
@@ -0,0 +1,88 @@
+/* $OpenBSD: recallocarray.c,v 1.1 2017/03/06 18:44:21 otto Exp $ */
+/*
+ * Copyright (c) 2008, 2017 Otto Moerbeek <otto@drijf.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* OPENBSD ORIGINAL: lib/libc/stdlib/recallocarray.c */
+
+#include "includes.h"
+#ifndef HAVE_RECALLOCARRAY
+
+#include <errno.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+/*
+ * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
+ * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
+ */
+#define MUL_NO_OVERFLOW ((size_t)1 << (sizeof(size_t) * 4))
+
+void *
+recallocarray(void *ptr, size_t oldnmemb, size_t newnmemb, size_t size)
+{
+ size_t oldsize, newsize;
+ void *newptr;
+
+ if (ptr == NULL)
+ return calloc(newnmemb, size);
+
+ if ((newnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+ newnmemb > 0 && SIZE_MAX / newnmemb < size) {
+ errno = ENOMEM;
+ return NULL;
+ }
+ newsize = newnmemb * size;
+
+ if ((oldnmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+ oldnmemb > 0 && SIZE_MAX / oldnmemb < size) {
+ errno = EINVAL;
+ return NULL;
+ }
+ oldsize = oldnmemb * size;
+
+ /*
+ * Don't bother too much if we're shrinking just a bit,
+ * we do not shrink for series of small steps, oh well.
+ */
+ if (newsize <= oldsize) {
+ size_t d = oldsize - newsize;
+
+ if (d < oldsize / 2 && d < getpagesize()) {
+ memset((char *)ptr + newsize, 0, d);
+ return ptr;
+ }
+ }
+
+ newptr = malloc(newsize);
+ if (newptr == NULL)
+ return NULL;
+
+ if (newsize > oldsize) {
+ memcpy(newptr, ptr, oldsize);
+ memset((char *)newptr + oldsize, 0, newsize - oldsize);
+ } else
+ memcpy(newptr, ptr, newsize);
+
+ explicit_bzero(ptr, oldsize);
+ free(ptr);
+
+ return newptr;
+}
+/* DEF_WEAK(recallocarray); */
+
+#endif /* HAVE_RECALLOCARRAY */