summaryrefslogtreecommitdiffstats
path: root/gl/lib/malloc/scratch_buffer_grow_preserve.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:37:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:37:10 +0000
commitc9addba5cc770d2d231b34f6739f32c6be8690f1 (patch)
treec643da154a95a1d163137135050bb47858a1654e /gl/lib/malloc/scratch_buffer_grow_preserve.c
parentInitial commit. (diff)
downloadman-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.tar.xz
man-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.zip
Adding upstream version 2.12.0.upstream/2.12.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gl/lib/malloc/scratch_buffer_grow_preserve.c')
-rw-r--r--gl/lib/malloc/scratch_buffer_grow_preserve.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/gl/lib/malloc/scratch_buffer_grow_preserve.c b/gl/lib/malloc/scratch_buffer_grow_preserve.c
new file mode 100644
index 0000000..c0b5d87
--- /dev/null
+++ b/gl/lib/malloc/scratch_buffer_grow_preserve.c
@@ -0,0 +1,67 @@
+/* Variable-sized buffer with on-stack default allocation.
+ Copyright (C) 2015-2023 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
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <scratch_buffer.h>
+#include <errno.h>
+#include <string.h>
+
+bool
+__libc_scratch_buffer_grow_preserve (struct scratch_buffer *buffer)
+{
+ size_t new_length = 2 * buffer->length;
+ void *new_ptr;
+
+ if (buffer->data == buffer->__space.__c)
+ {
+ /* Move buffer to the heap. No overflow is possible because
+ buffer->length describes a small buffer on the stack. */
+ new_ptr = malloc (new_length);
+ if (new_ptr == NULL)
+ return false;
+ memcpy (new_ptr, buffer->__space.__c, buffer->length);
+ }
+ else
+ {
+ /* Buffer was already on the heap. Check for overflow. */
+ if (__glibc_likely (new_length >= buffer->length))
+ new_ptr = realloc (buffer->data, new_length);
+ else
+ {
+ __set_errno (ENOMEM);
+ new_ptr = NULL;
+ }
+
+ if (__glibc_unlikely (new_ptr == NULL))
+ {
+ /* Deallocate, but buffer must remain valid to free. */
+ free (buffer->data);
+ scratch_buffer_init (buffer);
+ return false;
+ }
+ }
+
+ /* Install new heap-based buffer. */
+ buffer->data = new_ptr;
+ buffer->length = new_length;
+ return true;
+}
+libc_hidden_def (__libc_scratch_buffer_grow_preserve)