blob: 4da8fc181e78bb24aeded44d27abb25ca43ca638 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
/* Variable-sized buffer with on-stack default allocation.
Copyright (C) 2015-2019 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 General Public
License as published by the Free Software Foundation; either
version 3 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
General Public License for more details.
You should have received a copy of the GNU 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)
|