archive_write_open_memory.c revision 232153 
1/*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "archive_platform.h"
27__FBSDID("$FreeBSD: head/contrib/libarchive/libarchive/archive_write_open_memory.c 232153 2012-02-25 10:58:02Z mm $");
28
29#include <errno.h>
30#include <stdlib.h>
31#include <string.h>
32
33#include "archive.h"
34
35struct write_memory_data {
36	size_t	used;
37	size_t  size;
38	size_t * client_size;
39	unsigned char * buff;
40};
41
42static int	memory_write_close(struct archive *, void *);
43static int	memory_write_open(struct archive *, void *);
44static ssize_t	memory_write(struct archive *, void *, const void *buff, size_t);
45
46/*
47 * Client provides a pointer to a block of memory to receive
48 * the data.  The 'size' param both tells us the size of the
49 * client buffer and lets us tell the client the final size.
50 */
51int
52archive_write_open_memory(struct archive *a, void *buff, size_t buffSize, size_t *used)
53{
54	struct write_memory_data *mine;
55
56	mine = (struct write_memory_data *)malloc(sizeof(*mine));
57	if (mine == NULL) {
58		archive_set_error(a, ENOMEM, "No memory");
59		return (ARCHIVE_FATAL);
60	}
61	memset(mine, 0, sizeof(*mine));
62	mine->buff = buff;
63	mine->size = buffSize;
64	mine->client_size = used;
65	return (archive_write_open(a, mine,
66		    memory_write_open, memory_write, memory_write_close));
67}
68
69static int
70memory_write_open(struct archive *a, void *client_data)
71{
72	struct write_memory_data *mine;
73	mine = client_data;
74	mine->used = 0;
75	if (mine->client_size != NULL)
76		*mine->client_size = mine->used;
77	/* Disable padding if it hasn't been set explicitly. */
78	if (-1 == archive_write_get_bytes_in_last_block(a))
79		archive_write_set_bytes_in_last_block(a, 1);
80	return (ARCHIVE_OK);
81}
82
83/*
84 * Copy the data into the client buffer.
85 * Note that we update mine->client_size on every write.
86 * In particular, this means the client can follow exactly
87 * how much has been written into their buffer at any time.
88 */
89static ssize_t
90memory_write(struct archive *a, void *client_data, const void *buff, size_t length)
91{
92	struct write_memory_data *mine;
93	mine = client_data;
94
95	if (mine->used + length > mine->size) {
96		archive_set_error(a, ENOMEM, "Buffer exhausted");
97		return (ARCHIVE_FATAL);
98	}
99	memcpy(mine->buff + mine->used, buff, length);
100	mine->used += length;
101	if (mine->client_size != NULL)
102		*mine->client_size = mine->used;
103	return (length);
104}
105
106static int
107memory_write_close(struct archive *a, void *client_data)
108{
109	struct write_memory_data *mine;
110	(void)a; /* UNUSED */
111	mine = client_data;
112	free(mine);
113	return (ARCHIVE_OK);
114}
115