archive_write_open_memory.c revision 368708 
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: stable/10/contrib/libarchive/libarchive/archive_write_open_memory.c 368708 2020-12-16 22:25:40Z 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_free(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 *)calloc(1, sizeof(*mine));
57	if (mine == NULL) {
58		archive_set_error(a, ENOMEM, "No memory");
59		return (ARCHIVE_FATAL);
60	}
61	mine->buff = buff;
62	mine->size = buffSize;
63	mine->client_size = used;
64	return (archive_write_open2(a, mine,
65		    memory_write_open, memory_write, NULL, memory_write_free));
66}
67
68static int
69memory_write_open(struct archive *a, void *client_data)
70{
71	struct write_memory_data *mine;
72	mine = client_data;
73	mine->used = 0;
74	if (mine->client_size != NULL)
75		*mine->client_size = mine->used;
76	/* Disable padding if it hasn't been set explicitly. */
77	if (-1 == archive_write_get_bytes_in_last_block(a))
78		archive_write_set_bytes_in_last_block(a, 1);
79	return (ARCHIVE_OK);
80}
81
82/*
83 * Copy the data into the client buffer.
84 * Note that we update mine->client_size on every write.
85 * In particular, this means the client can follow exactly
86 * how much has been written into their buffer at any time.
87 */
88static ssize_t
89memory_write(struct archive *a, void *client_data, const void *buff, size_t length)
90{
91	struct write_memory_data *mine;
92	mine = client_data;
93
94	if (mine->used + length > mine->size) {
95		archive_set_error(a, ENOMEM, "Buffer exhausted");
96		return (ARCHIVE_FATAL);
97	}
98	memcpy(mine->buff + mine->used, buff, length);
99	mine->used += length;
100	if (mine->client_size != NULL)
101		*mine->client_size = mine->used;
102	return (length);
103}
104
105static int
106memory_write_free(struct archive *a, void *client_data)
107{
108	struct write_memory_data *mine;
109	(void)a; /* UNUSED */
110	mine = client_data;
111	if (mine == NULL)
112		return (ARCHIVE_OK);
113	free(mine);
114	return (ARCHIVE_OK);
115}
116