image.c revision 268236 
1/*-
2 * Copyright (c) 2014 Juniper Networks, Inc.
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 AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/usr.bin/mkimg/image.c 268236 2014-07-03 20:31:43Z marcel $");
29
30#include <sys/types.h>
31#include <assert.h>
32#include <errno.h>
33#include <limits.h>
34#include <paths.h>
35#include <stdio.h>
36#include <stdlib.h>
37#include <unistd.h>
38
39#include "image.h"
40#include "mkimg.h"
41
42#define	BUFFER_SIZE	(1024*1024)
43
44static char image_tmpfile[PATH_MAX];
45static int image_fd = -1;
46static lba_t image_size;
47
48static void
49cleanup(void)
50{
51
52	if (image_fd != -1)
53		close(image_fd);
54	unlink(image_tmpfile);
55}
56
57int
58image_copyin(lba_t blk, int fd, uint64_t *sizep)
59{
60	char *buffer;
61	uint64_t bytesize;
62	ssize_t bcnt, rdsz;
63	int error, partial;
64
65	assert(BUFFER_SIZE % secsz == 0);
66
67	buffer = malloc(BUFFER_SIZE);
68	if (buffer == NULL)
69		return (ENOMEM);
70	bytesize = 0;
71	partial = 0;
72	while (1) {
73		rdsz = read(fd, buffer, BUFFER_SIZE);
74		if (rdsz <= 0) {
75			error = (rdsz < 0) ? errno : 0;
76			break;
77		}
78		if (partial)
79			abort();
80		bytesize += rdsz;
81		bcnt = (rdsz + secsz - 1) / secsz;
82		error = image_write(blk, buffer, bcnt);
83		if (error)
84			break;
85		blk += bcnt;
86		partial = ((ssize_t)(bcnt * secsz) != rdsz) ? 1 : 0;
87	}
88	free(buffer);
89	if (sizep != NULL)
90		*sizep = bytesize;
91	return (error);
92}
93
94int
95image_copyout(int fd)
96{
97	off_t ofs;
98	int error;
99
100	error = image_copyout_region(fd, 0, image_size);
101	if (error)
102		return (error);
103
104	ofs = lseek(fd, 0L, SEEK_CUR);
105	if (ofs == -1)
106		return (0);
107	error = (ftruncate(fd, ofs) == -1) ? errno : 0;
108	return (error);
109}
110
111int
112image_copyout_region(int fd, lba_t blk, lba_t size)
113{
114	char *buffer;
115	off_t ofs;
116	size_t sz;
117	ssize_t rdsz, wrsz;
118	int error;
119
120	ofs = lseek(fd, 0L, SEEK_CUR);
121
122	blk *= secsz;
123	if (lseek(image_fd, blk, SEEK_SET) != blk)
124		return (errno);
125	buffer = malloc(BUFFER_SIZE);
126	if (buffer == NULL)
127		return (errno);
128	error = 0;
129	size *= secsz;
130	while (size > 0) {
131		sz = (BUFFER_SIZE < size) ? BUFFER_SIZE : size;
132		rdsz = read(image_fd, buffer, sz);
133		if (rdsz <= 0) {
134			error = (rdsz < 0) ? errno : 0;
135			break;
136		}
137		wrsz = (ofs == -1) ?
138		    write(fd, buffer, rdsz) :
139		    sparse_write(fd, buffer, rdsz);
140		if (wrsz < 0) {
141			error = errno;
142			break;
143		}
144		assert(wrsz == rdsz);
145		size -= rdsz;
146	}
147	free(buffer);
148	return (error);
149}
150
151lba_t
152image_get_size(void)
153{
154
155	return (image_size);
156}
157
158int
159image_set_size(lba_t blk)
160{
161
162	image_size = blk;
163	if (ftruncate(image_fd, blk * secsz) == -1)
164		return (errno);
165	return (0);
166}
167
168int
169image_write(lba_t blk, void *buf, ssize_t len)
170{
171
172	blk *= secsz;
173	if (lseek(image_fd, blk, SEEK_SET) != blk)
174		return (errno);
175	len *= secsz;
176	if (sparse_write(image_fd, buf, len) != len)
177		return (errno);
178	return (0);
179}
180
181int
182image_init(void)
183{
184	const char *tmpdir;
185
186	if (atexit(cleanup) == -1)
187		return (errno);
188	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
189		tmpdir = _PATH_TMP;
190	snprintf(image_tmpfile, sizeof(image_tmpfile), "%s/mkimg-XXXXXX",
191	    tmpdir);
192	image_fd = mkstemp(image_tmpfile);
193	if (image_fd == -1)
194		return (errno);
195	return (0);
196}
197