summaryrefslogtreecommitdiff
path: root/tools/mkenvimage.c
blob: a8eebab6c33aa5265002f430d8caa11186e7e4f6 (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
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2011 Free Electrons
 * David Wagner <david.wagner@free-electrons.com>
 *
 * Inspired from envcrc.c:
 * (C) Copyright 2001
 * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
 */

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <libgen.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>

#include "compiler.h"
#include <u-boot/crc.h>
#include <version.h>

#define CRC_SIZE sizeof(uint32_t)

static void usage(const char *exec_name)
{
	fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
	       "\n"
	       "This tool takes a key=value input file (same as would a `printenv' show) and generates the corresponding environment image, ready to be flashed.\n"
	       "\n"
	       "\tThe input file is in format:\n"
	       "\t\tkey1=value1\n"
	       "\t\tkey2=value2\n"
	       "\t\t...\n"
	       "\tEmpty lines are skipped, and lines with a # in the first\n"
	       "\tcolumn are treated as comments (also skipped).\n"
	       "\t-r : the environment has multiple copies in flash\n"
	       "\t-b : the target is big endian (default is little endian)\n"
	       "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
	       "\t-V : print version information and exit\n"
	       "\n"
	       "If the input file is \"-\", data is read from standard input\n",
	       exec_name);
}

long int xstrtol(const char *s)
{
	long int tmp;

	errno = 0;
	tmp = strtol(s, NULL, 0);
	if (!errno)
		return tmp;

	if (errno == ERANGE)
		fprintf(stderr, "Bad integer format: %s\n",  s);
	else
		fprintf(stderr, "Error while parsing %s: %s\n", s,
				strerror(errno));

	exit(EXIT_FAILURE);
}

#define CHUNK_SIZE 4096

int main(int argc, char **argv)
{
	uint32_t crc, targetendian_crc;
	const char *bin_filename = NULL;
	int txt_fd, bin_fd;
	unsigned char *dataptr, *envptr;
	unsigned char *filebuf = NULL;
	unsigned int filesize = 0, envsize = 0, datasize = 0;
	int bigendian = 0;
	int redundant = 0;
	unsigned char padbyte = 0xff;
	int readbytes = 0;

	int option;
	int ret = EXIT_SUCCESS;

	int fp, ep;
	const char *prg;

	prg = basename(argv[0]);

	/* Turn off getopt()'s internal error message */
	opterr = 0;

	/* Parse the cmdline */
	while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
		switch (option) {
		case 's':
			datasize = xstrtol(optarg);
			break;
		case 'o':
			bin_filename = strdup(optarg);
			if (!bin_filename) {
				fprintf(stderr, "Can't strdup() the output filename\n");
				return EXIT_FAILURE;
			}
			break;
		case 'r':
			redundant = 1;
			break;
		case 'b':
			bigendian = 1;
			break;
		case 'p':
			padbyte = xstrtol(optarg);
			break;
		case 'h':
			usage(prg);
			return EXIT_SUCCESS;
		case 'V':
			printf("%s version %s\n", prg, PLAIN_VERSION);
			return EXIT_SUCCESS;
		case ':':
			fprintf(stderr, "Missing argument for option -%c\n",
				optopt);
			usage(prg);
			return EXIT_FAILURE;
		default:
			fprintf(stderr, "Wrong option -%c\n", optopt);
			usage(prg);
			return EXIT_FAILURE;
		}
	}

	/* Check datasize and allocate the data */
	if (datasize == 0) {
		fprintf(stderr, "Please specify the size of the environment partition.\n");
		usage(prg);
		return EXIT_FAILURE;
	}

	dataptr = malloc(datasize * sizeof(*dataptr));
	if (!dataptr) {
		fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
				datasize);
		return EXIT_FAILURE;
	}

	/*
	 * envptr points to the beginning of the actual environment (after the
	 * crc and possible `redundant' byte
	 */
	envsize = datasize - (CRC_SIZE + redundant);
	envptr = dataptr + CRC_SIZE + redundant;

	/* Pad the environment with the padding byte */
	memset(envptr, padbyte, envsize);

	/* Open the input file ... */
	if (optind >= argc || strcmp(argv[optind], "-") == 0) {
		txt_fd = STDIN_FILENO;
	} else {
		txt_fd = open(argv[optind], O_RDONLY);
		if (txt_fd == -1) {
			fprintf(stderr, "Can't open \"%s\": %s\n",
					argv[optind], strerror(errno));
			return EXIT_FAILURE;
		}
	}

	do {
		filebuf = realloc(filebuf, filesize + CHUNK_SIZE);
		if (!filebuf) {
			fprintf(stderr, "Can't realloc memory for the input file buffer\n");
			return EXIT_FAILURE;
		}
		readbytes = read(txt_fd, filebuf + filesize, CHUNK_SIZE);
		if (readbytes < 0) {
			fprintf(stderr, "Error while reading: %s\n",
				strerror(errno));
			return EXIT_FAILURE;
		}
		filesize += readbytes;
	} while (readbytes > 0);

	if (txt_fd != STDIN_FILENO)
		ret = close(txt_fd);

	/* Parse a byte at time until reaching the file OR until the environment fills
	 * up. Check ep against envsize - 1 to allow for extra trailing '\0'. */
	for (fp = 0, ep = 0 ; fp < filesize && ep < envsize - 1; fp++) {
		if (filebuf[fp] == '\n') {
			if (fp == 0 || filebuf[fp-1] == '\n') {
				/*
				 * Skip empty lines.
				 */
				continue;
			} else if (filebuf[fp-1] == '\\') {
				/*
				 * Embedded newline in a variable.
				 *
				 * The backslash was added to the envptr; rewind
				 * and replace it with a newline
				 */
				ep--;
				envptr[ep++] = '\n';
			} else {
				/* End of a variable */
				envptr[ep++] = '\0';
			}
		} else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
			/* Comment, skip the line. */
			while (++fp < filesize && filebuf[fp] != '\n')
			continue;
		} else {
			envptr[ep++] = filebuf[fp];
		}
	}
	/* If there are more bytes in the file still, it means the env filled up
	 * before parsing the whole file.  Eat comments & whitespace here to see if
	 * there was anything meaning full left in the file, and if so, throw a error
	 * and exit. */
	for( ; fp < filesize; fp++ )
	{
		if (filebuf[fp] == '\n') {
			if (fp == 0 || filebuf[fp-1] == '\n') {
				/* Ignore blank lines */
				continue;
			}
		} else if ((fp == 0 || filebuf[fp-1] == '\n') && filebuf[fp] == '#') {
			while (++fp < filesize && filebuf[fp] != '\n')
			continue;
		} else {
			fprintf(stderr, "The environment file is too large for the target environment storage\n");
			return EXIT_FAILURE;
		}
	}
	/*
	 * Make sure there is a final '\0'
	 * And do it again on the next byte to mark the end of the environment.
	 */
	if (envptr[ep-1] != '\0') {
		envptr[ep++] = '\0';
		/*
		 * The text file doesn't have an ending newline.  We need to
		 * check the env size again to make sure we have room for two \0
		 */
		if (ep >= envsize) {
			fprintf(stderr, "The environment file is too large for the target environment storage\n");
			return EXIT_FAILURE;
		}
		envptr[ep] = '\0';
	} else {
		envptr[ep] = '\0';
	}

	/* Computes the CRC and put it at the beginning of the data */
	crc = crc32(0, envptr, envsize);
	targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);

	memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
	if (redundant)
		dataptr[sizeof(targetendian_crc)] = 1;

	if (!bin_filename || strcmp(bin_filename, "-") == 0) {
		bin_fd = STDOUT_FILENO;
	} else {
		bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
					     S_IWGRP);
		if (bin_fd == -1) {
			fprintf(stderr, "Can't open output file \"%s\": %s\n",
					bin_filename, strerror(errno));
			return EXIT_FAILURE;
		}
	}

	if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
			sizeof(*dataptr) * datasize) {
		fprintf(stderr, "write() failed: %s\n", strerror(errno));
		return EXIT_FAILURE;
	}

	ret = close(bin_fd);

	return ret;
}