tools/mkenvimage.c

   1 /*
   2  * (C) Copyright 2011 Free Electrons
   3  * David Wagner <david.wagner@free-electrons.com>
   4  *
   5  * Inspired from envcrc.c:
   6  * (C) Copyright 2001
   7  * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
   8  *
   9  * See file CREDITS for list of people who contributed to this
  10  * project.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation; either version 2 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  25  * MA 02111-1307 USA
  26  */
  27
  28 /* We want the GNU version of basename() */
  29 #define _GNU_SOURCE
  30
  31 #include <errno.h>
  32 #include <fcntl.h>
  33 #include <stdio.h>
  34 #include <stdint.h>
  35 #include <string.h>
  36 #include <unistd.h>
  37 #include <compiler.h>
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40
  41 #include <u-boot/crc.h>
  42 #include <version.h>
  43
  44 #define CRC_SIZE sizeof(uint32_t)
  45
  46 static void usage(const char *exec_name)
  47 {
  48         fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] "
  49                "-s <environment partition size> -o <output> <input file>\n"
  50                "\n"
  51                "This tool takes a key=value input file (same as would a "
  52                "`printenv' show) and generates the corresponding environment "
  53                "image, ready to be flashed.\n"
  54                "\n"
  55                "\tThe input file is in format:\n"
  56                "\t\tkey1=value1\n"
  57                "\t\tkey2=value2\n"
  58                "\t\t...\n"
  59                "\t-r : the environment has multiple copies in flash\n"
  60                "\t-b : the target is big endian (default is little endian)\n"
  61                "\t-p <byte> : fill the image with <byte> bytes instead of "
  62                "0xff bytes\n"
  63                "\t-V : print version information and exit\n"
  64                "\n"
  65                "If the input file is \"-\", data is read from standard input\n",
  66                exec_name);
  67 }
  68
  69 int main(int argc, char **argv)
  70 {
  71         uint32_t crc, targetendian_crc;
  72         const char *txt_filename = NULL, *bin_filename = NULL;
  73         int txt_fd, bin_fd;
  74         unsigned char *dataptr, *envptr;
  75         unsigned char *filebuf = NULL;
  76         unsigned int filesize = 0, envsize = 0, datasize = 0;
  77         int bigendian = 0;
  78         int redundant = 0;
  79         unsigned char padbyte = 0xff;
  80
  81         int option;
  82         int ret = EXIT_SUCCESS;
  83
  84         struct stat txt_file_stat;
  85
  86         int fp, ep;
  87         const char *prg;
  88
  89         prg = basename(argv[0]);
  90
  91         /* Turn off getopt()'s internal error message */
  92         opterr = 0;
  93
  94         /* Parse the cmdline */
  95         while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
  96                 switch (option) {
  97                 case 's':
  98                         datasize = strtol(optarg, NULL, 0);
  99                         break;
 100                 case 'o':
 101                         bin_filename = strdup(optarg);
 102                         if (!bin_filename) {
 103                                 fprintf(stderr, "Can't strdup() the output "
 104                                                 "filename\n");
 105                                 return EXIT_FAILURE;
 106                         }
 107                         break;
 108                 case 'r':
 109                         redundant = 1;
 110                         break;
 111                 case 'b':
 112                         bigendian = 1;
 113                         break;
 114                 case 'p':
 115                         padbyte = strtol(optarg, NULL, 0);
 116                         break;
 117                 case 'h':
 118                         usage(prg);
 119                         return EXIT_SUCCESS;
 120                 case 'V':
 121                         printf("%s version %s\n", prg, PLAIN_VERSION);
 122                         return EXIT_SUCCESS;
 123                 case ':':
 124                         fprintf(stderr, "Missing argument for option -%c\n",
 125                                 optopt);
 126                         usage(argv[0]);
 127                         return EXIT_FAILURE;
 128                 default:
 129                         fprintf(stderr, "Wrong option -%c\n", optopt);
 130                         usage(prg);
 131                         return EXIT_FAILURE;
 132                 }
 133         }
 134
 135         /* Check datasize and allocate the data */
 136         if (datasize == 0) {
 137                 fprintf(stderr,
 138                         "Please specify the size of the environment "
 139                         "partition.\n");
 140                 usage(prg);
 141                 return EXIT_FAILURE;
 142         }
 143
 144         dataptr = malloc(datasize * sizeof(*dataptr));
 145         if (!dataptr) {
 146                 fprintf(stderr, "Can't alloc dataptr.\n");
 147                 return EXIT_FAILURE;
 148         }
 149
 150         /*
 151          * envptr points to the beginning of the actual environment (after the
 152          * crc and possible `redundant' bit
 153          */
 154         envsize = datasize - (CRC_SIZE + redundant);
 155         envptr = dataptr + CRC_SIZE + redundant;
 156
 157         /* Pad the environment with the padding byte */
 158         memset(envptr, padbyte, envsize);
 159
 160         /* Open the input file ... */
 161         if (optind >= argc) {
 162                 fprintf(stderr, "Please specify an input filename\n");
 163                 return EXIT_FAILURE;
 164         }
 165
 166         txt_filename = argv[optind];
 167         if (strcmp(txt_filename, "-") == 0) {
 168                 int readbytes = 0;
 169                 int readlen = sizeof(*envptr) * 2048;
 170                 txt_fd = STDIN_FILENO;
 171
 172                 do {
 173                         filebuf = realloc(filebuf, readlen);
 174                         readbytes = read(txt_fd, filebuf + filesize, readlen);
 175                         filesize += readbytes;
 176                 } while (readbytes == readlen);
 177
 178         } else {
 179                 txt_fd = open(txt_filename, O_RDONLY);
 180                 if (txt_fd == -1) {
 181                         fprintf(stderr, "Can't open \"%s\": %s\n",
 182                                         txt_filename, strerror(errno));
 183                         return EXIT_FAILURE;
 184                 }
 185                 /* ... and check it */
 186                 ret = fstat(txt_fd, &txt_file_stat);
 187                 if (ret == -1) {
 188                         fprintf(stderr, "Can't stat() on \"%s\": "
 189                                         "%s\n", txt_filename, strerror(errno));
 190                         return EXIT_FAILURE;
 191                 }
 192
 193                 filesize = txt_file_stat.st_size;
 194                 /* Read the raw input file and transform it */
 195                 filebuf = malloc(sizeof(*envptr) * filesize);
 196                 ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
 197                 if (ret != sizeof(*envptr) * filesize) {
 198                         fprintf(stderr, "Can't read the whole input file\n");
 199                         return EXIT_FAILURE;
 200                 }
 201                 ret = close(txt_fd);
 202         }
 203         /*
 204          * The right test to do is "=>" (not ">") because of the additional
 205          * ending \0. See below.
 206          */
 207         if (filesize >= envsize) {
 208                 fprintf(stderr, "The input file is larger than the "
 209                                 "environment partition size\n");
 210                 return EXIT_FAILURE;
 211         }
 212
 213         /* Replace newlines separating variables with \0 */
 214         for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
 215                 if (filebuf[fp] == '\n') {
 216                         if (fp == 0) {
 217                                 /*
 218                                  * Newline at the beginning of the file ?
 219                                  * Ignore it.
 220                                  */
 221                                 continue;
 222                         } else if (filebuf[fp-1] == '\\') {
 223                                 /*
 224                                  * Embedded newline in a variable.
 225                                  *
 226                                  * The backslash was added to the envptr ;
 227                                  * rewind and replace it with a newline
 228                                  */
 229                                 ep--;
 230                                 envptr[ep++] = '\n';
 231                         } else {
 232                                 /* End of a variable */
 233                                 envptr[ep++] = '\0';
 234                         }
 235                 } else if (filebuf[fp] == '#') {
 236                         if (fp != 0 && filebuf[fp-1] == '\n') {
 237                                 /* This line is a comment, let's skip it */
 238                                 while (fp < txt_file_stat.st_size && fp++ &&
 239                                        filebuf[fp] != '\n');
 240                         } else {
 241                                 envptr[ep++] = filebuf[fp];
 242                         }
 243                 } else {
 244                         envptr[ep++] = filebuf[fp];
 245                 }
 246         }
 247         /*
 248          * Make sure there is a final '\0'
 249          * And do it again on the next byte to mark the end of the environment.
 250          */
 251         if (envptr[ep-1] != '\0') {
 252                 envptr[ep++] = '\0';
 253                 /*
 254                  * The text file doesn't have an ending newline.  We need to
 255                  * check the env size again to make sure we have room for two \0
 256                  */
 257                 if (ep >= envsize) {
 258                         fprintf(stderr, "The environment file is too large for "
 259                                         "the target environment storage\n");
 260                         return EXIT_FAILURE;
 261                 }
 262                 envptr[ep] = '\0';
 263         } else {
 264                 envptr[ep] = '\0';
 265         }
 266
 267         /* Computes the CRC and put it at the beginning of the data */
 268         crc = crc32(0, envptr, envsize);
 269         targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
 270
 271         memcpy(dataptr, &targetendian_crc, sizeof(uint32_t));
 272
 273         bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
 274         if (bin_fd == -1) {
 275                 fprintf(stderr, "Can't open output file \"%s\": %s\n",
 276                                 bin_filename, strerror(errno));
 277                 return EXIT_FAILURE;
 278         }
 279
 280         if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
 281                         sizeof(*dataptr) * datasize) {
 282                 fprintf(stderr, "write() failed: %s\n", strerror(errno));
 283                 return EXIT_FAILURE;
 284         }
 285
 286         ret = close(bin_fd);
 287
 288         return ret;
 289 }