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 <stdlib.h>
  35 #include <stdint.h>
  36 #include <string.h>
  37 #include <unistd.h>
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40 #include <sys/mman.h>
  41
  42 #include "compiler.h"
  43 #include <u-boot/crc.h>
  44 #include <version.h>
  45
  46 #define CRC_SIZE sizeof(uint32_t)
  47
  48 static void usage(const char *exec_name)
  49 {
  50         fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
  51                "\n"
  52                "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"
  53                "\n"
  54                "\tThe input file is in format:\n"
  55                "\t\tkey1=value1\n"
  56                "\t\tkey2=value2\n"
  57                "\t\t...\n"
  58                "\t-r : the environment has multiple copies in flash\n"
  59                "\t-b : the target is big endian (default is little endian)\n"
  60                "\t-p <byte> : fill the image with <byte> bytes instead of 0xff bytes\n"
  61                "\t-V : print version information and exit\n"
  62                "\n"
  63                "If the input file is \"-\", data is read from standard input\n",
  64                exec_name);
  65 }
  66
  67 long int xstrtol(const char *s)
  68 {
  69         long int tmp;
  70
  71         errno = 0;
  72         tmp = strtol(s, NULL, 0);
  73         if (!errno)
  74                 return tmp;
  75
  76         if (errno == ERANGE)
  77                 fprintf(stderr, "Bad integer format: %s\n",  s);
  78         else
  79                 fprintf(stderr, "Error while parsing %s: %s\n", s,
  80                                 strerror(errno));
  81
  82         exit(EXIT_FAILURE);
  83 }
  84
  85 int main(int argc, char **argv)
  86 {
  87         uint32_t crc, targetendian_crc;
  88         const char *txt_filename = NULL, *bin_filename = NULL;
  89         int txt_fd, bin_fd;
  90         unsigned char *dataptr, *envptr;
  91         unsigned char *filebuf = NULL;
  92         unsigned int filesize = 0, envsize = 0, datasize = 0;
  93         int bigendian = 0;
  94         int redundant = 0;
  95         unsigned char padbyte = 0xff;
  96
  97         int option;
  98         int ret = EXIT_SUCCESS;
  99
 100         struct stat txt_file_stat;
 101
 102         int fp, ep;
 103         const char *prg;
 104
 105         prg = basename(argv[0]);
 106
 107         /* Turn off getopt()'s internal error message */
 108         opterr = 0;
 109
 110         /* Parse the cmdline */
 111         while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
 112                 switch (option) {
 113                 case 's':
 114                         datasize = xstrtol(optarg);
 115                         break;
 116                 case 'o':
 117                         bin_filename = strdup(optarg);
 118                         if (!bin_filename) {
 119                                 fprintf(stderr, "Can't strdup() the output filename\n");
 120                                 return EXIT_FAILURE;
 121                         }
 122                         break;
 123                 case 'r':
 124                         redundant = 1;
 125                         break;
 126                 case 'b':
 127                         bigendian = 1;
 128                         break;
 129                 case 'p':
 130                         padbyte = xstrtol(optarg);
 131                         break;
 132                 case 'h':
 133                         usage(prg);
 134                         return EXIT_SUCCESS;
 135                 case 'V':
 136                         printf("%s version %s\n", prg, PLAIN_VERSION);
 137                         return EXIT_SUCCESS;
 138                 case ':':
 139                         fprintf(stderr, "Missing argument for option -%c\n",
 140                                 optopt);
 141                         usage(prg);
 142                         return EXIT_FAILURE;
 143                 default:
 144                         fprintf(stderr, "Wrong option -%c\n", optopt);
 145                         usage(prg);
 146                         return EXIT_FAILURE;
 147                 }
 148         }
 149
 150         /* Check datasize and allocate the data */
 151         if (datasize == 0) {
 152                 fprintf(stderr, "Please specify the size of the environment partition.\n");
 153                 usage(prg);
 154                 return EXIT_FAILURE;
 155         }
 156
 157         dataptr = malloc(datasize * sizeof(*dataptr));
 158         if (!dataptr) {
 159                 fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
 160                                 datasize);
 161                 return EXIT_FAILURE;
 162         }
 163
 164         /*
 165          * envptr points to the beginning of the actual environment (after the
 166          * crc and possible `redundant' byte
 167          */
 168         envsize = datasize - (CRC_SIZE + redundant);
 169         envptr = dataptr + CRC_SIZE + redundant;
 170
 171         /* Pad the environment with the padding byte */
 172         memset(envptr, padbyte, envsize);
 173
 174         /* Open the input file ... */
 175         if (optind >= argc || strcmp(argv[optind], "-") == 0) {
 176                 int readbytes = 0;
 177                 int readlen = sizeof(*envptr) * 4096;
 178                 txt_fd = STDIN_FILENO;
 179
 180                 do {
 181                         filebuf = realloc(filebuf, readlen);
 182                         if (!filebuf) {
 183                                 fprintf(stderr, "Can't realloc memory for the input file buffer\n");
 184                                 return EXIT_FAILURE;
 185                         }
 186                         readbytes = read(txt_fd, filebuf + filesize, readlen);
 187                         if (errno) {
 188                                 fprintf(stderr, "Error while reading stdin: %s\n",
 189                                                 strerror(errno));
 190                                 return EXIT_FAILURE;
 191                         }
 192                         filesize += readbytes;
 193                 } while (readbytes == readlen);
 194
 195         } else {
 196                 txt_filename = argv[optind];
 197                 txt_fd = open(txt_filename, O_RDONLY);
 198                 if (txt_fd == -1) {
 199                         fprintf(stderr, "Can't open \"%s\": %s\n",
 200                                         txt_filename, strerror(errno));
 201                         return EXIT_FAILURE;
 202                 }
 203                 /* ... and check it */
 204                 ret = fstat(txt_fd, &txt_file_stat);
 205                 if (ret == -1) {
 206                         fprintf(stderr, "Can't stat() on \"%s\": %s\n",
 207                                         txt_filename, strerror(errno));
 208                         return EXIT_FAILURE;
 209                 }
 210
 211                 filesize = txt_file_stat.st_size;
 212
 213                 filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
 214                                MAP_PRIVATE, txt_fd, 0);
 215                 if (filebuf == MAP_FAILED) {
 216                         fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
 217                                         sizeof(*envptr) * filesize,
 218                                         strerror(errno));
 219                         fprintf(stderr, "Falling back to read()\n");
 220
 221                         filebuf = malloc(sizeof(*envptr) * filesize);
 222                         ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
 223                         if (ret != sizeof(*envptr) * filesize) {
 224                                 fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
 225                                         sizeof(*envptr) * filesize,
 226                                         strerror(errno));
 227
 228                                 return EXIT_FAILURE;
 229                         }
 230                 }
 231                 ret = close(txt_fd);
 232         }
 233         /* The +1 is for the additionnal ending \0. See below. */
 234         if (filesize + 1 > envsize) {
 235                 fprintf(stderr, "The input file is larger than the environment partition size\n");
 236                 return EXIT_FAILURE;
 237         }
 238
 239         /* Replace newlines separating variables with \0 */
 240         for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
 241                 if (filebuf[fp] == '\n') {
 242                         if (ep == 0) {
 243                                 /*
 244                                  * Newlines at the beginning of the file ?
 245                                  * Ignore them.
 246                                  */
 247                                 continue;
 248                         } else if (filebuf[fp-1] == '\\') {
 249                                 /*
 250                                  * Embedded newline in a variable.
 251                                  *
 252                                  * The backslash was added to the envptr; rewind
 253                                  * and replace it with a newline
 254                                  */
 255                                 ep--;
 256                                 envptr[ep++] = '\n';
 257                         } else {
 258                                 /* End of a variable */
 259                                 envptr[ep++] = '\0';
 260                         }
 261                 } else {
 262                         envptr[ep++] = filebuf[fp];
 263                 }
 264         }
 265         /*
 266          * Make sure there is a final '\0'
 267          * And do it again on the next byte to mark the end of the environment.
 268          */
 269         if (envptr[ep-1] != '\0') {
 270                 envptr[ep++] = '\0';
 271                 /*
 272                  * The text file doesn't have an ending newline.  We need to
 273                  * check the env size again to make sure we have room for two \0
 274                  */
 275                 if (ep >= envsize) {
 276                         fprintf(stderr, "The environment file is too large for the target environment storage\n");
 277                         return EXIT_FAILURE;
 278                 }
 279                 envptr[ep] = '\0';
 280         } else {
 281                 envptr[ep] = '\0';
 282         }
 283
 284         /* Computes the CRC and put it at the beginning of the data */
 285         crc = crc32(0, envptr, envsize);
 286         targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
 287
 288         memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
 289         if (redundant)
 290                 dataptr[sizeof(targetendian_crc)] = 1;
 291
 292         if (!bin_filename || strcmp(bin_filename, "-") == 0) {
 293                 bin_fd = STDOUT_FILENO;
 294         } else {
 295                 bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
 296                                              S_IWGRP);
 297                 if (bin_fd == -1) {
 298                         fprintf(stderr, "Can't open output file \"%s\": %s\n",
 299                                         bin_filename, strerror(errno));
 300                         return EXIT_FAILURE;
 301                 }
 302         }
 303
 304         if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
 305                         sizeof(*dataptr) * datasize) {
 306                 fprintf(stderr, "write() failed: %s\n", strerror(errno));
 307                 return EXIT_FAILURE;
 308         }
 309
 310         ret = close(bin_fd);
 311
 312         return ret;
 313 }