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 <libgen.h>
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41 #include <sys/mman.h>
  42
  43 #include "compiler.h"
  44 #include <u-boot/crc.h>
  45 #include <version.h>
  46
  47 #define CRC_SIZE sizeof(uint32_t)
  48
  49 static void usage(const char *exec_name)
  50 {
  51         fprintf(stderr, "%s [-h] [-r] [-b] [-p <byte>] -s <environment partition size> -o <output> <input file>\n"
  52                "\n"
  53                "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"
  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 0xff bytes\n"
  62                "\t-V : print version information and exit\n"
  63                "\n"
  64                "If the input file is \"-\", data is read from standard input\n",
  65                exec_name);
  66 }
  67
  68 long int xstrtol(const char *s)
  69 {
  70         long int tmp;
  71
  72         errno = 0;
  73         tmp = strtol(s, NULL, 0);
  74         if (!errno)
  75                 return tmp;
  76
  77         if (errno == ERANGE)
  78                 fprintf(stderr, "Bad integer format: %s\n",  s);
  79         else
  80                 fprintf(stderr, "Error while parsing %s: %s\n", s,
  81                                 strerror(errno));
  82
  83         exit(EXIT_FAILURE);
  84 }
  85
  86 int main(int argc, char **argv)
  87 {
  88         uint32_t crc, targetendian_crc;
  89         const char *txt_filename = NULL, *bin_filename = NULL;
  90         int txt_fd, bin_fd;
  91         unsigned char *dataptr, *envptr;
  92         unsigned char *filebuf = NULL;
  93         unsigned int filesize = 0, envsize = 0, datasize = 0;
  94         int bigendian = 0;
  95         int redundant = 0;
  96         unsigned char padbyte = 0xff;
  97
  98         int option;
  99         int ret = EXIT_SUCCESS;
 100
 101         struct stat txt_file_stat;
 102
 103         int fp, ep;
 104         const char *prg;
 105
 106         prg = basename(argv[0]);
 107
 108         /* Turn off getopt()'s internal error message */
 109         opterr = 0;
 110
 111         /* Parse the cmdline */
 112         while ((option = getopt(argc, argv, ":s:o:rbp:hV")) != -1) {
 113                 switch (option) {
 114                 case 's':
 115                         datasize = xstrtol(optarg);
 116                         break;
 117                 case 'o':
 118                         bin_filename = strdup(optarg);
 119                         if (!bin_filename) {
 120                                 fprintf(stderr, "Can't strdup() the output filename\n");
 121                                 return EXIT_FAILURE;
 122                         }
 123                         break;
 124                 case 'r':
 125                         redundant = 1;
 126                         break;
 127                 case 'b':
 128                         bigendian = 1;
 129                         break;
 130                 case 'p':
 131                         padbyte = xstrtol(optarg);
 132                         break;
 133                 case 'h':
 134                         usage(prg);
 135                         return EXIT_SUCCESS;
 136                 case 'V':
 137                         printf("%s version %s\n", prg, PLAIN_VERSION);
 138                         return EXIT_SUCCESS;
 139                 case ':':
 140                         fprintf(stderr, "Missing argument for option -%c\n",
 141                                 optopt);
 142                         usage(prg);
 143                         return EXIT_FAILURE;
 144                 default:
 145                         fprintf(stderr, "Wrong option -%c\n", optopt);
 146                         usage(prg);
 147                         return EXIT_FAILURE;
 148                 }
 149         }
 150
 151         /* Check datasize and allocate the data */
 152         if (datasize == 0) {
 153                 fprintf(stderr, "Please specify the size of the environment partition.\n");
 154                 usage(prg);
 155                 return EXIT_FAILURE;
 156         }
 157
 158         dataptr = malloc(datasize * sizeof(*dataptr));
 159         if (!dataptr) {
 160                 fprintf(stderr, "Can't alloc %d bytes for dataptr.\n",
 161                                 datasize);
 162                 return EXIT_FAILURE;
 163         }
 164
 165         /*
 166          * envptr points to the beginning of the actual environment (after the
 167          * crc and possible `redundant' byte
 168          */
 169         envsize = datasize - (CRC_SIZE + redundant);
 170         envptr = dataptr + CRC_SIZE + redundant;
 171
 172         /* Pad the environment with the padding byte */
 173         memset(envptr, padbyte, envsize);
 174
 175         /* Open the input file ... */
 176         if (optind >= argc || strcmp(argv[optind], "-") == 0) {
 177                 int readbytes = 0;
 178                 int readlen = sizeof(*envptr) * 4096;
 179                 txt_fd = STDIN_FILENO;
 180
 181                 do {
 182                         filebuf = realloc(filebuf, readlen);
 183                         if (!filebuf) {
 184                                 fprintf(stderr, "Can't realloc memory for the input file buffer\n");
 185                                 return EXIT_FAILURE;
 186                         }
 187                         readbytes = read(txt_fd, filebuf + filesize, readlen);
 188                         if (errno) {
 189                                 fprintf(stderr, "Error while reading stdin: %s\n",
 190                                                 strerror(errno));
 191                                 return EXIT_FAILURE;
 192                         }
 193                         filesize += readbytes;
 194                 } while (readbytes == readlen);
 195
 196         } else {
 197                 txt_filename = argv[optind];
 198                 txt_fd = open(txt_filename, O_RDONLY);
 199                 if (txt_fd == -1) {
 200                         fprintf(stderr, "Can't open \"%s\": %s\n",
 201                                         txt_filename, strerror(errno));
 202                         return EXIT_FAILURE;
 203                 }
 204                 /* ... and check it */
 205                 ret = fstat(txt_fd, &txt_file_stat);
 206                 if (ret == -1) {
 207                         fprintf(stderr, "Can't stat() on \"%s\": %s\n",
 208                                         txt_filename, strerror(errno));
 209                         return EXIT_FAILURE;
 210                 }
 211
 212                 filesize = txt_file_stat.st_size;
 213
 214                 filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
 215                                MAP_PRIVATE, txt_fd, 0);
 216                 if (filebuf == MAP_FAILED) {
 217                         fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
 218                                         sizeof(*envptr) * filesize,
 219                                         strerror(errno));
 220                         fprintf(stderr, "Falling back to read()\n");
 221
 222                         filebuf = malloc(sizeof(*envptr) * filesize);
 223                         ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
 224                         if (ret != sizeof(*envptr) * filesize) {
 225                                 fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
 226                                         sizeof(*envptr) * filesize,
 227                                         strerror(errno));
 228
 229                                 return EXIT_FAILURE;
 230                         }
 231                 }
 232                 ret = close(txt_fd);
 233         }
 234         /* The +1 is for the additionnal ending \0. See below. */
 235         if (filesize + 1 > envsize) {
 236                 fprintf(stderr, "The input file is larger than the environment partition size\n");
 237                 return EXIT_FAILURE;
 238         }
 239
 240         /* Replace newlines separating variables with \0 */
 241         for (fp = 0, ep = 0 ; fp < filesize ; fp++) {
 242                 if (filebuf[fp] == '\n') {
 243                         if (ep == 0) {
 244                                 /*
 245                                  * Newlines at the beginning of the file ?
 246                                  * Ignore them.
 247                                  */
 248                                 continue;
 249                         } else if (filebuf[fp-1] == '\\') {
 250                                 /*
 251                                  * Embedded newline in a variable.
 252                                  *
 253                                  * The backslash was added to the envptr; rewind
 254                                  * and replace it with a newline
 255                                  */
 256                                 ep--;
 257                                 envptr[ep++] = '\n';
 258                         } else {
 259                                 /* End of a variable */
 260                                 envptr[ep++] = '\0';
 261                         }
 262                 } else {
 263                         envptr[ep++] = filebuf[fp];
 264                 }
 265         }
 266         /*
 267          * Make sure there is a final '\0'
 268          * And do it again on the next byte to mark the end of the environment.
 269          */
 270         if (envptr[ep-1] != '\0') {
 271                 envptr[ep++] = '\0';
 272                 /*
 273                  * The text file doesn't have an ending newline.  We need to
 274                  * check the env size again to make sure we have room for two \0
 275                  */
 276                 if (ep >= envsize) {
 277                         fprintf(stderr, "The environment file is too large for the target environment storage\n");
 278                         return EXIT_FAILURE;
 279                 }
 280                 envptr[ep] = '\0';
 281         } else {
 282                 envptr[ep] = '\0';
 283         }
 284
 285         /* Computes the CRC and put it at the beginning of the data */
 286         crc = crc32(0, envptr, envsize);
 287         targetendian_crc = bigendian ? cpu_to_be32(crc) : cpu_to_le32(crc);
 288
 289         memcpy(dataptr, &targetendian_crc, sizeof(targetendian_crc));
 290         if (redundant)
 291                 dataptr[sizeof(targetendian_crc)] = 1;
 292
 293         if (!bin_filename || strcmp(bin_filename, "-") == 0) {
 294                 bin_fd = STDOUT_FILENO;
 295         } else {
 296                 bin_fd = creat(bin_filename, S_IRUSR | S_IWUSR | S_IRGRP |
 297                                              S_IWGRP);
 298                 if (bin_fd == -1) {
 299                         fprintf(stderr, "Can't open output file \"%s\": %s\n",
 300                                         bin_filename, strerror(errno));
 301                         return EXIT_FAILURE;
 302                 }
 303         }
 304
 305         if (write(bin_fd, dataptr, sizeof(*dataptr) * datasize) !=
 306                         sizeof(*dataptr) * datasize) {
 307                 fprintf(stderr, "write() failed: %s\n", strerror(errno));
 308                 return EXIT_FAILURE;
 309         }
 310
 311         ret = close(bin_fd);
 312
 313         return ret;
 314 }