Jetpack/u-boot/tools/mkenvimage.c

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/*
* (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
*
* SPDX-License-Identifier: GPL-2.0+
*/
#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);
}
int main(int argc, char **argv)
{
uint32_t crc, targetendian_crc;
const char *txt_filename = NULL, *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 option;
int ret = EXIT_SUCCESS;
struct stat txt_file_stat;
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) {
int readbytes = 0;
int readlen = sizeof(*envptr) * 4096;
txt_fd = STDIN_FILENO;
do {
filebuf = realloc(filebuf, readlen);
if (!filebuf) {
fprintf(stderr, "Can't realloc memory for the input file buffer\n");
return EXIT_FAILURE;
}
readbytes = read(txt_fd, filebuf + filesize, readlen);
if (errno) {
fprintf(stderr, "Error while reading stdin: %s\n",
strerror(errno));
return EXIT_FAILURE;
}
filesize += readbytes;
} while (readbytes == readlen);
} else {
txt_filename = argv[optind];
txt_fd = open(txt_filename, O_RDONLY);
if (txt_fd == -1) {
fprintf(stderr, "Can't open \"%s\": %s\n",
txt_filename, strerror(errno));
return EXIT_FAILURE;
}
/* ... and check it */
ret = fstat(txt_fd, &txt_file_stat);
if (ret == -1) {
fprintf(stderr, "Can't stat() on \"%s\": %s\n",
txt_filename, strerror(errno));
return EXIT_FAILURE;
}
filesize = txt_file_stat.st_size;
filebuf = mmap(NULL, sizeof(*envptr) * filesize, PROT_READ,
MAP_PRIVATE, txt_fd, 0);
if (filebuf == MAP_FAILED) {
fprintf(stderr, "mmap (%zu bytes) failed: %s\n",
sizeof(*envptr) * filesize,
strerror(errno));
fprintf(stderr, "Falling back to read()\n");
filebuf = malloc(sizeof(*envptr) * filesize);
ret = read(txt_fd, filebuf, sizeof(*envptr) * filesize);
if (ret != sizeof(*envptr) * filesize) {
fprintf(stderr, "Can't read the whole input file (%zu bytes): %s\n",
sizeof(*envptr) * filesize,
strerror(errno));
return EXIT_FAILURE;
}
}
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;
}