diff options
Diffstat (limited to 'tools/patch-image/src/patch-cmdline.c')
-rw-r--r-- | tools/patch-image/src/patch-cmdline.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/tools/patch-image/src/patch-cmdline.c b/tools/patch-image/src/patch-cmdline.c new file mode 100644 index 0000000..571f848 --- /dev/null +++ b/tools/patch-image/src/patch-cmdline.c @@ -0,0 +1,79 @@ +/* + * patch-cmdline.c - patch the kernel command line on rb532 + * + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stddef.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <string.h> + +#define SEARCH_SPACE (16 * 1024) +#define CMDLINE_MAX 512 + +int main(int argc, char **argv) +{ + int fd, found = 0, len, ret = -1; + char *ptr, *p; + + if (argc != 3) { + fprintf(stderr, "Usage: %s <file> <cmdline>\n", argv[0]); + goto err1; + } + len = strlen(argv[2]); + if (len + 9 > CMDLINE_MAX) { + fprintf(stderr, "Command line string too long\n"); + goto err1; + } + + if (((fd = open(argv[1], O_RDWR)) < 0) || + (ptr = (char *) mmap(0, SEARCH_SPACE + CMDLINE_MAX, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == (void *) (-1)) { + fprintf(stderr, "Could not open kernel image"); + goto err2; + } + + for (p = ptr; p < (ptr + SEARCH_SPACE); p += 4) { + if (memcmp(p, "CMDLINE:", 8) == 0) { + found = 1; + p += 8; + break; + } + } + if (!found) { + fprintf(stderr, "Command line marker not found!\n"); + goto err3; + } + + memset(p, 0, CMDLINE_MAX - 8); + strcpy(p, argv[2]); + msync(p, CMDLINE_MAX, MS_SYNC|MS_INVALIDATE); + ret = 0; + +err3: + munmap((void *) ptr, len); +err2: + if (fd > 0) + close(fd); +err1: + return ret; +} |