diff options
Diffstat (limited to 'tools/patch-image/src/patch-dtb.c')
-rw-r--r-- | tools/patch-image/src/patch-dtb.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/tools/patch-image/src/patch-dtb.c b/tools/patch-image/src/patch-dtb.c new file mode 100644 index 0000000..161e1dc --- /dev/null +++ b/tools/patch-image/src/patch-dtb.c @@ -0,0 +1,101 @@ +/* + * patch-dtb.c - patch a dtb into an image + * + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org> + * Copyright (C) 2012 John Crispin <blogic@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. + * + * based on patch-cmdline.c + */ + +#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 DTB_MAX (16 * 1024) + +int main(int argc, char **argv) +{ + int fd, fddtb, found = 0, len, ret = -1; + char *ptr, *ptrdtb, *p; + struct stat s; + + if (argc != 3) { + fprintf(stderr, "Usage: %s <file> <dtb>\n", argv[0]); + goto err1; + } + fddtb = open(argv[1], O_RDONLY); + if (!fddtb) + goto err1; + + if (stat(argv[2], &s)) { + fprintf(stderr, "DTB not found\n"); + goto err1; + } + + len = s.st_size; + if (len + 8 > DTB_MAX) { + fprintf(stderr, "DTB too big\n"); + goto err1; + } + + if (((fddtb = open(argv[2], O_RDONLY)) < 0) || + (ptrdtb = (char *) mmap(0, DTB_MAX, PROT_READ, MAP_SHARED, fddtb, 0)) == (void *) (-1)) { + fprintf(stderr, "Could not open DTB"); + goto err2; + } + + if (((fd = open(argv[1], O_RDWR)) < 0) || + (ptr = (char *) mmap(0, SEARCH_SPACE + DTB_MAX, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == (void *) (-1)) { + fprintf(stderr, "Could not open kernel image"); + goto err3; + } + + for (p = ptr; p < (ptr + SEARCH_SPACE); p += 4) { + if (memcmp(p, "OWRTDTB:", 8) == 0) { + found = 1; + p += 8; + break; + } + } + if (!found) { + fprintf(stderr, "DTB marker not found!\n"); + goto err4; + } + + memset(p, 0, DTB_MAX - 8); + memcpy(p, ptrdtb, len); + msync(p, len, MS_SYNC|MS_INVALIDATE); + ret = 0; + +err4: + munmap((void *) ptr, len); +err3: + if (fd > 0) + close(fd); + munmap((void *) ptrdtb, len); +err2: + if (fddtb > 0) + close(fddtb); +err1: + return ret; +} |