| @@ -0,0 +1,185 @@
+/* $Id: mkzimage_cmdline.c 590 2006-02-07 14:38:07Z jplack $ */
+/*
+ * a little tool to modify the cmdline inside a zImage
+ * Olaf Hering <olh@suse.de> Copyright (C) 2003, 2004
+ */
+
+/*
+ 2003-10-02, version 1
+ 2003-11-15, version 2: fix short reads if the string is at the end of the file
+ 2004-08-07, version 3: use mmap
+ */
+/*
+ * 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
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+#define MY_VERSION 3
+
+static int activate;
+static int clear;
+static int set;
+static char *string;
+static char *filename;
+
+static const char cmdline_start[] = "cmd_line_start";
+static const char cmdline_end[] = "cmd_line_end";
+
+static void my_version(void)
+{
+ printf("version: %d\n", MY_VERSION);
+ printf("(C) SuSE Linux AG, Nuernberg, Germany, 2003, 2004\n");
+ return;
+}
+
+static void my_rtfm(const char *app)
+{
+ printf("modify the built-in cmdline of a CHRP boot image\n");
+ printf("%s filename\n", app);
+ printf("work with zImage named 'filename'\n");
+ printf(" [-h] display this help\n");
+ printf(" [-v] display version\n");
+ printf(" [-a 0|1] disable/enable built-in cmdline\n");
+ printf(" overrides whatever is passed from OpenFirmware\n");
+ printf(" [-s STRING] store STRING in the boot image\n");
+ printf(" [-c] clear previous content before update\n");
+ printf(" no option will show the current settings in 'filename'\n");
+ return;
+}
+
+int main(int argc, char **argv)
+{
+ struct stat sb;
+ int fd, found;
+ unsigned char *p, *s, *e, *tmp, *active;
+
+ if (argc < 2) {
+ my_rtfm(argv[0]);
+ exit(1);
+ }
+
+ while (1) {
+ int i;
+ i = getopt(argc, argv, "a:hcvs:");
+ if (i == -1)
+ break;
+ switch (i) {
+ case 'a':
+ if (*optarg == '0')
+ activate = -1;
+ else
+ activate = 1;
+ break;
+ case 'c':
+ clear = 1;
+ break;
+ case 'h':
+ my_rtfm(argv[0]);
+ exit(0);
+ case 's':
+ string = strdup(optarg);
+ if (!string) {
+ fprintf(stderr, "set: no mem\n");
+ exit(1);
+ }
+ set = 1;
+ if (!activate)
+ activate = 1;
+ break;
+ case 'v':
+ my_version();
+ exit(0);
+ default:
+ printf("unknown option\n");
+ my_rtfm(argv[0]);
+ exit(1);
+ }
+ }
+ if (argc <= optind) {
+ fprintf(stderr, "filename required\n");
+ exit(1);
+ }
+ filename = strdup(argv[optind]);
+ if (!filename) {
+ fprintf(stderr, "no mem\n");
+ exit(1);
+ }
+
+ fd = open(filename, (activate || clear || set) ? O_RDWR : O_RDONLY);
+ if (fd == -1)
+ goto error;
+ found = stat(filename, &sb);
+ if (found < 0)
+ goto error;
+ if (!S_ISREG(sb.st_mode)) {
+ fprintf(stderr, "%s is not a file\n", filename);
+ exit(1);
+ }
+
+ p = mmap(NULL, sb.st_size,
+ ((activate || clear || set) ?
+ PROT_WRITE : 0) | PROT_READ, MAP_SHARED, fd, 0);
+ if (p == MAP_FAILED)
+ goto error;
+ s = p;
+ e = p + sb.st_size - sizeof(cmdline_start) - sizeof(cmdline_end);
+ found = 0;
+ while (s < e) {
+ if (memcmp(++s, cmdline_start, sizeof(cmdline_start) - 1) != 0)
+ continue;
+ found = 1;
+ break;
+ }
+ if (!found)
+ goto no_start;
+ found = 0;
+
+ active = s - 1;
+ tmp = s = s + sizeof(cmdline_start) - 1;
+ e = p + sb.st_size - sizeof(cmdline_end);
+ while (tmp < e) {
+ if (memcmp(++tmp, cmdline_end, sizeof(cmdline_end)) != 0)
+ continue;
+ found = 1;
+ break;
+ }
+ if (!found)
+ goto no_end;
+
+ if (activate || clear || set) {
+ if (activate)
+ *active = activate > 0 ? '1' : '0';
+ if (clear)
+ memset(s, 0x0, tmp - s);
+ if (set)
+ snprintf(s, tmp - s, "%s", string);
+ } else {
+ fprintf(stdout, "cmd_line size:%d\n", tmp - s);
+ fprintf(stdout, "cmd_line: %s\n", s);
+ fprintf(stdout, "active: %c\n", *active);
+ }
+
+ munmap(p, sb.st_size);
+ close(fd);
+ return 0;
+
+ error:
+ perror(filename);
+ return 1;
+ no_start:
+ fprintf(stderr, "%s: %s not found.\n", filename, cmdline_start);
+ return 1;
+ no_end:
+ fprintf(stderr, "%s: %s not found.\n", filename, cmdline_end);
+ return 1;
+}
|
