[PATCH] Add a utility, unbootimg (v3)

[Bob Ham]

This program is the complement to mkbootimg.  It prints header
information and extracts kernel, ramdisk and 2nd boot images.

The second version was absent trailing whitespace, as per comments
from GNUtoo.  This third version includes two changes: correcting
the file name at the top of unbootimg.c and also changing the text
"image size" to "total image size" in the header printing.  It
also includes the S-o-b line below, also as per comments from
GNUtoo.

Signed-off-by: Bob Ham <rah at bash.sh>
---
 android/image-utils/mkbootimg/Makefile.am |    4 +-
 android/image-utils/mkbootimg/unbootimg.c |  196 +++++++++++++++++++++++++++++
 2 files changed, 199 insertions(+), 1 deletions(-)
 create mode 100644 android/image-utils/mkbootimg/unbootimg.c

diff --git a/android/image-utils/mkbootimg/Makefile.am b/android/image-utils/mkbootimg/Makefile.am
index 04be12e..77676fd 100644
--- a/android/image-utils/mkbootimg/Makefile.am
+++ b/android/image-utils/mkbootimg/Makefile.am
@@ -8,7 +8,7 @@ AM_CPPFLAGS = \
 -I$(top_builddir)/include \
 -I$(top_builddir)/mkbootimg
 
-bin_PROGRAMS = mkbootimg
+bin_PROGRAMS = mkbootimg unbootimg
 
 include_HEADERS = bootimg.h
 
@@ -18,3 +18,5 @@ mkbootimg.c
 mkbootimg_LDADD = $(top_builddir)/libmincrypt/libmincrypt.la
 mkbootimg_LDFLAGS =
 
+unbootimg_SOURCES = \
+unbootimg.c
diff --git a/android/image-utils/mkbootimg/unbootimg.c b/android/image-utils/mkbootimg/unbootimg.c
new file mode 100644
index 0000000..d3b4ffe
--- /dev/null
+++ b/android/image-utils/mkbootimg/unbootimg.c
@@ -0,0 +1,196 @@
+/* tools/mkbootimg/unbootimg.c
+**
+** Copyright 2007, The Android Open Source Project
+** Copyright 2011, Robert Ham <rah at bash.sh>
+**
+** Licensed under the Apache License, Version 2.0 (the "License");
+** you may not use this file except in compliance with the License.
+** You may obtain a copy of the License at
+**
+**     http://www.apache.org/licenses/LICENSE-2.0
+**
+** Unless required by applicable law or agreed to in writing, software
+** distributed under the License is distributed on an "AS IS" BASIS,
+** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+** See the License for the specific language governing permissions and
+** limitations under the License.
+**
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+#include "bootimg.h"
+
+static void *load_file(const char *fn, unsigned *_sz)
+{
+    char *data;
+    int sz;
+    int fd;
+
+    data = 0;
+    fd = open(fn, O_RDONLY);
+    if(fd < 0) return 0;
+
+    sz = lseek(fd, 0, SEEK_END);
+    if(sz < 0) goto oops;
+
+    if(lseek(fd, 0, SEEK_SET) != 0) goto oops;
+
+    data = (char*) malloc(sz);
+    if(data == 0) goto oops;
+
+    if(read(fd, data, sz) != sz) goto oops;
+    close(fd);
+
+    if(_sz) *_sz = sz;
+    return data;
+
+oops:
+    close(fd);
+    if(data != 0) free(data);
+    return 0;
+}
+
+static int write_file(const char *fn, void *data, unsigned sz)
+{
+    int fd, ret = 0;
+
+    fd = open(fn, O_WRONLY|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
+    if(fd < 0) {
+        fprintf(stderr, "error: could not open file `%s' for writing: %s\n", fn, strerror(errno));
+	return -1;
+    }
+
+    if(write(fd, data, sz) != sz) {
+        fprintf(stderr, "error: could not write to file `%s': %s\n", fn, strerror(errno));
+	unlink(fn);
+	ret = -1;
+    }
+
+    close(fd);
+    return ret;
+}
+
+static int write_image(const char *img, char **page_ptr, const char *fn, unsigned sz, unsigned page_size)
+{
+    if (fn) {
+        if(sz == 0)
+	    fprintf(stderr,"warning: no %s in boot image\n", img);
+	else
+	    if (write_file(fn, (*page_ptr), sz)) return -1;
+    }
+
+    *page_ptr += ((sz + page_size - 1) / page_size) * page_size;
+
+    return 0;
+}
+
+int usage(void)
+{
+    fprintf(stderr,"usage: unbootimg\n"
+            "       [ --kernel <filename> ]\n"
+            "       [ --ramdisk <filename> ]\n"
+            "       [ --second <2ndbootloader-filename> ]\n"
+            "       -i|--input <filename>\n"
+            );
+    return 1;
+}
+
+
+int main(int argc, char **argv)
+{
+    boot_img_hdr hdr;
+
+    char *kernel_fn = 0;
+    void *kernel_data = 0;
+    char *ramdisk_fn = 0;
+    void *ramdisk_data = 0;
+    char *second_fn = 0;
+    void *second_data = 0;
+    char *cmdline = 0;
+    char *bootimg = 0;
+    char *board = 0;
+    int fd;
+    char *data;
+    unsigned sz;
+    char *page_ptr;
+    unsigned i;
+
+    argc--;
+    argv++;
+
+    while(argc > 0){
+        char *arg = argv[0];
+        char *val = argv[1];
+        if(argc < 2) {
+            return usage();
+        }
+        argc -= 2;
+        argv += 2;
+        if(!strcmp(arg, "--input") || !strcmp(arg, "-i")) {
+            bootimg = val;
+        } else if(!strcmp(arg, "--kernel")) {
+            kernel_fn = val;
+        } else if(!strcmp(arg, "--ramdisk")) {
+            ramdisk_fn = val;
+        } else if(!strcmp(arg, "--second")) {
+            second_fn = val;
+        } else {
+            return usage();
+        }
+    }
+
+    if(bootimg == 0) {
+        fprintf(stderr,"error: no input filename specified\n");
+        return usage();
+    }
+
+
+    data = load_file(bootimg, &sz);
+    if (!data) {
+        fprintf(stderr,"error loading boot image: $s\n", strerror(errno));
+	return 1;
+    }
+
+    if (memcmp(data, BOOT_MAGIC, BOOT_MAGIC_SIZE) != 0) {
+        fprintf(stderr,"error: supplied file is not an Android boot image\n");
+        return 1;
+    }
+
+    memcpy(&hdr, data, sizeof(hdr));
+
+    printf("total image size:   %u\n"
+	   "kernel size:        %u\n"
+	   "kernel load addr:   0x%x\n"
+	   "ramdisk size:       %u\n"
+	   "ramdisk load addr:  0x%x\n"
+	   "2nd boot size:      %u\n"
+	   "2nd boot load addr: 0x%x\n"
+	   "kernel tags addr:   0x%x\n"
+	   "page size:          %u\n"
+	   "board:              `%s'\n"
+	   "cmdline:            `%s'\n"
+	   "id:                 ",
+	   sz,
+	   hdr.kernel_size, hdr.kernel_addr,
+	   hdr.ramdisk_size, hdr.ramdisk_addr,
+	   hdr.second_size, hdr.second_addr,
+	   hdr.tags_addr, hdr.page_size, hdr.name, hdr.cmdline);
+    for (i = 0; i < 8; ++i) printf("%x", hdr.id[i]);
+    printf("\n");
+
+    page_ptr = data + hdr.page_size;
+
+    if (write_image("kernel",   &page_ptr, kernel_fn,  hdr.kernel_size,  hdr.page_size)) return 1;
+    if (write_image("ramdisk",  &page_ptr, ramdisk_fn, hdr.ramdisk_size, hdr.page_size)) return 1;
+    if (write_image("2nd boot", &page_ptr, second_fn,  hdr.second_size,  hdr.page_size)) return 1;
+
+    free(data);
+    return 0;
+}
-- 
1.7.2.5