blob: 36ffa131459659f2cb8f91ac587592e49abb7a0a [file] [log] [blame]
* Copyright (C) 2008 The Android Open Source Project
* 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
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "cutils/log.h"
#include "mtdutils.h"
#ifdef LOG_TAG
#undef LOG_TAG
#define LOG_TAG "flash_image"
#define HEADER_SIZE 2048 // size of header to compare for equality
void die(const char *msg, ...) {
int err = errno;
va_list args;
va_start(args, msg);
char buf[1024];
vsnprintf(buf, sizeof(buf), msg, args);
if (err != 0) {
strlcat(buf, ": ", sizeof(buf));
strlcat(buf, strerror(err), sizeof(buf));
fprintf(stderr, "%s\n", buf);
ALOGE("%s\n", buf);
/* Read an image file and write it to a flash partition. */
int main(int argc, char **argv) {
const MtdPartition *ptn;
MtdWriteContext *write;
void *data;
unsigned sz;
if (argc != 3) {
fprintf(stderr, "usage: %s partition file.img\n", argv[0]);
return 2;
if (mtd_scan_partitions() <= 0) die("error scanning partitions");
const MtdPartition *partition = mtd_find_partition_by_name(argv[1]);
if (partition == NULL) die("can't find %s partition", argv[1]);
// If the first part of the file matches the partition, skip writing
int fd = open(argv[2], O_RDONLY);
if (fd < 0) die("error opening %s", argv[2]);
char header[HEADER_SIZE];
int headerlen = TEMP_FAILURE_RETRY(read(fd, header, sizeof(header)));
if (headerlen <= 0) die("error reading %s header", argv[2]);
MtdReadContext *in = mtd_read_partition(partition);
if (in == NULL) {
ALOGW("error opening %s: %s\n", argv[1], strerror(errno));
// just assume it needs re-writing
} else {
char check[HEADER_SIZE];
int checklen = mtd_read_data(in, check, sizeof(check));
if (checklen <= 0) {
ALOGW("error reading %s: %s\n", argv[1], strerror(errno));
// just assume it needs re-writing
} else if (checklen == headerlen && !memcmp(header, check, headerlen)) {
ALOGI("header is the same, not flashing %s\n", argv[1]);
return 0;
// Skip the header (we'll come back to it), write everything else
ALOGI("flashing %s from %s\n", argv[1], argv[2]);
MtdWriteContext *out = mtd_write_partition(partition);
if (out == NULL) die("error writing %s", argv[1]);
char buf[HEADER_SIZE];
memset(buf, 0, headerlen);
int wrote = mtd_write_data(out, buf, headerlen);
if (wrote != headerlen) die("error writing %s", argv[1]);
int len;
while ((len = TEMP_FAILURE_RETRY(read(fd, buf, sizeof(buf)))) > 0) {
wrote = mtd_write_data(out, buf, len);
if (wrote != len) die("error writing %s", argv[1]);
if (len < 0) die("error reading %s", argv[2]);
if (mtd_write_close(out)) die("error closing %s", argv[1]);
// Now come back and write the header last
out = mtd_write_partition(partition);
if (out == NULL) die("error re-opening %s", argv[1]);
wrote = mtd_write_data(out, header, headerlen);
if (wrote != headerlen) die("error re-writing %s", argv[1]);
// Need to write a complete block, so write the rest of the first block
size_t block_size;
if (mtd_partition_info(partition, NULL, &block_size, NULL))
die("error getting %s block size", argv[1]);
if (TEMP_FAILURE_RETRY(lseek(fd, headerlen, SEEK_SET)) != headerlen)
die("error rewinding %s", argv[2]);
int left = block_size - headerlen;
while (left < 0) left += block_size;
while (left > 0) {
len = TEMP_FAILURE_RETRY(read(fd, buf, left > (int)sizeof(buf) ? (int)sizeof(buf) : left));
if (len <= 0) die("error reading %s", argv[2]);
if (mtd_write_data(out, buf, len) != len)
die("error writing %s", argv[1]);
left -= len;
if (mtd_write_close(out)) die("error closing %s", argv[1]);
return 0;