/* * 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 * * 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 <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 #endif #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); va_end(args); if (err != 0) { strlcat(buf, ": ", sizeof(buf)); strlcat(buf, strerror(err), sizeof(buf)); } fprintf(stderr, "%s\n", buf); ALOGE("%s\n", buf); exit(1); } /* 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; } mtd_read_close(in); } // 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; }