Initial Contribution
diff --git a/mtdutils/flash_image.c b/mtdutils/flash_image.c
new file mode 100644
index 0000000..c776876
--- /dev/null
+++ b/mtdutils/flash_image.c
@@ -0,0 +1,140 @@
+/*
+ * 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"
+
+#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);
+ LOGE("%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 = read(fd, header, sizeof(header));
+ if (headerlen <= 0) die("error reading %s header", argv[2]);
+
+ MtdReadContext *in = mtd_read_partition(partition);
+ if (in == NULL) {
+ LOGW("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) {
+ LOGW("error reading %s: %s\n", argv[1], strerror(errno));
+ // just assume it needs re-writing
+ } else if (checklen == headerlen && !memcmp(header, check, headerlen)) {
+ LOGI("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
+ LOGI("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 = 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 (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 = 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;
+}