/*
 * split LOAD/Flash images from Siemens SE505
 *
 * (c) 01/2005 Olaf Rempel <razzor at kopf minus tisch dot de>
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include <sys/types.h>
#include "trxhdr.h"

#define BUFSIZE 32768

int main(int argc, char *argv[]) {
	struct trx_header trx;
	int i = 1, len, cnt;
	FILE *fp, *out;
	char *buf, filename[128];

	if (argc <= 1) {
		printf("USAGE: split_image firmware.img\n");
		exit(-1);
	}

	// open file
	if ((fp = fopen(argv[1], "r")) < 0) {
		perror(argv[1]);
		exit(-1);
	}

	// read main header
	if ((cnt = fread(&trx, 1, sizeof(struct trx_header), fp)) < 0) {
		perror(argv[1]);
		fclose(fp);
		exit(-1);

	} else if (cnt < sizeof(struct trx_header)) {
		fprintf(stderr, "Truncated file: %s\n", argv[1]);
		fclose(fp);
		exit(-1);

	} else if (trx.magic != FILE_MAGIC || trx.len > FILE_MAX_LEN || trx.len < sizeof(struct trx_header)) {
		fprintf(stderr, "Bad LOAD Header: %s\n", argv[1]);
		fclose(fp);
		exit(-1);
	}

	len = trx.len - sizeof(struct trx_header);

	if ((buf = malloc(BUFSIZE)) == NULL) {
		perror("malloc");
		exit(-1);
	}

	while (len > 0) {
		// read header
		if ((cnt = fread(&trx, 1, sizeof(struct trx_header), fp)) < 0) {
			perror(argv[1]);
			free(buf);
			fclose(fp);
			exit(-1);

		} else if (cnt < sizeof(struct trx_header)) {
			fprintf(stderr, "Truncated file: %s\n", argv[1]);
			free(buf);
			fclose(fp);
			exit(-1);

		} else if (trx.magic == TRX_MAGIC) {
			if (trx.len > TRX_MAX_LEN || trx.len < sizeof(struct trx_header)) {
				fprintf(stderr, "Bad TRX Header: %s\n", argv[1]);
				free(buf);
				fclose(fp);
				exit(-1);
			}

		} else if (trx.magic == PMON_MAGIC) {
			if (trx.len > PMON_MAX_LEN || trx.len < sizeof(struct trx_header)) {
				fprintf(stderr, "Bad PMON Header: %s\n", argv[1]);
				free(buf);
				fclose(fp);
				exit(-1);
			}

		} else if (trx.magic == NVAR_MAGIC) {
			if (trx.len > NVRAM_MAX_LEN || trx.len < sizeof(struct trx_header)) {
				fprintf(stderr, "Bad NVRAM Header: %s\n", argv[1]);
				free(buf);
				fclose(fp);
				exit(-1);
			}

		} else {
			fprintf(stderr, "Unknown Header Type: %s\n", argv[1]);
			free(buf);
			fclose(fp);
			exit(-1);
		}

		// bad bad (unknown length)
		snprintf(filename, sizeof(filename), "%s.%d.trx", argv[1], i++);

		// open file
		if ((out = fopen(filename, "w")) < 0) {
			perror(filename);
			free(buf);
			exit(-1);
		}

		printf("%s : %d bytes\n", filename, trx.len);
		fwrite(&trx, 1, sizeof(struct trx_header), out);

		len -= trx.len;
		trx.len -= sizeof(struct trx_header);

		while (trx.len > 0 && cnt > 0) {
			cnt = fread(buf, 1, (trx.len <= BUFSIZE ? trx.len : BUFSIZE), fp);
			fwrite(buf, 1, cnt, out);
			trx.len -= cnt;
		}

		fclose(out);
	}

	free(buf);

	fclose(fp);

	return 0;
}