/*
 * This utility converts old-fashioned (non-AMR) TCS211 voice memo files
 * read out of FFS into hex strings that can be analyzed by a human,
 * either directly or with the aid of gsmfr-dlcap-parse utility from
 * Themyscira Wireless GSM codec libraries & utilities package.
 */

#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>

char *infname;
FILE *inf, *outf;

static unsigned
get_word()
{
	u_char b[2];
	int i, c;

	for (i = 0; i < 2; i++) {
		c = getc(inf);
		if (c < 0) {
			fprintf(stderr, "error: premature EOF in %s\n",
				infname);
			exit(1);
		}
		b[i] = c;
	}
	return((b[1] << 8) | b[0]);
}

convert_speech_sample()
{
	u_char bytes[34];
	int i, dp;
	unsigned word;

	dp = 0;
	for (i = 0; i < 17; i++) {
		word = get_word();
		bytes[dp++] = word >> 8;
		bytes[dp++] = word;
	}
	for (i = 0; i < 33; i++)
		fprintf(outf, "%02X", bytes[i]);
}

main(argc, argv)
	char **argv;
{
	unsigned first_word;

	if (argc < 2 || argc > 3) {
		fprintf(stderr, "usage: %s infile [outfile]\n", argv[0]);
		exit(1);
	}
	infname = argv[1];
	inf = fopen(infname, "r");
	if (!inf) {
		perror(infname);
		exit(1);
	}
	if (argc > 2) {
		outf = fopen(argv[2], "w");
		if (!outf) {
			perror(argv[2]);
			exit(1);
		}
	} else
		outf = stdout;

	for (;;) {
		first_word = get_word();
		if (first_word == 0xFBFF)	/* SC_VM_END_MASK */
			break;
		fprintf(outf, "%04X", first_word);
		if (first_word & 0x8000) {	/* B_VM_SPEECH */
			fprintf(outf, " %04X", get_word());
			fprintf(outf, " %04X", get_word());
			putc(' ', outf);
			convert_speech_sample();
		}
		putc('\n', outf);
	}
	exit(0);
}