/*
 * This program reads a 16-bit PCM recording in raw format (robe by default,
 * or LE with -l option) and checks whether or not every sample fits into
 * left-justified 13 bits, with the 3 least significant bits of every 16-bit
 * sample cleared.
 */

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>

main(argc, argv)
	char **argv;
{
	int little_endian;
	char *infname;
	FILE *inf;
	unsigned sample_count;
	uint8_t inb[2];
	uint16_t ins, lowbits;
	int cc;

	if (argc == 2 && argv[1][0] != '-') {
		little_endian = 0;
		infname = argv[1];
	} else if (argc == 3 && !strcmp(argv[1], "-l")) {
		little_endian = 1;
		infname = argv[2];
	} else {
		fprintf(stderr, "usage: %s [-l] input.pcm16\n", argv[0]);
		exit(1);
	}
	inf = fopen(infname, "r");
	if (!inf) {
		perror(infname);
		exit(1);
	}
	for (sample_count = 0; ; sample_count++) {
		cc = fread(inb, 1, 2, inf);
		if (cc <= 0)
			break;
		if (cc & 1) {
			fprintf(stderr, "error: %s has odd number of bytes\n",
				infname);
			exit(1);
		}
		if (little_endian)
			ins = ((uint16_t) inb[1] << 8) | ((uint16_t) inb[0]);
		else
			ins = ((uint16_t) inb[0] << 8) | ((uint16_t) inb[1]);
		lowbits = ins & 7;
		if (lowbits) {
			fprintf(stderr,
			"check13 fail: %s sample #%u low 3 bits are %u\n",
				infname, sample_count, lowbits);
			exit(1);
		}
	}
	exit(0);
}