From 04864faac5c0bfc38a0e7cfd204cb4607ef62b63 Mon Sep 17 00:00:00 2001
From: Harald Welte <laforge@gnumonks.org>
Date: Tue, 6 Mar 2012 13:05:46 +0100
Subject: [PATCH] add check_ctr.c

---
 utils/check_ctr.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 utils/check_ctr.c

diff --git a/utils/check_ctr.c b/utils/check_ctr.c
new file mode 100644
index 0000000..3c0909e
--- /dev/null
+++ b/utils/check_ctr.c
@@ -0,0 +1,86 @@
+/* utility to check a recorded WAV file in fgpa.test_mode=1 for
+ * discontinuities in the counter increment/decrements */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#define STEP 1
+
+static int check_continuity(uint16_t *samples, uint32_t size)
+{
+	uint16_t *end = samples + size/sizeof(uint16_t);
+	uint16_t *cur;
+	int inited = 0;
+	uint16_t last_i, last_q;
+
+	for (cur = samples; cur < end; cur += 2) {
+		if (!inited) {
+			last_i = cur[0];
+			last_q = cur[1];
+			printf("initial I=%04x, Q=%04x\n",
+				last_i, last_q);
+			inited = 1;
+			continue;
+		}
+
+		if (cur[0] != (uint16_t)(last_i - STEP) ||
+		    cur[1] != (uint16_t)(last_q + STEP)) {
+			fprintf(stderr, "Disocntinuity at %u: "
+				"I=%04x/%04x Q=%04x/%04x\n",
+				cur - samples, last_i, cur[0],
+				last_q, cur[1]);
+		}
+
+		last_i = cur[0];
+		last_q = cur[1];
+	}
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	struct stat st;
+	int fd;
+	void *map;
+	uint16_t *samples;
+
+	if (argc < 2) {
+		fprintf(stderr, "You have to specify a wave file name\n");
+		exit(2);
+	}
+
+	fd = open(argv[1], O_RDONLY);
+	if (fd < 0) {
+		perror("opening file");
+		exit(2);
+	}
+
+	if (fstat(fd, &st) < 0) {
+		perror("stat");
+		exit(1);
+	}
+
+	map = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
+	if (!map) {
+		perror("mmap");
+		exit(1);
+	}
+
+	if (memcmp(map, "RIFF", 4)) {
+		fprintf(stderr, "Doeesn't look like a WAV file\n");
+		exit(1);
+	}
+
+	samples = (uint16_t *)(map + 0x44);
+	check_continuity(samples, st.st_size-0x44);
+
+	exit(0);
+}