X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Finput%2Fvcd.c;h=26cce118e2f17240ac7a89dbd369c032dea3fa76;hb=cdb134eb19e23528ec9c9dd89805087ea3edb9b6;hp=1f20033095e30066e46a9716a78f6f7a3c17e61c;hpb=d9251a2c9f1ca4380c27240ccca90c9f9ed46d3f;p=libsigrok.git

diff --git a/src/input/vcd.c b/src/input/vcd.c
index 1f200330..26cce118 100644
--- a/src/input/vcd.c
+++ b/src/input/vcd.c
@@ -26,7 +26,7 @@
  *
  * skip:        Allows skipping until given timestamp in the file.
  *              This can speed up analyzing of long captures.
- *            
+ *
  *              Value < 0: Skip until first timestamp listed in
  *              the file. (default)
  *
@@ -67,11 +67,12 @@
 
 #define LOG_PREFIX "input/vcd"
 
-#define CHUNKSIZE (1024 * 1024)
+#define CHUNK_SIZE (4 * 1024 * 1024)
 
 struct context {
 	gboolean started;
 	gboolean got_header;
+	uint64_t prev_timestamp;
 	uint64_t samplerate;
 	unsigned int maxchannels;
 	unsigned int channelcount;
@@ -318,7 +319,7 @@ static void add_samples(const struct sr_input *in, size_t count)
 	uint8_t *p;
 
 	inc = in->priv;
-	samples_per_chunk = CHUNKSIZE / inc->bytes_per_sample;
+	samples_per_chunk = CHUNK_SIZE / inc->bytes_per_sample;
 
 	while (count) {
 		space_left = samples_per_chunk - inc->samples_in_buffer;
@@ -367,12 +368,11 @@ static void process_bit(struct context *inc, char *identifier, unsigned int bit)
 static void parse_contents(const struct sr_input *in, char *data)
 {
 	struct context *inc;
-	uint64_t timestamp, prev_timestamp;
+	uint64_t timestamp;
 	unsigned int bit, i;
 	char **tokens;
 
 	inc = in->priv;
-	prev_timestamp = 0;
 
 	/* Read one space-delimited token at a time. */
 	tokens = g_strsplit_set(data, " \t\r\n", 0);
@@ -399,22 +399,22 @@ static void parse_contents(const struct sr_input *in, char *data)
 			 */
 			if (inc->skip < 0) {
 				inc->skip = timestamp;
-				prev_timestamp = timestamp;
+				inc->prev_timestamp = timestamp;
 			} else if (inc->skip > 0 && timestamp < (uint64_t)inc->skip) {
-				prev_timestamp = inc->skip;
-			} else if (timestamp == prev_timestamp) {
+				inc->prev_timestamp = inc->skip;
+			} else if (timestamp == inc->prev_timestamp) {
 				/* Ignore repeated timestamps (e.g. sigrok outputs these) */
 			} else {
-				if (inc->compress != 0 && timestamp - prev_timestamp > inc->compress) {
+				if (inc->compress != 0 && timestamp - inc->prev_timestamp > inc->compress) {
 					/* Compress long idle periods */
-					prev_timestamp = timestamp - inc->compress;
+					inc->prev_timestamp = timestamp - inc->compress;
 				}
 
 				sr_dbg("New timestamp: %" PRIu64, timestamp);
 
 				/* Generate samples from prev_timestamp up to timestamp - 1. */
-				add_samples(in, timestamp - prev_timestamp);
-				prev_timestamp = timestamp;
+				add_samples(in, timestamp - inc->prev_timestamp);
+				inc->prev_timestamp = timestamp;
 			}
 		} else if (tokens[i][0] == '$' && tokens[i][1] != '\0') {
 			/*
@@ -498,7 +498,7 @@ static int init(struct sr_input *in, GHashTable *options)
 	in->sdi = g_malloc0(sizeof(struct sr_dev_inst));
 	in->priv = inc;
 
-	inc->buffer = g_malloc(CHUNKSIZE);
+	inc->buffer = g_malloc(CHUNK_SIZE);
 
 	return SR_OK;
 }
@@ -625,10 +625,11 @@ static int reset(struct sr_input *in)
 }
 
 static struct sr_option options[] = {
-	{ "numchannels", "Number of channels", "Number of channels", NULL, NULL },
-	{ "skip", "Skip", "Skip until timestamp", NULL, NULL },
-	{ "downsample", "Downsample", "Divide samplerate by factor", NULL, NULL },
-	{ "compress", "Compress", "Compress idle periods longer than this value", NULL, NULL },
+	{ "numchannels", "Number of logic channels", "The number of (logic) channels in the data", NULL, NULL },
+	{ "skip", "Skip samples until timestamp", "Skip samples until the specified timestamp; "
+		"< 0: Skip until first timestamp listed; 0: Don't skip", NULL, NULL },
+	{ "downsample", "Downsampling factor", "Downsample, i.e. divide the samplerate by the specified factor", NULL, NULL },
+	{ "compress", "Compress idle periods", "Compress idle periods longer than the specified value", NULL, NULL },
 	ALL_ZERO
 };
 
@@ -647,7 +648,7 @@ static const struct sr_option *get_options(void)
 SR_PRIV struct sr_input_module input_vcd = {
 	.id = "vcd",
 	.name = "VCD",
-	.desc = "Value Change Dump",
+	.desc = "Value Change Dump data",
 	.exts = (const char*[]){"vcd", NULL},
 	.metadata = { SR_INPUT_META_HEADER | SR_INPUT_META_REQUIRED },
 	.options = get_options,