vcd: Output timestamp only once per change.

[libsigrok.git] / output / vcd.c

diff --git a/output/vcd.c b/output/vcd.c
index d89284927602a55d7a3e87beb5753b0d02e0cf07..49d2d195a409e5da702de6d2b00729ff9a1c4348 100644 (file)
--- a/output/vcd.c
+++ b/output/vcd.c
@@ -26,14 +26,7 @@
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
-/* Message logging helpers with driver-specific prefix string. */
-#define DRIVER_LOG_DOMAIN "output/vcd: "
-#define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args)
-#define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args)
+#define LOG_PREFIX "output/vcd"
 
 struct context {
        int num_enabled_probes;
@@ -42,6 +35,7 @@ struct context {
        uint8_t *prevsample;
        int period;
        uint64_t samplerate;
+       uint64_t samplecount;
        unsigned int unitsize;
 };
 
@@ -69,6 +63,8 @@ static int init(struct sr_output *o)
 
        for (l = o->sdi->probes; l; l = l->next) {
                probe = l->data;
+               if (probe->type != SR_PROBE_LOGIC)
+                       continue;
                if (!probe->enabled)
                        continue;
                ctx->probeindices = g_array_append_val(
@@ -95,8 +91,8 @@ static int init(struct sr_output *o)
        g_string_append_printf(ctx->header, "$version %s %s $end\n",
                        PACKAGE, PACKAGE_VERSION);
 
-       if (sr_config_get(o->sdi->driver, SR_CONF_SAMPLERATE, &gvar,
-                       o->sdi) == SR_OK) {
+       if (sr_config_get(o->sdi->driver, o->sdi, NULL, SR_CONF_SAMPLERATE,
+                       &gvar) == SR_OK) {
                ctx->samplerate = g_variant_get_uint64(gvar);
                g_variant_unref(gvar);
                if (!((samplerate_s = sr_samplerate_string(ctx->samplerate)))) {
@@ -131,6 +127,8 @@ static int init(struct sr_output *o)
        /* Wires / channels */
        for (i = 0, l = o->sdi->probes; l; l = l->next, i++) {
                probe = l->data;
+               if (probe->type != SR_PROBE_LOGIC)
+                       continue;
                if (!probe->enabled)
                        continue;
                g_string_append_printf(ctx->header, "$var wire 1 %c %s $end\n",
@@ -158,7 +156,7 @@ static int receive(struct sr_output *o, const struct sr_dev_inst *sdi,
        unsigned int i;
        int p, curbit, prevbit, index;
        uint8_t *sample;
-       static uint64_t samplecount = 0;
+       gboolean timestamp_written;
 
        (void)sdi;
 
@@ -177,31 +175,46 @@ static int receive(struct sr_output *o, const struct sr_dev_inst *sdi,
                /* The header is still here, this must be the first packet. */
                *out = ctx->header;
                ctx->header = NULL;
+               ctx->samplecount = 0;
        } else {
                *out = g_string_sized_new(512);
        }
 
        logic = packet->payload;
        for (i = 0; i <= logic->length - logic->unitsize; i += logic->unitsize) {
-               samplecount++;
-
                sample = logic->data + i;
+               timestamp_written = FALSE;
 
                for (p = 0; p < ctx->num_enabled_probes; p++) {
                        index = g_array_index(ctx->probeindices, int, p);
-                       curbit = (sample[p / 8] & (((uint8_t) 1) << index)) >> index;
-                       prevbit = (ctx->prevsample[p / 8] & (((uint64_t) 1) << index)) >> index;
+
+                       curbit = ((unsigned)sample[index / 8]
+                                       >> (index % 8)) & 1;
+                       prevbit = ((unsigned)ctx->prevsample[index / 8]
+                                       >> (index % 8)) & 1;
 
                        /* VCD only contains deltas/changes of signals. */
-                       if (prevbit == curbit)
+                       if (prevbit == curbit && ctx->samplecount > 0)
                                continue;
 
+                       /* Output timestamp of subsequent signal changes. */
+                       if (!timestamp_written)
+                               g_string_append_printf(*out, "#%.0f",
+                                       (double)ctx->samplecount /
+                                               ctx->samplerate * ctx->period);
+
                        /* Output which signal changed to which value. */
-                       g_string_append_printf(*out, "#%" PRIu64 "\n%i%c\n",
-                                       (uint64_t)(((float)samplecount / ctx->samplerate)
-                                       * ctx->period), curbit, (char)('!' + p));
+                       g_string_append_c(*out, ' ');
+                       g_string_append_c(*out, '0' + curbit);
+                       g_string_append_c(*out, '!' + p);
+
+                       timestamp_written = TRUE;
                }
 
+               if (timestamp_written)
+                       g_string_append_c(*out, '\n');
+
+               ctx->samplecount++;
                memcpy(ctx->prevsample, sample, ctx->unitsize);
        }