output/csv: complete and improve timestamp construction support

[libsigrok.git] / src / output / csv.c

diff --git a/src/output/csv.c b/src/output/csv.c
index 791ddc39b9267ae4841312430847a9f06f647a33..296d9a06b0ab541037b588b63a42f7d62b13a619 100644 (file)
--- a/src/output/csv.c
+++ b/src/output/csv.c
@@ -95,7 +95,7 @@ struct context {
        uint32_t channels_seen;
        uint64_t sample_rate;
        uint64_t sample_scale;
-       uint64_t sample_time;
+       uint64_t out_sample_count;
        uint8_t *previous_sample;
        float *analog_samples;
        uint8_t *logic_samples;
@@ -278,6 +278,10 @@ static GString *gen_header(const struct sr_output *o,
                ctx->did_header = TRUE;
        }
 
+       /* Time column requested but samplerate unknown. Emit a warning. */
+       if (ctx->time && !ctx->sample_rate)
+               sr_warn("Samplerate unknown, cannot provide timestamps.");
+
        return header;
 }
 
@@ -399,6 +403,8 @@ static void process_logic(struct context *ctx,
 static void dump_saved_values(struct context *ctx, GString **out)
 {
        unsigned int i, j, analog_size, num_channels;
+       double sample_time_dbl;
+       uint64_t sample_time_u64;
        float *analog_sample, value;
        uint8_t *logic_sample;
 
@@ -416,8 +422,8 @@ static void dump_saved_values(struct context *ctx, GString **out)
                if (ctx->label_do) {
                        if (ctx->time)
                                g_string_append_printf(*out, "%s%s",
-                                       ctx->label_names ? "Time" :
-                                       ctx->xlabel, ctx->value);
+                                       ctx->label_names ? "Time" : ctx->xlabel,
+                                       ctx->value);
                        for (i = 0; i < num_channels; i++) {
                                g_string_append_printf(*out, "%s%s",
                                        ctx->channels[i].label, ctx->value);
@@ -440,7 +446,6 @@ static void dump_saved_values(struct context *ctx, GString **out)
                        ctx->previous_sample = g_malloc0(analog_size + ctx->num_logic_channels);
 
                for (i = 0; i < ctx->num_samples; i++) {
-                       ctx->sample_time = (ctx->sample_scale * i) / ctx->sample_rate;
                        analog_sample =
                            &ctx->analog_samples[i * ctx->num_analog_channels];
                        logic_sample =
@@ -462,9 +467,16 @@ static void dump_saved_values(struct context *ctx, GString **out)
                                       analog_sample, analog_size);
                        }
 
-                       if (ctx->time)
+                       if (ctx->time && !ctx->sample_rate) {
+                               g_string_append_printf(*out, "0%s", ctx->value);
+                       } else if (ctx->time) {
+                               sample_time_dbl = ctx->out_sample_count++;
+                               sample_time_dbl /= ctx->sample_rate;
+                               sample_time_dbl *= ctx->sample_scale;
+                               sample_time_u64 = sample_time_dbl;
                                g_string_append_printf(*out, "%" PRIu64 "%s",
-                                       ctx->sample_time, ctx->value);
+                                       sample_time_u64, ctx->value);
+                       }
 
                        for (j = 0; j < num_channels; j++) {
                                if (ctx->channels[j].ch->type == SR_CHANNEL_ANALOG) {