gnuplot output: Optimize by only storing changes.

[libsigrok.git] / output / output_gnuplot.c

diff --git a/output/output_gnuplot.c b/output/output_gnuplot.c
index ec50b9d2bfa8a6c3bc794986f5bb98351eb9134d..dfa91eb78b39f8a8db1638cba7409bf497684572 100644 (file)
--- a/output/output_gnuplot.c
+++ b/output/output_gnuplot.c
@@ -22,6 +22,7 @@
 #include <string.h>
 #include <glib.h>
 #include <sigrok.h>
+#include <sigrok-internal.h>
 #include "config.h"
 
 struct context {
@@ -61,29 +62,29 @@ static int init(struct sr_output *o)
        time_t t;
 
        if (!o) {
-               g_warning("gnuplot out: %s: o was NULL", __func__);
+               sr_warn("gnuplot out: %s: o was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!o->device) {
-               g_warning("gnuplot out: %s: o->device was NULL", __func__);
+               sr_warn("gnuplot out: %s: o->device was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!o->device->plugin) {
-               g_warning("gnuplot out: %s: o->device->plugin was NULL",
-                         __func__);
+               sr_warn("gnuplot out: %s: o->device->plugin was NULL",
+                       __func__);
                return SR_ERR_ARG;
        }
 
        if (!(ctx = calloc(1, sizeof(struct context)))) {
-               g_warning("gnuplot out: %s: ctx calloc failed", __func__);
+               sr_warn("gnuplot out: %s: ctx calloc failed", __func__);
                return SR_ERR_MALLOC;
        }
 
        if (!(ctx->header = calloc(1, MAX_HEADER_LEN + 1))) {
-               g_warning("gnuplot out: %s: ctx->header calloc failed",
-                         __func__);
+               sr_warn("gnuplot out: %s: ctx->header calloc failed",
+                       __func__);
                free(ctx);
                return SR_ERR_MALLOC;
        }
@@ -105,8 +106,8 @@ static int init(struct sr_output *o)
                samplerate = *((uint64_t *) o->device->plugin->get_device_info(
                                o->device->plugin_index, SR_DI_CUR_SAMPLERATE));
                if (!(frequency_s = sr_samplerate_string(samplerate))) {
-                       g_warning("gnuplot out: %s: sr_samplerate_string "
-                                 "failed", __func__);
+                       sr_warn("gnuplot out: %s: sr_samplerate_string failed",
+                               __func__);
                        free(ctx->header);
                        free(ctx);
                        return SR_ERR;
@@ -124,7 +125,7 @@ static int init(struct sr_output *o)
        }
 
        if (!(frequency_s = sr_period_string(samplerate))) {
-               g_warning("gnuplot out: %s: sr_period_string failed", __func__);
+               sr_warn("gnuplot out: %s: sr_period_string failed", __func__);
                free(ctx->header);
                free(ctx);
                return SR_ERR;
@@ -137,7 +138,7 @@ static int init(struct sr_output *o)
        free(frequency_s);
 
        if (b < 0) {
-               g_warning("gnuplot out: %s: sprintf failed", __func__);
+               sr_warn("gnuplot out: %s: sprintf failed", __func__);
                free(ctx->header);
                free(ctx);
                return SR_ERR;
@@ -152,17 +153,17 @@ static int event(struct sr_output *o, int event_type, char **data_out,
        struct context *ctx;
 
        if (!o) {
-               g_warning("gnuplot out: %s: o was NULL", __func__);
+               sr_warn("gnuplot out: %s: o was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!data_out) {
-               g_warning("gnuplot out: %s: data_out was NULL", __func__);
+               sr_warn("gnuplot out: %s: data_out was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!length_out) {
-               g_warning("gnuplot out: %s: length_out was NULL", __func__);
+               sr_warn("gnuplot out: %s: length_out was NULL", __func__);
                return SR_ERR_ARG;
        }
 
@@ -177,8 +178,8 @@ static int event(struct sr_output *o, int event_type, char **data_out,
                o->internal = NULL;
                break;
        default:
-               g_warning("gnuplot out: %s: unsupported event type: %d",
-                         __func__, event_type);
+               sr_warn("gnuplot out: %s: unsupported event type: %d",
+                       __func__, event_type);
                break;
        }
 
@@ -194,31 +195,31 @@ static int data(struct sr_output *o, const char *data_in, uint64_t length_in,
        struct context *ctx;
        unsigned int max_linelen, outsize, p, curbit, i;
        uint64_t sample;
-       static uint64_t samplecount = 0;
+       static uint64_t samplecount = 0, old_sample = 0;
        char *outbuf, *c;
 
        if (!o) {
-               g_warning("gnuplot out: %s: o was NULL", __func__);
+               sr_warn("gnuplot out: %s: o was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!o->internal) {
-               g_warning("gnuplot out: %s: o->internal was NULL", __func__);
+               sr_warn("gnuplot out: %s: o->internal was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!data_in) {
-               g_warning("gnuplot out: %s: data_in was NULL", __func__);
+               sr_warn("gnuplot out: %s: data_in was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!data_out) {
-               g_warning("gnuplot out: %s: data_out was NULL", __func__);
+               sr_warn("gnuplot out: %s: data_out was NULL", __func__);
                return SR_ERR_ARG;
        }
 
        if (!length_out) {
-               g_warning("gnuplot out: %s: length_out was NULL", __func__);
+               sr_warn("gnuplot out: %s: length_out was NULL", __func__);
                return SR_ERR_ARG;
        }
 
@@ -229,7 +230,7 @@ static int data(struct sr_output *o, const char *data_in, uint64_t length_in,
                outsize += strlen(ctx->header);
 
        if (!(outbuf = calloc(1, outsize))) {
-               g_warning("gnuplot out: %s: outbuf calloc failed", __func__);
+               sr_warn("gnuplot out: %s: outbuf calloc failed", __func__);
                return SR_ERR_MALLOC;
        }
 
@@ -242,8 +243,19 @@ static int data(struct sr_output *o, const char *data_in, uint64_t length_in,
        }
 
        for (i = 0; i <= length_in - ctx->unitsize; i += ctx->unitsize) {
+
                memcpy(&sample, data_in + i, ctx->unitsize);
 
+               /*
+                * Don't output the same samples multiple times. However, make
+                * sure to output at least the first and last sample.
+                */
+               if (samplecount++ != 0 && sample == old_sample) {
+                       if (i != (length_in - ctx->unitsize))
+                               continue;
+               }
+               old_sample = sample;
+
                /* The first column is a counter (needed for gnuplot). */
                c = outbuf + strlen(outbuf);
                sprintf(c, "%" PRIu64 "\t", samplecount++);