input/vcd: Add option to manually specify & enforce a samplerate

diff --git a/src/input/vcd.c b/src/input/vcd.c
index d5471a47163236f239fb7bef16d5fc9abcdf620b..816e5096a3d04341771395cf92fbb7175f334d4c 100644 (file)
--- a/src/input/vcd.c
+++ b/src/input/vcd.c
@@ -35,6 +35,9 @@
  *     timestamp 0.
  *   Value > 0: Start at the given timestamp.
  *
+ * samplerate: overwrite/manually specify the samplerate for this VCD file
+ *   and ignore timescale sections.
+ *
  * downsample: Divide the samplerate by the given factor. This can
  *   speed up operation on long captures.
  *
@@ -123,6 +126,7 @@
 struct context {
        struct vcd_user_opt {
                size_t maxchannels; /* sigrok channels (output) */
+               uint64_t samplerate;
                uint64_t downsample;
                uint64_t compress;
                uint64_t skip_starttime;
@@ -557,6 +561,11 @@ static int parse_timescale(struct context *inc, char *contents)
 {
        uint64_t p, q;
 
+       if (inc->options.samplerate != 0) {
+               sr_info("Ignoring timescale section as the samplerate was manually overwritten!");
+               return SR_OK;
+       }
+
        /*
         * The standard allows for values 1, 10 or 100
         * and units s, ms, us, ns, ps and fs.
@@ -1945,6 +1954,13 @@ static int init(struct sr_input *in, GHashTable *options)
        data = g_hash_table_lookup(options, "numchannels");
        inc->options.maxchannels = g_variant_get_uint32(data);
 
+       data = g_hash_table_lookup(options, "samplerate_overwrite");
+       inc->options.samplerate = g_variant_get_uint64(data);
+       if (inc->options.samplerate != 0) {
+               // Set the samplerate
+               inc->samplerate = inc->options.samplerate;
+       }
+
        data = g_hash_table_lookup(options, "downsample");
        inc->options.downsample = g_variant_get_uint64(data);
        if (inc->options.downsample < 1)
@@ -2083,6 +2099,7 @@ static int reset(struct sr_input *in)
 
 enum vcd_option_t {
        OPT_NUM_CHANS,
+       OPT_SAMPLERATE,
        OPT_DOWN_SAMPLE,
        OPT_SKIP_COUNT,
        OPT_COMPRESS,
@@ -2095,6 +2112,13 @@ static struct sr_option options[] = {
                "The maximum number of sigrok channels to create for VCD input signals.",
                NULL, NULL,
        },
+       [OPT_SAMPLERATE] = {
+               "samplerate_overwrite", "Overwrite Samplerate",
+               "Overwrite the input file's samplerate, i.e. for frequencies not representable via timescale."
+               "By default the VCD file is searched for a timescale section to compute the samplerate."
+               "For values other than 0 this value will be considered as the actual samplerate and the timescale section will be ignored.",
+               NULL, NULL,
+       },
        [OPT_DOWN_SAMPLE] = {
                "downsample", "Downsampling factor",
                "Downsample the input file's samplerate, i.e. divide by the specified factor.",
@@ -2120,6 +2144,7 @@ static const struct sr_option *get_options(void)
 {
        if (!options[0].def) {
                options[OPT_NUM_CHANS].def = g_variant_ref_sink(g_variant_new_uint32(0));
+               options[OPT_SAMPLERATE].def = g_variant_ref_sink(g_variant_new_uint64(0));
                options[OPT_DOWN_SAMPLE].def = g_variant_ref_sink(g_variant_new_uint64(1));
                options[OPT_SKIP_COUNT].def = g_variant_ref_sink(g_variant_new_uint64(~UINT64_C(0)));
                options[OPT_COMPRESS].def = g_variant_ref_sink(g_variant_new_uint64(0));