libsigrok/output/vcd.c

232 lines
6.2 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include "config.h" /* Needed for PACKAGE and others. */
#include "libsigrok.h"
#include "libsigrok-internal.h"
/* Message logging helpers with subsystem-specific prefix string. */
#define LOG_PREFIX "output/vcd: "
#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
struct context {
int num_enabled_probes;
GArray *probeindices;
GString *header;
uint8_t *prevsample;
int period;
uint64_t samplerate;
unsigned int unitsize;
};
static const char *vcd_header_comment = "\
$comment\n Acquisition with %d/%d probes at %s\n$end\n";
static int init(struct sr_output *o)
{
struct context *ctx;
struct sr_probe *probe;
GSList *l;
GVariant *gvar;
int num_probes, i;
char *samplerate_s, *frequency_s, *timestamp;
time_t t;
if (!(ctx = g_try_malloc0(sizeof(struct context)))) {
sr_err("%s: ctx malloc failed", __func__);
return SR_ERR_MALLOC;
}
o->internal = ctx;
ctx->num_enabled_probes = 0;
ctx->probeindices = g_array_new(FALSE, FALSE, sizeof(int));
for (l = o->sdi->probes; l; l = l->next) {
probe = l->data;
if (!probe->enabled)
continue;
ctx->probeindices = g_array_append_val(
ctx->probeindices, probe->index);
ctx->num_enabled_probes++;
}
if (ctx->num_enabled_probes > 94) {
sr_err("VCD only supports 94 probes.");
return SR_ERR;
}
ctx->unitsize = (ctx->num_enabled_probes + 7) / 8;
ctx->header = g_string_sized_new(512);
num_probes = g_slist_length(o->sdi->probes);
/* timestamp */
t = time(NULL);
timestamp = g_strdup(ctime(&t));
timestamp[strlen(timestamp)-1] = 0;
g_string_printf(ctx->header, "$date %s $end\n", timestamp);
g_free(timestamp);
/* generator */
g_string_append_printf(ctx->header, "$version %s %s $end\n",
PACKAGE, PACKAGE_VERSION);
if (sr_config_get(o->sdi->driver, SR_CONF_SAMPLERATE, &gvar,
o->sdi) == SR_OK) {
ctx->samplerate = g_variant_get_uint64(gvar);
g_variant_unref(gvar);
if (!((samplerate_s = sr_samplerate_string(ctx->samplerate)))) {
g_string_free(ctx->header, TRUE);
g_free(ctx);
return SR_ERR;
}
g_string_append_printf(ctx->header, vcd_header_comment,
ctx->num_enabled_probes, num_probes, samplerate_s);
g_free(samplerate_s);
}
/* timescale */
/* VCD can only handle 1/10/100 (s - fs), so scale up first */
if (ctx->samplerate > SR_MHZ(1))
ctx->period = SR_GHZ(1);
else if (ctx->samplerate > SR_KHZ(1))
ctx->period = SR_MHZ(1);
else
ctx->period = SR_KHZ(1);
if (!(frequency_s = sr_period_string(ctx->period))) {
g_string_free(ctx->header, TRUE);
g_free(ctx);
return SR_ERR;
}
g_string_append_printf(ctx->header, "$timescale %s $end\n", frequency_s);
g_free(frequency_s);
/* scope */
g_string_append_printf(ctx->header, "$scope module %s $end\n", PACKAGE);
/* Wires / channels */
for (i = 0, l = o->sdi->probes; l; l = l->next, i++) {
probe = l->data;
if (!probe->enabled)
continue;
g_string_append_printf(ctx->header, "$var wire 1 %c %s $end\n",
(char)('!' + i), probe->name);
}
g_string_append(ctx->header, "$upscope $end\n"
"$enddefinitions $end\n$dumpvars\n");
if (!(ctx->prevsample = g_try_malloc0(ctx->unitsize))) {
g_string_free(ctx->header, TRUE);
g_free(ctx);
sr_err("%s: ctx->prevsample malloc failed", __func__);
return SR_ERR_MALLOC;
}
return SR_OK;
}
static int receive(struct sr_output *o, const struct sr_dev_inst *sdi,
const struct sr_datafeed_packet *packet, GString **out)
{
const struct sr_datafeed_logic *logic;
struct context *ctx;
unsigned int i;
int p, curbit, prevbit, index;
uint8_t *sample;
static uint64_t samplecount = 0;
(void)sdi;
*out = NULL;
if (!o || !o->internal)
return SR_ERR_ARG;
ctx = o->internal;
if (packet->type == SR_DF_END) {
*out = g_string_new("$dumpoff\n$end\n");
return SR_OK;
} else if (packet->type != SR_DF_LOGIC)
return SR_OK;
if (ctx->header) {
/* The header is still here, this must be the first packet. */
*out = ctx->header;
ctx->header = NULL;
} 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;
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;
/* VCD only contains deltas/changes of signals. */
if (prevbit == curbit)
continue;
/* 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));
}
memcpy(ctx->prevsample, sample, ctx->unitsize);
}
return SR_OK;
}
static int cleanup(struct sr_output *o)
{
struct context *ctx;
if (!o || !o->internal)
return SR_ERR_ARG;
ctx = o->internal;
g_free(ctx);
return SR_OK;
}
struct sr_output_format output_vcd = {
.id = "vcd",
.description = "Value Change Dump (VCD)",
.df_type = SR_DF_LOGIC,
.init = init,
.receive = receive,
.cleanup = cleanup,
};