2 * This file is part of the libsigrok project.
4 * Copyright (C) 2012 Petteri Aimonen <jpa@sr.mail.kapsi.fi>
5 * Copyright (C) 2014 Bert Vermeulen <bert@biot.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 /* The VCD input module has the following options:
23 * numchannels: Maximum number of channels to use. The channels are
24 * detected in the same order as they are listed
25 * in the $var sections of the VCD file.
27 * skip: Allows skipping until given timestamp in the file.
28 * This can speed up analyzing of long captures.
30 * Value < 0: Skip until first timestamp listed in
33 * Value = 0: Do not skip, instead generate samples
34 * beginning from timestamp 0.
36 * Value > 0: Start at the given timestamp.
38 * downsample: Divide the samplerate by the given factor.
39 * This can speed up analyzing of long captures.
41 * compress: Compress idle periods longer than this value.
42 * This can speed up analyzing of long captures.
43 * Default 0 = don't compress.
45 * Based on Verilog standard IEEE Std 1364-2001 Version C
48 * - $var with 'wire' and 'reg' types of scalar variables
49 * - $timescale definition for samplerate
50 * - multiple character variable identifiers
52 * Most important unsupported features:
53 * - vector variables (bit vectors etc.)
54 * - analog, integer and real number variables
55 * - $dumpvars initial value declaration
57 * - more than 64 channels
65 #include <libsigrok/libsigrok.h>
66 #include "libsigrok-internal.h"
68 #define LOG_PREFIX "input/vcd"
70 #define DEFAULT_NUM_CHANNELS 8
71 #define CHUNKSIZE (1024 * 1024)
77 unsigned int maxchannels;
78 unsigned int channelcount;
82 gboolean skip_until_end;
84 size_t bytes_per_sample;
85 size_t samples_in_buffer;
87 uint8_t *current_levels;
96 * Reads a single VCD section from input file and parses it to name/contents.
97 * e.g. $timescale 1ps $end => "timescale" "1ps"
99 static gboolean parse_section(GString *buf, gchar **name, gchar **contents)
101 GString *sname, *scontent;
105 *name = *contents = NULL;
109 /* Skip any initial white-space. */
110 while (pos < buf->len && g_ascii_isspace(buf->str[pos]))
113 /* Section tag should start with $. */
114 if (buf->str[pos++] != '$')
117 sname = g_string_sized_new(32);
118 scontent = g_string_sized_new(128);
120 /* Read the section tag. */
121 while (pos < buf->len && !g_ascii_isspace(buf->str[pos]))
122 g_string_append_c(sname, buf->str[pos++]);
124 /* Skip whitespace before content. */
125 while (pos < buf->len && g_ascii_isspace(buf->str[pos]))
128 /* Read the content. */
129 while (pos < buf->len - 4 && strncmp(buf->str + pos, "$end", 4))
130 g_string_append_c(scontent, buf->str[pos++]);
132 if (sname->len && pos < buf->len - 4 && !strncmp(buf->str + pos, "$end", 4)) {
135 while (pos < buf->len && g_ascii_isspace(buf->str[pos]))
137 g_string_erase(buf, 0, pos);
140 *name = g_string_free(sname, !status);
141 *contents = g_string_free(scontent, !status);
143 g_strchomp(*contents);
148 static void free_channel(void *data)
150 struct vcd_channel *vcd_ch = data;
151 g_free(vcd_ch->name);
152 g_free(vcd_ch->identifier);
156 /* Remove empty parts from an array returned by g_strsplit. */
157 static void remove_empty_parts(gchar **parts)
160 gchar **dest = parts;
161 while (*src != NULL) {
171 * Parse VCD header to get values for context structure.
172 * The context structure should be zeroed before calling this.
174 static gboolean parse_header(const struct sr_input *in, GString *buf)
176 struct vcd_channel *vcd_ch;
180 gchar *name, *contents, **parts;
183 name = contents = NULL;
185 while (parse_section(buf, &name, &contents)) {
186 sr_dbg("Section '%s', contents '%s'.", name, contents);
188 if (g_strcmp0(name, "enddefinitions") == 0) {
191 } else if (g_strcmp0(name, "timescale") == 0) {
193 * The standard allows for values 1, 10 or 100
194 * and units s, ms, us, ns, ps and fs.
196 if (sr_parse_period(contents, &p, &q) == SR_OK) {
197 inc->samplerate = q / p;
199 /* Does not happen unless time value is non-standard */
200 sr_warn("Inexact rounding of samplerate, %" PRIu64 " / %" PRIu64 " to %" PRIu64 " Hz.",
201 q, p, inc->samplerate);
204 sr_dbg("Samplerate: %" PRIu64, inc->samplerate);
206 sr_err("Parsing timescale failed.");
208 } else if (g_strcmp0(name, "var") == 0) {
209 /* Format: $var type size identifier reference $end */
210 parts = g_strsplit_set(contents, " \r\n\t", 0);
211 remove_empty_parts(parts);
213 if (g_strv_length(parts) != 4)
214 sr_warn("$var section should have 4 items");
215 else if (g_strcmp0(parts[0], "reg") != 0 && g_strcmp0(parts[0], "wire") != 0)
216 sr_info("Unsupported signal type: '%s'", parts[0]);
217 else if (strtol(parts[1], NULL, 10) != 1)
218 sr_info("Unsupported signal size: '%s'", parts[1]);
219 else if (inc->channelcount >= inc->maxchannels)
220 sr_warn("Skipping '%s' because only %d channels requested.",
221 parts[3], inc->maxchannels);
223 sr_info("Channel %d is '%s' identified by '%s'.",
224 inc->channelcount, parts[3], parts[2]);
225 vcd_ch = g_malloc(sizeof(struct vcd_channel));
226 vcd_ch->identifier = g_strdup(parts[2]);
227 vcd_ch->name = g_strdup(parts[3]);
228 inc->channels = g_slist_append(inc->channels, vcd_ch);
244 * Compute how many bytes each sample will have and initialize the
245 * current levels. The current levels will be updated whenever VCD
248 inc->bytes_per_sample = (inc->channelcount + 7) / 8;
249 inc->current_levels = g_malloc0(inc->bytes_per_sample);
251 inc->got_header = status;
256 static int format_match(GHashTable *metadata)
258 GString *buf, *tmpbuf;
260 gchar *name, *contents;
262 buf = g_hash_table_lookup(metadata, GINT_TO_POINTER(SR_INPUT_META_HEADER));
263 tmpbuf = g_string_new_len(buf->str, buf->len);
266 * If we can parse the first section correctly,
267 * then it is assumed to be a VCD file.
269 status = parse_section(tmpbuf, &name, &contents);
270 g_string_free(tmpbuf, TRUE);
274 return status ? SR_OK : SR_ERR;
277 /* Send all accumulated bytes from inc->buffer. */
278 static void send_buffer(const struct sr_input *in)
281 struct sr_datafeed_packet packet;
282 struct sr_datafeed_logic logic;
286 if (inc->samples_in_buffer == 0)
289 packet.type = SR_DF_LOGIC;
290 packet.payload = &logic;
291 logic.unitsize = inc->bytes_per_sample;
292 logic.data = inc->buffer;
293 logic.length = inc->bytes_per_sample * inc->samples_in_buffer;
294 sr_session_send(in->sdi, &packet);
295 inc->samples_in_buffer = 0;
299 * Add N copies of the current sample to buffer.
300 * When the buffer fills up, automatically send it.
302 static void add_samples(const struct sr_input *in, size_t count)
305 size_t samples_per_chunk;
306 size_t space_left, i;
310 samples_per_chunk = CHUNKSIZE / inc->bytes_per_sample;
313 space_left = samples_per_chunk - inc->samples_in_buffer;
315 if (space_left > count)
318 p = inc->buffer + inc->samples_in_buffer * inc->bytes_per_sample;
319 for (i = 0; i < space_left; i++) {
320 memcpy(p, inc->current_levels, inc->bytes_per_sample);
321 p += inc->bytes_per_sample;
322 inc->samples_in_buffer++;
326 if (inc->samples_in_buffer == samples_per_chunk)
331 /* Parse a set of lines from the data section. */
332 static void parse_contents(const struct sr_input *in, char *data)
335 struct vcd_channel *vcd_ch;
337 uint64_t timestamp, prev_timestamp;
338 unsigned int bit, i, j;
344 /* Read one space-delimited token at a time. */
345 tokens = g_strsplit_set(data, " \t\r\n", 0);
346 remove_empty_parts(tokens);
347 for (i = 0; tokens[i]; i++) {
348 if (inc->skip_until_end) {
349 if (!strcmp(tokens[i], "$end")) {
350 /* Done with unhandled/unknown section. */
351 inc->skip_until_end = FALSE;
355 if (tokens[i][0] == '#' && g_ascii_isdigit(tokens[i][1])) {
356 /* Numeric value beginning with # is a new timestamp value */
357 timestamp = strtoull(tokens[i] + 1, NULL, 10);
359 if (inc->downsample > 1)
360 timestamp /= inc->downsample;
363 * Skip < 0 => skip until first timestamp.
364 * Skip = 0 => don't skip
365 * Skip > 0 => skip until timestamp >= skip.
368 inc->skip = timestamp;
369 prev_timestamp = timestamp;
370 } else if (inc->skip > 0 && timestamp < (uint64_t)inc->skip) {
371 prev_timestamp = inc->skip;
372 } else if (timestamp == prev_timestamp) {
373 /* Ignore repeated timestamps (e.g. sigrok outputs these) */
375 if (inc->compress != 0 && timestamp - prev_timestamp > inc->compress) {
376 /* Compress long idle periods */
377 prev_timestamp = timestamp - inc->compress;
380 sr_dbg("New timestamp: %" PRIu64, timestamp);
382 /* Generate samples from prev_timestamp up to timestamp - 1. */
383 add_samples(in, timestamp - prev_timestamp);
384 prev_timestamp = timestamp;
386 } else if (tokens[i][0] == '$' && tokens[i][1] != '\0') {
388 * This is probably a $dumpvars, $comment or similar.
389 * $dump* contain useful data.
391 if (g_strcmp0(tokens[i], "$dumpvars") == 0
392 || g_strcmp0(tokens[i], "$dumpon") == 0
393 || g_strcmp0(tokens[i], "$dumpoff") == 0
394 || g_strcmp0(tokens[i], "$end") == 0) {
395 /* Ignore, parse contents as normally. */
397 /* Ignore this and future lines until $end. */
398 inc->skip_until_end = TRUE;
401 } else if (strchr("bBrR", tokens[i][0]) != NULL) {
402 /* A vector value, not supported yet. */
404 } else if (strchr("01xXzZ", tokens[i][0]) != NULL) {
405 /* A new 1-bit sample value */
406 bit = (tokens[i][0] == '1');
409 * The identifier is either the next character, or, if
410 * there was whitespace after the bit, the next token.
412 if (tokens[i][1] == '\0') {
414 /* Missing identifier */
417 for (j = 1; tokens[i][j]; j++)
418 tokens[i][j - 1] = tokens[i][j];
419 tokens[i][j - 1] = '\0';
422 for (j = 0, l = inc->channels; j < inc->channelcount && l; j++, l = l->next) {
424 if (g_strcmp0(tokens[i], vcd_ch->identifier) == 0) {
425 /* Found our channel */
426 size_t byte_idx = (j / 8);
427 size_t bit_idx = j - 8 * byte_idx;
429 inc->current_levels[byte_idx] |= (uint8_t)1 << bit_idx;
431 inc->current_levels[byte_idx] &= ~((uint8_t)1 << bit_idx);
435 if (j == inc->channelcount)
436 sr_dbg("Did not find channel for identifier '%s'.", tokens[i]);
438 sr_warn("Skipping unknown token '%s'.", tokens[i]);
444 static int init(struct sr_input *in, GHashTable *options)
450 num_channels = g_variant_get_int32(g_hash_table_lookup(options, "numchannels"));
451 if (num_channels < 1) {
452 sr_err("Invalid value for numchannels: must be at least 1.");
455 inc = in->priv = g_malloc0(sizeof(struct context));
456 inc->maxchannels = num_channels;
458 inc->downsample = g_variant_get_int32(g_hash_table_lookup(options, "downsample"));
459 if (inc->downsample < 1)
462 inc->compress = g_variant_get_int32(g_hash_table_lookup(options, "compress"));
463 inc->skip = g_variant_get_int32(g_hash_table_lookup(options, "skip"));
464 inc->skip /= inc->downsample;
466 in->sdi = g_malloc0(sizeof(struct sr_dev_inst));
469 inc->buffer = g_malloc(CHUNKSIZE);
471 for (i = 0; i < num_channels; i++) {
472 snprintf(name, 16, "%d", i);
473 sr_channel_new(in->sdi, i, SR_CHANNEL_LOGIC, TRUE, name);
479 static gboolean have_header(GString *buf)
484 if (!(p = g_strstr_len(buf->str, buf->len, "$enddefinitions")))
486 pos = p - buf->str + 15;
487 while (pos < buf->len - 4 && g_ascii_isspace(buf->str[pos]))
489 if (!strncmp(buf->str + pos, "$end", 4))
495 static int process_buffer(struct sr_input *in)
497 struct sr_datafeed_packet packet;
498 struct sr_datafeed_meta meta;
499 struct sr_config *src;
506 std_session_send_df_header(in->sdi, LOG_PREFIX);
508 packet.type = SR_DF_META;
509 packet.payload = &meta;
510 samplerate = inc->samplerate / inc->downsample;
511 src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(samplerate));
512 meta.config = g_slist_append(NULL, src);
513 sr_session_send(in->sdi, &packet);
514 g_slist_free(meta.config);
520 while ((p = g_strrstr_len(in->buf->str, in->buf->len, "\n"))) {
522 g_strstrip(in->buf->str);
523 if (in->buf->str[0] != '\0')
524 parse_contents(in, in->buf->str);
525 g_string_erase(in->buf, 0, p - in->buf->str + 1);
531 static int receive(struct sr_input *in, GString *buf)
536 g_string_append_len(in->buf, buf->str, buf->len);
539 if (!inc->got_header) {
540 if (!have_header(in->buf))
542 if (!parse_header(in, in->buf))
543 /* There was a header in there, but it was malformed. */
546 in->sdi_ready = TRUE;
547 /* sdi is ready, notify frontend. */
551 ret = process_buffer(in);
556 static int end(struct sr_input *in)
558 struct sr_datafeed_packet packet;
565 ret = process_buffer(in);
569 /* Send any samples that haven't been sent yet. */
573 packet.type = SR_DF_END;
574 sr_session_send(in->sdi, &packet);
580 static void cleanup(struct sr_input *in)
585 g_slist_free_full(inc->channels, free_channel);
588 g_free(inc->current_levels);
589 inc->current_levels = NULL;
592 static struct sr_option options[] = {
593 { "numchannels", "Number of channels", "Number of channels", NULL, NULL },
594 { "skip", "Skip", "Skip until timestamp", NULL, NULL },
595 { "downsample", "Downsample", "Divide samplerate by factor", NULL, NULL },
596 { "compress", "Compress", "Compress idle periods longer than this value", NULL, NULL },
600 static const struct sr_option *get_options(void)
602 if (!options[0].def) {
603 options[0].def = g_variant_ref_sink(g_variant_new_int32(DEFAULT_NUM_CHANNELS));
604 options[1].def = g_variant_ref_sink(g_variant_new_int32(-1));
605 options[2].def = g_variant_ref_sink(g_variant_new_int32(1));
606 options[3].def = g_variant_ref_sink(g_variant_new_int32(0));
612 SR_PRIV struct sr_input_module input_vcd = {
615 .desc = "Value Change Dump",
616 .exts = (const char*[]){"vcd", NULL},
617 .metadata = { SR_INPUT_META_HEADER | SR_INPUT_META_REQUIRED },
618 .options = get_options,
619 .format_match = format_match,