-/*
- * This file is part of the sigrok project.
- *
- * Copyright (C) 2012 Petteri Aimonen <jpa@sr.mail.kapsi.fi>
- *
- * 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 3 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, see <http://www.gnu.org/licenses/>.
- */
-
-/* The VCD input module has the following options:
- *
- * numprobes: Maximum number of probes to use. The probes are
- * detected in the same order as they are listed
- * in the $var sections of the VCD file.
- *
- * skip: Allows skipping until given timestamp in the file.
- * This can speed up analyzing of long captures.
- *
- * Value < 0: Skip until first timestamp listed in
- * the file. (default)
- *
- * Value = 0: Do not skip, instead generate samples
- * beginning from timestamp 0.
- *
- * Value > 0: Start at the given timestamp.
- *
- * downsample: Divide the samplerate by the given factor.
- * This can speed up analyzing of long captures.
- *
- * compress: Compress idle periods longer than this value.
- * This can speed up analyzing of long captures.
- * Default 0 = don't compress.
- *
- * Based on Verilog standard IEEE Std 1364-2001 Version C
- *
- * Supported features:
- * - $var with 'wire' and 'reg' types of scalar variables
- * - $timescale definition for samplerate
- * - multiple character variable identifiers
- *
- * Most important unsupported features:
- * - vector variables (bit vectors etc.)
- * - analog, integer and real number variables
- * - $dumpvars initial value declaration
- * - $scope namespaces
- */
-
-/* */
-
-#include <stdlib.h>
-#include <glib.h>
-#include <stdio.h>
-#include <string.h>
-#include "libsigrok.h"
-#include "libsigrok-internal.h"
-
-/* Message logging helpers with driver-specific prefix string. */
-#define DRIVER_LOG_DOMAIN "input/vcd: "
-#define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args)
-#define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args)
-#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args)
-
-#define DEFAULT_NUM_PROBES 8
-
-/* Read until specific type of character occurs in file.
- * Skip input if dest is NULL.
- * Modes:
- * 'W' read until whitespace
- * 'N' read until non-whitespace, and ungetc() the character
- * '$' read until $end
- */
-static gboolean read_until(FILE *file, GString *dest, char mode)
-{
- char prev[4] = "";
- long startpos = ftell(file);
- for(;;)
- {
- int c = fgetc(file);
-
- if (c == EOF)
- {
- if (mode == '$')
- sr_err("Unexpected EOF, read started at %ld.", startpos);
- return FALSE;
- }
-
- if (mode == 'W' && g_ascii_isspace(c))
- return TRUE;
-
- if (mode == 'N' && !g_ascii_isspace(c))
- {
- ungetc(c, file);
- return TRUE;
- }
-
- if (mode == '$')
- {
- prev[0] = prev[1]; prev[1] = prev[2]; prev[2] = prev[3]; prev[3] = c;
- if (prev[0] == '$' && prev[1] == 'e' && prev[2] == 'n' && prev[3] == 'd')
- {
- if (dest != NULL)
- g_string_truncate(dest, dest->len - 3);
-
- return TRUE;
- }
- }
-
- if (dest != NULL)
- g_string_append_c(dest, c);
- }
-}
-
-/* Reads a single VCD section from input file and parses it to structure.
- * e.g. $timescale 1ps $end => "timescale" "1ps"
- */
-static gboolean parse_section(FILE *file, gchar **name, gchar **contents)
-{
- gboolean status;
- GString *sname, *scontents;
-
- /* Skip any initial white-space */
- if (!read_until(file, NULL, 'N')) return FALSE;
-
- /* Section tag should start with $. */
- if (fgetc(file) != '$')
- {
- sr_err("Expected $ at beginning of section.");
- return FALSE;
- }
-
- /* Read the section tag */
- sname = g_string_sized_new(32);
- status = read_until(file, sname, 'W');
-
- /* Skip whitespace before content */
- status = status && read_until(file, NULL, 'N');
-
- /* Read the content */
- scontents = g_string_sized_new(128);
- status = status && read_until(file, scontents, '$');
- g_strchomp(scontents->str);
-
- /* Release strings if status is FALSE, return them if status is TRUE */
- *name = g_string_free(sname, !status);
- *contents = g_string_free(scontents, !status);
- return status;
-}
-
-struct probe
-{
- gchar *name;
- gchar *identifier;
-};
-
-struct context
-{
- uint64_t samplerate;
- int maxprobes;
- int probecount;
- int downsample;
- unsigned compress;
- int64_t skip;
- struct probe probes[SR_MAX_NUM_PROBES];
-};
-
-static void release_context(struct context *ctx)
-{
- int i;
- for (i = 0; i < ctx->probecount; i++)
- {
- g_free(ctx->probes[i].name); ctx->probes[i].name = NULL;
- g_free(ctx->probes[i].identifier); ctx->probes[i].identifier = NULL;
- }
-
- g_free(ctx);
-}
-
-/* Remove empty parts from an array returned by g_strsplit. */
-static void remove_empty_parts(gchar **parts)
-{
- gchar **src = parts;
- gchar **dest = parts;
- while (*src != NULL)
- {
- if (**src != '\0')
- {
- *dest++ = *src;
- }
-
- src++;
- }
-
- *dest = NULL;
-}
-
-/* Parse VCD header to get values for context structure.
- * The context structure should be zeroed before calling this.
- */
-static gboolean parse_header(FILE *file, struct context *ctx)
-{
- gchar *name = NULL, *contents = NULL;
- gboolean status = FALSE;
-
- while (parse_section(file, &name, &contents))
- {
- sr_dbg("Section '%s', contents '%s'.", name, contents);
-
- if (g_strcmp0(name, "enddefinitions") == 0)
- {
- status = TRUE;
- break;
- }
- else if (g_strcmp0(name, "timescale") == 0)
- {
- /* The standard allows for values 1, 10 or 100
- * and units s, ms, us, ns, ps and fs. */
- struct sr_rational period;
- if (sr_parse_period(contents, &period) == SR_OK)
- {
- ctx->samplerate = period.q / period.p;
- if (period.q % period.p != 0)
- {
- /* Does not happen unless time value is non-standard */
- sr_warn("Inexact rounding of samplerate, %" PRIu64 " / %" PRIu64 " to %" PRIu64 " Hz.",
- period.q, period.p, ctx->samplerate);
- }
-
- sr_dbg("Samplerate: %" PRIu64, ctx->samplerate);
- }
- else
- {
- sr_err("Parsing timescale failed.");
- }
- }
- else if (g_strcmp0(name, "var") == 0)
- {
- /* Format: $var type size identifier reference $end */
- gchar **parts = g_strsplit_set(contents, " \r\n\t", 0);
- remove_empty_parts(parts);
-
- if (g_strv_length(parts) != 4)
- {
- sr_warn("$var section should have 4 items");
- }
- else if (g_strcmp0(parts[0], "reg") != 0 && g_strcmp0(parts[0], "wire") != 0)
- {
- sr_info("Unsupported signal type: '%s'", parts[0]);
- }
- else if (strtol(parts[1], NULL, 10) != 1)
- {
- sr_info("Unsupported signal size: '%s'", parts[1]);
- }
- else if (ctx->probecount >= ctx->maxprobes)
- {
- sr_warn("Skipping '%s' because only %d probes requested.", parts[3], ctx->maxprobes);
- }
- else
- {
- sr_info("Probe %d is '%s' identified by '%s'.", ctx->probecount, parts[3], parts[2]);
- ctx->probes[ctx->probecount].identifier = g_strdup(parts[2]);
- ctx->probes[ctx->probecount].name = g_strdup(parts[3]);
- ctx->probecount++;
- }
-
- g_strfreev(parts);
- }
-
- g_free(name); name = NULL;
- g_free(contents); contents = NULL;
- }
-
- g_free(name);
- g_free(contents);
-
- return status;
-}
-
-static int format_match(const char *filename)
-{
- FILE *file;
- gchar *name = NULL, *contents = NULL;
- gboolean status;
-
- file = fopen(filename, "r");
- if (file == NULL)
- return FALSE;
-
- /* If we can parse the first section correctly,
- * then it is assumed to be a VCD file.
- */
- status = parse_section(file, &name, &contents);
- status = status && (*name != '\0');
-
- g_free(name);
- g_free(contents);
- fclose(file);
-
- return status;
-}
-
-static int init(struct sr_input *in, const char *filename)
-{
- struct sr_probe *probe;
- int num_probes, i;
- char name[SR_MAX_PROBENAME_LEN + 1];
- char *param;
- struct context *ctx;
-
- (void)filename;
-
- if (!(ctx = g_try_malloc0(sizeof(*ctx)))) {
- sr_err("Input format context malloc failed.");
- return SR_ERR_MALLOC;
- }
-
- num_probes = DEFAULT_NUM_PROBES;
- ctx->samplerate = 0;
- ctx->downsample = 1;
- ctx->skip = -1;
-
- if (in->param) {
- param = g_hash_table_lookup(in->param, "numprobes");
- if (param) {
- num_probes = strtoul(param, NULL, 10);
- if (num_probes < 1)
- {
- release_context(ctx);
- return SR_ERR;
- }
- }
-
- param = g_hash_table_lookup(in->param, "downsample");
- if (param) {
- ctx->downsample = strtoul(param, NULL, 10);
- if (ctx->downsample < 1)
- {
- ctx->downsample = 1;
- }
- }
-
- param = g_hash_table_lookup(in->param, "compress");
- if (param) {
- ctx->compress = strtoul(param, NULL, 10);
- }
-
- param = g_hash_table_lookup(in->param, "skip");
- if (param) {
- ctx->skip = strtoul(param, NULL, 10) / ctx->downsample;
- }
- }
-
- /* Maximum number of probes to parse from the VCD */
- ctx->maxprobes = num_probes;
-
- /* Create a virtual device. */
- in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL);
- in->internal = ctx;
-
- for (i = 0; i < num_probes; i++) {
- snprintf(name, SR_MAX_PROBENAME_LEN, "%d", i);
-
- if (!(probe = sr_probe_new(i, SR_PROBE_LOGIC, TRUE, name)))
- {
- release_context(ctx);
- return SR_ERR;
- }
-
- in->sdi->probes = g_slist_append(in->sdi->probes, probe);
- }
-
- return SR_OK;
-}
-
-#define CHUNKSIZE 1024
-
-/* Send N samples of the given value. */
-static void send_samples(const struct sr_dev_inst *sdi, uint64_t sample, uint64_t count)
-{
- struct sr_datafeed_packet packet;
- struct sr_datafeed_logic logic;
- uint64_t buffer[CHUNKSIZE];
- uint64_t i;
- unsigned chunksize = CHUNKSIZE;
-
- if (count < chunksize)
- chunksize = count;
-
- for (i = 0; i < chunksize; i++)
- {
- buffer[i] = sample;
- }
-
- packet.type = SR_DF_LOGIC;
- packet.payload = &logic;
- logic.unitsize = sizeof(uint64_t);
- logic.data = buffer;
-
- while (count)
- {
- if (count < chunksize)
- chunksize = count;
-
- logic.length = sizeof(uint64_t) * chunksize;
-
- sr_session_send(sdi, &packet);
- count -= chunksize;
- }
-}
-
-/* Parse the data section of VCD */
-static void parse_contents(FILE *file, const struct sr_dev_inst *sdi, struct context *ctx)
-{
- GString *token = g_string_sized_new(32);
-
- uint64_t prev_timestamp = 0;
- uint64_t prev_values = 0;
-
- /* Read one space-delimited token at a time. */
- while (read_until(file, NULL, 'N') && read_until(file, token, 'W'))
- {
- if (token->str[0] == '#' && g_ascii_isdigit(token->str[1]))
- {
- /* Numeric value beginning with # is a new timestamp value */
- uint64_t timestamp;
- timestamp = strtoull(token->str + 1, NULL, 10);
-
- if (ctx->downsample > 1)
- timestamp /= ctx->downsample;
-
- /* Skip < 0 => skip until first timestamp.
- * Skip = 0 => don't skip
- * Skip > 0 => skip until timestamp >= skip.
- */
- if (ctx->skip < 0)
- {
- ctx->skip = timestamp;
- prev_timestamp = timestamp;
- }
- else if (ctx->skip > 0 && timestamp < (uint64_t)ctx->skip)
- {
- prev_timestamp = ctx->skip;
- }
- else if (timestamp == prev_timestamp)
- {
- /* Ignore repeated timestamps (e.g. sigrok outputs these) */
- }
- else
- {
- if (ctx->compress != 0 && timestamp - prev_timestamp > ctx->compress)
- {
- /* Compress long idle periods */
- prev_timestamp = timestamp - ctx->compress;
- }
-
- sr_dbg("New timestamp: %" PRIu64, timestamp);
-
- /* Generate samples from prev_timestamp up to timestamp - 1. */
- send_samples(sdi, prev_values, timestamp - prev_timestamp);
- prev_timestamp = timestamp;
- }
- }
- else if (token->str[0] == '$' && token->len > 1)
- {
- /* This is probably a $dumpvars, $comment or similar.
- * $dump* contain useful data, but other tags will be skipped until $end. */
- if (g_strcmp0(token->str, "$dumpvars") == 0 ||
- g_strcmp0(token->str, "$dumpon") == 0 ||
- g_strcmp0(token->str, "$dumpoff") == 0 ||
- g_strcmp0(token->str, "$end") == 0)
- {
- /* Ignore, parse contents as normally. */
- }
- else
- {
- /* Skip until $end */
- read_until(file, NULL, '$');
- }
- }
- else if (strchr("bBrR", token->str[0]) != NULL)
- {
- /* A vector value. Skip it and also the following identifier. */
- read_until(file, NULL, 'N');
- read_until(file, NULL, 'W');
- }
- else if (strchr("01xXzZ", token->str[0]) != NULL)
- {
- /* A new 1-bit sample value */
- int i, bit;
- bit = (token->str[0] == '1');
-
- g_string_erase(token, 0, 1);
- if (token->len == 0)
- {
- /* There was a space between value and identifier.
- * Read in the rest.
- */
- read_until(file, NULL, 'N');
- read_until(file, token, 'W');
- }
-
- for (i = 0; i < ctx->probecount; i++)
- {
- if (g_strcmp0(token->str, ctx->probes[i].identifier) == 0)
- {
- sr_dbg("Probe %d new value %d.", i, bit);
-
- /* Found our probe */
- if (bit)
- prev_values |= (1 << i);
- else
- prev_values &= ~(1 << i);
-
- break;
- }
- }
-
- if (i == ctx->probecount)
- {
- sr_dbg("Did not find probe for identifier '%s'.", token->str);
- }
- }
- else
- {
- sr_warn("Skipping unknown token '%s'.", token->str);
- }
-
- g_string_truncate(token, 0);
- }
-
- g_string_free(token, TRUE);
-}
-
-static int loadfile(struct sr_input *in, const char *filename)
-{
- struct sr_datafeed_packet packet;
- struct sr_datafeed_meta meta;
- struct sr_config *src;
- FILE *file;
- struct context *ctx;
- uint64_t samplerate;
-
- ctx = in->internal;
-
- if ((file = fopen(filename, "r")) == NULL)
- return SR_ERR;
-
- if (!parse_header(file, ctx))
- {
- sr_err("VCD parsing failed");
- fclose(file);
- return SR_ERR;
- }
-
- /* Send header packet to the session bus. */
- std_session_send_df_header(in->sdi, DRIVER_LOG_DOMAIN);
-
- /* Send metadata about the SR_DF_LOGIC packets to come. */
- packet.type = SR_DF_META;
- packet.payload = &meta;
- samplerate = ctx->samplerate / ctx->downsample;
- src = sr_config_make(SR_CONF_SAMPLERATE, (const void *)&samplerate);
- meta.config = g_slist_append(NULL, src);
- sr_session_send(in->sdi, &packet);
-
- /* Parse the contents of the VCD file */
- parse_contents(file, in->sdi, ctx);
-
- /* Send end packet to the session bus. */
- packet.type = SR_DF_END;
- sr_session_send(in->sdi, &packet);
-
- fclose(file);
- release_context(ctx);
- in->internal = NULL;
-
- return SR_OK;
-}
-
-SR_PRIV struct sr_input_format input_vcd = {
- .id = "vcd",
- .description = "Value Change Dump",
- .format_match = format_match,
- .init = init,
- .loadfile = loadfile,
-};