+++ /dev/null
-/*
- * This file is part of the libsigrok project.
- *
- * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.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 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/>.
- */
-
-#include "protocol.h"
-
-static void handle_packet(const uint8_t *buf, struct sr_dev_inst *sdi)
-{
- float floatval;
- struct dev_context *devc;
- struct sr_datafeed_packet packet;
- struct sr_datafeed_analog analog;
-
- devc = sdi->priv;
-
- analog.num_samples = 1;
- analog.mq = -1;
-
- if (brymen_parse(buf, &floatval, &analog, NULL) != SR_OK)
- return;
- analog.data = &floatval;
-
- analog.channels = sdi->channels;
-
- if (analog.mq != -1) {
- /* Got a measurement. */
- packet.type = SR_DF_ANALOG;
- packet.payload = &analog;
- sr_session_send(devc->cb_data, &packet);
- devc->num_samples++;
- }
-}
-
-static void handle_new_data(struct sr_dev_inst *sdi)
-{
- struct dev_context *devc;
- int len, status, offset = 0;
- struct sr_serial_dev_inst *serial;
-
- devc = sdi->priv;
- serial = sdi->conn;
-
- /* Try to get as much data as the buffer can hold. */
- len = DMM_BUFSIZE - devc->buflen;
- len = serial_read(serial, devc->buf + devc->buflen, len);
- if (len < 1) {
- sr_err("Serial port read error: %d.", len);
- return;
- }
- devc->buflen += len;
- status = PACKET_INVALID_HEADER;
-
- /* Now look for packets in that data. */
- while (status != PACKET_NEED_MORE_DATA) {
- /* We don't have a header, look for one. */
- if (devc->next_packet_len == 0) {
- len = devc->buflen - offset;
- status = brymen_packet_length(devc->buf + offset, &len);
- if (status == PACKET_HEADER_OK) {
- /* We know how large the packet will be. */
- devc->next_packet_len = len;
- } else if (status == PACKET_NEED_MORE_DATA) {
- /* We didn't yet receive the full header. */
- devc->next_packet_len = 0;
- break;
- } else {
- /* Invalid header. Move on. */
- devc->next_packet_len = 0;
- offset++;
- continue;
- }
- }
-
- /* We know how the packet size, but did we receive all of it? */
- if (devc->buflen - offset < devc->next_packet_len)
- break;
-
- /* We should have a full packet here, so we can check it. */
- if (brymen_packet_is_valid(devc->buf + offset)) {
- handle_packet(devc->buf + offset, sdi);
- offset += devc->next_packet_len;
- } else {
- offset++;
- }
-
- /* We are done with this packet. Look for a new one. */
- devc->next_packet_len = 0;
- }
-
- /* If we have any data left, move it to the beginning of our buffer. */
- memmove(devc->buf, devc->buf + offset, devc->buflen - offset);
- devc->buflen -= offset;
-}
-
-SR_PRIV int brymen_dmm_receive_data(int fd, int revents, void *cb_data)
-{
- struct sr_dev_inst *sdi;
- struct dev_context *devc;
- struct sr_serial_dev_inst *serial;
- int ret;
- int64_t time;
-
- (void)fd;
-
- if (!(sdi = cb_data))
- return TRUE;
-
- if (!(devc = sdi->priv))
- return TRUE;
-
- serial = sdi->conn;
-
- if (revents == G_IO_IN) {
- /* Serial data arrived. */
- handle_new_data(sdi);
- } else {
- /* Timeout, send another packet request. */
- if ((ret = brymen_packet_request(serial)) < 0) {
- sr_err("Failed to request packet: %d.", ret);
- return FALSE;
- }
- }
-
- if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
- sr_info("Requested number of samples reached, stopping.");
- sdi->driver->dev_acquisition_stop(sdi, cb_data);
- return TRUE;
- }
-
- if (devc->limit_msec) {
- time = (g_get_monotonic_time() - devc->starttime) / 1000;
- if (time > (int64_t)devc->limit_msec) {
- sr_info("Requested time limit reached, stopping.");
- sdi->driver->dev_acquisition_stop(sdi, cb_data);
- return TRUE;
- }
- }
-
- return TRUE;
-}
-
-/**
- * Try to find a valid packet in a serial data stream.
- *
- * @param serial Previously initialized serial port structure.
- * @param buf Buffer containing the bytes to write.
- * @param buflen Size of the buffer.
- * @param get_packet_size Callback that assesses the size of incoming packets.
- * @param is_valid Callback that assesses whether the packet is valid or not.
- * @param timeout_ms The timeout after which, if no packet is detected, to
- * abort scanning.
- * @param baudrate The baudrate of the serial port. This parameter is not
- * critical, but it helps fine tune the serial port polling
- * delay.
- *
- * @return SR_OK if a valid packet is found within the given timeout,
- * SR_ERR upon failure.
- */
-SR_PRIV int brymen_stream_detect(struct sr_serial_dev_inst *serial,
- uint8_t *buf, size_t *buflen,
- packet_length_t get_packet_size,
- packet_valid_callback is_valid,
- uint64_t timeout_ms, int baudrate)
-{
- int64_t start, time, byte_delay_us;
- size_t ibuf, i, maxlen;
- int status, len, packet_len, stream_len;
-
- maxlen = *buflen;
-
- sr_dbg("Detecting packets on %s (timeout = %" PRIu64
- "ms, baudrate = %d).", serial->port, timeout_ms, baudrate);
-
- /* Assume 8n1 transmission. That is 10 bits for every byte. */
- byte_delay_us = 10 * (1000000 / baudrate);
- start = g_get_monotonic_time();
-
- packet_len = i = ibuf = len = 0;
- while (ibuf < maxlen) {
- len = serial_read(serial, &buf[ibuf], maxlen - ibuf);
- if (len > 0) {
- ibuf += len;
- sr_spew("Read %d bytes.", len);
- }
-
- time = g_get_monotonic_time() - start;
- time /= 1000;
-
- stream_len = ibuf - i;
- if (stream_len > 0 && packet_len == 0) {
- /* How large of a packet are we expecting? */
- packet_len = stream_len;
- status = get_packet_size(&buf[i], &packet_len);
- switch(status) {
- case PACKET_HEADER_OK:
- /* We know how much data we need to wait for. */
- break;
- case PACKET_NEED_MORE_DATA:
- /* We did not receive the full header. */
- packet_len = 0;
- break;
- case PACKET_INVALID_HEADER:
- default:
- /*
- * We had enough data, but here was an error in
- * parsing the header. Restart parsing from the
- * next byte.
- */
- packet_len = 0;
- i++;
- break;
- }
- }
-
- if ((stream_len >= packet_len) && (packet_len != 0)) {
- /* We have at least a packet's worth of data. */
- if (is_valid(&buf[i])) {
- sr_spew("Found valid %d-byte packet after "
- "%" PRIu64 "ms.", packet_len, time);
- *buflen = ibuf;
- return SR_OK;
- } else {
- sr_spew("Got %d bytes, but not a valid "
- "packet.", packet_len);
-
- }
-
- /* Not a valid packet. Continue searching. */
- i++;
- packet_len = 0;
- }
-
- if (time >= (int64_t)timeout_ms) {
- /* Timeout */
- sr_dbg("Detection timed out after %dms.", time);
- break;
- }
- g_usleep(byte_delay_us);
- }
-
- *buflen = ibuf;
- sr_err("Didn't find a valid packet (read %d bytes).", ibuf);
-
- return SR_ERR;
-}
projects / libsigrok.git / blobdiff