hardware/common/scpi_tcp.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 Martin Ling <martin-sigrok@earth.li>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifdef _WIN32
  21 #define _WIN32_WINNT 0x0501
  22 #include <winsock2.h>
  23 #include <ws2tcpip.h>
  24 #endif
  25
  26 #include "libsigrok.h"
  27 #include "libsigrok-internal.h"
  28
  29 #include <glib.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32 #ifndef _WIN32
  33 #include <sys/socket.h>
  34 #include <netinet/in.h>
  35 #include <arpa/inet.h>
  36 #include <netdb.h>
  37 #endif
  38 #include <errno.h>
  39
  40 #define LOG_PREFIX "scpi_tcp"
  41
  42 #define LENGTH_BYTES 4
  43
  44 struct scpi_tcp {
  45         char *address;
  46         char *port;
  47         int socket;
  48         char length_buf[LENGTH_BYTES];
  49         int length_bytes_read;
  50         int response_length;
  51         int response_bytes_read;
  52 };
  53
  54 SR_PRIV int scpi_tcp_open(void *priv)
  55 {
  56         struct scpi_tcp *tcp = priv;
  57         struct addrinfo hints;
  58         struct addrinfo *results, *res;
  59         int err;
  60
  61         memset(&hints, 0, sizeof(hints));
  62         hints.ai_family = AF_UNSPEC;
  63         hints.ai_socktype = SOCK_STREAM;
  64         hints.ai_protocol = IPPROTO_TCP;
  65
  66         err = getaddrinfo(tcp->address, tcp->port, &hints, &results);
  67
  68         if (err) {
  69                 sr_err("Address lookup failed: %s:%d: %s", tcp->address, tcp->port,
  70                         gai_strerror(err));
  71                 return SR_ERR;
  72         }
  73
  74         for (res = results; res; res = res->ai_next) {
  75                 if ((tcp->socket = socket(res->ai_family, res->ai_socktype,
  76                                                 res->ai_protocol)) < 0)
  77                         continue;
  78                 if (connect(tcp->socket, res->ai_addr, res->ai_addrlen) != 0) {
  79                         close(tcp->socket);
  80                         tcp->socket = -1;
  81                         continue;
  82                 }
  83                 break;
  84         }
  85
  86         freeaddrinfo(results);
  87
  88         if (tcp->socket < 0) {
  89                 sr_err("Failed to connect to %s:%s: %s", tcp->address, tcp->port,
  90                                 strerror(errno));
  91                 return SR_ERR;
  92         }
  93
  94         return SR_OK;
  95 }
  96
  97 SR_PRIV int scpi_tcp_source_add(void *priv, int events, int timeout,
  98                         sr_receive_data_callback_t cb, void *cb_data)
  99 {
 100         struct scpi_tcp *tcp = priv;
 101
 102         return sr_source_add(tcp->socket, events, timeout, cb, cb_data);
 103 }
 104
 105 SR_PRIV int scpi_tcp_source_remove(void *priv)
 106 {
 107         struct scpi_tcp *tcp = priv;
 108
 109         return sr_source_remove(tcp->socket);
 110 }
 111
 112 SR_PRIV int scpi_tcp_send(void *priv, const char *command)
 113 {
 114         struct scpi_tcp *tcp = priv;
 115         int len, out;
 116         char *terminated_command;
 117
 118         terminated_command = g_strdup_printf("%s\r\n", command);
 119         len = strlen(terminated_command);
 120         out = send(tcp->socket, terminated_command, len, 0);
 121         g_free(terminated_command);
 122
 123         if (out < 0) {
 124                 sr_err("Send error: %s", strerror(errno));
 125                 return SR_ERR;
 126         }
 127
 128         if (out < len) {
 129                 sr_dbg("Only sent %d/%d bytes of SCPI command: '%s'.", out,
 130                        len, command);
 131         }
 132
 133         sr_spew("Successfully sent SCPI command: '%s'.", command);
 134
 135         return SR_OK;
 136 }
 137
 138 SR_PRIV int scpi_tcp_read_begin(void *priv)
 139 {
 140         struct scpi_tcp *tcp = priv;
 141
 142         tcp->response_bytes_read = 0;
 143         tcp->length_bytes_read = 0;
 144
 145         return SR_OK;
 146 }
 147
 148 SR_PRIV int scpi_tcp_read_data(void *priv, char *buf, int maxlen)
 149 {
 150         struct scpi_tcp *tcp = priv;
 151         int len;
 152
 153         if (tcp->length_bytes_read < LENGTH_BYTES) {
 154                 len = recv(tcp->socket, tcp->length_buf + tcp->length_bytes_read,
 155                                 LENGTH_BYTES - tcp->length_bytes_read, 0);
 156                 if (len < 0) {
 157                         sr_err("Receive error: %s", strerror(errno));
 158                         return SR_ERR;
 159                 }
 160
 161                 tcp->length_bytes_read += len;
 162
 163                 if (tcp->length_bytes_read < LENGTH_BYTES)
 164                         return 0;
 165                 else
 166                         tcp->response_length = RL32(tcp->length_buf);
 167         }
 168
 169         if (tcp->response_bytes_read >= tcp->response_length)
 170                 return SR_ERR;
 171
 172         len = recv(tcp->socket, buf, maxlen, 0);
 173
 174         if (len < 0) {
 175                 sr_err("Receive error: %s", strerror(errno));
 176                 return SR_ERR;
 177         }
 178
 179         tcp->response_bytes_read += len;
 180
 181         return len;
 182 }
 183
 184 SR_PRIV int scpi_tcp_read_complete(void *priv)
 185 {
 186         struct scpi_tcp *tcp = priv;
 187
 188         return (tcp->length_bytes_read == LENGTH_BYTES &&
 189                         tcp->response_bytes_read >= tcp->response_length);
 190 }
 191
 192 SR_PRIV int scpi_tcp_close(void *priv)
 193 {
 194         struct scpi_tcp *tcp = priv;
 195
 196         if (close(tcp->socket) < 0)
 197                 return SR_ERR;
 198
 199         return SR_OK;
 200 }
 201
 202 SR_PRIV void scpi_tcp_free(void *priv)
 203 {
 204         struct scpi_tcp *tcp = priv;
 205
 206         g_free(tcp->address);
 207         g_free(tcp->port);
 208         g_free(tcp);
 209 }
 210
 211 SR_PRIV struct sr_scpi_dev_inst *scpi_tcp_dev_inst_new(const char *address,
 212                 const char *port)
 213 {
 214         struct sr_scpi_dev_inst *scpi;
 215         struct scpi_tcp *tcp;
 216
 217         scpi = g_malloc(sizeof(struct sr_scpi_dev_inst));
 218         tcp = g_malloc0(sizeof(struct scpi_tcp));
 219
 220         tcp->address = g_strdup(address);
 221         tcp->port = g_strdup(port);
 222         tcp->socket = -1;
 223
 224         scpi->open = scpi_tcp_open;
 225         scpi->source_add = scpi_tcp_source_add;
 226         scpi->source_remove = scpi_tcp_source_remove;
 227         scpi->send = scpi_tcp_send;
 228         scpi->read_begin = scpi_tcp_read_begin;
 229         scpi->read_data = scpi_tcp_read_data;
 230         scpi->read_complete = scpi_tcp_read_complete;
 231         scpi->close = scpi_tcp_close;
 232         scpi->free = scpi_tcp_free;
 233         scpi->priv = tcp;
 234
 235         return scpi;
 236 }