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 #include "libsigrok.h"
  21 #include "libsigrok-internal.h"
  22
  23 #include <glib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include <sys/socket.h>
  27 #include <netinet/in.h>
  28 #include <arpa/inet.h>
  29 #include <netdb.h>
  30 #include <errno.h>
  31
  32 /* Message logging helpers with subsystem-specific prefix string. */
  33 #define LOG_PREFIX "scpi_tcp: "
  34 #define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
  35 #define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
  36 #define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
  37 #define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
  38 #define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
  39
  40 struct scpi_tcp {
  41         char *address;
  42         char *port;
  43         int socket;
  44 };
  45
  46 SR_PRIV int scpi_tcp_open(void *priv)
  47 {
  48         struct scpi_tcp *tcp = priv;
  49         struct addrinfo hints;
  50         struct addrinfo *results, *res;
  51         int err;
  52
  53         memset(&hints, 0, sizeof(hints));
  54         hints.ai_family = AF_UNSPEC;
  55         hints.ai_socktype = SOCK_STREAM;
  56         hints.ai_protocol = IPPROTO_TCP;
  57
  58         err = getaddrinfo(tcp->address, tcp->port, &hints, &results);
  59
  60         if (err) {
  61                 sr_err("Address lookup failed: %s:%d: %s", tcp->address, tcp->port,
  62                         gai_strerror(err));
  63                 return SR_ERR;
  64         }
  65
  66         for (res = results; res; res = res->ai_next) {
  67                 if ((tcp->socket = socket(res->ai_family, res->ai_socktype,
  68                                                 res->ai_protocol)) < 0)
  69                         continue;
  70                 if (connect(tcp->socket, res->ai_addr, res->ai_addrlen) != 0) {
  71                         close(tcp->socket);
  72                         tcp->socket = -1;
  73                         continue;
  74                 }
  75                 break;
  76         }
  77
  78         freeaddrinfo(results);
  79
  80         if (tcp->socket < 0) {
  81                 sr_err("Failed to connect to %s:%s: %s", tcp->address, tcp->port,
  82                                 strerror(errno));
  83                 return SR_ERR;
  84         }
  85
  86         return SR_OK;
  87 }
  88
  89 SR_PRIV int scpi_tcp_source_add(void *priv, int events, int timeout,
  90                         sr_receive_data_callback_t cb, void *cb_data)
  91 {
  92         struct scpi_tcp *tcp = priv;
  93
  94         return sr_source_add(tcp->socket, events, timeout, cb, cb_data);
  95 }
  96
  97 SR_PRIV int scpi_tcp_source_remove(void *priv)
  98 {
  99         struct scpi_tcp *tcp = priv;
 100
 101         return sr_source_remove(tcp->socket);
 102 }
 103
 104 SR_PRIV int scpi_tcp_send(void *priv, const char *command)
 105 {
 106         struct scpi_tcp *tcp = priv;
 107         int len, out;
 108         char *terminated_command;
 109
 110         terminated_command = g_strdup_printf("%s\r\n", command);
 111         len = strlen(terminated_command);
 112         out = send(tcp->socket, terminated_command, len, 0);
 113         g_free(terminated_command);
 114
 115         if (out < 0) {
 116                 sr_err("Send error: %s", strerror(errno));
 117                 return SR_ERR;
 118         }
 119
 120         if (out < len) {
 121                 sr_dbg("Only sent %d/%d bytes of SCPI command: '%s'.", out,
 122                        len, command);
 123         }
 124
 125         sr_spew("Successfully sent SCPI command: '%s'.", command);
 126
 127         return SR_OK;
 128 }
 129
 130 SR_PRIV int scpi_tcp_receive(void *priv, char **scpi_response)
 131 {
 132         struct scpi_tcp *tcp = priv;
 133         GString *response;
 134         char buf[256];
 135         int len;
 136
 137         response = g_string_sized_new(1024);
 138
 139         len = recv(tcp->socket, buf, sizeof(buf), 0);
 140
 141         if (len < 0) {
 142                 sr_err("Receive error: %s", strerror(errno));
 143                 g_string_free(response, TRUE);
 144                 return SR_ERR;
 145         }
 146
 147         response = g_string_append_len(response, buf + 4, len - 4);
 148
 149         *scpi_response = response->str;
 150
 151         sr_dbg("SCPI response received (length %d): '%.50s'",
 152                response->len, response->str);
 153
 154         g_string_free(response, FALSE);
 155
 156         return SR_OK;
 157 }
 158
 159 SR_PRIV int scpi_tcp_read(void *priv, char *buf, int maxlen)
 160 {
 161         struct scpi_tcp *tcp = priv;
 162         int len;
 163
 164         len = recv(tcp->socket, buf, maxlen, 0);
 165
 166         if (len < 0) {
 167                 sr_err("Receive error: %s", strerror(errno));
 168                 return SR_ERR;
 169         }
 170
 171         return len;
 172 }
 173
 174 SR_PRIV int scpi_tcp_close(void *priv)
 175 {
 176         struct scpi_tcp *tcp = priv;
 177
 178         if (close(tcp->socket) < 0)
 179                 return SR_ERR;
 180
 181         return SR_OK;
 182 }
 183
 184 SR_PRIV void scpi_tcp_free(void *priv)
 185 {
 186         struct scpi_tcp *tcp = priv;
 187
 188         g_free(tcp->address);
 189         g_free(tcp->port);
 190         g_free(tcp);
 191 }
 192
 193 SR_PRIV struct sr_scpi_dev_inst *scpi_tcp_dev_inst_new(const char *address,
 194                 const char *port)
 195 {
 196         struct sr_scpi_dev_inst *scpi;
 197         struct scpi_tcp *tcp;
 198
 199         scpi = g_malloc(sizeof(struct sr_scpi_dev_inst));
 200         tcp = g_malloc0(sizeof(struct scpi_tcp));
 201
 202         tcp->address = g_strdup(address);
 203         tcp->port = g_strdup(port);
 204         tcp->socket = -1;
 205
 206         scpi->open = scpi_tcp_open;
 207         scpi->source_add = scpi_tcp_source_add;
 208         scpi->source_remove = scpi_tcp_source_remove;
 209         scpi->send = scpi_tcp_send;
 210         scpi->receive = scpi_tcp_receive;
 211         scpi->read = scpi_tcp_read;
 212         scpi->close = scpi_tcp_close;
 213         scpi->free = scpi_tcp_free;
 214         scpi->priv = tcp;
 215
 216         return scpi;
 217 }