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 static int scpi_tcp_dev_inst_new(void *priv, const char *resource,
  55                 char **params, const char *serialcomm)
  56 {
  57         struct scpi_tcp *tcp = priv;
  58
  59         (void)resource;
  60         (void)serialcomm;
  61
  62         if (!params || !params[1] || !params[2]) {
  63                 sr_err("Invalid parameters.");
  64                 return SR_ERR;
  65         }
  66
  67         tcp->address = g_strdup(params[1]);
  68         tcp->port    = g_strdup(params[2]);
  69         tcp->socket  = -1;
  70
  71         return SR_OK;
  72 }
  73
  74 SR_PRIV int scpi_tcp_open(void *priv)
  75 {
  76         struct scpi_tcp *tcp = priv;
  77         struct addrinfo hints;
  78         struct addrinfo *results, *res;
  79         int err;
  80
  81         memset(&hints, 0, sizeof(hints));
  82         hints.ai_family = AF_UNSPEC;
  83         hints.ai_socktype = SOCK_STREAM;
  84         hints.ai_protocol = IPPROTO_TCP;
  85
  86         err = getaddrinfo(tcp->address, tcp->port, &hints, &results);
  87
  88         if (err) {
  89                 sr_err("Address lookup failed: %s:%d: %s", tcp->address, tcp->port,
  90                         gai_strerror(err));
  91                 return SR_ERR;
  92         }
  93
  94         for (res = results; res; res = res->ai_next) {
  95                 if ((tcp->socket = socket(res->ai_family, res->ai_socktype,
  96                                                 res->ai_protocol)) < 0)
  97                         continue;
  98                 if (connect(tcp->socket, res->ai_addr, res->ai_addrlen) != 0) {
  99                         close(tcp->socket);
 100                         tcp->socket = -1;
 101                         continue;
 102                 }
 103                 break;
 104         }
 105
 106         freeaddrinfo(results);
 107
 108         if (tcp->socket < 0) {
 109                 sr_err("Failed to connect to %s:%s: %s", tcp->address, tcp->port,
 110                                 strerror(errno));
 111                 return SR_ERR;
 112         }
 113
 114         return SR_OK;
 115 }
 116
 117 SR_PRIV int scpi_tcp_source_add(void *priv, int events, int timeout,
 118                         sr_receive_data_callback_t cb, void *cb_data)
 119 {
 120         struct scpi_tcp *tcp = priv;
 121
 122         return sr_source_add(tcp->socket, events, timeout, cb, cb_data);
 123 }
 124
 125 SR_PRIV int scpi_tcp_source_remove(void *priv)
 126 {
 127         struct scpi_tcp *tcp = priv;
 128
 129         return sr_source_remove(tcp->socket);
 130 }
 131
 132 SR_PRIV int scpi_tcp_send(void *priv, const char *command)
 133 {
 134         struct scpi_tcp *tcp = priv;
 135         int len, out;
 136         char *terminated_command;
 137
 138         terminated_command = g_strdup_printf("%s\r\n", command);
 139         len = strlen(terminated_command);
 140         out = send(tcp->socket, terminated_command, len, 0);
 141         g_free(terminated_command);
 142
 143         if (out < 0) {
 144                 sr_err("Send error: %s", strerror(errno));
 145                 return SR_ERR;
 146         }
 147
 148         if (out < len) {
 149                 sr_dbg("Only sent %d/%d bytes of SCPI command: '%s'.", out,
 150                        len, command);
 151         }
 152
 153         sr_spew("Successfully sent SCPI command: '%s'.", command);
 154
 155         return SR_OK;
 156 }
 157
 158 SR_PRIV int scpi_tcp_read_begin(void *priv)
 159 {
 160         struct scpi_tcp *tcp = priv;
 161
 162         tcp->response_bytes_read = 0;
 163         tcp->length_bytes_read = 0;
 164
 165         return SR_OK;
 166 }
 167
 168 SR_PRIV int scpi_tcp_read_data(void *priv, char *buf, int maxlen)
 169 {
 170         struct scpi_tcp *tcp = priv;
 171         int len;
 172
 173         if (tcp->length_bytes_read < LENGTH_BYTES) {
 174                 len = recv(tcp->socket, tcp->length_buf + tcp->length_bytes_read,
 175                                 LENGTH_BYTES - tcp->length_bytes_read, 0);
 176                 if (len < 0) {
 177                         sr_err("Receive error: %s", strerror(errno));
 178                         return SR_ERR;
 179                 }
 180
 181                 tcp->length_bytes_read += len;
 182
 183                 if (tcp->length_bytes_read < LENGTH_BYTES)
 184                         return 0;
 185                 else
 186                         tcp->response_length = RL32(tcp->length_buf);
 187         }
 188
 189         if (tcp->response_bytes_read >= tcp->response_length)
 190                 return SR_ERR;
 191
 192         len = recv(tcp->socket, buf, maxlen, 0);
 193
 194         if (len < 0) {
 195                 sr_err("Receive error: %s", strerror(errno));
 196                 return SR_ERR;
 197         }
 198
 199         tcp->response_bytes_read += len;
 200
 201         return len;
 202 }
 203
 204 SR_PRIV int scpi_tcp_read_complete(void *priv)
 205 {
 206         struct scpi_tcp *tcp = priv;
 207
 208         return (tcp->length_bytes_read == LENGTH_BYTES &&
 209                         tcp->response_bytes_read >= tcp->response_length);
 210 }
 211
 212 SR_PRIV int scpi_tcp_close(void *priv)
 213 {
 214         struct scpi_tcp *tcp = priv;
 215
 216         if (close(tcp->socket) < 0)
 217                 return SR_ERR;
 218
 219         return SR_OK;
 220 }
 221
 222 SR_PRIV void scpi_tcp_free(void *priv)
 223 {
 224         struct scpi_tcp *tcp = priv;
 225
 226         g_free(tcp->address);
 227         g_free(tcp->port);
 228 }
 229
 230 SR_PRIV const struct sr_scpi_dev_inst scpi_tcp_dev = {
 231         .name          = "TCP",
 232         .prefix        = "tcp",
 233         .priv_size     = sizeof(struct scpi_tcp),
 234         .dev_inst_new  = scpi_tcp_dev_inst_new,
 235         .open          = scpi_tcp_open,
 236         .source_add    = scpi_tcp_source_add,
 237         .source_remove = scpi_tcp_source_remove,
 238         .send          = scpi_tcp_send,
 239         .read_begin    = scpi_tcp_read_begin,
 240         .read_data     = scpi_tcp_read_data,
 241         .read_complete = scpi_tcp_read_complete,
 242         .close         = scpi_tcp_close,
 243         .free          = scpi_tcp_free,
 244 };