mdw@git.distorted.org.uk Git - jog/blob - tx-socket.c

   1 /* -*-c-*-
   2  *
   3  * $Id: tx-socket.c,v 1.2 2002/01/30 09:25:35 mdw Exp $
   4  *
   5  * Socket transport
   6  *
   7  * (c) 2001 Mark Wooding
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Jog: Programming for a jogging machine.
  13  *
  14  * Jog is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * Jog is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Jog; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Header files ------------------------------------------------------*/
  30
  31 #ifdef HAVE_CONFIG_H
  32 #  include "config.h"
  33 #endif
  34
  35 #include <errno.h>
  36 #include <stddef.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40
  41 #include <sys/types.h>
  42 #include <unistd.h>
  43 #include <sys/socket.h>
  44 #include <sys/un.h>
  45 #include <pthread.h>
  46
  47 #include <mLib/alloc.h>
  48 #include <mLib/darray.h>
  49 #include <mLib/sub.h>
  50
  51 #include "err.h"
  52 #include "txport.h"
  53 #include "tx-socket.h"
  54
  55 #undef sun
  56
  57 /*----- Data structures ---------------------------------------------------*/
  58
  59 typedef struct txsock {
  60   txport tx;                            /* Transport base */
  61   int fd;                               /* File descriptor */
  62 } txsock;
  63
  64 /*----- Main code ---------------------------------------------------------*/
  65
  66 /* --- @txsock_create@ --- *
  67  *
  68  * Arguments:   @const char *file@ = filename for socket
  69  *
  70  * Returns:     Pointer to created transport block.
  71  *
  72  * Use:         Creates a socket transport.
  73  */
  74
  75 txport *txsock_create(const char *file)
  76 {
  77   txsock *tx;
  78   int fd;
  79   struct sockaddr_un *sun;
  80   size_t len, sunsz;
  81
  82   /* --- Set up the address block --- */
  83
  84   len = strlen(file) + 1;
  85   sunsz = offsetof(struct sockaddr_un, sun_path) + len;
  86   sun = xmalloc(sunsz);
  87   sun->sun_family = AF_UNIX;
  88   memcpy(sun->sun_path, file, len);
  89
  90   /* --- Create the socket --- */
  91
  92   if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
  93     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
  94                "error creating socket: %s", strerror(errno));
  95     goto fail_0;
  96   }
  97
  98   /* --- Connect --- */
  99
 100   if (connect(fd, (struct sockaddr *)sun, sunsz)) {
 101     err_report(ERR_TXPORT, ERRTX_CREATE, errno,
 102                "couldn't connect to `%s': %s", file, strerror(errno));
 103     goto fail_1;
 104   }
 105
 106   /* --- Done --- */
 107
 108   tx = CREATE(txsock);
 109   tx->fd = fd;
 110   xfree(sun);
 111   return (&tx->tx);
 112
 113   /* --- Tidy up because it all went horribly wrong --- */
 114
 115 fail_1:
 116   close(fd);
 117 fail_0:
 118   xfree(sun);
 119   return (0);
 120 }
 121
 122 /* --- @txsock_write@ --- *
 123  *
 124  * Arguments:   @txport *txg@ = pointer to transport context
 125  *              @const void *p@ = pointer to buffer
 126  *              @size_t sz@ = size of the buffer
 127  *
 128  * Returns:     Number of bytes written, or @-1@ on error.
 129  *
 130  * Use:         Writes data to a transport.
 131  */
 132
 133 ssize_t txsock_write(txport *txg, const void *p, size_t sz)
 134 {
 135   txsock *tx = (txsock *)txg;
 136
 137   return (write(tx->fd, p, sz));
 138 }
 139
 140 /* --- @txsock_fetch@ --- *
 141  *
 142  * Arguments:   @void *txv@ = pointer to transport context
 143  *
 144  * Returns:     Nothing of interest.
 145  *
 146  * Use:         Thread to fetch data from a socket.
 147  */
 148
 149 void *txsock_fetch(void *txv)
 150 {
 151   txsock *tx = txv;
 152   unsigned char buf[BUFSIZ];
 153   ssize_t n;
 154   int e;
 155
 156   /* --- Read data while it arrives --- */
 157
 158   for (;;) {
 159     n = read(tx->fd, buf, sizeof(buf));
 160     if (n < 0) {
 161       err_report(ERR_TXPORT, ERRTX_READ, errno,
 162                  "error reading from socket: %s", strerror(errno));
 163       break;
 164     }
 165     if (!n)
 166       break;
 167     if ((e = pthread_mutex_lock(&tx->tx.mx)) != 0) {
 168       err_report(ERR_TXPORT, ERRTX_READ, e,
 169                  "error locking mutex: %s", strerror(e));
 170       break;
 171     }
 172     DA_ENSURE(&tx->tx.buf, n);
 173     memcpy(DA(&tx->tx.buf) + DA_LEN(&tx->tx.buf), buf, n);
 174     DA_EXTEND(&tx->tx.buf, n);
 175     pthread_cond_signal(&tx->tx.cv);
 176     pthread_mutex_unlock(&tx->tx.mx);
 177   }
 178
 179   /* --- Deal with crapness --- */
 180
 181   e = pthread_mutex_lock(&tx->tx.mx);
 182   tx->tx.s = TX_CLOSE;
 183   pthread_cond_signal(&tx->tx.cv);
 184   pthread_mutex_unlock(&tx->tx.mx);
 185   return (0);
 186 }
 187
 188 /* --- @txsock_destroy@ --- *
 189  *
 190  * Arguments:   @txport *txg@ = pointer to transport context
 191  *
 192  * Returns:     ---
 193  *
 194  * Use:         Destroys a socket transport.
 195  */
 196
 197 void txsock_destroy(txport *txg)
 198 {
 199   txsock *tx = (txsock *)txg;
 200
 201   close(tx->fd);
 202   DESTROY(tx);
 203 }
 204
 205 /*----- That's all, folks -------------------------------------------------*/