code.delx.au - pulseaudio/blob - src/pulsecore/pipe.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2006-2007 Pierre Ossman <ossman@cendio.se> for Cendio AB
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2.1 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <errno.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29
  30 #include <sys/types.h>
  31
  32 #include <pulsecore/socket.h>
  33
  34 #include "pipe.h"
  35
  36 #ifndef HAVE_PIPE
  37
  38 static int set_block(int fd, int blocking) {
  39 #ifdef O_NONBLOCK
  40
  41     int v;
  42
  43     assert(fd >= 0);
  44
  45     if ((v = fcntl(fd, F_GETFL)) < 0)
  46         return -1;
  47
  48     if (blocking)
  49         v &= ~O_NONBLOCK;
  50     else
  51         v |= O_NONBLOCK;
  52
  53     if (fcntl(fd, F_SETFL, v) < 0)
  54         return -1;
  55
  56     return 0;
  57
  58 #elif defined(OS_IS_WIN32)
  59
  60     u_long arg;
  61
  62     arg = !blocking;
  63
  64     if (ioctlsocket(fd, FIONBIO, &arg) < 0)
  65         return -1;
  66
  67     return 0;
  68
  69 #else
  70
  71     return -1;
  72
  73 #endif
  74 }
  75
  76 int pipe(int filedes[2]) {
  77     int listener;
  78     struct sockaddr_in addr, peer;
  79     socklen_t len;
  80
  81     listener = -1;
  82     filedes[0] = -1;
  83     filedes[1] = -1;
  84
  85     listener = socket(PF_INET, SOCK_STREAM, 0);
  86     if (listener < 0)
  87         goto error;
  88
  89     filedes[0] = socket(PF_INET, SOCK_STREAM, 0);
  90     if (filedes[0] < 0)
  91         goto error;
  92
  93     filedes[1] = socket(PF_INET, SOCK_STREAM, 0);
  94     if (filedes[1] < 0)
  95         goto error;
  96
  97     /* Make non-blocking so that connect() won't block */
  98     if (set_block(filedes[0], 0) < 0)
  99         goto error;
 100
 101     addr.sin_family = AF_INET;
 102     addr.sin_port = 0;
 103     addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 104
 105     if (bind(listener, (struct sockaddr*)&addr, sizeof(addr)) < 0)
 106         goto error;
 107
 108     if (listen(listener, 1) < 0)
 109         goto error;
 110
 111     len = sizeof(addr);
 112     if (getsockname(listener, (struct sockaddr*)&addr, &len) < 0)
 113         goto error;
 114
 115     if (connect(filedes[0], (struct sockaddr*)&addr, sizeof(addr)) < 0) {
 116 #ifdef OS_IS_WIN32
 117         if (WSAGetLastError() != EWOULDBLOCK)
 118 #else
 119         if (errno != EINPROGRESS)
 120 #endif
 121             goto error;
 122     }
 123
 124     len = sizeof(peer);
 125     filedes[1] = accept(listener, (struct sockaddr*)&peer, &len);
 126     if (filedes[1] < 0)
 127         goto error;
 128
 129     /* Restore blocking */
 130     if (set_block(filedes[0], 1) < 0)
 131         goto error;
 132
 133     len = sizeof(addr);
 134     if (getsockname(filedes[0], (struct sockaddr*)&addr, &len) < 0)
 135         goto error;
 136
 137     /* Check that someone else didn't steal the connection */
 138     if ((addr.sin_port != peer.sin_port) || (addr.sin_addr.s_addr != peer.sin_addr.s_addr))
 139         goto error;
 140
 141     pa_close(listener);
 142
 143     return 0;
 144
 145 error:
 146         if (listener >= 0)
 147                 pa_close(listener);
 148         if (filedes[0] >= 0)
 149                 pa_close(filedes[0]);
 150         if (filedes[1] >= 0)
 151                 pa_close(filedes[0]);
 152
 153         return -1;
 154 }
 155
 156 #endif /* HAVE_PIPE */