posix/JackFifo.cpp

   1 /*
   2 Copyright (C) 2004-2008 Grame
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU Lesser General Public License as published by
   6 the Free Software Foundation; either version 2.1 of the License, or
   7 (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU Lesser General Public License for more details.
  13
  14 You should have received a copy of the GNU Lesser General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17
  18 */
  19
  20 #include "JackFifo.h"
  21 #include "JackTools.h"
  22 #include "JackError.h"
  23 #include "JackPlatformPlug.h"
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <unistd.h>
  27 #include <fcntl.h>
  28 #include <stdio.h>
  29
  30 namespace Jack
  31 {
  32
  33 void JackFifo::BuildName(const char* client_name, const char* server_name, char* res)
  34 {
  35     char ext_client_name[JACK_CLIENT_NAME_SIZE + 1];
  36     JackTools::RewriteName(client_name, ext_client_name);
  37     sprintf(res, "%s/jack_fifo.%d_%s_%s", jack_client_dir, JackTools::GetUID(), server_name, ext_client_name);
  38 }
  39
  40 bool JackFifo::Signal()
  41 {
  42     bool res;
  43     char c = 0;
  44
  45     if (fFifo < 0) {
  46         jack_error("JackFifo::Signal name = %s already desallocated!!", fName);
  47         return false;
  48     }
  49
  50     if (fFlush)
  51         return true;
  52
  53     if ((res = (write(fFifo, &c, sizeof(c)) != sizeof(c)))) {
  54         jack_error("JackFifo::Signal name = %s err = %s", fName, strerror(errno));
  55     }
  56     return !res;
  57 }
  58
  59 bool JackFifo::SignalAll()
  60 {
  61     bool res;
  62     char c = 0;
  63
  64     if (fFifo < 0) {
  65         jack_error("JackFifo::SignalAll name = %s already desallocated!!", fName);
  66         return false;
  67     }
  68
  69     if (fFlush)
  70         return true;
  71
  72     if ((res = (write(fFifo, &c, sizeof(c)) != sizeof(c)))) {
  73         jack_error("JackFifo::SignalAll name = %s err = %s", fName, strerror(errno));
  74     }
  75     return !res;
  76 }
  77
  78 bool JackFifo::Wait()
  79 {
  80     bool res;
  81     char c;
  82
  83     if (fFifo < 0) {
  84         jack_error("JackFifo::Wait name = %s already desallocated!!", fName);
  85         return false;
  86     }
  87
  88     if ((res = (read(fFifo, &c, sizeof(c)) != sizeof(c)))) {
  89         jack_error("JackFifo::Wait name = %s err = %s", fName, strerror(errno));
  90     }
  91     return !res;
  92 }
  93
  94 #ifdef __APPLE__
  95 #warning JackFifo::TimedWait not available : synchronous mode may not work correctly if FIFO are used
  96 bool JackFifo::TimedWait(long usec)
  97 {
  98     return Wait();
  99 }
 100 #else
 101 // Does not work on OSX ??
 102 bool JackFifo::TimedWait(long usec)
 103 {
 104     int res;
 105
 106     if (fFifo < 0) {
 107         jack_error("JackFifo::TimedWait name = %s already desallocated!!", fName);
 108         return false;
 109     }
 110
 111     do {
 112         res = poll(&fPoll, 1, usec / 1000);
 113     } while (res < 0 && errno == EINTR);
 114
 115     if (fPoll.revents & POLLIN) {
 116         return Wait();
 117     } else {
 118         // Wait failure but we still continue...
 119         jack_log("JackFifo::TimedWait name = %s usec = %ld err = %s", fName, usec, strerror(errno));
 120         return true;
 121     }
 122 }
 123 #endif
 124
 125 // Server side
 126 bool JackFifo::Allocate(const char* name, const char* server_name, int value)
 127 {
 128     struct stat statbuf;
 129     BuildName(name, server_name, fName);
 130     jack_log("JackFifo::Allocate name = %s", fName);
 131
 132     if (stat(fName, &statbuf) < 0) {
 133         if (errno == ENOENT || errno == EPERM) {
 134             if (mkfifo(fName, 0666) < 0) {
 135                 jack_error("Cannot create inter-client FIFO name = %s err = %s", name, strerror(errno));
 136                 return false;
 137             }
 138         } else {
 139             jack_error("Cannot check on FIFO %s", name);
 140             return false;
 141         }
 142     } else {
 143         if (!S_ISFIFO(statbuf.st_mode)) {
 144             jack_error("FIFO name = %s already exists, but is not a FIFO", name);
 145             return false;
 146         }
 147     }
 148
 149     if ((fFifo = open(fName, O_RDWR | O_CREAT, 0666)) < 0) {
 150         jack_error("Cannot open FIFO name = %s err = %s", name, strerror(errno));
 151         return false;
 152     } else {
 153         fPoll.fd = fFifo;
 154         fPoll.events = POLLERR | POLLIN | POLLHUP | POLLNVAL;
 155         return true;
 156     }
 157 }
 158
 159 // Client side
 160 bool JackFifo::ConnectAux(const char* name, const char* server_name, int access)
 161 {
 162     BuildName(name, server_name, fName);
 163     jack_log("JackFifo::ConnectAux name = %s", fName);
 164
 165     // Temporary...
 166     if (fFifo >= 0) {
 167         jack_log("Already connected name = %s", name);
 168         return true;
 169     }
 170
 171     if ((fFifo = open(fName, access)) < 0) {
 172         jack_error("Connect: can't connect named fifo name = %s err = %s", fName, strerror(errno));
 173         return false;
 174     } else {
 175         fPoll.fd = fFifo;
 176         fPoll.events = POLLERR | POLLIN | POLLHUP | POLLNVAL;
 177         return true;
 178     }
 179 }
 180
 181 bool JackFifo::Connect(const char* name, const char* server_name)
 182 {
 183     return ConnectAux(name, server_name, O_RDWR);
 184 }
 185
 186 bool JackFifo::ConnectOutput(const char* name, const char* server_name)
 187 {
 188     return ConnectAux(name, server_name, O_WRONLY | O_NONBLOCK);
 189 }
 190
 191 bool JackFifo::ConnectInput(const char* name, const char* server_name)
 192 {
 193     return ConnectAux(name, server_name, O_RDONLY);
 194 }
 195
 196 bool JackFifo::Disconnect()
 197 {
 198     if (fFifo >= 0) {
 199         jack_log("JackFifo::Disconnect %s", fName);
 200         if (close(fFifo) != 0) {
 201             jack_error("Disconnect: can't disconnect named fifo name = %s err = %s", fName, strerror(errno));
 202             return false;
 203         } else {
 204             fFifo = -1;
 205             return true;
 206         }
 207     } else {
 208         return true;
 209     }
 210 }
 211
 212 // Server side : destroy the fifo
 213 void JackFifo::Destroy()
 214 {
 215     if (fFifo > 0) {
 216         jack_log("JackFifo::Destroy name = %s", fName);
 217         unlink(fName);
 218         if (close(fFifo) != 0) {
 219             jack_error("Destroy: can't destroy fifo name = %s err = %s", fName, strerror(errno));
 220         }
 221         fFifo = -1;
 222     } else {
 223         jack_error("JackFifo::Destroy fifo < 0");
 224     }
 225 }
 226
 227 } // end of namespace
 228