Jack2  1.9.11-RC1
JackPosixSemaphore.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 "JackPosixSemaphore.h"
21 #include "JackTools.h"
22 #include "JackConstants.h"
23 #include "JackError.h"
24 #include <fcntl.h>
25 #include <stdio.h>
26 #include <sys/time.h>
27 
28 namespace Jack
29 {
30 
31 void JackPosixSemaphore::BuildName(const char* client_name, const char* server_name, char* res, int size)
32 {
33  char ext_client_name[SYNC_MAX_NAME_SIZE + 1];
34  JackTools::RewriteName(client_name, ext_client_name);
35 #if __APPLE__ // POSIX semaphore names are limited to 32 characters...
36  snprintf(res, 32, "js_%s", ext_client_name);
37 #else
38  if (getenv("JACK_PROMISCUOUS_SERVER")) {
39  snprintf(res, size, "jack_sem.%s_%s", server_name, ext_client_name);
40  } else {
41  snprintf(res, size, "jack_sem.%d_%s_%s", JackTools::GetUID(), server_name, ext_client_name);
42  }
43 #endif
44 }
45 
46 bool JackPosixSemaphore::Signal()
47 {
48  int res;
49 
50  if (!fSemaphore) {
51  jack_error("JackPosixSemaphore::Signal name = %s already deallocated!!", fName);
52  return false;
53  }
54 
55  if (fFlush) {
56  return true;
57  }
58 
59  if ((res = sem_post(fSemaphore)) != 0) {
60  jack_error("JackPosixSemaphore::Signal name = %s err = %s", fName, strerror(errno));
61  }
62  return (res == 0);
63 }
64 
65 bool JackPosixSemaphore::SignalAll()
66 {
67  int res;
68 
69  if (!fSemaphore) {
70  jack_error("JackPosixSemaphore::SignalAll name = %s already deallocated!!", fName);
71  return false;
72  }
73 
74  if (fFlush) {
75  return true;
76  }
77 
78  if ((res = sem_post(fSemaphore)) != 0) {
79  jack_error("JackPosixSemaphore::SignalAll name = %s err = %s", fName, strerror(errno));
80  }
81  return (res == 0);
82 }
83 
84 bool JackPosixSemaphore::Wait()
85 {
86  int res;
87 
88  if (!fSemaphore) {
89  jack_error("JackPosixSemaphore::Wait name = %s already deallocated!!", fName);
90  return false;
91  }
92 
93  while ((res = sem_wait(fSemaphore) < 0)) {
94  jack_error("JackPosixSemaphore::Wait name = %s err = %s", fName, strerror(errno));
95  if (errno != EINTR) {
96  break;
97  }
98  }
99  return (res == 0);
100 }
101 
102 #if (_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) // glibc feature test
103 
104 bool JackPosixSemaphore::TimedWait(long usec)
105 {
106  int res;
107  struct timeval now;
108  timespec time;
109 
110  if (!fSemaphore) {
111  jack_error("JackPosixSemaphore::TimedWait name = %s already deallocated!!", fName);
112  return false;
113  }
114  gettimeofday(&now, 0);
115  time.tv_sec = now.tv_sec + usec / 1000000;
116  long tv_usec = (now.tv_usec + (usec % 1000000));
117  time.tv_sec += tv_usec / 1000000;
118  time.tv_nsec = (tv_usec % 1000000) * 1000;
119 
120  while ((res = sem_timedwait(fSemaphore, &time)) < 0) {
121  jack_error("JackPosixSemaphore::TimedWait err = %s", strerror(errno));
122  jack_log("JackPosixSemaphore::TimedWait now : %ld %ld ", now.tv_sec, now.tv_usec);
123  jack_log("JackPosixSemaphore::TimedWait next : %ld %ld ", time.tv_sec, time.tv_nsec/1000);
124  if (errno != EINTR) {
125  break;
126  }
127  }
128  return (res == 0);
129 }
130 
131 #else
132 #warning "JackPosixSemaphore::TimedWait is not supported: Jack in SYNC mode with JackPosixSemaphore will not run properly !!"
133 
134 bool JackPosixSemaphore::TimedWait(long usec)
135 {
136  return Wait();
137 }
138 #endif
139 
140 // Server side : publish the semaphore in the global namespace
141 bool JackPosixSemaphore::Allocate(const char* name, const char* server_name, int value)
142 {
143  BuildName(name, server_name, fName, sizeof(fName));
144  jack_log("JackPosixSemaphore::Allocate name = %s val = %ld", fName, value);
145 
146  if ((fSemaphore = sem_open(fName, O_CREAT | O_RDWR, 0777, value)) == (sem_t*)SEM_FAILED) {
147  jack_error("Allocate: can't check in named semaphore name = %s err = %s", fName, strerror(errno));
148  return false;
149  } else {
150  return true;
151  }
152 }
153 
154 // Client side : get the published semaphore from server
155 bool JackPosixSemaphore::ConnectInput(const char* name, const char* server_name)
156 {
157  BuildName(name, server_name, fName, sizeof(fName));
158  jack_log("JackPosixSemaphore::Connect name = %s", fName);
159 
160  // Temporary...
161  if (fSemaphore) {
162  jack_log("Already connected name = %s", name);
163  return true;
164  }
165 
166  if ((fSemaphore = sem_open(fName, O_RDWR)) == (sem_t*)SEM_FAILED) {
167  jack_error("Connect: can't connect named semaphore name = %s err = %s", fName, strerror(errno));
168  return false;
169  } else if (fSemaphore) {
170  int val = 0;
171  sem_getvalue(fSemaphore, &val);
172  jack_log("JackPosixSemaphore::Connect sem_getvalue %ld", val);
173  return true;
174  } else {
175  jack_error("Connect: fSemaphore not initialized!");
176  return false;
177  }
178 }
179 
180 bool JackPosixSemaphore::Connect(const char* name, const char* server_name)
181 {
182  return ConnectInput(name, server_name);
183 }
184 
185 bool JackPosixSemaphore::ConnectOutput(const char* name, const char* server_name)
186 {
187  return ConnectInput(name, server_name);
188 }
189 
190 bool JackPosixSemaphore::Disconnect()
191 {
192  if (fSemaphore) {
193  jack_log("JackPosixSemaphore::Disconnect name = %s", fName);
194  if (sem_close(fSemaphore) != 0) {
195  jack_error("Disconnect: can't disconnect named semaphore name = %s err = %s", fName, strerror(errno));
196  return false;
197  } else {
198  fSemaphore = NULL;
199  return true;
200  }
201  } else {
202  return true;
203  }
204 }
205 
206 // Server side : destroy the semaphore
207 void JackPosixSemaphore::Destroy()
208 {
209  if (fSemaphore != NULL) {
210  jack_log("JackPosixSemaphore::Destroy name = %s", fName);
211  sem_unlink(fName);
212  if (sem_close(fSemaphore) != 0) {
213  jack_error("Destroy: can't destroy semaphore name = %s err = %s", fName, strerror(errno));
214  }
215  fSemaphore = NULL;
216  } else {
217  jack_error("JackPosixSemaphore::Destroy semaphore == NULL");
218  }
219 }
220 
221 } // end of namespace
222 
SERVER_EXPORT void jack_error(const char *fmt,...)
Definition: JackError.cpp:92
SERVER_EXPORT void jack_log(const char *fmt,...)
Definition: JackError.cpp:108