common/JackShmMem.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 "JackError.h"
  21 #include "JackShmMem.h"
  22 #include <stdio.h>
  23
  24 namespace Jack
  25 {
  26
  27 static unsigned int fSegmentNum = 0;
  28 static jack_shm_info_t gInfo;
  29
  30 JackShmMem::JackShmMem()
  31 {
  32     JackShmMemAble::Init();
  33     LockMemory();
  34 }
  35
  36 JackShmMem::~JackShmMem()
  37 {
  38     UnlockMemory();
  39 }
  40
  41 void JackShmMemAble::Init()
  42 {
  43     fInfo.index = gInfo.index;
  44     fInfo.ptr.attached_at = gInfo.ptr.attached_at;
  45     fInfo.size = gInfo.size;
  46 }
  47
  48 void* JackShmMem::operator new(size_t size, void* memory)
  49 {
  50     jack_log("JackShmMem::new placement size = %ld", size);
  51     return memory;
  52 }
  53
  54 void* JackShmMem::operator new(size_t size)
  55 {
  56     jack_shm_info_t info;
  57     JackShmMem* obj;
  58     char name[64];
  59
  60     snprintf(name, sizeof(name), "/jack_shared%d", fSegmentNum++);
  61
  62     if (jack_shmalloc(name, size, &info)) {
  63         jack_error("Cannot create shared memory segment of size = %d", size, strerror(errno));
  64         goto error;
  65     }
  66
  67     if (jack_attach_shm(&info)) {
  68         jack_error("Cannot attach shared memory segment name = %s err = %s", name, strerror(errno));
  69         jack_destroy_shm(&info);
  70         goto error;
  71     }
  72
  73     obj = (JackShmMem*)jack_shm_addr(&info);
  74     // It is unsafe to set object fields directly (may be overwritten during object initialization),
  75     // so use an intermediate global data
  76     gInfo.index = info.index;
  77     gInfo.size = size;
  78     gInfo.ptr.attached_at = info.ptr.attached_at;
  79
  80     jack_log("JackShmMem::new index = %ld attached = %x size = %ld ", info.index, info.ptr.attached_at, size);
  81     return obj;
  82
  83 error:
  84     jack_error("JackShmMem::new bad alloc", size);
  85     throw std::bad_alloc();
  86 }
  87
  88 void JackShmMem::operator delete(void* p, size_t size)
  89 {
  90     jack_shm_info_t info;
  91     JackShmMem* obj = (JackShmMem*)p;
  92     info.index = obj->fInfo.index;
  93     info.ptr.attached_at = obj->fInfo.ptr.attached_at;
  94
  95     jack_log("JackShmMem::delete size = %ld index = %ld", size, info.index);
  96
  97     jack_release_shm(&info);
  98     jack_destroy_shm(&info);
  99 }
 100
 101 void JackShmMem::operator delete(void* obj)
 102 {
 103     if (obj) {
 104         JackShmMem::operator delete(obj, 0);
 105     }
 106 }
 107
 108 void LockMemoryImp(void* ptr, size_t size)
 109 {
 110     if (CHECK_MLOCK((char*)ptr, size)) {
 111         jack_log("Succeeded in locking %u byte memory area", size);
 112     } else {
 113         jack_error("Cannot lock down %u byte memory area (%s)", size, strerror(errno));
 114     }
 115 }
 116
 117 void InitLockMemoryImp(void* ptr, size_t size)
 118 {
 119     if (CHECK_MLOCK((char*)ptr, size)) {
 120         memset(ptr, 0, size);
 121         jack_log("Succeeded in locking %u byte memory area", size);
 122     } else {
 123         jack_error("Cannot lock down %u byte memory area (%s)", size, strerror(errno));
 124     }
 125 }
 126
 127 void UnlockMemoryImp(void* ptr, size_t size)
 128 {
 129     if (CHECK_MUNLOCK((char*)ptr, size)) {
 130         jack_log("Succeeded in unlocking %u byte memory area", size);
 131     } else {
 132         jack_error("Cannot unlock down %u byte memory area (%s)", size, strerror(errno));
 133     }
 134 }
 135
 136 void LockAllMemory()
 137 {
 138     if (CHECK_MLOCKALL()) {
 139         jack_log("Succeeded in locking all memory");
 140     } else {
 141         jack_error("Cannot lock all memory (%s)", strerror(errno));
 142     }
 143 }
 144
 145 void UnlockAllMemory()
 146 {
 147     if (CHECK_MUNLOCKALL()) {
 148         jack_log("Succeeded in unlocking all memory");
 149     } else {
 150         jack_error("Cannot unlock all memory (%s)", strerror(errno));
 151     }
 152 }
 153
 154
 155 } // end of namespace
 156