1 thilo.boehm 1.1 //%LICENSE////////////////////////////////////////////////////////////////
  2                 //
  3                 // Licensed to The Open Group (TOG) under one or more contributor license
  4                 // agreements.  Refer to the OpenPegasusNOTICE.txt file distributed with
  5                 // this work for additional information regarding copyright ownership.
  6                 // Each contributor licenses this file to you under the OpenPegasus Open
  7                 // Source License; you may not use this file except in compliance with the
  8                 // License.
  9                 //
 10                 // Permission is hereby granted, free of charge, to any person obtaining a
 11                 // copy of this software and associated documentation files (the "Software"),
 12                 // to deal in the Software without restriction, including without limitation
 13                 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
 14                 // and/or sell copies of the Software, and to permit persons to whom the
 15                 // Software is furnished to do so, subject to the following conditions:
 16                 //
 17                 // The above copyright notice and this permission notice shall be included
 18                 // in all copies or substantial portions of the Software.
 19                 //
 20                 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 21                 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 22 thilo.boehm 1.1 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 23                 // IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 24                 // CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 25                 // TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 26                 // SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 27                 //
 28                 //////////////////////////////////////////////////////////////////////////
 29                 //
 30                 //%/////////////////////////////////////////////////////////////////////////////
 31                 
 32                 #include <Pegasus/Common/PegasusAssert.h>
 33                 #include "DynamicLibrary.h"
 34                 
 35                 #if defined(PEGASUS_OS_TYPE_WINDOWS)
 36                 # include "DynamicLibraryWindows.cpp"
 37                 #elif defined(PEGASUS_OS_TYPE_UNIX) || defined(PEGASUS_OS_VMS)
 38                 # include "DynamicLibraryPOSIX.cpp"
 39                 #else
 40                 # error "Unsupported platform"
 41                 #endif
 42                 
 43 thilo.boehm 1.1 PEGASUS_NAMESPACE_BEGIN
 44                 
 45                 DynamicLibrary::DynamicLibrary()
 46                     : _handle(0),
 47                       _referenceCount(0)
 48                 {
 49                 }
 50                 
 51                 DynamicLibrary::DynamicLibrary(const DynamicLibrary& library)
 52                     : _fileName(library._fileName),
 53                       _handle(0),
 54                       _referenceCount(0)
 55                 {
 56                     // load the module again, if necessary. this effectively increments the
 57                     // operating system's reference count for the module.
 58                     if (library.isLoaded())
 59                     {
 60                         if (load())
 61                         {
 62                             _referenceCount = library._referenceCount;
 63                         }
 64 thilo.boehm 1.1     }
 65                 }
 66                 
 67                 DynamicLibrary::DynamicLibrary(const String& fileName)
 68                     : _fileName(fileName),
 69                       _handle(0),
 70                       _referenceCount(0)
 71                 {
 72                 }
 73                 
 74                 DynamicLibrary::~DynamicLibrary()
 75                 {
 76                     // Unload the module, if necessary, to keep the operating system's
 77                     // reference count accurate.  One call to _unload() takes care of it
 78                     // no matter how high _referenceCount is.
 79                 
 80                     if (_referenceCount > 0)
 81                     {
 82                         PEGASUS_ASSERT(_handle != 0);
 83                         _unload();
 84                     }
 85 thilo.boehm 1.1 }
 86                 
 87                 DynamicLibrary& DynamicLibrary::operator=(const DynamicLibrary& library)
 88                 {
 89                     if (this == &library)
 90                     {
 91                         return *this;
 92                     }
 93                 
 94                     while (isLoaded())
 95                     {
 96                         unload();
 97                     }
 98                 
 99                     _fileName = library._fileName;
100                 
101                     // load the module again, if necessary. this effectively increments the
102                     // operating system's reference count for the module.
103                     if (library.isLoaded())
104                     {
105                         if (load())
106 thilo.boehm 1.1         {
107                             _referenceCount = library._referenceCount;
108                         }
109                     }
110                 
111                     return *this;
112                 }
113                 
114                 Boolean DynamicLibrary::isLoaded() const
115                 {
116                     return _handle != 0;
117                 }
118                 
119                 Boolean DynamicLibrary::load()
120                 {
121                     AutoMutex lock(_loadMutex);
122                 
123                     Boolean loaded = true;
124                 
125                     if (_referenceCount == 0)
126                     {
127 thilo.boehm 1.1         PEGASUS_ASSERT(_handle == 0);
128                         loaded = _load();
129                     }
130                 
131                     if (loaded)
132                     {
133                         PEGASUS_ASSERT(_handle != 0);
134                         _referenceCount++;
135                     }
136                 
137                     return loaded;
138                 }
139                 
140                 const String& DynamicLibrary::getLoadErrorMessage() const
141                 {
142                     return _loadErrorMessage;
143                 }
144                 
145                 void DynamicLibrary::unload()
146                 {
147                     AutoMutex lock(_loadMutex);
148 thilo.boehm 1.1 
149                     PEGASUS_ASSERT(_referenceCount > 0);
150                     PEGASUS_ASSERT(_handle != 0);
151                 
152                     _referenceCount--;
153                 
154                     if (_referenceCount == 0)
155                     {
156                         _unload();
157                         _handle = 0;
158                         _loadErrorMessage.clear();
159                     }
160                 }
161                 
162                 const String& DynamicLibrary::getFileName() const
163                 {
164                     return _fileName;
165                 }
166                 
167                 PEGASUS_NAMESPACE_END