libbase/sharedlib.cpp

   1 // sharedlib.cpp:  Shared Library support, for Gnash.
   2 //
   3 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Free Software
   4 //   Foundation, Inc
   5 //
   6 // This program is free software; you can redistribute it and/or modify
   7 // it under the terms of the GNU General Public License as published by
   8 // the Free Software Foundation; either version 3 of the License, or
   9 // (at your option) any later version.
  10 //
  11 // This program is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License
  17 // along with this program; if not, write to the Free Software
  18 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19 //
  20
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "gnashconfig.h"
  24 #endif
  25
  26 #include "log.h"
  27 #include "sharedlib.h"
  28
  29 #include <sys/stat.h>
  30 #include <unistd.h>
  31
  32 #include <string>
  33 #include <cstdlib>
  34
  35 #if defined(WIN32) || defined(_WIN32)
  36 # define LIBLTDL_DLL_IMPORT 1
  37 #endif
  38 #ifdef HAVE_DLFCN_H
  39 # include <dlfcn.h>
  40 #endif
  41 #ifdef HAVE_LIBGEN_H
  42 # include <libgen.h>
  43 #endif
  44
  45 #include "ltdl.h"
  46 #include <boost/thread/mutex.hpp>
  47
  48 #if defined(WIN32) || defined(_WIN32)
  49 int        lt_dlsetsearchpath   (const char *search_path);
  50 int        lt_dlinit           (void);
  51 void *     lt_dlsym            (lt_dlhandle handle, const char *name);
  52 const char *lt_dlerror         (void);
  53 int        lt_dlclose          (lt_dlhandle handle);
  54 int        lt_dlmakeresident   (lt_dlhandle handle);
  55 lt_dlhandle lt_dlopenext       (const char *filename);
  56 #endif
  57
  58 #if defined(_WIN32) || defined(WIN32)
  59 # define PLUGINSDIR "./"
  60 #endif
  61
  62 namespace gnash {
  63
  64 SharedLib::SharedLib(const std::string& filespec)
  65 {
  66     _filespec = filespec;
  67 }
  68
  69 SharedLib::SharedLib(const std::string& filespec, const std::string& envvar)
  70 {
  71     _filespec = filespec;
  72     scoped_lock lock(_libMutex);
  73
  74     // Initialize libtool's dynamic library loader
  75 #ifdef HAVE_LTDL
  76     int errors = lt_dlinit ();
  77     if (errors) {
  78         log_error (_("Couldn't initialize ltdl: %s"), lt_dlerror());
  79     }
  80 #else
  81 # warning "libltdl not enabled in build".
  82 #endif
  83     std::string pluginsdir;
  84     char *env = std::getenv (envvar.c_str());
  85     if (env) {
  86         pluginsdir = env;
  87     } else {
  88         pluginsdir = PLUGINSDIR;
  89     }
  90
  91 }
  92
  93 SharedLib::~SharedLib()
  94 {
  95 }
  96
  97 bool
  98 SharedLib::closeLib()
  99 {
 100 #ifdef HAVE_LTDL
 101     return lt_dlclose(_dlhandle);
 102 #else
 103     return true;
 104 #endif
 105 }
 106
 107 bool
 108 SharedLib::openLib()
 109 {
 110     return openLib(_filespec);
 111 }
 112
 113 bool
 114 SharedLib::openLib (const std::string& filespec)
 115 {
 116
 117     scoped_lock lock(_libMutex);
 118
 119     log_debug ("Trying to open shared library \"%s\"", filespec);
 120
 121 #ifdef HAVE_LTDL
 122     _dlhandle = lt_dlopenext (filespec.c_str());
 123
 124     if (_dlhandle == NULL) {
 125         log_error ("%s", lt_dlerror());
 126         return false;
 127     }
 128
 129     // Make this module unloadable
 130     lt_dlmakeresident(_dlhandle);
 131 #endif
 132
 133     log_debug (_("Opened dynamic library \"%s\""), filespec);
 134
 135     _filespec = filespec;
 136
 137     return true;
 138 }
 139
 140 SharedLib::initentry *
 141 SharedLib::getInitEntry (const std::string& symbol)
 142 {
 143     // GNASH_REPORT_FUNCTION;
 144     lt_ptr run = NULL;
 145
 146     scoped_lock lock(_libMutex);
 147
 148 #ifdef HAVE_LTDL
 149     run  = lt_dlsym (_dlhandle, symbol.c_str());
 150
 151     if (run == NULL) {
 152         log_error (_("Couldn't find symbol: %s"), symbol);
 153         return NULL;
 154     } else {
 155         log_debug (_("Found symbol %s @ %p"), symbol, (void *)run);
 156     }
 157 #else
 158     (void)symbol;
 159 #endif
 160
 161     return (initentry*)(run);
 162 }
 163
 164 SharedLib::entrypoint *
 165 SharedLib::getDllSymbol(const std::string& symbol)
 166 {
 167     GNASH_REPORT_FUNCTION;
 168
 169     lt_ptr run = NULL;
 170
 171     scoped_lock lock(_libMutex);
 172
 173 #ifdef HAVE_LTDL
 174     run  = lt_dlsym (_dlhandle, symbol.c_str());
 175 #endif
 176
 177     /*
 178     Realistically, we should never get a valid pointer with a value of 0
 179     Markus: 'Id est NULL.'
 180     */
 181     if (run == NULL) {
 182         log_error (_("Couldn't find symbol: %s"), symbol);
 183         return NULL;
 184     } else {
 185         log_debug (_("Found symbol %s @ %p"), symbol, (void *)run);
 186     }
 187
 188     return (entrypoint*)(run);
 189 }
 190
 191 } // end of gnash namespace