src/SDL_loadso.c
author Sam Lantinga <slouken@libsdl.org>
Wed, 06 Mar 2002 05:20:11 +0000
changeset 294 d2d48e10f370
child 296 fab1ddc4d7bf
permissions -rw-r--r--
Added a new header file: SDL_loadso.h
It contains the following functions:
SDL_LoadObject(), SDL_LoadFunction(), SDL_UnloadObject()
The UNIX esd and arts audio code use these to dynamically load
their respective audio libraries.
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
     4 
     5     This library is free software; you can redistribute it and/or
     6     modify it under the terms of the GNU Library General Public
     7     License as published by the Free Software Foundation; either
     8     version 2 of the License, or (at your option) any later version.
     9 
    10     This library is distributed in the hope that it will be useful,
    11     but WITHOUT ANY WARRANTY; without even the implied warranty of
    12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    13     Library General Public License for more details.
    14 
    15     You should have received a copy of the GNU Library General Public
    16     License along with this library; if not, write to the Free
    17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    18 
    19     Sam Lantinga
    20     slouken@libsdl.org
    21 */
    22 
    23 #ifdef SAVE_RCSID
    24 static char rcsid =
    25  "@(#) $Id$";
    26 #endif
    27 
    28 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
    29 /* System dependent library loading routines                           */
    30 
    31 #include <stdio.h>
    32 #if defined(USE_DLOPEN)
    33 # include <dlfcn.h>
    34 #elif defined(WIN32)
    35 # include <windows.h>
    36 #elif defined(__BEOS__)
    37 # include <be/kernel/image.h>
    38 #elif defined(macintosh)
    39 # include <string.h>
    40 # include <Strings.h>
    41 # include <CodeFragments.h>
    42 # include <Errors.h>
    43 #else
    44 /*#error Unsupported dynamic link environment*/
    45 #endif /* system type */
    46 
    47 #include "SDL_error.h"
    48 #include "SDL_loadso.h"
    49 
    50 void *SDL_LoadObject(const char *sofile)
    51 {
    52 	void *handle = NULL;
    53 	const char *loaderror = "SDL_LoadObject() not implemented";
    54 #if defined(USE_DLOPEN)
    55 /* * */
    56 	handle = dlopen(sofile, RTLD_NOW);
    57 	loaderror = (char *)dlerror();
    58 #elif defined(WIN32)
    59 /* * */
    60 	char errbuf[512];
    61 
    62 	handle = (void *)LoadLibrary(sofile);
    63 
    64 	/* Generate an error message if all loads failed */
    65 	if ( handle == NULL ) {
    66 		FormatMessage((FORMAT_MESSAGE_IGNORE_INSERTS |
    67 					FORMAT_MESSAGE_FROM_SYSTEM),
    68 				NULL, GetLastError(), 
    69 				MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
    70 				errbuf, SDL_TABLESIZE(errbuf), NULL);
    71 		loaderror = errbuf;
    72 	}
    73 #elif defined(__BEOS__)
    74 /* * */
    75 	image_id library_id;
    76 
    77 	library_id = load_add_on(sofile);
    78 	if ( library_id == B_ERROR ) {
    79 		loaderror = "BeOS error";
    80 	} else {
    81 		handle = (void *)(library_id);
    82 	}
    83 #elif defined(macintosh)
    84 /* * */
    85 	CFragConnectionID library_id;
    86 	Ptr mainAddr;
    87 	Str255 errName;
    88 	OSErr error;
    89 	char psofile[512];
    90 
    91 	strncpy(psofile, sofile, SDL_TABLESIZE(psofile));
    92 	psofile[SDL_TABLESIZE(psofile)-1] = '\0';
    93 	error = GetSharedLibrary(C2PStr(psofile), kCompiledCFragArch,
    94 			kLoadCFrag, &library_id, &mainAddr, errName);
    95 	switch (error) {
    96 		case noErr:
    97 			break;
    98 		case cfragNoLibraryErr:
    99 			loaderror = "Library not found";
   100 			break;
   101 		case cfragUnresolvedErr:
   102 			loaderror = "Unabled to resolve symbols";
   103 			break;
   104 		case cfragNoPrivateMemErr:
   105 		case cfragNoClientMemErr:
   106 			loaderror = "Out of memory";
   107 			break;
   108 		default:
   109 			loaderror = "Unknown Code Fragment Manager error";
   110 			break;
   111 	}
   112 	if ( loaderror == NULL ) {
   113 		handle = (void *)(library_id);
   114 	}
   115 #endif /* system type */
   116 
   117 	if ( handle == NULL ) {
   118 		SDL_SetError("Failed loading %s: %s", sofile, loaderror);
   119 	}
   120 	return(handle);
   121 }
   122 
   123 void *SDL_LoadFunction(void *handle, const char *name)
   124 {
   125 	void *symbol = NULL;
   126 	const char *loaderror = "SDL_LoadFunction not implemented";
   127 #if defined(USE_DLOPEN)
   128 /* * */
   129 	symbol = dlsym(handle, name);
   130 	if ( symbol == NULL ) {
   131 		loaderror = (char *)dlerror();
   132 	}
   133 #elif defined(WIN32)
   134 /* * */
   135 	char errbuf[512];
   136 
   137 	symbol = (void *)GetProcAddress((HMODULE)handle, name);
   138 	if ( symbol == NULL ) {
   139 		FormatMessage((FORMAT_MESSAGE_IGNORE_INSERTS |
   140 					FORMAT_MESSAGE_FROM_SYSTEM),
   141 				NULL, GetLastError(), 
   142 				MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
   143 				errbuf, SDL_TABLESIZE(errbuf), NULL);
   144 		loaderror = errbuf;
   145 	}
   146 #elif defined(__BEOS__)
   147 /* * */
   148 	image_id library_id = (image_id)handle;
   149 	if ( get_image_symbol(library_id,
   150 		name, B_SYMBOL_TYPE_TEXT, &symbol) != B_NO_ERROR ) {
   151 		loaderror = "Symbol not found";
   152 	}
   153 #elif defined(macintosh)
   154 /* * */
   155 	CFragSymbolClass class;
   156 	CFragConnectionID library_id = (CFragConnectionID)handle;
   157 	char pname[512];
   158 
   159 	strncpy(pname, name, SDL_TABLESIZE(pname));
   160 	pname[SDL_TABLESIZE(pname)-1] = '\0';
   161 	if ( FindSymbol(library_id, C2PStr(pname),
   162 	                (char **)&symbol, &class) != noErr ) {
   163 		loaderror = "Symbol not found";
   164 	}
   165 #endif /* system type */
   166 
   167 	if ( symbol == NULL ) {
   168 		SDL_SetError("Failed loading %s: %s", name, loaderror);
   169 	}
   170 	return(symbol);
   171 }
   172 
   173 void SDL_UnloadObject(void *handle)
   174 {
   175 	if ( handle == NULL ) {
   176 		return;
   177 	}
   178 #if defined(USE_DLOPEN)
   179 /* * */
   180 	dlclose(handle);
   181 #elif defined(WIN32)
   182 /* * */
   183 	FreeLibrary((HMODULE)handle);
   184 #elif defined(__BEOS__)
   185 /* * */
   186 	image_id library_id = (image_id)handle;
   187 	unload_add_on(library_id);
   188 #elif defined(macintosh)
   189 /* * */
   190 	CFragConnectionID library_id = (CFragConnectionID)handle;
   191 	CloseConnection(library_id);
   192 #endif /* system type */
   193 }