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.

WhatsNew

@@ -4,6 +4,12 @@ This is a list of API changes in SDL's version history.
 Version 1.0:
 
 1.2.4:
+	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.
+
 	Added SDL_LockRect() and SDL_UnlockRect() to lock a portion of a
 	surface.  This may be more efficient than a full lock if you are
 	using a hardware surface and plan to make a few changes to small

configure.in

@@ -324,12 +324,26 @@ CheckESD()
 [  --enable-esd            support the Enlightened Sound Daemon [default=yes]],
                   , enable_esd=yes)
     if test x$enable_audio = xyes -a x$enable_esd = xyes; then
-        AM_PATH_ESD(0.2.8, [
-            CFLAGS="$CFLAGS -DESD_SUPPORT $ESD_CFLAGS"
-            SYSTEM_LIBS="$SYSTEM_LIBS $ESD_LIBS"
+	use_esd=no
+        AM_PATH_ESD(0.2.8, use_esd=yes)
+	if test x$use_esd = xyes; then
+            AC_ARG_ENABLE(esd-shared,
+[  --enable-esd-shared     dynamically load ESD support [default=yes]],
+                          , enable_esd_shared=yes)
+            esd_lib_spec=`echo $ESD_LIBS | sed 's/.*-L\([[^ ]]*\).*/\1\/libesd.so.*/'`
+	    esd_lib=`ls $esd_lib_spec | head -1 | sed 's/.*\/\(.*\)/\1/'`
+	    echo "-- $esd_lib_spec -> $esd_lib"
+            if test x$enable_dlopen = xyes && \
+               test x$enable_esd_shared = xyes && test x$esd_lib != x; then
+                CFLAGS="$CFLAGS -DESD_SUPPORT -DESD_DYNAMIC=\$(esd_lib) $ESD_CFLAGS"
+		AC_SUBST(esd_lib)
+            else
+                CFLAGS="$CFLAGS -DESD_SUPPORT $ESD_CFLAGS"
+                SYSTEM_LIBS="$SYSTEM_LIBS $ESD_LIBS"
+            fi
             AUDIO_SUBDIRS="$AUDIO_SUBDIRS esd"
             AUDIO_DRIVERS="$AUDIO_DRIVERS esd/libaudio_esd.la"
-        ])
+        fi
     fi
 }
 
@@ -359,8 +373,20 @@ CheckARTSC()
             CFLAGS="$save_CFLAGS"
             AC_MSG_RESULT($audio_arts)
             if test x$audio_arts = xyes; then
-                CFLAGS="$CFLAGS -DARTSC_SUPPORT $ARTSC_CFLAGS"
-                SYSTEM_LIBS="$SYSTEM_LIBS $ARTSC_LIBS"
+                AC_ARG_ENABLE(arts-shared,
+[  --enable-arts-shared     dynamically load ESD support [default=yes]],
+                              , enable_arts_shared=yes)
+                arts_lib_spec=`echo $ARTSC_LIBS | sed 's/.*-L\([[^ ]]*\).*/\1\/libarts.so.*/'`
+	        arts_lib=`ls $arts_lib_spec | head -1 | sed 's/.*\/\(.*\)/\1/'`
+	        echo "-- $arts_lib_spec -> $arts_lib"
+                if test x$enable_dlopen = xyes && \
+                   test x$enable_arts_shared = xyes && test x$arts_lib != x; then
+                    CFLAGS="$CFLAGS -DARTSC_SUPPORT -DARTSC_DYNAMIC=\$(arts_lib) $ARTSC_CFLAGS"
+		    AC_SUBST(arts_lib)
+                else
+                    CFLAGS="$CFLAGS -DARTSC_SUPPORT $ARTSC_CFLAGS"
+                    SYSTEM_LIBS="$SYSTEM_LIBS $ARTSC_LIBS"
+                fi
                 AUDIO_SUBDIRS="$AUDIO_SUBDIRS arts"
                 AUDIO_DRIVERS="$AUDIO_DRIVERS arts/libaudio_arts.la"
             fi
@@ -1353,11 +1379,36 @@ CheckQUARTZ()
     VIDEO_DRIVERS="$VIDEO_DRIVERS quartz/libvideo_quartz.la"
 }
 
+dnl Check for the dlfcn.h interface for dynamically loading objects
+CheckDLOPEN()
+{
+    AC_ARG_ENABLE(dlopen,
+[  --enable-dlopen         use dlopen for shared object loading [default=yes]],
+                  , enable_dlopen=yes)
+    if test x$enable_dlopen = xyes; then
+        AC_MSG_CHECKING(for dlopen)
+        use_dlopen=no
+        AC_TRY_COMPILE([
+         #include <dlfcn.h>
+        ],[
+        ],[
+        use_dlopen=yes
+        ])
+        AC_MSG_RESULT($use_dlopen)
+
+        if test x$use_dlopen = xyes; then
+            CFLAGS="$CFLAGS -DUSE_DLOPEN"
+            SYSTEM_LIBS="$SYSTEM_LIBS -ldl"
+        fi
+    fi
+}
+
 case "$target" in
     *-*-linux*)
         ARCH=linux
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNASM
         CheckOSS
         CheckALSA
@@ -1429,6 +1480,7 @@ case "$target" in
         ARCH=bsdi
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1480,6 +1532,7 @@ case "$target" in
         ARCH=freebsd
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckVGL
         CheckNASM
         CheckOSS
@@ -1535,6 +1588,7 @@ case "$target" in
         ARCH=netbsd
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1588,6 +1642,7 @@ case "$target" in
         ARCH=openbsd
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckOPENBSDAUDIO
         CheckNASM
         CheckOSS
@@ -1647,6 +1702,7 @@ case "$target" in
         ARCH=sysv5
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1696,6 +1752,7 @@ case "$target" in
         CFLAGS="$CFLAGS -D__ELF__" # Fix for nasm on Solaris x86
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1744,6 +1801,7 @@ case "$target" in
         ARCH=irix
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckDMEDIA
         CheckESD
         CheckNAS
@@ -1806,6 +1864,7 @@ case "$target" in
         ARCH=hpux
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckOSS
         CheckNAS
         CheckX11
@@ -1853,6 +1912,7 @@ case "$target" in
         ARCH=aix
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckOSS
         CheckNAS
         CheckX11
@@ -1898,6 +1958,7 @@ case "$target" in
         ARCH=osf
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNAS
         CheckX11
         CheckGGI
@@ -1944,6 +2005,7 @@ case "$target" in
         ARCH=qnx
         CheckDummyVideo
         CheckDiskAudio
+	CheckDLOPEN
         CheckNAS
         CheckPHOTON
         CheckX11

docs.html

@@ -16,6 +16,7 @@ <H2>
 Major changes since SDL 1.0.0:
 </H2>
 <UL>
+	<LI> 1.2.4: Added shared object loading functions in SDL_loadso.h
 	<LI> 1.2.4: Added SDL_LockRect() and SDL_UnlockRect()
 	<LI> 1.2.4: Incorporated XFree86 extension libraries into the source
 	<LI> 1.2.4: Added initial support for Atari (thanks Patrice!)

include/Makefile.am

@@ -18,6 +18,7 @@ libSDLinclude_HEADERS =		\
 	SDL_joystick.h		\
 	SDL_keyboard.h		\
 	SDL_keysym.h		\
+	SDL_loadso.h		\
 	SDL_main.h		\
 	SDL_mouse.h		\
 	SDL_mutex.h		\

include/SDL.h

@@ -34,6 +34,7 @@ static char rcsid =
 #include "SDL_types.h"
 #include "SDL_getenv.h"
 #include "SDL_error.h"
+#include "SDL_loadso.h"
 #include "SDL_rwops.h"
 #include "SDL_timer.h"
 #include "SDL_audio.h"

include/SDL_loadso.h

@@ -0,0 +1,61 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public
+    License along with this library; if not, write to the Free
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+
+#ifdef SAVE_RCSID
+static char rcsid =
+ "@(#) $Id$";
+#endif
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+/* System dependent library loading routines                           */
+
+#ifndef _SDL_loadso_h
+#define _SDL_loadso_h
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This function dynamically loads a shared object and returns a pointer
+ * to the object handle (or NULL if there was an error).
+ * The 'sofile' parameter is a system dependent name of the object file.
+ */
+extern DECLSPEC void *SDL_LoadObject(const char *sofile);
+
+/* Given an object handle, this function looks up the address of the
+ * named function in the shared object and returns it.  This address
+ * is no longer valid after calling SDL_UnloadObject().
+ */
+extern DECLSPEC void *SDL_LoadFunction(void *handle, const char *name);
+
+/* Unload a shared object from memory */
+extern DECLSPEC void SDL_UnloadObject(void *handle);
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include "close_code.h"
+
+#endif /* _SDL_loadso_h */

include/SDL_name.h

@@ -6,8 +6,6 @@
 #define NeedFunctionPrototypes 1
 #endif
 
-#ifndef SDL_NAME
 #define SDL_NAME(X)	SDL_##X
-#endif
 
 #endif /* _SDLname_h_ */

src/Makefile.am

@@ -37,5 +37,6 @@ GENERAL_SRCS = 		\
 	SDL_error_c.h		\
 	SDL_fatal.c		\
 	SDL_fatal.h		\
-	SDL_getenv.c
+	SDL_getenv.c		\
+	SDL_loadso.c