pmandin: Added Atari LDG shared object loader

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40652

README.MiNT

@@ -51,6 +51,7 @@ Timer (VBL vector, GNU pth library)
 Joystick and joypad support (Ikbd, Hardware)
 Audio support (Hardware, XBIOS, GSXB, MCSN, STFA, /dev/audio if threads enabled)
 Threads support (Multitasking OS only via GNU pth library)
+Shared object support (using LDG library from http://ldg.atari.org/)
 
 - What is missing:
 CDROM support (Metados, /dev/cdrom)

configure.in

@@ -1577,6 +1577,22 @@ CheckDLOPEN()
     fi
 }
 
+dnl Set up the Atari LDG (shared object loader)
+CheckAtariLdg()
+{
+    AC_ARG_ENABLE(atari-ldg,
+[  --enable-atari-ldg      use Atari LDG for shared object loading [default=yes]],
+                  , enable_atari_ldg=yes)
+    if test x$video_gem = xyes -a x$enable_atari_ldg = xyes; then
+        AC_CHECK_HEADER(ldg.h, have_ldg_hdr=yes)
+        AC_CHECK_LIB(ldg, ldg_open, have_ldg_lib=yes, have_ldg_lib=no, -lgem)
+        if test x$have_ldg_hdr = xyes -a x$have_ldg_lib = xyes; then
+            CFLAGS="$CFLAGS -DENABLE_LDG"
+            SYSTEM_LIBS="$SYSTEM_LIBS -lldg"
+        fi
+    fi
+}
+
 dnl Check for the usbhid(3) library on *BSD
 CheckUSBHID()
 {
@@ -2429,6 +2445,7 @@ case "$target" in
         CheckAtariXbiosVideo
         CheckAtariGemVideo
         CheckAtariAudio
+        CheckAtariLdg
         CheckPTH
         # Set up files for the main() stub
         COPY_ARCH_SRC(src/main, linux, SDL_main.c)

src/SDL_loadso.c

@@ -40,6 +40,9 @@ static char rcsid =
 # include <Strings.h>
 # include <CodeFragments.h>
 # include <Errors.h>
+#elif defined(__MINT__) && defined(ENABLE_LDG)
+# include <gem.h>
+# include <ldg.h>
 #else
 /*#error Unsupported dynamic link environment*/
 #endif /* system type */
@@ -113,6 +116,9 @@ void *SDL_LoadObject(const char *sofile)
 	if ( loaderror == NULL ) {
 		handle = (void *)(library_id);
 	}
+#elif defined(__MINT__) && defined(ENABLE_LDG)
+/* * */
+	handle = (void *)ldg_open((char *)sofile, ldg_global);
 #endif /* system type */
 
 	if ( handle == NULL ) {
@@ -163,6 +169,9 @@ void *SDL_LoadFunction(void *handle, const char *name)
 	                (char **)&symbol, &class) != noErr ) {
 		loaderror = "Symbol not found";
 	}
+#elif defined(__MINT__) && defined(ENABLE_LDG)
+/* * */
+	symbol = (void *)ldg_find((char *)name, (LDG *)handle);
 #endif /* system type */
 
 	if ( symbol == NULL ) {
@@ -193,5 +202,8 @@ void SDL_UnloadObject(void *handle)
 /* * */
 	CFragConnectionID library_id = (CFragConnectionID)handle;
 	CloseConnection(library_id);
+#elif defined(__MINT__) && defined(ENABLE_LDG)
+/* * */
+	ldg_close((LDG *)handle, ldg_global);
 #endif /* system type */
 }