src/video/x11/SDL_x11dyn.c

   1 /*
   2     SDL - Simple DirectMedia Layer
   3     Copyright (C) 1997-2009 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 #include "SDL_config.h"
  23
  24 #define DEBUG_DYNAMIC_X11 0
  25
  26 #include "SDL_x11dyn.h"
  27
  28 #if DEBUG_DYNAMIC_X11
  29 #include <stdio.h>
  30 #endif
  31
  32 #ifdef SDL_VIDEO_DRIVER_X11_DYNAMIC
  33
  34 #include "SDL_name.h"
  35 #include "SDL_loadso.h"
  36
  37 typedef struct
  38 {
  39     void *lib;
  40     const char *libname;
  41 } x11dynlib;
  42
  43 #ifndef SDL_VIDEO_DRIVER_X11_DYNAMIC
  44 #define SDL_VIDEO_DRIVER_X11_DYNAMIC NULL
  45 #endif
  46 #ifndef SDL_VIDEO_DRIVER_X11_DYNAMIC_XEXT
  47 #define SDL_VIDEO_DRIVER_X11_DYNAMIC_XEXT NULL
  48 #endif
  49 #ifndef SDL_VIDEO_DRIVER_X11_DYNAMIC_XRENDER
  50 #define SDL_VIDEO_DRIVER_X11_DYNAMIC_XRENDER NULL
  51 #endif
  52 #ifndef SDL_VIDEO_DRIVER_X11_DYNAMIC_XRANDR
  53 #define SDL_VIDEO_DRIVER_X11_DYNAMIC_XRANDR NULL
  54 #endif
  55
  56 static x11dynlib x11libs[] =
  57 {
  58     { NULL, SDL_VIDEO_DRIVER_X11_DYNAMIC },
  59     { NULL, SDL_VIDEO_DRIVER_X11_DYNAMIC_XEXT },
  60     { NULL, SDL_VIDEO_DRIVER_X11_DYNAMIC_XRENDER },
  61     { NULL, SDL_VIDEO_DRIVER_X11_DYNAMIC_XRANDR },
  62 };
  63
  64 static void X11_GetSym(const char *fnname, int *rc, void **fn)
  65 {
  66         int i;
  67         for (i = 0; i < SDL_TABLESIZE(x11libs); i++) {
  68                 if (x11libs[i].lib != NULL)
  69                 {
  70                         *fn = SDL_LoadFunction(x11libs[i].lib, fnname);
  71                         if (*fn != NULL)
  72                                 break;
  73                 }
  74         }
  75
  76         #if DEBUG_DYNAMIC_X11
  77         if (*fn != NULL)
  78                 printf("X11: Found '%s' in %s (%p)\n", fnname, x11libs[i].libname, *fn);
  79         else
  80                 printf("X11: Symbol '%s' NOT FOUND!\n", fnname);
  81         #endif
  82
  83         if (*fn == NULL)
  84                 *rc = 0;  /* kill this module. */
  85 }
  86
  87
  88 /* Define all the function pointers and wrappers... */
  89 #define SDL_X11_MODULE(modname)
  90 #define SDL_X11_SYM(rc,fn,params,args,ret) \
  91         static rc (*p##fn) params = NULL; \
  92         rc fn params { ret p##fn args ; }
  93 #include "SDL_x11sym.h"
  94 #undef SDL_X11_MODULE
  95 #undef SDL_X11_SYM
  96 #endif  /* SDL_VIDEO_DRIVER_X11_DYNAMIC */
  97
  98 /* Annoying varargs entry point... */
  99 #ifdef X_HAVE_UTF8_STRING
 100 XIC (*pXCreateIC)(XIM,...) = NULL;
 101 char *(*pXGetICValues)(XIC, ...) = NULL;
 102 #endif
 103
 104 /* These SDL_X11_HAVE_* flags are here whether you have dynamic X11 or not. */
 105 #define SDL_X11_MODULE(modname) int SDL_X11_HAVE_##modname = 1;
 106 #define SDL_X11_SYM(rc,fn,params,args,ret)
 107 #include "SDL_x11sym.h"
 108 #undef SDL_X11_MODULE
 109 #undef SDL_X11_SYM
 110
 111
 112 static void *SDL_XGetRequest_workaround(Display* dpy, CARD8 type, size_t len)
 113 {
 114         xReq *req;
 115         WORD64ALIGN
 116         if (dpy->bufptr + len > dpy->bufmax)
 117                 _XFlush(dpy);
 118         dpy->last_req = dpy->bufptr;
 119         req = (xReq*)dpy->bufptr;
 120         req->reqType = type;
 121         req->length = len / 4;
 122         dpy->bufptr += len;
 123         dpy->request++;
 124         return req;
 125 }
 126
 127 static int x11_load_refcount = 0;
 128
 129 void SDL_X11_UnloadSymbols(void)
 130 {
 131         #ifdef SDL_VIDEO_DRIVER_X11_DYNAMIC
 132         /* Don't actually unload if more than one module is using the libs... */
 133         if (x11_load_refcount > 0) {
 134                 if (--x11_load_refcount == 0) {
 135                         int i;
 136
 137                         /* set all the function pointers to NULL. */
 138                         #define SDL_X11_MODULE(modname) SDL_X11_HAVE_##modname = 1;
 139                         #define SDL_X11_SYM(rc,fn,params,args,ret) p##fn = NULL;
 140                         #include "SDL_x11sym.h"
 141                         #undef SDL_X11_MODULE
 142                         #undef SDL_X11_SYM
 143
 144                         #ifdef X_HAVE_UTF8_STRING
 145                         pXCreateIC = NULL;
 146                         pXGetICValues = NULL;
 147                         #endif
 148
 149                         for (i = 0; i < SDL_TABLESIZE(x11libs); i++) {
 150                                 if (x11libs[i].lib != NULL) {
 151                                         SDL_UnloadObject(x11libs[i].lib);
 152                                         x11libs[i].lib = NULL;
 153                                 }
 154                         }
 155                 }
 156         }
 157         #endif
 158 }
 159
 160 /* returns non-zero if all needed symbols were loaded. */
 161 int SDL_X11_LoadSymbols(void)
 162 {
 163         int rc = 1;  /* always succeed if not using Dynamic X11 stuff. */
 164
 165         #ifdef SDL_VIDEO_DRIVER_X11_DYNAMIC
 166         /* deal with multiple modules (dga, x11, etc) needing these symbols... */
 167         if (x11_load_refcount++ == 0) {
 168                 int i;
 169                 int *thismod = NULL;
 170                 for (i = 0; i < SDL_TABLESIZE(x11libs); i++) {
 171                         if (x11libs[i].libname != NULL) {
 172                                 x11libs[i].lib = SDL_LoadObject(x11libs[i].libname);
 173                         }
 174                 }
 175                 #define SDL_X11_MODULE(modname) thismod = &SDL_X11_HAVE_##modname;
 176                 #define SDL_X11_SYM(a,fn,x,y,z) X11_GetSym(#fn,thismod,(void**)&p##fn);
 177                 #include "SDL_x11sym.h"
 178                 #undef SDL_X11_MODULE
 179                 #undef SDL_X11_SYM
 180
 181                 #ifdef X_HAVE_UTF8_STRING
 182                 X11_GetSym("XCreateIC",&SDL_X11_HAVE_UTF8,(void **)&pXCreateIC);
 183                 X11_GetSym("XGetICValues",&SDL_X11_HAVE_UTF8,(void **)&pXGetICValues);
 184                 #endif
 185
 186                 /*
 187                  * In case we're built with newer Xlib headers, we need to make sure
 188                  *  that _XGetRequest() is available, even on older systems.
 189                  *  Otherwise, various Xlib macros we use will call a NULL pointer.
 190                  */
 191                 if (!SDL_X11_HAVE_XGETREQUEST) {
 192                         p_XGetRequest = SDL_XGetRequest_workaround;
 193                 }
 194
 195                 if (SDL_X11_HAVE_BASEXLIB) {  /* all required symbols loaded. */
 196                         SDL_ClearError();
 197                 } else {
 198                         SDL_X11_UnloadSymbols();  /* in case something got loaded... */
 199                         rc = 0;
 200                 }
 201         }
 202         #else
 203                 #if DEBUG_DYNAMIC_X11
 204                 printf("X11: No dynamic X11 support in this build of SDL.\n");
 205                 #endif
 206                 #ifdef X_HAVE_UTF8_STRING
 207                 pXCreateIC = XCreateIC;
 208                 pXGetICValues = XGetICValues;
 209                 #endif
 210         #endif
 211
 212         return rc;
 213 }
 214
 215 /* end of SDL_x11dyn.c ... */
 216