src/glx/x11/dri_glx.c

   1 /**************************************************************************
   2
   3 Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas.
   4 All Rights Reserved.
   5
   6 Permission is hereby granted, free of charge, to any person obtaining a
   7 copy of this software and associated documentation files (the
   8 "Software"), to deal in the Software without restriction, including
   9 without limitation the rights to use, copy, modify, merge, publish,
  10 distribute, sub license, and/or sell copies of the Software, and to
  11 permit persons to whom the Software is furnished to do so, subject to
  12 the following conditions:
  13
  14 The above copyright notice and this permission notice (including the
  15 next paragraph) shall be included in all copies or substantial portions
  16 of the Software.
  17
  18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21 IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR
  22 ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25
  26 **************************************************************************/
  27 /* $XFree86: xc/lib/GL/dri/dri_glx.c,v 1.14 2003/07/16 00:54:00 dawes Exp $ */
  28
  29 /*
  30  * Authors:
  31  *   Kevin E. Martin <kevin@precisioninsight.com>
  32  *   Brian Paul <brian@precisioninsight.com>
  33  *
  34  */
  35
  36 #ifdef GLX_DIRECT_RENDERING
  37
  38 #include <unistd.h>
  39 #include <X11/Xlibint.h>
  40 #include <X11/extensions/Xext.h>
  41 #include <X11/extensions/extutil.h>
  42 #include "glxclient.h"
  43 #include "xf86dri.h"
  44 #include "sarea.h"
  45 #include <stdio.h>
  46 #include <dlfcn.h>
  47 #include "dri_glx.h"
  48 #include <sys/types.h>
  49 #include <stdarg.h>
  50
  51 #ifndef RTLD_NOW
  52 #define RTLD_NOW 0
  53 #endif
  54 #ifndef RTLD_GLOBAL
  55 #define RTLD_GLOBAL 0
  56 #endif
  57
  58
  59 #ifndef DEFAULT_DRIVER_DIR
  60 /* this is normally defined in Mesa/configs/default with DRI_DRIVER_SEARCH_PATH */
  61 #define DEFAULT_DRIVER_DIR "/usr/X11R6/lib/modules/dri"
  62 #endif
  63
  64 static __DRIdriver *Drivers = NULL;
  65
  66
  67 /*
  68  * printf wrappers
  69  */
  70
  71 static void InfoMessageF(const char *f, ...)
  72 {
  73     va_list args;
  74     const char *env;
  75
  76     if ((env = getenv("LIBGL_DEBUG")) && strstr(env, "verbose")) {
  77         fprintf(stderr, "libGL: ");
  78         va_start(args, f);
  79         vfprintf(stderr, f, args);
  80         va_end(args);
  81     }
  82 }
  83
  84 static void ErrorMessageF(const char *f, ...)
  85 {
  86     va_list args;
  87
  88     if (getenv("LIBGL_DEBUG")) {
  89         fprintf(stderr, "libGL error: ");
  90         va_start(args, f);
  91         vfprintf(stderr, f, args);
  92         va_end(args);
  93     }
  94 }
  95
  96
  97 /**
  98  * Extract the ith directory path out of a colon-separated list of paths.  No
  99  * more than \c dirLen characters, including the terminating \c NUL, will be
 100  * written to \c dir.
 101  *
 102  * \param index  Index of path to extract (starting at zero)
 103  * \param paths  The colon-separated list of paths
 104  * \param dirLen Maximum length of result to store in \c dir
 105  * \param dir    Buffer to hold the extracted directory path
 106  *
 107  * \returns
 108  * The number of characters that would have been written to \c dir had there
 109  * been enough room.  This does not include the terminating \c NUL.  When
 110  * extraction fails, zero will be returned.
 111  *
 112  * \todo
 113  * It seems like this function could be rewritten to use \c strchr.
 114  */
 115 static size_t
 116 ExtractDir(int index, const char *paths, int dirLen, char *dir)
 117 {
 118    int i, len;
 119    const char *start, *end;
 120
 121    /* find ith colon */
 122    start = paths;
 123    i = 0;
 124    while (i < index) {
 125       if (*start == ':') {
 126          i++;
 127          start++;
 128       }
 129       else if (*start == 0) {
 130          /* end of string and couldn't find ith colon */
 131          dir[0] = 0;
 132          return 0;
 133       }
 134       else {
 135          start++;
 136       }
 137    }
 138
 139    while (*start == ':')
 140       start++;
 141
 142    /* find next colon, or end of string */
 143    end = start + 1;
 144    while (*end != ':' && *end != 0) {
 145       end++;
 146    }
 147
 148    /* copy string between <start> and <end> into result string */
 149    len = end - start;
 150    if (len > dirLen - 1)
 151       len = dirLen - 1;
 152    strncpy(dir, start, len);
 153    dir[len] = 0;
 154
 155    return( end - start );
 156 }
 157
 158
 159 /**
 160  * Versioned name of the expected \c __driCreateNewScreen function.
 161  *
 162  * The version of the last incompatible loader/driver inteface change is
 163  * appended to the name of the \c __driCreateNewScreen function.  This
 164  * prevents loaders from trying to load drivers that are too old.
 165  *
 166  * \todo
 167  * Create a macro or something so that this is automatically updated.
 168  */
 169 static const char createNewScreenName[] = "__driCreateNewScreen_20050727";
 170
 171
 172 /**
 173  * Try to \c dlopen the named driver.
 174  *
 175  * This function adds the "_dri.so" suffix to the driver name and searches the
 176  * directories specified by the \c LIBGL_DRIVERS_PATH environment variable in
 177  * order to find the driver.
 178  *
 179  * \param driverName - a name like "tdfx", "i810", "mga", etc.
 180  *
 181  * \returns
 182  * A handle from \c dlopen, or \c NULL if driver file not found.
 183  */
 184 static __DRIdriver *OpenDriver(const char *driverName)
 185 {
 186    void *glhandle = NULL;
 187    char *libPaths = NULL;
 188    char libDir[1000];
 189    int i;
 190    __DRIdriver *driver;
 191
 192    /* First, search Drivers list to see if we've already opened this driver */
 193    for (driver = Drivers; driver; driver = driver->next) {
 194       if (strcmp(driver->name, driverName) == 0) {
 195          /* found it */
 196          return driver;
 197       }
 198    }
 199
 200    /* Attempt to make sure libGL symbols will be visible to the driver */
 201    glhandle = dlopen("libGL.so.1", RTLD_NOW | RTLD_GLOBAL);
 202
 203    if (geteuid() == getuid()) {
 204       /* don't allow setuid apps to use LIBGL_DRIVERS_PATH */
 205       libPaths = getenv("LIBGL_DRIVERS_PATH");
 206       if (!libPaths)
 207          libPaths = getenv("LIBGL_DRIVERS_DIR"); /* deprecated */
 208    }
 209    if (!libPaths)
 210       libPaths = DEFAULT_DRIVER_DIR;
 211
 212    for ( i = 0 ; ExtractDir(i, libPaths, 1000, libDir) != 0 ; i++ ) {
 213       char realDriverName[200];
 214       void *handle = NULL;
 215
 216
 217       /* If TLS support is enabled, try to open the TLS version of the driver
 218        * binary first.  If that fails, try the non-TLS version.
 219        */
 220 #ifdef GLX_USE_TLS
 221       snprintf(realDriverName, 200, "%s/tls/%s_dri.so", libDir, driverName);
 222       InfoMessageF("OpenDriver: trying %s\n", realDriverName);
 223       handle = dlopen(realDriverName, RTLD_NOW | RTLD_GLOBAL);
 224 #endif
 225
 226       if ( handle == NULL ) {
 227          snprintf(realDriverName, 200, "%s/%s_dri.so", libDir, driverName);
 228          InfoMessageF("OpenDriver: trying %s\n", realDriverName);
 229          handle = dlopen(realDriverName, RTLD_NOW | RTLD_GLOBAL);
 230       }
 231
 232       if ( handle != NULL ) {
 233          /* allocate __DRIdriver struct */
 234          driver = (__DRIdriver *) Xmalloc(sizeof(__DRIdriver));
 235          if (!driver)
 236             break; /* out of memory! */
 237          /* init the struct */
 238          driver->name = __glXstrdup(driverName);
 239          if (!driver->name) {
 240             Xfree(driver);
 241             driver = NULL;
 242             break; /* out of memory! */
 243          }
 244
 245          driver->createNewScreenFunc = (PFNCREATENEWSCREENFUNC)
 246             dlsym(handle, createNewScreenName);
 247
 248          if ( driver->createNewScreenFunc == NULL ) {
 249             /* If the driver doesn't have this symbol then something's
 250              * really, really wrong.
 251              */
 252             ErrorMessageF("%s not defined in %s_dri.so!\n"
 253                           "Your driver may be too old for this libGL.\n",
 254                           createNewScreenName, driverName);
 255             Xfree(driver);
 256             driver = NULL;
 257             dlclose(handle);
 258             continue;
 259          }
 260          driver->handle = handle;
 261          /* put at head of linked list */
 262          driver->next = Drivers;
 263          Drivers = driver;
 264          break;
 265       }
 266       else {
 267          ErrorMessageF("dlopen %s failed (%s)\n", realDriverName, dlerror());
 268       }
 269    }
 270
 271    if (!driver)
 272       ErrorMessageF("unable to load driver: %s_dri.so\n", driverName);
 273
 274    if (glhandle)
 275       dlclose(glhandle);
 276
 277    return driver;
 278 }
 279
 280
 281 /*
 282  * Given a display pointer and screen number, determine the name of
 283  * the DRI driver for the screen. (I.e. "r128", "tdfx", etc).
 284  * Return True for success, False for failure.
 285  */
 286 static Bool GetDriverName(Display *dpy, int scrNum, char **driverName)
 287 {
 288    int directCapable;
 289    Bool b;
 290    int driverMajor, driverMinor, driverPatch;
 291
 292    *driverName = NULL;
 293
 294    if (!XF86DRIQueryDirectRenderingCapable(dpy, scrNum, &directCapable)) {
 295       ErrorMessageF("XF86DRIQueryDirectRenderingCapable failed\n");
 296       return False;
 297    }
 298    if (!directCapable) {
 299       ErrorMessageF("XF86DRIQueryDirectRenderingCapable returned false\n");
 300       return False;
 301    }
 302
 303    b = XF86DRIGetClientDriverName(dpy, scrNum, &driverMajor, &driverMinor,
 304                                   &driverPatch, driverName);
 305    if (!b) {
 306       ErrorMessageF("Cannot determine driver name for screen %d\n", scrNum);
 307       return False;
 308    }
 309
 310    InfoMessageF("XF86DRIGetClientDriverName: %d.%d.%d %s (screen %d)\n",
 311              driverMajor, driverMinor, driverPatch, *driverName, scrNum);
 312
 313    return True;
 314 }
 315
 316
 317 /*
 318  * Given a display pointer and screen number, return a __DRIdriver handle.
 319  * Return NULL if anything goes wrong.
 320  */
 321 __DRIdriver *driGetDriver(Display *dpy, int scrNum)
 322 {
 323    char *driverName;
 324    if (GetDriverName(dpy, scrNum, &driverName)) {
 325       __DRIdriver *ret;
 326       ret = OpenDriver(driverName);
 327       if (driverName)
 328          Xfree(driverName);
 329       return ret;
 330    }
 331    return NULL;
 332 }
 333
 334
 335 /*
 336  * Exported function for querying the DRI driver for a given screen.
 337  *
 338  * The returned char pointer points to a static array that will be
 339  * overwritten by subsequent calls.
 340  */
 341 const char *glXGetScreenDriver (Display *dpy, int scrNum) {
 342    static char ret[32];
 343    char *driverName;
 344    if (GetDriverName(dpy, scrNum, &driverName)) {
 345       int len;
 346       if (!driverName)
 347          return NULL;
 348       len = strlen (driverName);
 349       if (len >= 31)
 350          return NULL;
 351       memcpy (ret, driverName, len+1);
 352       Xfree(driverName);
 353       return ret;
 354    }
 355    return NULL;
 356 }
 357
 358
 359 /*
 360  * Exported function for obtaining a driver's option list (UTF-8 encoded XML).
 361  *
 362  * The returned char pointer points directly into the driver. Therefore
 363  * it should be treated as a constant.
 364  *
 365  * If the driver was not found or does not support configuration NULL is
 366  * returned.
 367  *
 368  * Note: The driver remains opened after this function returns.
 369  */
 370 const char *glXGetDriverConfig (const char *driverName) {
 371    __DRIdriver *driver = OpenDriver (driverName);
 372    if (driver)
 373       return dlsym (driver->handle, "__driConfigOptions");
 374    else
 375       return NULL;
 376 }
 377
 378
 379 /* This function isn't currently used.
 380  */
 381 static void driDestroyDisplay(Display *dpy, void *private)
 382 {
 383     __DRIdisplayPrivate *pdpyp = (__DRIdisplayPrivate *)private;
 384
 385     if (pdpyp) {
 386         const int numScreens = ScreenCount(dpy);
 387         int i;
 388         for (i = 0; i < numScreens; i++) {
 389             if (pdpyp->libraryHandles[i])
 390                 dlclose(pdpyp->libraryHandles[i]);
 391         }
 392         Xfree(pdpyp->libraryHandles);
 393         Xfree(pdpyp);
 394     }
 395 }
 396
 397
 398 /*
 399  * Allocate, initialize and return a __DRIdisplayPrivate object.
 400  * This is called from __glXInitialize() when we are given a new
 401  * display pointer.
 402  */
 403 void *driCreateDisplay(Display *dpy, __DRIdisplay *pdisp)
 404 {
 405     const int numScreens = ScreenCount(dpy);
 406     __DRIdisplayPrivate *pdpyp;
 407     int eventBase, errorBase;
 408     int major, minor, patch;
 409     int scrn;
 410
 411     /* Initialize these fields to NULL in case we fail.
 412      * If we don't do this we may later get segfaults trying to free random
 413      * addresses when the display is closed.
 414      */
 415     pdisp->private = NULL;
 416     pdisp->destroyDisplay = NULL;
 417
 418     if (!XF86DRIQueryExtension(dpy, &eventBase, &errorBase)) {
 419         return NULL;
 420     }
 421
 422     if (!XF86DRIQueryVersion(dpy, &major, &minor, &patch)) {
 423         return NULL;
 424     }
 425
 426     pdpyp = (__DRIdisplayPrivate *)Xmalloc(sizeof(__DRIdisplayPrivate));
 427     if (!pdpyp) {
 428         return NULL;
 429     }
 430
 431     pdpyp->driMajor = major;
 432     pdpyp->driMinor = minor;
 433     pdpyp->driPatch = patch;
 434
 435     pdisp->destroyDisplay = driDestroyDisplay;
 436
 437     /* allocate array of pointers to createNewScreen funcs */
 438     pdisp->createNewScreen = (PFNCREATENEWSCREENFUNC *)
 439       Xmalloc(numScreens * sizeof(void *));
 440     if (!pdisp->createNewScreen) {
 441        Xfree(pdpyp);
 442        return NULL;
 443     }
 444
 445     /* allocate array of library handles */
 446     pdpyp->libraryHandles = (void **) Xmalloc(numScreens * sizeof(void*));
 447     if (!pdpyp->libraryHandles) {
 448        Xfree(pdisp->createNewScreen);
 449        Xfree(pdpyp);
 450        return NULL;
 451     }
 452
 453     /* dynamically discover DRI drivers for all screens, saving each
 454      * driver's "__driCreateScreen" function pointer.  That's the bootstrap
 455      * entrypoint for all DRI drivers.
 456      */
 457     for (scrn = 0; scrn < numScreens; scrn++) {
 458         __DRIdriver *driver = driGetDriver(dpy, scrn);
 459         if (driver) {
 460            pdisp->createNewScreen[scrn] = driver->createNewScreenFunc;
 461            pdpyp->libraryHandles[scrn] = driver->handle;
 462         }
 463         else {
 464            pdisp->createNewScreen[scrn] = NULL;
 465            pdpyp->libraryHandles[scrn] = NULL;
 466         }
 467     }
 468
 469     return (void *)pdpyp;
 470 }
 471
 472 #endif /* GLX_DIRECT_RENDERING */