src/mesa/drivers/dri/common/utils.c

   1 /*
   2  * (C) Copyright IBM Corporation 2002, 2004
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * on the rights to use, copy, modify, merge, publish, distribute, sub
   9  * license, and/or sell copies of the Software, and to permit persons to whom
  10  * the Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
  19  * VA LINUX SYSTEM, IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  22  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file utils.c
  27  * Utility functions for DRI drivers.
  28  *
  29  * \author Ian Romanick <idr@us.ibm.com>
  30  */
  31
  32 #include <string.h>
  33 #include <stdlib.h>
  34 #include "main/mtypes.h"
  35 #include "main/cpuinfo.h"
  36 #include "main/extensions.h"
  37 #include "utils.h"
  38
  39
  40 /**
  41  * Print message to \c stderr if the \c LIBGL_DEBUG environment variable
  42  * is set.
  43  *
  44  * Is called from the drivers.
  45  *
  46  * \param f \c printf like format string.
  47  */
  48 void
  49 __driUtilMessage(const char *f, ...)
  50 {
  51     va_list args;
  52
  53     if (getenv("LIBGL_DEBUG")) {
  54         fprintf(stderr, "libGL: ");
  55         va_start(args, f);
  56         vfprintf(stderr, f, args);
  57         va_end(args);
  58         fprintf(stderr, "\n");
  59     }
  60 }
  61
  62
  63 unsigned
  64 driParseDebugString( const char * debug,
  65                      const struct dri_debug_control * control  )
  66 {
  67    unsigned   flag;
  68
  69
  70    flag = 0;
  71    if ( debug != NULL ) {
  72       while( control->string != NULL ) {
  73          if ( !strcmp( debug, "all" ) ||
  74               strstr( debug, control->string ) != NULL ) {
  75             flag |= control->flag;
  76          }
  77
  78          control++;
  79       }
  80    }
  81
  82    return flag;
  83 }
  84
  85
  86
  87 /**
  88  * Create the \c GL_RENDERER string for DRI drivers.
  89  *
  90  * Almost all DRI drivers use a \c GL_RENDERER string of the form:
  91  *
  92  *    "Mesa DRI <chip> <driver date> <AGP speed) <CPU information>"
  93  *
  94  * Using the supplied chip name, driver data, and AGP speed, this function
  95  * creates the string.
  96  *
  97  * \param buffer         Buffer to hold the \c GL_RENDERER string.
  98  * \param hardware_name  Name of the hardware.
  99  * \param agp_mode       AGP mode (speed).
 100  *
 101  * \returns
 102  * The length of the string stored in \c buffer.  This does \b not include
 103  * the terminating \c NUL character.
 104  */
 105 unsigned
 106 driGetRendererString( char * buffer, const char * hardware_name,
 107                       GLuint agp_mode )
 108 {
 109    unsigned offset;
 110    char *cpu;
 111
 112    offset = sprintf( buffer, "Mesa DRI %s", hardware_name );
 113
 114    /* Append any AGP-specific information.
 115     */
 116    switch ( agp_mode ) {
 117    case 1:
 118    case 2:
 119    case 4:
 120    case 8:
 121       offset += sprintf( & buffer[ offset ], " AGP %ux", agp_mode );
 122       break;
 123
 124    default:
 125       break;
 126    }
 127
 128    /* Append any CPU-specific information.
 129     */
 130    cpu = _mesa_get_cpu_string();
 131    if (cpu) {
 132       offset += sprintf(buffer + offset, " %s", cpu);
 133       free(cpu);
 134    }
 135
 136    return offset;
 137 }
 138
 139
 140 /**
 141  * Creates a set of \c struct gl_config that a driver will expose.
 142  *
 143  * A set of \c struct gl_config will be created based on the supplied
 144  * parameters.  The number of modes processed will be 2 *
 145  * \c num_depth_stencil_bits * \c num_db_modes.
 146  *
 147  * For the most part, data is just copied from \c depth_bits, \c stencil_bits,
 148  * \c db_modes, and \c visType into each \c struct gl_config element.
 149  * However, the meanings of \c fb_format and \c fb_type require further
 150  * explanation.  The \c fb_format specifies which color components are in
 151  * each pixel and what the default order is.  For example, \c GL_RGB specifies
 152  * that red, green, blue are available and red is in the "most significant"
 153  * position and blue is in the "least significant".  The \c fb_type specifies
 154  * the bit sizes of each component and the actual ordering.  For example, if
 155  * \c GL_UNSIGNED_SHORT_5_6_5_REV is specified with \c GL_RGB, bits [15:11]
 156  * are the blue value, bits [10:5] are the green value, and bits [4:0] are
 157  * the red value.
 158  *
 159  * One sublte issue is the combination of \c GL_RGB  or \c GL_BGR and either
 160  * of the \c GL_UNSIGNED_INT_8_8_8_8 modes.  The resulting mask values in the
 161  * \c struct gl_config structure is \b identical to the \c GL_RGBA or
 162  * \c GL_BGRA case, except the \c alphaMask is zero.  This means that, as
 163  * far as this routine is concerned, \c GL_RGB with \c GL_UNSIGNED_INT_8_8_8_8
 164  * still uses 32-bits.
 165  *
 166  * If in doubt, look at the tables used in the function.
 167  *
 168  * \param ptr_to_modes  Pointer to a pointer to a linked list of
 169  *                      \c struct gl_config.  Upon completion, a pointer to
 170  *                      the next element to be process will be stored here.
 171  *                      If the function fails and returns \c GL_FALSE, this
 172  *                      value will be unmodified, but some elements in the
 173  *                      linked list may be modified.
 174  * \param fb_format     Format of the framebuffer.  Currently only \c GL_RGB,
 175  *                      \c GL_RGBA, \c GL_BGR, and \c GL_BGRA are supported.
 176  * \param fb_type       Type of the pixels in the framebuffer.  Currently only
 177  *                      \c GL_UNSIGNED_SHORT_5_6_5,
 178  *                      \c GL_UNSIGNED_SHORT_5_6_5_REV,
 179  *                      \c GL_UNSIGNED_INT_8_8_8_8, and
 180  *                      \c GL_UNSIGNED_INT_8_8_8_8_REV are supported.
 181  * \param depth_bits    Array of depth buffer sizes to be exposed.
 182  * \param stencil_bits  Array of stencil buffer sizes to be exposed.
 183  * \param num_depth_stencil_bits  Number of entries in both \c depth_bits and
 184  *                      \c stencil_bits.
 185  * \param db_modes      Array of buffer swap modes.  If an element has a
 186  *                      value of \c GLX_NONE, then it represents a
 187  *                      single-buffered mode.  Other valid values are
 188  *                      \c GLX_SWAP_EXCHANGE_OML, \c GLX_SWAP_COPY_OML, and
 189  *                      \c GLX_SWAP_UNDEFINED_OML.  See the
 190  *                      GLX_OML_swap_method extension spec for more details.
 191  * \param num_db_modes  Number of entries in \c db_modes.
 192  * \param msaa_samples  Array of msaa sample count. 0 represents a visual
 193  *                      without a multisample buffer.
 194  * \param num_msaa_modes Number of entries in \c msaa_samples.
 195  * \param visType       GLX visual type.  Usually either \c GLX_TRUE_COLOR or
 196  *                      \c GLX_DIRECT_COLOR.
 197  *
 198  * \returns
 199  * \c GL_TRUE on success or \c GL_FALSE on failure.  Currently the only
 200  * cause of failure is a bad parameter (i.e., unsupported \c fb_format or
 201  * \c fb_type).
 202  *
 203  * \todo
 204  * There is currently no way to support packed RGB modes (i.e., modes with
 205  * exactly 3 bytes per pixel) or floating-point modes.  This could probably
 206  * be done by creating some new, private enums with clever names likes
 207  * \c GL_UNSIGNED_3BYTE_8_8_8, \c GL_4FLOAT_32_32_32_32,
 208  * \c GL_4HALF_16_16_16_16, etc.  We can cross that bridge when we come to it.
 209  */
 210 __DRIconfig **
 211 driCreateConfigs(GLenum fb_format, GLenum fb_type,
 212                  const uint8_t * depth_bits, const uint8_t * stencil_bits,
 213                  unsigned num_depth_stencil_bits,
 214                  const GLenum * db_modes, unsigned num_db_modes,
 215                  const uint8_t * msaa_samples, unsigned num_msaa_modes,
 216                  GLboolean enable_accum)
 217 {
 218    static const uint8_t bits_table[4][4] = {
 219      /* R  G  B  A */
 220       { 3, 3, 2, 0 }, /* Any GL_UNSIGNED_BYTE_3_3_2 */
 221       { 5, 6, 5, 0 }, /* Any GL_UNSIGNED_SHORT_5_6_5 */
 222       { 8, 8, 8, 0 }, /* Any RGB with any GL_UNSIGNED_INT_8_8_8_8 */
 223       { 8, 8, 8, 8 }  /* Any RGBA with any GL_UNSIGNED_INT_8_8_8_8 */
 224    };
 225
 226    static const uint32_t masks_table_rgb[6][4] = {
 227       { 0x000000E0, 0x0000001C, 0x00000003, 0x00000000 }, /* 3_3_2       */
 228       { 0x00000007, 0x00000038, 0x000000C0, 0x00000000 }, /* 2_3_3_REV   */
 229       { 0x0000F800, 0x000007E0, 0x0000001F, 0x00000000 }, /* 5_6_5       */
 230       { 0x0000001F, 0x000007E0, 0x0000F800, 0x00000000 }, /* 5_6_5_REV   */
 231       { 0xFF000000, 0x00FF0000, 0x0000FF00, 0x00000000 }, /* 8_8_8_8     */
 232       { 0x000000FF, 0x0000FF00, 0x00FF0000, 0x00000000 }  /* 8_8_8_8_REV */
 233    };
 234
 235    static const uint32_t masks_table_rgba[6][4] = {
 236       { 0x000000E0, 0x0000001C, 0x00000003, 0x00000000 }, /* 3_3_2       */
 237       { 0x00000007, 0x00000038, 0x000000C0, 0x00000000 }, /* 2_3_3_REV   */
 238       { 0x0000F800, 0x000007E0, 0x0000001F, 0x00000000 }, /* 5_6_5       */
 239       { 0x0000001F, 0x000007E0, 0x0000F800, 0x00000000 }, /* 5_6_5_REV   */
 240       { 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF }, /* 8_8_8_8     */
 241       { 0x000000FF, 0x0000FF00, 0x00FF0000, 0xFF000000 }, /* 8_8_8_8_REV */
 242    };
 243
 244    static const uint32_t masks_table_bgr[6][4] = {
 245       { 0x00000007, 0x00000038, 0x000000C0, 0x00000000 }, /* 3_3_2       */
 246       { 0x000000E0, 0x0000001C, 0x00000003, 0x00000000 }, /* 2_3_3_REV   */
 247       { 0x0000001F, 0x000007E0, 0x0000F800, 0x00000000 }, /* 5_6_5       */
 248       { 0x0000F800, 0x000007E0, 0x0000001F, 0x00000000 }, /* 5_6_5_REV   */
 249       { 0x0000FF00, 0x00FF0000, 0xFF000000, 0x00000000 }, /* 8_8_8_8     */
 250       { 0x00FF0000, 0x0000FF00, 0x000000FF, 0x00000000 }, /* 8_8_8_8_REV */
 251    };
 252
 253    static const uint32_t masks_table_bgra[6][4] = {
 254       { 0x00000007, 0x00000038, 0x000000C0, 0x00000000 }, /* 3_3_2       */
 255       { 0x000000E0, 0x0000001C, 0x00000003, 0x00000000 }, /* 2_3_3_REV   */
 256       { 0x0000001F, 0x000007E0, 0x0000F800, 0x00000000 }, /* 5_6_5       */
 257       { 0x0000F800, 0x000007E0, 0x0000001F, 0x00000000 }, /* 5_6_5_REV   */
 258       { 0x0000FF00, 0x00FF0000, 0xFF000000, 0x000000FF }, /* 8_8_8_8     */
 259       { 0x00FF0000, 0x0000FF00, 0x000000FF, 0xFF000000 }, /* 8_8_8_8_REV */
 260    };
 261
 262    static const uint8_t bytes_per_pixel[6] = {
 263       1, /* 3_3_2       */
 264       1, /* 2_3_3_REV   */
 265       2, /* 5_6_5       */
 266       2, /* 5_6_5_REV   */
 267       4, /* 8_8_8_8     */
 268       4  /* 8_8_8_8_REV */
 269    };
 270
 271    const uint8_t  * bits;
 272    const uint32_t * masks;
 273    int index;
 274    __DRIconfig **configs, **c;
 275    struct gl_config *modes;
 276    unsigned i, j, k, h;
 277    unsigned num_modes;
 278    unsigned num_accum_bits = (enable_accum) ? 2 : 1;
 279
 280    switch ( fb_type ) {
 281       case GL_UNSIGNED_BYTE_3_3_2:
 282          index = 0;
 283          break;
 284       case GL_UNSIGNED_BYTE_2_3_3_REV:
 285          index = 1;
 286          break;
 287       case GL_UNSIGNED_SHORT_5_6_5:
 288          index = 2;
 289          break;
 290       case GL_UNSIGNED_SHORT_5_6_5_REV:
 291          index = 3;
 292          break;
 293       case GL_UNSIGNED_INT_8_8_8_8:
 294          index = 4;
 295          break;
 296       case GL_UNSIGNED_INT_8_8_8_8_REV:
 297          index = 5;
 298          break;
 299       default:
 300          fprintf( stderr, "[%s:%u] Unknown framebuffer type 0x%04x.\n",
 301                __FUNCTION__, __LINE__, fb_type );
 302          return NULL;
 303    }
 304
 305
 306    /* Valid types are GL_UNSIGNED_SHORT_5_6_5 and GL_UNSIGNED_INT_8_8_8_8 and
 307     * the _REV versions.
 308     *
 309     * Valid formats are GL_RGBA, GL_RGB, and GL_BGRA.
 310     */
 311
 312    switch ( fb_format ) {
 313       case GL_RGB:
 314          masks = masks_table_rgb[ index ];
 315          break;
 316
 317       case GL_RGBA:
 318          masks = masks_table_rgba[ index ];
 319          break;
 320
 321       case GL_BGR:
 322          masks = masks_table_bgr[ index ];
 323          break;
 324
 325       case GL_BGRA:
 326          masks = masks_table_bgra[ index ];
 327          break;
 328
 329       default:
 330          fprintf( stderr, "[%s:%u] Unknown framebuffer format 0x%04x.\n",
 331                __FUNCTION__, __LINE__, fb_format );
 332          return NULL;
 333    }
 334
 335    switch ( bytes_per_pixel[ index ] ) {
 336       case 1:
 337          bits = bits_table[0];
 338          break;
 339       case 2:
 340          bits = bits_table[1];
 341          break;
 342       default:
 343          bits = ((fb_format == GL_RGB) || (fb_format == GL_BGR))
 344             ? bits_table[2]
 345             : bits_table[3];
 346          break;
 347    }
 348
 349    num_modes = num_depth_stencil_bits * num_db_modes * num_accum_bits * num_msaa_modes;
 350    configs = calloc(1, (num_modes + 1) * sizeof *configs);
 351    if (configs == NULL)
 352        return NULL;
 353
 354     c = configs;
 355     for ( k = 0 ; k < num_depth_stencil_bits ; k++ ) {
 356         for ( i = 0 ; i < num_db_modes ; i++ ) {
 357             for ( h = 0 ; h < num_msaa_modes; h++ ) {
 358                 for ( j = 0 ; j < num_accum_bits ; j++ ) {
 359                     *c = malloc (sizeof **c);
 360                     modes = &(*c)->modes;
 361                     c++;
 362
 363                     memset(modes, 0, sizeof *modes);
 364                     modes->redBits   = bits[0];
 365                     modes->greenBits = bits[1];
 366                     modes->blueBits  = bits[2];
 367                     modes->alphaBits = bits[3];
 368                     modes->redMask   = masks[0];
 369                     modes->greenMask = masks[1];
 370                     modes->blueMask  = masks[2];
 371                     modes->alphaMask = masks[3];
 372                     modes->rgbBits   = modes->redBits + modes->greenBits
 373                         + modes->blueBits + modes->alphaBits;
 374
 375                     modes->accumRedBits   = 16 * j;
 376                     modes->accumGreenBits = 16 * j;
 377                     modes->accumBlueBits  = 16 * j;
 378                     modes->accumAlphaBits = (masks[3] != 0) ? 16 * j : 0;
 379                     modes->visualRating = (j == 0) ? GLX_NONE : GLX_SLOW_CONFIG;
 380
 381                     modes->stencilBits = stencil_bits[k];
 382                     modes->depthBits = depth_bits[k];
 383
 384                     modes->transparentPixel = GLX_NONE;
 385                     modes->transparentRed = GLX_DONT_CARE;
 386                     modes->transparentGreen = GLX_DONT_CARE;
 387                     modes->transparentBlue = GLX_DONT_CARE;
 388                     modes->transparentAlpha = GLX_DONT_CARE;
 389                     modes->transparentIndex = GLX_DONT_CARE;
 390                     modes->rgbMode = GL_TRUE;
 391
 392                     if ( db_modes[i] == GLX_NONE ) {
 393                         modes->doubleBufferMode = GL_FALSE;
 394                     }
 395                     else {
 396                         modes->doubleBufferMode = GL_TRUE;
 397                         modes->swapMethod = db_modes[i];
 398                     }
 399
 400                     modes->samples = msaa_samples[h];
 401                     modes->sampleBuffers = modes->samples ? 1 : 0;
 402
 403
 404                     modes->haveAccumBuffer = ((modes->accumRedBits +
 405                                            modes->accumGreenBits +
 406                                            modes->accumBlueBits +
 407                                            modes->accumAlphaBits) > 0);
 408                     modes->haveDepthBuffer = (modes->depthBits > 0);
 409                     modes->haveStencilBuffer = (modes->stencilBits > 0);
 410
 411                     modes->bindToTextureRgb = GL_TRUE;
 412                     modes->bindToTextureRgba = GL_TRUE;
 413                     modes->bindToMipmapTexture = GL_FALSE;
 414                     modes->bindToTextureTargets =
 415                         __DRI_ATTRIB_TEXTURE_1D_BIT |
 416                         __DRI_ATTRIB_TEXTURE_2D_BIT |
 417                         __DRI_ATTRIB_TEXTURE_RECTANGLE_BIT;
 418
 419                     modes->sRGBCapable = GL_FALSE;
 420                 }
 421             }
 422         }
 423     }
 424     *c = NULL;
 425
 426     return configs;
 427 }
 428
 429 __DRIconfig **driConcatConfigs(__DRIconfig **a,
 430                                __DRIconfig **b)
 431 {
 432     __DRIconfig **all;
 433     int i, j, index;
 434
 435     i = 0;
 436     while (a[i] != NULL)
 437         i++;
 438     j = 0;
 439     while (b[j] != NULL)
 440         j++;
 441
 442     all = malloc((i + j + 1) * sizeof *all);
 443     index = 0;
 444     for (i = 0; a[i] != NULL; i++)
 445         all[index++] = a[i];
 446     for (j = 0; b[j] != NULL; j++)
 447         all[index++] = b[j];
 448     all[index++] = NULL;
 449
 450     free(a);
 451     free(b);
 452
 453     return all;
 454 }
 455
 456 #define __ATTRIB(attrib, field) \
 457     { attrib, offsetof(struct gl_config, field) }
 458
 459 static const struct { unsigned int attrib, offset; } attribMap[] = {
 460     __ATTRIB(__DRI_ATTRIB_BUFFER_SIZE,                  rgbBits),
 461     __ATTRIB(__DRI_ATTRIB_LEVEL,                        level),
 462     __ATTRIB(__DRI_ATTRIB_RED_SIZE,                     redBits),
 463     __ATTRIB(__DRI_ATTRIB_GREEN_SIZE,                   greenBits),
 464     __ATTRIB(__DRI_ATTRIB_BLUE_SIZE,                    blueBits),
 465     __ATTRIB(__DRI_ATTRIB_ALPHA_SIZE,                   alphaBits),
 466     __ATTRIB(__DRI_ATTRIB_DEPTH_SIZE,                   depthBits),
 467     __ATTRIB(__DRI_ATTRIB_STENCIL_SIZE,                 stencilBits),
 468     __ATTRIB(__DRI_ATTRIB_ACCUM_RED_SIZE,               accumRedBits),
 469     __ATTRIB(__DRI_ATTRIB_ACCUM_GREEN_SIZE,             accumGreenBits),
 470     __ATTRIB(__DRI_ATTRIB_ACCUM_BLUE_SIZE,              accumBlueBits),
 471     __ATTRIB(__DRI_ATTRIB_ACCUM_ALPHA_SIZE,             accumAlphaBits),
 472     __ATTRIB(__DRI_ATTRIB_SAMPLE_BUFFERS,               sampleBuffers),
 473     __ATTRIB(__DRI_ATTRIB_SAMPLES,                      samples),
 474     __ATTRIB(__DRI_ATTRIB_DOUBLE_BUFFER,                doubleBufferMode),
 475     __ATTRIB(__DRI_ATTRIB_STEREO,                       stereoMode),
 476     __ATTRIB(__DRI_ATTRIB_AUX_BUFFERS,                  numAuxBuffers),
 477     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_TYPE,             transparentPixel),
 478     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_INDEX_VALUE,      transparentPixel),
 479     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_RED_VALUE,        transparentRed),
 480     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_GREEN_VALUE,      transparentGreen),
 481     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_BLUE_VALUE,       transparentBlue),
 482     __ATTRIB(__DRI_ATTRIB_TRANSPARENT_ALPHA_VALUE,      transparentAlpha),
 483     __ATTRIB(__DRI_ATTRIB_FLOAT_MODE,                   floatMode),
 484     __ATTRIB(__DRI_ATTRIB_RED_MASK,                     redMask),
 485     __ATTRIB(__DRI_ATTRIB_GREEN_MASK,                   greenMask),
 486     __ATTRIB(__DRI_ATTRIB_BLUE_MASK,                    blueMask),
 487     __ATTRIB(__DRI_ATTRIB_ALPHA_MASK,                   alphaMask),
 488     __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_WIDTH,            maxPbufferWidth),
 489     __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_HEIGHT,           maxPbufferHeight),
 490     __ATTRIB(__DRI_ATTRIB_MAX_PBUFFER_PIXELS,           maxPbufferPixels),
 491     __ATTRIB(__DRI_ATTRIB_OPTIMAL_PBUFFER_WIDTH,        optimalPbufferWidth),
 492     __ATTRIB(__DRI_ATTRIB_OPTIMAL_PBUFFER_HEIGHT,       optimalPbufferHeight),
 493     __ATTRIB(__DRI_ATTRIB_SWAP_METHOD,                  swapMethod),
 494     __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGB,          bindToTextureRgb),
 495     __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGBA,         bindToTextureRgba),
 496     __ATTRIB(__DRI_ATTRIB_BIND_TO_MIPMAP_TEXTURE,       bindToMipmapTexture),
 497     __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_TARGETS,      bindToTextureTargets),
 498     __ATTRIB(__DRI_ATTRIB_YINVERTED,                    yInverted),
 499     __ATTRIB(__DRI_ATTRIB_FRAMEBUFFER_SRGB_CAPABLE,     sRGBCapable),
 500
 501     /* The struct field doesn't matter here, these are handled by the
 502      * switch in driGetConfigAttribIndex.  We need them in the array
 503      * so the iterator includes them though.*/
 504     __ATTRIB(__DRI_ATTRIB_RENDER_TYPE,                  level),
 505     __ATTRIB(__DRI_ATTRIB_CONFIG_CAVEAT,                level),
 506     __ATTRIB(__DRI_ATTRIB_SWAP_METHOD,                  level)
 507 };
 508
 509 #define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
 510
 511
 512 /**
 513  * Return the value of a configuration attribute.  The attribute is
 514  * indicated by the index.
 515  */
 516 static int
 517 driGetConfigAttribIndex(const __DRIconfig *config,
 518                         unsigned int index, unsigned int *value)
 519 {
 520     switch (attribMap[index].attrib) {
 521     case __DRI_ATTRIB_RENDER_TYPE:
 522         /* no support for color index mode */
 523         *value = __DRI_ATTRIB_RGBA_BIT;
 524         break;
 525     case __DRI_ATTRIB_CONFIG_CAVEAT:
 526         if (config->modes.visualRating == GLX_NON_CONFORMANT_CONFIG)
 527             *value = __DRI_ATTRIB_NON_CONFORMANT_CONFIG;
 528         else if (config->modes.visualRating == GLX_SLOW_CONFIG)
 529             *value = __DRI_ATTRIB_SLOW_BIT;
 530         else
 531             *value = 0;
 532         break;
 533     case __DRI_ATTRIB_SWAP_METHOD:
 534         /* XXX no return value??? */
 535         break;
 536
 537     case __DRI_ATTRIB_FLOAT_MODE:
 538         /* this field is not int-sized */
 539         *value = config->modes.floatMode;
 540         break;
 541
 542     default:
 543         /* any other int-sized field */
 544         *value = *(unsigned int *)
 545             ((char *) &config->modes + attribMap[index].offset);
 546
 547         break;
 548     }
 549
 550     return GL_TRUE;
 551 }
 552
 553
 554 /**
 555  * Get the value of a configuration attribute.
 556  * \param attrib  the attribute (one of the _DRI_ATTRIB_x tokens)
 557  * \param value  returns the attribute's value
 558  * \return 1 for success, 0 for failure
 559  */
 560 int
 561 driGetConfigAttrib(const __DRIconfig *config,
 562                    unsigned int attrib, unsigned int *value)
 563 {
 564     int i;
 565
 566     for (i = 0; i < ARRAY_SIZE(attribMap); i++)
 567         if (attribMap[i].attrib == attrib)
 568             return driGetConfigAttribIndex(config, i, value);
 569
 570     return GL_FALSE;
 571 }
 572
 573
 574 /**
 575  * Get a configuration attribute name and value, given an index.
 576  * \param index  which field of the __DRIconfig to query
 577  * \param attrib  returns the attribute name (one of the _DRI_ATTRIB_x tokens)
 578  * \param value  returns the attribute's value
 579  * \return 1 for success, 0 for failure
 580  */
 581 int
 582 driIndexConfigAttrib(const __DRIconfig *config, int index,
 583                      unsigned int *attrib, unsigned int *value)
 584 {
 585     if (index >= 0 && index < ARRAY_SIZE(attribMap)) {
 586         *attrib = attribMap[index].attrib;
 587         return driGetConfigAttribIndex(config, index, value);
 588     }
 589
 590     return GL_FALSE;
 591 }