1 /**************************************************************************
2  *
3  * Copyright 2008 VMware, Inc.
4  * Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
5  * Copyright 2010-2011 LunarG, Inc.
6  * All Rights Reserved.
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a
9  * copy of this software and associated documentation files (the
10  * "Software"), to deal in the Software without restriction, including
11  * without limitation the rights to use, copy, modify, merge, publish,
12  * distribute, sub license, and/or sell copies of the Software, and to
13  * permit persons to whom the Software is furnished to do so, subject to
14  * the following conditions:
15  *
16  * The above copyright notice and this permission notice (including the
17  * next paragraph) shall be included in all copies or substantial portions
18  * of the Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26  * DEALINGS IN THE SOFTWARE.
27  *
28  **************************************************************************/
29 
30 
31 /**
32  * EGL Configuration (pixel format) functions.
33  */
34 
35 
36 #include <stdlib.h>
37 #include <string.h>
38 #include <assert.h>
39 #include "c99_compat.h"
40 #include "util/macros.h"
41 
42 #include "eglconfig.h"
43 #include "egldisplay.h"
44 #include "eglcurrent.h"
45 #include "egllog.h"
46 
47 
48 
49 
50 /**
51  * Init the given _EGLconfig to default values.
52  * \param id  the configuration's ID.
53  *
54  * Note that id must be positive for the config to be valid.
55  * It is also recommended that when there are N configs, their
56  * IDs are from 1 to N respectively.
57  */
58 void
_eglInitConfig(_EGLConfig * conf,_EGLDisplay * disp,EGLint id)59 _eglInitConfig(_EGLConfig *conf, _EGLDisplay *disp, EGLint id)
60 {
61    memset(conf, 0, sizeof(*conf));
62 
63    conf->Display = disp;
64 
65    /* some attributes take non-zero default values */
66    conf->ConfigID = id;
67    conf->ConfigCaveat = EGL_NONE;
68    conf->TransparentType = EGL_NONE;
69    conf->NativeVisualType = EGL_NONE;
70    conf->ColorBufferType = EGL_RGB_BUFFER;
71    conf->ComponentType = EGL_COLOR_COMPONENT_TYPE_FIXED_EXT;
72 }
73 
74 
75 /**
76  * Link a config to its display and return the handle of the link.
77  * The handle can be passed to client directly.
78  *
79  * Note that we just save the ptr to the config (we don't copy the config).
80  */
81 EGLConfig
_eglLinkConfig(_EGLConfig * conf)82 _eglLinkConfig(_EGLConfig *conf)
83 {
84    _EGLDisplay *disp = conf->Display;
85 
86    /* sanity check */
87    assert(disp);
88    assert(conf->ConfigID > 0);
89 
90    if (!disp->Configs) {
91       disp->Configs = _eglCreateArray("Config", 16);
92       if (!disp->Configs)
93          return (EGLConfig) NULL;
94    }
95 
96    _eglAppendArray(disp->Configs, (void *) conf);
97 
98    return (EGLConfig) conf;
99 }
100 
101 
102 /**
103  * Lookup a handle to find the linked config.
104  * Return NULL if the handle has no corresponding linked config.
105  */
106 _EGLConfig *
_eglLookupConfig(EGLConfig config,_EGLDisplay * disp)107 _eglLookupConfig(EGLConfig config, _EGLDisplay *disp)
108 {
109    _EGLConfig *conf;
110 
111    if (!disp)
112       return NULL;
113 
114    conf = (_EGLConfig *) _eglFindArray(disp->Configs, (void *) config);
115    if (conf)
116       assert(conf->Display == disp);
117 
118    return conf;
119 }
120 
121 
122 enum type {
123    ATTRIB_TYPE_INTEGER,
124    ATTRIB_TYPE_BOOLEAN,
125    ATTRIB_TYPE_BITMASK,
126    ATTRIB_TYPE_ENUM,
127    ATTRIB_TYPE_PSEUDO, /* non-queryable */
128    ATTRIB_TYPE_PLATFORM, /* platform-dependent */
129 };
130 
131 enum criterion {
132    ATTRIB_CRITERION_EXACT,
133    ATTRIB_CRITERION_ATLEAST,
134    ATTRIB_CRITERION_MASK,
135    ATTRIB_CRITERION_SPECIAL,
136    ATTRIB_CRITERION_IGNORE
137 };
138 
139 
140 /* EGL spec Table 3.1 and 3.4 */
141 static const struct {
142    EGLint attr;
143    enum type type;
144    enum criterion criterion;
145    EGLint default_value;
146 } _eglValidationTable[] =
147 {
148    /* core */
149    { EGL_BUFFER_SIZE,               ATTRIB_TYPE_INTEGER,
150                                     ATTRIB_CRITERION_ATLEAST,
151                                     0 },
152    { EGL_RED_SIZE,                  ATTRIB_TYPE_INTEGER,
153                                     ATTRIB_CRITERION_ATLEAST,
154                                     0 },
155    { EGL_GREEN_SIZE,                ATTRIB_TYPE_INTEGER,
156                                     ATTRIB_CRITERION_ATLEAST,
157                                     0 },
158    { EGL_BLUE_SIZE,                 ATTRIB_TYPE_INTEGER,
159                                     ATTRIB_CRITERION_ATLEAST,
160                                     0 },
161    { EGL_LUMINANCE_SIZE,            ATTRIB_TYPE_INTEGER,
162                                     ATTRIB_CRITERION_ATLEAST,
163                                     0 },
164    { EGL_ALPHA_SIZE,                ATTRIB_TYPE_INTEGER,
165                                     ATTRIB_CRITERION_ATLEAST,
166                                     0 },
167    { EGL_ALPHA_MASK_SIZE,           ATTRIB_TYPE_INTEGER,
168                                     ATTRIB_CRITERION_ATLEAST,
169                                     0 },
170    { EGL_BIND_TO_TEXTURE_RGB,       ATTRIB_TYPE_BOOLEAN,
171                                     ATTRIB_CRITERION_EXACT,
172                                     EGL_DONT_CARE },
173    { EGL_BIND_TO_TEXTURE_RGBA,      ATTRIB_TYPE_BOOLEAN,
174                                     ATTRIB_CRITERION_EXACT,
175                                     EGL_DONT_CARE },
176    { EGL_COLOR_BUFFER_TYPE,         ATTRIB_TYPE_ENUM,
177                                     ATTRIB_CRITERION_EXACT,
178                                     EGL_RGB_BUFFER },
179    { EGL_CONFIG_CAVEAT,             ATTRIB_TYPE_ENUM,
180                                     ATTRIB_CRITERION_EXACT,
181                                     EGL_DONT_CARE },
182    { EGL_CONFIG_ID,                 ATTRIB_TYPE_INTEGER,
183                                     ATTRIB_CRITERION_EXACT,
184                                     EGL_DONT_CARE },
185    { EGL_CONFORMANT,                ATTRIB_TYPE_BITMASK,
186                                     ATTRIB_CRITERION_MASK,
187                                     0 },
188    { EGL_DEPTH_SIZE,                ATTRIB_TYPE_INTEGER,
189                                     ATTRIB_CRITERION_ATLEAST,
190                                     0 },
191    { EGL_LEVEL,                     ATTRIB_TYPE_PLATFORM,
192                                     ATTRIB_CRITERION_EXACT,
193                                     0 },
194    { EGL_MAX_PBUFFER_WIDTH,         ATTRIB_TYPE_INTEGER,
195                                     ATTRIB_CRITERION_IGNORE,
196                                     0 },
197    { EGL_MAX_PBUFFER_HEIGHT,        ATTRIB_TYPE_INTEGER,
198                                     ATTRIB_CRITERION_IGNORE,
199                                     0 },
200    { EGL_MAX_PBUFFER_PIXELS,        ATTRIB_TYPE_INTEGER,
201                                     ATTRIB_CRITERION_IGNORE,
202                                     0 },
203    { EGL_MAX_SWAP_INTERVAL,         ATTRIB_TYPE_INTEGER,
204                                     ATTRIB_CRITERION_EXACT,
205                                     EGL_DONT_CARE },
206    { EGL_MIN_SWAP_INTERVAL,         ATTRIB_TYPE_INTEGER,
207                                     ATTRIB_CRITERION_EXACT,
208                                     EGL_DONT_CARE },
209    { EGL_NATIVE_RENDERABLE,         ATTRIB_TYPE_BOOLEAN,
210                                     ATTRIB_CRITERION_EXACT,
211                                     EGL_DONT_CARE },
212    { EGL_NATIVE_VISUAL_ID,          ATTRIB_TYPE_PLATFORM,
213                                     ATTRIB_CRITERION_IGNORE,
214                                     0 },
215    { EGL_NATIVE_VISUAL_TYPE,        ATTRIB_TYPE_PLATFORM,
216                                     ATTRIB_CRITERION_EXACT,
217                                     EGL_DONT_CARE },
218    { EGL_RENDERABLE_TYPE,           ATTRIB_TYPE_BITMASK,
219                                     ATTRIB_CRITERION_MASK,
220                                     EGL_OPENGL_ES_BIT },
221    { EGL_SAMPLE_BUFFERS,            ATTRIB_TYPE_INTEGER,
222                                     ATTRIB_CRITERION_ATLEAST,
223                                     0 },
224    { EGL_SAMPLES,                   ATTRIB_TYPE_INTEGER,
225                                     ATTRIB_CRITERION_ATLEAST,
226                                     0 },
227    { EGL_STENCIL_SIZE,              ATTRIB_TYPE_INTEGER,
228                                     ATTRIB_CRITERION_ATLEAST,
229                                     0 },
230    { EGL_SURFACE_TYPE,              ATTRIB_TYPE_BITMASK,
231                                     ATTRIB_CRITERION_MASK,
232                                     EGL_WINDOW_BIT },
233    { EGL_TRANSPARENT_TYPE,          ATTRIB_TYPE_ENUM,
234                                     ATTRIB_CRITERION_EXACT,
235                                     EGL_NONE },
236    { EGL_TRANSPARENT_RED_VALUE,     ATTRIB_TYPE_INTEGER,
237                                     ATTRIB_CRITERION_EXACT,
238                                     EGL_DONT_CARE },
239    { EGL_TRANSPARENT_GREEN_VALUE,   ATTRIB_TYPE_INTEGER,
240                                     ATTRIB_CRITERION_EXACT,
241                                     EGL_DONT_CARE },
242    { EGL_TRANSPARENT_BLUE_VALUE,    ATTRIB_TYPE_INTEGER,
243                                     ATTRIB_CRITERION_EXACT,
244                                     EGL_DONT_CARE },
245    { EGL_MATCH_NATIVE_PIXMAP,       ATTRIB_TYPE_PSEUDO,
246                                     ATTRIB_CRITERION_SPECIAL,
247                                     EGL_NONE },
248    /* extensions */
249    { EGL_Y_INVERTED_NOK,            ATTRIB_TYPE_BOOLEAN,
250                                     ATTRIB_CRITERION_EXACT,
251                                     EGL_DONT_CARE },
252    { EGL_FRAMEBUFFER_TARGET_ANDROID, ATTRIB_TYPE_BOOLEAN,
253                                     ATTRIB_CRITERION_EXACT,
254                                     EGL_DONT_CARE },
255    { EGL_RECORDABLE_ANDROID,        ATTRIB_TYPE_BOOLEAN,
256                                     ATTRIB_CRITERION_EXACT,
257                                     EGL_DONT_CARE },
258    { EGL_COLOR_COMPONENT_TYPE_EXT,  ATTRIB_TYPE_ENUM,
259                                     ATTRIB_CRITERION_EXACT,
260                                     EGL_COLOR_COMPONENT_TYPE_FIXED_EXT },
261 };
262 
263 
264 /**
265  * Return true if a config is valid.  When for_matching is true,
266  * EGL_DONT_CARE is accepted as a valid attribute value, and checks
267  * for conflicting attribute values are skipped.
268  *
269  * Note that some attributes are platform-dependent and are not
270  * checked.
271  */
272 EGLBoolean
_eglValidateConfig(const _EGLConfig * conf,EGLBoolean for_matching)273 _eglValidateConfig(const _EGLConfig *conf, EGLBoolean for_matching)
274 {
275    _EGLDisplay *disp = conf->Display;
276    EGLint i, attr, val;
277    EGLBoolean valid = EGL_TRUE;
278 
279    /* check attributes by their types */
280    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
281       EGLint mask;
282 
283       attr = _eglValidationTable[i].attr;
284       val = _eglGetConfigKey(conf, attr);
285 
286       switch (_eglValidationTable[i].type) {
287       case ATTRIB_TYPE_INTEGER:
288          switch (attr) {
289          case EGL_CONFIG_ID:
290             /* config id must be positive */
291             if (val <= 0)
292                valid = EGL_FALSE;
293             break;
294          case EGL_SAMPLE_BUFFERS:
295             /* there can be at most 1 sample buffer */
296             if (val > 1 || val < 0)
297                valid = EGL_FALSE;
298             break;
299          default:
300             if (val < 0)
301                valid = EGL_FALSE;
302             break;
303          }
304          break;
305       case ATTRIB_TYPE_BOOLEAN:
306          if (val != EGL_TRUE && val != EGL_FALSE)
307             valid = EGL_FALSE;
308          break;
309       case ATTRIB_TYPE_ENUM:
310          switch (attr) {
311          case EGL_CONFIG_CAVEAT:
312             if (val != EGL_NONE && val != EGL_SLOW_CONFIG &&
313                 val != EGL_NON_CONFORMANT_CONFIG)
314                valid = EGL_FALSE;
315             break;
316          case EGL_TRANSPARENT_TYPE:
317             if (val != EGL_NONE && val != EGL_TRANSPARENT_RGB)
318                valid = EGL_FALSE;
319             break;
320          case EGL_COLOR_BUFFER_TYPE:
321             if (val != EGL_RGB_BUFFER && val != EGL_LUMINANCE_BUFFER)
322                valid = EGL_FALSE;
323             break;
324          case EGL_COLOR_COMPONENT_TYPE_EXT:
325             if (val != EGL_COLOR_COMPONENT_TYPE_FIXED_EXT &&
326                 val != EGL_COLOR_COMPONENT_TYPE_FLOAT_EXT)
327                valid = EGL_FALSE;
328             break;
329          default:
330             unreachable("check _eglValidationTable[]");
331             break;
332          }
333          break;
334       case ATTRIB_TYPE_BITMASK:
335          switch (attr) {
336          case EGL_SURFACE_TYPE:
337             mask = EGL_PBUFFER_BIT |
338                    EGL_PIXMAP_BIT |
339                    EGL_WINDOW_BIT |
340                    EGL_VG_COLORSPACE_LINEAR_BIT |
341                    EGL_VG_ALPHA_FORMAT_PRE_BIT |
342                    EGL_MULTISAMPLE_RESOLVE_BOX_BIT |
343                    EGL_SWAP_BEHAVIOR_PRESERVED_BIT;
344             if (disp->Extensions.KHR_mutable_render_buffer)
345                mask |= EGL_MUTABLE_RENDER_BUFFER_BIT_KHR;
346             break;
347          case EGL_RENDERABLE_TYPE:
348          case EGL_CONFORMANT:
349             mask = EGL_OPENGL_ES_BIT |
350                    EGL_OPENVG_BIT |
351                    EGL_OPENGL_ES2_BIT |
352                    EGL_OPENGL_ES3_BIT_KHR |
353                    EGL_OPENGL_BIT;
354             break;
355          default:
356             unreachable("check _eglValidationTable[]");
357             mask = 0;
358             break;
359          }
360          if (val & ~mask)
361             valid = EGL_FALSE;
362          break;
363       case ATTRIB_TYPE_PLATFORM:
364          /* unable to check platform-dependent attributes here */
365          break;
366       case ATTRIB_TYPE_PSEUDO:
367          /* pseudo attributes should not be set */
368          if (val != 0)
369             valid = EGL_FALSE;
370          break;
371       }
372 
373       if (!valid && for_matching) {
374          /* accept EGL_DONT_CARE as a valid value */
375          if (val == EGL_DONT_CARE)
376             valid = EGL_TRUE;
377          if (_eglValidationTable[i].criterion == ATTRIB_CRITERION_SPECIAL)
378             valid = EGL_TRUE;
379       }
380       if (!valid) {
381          _eglLog(_EGL_DEBUG,
382                "attribute 0x%04x has an invalid value 0x%x", attr, val);
383          break;
384       }
385    }
386 
387    /* any invalid attribute value should have been catched */
388    if (!valid || for_matching)
389       return valid;
390 
391    /* now check for conflicting attribute values */
392 
393    switch (conf->ColorBufferType) {
394    case EGL_RGB_BUFFER:
395       if (conf->LuminanceSize)
396          valid = EGL_FALSE;
397       if (conf->RedSize + conf->GreenSize +
398             conf->BlueSize + conf->AlphaSize != conf->BufferSize)
399          valid = EGL_FALSE;
400       break;
401    case EGL_LUMINANCE_BUFFER:
402       if (conf->RedSize || conf->GreenSize || conf->BlueSize)
403          valid = EGL_FALSE;
404       if (conf->LuminanceSize + conf->AlphaSize != conf->BufferSize)
405          valid = EGL_FALSE;
406       break;
407    }
408    if (!valid) {
409       _eglLog(_EGL_DEBUG, "conflicting color buffer type and channel sizes");
410       return EGL_FALSE;
411    }
412 
413    if (!conf->SampleBuffers && conf->Samples)
414       valid = EGL_FALSE;
415    if (!valid) {
416       _eglLog(_EGL_DEBUG, "conflicting samples and sample buffers");
417       return EGL_FALSE;
418    }
419 
420    if (!(conf->SurfaceType & EGL_WINDOW_BIT)) {
421       if (conf->NativeVisualID != 0 || conf->NativeVisualType != EGL_NONE)
422          valid = EGL_FALSE;
423    }
424    if (!(conf->SurfaceType & EGL_PBUFFER_BIT)) {
425       if (conf->BindToTextureRGB || conf->BindToTextureRGBA)
426          valid = EGL_FALSE;
427    }
428    if (!valid) {
429       _eglLog(_EGL_DEBUG, "conflicting surface type and native visual/texture binding");
430       return EGL_FALSE;
431    }
432 
433    return valid;
434 }
435 
436 
437 /**
438  * Return true if a config matches the criteria.  This and
439  * _eglParseConfigAttribList together implement the algorithm
440  * described in "Selection of EGLConfigs".
441  *
442  * Note that attributes that are special (currently, only
443  * EGL_MATCH_NATIVE_PIXMAP) are ignored.
444  */
445 EGLBoolean
_eglMatchConfig(const _EGLConfig * conf,const _EGLConfig * criteria)446 _eglMatchConfig(const _EGLConfig *conf, const _EGLConfig *criteria)
447 {
448    EGLint attr, val, i;
449    EGLBoolean matched = EGL_TRUE;
450 
451    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
452       EGLint cmp;
453       if (_eglValidationTable[i].criterion == ATTRIB_CRITERION_IGNORE)
454          continue;
455 
456       attr = _eglValidationTable[i].attr;
457       cmp = _eglGetConfigKey(criteria, attr);
458       if (cmp == EGL_DONT_CARE)
459          continue;
460 
461       val = _eglGetConfigKey(conf, attr);
462       switch (_eglValidationTable[i].criterion) {
463       case ATTRIB_CRITERION_EXACT:
464          if (val != cmp)
465             matched = EGL_FALSE;
466          break;
467       case ATTRIB_CRITERION_ATLEAST:
468          if (val < cmp)
469             matched = EGL_FALSE;
470          break;
471       case ATTRIB_CRITERION_MASK:
472          if ((val & cmp) != cmp)
473             matched = EGL_FALSE;
474          break;
475       case ATTRIB_CRITERION_SPECIAL:
476          /* ignored here */
477          break;
478       case ATTRIB_CRITERION_IGNORE:
479          unreachable("already handled above");
480          break;
481       }
482 
483       if (!matched) {
484 #ifndef DEBUG
485          /* only print the common errors when DEBUG is not defined */
486          if (attr != EGL_RENDERABLE_TYPE)
487             break;
488 #endif
489          _eglLog(_EGL_DEBUG,
490                "the value (0x%x) of attribute 0x%04x did not meet the criteria (0x%x)",
491                val, attr, cmp);
492          break;
493       }
494    }
495 
496    return matched;
497 }
498 
499 static inline EGLBoolean
_eglIsConfigAttribValid(_EGLConfig * conf,EGLint attr)500 _eglIsConfigAttribValid(_EGLConfig *conf, EGLint attr)
501 {
502    if (_eglOffsetOfConfig(attr) < 0)
503       return EGL_FALSE;
504 
505    switch (attr) {
506    case EGL_Y_INVERTED_NOK:
507       return conf->Display->Extensions.NOK_texture_from_pixmap;
508    case EGL_FRAMEBUFFER_TARGET_ANDROID:
509       return conf->Display->Extensions.ANDROID_framebuffer_target;
510    case EGL_RECORDABLE_ANDROID:
511       return conf->Display->Extensions.ANDROID_recordable;
512    default:
513       break;
514    }
515 
516    return EGL_TRUE;
517 }
518 
519 /**
520  * Initialize a criteria config from the given attribute list.
521  * Return EGL_FALSE if any of the attribute is invalid.
522  */
523 EGLBoolean
_eglParseConfigAttribList(_EGLConfig * conf,_EGLDisplay * disp,const EGLint * attrib_list)524 _eglParseConfigAttribList(_EGLConfig *conf, _EGLDisplay *disp,
525                           const EGLint *attrib_list)
526 {
527    EGLint attr, val, i;
528 
529    _eglInitConfig(conf, disp, EGL_DONT_CARE);
530 
531    /* reset to default values */
532    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
533       attr = _eglValidationTable[i].attr;
534       val = _eglValidationTable[i].default_value;
535       _eglSetConfigKey(conf, attr, val);
536    }
537 
538    /* parse the list */
539    for (i = 0; attrib_list && attrib_list[i] != EGL_NONE; i += 2) {
540       attr = attrib_list[i];
541       val = attrib_list[i + 1];
542 
543       if (!_eglIsConfigAttribValid(conf, attr))
544          return EGL_FALSE;
545 
546       _eglSetConfigKey(conf, attr, val);
547    }
548 
549    if (!_eglValidateConfig(conf, EGL_TRUE))
550       return EGL_FALSE;
551 
552    /* EGL_LEVEL and EGL_MATCH_NATIVE_PIXMAP cannot be EGL_DONT_CARE */
553    if (conf->Level == EGL_DONT_CARE ||
554        conf->MatchNativePixmap == EGL_DONT_CARE)
555       return EGL_FALSE;
556 
557    /* ignore other attributes when EGL_CONFIG_ID is given */
558    if (conf->ConfigID != EGL_DONT_CARE) {
559       for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
560          attr = _eglValidationTable[i].attr;
561          if (attr != EGL_CONFIG_ID)
562             _eglSetConfigKey(conf, attr, EGL_DONT_CARE);
563       }
564    }
565    else {
566       if (!(conf->SurfaceType & EGL_WINDOW_BIT))
567          conf->NativeVisualType = EGL_DONT_CARE;
568 
569       if (conf->TransparentType == EGL_NONE) {
570          conf->TransparentRedValue = EGL_DONT_CARE;
571          conf->TransparentGreenValue = EGL_DONT_CARE;
572          conf->TransparentBlueValue = EGL_DONT_CARE;
573       }
574    }
575 
576    return EGL_TRUE;
577 }
578 
579 
580 /**
581  * Decide the ordering of conf1 and conf2, under the given criteria.
582  * When compare_id is true, this implements the algorithm described
583  * in "Sorting of EGLConfigs".  When compare_id is false,
584  * EGL_CONFIG_ID is not compared.
585  *
586  * It returns a negative integer if conf1 is considered to come
587  * before conf2;  a positive integer if conf2 is considered to come
588  * before conf1;  zero if the ordering cannot be decided.
589  *
590  * Note that EGL_NATIVE_VISUAL_TYPE is platform-dependent and is
591  * ignored here.
592  */
593 EGLint
_eglCompareConfigs(const _EGLConfig * conf1,const _EGLConfig * conf2,const _EGLConfig * criteria,EGLBoolean compare_id)594 _eglCompareConfigs(const _EGLConfig *conf1, const _EGLConfig *conf2,
595                    const _EGLConfig *criteria, EGLBoolean compare_id)
596 {
597    const EGLint compare_attribs[] = {
598       EGL_BUFFER_SIZE,
599       EGL_SAMPLE_BUFFERS,
600       EGL_SAMPLES,
601       EGL_DEPTH_SIZE,
602       EGL_STENCIL_SIZE,
603       EGL_ALPHA_MASK_SIZE,
604    };
605    EGLint val1, val2;
606    EGLint i;
607 
608    if (conf1 == conf2)
609       return 0;
610 
611    /* the enum values have the desired ordering */
612    STATIC_ASSERT(EGL_NONE < EGL_SLOW_CONFIG);
613    STATIC_ASSERT(EGL_SLOW_CONFIG < EGL_NON_CONFORMANT_CONFIG);
614    val1 = conf1->ConfigCaveat - conf2->ConfigCaveat;
615    if (val1)
616       return val1;
617 
618    /* the enum values have the desired ordering */
619    STATIC_ASSERT(EGL_RGB_BUFFER < EGL_LUMINANCE_BUFFER);
620    val1 = conf1->ColorBufferType - conf2->ColorBufferType;
621    if (val1)
622       return val1;
623 
624    if (criteria) {
625       val1 = val2 = 0;
626       if (conf1->ColorBufferType == EGL_RGB_BUFFER) {
627          if (criteria->RedSize > 0) {
628             val1 += conf1->RedSize;
629             val2 += conf2->RedSize;
630          }
631          if (criteria->GreenSize > 0) {
632             val1 += conf1->GreenSize;
633             val2 += conf2->GreenSize;
634          }
635          if (criteria->BlueSize > 0) {
636             val1 += conf1->BlueSize;
637             val2 += conf2->BlueSize;
638          }
639       }
640       else {
641          if (criteria->LuminanceSize > 0) {
642             val1 += conf1->LuminanceSize;
643             val2 += conf2->LuminanceSize;
644          }
645       }
646       if (criteria->AlphaSize > 0) {
647          val1 += conf1->AlphaSize;
648          val2 += conf2->AlphaSize;
649       }
650    }
651    else {
652       /* assume the default criteria, which gives no specific ordering */
653       val1 = val2 = 0;
654    }
655 
656    /* for color bits, larger one is preferred */
657    if (val1 != val2)
658       return (val2 - val1);
659 
660    for (i = 0; i < ARRAY_SIZE(compare_attribs); i++) {
661       val1 = _eglGetConfigKey(conf1, compare_attribs[i]);
662       val2 = _eglGetConfigKey(conf2, compare_attribs[i]);
663       if (val1 != val2)
664          return (val1 - val2);
665    }
666 
667    /* EGL_NATIVE_VISUAL_TYPE cannot be compared here */
668 
669    return (compare_id) ? (conf1->ConfigID - conf2->ConfigID) : 0;
670 }
671 
672 
673 static inline
_eglSwapConfigs(const _EGLConfig ** conf1,const _EGLConfig ** conf2)674 void _eglSwapConfigs(const _EGLConfig **conf1, const _EGLConfig **conf2)
675 {
676    const _EGLConfig *tmp = *conf1;
677    *conf1 = *conf2;
678    *conf2 = tmp;
679 }
680 
681 
682 /**
683  * Quick sort an array of configs.  This differs from the standard
684  * qsort() in that the compare function accepts an additional
685  * argument.
686  */
687 static void
_eglSortConfigs(const _EGLConfig ** configs,EGLint count,EGLint (* compare)(const _EGLConfig *,const _EGLConfig *,void *),void * priv_data)688 _eglSortConfigs(const _EGLConfig **configs, EGLint count,
689                 EGLint (*compare)(const _EGLConfig *, const _EGLConfig *,
690                                   void *),
691                 void *priv_data)
692 {
693    const EGLint pivot = 0;
694    EGLint i, j;
695 
696    if (count <= 1)
697       return;
698 
699    _eglSwapConfigs(&configs[pivot], &configs[count / 2]);
700    i = 1;
701    j = count - 1;
702    do {
703       while (i < count && compare(configs[i], configs[pivot], priv_data) < 0)
704          i++;
705       while (compare(configs[j], configs[pivot], priv_data) > 0)
706          j--;
707       if (i < j) {
708          _eglSwapConfigs(&configs[i], &configs[j]);
709          i++;
710          j--;
711       }
712       else if (i == j) {
713          i++;
714          j--;
715          break;
716       }
717    } while (i <= j);
718    _eglSwapConfigs(&configs[pivot], &configs[j]);
719 
720    _eglSortConfigs(configs, j, compare, priv_data);
721    _eglSortConfigs(configs + i, count - i, compare, priv_data);
722 }
723 
724 
725 /**
726  * A helper function for implementing eglChooseConfig.  See _eglFilterArray and
727  * _eglSortConfigs for the meanings of match and compare.
728  */
729 EGLBoolean
_eglFilterConfigArray(_EGLArray * array,EGLConfig * configs,EGLint config_size,EGLint * num_configs,EGLBoolean (* match)(const _EGLConfig *,void *),EGLint (* compare)(const _EGLConfig *,const _EGLConfig *,void *),void * priv_data)730 _eglFilterConfigArray(_EGLArray *array, EGLConfig *configs,
731                       EGLint config_size, EGLint *num_configs,
732                       EGLBoolean (*match)(const _EGLConfig *, void *),
733                       EGLint (*compare)(const _EGLConfig *, const _EGLConfig *,
734                                         void *),
735                       void *priv_data)
736 {
737    _EGLConfig **configList;
738    EGLint i, count;
739 
740    /* get the number of matched configs */
741    count = _eglFilterArray(array, NULL, 0,
742          (_EGLArrayForEach) match, priv_data);
743    if (!count) {
744       *num_configs = count;
745       return EGL_TRUE;
746    }
747 
748    configList = malloc(sizeof(*configList) * count);
749    if (!configList)
750       return _eglError(EGL_BAD_ALLOC, "eglChooseConfig(out of memory)");
751 
752    /* get the matched configs */
753    _eglFilterArray(array, (void **) configList, count,
754          (_EGLArrayForEach) match, priv_data);
755 
756    /* perform sorting of configs */
757    if (configs && count) {
758       _eglSortConfigs((const _EGLConfig **) configList, count,
759                       compare, priv_data);
760       count = MIN2(count, config_size);
761       for (i = 0; i < count; i++)
762          configs[i] = _eglGetConfigHandle(configList[i]);
763    }
764 
765    free(configList);
766 
767    *num_configs = count;
768 
769    return EGL_TRUE;
770 }
771 
772 
773 static EGLBoolean
_eglFallbackMatch(const _EGLConfig * conf,void * priv_data)774 _eglFallbackMatch(const _EGLConfig *conf, void *priv_data)
775 {
776    return _eglMatchConfig(conf, (const _EGLConfig *) priv_data);
777 }
778 
779 
780 static EGLint
_eglFallbackCompare(const _EGLConfig * conf1,const _EGLConfig * conf2,void * priv_data)781 _eglFallbackCompare(const _EGLConfig *conf1, const _EGLConfig *conf2,
782                     void *priv_data)
783 {
784    return _eglCompareConfigs(conf1, conf2,
785          (const _EGLConfig *) priv_data, EGL_TRUE);
786 }
787 
788 
789 /**
790  * Typical fallback routine for eglChooseConfig
791  */
792 EGLBoolean
_eglChooseConfig(_EGLDisplay * disp,const EGLint * attrib_list,EGLConfig * configs,EGLint config_size,EGLint * num_configs)793 _eglChooseConfig(_EGLDisplay *disp, const EGLint *attrib_list,
794                  EGLConfig *configs, EGLint config_size, EGLint *num_configs)
795 {
796    _EGLConfig criteria;
797 
798    if (!_eglParseConfigAttribList(&criteria, disp, attrib_list))
799       return _eglError(EGL_BAD_ATTRIBUTE, "eglChooseConfig");
800 
801    return _eglFilterConfigArray(disp->Configs,
802          configs, config_size, num_configs,
803          _eglFallbackMatch, _eglFallbackCompare,
804          (void *) &criteria);
805 }
806 
807 
808 /**
809  * Fallback for eglGetConfigAttrib.
810  */
811 EGLBoolean
_eglGetConfigAttrib(_EGLDisplay * disp,_EGLConfig * conf,EGLint attribute,EGLint * value)812 _eglGetConfigAttrib(_EGLDisplay *disp, _EGLConfig *conf,
813                     EGLint attribute, EGLint *value)
814 {
815    if (!_eglIsConfigAttribValid(conf, attribute))
816       return _eglError(EGL_BAD_ATTRIBUTE, "eglGetConfigAttrib");
817 
818    /* nonqueryable attributes */
819    switch (attribute) {
820    case EGL_MATCH_NATIVE_PIXMAP:
821       return _eglError(EGL_BAD_ATTRIBUTE, "eglGetConfigAttrib");
822       break;
823    default:
824       break;
825    }
826 
827    if (!value)
828       return _eglError(EGL_BAD_PARAMETER, "eglGetConfigAttrib");
829 
830    *value = _eglGetConfigKey(conf, attribute);
831    return EGL_TRUE;
832 }
833 
834 
835 static EGLBoolean
_eglFlattenConfig(void * elem,void * buffer)836 _eglFlattenConfig(void *elem, void *buffer)
837 {
838    _EGLConfig *conf = (_EGLConfig *) elem;
839    EGLConfig *handle = (EGLConfig *) buffer;
840    *handle = _eglGetConfigHandle(conf);
841    return EGL_TRUE;
842 }
843 
844 /**
845  * Fallback for eglGetConfigs.
846  */
847 EGLBoolean
_eglGetConfigs(_EGLDisplay * disp,EGLConfig * configs,EGLint config_size,EGLint * num_config)848 _eglGetConfigs(_EGLDisplay *disp, EGLConfig *configs,
849                EGLint config_size, EGLint *num_config)
850 {
851    *num_config = _eglFlattenArray(disp->Configs, (void *) configs,
852          sizeof(configs[0]), config_size, _eglFlattenConfig);
853 
854    return EGL_TRUE;
855 }
856