aboutsummaryrefslogtreecommitdiffstats
path: root/src/lib/fake-quartz-cg.c
blob: 39fe1611a9cc2df925490043e0851ed3db2b1d8b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
/**
 * libgamma -- Display server abstraction layer for gamma ramp adjustments
 * Copyright (C) 2014  Mattias Andrée (maandree@member.fsf.org)
 * 
 * This library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef FAKE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
# error Compiling fake-quartz-cg.c without FAKE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
#endif

/* This file very sloppily translates Mac OS X Quartz calls to X RandR calls.
 * It should by no means be used, without additional modification, as a
 * part of a compatibility layer. The purpose of this file is only to make
 * it possible to test for logical errors in Max OS X specific code on
 * a GNU/Linux system under X. */


#include "fake-quartz-cg.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#ifndef HAVE_LIBGAMMA_METHOD_X_RANDR
/* Use dummy translation. */


/**
 * Get a list of all online displays on the system.
 * 
 * @param   max_size      The number of elements allocated for `displays_out`.
 * @param   displays_out  List ot fill with the ID for each online display on the system.
 * @param   count_out     Output parameter for the number of elements stored in `displays_out`.
 *                        if `displays_out` is too small to fit all display ID:s,
 *                        `*count_out` will be `max_size`.
 * @return                `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGGetOnlineDisplayList(uint32_t max_size,
			       CGDirectDisplayID* restrict displays_out, uint32_t* restrict count_out)
{
  /* Pretend that we have 2 CRTC:s */
  uint32_t i;
  for (i = 0; (i < max_size) && (i < 2); i++)
    displays_out[i] = (CGDirectDisplayID)i;
  *count_out = i;
  return kCGErrorSuccess;
}


/**
 * Set the gamma ramps for a display.
 * 
 * @param   display     The ID of the display.
 * @param   gamma_size  The number of stops in gamma ramps.
 * @param   red         The gamma ramp for the red channel.
 * @param   green       The gamma ramp for the green channel.
 * @param   blue        The gamma ramp for the blue channel.
 * @return              `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGSetDisplayTransferByTable(CGDirectDisplayID display, uint32_t gamma_size, const CGGammaValue* red,
				    const CGGammaValue* green, const CGGammaValue* blue)
{
  (void) display;
  (void) red;
  (void) green;
  (void) blue;
  
  /* We pretend that our gamma ramps are of size 256. */
  if (gamma_size != 256)
    {
      fprintf(stderr, "Gamma size should be 256.\n");
      abort();
    }
  return kCGErrorSuccess;
}


/**
 * Get the current gamma ramps for a display.
 * 
 * @param   display         The ID of the display.
 * @param   gamma_size      The number of stops you have allocated for the gamma ramps.
 * @param   red             Table allocated for the gamma ramp for the red channel.
 * @param   green           Table allocated for the gamma ramp for the green channel.
 * @param   blue            Table allocated for the gamma ramp for the blue channel.
 * @param   gamma_size_out  Output parameter for the actual number of stops in the gamma ramps.
 * @return                  `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGGetDisplayTransferByTable(CGDirectDisplayID display, uint32_t gamma_size,
				    CGGammaValue* restrict red, CGGammaValue* restrict green,
				    CGGammaValue* restrict blue, uint32_t* restrict gamma_size_out)
{
  long i;
  (void) display;
  
  /* We pretend that our gamma ramps are of size 256. */
  if (gamma_size != 256)
    {
      fprintf(stderr, "Gamma size should be 256.\n");
      abort();
    }
  
  /* We pretend that our gamma ramps are of size 256. */
  *gamma_size_out = 256;
  
  /* Pretend that our gamma ramps are identity mappings. */
  for (i = 0; i < 256; i++)
    red[i] = green[i] = blue[i] = (CGGammaValue)i / 255;
  
  return kCGErrorSuccess;
}


/**
 * Restore each display's gamma ramps to the settings in ColorSync.
 */
void CGDisplayRestoreColorSyncSettings(void)
{
  /* Do nothing. */
}


/**
 * Get the number of stops in the gamma ramps for a display.
 * 
 * @param   display  The ID of the display.
 * @return           The number of stops in the gamma ramps.
 */
uint32_t CGDisplayGammaTableCapacity(CGDirectDisplayID display)
{
  /* We pretend that our gamma ramps are of size 256. */
  (void) display;
  return 256;
}


/**
 * Release resources used by the backend.
 */
void close_fake_quartz(void)
{
  /* Do nothing. */
}


#else
/* Use translation to X RandR. */


#include <xcb/xcb.h>
#include <xcb/randr.h>



/**
 * Connection to the X RandR display.
 */
static xcb_connection_t* restrict connection = NULL;

/**
 * Resouces for the screen.
 * We only have one screen, again this is a very sloppy compatibility layer.
 */
static xcb_randr_get_screen_resources_current_reply_t* restrict res_reply = NULL;

/**
 * The number of available CRTC:s.
 */
static uint32_t crtc_count = 0;

/**
 * List of X RandR CRTC:s.
 */
static xcb_randr_crtc_t* restrict crtcs = NULL;

/**
 * The original gamma ramps, used to emulate gamma ramp restoration to system settings.
 */
static uint16_t* restrict original_ramps = NULL;



/* xcb violates the rule to never return struct:s. */
#ifdef __GCC__
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Waggregate-return"
#endif


/**
 * Get a list of all online displays on the system.
 * 
 * @param   max_size      The number of elements allocated for `displays_out`.
 * @param   displays_out  List ot fill with the ID for each online display on the system.
 * @param   count_out     Output parameter for the number of elements stored in `displays_out`.
 *                        if `displays_out` is too small to fit all display ID:s,
 *                        `*count_out` will be `max_size`.
 * @return                `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGGetOnlineDisplayList(uint32_t max_size,
			       CGDirectDisplayID* restrict displays_out, uint32_t* restrict count_out)
{
  uint32_t i;
  
  /* Connect to the display and get screen data if not already done so. */
  if (connection == NULL)
    {
      xcb_generic_error_t* error;
      xcb_screen_iterator_t iter;
      xcb_randr_get_screen_resources_current_cookie_t res_cookie;
      xcb_randr_get_crtc_gamma_cookie_t gamma_cookie;
      xcb_randr_get_crtc_gamma_reply_t* restrict gamma_reply;
      
      /* Connect to the display. */
      connection = xcb_connect(NULL, NULL);
      /* Get the first screen. */
      iter = xcb_setup_roots_iterator(xcb_get_setup(connection));
      /* Get the resources of the screen. */
      res_cookie = xcb_randr_get_screen_resources_current(connection, iter.data->root);
      res_reply = xcb_randr_get_screen_resources_current_reply(connection, res_cookie, &error);
      if (error)
	{
	  fprintf(stderr, "Failed to open X connection.\n");
	  xcb_disconnect(connection);
	  crtc_count = 0;
	  return ~kCGErrorSuccess;
	}
      
      /* Get the number of CRTC:s. */
      crtc_count = (uint32_t)(res_reply->num_crtcs);
      /* Get the CRTC ID:s. */
      crtcs = xcb_randr_get_screen_resources_current_crtcs(res_reply);
      
      /* Allocate memory where we store the
	 gamma ramps as they looked when this
	 adjustment method was first used.
	 This is used to emulate the functionality
	 of `CGDisplayRestoreColorSyncSettings`
	 which restore the all gamma ramps on
	 the system to the system settnigs.
      */
      original_ramps = malloc(crtc_count * 3 * 256 * sizeof(uint16_t));
      if (original_ramps == NULL)
	{
	  perror("malloc");
	  xcb_disconnect(connection);
	  crtc_count = 0;
	  return ~kCGErrorSuccess;
	}
      
      /* Fill the gamma ramps we just allocated. */
      for (i = 0; i < crtc_count; i++)
	{
	  /* Read current gamma ramps. */
	  gamma_cookie = xcb_randr_get_crtc_gamma(connection, crtcs[i]);
	  gamma_reply = xcb_randr_get_crtc_gamma_reply(connection, gamma_cookie, &error);
	  if (error)
	    {
	      fprintf(stderr, "Failed to read gamma ramps.\n");
	      xcb_disconnect(connection);
	      crtc_count = 0;
	      return ~kCGErrorSuccess;
	    }
	  
	  /* Copy over the gamma ramps to the memory area we have allocated. */
#define __DEST(C)  original_ramps + (C + 3 * i) * 256
#define __SRC(C)  xcb_randr_get_crtc_gamma_##C(gamma_reply)
	  memcpy(__DEST(0), __SRC(red),   256 * sizeof(uint16_t));
	  memcpy(__DEST(1), __SRC(green), 256 * sizeof(uint16_t));
	  memcpy(__DEST(2), __SRC(blue),  256 * sizeof(uint16_t));
#undef __SRC
#undef __DEST
	  
	  /* Release resouces. */
	  free(gamma_reply);
	}
    }
  
  /* Return CRTC ID:s. */
  for (i = 0; (i < max_size) && (i < crtc_count); i++)
    *(displays_out + i) = (CGDirectDisplayID)i;
  
  /* Return the number of CRTC ID:s we returned. */
  *count_out = i;
  return kCGErrorSuccess;
}


/**
 * Set the gamma ramps for a display.
 * 
 * @param   display     The ID of the display.
 * @param   gamma_size  The number of stops in gamma ramps.
 * @param   red         The gamma ramp for the red channel.
 * @param   green       The gamma ramp for the green channel.
 * @param   blue        The gamma ramp for the blue channel.
 * @return              `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGSetDisplayTransferByTable(CGDirectDisplayID display, uint32_t gamma_size, const CGGammaValue* red,
				    const CGGammaValue* green, const CGGammaValue* blue)
{
  xcb_void_cookie_t gamma_cookie;
  uint16_t r_int[256];
  uint16_t g_int[256];
  uint16_t b_int[256];
  long i;
  int32_t v;
  
  /* This is a sloppy compatibility layer that assumes the gamma ramp size is 256. */
  if (gamma_size != 256)
    {
      fprintf(stderr, "Gamma size should be 256.\n");
      abort();
    }
  
  /* Translate the gamma ramps from float (CoreGraphics) to 16-bit unsigned integer (X RandR). */
  for (i = 0; i < 256; i++)
    {
      /* Red channel. */
      v = (int32_t)(red[i] * UINT16_MAX);
      r_int[i] = (uint16_t)(v < 0 ? 0 : v > UINT16_MAX ? UINT16_MAX : v);
      
      /* Green channel. */
      v = (int32_t)(green[i] * UINT16_MAX);
      g_int[i] = (uint16_t)(v < 0 ? 0 : v > UINT16_MAX ? UINT16_MAX : v);
      
      /* Blue channel. */
      v = (int32_t)(blue[i] * UINT16_MAX);
      b_int[i] = (uint16_t)(v < 0 ? 0 : v > UINT16_MAX ? UINT16_MAX : v);
    }
  
  /* Apply gamma ramps. */
  gamma_cookie = xcb_randr_set_crtc_gamma_checked(connection, crtcs[display],
						  (uint16_t)gamma_size, r_int, g_int, b_int);
  /* Check for errors. */
  return xcb_request_check(connection, gamma_cookie) == NULL ? kCGErrorSuccess : ~kCGErrorSuccess;
}


/**
 * Get the current gamma ramps for a display.
 * 
 * @param   display         The ID of the display.
 * @param   gamma_size      The number of stops you have allocated for the gamma ramps.
 * @param   red             Table allocated for the gamma ramp for the red channel.
 * @param   green           Table allocated for the gamma ramp for the green channel.
 * @param   blue            Table allocated for the gamma ramp for the blue channel.
 * @param   gamma_size_out  Output parameter for the actual number of stops in the gamma ramps.
 * @return                  `kCGErrorSuccess` on success, and error number of failure.
 */
CGError CGGetDisplayTransferByTable(CGDirectDisplayID display, uint32_t gamma_size,
				    CGGammaValue* restrict red, CGGammaValue* restrict green,
				    CGGammaValue* restrict blue, uint32_t* restrict gamma_size_out)
{
  xcb_randr_get_crtc_gamma_cookie_t gamma_cookie;
  xcb_randr_get_crtc_gamma_reply_t* restrict gamma_reply;
  xcb_generic_error_t* error;
  uint16_t* restrict r_int;
  uint16_t* restrict g_int;
  uint16_t* restrict b_int;
  long i;
  
  /* This is a sloppy compatibility layer that assumes the gamma ramp size is 256. */
  if (gamma_size != 256)
    {
      fprintf(stderr, "Gamma size should be 256.\n");
      abort();
    }
  
  /* The gamma ramp size should be returned to the caller. */
  *gamma_size_out = 256;
  
  /* Read current gamma ramps. */
  gamma_cookie = xcb_randr_get_crtc_gamma(connection, crtcs[display]);
  gamma_reply = xcb_randr_get_crtc_gamma_reply(connection, gamma_cookie, &error);
  if (error)
    {
      fprintf(stderr, "Failed to write gamma ramps.\n");
      return ~kCGErrorSuccess;
    }
  
  /* Get gamma ramp values. */
  r_int = xcb_randr_get_crtc_gamma_red(gamma_reply);
  g_int = xcb_randr_get_crtc_gamma_green(gamma_reply);
  b_int = xcb_randr_get_crtc_gamma_blue(gamma_reply);
  
  /* Translate gamma ramps to float format,
     that is what CoreGraphics uses. */
  for (i = 0; i < 256; i++)
    {
      red[i]   = (CGGammaValue)(r_int[i]) / UINT16_MAX;
      green[i] = (CGGammaValue)(g_int[i]) / UINT16_MAX;
      blue[i]  = (CGGammaValue)(b_int[i]) / UINT16_MAX;
    }
  
  free(gamma_reply);
  return kCGErrorSuccess;
}


/**
 * Restore each display's gamma ramps to the settings in ColorSync.
 */
void CGDisplayRestoreColorSyncSettings(void)
{
  xcb_generic_error_t* error;
  xcb_void_cookie_t gamma_cookie;
  uint32_t i;
  
  /* Restore the gamma ramps on each monitor to
     the ramps that we used when we started. */
  for (i = 0; i < crtc_count; i++)
    {
      /* We assume that our gamma ramps are of the size
	 256 (this is a sloppy compatibility layer.) */
      gamma_cookie = xcb_randr_set_crtc_gamma_checked(connection, crtcs[i], 256,
						      original_ramps + (0 + 3 * i) * 256,
						      original_ramps + (1 + 3 * i) * 256,
						      original_ramps + (2 + 3 * i) * 256);
      if ((error = xcb_request_check(connection, gamma_cookie)))
	fprintf(stderr, "Quartz gamma reset emulation with RandR returned %i\n", error->error_code);
    }
}


/**
 * Get the number of stops in the gamma ramps for a display.
 * 
 * @param   display  The ID of the display.
 * @return           The number of stops in the gamma ramps.
 */
uint32_t CGDisplayGammaTableCapacity(CGDirectDisplayID display)
{
  /* We assume that our gamma ramps are of the size
     256 (this is a sloppy compatibility layer.) */
  (void) display;
  return 256;
}


#ifdef __GCC__
# pragma GCC diagnostic pop
#endif


/**
 * Release resources used by the backend.
 */
void close_fake_quartz_cg(void)
{
  free(res_reply), res_reply = NULL;
  if (connection != NULL)
    xcb_disconnect(connection), connection = NULL;
  free(original_ramps), original_ramps = NULL;
}

#endif