File: zone.c

package info (click to toggle)
darkplaces 0~20180412~beta1-2
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 18,200 kB
  • sloc: ansic: 176,886; makefile: 485; pascal: 455; perl: 372; objc: 245; sh: 102
file content (988 lines) | stat: -rw-r--r-- 30,815 bytes parent folder | download | duplicates (2)
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
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
/*
Copyright (C) 1996-1997 Id Software, Inc.

This program 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 2
of the License, or (at your option) any later version.

This program 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 program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// Z_zone.c

#include "quakedef.h"
#include "thread.h"

#ifdef WIN32
#include <windows.h>
#include <winbase.h>
#else
#include <unistd.h>
#endif

#ifdef _MSC_VER
#include <vadefs.h>
#else
#include <stdint.h>
#endif
#define MEMHEADER_SENTINEL_FOR_ADDRESS(p) ((sentinel_seed ^ (unsigned int) (uintptr_t) (p)) + sentinel_seed)
unsigned int sentinel_seed;

qboolean mem_bigendian = false;
void *mem_mutex = NULL;

// divVerent: enables file backed malloc using mmap to conserve swap space (instead of malloc)
#ifndef FILE_BACKED_MALLOC
# define FILE_BACKED_MALLOC 0
#endif

// LordHavoc: enables our own low-level allocator (instead of malloc)
#ifndef MEMCLUMPING
# define MEMCLUMPING 0
#endif
#ifndef MEMCLUMPING_FREECLUMPS
# define MEMCLUMPING_FREECLUMPS 0
#endif

#if MEMCLUMPING
// smallest unit we care about is this many bytes
#define MEMUNIT 128
// try to do 32MB clumps, but overhead eats into this
#ifndef MEMWANTCLUMPSIZE
# define MEMWANTCLUMPSIZE (1<<27)
#endif
// give malloc padding so we can't waste most of a page at the end
#define MEMCLUMPSIZE (MEMWANTCLUMPSIZE - MEMWANTCLUMPSIZE/MEMUNIT/32 - 128)
#define MEMBITS (MEMCLUMPSIZE / MEMUNIT)
#define MEMBITINTS (MEMBITS / 32)

typedef struct memclump_s
{
	// contents of the clump
	unsigned char block[MEMCLUMPSIZE];
	// should always be MEMCLUMP_SENTINEL
	unsigned int sentinel1;
	// if a bit is on, it means that the MEMUNIT bytes it represents are
	// allocated, otherwise free
	unsigned int bits[MEMBITINTS];
	// should always be MEMCLUMP_SENTINEL
	unsigned int sentinel2;
	// if this drops to 0, the clump is freed
	size_t blocksinuse;
	// largest block of memory available (this is reset to an optimistic
	// number when anything is freed, and updated when alloc fails the clump)
	size_t largestavailable;
	// next clump in the chain
	struct memclump_s *chain;
}
memclump_t;

#if MEMCLUMPING == 2
static memclump_t masterclump;
#endif
static memclump_t *clumpchain = NULL;
#endif


cvar_t developer_memory = {0, "developer_memory", "0", "prints debugging information about memory allocations"};
cvar_t developer_memorydebug = {0, "developer_memorydebug", "0", "enables memory corruption checks (very slow)"};
cvar_t developer_memoryreportlargerthanmb = {0, "developer_memorylargerthanmb", "16", "prints debugging information about memory allocations over this size"};
cvar_t sys_memsize_physical = {CVAR_READONLY, "sys_memsize_physical", "", "physical memory size in MB (or empty if unknown)"};
cvar_t sys_memsize_virtual = {CVAR_READONLY, "sys_memsize_virtual", "", "virtual memory size in MB (or empty if unknown)"};

static mempool_t *poolchain = NULL;

void Mem_PrintStats(void);
void Mem_PrintList(size_t minallocationsize);

#if FILE_BACKED_MALLOC
#include <stdlib.h>
#include <sys/mman.h>
typedef struct mmap_data_s
{
	size_t len;
}
mmap_data_t;
static void *mmap_malloc(size_t size)
{
	char vabuf[MAX_OSPATH + 1];
	char *tmpdir = getenv("TEMP");
	mmap_data_t *data;
	int fd;
	size += sizeof(mmap_data_t); // waste block
	dpsnprintf(vabuf, sizeof(vabuf), "%s/darkplaces.XXXXXX", tmpdir ? tmpdir : "/tmp");
	fd = mkstemp(vabuf);
	if(fd < 0)
		return NULL;
	ftruncate(fd, size);
	data = (unsigned char *) mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_NORESERVE, fd, 0);
	close(fd);
	unlink(vabuf);
	if(!data)
		return NULL;
	data->len = size;
	return (void *) (data + 1);
}
static void mmap_free(void *mem)
{
	mmap_data_t *data;
	if(!mem)
		return;
	data = ((mmap_data_t *) mem) - 1;
	munmap(data, data->len);
}
#define malloc mmap_malloc
#define free mmap_free
#endif

#if MEMCLUMPING != 2
// some platforms have a malloc that returns NULL but succeeds later
// (Windows growing its swapfile for example)
static void *attempt_malloc(size_t size)
{
	void *base;
	// try for half a second or so
	unsigned int attempts = 500;
	while (attempts--)
	{
		base = (void *)malloc(size);
		if (base)
			return base;
		Sys_Sleep(1000);
	}
	return NULL;
}
#endif

#if MEMCLUMPING
static memclump_t *Clump_NewClump(void)
{
	memclump_t **clumpchainpointer;
	memclump_t *clump;
#if MEMCLUMPING == 2
	if (clumpchain)
		return NULL;
	clump = &masterclump;
#else
	clump = (memclump_t*)attempt_malloc(sizeof(memclump_t));
	if (!clump)
		return NULL;
#endif

	// initialize clump
	if (developer_memorydebug.integer)
		memset(clump, 0xEF, sizeof(*clump));
	clump->sentinel1 = MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel1);
	memset(clump->bits, 0, sizeof(clump->bits));
	clump->sentinel2 = MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel2);
	clump->blocksinuse = 0;
	clump->largestavailable = 0;
	clump->chain = NULL;

	// link clump into chain
	for (clumpchainpointer = &clumpchain;*clumpchainpointer;clumpchainpointer = &(*clumpchainpointer)->chain)
		;
	*clumpchainpointer = clump;

	return clump;
}
#endif

// low level clumping functions, all other memory functions use these
static void *Clump_AllocBlock(size_t size)
{
	unsigned char *base;
#if MEMCLUMPING
	if (size <= MEMCLUMPSIZE)
	{
		int index;
		unsigned int bit;
		unsigned int needbits;
		unsigned int startbit;
		unsigned int endbit;
		unsigned int needints;
		int startindex;
		int endindex;
		unsigned int value;
		unsigned int mask;
		unsigned int *array;
		memclump_t **clumpchainpointer;
		memclump_t *clump;
		needbits = (size + MEMUNIT - 1) / MEMUNIT;
		needints = (needbits+31)>>5;
		for (clumpchainpointer = &clumpchain;;clumpchainpointer = &(*clumpchainpointer)->chain)
		{
			clump = *clumpchainpointer;
			if (!clump)
			{
				clump = Clump_NewClump();
				if (!clump)
					return NULL;
			}
			if (clump->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel1))
				Sys_Error("Clump_AllocBlock: trashed sentinel1\n");
			if (clump->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel2))
				Sys_Error("Clump_AllocBlock: trashed sentinel2\n");
			startbit = 0;
			endbit = startbit + needbits;
			array = clump->bits;
			// do as fast a search as possible, even if it means crude alignment
			if (needbits >= 32)
			{
				// large allocations are aligned to large boundaries
				// furthermore, they are allocated downward from the top...
				endindex = MEMBITINTS;
				startindex = endindex - needints;
				index = endindex;
				while (--index >= startindex)
				{
					if (array[index])
					{
						endindex = index;
						startindex = endindex - needints;
						if (startindex < 0)
							goto nofreeblock;
					}
				}
				startbit = startindex*32;
				goto foundblock;
			}
			else
			{
				// search for a multi-bit gap in a single int
				// (not dealing with the cases that cross two ints)
				mask = (1<<needbits)-1;
				endbit = 32-needbits;
				bit = endbit;
				for (index = 0;index < MEMBITINTS;index++)
				{
					value = array[index];
					if (value != 0xFFFFFFFFu)
					{
						// there may be room in this one...
						for (bit = 0;bit < endbit;bit++)
						{
							if (!(value & (mask<<bit)))
							{
								startbit = index*32+bit;
								goto foundblock;
							}
						}
					}
				}
				goto nofreeblock;
			}
foundblock:
			endbit = startbit + needbits;
			// mark this range as used
			// TODO: optimize
			for (bit = startbit;bit < endbit;bit++)
				if (clump->bits[bit>>5] & (1<<(bit & 31)))
					Sys_Error("Clump_AllocBlock: internal error (%i needbits)\n", needbits);
			for (bit = startbit;bit < endbit;bit++)
				clump->bits[bit>>5] |= (1<<(bit & 31));
			clump->blocksinuse += needbits;
			base = clump->block + startbit * MEMUNIT;
			if (developer_memorydebug.integer)
				memset(base, 0xBF, needbits * MEMUNIT);
			return base;
nofreeblock:
			;
		}
		// never reached
		return NULL;
	}
	// too big, allocate it directly
#endif
#if MEMCLUMPING == 2
	return NULL;
#else
	base = (unsigned char *)attempt_malloc(size);
	if (base && developer_memorydebug.integer)
		memset(base, 0xAF, size);
	return base;
#endif
}
static void Clump_FreeBlock(void *base, size_t size)
{
#if MEMCLUMPING
	unsigned int needbits;
	unsigned int startbit;
	unsigned int endbit;
	unsigned int bit;
	memclump_t **clumpchainpointer;
	memclump_t *clump;
	unsigned char *start = (unsigned char *)base;
	for (clumpchainpointer = &clumpchain;(clump = *clumpchainpointer);clumpchainpointer = &(*clumpchainpointer)->chain)
	{
		if (start >= clump->block && start < clump->block + MEMCLUMPSIZE)
		{
			if (clump->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel1))
				Sys_Error("Clump_FreeBlock: trashed sentinel1\n");
			if (clump->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel2))
				Sys_Error("Clump_FreeBlock: trashed sentinel2\n");
			if (start + size > clump->block + MEMCLUMPSIZE)
				Sys_Error("Clump_FreeBlock: block overrun\n");
			// the block belongs to this clump, clear the range
			needbits = (size + MEMUNIT - 1) / MEMUNIT;
			startbit = (start - clump->block) / MEMUNIT;
			endbit = startbit + needbits;
			// first verify all bits are set, otherwise this may be misaligned or a double free
			for (bit = startbit;bit < endbit;bit++)
				if ((clump->bits[bit>>5] & (1<<(bit & 31))) == 0)
					Sys_Error("Clump_FreeBlock: double free\n");
			for (bit = startbit;bit < endbit;bit++)
				clump->bits[bit>>5] &= ~(1<<(bit & 31));
			clump->blocksinuse -= needbits;
			memset(base, 0xFF, needbits * MEMUNIT);
			// if all has been freed, free the clump itself
			if (clump->blocksinuse == 0)
			{
				*clumpchainpointer = clump->chain;
				if (developer_memorydebug.integer)
					memset(clump, 0xFF, sizeof(*clump));
#if MEMCLUMPING != 2
				free(clump);
#endif
			}
			return;
		}
	}
	// does not belong to any known chunk...  assume it was a direct allocation
#endif
#if MEMCLUMPING != 2
	memset(base, 0xFF, size);
	free(base);
#endif
}

void *_Mem_Alloc(mempool_t *pool, void *olddata, size_t size, size_t alignment, const char *filename, int fileline)
{
	unsigned int sentinel1;
	unsigned int sentinel2;
	size_t realsize;
	size_t sharedsize;
	size_t remainsize;
	memheader_t *mem;
	memheader_t *oldmem;
	unsigned char *base;

	if (size <= 0)
	{
		if (olddata)
			_Mem_Free(olddata, filename, fileline);
		return NULL;
	}
	if (pool == NULL)
	{
		if(olddata)
			pool = ((memheader_t *)((unsigned char *) olddata - sizeof(memheader_t)))->pool;
		else
			Sys_Error("Mem_Alloc: pool == NULL (alloc at %s:%i)", filename, fileline);
	}
	if (mem_mutex)
		Thread_LockMutex(mem_mutex);
	if (developer_memory.integer || size >= developer_memoryreportlargerthanmb.value * 1048576)
		Con_DPrintf("Mem_Alloc: pool %s, file %s:%i, size %f bytes (%f MB)\n", pool->name, filename, fileline, (double)size, (double)size / 1048576.0f);
	//if (developer.integer > 0 && developer_memorydebug.integer)
	//	_Mem_CheckSentinelsGlobal(filename, fileline);
	pool->totalsize += size;
	realsize = alignment + sizeof(memheader_t) + size + sizeof(sentinel2);
	pool->realsize += realsize;
	base = (unsigned char *)Clump_AllocBlock(realsize);
	if (base == NULL)
	{
		Mem_PrintList(0);
		Mem_PrintStats();
		Mem_PrintList(1<<30);
		Mem_PrintStats();
		Sys_Error("Mem_Alloc: out of memory (alloc of size %f (%.3fMB) at %s:%i)", (double)realsize, (double)realsize / (1 << 20), filename, fileline);
	}
	// calculate address that aligns the end of the memheader_t to the specified alignment
	mem = (memheader_t*)((((size_t)base + sizeof(memheader_t) + (alignment-1)) & ~(alignment-1)) - sizeof(memheader_t));
	mem->baseaddress = (void*)base;
	mem->filename = filename;
	mem->fileline = fileline;
	mem->size = size;
	mem->pool = pool;

	// calculate sentinels (detects buffer overruns, in a way that is hard to exploit)
	sentinel1 = MEMHEADER_SENTINEL_FOR_ADDRESS(&mem->sentinel);
	sentinel2 = MEMHEADER_SENTINEL_FOR_ADDRESS((unsigned char *) mem + sizeof(memheader_t) + mem->size);
	mem->sentinel = sentinel1;
	memcpy((unsigned char *) mem + sizeof(memheader_t) + mem->size, &sentinel2, sizeof(sentinel2));

	// append to head of list
	mem->next = pool->chain;
	mem->prev = NULL;
	pool->chain = mem;
	if (mem->next)
		mem->next->prev = mem;

	if (mem_mutex)
		Thread_UnlockMutex(mem_mutex);

	// copy the shared portion in the case of a realloc, then memset the rest
	sharedsize = 0;
	remainsize = size;
	if (olddata)
	{
		oldmem = (memheader_t*)olddata - 1;
		sharedsize = min(oldmem->size, size);
		memcpy((void *)((unsigned char *) mem + sizeof(memheader_t)), olddata, sharedsize);
		remainsize -= sharedsize;
		_Mem_Free(olddata, filename, fileline);
	}
	memset((void *)((unsigned char *) mem + sizeof(memheader_t) + sharedsize), 0, remainsize);
	return (void *)((unsigned char *) mem + sizeof(memheader_t));
}

// only used by _Mem_Free and _Mem_FreePool
static void _Mem_FreeBlock(memheader_t *mem, const char *filename, int fileline)
{
	mempool_t *pool;
	size_t size;
	size_t realsize;
	unsigned int sentinel1;
	unsigned int sentinel2;

	// check sentinels (detects buffer overruns, in a way that is hard to exploit)
	sentinel1 = MEMHEADER_SENTINEL_FOR_ADDRESS(&mem->sentinel);
	sentinel2 = MEMHEADER_SENTINEL_FOR_ADDRESS((unsigned char *) mem + sizeof(memheader_t) + mem->size);
	if (mem->sentinel != sentinel1)
		Sys_Error("Mem_Free: trashed head sentinel (alloc at %s:%i, free at %s:%i)", mem->filename, mem->fileline, filename, fileline);
	if (memcmp((unsigned char *) mem + sizeof(memheader_t) + mem->size, &sentinel2, sizeof(sentinel2)))
		Sys_Error("Mem_Free: trashed tail sentinel (alloc at %s:%i, free at %s:%i)", mem->filename, mem->fileline, filename, fileline);

	pool = mem->pool;
	if (developer_memory.integer)
		Con_DPrintf("Mem_Free: pool %s, alloc %s:%i, free %s:%i, size %i bytes\n", pool->name, mem->filename, mem->fileline, filename, fileline, (int)(mem->size));
	// unlink memheader from doubly linked list
	if ((mem->prev ? mem->prev->next != mem : pool->chain != mem) || (mem->next && mem->next->prev != mem))
		Sys_Error("Mem_Free: not allocated or double freed (free at %s:%i)", filename, fileline);
	if (mem_mutex)
		Thread_LockMutex(mem_mutex);
	if (mem->prev)
		mem->prev->next = mem->next;
	else
		pool->chain = mem->next;
	if (mem->next)
		mem->next->prev = mem->prev;
	// memheader has been unlinked, do the actual free now
	size = mem->size;
	realsize = sizeof(memheader_t) + size + sizeof(sentinel2);
	pool->totalsize -= size;
	pool->realsize -= realsize;
	Clump_FreeBlock(mem->baseaddress, realsize);
	if (mem_mutex)
		Thread_UnlockMutex(mem_mutex);
}

void _Mem_Free(void *data, const char *filename, int fileline)
{
	if (data == NULL)
	{
		Con_DPrintf("Mem_Free: data == NULL (called at %s:%i)\n", filename, fileline);
		return;
	}

	if (developer_memorydebug.integer)
	{
		//_Mem_CheckSentinelsGlobal(filename, fileline);
		if (!Mem_IsAllocated(NULL, data))
			Sys_Error("Mem_Free: data is not allocated (called at %s:%i)", filename, fileline);
	}

	_Mem_FreeBlock((memheader_t *)((unsigned char *) data - sizeof(memheader_t)), filename, fileline);
}

mempool_t *_Mem_AllocPool(const char *name, int flags, mempool_t *parent, const char *filename, int fileline)
{
	mempool_t *pool;
	if (developer_memorydebug.integer)
		_Mem_CheckSentinelsGlobal(filename, fileline);
	pool = (mempool_t *)Clump_AllocBlock(sizeof(mempool_t));
	if (pool == NULL)
	{
		Mem_PrintList(0);
		Mem_PrintStats();
		Mem_PrintList(1<<30);
		Mem_PrintStats();
		Sys_Error("Mem_AllocPool: out of memory (allocpool at %s:%i)", filename, fileline);
	}
	memset(pool, 0, sizeof(mempool_t));
	pool->sentinel1 = MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel1);
	pool->sentinel2 = MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel2);
	pool->filename = filename;
	pool->fileline = fileline;
	pool->flags = flags;
	pool->chain = NULL;
	pool->totalsize = 0;
	pool->realsize = sizeof(mempool_t);
	strlcpy (pool->name, name, sizeof (pool->name));
	pool->parent = parent;
	pool->next = poolchain;
	poolchain = pool;
	return pool;
}

void _Mem_FreePool(mempool_t **poolpointer, const char *filename, int fileline)
{
	mempool_t *pool = *poolpointer;
	mempool_t **chainaddress, *iter, *temp;

	if (developer_memorydebug.integer)
		_Mem_CheckSentinelsGlobal(filename, fileline);
	if (pool)
	{
		// unlink pool from chain
		for (chainaddress = &poolchain;*chainaddress && *chainaddress != pool;chainaddress = &((*chainaddress)->next));
		if (*chainaddress != pool)
			Sys_Error("Mem_FreePool: pool already free (freepool at %s:%i)", filename, fileline);
		if (pool->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel1))
			Sys_Error("Mem_FreePool: trashed pool sentinel 1 (allocpool at %s:%i, freepool at %s:%i)", pool->filename, pool->fileline, filename, fileline);
		if (pool->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel2))
			Sys_Error("Mem_FreePool: trashed pool sentinel 2 (allocpool at %s:%i, freepool at %s:%i)", pool->filename, pool->fileline, filename, fileline);
		*chainaddress = pool->next;

		// free memory owned by the pool
		while (pool->chain)
			_Mem_FreeBlock(pool->chain, filename, fileline);

		// free child pools, too
		for(iter = poolchain; iter; iter = temp) {
			temp = iter->next;
			if(iter->parent == pool)
				_Mem_FreePool(&temp, filename, fileline);
		}

		// free the pool itself
		Clump_FreeBlock(pool, sizeof(*pool));

		*poolpointer = NULL;
	}
}

void _Mem_EmptyPool(mempool_t *pool, const char *filename, int fileline)
{
	mempool_t *chainaddress;

	if (developer_memorydebug.integer)
	{
		//_Mem_CheckSentinelsGlobal(filename, fileline);
		// check if this pool is in the poolchain
		for (chainaddress = poolchain;chainaddress;chainaddress = chainaddress->next)
			if (chainaddress == pool)
				break;
		if (!chainaddress)
			Sys_Error("Mem_EmptyPool: pool is already free (emptypool at %s:%i)", filename, fileline);
	}
	if (pool == NULL)
		Sys_Error("Mem_EmptyPool: pool == NULL (emptypool at %s:%i)", filename, fileline);
	if (pool->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel1))
		Sys_Error("Mem_EmptyPool: trashed pool sentinel 1 (allocpool at %s:%i, emptypool at %s:%i)", pool->filename, pool->fileline, filename, fileline);
	if (pool->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel2))
		Sys_Error("Mem_EmptyPool: trashed pool sentinel 2 (allocpool at %s:%i, emptypool at %s:%i)", pool->filename, pool->fileline, filename, fileline);

	// free memory owned by the pool
	while (pool->chain)
		_Mem_FreeBlock(pool->chain, filename, fileline);

	// empty child pools, too
	for(chainaddress = poolchain; chainaddress; chainaddress = chainaddress->next)
		if(chainaddress->parent == pool)
			_Mem_EmptyPool(chainaddress, filename, fileline);

}

void _Mem_CheckSentinels(void *data, const char *filename, int fileline)
{
	memheader_t *mem;
	unsigned int sentinel1;
	unsigned int sentinel2;

	if (data == NULL)
		Sys_Error("Mem_CheckSentinels: data == NULL (sentinel check at %s:%i)", filename, fileline);

	mem = (memheader_t *)((unsigned char *) data - sizeof(memheader_t));
	sentinel1 = MEMHEADER_SENTINEL_FOR_ADDRESS(&mem->sentinel);
	sentinel2 = MEMHEADER_SENTINEL_FOR_ADDRESS((unsigned char *) mem + sizeof(memheader_t) + mem->size);
	if (mem->sentinel != sentinel1)
		Sys_Error("Mem_Free: trashed head sentinel (alloc at %s:%i, sentinel check at %s:%i)", mem->filename, mem->fileline, filename, fileline);
	if (memcmp((unsigned char *) mem + sizeof(memheader_t) + mem->size, &sentinel2, sizeof(sentinel2)))
		Sys_Error("Mem_Free: trashed tail sentinel (alloc at %s:%i, sentinel check at %s:%i)", mem->filename, mem->fileline, filename, fileline);
}

#if MEMCLUMPING
static void _Mem_CheckClumpSentinels(memclump_t *clump, const char *filename, int fileline)
{
	// this isn't really very useful
	if (clump->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel1))
		Sys_Error("Mem_CheckClumpSentinels: trashed sentinel 1 (sentinel check at %s:%i)", filename, fileline);
	if (clump->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&clump->sentinel2))
		Sys_Error("Mem_CheckClumpSentinels: trashed sentinel 2 (sentinel check at %s:%i)", filename, fileline);
}
#endif

void _Mem_CheckSentinelsGlobal(const char *filename, int fileline)
{
	memheader_t *mem;
#if MEMCLUMPING
	memclump_t *clump;
#endif
	mempool_t *pool;
	for (pool = poolchain;pool;pool = pool->next)
	{
		if (pool->sentinel1 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel1))
			Sys_Error("Mem_CheckSentinelsGlobal: trashed pool sentinel 1 (allocpool at %s:%i, sentinel check at %s:%i)", pool->filename, pool->fileline, filename, fileline);
		if (pool->sentinel2 != MEMHEADER_SENTINEL_FOR_ADDRESS(&pool->sentinel2))
			Sys_Error("Mem_CheckSentinelsGlobal: trashed pool sentinel 2 (allocpool at %s:%i, sentinel check at %s:%i)", pool->filename, pool->fileline, filename, fileline);
	}
	for (pool = poolchain;pool;pool = pool->next)
		for (mem = pool->chain;mem;mem = mem->next)
			_Mem_CheckSentinels((void *)((unsigned char *) mem + sizeof(memheader_t)), filename, fileline);
#if MEMCLUMPING
	for (pool = poolchain;pool;pool = pool->next)
		for (clump = clumpchain;clump;clump = clump->chain)
			_Mem_CheckClumpSentinels(clump, filename, fileline);
#endif
}

qboolean Mem_IsAllocated(mempool_t *pool, void *data)
{
	memheader_t *header;
	memheader_t *target;

	if (pool)
	{
		// search only one pool
		target = (memheader_t *)((unsigned char *) data - sizeof(memheader_t));
		for( header = pool->chain ; header ; header = header->next )
			if( header == target )
				return true;
	}
	else
	{
		// search all pools
		for (pool = poolchain;pool;pool = pool->next)
			if (Mem_IsAllocated(pool, data))
				return true;
	}
	return false;
}

void Mem_ExpandableArray_NewArray(memexpandablearray_t *l, mempool_t *mempool, size_t recordsize, int numrecordsperarray)
{
	memset(l, 0, sizeof(*l));
	l->mempool = mempool;
	l->recordsize = recordsize;
	l->numrecordsperarray = numrecordsperarray;
}

void Mem_ExpandableArray_FreeArray(memexpandablearray_t *l)
{
	size_t i;
	if (l->maxarrays)
	{
		for (i = 0;i != l->numarrays;i++)
			Mem_Free(l->arrays[i].data);
		Mem_Free(l->arrays);
	}
	memset(l, 0, sizeof(*l));
}

void *Mem_ExpandableArray_AllocRecord(memexpandablearray_t *l)
{
	size_t i, j;
	for (i = 0;;i++)
	{
		if (i == l->numarrays)
		{
			if (l->numarrays == l->maxarrays)
			{
				memexpandablearray_array_t *oldarrays = l->arrays;
				l->maxarrays = max(l->maxarrays * 2, 128);
				l->arrays = (memexpandablearray_array_t*) Mem_Alloc(l->mempool, l->maxarrays * sizeof(*l->arrays));
				if (oldarrays)
				{
					memcpy(l->arrays, oldarrays, l->numarrays * sizeof(*l->arrays));
					Mem_Free(oldarrays);
				}
			}
			l->arrays[i].numflaggedrecords = 0;
			l->arrays[i].data = (unsigned char *) Mem_Alloc(l->mempool, (l->recordsize + 1) * l->numrecordsperarray);
			l->arrays[i].allocflags = l->arrays[i].data + l->recordsize * l->numrecordsperarray;
			l->numarrays++;
		}
		if (l->arrays[i].numflaggedrecords < l->numrecordsperarray)
		{
			for (j = 0;j < l->numrecordsperarray;j++)
			{
				if (!l->arrays[i].allocflags[j])
				{
					l->arrays[i].allocflags[j] = true;
					l->arrays[i].numflaggedrecords++;
					memset(l->arrays[i].data + l->recordsize * j, 0, l->recordsize);
					return (void *)(l->arrays[i].data + l->recordsize * j);
				}
			}
		}
	}
}

/*****************************************************************************
 * IF YOU EDIT THIS:
 * If this function was to change the size of the "expandable" array, you have
 * to update r_shadow.c
 * Just do a search for "range =", R_ShadowClearWorldLights would be the first
 * function to look at. (And also seems like the only one?) You  might have to
 * move the  call to Mem_ExpandableArray_IndexRange  back into for(...) loop's
 * condition
 */
void Mem_ExpandableArray_FreeRecord(memexpandablearray_t *l, void *record) // const!
{
	size_t i, j;
	unsigned char *p = (unsigned char *)record;
	for (i = 0;i != l->numarrays;i++)
	{
		if (p >= l->arrays[i].data && p < (l->arrays[i].data + l->recordsize * l->numrecordsperarray))
		{
			j = (p - l->arrays[i].data) / l->recordsize;
			if (p != l->arrays[i].data + j * l->recordsize)
				Sys_Error("Mem_ExpandableArray_FreeRecord: no such record %p\n", p);
			if (!l->arrays[i].allocflags[j])
				Sys_Error("Mem_ExpandableArray_FreeRecord: record %p is already free!\n", p);
			l->arrays[i].allocflags[j] = false;
			l->arrays[i].numflaggedrecords--;
			return;
		}
	}
}

size_t Mem_ExpandableArray_IndexRange(const memexpandablearray_t *l)
{
	size_t i, j, k, end = 0;
	for (i = 0;i < l->numarrays;i++)
	{
		for (j = 0, k = 0;k < l->arrays[i].numflaggedrecords;j++)
		{
			if (l->arrays[i].allocflags[j])
			{
				end = l->numrecordsperarray * i + j + 1;
				k++;
			}
		}
	}
	return end;
}

void *Mem_ExpandableArray_RecordAtIndex(const memexpandablearray_t *l, size_t index)
{
	size_t i, j;
	i = index / l->numrecordsperarray;
	j = index % l->numrecordsperarray;
	if (i >= l->numarrays || !l->arrays[i].allocflags[j])
		return NULL;
	return (void *)(l->arrays[i].data + j * l->recordsize);
}


// used for temporary memory allocations around the engine, not for longterm
// storage, if anything in this pool stays allocated during gameplay, it is
// considered a leak
mempool_t *tempmempool;
// only for zone
mempool_t *zonemempool;

void Mem_PrintStats(void)
{
	size_t count = 0, size = 0, realsize = 0;
	mempool_t *pool;
	memheader_t *mem;
	Mem_CheckSentinelsGlobal();
	for (pool = poolchain;pool;pool = pool->next)
	{
		count++;
		size += pool->totalsize;
		realsize += pool->realsize;
	}
	Con_Printf("%lu memory pools, totalling %lu bytes (%.3fMB)\n", (unsigned long)count, (unsigned long)size, size / 1048576.0);
	Con_Printf("total allocated size: %lu bytes (%.3fMB)\n", (unsigned long)realsize, realsize / 1048576.0);
	for (pool = poolchain;pool;pool = pool->next)
	{
		if ((pool->flags & POOLFLAG_TEMP) && pool->chain)
		{
			Con_Printf("Memory pool %p has sprung a leak totalling %lu bytes (%.3fMB)!  Listing contents...\n", (void *)pool, (unsigned long)pool->totalsize, pool->totalsize / 1048576.0);
			for (mem = pool->chain;mem;mem = mem->next)
				Con_Printf("%10lu bytes allocated at %s:%i\n", (unsigned long)mem->size, mem->filename, mem->fileline);
		}
	}
}

void Mem_PrintList(size_t minallocationsize)
{
	mempool_t *pool;
	memheader_t *mem;
	Mem_CheckSentinelsGlobal();
	Con_Print("memory pool list:\n"
	           "size    name\n");
	for (pool = poolchain;pool;pool = pool->next)
	{
		Con_Printf("%10luk (%10luk actual) %s (%+li byte change) %s\n", (unsigned long) ((pool->totalsize + 1023) / 1024), (unsigned long)((pool->realsize + 1023) / 1024), pool->name, (long)(pool->totalsize - pool->lastchecksize), (pool->flags & POOLFLAG_TEMP) ? "TEMP" : "");
		pool->lastchecksize = pool->totalsize;
		for (mem = pool->chain;mem;mem = mem->next)
			if (mem->size >= minallocationsize)
				Con_Printf("%10lu bytes allocated at %s:%i\n", (unsigned long)mem->size, mem->filename, mem->fileline);
	}
}

static void MemList_f(void)
{
	switch(Cmd_Argc())
	{
	case 1:
		Mem_PrintList(1<<30);
		Mem_PrintStats();
		break;
	case 2:
		Mem_PrintList(atoi(Cmd_Argv(1)) * 1024);
		Mem_PrintStats();
		break;
	default:
		Con_Print("MemList_f: unrecognized options\nusage: memlist [all]\n");
		break;
	}
}

static void MemStats_f(void)
{
	Mem_CheckSentinelsGlobal();
	R_TextureStats_Print(false, false, true);
	GL_Mesh_ListVBOs(false);
	Mem_PrintStats();
}


char* Mem_strdup (mempool_t *pool, const char* s)
{
	char* p;
	size_t sz;
	if (s == NULL)
		return NULL;
	sz = strlen (s) + 1;
	p = (char*)Mem_Alloc (pool, sz);
	strlcpy (p, s, sz);
	return p;
}

/*
========================
Memory_Init
========================
*/
void Memory_Init (void)
{
	static union {unsigned short s;unsigned char b[2];} u;
	u.s = 0x100;
	mem_bigendian = u.b[0] != 0;

	sentinel_seed = rand();
	poolchain = NULL;
	tempmempool = Mem_AllocPool("Temporary Memory", POOLFLAG_TEMP, NULL);
	zonemempool = Mem_AllocPool("Zone", 0, NULL);

	if (Thread_HasThreads())
		mem_mutex = Thread_CreateMutex();
}

void Memory_Shutdown (void)
{
//	Mem_FreePool (&zonemempool);
//	Mem_FreePool (&tempmempool);

	if (mem_mutex)
		Thread_DestroyMutex(mem_mutex);
	mem_mutex = NULL;
}

void Memory_Init_Commands (void)
{
	Cmd_AddCommand ("memstats", MemStats_f, "prints memory system statistics");
	Cmd_AddCommand ("memlist", MemList_f, "prints memory pool information (or if used as memlist 5 lists individual allocations of 5K or larger, 0 lists all allocations)");
	Cvar_RegisterVariable (&developer_memory);
	Cvar_RegisterVariable (&developer_memorydebug);
	Cvar_RegisterVariable (&developer_memoryreportlargerthanmb);
	Cvar_RegisterVariable (&sys_memsize_physical);
	Cvar_RegisterVariable (&sys_memsize_virtual);

#if defined(WIN32)
#ifdef _WIN64
	{
		MEMORYSTATUSEX status;
		// first guess
		Cvar_SetValueQuick(&sys_memsize_virtual, 8388608);
		// then improve
		status.dwLength = sizeof(status);
		if(GlobalMemoryStatusEx(&status))
		{
			Cvar_SetValueQuick(&sys_memsize_physical, status.ullTotalPhys / 1048576.0);
			Cvar_SetValueQuick(&sys_memsize_virtual, min(sys_memsize_virtual.value, status.ullTotalVirtual / 1048576.0));
		}
	}
#else
	{
		MEMORYSTATUS status;
		// first guess
		Cvar_SetValueQuick(&sys_memsize_virtual, 2048);
		// then improve
		status.dwLength = sizeof(status);
		GlobalMemoryStatus(&status);
		Cvar_SetValueQuick(&sys_memsize_physical, status.dwTotalPhys / 1048576.0);
		Cvar_SetValueQuick(&sys_memsize_virtual, min(sys_memsize_virtual.value, status.dwTotalVirtual / 1048576.0));
	}
#endif
#else
	{
		// first guess
		Cvar_SetValueQuick(&sys_memsize_virtual, (sizeof(void*) == 4) ? 2048 : 268435456);
		// then improve
		{
			// Linux, and BSD with linprocfs mounted
			FILE *f = fopen("/proc/meminfo", "r");
			if(f)
			{
				static char buf[1024];
				while(fgets(buf, sizeof(buf), f))
				{
					const char *p = buf;
					if(!COM_ParseToken_Console(&p))
						continue;
					if(!strcmp(com_token, "MemTotal:"))
					{
						if(!COM_ParseToken_Console(&p))
							continue;
						Cvar_SetValueQuick(&sys_memsize_physical, atof(com_token) / 1024.0);
					}
					if(!strcmp(com_token, "SwapTotal:"))
					{
						if(!COM_ParseToken_Console(&p))
							continue;
						Cvar_SetValueQuick(&sys_memsize_virtual, min(sys_memsize_virtual.value , atof(com_token) / 1024.0 + sys_memsize_physical.value));
					}
				}
				fclose(f);
			}
		}
	}
#endif
}