summaryrefslogtreecommitdiff
path: root/source/fitz/memento.c
blob: a8708c33474681adf5fa04e8716b4e555a148fb0 (plain)
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
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
/* Copyright (C) 2001-2013 Artifex Software, Inc.
   All Rights Reserved.

   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied, modified
   or distributed except as expressly authorized under the terms of that
   license. Refer to licensing information at http://www.artifex.com
   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
*/

/* Inspired by Fortify by Simon P Bullen. */

/* Set the following if you're only looking for leaks, not memory overwrites
 * to speed the operation */
/* #define MEMENTO_LEAKONLY */

/* Don't keep blocks around if they'd mean losing more than a quarter of
 * the freelist. */
#define MEMENTO_FREELIST_MAX_SINGLE_BLOCK (MEMENTO_FREELIST_MAX/4)

#define COMPILING_MEMENTO_C

/* We have some GS specific tweaks; more for the GS build environment than
 * anything else. */
#undef MEMENTO_GS_HACKS

#ifdef MEMENTO_GS_HACKS
/* For GS we include malloc_.h. Anyone else would just include memento.h */
#include "malloc_.h"
#ifdef __MACH__
#include <string.h>
#else
#ifndef memset
void *memset(void *,int,size_t);
#endif
#endif
int atexit(void (*)(void));
#else
#include "mupdf/memento.h"
#include <stdio.h>
#include <stdlib.h>
#endif

#ifdef MEMENTO_ANDROID
#include <android/log.h>

static int
android_fprintf(FILE *file, const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	__android_log_vprint(ANDROID_LOG_ERROR,"memento", fmt, args);
	va_end(args);
}

#define fprintf android_fprintf
#define MEMENTO_STACKTRACE_METHOD 0
#endif

#if defined(_WIN32) || defined(_WIN64)
#include <windows.h>

static int
windows_fprintf(FILE *file, const char *fmt, ...)
{
	va_list args;
	char text[4096];
	int ret;

	va_start(args, fmt);
	ret = vfprintf(file, fmt, args);
	va_end(args);

	va_start(args, fmt);
	vsnprintf(text, 4096, fmt, args);
	OutputDebugStringA(text);
	va_end(args);

	return ret;
}

#define fprintf windows_fprintf
#endif

#ifndef MEMENTO_STACKTRACE_METHOD
#ifdef __GNUC__
#define MEMENTO_STACKTRACE_METHOD 1
#endif
#endif

#if defined(__linux__)
#define MEMENTO_HAS_FORK
#elif defined(__APPLE__) && defined(__MACH__)
#define MEMENTO_HAS_FORK
#endif

/* Define the underlying allocators, just in case */
void *MEMENTO_UNDERLYING_MALLOC(size_t);
void MEMENTO_UNDERLYING_FREE(void *);
void *MEMENTO_UNDERLYING_REALLOC(void *,size_t);
void *MEMENTO_UNDERLYING_CALLOC(size_t,size_t);

/* And some other standard functions we use. We don't include the header
 * files, just in case they pull in unexpected others. */
int atoi(const char *);
char *getenv(const char *);

/* How far to search for pointers in each block when calculating nestings */
/* mupdf needs at least 34000ish (sizeof(fz_shade))/ */
#define MEMENTO_PTRSEARCH 65536

#ifndef MEMENTO_MAXPATTERN
#define MEMENTO_MAXPATTERN 0
#endif

#ifdef MEMENTO

#ifdef MEMENTO_GS_HACKS
#include "valgrind.h"
#else
#ifdef HAVE_VALGRIND
#include "valgrind/memcheck.h"
#else
#define VALGRIND_MAKE_MEM_NOACCESS(p,s)  do { } while (0==1)
#define VALGRIND_MAKE_MEM_UNDEFINED(p,s)  do { } while (0==1)
#define VALGRIND_MAKE_MEM_DEFINED(p,s)  do { } while (0==1)
#endif
#endif

enum {
    Memento_PreSize  = 16,
    Memento_PostSize = 16
};

enum {
    Memento_Flag_OldBlock = 1,
    Memento_Flag_HasParent = 2,
    Memento_Flag_BreakOnFree = 4,
    Memento_Flag_BreakOnRealloc = 8
};

/* When we list leaked blocks at the end of execution, we search for pointers
 * between blocks in order to be able to give a nice nested view.
 * Unfortunately, if you have are running your own allocator (such as
 * ghostscripts chunk allocator) you can often find that the header of the
 * block always contains pointers to next or previous blocks. This tends to
 * mean the nesting displayed is "uninteresting" at best :)
 *
 * As a hack to get around this, we have a define MEMENTO_SKIP_SEARCH that
 * indicates how many bytes to skip over at the start of the chunk.
 * This may cause us to miss true nestings, but such is life...
 */
#ifndef MEMENTO_SEARCH_SKIP
#ifdef MEMENTO_GS_HACKS
#define MEMENTO_SEARCH_SKIP (2*sizeof(void *))
#else
#define MEMENTO_SEARCH_SKIP 0
#endif
#endif

typedef struct Memento_BlkHeader Memento_BlkHeader;

struct Memento_BlkHeader
{
    size_t             rawsize;
    int                sequence;
    int                lastCheckedOK;
    int                flags;
    Memento_BlkHeader *next;
    Memento_BlkHeader *parent; /* Only used while printing out nested list */

    const char        *label;

    /* Entries for nesting display calculations */
    Memento_BlkHeader *child;
    Memento_BlkHeader *sibling;

    char               preblk[Memento_PreSize];
};

/* In future this could (should) be a smarter data structure, like, say,
 * splay trees. For now, we use a list.
 */
typedef struct Memento_Blocks
{
    Memento_BlkHeader  *head;
    Memento_BlkHeader **tail;
} Memento_Blocks;

/* And our global structure */
static struct {
    int            inited;
    Memento_Blocks used;
    Memento_Blocks free;
    size_t         freeListSize;
    int            sequence;
    int            paranoia;
    int            paranoidAt;
    int            countdown;
    int            lastChecked;
    int            breakAt;
    int            failAt;
    int            failing;
    int            nextFailAt;
    int            squeezeAt;
    int            squeezing;
    int            segv;
    int            pattern;
    int            nextPattern;
    int            patternBit;
    size_t         maxMemory;
    size_t         alloc;
    size_t         peakAlloc;
    size_t         totalAlloc;
    size_t         numMallocs;
    size_t         numFrees;
    size_t         numReallocs;
} globals;

#define MEMENTO_EXTRASIZE (sizeof(Memento_BlkHeader) + Memento_PostSize)

/* Round up size S to the next multiple of N (where N is a power of 2) */
#define MEMENTO_ROUNDUP(S,N) ((S + N-1)&~(N-1))

#define MEMBLK_SIZE(s) MEMENTO_ROUNDUP(s + MEMENTO_EXTRASIZE, MEMENTO_MAXALIGN)

#define MEMBLK_FROMBLK(B)   (&((Memento_BlkHeader*)(void *)(B))[-1])
#define MEMBLK_TOBLK(B)     ((void*)(&((Memento_BlkHeader*)(void*)(B))[1]))
#define MEMBLK_POSTPTR(B) \
          (&((char *)(void *)(B))[(B)->rawsize + sizeof(Memento_BlkHeader)])

void Memento_breakpoint(void)
{
    /* A handy externally visible function for breakpointing */
#if 0 /* Enable this to force automatic breakpointing */
#ifdef DEBUG
#ifdef _MSC_VER
    __asm int 3;
#endif
#endif
#endif
}

static void Memento_addBlockHead(Memento_Blocks    *blks,
                                 Memento_BlkHeader *b,
                                 int                type)
{
    if (blks->tail == &blks->head) {
        /* Adding into an empty list, means the tail changes too */
        blks->tail = &b->next;
    }
    b->next    = blks->head;
    blks->head = b;
#ifndef MEMENTO_LEAKONLY
    memset(b->preblk, MEMENTO_PREFILL, Memento_PreSize);
    memset(MEMBLK_POSTPTR(b), MEMENTO_POSTFILL, Memento_PostSize);
#endif
    VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_POSTPTR(b), Memento_PostSize);
    if (type == 0) { /* malloc */
        VALGRIND_MAKE_MEM_UNDEFINED(MEMBLK_TOBLK(b), b->rawsize);
    } else if (type == 1) { /* free */
        VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_TOBLK(b), b->rawsize);
    }
    VALGRIND_MAKE_MEM_NOACCESS(b, sizeof(Memento_BlkHeader));
}

static void Memento_addBlockTail(Memento_Blocks    *blks,
                                 Memento_BlkHeader *b,
                                 int                type)
{
    VALGRIND_MAKE_MEM_DEFINED(blks->tail, sizeof(Memento_BlkHeader *));
    *blks->tail = b;
    blks->tail  = &b->next;
    b->next = NULL;
    VALGRIND_MAKE_MEM_NOACCESS(blks->tail, sizeof(Memento_BlkHeader *));
#ifndef MEMENTO_LEAKONLY
    memset(b->preblk, MEMENTO_PREFILL, Memento_PreSize);
    memset(MEMBLK_POSTPTR(b), MEMENTO_POSTFILL, Memento_PostSize);
#endif
    VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_POSTPTR(b), Memento_PostSize);
    if (type == 0) { /* malloc */
        VALGRIND_MAKE_MEM_UNDEFINED(MEMBLK_TOBLK(b), b->rawsize);
    } else if (type == 1) { /* free */
        VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_TOBLK(b), b->rawsize);
    }
    VALGRIND_MAKE_MEM_NOACCESS(b, sizeof(Memento_BlkHeader));
}

typedef struct BlkCheckData {
    int found;
    int preCorrupt;
    int postCorrupt;
    int freeCorrupt;
    int index;
} BlkCheckData;

static int Memento_Internal_checkAllocedBlock(Memento_BlkHeader *b, void *arg)
{
#ifndef MEMENTO_LEAKONLY
    int           i;
    char         *p;
    int           corrupt = 0;
    BlkCheckData *data = (BlkCheckData *)arg;

    p = b->preblk;
    i = Memento_PreSize;
    do {
        corrupt |= (*p++ ^ (char)MEMENTO_PREFILL);
    } while (--i);
    if (corrupt) {
        data->preCorrupt = 1;
    }
    p = MEMBLK_POSTPTR(b);
    i = Memento_PreSize;
    do {
        corrupt |= (*p++ ^ (char)MEMENTO_POSTFILL);
    } while (--i);
    if (corrupt) {
        data->postCorrupt = 1;
    }
    if ((data->freeCorrupt | data->preCorrupt | data->postCorrupt) == 0) {
        b->lastCheckedOK = globals.sequence;
    }
    data->found |= 1;
#endif
    return 0;
}

static int Memento_Internal_checkFreedBlock(Memento_BlkHeader *b, void *arg)
{
#ifndef MEMENTO_LEAKONLY
    int           i;
    char         *p;
    BlkCheckData *data = (BlkCheckData *)arg;

    p = MEMBLK_TOBLK(b);
    i = b->rawsize;
    /* Attempt to speed this up by checking an (aligned) int at a time */
    do {
        if (((size_t)p) & 1) {
            if (*p++ != (char)MEMENTO_FREEFILL)
                break;
            i--;
            if (i == 0)
                break;
        }
        if ((i >= 2) && (((size_t)p) & 2)) {
            if (*(short *)p != (short)(MEMENTO_FREEFILL | (MEMENTO_FREEFILL<<8)))
                goto mismatch;
            p += 2;
            i -= 2;
            if (i == 0)
                break;
        }
        i -= 4;
        while (i >= 0) {
            if (*(int *)p != (MEMENTO_FREEFILL |
                              (MEMENTO_FREEFILL<<8) |
                              (MEMENTO_FREEFILL<<16) |
                              (MEMENTO_FREEFILL<<24)))
                goto mismatch;
            p += 4;
            i -= 4;
        }
        i += 4;
        if ((i >= 2) && (((size_t)p) & 2)) {
            if (*(short *)p != (short)(MEMENTO_FREEFILL | (MEMENTO_FREEFILL<<8)))
                goto mismatch;
            p += 2;
            i -= 2;
        }
mismatch:
        while (i) {
            if (*p++ != (char)MEMENTO_FREEFILL)
                break;
            i--;
        }
    } while (0);
    if (i) {
        data->freeCorrupt = 1;
        data->index       = b->rawsize-i;
    }
    return Memento_Internal_checkAllocedBlock(b, arg);
#else
    return 0;
#endif
}

static void Memento_removeBlock(Memento_Blocks    *blks,
                                Memento_BlkHeader *b)
{
    Memento_BlkHeader *head = blks->head;
    Memento_BlkHeader *prev = NULL;
    while ((head) && (head != b)) {
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(*head));
        prev = head;
        head = head->next;
        VALGRIND_MAKE_MEM_NOACCESS(prev, sizeof(*prev));
    }
    if (head == NULL) {
        /* FAIL! Will have been reported to user earlier, so just exit. */
        return;
    }
    VALGRIND_MAKE_MEM_DEFINED(blks->tail, sizeof(*blks->tail));
    if (*blks->tail == head) {
        /* Removing the tail of the list */
        if (prev == NULL) {
            /* Which is also the head */
            blks->tail = &blks->head;
        } else {
            /* Which isn't the head */
            blks->tail = &prev->next;
        }
    }
    if (prev == NULL) {
        /* Removing from the head of the list */
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(*head));
        blks->head = head->next;
        VALGRIND_MAKE_MEM_NOACCESS(head, sizeof(*head));
    } else {
        /* Removing from not-the-head */
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(*head));
        VALGRIND_MAKE_MEM_DEFINED(prev, sizeof(*prev));
        prev->next = head->next;
        VALGRIND_MAKE_MEM_NOACCESS(head, sizeof(*head));
        VALGRIND_MAKE_MEM_NOACCESS(prev, sizeof(*prev));
    }
}

static int Memento_Internal_makeSpace(size_t space)
{
    /* If too big, it can never go on the freelist */
    if (space > MEMENTO_FREELIST_MAX_SINGLE_BLOCK)
        return 0;
    /* Pretend we added it on. */
    globals.freeListSize += space;
    /* Ditch blocks until it fits within our limit */
    while (globals.freeListSize > MEMENTO_FREELIST_MAX) {
        Memento_BlkHeader *head = globals.free.head;
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(*head));
        globals.free.head = head->next;
        globals.freeListSize -= MEMBLK_SIZE(head->rawsize);
        MEMENTO_UNDERLYING_FREE(head);
    }
    /* Make sure we haven't just completely emptied the free list */
    /* (This should never happen, but belt and braces... */
    if (globals.free.head == NULL)
        globals.free.tail = &globals.free.head;
    return 1;
}

static int Memento_appBlocks(Memento_Blocks *blks,
                             int             (*app)(Memento_BlkHeader *,
                                                    void *),
                             void           *arg)
{
    Memento_BlkHeader *head = blks->head;
    Memento_BlkHeader *next;
    int                result;
    while (head) {
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(Memento_BlkHeader));
        VALGRIND_MAKE_MEM_DEFINED(MEMBLK_TOBLK(head),
                                  head->rawsize + Memento_PostSize);
        result = app(head, arg);
        next = head->next;
        VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_POSTPTR(head), Memento_PostSize);
        VALGRIND_MAKE_MEM_NOACCESS(head, sizeof(Memento_BlkHeader));
        if (result)
            return result;
        head = next;
    }
    return 0;
}

static int Memento_appBlock(Memento_Blocks    *blks,
                            int                (*app)(Memento_BlkHeader *,
                                                      void *),
                            void              *arg,
                            Memento_BlkHeader *b)
{
    Memento_BlkHeader *head = blks->head;
    Memento_BlkHeader *next;
    int                result;
    while (head && head != b) {
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(Memento_BlkHeader));
        next = head->next;
        VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_POSTPTR(head), Memento_PostSize);
        head = next;
    }
    if (head == b) {
        VALGRIND_MAKE_MEM_DEFINED(head, sizeof(Memento_BlkHeader));
        VALGRIND_MAKE_MEM_DEFINED(MEMBLK_TOBLK(head),
                                  head->rawsize + Memento_PostSize);
        result = app(head, arg);
        VALGRIND_MAKE_MEM_NOACCESS(MEMBLK_POSTPTR(head), Memento_PostSize);
        VALGRIND_MAKE_MEM_NOACCESS(head, sizeof(Memento_BlkHeader));
        return result;
    }
    return 0;
}

static void showBlock(Memento_BlkHeader *b, int space)
{
    fprintf(stderr, "0x%p:(size=%d,num=%d)",
            MEMBLK_TOBLK(b), (int)b->rawsize, b->sequence);
    if (b->label)
        fprintf(stderr, "%c(%s)", space, b->label);
}

static void blockDisplay(Memento_BlkHeader *b, int n)
{
    n++;
    while (n > 40)
    {
            fprintf(stderr, "*");
            n -= 40;
    }
    while(n > 0)
    {
        int i = n;
        if (i > 32)
            i = 32;
        n -= i;
        fprintf(stderr, "%s", &"                                "[32-i]);
    }
    showBlock(b, '\t');
    fprintf(stderr, "\n");
}

static int Memento_listBlock(Memento_BlkHeader *b,
                             void              *arg)
{
    int *counts = (int *)arg;
    blockDisplay(b, 0);
    counts[0]++;
    counts[1]+= b->rawsize;
    return 0;
}

static void doNestedDisplay(Memento_BlkHeader *b,
                            int depth)
{
    /* Try and avoid recursion if we can help it */
    do {
        blockDisplay(b, depth);
        if (b->sibling) {
            if (b->child)
                doNestedDisplay(b->child, depth+1);
            b = b->sibling;
        } else {
            b = b->child;
            depth++;
        }
    } while (b);
}

static int ptrcmp(const void *a_, const void *b_)
{
    const char **a = (const char **)a_;
    const char **b = (const char **)b_;
    return (int)(*a-*b);
}

static
int Memento_listBlocksNested(void)
{
    int count, size, i;
    Memento_BlkHeader *b;
    void **blocks, *minptr, *maxptr;
    long mask;

    /* Count the blocks */
    count = 0;
    size = 0;
    for (b = globals.used.head; b; b = b->next) {
        size += b->rawsize;
        count++;
    }

    /* Make our block list */
    blocks = MEMENTO_UNDERLYING_MALLOC(sizeof(void *) * count);
    if (blocks == NULL)
        return 1;

    /* Populate our block list */
    b = globals.used.head;
    minptr = maxptr = MEMBLK_TOBLK(b);
    mask = (long)minptr;
    for (i = 0; b; b = b->next, i++) {
        void *p = MEMBLK_TOBLK(b);
        mask &= (long)p;
        if (p < minptr)
            minptr = p;
        if (p > maxptr)
            maxptr = p;
        blocks[i] = p;
        b->flags &= ~Memento_Flag_HasParent;
        b->child   = NULL;
        b->sibling = NULL;
        b->parent  = NULL;
    }
    qsort(blocks, count, sizeof(void *), ptrcmp);

    /* Now, calculate tree */
    for (b = globals.used.head; b; b = b->next) {
        char *p = MEMBLK_TOBLK(b);
        int end = (b->rawsize < MEMENTO_PTRSEARCH ? b->rawsize : MEMENTO_PTRSEARCH);
        for (i = MEMENTO_SEARCH_SKIP; i < end; i += sizeof(void *)) {
            void *q = *(void **)(&p[i]);
            void **r;

            /* Do trivial checks on pointer */
            if ((mask & (int)q) != mask || q < minptr || q > maxptr)
                continue;

            /* Search for pointer */
            r = bsearch(&q, blocks, count, sizeof(void *), ptrcmp);
            if (r) {
                /* Found child */
                Memento_BlkHeader *child = MEMBLK_FROMBLK(*r);
                Memento_BlkHeader *parent;

                /* We're assuming tree structure, not graph - ignore second
                 * and subsequent pointers. */
                if (child->parent != NULL)
                    continue;
                if (child->flags & Memento_Flag_HasParent)
                    continue;

                /* We're also assuming acyclicness here. If this is one of
                 * our parents, ignore it. */
                parent = b->parent;
                while (parent != NULL && parent != child)
                    parent = parent->parent;
                if (parent == child)
                    continue;

                child->sibling = b->child;
                b->child = child;
                child->parent = b;
                child->flags |= Memento_Flag_HasParent;
            }
        }
    }

    /* Now display with nesting */
    for (b = globals.used.head; b; b = b->next) {
        if ((b->flags & Memento_Flag_HasParent) == 0)
            doNestedDisplay(b, 0);
    }
    fprintf(stderr, " Total number of blocks = %d\n", count);
    fprintf(stderr, " Total size of blocks = %d\n", size);

    MEMENTO_UNDERLYING_FREE(blocks);
    return 0;
}

void Memento_listBlocks(void)
{
    fprintf(stderr, "Allocated blocks:\n");
    if (Memento_listBlocksNested())
    {
        int counts[2];
        counts[0] = 0;
        counts[1] = 0;
        Memento_appBlocks(&globals.used, Memento_listBlock, &counts[0]);
        fprintf(stderr, " Total number of blocks = %d\n", counts[0]);
        fprintf(stderr, " Total size of blocks = %d\n", counts[1]);
    }
}

static int Memento_listNewBlock(Memento_BlkHeader *b,
                                void              *arg)
{
    if (b->flags & Memento_Flag_OldBlock)
        return 0;
    b->flags |= Memento_Flag_OldBlock;
    return Memento_listBlock(b, arg);
}

void Memento_listNewBlocks(void) {
    int counts[2];
    counts[0] = 0;
    counts[1] = 0;
    fprintf(stderr, "Blocks allocated and still extant since last list:\n");
    Memento_appBlocks(&globals.used, Memento_listNewBlock, &counts[0]);
    fprintf(stderr, "  Total number of blocks = %d\n", counts[0]);
    fprintf(stderr, "  Total size of blocks = %d\n", counts[1]);
}

static void Memento_endStats(void)
{
    fprintf(stderr, "Total memory malloced = %u bytes\n", (unsigned int)globals.totalAlloc);
    fprintf(stderr, "Peak memory malloced = %u bytes\n", (unsigned int)globals.peakAlloc);
    fprintf(stderr, "%u mallocs, %u frees, %u reallocs\n", (unsigned int)globals.numMallocs,
            (unsigned int)globals.numFrees, (unsigned int)globals.numReallocs);
    fprintf(stderr, "Average allocation size %u bytes\n", (unsigned int)
            (globals.numMallocs != 0 ? globals.totalAlloc/globals.numMallocs: 0));
}

void Memento_stats(void)
{
    fprintf(stderr, "Current memory malloced = %u bytes\n", (unsigned int)globals.alloc);
    Memento_endStats();
}

static void Memento_fin(void)
{
    Memento_checkAllMemory();
    Memento_endStats();
    if (globals.used.head != NULL) {
        Memento_listBlocks();
        Memento_breakpoint();
    }
    if (globals.segv) {
        fprintf(stderr, "Memory dumped on SEGV while squeezing @ %d\n", globals.failAt);
    } else if (globals.squeezing) {
        if (globals.pattern == 0)
            fprintf(stderr, "Memory squeezing @ %d complete\n", globals.squeezeAt);
        else
            fprintf(stderr, "Memory squeezing @ %d (%d) complete\n", globals.squeezeAt, globals.pattern);
    }
    if (globals.failing)
    {
        fprintf(stderr, "MEMENTO_FAILAT=%d\n", globals.failAt);
        fprintf(stderr, "MEMENTO_PATTERN=%d\n", globals.pattern);
    }
    if (globals.nextFailAt != 0)
    {
        fprintf(stderr, "MEMENTO_NEXTFAILAT=%d\n", globals.nextFailAt);
        fprintf(stderr, "MEMENTO_NEXTPATTERN=%d\n", globals.nextPattern);
    }
}

static void Memento_inited(void)
{
    /* A good place for a breakpoint */
}

static void Memento_init(void)
{
    char *env;
    memset(&globals, 0, sizeof(globals));
    globals.inited    = 1;
    globals.used.head = NULL;
    globals.used.tail = &globals.used.head;
    globals.free.head = NULL;
    globals.free.tail = &globals.free.head;
    globals.sequence  = 0;
    globals.countdown = 1024;

    env = getenv("MEMENTO_FAILAT");
    globals.failAt = (env ? atoi(env) : 0);

    env = getenv("MEMENTO_PARANOIA");
    globals.paranoia = (env ? atoi(env) : 0);
    if (globals.paranoia == 0)
        globals.paranoia = 1024;

    env = getenv("MEMENTO_PARANOIDAT");
    globals.paranoidAt = (env ? atoi(env) : 0);

    env = getenv("MEMENTO_SQUEEZEAT");
    globals.squeezeAt = (env ? atoi(env) : 0);

    env = getenv("MEMENTO_PATTERN");
    globals.pattern = (env ? atoi(env) : 0);

    env = getenv("MEMENTO_MAXMEMORY");
    globals.maxMemory = (env ? atoi(env) : 0);

    atexit(Memento_fin);

    Memento_inited();
}

#ifdef MEMENTO_HAS_FORK
#include <unistd.h>
#include <sys/wait.h>
#ifdef MEMENTO_STACKTRACE_METHOD
#if MEMENTO_STACKTRACE_METHOD == 1
#include <signal.h>
#endif
#endif

/* FIXME: Find some portable way of getting this */
/* MacOSX has 10240, Ubuntu seems to have 256 */
#define OPEN_MAX 10240

/* stashed_map[j] = i means that filedescriptor i-1 was duplicated to j */
int stashed_map[OPEN_MAX];

#ifdef MEMENTO_STACKTRACE_METHOD
#if MEMENTO_STACKTRACE_METHOD == 1
extern size_t backtrace(void **, int);
extern void backtrace_symbols_fd(void **, size_t, int);
#endif
#endif

static void Memento_signal(void)
{
    fprintf(stderr, "SEGV after Memory squeezing @ %d\n", globals.squeezeAt);

#ifdef MEMENTO_STACKTRACE_METHOD
#if MEMENTO_STACKTRACE_METHOD == 1
    {
      void *array[100];
      size_t size;

      size = backtrace(array, 100);
      fprintf(stderr, "------------------------------------------------------------------------\n");
      fprintf(stderr, "Backtrace:\n");
      backtrace_symbols_fd(array, size, 2);
      fprintf(stderr, "------------------------------------------------------------------------\n");
    }
#endif
#endif

    exit(1);
}

static int squeeze(void)
{
    pid_t pid;
    int i, status;

    if (globals.patternBit < 0)
        return 1;
    if (globals.squeezing && globals.patternBit >= MEMENTO_MAXPATTERN)
        return 1;

    if (globals.patternBit == 0)
        globals.squeezeAt = globals.sequence;

    if (!globals.squeezing) {
        fprintf(stderr, "Memory squeezing @ %d\n", globals.squeezeAt);
    } else
        fprintf(stderr, "Memory squeezing @ %d (%x,%x)\n", globals.squeezeAt, globals.pattern, globals.patternBit);

    /* When we fork below, the child is going to snaffle all our file pointers
     * and potentially corrupt them. Let's make copies of all of them before
     * we fork, so we can restore them when we restart. */
    for (i = 0; i < OPEN_MAX; i++) {
        if (stashed_map[i] == 0) {
            int j = dup(i);
            stashed_map[j] = i+1;
        }
    }

    pid = fork();
    if (pid == 0) {
        /* Child */
        signal(SIGSEGV, Memento_signal);
        /* In the child, we always fail the next allocation. */
        if (globals.patternBit == 0) {
            globals.patternBit = 1;
        } else
            globals.patternBit <<= 1;
        globals.squeezing = 1;
        return 1;
    }

    /* In the parent if we hit another allocation, pass it (and record the
     * fact we passed it in the pattern. */
    globals.pattern |= globals.patternBit;
    globals.patternBit <<= 1;

    /* Wait for pid to finish */
    waitpid(pid, &status, 0);

    if (status != 0) {
        fprintf(stderr, "Child status=%d\n", status);
    }

    /* Put the files back */
    for (i = 0; i < OPEN_MAX; i++) {
        if (stashed_map[i] != 0) {
            dup2(i, stashed_map[i]-1);
            close(i);
            stashed_map[i] = 0;
        }
    }

    return 0;
}
#else
#include <signal.h>

static void Memento_signal(void)
{
    globals.segv = 1;
    /* If we just return from this function the SEGV will be unhandled, and
     * we'll launch into whatever JIT debugging system the OS provides. At
     * least fprintf(stderr, something useful first. If MEMENTO_NOJIT is set, then
     * just exit to avoid the JIT (and get the usual atexit handling). */
    if (getenv("MEMENTO_NOJIT"))
        exit(1);
    else
        Memento_fin();
}

int squeeze(void)
{
    fprintf(stderr, "Memento memory squeezing disabled as no fork!\n");
    return 0;
}
#endif

static void Memento_startFailing(void)
{
    if (!globals.failing) {
        fprintf(stderr, "Starting to fail...\n");
        fflush(stderr);
        globals.failing = 1;
        globals.failAt = globals.sequence;
        globals.nextFailAt = globals.sequence+1;
        globals.pattern = 0;
        globals.patternBit = 0;
        signal(SIGSEGV, Memento_signal);
        signal(SIGABRT, Memento_signal);
        Memento_breakpoint();
    }
}

static void Memento_event(void)
{
    globals.sequence++;
    if ((globals.sequence >= globals.paranoidAt) && (globals.paranoidAt != 0)) {
        globals.paranoia = 1;
        globals.countdown = 1;
    }
    if (--globals.countdown == 0) {
        Memento_checkAllMemory();
        globals.countdown = globals.paranoia;
    }

    if (globals.sequence == globals.breakAt) {
        fprintf(stderr, "Breaking at event %d\n", globals.breakAt);
        Memento_breakpoint();
    }
}

int Memento_breakAt(int event)
{
    globals.breakAt = event;
    return event;
}

void *Memento_label(void *ptr, const char *label)
{
    Memento_BlkHeader *block;

    if (ptr == NULL)
        return NULL;
    block = MEMBLK_FROMBLK(ptr);
    VALGRIND_MAKE_MEM_DEFINED(block, sizeof(*block));
    block->label = label;
    VALGRIND_MAKE_MEM_UNDEFINED(block, sizeof(*block));
    return ptr;
}

int Memento_failThisEvent(void)
{
    int failThisOne;

    if (!globals.inited)
        Memento_init();

    Memento_event();

    if ((globals.sequence >= globals.failAt) && (globals.failAt != 0))
        Memento_startFailing();
    if ((globals.sequence >= globals.squeezeAt) && (globals.squeezeAt != 0)) {
        return squeeze();
    }

    if (!globals.failing)
        return 0;
    failThisOne = ((globals.patternBit & globals.pattern) == 0);
    /* If we are failing, and we've reached the end of the pattern and we've
     * still got bits available in the pattern word, and we haven't already
     * set a nextPattern, then extend the pattern. */
    if (globals.failing &&
        ((~(globals.patternBit-1) & globals.pattern) == 0) &&
        (globals.patternBit != 0) &&
        globals.nextPattern == 0)
    {
        /* We'll fail this one, and set the 'next' one to pass it. */
        globals.nextFailAt = globals.failAt;
        globals.nextPattern = globals.pattern | globals.patternBit;
    }
    globals.patternBit = (globals.patternBit ? globals.patternBit << 1 : 1);

    return failThisOne;
}

void *Memento_malloc(size_t s)
{
    Memento_BlkHeader *memblk;
    size_t             smem = MEMBLK_SIZE(s);

    if (Memento_failThisEvent())
        return NULL;

    if (s == 0)
        return NULL;

    globals.numMallocs++;

    if (globals.maxMemory != 0 && globals.alloc + s > globals.maxMemory)
        return NULL;

    memblk = MEMENTO_UNDERLYING_MALLOC(smem);
    if (memblk == NULL)
        return NULL;

    globals.alloc      += s;
    globals.totalAlloc += s;
    if (globals.peakAlloc < globals.alloc)
        globals.peakAlloc = globals.alloc;
#ifndef MEMENTO_LEAKONLY
    memset(MEMBLK_TOBLK(memblk), MEMENTO_ALLOCFILL, s);
#endif
    memblk->rawsize       = s;
    memblk->sequence      = globals.sequence;
    memblk->lastCheckedOK = memblk->sequence;
    memblk->flags         = 0;
    memblk->label         = 0;
    memblk->child         = NULL;
    memblk->sibling       = NULL;
    Memento_addBlockHead(&globals.used, memblk, 0);
    return MEMBLK_TOBLK(memblk);
}

void *Memento_calloc(size_t n, size_t s)
{
    void *block = Memento_malloc(n*s);

    if (block)
        memset(block, 0, n*s);
    return block;
}

static int checkBlock(Memento_BlkHeader *memblk, const char *action)
{
#ifndef MEMENTO_LEAKONLY
    BlkCheckData data;

    memset(&data, 0, sizeof(data));
    Memento_appBlock(&globals.used, Memento_Internal_checkAllocedBlock,
                     &data, memblk);
    if (!data.found) {
        /* Failure! */
        fprintf(stderr, "Attempt to %s block ", action);
        showBlock(memblk, 32);
        Memento_breakpoint();
        return 1;
    } else if (data.preCorrupt || data.postCorrupt) {
        fprintf(stderr, "Block ");
        showBlock(memblk, ' ');
        fprintf(stderr, " found to be corrupted on %s!\n", action);
        if (data.preCorrupt) {
            fprintf(stderr, "Preguard corrupted\n");
        }
        if (data.postCorrupt) {
            fprintf(stderr, "Postguard corrupted\n");
        }
        fprintf(stderr, "Block last checked OK at allocation %d. Now %d.\n",
                memblk->lastCheckedOK, globals.sequence);
        Memento_breakpoint();
        return 1;
    }
#endif
    return 0;
}

void Memento_free(void *blk)
{
    Memento_BlkHeader *memblk;

    if (!globals.inited)
        Memento_init();

    Memento_event();

    if (blk == NULL)
        return;

    memblk = MEMBLK_FROMBLK(blk);
    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    if (checkBlock(memblk, "free"))
        return;

    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    if (memblk->flags & Memento_Flag_BreakOnFree)
        Memento_breakpoint();

    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    globals.alloc -= memblk->rawsize;
    globals.numFrees++;

    Memento_removeBlock(&globals.used, memblk);

    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    if (Memento_Internal_makeSpace(MEMBLK_SIZE(memblk->rawsize))) {
        VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
        VALGRIND_MAKE_MEM_DEFINED(MEMBLK_TOBLK(memblk),
                                  memblk->rawsize + Memento_PostSize);
#ifndef MEMENTO_LEAKONLY
        memset(MEMBLK_TOBLK(memblk), MEMENTO_FREEFILL, memblk->rawsize);
#endif
        Memento_addBlockTail(&globals.free, memblk, 1);
    } else {
        MEMENTO_UNDERLYING_FREE(memblk);
    }
}

void *Memento_realloc(void *blk, size_t newsize)
{
    Memento_BlkHeader *memblk, *newmemblk;
    size_t             newsizemem;
    int                flags;

    if (blk == NULL)
        return Memento_malloc(newsize);
    if (newsize == 0) {
        Memento_free(blk);
        return NULL;
    }

    if (Memento_failThisEvent())
        return NULL;

    memblk     = MEMBLK_FROMBLK(blk);
    if (checkBlock(memblk, "realloc"))
        return NULL;

    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    if (memblk->flags & Memento_Flag_BreakOnRealloc)
        Memento_breakpoint();

    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    if (globals.maxMemory != 0 && globals.alloc - memblk->rawsize + newsize > globals.maxMemory)
        return NULL;

    newsizemem = MEMBLK_SIZE(newsize);
    Memento_removeBlock(&globals.used, memblk);
    VALGRIND_MAKE_MEM_DEFINED(memblk, sizeof(*memblk));
    flags = memblk->flags;
    newmemblk  = MEMENTO_UNDERLYING_REALLOC(memblk, newsizemem);
    if (newmemblk == NULL)
    {
        Memento_addBlockHead(&globals.used, memblk, 2);
        return NULL;
    }
    globals.numReallocs++;
    globals.totalAlloc += newsize;
    globals.alloc      -= newmemblk->rawsize;
    globals.alloc      += newsize;
    if (globals.peakAlloc < globals.alloc)
        globals.peakAlloc = globals.alloc;
    newmemblk->flags = flags;
    if (newmemblk->rawsize < newsize) {
        char *newbytes = ((char *)MEMBLK_TOBLK(newmemblk))+newmemblk->rawsize;
        VALGRIND_MAKE_MEM_DEFINED(newbytes, newsize - newmemblk->rawsize);
#ifndef MEMENTO_LEAKONLY
        memset(newbytes, MEMENTO_ALLOCFILL, newsize - newmemblk->rawsize);
#endif
        VALGRIND_MAKE_MEM_UNDEFINED(newbytes, newsize - newmemblk->rawsize);
    }
    newmemblk->rawsize = newsize;
#ifndef MEMENTO_LEAKONLY
    VALGRIND_MAKE_MEM_DEFINED(newmemblk->preblk, Memento_PreSize);
    memset(newmemblk->preblk, MEMENTO_PREFILL, Memento_PreSize);
    VALGRIND_MAKE_MEM_UNDEFINED(newmemblk->preblk, Memento_PreSize);
    VALGRIND_MAKE_MEM_DEFINED(MEMBLK_POSTPTR(newmemblk), Memento_PostSize);
    memset(MEMBLK_POSTPTR(newmemblk), MEMENTO_POSTFILL, Memento_PostSize);
    VALGRIND_MAKE_MEM_UNDEFINED(MEMBLK_POSTPTR(newmemblk), Memento_PostSize);
#endif
    Memento_addBlockHead(&globals.used, newmemblk, 2);
    return MEMBLK_TOBLK(newmemblk);
}

int Memento_checkBlock(void *blk)
{
    Memento_BlkHeader *memblk;

    if (blk == NULL)
        return 0;
    memblk = MEMBLK_FROMBLK(blk);
    return checkBlock(memblk, "check");
}

static int Memento_Internal_checkAllAlloced(Memento_BlkHeader *memblk, void *arg)
{
    BlkCheckData *data = (BlkCheckData *)arg;

    Memento_Internal_checkAllocedBlock(memblk, data);
    if (data->preCorrupt || data->postCorrupt) {
        if ((data->found & 2) == 0) {
            fprintf(stderr, "Allocated blocks:\n");
            data->found |= 2;
        }
        fprintf(stderr, "  Block ");
        showBlock(memblk, ' ');
        if (data->preCorrupt) {
            fprintf(stderr, " Preguard ");
        }
        if (data->postCorrupt) {
            fprintf(stderr, "%s Postguard ",
                    (data->preCorrupt ? "&" : ""));
        }
        fprintf(stderr, "corrupted.\n    "
                "Block last checked OK at allocation %d. Now %d.\n",
                memblk->lastCheckedOK, globals.sequence);
        data->preCorrupt  = 0;
        data->postCorrupt = 0;
        data->freeCorrupt = 0;
    }
    else
        memblk->lastCheckedOK = globals.sequence;
    return 0;
}

static int Memento_Internal_checkAllFreed(Memento_BlkHeader *memblk, void *arg)
{
    BlkCheckData *data = (BlkCheckData *)arg;

    Memento_Internal_checkFreedBlock(memblk, data);
    if (data->preCorrupt || data->postCorrupt || data->freeCorrupt) {
        if ((data->found & 4) == 0) {
            fprintf(stderr, "Freed blocks:\n");
            data->found |= 4;
        }
        fprintf(stderr, "  ");
        showBlock(memblk, ' ');
        if (data->freeCorrupt) {
            fprintf(stderr, " index %d (address 0x%p) onwards", data->index,
                    &((char *)MEMBLK_TOBLK(memblk))[data->index]);
            if (data->preCorrupt) {
                fprintf(stderr, "+ preguard");
            }
            if (data->postCorrupt) {
                fprintf(stderr, "+ postguard");
            }
        } else {
            if (data->preCorrupt) {
                fprintf(stderr, " preguard");
            }
            if (data->postCorrupt) {
                fprintf(stderr, "%s Postguard",
                        (data->preCorrupt ? "+" : ""));
            }
        }
        fprintf(stderr, " corrupted.\n"
                "    Block last checked OK at allocation %d. Now %d.\n",
                memblk->lastCheckedOK, globals.sequence);
        data->preCorrupt  = 0;
        data->postCorrupt = 0;
        data->freeCorrupt = 0;
    }
    else
        memblk->lastCheckedOK = globals.sequence;
    return 0;
}

int Memento_checkAllMemory(void)
{
#ifndef MEMENTO_LEAKONLY
    BlkCheckData data;

    memset(&data, 0, sizeof(data));
    Memento_appBlocks(&globals.used, Memento_Internal_checkAllAlloced, &data);
    Memento_appBlocks(&globals.free, Memento_Internal_checkAllFreed, &data);
    if (data.found & 6) {
        Memento_breakpoint();
        return 1;
    }
#endif
    return 0;
}

int Memento_setParanoia(int i)
{
    globals.paranoia = i;
    globals.countdown = globals.paranoia;
    return i;
}

int Memento_paranoidAt(int i)
{
    globals.paranoidAt = i;
    return i;
}

int Memento_getBlockNum(void *b)
{
    Memento_BlkHeader *memblk;
    if (b == NULL)
        return 0;
    memblk = MEMBLK_FROMBLK(b);
    return (memblk->sequence);
}

int Memento_check(void)
{
    int result;

    fprintf(stderr, "Checking memory\n");
    result = Memento_checkAllMemory();
    fprintf(stderr, "Memory checked!\n");
    return result;
}

typedef struct findBlkData {
    void              *addr;
    Memento_BlkHeader *blk;
    int                flags;
} findBlkData;

static int Memento_containsAddr(Memento_BlkHeader *b,
                                void *arg)
{
    findBlkData *data = (findBlkData *)arg;
    char *blkend = &((char *)MEMBLK_TOBLK(b))[b->rawsize];
    if ((MEMBLK_TOBLK(b) <= data->addr) &&
        ((void *)blkend > data->addr)) {
        data->blk = b;
        data->flags = 1;
        return 1;
    }
    if (((void *)b <= data->addr) &&
        (MEMBLK_TOBLK(b) > data->addr)) {
        data->blk = b;
        data->flags = 2;
        return 1;
    }
    if (((void *)blkend <= data->addr) &&
        ((void *)(blkend + Memento_PostSize) > data->addr)) {
        data->blk = b;
        data->flags = 3;
        return 1;
    }
    return 0;
}

int Memento_find(void *a)
{
    findBlkData data;

    data.addr  = a;
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.used, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Address 0x%p is in %sallocated block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, "\n");
        return data.blk->sequence;
    }
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.free, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Address 0x%p is in %sfreed block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, "\n");
        return data.blk->sequence;
    }
    return 0;
}

void Memento_breakOnFree(void *a)
{
    findBlkData data;

    data.addr  = a;
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.used, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Will stop when address 0x%p (in %sallocated block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, ") is freed\n");
        data.blk->flags |= Memento_Flag_BreakOnFree;
        return;
    }
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.free, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Can't stop on free; address 0x%p is in %sfreed block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, "\n");
        return;
    }
    fprintf(stderr, "Can't stop on free; address 0x%p is not in a known block.\n", a);
}

void Memento_breakOnRealloc(void *a)
{
    findBlkData data;

    data.addr  = a;
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.used, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Will stop when address 0x%p (in %sallocated block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, ") is freed (or realloced)\n");
        data.blk->flags |= Memento_Flag_BreakOnFree | Memento_Flag_BreakOnRealloc;
        return;
    }
    data.blk   = NULL;
    data.flags = 0;
    Memento_appBlocks(&globals.free, Memento_containsAddr, &data);
    if (data.blk != NULL) {
        fprintf(stderr, "Can't stop on free/realloc; address 0x%p is in %sfreed block ",
                data.addr,
                (data.flags == 1 ? "" : (data.flags == 2 ?
                                         "preguard of " : "postguard of ")));
        showBlock(data.blk, ' ');
        fprintf(stderr, "\n");
        return;
    }
    fprintf(stderr, "Can't stop on free/realloc; address 0x%p is not in a known block.\n", a);
}

int Memento_failAt(int i)
{
    globals.failAt = i;
    if ((globals.sequence > globals.failAt) &&
        (globals.failing != 0))
        Memento_startFailing();
    return i;
}

size_t Memento_setMax(size_t max)
{
    globals.maxMemory = max;
    return max;
}

#else

/* Just in case anyone has left some debugging code in... */
void (Memento_breakpoint)(void)
{
}

int (Memento_checkBlock)(void *b)
{
    return 0;
}

int (Memento_checkAllMemory)(void)
{
    return 0;
}

int (Memento_check)(void)
{
    return 0;
}

int (Memento_setParanoia)(int i)
{
    return 0;
}

int (Memento_paranoidAt)(int i)
{
    return 0;
}

int (Memento_breakAt)(int i)
{
    return 0;
}

int  (Memento_getBlockNum)(void *i)
{
    return 0;
}

int (Memento_find)(void *a)
{
    return 0;
}

int (Memento_failAt)(int i)
{
    return 0;
}

void (Memento_breakOnFree)(void *a)
{
}

void (Memento_breakOnRealloc)(void *a)
{
}

#undef Memento_malloc
#undef Memento_free
#undef Memento_realloc
#undef Memento_calloc

void *Memento_malloc(size_t size)
{
    return MEMENTO_UNDERLYING_MALLOC(size);
}

void Memento_free(void *b)
{
    MEMENTO_UNDERLYING_FREE(b);
}

void *Memento_realloc(void *b, size_t s)
{
    return MEMENTO_UNDERLYING_REALLOC(b, s);
}

void *Memento_calloc(size_t n, size_t s)
{
    return MEMENTO_UNDERLYING_CALLOC(n, s);
}

void (Memento_listBlocks)(void)
{
}

void (Memento_listNewBlocks)(void)
{
}

size_t (Memento_setMax)(size_t max)
{
    return 0;
}

void (Memento_stats)(void)
{
}

void *(Memento_label)(void *ptr, const char *label)
{
    return ptr;
}

#endif