summaryrefslogtreecommitdiffstats
path: root/src/gallium/auxiliary/util/u_snprintf.c
blob: 48426abcb7a4cd5239c0e585113d0c2e263dbf7a (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
/*
 * Copyright (c) 1995 Patrick Powell.
 *
 * This code is based on code written by Patrick Powell <papowell@astart.com>.
 * It may be used for any purpose as long as this notice remains intact on all
 * source code distributions.
 */

/*
 * Copyright (c) 2008 Holger Weiss.
 *
 * This version of the code is maintained by Holger Weiss <holger@jhweiss.de>.
 * My changes to the code may freely be used, modified and/or redistributed for
 * any purpose.  It would be nice if additions and fixes to this file (including
 * trivial code cleanups) would be sent back in order to let me include them in
 * the version available at <http://www.jhweiss.de/software/snprintf.html>.
 * However, this is not a requirement for using or redistributing (possibly
 * modified) versions of this file, nor is leaving this notice intact mandatory.
 */

/*
 * History
 *
 * 2008-01-20 Holger Weiss <holger@jhweiss.de> for C99-snprintf 1.1:
 *
 * 	Fixed the detection of infinite floating point values on IRIX (and
 * 	possibly other systems) and applied another few minor cleanups.
 *
 * 2008-01-06 Holger Weiss <holger@jhweiss.de> for C99-snprintf 1.0:
 *
 * 	Added a lot of new features, fixed many bugs, and incorporated various
 * 	improvements done by Andrew Tridgell <tridge@samba.org>, Russ Allbery
 * 	<rra@stanford.edu>, Hrvoje Niksic <hniksic@xemacs.org>, Damien Miller
 * 	<djm@mindrot.org>, and others for the Samba, INN, Wget, and OpenSSH
 * 	projects.  The additions include: support the "e", "E", "g", "G", and
 * 	"F" conversion specifiers (and use conversion style "f" or "F" for the
 * 	still unsupported "a" and "A" specifiers); support the "hh", "ll", "j",
 * 	"t", and "z" length modifiers; support the "#" flag and the (non-C99)
 * 	"'" flag; use localeconv(3) (if available) to get both the current
 * 	locale's decimal point character and the separator between groups of
 * 	digits; fix the handling of various corner cases of field width and
 * 	precision specifications; fix various floating point conversion bugs;
 * 	handle infinite and NaN floating point values; don't attempt to write to
 * 	the output buffer (which may be NULL) if a size of zero was specified;
 * 	check for integer overflow of the field width, precision, and return
 * 	values and during the floating point conversion; use the OUTCHAR() macro
 * 	instead of a function for better performance; provide asprintf(3) and
 * 	vasprintf(3) functions; add new test cases.  The replacement functions
 * 	have been renamed to use an "rpl_" prefix, the function calls in the
 * 	main project (and in this file) must be redefined accordingly for each
 * 	replacement function which is needed (by using Autoconf or other means).
 * 	Various other minor improvements have been applied and the coding style
 * 	was cleaned up for consistency.
 *
 * 2007-07-23 Holger Weiss <holger@jhweiss.de> for Mutt 1.5.13:
 *
 * 	C99 compliant snprintf(3) and vsnprintf(3) functions return the number
 * 	of characters that would have been written to a sufficiently sized
 * 	buffer (excluding the '\0').  The original code simply returned the
 * 	length of the resulting output string, so that's been fixed.
 *
 * 1998-03-05 Michael Elkins <me@mutt.org> for Mutt 0.90.8:
 *
 * 	The original code assumed that both snprintf(3) and vsnprintf(3) were
 * 	missing.  Some systems only have snprintf(3) but not vsnprintf(3), so
 * 	the code is now broken down under HAVE_SNPRINTF and HAVE_VSNPRINTF.
 *
 * 1998-01-27 Thomas Roessler <roessler@does-not-exist.org> for Mutt 0.89i:
 *
 * 	The PGP code was using unsigned hexadecimal formats.  Unfortunately,
 * 	unsigned formats simply didn't work.
 *
 * 1997-10-22 Brandon Long <blong@fiction.net> for Mutt 0.87.1:
 *
 * 	Ok, added some minimal floating point support, which means this probably
 * 	requires libm on most operating systems.  Don't yet support the exponent
 * 	(e,E) and sigfig (g,G).  Also, fmtint() was pretty badly broken, it just
 * 	wasn't being exercised in ways which showed it, so that's been fixed.
 * 	Also, formatted the code to Mutt conventions, and removed dead code left
 * 	over from the original.  Also, there is now a builtin-test, run with:
 * 	gcc -DTEST_SNPRINTF -o snprintf snprintf.c -lm && ./snprintf
 *
 * 2996-09-15 Brandon Long <blong@fiction.net> for Mutt 0.43:
 *
 * 	This was ugly.  It is still ugly.  I opted out of floating point
 * 	numbers, but the formatter understands just about everything from the
 * 	normal C string format, at least as far as I can tell from the Solaris
 * 	2.5 printf(3S) man page.
 */

/*
 * ToDo
 *
 * - Add wide character support.
 * - Add support for "%a" and "%A" conversions.
 * - Create test routines which predefine the expected results.  Our test cases
 *   usually expose bugs in system implementations rather than in ours :-)
 */

/*
 * Usage
 *
 * 1) The following preprocessor macros should be defined to 1 if the feature or
 *    file in question is available on the target system (by using Autoconf or
 *    other means), though basic functionality should be available as long as
 *    HAVE_STDARG_H and HAVE_STDLIB_H are defined correctly:
 *
 *    	HAVE_VSNPRINTF
 *    	HAVE_SNPRINTF
 *    	HAVE_VASPRINTF
 *    	HAVE_ASPRINTF
 *    	HAVE_STDARG_H
 *    	HAVE_STDDEF_H
 *    	HAVE_STDINT_H
 *    	HAVE_STDLIB_H
 *    	HAVE_INTTYPES_H
 *    	HAVE_LOCALE_H
 *    	HAVE_LOCALECONV
 *    	HAVE_LCONV_DECIMAL_POINT
 *    	HAVE_LCONV_THOUSANDS_SEP
 *    	HAVE_LONG_DOUBLE
 *    	HAVE_LONG_LONG_INT
 *    	HAVE_UNSIGNED_LONG_LONG_INT
 *    	HAVE_INTMAX_T
 *    	HAVE_UINTMAX_T
 *    	HAVE_UINTPTR_T
 *    	HAVE_PTRDIFF_T
 *    	HAVE_VA_COPY
 *    	HAVE___VA_COPY
 *
 * 2) The calls to the functions which should be replaced must be redefined
 *    throughout the project files (by using Autoconf or other means):
 *
 *    	#define vsnprintf rpl_vsnprintf
 *    	#define snprintf rpl_snprintf
 *    	#define vasprintf rpl_vasprintf
 *    	#define asprintf rpl_asprintf
 *
 * 3) The required replacement functions should be declared in some header file
 *    included throughout the project files:
 *
 *    	#if HAVE_CONFIG_H
 *    	#include <config.h>
 *    	#endif
 *    	#if HAVE_STDARG_H
 *    	#include <stdarg.h>
 *    	#if !HAVE_VSNPRINTF
 *    	int rpl_vsnprintf(char *, size_t, const char *, va_list);
 *    	#endif
 *    	#if !HAVE_SNPRINTF
 *    	int rpl_snprintf(char *, size_t, const char *, ...);
 *    	#endif
 *    	#if !HAVE_VASPRINTF
 *    	int rpl_vasprintf(char **, const char *, va_list);
 *    	#endif
 *    	#if !HAVE_ASPRINTF
 *    	int rpl_asprintf(char **, const char *, ...);
 *    	#endif
 *    	#endif
 *
 * Autoconf macros for handling step 1 and step 2 are available at
 * <http://www.jhweiss.de/software/snprintf.html>.
 */

#if HAVE_CONFIG_H
#include <config.h>
#else
#ifdef WIN32
#define vsnprintf rpl_vsnprintf
#define snprintf rpl_snprintf
#define HAVE_VSNPRINTF 0
#define HAVE_SNPRINTF 0
#define HAVE_VASPRINTF 1 /* not needed */
#define HAVE_ASPRINTF 1 /* not needed */
#define HAVE_STDARG_H 1
#define HAVE_STDDEF_H 1
#define HAVE_STDINT_H 0
#define HAVE_STDLIB_H 1
#define HAVE_INTTYPES_H 0
#define HAVE_LOCALE_H 0
#define HAVE_LOCALECONV 0
#define HAVE_LCONV_DECIMAL_POINT 0
#define HAVE_LCONV_THOUSANDS_SEP 0
#define HAVE_LONG_DOUBLE 0
#define HAVE_LONG_LONG_INT 1
#define HAVE_UNSIGNED_LONG_LONG_INT 1
#define HAVE_INTMAX_T 0
#define HAVE_UINTMAX_T 0
#define HAVE_UINTPTR_T 1
#define HAVE_PTRDIFF_T 1
#define HAVE_VA_COPY 0
#define HAVE___VA_COPY 0
#else
#define HAVE_VSNPRINTF 1
#define HAVE_SNPRINTF 1
#define HAVE_VASPRINTF 1
#define HAVE_ASPRINTF 1
#endif
#endif	/* HAVE_CONFIG_H */

#if !HAVE_SNPRINTF || !HAVE_VSNPRINTF || !HAVE_ASPRINTF || !HAVE_VASPRINTF
#include <stdio.h>	/* For NULL, size_t, vsnprintf(3), and vasprintf(3). */
#ifdef VA_START
#undef VA_START
#endif	/* defined(VA_START) */
#ifdef VA_SHIFT
#undef VA_SHIFT
#endif	/* defined(VA_SHIFT) */
#if HAVE_STDARG_H
#include <stdarg.h>
#define VA_START(ap, last) va_start(ap, last)
#define VA_SHIFT(ap, value, type) /* No-op for ANSI C. */
#else	/* Assume <varargs.h> is available. */
#include <varargs.h>
#define VA_START(ap, last) va_start(ap)	/* "last" is ignored. */
#define VA_SHIFT(ap, value, type) value = va_arg(ap, type)
#endif	/* HAVE_STDARG_H */

#if !HAVE_VASPRINTF
#if HAVE_STDLIB_H
#include <stdlib.h>	/* For malloc(3). */
#endif	/* HAVE_STDLIB_H */
#ifdef VA_COPY
#undef VA_COPY
#endif	/* defined(VA_COPY) */
#ifdef VA_END_COPY
#undef VA_END_COPY
#endif	/* defined(VA_END_COPY) */
#if HAVE_VA_COPY
#define VA_COPY(dest, src) va_copy(dest, src)
#define VA_END_COPY(ap) va_end(ap)
#elif HAVE___VA_COPY
#define VA_COPY(dest, src) __va_copy(dest, src)
#define VA_END_COPY(ap) va_end(ap)
#else
#define VA_COPY(dest, src) (void)mymemcpy(&dest, &src, sizeof(va_list))
#define VA_END_COPY(ap) /* No-op. */
#define NEED_MYMEMCPY 1
static void *mymemcpy(void *, void *, size_t);
#endif	/* HAVE_VA_COPY */
#endif	/* !HAVE_VASPRINTF */

#if !HAVE_VSNPRINTF
#include <limits.h>	/* For *_MAX. */
#if HAVE_INTTYPES_H
#include <inttypes.h>	/* For intmax_t (if not defined in <stdint.h>). */
#endif	/* HAVE_INTTYPES_H */
#if HAVE_LOCALE_H
#include <locale.h>	/* For localeconv(3). */
#endif	/* HAVE_LOCALE_H */
#if HAVE_STDDEF_H
#include <stddef.h>	/* For ptrdiff_t. */
#endif	/* HAVE_STDDEF_H */
#if HAVE_STDINT_H
#include <stdint.h>	/* For intmax_t. */
#endif	/* HAVE_STDINT_H */

/* Support for unsigned long long int.  We may also need ULLONG_MAX. */
#ifndef ULONG_MAX	/* We may need ULONG_MAX as a fallback. */
#ifdef UINT_MAX
#define ULONG_MAX UINT_MAX
#else
#define ULONG_MAX INT_MAX
#endif	/* defined(UINT_MAX) */
#endif	/* !defined(ULONG_MAX) */
#ifdef ULLONG
#undef ULLONG
#endif	/* defined(ULLONG) */
#if HAVE_UNSIGNED_LONG_LONG_INT
#define ULLONG unsigned long long int
#ifndef ULLONG_MAX
#define ULLONG_MAX ULONG_MAX
#endif	/* !defined(ULLONG_MAX) */
#else
#define ULLONG unsigned long int
#ifdef ULLONG_MAX
#undef ULLONG_MAX
#endif	/* defined(ULLONG_MAX) */
#define ULLONG_MAX ULONG_MAX
#endif	/* HAVE_LONG_LONG_INT */

/* Support for uintmax_t.  We also need UINTMAX_MAX. */
#ifdef UINTMAX_T
#undef UINTMAX_T
#endif	/* defined(UINTMAX_T) */
#if HAVE_UINTMAX_T || defined(uintmax_t)
#define UINTMAX_T uintmax_t
#ifndef UINTMAX_MAX
#define UINTMAX_MAX ULLONG_MAX
#endif	/* !defined(UINTMAX_MAX) */
#else
#define UINTMAX_T ULLONG
#ifdef UINTMAX_MAX
#undef UINTMAX_MAX
#endif	/* defined(UINTMAX_MAX) */
#define UINTMAX_MAX ULLONG_MAX
#endif	/* HAVE_UINTMAX_T || defined(uintmax_t) */

/* Support for long double. */
#ifndef LDOUBLE
#if HAVE_LONG_DOUBLE
#define LDOUBLE long double
#else
#define LDOUBLE double
#endif	/* HAVE_LONG_DOUBLE */
#endif	/* !defined(LDOUBLE) */

/* Support for long long int. */
#ifndef LLONG
#if HAVE_LONG_LONG_INT
#define LLONG long long int
#else
#define LLONG long int
#endif	/* HAVE_LONG_LONG_INT */
#endif	/* !defined(LLONG) */

/* Support for intmax_t. */
#ifndef INTMAX_T
#if HAVE_INTMAX_T || defined(intmax_t)
#define INTMAX_T intmax_t
#else
#define INTMAX_T LLONG
#endif	/* HAVE_INTMAX_T || defined(intmax_t) */
#endif	/* !defined(INTMAX_T) */

/* Support for uintptr_t. */
#ifndef UINTPTR_T
#if HAVE_UINTPTR_T || defined(uintptr_t)
#define UINTPTR_T uintptr_t
#else
#define UINTPTR_T unsigned long int
#endif	/* HAVE_UINTPTR_T || defined(uintptr_t) */
#endif	/* !defined(UINTPTR_T) */

/* Support for ptrdiff_t. */
#ifndef PTRDIFF_T
#if HAVE_PTRDIFF_T || defined(ptrdiff_t)
#define PTRDIFF_T ptrdiff_t
#else
#define PTRDIFF_T long int
#endif	/* HAVE_PTRDIFF_T || defined(ptrdiff_t) */
#endif	/* !defined(PTRDIFF_T) */

/*
 * We need an unsigned integer type corresponding to ptrdiff_t (cf. C99:
 * 7.19.6.1, 7).  However, we'll simply use PTRDIFF_T and convert it to an
 * unsigned type if necessary.  This should work just fine in practice.
 */
#ifndef UPTRDIFF_T
#define UPTRDIFF_T PTRDIFF_T
#endif	/* !defined(UPTRDIFF_T) */

/*
 * We need a signed integer type corresponding to size_t (cf. C99: 7.19.6.1, 7).
 * However, we'll simply use size_t and convert it to a signed type if
 * necessary.  This should work just fine in practice.
 */
#ifndef SSIZE_T
#define SSIZE_T size_t
#endif	/* !defined(SSIZE_T) */

/* Either ERANGE or E2BIG should be available everywhere. */
#ifndef ERANGE
#define ERANGE E2BIG
#endif	/* !defined(ERANGE) */
#ifndef EOVERFLOW
#define EOVERFLOW ERANGE
#endif	/* !defined(EOVERFLOW) */

/*
 * Buffer size to hold the octal string representation of UINT128_MAX without
 * nul-termination ("3777777777777777777777777777777777777777777").
 */
#ifdef MAX_CONVERT_LENGTH
#undef MAX_CONVERT_LENGTH
#endif	/* defined(MAX_CONVERT_LENGTH) */
#define MAX_CONVERT_LENGTH      43

/* Format read states. */
#define PRINT_S_DEFAULT         0
#define PRINT_S_FLAGS           1
#define PRINT_S_WIDTH           2
#define PRINT_S_DOT             3
#define PRINT_S_PRECISION       4
#define PRINT_S_MOD             5
#define PRINT_S_CONV            6

/* Format flags. */
#define PRINT_F_MINUS           (1 << 0)
#define PRINT_F_PLUS            (1 << 1)
#define PRINT_F_SPACE           (1 << 2)
#define PRINT_F_NUM             (1 << 3)
#define PRINT_F_ZERO            (1 << 4)
#define PRINT_F_QUOTE           (1 << 5)
#define PRINT_F_UP              (1 << 6)
#define PRINT_F_UNSIGNED        (1 << 7)
#define PRINT_F_TYPE_G          (1 << 8)
#define PRINT_F_TYPE_E          (1 << 9)

/* Conversion flags. */
#define PRINT_C_CHAR            1
#define PRINT_C_SHORT           2
#define PRINT_C_LONG            3
#define PRINT_C_LLONG           4
#define PRINT_C_LDOUBLE         5
#define PRINT_C_SIZE            6
#define PRINT_C_PTRDIFF         7
#define PRINT_C_INTMAX          8

#ifndef MAX
#define MAX(x, y) ((x >= y) ? x : y)
#endif	/* !defined(MAX) */
#ifndef CHARTOINT
#define CHARTOINT(ch) (ch - '0')
#endif	/* !defined(CHARTOINT) */
#ifndef ISDIGIT
#define ISDIGIT(ch) ('0' <= (unsigned char)ch && (unsigned char)ch <= '9')
#endif	/* !defined(ISDIGIT) */
#ifndef ISNAN
#define ISNAN(x) (x != x)
#endif	/* !defined(ISNAN) */
#ifndef ISINF
#define ISINF(x) (x != 0.0 && x + x == x)
#endif	/* !defined(ISINF) */

#ifdef OUTCHAR
#undef OUTCHAR
#endif	/* defined(OUTCHAR) */
#define OUTCHAR(str, len, size, ch)                                          \
do {                                                                         \
	if (len + 1 < size)                                                  \
		str[len] = ch;                                               \
	(len)++;                                                             \
} while (/* CONSTCOND */ 0)

static void fmtstr(char *, size_t *, size_t, const char *, int, int, int);
static void fmtint(char *, size_t *, size_t, INTMAX_T, int, int, int, int);
static void fmtflt(char *, size_t *, size_t, LDOUBLE, int, int, int, int *);
static void printsep(char *, size_t *, size_t);
static int getnumsep(int);
static int getexponent(LDOUBLE);
static int convert(UINTMAX_T, char *, size_t, int, int);
static UINTMAX_T cast(LDOUBLE);
static UINTMAX_T myround(LDOUBLE);
static LDOUBLE mypow10(int);

int
rpl_vsnprintf(char *str, size_t size, const char *format, va_list args)
{
	LDOUBLE fvalue;
	INTMAX_T value;
	unsigned char cvalue;
	const char *strvalue;
	INTMAX_T *intmaxptr;
	PTRDIFF_T *ptrdiffptr;
	SSIZE_T *sizeptr;
	LLONG *llongptr;
	long int *longptr;
	int *intptr;
	short int *shortptr;
	signed char *charptr;
	size_t len = 0;
	int overflow = 0;
	int base = 0;
	int cflags = 0;
	int flags = 0;
	int width = 0;
	int precision = -1;
	int state = PRINT_S_DEFAULT;
	char ch = *format++;

	/*
	 * C99 says: "If `n' is zero, nothing is written, and `s' may be a null
	 * pointer." (7.19.6.5, 2)  We're forgiving and allow a NULL pointer
	 * even if a size larger than zero was specified.  At least NetBSD's
	 * snprintf(3) does the same, as well as other versions of this file.
	 * (Though some of these versions will write to a non-NULL buffer even
	 * if a size of zero was specified, which violates the standard.)
	 */
	if (str == NULL && size != 0)
		size = 0;

	while (ch != '\0')
		switch (state) {
		case PRINT_S_DEFAULT:
			if (ch == '%')
				state = PRINT_S_FLAGS;
			else
				OUTCHAR(str, len, size, ch);
			ch = *format++;
			break;
		case PRINT_S_FLAGS:
			switch (ch) {
			case '-':
				flags |= PRINT_F_MINUS;
				ch = *format++;
				break;
			case '+':
				flags |= PRINT_F_PLUS;
				ch = *format++;
				break;
			case ' ':
				flags |= PRINT_F_SPACE;
				ch = *format++;
				break;
			case '#':
				flags |= PRINT_F_NUM;
				ch = *format++;
				break;
			case '0':
				flags |= PRINT_F_ZERO;
				ch = *format++;
				break;
			case '\'':	/* SUSv2 flag (not in C99). */
				flags |= PRINT_F_QUOTE;
				ch = *format++;
				break;
			default:
				state = PRINT_S_WIDTH;
				break;
			}
			break;
		case PRINT_S_WIDTH:
			if (ISDIGIT(ch)) {
				ch = CHARTOINT(ch);
				if (width > (INT_MAX - ch) / 10) {
					overflow = 1;
					goto out;
				}
				width = 10 * width + ch;
				ch = *format++;
			} else if (ch == '*') {
				/*
				 * C99 says: "A negative field width argument is
				 * taken as a `-' flag followed by a positive
				 * field width." (7.19.6.1, 5)
				 */
				if ((width = va_arg(args, int)) < 0) {
					flags |= PRINT_F_MINUS;
					width = -width;
				}
				ch = *format++;
				state = PRINT_S_DOT;
			} else
				state = PRINT_S_DOT;
			break;
		case PRINT_S_DOT:
			if (ch == '.') {
				state = PRINT_S_PRECISION;
				ch = *format++;
			} else
				state = PRINT_S_MOD;
			break;
		case PRINT_S_PRECISION:
			if (precision == -1)
				precision = 0;
			if (ISDIGIT(ch)) {
				ch = CHARTOINT(ch);
				if (precision > (INT_MAX - ch) / 10) {
					overflow = 1;
					goto out;
				}
				precision = 10 * precision + ch;
				ch = *format++;
			} else if (ch == '*') {
				/*
				 * C99 says: "A negative precision argument is
				 * taken as if the precision were omitted."
				 * (7.19.6.1, 5)
				 */
				if ((precision = va_arg(args, int)) < 0)
					precision = -1;
				ch = *format++;
				state = PRINT_S_MOD;
			} else
				state = PRINT_S_MOD;
			break;
		case PRINT_S_MOD:
			switch (ch) {
			case 'h':
				ch = *format++;
				if (ch == 'h') {	/* It's a char. */
					ch = *format++;
					cflags = PRINT_C_CHAR;
				} else
					cflags = PRINT_C_SHORT;
				break;
			case 'l':
				ch = *format++;
				if (ch == 'l') {	/* It's a long long. */
					ch = *format++;
					cflags = PRINT_C_LLONG;
				} else
					cflags = PRINT_C_LONG;
				break;
			case 'L':
				cflags = PRINT_C_LDOUBLE;
				ch = *format++;
				break;
			case 'j':
				cflags = PRINT_C_INTMAX;
				ch = *format++;
				break;
			case 't':
				cflags = PRINT_C_PTRDIFF;
				ch = *format++;
				break;
			case 'z':
				cflags = PRINT_C_SIZE;
				ch = *format++;
				break;
			}
			state = PRINT_S_CONV;
			break;
		case PRINT_S_CONV:
			switch (ch) {
			case 'd':
				/* FALLTHROUGH */
			case 'i':
				switch (cflags) {
				case PRINT_C_CHAR:
					value = (signed char)va_arg(args, int);
					break;
				case PRINT_C_SHORT:
					value = (short int)va_arg(args, int);
					break;
				case PRINT_C_LONG:
					value = va_arg(args, long int);
					break;
				case PRINT_C_LLONG:
					value = va_arg(args, LLONG);
					break;
				case PRINT_C_SIZE:
					value = va_arg(args, SSIZE_T);
					break;
				case PRINT_C_INTMAX:
					value = va_arg(args, INTMAX_T);
					break;
				case PRINT_C_PTRDIFF:
					value = va_arg(args, PTRDIFF_T);
					break;
				default:
					value = va_arg(args, int);
					break;
				}
				fmtint(str, &len, size, value, 10, width,
				    precision, flags);
				break;
			case 'X':
				flags |= PRINT_F_UP;
				/* FALLTHROUGH */
			case 'x':
				base = 16;
				/* FALLTHROUGH */
			case 'o':
				if (base == 0)
					base = 8;
				/* FALLTHROUGH */
			case 'u':
				if (base == 0)
					base = 10;
				flags |= PRINT_F_UNSIGNED;
				switch (cflags) {
				case PRINT_C_CHAR:
					value = (unsigned char)va_arg(args,
					    unsigned int);
					break;
				case PRINT_C_SHORT:
					value = (unsigned short int)va_arg(args,
					    unsigned int);
					break;
				case PRINT_C_LONG:
					value = va_arg(args, unsigned long int);
					break;
				case PRINT_C_LLONG:
					value = va_arg(args, ULLONG);
					break;
				case PRINT_C_SIZE:
					value = va_arg(args, size_t);
					break;
				case PRINT_C_INTMAX:
					value = va_arg(args, UINTMAX_T);
					break;
				case PRINT_C_PTRDIFF:
					value = va_arg(args, UPTRDIFF_T);
					break;
				default:
					value = va_arg(args, unsigned int);
					break;
				}
				fmtint(str, &len, size, value, base, width,
				    precision, flags);
				break;
			case 'A':
				/* Not yet supported, we'll use "%F". */
				/* FALLTHROUGH */
			case 'F':
				flags |= PRINT_F_UP;
			case 'a':
				/* Not yet supported, we'll use "%f". */
				/* FALLTHROUGH */
			case 'f':
				if (cflags == PRINT_C_LDOUBLE)
					fvalue = va_arg(args, LDOUBLE);
				else
					fvalue = va_arg(args, double);
				fmtflt(str, &len, size, fvalue, width,
				    precision, flags, &overflow);
				if (overflow)
					goto out;
				break;
			case 'E':
				flags |= PRINT_F_UP;
				/* FALLTHROUGH */
			case 'e':
				flags |= PRINT_F_TYPE_E;
				if (cflags == PRINT_C_LDOUBLE)
					fvalue = va_arg(args, LDOUBLE);
				else
					fvalue = va_arg(args, double);
				fmtflt(str, &len, size, fvalue, width,
				    precision, flags, &overflow);
				if (overflow)
					goto out;
				break;
			case 'G':
				flags |= PRINT_F_UP;
				/* FALLTHROUGH */
			case 'g':
				flags |= PRINT_F_TYPE_G;
				if (cflags == PRINT_C_LDOUBLE)
					fvalue = va_arg(args, LDOUBLE);
				else
					fvalue = va_arg(args, double);
				/*
				 * If the precision is zero, it is treated as
				 * one (cf. C99: 7.19.6.1, 8).
				 */
				if (precision == 0)
					precision = 1;
				fmtflt(str, &len, size, fvalue, width,
				    precision, flags, &overflow);
				if (overflow)
					goto out;
				break;
			case 'c':
				cvalue = (unsigned char)va_arg(args, int);
				OUTCHAR(str, len, size, cvalue);
				break;
			case 's':
				strvalue = va_arg(args, char *);
				fmtstr(str, &len, size, strvalue, width,
				    precision, flags);
				break;
			case 'p':
				/*
				 * C99 says: "The value of the pointer is
				 * converted to a sequence of printing
				 * characters, in an implementation-defined
				 * manner." (C99: 7.19.6.1, 8)
				 */
				if ((strvalue = va_arg(args, void *)) == NULL)
					/*
					 * We use the glibc format.  BSD prints
					 * "0x0", SysV "0".
					 */
					fmtstr(str, &len, size, "(nil)", width,
					    -1, flags);
				else {
					/*
					 * We use the BSD/glibc format.  SysV
					 * omits the "0x" prefix (which we emit
					 * using the PRINT_F_NUM flag).
					 */
					flags |= PRINT_F_NUM;
					flags |= PRINT_F_UNSIGNED;
					fmtint(str, &len, size,
					    (UINTPTR_T)strvalue, 16, width,
					    precision, flags);
				}
				break;
			case 'n':
				switch (cflags) {
				case PRINT_C_CHAR:
					charptr = va_arg(args, signed char *);
					*charptr = (signed char)len;
					break;
				case PRINT_C_SHORT:
					shortptr = va_arg(args, short int *);
					*shortptr = (short int)len;
					break;
				case PRINT_C_LONG:
					longptr = va_arg(args, long int *);
					*longptr = (long int)len;
					break;
				case PRINT_C_LLONG:
					llongptr = va_arg(args, LLONG *);
					*llongptr = (LLONG)len;
					break;
				case PRINT_C_SIZE:
					/*
					 * C99 says that with the "z" length
					 * modifier, "a following `n' conversion
					 * specifier applies to a pointer to a
					 * signed integer type corresponding to
					 * size_t argument." (7.19.6.1, 7)
					 */
					sizeptr = va_arg(args, SSIZE_T *);
					*sizeptr = len;
					break;
				case PRINT_C_INTMAX:
					intmaxptr = va_arg(args, INTMAX_T *);
					*intmaxptr = len;
					break;
				case PRINT_C_PTRDIFF:
					ptrdiffptr = va_arg(args, PTRDIFF_T *);
					*ptrdiffptr = len;
					break;
				default:
					intptr = va_arg(args, int *);
					*intptr = len;
					break;
				}
				break;
			case '%':	/* Print a "%" character verbatim. */
				OUTCHAR(str, len, size, ch);
				break;
			default:	/* Skip other characters. */
				break;
			}
			ch = *format++;
			state = PRINT_S_DEFAULT;
			base = cflags = flags = width = 0;
			precision = -1;
			break;
		}
out:
	if (len < size)
		str[len] = '\0';
	else if (size > 0)
		str[size - 1] = '\0';

	if (overflow || len >= INT_MAX) {
		return -1;
	}
	return (int)len;
}

static void
fmtstr(char *str, size_t *len, size_t size, const char *value, int width,
       int precision, int flags)
{
	int padlen, strln;	/* Amount to pad. */
	int noprecision = (precision == -1);

	if (value == NULL)	/* We're forgiving. */
		value = "(null)";

	/* If a precision was specified, don't read the string past it. */
	for (strln = 0; value[strln] != '\0' &&
	    (noprecision || strln < precision); strln++)
		continue;

	if ((padlen = width - strln) < 0)
		padlen = 0;
	if (flags & PRINT_F_MINUS)	/* Left justify. */
		padlen = -padlen;

	while (padlen > 0) {	/* Leading spaces. */
		OUTCHAR(str, *len, size, ' ');
		padlen--;
	}
	while (*value != '\0' && (noprecision || precision-- > 0)) {
		OUTCHAR(str, *len, size, *value);
		value++;
	}
	while (padlen < 0) {	/* Trailing spaces. */
		OUTCHAR(str, *len, size, ' ');
		padlen++;
	}
}

static void
fmtint(char *str, size_t *len, size_t size, INTMAX_T value, int base, int width,
       int precision, int flags)
{
	UINTMAX_T uvalue;
	char iconvert[MAX_CONVERT_LENGTH];
	char sign = 0;
	char hexprefix = 0;
	int spadlen = 0;	/* Amount to space pad. */
	int zpadlen = 0;	/* Amount to zero pad. */
	int pos;
	int separators = (flags & PRINT_F_QUOTE);
	int noprecision = (precision == -1);

	if (flags & PRINT_F_UNSIGNED)
		uvalue = value;
	else {
		uvalue = (value >= 0) ? value : -value;
		if (value < 0)
			sign = '-';
		else if (flags & PRINT_F_PLUS)	/* Do a sign. */
			sign = '+';
		else if (flags & PRINT_F_SPACE)
			sign = ' ';
	}

	pos = convert(uvalue, iconvert, sizeof(iconvert), base,
	    flags & PRINT_F_UP);

	if (flags & PRINT_F_NUM && uvalue != 0) {
		/*
		 * C99 says: "The result is converted to an `alternative form'.
		 * For `o' conversion, it increases the precision, if and only
		 * if necessary, to force the first digit of the result to be a
		 * zero (if the value and precision are both 0, a single 0 is
		 * printed).  For `x' (or `X') conversion, a nonzero result has
		 * `0x' (or `0X') prefixed to it." (7.19.6.1, 6)
		 */
		switch (base) {
		case 8:
			if (precision <= pos)
				precision = pos + 1;
			break;
		case 16:
			hexprefix = (flags & PRINT_F_UP) ? 'X' : 'x';
			break;
		}
	}

	if (separators)	/* Get the number of group separators we'll print. */
		separators = getnumsep(pos);

	zpadlen = precision - pos - separators;
	spadlen = width                         /* Minimum field width. */
	    - separators                        /* Number of separators. */
	    - MAX(precision, pos)               /* Number of integer digits. */
	    - ((sign != 0) ? 1 : 0)             /* Will we print a sign? */
	    - ((hexprefix != 0) ? 2 : 0);       /* Will we print a prefix? */

	if (zpadlen < 0)
		zpadlen = 0;
	if (spadlen < 0)
		spadlen = 0;

	/*
	 * C99 says: "If the `0' and `-' flags both appear, the `0' flag is
	 * ignored.  For `d', `i', `o', `u', `x', and `X' conversions, if a
	 * precision is specified, the `0' flag is ignored." (7.19.6.1, 6)
	 */
	if (flags & PRINT_F_MINUS)	/* Left justify. */
		spadlen = -spadlen;
	else if (flags & PRINT_F_ZERO && noprecision) {
		zpadlen += spadlen;
		spadlen = 0;
	}
	while (spadlen > 0) {	/* Leading spaces. */
		OUTCHAR(str, *len, size, ' ');
		spadlen--;
	}
	if (sign != 0)	/* Sign. */
		OUTCHAR(str, *len, size, sign);
	if (hexprefix != 0) {	/* A "0x" or "0X" prefix. */
		OUTCHAR(str, *len, size, '0');
		OUTCHAR(str, *len, size, hexprefix);
	}
	while (zpadlen > 0) {	/* Leading zeros. */
		OUTCHAR(str, *len, size, '0');
		zpadlen--;
	}
	while (pos > 0) {	/* The actual digits. */
		pos--;
		OUTCHAR(str, *len, size, iconvert[pos]);
		if (separators > 0 && pos > 0 && pos % 3 == 0)
			printsep(str, len, size);
	}
	while (spadlen < 0) {	/* Trailing spaces. */
		OUTCHAR(str, *len, size, ' ');
		spadlen++;
	}
}

static void
fmtflt(char *str, size_t *len, size_t size, LDOUBLE fvalue, int width,
       int precision, int flags, int *overflow)
{
	LDOUBLE ufvalue;
	UINTMAX_T intpart;
	UINTMAX_T fracpart;
	UINTMAX_T mask;
	const char *infnan = NULL;
	char iconvert[MAX_CONVERT_LENGTH];
	char fconvert[MAX_CONVERT_LENGTH];
	char econvert[4];	/* "e-12" (without nul-termination). */
	char esign = 0;
	char sign = 0;
	int leadfraczeros = 0;
	int exponent = 0;
	int emitpoint = 0;
	int omitzeros = 0;
	int omitcount = 0;
	int padlen = 0;
	int epos = 0;
	int fpos = 0;
	int ipos = 0;
	int separators = (flags & PRINT_F_QUOTE);
	int estyle = (flags & PRINT_F_TYPE_E);
#if HAVE_LOCALECONV && HAVE_LCONV_DECIMAL_POINT
	struct lconv *lc = localeconv();
#endif	/* HAVE_LOCALECONV && HAVE_LCONV_DECIMAL_POINT */

	/*
	 * AIX' man page says the default is 0, but C99 and at least Solaris'
	 * and NetBSD's man pages say the default is 6, and sprintf(3) on AIX
	 * defaults to 6.
	 */
	if (precision == -1)
		precision = 6;

	if (fvalue < 0.0)
		sign = '-';
	else if (flags & PRINT_F_PLUS)	/* Do a sign. */
		sign = '+';
	else if (flags & PRINT_F_SPACE)
		sign = ' ';

	if (ISNAN(fvalue))
		infnan = (flags & PRINT_F_UP) ? "NAN" : "nan";
	else if (ISINF(fvalue))
		infnan = (flags & PRINT_F_UP) ? "INF" : "inf";

	if (infnan != NULL) {
		if (sign != 0)
			iconvert[ipos++] = sign;
		while (*infnan != '\0')
			iconvert[ipos++] = *infnan++;
		fmtstr(str, len, size, iconvert, width, ipos, flags);
		return;
	}

	/* "%e" (or "%E") or "%g" (or "%G") conversion. */
	if (flags & PRINT_F_TYPE_E || flags & PRINT_F_TYPE_G) {
		if (flags & PRINT_F_TYPE_G) {
			/*
			 * For "%g" (and "%G") conversions, the precision
			 * specifies the number of significant digits, which
			 * includes the digits in the integer part.  The
			 * conversion will or will not be using "e-style" (like
			 * "%e" or "%E" conversions) depending on the precision
			 * and on the exponent.  However, the exponent can be
			 * affected by rounding the converted value, so we'll
			 * leave this decision for later.  Until then, we'll
			 * assume that we're going to do an "e-style" conversion
			 * (in order to get the exponent calculated).  For
			 * "e-style", the precision must be decremented by one.
			 */
			precision--;
			/*
			 * For "%g" (and "%G") conversions, trailing zeros are
			 * removed from the fractional portion of the result
			 * unless the "#" flag was specified.
			 */
			if (!(flags & PRINT_F_NUM))
				omitzeros = 1;
		}
		exponent = getexponent(fvalue);
		estyle = 1;
	}

again:
	/*
	 * Sorry, we only support 9, 19, or 38 digits (that is, the number of
	 * digits of the 32-bit, the 64-bit, or the 128-bit UINTMAX_MAX value
	 * minus one) past the decimal point due to our conversion method.
	 */
	switch (sizeof(UINTMAX_T)) {
	case 16:
		if (precision > 38)
			precision = 38;
		break;
	case 8:
		if (precision > 19)
			precision = 19;
		break;
	default:
		if (precision > 9)
			precision = 9;
		break;
	}

	ufvalue = (fvalue >= 0.0) ? fvalue : -fvalue;
	if (estyle)	/* We want exactly one integer digit. */
		ufvalue /= mypow10(exponent);

	if ((intpart = cast(ufvalue)) == UINTMAX_MAX) {
		*overflow = 1;
		return;
	}

	/*
	 * Factor of ten with the number of digits needed for the fractional
	 * part.  For example, if the precision is 3, the mask will be 1000.
	 */
	mask = (UINTMAX_T)mypow10(precision);
	/*
	 * We "cheat" by converting the fractional part to integer by
	 * multiplying by a factor of ten.
	 */
	if ((fracpart = myround(mask * (ufvalue - intpart))) >= mask) {
		/*
		 * For example, ufvalue = 2.99962, intpart = 2, and mask = 1000
		 * (because precision = 3).  Now, myround(1000 * 0.99962) will
		 * return 1000.  So, the integer part must be incremented by one
		 * and the fractional part must be set to zero.
		 */
		intpart++;
		fracpart = 0;
		if (estyle && intpart == 10) {
			/*
			 * The value was rounded up to ten, but we only want one
			 * integer digit if using "e-style".  So, the integer
			 * part must be set to one and the exponent must be
			 * incremented by one.
			 */
			intpart = 1;
			exponent++;
		}
	}

	/*
	 * Now that we know the real exponent, we can check whether or not to
	 * use "e-style" for "%g" (and "%G") conversions.  If we don't need
	 * "e-style", the precision must be adjusted and the integer and
	 * fractional parts must be recalculated from the original value.
	 *
	 * C99 says: "Let P equal the precision if nonzero, 6 if the precision
	 * is omitted, or 1 if the precision is zero.  Then, if a conversion
	 * with style `E' would have an exponent of X:
	 *
	 * - if P > X >= -4, the conversion is with style `f' (or `F') and
	 *   precision P - (X + 1).
	 *
	 * - otherwise, the conversion is with style `e' (or `E') and precision
	 *   P - 1." (7.19.6.1, 8)
	 *
	 * Note that we had decremented the precision by one.
	 */
	if (flags & PRINT_F_TYPE_G && estyle &&
	    precision + 1 > exponent && exponent >= -4) {
		precision -= exponent;
		estyle = 0;
		goto again;
	}

	if (estyle) {
		if (exponent < 0) {
			exponent = -exponent;
			esign = '-';
		} else
			esign = '+';

		/*
		 * Convert the exponent.  The sizeof(econvert) is 4.  So, the
		 * econvert buffer can hold e.g. "e+99" and "e-99".  We don't
		 * support an exponent which contains more than two digits.
		 * Therefore, the following stores are safe.
		 */
		epos = convert(exponent, econvert, 2, 10, 0);
		/*
		 * C99 says: "The exponent always contains at least two digits,
		 * and only as many more digits as necessary to represent the
		 * exponent." (7.19.6.1, 8)
		 */
		if (epos == 1)
			econvert[epos++] = '0';
		econvert[epos++] = esign;
		econvert[epos++] = (flags & PRINT_F_UP) ? 'E' : 'e';
	}

	/* Convert the integer part and the fractional part. */
	ipos = convert(intpart, iconvert, sizeof(iconvert), 10, 0);
	if (fracpart != 0)	/* convert() would return 1 if fracpart == 0. */
		fpos = convert(fracpart, fconvert, sizeof(fconvert), 10, 0);

	leadfraczeros = precision - fpos;

	if (omitzeros) {
		if (fpos > 0)	/* Omit trailing fractional part zeros. */
			while (omitcount < fpos && fconvert[omitcount] == '0')
				omitcount++;
		else {	/* The fractional part is zero, omit it completely. */
			omitcount = precision;
			leadfraczeros = 0;
		}
		precision -= omitcount;
	}

	/*
	 * Print a decimal point if either the fractional part is non-zero
	 * and/or the "#" flag was specified.
	 */
	if (precision > 0 || flags & PRINT_F_NUM)
		emitpoint = 1;
	if (separators)	/* Get the number of group separators we'll print. */
		separators = getnumsep(ipos);

	padlen = width                  /* Minimum field width. */
	    - ipos                      /* Number of integer digits. */
	    - epos                      /* Number of exponent characters. */
	    - precision                 /* Number of fractional digits. */
	    - separators                /* Number of group separators. */
	    - (emitpoint ? 1 : 0)       /* Will we print a decimal point? */
	    - ((sign != 0) ? 1 : 0);    /* Will we print a sign character? */

	if (padlen < 0)
		padlen = 0;

	/*
	 * C99 says: "If the `0' and `-' flags both appear, the `0' flag is
	 * ignored." (7.19.6.1, 6)
	 */
	if (flags & PRINT_F_MINUS)	/* Left justifty. */
		padlen = -padlen;
	else if (flags & PRINT_F_ZERO && padlen > 0) {
		if (sign != 0) {	/* Sign. */
			OUTCHAR(str, *len, size, sign);
			sign = 0;
		}
		while (padlen > 0) {	/* Leading zeros. */
			OUTCHAR(str, *len, size, '0');
			padlen--;
		}
	}
	while (padlen > 0) {	/* Leading spaces. */
		OUTCHAR(str, *len, size, ' ');
		padlen--;
	}
	if (sign != 0)	/* Sign. */
		OUTCHAR(str, *len, size, sign);
	while (ipos > 0) {	/* Integer part. */
		ipos--;
		OUTCHAR(str, *len, size, iconvert[ipos]);
		if (separators > 0 && ipos > 0 && ipos % 3 == 0)
			printsep(str, len, size);
	}
	if (emitpoint) {	/* Decimal point. */
#if HAVE_LOCALECONV && HAVE_LCONV_DECIMAL_POINT
		if (lc->decimal_point != NULL && *lc->decimal_point != '\0')
			OUTCHAR(str, *len, size, *lc->decimal_point);
		else	/* We'll always print some decimal point character. */
#endif	/* HAVE_LOCALECONV && HAVE_LCONV_DECIMAL_POINT */
			OUTCHAR(str, *len, size, '.');
	}
	while (leadfraczeros > 0) {	/* Leading fractional part zeros. */
		OUTCHAR(str, *len, size, '0');
		leadfraczeros--;
	}
	while (fpos > omitcount) {	/* The remaining fractional part. */
		fpos--;
		OUTCHAR(str, *len, size, fconvert[fpos]);
	}
	while (epos > 0) {	/* Exponent. */
		epos--;
		OUTCHAR(str, *len, size, econvert[epos]);
	}
	while (padlen < 0) {	/* Trailing spaces. */
		OUTCHAR(str, *len, size, ' ');
		padlen++;
	}
}

static void
printsep(char *str, size_t *len, size_t size)
{
#if HAVE_LOCALECONV && HAVE_LCONV_THOUSANDS_SEP
	struct lconv *lc = localeconv();
	int i;

	if (lc->thousands_sep != NULL)
		for (i = 0; lc->thousands_sep[i] != '\0'; i++)
			OUTCHAR(str, *len, size, lc->thousands_sep[i]);
	else
#endif	/* HAVE_LOCALECONV && HAVE_LCONV_THOUSANDS_SEP */
		OUTCHAR(str, *len, size, ',');
}

static int
getnumsep(int digits)
{
	int separators = (digits - ((digits % 3 == 0) ? 1 : 0)) / 3;
#if HAVE_LOCALECONV && HAVE_LCONV_THOUSANDS_SEP
	int strln;
	struct lconv *lc = localeconv();

	/* We support an arbitrary separator length (including zero). */
	if (lc->thousands_sep != NULL) {
		for (strln = 0; lc->thousands_sep[strln] != '\0'; strln++)
			continue;
		separators *= strln;
	}
#endif	/* HAVE_LOCALECONV && HAVE_LCONV_THOUSANDS_SEP */
	return separators;
}

static int
getexponent(LDOUBLE value)
{
	LDOUBLE tmp = (value >= 0.0) ? value : -value;
	int exponent = 0;

	/*
	 * We check for 99 > exponent > -99 in order to work around possible
	 * endless loops which could happen (at least) in the second loop (at
	 * least) if we're called with an infinite value.  However, we checked
	 * for infinity before calling this function using our ISINF() macro, so
	 * this might be somewhat paranoid.
	 */
	while (tmp < 1.0 && tmp > 0.0 && --exponent > -99)
		tmp *= 10;
	while (tmp >= 10.0 && ++exponent < 99)
		tmp /= 10;

	return exponent;
}

static int
convert(UINTMAX_T value, char *buf, size_t size, int base, int caps)
{
	const char *digits = caps ? "0123456789ABCDEF" : "0123456789abcdef";
	size_t pos = 0;

	/* We return an unterminated buffer with the digits in reverse order. */
	do {
		buf[pos++] = digits[value % base];
		value /= base;
	} while (value != 0 && pos < size);

	return (int)pos;
}

static UINTMAX_T
cast(LDOUBLE value)
{
	UINTMAX_T result;

	/*
	 * We check for ">=" and not for ">" because if UINTMAX_MAX cannot be
	 * represented exactly as an LDOUBLE value (but is less than LDBL_MAX),
	 * it may be increased to the nearest higher representable value for the
	 * comparison (cf. C99: 6.3.1.4, 2).  It might then equal the LDOUBLE
	 * value although converting the latter to UINTMAX_T would overflow.
	 */
	if (value >= UINTMAX_MAX)
		return UINTMAX_MAX;

	result = (UINTMAX_T)value;
	/*
	 * At least on NetBSD/sparc64 3.0.2 and 4.99.30, casting long double to
	 * an integer type converts e.g. 1.9 to 2 instead of 1 (which violates
	 * the standard).  Sigh.
	 */
	return (result <= value) ? result : result - 1;
}

static UINTMAX_T
myround(LDOUBLE value)
{
	UINTMAX_T intpart = cast(value);

	return ((value -= intpart) < 0.5) ? intpart : intpart + 1;
}

static LDOUBLE
mypow10(int exponent)
{
	LDOUBLE result = 1;

	while (exponent > 0) {
		result *= 10;
		exponent--;
	}
	while (exponent < 0) {
		result /= 10;
		exponent++;
	}
	return result;
}
#endif	/* !HAVE_VSNPRINTF */

#if !HAVE_VASPRINTF
#if NEED_MYMEMCPY
void *
mymemcpy(void *dst, void *src, size_t len)
{
	const char *from = src;
	char *to = dst;

	/* No need for optimization, we use this only to replace va_copy(3). */
	while (len-- > 0)
		*to++ = *from++;
	return dst;
}
#endif	/* NEED_MYMEMCPY */

int
rpl_vasprintf(char **ret, const char *format, va_list ap)
{
	size_t size;
	int len;
	va_list aq;

	VA_COPY(aq, ap);
	len = vsnprintf(NULL, 0, format, aq);
	VA_END_COPY(aq);
	if (len < 0 || (*ret = malloc(size = len + 1)) == NULL)
		return -1;
	return vsnprintf(*ret, size, format, ap);
}
#endif	/* !HAVE_VASPRINTF */

#if !HAVE_SNPRINTF
#if HAVE_STDARG_H
int
rpl_snprintf(char *str, size_t size, const char *format, ...)
#else
int
rpl_snprintf(va_alist) va_dcl
#endif	/* HAVE_STDARG_H */
{
#if !HAVE_STDARG_H
	char *str;
	size_t size;
	char *format;
#endif	/* HAVE_STDARG_H */
	va_list ap;
	int len;

	VA_START(ap, format);
	VA_SHIFT(ap, str, char *);
	VA_SHIFT(ap, size, size_t);
	VA_SHIFT(ap, format, const char *);
	len = vsnprintf(str, size, format, ap);
	va_end(ap);
	return len;
}
#endif	/* !HAVE_SNPRINTF */

#if !HAVE_ASPRINTF
#if HAVE_STDARG_H
int
rpl_asprintf(char **ret, const char *format, ...)
#else
int
rpl_asprintf(va_alist) va_dcl
#endif	/* HAVE_STDARG_H */
{
#if !HAVE_STDARG_H
	char **ret;
	char *format;
#endif	/* HAVE_STDARG_H */
	va_list ap;
	int len;

	VA_START(ap, format);
	VA_SHIFT(ap, ret, char **);
	VA_SHIFT(ap, format, const char *);
	len = vasprintf(ret, format, ap);
	va_end(ap);
	return len;
}
#endif	/* !HAVE_ASPRINTF */
#else	/* Dummy declaration to avoid empty translation unit warnings. */
int main(void);
#endif	/* !HAVE_SNPRINTF || !HAVE_VSNPRINTF || !HAVE_ASPRINTF || [...] */


/* vim: set joinspaces textwidth=80: */