summaryrefslogtreecommitdiff
path: root/tcl/generic/tclFileName.c
blob: d57aaedefdb761106942238e9a89576a7a686e49 (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
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
/* 
 * tclFileName.c --
 *
 *	This file contains routines for converting file names betwen
 *	native and network form.
 *
 * Copyright (c) 1995-1996 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id$
 */

#include "tclInt.h"
#include "tclPort.h"
#include "tclRegexp.h"

/*
 * This variable indicates whether the cleanup procedure has been
 * registered for this file yet.
 */

static int initialized = 0;

/*
 * The following regular expression matches the root portion of a Windows
 * absolute or volume relative path.  It will match both UNC and drive relative
 * paths.
 */

#define WIN_ROOT_PATTERN "^(([a-zA-Z]:)|[/\\][/\\]+([^/\\]+)[/\\]+([^/\\]+)|([/\\]))([/\\])*"

/*
 * The following regular expression matches the root portion of a Macintosh
 * absolute path.  It will match degenerate Unix-style paths, tilde paths,
 * Unix-style paths, and Mac paths.
 */

#define MAC_ROOT_PATTERN "^((/+([.][.]?/+)*([.][.]?)?)|(~[^:/]*)(/[^:]*)?|(~[^:]*)(:.*)?|/+([.][.]?/+)*([^:/]+)(/[^:]*)?|([^:]+):.*)$"

/*
 * The following variables are used to hold precompiled regular expressions
 * for use in filename matching.
 */

static regexp *winRootPatternPtr = NULL;
static regexp *macRootPatternPtr = NULL;

/*
 * The following variable is set in the TclPlatformInit call to one
 * of: TCL_PLATFORM_UNIX, TCL_PLATFORM_MAC, or TCL_PLATFORM_WINDOWS.
 */

TclPlatformType tclPlatform = TCL_PLATFORM_UNIX;

/*
 * Prototypes for local procedures defined in this file:
 */

static char *		DoTildeSubst _ANSI_ARGS_((Tcl_Interp *interp,
			    char *user, Tcl_DString *resultPtr));
static char *		ExtractWinRoot _ANSI_ARGS_((char *path,
			    Tcl_DString *resultPtr, int offset));
static void		FileNameCleanup _ANSI_ARGS_((ClientData clientData));
static int		SkipToChar _ANSI_ARGS_((char **stringPtr,
			    char *match));
static char *		SplitMacPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));
static char *		SplitWinPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));
static char *		SplitUnixPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));

/*
 *----------------------------------------------------------------------
 *
 * FileNameCleanup --
 *
 *	This procedure is a Tcl_ExitProc used to clean up the static
 *	data structures used in this file.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Deallocates storage used by the procedures in this file.
 *
 *----------------------------------------------------------------------
 */

static void
FileNameCleanup(clientData)
    ClientData clientData;	/* Not used. */
{
    if (winRootPatternPtr != NULL) {
	ckfree((char *)winRootPatternPtr);
        winRootPatternPtr = (regexp *) NULL;
    }
    if (macRootPatternPtr != NULL) {
	ckfree((char *)macRootPatternPtr);
        macRootPatternPtr = (regexp *) NULL;
    }
    initialized = 0;
}

/*
 *----------------------------------------------------------------------
 *
 * ExtractWinRoot --
 *
 *	Matches the root portion of a Windows path and appends it
 *	to the specified Tcl_DString.
 *	
 * Results:
 *	Returns the position in the path immediately after the root
 *	including any trailing slashes.
 *	Appends a cleaned up version of the root to the Tcl_DString
 *	at the specified offest.
 *
 * Side effects:
 *	Modifies the specified Tcl_DString.
 *
 *----------------------------------------------------------------------
 */

static char *
ExtractWinRoot(path, resultPtr, offset)
    char *path;			/* Path to parse. */
    Tcl_DString *resultPtr;	/* Buffer to hold result. */
    int offset;			/* Offset in buffer where result should be
				 * stored. */
{
    int length;

    /*
     * Initialize the path name parser for Windows path names.
     */

    if (winRootPatternPtr == NULL) {
	winRootPatternPtr = TclRegComp(WIN_ROOT_PATTERN);
	if (!initialized) {
	    Tcl_CreateExitHandler(FileNameCleanup, NULL);
	    initialized = 1;
	}
    }

    /*
     * Match the root portion of a Windows path name.
     */

    if (!TclRegExec(winRootPatternPtr, path, path)) {
	return path;
    }

    Tcl_DStringSetLength(resultPtr, offset);

    if (winRootPatternPtr->startp[2] != NULL) {
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[2], 2);
	if (winRootPatternPtr->startp[6] != NULL) {
	    Tcl_DStringAppend(resultPtr, "/", 1);
	}
    } else if (winRootPatternPtr->startp[4] != NULL) {
	Tcl_DStringAppend(resultPtr, "//", 2);
	length = winRootPatternPtr->endp[3]
	    - winRootPatternPtr->startp[3];
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[3], length);
	Tcl_DStringAppend(resultPtr, "/", 1);
	length = winRootPatternPtr->endp[4]
	    - winRootPatternPtr->startp[4];
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[4], length);
    } else {
	Tcl_DStringAppend(resultPtr, "/", 1);
    }
    return winRootPatternPtr->endp[0];
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetPathType --
 *
 *	Determines whether a given path is relative to the current
 *	directory, relative to the current volume, or absolute.
 *
 * Results:
 *	Returns one of TCL_PATH_ABSOLUTE, TCL_PATH_RELATIVE, or
 *	TCL_PATH_VOLUME_RELATIVE.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Tcl_PathType
Tcl_GetPathType(path)
    char *path;
{
    Tcl_PathType type = TCL_PATH_ABSOLUTE;

    switch (tclPlatform) {
   	case TCL_PLATFORM_UNIX:
	    /*
	     * Paths that begin with / or ~ are absolute.
	     */

	    if ((path[0] != '/') && (path[0] != '~')) {
		type = TCL_PATH_RELATIVE;
	    }
	    break;

	case TCL_PLATFORM_MAC:
	    if (path[0] == ':') {
		type = TCL_PATH_RELATIVE;
	    } else if (path[0] != '~') {

		/*
		 * Since we have eliminated the easy cases, use the
		 * root pattern to look for the other types.
		 */

		if (!macRootPatternPtr) {
		    macRootPatternPtr = TclRegComp(MAC_ROOT_PATTERN);
		    if (!initialized) {
			Tcl_CreateExitHandler(FileNameCleanup, NULL);
			initialized = 1;
		    }
		}
		if (!TclRegExec(macRootPatternPtr, path, path)
			|| (macRootPatternPtr->startp[2] != NULL)) {
		    type = TCL_PATH_RELATIVE;
		}
	    }
	    break;
	
	case TCL_PLATFORM_WINDOWS:
	    if (path[0] != '~') {

		/*
		 * Since we have eliminated the easy cases, check for
		 * drive relative paths using the regular expression.
		 */

		if (!winRootPatternPtr) {
		    winRootPatternPtr = TclRegComp(WIN_ROOT_PATTERN);
		    if (!initialized) {
			Tcl_CreateExitHandler(FileNameCleanup, NULL);
			initialized = 1;
		    }
		}
		if (TclRegExec(winRootPatternPtr, path, path)) {
		    if (winRootPatternPtr->startp[5]
			    || (winRootPatternPtr->startp[2]
				    && !(winRootPatternPtr->startp[6]))) {
			type = TCL_PATH_VOLUME_RELATIVE;
		    }
		} else {
		    type = TCL_PATH_RELATIVE;
		}
	    }
	    break;
    }
    return type;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SplitPath --
 *
 *	Split a path into a list of path components.  The first element
 *	of the list will have the same path type as the original path.
 *
 * Results:
 *	Returns a standard Tcl result.  The interpreter result contains
 *	a list of path components.
 *	*argvPtr will be filled in with the address of an array
 *	whose elements point to the elements of path, in order.
 *	*argcPtr will get filled in with the number of valid elements
 *	in the array.  A single block of memory is dynamically allocated
 *	to hold both the argv array and a copy of the path elements.
 *	The caller must eventually free this memory by calling ckfree()
 *	on *argvPtr.  Note:  *argvPtr and *argcPtr are only modified
 *	if the procedure returns normally.
 *
 * Side effects:
 *	Allocates memory.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_SplitPath(path, argcPtr, argvPtr)
    char *path;			/* Pointer to string containing a path. */
    int *argcPtr;		/* Pointer to location to fill in with
				 * the number of elements in the path. */
    char ***argvPtr;		/* Pointer to place to store pointer to array
				 * of pointers to path elements. */
{
    int i, size;
    char *p;
    Tcl_DString buffer;
    Tcl_DStringInit(&buffer);

    /*
     * Perform platform specific splitting.  These routines will leave the
     * result in the specified buffer.  Individual elements are terminated
     * with a null character.
     */

    p = NULL;			/* Needed only to prevent gcc warnings. */
    switch (tclPlatform) {
   	case TCL_PLATFORM_UNIX:
	    p = SplitUnixPath(path, &buffer);
	    break;

	case TCL_PLATFORM_WINDOWS:
	    p = SplitWinPath(path, &buffer);
	    break;
	    
	case TCL_PLATFORM_MAC:
	    p = SplitMacPath(path, &buffer);
	    break;
    }

    /*
     * Compute the number of elements in the result.
     */

    size = Tcl_DStringLength(&buffer);
    *argcPtr = 0;
    for (i = 0; i < size; i++) {
	if (p[i] == '\0') {
	    (*argcPtr)++;
	}
    }
    
    /*
     * Allocate a buffer large enough to hold the contents of the
     * DString plus the argv pointers and the terminating NULL pointer.
     */

    *argvPtr = (char **) ckalloc((unsigned)
	    ((((*argcPtr) + 1) * sizeof(char *)) + size));

    /*
     * Position p after the last argv pointer and copy the contents of
     * the DString.
     */

    p = (char *) &(*argvPtr)[(*argcPtr) + 1];
    memcpy((VOID *) p, (VOID *) Tcl_DStringValue(&buffer), (size_t) size);

    /*
     * Now set up the argv pointers.
     */

    for (i = 0; i < *argcPtr; i++) {
	(*argvPtr)[i] = p;
	while ((*p++) != '\0') {}
    }
    (*argvPtr)[i] = NULL;

    Tcl_DStringFree(&buffer);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitUnixPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Unix paths.
 *
 * Results:
 *	Stores a null separated array of strings in the specified
 *	Tcl_DString.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitUnixPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int length;
    char *p, *elementStart;

    /*
     * Deal with the root directory as a special case.
     */

    if (path[0] == '/') {
	Tcl_DStringAppend(bufPtr, "/", 2);
	p = path+1;
    } else {
	p = path;
    }

    /*
     * Split on slashes.  Embedded elements that start with tilde will be
     * prefixed with "./" so they are not affected by tilde substitution.
     */

    for (;;) {
	elementStart = p;
	while ((*p != '\0') && (*p != '/')) {
	    p++;
	}
	length = p - elementStart;
	if (length > 0) {
	    if ((elementStart[0] == '~') && (elementStart != path)) {
		Tcl_DStringAppend(bufPtr, "./", 2);
	    }
	    Tcl_DStringAppend(bufPtr, elementStart, length);
	    Tcl_DStringAppend(bufPtr, "", 1);
	}
	if (*p++ == '\0') {
	    break;
	}
    }
    return Tcl_DStringValue(bufPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitWinPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Windows paths.
 *
 * Results:
 *	Stores a null separated array of strings in the specified
 *	Tcl_DString.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitWinPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int length;
    char *p, *elementStart;

    p = ExtractWinRoot(path, bufPtr, 0);

    /*
     * Terminate the root portion, if we matched something.
     */

    if (p != path) {
	Tcl_DStringAppend(bufPtr, "", 1);
    }

    /*
     * Split on slashes.  Embedded elements that start with tilde will be
     * prefixed with "./" so they are not affected by tilde substitution.
     */

    do {
	elementStart = p;
	while ((*p != '\0') && (*p != '/') && (*p != '\\')) {
	    p++;
	}
	length = p - elementStart;
	if (length > 0) {
	    if ((elementStart[0] == '~') && (elementStart != path)) {
		Tcl_DStringAppend(bufPtr, "./", 2);
	    }
	    Tcl_DStringAppend(bufPtr, elementStart, length);
	    Tcl_DStringAppend(bufPtr, "", 1);
	}
    } while (*p++ != '\0');

    return Tcl_DStringValue(bufPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitMacPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Macintosh paths.
 *
 * Results:
 *	Returns a newly allocated argv array.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitMacPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int isMac = 0;		/* 1 if is Mac-style, 0 if Unix-style path. */
    int i, length;
    char *p, *elementStart;

    /*
     * Initialize the path name parser for Macintosh path names.
     */

    if (macRootPatternPtr == NULL) {
	macRootPatternPtr = TclRegComp(MAC_ROOT_PATTERN);
	if (!initialized) {
	    Tcl_CreateExitHandler(FileNameCleanup, NULL);
	    initialized = 1;
	}
    }

    /*
     * Match the root portion of a Mac path name.
     */

    i = 0;			/* Needed only to prevent gcc warnings. */
    if (TclRegExec(macRootPatternPtr, path, path) == 1) {
	/*
	 * Treat degenerate absolute paths like / and /../.. as
	 * Mac relative file names for lack of anything else to do.
	 */

	if (macRootPatternPtr->startp[2] != NULL) {
	    Tcl_DStringAppend(bufPtr, ":", 1);
	    Tcl_DStringAppend(bufPtr, path, macRootPatternPtr->endp[0]
		    - macRootPatternPtr->startp[0] + 1);
	    return Tcl_DStringValue(bufPtr);
	}

	if (macRootPatternPtr->startp[5] != NULL) {

	    /*
	     * Unix-style tilde prefixed paths.
	     */

	    isMac = 0;
	    i = 5;
	} else if (macRootPatternPtr->startp[7] != NULL) {

	    /*
	     * Mac-style tilde prefixed paths.
	     */

	    isMac = 1;
	    i = 7;
	} else if (macRootPatternPtr->startp[10] != NULL) {

	    /*
	     * Normal Unix style paths.
	     */

	    isMac = 0;
	    i = 10;
	} else if (macRootPatternPtr->startp[12] != NULL) {

	    /*
	     * Normal Mac style paths.
	     */

	    isMac = 1;
	    i = 12;
	}

	length = macRootPatternPtr->endp[i]
	    - macRootPatternPtr->startp[i];

	/*
	 * Append the element and terminate it with a : and a null.  Note that
	 * we are forcing the DString to contain an extra null at the end.
	 */

	Tcl_DStringAppend(bufPtr, macRootPatternPtr->startp[i], length);
	Tcl_DStringAppend(bufPtr, ":", 2);
	p = macRootPatternPtr->endp[i];
    } else {
	isMac = (strchr(path, ':') != NULL);
	p = path;
    }
    
    if (isMac) {

	/*
	 * p is pointing at the first colon in the path.  There
	 * will always be one, since this is a Mac-style path.
	 */

	elementStart = p++;
	while ((p = strchr(p, ':')) != NULL) {
	    length = p - elementStart;
	    if (length == 1) {
		while (*p == ':') {
		    Tcl_DStringAppend(bufPtr, "::", 3);
		    elementStart = p++;
		}
	    } else {
		/*
		 * If this is a simple component, drop the leading colon.
		 */

		if ((elementStart[1] != '~')
			&& (strchr(elementStart+1, '/') == NULL)) {
		    elementStart++;
		    length--;
		}
		Tcl_DStringAppend(bufPtr, elementStart, length);
		Tcl_DStringAppend(bufPtr, "", 1);
		elementStart = p++;
	    }
	}
	if (elementStart[1] != '\0' || elementStart == path) {
	    if ((elementStart[1] != '~') && (elementStart[1] != '\0')
			&& (strchr(elementStart+1, '/') == NULL)) {
		    elementStart++;
	    }
	    Tcl_DStringAppend(bufPtr, elementStart, -1);
	    Tcl_DStringAppend(bufPtr, "", 1);
	}
    } else {

	/*
	 * Split on slashes, suppress extra /'s, and convert .. to ::. 
	 */

	for (;;) {
	    elementStart = p;
	    while ((*p != '\0') && (*p != '/')) {
		p++;
	    }
	    length = p - elementStart;
	    if (length > 0) {
		if ((length == 1) && (elementStart[0] == '.')) {
		    Tcl_DStringAppend(bufPtr, ":", 2);
		} else if ((length == 2) && (elementStart[0] == '.')
			&& (elementStart[1] == '.')) {
		    Tcl_DStringAppend(bufPtr, "::", 3);
		} else {
		    if (*elementStart == '~') {
			Tcl_DStringAppend(bufPtr, ":", 1);
		    }
		    Tcl_DStringAppend(bufPtr, elementStart, length);
		    Tcl_DStringAppend(bufPtr, "", 1);
		}
	    }
	    if (*p++ == '\0') {
		break;
	    }
	}
    }
    return Tcl_DStringValue(bufPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_JoinPath --
 *
 *	Combine a list of paths in a platform specific manner.
 *
 * Results:
 *	Appends the joined path to the end of the specified
 *	returning a pointer to the resulting string.  Note that
 *	the Tcl_DString must already be initialized.
 *
 * Side effects:
 *	Modifies the Tcl_DString.
 *
 *----------------------------------------------------------------------
 */

char *
Tcl_JoinPath(argc, argv, resultPtr)
    int argc;
    char **argv;
    Tcl_DString *resultPtr;	/* Pointer to previously initialized DString. */
{
    int oldLength, length, i, needsSep;
    Tcl_DString buffer;
    char *p, c, *dest;

    Tcl_DStringInit(&buffer);
    oldLength = Tcl_DStringLength(resultPtr);

    switch (tclPlatform) {
   	case TCL_PLATFORM_UNIX:
	    for (i = 0; i < argc; i++) {
		p = argv[i];
		/*
		 * If the path is absolute, reset the result buffer.
		 * Consume any duplicate leading slashes or a ./ in
		 * front of a tilde prefixed path that isn't at the
		 * beginning of the path.
		 */

		if (*p == '/') {
		    Tcl_DStringSetLength(resultPtr, oldLength);
		    Tcl_DStringAppend(resultPtr, "/", 1);
		    while (*p == '/') {
			p++;
		    }
		} else if (*p == '~') {
		    Tcl_DStringSetLength(resultPtr, oldLength);
		} else if ((Tcl_DStringLength(resultPtr) != oldLength)
			&& (p[0] == '.') && (p[1] == '/')
			&& (p[2] == '~')) {
		    p += 2;
		}

		if (*p == '\0') {
		    continue;
		}

		/*
		 * Append a separator if needed.
		 */

		length = Tcl_DStringLength(resultPtr);
		if ((length != oldLength)
			&& (Tcl_DStringValue(resultPtr)[length-1] != '/')) {
		    Tcl_DStringAppend(resultPtr, "/", 1);
		    length++;
		}

		/*
		 * Append the element, eliminating duplicate and trailing
		 * slashes.
		 */

		Tcl_DStringSetLength(resultPtr, (int) (length + strlen(p)));
		dest = Tcl_DStringValue(resultPtr) + length;
		for (; *p != '\0'; p++) {
		    if (*p == '/') {
			while (p[1] == '/') {
			    p++;
			}
			if (p[1] != '\0') {
			    *dest++ = '/';
			}
		    } else {
			*dest++ = *p;
		    }
		}
		length = dest - Tcl_DStringValue(resultPtr);
		Tcl_DStringSetLength(resultPtr, length);
	    }
	    break;

	case TCL_PLATFORM_WINDOWS:
	    /*
	     * Iterate over all of the components.  If a component is
	     * absolute, then reset the result and start building the
	     * path from the current component on.
	     */

	    for (i = 0; i < argc; i++) {
		p = ExtractWinRoot(argv[i], resultPtr, oldLength);
		length = Tcl_DStringLength(resultPtr);
		
		/*
		 * If the pointer didn't move, then this is a relative path
		 * or a tilde prefixed path.
		 */

		if (p == argv[i]) {
		    /*
		     * Remove the ./ from tilde prefixed elements unless
		     * it is the first component.
		     */

		    if ((length != oldLength)
			    && (p[0] == '.')
			    && ((p[1] == '/') || (p[1] == '\\'))
			    && (p[2] == '~')) {
			p += 2;
		    } else if (*p == '~') {
			Tcl_DStringSetLength(resultPtr, oldLength);
			length = oldLength;
		    }
		}

		if (*p != '\0') {
		    /*
		     * Check to see if we need to append a separator.
		     */

		    
		    if (length != oldLength) {
			c = Tcl_DStringValue(resultPtr)[length-1];
			if ((c != '/') && (c != ':')) {
			    Tcl_DStringAppend(resultPtr, "/", 1);
			}
		    }

		    /*
		     * Append the element, eliminating duplicate and
		     * trailing slashes.
		     */

		    length = Tcl_DStringLength(resultPtr);
		    Tcl_DStringSetLength(resultPtr, (int) (length + strlen(p)));
		    dest = Tcl_DStringValue(resultPtr) + length;
		    for (; *p != '\0'; p++) {
			if ((*p == '/') || (*p == '\\')) {
			    while ((p[1] == '/') || (p[1] == '\\')) {
				p++;
			    }
			    if (p[1] != '\0') {
				*dest++ = '/';
			    }
			} else {
			    *dest++ = *p;
			}
		    }
		    length = dest - Tcl_DStringValue(resultPtr);
		    Tcl_DStringSetLength(resultPtr, length);
		}
	    }
	    break;

	case TCL_PLATFORM_MAC:
	    needsSep = 1;
	    for (i = 0; i < argc; i++) {
		Tcl_DStringSetLength(&buffer, 0);
		p = SplitMacPath(argv[i], &buffer);
		if ((*p != ':') && (*p != '\0')
			&& (strchr(p, ':') != NULL)) {
		    Tcl_DStringSetLength(resultPtr, oldLength);
		    length = strlen(p);
		    Tcl_DStringAppend(resultPtr, p, length);
		    needsSep = 0;
		    p += length+1;
		}

		/*
		 * Now append the rest of the path elements, skipping
		 * : unless it is the first element of the path, and
		 * watching out for :: et al. so we don't end up with
		 * too many colons in the result.
		 */

		for (; *p != '\0'; p += length+1) {
		    if (p[0] == ':' && p[1] == '\0') {
			if (Tcl_DStringLength(resultPtr) != oldLength) {
			    p++;
			} else {
			    needsSep = 0;
			}
		    } else {
			c = p[1];
			if (*p == ':') {
			    if (!needsSep) {
				p++;
			    }
			} else {
			    if (needsSep) {
				Tcl_DStringAppend(resultPtr, ":", 1);
			    }
			}
			needsSep = (c == ':') ? 0 : 1;
		    }
		    length = strlen(p);
		    Tcl_DStringAppend(resultPtr, p, length);
		}
	    }
	    break;
			       
    }
    Tcl_DStringFree(&buffer);
    return Tcl_DStringValue(resultPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_TranslateFileName --
 *
 *	Converts a file name into a form usable by the native system
 *	interfaces.  If the name starts with a tilde, it will produce
 *	a name where the tilde and following characters have been
 *	replaced by the home directory location for the named user.
 *
 * Results:
 *	The result is a pointer to a static string containing
 *	the new name.  If there was an error in processing the
 *	name, then an error message is left in interp->result
 *	and the return value is NULL.  The result will be stored
 *	in bufferPtr; the caller must call Tcl_DStringFree(bufferPtr)
 *	to free the name if the return value was not NULL.
 *
 * Side effects:
 *	Information may be left in bufferPtr.
 *
 *----------------------------------------------------------------------
 */

char *
Tcl_TranslateFileName(interp, name, bufferPtr)
    Tcl_Interp *interp;		/* Interpreter in which to store error
				 * message (if necessary). */
    char *name;			/* File name, which may begin with "~"
				 * (to indicate current user's home directory)
				 * or "~<user>" (to indicate any user's
				 * home directory). */
    Tcl_DString *bufferPtr;	/* May be used to hold result.  Must not hold
				 * anything at the time of the call, and need
				 * not even be initialized. */
{
    register char *p;

    /*
     * Handle tilde substitutions, if needed.
     */

    if (name[0] == '~') {
	int argc, length;
	char **argv;
	Tcl_DString temp;

	Tcl_SplitPath(name, &argc, &argv);
	
	/*
	 * Strip the trailing ':' off of a Mac path
	 * before passing the user name to DoTildeSubst.
	 */

	if (tclPlatform == TCL_PLATFORM_MAC) {
	    length = strlen(argv[0]);
	    argv[0][length-1] = '\0';
	}
	
	Tcl_DStringInit(&temp);
	argv[0] = DoTildeSubst(interp, argv[0]+1, &temp);
	if (argv[0] == NULL) {
	    Tcl_DStringFree(&temp);
	    ckfree((char *)argv);
	    return NULL;
	}
	Tcl_DStringInit(bufferPtr);
	Tcl_JoinPath(argc, argv, bufferPtr);
	Tcl_DStringFree(&temp);
	ckfree((char*)argv);
    } else {
	Tcl_DStringInit(bufferPtr);
	Tcl_JoinPath(1, &name, bufferPtr);
    }

    /*
     * Convert forward slashes to backslashes in Windows paths because
     * some system interfaces don't accept forward slashes.
     */

    if (tclPlatform == TCL_PLATFORM_WINDOWS) {
	for (p = Tcl_DStringValue(bufferPtr); *p != '\0'; p++) {
	    if (*p == '/') {
		*p = '\\';
	    }
	}
    }
    return Tcl_DStringValue(bufferPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * TclGetExtension --
 *
 *	This function returns a pointer to the beginning of the
 *	extension part of a file name.
 *
 * Results:
 *	Returns a pointer into name which indicates where the extension
 *	starts.  If there is no extension, returns NULL.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

char *
TclGetExtension(name)
    char *name;			/* File name to parse. */
{
    char *p, *lastSep;

    /*
     * First find the last directory separator.
     */

    lastSep = NULL;		/* Needed only to prevent gcc warnings. */
    switch (tclPlatform) {
	case TCL_PLATFORM_UNIX:
	    lastSep = strrchr(name, '/');
	    break;

	case TCL_PLATFORM_MAC:
	    if (strchr(name, ':') == NULL) {
		lastSep = strrchr(name, '/');
	    } else {
		lastSep = strrchr(name, ':');
	    }
	    break;

	case TCL_PLATFORM_WINDOWS:
	    lastSep = NULL;
	    for (p = name; *p != '\0'; p++) {
		if (strchr("/\\:", *p) != NULL) {
		    lastSep = p;
		}
	    }
	    break;
    }
    p = strrchr(name, '.');
    if ((p != NULL) && (lastSep != NULL)
	    && (lastSep > p)) {
	p = NULL;
    }

    /*
     * Back up to the first period in a series of contiguous dots.
     * This is needed so foo..o will be split on the first dot.
     */

    if (p != NULL) {
	while ((p > name) && *(p-1) == '.') {
	    p--;
	}
    }
    return p;
}

/*
 *----------------------------------------------------------------------
 *
 * DoTildeSubst --
 *
 *	Given a string following a tilde, this routine returns the
 *	corresponding home directory.
 *
 * Results:
 *	The result is a pointer to a static string containing the home
 *	directory in native format.  If there was an error in processing
 *	the substitution, then an error message is left in interp->result
 *	and the return value is NULL.  On success, the results are appended
 * 	to resultPtr, and the contents of resultPtr are returned.
 *
 * Side effects:
 *	Information may be left in resultPtr.
 *
 *----------------------------------------------------------------------
 */

static char *
DoTildeSubst(interp, user, resultPtr)
    Tcl_Interp *interp;		/* Interpreter in which to store error
				 * message (if necessary). */
    char *user;			/* Name of user whose home directory should be
				 * substituted, or "" for current user. */
    Tcl_DString *resultPtr;	/* May be used to hold result.  Must not hold
				 * anything at the time of the call, and need
				 * not even be initialized. */
{
    char *dir;

    if (*user == '\0') {
	dir = TclGetEnv("HOME");
	if (dir == NULL) {
	    if (interp) {
		Tcl_ResetResult(interp);
		Tcl_AppendResult(interp, "couldn't find HOME environment ",
			"variable to expand path", (char *) NULL);
	    }
	    return NULL;
	}
	Tcl_JoinPath(1, &dir, resultPtr);
    } else {
	
	/* lint, TclGetuserHome() always NULL under windows. */
	if (TclGetUserHome(user, resultPtr) == NULL) {	
	    if (interp) {
		Tcl_ResetResult(interp);
		Tcl_AppendResult(interp, "user \"", user, "\" doesn't exist",
			(char *) NULL);
	    }
	    return NULL;
	}
    }
    return resultPtr->string;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GlobCmd --
 *
 *	This procedure is invoked to process the "glob" Tcl command.
 *	See the user documentation for details on what it does.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	See the user documentation.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
int
Tcl_GlobCmd(dummy, interp, argc, argv)
    ClientData dummy;			/* Not used. */
    Tcl_Interp *interp;			/* Current interpreter. */
    int argc;				/* Number of arguments. */
    char **argv;			/* Argument strings. */
{
    int i, noComplain, firstArg;
    char c;
    int result = TCL_OK;
    Tcl_DString buffer;
    char *separators, *head, *tail;

    noComplain = 0;
    for (firstArg = 1; (firstArg < argc) && (argv[firstArg][0] == '-');
	    firstArg++) {
	if (strcmp(argv[firstArg], "-nocomplain") == 0) {
	    noComplain = 1;
	} else if (strcmp(argv[firstArg], "--") == 0) {
	    firstArg++;
	    break;
	} else {
	    Tcl_AppendResult(interp, "bad switch \"", argv[firstArg],
		    "\": must be -nocomplain or --", (char *) NULL);
	    return TCL_ERROR;
	}
    }
    if (firstArg >= argc) {
	Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		" ?switches? name ?name ...?\"", (char *) NULL);
	return TCL_ERROR;
    }

    Tcl_DStringInit(&buffer);
    separators = NULL;		/* Needed only to prevent gcc warnings. */
    for (i = firstArg; i < argc; i++) {
	switch (tclPlatform) {
	case TCL_PLATFORM_UNIX:
	    separators = "/";
	    break;
	case TCL_PLATFORM_WINDOWS:
	    separators = "/\\:";
	    break;
	case TCL_PLATFORM_MAC:
	    separators = (strchr(argv[i], ':') == NULL) ? "/" : ":";
	    break;
	}

	Tcl_DStringSetLength(&buffer, 0);

	/*
	 * Perform tilde substitution, if needed.
	 */

	if (argv[i][0] == '~') {
	    char *p;

	    /*
	     * Find the first path separator after the tilde.
	     */

	    for (tail = argv[i]; *tail != '\0'; tail++) {
		if (*tail == '\\') {
		    if (strchr(separators, tail[1]) != NULL) {
			break;
		    }
		} else if (strchr(separators, *tail) != NULL) {
		    break;
		}
	    }

	    /*
	     * Determine the home directory for the specified user.  Note that
	     * we don't allow special characters in the user name.
	     */

	    c = *tail;
	    *tail = '\0';
	    p = strpbrk(argv[i]+1, "\\[]*?{}");
	    if (p == NULL) {
		head = DoTildeSubst(interp, argv[i]+1, &buffer);
	    } else {
		if (!noComplain) {
		    Tcl_ResetResult(interp);
		    Tcl_AppendResult(interp, "globbing characters not ",
			    "supported in user names", (char *) NULL);
		}
		head = NULL;
	    }
	    *tail = c;
	    if (head == NULL) {
		if (noComplain) {
		    Tcl_ResetResult(interp);
		    continue;
		} else {
		    result = TCL_ERROR;
		    goto done;
		}
	    }
	    if (head != Tcl_DStringValue(&buffer)) {
		Tcl_DStringAppend(&buffer, head, -1);
	    }
	} else {
	    tail = argv[i];
	}

	result = TclDoGlob(interp, separators, &buffer, tail);
	if (result != TCL_OK) {
	    if (noComplain) {
		/*
		 * We should in fact pass down the nocomplain flag 
		 * or save the interp result or use another mecanism
		 * so the interp result is not mangled on errors in that case.
		 * but that would a bigger change than reasonable for a patch
		 * release.
		 * (see fileName.test 15.2-15.4 for expected behaviour)
		 */
		Tcl_ResetResult(interp);
		result = TCL_OK;
		continue;
	    } else {
		goto done;
	    }
	}
    }

    if ((*interp->result == 0) && !noComplain) {
	char *sep = "";

	Tcl_AppendResult(interp, "no files matched glob pattern",
		(argc == 2) ? " \"" : "s \"", (char *) NULL);
	for (i = firstArg; i < argc; i++) {
	    Tcl_AppendResult(interp, sep, argv[i], (char *) NULL);
	    sep = " ";
	}
	Tcl_AppendResult(interp, "\"", (char *) NULL);
	result = TCL_ERROR;
    }
done:
    Tcl_DStringFree(&buffer);
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * SkipToChar --
 *
 *	This function traverses a glob pattern looking for the next
 *	unquoted occurance of the specified character at the same braces
 *	nesting level.
 *
 * Results:
 *	Updates stringPtr to point to the matching character, or to
 *	the end of the string if nothing matched.  The return value
 *	is 1 if a match was found at the top level, otherwise it is 0.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
SkipToChar(stringPtr, match)
    char **stringPtr;			/* Pointer string to check. */
    char *match;			/* Pointer to character to find. */
{
    int quoted, level;
    register char *p;

    quoted = 0;
    level = 0;

    for (p = *stringPtr; *p != '\0'; p++) {
	if (quoted) {
	    quoted = 0;
	    continue;
	}
	if ((level == 0) && (*p == *match)) {
	    *stringPtr = p;
	    return 1;
	}
	if (*p == '{') {
	    level++;
	} else if (*p == '}') {
	    level--;
	} else if (*p == '\\') {
	    quoted = 1;
	}
    }
    *stringPtr = p;
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * TclDoGlob --
 *
 *	This recursive procedure forms the heart of the globbing
 *	code.  It performs a depth-first traversal of the tree
 *	given by the path name to be globbed.  The directory and
 *	remainder are assumed to be native format paths.
 *
 * Results:
 *	The return value is a standard Tcl result indicating whether
 *	an error occurred in globbing.  After a normal return the
 *	result in interp will be set to hold all of the file names
 *	given by the dir and rem arguments.  After an error the
 *	result in interp will hold an error message.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclDoGlob(interp, separators, headPtr, tail)
    Tcl_Interp *interp;		/* Interpreter to use for error reporting
				 * (e.g. unmatched brace). */
    char *separators;		/* String containing separator characters
				 * that should be used to identify globbing
				 * boundaries. */
    Tcl_DString *headPtr;	/* Completely expanded prefix. */
    char *tail;			/* The unexpanded remainder of the path. */
{
    int baseLength, quoted, count;
    int result = TCL_OK;
    char *p, *openBrace, *closeBrace, *name, *firstSpecialChar, savedChar;
    char lastChar = 0;
    int length = Tcl_DStringLength(headPtr);

    if (length > 0) {
	lastChar = Tcl_DStringValue(headPtr)[length-1];
    }

    /*
     * Consume any leading directory separators, leaving tail pointing
     * just past the last initial separator.
     */

    count = 0;
    name = tail;
    for (; *tail != '\0'; tail++) {
	if ((*tail == '\\') && (strchr(separators, tail[1]) != NULL)) {
	    tail++;
	} else if (strchr(separators, *tail) == NULL) {
	    break;
	}
	count++;
    }

    /*
     * Deal with path separators.  On the Mac, we have to watch out
     * for multiple separators, since they are special in Mac-style
     * paths.
     */

    switch (tclPlatform) {
	case TCL_PLATFORM_MAC:
	    if (*separators == '/') {
		if (((length == 0) && (count == 0))
			|| ((length > 0) && (lastChar != ':'))) {
		    Tcl_DStringAppend(headPtr, ":", 1);
		}
	    } else {
		if (count == 0) {
		    if ((length > 0) && (lastChar != ':')) {
			Tcl_DStringAppend(headPtr, ":", 1);
		    }
		} else {
		    if (lastChar == ':') {
			count--;
		    }
		    while (count-- > 0) {
			Tcl_DStringAppend(headPtr, ":", 1);
		    }
		}
	    }
	    break;
	case TCL_PLATFORM_WINDOWS:
	    /*
	     * If this is a drive relative path, add the colon and the
	     * trailing slash if needed.  Otherwise add the slash if
	     * this is the first absolute element, or a later relative
	     * element.  Add an extra slash if this is a UNC path.
	     */

	    if (*name == ':') {
		Tcl_DStringAppend(headPtr, ":", 1);
		if (count > 1) {
		    Tcl_DStringAppend(headPtr, "/", 1);
		}
	    } else if ((*tail != '\0')
		    && (((length > 0)
			    && (strchr(separators, lastChar) == NULL))
			    || ((length == 0) && (count > 0)))) {
		Tcl_DStringAppend(headPtr, "/", 1);
		if ((length == 0) && (count > 1)) {
		    Tcl_DStringAppend(headPtr, "/", 1);
		}
	    }
	    
	    break;
	case TCL_PLATFORM_UNIX:
	    /*
	     * Add a separator if this is the first absolute element, or
	     * a later relative element.
	     */

	    if ((*tail != '\0')
		    && (((length > 0)
			    && (strchr(separators, lastChar) == NULL))
			    || ((length == 0) && (count > 0)))) {
		Tcl_DStringAppend(headPtr, "/", 1);
	    }
	    break;
    }

    /*
     * Look for the first matching pair of braces or the first
     * directory separator that is not inside a pair of braces.
     */

    openBrace = closeBrace = NULL;
    quoted = 0;
    for (p = tail; *p != '\0'; p++) {
	if (quoted) {
	    quoted = 0;
	} else if (*p == '\\') {
	    quoted = 1;
	    if (strchr(separators, p[1]) != NULL) {
		break;			/* Quoted directory separator. */
	    }
	} else if (strchr(separators, *p) != NULL) {
	    break;			/* Unquoted directory separator. */
	} else if (*p == '{') {
	    openBrace = p;
	    p++;
	    if (SkipToChar(&p, "}")) {
		closeBrace = p;		/* Balanced braces. */
		break;
	    }
	    Tcl_SetResult(interp, "unmatched open-brace in file name",
		    TCL_STATIC);
	    return TCL_ERROR;
	} else if (*p == '}') {
	    Tcl_SetResult(interp, "unmatched close-brace in file name",
		    TCL_STATIC);
	    return TCL_ERROR;
	}
    }

    /*
     * Substitute the alternate patterns from the braces and recurse.
     */

    if (openBrace != NULL) {
	char *element;
	Tcl_DString newName;
	Tcl_DStringInit(&newName);

	/*
	 * For each element within in the outermost pair of braces,
	 * append the element and the remainder to the fixed portion
	 * before the first brace and recursively call TclDoGlob.
	 */

	Tcl_DStringAppend(&newName, tail, openBrace-tail);
	baseLength = Tcl_DStringLength(&newName);
	length = Tcl_DStringLength(headPtr);
	*closeBrace = '\0';
	for (p = openBrace; p != closeBrace; ) {
	    p++;
	    element = p;
	    SkipToChar(&p, ",");
	    Tcl_DStringSetLength(headPtr, length);
	    Tcl_DStringSetLength(&newName, baseLength);
	    Tcl_DStringAppend(&newName, element, p-element);
	    Tcl_DStringAppend(&newName, closeBrace+1, -1);
	    result = TclDoGlob(interp, separators,
		    headPtr, Tcl_DStringValue(&newName));
	    if (result != TCL_OK) {
		break;
	    }
	}
	*closeBrace = '}';
	Tcl_DStringFree(&newName);
	return result;
    }

    /*
     * At this point, there are no more brace substitutions to perform on
     * this path component.  The variable p is pointing at a quoted or
     * unquoted directory separator or the end of the string.  So we need
     * to check for special globbing characters in the current pattern.
     * We avoid modifying tail if p is pointing at the end of the string.
     */

    if (*p != '\0') {
	 savedChar = *p;
	 *p = '\0';
	 firstSpecialChar = strpbrk(tail, "*[]?\\");
	 *p = savedChar;
    } else {
	firstSpecialChar = strpbrk(tail, "*[]?\\");
    }

    if (firstSpecialChar != NULL) {
	/*
	 * Look for matching files in the current directory.  The
	 * implementation of this function is platform specific, but may
	 * recursively call TclDoGlob.  For each file that matches, it will
	 * add the match onto the interp->result, or call TclDoGlob if there
	 * are more characters to be processed.
	 */

	return TclMatchFiles(interp, separators, headPtr, tail, p);
    }
    Tcl_DStringAppend(headPtr, tail, p-tail);
    if (*p != '\0') {
	return TclDoGlob(interp, separators, headPtr, p);
    }

    /*
     * There are no more wildcards in the pattern and no more unprocessed
     * characters in the tail, so now we can construct the path and verify
     * the existence of the file.
     */

    switch (tclPlatform) {
	case TCL_PLATFORM_MAC:
	    if (strchr(Tcl_DStringValue(headPtr), ':') == NULL) {
		Tcl_DStringAppend(headPtr, ":", 1);
	    }
	    name = Tcl_DStringValue(headPtr);
	    if (TclAccess(name, F_OK) == 0) {
		if ((name[1] != '\0') && (strchr(name+1, ':') == NULL)) {
		    Tcl_AppendElement(interp, name+1);
		} else {
		    Tcl_AppendElement(interp, name);
		}
	    }
	    break;
	case TCL_PLATFORM_WINDOWS: {
	    int exists;
	    /*
	     * We need to convert slashes to backslashes before checking
	     * for the existence of the file.  Once we are done, we need
	     * to convert the slashes back.
	     */

	    if (Tcl_DStringLength(headPtr) == 0) {
		if (((*name == '\\') && (name[1] == '/' || name[1] == '\\'))
			|| (*name == '/')) {
		    Tcl_DStringAppend(headPtr, "\\", 1);
		} else {
		    Tcl_DStringAppend(headPtr, ".", 1);
		}
	    } else {
		for (p = Tcl_DStringValue(headPtr); *p != '\0'; p++) {
		    if (*p == '/') {
			*p = '\\';
		    }
		}
	    }
	    name = Tcl_DStringValue(headPtr);
	    exists = (TclAccess(name, F_OK) == 0);
	    for (p = name; *p != '\0'; p++) {
		if (*p == '\\') {
		    *p = '/';
		}
	    }
	    if (exists) {
		Tcl_AppendElement(interp, name);
	    }
	    break;
	}
	case TCL_PLATFORM_UNIX:
	    if (Tcl_DStringLength(headPtr) == 0) {
		if ((*name == '\\' && name[1] == '/') || (*name == '/')) {
		    Tcl_DStringAppend(headPtr, "/", 1);
		} else {
		    Tcl_DStringAppend(headPtr, ".", 1);
		}
	    }
	    name = Tcl_DStringValue(headPtr);
	    if (TclAccess(name, F_OK) == 0) {
		Tcl_AppendElement(interp, name);
	    }
	    break;
    }

    return TCL_OK;
}