summaryrefslogtreecommitdiffstats
path: root/generic/tclProc.c
blob: 8bd19d34840a120d4168781305c58e689edc146e (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
/* 
 * tclProc.c --
 *
 *	This file contains routines that implement Tcl procedures,
 *	including the "proc" and "uplevel" commands.
 *
 * Copyright (c) 1987-1993 The Regents of the University of California.
 * Copyright (c) 1994-1996 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * SCCS: %Z% $Id: tclProc.c,v 1.13 1998/08/06 12:15:50 escoffon Exp $ 
 */

#include "tclInt.h"
#include "tclCompile.h"


/*
 *----------------------------------------------------------------------
 *
 * Tcl_ProcObjCmd --
 *
 *	This object-based procedure is invoked to process the "proc" Tcl 
 *	command. See the user documentation for details on what it does.
 *
 * Results:
 *	A standard Tcl object result value.
 *
 * Side effects:
 *	A new procedure gets created.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
int
Tcl_ProcObjCmd(dummy, interp, objc, objv)
    ClientData dummy;		/* Not used. */
    Tcl_Interp *interp;		/* Current interpreter. */
    int objc;			/* Number of arguments. */
    Tcl_Obj *CONST objv[];	/* Argument objects. */
{
    register Interp *iPtr = (Interp *) interp;
    Proc *procPtr;
    char *fullName, *procName;
    Namespace *nsPtr, *altNsPtr, *cxtNsPtr;
    Tcl_Command cmd;
    Tcl_DString ds;
    int result;

    if (objc != 4) {
	Tcl_WrongNumArgs(interp, 1, objv, "name args body");
	return TCL_ERROR;
    }

    /*
     * Determine the namespace where the procedure should reside. Unless
     * the command name includes namespace qualifiers, this will be the
     * current namespace.
     */
    
    fullName = Tcl_GetStringFromObj(objv[1], (int *) NULL);
    result = TclGetNamespaceForQualName(interp, fullName,
	    (Namespace *) NULL, TCL_LEAVE_ERR_MSG,
            &nsPtr, &altNsPtr, &cxtNsPtr, &procName);
    if (result != TCL_OK) {
        return result;
    }
    if (nsPtr == NULL) {
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"can't create procedure \"", fullName,
		"\": unknown namespace", (char *) NULL);
        return TCL_ERROR;
    }
    if (procName == NULL) {
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"can't create procedure \"", fullName,
		"\": bad procedure name", (char *) NULL);
        return TCL_ERROR;
    }
    if ((nsPtr != iPtr->globalNsPtr)
	    && (procName != NULL) && (procName[0] == ':')) {
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"can't create procedure \"", procName,
		"\" in non-global namespace with name starting with \":\"",
	        (char *) NULL);
        return TCL_ERROR;
    }

    /*
     *  Create the data structure to represent the procedure.
     */
    if (TclCreateProc(interp, nsPtr, procName, objv[2], objv[3],
        &procPtr) != TCL_OK) {
        return TCL_ERROR;
    }

    /*
     * Now create a command for the procedure. This will initially be in
     * the current namespace unless the procedure's name included namespace
     * qualifiers. To create the new command in the right namespace, we
     * generate a fully qualified name for it.
     */

    Tcl_DStringInit(&ds);
    if (nsPtr != iPtr->globalNsPtr) {
	Tcl_DStringAppend(&ds, nsPtr->fullName, -1);
	Tcl_DStringAppend(&ds, "::", 2);
    }
    Tcl_DStringAppend(&ds, procName, -1);
    
    Tcl_CreateCommand(interp, Tcl_DStringValue(&ds), TclProcInterpProc,
	    (ClientData) procPtr, TclProcDeleteProc);
    cmd = Tcl_CreateObjCommand(interp, Tcl_DStringValue(&ds),
	    TclObjInterpProc, (ClientData) procPtr, TclProcDeleteProc);

    /*
     * Now initialize the new procedure's cmdPtr field. This will be used
     * later when the procedure is called to determine what namespace the
     * procedure will run in. This will be different than the current
     * namespace if the proc was renamed into a different namespace.
     */
    
    procPtr->cmdPtr = (Command *) cmd;
	
    return TCL_OK;
}


/*
 *----------------------------------------------------------------------
 *
 * TclCreateProc --
 *
 *	Creates the data associated with a Tcl procedure definition.
 *
 * Results:
 *	Returns TCL_OK on success, along with a pointer to a Tcl
 *	procedure definition in procPtrPtr.  This definition should
 *	be freed by calling TclCleanupProc() when it is no longer
 *	needed.  Returns TCL_ERROR if anything goes wrong.
 *
 * Side effects:
 *	If anything goes wrong, this procedure returns an error
 *	message in the interpreter.
 *
 *----------------------------------------------------------------------
 */
int
TclCreateProc(interp, nsPtr, procName, argsPtr, bodyPtr, procPtrPtr)
    Tcl_Interp *interp;         /* interpreter containing proc */
    Namespace *nsPtr;           /* namespace containing this proc */
    char *procName;             /* unqualified name of this proc */
    Tcl_Obj *argsPtr;           /* description of arguments */
    Tcl_Obj *bodyPtr;           /* command body */
    Proc **procPtrPtr;          /* returns:  pointer to proc data */
{
    Interp *iPtr = (Interp*)interp;
    char **argArray = NULL;

    register Proc *procPtr;
    int i, length, result, numArgs;
    char *args, *bytes, *p;
    register CompiledLocal *localPtr;
    Tcl_Obj *defPtr;

    /*
     * If the procedure's body object is shared because its string value is
     * identical to, e.g., the body of another procedure, we must create a
     * private copy for this procedure to use. Such sharing of procedure
     * bodies is rare but can cause problems. A procedure body is compiled
     * in a context that includes the number of compiler-allocated "slots"
     * for local variables. Each formal parameter is given a local variable
     * slot (the "procPtr->numCompiledLocals = numArgs" assignment
     * below). This means that the same code can not be shared by two
     * procedures that have a different number of arguments, even if their
     * bodies are identical. Note that we don't use Tcl_DuplicateObj since
     * we would not want any bytecode internal representation.
     */

    if (Tcl_IsShared(bodyPtr)) {
        bytes = Tcl_GetStringFromObj(bodyPtr, &length);
        bodyPtr = Tcl_NewStringObj(bytes, length);
    }

    /*
     * Create and initialize a Proc structure for the procedure. Note that
     * we initialize its cmdPtr field below after we've created the command
     * for the procedure. We increment the ref count of the procedure's
     * body object since there will be a reference to it in the Proc
     * structure.
     */
    
    Tcl_IncrRefCount(bodyPtr);

    procPtr = (Proc *) ckalloc(sizeof(Proc));
    procPtr->iPtr = iPtr;
    procPtr->refCount = 1;
    procPtr->bodyPtr = bodyPtr;
    procPtr->numArgs  = 0;	/* actual argument count is set below. */
    procPtr->numCompiledLocals = 0;
    procPtr->firstLocalPtr = NULL;
    procPtr->lastLocalPtr = NULL;
    
    /*
     * Break up the argument list into argument specifiers, then process
     * each argument specifier.
     * THIS FAILS IF THE ARG LIST OBJECT'S STRING REP CONTAINS NULLS.
     */

    args = Tcl_GetStringFromObj(argsPtr, &length);
    result = Tcl_SplitList(interp, args, &numArgs, &argArray);
    if (result != TCL_OK) {
	goto procError;
    }
    
    procPtr->numArgs = numArgs;
    procPtr->numCompiledLocals = numArgs;
    for (i = 0;  i < numArgs;  i++) {
	int fieldCount, nameLength, valueLength;
	char **fieldValues;

	/*
	 * Now divide the specifier up into name and default.
	 */

	result = Tcl_SplitList(interp, argArray[i], &fieldCount,
		&fieldValues);
	if (result != TCL_OK) {
	    goto procError;
	}
	if (fieldCount > 2) {
	    ckfree((char *) fieldValues);
	    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		    "too many fields in argument specifier \"",
		    argArray[i], "\"", (char *) NULL);
	    goto procError;
	}
	if ((fieldCount == 0) || (*fieldValues[0] == 0)) {
	    ckfree((char *) fieldValues);
	    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		    "procedure \"", procName,
		    "\" has argument with no name", (char *) NULL);
	    goto procError;
	}
	
	nameLength = strlen(fieldValues[0]);
	if (fieldCount == 2) {
	    valueLength = strlen(fieldValues[1]);
	} else {
	    valueLength = 0;
	}

	/*
	 * Check that the formal parameter name is a scalar.
	 */

	p = fieldValues[0];
	while (*p != '\0') {
	    if (*p == '(') {
		char *q = p;
		do {
		    q++;
		} while (*q != '\0');
		q--;
		if (*q == ')') { /* we have an array element */
		    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		            "procedure \"", procName,
		            "\" has formal parameter \"", fieldValues[0],
			    "\" that is an array element",
			    (char *) NULL);
		    ckfree((char *) fieldValues);
		    goto procError;
		}
	    }
	    p++;
	}

	/*
	 * Allocate an entry in the runtime procedure frame's array of local
	 * variables for the argument. 
	 */

	localPtr = (CompiledLocal *) ckalloc((unsigned) 
	        (sizeof(CompiledLocal) - sizeof(localPtr->name)
		+ nameLength+1));
	if (procPtr->firstLocalPtr == NULL) {
	    procPtr->firstLocalPtr = procPtr->lastLocalPtr = localPtr;
	} else {
	    procPtr->lastLocalPtr->nextPtr = localPtr;
	    procPtr->lastLocalPtr = localPtr;
	}
	localPtr->nextPtr = NULL;
	localPtr->nameLength = nameLength;
	localPtr->frameIndex = i;
	localPtr->isArg  = 1;
	localPtr->isTemp = 0;
	localPtr->flags = VAR_SCALAR;
	localPtr->resolveInfo = NULL;
	
	if (fieldCount == 2) {
	    localPtr->defValuePtr =
		    Tcl_NewStringObj(fieldValues[1], valueLength);
	    Tcl_IncrRefCount(localPtr->defValuePtr);
	} else {
	    localPtr->defValuePtr = NULL;
	}
	strcpy(localPtr->name, fieldValues[0]);
	
	ckfree((char *) fieldValues);
    }

    /*
     * Now initialize the new procedure's cmdPtr field. This will be used
     * later when the procedure is called to determine what namespace the
     * procedure will run in. This will be different than the current
     * namespace if the proc was renamed into a different namespace.
     */
    
    *procPtrPtr = procPtr;
    ckfree((char *) argArray);
    return TCL_OK;

procError:
    Tcl_DecrRefCount(bodyPtr);
    while (procPtr->firstLocalPtr != NULL) {
	localPtr = procPtr->firstLocalPtr;
	procPtr->firstLocalPtr = localPtr->nextPtr;
	
	defPtr = localPtr->defValuePtr;
	if (defPtr != NULL) {
	    Tcl_DecrRefCount(defPtr);
	}
	
	ckfree((char *) localPtr);
    }
    ckfree((char *) procPtr);
    if (argArray != NULL) {
	ckfree((char *) argArray);
    }
    return TCL_ERROR;
}


/*
 *----------------------------------------------------------------------
 *
 * TclGetFrame --
 *
 *	Given a description of a procedure frame, such as the first
 *	argument to an "uplevel" or "upvar" command, locate the
 *	call frame for the appropriate level of procedure.
 *
 * Results:
 *	The return value is -1 if an error occurred in finding the
 *	frame (in this case an error message is left in interp->result).
 *	1 is returned if string was either a number or a number preceded
 *	by "#" and it specified a valid frame.  0 is returned if string
 *	isn't one of the two things above (in this case, the lookup
 *	acts as if string were "1").  The variable pointed to by
 *	framePtrPtr is filled in with the address of the desired frame
 *	(unless an error occurs, in which case it isn't modified).
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclGetFrame(interp, string, framePtrPtr)
    Tcl_Interp *interp;		/* Interpreter in which to find frame. */
    char *string;		/* String describing frame. */
    CallFrame **framePtrPtr;	/* Store pointer to frame here (or NULL
				 * if global frame indicated). */
{
    register Interp *iPtr = (Interp *) interp;
    int curLevel, level, result;
    CallFrame *framePtr;

    /*
     * Parse string to figure out which level number to go to.
     */

    result = 1;
    curLevel = (iPtr->varFramePtr == NULL) ? 0 : iPtr->varFramePtr->level;
    if (*string == '#') {
	if (Tcl_GetInt(interp, string+1, &level) != TCL_OK) {
	    return -1;
	}
	if (level < 0) {
	    levelError:
	    Tcl_AppendResult(interp, "bad level \"", string, "\"",
		    (char *) NULL);
	    return -1;
	}
    } else if (isdigit(UCHAR(*string))) {
	if (Tcl_GetInt(interp, string, &level) != TCL_OK) {
	    return -1;
	}
	level = curLevel - level;
    } else {
	level = curLevel - 1;
	result = 0;
    }

    /*
     * Figure out which frame to use, and modify the interpreter so
     * its variables come from that frame.
     */

    if (level == 0) {
	framePtr = NULL;
    } else {
	for (framePtr = iPtr->varFramePtr; framePtr != NULL;
		framePtr = framePtr->callerVarPtr) {
	    if (framePtr->level == level) {
		break;
	    }
	}
	if (framePtr == NULL) {
	    goto levelError;
	}
    }
    *framePtrPtr = framePtr;
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_UplevelObjCmd --
 *
 *	This object procedure is invoked to process the "uplevel" Tcl
 *	command. See the user documentation for details on what it does.
 *
 * Results:
 *	A standard Tcl object result value.
 *
 * Side effects:
 *	See the user documentation.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
int
Tcl_UplevelObjCmd(dummy, interp, objc, objv)
    ClientData dummy;		/* Not used. */
    Tcl_Interp *interp;		/* Current interpreter. */
    int objc;			/* Number of arguments. */
    Tcl_Obj *CONST objv[];	/* Argument objects. */
{
    register Interp *iPtr = (Interp *) interp;
    char *optLevel;
    int length, result;
    CallFrame *savedVarFramePtr, *framePtr;

    if (objc < 2) {
	uplevelSyntax:
	Tcl_WrongNumArgs(interp, 1, objv, "?level? command ?arg ...?");
	return TCL_ERROR;
    }

    /*
     * Find the level to use for executing the command.
     * THIS FAILS IF THE OBJECT RESULT'S STRING REP CONTAINS A NULL.
     */

    optLevel = Tcl_GetStringFromObj(objv[1], &length);
    result = TclGetFrame(interp, optLevel, &framePtr);
    if (result == -1) {
	return TCL_ERROR;
    }
    objc -= (result+1);
    if (objc == 0) {
	goto uplevelSyntax;
    }
    objv += (result+1);

    /*
     * Modify the interpreter state to execute in the given frame.
     */

    savedVarFramePtr = iPtr->varFramePtr;
    iPtr->varFramePtr = framePtr;

    /*
     * Execute the residual arguments as a command.
     */

    if (objc == 1) {
	result = Tcl_EvalObj(interp, objv[0]);
    } else {
	Tcl_Obj *cmdObjPtr = Tcl_ConcatObj(objc, objv);
	result = Tcl_EvalObj(interp, cmdObjPtr);
	Tcl_DecrRefCount(cmdObjPtr); /* done with object */
    }
    if (result == TCL_ERROR) {
	char msg[60];
	sprintf(msg, "\n    (\"uplevel\" body line %d)", interp->errorLine);
	Tcl_AddObjErrorInfo(interp, msg, -1);
    }

    /*
     * Restore the variable frame, and return.
     */

    iPtr->varFramePtr = savedVarFramePtr;
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TclFindProc --
 *
 *	Given the name of a procedure, return a pointer to the
 *	record describing the procedure.
 *
 * Results:
 *	NULL is returned if the name doesn't correspond to any
 *	procedure.  Otherwise the return value is a pointer to
 *	the procedure's record.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Proc *
TclFindProc(iPtr, procName)
    Interp *iPtr;		/* Interpreter in which to look. */
    char *procName;		/* Name of desired procedure. */
{
    Tcl_Command cmd;
    Tcl_Command origCmd;
    Command *cmdPtr;
    
    cmd = Tcl_FindCommand((Tcl_Interp *) iPtr, procName,
            (Tcl_Namespace *) NULL, /*flags*/ 0);
    if (cmd == (Tcl_Command) NULL) {
        return NULL;
    }
    cmdPtr = (Command *) cmd;

    origCmd = TclGetOriginalCommand(cmd);
    if (origCmd != NULL) {
	cmdPtr = (Command *) origCmd;
    }
    if (cmdPtr->proc != TclProcInterpProc) {
	return NULL;
    }
    return (Proc *) cmdPtr->clientData;
}

/*
 *----------------------------------------------------------------------
 *
 * TclIsProc --
 *
 *	Tells whether a command is a Tcl procedure or not.
 *
 * Results:
 *	If the given command is actually a Tcl procedure, the
 *	return value is the address of the record describing
 *	the procedure.  Otherwise the return value is 0.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Proc *
TclIsProc(cmdPtr)
    Command *cmdPtr;		/* Command to test. */
{
    Tcl_Command origCmd;

    origCmd = TclGetOriginalCommand((Tcl_Command) cmdPtr);
    if (origCmd != NULL) {
	cmdPtr = (Command *) origCmd;
    }
    if (cmdPtr->proc == TclProcInterpProc) {
	return (Proc *) cmdPtr->clientData;
    }
    return (Proc *) 0;
}

/*
 *----------------------------------------------------------------------
 *
 * TclProcInterpProc --
 *
 *	When a Tcl procedure gets invoked with an argc/argv array of
 *	strings, this routine gets invoked to interpret the procedure.
 *
 * Results:
 *	A standard Tcl result value, usually TCL_OK.
 *
 * Side effects:
 *	Depends on the commands in the procedure.
 *
 *----------------------------------------------------------------------
 */

int
TclProcInterpProc(clientData, interp, argc, argv)
    ClientData clientData;	/* Record describing procedure to be
				 * interpreted. */
    Tcl_Interp *interp;		/* Interpreter in which procedure was
				 * invoked. */
    int argc;			/* Count of number of arguments to this
				 * procedure. */
    register char **argv;	/* Argument values. */
{
    register Tcl_Obj *objPtr;
    register int i;
    int result;

    /*
     * This procedure generates an objv array for object arguments that hold
     * the argv strings. It starts out with stack-allocated space but uses
     * dynamically-allocated storage if needed.
     */

#define NUM_ARGS 20
    Tcl_Obj *(objStorage[NUM_ARGS]);
    register Tcl_Obj **objv = objStorage;

    /*
     * Create the object argument array "objv". Make sure objv is large
     * enough to hold the objc arguments plus 1 extra for the zero
     * end-of-objv word.
     */

    if ((argc + 1) > NUM_ARGS) {
	objv = (Tcl_Obj **)
	    ckalloc((unsigned)(argc + 1) * sizeof(Tcl_Obj *));
    }

    for (i = 0;  i < argc;  i++) {
	objv[i] = Tcl_NewStringObj(argv[i], -1);
	Tcl_IncrRefCount(objv[i]);
    }
    objv[argc] = 0;

    /*
     * Use TclObjInterpProc to actually interpret the procedure.
     */

    result = TclObjInterpProc(clientData, interp, argc, objv);

    /*
     * Move the interpreter's object result to the string result, 
     * then reset the object result.
     * FAILS IF OBJECT RESULT'S STRING REPRESENTATION CONTAINS NULLS.
     */
    
    Tcl_SetResult(interp,
	    TclGetStringFromObj(Tcl_GetObjResult(interp), (int *) NULL),
	    TCL_VOLATILE);

    /*
     * Decrement the ref counts on the objv elements since we are done
     * with them.
     */

    for (i = 0;  i < argc;  i++) {
	objPtr = objv[i];
	TclDecrRefCount(objPtr);
    }
    
    /*
     * Free the objv array if malloc'ed storage was used.
     */

    if (objv != objStorage) {
	ckfree((char *) objv);
    }
    return result;
#undef NUM_ARGS
}

/*
 *----------------------------------------------------------------------
 *
 * TclObjInterpProc --
 *
 *	When a Tcl procedure gets invoked during bytecode evaluation, this 
 *	object-based routine gets invoked to interpret the procedure.
 *
 * Results:
 *	A standard Tcl object result value.
 *
 * Side effects:
 *	Depends on the commands in the procedure.
 *
 *----------------------------------------------------------------------
 */

int
TclObjInterpProc(clientData, interp, objc, objv)
    ClientData clientData;	/* Record describing procedure to be
				 * interpreted. */
    Tcl_Interp *interp;		/* Interpreter in which procedure was
				 * invoked. */
    int objc;			/* Count of number of arguments to this
				 * procedure. */
    Tcl_Obj *CONST objv[];	/* Argument value objects. */
{
    Interp *iPtr = (Interp *) interp;
    Proc *procPtr = (Proc *) clientData;
    Namespace *nsPtr = procPtr->cmdPtr->nsPtr;
    CallFrame frame;
    register CallFrame *framePtr = &frame;
    register Var *varPtr, *resolvedVarPtr;
    register CompiledLocal *localPtr;
    Tcl_ResolvedVarInfo *resVarInfo;
    char *procName, *bytes;
    int nameLen, localCt, numArgs, argCt, length, i, result;

    /*
     * This procedure generates an array "compiledLocals" that holds the
     * storage for local variables. It starts out with stack-allocated space
     * but uses dynamically-allocated storage if needed.
     */

#define NUM_LOCALS 20
    Var localStorage[NUM_LOCALS];
    Var *compiledLocals = localStorage;

    /*
     * Get the procedure's name.
     * THIS FAILS IF THE PROC NAME'S STRING REP HAS A NULL.
     */
    
    procName = Tcl_GetStringFromObj(objv[0], &nameLen);

    /*
     * If necessary, compile the procedure's body. The compiler will
     * allocate frame slots for the procedure's non-argument local
     * variables.  Note that compiling the body might increase
     * procPtr->numCompiledLocals if new local variables are found
     * while compiling.
     */
    
    result = TclProcCompileProc(interp, procPtr, procPtr->bodyPtr, nsPtr,
	    "body of proc", procName);
    
    if (result != TCL_OK) {
        return result;
    }

    /*
     * Create the "compiledLocals" array. Make sure it is large enough to
     * hold all the procedure's compiled local variables, including its
     * formal parameters.
     */

    localCt = procPtr->numCompiledLocals;
    if (localCt > NUM_LOCALS) {
	compiledLocals = (Var *) ckalloc((unsigned) localCt * sizeof(Var));
    }
    
    /*
     * Set up and push a new call frame for the new procedure invocation.
     * This call frame will execute in the proc's namespace, which might
     * be different than the current namespace. The proc's namespace is
     * that of its command, which can change if the command is renamed
     * from one namespace to another.
     */

    result = Tcl_PushCallFrame(interp, (Tcl_CallFrame *) framePtr,
            (Tcl_Namespace *) nsPtr, /*isProcCallFrame*/ 1);

    if (result != TCL_OK) {
        return result;
    }

    framePtr->objc = objc;
    framePtr->objv = objv;  /* ref counts for args are incremented below */
    framePtr->procPtr = procPtr;
    framePtr->numCompiledLocals = localCt;
    framePtr->compiledLocals = compiledLocals;

    /*
     * Initialize the array of local variables stored in the call frame.
     * Some variables may have special resolution rules.  In that case,
     * we call their "resolver" procs to get our hands on the variable,
     * and we make the compiled local a link to the real variable.
     */

    varPtr = framePtr->compiledLocals;
    for (localPtr = procPtr->firstLocalPtr;  localPtr != NULL;
	    localPtr = localPtr->nextPtr) {

        resVarInfo = localPtr->resolveInfo;
        resolvedVarPtr = NULL;

        if (resVarInfo && resVarInfo->fetchProc) {
            resolvedVarPtr = (Var*) (*resVarInfo->fetchProc)(interp,
                resVarInfo->identity);
        }

        if (resolvedVarPtr) {
	    varPtr->name = localPtr->name; /* will be just '\0' if temp var */
	    varPtr->nsPtr = NULL;
	    varPtr->hPtr = NULL;
	    varPtr->refCount = 0;
	    varPtr->tracePtr = NULL;
	    varPtr->searchPtr = NULL;
	    varPtr->flags = 0;
            TclSetVarLink(varPtr);
            varPtr->value.linkPtr = resolvedVarPtr;
            resolvedVarPtr->refCount++;
        }
        else {
	    varPtr->value.objPtr = NULL;
	    varPtr->name = localPtr->name; /* will be just '\0' if temp var */
	    varPtr->nsPtr = NULL;
	    varPtr->hPtr = NULL;
	    varPtr->refCount = 0;
	    varPtr->tracePtr = NULL;
	    varPtr->searchPtr = NULL;
	    varPtr->flags = (localPtr->flags | VAR_UNDEFINED);
        }
	varPtr++;
    }

    /*
     * Match and assign the call's actual parameters to the procedure's
     * formal arguments. The formal arguments are described by the first
     * numArgs entries in both the Proc structure's local variable list and
     * the call frame's local variable array.
     */

    numArgs = procPtr->numArgs;
    varPtr = framePtr->compiledLocals;
    localPtr = procPtr->firstLocalPtr;
    argCt = objc;
    for (i = 1, argCt -= 1;  i <= numArgs;  i++, argCt--) {
	if (!localPtr->isArg) {
	    panic("TclObjInterpProc: local variable %s is not argument but should be",
		  localPtr->name);
	    return TCL_ERROR;
	}
	if (localPtr->isTemp) {
	    panic("TclObjInterpProc: local variable %d is temporary but should be an argument", i);
	    return TCL_ERROR;
	}

	/*
	 * Handle the special case of the last formal being "args".  When
	 * it occurs, assign it a list consisting of all the remaining
	 * actual arguments.
	 */

	if ((i == numArgs) && ((localPtr->name[0] == 'a')
	        && (strcmp(localPtr->name, "args") == 0))) {
	    Tcl_Obj *listPtr = Tcl_NewListObj(argCt, &(objv[i]));
	    varPtr->value.objPtr = listPtr;
	    Tcl_IncrRefCount(listPtr); /* local var is a reference */
	    varPtr->flags &= ~VAR_UNDEFINED;
	    argCt = 0;
	    break;		/* done processing args */
	} else if (argCt > 0) {
	    Tcl_Obj *objPtr = objv[i];
	    varPtr->value.objPtr = objPtr;
	    varPtr->flags &= ~VAR_UNDEFINED;
	    Tcl_IncrRefCount(objPtr);  /* since the local variable now has
					* another reference to object. */
	} else if (localPtr->defValuePtr != NULL) {
	    Tcl_Obj *objPtr = localPtr->defValuePtr;
	    varPtr->value.objPtr = objPtr;
	    varPtr->flags &= ~VAR_UNDEFINED;
	    Tcl_IncrRefCount(objPtr);  /* since the local variable now has
					* another reference to object. */
	} else {
	    Tcl_ResetResult(interp);
	    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		    "no value given for parameter \"", localPtr->name,
		    "\" to \"", Tcl_GetStringFromObj(objv[0], (int *) NULL),
		    "\"", (char *) NULL);
	    result = TCL_ERROR;
	    goto procDone;
	}
	varPtr++;
	localPtr = localPtr->nextPtr;
    }
    if (argCt > 0) {
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"called \"", Tcl_GetStringFromObj(objv[0], (int *) NULL),
		"\" with too many arguments", (char *) NULL);
	result = TCL_ERROR;
	goto procDone;
    }

    /*
     * Invoke the commands in the procedure's body.
     */

    if (tclTraceExec >= 1) {
	fprintf(stdout, "Calling proc ");
	for (i = 0;  i < objc;  i++) {
	    bytes = Tcl_GetStringFromObj(objv[i], &length);
	    TclPrintSource(stdout, bytes, TclMin(length, 15));
	    fprintf(stdout, " ");
	}
	fprintf(stdout, "\n");
	fflush(stdout);
    }

    iPtr->returnCode = TCL_OK;
    procPtr->refCount++;
    result = Tcl_EvalObj(interp, procPtr->bodyPtr);
    procPtr->refCount--;
    if (procPtr->refCount <= 0) {
	TclProcCleanupProc(procPtr);
    }

    if (result != TCL_OK) {
	if (result == TCL_RETURN) {
	    result = TclUpdateReturnInfo(iPtr);
	} else if (result == TCL_ERROR) {
	    char msg[100];
	    sprintf(msg, "\n    (procedure \"%.50s\" line %d)",
		    procName, iPtr->errorLine);
	    Tcl_AddObjErrorInfo(interp, msg, -1);
	} else if (result == TCL_BREAK) {
	    Tcl_ResetResult(interp);
	    Tcl_AppendToObj(Tcl_GetObjResult(interp),
	            "invoked \"break\" outside of a loop", -1);
	    result = TCL_ERROR;
	} else if (result == TCL_CONTINUE) {
	    Tcl_ResetResult(interp);
	    Tcl_AppendToObj(Tcl_GetObjResult(interp),
		    "invoked \"continue\" outside of a loop", -1);
	    result = TCL_ERROR;
	}
    }
    
    procDone:

    /*
     * Pop and free the call frame for this procedure invocation.
     */
    
    Tcl_PopCallFrame(interp);
    
    /*
     * Free the compiledLocals array if malloc'ed storage was used.
     */

    if (compiledLocals != localStorage) {
	ckfree((char *) compiledLocals);
    }
    return result;
#undef NUM_LOCALS
}

/*
 *----------------------------------------------------------------------
 *
 * TclProcCompileProc --
 *
 *	Called just before a procedure is executed to compile the
 *	body to byte codes.  If the type of the body is not
 *	"byte code" or if the compile conditions have changed
 *	(namespace context, epoch counters, etc.) then the body
 *	is recompiled.  Otherwise, this procedure does nothing.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	May change the internal representation of the body object
 *	to compiled code.
 *
 *----------------------------------------------------------------------
 */
 
int
TclProcCompileProc(interp, procPtr, bodyPtr, nsPtr, description, procName)
    Tcl_Interp *interp;		/* Interpreter containing procedure. */
    Proc *procPtr;		/* Data associated with procedure. */
    Tcl_Obj *bodyPtr;		/* Body of proc. (Usually procPtr->bodyPtr,
 				 * but could be any code fragment compiled
 				 * in the context of this procedure.) */
    Namespace *nsPtr;		/* Namespace containing procedure. */
    CONST char *description;	/* string describing this body of code. */
    CONST char *procName;	/* Name of this procedure. */
{
    Interp *iPtr = (Interp*)interp;
    int result;
    Tcl_CallFrame frame;
    Proc *saveProcPtr;
 
    /*
     * If necessary, compile the procedure's body. The compiler will
     * allocate frame slots for the procedure's non-argument local
     * variables. If the ByteCode already exists, make sure it hasn't been
     * invalidated by someone redefining a core command (this might make the
     * compiled code wrong). Also, if the code was compiled in/for a
     * different interpreter, we recompile it. Note that compiling the body
     * might increase procPtr->numCompiledLocals if new local variables are
     * found while compiling.
     *
     * Precompiled procedure bodies, however, are immutable and therefore
     * they are not recompiled, even if things have changed.
     */
 
    if (bodyPtr->typePtr == &tclByteCodeType) {
 	ByteCode *codePtr = (ByteCode *) bodyPtr->internalRep.otherValuePtr;
 
 	if ((codePtr->iPtr != iPtr)
 	        || (codePtr->compileEpoch != iPtr->compileEpoch)
 	        || (codePtr->nsPtr != nsPtr)
 	        || (codePtr->nsEpoch != nsPtr->resolverEpoch)) {
            if (codePtr->flags & TCL_BYTECODE_PRECOMPILED) {
                if (codePtr->iPtr != iPtr) {
                    Tcl_AppendResult(interp,
                            "a precompiled script jumped interps", NULL);
                    return TCL_ERROR;
                }
	        codePtr->compileEpoch = iPtr->compileEpoch;
 	        codePtr->nsEpoch = nsPtr->resolverEpoch;
                codePtr->nsPtr = nsPtr;
            } else {
                tclByteCodeType.freeIntRepProc(bodyPtr);
                bodyPtr->typePtr = (Tcl_ObjType *) NULL;
            }
 	}
    }
    if (bodyPtr->typePtr != &tclByteCodeType) {
 	char buf[100];
 	int numChars;
 	char *ellipsis;
 	
 	if (tclTraceCompile >= 1) {
 	    /*
 	     * Display a line summarizing the top level command we
 	     * are about to compile.
 	     */
 
 	    numChars = strlen(procName);
 	    ellipsis = "";
 	    if (numChars > 50) {
 		numChars = 50;
 		ellipsis = "...";
 	    }
 	    fprintf(stdout, "Compiling %s \"%.*s%s\"\n",
 		    description, numChars, procName, ellipsis);
 	}
 	
 	/*
 	 * Plug the current procPtr into the interpreter and coerce
 	 * the code body to byte codes.  The interpreter needs to
 	 * know which proc it's compiling so that it can access its
 	 * list of compiled locals.
 	 *
 	 * TRICKY NOTE:  Be careful to push a call frame with the
 	 *   proper namespace context, so that the byte codes are
 	 *   compiled in the appropriate class context.
 	 */
 
 	saveProcPtr = iPtr->compiledProcPtr;
 	iPtr->compiledProcPtr = procPtr;
 
 	result = Tcl_PushCallFrame(interp, &frame,
		(Tcl_Namespace*)nsPtr, /* isProcCallFrame */ 0);
 
 	if (result == TCL_OK) {
	    result = tclByteCodeType.setFromAnyProc(interp, bodyPtr);
	    Tcl_PopCallFrame(interp);
	}
 
 	iPtr->compiledProcPtr = saveProcPtr;
 	
 	if (result != TCL_OK) {
 	    if (result == TCL_ERROR) {
 		numChars = strlen(procName);
 		ellipsis = "";
 		if (numChars > 50) {
 		    numChars = 50;
 		    ellipsis = "...";
 		}
 		sprintf(buf, "\n    (compiling %s \"%.*s%s\", line %d)",
 			description, numChars, procName, ellipsis,
 			interp->errorLine);
 		Tcl_AddObjErrorInfo(interp, buf, -1);
 	    }
 	    return result;
 	}
    }
    return TCL_OK;
}
 

/*
 *----------------------------------------------------------------------
 *
 * TclProcDeleteProc --
 *
 *	This procedure is invoked just before a command procedure is
 *	removed from an interpreter.  Its job is to release all the
 *	resources allocated to the procedure.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory gets freed, unless the procedure is actively being
 *	executed.  In this case the cleanup is delayed until the
 *	last call to the current procedure completes.
 *
 *----------------------------------------------------------------------
 */

void
TclProcDeleteProc(clientData)
    ClientData clientData;		/* Procedure to be deleted. */
{
    Proc *procPtr = (Proc *) clientData;

    procPtr->refCount--;
    if (procPtr->refCount <= 0) {
	TclProcCleanupProc(procPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclProcCleanupProc --
 *
 *	This procedure does all the real work of freeing up a Proc
 *	structure.  It's called only when the structure's reference
 *	count becomes zero.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory gets freed.
 *
 *----------------------------------------------------------------------
 */

void
TclProcCleanupProc(procPtr)
    register Proc *procPtr;		/* Procedure to be deleted. */
{
    register CompiledLocal *localPtr;
    Tcl_Obj *bodyPtr = procPtr->bodyPtr;
    Tcl_Obj *defPtr;
    Tcl_ResolvedVarInfo *resVarInfo;

    if (bodyPtr != NULL) {
	Tcl_DecrRefCount(bodyPtr);
    }
    for (localPtr = procPtr->firstLocalPtr;  localPtr != NULL;  ) {
	CompiledLocal *nextPtr = localPtr->nextPtr;

        resVarInfo = localPtr->resolveInfo;
	if (resVarInfo && resVarInfo->deleteProc) {
            (*resVarInfo->deleteProc)(resVarInfo->identity);
            resVarInfo->identity = NULL;
	    ckfree((char *) resVarInfo);
        }

	if (localPtr->defValuePtr != NULL) {
	    defPtr = localPtr->defValuePtr;
	    Tcl_DecrRefCount(defPtr);
	}
	ckfree((char *) localPtr);
	localPtr = nextPtr;
    }
    ckfree((char *) procPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * TclUpdateReturnInfo --
 *
 *	This procedure is called when procedures return, and at other
 *	points where the TCL_RETURN code is used.  It examines fields
 *	such as iPtr->returnCode and iPtr->errorCode and modifies
 *	the real return status accordingly.
 *
 * Results:
 *	The return value is the true completion code to use for
 *	the procedure, instead of TCL_RETURN.
 *
 * Side effects:
 *	The errorInfo and errorCode variables may get modified.
 *
 *----------------------------------------------------------------------
 */

int
TclUpdateReturnInfo(iPtr)
    Interp *iPtr;		/* Interpreter for which TCL_RETURN
				 * exception is being processed. */
{
    int code;

    code = iPtr->returnCode;
    iPtr->returnCode = TCL_OK;
    if (code == TCL_ERROR) {
	Tcl_SetVar2((Tcl_Interp *) iPtr, "errorCode", (char *) NULL,
		(iPtr->errorCode != NULL) ? iPtr->errorCode : "NONE",
		TCL_GLOBAL_ONLY);
	iPtr->flags |= ERROR_CODE_SET;
	if (iPtr->errorInfo != NULL) {
	    Tcl_SetVar2((Tcl_Interp *) iPtr, "errorInfo", (char *) NULL,
		    iPtr->errorInfo, TCL_GLOBAL_ONLY);
	    iPtr->flags |= ERR_IN_PROGRESS;
	}
    }
    return code;
}

/*
 *----------------------------------------------------------------------
 *
 * TclGetInterpProc --
 *
 *  Returns a pointer to the TclProcInterpProc procedure; this is different
 *  from the value obtained from the TclProcInterpProc reference on systems
 *  like Windows where import and export versions of a procedure exported
 *  by a DLL exist.
 *
 * Results:
 *  Returns the internal address of the TclProcInterpProc procedure.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

TclCmdProcType
TclGetInterpProc()
{
    return TclProcInterpProc;
}

/*
 *----------------------------------------------------------------------
 *
 * TclGetObjInterpProc --
 *
 *  Returns a pointer to the TclObjInterpProc procedure; this is different
 *  from the value obtained from the TclObjInterpProc reference on systems
 *  like Windows where import and export versions of a procedure exported
 *  by a DLL exist.
 *
 * Results:
 *  Returns the internal address of the TclProcInterpProc procedure.
 *
 * Side effects:
 *  None.
 *
 *----------------------------------------------------------------------
 */

TclObjCmdProcType
TclGetObjInterpProc()
{
    return TclObjInterpProc;
}