xref: /netbsd/usr.bin/make/var.c (revision bf9ec67e)
1 /*	$NetBSD: var.c,v 1.69 2002/03/21 01:24:44 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1989 by Berkeley Softworks
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Adam de Boor.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #ifdef MAKE_BOOTSTRAP
42 static char rcsid[] = "$NetBSD: var.c,v 1.69 2002/03/21 01:24:44 christos Exp $";
43 #else
44 #include <sys/cdefs.h>
45 #ifndef lint
46 #if 0
47 static char sccsid[] = "@(#)var.c	8.3 (Berkeley) 3/19/94";
48 #else
49 __RCSID("$NetBSD: var.c,v 1.69 2002/03/21 01:24:44 christos Exp $");
50 #endif
51 #endif /* not lint */
52 #endif
53 
54 /*-
55  * var.c --
56  *	Variable-handling functions
57  *
58  * Interface:
59  *	Var_Set	  	    Set the value of a variable in the given
60  *	    	  	    context. The variable is created if it doesn't
61  *	    	  	    yet exist. The value and variable name need not
62  *	    	  	    be preserved.
63  *
64  *	Var_Append	    Append more characters to an existing variable
65  *	    	  	    in the given context. The variable needn't
66  *	    	  	    exist already -- it will be created if it doesn't.
67  *	    	  	    A space is placed between the old value and the
68  *	    	  	    new one.
69  *
70  *	Var_Exists	    See if a variable exists.
71  *
72  *	Var_Value 	    Return the value of a variable in a context or
73  *	    	  	    NULL if the variable is undefined.
74  *
75  *	Var_Subst 	    Substitute named variable, or all variables if
76  *			    NULL in a string using
77  *	    	  	    the given context as the top-most one. If the
78  *	    	  	    third argument is non-zero, Parse_Error is
79  *	    	  	    called if any variables are undefined.
80  *
81  *	Var_Parse 	    Parse a variable expansion from a string and
82  *	    	  	    return the result and the number of characters
83  *	    	  	    consumed.
84  *
85  *	Var_Delete	    Delete a variable in a context.
86  *
87  *	Var_Init  	    Initialize this module.
88  *
89  * Debugging:
90  *	Var_Dump  	    Print out all variables defined in the given
91  *	    	  	    context.
92  *
93  * XXX: There's a lot of duplication in these functions.
94  */
95 
96 #include    <ctype.h>
97 #ifndef NO_REGEX
98 #include    <sys/types.h>
99 #include    <regex.h>
100 #endif
101 #include    <stdlib.h>
102 #include    "make.h"
103 #include    "buf.h"
104 
105 /*
106  * This is a harmless return value for Var_Parse that can be used by Var_Subst
107  * to determine if there was an error in parsing -- easier than returning
108  * a flag, as things outside this module don't give a hoot.
109  */
110 char 	var_Error[] = "";
111 
112 /*
113  * Similar to var_Error, but returned when the 'err' flag for Var_Parse is
114  * set false. Why not just use a constant? Well, gcc likes to condense
115  * identical string instances...
116  */
117 static char	varNoError[] = "";
118 
119 /*
120  * Internally, variables are contained in four different contexts.
121  *	1) the environment. They may not be changed. If an environment
122  *	    variable is appended-to, the result is placed in the global
123  *	    context.
124  *	2) the global context. Variables set in the Makefile are located in
125  *	    the global context. It is the penultimate context searched when
126  *	    substituting.
127  *	3) the command-line context. All variables set on the command line
128  *	   are placed in this context. They are UNALTERABLE once placed here.
129  *	4) the local context. Each target has associated with it a context
130  *	   list. On this list are located the structures describing such
131  *	   local variables as $(@) and $(*)
132  * The four contexts are searched in the reverse order from which they are
133  * listed.
134  */
135 GNode          *VAR_GLOBAL;   /* variables from the makefile */
136 GNode          *VAR_CMD;      /* variables defined on the command-line */
137 
138 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
139 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
140 #define FIND_ENV  	0x4   /* look in the environment also */
141 
142 typedef struct Var {
143     char          *name;	/* the variable's name */
144     Buffer	  val;	    	/* its value */
145     int	    	  flags;    	/* miscellaneous status flags */
146 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
147 				     * Used to avoid recursion */
148 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
149 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
150 				     * should be destroyed when done with
151 				     * it. Used by Var_Parse for undefined,
152 				     * modified variables */
153 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
154 				     * a use for it in some modifier and
155 				     * the value is therefore valid */
156 }  Var;
157 
158 
159 /* Var*Pattern flags */
160 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
161 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
162 #define VAR_SUB_MATCHED	0x04	/* There was a match */
163 #define VAR_MATCH_START	0x08	/* Match at start of word */
164 #define VAR_MATCH_END	0x10	/* Match at end of word */
165 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
166 
167 /* Var_Set flags */
168 #define VAR_NO_EXPORT	0x01	/* do not export */
169 
170 typedef struct {
171     char    	  *lhs;	    /* String to match */
172     int	    	   leftLen; /* Length of string */
173     char    	  *rhs;	    /* Replacement string (w/ &'s removed) */
174     int	    	  rightLen; /* Length of replacement */
175     int	    	  flags;
176 } VarPattern;
177 
178 typedef struct {
179     GNode	*ctxt;		/* variable context */
180     char	*tvar;		/* name of temp var */
181     int		tvarLen;
182     char	*str;		/* string to expand */
183     int		strLen;
184     int		err;		/* err for not defined */
185 } VarLoop_t;
186 
187 #ifndef NO_REGEX
188 typedef struct {
189     regex_t	   re;
190     int		   nsub;
191     regmatch_t 	  *matches;
192     char 	  *replace;
193     int		   flags;
194 } VarREPattern;
195 #endif
196 
197 static Var *VarFind __P((char *, GNode *, int));
198 static void VarAdd __P((char *, char *, GNode *));
199 static Boolean VarHead __P((GNode *, char *, Boolean, Buffer, ClientData));
200 static Boolean VarTail __P((GNode *, char *, Boolean, Buffer, ClientData));
201 static Boolean VarSuffix __P((GNode *, char *, Boolean, Buffer, ClientData));
202 static Boolean VarRoot __P((GNode *, char *, Boolean, Buffer, ClientData));
203 static Boolean VarMatch __P((GNode *, char *, Boolean, Buffer, ClientData));
204 #ifdef SYSVVARSUB
205 static Boolean VarSYSVMatch __P((GNode *, char *, Boolean, Buffer,
206 				 ClientData));
207 #endif
208 static Boolean VarNoMatch __P((GNode *, char *, Boolean, Buffer, ClientData));
209 #ifndef NO_REGEX
210 static void VarREError __P((int, regex_t *, const char *));
211 static Boolean VarRESubstitute __P((GNode *, char *, Boolean, Buffer,
212 				    ClientData));
213 #endif
214 static Boolean VarSubstitute __P((GNode *, char *, Boolean, Buffer,
215 				  ClientData));
216 static Boolean VarLoopExpand __P((GNode *, char *, Boolean, Buffer,
217 				  ClientData));
218 static char *VarGetPattern __P((GNode *, int, char **, int, int *, int *,
219 				VarPattern *));
220 static char *VarQuote __P((char *));
221 static char *VarChangeCase __P((char *, int));
222 static char *VarModify __P((GNode *, char *, Boolean (*)(GNode *, char *,
223 							 Boolean, Buffer,
224 							 ClientData),
225 			    ClientData));
226 static char *VarSort __P((char *));
227 static char *VarUniq __P((char *));
228 static int VarWordCompare __P((const void *, const void *));
229 static void VarPrintVar __P((ClientData));
230 
231 /*-
232  *-----------------------------------------------------------------------
233  * VarFind --
234  *	Find the given variable in the given context and any other contexts
235  *	indicated.
236  *
237  * Results:
238  *	A pointer to the structure describing the desired variable or
239  *	NIL if the variable does not exist.
240  *
241  * Side Effects:
242  *	None
243  *-----------------------------------------------------------------------
244  */
245 static Var *
246 VarFind (name, ctxt, flags)
247     char           	*name;	/* name to find */
248     GNode          	*ctxt;	/* context in which to find it */
249     int             	flags;	/* FIND_GLOBAL set means to look in the
250 				 * VAR_GLOBAL context as well.
251 				 * FIND_CMD set means to look in the VAR_CMD
252 				 * context also.
253 				 * FIND_ENV set means to look in the
254 				 * environment */
255 {
256     Hash_Entry         	*var;
257     Var		  	*v;
258 
259 	/*
260 	 * If the variable name begins with a '.', it could very well be one of
261 	 * the local ones.  We check the name against all the local variables
262 	 * and substitute the short version in for 'name' if it matches one of
263 	 * them.
264 	 */
265 	if (*name == '.' && isupper((unsigned char) name[1]))
266 		switch (name[1]) {
267 		case 'A':
268 			if (!strcmp(name, ".ALLSRC"))
269 				name = ALLSRC;
270 			if (!strcmp(name, ".ARCHIVE"))
271 				name = ARCHIVE;
272 			break;
273 		case 'I':
274 			if (!strcmp(name, ".IMPSRC"))
275 				name = IMPSRC;
276 			break;
277 		case 'M':
278 			if (!strcmp(name, ".MEMBER"))
279 				name = MEMBER;
280 			break;
281 		case 'O':
282 			if (!strcmp(name, ".OODATE"))
283 				name = OODATE;
284 			break;
285 		case 'P':
286 			if (!strcmp(name, ".PREFIX"))
287 				name = PREFIX;
288 			break;
289 		case 'T':
290 			if (!strcmp(name, ".TARGET"))
291 				name = TARGET;
292 			break;
293 		}
294     /*
295      * First look for the variable in the given context. If it's not there,
296      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
297      * depending on the FIND_* flags in 'flags'
298      */
299     var = Hash_FindEntry (&ctxt->context, name);
300 
301     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
302 	var = Hash_FindEntry (&VAR_CMD->context, name);
303     }
304     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
305 	(ctxt != VAR_GLOBAL))
306     {
307 	var = Hash_FindEntry (&VAR_GLOBAL->context, name);
308     }
309     if ((var == NULL) && (flags & FIND_ENV)) {
310 	char *env;
311 
312 	if ((env = getenv (name)) != NULL) {
313 	    int	  	len;
314 
315 	    v = (Var *) emalloc(sizeof(Var));
316 	    v->name = estrdup(name);
317 
318 	    len = strlen(env);
319 
320 	    v->val = Buf_Init(len);
321 	    Buf_AddBytes(v->val, len, (Byte *)env);
322 
323 	    v->flags = VAR_FROM_ENV;
324 	    return (v);
325 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
326 		   (ctxt != VAR_GLOBAL))
327 	{
328 	    var = Hash_FindEntry (&VAR_GLOBAL->context, name);
329 	    if (var == NULL) {
330 		return ((Var *) NIL);
331 	    } else {
332 		return ((Var *)Hash_GetValue(var));
333 	    }
334 	} else {
335 	    return((Var *)NIL);
336 	}
337     } else if (var == NULL) {
338 	return ((Var *) NIL);
339     } else {
340 	return ((Var *) Hash_GetValue(var));
341     }
342 }
343 
344 /*-
345  *-----------------------------------------------------------------------
346  * VarAdd  --
347  *	Add a new variable of name name and value val to the given context
348  *
349  * Results:
350  *	None
351  *
352  * Side Effects:
353  *	The new variable is placed at the front of the given context
354  *	The name and val arguments are duplicated so they may
355  *	safely be freed.
356  *-----------------------------------------------------------------------
357  */
358 static void
359 VarAdd (name, val, ctxt)
360     char           *name;	/* name of variable to add */
361     char           *val;	/* value to set it to */
362     GNode          *ctxt;	/* context in which to set it */
363 {
364     register Var   *v;
365     int	    	  len;
366     Hash_Entry      *h;
367 
368     v = (Var *) emalloc (sizeof (Var));
369 
370     len = val ? strlen(val) : 0;
371     v->val = Buf_Init(len+1);
372     Buf_AddBytes(v->val, len, (Byte *)val);
373 
374     v->flags = 0;
375 
376     h = Hash_CreateEntry (&ctxt->context, name, NULL);
377     Hash_SetValue(h, v);
378     v->name = h->name;
379     if (DEBUG(VAR)) {
380 	printf("%s:%s = %s\n", ctxt->name, name, val);
381     }
382 }
383 
384 /*-
385  *-----------------------------------------------------------------------
386  * Var_Delete --
387  *	Remove a variable from a context.
388  *
389  * Results:
390  *	None.
391  *
392  * Side Effects:
393  *	The Var structure is removed and freed.
394  *
395  *-----------------------------------------------------------------------
396  */
397 void
398 Var_Delete(name, ctxt)
399     char    	  *name;
400     GNode	  *ctxt;
401 {
402     Hash_Entry 	  *ln;
403 
404     if (DEBUG(VAR)) {
405 	printf("%s:delete %s\n", ctxt->name, name);
406     }
407     ln = Hash_FindEntry(&ctxt->context, name);
408     if (ln != NULL) {
409 	register Var 	  *v;
410 
411 	v = (Var *)Hash_GetValue(ln);
412 	if (v->name != ln->name)
413 		free(v->name);
414 	Hash_DeleteEntry(&ctxt->context, ln);
415 	Buf_Destroy(v->val, TRUE);
416 	free((Address) v);
417     }
418 }
419 
420 /*-
421  *-----------------------------------------------------------------------
422  * Var_Set --
423  *	Set the variable name to the value val in the given context.
424  *
425  * Results:
426  *	None.
427  *
428  * Side Effects:
429  *	If the variable doesn't yet exist, a new record is created for it.
430  *	Else the old value is freed and the new one stuck in its place
431  *
432  * Notes:
433  *	The variable is searched for only in its context before being
434  *	created in that context. I.e. if the context is VAR_GLOBAL,
435  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
436  *	VAR_CMD->context is searched. This is done to avoid the literally
437  *	thousands of unnecessary strcmp's that used to be done to
438  *	set, say, $(@) or $(<).
439  *-----------------------------------------------------------------------
440  */
441 void
442 Var_Set (name, val, ctxt, flags)
443     char           *name;	/* name of variable to set */
444     char           *val;	/* value to give to the variable */
445     GNode          *ctxt;	/* context in which to set it */
446     int		   flags;
447 {
448     register Var   *v;
449     char *cp = name;
450 
451     /*
452      * We only look for a variable in the given context since anything set
453      * here will override anything in a lower context, so there's not much
454      * point in searching them all just to save a bit of memory...
455      */
456     if ((name = strchr(cp, '$'))) {
457 	name = Var_Subst(NULL, cp, ctxt, 0);
458     } else
459 	name = cp;
460     v = VarFind (name, ctxt, 0);
461     if (v == (Var *) NIL) {
462 	VarAdd (name, val, ctxt);
463     } else {
464 	Buf_Discard(v->val, Buf_Size(v->val));
465 	Buf_AddBytes(v->val, strlen(val), (Byte *)val);
466 
467 	if (DEBUG(VAR)) {
468 	    printf("%s:%s = %s\n", ctxt->name, name, val);
469 	}
470     }
471     /*
472      * Any variables given on the command line are automatically exported
473      * to the environment (as per POSIX standard)
474      */
475     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
476 
477 	setenv(name, val, 1);
478 
479 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
480     }
481     if (name != cp)
482 	free(name);
483 }
484 
485 /*-
486  *-----------------------------------------------------------------------
487  * Var_Append --
488  *	The variable of the given name has the given value appended to it in
489  *	the given context.
490  *
491  * Results:
492  *	None
493  *
494  * Side Effects:
495  *	If the variable doesn't exist, it is created. Else the strings
496  *	are concatenated (with a space in between).
497  *
498  * Notes:
499  *	Only if the variable is being sought in the global context is the
500  *	environment searched.
501  *	XXX: Knows its calling circumstances in that if called with ctxt
502  *	an actual target, it will only search that context since only
503  *	a local variable could be being appended to. This is actually
504  *	a big win and must be tolerated.
505  *-----------------------------------------------------------------------
506  */
507 void
508 Var_Append (name, val, ctxt)
509     char           *name;	/* Name of variable to modify */
510     char           *val;	/* String to append to it */
511     GNode          *ctxt;	/* Context in which this should occur */
512 {
513     register Var   *v;
514     Hash_Entry	   *h;
515     char *cp = name;
516 
517     if ((name = strchr(cp, '$'))) {
518 	name = Var_Subst(NULL, cp, ctxt, 0);
519     } else
520 	name = cp;
521 
522     v = VarFind (name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
523 
524     if (v == (Var *) NIL) {
525 	VarAdd (name, val, ctxt);
526     } else {
527 	Buf_AddByte(v->val, (Byte)' ');
528 	Buf_AddBytes(v->val, strlen(val), (Byte *)val);
529 
530 	if (DEBUG(VAR)) {
531 	    printf("%s:%s = %s\n", ctxt->name, name,
532 		   (char *) Buf_GetAll(v->val, (int *)NULL));
533 	}
534 
535 	if (v->flags & VAR_FROM_ENV) {
536 	    /*
537 	     * If the original variable came from the environment, we
538 	     * have to install it in the global context (we could place
539 	     * it in the environment, but then we should provide a way to
540 	     * export other variables...)
541 	     */
542 	    v->flags &= ~VAR_FROM_ENV;
543 	    h = Hash_CreateEntry (&ctxt->context, name, NULL);
544 	    Hash_SetValue(h, v);
545 	}
546     }
547     if (name != cp)
548 	free(name);
549 }
550 
551 /*-
552  *-----------------------------------------------------------------------
553  * Var_Exists --
554  *	See if the given variable exists.
555  *
556  * Results:
557  *	TRUE if it does, FALSE if it doesn't
558  *
559  * Side Effects:
560  *	None.
561  *
562  *-----------------------------------------------------------------------
563  */
564 Boolean
565 Var_Exists(name, ctxt)
566     char	  *name;    	/* Variable to find */
567     GNode	  *ctxt;    	/* Context in which to start search */
568 {
569     Var	    	  *v;
570 
571     v = VarFind(name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
572 
573     if (v == (Var *)NIL) {
574 	return(FALSE);
575     } else if (v->flags & VAR_FROM_ENV) {
576 	free(v->name);
577 	Buf_Destroy(v->val, TRUE);
578 	free((char *)v);
579     }
580     return(TRUE);
581 }
582 
583 /*-
584  *-----------------------------------------------------------------------
585  * Var_Value --
586  *	Return the value of the named variable in the given context
587  *
588  * Results:
589  *	The value if the variable exists, NULL if it doesn't
590  *
591  * Side Effects:
592  *	None
593  *-----------------------------------------------------------------------
594  */
595 char *
596 Var_Value (name, ctxt, frp)
597     char           *name;	/* name to find */
598     GNode          *ctxt;	/* context in which to search for it */
599     char	   **frp;
600 {
601     Var            *v;
602 
603     v = VarFind (name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
604     *frp = NULL;
605     if (v != (Var *) NIL) {
606 	char *p = ((char *)Buf_GetAll(v->val, (int *)NULL));
607 	if (v->flags & VAR_FROM_ENV) {
608 	    free(v->name);
609 	    Buf_Destroy(v->val, FALSE);
610 	    free((Address) v);
611 	    *frp = p;
612 	}
613 	return p;
614     } else {
615 	return ((char *) NULL);
616     }
617 }
618 
619 /*-
620  *-----------------------------------------------------------------------
621  * VarHead --
622  *	Remove the tail of the given word and place the result in the given
623  *	buffer.
624  *
625  * Results:
626  *	TRUE if characters were added to the buffer (a space needs to be
627  *	added to the buffer before the next word).
628  *
629  * Side Effects:
630  *	The trimmed word is added to the buffer.
631  *
632  *-----------------------------------------------------------------------
633  */
634 static Boolean
635 VarHead (ctx, word, addSpace, buf, dummy)
636     GNode	  *ctx;
637     char    	  *word;    	/* Word to trim */
638     Boolean 	  addSpace; 	/* True if need to add a space to the buffer
639 				 * before sticking in the head */
640     Buffer  	  buf;	    	/* Buffer in which to store it */
641     ClientData	  dummy;
642 {
643     register char *slash;
644 
645     slash = strrchr (word, '/');
646     if (slash != (char *)NULL) {
647 	if (addSpace) {
648 	    Buf_AddByte (buf, (Byte)' ');
649 	}
650 	*slash = '\0';
651 	Buf_AddBytes (buf, strlen (word), (Byte *)word);
652 	*slash = '/';
653 	return (TRUE);
654     } else {
655 	/*
656 	 * If no directory part, give . (q.v. the POSIX standard)
657 	 */
658 	if (addSpace) {
659 	    Buf_AddBytes(buf, 2, (Byte *)" .");
660 	} else {
661 	    Buf_AddByte(buf, (Byte)'.');
662 	}
663     }
664     return(dummy ? TRUE : TRUE);
665 }
666 
667 /*-
668  *-----------------------------------------------------------------------
669  * VarTail --
670  *	Remove the head of the given word and place the result in the given
671  *	buffer.
672  *
673  * Results:
674  *	TRUE if characters were added to the buffer (a space needs to be
675  *	added to the buffer before the next word).
676  *
677  * Side Effects:
678  *	The trimmed word is added to the buffer.
679  *
680  *-----------------------------------------------------------------------
681  */
682 static Boolean
683 VarTail (ctx, word, addSpace, buf, dummy)
684     GNode	  *ctx;
685     char    	  *word;    	/* Word to trim */
686     Boolean 	  addSpace; 	/* TRUE if need to stick a space in the
687 				 * buffer before adding the tail */
688     Buffer  	  buf;	    	/* Buffer in which to store it */
689     ClientData	  dummy;
690 {
691     register char *slash;
692 
693     if (addSpace) {
694 	Buf_AddByte (buf, (Byte)' ');
695     }
696 
697     slash = strrchr (word, '/');
698     if (slash != (char *)NULL) {
699 	*slash++ = '\0';
700 	Buf_AddBytes (buf, strlen(slash), (Byte *)slash);
701 	slash[-1] = '/';
702     } else {
703 	Buf_AddBytes (buf, strlen(word), (Byte *)word);
704     }
705     return (dummy ? TRUE : TRUE);
706 }
707 
708 /*-
709  *-----------------------------------------------------------------------
710  * VarSuffix --
711  *	Place the suffix of the given word in the given buffer.
712  *
713  * Results:
714  *	TRUE if characters were added to the buffer (a space needs to be
715  *	added to the buffer before the next word).
716  *
717  * Side Effects:
718  *	The suffix from the word is placed in the buffer.
719  *
720  *-----------------------------------------------------------------------
721  */
722 static Boolean
723 VarSuffix (ctx, word, addSpace, buf, dummy)
724     GNode	  *ctx;
725     char    	  *word;    	/* Word to trim */
726     Boolean 	  addSpace; 	/* TRUE if need to add a space before placing
727 				 * the suffix in the buffer */
728     Buffer  	  buf;	    	/* Buffer in which to store it */
729     ClientData	  dummy;
730 {
731     register char *dot;
732 
733     dot = strrchr (word, '.');
734     if (dot != (char *)NULL) {
735 	if (addSpace) {
736 	    Buf_AddByte (buf, (Byte)' ');
737 	}
738 	*dot++ = '\0';
739 	Buf_AddBytes (buf, strlen (dot), (Byte *)dot);
740 	dot[-1] = '.';
741 	addSpace = TRUE;
742     }
743     return (dummy ? addSpace : addSpace);
744 }
745 
746 /*-
747  *-----------------------------------------------------------------------
748  * VarRoot --
749  *	Remove the suffix of the given word and place the result in the
750  *	buffer.
751  *
752  * Results:
753  *	TRUE if characters were added to the buffer (a space needs to be
754  *	added to the buffer before the next word).
755  *
756  * Side Effects:
757  *	The trimmed word is added to the buffer.
758  *
759  *-----------------------------------------------------------------------
760  */
761 static Boolean
762 VarRoot (ctx, word, addSpace, buf, dummy)
763     GNode	  *ctx;
764     char    	  *word;    	/* Word to trim */
765     Boolean 	  addSpace; 	/* TRUE if need to add a space to the buffer
766 				 * before placing the root in it */
767     Buffer  	  buf;	    	/* Buffer in which to store it */
768     ClientData	  dummy;
769 {
770     register char *dot;
771 
772     if (addSpace) {
773 	Buf_AddByte (buf, (Byte)' ');
774     }
775 
776     dot = strrchr (word, '.');
777     if (dot != (char *)NULL) {
778 	*dot = '\0';
779 	Buf_AddBytes (buf, strlen (word), (Byte *)word);
780 	*dot = '.';
781     } else {
782 	Buf_AddBytes (buf, strlen(word), (Byte *)word);
783     }
784     return (dummy ? TRUE : TRUE);
785 }
786 
787 /*-
788  *-----------------------------------------------------------------------
789  * VarMatch --
790  *	Place the word in the buffer if it matches the given pattern.
791  *	Callback function for VarModify to implement the :M modifier.
792  *
793  * Results:
794  *	TRUE if a space should be placed in the buffer before the next
795  *	word.
796  *
797  * Side Effects:
798  *	The word may be copied to the buffer.
799  *
800  *-----------------------------------------------------------------------
801  */
802 static Boolean
803 VarMatch (ctx, word, addSpace, buf, pattern)
804     GNode	  *ctx;
805     char    	  *word;    	/* Word to examine */
806     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
807 				 * buffer before adding the word, if it
808 				 * matches */
809     Buffer  	  buf;	    	/* Buffer in which to store it */
810     ClientData    pattern; 	/* Pattern the word must match */
811 {
812     if (Str_Match(word, (char *) pattern)) {
813 	if (addSpace) {
814 	    Buf_AddByte(buf, (Byte)' ');
815 	}
816 	addSpace = TRUE;
817 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
818     }
819     return(addSpace);
820 }
821 
822 #ifdef SYSVVARSUB
823 /*-
824  *-----------------------------------------------------------------------
825  * VarSYSVMatch --
826  *	Place the word in the buffer if it matches the given pattern.
827  *	Callback function for VarModify to implement the System V %
828  *	modifiers.
829  *
830  * Results:
831  *	TRUE if a space should be placed in the buffer before the next
832  *	word.
833  *
834  * Side Effects:
835  *	The word may be copied to the buffer.
836  *
837  *-----------------------------------------------------------------------
838  */
839 static Boolean
840 VarSYSVMatch (ctx, word, addSpace, buf, patp)
841     GNode	  *ctx;
842     char    	  *word;    	/* Word to examine */
843     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
844 				 * buffer before adding the word, if it
845 				 * matches */
846     Buffer  	  buf;	    	/* Buffer in which to store it */
847     ClientData 	  patp; 	/* Pattern the word must match */
848 {
849     int len;
850     char *ptr;
851     VarPattern 	  *pat = (VarPattern *) patp;
852     char *varexp;
853 
854     if (addSpace)
855 	Buf_AddByte(buf, (Byte)' ');
856 
857     addSpace = TRUE;
858 
859     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
860         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
861 	Str_SYSVSubst(buf, varexp, ptr, len);
862 	free(varexp);
863     } else {
864 	Buf_AddBytes(buf, strlen(word), (Byte *) word);
865     }
866 
867     return(addSpace);
868 }
869 #endif
870 
871 
872 /*-
873  *-----------------------------------------------------------------------
874  * VarNoMatch --
875  *	Place the word in the buffer if it doesn't match the given pattern.
876  *	Callback function for VarModify to implement the :N modifier.
877  *
878  * Results:
879  *	TRUE if a space should be placed in the buffer before the next
880  *	word.
881  *
882  * Side Effects:
883  *	The word may be copied to the buffer.
884  *
885  *-----------------------------------------------------------------------
886  */
887 static Boolean
888 VarNoMatch (ctx, word, addSpace, buf, pattern)
889     GNode	  *ctx;
890     char    	  *word;    	/* Word to examine */
891     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
892 				 * buffer before adding the word, if it
893 				 * matches */
894     Buffer  	  buf;	    	/* Buffer in which to store it */
895     ClientData    pattern; 	/* Pattern the word must match */
896 {
897     if (!Str_Match(word, (char *) pattern)) {
898 	if (addSpace) {
899 	    Buf_AddByte(buf, (Byte)' ');
900 	}
901 	addSpace = TRUE;
902 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
903     }
904     return(addSpace);
905 }
906 
907 
908 /*-
909  *-----------------------------------------------------------------------
910  * VarSubstitute --
911  *	Perform a string-substitution on the given word, placing the
912  *	result in the passed buffer.
913  *
914  * Results:
915  *	TRUE if a space is needed before more characters are added.
916  *
917  * Side Effects:
918  *	None.
919  *
920  *-----------------------------------------------------------------------
921  */
922 static Boolean
923 VarSubstitute (ctx, word, addSpace, buf, patternp)
924     GNode		*ctx;
925     char    	  	*word;	    /* Word to modify */
926     Boolean 	  	addSpace;   /* True if space should be added before
927 				     * other characters */
928     Buffer  	  	buf;	    /* Buffer for result */
929     ClientData	        patternp;   /* Pattern for substitution */
930 {
931     register int  	wordLen;    /* Length of word */
932     register char 	*cp;	    /* General pointer */
933     VarPattern	*pattern = (VarPattern *) patternp;
934 
935     wordLen = strlen(word);
936     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
937 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
938 	/*
939 	 * Still substituting -- break it down into simple anchored cases
940 	 * and if none of them fits, perform the general substitution case.
941 	 */
942 	if ((pattern->flags & VAR_MATCH_START) &&
943 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
944 		/*
945 		 * Anchored at start and beginning of word matches pattern
946 		 */
947 		if ((pattern->flags & VAR_MATCH_END) &&
948 		    (wordLen == pattern->leftLen)) {
949 			/*
950 			 * Also anchored at end and matches to the end (word
951 			 * is same length as pattern) add space and rhs only
952 			 * if rhs is non-null.
953 			 */
954 			if (pattern->rightLen != 0) {
955 			    if (addSpace) {
956 				Buf_AddByte(buf, (Byte)' ');
957 			    }
958 			    addSpace = TRUE;
959 			    Buf_AddBytes(buf, pattern->rightLen,
960 					 (Byte *)pattern->rhs);
961 			}
962 			pattern->flags |= VAR_SUB_MATCHED;
963 		} else if (pattern->flags & VAR_MATCH_END) {
964 		    /*
965 		     * Doesn't match to end -- copy word wholesale
966 		     */
967 		    goto nosub;
968 		} else {
969 		    /*
970 		     * Matches at start but need to copy in trailing characters
971 		     */
972 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
973 			if (addSpace) {
974 			    Buf_AddByte(buf, (Byte)' ');
975 			}
976 			addSpace = TRUE;
977 		    }
978 		    Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
979 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
980 				 (Byte *)(word + pattern->leftLen));
981 		    pattern->flags |= VAR_SUB_MATCHED;
982 		}
983 	} else if (pattern->flags & VAR_MATCH_START) {
984 	    /*
985 	     * Had to match at start of word and didn't -- copy whole word.
986 	     */
987 	    goto nosub;
988 	} else if (pattern->flags & VAR_MATCH_END) {
989 	    /*
990 	     * Anchored at end, Find only place match could occur (leftLen
991 	     * characters from the end of the word) and see if it does. Note
992 	     * that because the $ will be left at the end of the lhs, we have
993 	     * to use strncmp.
994 	     */
995 	    cp = word + (wordLen - pattern->leftLen);
996 	    if ((cp >= word) &&
997 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
998 		/*
999 		 * Match found. If we will place characters in the buffer,
1000 		 * add a space before hand as indicated by addSpace, then
1001 		 * stuff in the initial, unmatched part of the word followed
1002 		 * by the right-hand-side.
1003 		 */
1004 		if (((cp - word) + pattern->rightLen) != 0) {
1005 		    if (addSpace) {
1006 			Buf_AddByte(buf, (Byte)' ');
1007 		    }
1008 		    addSpace = TRUE;
1009 		}
1010 		Buf_AddBytes(buf, cp - word, (Byte *)word);
1011 		Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
1012 		pattern->flags |= VAR_SUB_MATCHED;
1013 	    } else {
1014 		/*
1015 		 * Had to match at end and didn't. Copy entire word.
1016 		 */
1017 		goto nosub;
1018 	    }
1019 	} else {
1020 	    /*
1021 	     * Pattern is unanchored: search for the pattern in the word using
1022 	     * String_FindSubstring, copying unmatched portions and the
1023 	     * right-hand-side for each match found, handling non-global
1024 	     * substitutions correctly, etc. When the loop is done, any
1025 	     * remaining part of the word (word and wordLen are adjusted
1026 	     * accordingly through the loop) is copied straight into the
1027 	     * buffer.
1028 	     * addSpace is set FALSE as soon as a space is added to the
1029 	     * buffer.
1030 	     */
1031 	    register Boolean done;
1032 	    int origSize;
1033 
1034 	    done = FALSE;
1035 	    origSize = Buf_Size(buf);
1036 	    while (!done) {
1037 		cp = Str_FindSubstring(word, pattern->lhs);
1038 		if (cp != (char *)NULL) {
1039 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
1040 			Buf_AddByte(buf, (Byte)' ');
1041 			addSpace = FALSE;
1042 		    }
1043 		    Buf_AddBytes(buf, cp-word, (Byte *)word);
1044 		    Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
1045 		    wordLen -= (cp - word) + pattern->leftLen;
1046 		    word = cp + pattern->leftLen;
1047 		    if (wordLen == 0) {
1048 			done = TRUE;
1049 		    }
1050 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
1051 			done = TRUE;
1052 		    }
1053 		    pattern->flags |= VAR_SUB_MATCHED;
1054 		} else {
1055 		    done = TRUE;
1056 		}
1057 	    }
1058 	    if (wordLen != 0) {
1059 		if (addSpace) {
1060 		    Buf_AddByte(buf, (Byte)' ');
1061 		}
1062 		Buf_AddBytes(buf, wordLen, (Byte *)word);
1063 	    }
1064 	    /*
1065 	     * If added characters to the buffer, need to add a space
1066 	     * before we add any more. If we didn't add any, just return
1067 	     * the previous value of addSpace.
1068 	     */
1069 	    return ((Buf_Size(buf) != origSize) || addSpace);
1070 	}
1071 	return (addSpace);
1072     }
1073  nosub:
1074     if (addSpace) {
1075 	Buf_AddByte(buf, (Byte)' ');
1076     }
1077     Buf_AddBytes(buf, wordLen, (Byte *)word);
1078     return(TRUE);
1079 }
1080 
1081 #ifndef NO_REGEX
1082 /*-
1083  *-----------------------------------------------------------------------
1084  * VarREError --
1085  *	Print the error caused by a regcomp or regexec call.
1086  *
1087  * Results:
1088  *	None.
1089  *
1090  * Side Effects:
1091  *	An error gets printed.
1092  *
1093  *-----------------------------------------------------------------------
1094  */
1095 static void
1096 VarREError(err, pat, str)
1097     int err;
1098     regex_t *pat;
1099     const char *str;
1100 {
1101     char *errbuf;
1102     int errlen;
1103 
1104     errlen = regerror(err, pat, 0, 0);
1105     errbuf = emalloc(errlen);
1106     regerror(err, pat, errbuf, errlen);
1107     Error("%s: %s", str, errbuf);
1108     free(errbuf);
1109 }
1110 
1111 
1112 /*-
1113  *-----------------------------------------------------------------------
1114  * VarRESubstitute --
1115  *	Perform a regex substitution on the given word, placing the
1116  *	result in the passed buffer.
1117  *
1118  * Results:
1119  *	TRUE if a space is needed before more characters are added.
1120  *
1121  * Side Effects:
1122  *	None.
1123  *
1124  *-----------------------------------------------------------------------
1125  */
1126 static Boolean
1127 VarRESubstitute(ctx, word, addSpace, buf, patternp)
1128     GNode *ctx;
1129     char *word;
1130     Boolean addSpace;
1131     Buffer buf;
1132     ClientData patternp;
1133 {
1134     VarREPattern *pat;
1135     int xrv;
1136     char *wp;
1137     char *rp;
1138     int added;
1139     int flags = 0;
1140 
1141 #define MAYBE_ADD_SPACE()		\
1142 	if (addSpace && !added)		\
1143 	    Buf_AddByte(buf, ' ');	\
1144 	added = 1
1145 
1146     added = 0;
1147     wp = word;
1148     pat = patternp;
1149 
1150     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1151 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1152 	xrv = REG_NOMATCH;
1153     else {
1154     tryagain:
1155 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1156     }
1157 
1158     switch (xrv) {
1159     case 0:
1160 	pat->flags |= VAR_SUB_MATCHED;
1161 	if (pat->matches[0].rm_so > 0) {
1162 	    MAYBE_ADD_SPACE();
1163 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1164 	}
1165 
1166 	for (rp = pat->replace; *rp; rp++) {
1167 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1168 		MAYBE_ADD_SPACE();
1169 		Buf_AddByte(buf,rp[1]);
1170 		rp++;
1171 	    }
1172 	    else if ((*rp == '&') ||
1173 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1174 		int n;
1175 		char *subbuf;
1176 		int sublen;
1177 		char errstr[3];
1178 
1179 		if (*rp == '&') {
1180 		    n = 0;
1181 		    errstr[0] = '&';
1182 		    errstr[1] = '\0';
1183 		} else {
1184 		    n = rp[1] - '0';
1185 		    errstr[0] = '\\';
1186 		    errstr[1] = rp[1];
1187 		    errstr[2] = '\0';
1188 		    rp++;
1189 		}
1190 
1191 		if (n > pat->nsub) {
1192 		    Error("No subexpression %s", &errstr[0]);
1193 		    subbuf = "";
1194 		    sublen = 0;
1195 		} else if ((pat->matches[n].rm_so == -1) &&
1196 			   (pat->matches[n].rm_eo == -1)) {
1197 		    Error("No match for subexpression %s", &errstr[0]);
1198 		    subbuf = "";
1199 		    sublen = 0;
1200 	        } else {
1201 		    subbuf = wp + pat->matches[n].rm_so;
1202 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1203 		}
1204 
1205 		if (sublen > 0) {
1206 		    MAYBE_ADD_SPACE();
1207 		    Buf_AddBytes(buf, sublen, subbuf);
1208 		}
1209 	    } else {
1210 		MAYBE_ADD_SPACE();
1211 		Buf_AddByte(buf, *rp);
1212 	    }
1213 	}
1214 	wp += pat->matches[0].rm_eo;
1215 	if (pat->flags & VAR_SUB_GLOBAL) {
1216 	    flags |= REG_NOTBOL;
1217 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1218 		MAYBE_ADD_SPACE();
1219 		Buf_AddByte(buf, *wp);
1220 		wp++;
1221 
1222 	    }
1223 	    if (*wp)
1224 		goto tryagain;
1225 	}
1226 	if (*wp) {
1227 	    MAYBE_ADD_SPACE();
1228 	    Buf_AddBytes(buf, strlen(wp), wp);
1229 	}
1230 	break;
1231     default:
1232 	VarREError(xrv, &pat->re, "Unexpected regex error");
1233        /* fall through */
1234     case REG_NOMATCH:
1235 	if (*wp) {
1236 	    MAYBE_ADD_SPACE();
1237 	    Buf_AddBytes(buf,strlen(wp),wp);
1238 	}
1239 	break;
1240     }
1241     return(addSpace||added);
1242 }
1243 #endif
1244 
1245 
1246 
1247 /*-
1248  *-----------------------------------------------------------------------
1249  * VarLoopExpand --
1250  *	Implements the :@<temp>@<string>@ modifier of ODE make.
1251  *	We set the temp variable named in pattern.lhs to word and expand
1252  *	pattern.rhs storing the result in the passed buffer.
1253  *
1254  * Results:
1255  *	TRUE if a space is needed before more characters are added.
1256  *
1257  * Side Effects:
1258  *	None.
1259  *
1260  *-----------------------------------------------------------------------
1261  */
1262 static Boolean
1263 VarLoopExpand (ctx, word, addSpace, buf, loopp)
1264     GNode		*ctx;
1265     char    	  	*word;	    /* Word to modify */
1266     Boolean 	  	addSpace;   /* True if space should be added before
1267 				     * other characters */
1268     Buffer  	  	buf;	    /* Buffer for result */
1269     ClientData	        loopp;      /* Data for substitution */
1270 {
1271     VarLoop_t	*loop = (VarLoop_t *) loopp;
1272     char *s;
1273     int slen;
1274 
1275     if (word && *word) {
1276         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
1277         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->err);
1278         if (s != NULL && *s != '\0') {
1279             if (addSpace && *s != '\n')
1280                 Buf_AddByte(buf, ' ');
1281             Buf_AddBytes(buf, (slen = strlen(s)), (Byte *)s);
1282             addSpace = (slen > 0 && s[slen - 1] != '\n');
1283             free(s);
1284         }
1285     }
1286     return addSpace;
1287 }
1288 
1289 /*-
1290  *-----------------------------------------------------------------------
1291  * VarModify --
1292  *	Modify each of the words of the passed string using the given
1293  *	function. Used to implement all modifiers.
1294  *
1295  * Results:
1296  *	A string of all the words modified appropriately.
1297  *
1298  * Side Effects:
1299  *	None.
1300  *
1301  *-----------------------------------------------------------------------
1302  */
1303 static char *
1304 VarModify (ctx, str, modProc, datum)
1305     GNode	  *ctx;
1306     char    	  *str;	    	    /* String whose words should be trimmed */
1307 				    /* Function to use to modify them */
1308     Boolean    	  (*modProc) __P((GNode *, char *, Boolean, Buffer,
1309 				  ClientData));
1310     ClientData	  datum;    	    /* Datum to pass it */
1311 {
1312     Buffer  	  buf;	    	    /* Buffer for the new string */
1313     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1314 				     * buffer before adding the trimmed
1315 				     * word */
1316     char **av;			    /* word list [first word does not count] */
1317     char *as;			    /* word list memory */
1318     int ac, i;
1319 
1320     buf = Buf_Init (0);
1321     addSpace = FALSE;
1322 
1323     av = brk_string(str, &ac, FALSE, &as);
1324 
1325     for (i = 0; i < ac; i++)
1326 	addSpace = (*modProc)(ctx, av[i], addSpace, buf, datum);
1327 
1328     free(as);
1329     free(av);
1330 
1331     Buf_AddByte (buf, '\0');
1332     str = (char *)Buf_GetAll (buf, (int *)NULL);
1333     Buf_Destroy (buf, FALSE);
1334     return (str);
1335 }
1336 
1337 
1338 static int
1339 VarWordCompare(a, b)
1340 	const void *a;
1341 	const void *b;
1342 {
1343 	int r = strcmp(*(char **)a, *(char **)b);
1344 	return r;
1345 }
1346 
1347 /*-
1348  *-----------------------------------------------------------------------
1349  * VarSort --
1350  *	Sort the words in the string.
1351  *
1352  * Results:
1353  *	A string containing the words sorted
1354  *
1355  * Side Effects:
1356  *	None.
1357  *
1358  *-----------------------------------------------------------------------
1359  */
1360 static char *
1361 VarSort (str)
1362     char    	  *str;	    	    /* String whose words should be sorted */
1363 				    /* Function to use to modify them */
1364 {
1365     Buffer  	  buf;	    	    /* Buffer for the new string */
1366     char **av;			    /* word list [first word does not count] */
1367     char *as;			    /* word list memory */
1368     int ac, i;
1369 
1370     buf = Buf_Init (0);
1371 
1372     av = brk_string(str, &ac, FALSE, &as);
1373 
1374     if (ac > 0)
1375 	qsort(av, ac, sizeof(char *), VarWordCompare);
1376 
1377     for (i = 0; i < ac; i++) {
1378 	Buf_AddBytes(buf, strlen(av[i]), (Byte *) av[i]);
1379 	if (i != ac - 1)
1380 	    Buf_AddByte (buf, ' ');
1381     }
1382 
1383     free(as);
1384     free(av);
1385 
1386     Buf_AddByte (buf, '\0');
1387     str = (char *)Buf_GetAll (buf, (int *)NULL);
1388     Buf_Destroy (buf, FALSE);
1389     return (str);
1390 }
1391 
1392 
1393 /*-
1394  *-----------------------------------------------------------------------
1395  * VarUniq --
1396  *	Remove adjacent duplicate words.
1397  *
1398  * Results:
1399  *	A string containing the resulting words.
1400  *
1401  * Side Effects:
1402  *	None.
1403  *
1404  *-----------------------------------------------------------------------
1405  */
1406 static char *
1407 VarUniq(str)
1408     char 	 *str;	    	    /* String whose words should be sorted */
1409 				    /* Function to use to modify them */
1410 {
1411     Buffer	  buf;	    	    /* Buffer for new string */
1412     char 	**av;		    /* List of words to affect */
1413     char 	 *as;		    /* Word list memory */
1414     int 	  ac, i, j;
1415 
1416     buf = Buf_Init(0);
1417     av = brk_string(str, &ac, FALSE, &as);
1418 
1419     if (ac > 1) {
1420 	for (j = 0, i = 1; i < ac; i++)
1421 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
1422 		av[j] = av[i];
1423 	ac = j + 1;
1424     }
1425 
1426     for (i = 0; i < ac; i++) {
1427 	Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1428 	if (i != ac - 1)
1429 	    Buf_AddByte(buf, ' ');
1430     }
1431 
1432     free(as);
1433     free(av);
1434 
1435     Buf_AddByte(buf, '\0');
1436     str = (char *)Buf_GetAll(buf, (int *)NULL);
1437     Buf_Destroy(buf, FALSE);
1438     return str;
1439 }
1440 
1441 
1442 /*-
1443  *-----------------------------------------------------------------------
1444  * VarGetPattern --
1445  *	Pass through the tstr looking for 1) escaped delimiters,
1446  *	'$'s and backslashes (place the escaped character in
1447  *	uninterpreted) and 2) unescaped $'s that aren't before
1448  *	the delimiter (expand the variable substitution unless flags
1449  *	has VAR_NOSUBST set).
1450  *	Return the expanded string or NULL if the delimiter was missing
1451  *	If pattern is specified, handle escaped ampersands, and replace
1452  *	unescaped ampersands with the lhs of the pattern.
1453  *
1454  * Results:
1455  *	A string of all the words modified appropriately.
1456  *	If length is specified, return the string length of the buffer
1457  *	If flags is specified and the last character of the pattern is a
1458  *	$ set the VAR_MATCH_END bit of flags.
1459  *
1460  * Side Effects:
1461  *	None.
1462  *-----------------------------------------------------------------------
1463  */
1464 static char *
1465 VarGetPattern(ctxt, err, tstr, delim, flags, length, pattern)
1466     GNode *ctxt;
1467     int err;
1468     char **tstr;
1469     int delim;
1470     int *flags;
1471     int *length;
1472     VarPattern *pattern;
1473 {
1474     char *cp;
1475     Buffer buf = Buf_Init(0);
1476     int junk;
1477     if (length == NULL)
1478 	length = &junk;
1479 
1480 #define IS_A_MATCH(cp, delim) \
1481     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
1482      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
1483 
1484     /*
1485      * Skim through until the matching delimiter is found;
1486      * pick up variable substitutions on the way. Also allow
1487      * backslashes to quote the delimiter, $, and \, but don't
1488      * touch other backslashes.
1489      */
1490     for (cp = *tstr; *cp && (*cp != delim); cp++) {
1491 	if (IS_A_MATCH(cp, delim)) {
1492 	    Buf_AddByte(buf, (Byte) cp[1]);
1493 	    cp++;
1494 	} else if (*cp == '$') {
1495 	    if (cp[1] == delim) {
1496 		if (flags == NULL)
1497 		    Buf_AddByte(buf, (Byte) *cp);
1498 		else
1499 		    /*
1500 		     * Unescaped $ at end of pattern => anchor
1501 		     * pattern at end.
1502 		     */
1503 		    *flags |= VAR_MATCH_END;
1504 	    } else {
1505 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
1506 		    char   *cp2;
1507 		    int     len;
1508 		    Boolean freeIt;
1509 
1510 		    /*
1511 		     * If unescaped dollar sign not before the
1512 		     * delimiter, assume it's a variable
1513 		     * substitution and recurse.
1514 		     */
1515 		    cp2 = Var_Parse(cp, ctxt, err, &len, &freeIt);
1516 		    Buf_AddBytes(buf, strlen(cp2), (Byte *) cp2);
1517 		    if (freeIt)
1518 			free(cp2);
1519 		    cp += len - 1;
1520 		} else {
1521 		    char *cp2 = &cp[1];
1522 
1523 		    if (*cp2 == '(' || *cp2 == '{') {
1524 			/*
1525 			 * Find the end of this variable reference
1526 			 * and suck it in without further ado.
1527 			 * It will be interperated later.
1528 			 */
1529 			int have = *cp2;
1530 			int want = (*cp2 == '(') ? ')' : '}';
1531 			int depth = 1;
1532 
1533 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
1534 			    if (cp2[-1] != '\\') {
1535 				if (*cp2 == have)
1536 				    ++depth;
1537 				if (*cp2 == want)
1538 				    --depth;
1539 			    }
1540 			}
1541 			Buf_AddBytes(buf, cp2 - cp, (Byte *)cp);
1542 			cp = --cp2;
1543 		    } else
1544 			Buf_AddByte(buf, (Byte) *cp);
1545 		}
1546 	    }
1547 	}
1548 	else if (pattern && *cp == '&')
1549 	    Buf_AddBytes(buf, pattern->leftLen, (Byte *)pattern->lhs);
1550 	else
1551 	    Buf_AddByte(buf, (Byte) *cp);
1552     }
1553 
1554     Buf_AddByte(buf, (Byte) '\0');
1555 
1556     if (*cp != delim) {
1557 	*tstr = cp;
1558 	*length = 0;
1559 	return NULL;
1560     }
1561     else {
1562 	*tstr = ++cp;
1563 	cp = (char *) Buf_GetAll(buf, length);
1564 	*length -= 1;	/* Don't count the NULL */
1565 	Buf_Destroy(buf, FALSE);
1566 	return cp;
1567     }
1568 }
1569 
1570 /*-
1571  *-----------------------------------------------------------------------
1572  * VarQuote --
1573  *	Quote shell meta-characters in the string
1574  *
1575  * Results:
1576  *	The quoted string
1577  *
1578  * Side Effects:
1579  *	None.
1580  *
1581  *-----------------------------------------------------------------------
1582  */
1583 static char *
1584 VarQuote(str)
1585 	char *str;
1586 {
1587 
1588     Buffer  	  buf;
1589     /* This should cover most shells :-( */
1590     static char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
1591 
1592     buf = Buf_Init (MAKE_BSIZE);
1593     for (; *str; str++) {
1594 	if (strchr(meta, *str) != NULL)
1595 	    Buf_AddByte(buf, (Byte)'\\');
1596 	Buf_AddByte(buf, (Byte)*str);
1597     }
1598     Buf_AddByte(buf, (Byte) '\0');
1599     str = (char *)Buf_GetAll (buf, (int *)NULL);
1600     Buf_Destroy (buf, FALSE);
1601     return str;
1602 }
1603 
1604 /*-
1605  *-----------------------------------------------------------------------
1606  * VarChangeCase --
1607  *      Change the string to all uppercase or all lowercase
1608  *
1609  * Results:
1610  *      The string with case changed
1611  *
1612  * Side Effects:
1613  *      None.
1614  *
1615  *-----------------------------------------------------------------------
1616  */
1617 static char *
1618 VarChangeCase(str, upper)
1619         char *str;                  /* String to modify */
1620         int upper;                  /* TRUE -> uppercase, else lowercase */
1621 {
1622    Buffer         buf;
1623    int            (*modProc) __P((int));
1624 
1625    modProc = (upper ? toupper : tolower);
1626    buf = Buf_Init (MAKE_BSIZE);
1627    for (; *str ; str++) {
1628        Buf_AddByte(buf, (Byte) modProc(*str));
1629    }
1630    Buf_AddByte(buf, (Byte) '\0');
1631    str = (char *) Buf_GetAll (buf, (int *) NULL);
1632    Buf_Destroy (buf, FALSE);
1633    return str;
1634 }
1635 
1636 /*-
1637  *-----------------------------------------------------------------------
1638  * Var_Parse --
1639  *	Given the start of a variable invocation, extract the variable
1640  *	name and find its value, then modify it according to the
1641  *	specification.
1642  *
1643  * Results:
1644  *	The (possibly-modified) value of the variable or var_Error if the
1645  *	specification is invalid. The length of the specification is
1646  *	placed in *lengthPtr (for invalid specifications, this is just
1647  *	2...?).
1648  *	A Boolean in *freePtr telling whether the returned string should
1649  *	be freed by the caller.
1650  *
1651  * Side Effects:
1652  *	None.
1653  *
1654  *-----------------------------------------------------------------------
1655  */
1656 char *
1657 Var_Parse (str, ctxt, err, lengthPtr, freePtr)
1658     char    	  *str;	    	/* The string to parse */
1659     GNode   	  *ctxt;    	/* The context for the variable */
1660     Boolean 	    err;    	/* TRUE if undefined variables are an error */
1661     int	    	    *lengthPtr;	/* OUT: The length of the specification */
1662     Boolean 	    *freePtr; 	/* OUT: TRUE if caller should free result */
1663 {
1664     register char   *tstr;    	/* Pointer into str */
1665     Var	    	    *v;	    	/* Variable in invocation */
1666     char   	    *cp;    	/* Secondary pointer into str (place marker
1667 				 * for tstr) */
1668     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
1669     register char   endc;    	/* Ending character when variable in parens
1670 				 * or braces */
1671     register char   startc=0;	/* Starting character when variable in parens
1672 				 * or braces */
1673     int             cnt;	/* Used to count brace pairs when variable in
1674 				 * in parens or braces */
1675     int		    vlen;	/* Length of variable name */
1676     char    	    *start;
1677     char	     delim;
1678     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
1679 				 * expanding it in a non-local context. This
1680 				 * is done to support dynamic sources. The
1681 				 * result is just the invocation, unaltered */
1682 
1683     *freePtr = FALSE;
1684     dynamic = FALSE;
1685     start = str;
1686 
1687     if (str[1] != '(' && str[1] != '{') {
1688 	/*
1689 	 * If it's not bounded by braces of some sort, life is much simpler.
1690 	 * We just need to check for the first character and return the
1691 	 * value if it exists.
1692 	 */
1693 	char	  name[2];
1694 
1695 	name[0] = str[1];
1696 	name[1] = '\0';
1697 
1698 	v = VarFind (name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1699 	if (v == (Var *)NIL) {
1700 	    *lengthPtr = 2;
1701 
1702 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
1703 		/*
1704 		 * If substituting a local variable in a non-local context,
1705 		 * assume it's for dynamic source stuff. We have to handle
1706 		 * this specially and return the longhand for the variable
1707 		 * with the dollar sign escaped so it makes it back to the
1708 		 * caller. Only four of the local variables are treated
1709 		 * specially as they are the only four that will be set
1710 		 * when dynamic sources are expanded.
1711 		 */
1712 		switch (str[1]) {
1713 		    case '@':
1714 			return("$(.TARGET)");
1715 		    case '%':
1716 			return("$(.ARCHIVE)");
1717 		    case '*':
1718 			return("$(.PREFIX)");
1719 		    case '!':
1720 			return("$(.MEMBER)");
1721 		}
1722 	    }
1723 	    /*
1724 	     * Error
1725 	     */
1726 	    return (err ? var_Error : varNoError);
1727 	} else {
1728 	    haveModifier = FALSE;
1729 	    tstr = &str[1];
1730 	    endc = str[1];
1731 	}
1732     } else {
1733 	Buffer buf;	/* Holds the variable name */
1734 
1735 	startc = str[1];
1736 	endc = startc == '(' ? ')' : '}';
1737 	buf = Buf_Init (MAKE_BSIZE);
1738 
1739 	/*
1740 	 * Skip to the end character or a colon, whichever comes first.
1741 	 */
1742 	for (tstr = str + 2;
1743 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
1744 	     tstr++)
1745 	{
1746 	    /*
1747 	     * A variable inside a variable, expand
1748 	     */
1749 	    if (*tstr == '$') {
1750 		int rlen;
1751 		Boolean rfree;
1752 		char *rval = Var_Parse(tstr, ctxt, err, &rlen, &rfree);
1753 		if (rval != NULL) {
1754 		    Buf_AddBytes(buf, strlen(rval), (Byte *) rval);
1755 		    if (rfree)
1756 			free(rval);
1757 		}
1758 		tstr += rlen - 1;
1759 	    }
1760 	    else
1761 		Buf_AddByte(buf, (Byte) *tstr);
1762 	}
1763 	if (*tstr == ':') {
1764 	    haveModifier = TRUE;
1765 	} else if (*tstr != '\0') {
1766 	    haveModifier = FALSE;
1767 	} else {
1768 	    /*
1769 	     * If we never did find the end character, return NULL
1770 	     * right now, setting the length to be the distance to
1771 	     * the end of the string, since that's what make does.
1772 	     */
1773 	    *lengthPtr = tstr - str;
1774 	    return (var_Error);
1775 	}
1776 	*tstr = '\0';
1777 	Buf_AddByte(buf, (Byte) '\0');
1778 	str = Buf_GetAll(buf, (int *) NULL);
1779 	vlen = strlen(str);
1780 
1781 	v = VarFind (str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1782 	if ((v == (Var *)NIL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
1783 	    (vlen == 2) && (str[1] == 'F' || str[1] == 'D'))
1784 	{
1785 	    /*
1786 	     * Check for bogus D and F forms of local variables since we're
1787 	     * in a local context and the name is the right length.
1788 	     */
1789 	    switch(*str) {
1790 		case '@':
1791 		case '%':
1792 		case '*':
1793 		case '!':
1794 		case '>':
1795 		case '<':
1796 		{
1797 		    char    vname[2];
1798 		    char    *val;
1799 
1800 		    /*
1801 		     * Well, it's local -- go look for it.
1802 		     */
1803 		    vname[0] = *str;
1804 		    vname[1] = '\0';
1805 		    v = VarFind(vname, ctxt, 0);
1806 
1807 		    if (v != (Var *)NIL) {
1808 			/*
1809 			 * No need for nested expansion or anything, as we're
1810 			 * the only one who sets these things and we sure don't
1811 			 * but nested invocations in them...
1812 			 */
1813 			val = (char *)Buf_GetAll(v->val, (int *)NULL);
1814 
1815 			if (str[1] == 'D') {
1816 			    val = VarModify(ctxt, val, VarHead, (ClientData)0);
1817 			} else {
1818 			    val = VarModify(ctxt, val, VarTail, (ClientData)0);
1819 			}
1820 			/*
1821 			 * Resulting string is dynamically allocated, so
1822 			 * tell caller to free it.
1823 			 */
1824 			*freePtr = TRUE;
1825 			*lengthPtr = tstr-start+1;
1826 			*tstr = endc;
1827 			Buf_Destroy (buf, TRUE);
1828 			return(val);
1829 		    }
1830 		    break;
1831 		}
1832 	    }
1833 	}
1834 
1835 	if (v == (Var *)NIL) {
1836 	    if (((vlen == 1) ||
1837 		 (((vlen == 2) && (str[1] == 'F' ||
1838 					 str[1] == 'D')))) &&
1839 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
1840 	    {
1841 		/*
1842 		 * If substituting a local variable in a non-local context,
1843 		 * assume it's for dynamic source stuff. We have to handle
1844 		 * this specially and return the longhand for the variable
1845 		 * with the dollar sign escaped so it makes it back to the
1846 		 * caller. Only four of the local variables are treated
1847 		 * specially as they are the only four that will be set
1848 		 * when dynamic sources are expanded.
1849 		 */
1850 		switch (*str) {
1851 		    case '@':
1852 		    case '%':
1853 		    case '*':
1854 		    case '!':
1855 			dynamic = TRUE;
1856 			break;
1857 		}
1858 	    } else if ((vlen > 2) && (*str == '.') &&
1859 		       isupper((unsigned char) str[1]) &&
1860 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
1861 	    {
1862 		int	len;
1863 
1864 		len = vlen - 1;
1865 		if ((strncmp(str, ".TARGET", len) == 0) ||
1866 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
1867 		    (strncmp(str, ".PREFIX", len) == 0) ||
1868 		    (strncmp(str, ".MEMBER", len) == 0))
1869 		{
1870 		    dynamic = TRUE;
1871 		}
1872 	    }
1873 
1874 	    if (!haveModifier) {
1875 		/*
1876 		 * No modifiers -- have specification length so we can return
1877 		 * now.
1878 		 */
1879 		*lengthPtr = tstr - start + 1;
1880 		*tstr = endc;
1881 		if (dynamic) {
1882 		    str = emalloc(*lengthPtr + 1);
1883 		    strncpy(str, start, *lengthPtr);
1884 		    str[*lengthPtr] = '\0';
1885 		    *freePtr = TRUE;
1886 		    Buf_Destroy (buf, TRUE);
1887 		    return(str);
1888 		} else {
1889 		    Buf_Destroy (buf, TRUE);
1890 		    return (err ? var_Error : varNoError);
1891 		}
1892 	    } else {
1893 		/*
1894 		 * Still need to get to the end of the variable specification,
1895 		 * so kludge up a Var structure for the modifications
1896 		 */
1897 		v = (Var *) emalloc(sizeof(Var));
1898 		v->name = str;
1899 		v->val = Buf_Init(1);
1900 		v->flags = VAR_JUNK;
1901 		Buf_Destroy (buf, FALSE);
1902 	    }
1903 	} else
1904 	    Buf_Destroy (buf, TRUE);
1905     }
1906 
1907 
1908     if (v->flags & VAR_IN_USE) {
1909 	Fatal("Variable %s is recursive.", v->name);
1910 	/*NOTREACHED*/
1911     } else {
1912 	v->flags |= VAR_IN_USE;
1913     }
1914     /*
1915      * Before doing any modification, we have to make sure the value
1916      * has been fully expanded. If it looks like recursion might be
1917      * necessary (there's a dollar sign somewhere in the variable's value)
1918      * we just call Var_Subst to do any other substitutions that are
1919      * necessary. Note that the value returned by Var_Subst will have
1920      * been dynamically-allocated, so it will need freeing when we
1921      * return.
1922      */
1923     str = (char *)Buf_GetAll(v->val, (int *)NULL);
1924     if (strchr (str, '$') != (char *)NULL) {
1925 	str = Var_Subst(NULL, str, ctxt, err);
1926 	*freePtr = TRUE;
1927     }
1928 
1929     v->flags &= ~VAR_IN_USE;
1930 
1931     /*
1932      * Now we need to apply any modifiers the user wants applied.
1933      * These are:
1934      *  	  :M<pattern>	words which match the given <pattern>.
1935      *  	  	    	<pattern> is of the standard file
1936      *  	  	    	wildcarding form.
1937      *  	  :N<pattern>	words which do not match the given <pattern>.
1938      *  	  :S<d><pat1><d><pat2><d>[g]
1939      *  	  	    	Substitute <pat2> for <pat1> in the value
1940      *  	  :C<d><pat1><d><pat2><d>[g]
1941      *  	  	    	Substitute <pat2> for regex <pat1> in the value
1942      *  	  :H	    	Substitute the head of each word
1943      *  	  :T	    	Substitute the tail of each word
1944      *  	  :E	    	Substitute the extension (minus '.') of
1945      *  	  	    	each word
1946      *  	  :R	    	Substitute the root of each word
1947      *  	  	    	(pathname minus the suffix).
1948      *		  :O		("Order") Sort words in variable.
1949      *		  :u		("uniq") Remove adjacent duplicate words.
1950      *		  :tu		Converts the variable contents to uppercase.
1951      *		  :tl		Converts the variable contents to lowercase.
1952      *		  :?<true-value>:<false-value>
1953      *				If the variable evaluates to true, return
1954      *				true value, else return the second value.
1955      *	    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
1956      *	    	    	    	the invocation.
1957      *		  :sh		Treat the current value as a command
1958      *				to be run, new value is its output.
1959      * The following added so we can handle ODE makefiles.
1960      *		  :@<tmpvar>@<newval>@
1961      *				Assign a temporary local variable <tmpvar>
1962      *				to the current value of each word in turn
1963      *				and replace each word with the result of
1964      *				evaluating <newval>
1965      *		  :D<newval>	Use <newval> as value if variable defined
1966      *		  :U<newval>	Use <newval> as value if variable undefined
1967      *		  :L		Use the name of the variable as the value.
1968      *		  :P		Use the path of the node that has the same
1969      *				name as the variable as the value.  This
1970      *				basically includes an implied :L so that
1971      *				the common method of refering to the path
1972      *				of your dependent 'x' in a rule is to use
1973      *				the form '${x:P}'.
1974      *		  :!<cmd>!	Run cmd much the same as :sh run's the
1975      *				current value of the variable.
1976      * The ::= modifiers, actually assign a value to the variable.
1977      * Their main purpose is in supporting modifiers of .for loop
1978      * iterators and other obscure uses.  They always expand to
1979      * nothing.  In a target rule that would otherwise expand to an
1980      * empty line they can be preceded with @: to keep make happy.
1981      * Eg.
1982      *
1983      * foo:	.USE
1984      * .for i in ${.TARGET} ${.TARGET:R}.gz
1985      * 		@: ${t::=$i}
1986      *		@echo blah ${t:T}
1987      * .endfor
1988      *
1989      *		  ::=<str>	Assigns <str> as the new value of variable.
1990      *		  ::?=<str>	Assigns <str> as value of variable if
1991      *				it was not already set.
1992      *		  ::+=<str>	Appends <str> to variable.
1993      *		  ::!=<cmd>	Assigns output of <cmd> as the new value of
1994      *				variable.
1995      */
1996     if ((str != (char *)NULL) && haveModifier) {
1997 	/*
1998 	 * Skip initial colon while putting it back.
1999 	 */
2000 	*tstr++ = ':';
2001 	while (*tstr != endc) {
2002 	    char	*newStr;    /* New value to return */
2003 	    char	termc;	    /* Character which terminated scan */
2004 
2005 	    if (DEBUG(VAR)) {
2006 		printf("Applying :%c to \"%s\"\n", *tstr, str);
2007 	    }
2008 	    switch (*tstr) {
2009 	        case ':':
2010 
2011 		if (tstr[1] == '=' ||
2012 		    (tstr[2] == '=' &&
2013 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
2014 		    GNode *v_ctxt;		/* context where v belongs */
2015 		    char *emsg;
2016 		    VarPattern	pattern;
2017 		    int	how;
2018 
2019 		    ++tstr;
2020 		    if (v->flags & VAR_JUNK) {
2021 			/*
2022 			 * We need to strdup() it incase
2023 			 * VarGetPattern() recurses.
2024 			 */
2025 			v->name = strdup(v->name);
2026 			v_ctxt = ctxt;
2027 		    } else if (ctxt != VAR_GLOBAL) {
2028 			if (VarFind(v->name, ctxt, 0) == (Var *)NIL)
2029 			    v_ctxt = VAR_GLOBAL;
2030 			else
2031 			    v_ctxt = ctxt;
2032 		    }
2033 
2034 		    switch ((how = *tstr)) {
2035 		    case '+':
2036 		    case '?':
2037 		    case '!':
2038 			cp = &tstr[2];
2039 			break;
2040 		    default:
2041 			cp = ++tstr;
2042 			break;
2043 		    }
2044 			/* '{' */
2045 		    delim = '}';
2046 		    pattern.flags = 0;
2047 
2048 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
2049 						     NULL, &pattern.rightLen, NULL)) == NULL) {
2050 			if (v->flags & VAR_JUNK) {
2051 			    free(v->name);
2052 			    v->name = str;
2053 			}
2054 			goto cleanup;
2055 		    }
2056 		    termc = *--cp;
2057 		    delim = '\0';
2058 
2059 		    switch (how) {
2060 		    case '+':
2061 			Var_Append(v->name, pattern.rhs, v_ctxt);
2062 			break;
2063 		    case '!':
2064 			newStr = Cmd_Exec (pattern.rhs, &emsg);
2065 			if (emsg)
2066 			    Error (emsg, str);
2067 			else
2068 			   Var_Set(v->name, newStr,  v_ctxt, 0);
2069 			if (newStr)
2070 			    free(newStr);
2071 			break;
2072 		    case '?':
2073 			if ((v->flags & VAR_JUNK) == 0)
2074 			    break;
2075 			/* FALLTHROUGH */
2076 		    default:
2077 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
2078 			break;
2079 		    }
2080 		    if (v->flags & VAR_JUNK) {
2081 			free(v->name);
2082 			v->name = str;
2083 		    }
2084 		    free(pattern.rhs);
2085 		    newStr = var_Error;
2086 		    break;
2087 		}
2088 		goto default_case;
2089 	        case '@':
2090 		{
2091 		    VarLoop_t	loop;
2092 		    int flags = VAR_NOSUBST;
2093 
2094 		    cp = ++tstr;
2095 		    delim = '@';
2096 		    if ((loop.tvar = VarGetPattern(ctxt, err, &cp, delim,
2097 						   &flags, &loop.tvarLen,
2098 						   NULL)) == NULL)
2099 			goto cleanup;
2100 
2101 		    if ((loop.str = VarGetPattern(ctxt, err, &cp, delim,
2102 						  &flags, &loop.strLen,
2103 						  NULL)) == NULL)
2104 			goto cleanup;
2105 
2106 		    termc = *cp;
2107 		    delim = '\0';
2108 
2109 		    loop.err = err;
2110 		    loop.ctxt = ctxt;
2111 		    newStr = VarModify(ctxt, str, VarLoopExpand,
2112 				       (ClientData)&loop);
2113 		    free(loop.tvar);
2114 		    free(loop.str);
2115 		    break;
2116 		}
2117 	        case 'D':
2118 	        case 'U':
2119 		{
2120 		    Buffer  buf;    	/* Buffer for patterns */
2121 		    int	    wantit;	/* want data in buffer */
2122 
2123 		    /*
2124 		     * Pass through tstr looking for 1) escaped delimiters,
2125 		     * '$'s and backslashes (place the escaped character in
2126 		     * uninterpreted) and 2) unescaped $'s that aren't before
2127 		     * the delimiter (expand the variable substitution).
2128 		     * The result is left in the Buffer buf.
2129 		     */
2130 		    buf = Buf_Init(0);
2131 		    for (cp = tstr + 1;
2132 			 *cp != endc && *cp != ':' && *cp != '\0';
2133 			 cp++) {
2134 			if ((*cp == '\\') &&
2135 			    ((cp[1] == ':') ||
2136 			     (cp[1] == '$') ||
2137 			     (cp[1] == endc) ||
2138 			     (cp[1] == '\\')))
2139 			{
2140 			    Buf_AddByte(buf, (Byte) cp[1]);
2141 			    cp++;
2142 			} else if (*cp == '$') {
2143 			    /*
2144 			     * If unescaped dollar sign, assume it's a
2145 			     * variable substitution and recurse.
2146 			     */
2147 			    char    *cp2;
2148 			    int	    len;
2149 			    Boolean freeIt;
2150 
2151 			    cp2 = Var_Parse(cp, ctxt, err, &len, &freeIt);
2152 			    Buf_AddBytes(buf, strlen(cp2), (Byte *) cp2);
2153 			    if (freeIt)
2154 				free(cp2);
2155 			    cp += len - 1;
2156 			} else {
2157 			    Buf_AddByte(buf, (Byte) *cp);
2158 			}
2159 		    }
2160 		    Buf_AddByte(buf, (Byte) '\0');
2161 
2162 		    termc = *cp;
2163 
2164 		    if (*tstr == 'U')
2165 			wantit = ((v->flags & VAR_JUNK) != 0);
2166 		    else
2167 			wantit = ((v->flags & VAR_JUNK) == 0);
2168 		    if ((v->flags & VAR_JUNK) != 0)
2169 			v->flags |= VAR_KEEP;
2170 		    if (wantit) {
2171 			newStr = (char *)Buf_GetAll(buf, (int *)NULL);
2172 			Buf_Destroy(buf, FALSE);
2173 		    } else {
2174 			newStr = str;
2175 			Buf_Destroy(buf, TRUE);
2176 		    }
2177 		    break;
2178 		}
2179 	        case 'L':
2180 		{
2181 		    if ((v->flags & VAR_JUNK) != 0)
2182 			v->flags |= VAR_KEEP;
2183 		    newStr = strdup(v->name);
2184 		    cp = ++tstr;
2185 		    termc = *tstr;
2186 		    break;
2187 		}
2188 	        case 'P':
2189 		{
2190 		    GNode *gn;
2191 
2192 		    if ((v->flags & VAR_JUNK) != 0)
2193 			v->flags |= VAR_KEEP;
2194 		    gn = Targ_FindNode(v->name, TARG_NOCREATE);
2195 		    if (gn == NILGNODE || gn->path == NULL)
2196 			newStr = strdup(v->name);
2197 		    else
2198 			newStr = strdup(gn->path);
2199 		    cp = ++tstr;
2200 		    termc = *tstr;
2201 		    break;
2202 		}
2203 	        case '!':
2204 		{
2205 		    char *emsg;
2206 		    VarPattern 	    pattern;
2207 		    pattern.flags = 0;
2208 
2209 		    delim = '!';
2210 
2211 		    cp = ++tstr;
2212 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
2213 						     NULL, &pattern.rightLen, NULL)) == NULL)
2214 			goto cleanup;
2215 		    newStr = Cmd_Exec (pattern.rhs, &emsg);
2216 		    free(pattern.rhs);
2217 		    if (emsg)
2218 			Error (emsg, str);
2219 		    termc = *cp;
2220 		    delim = '\0';
2221 		    if (v->flags & VAR_JUNK) {
2222 			v->flags |= VAR_KEEP;
2223 		    }
2224 		    break;
2225 		}
2226 	        case 't':
2227 		{
2228 		    if (tstr[1] != endc && tstr[1] != ':') {
2229 		        if (tstr[2] == endc || tstr[2] == ':') {
2230                             if (tstr[1] == 'u' || tstr[1] == 'l') {
2231                                 newStr = VarChangeCase (str, (tstr[1] == 'u'));
2232                                 cp = tstr + 2;
2233                                 termc = *cp;
2234                             }
2235 		        }
2236 		    }
2237 		    break;
2238 		}
2239 		case 'N':
2240 		case 'M':
2241 		{
2242 		    char    *pattern;
2243 		    char    *cp2;
2244 		    Boolean copy;
2245 		    int nest;
2246 
2247 		    copy = FALSE;
2248 		    nest = 1;
2249 		    for (cp = tstr + 1;
2250 			 *cp != '\0' && *cp != ':';
2251 			 cp++)
2252 		    {
2253 			if (*cp == '\\' &&
2254 			    (cp[1] == ':' ||
2255 			     cp[1] == endc || cp[1] == startc)) {
2256 			    copy = TRUE;
2257 			    cp++;
2258 			    continue;
2259 			}
2260 			if (*cp == startc)
2261 			    ++nest;
2262 			if (*cp == endc) {
2263 			    --nest;
2264 			    if (nest == 0)
2265 				break;
2266 			}
2267 		    }
2268 		    termc = *cp;
2269 		    *cp = '\0';
2270 		    if (copy) {
2271 			/*
2272 			 * Need to compress the \:'s out of the pattern, so
2273 			 * allocate enough room to hold the uncompressed
2274 			 * pattern (note that cp started at tstr+1, so
2275 			 * cp - tstr takes the null byte into account) and
2276 			 * compress the pattern into the space.
2277 			 */
2278 			pattern = emalloc(cp - tstr);
2279 			for (cp2 = pattern, cp = tstr + 1;
2280 			     *cp != '\0';
2281 			     cp++, cp2++)
2282 			{
2283 			    if ((*cp == '\\') &&
2284 				(cp[1] == ':' || cp[1] == endc)) {
2285 				    cp++;
2286 			    }
2287 			    *cp2 = *cp;
2288 			}
2289 			*cp2 = '\0';
2290 		    } else {
2291 			pattern = &tstr[1];
2292 		    }
2293 		    if ((cp2 = strchr(pattern, '$'))) {
2294 			cp2 = pattern;
2295 			pattern = Var_Subst(NULL, cp2, ctxt, err);
2296 			if (copy)
2297 			    free(cp2);
2298 			copy = TRUE;
2299 		    }
2300 		    if (*tstr == 'M' || *tstr == 'm') {
2301 			newStr = VarModify(ctxt, str, VarMatch, (ClientData)pattern);
2302 		    } else {
2303 			newStr = VarModify(ctxt, str, VarNoMatch,
2304 					   (ClientData)pattern);
2305 		    }
2306 		    if (copy) {
2307 			free(pattern);
2308 		    }
2309 		    break;
2310 		}
2311 		case 'S':
2312 		{
2313 		    VarPattern 	    pattern;
2314 
2315 		    pattern.flags = 0;
2316 		    delim = tstr[1];
2317 		    tstr += 2;
2318 
2319 		    /*
2320 		     * If pattern begins with '^', it is anchored to the
2321 		     * start of the word -- skip over it and flag pattern.
2322 		     */
2323 		    if (*tstr == '^') {
2324 			pattern.flags |= VAR_MATCH_START;
2325 			tstr += 1;
2326 		    }
2327 
2328 		    cp = tstr;
2329 		    if ((pattern.lhs = VarGetPattern(ctxt, err, &cp, delim,
2330 			&pattern.flags, &pattern.leftLen, NULL)) == NULL)
2331 			goto cleanup;
2332 
2333 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
2334 			NULL, &pattern.rightLen, &pattern)) == NULL)
2335 			goto cleanup;
2336 
2337 		    /*
2338 		     * Check for global substitution. If 'g' after the final
2339 		     * delimiter, substitution is global and is marked that
2340 		     * way.
2341 		     */
2342 		    for (;; cp++) {
2343 			switch (*cp) {
2344 			case 'g':
2345 			    pattern.flags |= VAR_SUB_GLOBAL;
2346 			    continue;
2347 			case '1':
2348 			    pattern.flags |= VAR_SUB_ONE;
2349 			    continue;
2350 			}
2351 			break;
2352 		    }
2353 
2354 		    termc = *cp;
2355 		    newStr = VarModify(ctxt, str, VarSubstitute,
2356 				       (ClientData)&pattern);
2357 
2358 		    /*
2359 		     * Free the two strings.
2360 		     */
2361 		    free(pattern.lhs);
2362 		    free(pattern.rhs);
2363 		    break;
2364 		}
2365 		case '?':
2366 		{
2367 		    VarPattern 	pattern;
2368 		    Boolean	value;
2369 
2370 		    /* find ':', and then substitute accordingly */
2371 
2372 		    pattern.flags = 0;
2373 
2374 		    cp = ++tstr;
2375 		    delim = ':';
2376 		    if ((pattern.lhs = VarGetPattern(ctxt, err, &cp, delim,
2377 			NULL, &pattern.leftLen, NULL)) == NULL)
2378 			goto cleanup;
2379 
2380 			/* '{' */
2381 		    delim = '}';
2382 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
2383 			NULL, &pattern.rightLen, NULL)) == NULL)
2384 			goto cleanup;
2385 
2386 		    termc = *--cp;
2387 		    delim = '\0';
2388 		    if (Cond_EvalExpression(1, v->name, &value, 0)
2389 			== COND_INVALID) {
2390 			Error("Bad conditional expression `%s' in %s?%s:%s",
2391 			      v->name, v->name, pattern.lhs, pattern.rhs);
2392 			goto cleanup;
2393 		    }
2394 
2395 		    if (value) {
2396 			newStr = pattern.lhs;
2397 			free(pattern.rhs);
2398 		    } else {
2399 			newStr = pattern.rhs;
2400 			free(pattern.lhs);
2401 		    }
2402 		    break;
2403 		}
2404 #ifndef NO_REGEX
2405 		case 'C':
2406 		{
2407 		    VarREPattern    pattern;
2408 		    char           *re;
2409 		    int             error;
2410 
2411 		    pattern.flags = 0;
2412 		    delim = tstr[1];
2413 		    tstr += 2;
2414 
2415 		    cp = tstr;
2416 
2417 		    if ((re = VarGetPattern(ctxt, err, &cp, delim, NULL,
2418 			NULL, NULL)) == NULL)
2419 			goto cleanup;
2420 
2421 		    if ((pattern.replace = VarGetPattern(ctxt, err, &cp,
2422 			delim, NULL, NULL, NULL)) == NULL){
2423 			free(re);
2424 			goto cleanup;
2425 		    }
2426 
2427 		    for (;; cp++) {
2428 			switch (*cp) {
2429 			case 'g':
2430 			    pattern.flags |= VAR_SUB_GLOBAL;
2431 			    continue;
2432 			case '1':
2433 			    pattern.flags |= VAR_SUB_ONE;
2434 			    continue;
2435 			}
2436 			break;
2437 		    }
2438 
2439 		    termc = *cp;
2440 
2441 		    error = regcomp(&pattern.re, re, REG_EXTENDED);
2442 		    free(re);
2443 		    if (error)  {
2444 			*lengthPtr = cp - start + 1;
2445 			VarREError(error, &pattern.re, "RE substitution error");
2446 			free(pattern.replace);
2447 			return (var_Error);
2448 		    }
2449 
2450 		    pattern.nsub = pattern.re.re_nsub + 1;
2451 		    if (pattern.nsub < 1)
2452 			pattern.nsub = 1;
2453 		    if (pattern.nsub > 10)
2454 			pattern.nsub = 10;
2455 		    pattern.matches = emalloc(pattern.nsub *
2456 					      sizeof(regmatch_t));
2457 		    newStr = VarModify(ctxt, str, VarRESubstitute,
2458 				       (ClientData) &pattern);
2459 		    regfree(&pattern.re);
2460 		    free(pattern.replace);
2461 		    free(pattern.matches);
2462 		    break;
2463 		}
2464 #endif
2465 		case 'Q':
2466 		    if (tstr[1] == endc || tstr[1] == ':') {
2467 			newStr = VarQuote (str);
2468 			cp = tstr + 1;
2469 			termc = *cp;
2470 			break;
2471 		    }
2472 		    /*FALLTHRU*/
2473 		case 'T':
2474 		    if (tstr[1] == endc || tstr[1] == ':') {
2475 			newStr = VarModify(ctxt, str, VarTail, (ClientData)0);
2476 			cp = tstr + 1;
2477 			termc = *cp;
2478 			break;
2479 		    }
2480 		    /*FALLTHRU*/
2481 		case 'H':
2482 		    if (tstr[1] == endc || tstr[1] == ':') {
2483 			newStr = VarModify(ctxt, str, VarHead, (ClientData)0);
2484 			cp = tstr + 1;
2485 			termc = *cp;
2486 			break;
2487 		    }
2488 		    /*FALLTHRU*/
2489 		case 'E':
2490 		    if (tstr[1] == endc || tstr[1] == ':') {
2491 			newStr = VarModify(ctxt, str, VarSuffix, (ClientData)0);
2492 			cp = tstr + 1;
2493 			termc = *cp;
2494 			break;
2495 		    }
2496 		    /*FALLTHRU*/
2497 		case 'R':
2498 		    if (tstr[1] == endc || tstr[1] == ':') {
2499 			newStr = VarModify(ctxt, str, VarRoot, (ClientData)0);
2500 			cp = tstr + 1;
2501 			termc = *cp;
2502 			break;
2503 		    }
2504 		    /*FALLTHRU*/
2505 		case 'O':
2506 		    if (tstr[1] == endc || tstr[1] == ':') {
2507 			newStr = VarSort (str);
2508 			cp = tstr + 1;
2509 			termc = *cp;
2510 			break;
2511 		    }
2512 		    /*FALLTHRU*/
2513 		case 'u':
2514 		    if (tstr[1] == endc || tstr[1] == ':') {
2515 			newStr = VarUniq (str);
2516 			cp = tstr + 1;
2517 			termc = *cp;
2518 			break;
2519 		    }
2520 		    /*FALLTHRU*/
2521 #ifdef SUNSHCMD
2522 		case 's':
2523 		    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
2524 			char *errstr;
2525 			newStr = Cmd_Exec (str, &errstr);
2526 			if (errstr)
2527 			    Error (errstr, str);
2528 			cp = tstr + 2;
2529 			termc = *cp;
2530 			break;
2531 		    }
2532 		    /*FALLTHRU*/
2533 #endif
2534                 default:
2535 		default_case:
2536 		{
2537 #ifdef SYSVVARSUB
2538 		    /*
2539 		     * This can either be a bogus modifier or a System-V
2540 		     * substitution command.
2541 		     */
2542 		    VarPattern      pattern;
2543 		    Boolean         eqFound;
2544 
2545 		    pattern.flags = 0;
2546 		    eqFound = FALSE;
2547 		    /*
2548 		     * First we make a pass through the string trying
2549 		     * to verify it is a SYSV-make-style translation:
2550 		     * it must be: <string1>=<string2>)
2551 		     */
2552 		    cp = tstr;
2553 		    cnt = 1;
2554 		    while (*cp != '\0' && cnt) {
2555 			if (*cp == '=') {
2556 			    eqFound = TRUE;
2557 			    /* continue looking for endc */
2558 			}
2559 			else if (*cp == endc)
2560 			    cnt--;
2561 			else if (*cp == startc)
2562 			    cnt++;
2563 			if (cnt)
2564 			    cp++;
2565 		    }
2566 		    if (*cp == endc && eqFound) {
2567 
2568 			/*
2569 			 * Now we break this sucker into the lhs and
2570 			 * rhs. We must null terminate them of course.
2571 			 */
2572 			for (cp = tstr; *cp != '='; cp++)
2573 			    continue;
2574 			pattern.lhs = tstr;
2575 			pattern.leftLen = cp - tstr;
2576 			*cp++ = '\0';
2577 
2578 			pattern.rhs = cp;
2579 			cnt = 1;
2580 			while (cnt) {
2581 			    if (*cp == endc)
2582 				cnt--;
2583 			    else if (*cp == startc)
2584 				cnt++;
2585 			    if (cnt)
2586 				cp++;
2587 			}
2588 			pattern.rightLen = cp - pattern.rhs;
2589 			*cp = '\0';
2590 
2591 			/*
2592 			 * SYSV modifications happen through the whole
2593 			 * string. Note the pattern is anchored at the end.
2594 			 */
2595 			newStr = VarModify(ctxt, str, VarSYSVMatch,
2596 					   (ClientData)&pattern);
2597 
2598 			/*
2599 			 * Restore the nulled characters
2600 			 */
2601 			pattern.lhs[pattern.leftLen] = '=';
2602 			pattern.rhs[pattern.rightLen] = endc;
2603 			termc = endc;
2604 		    } else
2605 #endif
2606 		    {
2607 			Error ("Unknown modifier '%c'", *tstr);
2608 			for (cp = tstr+1;
2609 			     *cp != ':' && *cp != endc && *cp != '\0';
2610 			     cp++)
2611 				 continue;
2612 			termc = *cp;
2613 			newStr = var_Error;
2614 		    }
2615 		}
2616 	    }
2617 	    if (DEBUG(VAR)) {
2618 		printf("Result is \"%s\"\n", newStr);
2619 	    }
2620 
2621 	    if (newStr != str) {
2622 		if (*freePtr) {
2623 		    free (str);
2624 		}
2625 		str = newStr;
2626 		if (str != var_Error && str != varNoError) {
2627 		    *freePtr = TRUE;
2628 		} else {
2629 		    *freePtr = FALSE;
2630 		}
2631 	    }
2632 	    if (termc == '\0') {
2633 		Error("Unclosed variable specification for %s", v->name);
2634 	    } else if (termc == ':') {
2635 		*cp++ = termc;
2636 	    } else {
2637 		*cp = termc;
2638 	    }
2639 	    tstr = cp;
2640 	}
2641 	*lengthPtr = tstr - start + 1;
2642     } else {
2643 	*lengthPtr = tstr - start + 1;
2644 	*tstr = endc;
2645     }
2646 
2647     if (v->flags & VAR_FROM_ENV) {
2648 	Boolean	  destroy = FALSE;
2649 
2650 	if (str != (char *)Buf_GetAll(v->val, (int *)NULL)) {
2651 	    destroy = TRUE;
2652 	} else {
2653 	    /*
2654 	     * Returning the value unmodified, so tell the caller to free
2655 	     * the thing.
2656 	     */
2657 	    *freePtr = TRUE;
2658 	}
2659 	if (str != (char *)Buf_GetAll(v->val, (int *)NULL))
2660 	    Buf_Destroy(v->val, destroy);
2661 	free((Address)v->name);
2662 	free((Address)v);
2663     } else if (v->flags & VAR_JUNK) {
2664 	/*
2665 	 * Perform any free'ing needed and set *freePtr to FALSE so the caller
2666 	 * doesn't try to free a static pointer.
2667 	 * If VAR_KEEP is also set then we want to keep str as is.
2668 	 */
2669 	if (!(v->flags & VAR_KEEP)) {
2670 	    if (*freePtr) {
2671 		free(str);
2672 	    }
2673 	    *freePtr = FALSE;
2674 	    if (dynamic) {
2675 		str = emalloc(*lengthPtr + 1);
2676 		strncpy(str, start, *lengthPtr);
2677 		str[*lengthPtr] = '\0';
2678 		*freePtr = TRUE;
2679 	    } else {
2680 		str = var_Error;
2681 	    }
2682 	}
2683 	if (str != (char *)Buf_GetAll(v->val, (int *)NULL))
2684 	    Buf_Destroy(v->val, TRUE);
2685 	free((Address)v->name);
2686 	free((Address)v);
2687     }
2688     return (str);
2689 
2690 cleanup:
2691     *lengthPtr = cp - start + 1;
2692     if (*freePtr)
2693 	free(str);
2694     if (delim != '\0')
2695 	Error("Unclosed substitution for %s (%c missing)",
2696 	      v->name, delim);
2697     return (var_Error);
2698 }
2699 
2700 /*-
2701  *-----------------------------------------------------------------------
2702  * Var_Subst  --
2703  *	Substitute for all variables in the given string in the given context
2704  *	If undefErr is TRUE, Parse_Error will be called when an undefined
2705  *	variable is encountered.
2706  *
2707  * Results:
2708  *	The resulting string.
2709  *
2710  * Side Effects:
2711  *	None. The old string must be freed by the caller
2712  *-----------------------------------------------------------------------
2713  */
2714 char *
2715 Var_Subst (var, str, ctxt, undefErr)
2716     char	  *var;		    /* Named variable || NULL for all */
2717     char 	  *str;	    	    /* the string in which to substitute */
2718     GNode         *ctxt;	    /* the context wherein to find variables */
2719     Boolean 	  undefErr; 	    /* TRUE if undefineds are an error */
2720 {
2721     Buffer  	  buf;	    	    /* Buffer for forming things */
2722     char    	  *val;		    /* Value to substitute for a variable */
2723     int	    	  length;   	    /* Length of the variable invocation */
2724     Boolean 	  doFree;   	    /* Set true if val should be freed */
2725     static Boolean errorReported;   /* Set true if an error has already
2726 				     * been reported to prevent a plethora
2727 				     * of messages when recursing */
2728 
2729     buf = Buf_Init (MAKE_BSIZE);
2730     errorReported = FALSE;
2731 
2732     while (*str) {
2733 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
2734 	    /*
2735 	     * A dollar sign may be escaped either with another dollar sign.
2736 	     * In such a case, we skip over the escape character and store the
2737 	     * dollar sign into the buffer directly.
2738 	     */
2739 	    str++;
2740 	    Buf_AddByte(buf, (Byte)*str);
2741 	    str++;
2742 	} else if (*str != '$') {
2743 	    /*
2744 	     * Skip as many characters as possible -- either to the end of
2745 	     * the string or to the next dollar sign (variable invocation).
2746 	     */
2747 	    char  *cp;
2748 
2749 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
2750 		continue;
2751 	    Buf_AddBytes(buf, str - cp, (Byte *)cp);
2752 	} else {
2753 	    if (var != NULL) {
2754 		int expand;
2755 		for (;;) {
2756 		    if (str[1] != '(' && str[1] != '{') {
2757 			if (str[1] != *var || strlen(var) > 1) {
2758 			    Buf_AddBytes(buf, 2, (Byte *) str);
2759 			    str += 2;
2760 			    expand = FALSE;
2761 			}
2762 			else
2763 			    expand = TRUE;
2764 			break;
2765 		    }
2766 		    else {
2767 			char *p;
2768 
2769 			/*
2770 			 * Scan up to the end of the variable name.
2771 			 */
2772 			for (p = &str[2]; *p &&
2773 			     *p != ':' && *p != ')' && *p != '}'; p++)
2774 			    if (*p == '$')
2775 				break;
2776 			/*
2777 			 * A variable inside the variable. We cannot expand
2778 			 * the external variable yet, so we try again with
2779 			 * the nested one
2780 			 */
2781 			if (*p == '$') {
2782 			    Buf_AddBytes(buf, p - str, (Byte *) str);
2783 			    str = p;
2784 			    continue;
2785 			}
2786 
2787 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
2788 			    var[p - str - 2] != '\0') {
2789 			    /*
2790 			     * Not the variable we want to expand, scan
2791 			     * until the next variable
2792 			     */
2793 			    for (;*p != '$' && *p != '\0'; p++)
2794 				continue;
2795 			    Buf_AddBytes(buf, p - str, (Byte *) str);
2796 			    str = p;
2797 			    expand = FALSE;
2798 			}
2799 			else
2800 			    expand = TRUE;
2801 			break;
2802 		    }
2803 		}
2804 		if (!expand)
2805 		    continue;
2806 	    }
2807 
2808 	    val = Var_Parse (str, ctxt, undefErr, &length, &doFree);
2809 
2810 	    /*
2811 	     * When we come down here, val should either point to the
2812 	     * value of this variable, suitably modified, or be NULL.
2813 	     * Length should be the total length of the potential
2814 	     * variable invocation (from $ to end character...)
2815 	     */
2816 	    if (val == var_Error || val == varNoError) {
2817 		/*
2818 		 * If performing old-time variable substitution, skip over
2819 		 * the variable and continue with the substitution. Otherwise,
2820 		 * store the dollar sign and advance str so we continue with
2821 		 * the string...
2822 		 */
2823 		if (oldVars) {
2824 		    str += length;
2825 		} else if (undefErr) {
2826 		    /*
2827 		     * If variable is undefined, complain and skip the
2828 		     * variable. The complaint will stop us from doing anything
2829 		     * when the file is parsed.
2830 		     */
2831 		    if (!errorReported) {
2832 			Parse_Error (PARSE_FATAL,
2833 				     "Undefined variable \"%.*s\"",length,str);
2834 		    }
2835 		    str += length;
2836 		    errorReported = TRUE;
2837 		} else {
2838 		    Buf_AddByte (buf, (Byte)*str);
2839 		    str += 1;
2840 		}
2841 	    } else {
2842 		/*
2843 		 * We've now got a variable structure to store in. But first,
2844 		 * advance the string pointer.
2845 		 */
2846 		str += length;
2847 
2848 		/*
2849 		 * Copy all the characters from the variable value straight
2850 		 * into the new string.
2851 		 */
2852 		Buf_AddBytes (buf, strlen (val), (Byte *)val);
2853 		if (doFree) {
2854 		    free ((Address)val);
2855 		}
2856 	    }
2857 	}
2858     }
2859 
2860     Buf_AddByte (buf, '\0');
2861     str = (char *)Buf_GetAll (buf, (int *)NULL);
2862     Buf_Destroy (buf, FALSE);
2863     return (str);
2864 }
2865 
2866 /*-
2867  *-----------------------------------------------------------------------
2868  * Var_GetTail --
2869  *	Return the tail from each of a list of words. Used to set the
2870  *	System V local variables.
2871  *
2872  * Results:
2873  *	The resulting string.
2874  *
2875  * Side Effects:
2876  *	None.
2877  *
2878  *-----------------------------------------------------------------------
2879  */
2880 #if 0
2881 char *
2882 Var_GetTail(file)
2883     char    	*file;	    /* Filename to modify */
2884 {
2885     return(VarModify(file, VarTail, (ClientData)0));
2886 }
2887 
2888 /*-
2889  *-----------------------------------------------------------------------
2890  * Var_GetHead --
2891  *	Find the leading components of a (list of) filename(s).
2892  *	XXX: VarHead does not replace foo by ., as (sun) System V make
2893  *	does.
2894  *
2895  * Results:
2896  *	The leading components.
2897  *
2898  * Side Effects:
2899  *	None.
2900  *
2901  *-----------------------------------------------------------------------
2902  */
2903 char *
2904 Var_GetHead(file)
2905     char    	*file;	    /* Filename to manipulate */
2906 {
2907     return(VarModify(file, VarHead, (ClientData)0));
2908 }
2909 #endif
2910 
2911 /*-
2912  *-----------------------------------------------------------------------
2913  * Var_Init --
2914  *	Initialize the module
2915  *
2916  * Results:
2917  *	None
2918  *
2919  * Side Effects:
2920  *	The VAR_CMD and VAR_GLOBAL contexts are created
2921  *-----------------------------------------------------------------------
2922  */
2923 void
2924 Var_Init ()
2925 {
2926     VAR_GLOBAL = Targ_NewGN ("Global");
2927     VAR_CMD = Targ_NewGN ("Command");
2928 
2929 }
2930 
2931 
2932 void
2933 Var_End ()
2934 {
2935 }
2936 
2937 
2938 /****************** PRINT DEBUGGING INFO *****************/
2939 static void
2940 VarPrintVar (vp)
2941     ClientData vp;
2942 {
2943     Var    *v = (Var *) vp;
2944     printf ("%-16s = %s\n", v->name, (char *) Buf_GetAll(v->val, (int *)NULL));
2945 }
2946 
2947 /*-
2948  *-----------------------------------------------------------------------
2949  * Var_Dump --
2950  *	print all variables in a context
2951  *-----------------------------------------------------------------------
2952  */
2953 void
2954 Var_Dump (ctxt)
2955     GNode          *ctxt;
2956 {
2957     Hash_Search search;
2958     Hash_Entry *h;
2959 
2960     for (h = Hash_EnumFirst(&ctxt->context, &search);
2961 	 h != NULL;
2962 	 h = Hash_EnumNext(&search)) {
2963 	    VarPrintVar(Hash_GetValue(h));
2964     }
2965 }
2966