xref: /netbsd-src/usr.bin/make/var.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: var.c,v 1.100 2005/08/27 08:04:26 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Adam de Boor.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 /*
36  * Copyright (c) 1989 by Berkeley Softworks
37  * All rights reserved.
38  *
39  * This code is derived from software contributed to Berkeley by
40  * Adam de Boor.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by the University of
53  *	California, Berkeley and its contributors.
54  * 4. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  */
70 
71 #ifndef MAKE_NATIVE
72 static char rcsid[] = "$NetBSD: var.c,v 1.100 2005/08/27 08:04:26 christos Exp $";
73 #else
74 #include <sys/cdefs.h>
75 #ifndef lint
76 #if 0
77 static char sccsid[] = "@(#)var.c	8.3 (Berkeley) 3/19/94";
78 #else
79 __RCSID("$NetBSD: var.c,v 1.100 2005/08/27 08:04:26 christos Exp $");
80 #endif
81 #endif /* not lint */
82 #endif
83 
84 /*-
85  * var.c --
86  *	Variable-handling functions
87  *
88  * Interface:
89  *	Var_Set	  	    Set the value of a variable in the given
90  *	    	  	    context. The variable is created if it doesn't
91  *	    	  	    yet exist. The value and variable name need not
92  *	    	  	    be preserved.
93  *
94  *	Var_Append	    Append more characters to an existing variable
95  *	    	  	    in the given context. The variable needn't
96  *	    	  	    exist already -- it will be created if it doesn't.
97  *	    	  	    A space is placed between the old value and the
98  *	    	  	    new one.
99  *
100  *	Var_Exists	    See if a variable exists.
101  *
102  *	Var_Value 	    Return the value of a variable in a context or
103  *	    	  	    NULL if the variable is undefined.
104  *
105  *	Var_Subst 	    Substitute named variable, or all variables if
106  *			    NULL in a string using
107  *	    	  	    the given context as the top-most one. If the
108  *	    	  	    third argument is non-zero, Parse_Error is
109  *	    	  	    called if any variables are undefined.
110  *
111  *	Var_Parse 	    Parse a variable expansion from a string and
112  *	    	  	    return the result and the number of characters
113  *	    	  	    consumed.
114  *
115  *	Var_Delete	    Delete a variable in a context.
116  *
117  *	Var_Init  	    Initialize this module.
118  *
119  * Debugging:
120  *	Var_Dump  	    Print out all variables defined in the given
121  *	    	  	    context.
122  *
123  * XXX: There's a lot of duplication in these functions.
124  */
125 
126 #ifndef NO_REGEX
127 #include    <sys/types.h>
128 #include    <regex.h>
129 #endif
130 #include    <ctype.h>
131 #include    <stdlib.h>
132 #include    <limits.h>
133 
134 #include    "make.h"
135 #include    "buf.h"
136 
137 /*
138  * This is a harmless return value for Var_Parse that can be used by Var_Subst
139  * to determine if there was an error in parsing -- easier than returning
140  * a flag, as things outside this module don't give a hoot.
141  */
142 char 	var_Error[] = "";
143 
144 /*
145  * Similar to var_Error, but returned when the 'err' flag for Var_Parse is
146  * set false. Why not just use a constant? Well, gcc likes to condense
147  * identical string instances...
148  */
149 static char	varNoError[] = "";
150 
151 /*
152  * Internally, variables are contained in four different contexts.
153  *	1) the environment. They may not be changed. If an environment
154  *	    variable is appended-to, the result is placed in the global
155  *	    context.
156  *	2) the global context. Variables set in the Makefile are located in
157  *	    the global context. It is the penultimate context searched when
158  *	    substituting.
159  *	3) the command-line context. All variables set on the command line
160  *	   are placed in this context. They are UNALTERABLE once placed here.
161  *	4) the local context. Each target has associated with it a context
162  *	   list. On this list are located the structures describing such
163  *	   local variables as $(@) and $(*)
164  * The four contexts are searched in the reverse order from which they are
165  * listed.
166  */
167 GNode          *VAR_GLOBAL;   /* variables from the makefile */
168 GNode          *VAR_CMD;      /* variables defined on the command-line */
169 
170 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
171 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
172 #define FIND_ENV  	0x4   /* look in the environment also */
173 
174 typedef struct Var {
175     char          *name;	/* the variable's name */
176     Buffer	  val;	    	/* its value */
177     int	    	  flags;    	/* miscellaneous status flags */
178 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
179 				     * Used to avoid recursion */
180 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
181 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
182 				     * should be destroyed when done with
183 				     * it. Used by Var_Parse for undefined,
184 				     * modified variables */
185 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
186 				     * a use for it in some modifier and
187 				     * the value is therefore valid */
188 }  Var;
189 
190 
191 /* Var*Pattern flags */
192 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
193 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
194 #define VAR_SUB_MATCHED	0x04	/* There was a match */
195 #define VAR_MATCH_START	0x08	/* Match at start of word */
196 #define VAR_MATCH_END	0x10	/* Match at end of word */
197 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
198 
199 /* Var_Set flags */
200 #define VAR_NO_EXPORT	0x01	/* do not export */
201 
202 typedef struct {
203     /*
204      * The following fields are set by Var_Parse() when it
205      * encounters modifiers that need to keep state for use by
206      * subsequent modifiers within the same variable expansion.
207      */
208     Byte	varSpace;	/* Word separator in expansions */
209     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
210 				 * single big word, even if it contains
211 				 * embedded spaces (as opposed to the
212 				 * usual behaviour of treating it as
213 				 * several space-separated words). */
214 } Var_Parse_State;
215 
216 /* struct passed as ClientData to VarSubstitute() for ":S/lhs/rhs/",
217  * to VarSYSVMatch() for ":lhs=rhs". */
218 typedef struct {
219     const char   *lhs;	    /* String to match */
220     int	    	  leftLen; /* Length of string */
221     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
222     int	    	  rightLen; /* Length of replacement */
223     int	    	  flags;
224 } VarPattern;
225 
226 /* struct passed as ClientData to VarLoopExpand() for ":@tvar@str@" */
227 typedef struct {
228     GNode	*ctxt;		/* variable context */
229     char	*tvar;		/* name of temp var */
230     int		tvarLen;
231     char	*str;		/* string to expand */
232     int		strLen;
233     int		err;		/* err for not defined */
234 } VarLoop_t;
235 
236 #ifndef NO_REGEX
237 /* struct passed as ClientData to VarRESubstitute() for ":C///" */
238 typedef struct {
239     regex_t	   re;
240     int		   nsub;
241     regmatch_t 	  *matches;
242     char 	  *replace;
243     int		   flags;
244 } VarREPattern;
245 #endif
246 
247 /* struct passed to VarSelectWords() for ":[start..end]" */
248 typedef struct {
249     int		start;		/* first word to select */
250     int		end;		/* last word to select */
251 } VarSelectWords_t;
252 
253 static Var *VarFind(const char *, GNode *, int);
254 static void VarAdd(const char *, const char *, GNode *);
255 static Boolean VarHead(GNode *, Var_Parse_State *,
256 			char *, Boolean, Buffer, ClientData);
257 static Boolean VarTail(GNode *, Var_Parse_State *,
258 			char *, Boolean, Buffer, ClientData);
259 static Boolean VarSuffix(GNode *, Var_Parse_State *,
260 			char *, Boolean, Buffer, ClientData);
261 static Boolean VarRoot(GNode *, Var_Parse_State *,
262 			char *, Boolean, Buffer, ClientData);
263 static Boolean VarMatch(GNode *, Var_Parse_State *,
264 			char *, Boolean, Buffer, ClientData);
265 #ifdef SYSVVARSUB
266 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
267 			char *, Boolean, Buffer, ClientData);
268 #endif
269 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
270 			char *, Boolean, Buffer, ClientData);
271 #ifndef NO_REGEX
272 static void VarREError(int, regex_t *, const char *);
273 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
274 			char *, Boolean, Buffer, ClientData);
275 #endif
276 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
277 			char *, Boolean, Buffer, ClientData);
278 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
279 			char *, Boolean, Buffer, ClientData);
280 static char *VarGetPattern(GNode *, Var_Parse_State *,
281 			   int, const char **, int, int *, int *,
282 			   VarPattern *);
283 static char *VarQuote(char *);
284 static char *VarChangeCase(char *, int);
285 static char *VarModify(GNode *, Var_Parse_State *,
286     const char *,
287     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer, ClientData),
288     ClientData);
289 static char *VarOrder(const char *, const char);
290 static char *VarUniq(const char *);
291 static int VarWordCompare(const void *, const void *);
292 static void VarPrintVar(ClientData);
293 
294 #define WR(a)	((char *)UNCONST(a))
295 
296 #define BROPEN	'{'
297 #define BRCLOSE	'}'
298 #define PROPEN	'('
299 #define PRCLOSE	')'
300 
301 /*-
302  *-----------------------------------------------------------------------
303  * VarFind --
304  *	Find the given variable in the given context and any other contexts
305  *	indicated.
306  *
307  * Input:
308  *	name		name to find
309  *	ctxt		context in which to find it
310  *	flags		FIND_GLOBAL set means to look in the
311  *			VAR_GLOBAL context as well. FIND_CMD set means
312  *			to look in the VAR_CMD context also. FIND_ENV
313  *			set means to look in the environment
314  *
315  * Results:
316  *	A pointer to the structure describing the desired variable or
317  *	NIL if the variable does not exist.
318  *
319  * Side Effects:
320  *	None
321  *-----------------------------------------------------------------------
322  */
323 static Var *
324 VarFind(const char *name, GNode *ctxt, int flags)
325 {
326     Hash_Entry         	*var;
327     Var		  	*v;
328 
329 	/*
330 	 * If the variable name begins with a '.', it could very well be one of
331 	 * the local ones.  We check the name against all the local variables
332 	 * and substitute the short version in for 'name' if it matches one of
333 	 * them.
334 	 */
335 	if (*name == '.' && isupper((unsigned char) name[1]))
336 		switch (name[1]) {
337 		case 'A':
338 			if (!strcmp(name, ".ALLSRC"))
339 				name = ALLSRC;
340 			if (!strcmp(name, ".ARCHIVE"))
341 				name = ARCHIVE;
342 			break;
343 		case 'I':
344 			if (!strcmp(name, ".IMPSRC"))
345 				name = IMPSRC;
346 			break;
347 		case 'M':
348 			if (!strcmp(name, ".MEMBER"))
349 				name = MEMBER;
350 			break;
351 		case 'O':
352 			if (!strcmp(name, ".OODATE"))
353 				name = OODATE;
354 			break;
355 		case 'P':
356 			if (!strcmp(name, ".PREFIX"))
357 				name = PREFIX;
358 			break;
359 		case 'T':
360 			if (!strcmp(name, ".TARGET"))
361 				name = TARGET;
362 			break;
363 		}
364     /*
365      * First look for the variable in the given context. If it's not there,
366      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
367      * depending on the FIND_* flags in 'flags'
368      */
369     var = Hash_FindEntry(&ctxt->context, name);
370 
371     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
372 	var = Hash_FindEntry(&VAR_CMD->context, name);
373     }
374     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
375 	(ctxt != VAR_GLOBAL))
376     {
377 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
378     }
379     if ((var == NULL) && (flags & FIND_ENV)) {
380 	char *env;
381 
382 	if ((env = getenv(name)) != NULL) {
383 	    int	  	len;
384 
385 	    v = emalloc(sizeof(Var));
386 	    v->name = estrdup(name);
387 
388 	    len = strlen(env);
389 
390 	    v->val = Buf_Init(len);
391 	    Buf_AddBytes(v->val, len, (Byte *)env);
392 
393 	    v->flags = VAR_FROM_ENV;
394 	    return (v);
395 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
396 		   (ctxt != VAR_GLOBAL))
397 	{
398 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
399 	    if (var == NULL) {
400 		return ((Var *)NIL);
401 	    } else {
402 		return ((Var *)Hash_GetValue(var));
403 	    }
404 	} else {
405 	    return((Var *)NIL);
406 	}
407     } else if (var == NULL) {
408 	return ((Var *)NIL);
409     } else {
410 	return ((Var *)Hash_GetValue(var));
411     }
412 }
413 
414 /*-
415  *-----------------------------------------------------------------------
416  * VarAdd  --
417  *	Add a new variable of name name and value val to the given context
418  *
419  * Input:
420  *	name		name of variable to add
421  *	val		value to set it to
422  *	ctxt		context in which to set it
423  *
424  * Results:
425  *	None
426  *
427  * Side Effects:
428  *	The new variable is placed at the front of the given context
429  *	The name and val arguments are duplicated so they may
430  *	safely be freed.
431  *-----------------------------------------------------------------------
432  */
433 static void
434 VarAdd(const char *name, const char *val, GNode *ctxt)
435 {
436     Var   	  *v;
437     int	    	  len;
438     Hash_Entry    *h;
439 
440     v = emalloc(sizeof(Var));
441 
442     len = val ? strlen(val) : 0;
443     v->val = Buf_Init(len+1);
444     Buf_AddBytes(v->val, len, (const Byte *)val);
445 
446     v->flags = 0;
447 
448     h = Hash_CreateEntry(&ctxt->context, name, NULL);
449     Hash_SetValue(h, v);
450     v->name = h->name;
451     if (DEBUG(VAR)) {
452 	printf("%s:%s = %s\n", ctxt->name, name, val);
453     }
454 }
455 
456 /*-
457  *-----------------------------------------------------------------------
458  * Var_Delete --
459  *	Remove a variable from a context.
460  *
461  * Results:
462  *	None.
463  *
464  * Side Effects:
465  *	The Var structure is removed and freed.
466  *
467  *-----------------------------------------------------------------------
468  */
469 void
470 Var_Delete(const char *name, GNode *ctxt)
471 {
472     Hash_Entry 	  *ln;
473 
474     if (DEBUG(VAR)) {
475 	printf("%s:delete %s\n", ctxt->name, name);
476     }
477     ln = Hash_FindEntry(&ctxt->context, name);
478     if (ln != NULL) {
479 	Var 	  *v;
480 
481 	v = (Var *)Hash_GetValue(ln);
482 	if (v->name != ln->name)
483 		free(v->name);
484 	Hash_DeleteEntry(&ctxt->context, ln);
485 	Buf_Destroy(v->val, TRUE);
486 	free(v);
487     }
488 }
489 
490 /*-
491  *-----------------------------------------------------------------------
492  * Var_Set --
493  *	Set the variable name to the value val in the given context.
494  *
495  * Input:
496  *	name		name of variable to set
497  *	val		value to give to the variable
498  *	ctxt		context in which to set it
499  *
500  * Results:
501  *	None.
502  *
503  * Side Effects:
504  *	If the variable doesn't yet exist, a new record is created for it.
505  *	Else the old value is freed and the new one stuck in its place
506  *
507  * Notes:
508  *	The variable is searched for only in its context before being
509  *	created in that context. I.e. if the context is VAR_GLOBAL,
510  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
511  *	VAR_CMD->context is searched. This is done to avoid the literally
512  *	thousands of unnecessary strcmp's that used to be done to
513  *	set, say, $(@) or $(<).
514  *-----------------------------------------------------------------------
515  */
516 void
517 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
518 {
519     Var   *v;
520     const char *cp = name;
521 
522     /*
523      * We only look for a variable in the given context since anything set
524      * here will override anything in a lower context, so there's not much
525      * point in searching them all just to save a bit of memory...
526      */
527     if ((name = strchr(cp, '$'))) {
528 	name = Var_Subst(NULL, cp, ctxt, 0);
529     } else
530 	name = cp;
531     v = VarFind(name, ctxt, 0);
532     if (v == (Var *)NIL) {
533 	VarAdd(name, val, ctxt);
534     } else {
535 	Buf_Discard(v->val, Buf_Size(v->val));
536 	Buf_AddBytes(v->val, strlen(val), (const Byte *)val);
537 
538 	if (DEBUG(VAR)) {
539 	    printf("%s:%s = %s\n", ctxt->name, name, val);
540 	}
541     }
542     /*
543      * Any variables given on the command line are automatically exported
544      * to the environment (as per POSIX standard)
545      */
546     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
547 
548 	/*
549 	 * If requested, don't export these in the environment
550 	 * individually.  We still put them in MAKEOVERRIDES so
551 	 * that the command-line settings continue to override
552 	 * Makefile settings.
553 	 */
554 	if (varNoExportEnv != TRUE)
555 	    setenv(name, val, 1);
556 
557 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
558     }
559     if (name != cp)
560 	free(UNCONST(name));
561 }
562 
563 /*-
564  *-----------------------------------------------------------------------
565  * Var_Append --
566  *	The variable of the given name has the given value appended to it in
567  *	the given context.
568  *
569  * Input:
570  *	name		name of variable to modify
571  *	val		String to append to it
572  *	ctxt		Context in which this should occur
573  *
574  * Results:
575  *	None
576  *
577  * Side Effects:
578  *	If the variable doesn't exist, it is created. Else the strings
579  *	are concatenated (with a space in between).
580  *
581  * Notes:
582  *	Only if the variable is being sought in the global context is the
583  *	environment searched.
584  *	XXX: Knows its calling circumstances in that if called with ctxt
585  *	an actual target, it will only search that context since only
586  *	a local variable could be being appended to. This is actually
587  *	a big win and must be tolerated.
588  *-----------------------------------------------------------------------
589  */
590 void
591 Var_Append(const char *name, const char *val, GNode *ctxt)
592 {
593     Var		   *v;
594     Hash_Entry	   *h;
595     const char *cp = name;
596 
597     if ((name = strchr(cp, '$'))) {
598 	name = Var_Subst(NULL, cp, ctxt, 0);
599     } else
600 	name = cp;
601 
602     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
603 
604     if (v == (Var *)NIL) {
605 	VarAdd(name, val, ctxt);
606     } else {
607 	Buf_AddByte(v->val, (Byte)' ');
608 	Buf_AddBytes(v->val, strlen(val), (const Byte *)val);
609 
610 	if (DEBUG(VAR)) {
611 	    printf("%s:%s = %s\n", ctxt->name, name,
612 		   (char *)Buf_GetAll(v->val, NULL));
613 	}
614 
615 	if (v->flags & VAR_FROM_ENV) {
616 	    /*
617 	     * If the original variable came from the environment, we
618 	     * have to install it in the global context (we could place
619 	     * it in the environment, but then we should provide a way to
620 	     * export other variables...)
621 	     */
622 	    v->flags &= ~VAR_FROM_ENV;
623 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
624 	    Hash_SetValue(h, v);
625 	}
626     }
627     if (name != cp)
628 	free(UNCONST(name));
629 }
630 
631 /*-
632  *-----------------------------------------------------------------------
633  * Var_Exists --
634  *	See if the given variable exists.
635  *
636  * Input:
637  *	name		Variable to find
638  *	ctxt		Context in which to start search
639  *
640  * Results:
641  *	TRUE if it does, FALSE if it doesn't
642  *
643  * Side Effects:
644  *	None.
645  *
646  *-----------------------------------------------------------------------
647  */
648 Boolean
649 Var_Exists(const char *name, GNode *ctxt)
650 {
651     Var	    	  *v;
652 
653     v = VarFind(name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
654 
655     if (v == (Var *)NIL) {
656 	return(FALSE);
657     } else if (v->flags & VAR_FROM_ENV) {
658 	free(v->name);
659 	Buf_Destroy(v->val, TRUE);
660 	free(v);
661     }
662     return(TRUE);
663 }
664 
665 /*-
666  *-----------------------------------------------------------------------
667  * Var_Value --
668  *	Return the value of the named variable in the given context
669  *
670  * Input:
671  *	name		name to find
672  *	ctxt		context in which to search for it
673  *
674  * Results:
675  *	The value if the variable exists, NULL if it doesn't
676  *
677  * Side Effects:
678  *	None
679  *-----------------------------------------------------------------------
680  */
681 char *
682 Var_Value(const char *name, GNode *ctxt, char **frp)
683 {
684     Var            *v;
685 
686     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
687     *frp = NULL;
688     if (v != (Var *)NIL) {
689 	char *p = ((char *)Buf_GetAll(v->val, NULL));
690 	if (v->flags & VAR_FROM_ENV) {
691 	    free(v->name);
692 	    Buf_Destroy(v->val, FALSE);
693 	    free(v);
694 	    *frp = p;
695 	}
696 	return p;
697     } else {
698 	return (NULL);
699     }
700 }
701 
702 /*-
703  *-----------------------------------------------------------------------
704  * VarHead --
705  *	Remove the tail of the given word and place the result in the given
706  *	buffer.
707  *
708  * Input:
709  *	word		Word to trim
710  *	addSpace	True if need to add a space to the buffer
711  *			before sticking in the head
712  *	buf		Buffer in which to store it
713  *
714  * Results:
715  *	TRUE if characters were added to the buffer (a space needs to be
716  *	added to the buffer before the next word).
717  *
718  * Side Effects:
719  *	The trimmed word is added to the buffer.
720  *
721  *-----------------------------------------------------------------------
722  */
723 static Boolean
724 VarHead(GNode *ctx __unused, Var_Parse_State *vpstate,
725 	char *word, Boolean addSpace, Buffer buf,
726 	ClientData dummy)
727 {
728     char *slash;
729 
730     slash = strrchr(word, '/');
731     if (slash != NULL) {
732 	if (addSpace && vpstate->varSpace) {
733 	    Buf_AddByte(buf, vpstate->varSpace);
734 	}
735 	*slash = '\0';
736 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
737 	*slash = '/';
738 	return (TRUE);
739     } else {
740 	/*
741 	 * If no directory part, give . (q.v. the POSIX standard)
742 	 */
743 	if (addSpace && vpstate->varSpace)
744 	    Buf_AddByte(buf, vpstate->varSpace);
745 	Buf_AddByte(buf, (Byte)'.');
746     }
747     return(dummy ? TRUE : TRUE);
748 }
749 
750 /*-
751  *-----------------------------------------------------------------------
752  * VarTail --
753  *	Remove the head of the given word and place the result in the given
754  *	buffer.
755  *
756  * Input:
757  *	word		Word to trim
758  *	addSpace	True if need to add a space to the buffer
759  *			before adding the tail
760  *	buf		Buffer in which to store it
761  *
762  * Results:
763  *	TRUE if characters were added to the buffer (a space needs to be
764  *	added to the buffer before the next word).
765  *
766  * Side Effects:
767  *	The trimmed word is added to the buffer.
768  *
769  *-----------------------------------------------------------------------
770  */
771 static Boolean
772 VarTail(GNode *ctx __unused, Var_Parse_State *vpstate,
773 	char *word, Boolean addSpace, Buffer buf,
774 	ClientData dummy)
775 {
776     char *slash;
777 
778     if (addSpace && vpstate->varSpace) {
779 	Buf_AddByte(buf, vpstate->varSpace);
780     }
781 
782     slash = strrchr(word, '/');
783     if (slash != NULL) {
784 	*slash++ = '\0';
785 	Buf_AddBytes(buf, strlen(slash), (Byte *)slash);
786 	slash[-1] = '/';
787     } else {
788 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
789     }
790     return (dummy ? TRUE : TRUE);
791 }
792 
793 /*-
794  *-----------------------------------------------------------------------
795  * VarSuffix --
796  *	Place the suffix of the given word in the given buffer.
797  *
798  * Input:
799  *	word		Word to trim
800  *	addSpace	TRUE if need to add a space before placing the
801  *			suffix in the buffer
802  *	buf		Buffer in which to store it
803  *
804  * Results:
805  *	TRUE if characters were added to the buffer (a space needs to be
806  *	added to the buffer before the next word).
807  *
808  * Side Effects:
809  *	The suffix from the word is placed in the buffer.
810  *
811  *-----------------------------------------------------------------------
812  */
813 static Boolean
814 VarSuffix(GNode *ctx __unused, Var_Parse_State *vpstate,
815 	  char *word, Boolean addSpace, Buffer buf,
816 	  ClientData dummy)
817 {
818     char *dot;
819 
820     dot = strrchr(word, '.');
821     if (dot != NULL) {
822 	if (addSpace && vpstate->varSpace) {
823 	    Buf_AddByte(buf, vpstate->varSpace);
824 	}
825 	*dot++ = '\0';
826 	Buf_AddBytes(buf, strlen(dot), (Byte *)dot);
827 	dot[-1] = '.';
828 	addSpace = TRUE;
829     }
830     return (dummy ? addSpace : addSpace);
831 }
832 
833 /*-
834  *-----------------------------------------------------------------------
835  * VarRoot --
836  *	Remove the suffix of the given word and place the result in the
837  *	buffer.
838  *
839  * Input:
840  *	word		Word to trim
841  *	addSpace	TRUE if need to add a space to the buffer
842  *			before placing the root in it
843  *	buf		Buffer in which to store it
844  *
845  * Results:
846  *	TRUE if characters were added to the buffer (a space needs to be
847  *	added to the buffer before the next word).
848  *
849  * Side Effects:
850  *	The trimmed word is added to the buffer.
851  *
852  *-----------------------------------------------------------------------
853  */
854 static Boolean
855 VarRoot(GNode *ctx __unused, Var_Parse_State *vpstate,
856 	char *word, Boolean addSpace, Buffer buf,
857 	ClientData dummy)
858 {
859     char *dot;
860 
861     if (addSpace && vpstate->varSpace) {
862 	Buf_AddByte(buf, vpstate->varSpace);
863     }
864 
865     dot = strrchr(word, '.');
866     if (dot != NULL) {
867 	*dot = '\0';
868 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
869 	*dot = '.';
870     } else {
871 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
872     }
873     return (dummy ? TRUE : TRUE);
874 }
875 
876 /*-
877  *-----------------------------------------------------------------------
878  * VarMatch --
879  *	Place the word in the buffer if it matches the given pattern.
880  *	Callback function for VarModify to implement the :M modifier.
881  *
882  * Input:
883  *	word		Word to examine
884  *	addSpace	TRUE if need to add a space to the buffer
885  *			before adding the word, if it matches
886  *	buf		Buffer in which to store it
887  *	pattern		Pattern the word must match
888  *
889  * Results:
890  *	TRUE if a space should be placed in the buffer before the next
891  *	word.
892  *
893  * Side Effects:
894  *	The word may be copied to the buffer.
895  *
896  *-----------------------------------------------------------------------
897  */
898 static Boolean
899 VarMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
900 	 char *word, Boolean addSpace, Buffer buf,
901 	 ClientData pattern)
902 {
903     if (Str_Match(word, (char *)pattern)) {
904 	if (addSpace && vpstate->varSpace) {
905 	    Buf_AddByte(buf, vpstate->varSpace);
906 	}
907 	addSpace = TRUE;
908 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
909     }
910     return(addSpace);
911 }
912 
913 #ifdef SYSVVARSUB
914 /*-
915  *-----------------------------------------------------------------------
916  * VarSYSVMatch --
917  *	Place the word in the buffer if it matches the given pattern.
918  *	Callback function for VarModify to implement the System V %
919  *	modifiers.
920  *
921  * Input:
922  *	word		Word to examine
923  *	addSpace	TRUE if need to add a space to the buffer
924  *			before adding the word, if it matches
925  *	buf		Buffer in which to store it
926  *	patp		Pattern the word must match
927  *
928  * Results:
929  *	TRUE if a space should be placed in the buffer before the next
930  *	word.
931  *
932  * Side Effects:
933  *	The word may be copied to the buffer.
934  *
935  *-----------------------------------------------------------------------
936  */
937 static Boolean
938 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
939 	     char *word, Boolean addSpace, Buffer buf,
940 	     ClientData patp)
941 {
942     int len;
943     char *ptr;
944     VarPattern 	  *pat = (VarPattern *)patp;
945     char *varexp;
946 
947     if (addSpace && vpstate->varSpace)
948 	Buf_AddByte(buf, vpstate->varSpace);
949 
950     addSpace = TRUE;
951 
952     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
953         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
954 	Str_SYSVSubst(buf, varexp, ptr, len);
955 	free(varexp);
956     } else {
957 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
958     }
959 
960     return(addSpace);
961 }
962 #endif
963 
964 
965 /*-
966  *-----------------------------------------------------------------------
967  * VarNoMatch --
968  *	Place the word in the buffer if it doesn't match the given pattern.
969  *	Callback function for VarModify to implement the :N modifier.
970  *
971  * Input:
972  *	word		Word to examine
973  *	addSpace	TRUE if need to add a space to the buffer
974  *			before adding the word, if it matches
975  *	buf		Buffer in which to store it
976  *	pattern		Pattern the word must match
977  *
978  * Results:
979  *	TRUE if a space should be placed in the buffer before the next
980  *	word.
981  *
982  * Side Effects:
983  *	The word may be copied to the buffer.
984  *
985  *-----------------------------------------------------------------------
986  */
987 static Boolean
988 VarNoMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
989 	   char *word, Boolean addSpace, Buffer buf,
990 	   ClientData pattern)
991 {
992     if (!Str_Match(word, (char *)pattern)) {
993 	if (addSpace && vpstate->varSpace) {
994 	    Buf_AddByte(buf, vpstate->varSpace);
995 	}
996 	addSpace = TRUE;
997 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
998     }
999     return(addSpace);
1000 }
1001 
1002 
1003 /*-
1004  *-----------------------------------------------------------------------
1005  * VarSubstitute --
1006  *	Perform a string-substitution on the given word, placing the
1007  *	result in the passed buffer.
1008  *
1009  * Input:
1010  *	word		Word to modify
1011  *	addSpace	True if space should be added before
1012  *			other characters
1013  *	buf		Buffer for result
1014  *	patternp	Pattern for substitution
1015  *
1016  * Results:
1017  *	TRUE if a space is needed before more characters are added.
1018  *
1019  * Side Effects:
1020  *	None.
1021  *
1022  *-----------------------------------------------------------------------
1023  */
1024 static Boolean
1025 VarSubstitute(GNode *ctx __unused, Var_Parse_State *vpstate,
1026 	      char *word, Boolean addSpace, Buffer buf,
1027 	      ClientData patternp)
1028 {
1029     int  	wordLen;    /* Length of word */
1030     char 	*cp;	    /* General pointer */
1031     VarPattern	*pattern = (VarPattern *)patternp;
1032 
1033     wordLen = strlen(word);
1034     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
1035 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
1036 	/*
1037 	 * Still substituting -- break it down into simple anchored cases
1038 	 * and if none of them fits, perform the general substitution case.
1039 	 */
1040 	if ((pattern->flags & VAR_MATCH_START) &&
1041 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
1042 		/*
1043 		 * Anchored at start and beginning of word matches pattern
1044 		 */
1045 		if ((pattern->flags & VAR_MATCH_END) &&
1046 		    (wordLen == pattern->leftLen)) {
1047 			/*
1048 			 * Also anchored at end and matches to the end (word
1049 			 * is same length as pattern) add space and rhs only
1050 			 * if rhs is non-null.
1051 			 */
1052 			if (pattern->rightLen != 0) {
1053 			    if (addSpace && vpstate->varSpace) {
1054 				Buf_AddByte(buf, vpstate->varSpace);
1055 			    }
1056 			    addSpace = TRUE;
1057 			    Buf_AddBytes(buf, pattern->rightLen,
1058 					 (const Byte *)pattern->rhs);
1059 			}
1060 			pattern->flags |= VAR_SUB_MATCHED;
1061 		} else if (pattern->flags & VAR_MATCH_END) {
1062 		    /*
1063 		     * Doesn't match to end -- copy word wholesale
1064 		     */
1065 		    goto nosub;
1066 		} else {
1067 		    /*
1068 		     * Matches at start but need to copy in trailing characters
1069 		     */
1070 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
1071 			if (addSpace && vpstate->varSpace) {
1072 			    Buf_AddByte(buf, vpstate->varSpace);
1073 			}
1074 			addSpace = TRUE;
1075 		    }
1076 		    Buf_AddBytes(buf, pattern->rightLen,
1077 			(const Byte *)pattern->rhs);
1078 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
1079 				 (Byte *)(word + pattern->leftLen));
1080 		    pattern->flags |= VAR_SUB_MATCHED;
1081 		}
1082 	} else if (pattern->flags & VAR_MATCH_START) {
1083 	    /*
1084 	     * Had to match at start of word and didn't -- copy whole word.
1085 	     */
1086 	    goto nosub;
1087 	} else if (pattern->flags & VAR_MATCH_END) {
1088 	    /*
1089 	     * Anchored at end, Find only place match could occur (leftLen
1090 	     * characters from the end of the word) and see if it does. Note
1091 	     * that because the $ will be left at the end of the lhs, we have
1092 	     * to use strncmp.
1093 	     */
1094 	    cp = word + (wordLen - pattern->leftLen);
1095 	    if ((cp >= word) &&
1096 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
1097 		/*
1098 		 * Match found. If we will place characters in the buffer,
1099 		 * add a space before hand as indicated by addSpace, then
1100 		 * stuff in the initial, unmatched part of the word followed
1101 		 * by the right-hand-side.
1102 		 */
1103 		if (((cp - word) + pattern->rightLen) != 0) {
1104 		    if (addSpace && vpstate->varSpace) {
1105 			Buf_AddByte(buf, vpstate->varSpace);
1106 		    }
1107 		    addSpace = TRUE;
1108 		}
1109 		Buf_AddBytes(buf, cp - word, (const Byte *)word);
1110 		Buf_AddBytes(buf, pattern->rightLen,
1111 		    (const Byte *)pattern->rhs);
1112 		pattern->flags |= VAR_SUB_MATCHED;
1113 	    } else {
1114 		/*
1115 		 * Had to match at end and didn't. Copy entire word.
1116 		 */
1117 		goto nosub;
1118 	    }
1119 	} else {
1120 	    /*
1121 	     * Pattern is unanchored: search for the pattern in the word using
1122 	     * String_FindSubstring, copying unmatched portions and the
1123 	     * right-hand-side for each match found, handling non-global
1124 	     * substitutions correctly, etc. When the loop is done, any
1125 	     * remaining part of the word (word and wordLen are adjusted
1126 	     * accordingly through the loop) is copied straight into the
1127 	     * buffer.
1128 	     * addSpace is set FALSE as soon as a space is added to the
1129 	     * buffer.
1130 	     */
1131 	    Boolean done;
1132 	    int origSize;
1133 
1134 	    done = FALSE;
1135 	    origSize = Buf_Size(buf);
1136 	    while (!done) {
1137 		cp = Str_FindSubstring(word, pattern->lhs);
1138 		if (cp != NULL) {
1139 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
1140 			Buf_AddByte(buf, vpstate->varSpace);
1141 			addSpace = FALSE;
1142 		    }
1143 		    Buf_AddBytes(buf, cp-word, (const Byte *)word);
1144 		    Buf_AddBytes(buf, pattern->rightLen,
1145 			(const Byte *)pattern->rhs);
1146 		    wordLen -= (cp - word) + pattern->leftLen;
1147 		    word = cp + pattern->leftLen;
1148 		    if (wordLen == 0) {
1149 			done = TRUE;
1150 		    }
1151 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
1152 			done = TRUE;
1153 		    }
1154 		    pattern->flags |= VAR_SUB_MATCHED;
1155 		} else {
1156 		    done = TRUE;
1157 		}
1158 	    }
1159 	    if (wordLen != 0) {
1160 		if (addSpace && vpstate->varSpace) {
1161 		    Buf_AddByte(buf, vpstate->varSpace);
1162 		}
1163 		Buf_AddBytes(buf, wordLen, (Byte *)word);
1164 	    }
1165 	    /*
1166 	     * If added characters to the buffer, need to add a space
1167 	     * before we add any more. If we didn't add any, just return
1168 	     * the previous value of addSpace.
1169 	     */
1170 	    return ((Buf_Size(buf) != origSize) || addSpace);
1171 	}
1172 	return (addSpace);
1173     }
1174  nosub:
1175     if (addSpace && vpstate->varSpace) {
1176 	Buf_AddByte(buf, vpstate->varSpace);
1177     }
1178     Buf_AddBytes(buf, wordLen, (Byte *)word);
1179     return(TRUE);
1180 }
1181 
1182 #ifndef NO_REGEX
1183 /*-
1184  *-----------------------------------------------------------------------
1185  * VarREError --
1186  *	Print the error caused by a regcomp or regexec call.
1187  *
1188  * Results:
1189  *	None.
1190  *
1191  * Side Effects:
1192  *	An error gets printed.
1193  *
1194  *-----------------------------------------------------------------------
1195  */
1196 static void
1197 VarREError(int err, regex_t *pat, const char *str)
1198 {
1199     char *errbuf;
1200     int errlen;
1201 
1202     errlen = regerror(err, pat, 0, 0);
1203     errbuf = emalloc(errlen);
1204     regerror(err, pat, errbuf, errlen);
1205     Error("%s: %s", str, errbuf);
1206     free(errbuf);
1207 }
1208 
1209 
1210 /*-
1211  *-----------------------------------------------------------------------
1212  * VarRESubstitute --
1213  *	Perform a regex substitution on the given word, placing the
1214  *	result in the passed buffer.
1215  *
1216  * Results:
1217  *	TRUE if a space is needed before more characters are added.
1218  *
1219  * Side Effects:
1220  *	None.
1221  *
1222  *-----------------------------------------------------------------------
1223  */
1224 static Boolean
1225 VarRESubstitute(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
1226 		char *word, Boolean addSpace, Buffer buf,
1227 		ClientData patternp)
1228 {
1229     VarREPattern *pat;
1230     int xrv;
1231     char *wp;
1232     char *rp;
1233     int added;
1234     int flags = 0;
1235 
1236 #define MAYBE_ADD_SPACE()		\
1237 	if (addSpace && !added)		\
1238 	    Buf_AddByte(buf, ' ');	\
1239 	added = 1
1240 
1241     added = 0;
1242     wp = word;
1243     pat = patternp;
1244 
1245     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1246 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1247 	xrv = REG_NOMATCH;
1248     else {
1249     tryagain:
1250 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1251     }
1252 
1253     switch (xrv) {
1254     case 0:
1255 	pat->flags |= VAR_SUB_MATCHED;
1256 	if (pat->matches[0].rm_so > 0) {
1257 	    MAYBE_ADD_SPACE();
1258 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1259 	}
1260 
1261 	for (rp = pat->replace; *rp; rp++) {
1262 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1263 		MAYBE_ADD_SPACE();
1264 		Buf_AddByte(buf,rp[1]);
1265 		rp++;
1266 	    }
1267 	    else if ((*rp == '&') ||
1268 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1269 		int n;
1270 		const char *subbuf;
1271 		int sublen;
1272 		char errstr[3];
1273 
1274 		if (*rp == '&') {
1275 		    n = 0;
1276 		    errstr[0] = '&';
1277 		    errstr[1] = '\0';
1278 		} else {
1279 		    n = rp[1] - '0';
1280 		    errstr[0] = '\\';
1281 		    errstr[1] = rp[1];
1282 		    errstr[2] = '\0';
1283 		    rp++;
1284 		}
1285 
1286 		if (n > pat->nsub) {
1287 		    Error("No subexpression %s", &errstr[0]);
1288 		    subbuf = "";
1289 		    sublen = 0;
1290 		} else if ((pat->matches[n].rm_so == -1) &&
1291 			   (pat->matches[n].rm_eo == -1)) {
1292 		    Error("No match for subexpression %s", &errstr[0]);
1293 		    subbuf = "";
1294 		    sublen = 0;
1295 	        } else {
1296 		    subbuf = wp + pat->matches[n].rm_so;
1297 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1298 		}
1299 
1300 		if (sublen > 0) {
1301 		    MAYBE_ADD_SPACE();
1302 		    Buf_AddBytes(buf, sublen, subbuf);
1303 		}
1304 	    } else {
1305 		MAYBE_ADD_SPACE();
1306 		Buf_AddByte(buf, *rp);
1307 	    }
1308 	}
1309 	wp += pat->matches[0].rm_eo;
1310 	if (pat->flags & VAR_SUB_GLOBAL) {
1311 	    flags |= REG_NOTBOL;
1312 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1313 		MAYBE_ADD_SPACE();
1314 		Buf_AddByte(buf, *wp);
1315 		wp++;
1316 
1317 	    }
1318 	    if (*wp)
1319 		goto tryagain;
1320 	}
1321 	if (*wp) {
1322 	    MAYBE_ADD_SPACE();
1323 	    Buf_AddBytes(buf, strlen(wp), wp);
1324 	}
1325 	break;
1326     default:
1327 	VarREError(xrv, &pat->re, "Unexpected regex error");
1328        /* fall through */
1329     case REG_NOMATCH:
1330 	if (*wp) {
1331 	    MAYBE_ADD_SPACE();
1332 	    Buf_AddBytes(buf,strlen(wp),wp);
1333 	}
1334 	break;
1335     }
1336     return(addSpace||added);
1337 }
1338 #endif
1339 
1340 
1341 
1342 /*-
1343  *-----------------------------------------------------------------------
1344  * VarLoopExpand --
1345  *	Implements the :@<temp>@<string>@ modifier of ODE make.
1346  *	We set the temp variable named in pattern.lhs to word and expand
1347  *	pattern.rhs storing the result in the passed buffer.
1348  *
1349  * Input:
1350  *	word		Word to modify
1351  *	addSpace	True if space should be added before
1352  *			other characters
1353  *	buf		Buffer for result
1354  *	pattern		Datafor substitution
1355  *
1356  * Results:
1357  *	TRUE if a space is needed before more characters are added.
1358  *
1359  * Side Effects:
1360  *	None.
1361  *
1362  *-----------------------------------------------------------------------
1363  */
1364 static Boolean
1365 VarLoopExpand(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
1366 	      char *word, Boolean addSpace, Buffer buf,
1367 	      ClientData loopp)
1368 {
1369     VarLoop_t	*loop = (VarLoop_t *)loopp;
1370     char *s;
1371     int slen;
1372 
1373     if (word && *word) {
1374         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
1375         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->err);
1376         if (s != NULL && *s != '\0') {
1377             if (addSpace && *s != '\n')
1378                 Buf_AddByte(buf, ' ');
1379             Buf_AddBytes(buf, (slen = strlen(s)), (Byte *)s);
1380             addSpace = (slen > 0 && s[slen - 1] != '\n');
1381             free(s);
1382         }
1383     }
1384     return addSpace;
1385 }
1386 
1387 
1388 /*-
1389  *-----------------------------------------------------------------------
1390  * VarSelectWords --
1391  *	Implements the :[start..end] modifier.
1392  *	This is a special case of VarModify since we want to be able
1393  *	to scan the list backwards if start > end.
1394  *
1395  * Input:
1396  *	str		String whose words should be trimmed
1397  *	seldata		words to select
1398  *
1399  * Results:
1400  *	A string of all the words selected.
1401  *
1402  * Side Effects:
1403  *	None.
1404  *
1405  *-----------------------------------------------------------------------
1406  */
1407 static char *
1408 VarSelectWords(GNode *ctx __unused, Var_Parse_State *vpstate,
1409 	       const char *str, VarSelectWords_t *seldata)
1410 {
1411     Buffer  	  buf;	    	    /* Buffer for the new string */
1412     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1413 				     * buffer before adding the trimmed
1414 				     * word */
1415     char **av;			    /* word list */
1416     char *as;			    /* word list memory */
1417     int ac, i;
1418     int start, end, step;
1419 
1420     buf = Buf_Init(0);
1421     addSpace = FALSE;
1422 
1423     if (vpstate->oneBigWord) {
1424 	/* fake what brk_string() would do if there were only one word */
1425 	ac = 1;
1426     	av = emalloc((ac + 1) * sizeof(char *));
1427 	as = strdup(str);
1428 	av[0] = as;
1429 	av[1] = NULL;
1430     } else {
1431 	av = brk_string(str, &ac, FALSE, &as);
1432     }
1433 
1434     /*
1435      * Now sanitize seldata.
1436      * If seldata->start or seldata->end are negative, convert them to
1437      * the positive equivalents (-1 gets converted to argc, -2 gets
1438      * converted to (argc-1), etc.).
1439      */
1440     if (seldata->start < 0)
1441 	seldata->start = ac + seldata->start + 1;
1442     if (seldata->end < 0)
1443 	seldata->end = ac + seldata->end + 1;
1444 
1445     /*
1446      * We avoid scanning more of the list than we need to.
1447      */
1448     if (seldata->start > seldata->end) {
1449 	start = MIN(ac, seldata->start) - 1;
1450 	end = MAX(0, seldata->end - 1);
1451 	step = -1;
1452     } else {
1453 	start = MAX(0, seldata->start - 1);
1454 	end = MIN(ac, seldata->end);
1455 	step = 1;
1456     }
1457 
1458     for (i = start;
1459 	 (step < 0 && i >= end) || (step > 0 && i < end);
1460 	 i += step) {
1461 	if (av[i] && *av[i]) {
1462 	    if (addSpace && vpstate->varSpace) {
1463 		Buf_AddByte(buf, vpstate->varSpace);
1464 	    }
1465 	    Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1466 	    addSpace = TRUE;
1467 	}
1468     }
1469 
1470     free(as);
1471     free(av);
1472 
1473     Buf_AddByte(buf, '\0');
1474     as = (char *)Buf_GetAll(buf, NULL);
1475     Buf_Destroy(buf, FALSE);
1476     return (as);
1477 }
1478 
1479 /*-
1480  *-----------------------------------------------------------------------
1481  * VarModify --
1482  *	Modify each of the words of the passed string using the given
1483  *	function. Used to implement all modifiers.
1484  *
1485  * Input:
1486  *	str		String whose words should be trimmed
1487  *	modProc		Function to use to modify them
1488  *	datum		Datum to pass it
1489  *
1490  * Results:
1491  *	A string of all the words modified appropriately.
1492  *
1493  * Side Effects:
1494  *	None.
1495  *
1496  *-----------------------------------------------------------------------
1497  */
1498 static char *
1499 VarModify(GNode *ctx, Var_Parse_State *vpstate,
1500     const char *str,
1501     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
1502 		       Boolean, Buffer, ClientData),
1503     ClientData datum)
1504 {
1505     Buffer  	  buf;	    	    /* Buffer for the new string */
1506     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1507 				     * buffer before adding the trimmed
1508 				     * word */
1509     char **av;			    /* word list */
1510     char *as;			    /* word list memory */
1511     int ac, i;
1512 
1513     buf = Buf_Init(0);
1514     addSpace = FALSE;
1515 
1516     if (vpstate->oneBigWord) {
1517 	/* fake what brk_string() would do if there were only one word */
1518 	ac = 1;
1519     	av = emalloc((ac + 1) * sizeof(char *));
1520 	as = strdup(str);
1521 	av[0] = as;
1522 	av[1] = NULL;
1523     } else {
1524 	av = brk_string(str, &ac, FALSE, &as);
1525     }
1526 
1527     for (i = 0; i < ac; i++) {
1528 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, buf, datum);
1529     }
1530 
1531     free(as);
1532     free(av);
1533 
1534     Buf_AddByte(buf, '\0');
1535     as = (char *)Buf_GetAll(buf, NULL);
1536     Buf_Destroy(buf, FALSE);
1537     return (as);
1538 }
1539 
1540 
1541 static int
1542 VarWordCompare(const void *a, const void *b)
1543 {
1544 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
1545 	return r;
1546 }
1547 
1548 /*-
1549  *-----------------------------------------------------------------------
1550  * VarOrder --
1551  *	Order the words in the string.
1552  *
1553  * Input:
1554  *	str		String whose words should be sorted.
1555  *	otype		How to order: s - sort, x - random.
1556  *
1557  * Results:
1558  *	A string containing the words ordered.
1559  *
1560  * Side Effects:
1561  *	None.
1562  *
1563  *-----------------------------------------------------------------------
1564  */
1565 static char *
1566 VarOrder(const char *str, const char otype)
1567 {
1568     Buffer  	  buf;	    	    /* Buffer for the new string */
1569     char **av;			    /* word list [first word does not count] */
1570     char *as;			    /* word list memory */
1571     int ac, i;
1572 
1573     buf = Buf_Init(0);
1574 
1575     av = brk_string(str, &ac, FALSE, &as);
1576 
1577     if (ac > 0)
1578 	switch (otype) {
1579 	case 's':	/* sort alphabetically */
1580 	    qsort(av, ac, sizeof(char *), VarWordCompare);
1581 	    break;
1582 	case 'x':	/* randomize */
1583 	{
1584 	    int rndidx;
1585 	    char *t;
1586 
1587 	    /*
1588 	     * We will use [ac..2] range for mod factors. This will produce
1589 	     * random numbers in [(ac-1)..0] interval, and minimal
1590 	     * reasonable value for mod factor is 2 (the mod 1 will produce
1591 	     * 0 with probability 1).
1592 	     */
1593 	    for (i = ac-1; i > 0; i--) {
1594 		rndidx = random() % (i + 1);
1595 		if (i != rndidx) {
1596 		    t = av[i];
1597 		    av[i] = av[rndidx];
1598 		    av[rndidx] = t;
1599 		}
1600 	    }
1601 	}
1602 	} /* end of switch */
1603 
1604     for (i = 0; i < ac; i++) {
1605 	Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1606 	if (i != ac - 1)
1607 	    Buf_AddByte(buf, ' ');
1608     }
1609 
1610     free(as);
1611     free(av);
1612 
1613     Buf_AddByte(buf, '\0');
1614     as = (char *)Buf_GetAll(buf, NULL);
1615     Buf_Destroy(buf, FALSE);
1616     return (as);
1617 }
1618 
1619 
1620 /*-
1621  *-----------------------------------------------------------------------
1622  * VarUniq --
1623  *	Remove adjacent duplicate words.
1624  *
1625  * Input:
1626  *	str		String whose words should be sorted
1627  *
1628  * Results:
1629  *	A string containing the resulting words.
1630  *
1631  * Side Effects:
1632  *	None.
1633  *
1634  *-----------------------------------------------------------------------
1635  */
1636 static char *
1637 VarUniq(const char *str)
1638 {
1639     Buffer	  buf;	    	    /* Buffer for new string */
1640     char 	**av;		    /* List of words to affect */
1641     char 	 *as;		    /* Word list memory */
1642     int 	  ac, i, j;
1643 
1644     buf = Buf_Init(0);
1645     av = brk_string(str, &ac, FALSE, &as);
1646 
1647     if (ac > 1) {
1648 	for (j = 0, i = 1; i < ac; i++)
1649 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
1650 		av[j] = av[i];
1651 	ac = j + 1;
1652     }
1653 
1654     for (i = 0; i < ac; i++) {
1655 	Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1656 	if (i != ac - 1)
1657 	    Buf_AddByte(buf, ' ');
1658     }
1659 
1660     free(as);
1661     free(av);
1662 
1663     Buf_AddByte(buf, '\0');
1664     as = (char *)Buf_GetAll(buf, NULL);
1665     Buf_Destroy(buf, FALSE);
1666     return as;
1667 }
1668 
1669 
1670 /*-
1671  *-----------------------------------------------------------------------
1672  * VarGetPattern --
1673  *	Pass through the tstr looking for 1) escaped delimiters,
1674  *	'$'s and backslashes (place the escaped character in
1675  *	uninterpreted) and 2) unescaped $'s that aren't before
1676  *	the delimiter (expand the variable substitution unless flags
1677  *	has VAR_NOSUBST set).
1678  *	Return the expanded string or NULL if the delimiter was missing
1679  *	If pattern is specified, handle escaped ampersands, and replace
1680  *	unescaped ampersands with the lhs of the pattern.
1681  *
1682  * Results:
1683  *	A string of all the words modified appropriately.
1684  *	If length is specified, return the string length of the buffer
1685  *	If flags is specified and the last character of the pattern is a
1686  *	$ set the VAR_MATCH_END bit of flags.
1687  *
1688  * Side Effects:
1689  *	None.
1690  *-----------------------------------------------------------------------
1691  */
1692 static char *
1693 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate __unused,
1694 	      int err, const char **tstr, int delim, int *flags,
1695 	      int *length, VarPattern *pattern)
1696 {
1697     const char *cp;
1698     Buffer buf = Buf_Init(0);
1699     int junk;
1700     if (length == NULL)
1701 	length = &junk;
1702 
1703 #define IS_A_MATCH(cp, delim) \
1704     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
1705      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
1706 
1707     /*
1708      * Skim through until the matching delimiter is found;
1709      * pick up variable substitutions on the way. Also allow
1710      * backslashes to quote the delimiter, $, and \, but don't
1711      * touch other backslashes.
1712      */
1713     for (cp = *tstr; *cp && (*cp != delim); cp++) {
1714 	if (IS_A_MATCH(cp, delim)) {
1715 	    Buf_AddByte(buf, (Byte)cp[1]);
1716 	    cp++;
1717 	} else if (*cp == '$') {
1718 	    if (cp[1] == delim) {
1719 		if (flags == NULL)
1720 		    Buf_AddByte(buf, (Byte)*cp);
1721 		else
1722 		    /*
1723 		     * Unescaped $ at end of pattern => anchor
1724 		     * pattern at end.
1725 		     */
1726 		    *flags |= VAR_MATCH_END;
1727 	    } else {
1728 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
1729 		    char   *cp2;
1730 		    int     len;
1731 		    Boolean freeIt;
1732 
1733 		    /*
1734 		     * If unescaped dollar sign not before the
1735 		     * delimiter, assume it's a variable
1736 		     * substitution and recurse.
1737 		     */
1738 		    cp2 = Var_Parse(cp, ctxt, err, &len, &freeIt);
1739 		    Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
1740 		    if (freeIt)
1741 			free(cp2);
1742 		    cp += len - 1;
1743 		} else {
1744 		    const char *cp2 = &cp[1];
1745 
1746 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
1747 			/*
1748 			 * Find the end of this variable reference
1749 			 * and suck it in without further ado.
1750 			 * It will be interperated later.
1751 			 */
1752 			int have = *cp2;
1753 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
1754 			int depth = 1;
1755 
1756 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
1757 			    if (cp2[-1] != '\\') {
1758 				if (*cp2 == have)
1759 				    ++depth;
1760 				if (*cp2 == want)
1761 				    --depth;
1762 			    }
1763 			}
1764 			Buf_AddBytes(buf, cp2 - cp, (const Byte *)cp);
1765 			cp = --cp2;
1766 		    } else
1767 			Buf_AddByte(buf, (Byte)*cp);
1768 		}
1769 	    }
1770 	}
1771 	else if (pattern && *cp == '&')
1772 	    Buf_AddBytes(buf, pattern->leftLen, (const Byte *)pattern->lhs);
1773 	else
1774 	    Buf_AddByte(buf, (Byte)*cp);
1775     }
1776 
1777     Buf_AddByte(buf, (Byte)'\0');
1778 
1779     if (*cp != delim) {
1780 	*tstr = cp;
1781 	*length = 0;
1782 	return NULL;
1783     }
1784     else {
1785 	char *rstr;
1786 	*tstr = ++cp;
1787 	rstr = (char *)Buf_GetAll(buf, length);
1788 	*length -= 1;	/* Don't count the NULL */
1789 	Buf_Destroy(buf, FALSE);
1790 	return rstr;
1791     }
1792 }
1793 
1794 /*-
1795  *-----------------------------------------------------------------------
1796  * VarQuote --
1797  *	Quote shell meta-characters in the string
1798  *
1799  * Results:
1800  *	The quoted string
1801  *
1802  * Side Effects:
1803  *	None.
1804  *
1805  *-----------------------------------------------------------------------
1806  */
1807 static char *
1808 VarQuote(char *str)
1809 {
1810 
1811     Buffer  	  buf;
1812     /* This should cover most shells :-( */
1813     static char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
1814 
1815     buf = Buf_Init(MAKE_BSIZE);
1816     for (; *str; str++) {
1817 	if (strchr(meta, *str) != NULL)
1818 	    Buf_AddByte(buf, (Byte)'\\');
1819 	Buf_AddByte(buf, (Byte)*str);
1820     }
1821     Buf_AddByte(buf, (Byte)'\0');
1822     str = (char *)Buf_GetAll(buf, NULL);
1823     Buf_Destroy(buf, FALSE);
1824     return str;
1825 }
1826 
1827 /*-
1828  *-----------------------------------------------------------------------
1829  * VarChangeCase --
1830  *      Change the string to all uppercase or all lowercase
1831  *
1832  * Input:
1833  *	str		String to modify
1834  *	upper		TRUE -> uppercase, else lowercase
1835  *
1836  * Results:
1837  *      The string with case changed
1838  *
1839  * Side Effects:
1840  *      None.
1841  *
1842  *-----------------------------------------------------------------------
1843  */
1844 static char *
1845 VarChangeCase(char *str, int upper)
1846 {
1847    Buffer         buf;
1848    int            (*modProc)(int);
1849 
1850    modProc = (upper ? toupper : tolower);
1851    buf = Buf_Init(MAKE_BSIZE);
1852    for (; *str ; str++) {
1853        Buf_AddByte(buf, (Byte)modProc(*str));
1854    }
1855    Buf_AddByte(buf, (Byte)'\0');
1856    str = (char *)Buf_GetAll(buf, NULL);
1857    Buf_Destroy(buf, FALSE);
1858    return str;
1859 }
1860 
1861 /*-
1862  *-----------------------------------------------------------------------
1863  * Var_Parse --
1864  *	Given the start of a variable invocation, extract the variable
1865  *	name and find its value, then modify it according to the
1866  *	specification.
1867  *
1868  * Input:
1869  *	str		The string to parse
1870  *	ctxt		The context for the variable
1871  *	err		TRUE if undefined variables are an error
1872  *	lengthPtr	OUT: The length of the specification
1873  *	freePtr		OUT: TRUE if caller should free result
1874  *
1875  * Results:
1876  *	The (possibly-modified) value of the variable or var_Error if the
1877  *	specification is invalid. The length of the specification is
1878  *	placed in *lengthPtr (for invalid specifications, this is just
1879  *	2...?).
1880  *	A Boolean in *freePtr telling whether the returned string should
1881  *	be freed by the caller.
1882  *
1883  * Side Effects:
1884  *	None.
1885  *
1886  *-----------------------------------------------------------------------
1887  */
1888 char *
1889 Var_Parse(const char *str, GNode *ctxt, Boolean err, int *lengthPtr,
1890 	  Boolean *freePtr)
1891 {
1892     const char	   *tstr;    	/* Pointer into str */
1893     Var	    	   *v;	    	/* Variable in invocation */
1894     const char     *cp;    	/* Secondary pointer into str (place marker
1895 				 * for tstr) */
1896     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
1897     char	    endc;    	/* Ending character when variable in parens
1898 				 * or braces */
1899     char	    startc=0;	/* Starting character when variable in parens
1900 				 * or braces */
1901     int             cnt;	/* Used to count brace pairs when variable in
1902 				 * in parens or braces */
1903     int		    vlen;	/* Length of variable name */
1904     const char 	   *start;
1905     char	    delim;
1906     char	   *nstr;
1907     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
1908 				 * expanding it in a non-local context. This
1909 				 * is done to support dynamic sources. The
1910 				 * result is just the invocation, unaltered */
1911     Var_Parse_State parsestate; /* Flags passed to helper functions */
1912 
1913     *freePtr = FALSE;
1914     dynamic = FALSE;
1915     start = str;
1916     parsestate.oneBigWord = FALSE;
1917     parsestate.varSpace = ' ';	/* word separator */
1918 
1919     if (str[1] != PROPEN && str[1] != BROPEN) {
1920 	/*
1921 	 * If it's not bounded by braces of some sort, life is much simpler.
1922 	 * We just need to check for the first character and return the
1923 	 * value if it exists.
1924 	 */
1925 	char	  name[2];
1926 
1927 	name[0] = str[1];
1928 	name[1] = '\0';
1929 
1930 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1931 	if (v == (Var *)NIL) {
1932 	    *lengthPtr = 2;
1933 
1934 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
1935 		/*
1936 		 * If substituting a local variable in a non-local context,
1937 		 * assume it's for dynamic source stuff. We have to handle
1938 		 * this specially and return the longhand for the variable
1939 		 * with the dollar sign escaped so it makes it back to the
1940 		 * caller. Only four of the local variables are treated
1941 		 * specially as they are the only four that will be set
1942 		 * when dynamic sources are expanded.
1943 		 */
1944 		switch (str[1]) {
1945 		    case '@':
1946 			return UNCONST("$(.TARGET)");
1947 		    case '%':
1948 			return UNCONST("$(.ARCHIVE)");
1949 		    case '*':
1950 			return UNCONST("$(.PREFIX)");
1951 		    case '!':
1952 			return UNCONST("$(.MEMBER)");
1953 		}
1954 	    }
1955 	    /*
1956 	     * Error
1957 	     */
1958 	    return (err ? var_Error : varNoError);
1959 	} else {
1960 	    haveModifier = FALSE;
1961 	    tstr = &str[1];
1962 	    endc = str[1];
1963 	}
1964     } else if (str[1] == '\0') {
1965 	*lengthPtr = 1;
1966 	return (err ? var_Error : varNoError);
1967     } else {
1968 	Buffer buf;	/* Holds the variable name */
1969 
1970 	startc = str[1];
1971 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
1972 	buf = Buf_Init(MAKE_BSIZE);
1973 
1974 	/*
1975 	 * Skip to the end character or a colon, whichever comes first.
1976 	 */
1977 	for (tstr = str + 2;
1978 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
1979 	     tstr++)
1980 	{
1981 	    /*
1982 	     * A variable inside a variable, expand
1983 	     */
1984 	    if (*tstr == '$') {
1985 		int rlen;
1986 		Boolean rfree;
1987 		char *rval = Var_Parse(tstr, ctxt, err, &rlen, &rfree);
1988 		if (rval != NULL) {
1989 		    Buf_AddBytes(buf, strlen(rval), (Byte *)rval);
1990 		    if (rfree)
1991 			free(rval);
1992 		}
1993 		tstr += rlen - 1;
1994 	    }
1995 	    else
1996 		Buf_AddByte(buf, (Byte)*tstr);
1997 	}
1998 	if (*tstr == ':') {
1999 	    haveModifier = TRUE;
2000 	} else if (*tstr != '\0') {
2001 	    haveModifier = FALSE;
2002 	} else {
2003 	    /*
2004 	     * If we never did find the end character, return NULL
2005 	     * right now, setting the length to be the distance to
2006 	     * the end of the string, since that's what make does.
2007 	     */
2008 	    *lengthPtr = tstr - str;
2009 	    return (var_Error);
2010 	}
2011 	*WR(tstr) = '\0';
2012 	Buf_AddByte(buf, (Byte)'\0');
2013 	str = Buf_GetAll(buf, NULL);
2014 	vlen = strlen(str);
2015 
2016 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
2017 	if ((v == (Var *)NIL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
2018 	    (vlen == 2) && (str[1] == 'F' || str[1] == 'D'))
2019 	{
2020 	    /*
2021 	     * Check for bogus D and F forms of local variables since we're
2022 	     * in a local context and the name is the right length.
2023 	     */
2024 	    switch(*str) {
2025 		case '@':
2026 		case '%':
2027 		case '*':
2028 		case '!':
2029 		case '>':
2030 		case '<':
2031 		{
2032 		    char    vname[2];
2033 		    char    *val;
2034 
2035 		    /*
2036 		     * Well, it's local -- go look for it.
2037 		     */
2038 		    vname[0] = *str;
2039 		    vname[1] = '\0';
2040 		    v = VarFind(vname, ctxt, 0);
2041 
2042 		    if (v != (Var *)NIL) {
2043 			/*
2044 			 * No need for nested expansion or anything, as we're
2045 			 * the only one who sets these things and we sure don't
2046 			 * but nested invocations in them...
2047 			 */
2048 			val = (char *)Buf_GetAll(v->val, NULL);
2049 
2050 			if (str[1] == 'D') {
2051 			    val = VarModify(ctxt, &parsestate, val, VarHead,
2052 					    (ClientData)0);
2053 			} else {
2054 			    val = VarModify(ctxt, &parsestate, val, VarTail,
2055 					    (ClientData)0);
2056 			}
2057 			/*
2058 			 * Resulting string is dynamically allocated, so
2059 			 * tell caller to free it.
2060 			 */
2061 			*freePtr = TRUE;
2062 			*lengthPtr = tstr-start+1;
2063 			*WR(tstr) = endc;
2064 			Buf_Destroy(buf, TRUE);
2065 			return(val);
2066 		    }
2067 		    break;
2068 		}
2069 	    }
2070 	}
2071 
2072 	if (v == (Var *)NIL) {
2073 	    if (((vlen == 1) ||
2074 		 (((vlen == 2) && (str[1] == 'F' ||
2075 					 str[1] == 'D')))) &&
2076 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
2077 	    {
2078 		/*
2079 		 * If substituting a local variable in a non-local context,
2080 		 * assume it's for dynamic source stuff. We have to handle
2081 		 * this specially and return the longhand for the variable
2082 		 * with the dollar sign escaped so it makes it back to the
2083 		 * caller. Only four of the local variables are treated
2084 		 * specially as they are the only four that will be set
2085 		 * when dynamic sources are expanded.
2086 		 */
2087 		switch (*str) {
2088 		    case '@':
2089 		    case '%':
2090 		    case '*':
2091 		    case '!':
2092 			dynamic = TRUE;
2093 			break;
2094 		}
2095 	    } else if ((vlen > 2) && (*str == '.') &&
2096 		       isupper((unsigned char) str[1]) &&
2097 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
2098 	    {
2099 		int	len;
2100 
2101 		len = vlen - 1;
2102 		if ((strncmp(str, ".TARGET", len) == 0) ||
2103 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
2104 		    (strncmp(str, ".PREFIX", len) == 0) ||
2105 		    (strncmp(str, ".MEMBER", len) == 0))
2106 		{
2107 		    dynamic = TRUE;
2108 		}
2109 	    }
2110 
2111 	    if (!haveModifier) {
2112 		/*
2113 		 * No modifiers -- have specification length so we can return
2114 		 * now.
2115 		 */
2116 		*lengthPtr = tstr - start + 1;
2117 		*WR(tstr) = endc;
2118 		if (dynamic) {
2119 		    char *pstr = emalloc(*lengthPtr + 1);
2120 		    strncpy(pstr, start, *lengthPtr);
2121 		    pstr[*lengthPtr] = '\0';
2122 		    *freePtr = TRUE;
2123 		    Buf_Destroy(buf, TRUE);
2124 		    return(pstr);
2125 		} else {
2126 		    Buf_Destroy(buf, TRUE);
2127 		    return (err ? var_Error : varNoError);
2128 		}
2129 	    } else {
2130 		/*
2131 		 * Still need to get to the end of the variable specification,
2132 		 * so kludge up a Var structure for the modifications
2133 		 */
2134 		v = emalloc(sizeof(Var));
2135 		v->name = UNCONST(str);
2136 		v->val = Buf_Init(1);
2137 		v->flags = VAR_JUNK;
2138 		Buf_Destroy(buf, FALSE);
2139 	    }
2140 	} else
2141 	    Buf_Destroy(buf, TRUE);
2142     }
2143 
2144 
2145     if (v->flags & VAR_IN_USE) {
2146 	Fatal("Variable %s is recursive.", v->name);
2147 	/*NOTREACHED*/
2148     } else {
2149 	v->flags |= VAR_IN_USE;
2150     }
2151     /*
2152      * Before doing any modification, we have to make sure the value
2153      * has been fully expanded. If it looks like recursion might be
2154      * necessary (there's a dollar sign somewhere in the variable's value)
2155      * we just call Var_Subst to do any other substitutions that are
2156      * necessary. Note that the value returned by Var_Subst will have
2157      * been dynamically-allocated, so it will need freeing when we
2158      * return.
2159      */
2160     nstr = (char *)Buf_GetAll(v->val, NULL);
2161     if (strchr(nstr, '$') != NULL) {
2162 	nstr = Var_Subst(NULL, nstr, ctxt, err);
2163 	*freePtr = TRUE;
2164     }
2165 
2166     v->flags &= ~VAR_IN_USE;
2167 
2168     /*
2169      * Now we need to apply any modifiers the user wants applied.
2170      * These are:
2171      *  	  :M<pattern>	words which match the given <pattern>.
2172      *  	  	    	<pattern> is of the standard file
2173      *  	  	    	wildcarding form.
2174      *  	  :N<pattern>	words which do not match the given <pattern>.
2175      *  	  :S<d><pat1><d><pat2><d>[1gW]
2176      *  	  	    	Substitute <pat2> for <pat1> in the value
2177      *  	  :C<d><pat1><d><pat2><d>[1gW]
2178      *  	  	    	Substitute <pat2> for regex <pat1> in the value
2179      *  	  :H	    	Substitute the head of each word
2180      *  	  :T	    	Substitute the tail of each word
2181      *  	  :E	    	Substitute the extension (minus '.') of
2182      *  	  	    	each word
2183      *  	  :R	    	Substitute the root of each word
2184      *  	  	    	(pathname minus the suffix).
2185      *		  :O		("Order") Alphabeticaly sort words in variable.
2186      *		  :Ox		("intermiX") Randomize words in variable.
2187      *		  :u		("uniq") Remove adjacent duplicate words.
2188      *		  :tu		Converts the variable contents to uppercase.
2189      *		  :tl		Converts the variable contents to lowercase.
2190      *		  :ts[c]	Sets varSpace - the char used to
2191      *				separate words to 'c'. If 'c' is
2192      *				omitted then no separation is used.
2193      *		  :tW		Treat the variable contents as a single
2194      *				word, even if it contains spaces.
2195      *				(Mnemonic: one big 'W'ord.)
2196      *		  :tw		Treat the variable contents as multiple
2197      *				space-separated words.
2198      *				(Mnemonic: many small 'w'ords.)
2199      *		  :[index]	Select a single word from the value.
2200      *		  :[start..end]	Select multiple words from the value.
2201      *		  :[*] or :[0]	Select the entire value, as a single
2202      *				word.  Equivalent to :tW.
2203      *		  :[@]		Select the entire value, as multiple
2204      *				words.	Undoes the effect of :[*].
2205      *				Equivalent to :tw.
2206      *		  :[#]		Returns the number of words in the value.
2207      *
2208      *		  :?<true-value>:<false-value>
2209      *				If the variable evaluates to true, return
2210      *				true value, else return the second value.
2211      *	    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
2212      *	    	    	    	the invocation.
2213      *		  :sh		Treat the current value as a command
2214      *				to be run, new value is its output.
2215      * The following added so we can handle ODE makefiles.
2216      *		  :@<tmpvar>@<newval>@
2217      *				Assign a temporary local variable <tmpvar>
2218      *				to the current value of each word in turn
2219      *				and replace each word with the result of
2220      *				evaluating <newval>
2221      *		  :D<newval>	Use <newval> as value if variable defined
2222      *		  :U<newval>	Use <newval> as value if variable undefined
2223      *		  :L		Use the name of the variable as the value.
2224      *		  :P		Use the path of the node that has the same
2225      *				name as the variable as the value.  This
2226      *				basically includes an implied :L so that
2227      *				the common method of refering to the path
2228      *				of your dependent 'x' in a rule is to use
2229      *				the form '${x:P}'.
2230      *		  :!<cmd>!	Run cmd much the same as :sh run's the
2231      *				current value of the variable.
2232      * The ::= modifiers, actually assign a value to the variable.
2233      * Their main purpose is in supporting modifiers of .for loop
2234      * iterators and other obscure uses.  They always expand to
2235      * nothing.  In a target rule that would otherwise expand to an
2236      * empty line they can be preceded with @: to keep make happy.
2237      * Eg.
2238      *
2239      * foo:	.USE
2240      * .for i in ${.TARGET} ${.TARGET:R}.gz
2241      * 		@: ${t::=$i}
2242      *		@echo blah ${t:T}
2243      * .endfor
2244      *
2245      *		  ::=<str>	Assigns <str> as the new value of variable.
2246      *		  ::?=<str>	Assigns <str> as value of variable if
2247      *				it was not already set.
2248      *		  ::+=<str>	Appends <str> to variable.
2249      *		  ::!=<cmd>	Assigns output of <cmd> as the new value of
2250      *				variable.
2251      */
2252     if ((nstr != NULL) && haveModifier) {
2253 	/*
2254 	 * Skip initial colon while putting it back.
2255 	 */
2256 	*WR(tstr) = ':';
2257 	tstr++;
2258 	delim = '\0';
2259 
2260 	while (*tstr && *tstr != endc) {
2261 	    char	*newStr;    /* New value to return */
2262 	    char	termc;	    /* Character which terminated scan */
2263 
2264 	    if (DEBUG(VAR)) {
2265 		printf("Applying :%c to \"%s\"\n", *tstr, nstr);
2266 	    }
2267 	    newStr = var_Error;
2268 	    switch (*tstr) {
2269 	        case ':':
2270 		{
2271 		if (tstr[1] == '=' ||
2272 		    (tstr[2] == '=' &&
2273 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
2274 		    /*
2275 		     * "::=", "::!=", "::+=", or "::?="
2276 		     */
2277 		    GNode *v_ctxt;		/* context where v belongs */
2278 		    const char *emsg;
2279 		    char *sv_name;
2280 		    VarPattern	pattern;
2281 		    int	how;
2282 
2283 		    v_ctxt = ctxt;
2284 		    sv_name = NULL;
2285 		    ++tstr;
2286 		    if (v->flags & VAR_JUNK) {
2287 			/*
2288 			 * We need to strdup() it incase
2289 			 * VarGetPattern() recurses.
2290 			 */
2291 			sv_name = v->name;
2292 			v->name = strdup(v->name);
2293 		    } else if (ctxt != VAR_GLOBAL) {
2294 			if (VarFind(v->name, ctxt, 0) == (Var *)NIL)
2295 			    v_ctxt = VAR_GLOBAL;
2296 		    }
2297 
2298 		    switch ((how = *tstr)) {
2299 		    case '+':
2300 		    case '?':
2301 		    case '!':
2302 			cp = &tstr[2];
2303 			break;
2304 		    default:
2305 			cp = ++tstr;
2306 			break;
2307 		    }
2308 		    delim = BRCLOSE;
2309 		    pattern.flags = 0;
2310 
2311 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, err,
2312 						     &cp, delim, NULL,
2313 						     &pattern.rightLen,
2314 						     NULL);
2315 		    if (v->flags & VAR_JUNK) {
2316 			/* restore original name */
2317 			free(v->name);
2318 			v->name = sv_name;
2319 		    }
2320 		    if (pattern.rhs == NULL)
2321 			goto cleanup;
2322 
2323 		    termc = *--cp;
2324 		    delim = '\0';
2325 
2326 		    switch (how) {
2327 		    case '+':
2328 			Var_Append(v->name, pattern.rhs, v_ctxt);
2329 			break;
2330 		    case '!':
2331 			newStr = Cmd_Exec(pattern.rhs, &emsg);
2332 			if (emsg)
2333 			    Error(emsg, nstr);
2334 			else
2335 			   Var_Set(v->name, newStr,  v_ctxt, 0);
2336 			if (newStr)
2337 			    free(newStr);
2338 			break;
2339 		    case '?':
2340 			if ((v->flags & VAR_JUNK) == 0)
2341 			    break;
2342 			/* FALLTHROUGH */
2343 		    default:
2344 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
2345 			break;
2346 		    }
2347 		    free(UNCONST(pattern.rhs));
2348 		    newStr = var_Error;
2349 		    break;
2350 		}
2351 		goto default_case; /* "::<unrecognised>" */
2352 		}
2353 	        case '@':
2354 		{
2355 		    VarLoop_t	loop;
2356 		    int flags = VAR_NOSUBST;
2357 
2358 		    cp = ++tstr;
2359 		    delim = '@';
2360 		    if ((loop.tvar = VarGetPattern(ctxt, &parsestate, err,
2361 						   &cp, delim,
2362 						   &flags, &loop.tvarLen,
2363 						   NULL)) == NULL)
2364 			goto cleanup;
2365 
2366 		    if ((loop.str = VarGetPattern(ctxt, &parsestate, err,
2367 						  &cp, delim,
2368 						  &flags, &loop.strLen,
2369 						  NULL)) == NULL)
2370 			goto cleanup;
2371 
2372 		    termc = *cp;
2373 		    delim = '\0';
2374 
2375 		    loop.err = err;
2376 		    loop.ctxt = ctxt;
2377 		    newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
2378 				       (ClientData)&loop);
2379 		    free(loop.tvar);
2380 		    free(loop.str);
2381 		    break;
2382 		}
2383 	        case 'D':
2384 	        case 'U':
2385 		{
2386 		    Buffer  buf;    	/* Buffer for patterns */
2387 		    int	    wantit;	/* want data in buffer */
2388 
2389 		    /*
2390 		     * Pass through tstr looking for 1) escaped delimiters,
2391 		     * '$'s and backslashes (place the escaped character in
2392 		     * uninterpreted) and 2) unescaped $'s that aren't before
2393 		     * the delimiter (expand the variable substitution).
2394 		     * The result is left in the Buffer buf.
2395 		     */
2396 		    buf = Buf_Init(0);
2397 		    for (cp = tstr + 1;
2398 			 *cp != endc && *cp != ':' && *cp != '\0';
2399 			 cp++) {
2400 			if ((*cp == '\\') &&
2401 			    ((cp[1] == ':') ||
2402 			     (cp[1] == '$') ||
2403 			     (cp[1] == endc) ||
2404 			     (cp[1] == '\\')))
2405 			{
2406 			    Buf_AddByte(buf, (Byte)cp[1]);
2407 			    cp++;
2408 			} else if (*cp == '$') {
2409 			    /*
2410 			     * If unescaped dollar sign, assume it's a
2411 			     * variable substitution and recurse.
2412 			     */
2413 			    char    *cp2;
2414 			    int	    len;
2415 			    Boolean freeIt;
2416 
2417 			    cp2 = Var_Parse(cp, ctxt, err, &len, &freeIt);
2418 			    Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
2419 			    if (freeIt)
2420 				free(cp2);
2421 			    cp += len - 1;
2422 			} else {
2423 			    Buf_AddByte(buf, (Byte)*cp);
2424 			}
2425 		    }
2426 		    Buf_AddByte(buf, (Byte)'\0');
2427 
2428 		    termc = *cp;
2429 
2430 		    if (*tstr == 'U')
2431 			wantit = ((v->flags & VAR_JUNK) != 0);
2432 		    else
2433 			wantit = ((v->flags & VAR_JUNK) == 0);
2434 		    if ((v->flags & VAR_JUNK) != 0)
2435 			v->flags |= VAR_KEEP;
2436 		    if (wantit) {
2437 			newStr = (char *)Buf_GetAll(buf, NULL);
2438 			Buf_Destroy(buf, FALSE);
2439 		    } else {
2440 			newStr = nstr;
2441 			Buf_Destroy(buf, TRUE);
2442 		    }
2443 		    break;
2444 		}
2445 	        case 'L':
2446 		{
2447 		    if ((v->flags & VAR_JUNK) != 0)
2448 			v->flags |= VAR_KEEP;
2449 		    newStr = strdup(v->name);
2450 		    cp = ++tstr;
2451 		    termc = *tstr;
2452 		    break;
2453 		}
2454 	        case 'P':
2455 		{
2456 		    GNode *gn;
2457 
2458 		    if ((v->flags & VAR_JUNK) != 0)
2459 			v->flags |= VAR_KEEP;
2460 		    gn = Targ_FindNode(v->name, TARG_NOCREATE);
2461 		    if (gn == NILGNODE || gn->path == NULL)
2462 			newStr = strdup(v->name);
2463 		    else
2464 			newStr = strdup(gn->path);
2465 		    cp = ++tstr;
2466 		    termc = *tstr;
2467 		    break;
2468 		}
2469 	        case '!':
2470 		{
2471 		    const char *emsg;
2472 		    VarPattern 	    pattern;
2473 		    pattern.flags = 0;
2474 
2475 		    delim = '!';
2476 
2477 		    cp = ++tstr;
2478 		    if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, err,
2479 						     &cp, delim,
2480 						     NULL, &pattern.rightLen,
2481 						     NULL)) == NULL)
2482 			goto cleanup;
2483 		    newStr = Cmd_Exec(pattern.rhs, &emsg);
2484 		    free(UNCONST(pattern.rhs));
2485 		    if (emsg)
2486 			Error(emsg, nstr);
2487 		    termc = *cp;
2488 		    delim = '\0';
2489 		    if (v->flags & VAR_JUNK) {
2490 			v->flags |= VAR_KEEP;
2491 		    }
2492 		    break;
2493 		}
2494 		case '[':
2495 		{
2496 		    /*
2497 		     * Look for the closing ']', recursively
2498 		     * expanding any embedded variables.
2499 		     *
2500 		     * estr is a pointer to the expanded result,
2501 		     * which we must free().
2502 		     */
2503 		    char *estr;
2504 
2505 		    cp = tstr+1; /* point to char after '[' */
2506 		    delim = ']'; /* look for closing ']' */
2507 		    estr = VarGetPattern(ctxt, &parsestate,
2508 					 err, &cp, delim,
2509 					 NULL, NULL, NULL);
2510 		    if (estr == NULL)
2511 			goto cleanup; /* report missing ']' */
2512 		    /* now cp points just after the closing ']' */
2513 		    delim = '\0';
2514 		    if (cp[0] != ':' && cp[0] != endc) {
2515 			/* Found junk after ']' */
2516 			free(estr);
2517 			goto bad_modifier;
2518 		    }
2519 		    if (estr[0] == '\0') {
2520 			/* Found empty square brackets in ":[]". */
2521 			free(estr);
2522 			goto bad_modifier;
2523 		    } else if (estr[0] == '#' && estr[1] == '\0') {
2524 			/* Found ":[#]" */
2525 
2526 			/*
2527 			 * We will need enough space for the decimal
2528 			 * representation of an int.  We calculate the
2529 			 * space needed for the octal representation,
2530 			 * and add enough slop to cope with a '-' sign
2531 			 * (which should never be needed) and a '\0'
2532 			 * string terminator.
2533 			 */
2534 			 int newStrSize =
2535 				 (sizeof(int) * CHAR_BIT + 2) / 3 + 2;
2536 
2537 			newStr = emalloc(newStrSize);
2538 			if (parsestate.oneBigWord) {
2539 				strncpy(newStr, "1", newStrSize);
2540 			} else {
2541 			    /* XXX: brk_string() is a rather expensive
2542 			     * way of counting words. */
2543 			    char **av;
2544 			    char *as;
2545 			    int ac;
2546 
2547 			    av = brk_string(nstr, &ac, FALSE, &as);
2548 			    snprintf(newStr, newStrSize,  "%d", ac);
2549 			    free(as);
2550 			    free(av);
2551 			}
2552 			termc = *cp;
2553 			free(estr);
2554 			break;
2555 		    } else if (estr[0] == '*' && estr[1] == '\0') {
2556 			/* Found ":[*]" */
2557 			parsestate.oneBigWord = TRUE;
2558 			newStr = nstr;
2559 			termc = *cp;
2560 			free(estr);
2561 			break;
2562 		    } else if (estr[0] == '@' && estr[1] == '\0') {
2563 			/* Found ":[@]" */
2564 			parsestate.oneBigWord = FALSE;
2565 			newStr = nstr;
2566 			termc = *cp;
2567 			free(estr);
2568 			break;
2569 		    } else {
2570 			/*
2571 			 * We expect estr to contain a single
2572 			 * integer for :[N], or two integers
2573 			 * separated by ".." for :[start..end].
2574 			 */
2575 			char *ep;
2576 
2577 			VarSelectWords_t seldata = { 0, 0 };
2578 
2579 			seldata.start = strtol(estr, &ep, 0);
2580 			if (ep == estr) {
2581 			    /* Found junk instead of a number */
2582 			    free(estr);
2583 			    goto bad_modifier;
2584 			} else if (ep[0] == '\0') {
2585 			    /* Found only one integer in :[N] */
2586 			    seldata.end = seldata.start;
2587 			} else if (ep[0] == '.' && ep[1] == '.' &&
2588 				   ep[2] != '\0') {
2589 			    /* Expecting another integer after ".." */
2590 			    ep += 2;
2591 			    seldata.end = strtol(ep, &ep, 0);
2592 			    if (ep[0] != '\0') {
2593 				/* Found junk after ".." */
2594 				free(estr);
2595 				goto bad_modifier;
2596 			    }
2597 			} else {
2598 			    /* Found junk instead of ".." */
2599 			    free(estr);
2600 			    goto bad_modifier;
2601 			}
2602 			/*
2603 			 * Now seldata is properly filled in,
2604 			 * but we still have to check for 0 as
2605 			 * a special case.
2606 			 */
2607 			if (seldata.start == 0 && seldata.end == 0) {
2608 			    /* ":[0]" or perhaps ":[0..0]" */
2609 			    parsestate.oneBigWord = TRUE;
2610 			    newStr = nstr;
2611 			    termc = *cp;
2612 			    free(estr);
2613 			    break;
2614 			} else if (seldata.start == 0 ||
2615 				   seldata.end == 0) {
2616 			    /* ":[0..N]" or ":[N..0]" */
2617 			    free(estr);
2618 			    goto bad_modifier;
2619 			}
2620 			/*
2621 			 * Normal case: select the words
2622 			 * described by seldata.
2623 			 */
2624 			newStr = VarSelectWords(ctxt, &parsestate,
2625 						nstr, &seldata);
2626 
2627 			termc = *cp;
2628 			free(estr);
2629 			break;
2630 		    }
2631 
2632 		}
2633 	        case 't':
2634 		{
2635 		    cp = tstr + 1;	/* make sure it is set */
2636 		    if (tstr[1] != endc && tstr[1] != ':') {
2637 			if (tstr[1] == 's') {
2638 			    /*
2639 			     * Use the char (if any) at tstr[2]
2640 			     * as the word separator.
2641 			     */
2642 			    VarPattern pattern;
2643 
2644 			    if (tstr[2] != endc &&
2645 				(tstr[3] == endc || tstr[3] == ':')) {
2646 				/* ":ts<unrecognised><endc>" or
2647 				 * ":ts<unrecognised>:" */
2648 				parsestate.varSpace = tstr[2];
2649 				cp = tstr + 3;
2650 			    } else if (tstr[2] == endc || tstr[2] == ':') {
2651 				/* ":ts<endc>" or ":ts:" */
2652 				parsestate.varSpace = 0; /* no separator */
2653 				cp = tstr + 2;
2654 			    } else if (tstr[2] == '\\') {
2655 				switch (tstr[3]) {
2656 				case 'n':
2657 				    parsestate.varSpace = '\n';
2658 				    cp = tstr + 4;
2659 				    break;
2660 				case 't':
2661 				    parsestate.varSpace = '\t';
2662 				    cp = tstr + 4;
2663 				    break;
2664 				default:
2665 				    if (isdigit((unsigned char)tstr[3])) {
2666 					char *ep;
2667 
2668 					parsestate.varSpace =
2669 						strtoul(&tstr[3], &ep, 0);
2670 					if (*ep != ':' && *ep != endc)
2671 					    goto bad_modifier;
2672 					cp = ep;
2673 				    } else {
2674 					/*
2675 					 * ":ts<backslash><unrecognised>".
2676 					 */
2677 					goto bad_modifier;
2678 				    }
2679 				    break;
2680 				}
2681 			    } else {
2682 				/*
2683 				 * Found ":ts<unrecognised><unrecognised>".
2684 				 */
2685 				goto bad_modifier;
2686 			    }
2687 
2688 			    termc = *cp;
2689 
2690 			    /*
2691 			     * We cannot be certain that VarModify
2692 			     * will be used - even if there is a
2693 			     * subsequent modifier, so do a no-op
2694 			     * VarSubstitute now to for str to be
2695 			     * re-expanded without the spaces.
2696 			     */
2697 			    pattern.flags = VAR_SUB_ONE;
2698 			    pattern.lhs = pattern.rhs = "\032";
2699 			    pattern.leftLen = pattern.rightLen = 1;
2700 
2701 			    newStr = VarModify(ctxt, &parsestate, nstr,
2702 					       VarSubstitute,
2703 					       (ClientData)&pattern);
2704 			} else if (tstr[2] == endc || tstr[2] == ':') {
2705 			    /*
2706 			     * Check for two-character options:
2707 			     * ":tu", ":tl"
2708 			     */
2709                             if (tstr[1] == 'u' || tstr[1] == 'l') {
2710                                 newStr = VarChangeCase(nstr, (tstr[1] == 'u'));
2711                                 cp = tstr + 2;
2712                                 termc = *cp;
2713                             } else if (tstr[1] == 'W' || tstr[1] == 'w') {
2714 				parsestate.oneBigWord = (tstr[1] == 'W');
2715 				newStr = nstr;
2716 				cp = tstr + 2;
2717 				termc = *cp;
2718                             } else {
2719 				/* Found ":t<unrecognised>:" or
2720 				 * ":t<unrecognised><endc>". */
2721 				goto bad_modifier;
2722 			    }
2723 			} else {
2724 			    /*
2725 			     * Found ":t<unrecognised><unrecognised>".
2726 			     */
2727 			    goto bad_modifier;
2728 			}
2729 		    } else {
2730 			/*
2731 			 * Found ":t<endc>" or ":t:".
2732 			 */
2733 			goto bad_modifier;
2734 		    }
2735 		    break;
2736 		}
2737 		case 'N':
2738 		case 'M':
2739 		{
2740 		    char    *pattern;
2741 		    char    *cp2;
2742 		    Boolean copy;
2743 		    int nest;
2744 
2745 		    copy = FALSE;
2746 		    nest = 1;
2747 		    /*
2748 		     * In the loop below, ignore ':' unless we are at
2749 		     * (or back to) the original brace level.
2750 		     * XXX This will likely not work right if $() and ${}
2751 		     * are intermixed.
2752 		     */
2753 		    for (cp = tstr + 1;
2754 			 *cp != '\0' && !(*cp == ':' && nest == 1);
2755 			 cp++)
2756 		    {
2757 			if (*cp == '\\' &&
2758 			    (cp[1] == ':' ||
2759 			     cp[1] == endc || cp[1] == startc)) {
2760 			    copy = TRUE;
2761 			    cp++;
2762 			    continue;
2763 			}
2764 			if (*cp == startc)
2765 			    ++nest;
2766 			if (*cp == endc) {
2767 			    --nest;
2768 			    if (nest == 0)
2769 				break;
2770 			}
2771 		    }
2772 		    termc = *cp;
2773 		    *WR(cp) = '\0';
2774 		    if (copy) {
2775 			/*
2776 			 * Need to compress the \:'s out of the pattern, so
2777 			 * allocate enough room to hold the uncompressed
2778 			 * pattern (note that cp started at tstr+1, so
2779 			 * cp - tstr takes the null byte into account) and
2780 			 * compress the pattern into the space.
2781 			 */
2782 			pattern = emalloc(cp - tstr);
2783 			for (cp2 = pattern, cp = tstr + 1;
2784 			     *cp != '\0';
2785 			     cp++, cp2++)
2786 			{
2787 			    if ((*cp == '\\') &&
2788 				(cp[1] == ':' || cp[1] == endc)) {
2789 				    cp++;
2790 			    }
2791 			    *cp2 = *cp;
2792 			}
2793 			*cp2 = '\0';
2794 		    } else {
2795 			pattern = UNCONST(&tstr[1]);
2796 		    }
2797 		    if ((cp2 = strchr(pattern, '$'))) {
2798 			cp2 = pattern;
2799 			pattern = Var_Subst(NULL, cp2, ctxt, err);
2800 			if (copy)
2801 			    free(cp2);
2802 			copy = TRUE;
2803 		    }
2804 		    if (*tstr == 'M' || *tstr == 'm') {
2805 			newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
2806 					   (ClientData)pattern);
2807 		    } else {
2808 			newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
2809 					   (ClientData)pattern);
2810 		    }
2811 		    if (copy) {
2812 			free(pattern);
2813 		    }
2814 		    break;
2815 		}
2816 		case 'S':
2817 		{
2818 		    VarPattern 	    pattern;
2819 		    Var_Parse_State tmpparsestate;
2820 
2821 		    pattern.flags = 0;
2822 		    tmpparsestate = parsestate;
2823 		    delim = tstr[1];
2824 		    tstr += 2;
2825 
2826 		    /*
2827 		     * If pattern begins with '^', it is anchored to the
2828 		     * start of the word -- skip over it and flag pattern.
2829 		     */
2830 		    if (*tstr == '^') {
2831 			pattern.flags |= VAR_MATCH_START;
2832 			tstr += 1;
2833 		    }
2834 
2835 		    cp = tstr;
2836 		    if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, err,
2837 						     &cp, delim,
2838 						     &pattern.flags,
2839 						     &pattern.leftLen,
2840 						     NULL)) == NULL)
2841 			goto cleanup;
2842 
2843 		    if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, err,
2844 						     &cp, delim, NULL,
2845 						     &pattern.rightLen,
2846 						     &pattern)) == NULL)
2847 			goto cleanup;
2848 
2849 		    /*
2850 		     * Check for global substitution. If 'g' after the final
2851 		     * delimiter, substitution is global and is marked that
2852 		     * way.
2853 		     */
2854 		    for (;; cp++) {
2855 			switch (*cp) {
2856 			case 'g':
2857 			    pattern.flags |= VAR_SUB_GLOBAL;
2858 			    continue;
2859 			case '1':
2860 			    pattern.flags |= VAR_SUB_ONE;
2861 			    continue;
2862 			case 'W':
2863 			    tmpparsestate.oneBigWord = TRUE;
2864 			    continue;
2865 			}
2866 			break;
2867 		    }
2868 
2869 		    termc = *cp;
2870 		    newStr = VarModify(ctxt, &tmpparsestate, nstr,
2871 				       VarSubstitute,
2872 				       (ClientData)&pattern);
2873 
2874 		    /*
2875 		     * Free the two strings.
2876 		     */
2877 		    free(UNCONST(pattern.lhs));
2878 		    free(UNCONST(pattern.rhs));
2879 		    delim = '\0';
2880 		    break;
2881 		}
2882 		case '?':
2883 		{
2884 		    VarPattern 	pattern;
2885 		    Boolean	value;
2886 
2887 		    /* find ':', and then substitute accordingly */
2888 
2889 		    pattern.flags = 0;
2890 
2891 		    cp = ++tstr;
2892 		    delim = ':';
2893 		    if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, err,
2894 						     &cp, delim, NULL,
2895 						     &pattern.leftLen,
2896 						     NULL)) == NULL)
2897 			goto cleanup;
2898 
2899 			/* BROPEN or PROPEN */
2900 		    delim = endc;
2901 		    if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, err,
2902 						     &cp, delim, NULL,
2903 						     &pattern.rightLen,
2904 						     NULL)) == NULL)
2905 			goto cleanup;
2906 
2907 		    termc = *--cp;
2908 		    delim = '\0';
2909 		    if (Cond_EvalExpression(1, v->name, &value, 0)
2910 			== COND_INVALID) {
2911 			Error("Bad conditional expression `%s' in %s?%s:%s",
2912 			      v->name, v->name, pattern.lhs, pattern.rhs);
2913 			goto cleanup;
2914 		    }
2915 
2916 		    if (value) {
2917 			newStr = UNCONST(pattern.lhs);
2918 			free(UNCONST(pattern.rhs));
2919 		    } else {
2920 			newStr = UNCONST(pattern.rhs);
2921 			free(UNCONST(pattern.lhs));
2922 		    }
2923 		    if (v->flags & VAR_JUNK) {
2924 			v->flags |= VAR_KEEP;
2925 		    }
2926 		    break;
2927 		}
2928 #ifndef NO_REGEX
2929 		case 'C':
2930 		{
2931 		    VarREPattern    pattern;
2932 		    char           *re;
2933 		    int             error;
2934 		    Var_Parse_State tmpparsestate;
2935 
2936 		    pattern.flags = 0;
2937 		    tmpparsestate = parsestate;
2938 		    delim = tstr[1];
2939 		    tstr += 2;
2940 
2941 		    cp = tstr;
2942 
2943 		    if ((re = VarGetPattern(ctxt, &parsestate, err, &cp, delim,
2944 					    NULL, NULL, NULL)) == NULL)
2945 			goto cleanup;
2946 
2947 		    if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
2948 							 err, &cp, delim, NULL,
2949 							 NULL, NULL)) == NULL){
2950 			free(re);
2951 			goto cleanup;
2952 		    }
2953 
2954 		    for (;; cp++) {
2955 			switch (*cp) {
2956 			case 'g':
2957 			    pattern.flags |= VAR_SUB_GLOBAL;
2958 			    continue;
2959 			case '1':
2960 			    pattern.flags |= VAR_SUB_ONE;
2961 			    continue;
2962 			case 'W':
2963 			    tmpparsestate.oneBigWord = TRUE;
2964 			    continue;
2965 			}
2966 			break;
2967 		    }
2968 
2969 		    termc = *cp;
2970 
2971 		    error = regcomp(&pattern.re, re, REG_EXTENDED);
2972 		    free(re);
2973 		    if (error)  {
2974 			*lengthPtr = cp - start + 1;
2975 			VarREError(error, &pattern.re, "RE substitution error");
2976 			free(pattern.replace);
2977 			return (var_Error);
2978 		    }
2979 
2980 		    pattern.nsub = pattern.re.re_nsub + 1;
2981 		    if (pattern.nsub < 1)
2982 			pattern.nsub = 1;
2983 		    if (pattern.nsub > 10)
2984 			pattern.nsub = 10;
2985 		    pattern.matches = emalloc(pattern.nsub *
2986 					      sizeof(regmatch_t));
2987 		    newStr = VarModify(ctxt, &tmpparsestate, nstr,
2988 				       VarRESubstitute,
2989 				       (ClientData) &pattern);
2990 		    regfree(&pattern.re);
2991 		    free(pattern.replace);
2992 		    free(pattern.matches);
2993 		    delim = '\0';
2994 		    break;
2995 		}
2996 #endif
2997 		case 'Q':
2998 		    if (tstr[1] == endc || tstr[1] == ':') {
2999 			newStr = VarQuote(nstr);
3000 			cp = tstr + 1;
3001 			termc = *cp;
3002 			break;
3003 		    }
3004 		    goto default_case;
3005 		case 'T':
3006 		    if (tstr[1] == endc || tstr[1] == ':') {
3007 			newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
3008 					   (ClientData)0);
3009 			cp = tstr + 1;
3010 			termc = *cp;
3011 			break;
3012 		    }
3013 		    goto default_case;
3014 		case 'H':
3015 		    if (tstr[1] == endc || tstr[1] == ':') {
3016 			newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
3017 					   (ClientData)0);
3018 			cp = tstr + 1;
3019 			termc = *cp;
3020 			break;
3021 		    }
3022 		    goto default_case;
3023 		case 'E':
3024 		    if (tstr[1] == endc || tstr[1] == ':') {
3025 			newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
3026 					   (ClientData)0);
3027 			cp = tstr + 1;
3028 			termc = *cp;
3029 			break;
3030 		    }
3031 		    goto default_case;
3032 		case 'R':
3033 		    if (tstr[1] == endc || tstr[1] == ':') {
3034 			newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
3035 					   (ClientData)0);
3036 			cp = tstr + 1;
3037 			termc = *cp;
3038 			break;
3039 		    }
3040 		    goto default_case;
3041 		case 'O':
3042 		{
3043 		    char otype;
3044 
3045 		    cp = tstr + 1;	/* skip to the rest in any case */
3046 		    if (tstr[1] == endc || tstr[1] == ':') {
3047 			otype = 's';
3048 			termc = *cp;
3049 		    } else if ( (tstr[1] == 'x') &&
3050 		    		(tstr[2] == endc || tstr[2] == ':') ) {
3051 			otype = tstr[1];
3052 			cp = tstr + 2;
3053 			termc = *cp;
3054 		    } else {
3055 			goto bad_modifier;
3056 		    }
3057 		    newStr = VarOrder(nstr, otype);
3058 		    break;
3059 		}
3060 		case 'u':
3061 		    if (tstr[1] == endc || tstr[1] == ':') {
3062 			newStr = VarUniq(nstr);
3063 			cp = tstr + 1;
3064 			termc = *cp;
3065 			break;
3066 		    }
3067 		    goto default_case;
3068 #ifdef SUNSHCMD
3069 		case 's':
3070 		    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
3071 			const char *emsg;
3072 			newStr = Cmd_Exec(nstr, &emsg);
3073 			if (emsg)
3074 			    Error(emsg, nstr);
3075 			cp = tstr + 2;
3076 			termc = *cp;
3077 			break;
3078 		    }
3079 		    goto default_case;
3080 #endif
3081                 default:
3082 		default_case:
3083 		{
3084 #ifdef SYSVVARSUB
3085 		    /*
3086 		     * This can either be a bogus modifier or a System-V
3087 		     * substitution command.
3088 		     */
3089 		    VarPattern      pattern;
3090 		    Boolean         eqFound;
3091 
3092 		    pattern.flags = 0;
3093 		    eqFound = FALSE;
3094 		    /*
3095 		     * First we make a pass through the string trying
3096 		     * to verify it is a SYSV-make-style translation:
3097 		     * it must be: <string1>=<string2>)
3098 		     */
3099 		    cp = tstr;
3100 		    cnt = 1;
3101 		    while (*cp != '\0' && cnt) {
3102 			if (*cp == '=') {
3103 			    eqFound = TRUE;
3104 			    /* continue looking for endc */
3105 			}
3106 			else if (*cp == endc)
3107 			    cnt--;
3108 			else if (*cp == startc)
3109 			    cnt++;
3110 			if (cnt)
3111 			    cp++;
3112 		    }
3113 		    if (*cp == endc && eqFound) {
3114 
3115 			/*
3116 			 * Now we break this sucker into the lhs and
3117 			 * rhs. We must null terminate them of course.
3118 			 */
3119 			delim='=';
3120 			cp = tstr;
3121 			if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
3122 				err, &cp, delim, &pattern.flags,
3123 				&pattern.leftLen, NULL)) == NULL)
3124 				goto cleanup;
3125 			delim = endc;
3126 			if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
3127 				err, &cp, delim, NULL, &pattern.rightLen,
3128 				&pattern)) == NULL)
3129 				goto cleanup;
3130 
3131 			/*
3132 			 * SYSV modifications happen through the whole
3133 			 * string. Note the pattern is anchored at the end.
3134 			 */
3135 			termc = *--cp;
3136 			delim = '\0';
3137 			newStr = VarModify(ctxt, &parsestate, nstr,
3138 					   VarSYSVMatch,
3139 					   (ClientData)&pattern);
3140 			free(UNCONST(pattern.lhs));
3141 			free(UNCONST(pattern.rhs));
3142 		    } else
3143 #endif
3144 		    {
3145 			Error("Unknown modifier '%c'", *tstr);
3146 			for (cp = tstr+1;
3147 			     *cp != ':' && *cp != endc && *cp != '\0';
3148 			     cp++)
3149 				 continue;
3150 			termc = *cp;
3151 			newStr = var_Error;
3152 		    }
3153 		}
3154 	    }
3155 	    if (DEBUG(VAR)) {
3156 		printf("Result is \"%s\"\n", newStr);
3157 	    }
3158 
3159 	    if (newStr != nstr) {
3160 		if (*freePtr) {
3161 		    free(nstr);
3162 		}
3163 		nstr = newStr;
3164 		if (nstr != var_Error && nstr != varNoError) {
3165 		    *freePtr = TRUE;
3166 		} else {
3167 		    *freePtr = FALSE;
3168 		}
3169 	    }
3170 	    if (termc == '\0') {
3171 		Error("Unclosed variable specification for %s", v->name);
3172 	    } else if (termc == ':') {
3173 		*WR(cp) = termc;
3174 		cp++;
3175 	    } else {
3176 		*WR(cp) = termc;
3177 	    }
3178 	    tstr = cp;
3179 	}
3180 	*lengthPtr = tstr - start + 1;
3181     } else {
3182 	*lengthPtr = tstr - start + 1;
3183 	*WR(tstr) = endc;
3184     }
3185 
3186     if (v->flags & VAR_FROM_ENV) {
3187 	Boolean	  destroy = FALSE;
3188 
3189 	if (nstr != (char *)Buf_GetAll(v->val, NULL)) {
3190 	    destroy = TRUE;
3191 	} else {
3192 	    /*
3193 	     * Returning the value unmodified, so tell the caller to free
3194 	     * the thing.
3195 	     */
3196 	    *freePtr = TRUE;
3197 	}
3198 	if (nstr != (char *)Buf_GetAll(v->val, NULL))
3199 	    Buf_Destroy(v->val, destroy);
3200 	free(v->name);
3201 	free(v);
3202     } else if (v->flags & VAR_JUNK) {
3203 	/*
3204 	 * Perform any free'ing needed and set *freePtr to FALSE so the caller
3205 	 * doesn't try to free a static pointer.
3206 	 * If VAR_KEEP is also set then we want to keep str as is.
3207 	 */
3208 	if (!(v->flags & VAR_KEEP)) {
3209 	    if (*freePtr) {
3210 		free(nstr);
3211 	    }
3212 	    *freePtr = FALSE;
3213 	    if (dynamic) {
3214 		nstr = emalloc(*lengthPtr + 1);
3215 		strncpy(nstr, start, *lengthPtr);
3216 		nstr[*lengthPtr] = '\0';
3217 		*freePtr = TRUE;
3218 	    } else {
3219 		nstr = var_Error;
3220 	    }
3221 	}
3222 	if (nstr != (char *)Buf_GetAll(v->val, NULL))
3223 	    Buf_Destroy(v->val, TRUE);
3224 	free(v->name);
3225 	free(v);
3226     }
3227     return (nstr);
3228 
3229  bad_modifier:
3230 							/* "{(" */
3231     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
3232 	  v->name);
3233 
3234 cleanup:
3235     *lengthPtr = cp - start + 1;
3236     if (*freePtr)
3237 	free(nstr);
3238     if (delim != '\0')
3239 	Error("Unclosed substitution for %s (%c missing)",
3240 	      v->name, delim);
3241     return (var_Error);
3242 }
3243 
3244 /*-
3245  *-----------------------------------------------------------------------
3246  * Var_Subst  --
3247  *	Substitute for all variables in the given string in the given context
3248  *	If undefErr is TRUE, Parse_Error will be called when an undefined
3249  *	variable is encountered.
3250  *
3251  * Input:
3252  *	var		Named variable || NULL for all
3253  *	str		the string which to substitute
3254  *	ctxt		the context wherein to find variables
3255  *	undefErr	TRUE if undefineds are an error
3256  *
3257  * Results:
3258  *	The resulting string.
3259  *
3260  * Side Effects:
3261  *	None. The old string must be freed by the caller
3262  *-----------------------------------------------------------------------
3263  */
3264 char *
3265 Var_Subst(const char *var, const char *str, GNode *ctxt, Boolean undefErr)
3266 {
3267     Buffer  	  buf;	    	    /* Buffer for forming things */
3268     char    	  *val;		    /* Value to substitute for a variable */
3269     int	    	  length;   	    /* Length of the variable invocation */
3270     Boolean	  trailingBslash;   /* variable ends in \ */
3271     Boolean 	  doFree;   	    /* Set true if val should be freed */
3272     static Boolean errorReported;   /* Set true if an error has already
3273 				     * been reported to prevent a plethora
3274 				     * of messages when recursing */
3275 
3276     buf = Buf_Init(MAKE_BSIZE);
3277     errorReported = FALSE;
3278     trailingBslash = FALSE;
3279 
3280     while (*str) {
3281 	if (*str == '\n' && trailingBslash)
3282 	    Buf_AddByte(buf, ' ');
3283 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
3284 	    /*
3285 	     * A dollar sign may be escaped either with another dollar sign.
3286 	     * In such a case, we skip over the escape character and store the
3287 	     * dollar sign into the buffer directly.
3288 	     */
3289 	    str++;
3290 	    Buf_AddByte(buf, (Byte)*str);
3291 	    str++;
3292 	} else if (*str != '$') {
3293 	    /*
3294 	     * Skip as many characters as possible -- either to the end of
3295 	     * the string or to the next dollar sign (variable invocation).
3296 	     */
3297 	    const char  *cp;
3298 
3299 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
3300 		continue;
3301 	    Buf_AddBytes(buf, str - cp, (const Byte *)cp);
3302 	} else {
3303 	    if (var != NULL) {
3304 		int expand;
3305 		for (;;) {
3306 		    if (str[1] == '\0') {
3307 			/* A trailing $ is kind of a special case */
3308 			Buf_AddByte(buf, str[0]);
3309 			str++;
3310 			expand = FALSE;
3311 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
3312 			if (str[1] != *var || strlen(var) > 1) {
3313 			    Buf_AddBytes(buf, 2, (const Byte *)str);
3314 			    str += 2;
3315 			    expand = FALSE;
3316 			}
3317 			else
3318 			    expand = TRUE;
3319 			break;
3320 		    }
3321 		    else {
3322 			const char *p;
3323 
3324 			/*
3325 			 * Scan up to the end of the variable name.
3326 			 */
3327 			for (p = &str[2]; *p &&
3328 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
3329 			    if (*p == '$')
3330 				break;
3331 			/*
3332 			 * A variable inside the variable. We cannot expand
3333 			 * the external variable yet, so we try again with
3334 			 * the nested one
3335 			 */
3336 			if (*p == '$') {
3337 			    Buf_AddBytes(buf, p - str, (const Byte *)str);
3338 			    str = p;
3339 			    continue;
3340 			}
3341 
3342 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
3343 			    var[p - str - 2] != '\0') {
3344 			    /*
3345 			     * Not the variable we want to expand, scan
3346 			     * until the next variable
3347 			     */
3348 			    for (;*p != '$' && *p != '\0'; p++)
3349 				continue;
3350 			    Buf_AddBytes(buf, p - str, (const Byte *)str);
3351 			    str = p;
3352 			    expand = FALSE;
3353 			}
3354 			else
3355 			    expand = TRUE;
3356 			break;
3357 		    }
3358 		}
3359 		if (!expand)
3360 		    continue;
3361 	    }
3362 
3363 	    val = Var_Parse(str, ctxt, undefErr, &length, &doFree);
3364 
3365 	    /*
3366 	     * When we come down here, val should either point to the
3367 	     * value of this variable, suitably modified, or be NULL.
3368 	     * Length should be the total length of the potential
3369 	     * variable invocation (from $ to end character...)
3370 	     */
3371 	    if (val == var_Error || val == varNoError) {
3372 		/*
3373 		 * If performing old-time variable substitution, skip over
3374 		 * the variable and continue with the substitution. Otherwise,
3375 		 * store the dollar sign and advance str so we continue with
3376 		 * the string...
3377 		 */
3378 		if (oldVars) {
3379 		    str += length;
3380 		} else if (undefErr) {
3381 		    /*
3382 		     * If variable is undefined, complain and skip the
3383 		     * variable. The complaint will stop us from doing anything
3384 		     * when the file is parsed.
3385 		     */
3386 		    if (!errorReported) {
3387 			Parse_Error(PARSE_FATAL,
3388 				     "Undefined variable \"%.*s\"",length,str);
3389 		    }
3390 		    str += length;
3391 		    errorReported = TRUE;
3392 		} else {
3393 		    Buf_AddByte(buf, (Byte)*str);
3394 		    str += 1;
3395 		}
3396 	    } else {
3397 		/*
3398 		 * We've now got a variable structure to store in. But first,
3399 		 * advance the string pointer.
3400 		 */
3401 		str += length;
3402 
3403 		/*
3404 		 * Copy all the characters from the variable value straight
3405 		 * into the new string.
3406 		 */
3407 		length = strlen(val);
3408 		Buf_AddBytes(buf, length, (Byte *)val);
3409 		trailingBslash = length > 0 && val[length - 1] == '\\';
3410 		if (doFree) {
3411 		    free(val);
3412 		}
3413 	    }
3414 	}
3415     }
3416 
3417     Buf_AddByte(buf, '\0');
3418     val = (char *)Buf_GetAll(buf, NULL);
3419     Buf_Destroy(buf, FALSE);
3420     return (val);
3421 }
3422 
3423 /*-
3424  *-----------------------------------------------------------------------
3425  * Var_GetTail --
3426  *	Return the tail from each of a list of words. Used to set the
3427  *	System V local variables.
3428  *
3429  * Input:
3430  *	file		Filename to modify
3431  *
3432  * Results:
3433  *	The resulting string.
3434  *
3435  * Side Effects:
3436  *	None.
3437  *
3438  *-----------------------------------------------------------------------
3439  */
3440 #if 0
3441 char *
3442 Var_GetTail(char *file)
3443 {
3444     return(VarModify(file, VarTail, (ClientData)0));
3445 }
3446 
3447 /*-
3448  *-----------------------------------------------------------------------
3449  * Var_GetHead --
3450  *	Find the leading components of a (list of) filename(s).
3451  *	XXX: VarHead does not replace foo by ., as (sun) System V make
3452  *	does.
3453  *
3454  * Input:
3455  *	file		Filename to manipulate
3456  *
3457  * Results:
3458  *	The leading components.
3459  *
3460  * Side Effects:
3461  *	None.
3462  *
3463  *-----------------------------------------------------------------------
3464  */
3465 char *
3466 Var_GetHead(char *file)
3467 {
3468     return(VarModify(file, VarHead, (ClientData)0));
3469 }
3470 #endif
3471 
3472 /*-
3473  *-----------------------------------------------------------------------
3474  * Var_Init --
3475  *	Initialize the module
3476  *
3477  * Results:
3478  *	None
3479  *
3480  * Side Effects:
3481  *	The VAR_CMD and VAR_GLOBAL contexts are created
3482  *-----------------------------------------------------------------------
3483  */
3484 void
3485 Var_Init(void)
3486 {
3487     VAR_GLOBAL = Targ_NewGN("Global");
3488     VAR_CMD = Targ_NewGN("Command");
3489 
3490 }
3491 
3492 
3493 void
3494 Var_End(void)
3495 {
3496 }
3497 
3498 
3499 /****************** PRINT DEBUGGING INFO *****************/
3500 static void
3501 VarPrintVar(ClientData vp)
3502 {
3503     Var    *v = (Var *)vp;
3504     printf("%-16s = %s\n", v->name, (char *)Buf_GetAll(v->val, NULL));
3505 }
3506 
3507 /*-
3508  *-----------------------------------------------------------------------
3509  * Var_Dump --
3510  *	print all variables in a context
3511  *-----------------------------------------------------------------------
3512  */
3513 void
3514 Var_Dump(GNode *ctxt)
3515 {
3516     Hash_Search search;
3517     Hash_Entry *h;
3518 
3519     for (h = Hash_EnumFirst(&ctxt->context, &search);
3520 	 h != NULL;
3521 	 h = Hash_EnumNext(&search)) {
3522 	    VarPrintVar(Hash_GetValue(h));
3523     }
3524 }
3525