xref: /netbsd-src/usr.bin/make/var.c (revision 89c5a767f8fc7a4633b2d409966e2becbb98ff92)
1 /*	$NetBSD: var.c,v 1.37 1999/09/15 22:51:05 sommerfeld Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1989 by Berkeley Softworks
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Adam de Boor.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #ifdef MAKE_BOOTSTRAP
42 static char rcsid[] = "$NetBSD: var.c,v 1.37 1999/09/15 22:51:05 sommerfeld Exp $";
43 #else
44 #include <sys/cdefs.h>
45 #ifndef lint
46 #if 0
47 static char sccsid[] = "@(#)var.c	8.3 (Berkeley) 3/19/94";
48 #else
49 __RCSID("$NetBSD: var.c,v 1.37 1999/09/15 22:51:05 sommerfeld Exp $");
50 #endif
51 #endif /* not lint */
52 #endif
53 
54 /*-
55  * var.c --
56  *	Variable-handling functions
57  *
58  * Interface:
59  *	Var_Set	  	    Set the value of a variable in the given
60  *	    	  	    context. The variable is created if it doesn't
61  *	    	  	    yet exist. The value and variable name need not
62  *	    	  	    be preserved.
63  *
64  *	Var_Append	    Append more characters to an existing variable
65  *	    	  	    in the given context. The variable needn't
66  *	    	  	    exist already -- it will be created if it doesn't.
67  *	    	  	    A space is placed between the old value and the
68  *	    	  	    new one.
69  *
70  *	Var_Exists	    See if a variable exists.
71  *
72  *	Var_Value 	    Return the value of a variable in a context or
73  *	    	  	    NULL if the variable is undefined.
74  *
75  *	Var_Subst 	    Substitute named variable, or all variables if
76  *			    NULL in a string using
77  *	    	  	    the given context as the top-most one. If the
78  *	    	  	    third argument is non-zero, Parse_Error is
79  *	    	  	    called if any variables are undefined.
80  *
81  *	Var_Parse 	    Parse a variable expansion from a string and
82  *	    	  	    return the result and the number of characters
83  *	    	  	    consumed.
84  *
85  *	Var_Delete	    Delete a variable in a context.
86  *
87  *	Var_Init  	    Initialize this module.
88  *
89  * Debugging:
90  *	Var_Dump  	    Print out all variables defined in the given
91  *	    	  	    context.
92  *
93  * XXX: There's a lot of duplication in these functions.
94  */
95 
96 #include    <ctype.h>
97 #ifndef NO_REGEX
98 #include    <sys/types.h>
99 #include    <regex.h>
100 #endif
101 #include    <stdlib.h>
102 #include    "make.h"
103 #include    "buf.h"
104 
105 /*
106  * This is a harmless return value for Var_Parse that can be used by Var_Subst
107  * to determine if there was an error in parsing -- easier than returning
108  * a flag, as things outside this module don't give a hoot.
109  */
110 char 	var_Error[] = "";
111 
112 /*
113  * Similar to var_Error, but returned when the 'err' flag for Var_Parse is
114  * set false. Why not just use a constant? Well, gcc likes to condense
115  * identical string instances...
116  */
117 static char	varNoError[] = "";
118 
119 /*
120  * Internally, variables are contained in four different contexts.
121  *	1) the environment. They may not be changed. If an environment
122  *	    variable is appended-to, the result is placed in the global
123  *	    context.
124  *	2) the global context. Variables set in the Makefile are located in
125  *	    the global context. It is the penultimate context searched when
126  *	    substituting.
127  *	3) the command-line context. All variables set on the command line
128  *	   are placed in this context. They are UNALTERABLE once placed here.
129  *	4) the local context. Each target has associated with it a context
130  *	   list. On this list are located the structures describing such
131  *	   local variables as $(@) and $(*)
132  * The four contexts are searched in the reverse order from which they are
133  * listed.
134  */
135 GNode          *VAR_GLOBAL;   /* variables from the makefile */
136 GNode          *VAR_CMD;      /* variables defined on the command-line */
137 
138 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
139 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
140 #define FIND_ENV  	0x4   /* look in the environment also */
141 
142 typedef struct Var {
143     char          *name;	/* the variable's name */
144     Buffer	  val;	    	/* its value */
145     int	    	  flags;    	/* miscellaneous status flags */
146 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
147 				     * Used to avoid recursion */
148 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
149 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
150 				     * should be destroyed when done with
151 				     * it. Used by Var_Parse for undefined,
152 				     * modified variables */
153 }  Var;
154 
155 
156 /* Var*Pattern flags */
157 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
158 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
159 #define VAR_SUB_MATCHED	0x04	/* There was a match */
160 #define VAR_MATCH_START	0x08	/* Match at start of word */
161 #define VAR_MATCH_END	0x10	/* Match at end of word */
162 
163 typedef struct {
164     char    	  *lhs;	    /* String to match */
165     int	    	   leftLen; /* Length of string */
166     char    	  *rhs;	    /* Replacement string (w/ &'s removed) */
167     int	    	  rightLen; /* Length of replacement */
168     int	    	  flags;
169 } VarPattern;
170 
171 #ifndef NO_REGEX
172 typedef struct {
173     regex_t	   re;
174     int		   nsub;
175     regmatch_t 	  *matches;
176     char 	  *replace;
177     int		   flags;
178 } VarREPattern;
179 #endif
180 
181 static Var *VarFind __P((char *, GNode *, int));
182 static void VarAdd __P((char *, char *, GNode *));
183 static Boolean VarHead __P((char *, Boolean, Buffer, ClientData));
184 static Boolean VarTail __P((char *, Boolean, Buffer, ClientData));
185 static Boolean VarSuffix __P((char *, Boolean, Buffer, ClientData));
186 static Boolean VarRoot __P((char *, Boolean, Buffer, ClientData));
187 static Boolean VarMatch __P((char *, Boolean, Buffer, ClientData));
188 #ifdef SYSVVARSUB
189 static Boolean VarSYSVMatch __P((char *, Boolean, Buffer, ClientData));
190 #endif
191 static Boolean VarNoMatch __P((char *, Boolean, Buffer, ClientData));
192 #ifndef NO_REGEX
193 static void VarREError __P((int, regex_t *, const char *));
194 static Boolean VarRESubstitute __P((char *, Boolean, Buffer, ClientData));
195 #endif
196 static Boolean VarSubstitute __P((char *, Boolean, Buffer, ClientData));
197 static char *VarGetPattern __P((GNode *, int, char **, int, int *, int *,
198 				VarPattern *));
199 static char *VarQuote __P((char *));
200 static char *VarModify __P((char *, Boolean (*)(char *, Boolean, Buffer,
201 						ClientData),
202 			    ClientData));
203 static char *VarSort __P((char *));
204 static int VarWordCompare __P((const void *, const void *));
205 static void VarPrintVar __P((ClientData));
206 
207 /*-
208  *-----------------------------------------------------------------------
209  * VarFind --
210  *	Find the given variable in the given context and any other contexts
211  *	indicated.
212  *
213  * Results:
214  *	A pointer to the structure describing the desired variable or
215  *	NIL if the variable does not exist.
216  *
217  * Side Effects:
218  *	None
219  *-----------------------------------------------------------------------
220  */
221 static Var *
222 VarFind (name, ctxt, flags)
223     char           	*name;	/* name to find */
224     GNode          	*ctxt;	/* context in which to find it */
225     int             	flags;	/* FIND_GLOBAL set means to look in the
226 				 * VAR_GLOBAL context as well.
227 				 * FIND_CMD set means to look in the VAR_CMD
228 				 * context also.
229 				 * FIND_ENV set means to look in the
230 				 * environment */
231 {
232     Hash_Entry         	*var;
233     Var		  	*v;
234 
235 	/*
236 	 * If the variable name begins with a '.', it could very well be one of
237 	 * the local ones.  We check the name against all the local variables
238 	 * and substitute the short version in for 'name' if it matches one of
239 	 * them.
240 	 */
241 	if (*name == '.' && isupper((unsigned char) name[1]))
242 		switch (name[1]) {
243 		case 'A':
244 			if (!strcmp(name, ".ALLSRC"))
245 				name = ALLSRC;
246 			if (!strcmp(name, ".ARCHIVE"))
247 				name = ARCHIVE;
248 			break;
249 		case 'I':
250 			if (!strcmp(name, ".IMPSRC"))
251 				name = IMPSRC;
252 			break;
253 		case 'M':
254 			if (!strcmp(name, ".MEMBER"))
255 				name = MEMBER;
256 			break;
257 		case 'O':
258 			if (!strcmp(name, ".OODATE"))
259 				name = OODATE;
260 			break;
261 		case 'P':
262 			if (!strcmp(name, ".PREFIX"))
263 				name = PREFIX;
264 			break;
265 		case 'T':
266 			if (!strcmp(name, ".TARGET"))
267 				name = TARGET;
268 			break;
269 		}
270     /*
271      * First look for the variable in the given context. If it's not there,
272      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
273      * depending on the FIND_* flags in 'flags'
274      */
275     var = Hash_FindEntry (&ctxt->context, name);
276 
277     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
278 	var = Hash_FindEntry (&VAR_CMD->context, name);
279     }
280     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
281 	(ctxt != VAR_GLOBAL))
282     {
283 	var = Hash_FindEntry (&VAR_GLOBAL->context, name);
284     }
285     if ((var == NULL) && (flags & FIND_ENV)) {
286 	char *env;
287 
288 	if ((env = getenv (name)) != NULL) {
289 	    int	  	len;
290 
291 	    v = (Var *) emalloc(sizeof(Var));
292 	    v->name = estrdup(name);
293 
294 	    len = strlen(env);
295 
296 	    v->val = Buf_Init(len);
297 	    Buf_AddBytes(v->val, len, (Byte *)env);
298 
299 	    v->flags = VAR_FROM_ENV;
300 	    return (v);
301 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
302 		   (ctxt != VAR_GLOBAL))
303 	{
304 	    var = Hash_FindEntry (&VAR_GLOBAL->context, name);
305 	    if (var == NULL) {
306 		return ((Var *) NIL);
307 	    } else {
308 		return ((Var *)Hash_GetValue(var));
309 	    }
310 	} else {
311 	    return((Var *)NIL);
312 	}
313     } else if (var == NULL) {
314 	return ((Var *) NIL);
315     } else {
316 	return ((Var *) Hash_GetValue(var));
317     }
318 }
319 
320 /*-
321  *-----------------------------------------------------------------------
322  * VarAdd  --
323  *	Add a new variable of name name and value val to the given context
324  *
325  * Results:
326  *	None
327  *
328  * Side Effects:
329  *	The new variable is placed at the front of the given context
330  *	The name and val arguments are duplicated so they may
331  *	safely be freed.
332  *-----------------------------------------------------------------------
333  */
334 static void
335 VarAdd (name, val, ctxt)
336     char           *name;	/* name of variable to add */
337     char           *val;	/* value to set it to */
338     GNode          *ctxt;	/* context in which to set it */
339 {
340     register Var   *v;
341     int	    	  len;
342     Hash_Entry      *h;
343 
344     v = (Var *) emalloc (sizeof (Var));
345 
346     len = val ? strlen(val) : 0;
347     v->val = Buf_Init(len+1);
348     Buf_AddBytes(v->val, len, (Byte *)val);
349 
350     v->flags = 0;
351 
352     h = Hash_CreateEntry (&ctxt->context, name, NULL);
353     Hash_SetValue(h, v);
354     v->name = h->name;
355     if (DEBUG(VAR)) {
356 	printf("%s:%s = %s\n", ctxt->name, name, val);
357     }
358 }
359 
360 /*-
361  *-----------------------------------------------------------------------
362  * Var_Delete --
363  *	Remove a variable from a context.
364  *
365  * Results:
366  *	None.
367  *
368  * Side Effects:
369  *	The Var structure is removed and freed.
370  *
371  *-----------------------------------------------------------------------
372  */
373 void
374 Var_Delete(name, ctxt)
375     char    	  *name;
376     GNode	  *ctxt;
377 {
378     Hash_Entry 	  *ln;
379 
380     if (DEBUG(VAR)) {
381 	printf("%s:delete %s\n", ctxt->name, name);
382     }
383     ln = Hash_FindEntry(&ctxt->context, name);
384     if (ln != NULL) {
385 	register Var 	  *v;
386 
387 	v = (Var *)Hash_GetValue(ln);
388 	if (v->name != ln->name)
389 		free(v->name);
390 	Hash_DeleteEntry(&ctxt->context, ln);
391 	Buf_Destroy(v->val, TRUE);
392 	free((Address) v);
393     }
394 }
395 
396 /*-
397  *-----------------------------------------------------------------------
398  * Var_Set --
399  *	Set the variable name to the value val in the given context.
400  *
401  * Results:
402  *	None.
403  *
404  * Side Effects:
405  *	If the variable doesn't yet exist, a new record is created for it.
406  *	Else the old value is freed and the new one stuck in its place
407  *
408  * Notes:
409  *	The variable is searched for only in its context before being
410  *	created in that context. I.e. if the context is VAR_GLOBAL,
411  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
412  *	VAR_CMD->context is searched. This is done to avoid the literally
413  *	thousands of unnecessary strcmp's that used to be done to
414  *	set, say, $(@) or $(<).
415  *-----------------------------------------------------------------------
416  */
417 void
418 Var_Set (name, val, ctxt)
419     char           *name;	/* name of variable to set */
420     char           *val;	/* value to give to the variable */
421     GNode          *ctxt;	/* context in which to set it */
422 {
423     register Var   *v;
424 
425     /*
426      * We only look for a variable in the given context since anything set
427      * here will override anything in a lower context, so there's not much
428      * point in searching them all just to save a bit of memory...
429      */
430     v = VarFind (name, ctxt, 0);
431     if (v == (Var *) NIL) {
432 	VarAdd (name, val, ctxt);
433     } else {
434 	Buf_Discard(v->val, Buf_Size(v->val));
435 	Buf_AddBytes(v->val, strlen(val), (Byte *)val);
436 
437 	if (DEBUG(VAR)) {
438 	    printf("%s:%s = %s\n", ctxt->name, name, val);
439 	}
440     }
441     /*
442      * Any variables given on the command line are automatically exported
443      * to the environment (as per POSIX standard)
444      */
445     if (ctxt == VAR_CMD) {
446 	setenv(name, val, 1);
447     }
448 }
449 
450 /*-
451  *-----------------------------------------------------------------------
452  * Var_Append --
453  *	The variable of the given name has the given value appended to it in
454  *	the given context.
455  *
456  * Results:
457  *	None
458  *
459  * Side Effects:
460  *	If the variable doesn't exist, it is created. Else the strings
461  *	are concatenated (with a space in between).
462  *
463  * Notes:
464  *	Only if the variable is being sought in the global context is the
465  *	environment searched.
466  *	XXX: Knows its calling circumstances in that if called with ctxt
467  *	an actual target, it will only search that context since only
468  *	a local variable could be being appended to. This is actually
469  *	a big win and must be tolerated.
470  *-----------------------------------------------------------------------
471  */
472 void
473 Var_Append (name, val, ctxt)
474     char           *name;	/* Name of variable to modify */
475     char           *val;	/* String to append to it */
476     GNode          *ctxt;	/* Context in which this should occur */
477 {
478     register Var   *v;
479     Hash_Entry	   *h;
480 
481     v = VarFind (name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
482 
483     if (v == (Var *) NIL) {
484 	VarAdd (name, val, ctxt);
485     } else {
486 	Buf_AddByte(v->val, (Byte)' ');
487 	Buf_AddBytes(v->val, strlen(val), (Byte *)val);
488 
489 	if (DEBUG(VAR)) {
490 	    printf("%s:%s = %s\n", ctxt->name, name,
491 		   (char *) Buf_GetAll(v->val, (int *)NULL));
492 	}
493 
494 	if (v->flags & VAR_FROM_ENV) {
495 	    /*
496 	     * If the original variable came from the environment, we
497 	     * have to install it in the global context (we could place
498 	     * it in the environment, but then we should provide a way to
499 	     * export other variables...)
500 	     */
501 	    v->flags &= ~VAR_FROM_ENV;
502 	    h = Hash_CreateEntry (&ctxt->context, name, NULL);
503 	    Hash_SetValue(h, v);
504 	}
505     }
506 }
507 
508 /*-
509  *-----------------------------------------------------------------------
510  * Var_Exists --
511  *	See if the given variable exists.
512  *
513  * Results:
514  *	TRUE if it does, FALSE if it doesn't
515  *
516  * Side Effects:
517  *	None.
518  *
519  *-----------------------------------------------------------------------
520  */
521 Boolean
522 Var_Exists(name, ctxt)
523     char	  *name;    	/* Variable to find */
524     GNode	  *ctxt;    	/* Context in which to start search */
525 {
526     Var	    	  *v;
527 
528     v = VarFind(name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
529 
530     if (v == (Var *)NIL) {
531 	return(FALSE);
532     } else if (v->flags & VAR_FROM_ENV) {
533 	free(v->name);
534 	Buf_Destroy(v->val, TRUE);
535 	free((char *)v);
536     }
537     return(TRUE);
538 }
539 
540 /*-
541  *-----------------------------------------------------------------------
542  * Var_Value --
543  *	Return the value of the named variable in the given context
544  *
545  * Results:
546  *	The value if the variable exists, NULL if it doesn't
547  *
548  * Side Effects:
549  *	None
550  *-----------------------------------------------------------------------
551  */
552 char *
553 Var_Value (name, ctxt, frp)
554     char           *name;	/* name to find */
555     GNode          *ctxt;	/* context in which to search for it */
556     char	   **frp;
557 {
558     Var            *v;
559 
560     v = VarFind (name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
561     *frp = NULL;
562     if (v != (Var *) NIL) {
563 	char *p = ((char *)Buf_GetAll(v->val, (int *)NULL));
564 	if (v->flags & VAR_FROM_ENV) {
565 	    free(v->name);
566 	    Buf_Destroy(v->val, FALSE);
567 	    free((Address) v);
568 	    *frp = p;
569 	}
570 	return p;
571     } else {
572 	return ((char *) NULL);
573     }
574 }
575 
576 /*-
577  *-----------------------------------------------------------------------
578  * VarHead --
579  *	Remove the tail of the given word and place the result in the given
580  *	buffer.
581  *
582  * Results:
583  *	TRUE if characters were added to the buffer (a space needs to be
584  *	added to the buffer before the next word).
585  *
586  * Side Effects:
587  *	The trimmed word is added to the buffer.
588  *
589  *-----------------------------------------------------------------------
590  */
591 static Boolean
592 VarHead (word, addSpace, buf, dummy)
593     char    	  *word;    	/* Word to trim */
594     Boolean 	  addSpace; 	/* True if need to add a space to the buffer
595 				 * before sticking in the head */
596     Buffer  	  buf;	    	/* Buffer in which to store it */
597     ClientData	  dummy;
598 {
599     register char *slash;
600 
601     slash = strrchr (word, '/');
602     if (slash != (char *)NULL) {
603 	if (addSpace) {
604 	    Buf_AddByte (buf, (Byte)' ');
605 	}
606 	*slash = '\0';
607 	Buf_AddBytes (buf, strlen (word), (Byte *)word);
608 	*slash = '/';
609 	return (TRUE);
610     } else {
611 	/*
612 	 * If no directory part, give . (q.v. the POSIX standard)
613 	 */
614 	if (addSpace) {
615 	    Buf_AddBytes(buf, 2, (Byte *)" .");
616 	} else {
617 	    Buf_AddByte(buf, (Byte)'.');
618 	}
619     }
620     return(dummy ? TRUE : TRUE);
621 }
622 
623 /*-
624  *-----------------------------------------------------------------------
625  * VarTail --
626  *	Remove the head of the given word and place the result in the given
627  *	buffer.
628  *
629  * Results:
630  *	TRUE if characters were added to the buffer (a space needs to be
631  *	added to the buffer before the next word).
632  *
633  * Side Effects:
634  *	The trimmed word is added to the buffer.
635  *
636  *-----------------------------------------------------------------------
637  */
638 static Boolean
639 VarTail (word, addSpace, buf, dummy)
640     char    	  *word;    	/* Word to trim */
641     Boolean 	  addSpace; 	/* TRUE if need to stick a space in the
642 				 * buffer before adding the tail */
643     Buffer  	  buf;	    	/* Buffer in which to store it */
644     ClientData	  dummy;
645 {
646     register char *slash;
647 
648     if (addSpace) {
649 	Buf_AddByte (buf, (Byte)' ');
650     }
651 
652     slash = strrchr (word, '/');
653     if (slash != (char *)NULL) {
654 	*slash++ = '\0';
655 	Buf_AddBytes (buf, strlen(slash), (Byte *)slash);
656 	slash[-1] = '/';
657     } else {
658 	Buf_AddBytes (buf, strlen(word), (Byte *)word);
659     }
660     return (dummy ? TRUE : TRUE);
661 }
662 
663 /*-
664  *-----------------------------------------------------------------------
665  * VarSuffix --
666  *	Place the suffix of the given word in the given buffer.
667  *
668  * Results:
669  *	TRUE if characters were added to the buffer (a space needs to be
670  *	added to the buffer before the next word).
671  *
672  * Side Effects:
673  *	The suffix from the word is placed in the buffer.
674  *
675  *-----------------------------------------------------------------------
676  */
677 static Boolean
678 VarSuffix (word, addSpace, buf, dummy)
679     char    	  *word;    	/* Word to trim */
680     Boolean 	  addSpace; 	/* TRUE if need to add a space before placing
681 				 * the suffix in the buffer */
682     Buffer  	  buf;	    	/* Buffer in which to store it */
683     ClientData	  dummy;
684 {
685     register char *dot;
686 
687     dot = strrchr (word, '.');
688     if (dot != (char *)NULL) {
689 	if (addSpace) {
690 	    Buf_AddByte (buf, (Byte)' ');
691 	}
692 	*dot++ = '\0';
693 	Buf_AddBytes (buf, strlen (dot), (Byte *)dot);
694 	dot[-1] = '.';
695 	addSpace = TRUE;
696     }
697     return (dummy ? addSpace : addSpace);
698 }
699 
700 /*-
701  *-----------------------------------------------------------------------
702  * VarRoot --
703  *	Remove the suffix of the given word and place the result in the
704  *	buffer.
705  *
706  * Results:
707  *	TRUE if characters were added to the buffer (a space needs to be
708  *	added to the buffer before the next word).
709  *
710  * Side Effects:
711  *	The trimmed word is added to the buffer.
712  *
713  *-----------------------------------------------------------------------
714  */
715 static Boolean
716 VarRoot (word, addSpace, buf, dummy)
717     char    	  *word;    	/* Word to trim */
718     Boolean 	  addSpace; 	/* TRUE if need to add a space to the buffer
719 				 * before placing the root in it */
720     Buffer  	  buf;	    	/* Buffer in which to store it */
721     ClientData	  dummy;
722 {
723     register char *dot;
724 
725     if (addSpace) {
726 	Buf_AddByte (buf, (Byte)' ');
727     }
728 
729     dot = strrchr (word, '.');
730     if (dot != (char *)NULL) {
731 	*dot = '\0';
732 	Buf_AddBytes (buf, strlen (word), (Byte *)word);
733 	*dot = '.';
734     } else {
735 	Buf_AddBytes (buf, strlen(word), (Byte *)word);
736     }
737     return (dummy ? TRUE : TRUE);
738 }
739 
740 /*-
741  *-----------------------------------------------------------------------
742  * VarMatch --
743  *	Place the word in the buffer if it matches the given pattern.
744  *	Callback function for VarModify to implement the :M modifier.
745  *
746  * Results:
747  *	TRUE if a space should be placed in the buffer before the next
748  *	word.
749  *
750  * Side Effects:
751  *	The word may be copied to the buffer.
752  *
753  *-----------------------------------------------------------------------
754  */
755 static Boolean
756 VarMatch (word, addSpace, buf, pattern)
757     char    	  *word;    	/* Word to examine */
758     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
759 				 * buffer before adding the word, if it
760 				 * matches */
761     Buffer  	  buf;	    	/* Buffer in which to store it */
762     ClientData    pattern; 	/* Pattern the word must match */
763 {
764     if (Str_Match(word, (char *) pattern)) {
765 	if (addSpace) {
766 	    Buf_AddByte(buf, (Byte)' ');
767 	}
768 	addSpace = TRUE;
769 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
770     }
771     return(addSpace);
772 }
773 
774 #ifdef SYSVVARSUB
775 /*-
776  *-----------------------------------------------------------------------
777  * VarSYSVMatch --
778  *	Place the word in the buffer if it matches the given pattern.
779  *	Callback function for VarModify to implement the System V %
780  *	modifiers.
781  *
782  * Results:
783  *	TRUE if a space should be placed in the buffer before the next
784  *	word.
785  *
786  * Side Effects:
787  *	The word may be copied to the buffer.
788  *
789  *-----------------------------------------------------------------------
790  */
791 static Boolean
792 VarSYSVMatch (word, addSpace, buf, patp)
793     char    	  *word;    	/* Word to examine */
794     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
795 				 * buffer before adding the word, if it
796 				 * matches */
797     Buffer  	  buf;	    	/* Buffer in which to store it */
798     ClientData 	  patp; 	/* Pattern the word must match */
799 {
800     int len;
801     char *ptr;
802     VarPattern 	  *pat = (VarPattern *) patp;
803 
804     if (addSpace)
805 	Buf_AddByte(buf, (Byte)' ');
806 
807     addSpace = TRUE;
808 
809     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL)
810 	Str_SYSVSubst(buf, pat->rhs, ptr, len);
811     else
812 	Buf_AddBytes(buf, strlen(word), (Byte *) word);
813 
814     return(addSpace);
815 }
816 #endif
817 
818 
819 /*-
820  *-----------------------------------------------------------------------
821  * VarNoMatch --
822  *	Place the word in the buffer if it doesn't match the given pattern.
823  *	Callback function for VarModify to implement the :N modifier.
824  *
825  * Results:
826  *	TRUE if a space should be placed in the buffer before the next
827  *	word.
828  *
829  * Side Effects:
830  *	The word may be copied to the buffer.
831  *
832  *-----------------------------------------------------------------------
833  */
834 static Boolean
835 VarNoMatch (word, addSpace, buf, pattern)
836     char    	  *word;    	/* Word to examine */
837     Boolean 	  addSpace; 	/* TRUE if need to add a space to the
838 				 * buffer before adding the word, if it
839 				 * matches */
840     Buffer  	  buf;	    	/* Buffer in which to store it */
841     ClientData    pattern; 	/* Pattern the word must match */
842 {
843     if (!Str_Match(word, (char *) pattern)) {
844 	if (addSpace) {
845 	    Buf_AddByte(buf, (Byte)' ');
846 	}
847 	addSpace = TRUE;
848 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
849     }
850     return(addSpace);
851 }
852 
853 
854 /*-
855  *-----------------------------------------------------------------------
856  * VarSubstitute --
857  *	Perform a string-substitution on the given word, placing the
858  *	result in the passed buffer.
859  *
860  * Results:
861  *	TRUE if a space is needed before more characters are added.
862  *
863  * Side Effects:
864  *	None.
865  *
866  *-----------------------------------------------------------------------
867  */
868 static Boolean
869 VarSubstitute (word, addSpace, buf, patternp)
870     char    	  	*word;	    /* Word to modify */
871     Boolean 	  	addSpace;   /* True if space should be added before
872 				     * other characters */
873     Buffer  	  	buf;	    /* Buffer for result */
874     ClientData	        patternp;   /* Pattern for substitution */
875 {
876     register int  	wordLen;    /* Length of word */
877     register char 	*cp;	    /* General pointer */
878     VarPattern	*pattern = (VarPattern *) patternp;
879 
880     wordLen = strlen(word);
881     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
882 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
883 	/*
884 	 * Still substituting -- break it down into simple anchored cases
885 	 * and if none of them fits, perform the general substitution case.
886 	 */
887 	if ((pattern->flags & VAR_MATCH_START) &&
888 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
889 		/*
890 		 * Anchored at start and beginning of word matches pattern
891 		 */
892 		if ((pattern->flags & VAR_MATCH_END) &&
893 		    (wordLen == pattern->leftLen)) {
894 			/*
895 			 * Also anchored at end and matches to the end (word
896 			 * is same length as pattern) add space and rhs only
897 			 * if rhs is non-null.
898 			 */
899 			if (pattern->rightLen != 0) {
900 			    if (addSpace) {
901 				Buf_AddByte(buf, (Byte)' ');
902 			    }
903 			    addSpace = TRUE;
904 			    Buf_AddBytes(buf, pattern->rightLen,
905 					 (Byte *)pattern->rhs);
906 			}
907 			pattern->flags |= VAR_SUB_MATCHED;
908 		} else if (pattern->flags & VAR_MATCH_END) {
909 		    /*
910 		     * Doesn't match to end -- copy word wholesale
911 		     */
912 		    goto nosub;
913 		} else {
914 		    /*
915 		     * Matches at start but need to copy in trailing characters
916 		     */
917 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
918 			if (addSpace) {
919 			    Buf_AddByte(buf, (Byte)' ');
920 			}
921 			addSpace = TRUE;
922 		    }
923 		    Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
924 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
925 				 (Byte *)(word + pattern->leftLen));
926 		    pattern->flags |= VAR_SUB_MATCHED;
927 		}
928 	} else if (pattern->flags & VAR_MATCH_START) {
929 	    /*
930 	     * Had to match at start of word and didn't -- copy whole word.
931 	     */
932 	    goto nosub;
933 	} else if (pattern->flags & VAR_MATCH_END) {
934 	    /*
935 	     * Anchored at end, Find only place match could occur (leftLen
936 	     * characters from the end of the word) and see if it does. Note
937 	     * that because the $ will be left at the end of the lhs, we have
938 	     * to use strncmp.
939 	     */
940 	    cp = word + (wordLen - pattern->leftLen);
941 	    if ((cp >= word) &&
942 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
943 		/*
944 		 * Match found. If we will place characters in the buffer,
945 		 * add a space before hand as indicated by addSpace, then
946 		 * stuff in the initial, unmatched part of the word followed
947 		 * by the right-hand-side.
948 		 */
949 		if (((cp - word) + pattern->rightLen) != 0) {
950 		    if (addSpace) {
951 			Buf_AddByte(buf, (Byte)' ');
952 		    }
953 		    addSpace = TRUE;
954 		}
955 		Buf_AddBytes(buf, cp - word, (Byte *)word);
956 		Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
957 		pattern->flags |= VAR_SUB_MATCHED;
958 	    } else {
959 		/*
960 		 * Had to match at end and didn't. Copy entire word.
961 		 */
962 		goto nosub;
963 	    }
964 	} else {
965 	    /*
966 	     * Pattern is unanchored: search for the pattern in the word using
967 	     * String_FindSubstring, copying unmatched portions and the
968 	     * right-hand-side for each match found, handling non-global
969 	     * substitutions correctly, etc. When the loop is done, any
970 	     * remaining part of the word (word and wordLen are adjusted
971 	     * accordingly through the loop) is copied straight into the
972 	     * buffer.
973 	     * addSpace is set FALSE as soon as a space is added to the
974 	     * buffer.
975 	     */
976 	    register Boolean done;
977 	    int origSize;
978 
979 	    done = FALSE;
980 	    origSize = Buf_Size(buf);
981 	    while (!done) {
982 		cp = Str_FindSubstring(word, pattern->lhs);
983 		if (cp != (char *)NULL) {
984 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
985 			Buf_AddByte(buf, (Byte)' ');
986 			addSpace = FALSE;
987 		    }
988 		    Buf_AddBytes(buf, cp-word, (Byte *)word);
989 		    Buf_AddBytes(buf, pattern->rightLen, (Byte *)pattern->rhs);
990 		    wordLen -= (cp - word) + pattern->leftLen;
991 		    word = cp + pattern->leftLen;
992 		    if (wordLen == 0) {
993 			done = TRUE;
994 		    }
995 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
996 			done = TRUE;
997 		    }
998 		    pattern->flags |= VAR_SUB_MATCHED;
999 		} else {
1000 		    done = TRUE;
1001 		}
1002 	    }
1003 	    if (wordLen != 0) {
1004 		if (addSpace) {
1005 		    Buf_AddByte(buf, (Byte)' ');
1006 		}
1007 		Buf_AddBytes(buf, wordLen, (Byte *)word);
1008 	    }
1009 	    /*
1010 	     * If added characters to the buffer, need to add a space
1011 	     * before we add any more. If we didn't add any, just return
1012 	     * the previous value of addSpace.
1013 	     */
1014 	    return ((Buf_Size(buf) != origSize) || addSpace);
1015 	}
1016 	return (addSpace);
1017     }
1018  nosub:
1019     if (addSpace) {
1020 	Buf_AddByte(buf, (Byte)' ');
1021     }
1022     Buf_AddBytes(buf, wordLen, (Byte *)word);
1023     return(TRUE);
1024 }
1025 
1026 #ifndef NO_REGEX
1027 /*-
1028  *-----------------------------------------------------------------------
1029  * VarREError --
1030  *	Print the error caused by a regcomp or regexec call.
1031  *
1032  * Results:
1033  *	None.
1034  *
1035  * Side Effects:
1036  *	An error gets printed.
1037  *
1038  *-----------------------------------------------------------------------
1039  */
1040 static void
1041 VarREError(err, pat, str)
1042     int err;
1043     regex_t *pat;
1044     const char *str;
1045 {
1046     char *errbuf;
1047     int errlen;
1048 
1049     errlen = regerror(err, pat, 0, 0);
1050     errbuf = emalloc(errlen);
1051     regerror(err, pat, errbuf, errlen);
1052     Error("%s: %s", str, errbuf);
1053     free(errbuf);
1054 }
1055 
1056 
1057 /*-
1058  *-----------------------------------------------------------------------
1059  * VarRESubstitute --
1060  *	Perform a regex substitution on the given word, placing the
1061  *	result in the passed buffer.
1062  *
1063  * Results:
1064  *	TRUE if a space is needed before more characters are added.
1065  *
1066  * Side Effects:
1067  *	None.
1068  *
1069  *-----------------------------------------------------------------------
1070  */
1071 static Boolean
1072 VarRESubstitute(word, addSpace, buf, patternp)
1073     char *word;
1074     Boolean addSpace;
1075     Buffer buf;
1076     ClientData patternp;
1077 {
1078     VarREPattern *pat;
1079     int xrv;
1080     char *wp;
1081     char *rp;
1082     int added;
1083     int flags = 0;
1084 
1085 #define MAYBE_ADD_SPACE()		\
1086 	if (addSpace && !added)		\
1087 	    Buf_AddByte(buf, ' ');	\
1088 	added = 1
1089 
1090     added = 0;
1091     wp = word;
1092     pat = patternp;
1093 
1094     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1095 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1096 	xrv = REG_NOMATCH;
1097     else {
1098     tryagain:
1099 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1100     }
1101 
1102     switch (xrv) {
1103     case 0:
1104 	pat->flags |= VAR_SUB_MATCHED;
1105 	if (pat->matches[0].rm_so > 0) {
1106 	    MAYBE_ADD_SPACE();
1107 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1108 	}
1109 
1110 	for (rp = pat->replace; *rp; rp++) {
1111 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1112 		MAYBE_ADD_SPACE();
1113 		Buf_AddByte(buf,rp[1]);
1114 		rp++;
1115 	    }
1116 	    else if ((*rp == '&') ||
1117 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1118 		int n;
1119 		char *subbuf;
1120 		int sublen;
1121 		char errstr[3];
1122 
1123 		if (*rp == '&') {
1124 		    n = 0;
1125 		    errstr[0] = '&';
1126 		    errstr[1] = '\0';
1127 		} else {
1128 		    n = rp[1] - '0';
1129 		    errstr[0] = '\\';
1130 		    errstr[1] = rp[1];
1131 		    errstr[2] = '\0';
1132 		    rp++;
1133 		}
1134 
1135 		if (n > pat->nsub) {
1136 		    Error("No subexpression %s", &errstr[0]);
1137 		    subbuf = "";
1138 		    sublen = 0;
1139 		} else if ((pat->matches[n].rm_so == -1) &&
1140 			   (pat->matches[n].rm_eo == -1)) {
1141 		    Error("No match for subexpression %s", &errstr[0]);
1142 		    subbuf = "";
1143 		    sublen = 0;
1144 	        } else {
1145 		    subbuf = wp + pat->matches[n].rm_so;
1146 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1147 		}
1148 
1149 		if (sublen > 0) {
1150 		    MAYBE_ADD_SPACE();
1151 		    Buf_AddBytes(buf, sublen, subbuf);
1152 		}
1153 	    } else {
1154 		MAYBE_ADD_SPACE();
1155 		Buf_AddByte(buf, *rp);
1156 	    }
1157 	}
1158 	wp += pat->matches[0].rm_eo;
1159 	if (pat->flags & VAR_SUB_GLOBAL) {
1160 	    flags |= REG_NOTBOL;
1161 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1162 		MAYBE_ADD_SPACE();
1163 		Buf_AddByte(buf, *wp);
1164 		wp++;
1165 
1166 	    }
1167 	    if (*wp)
1168 		goto tryagain;
1169 	}
1170 	if (*wp) {
1171 	    MAYBE_ADD_SPACE();
1172 	    Buf_AddBytes(buf, strlen(wp), wp);
1173 	}
1174 	break;
1175     default:
1176 	VarREError(xrv, &pat->re, "Unexpected regex error");
1177        /* fall through */
1178     case REG_NOMATCH:
1179 	if (*wp) {
1180 	    MAYBE_ADD_SPACE();
1181 	    Buf_AddBytes(buf,strlen(wp),wp);
1182 	}
1183 	break;
1184     }
1185     return(addSpace||added);
1186 }
1187 #endif
1188 
1189 
1190 /*-
1191  *-----------------------------------------------------------------------
1192  * VarModify --
1193  *	Modify each of the words of the passed string using the given
1194  *	function. Used to implement all modifiers.
1195  *
1196  * Results:
1197  *	A string of all the words modified appropriately.
1198  *
1199  * Side Effects:
1200  *	None.
1201  *
1202  *-----------------------------------------------------------------------
1203  */
1204 static char *
1205 VarModify (str, modProc, datum)
1206     char    	  *str;	    	    /* String whose words should be trimmed */
1207 				    /* Function to use to modify them */
1208     Boolean    	  (*modProc) __P((char *, Boolean, Buffer, ClientData));
1209     ClientData	  datum;    	    /* Datum to pass it */
1210 {
1211     Buffer  	  buf;	    	    /* Buffer for the new string */
1212     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1213 				     * buffer before adding the trimmed
1214 				     * word */
1215     char **av;			    /* word list [first word does not count] */
1216     char *as;			    /* word list memory */
1217     int ac, i;
1218 
1219     buf = Buf_Init (0);
1220     addSpace = FALSE;
1221 
1222     av = brk_string(str, &ac, FALSE, &as);
1223 
1224     for (i = 0; i < ac; i++)
1225 	addSpace = (*modProc)(av[i], addSpace, buf, datum);
1226 
1227     free(as);
1228     free(av);
1229 
1230     Buf_AddByte (buf, '\0');
1231     str = (char *)Buf_GetAll (buf, (int *)NULL);
1232     Buf_Destroy (buf, FALSE);
1233     return (str);
1234 }
1235 
1236 
1237 static int
1238 VarWordCompare(a, b)
1239 	const void *a;
1240 	const void *b;
1241 {
1242 	int r = strcmp(*(char **)a, *(char **)b);
1243 	return r;
1244 }
1245 
1246 /*-
1247  *-----------------------------------------------------------------------
1248  * VarSort --
1249  *	Sort the words in the string.
1250  *
1251  * Results:
1252  *	A string containing the words sorted
1253  *
1254  * Side Effects:
1255  *	None.
1256  *
1257  *-----------------------------------------------------------------------
1258  */
1259 static char *
1260 VarSort (str)
1261     char    	  *str;	    	    /* String whose words should be sorted */
1262 				    /* Function to use to modify them */
1263 {
1264     Buffer  	  buf;	    	    /* Buffer for the new string */
1265     char **av;			    /* word list [first word does not count] */
1266     char *as;			    /* word list memory */
1267     int ac, i;
1268 
1269     buf = Buf_Init (0);
1270 
1271     av = brk_string(str, &ac, FALSE, &as);
1272 
1273     if (ac > 0)
1274 	qsort(av, ac, sizeof(char *), VarWordCompare);
1275 
1276     for (i = 0; i < ac; i++) {
1277 	Buf_AddBytes(buf, strlen(av[i]), (Byte *) av[i]);
1278 	if (i != ac - 1)
1279 	    Buf_AddByte (buf, ' ');
1280     }
1281 
1282     free(as);
1283     free(av);
1284 
1285     Buf_AddByte (buf, '\0');
1286     str = (char *)Buf_GetAll (buf, (int *)NULL);
1287     Buf_Destroy (buf, FALSE);
1288     return (str);
1289 }
1290 
1291 
1292 /*-
1293  *-----------------------------------------------------------------------
1294  * VarGetPattern --
1295  *	Pass through the tstr looking for 1) escaped delimiters,
1296  *	'$'s and backslashes (place the escaped character in
1297  *	uninterpreted) and 2) unescaped $'s that aren't before
1298  *	the delimiter (expand the variable substitution).
1299  *	Return the expanded string or NULL if the delimiter was missing
1300  *	If pattern is specified, handle escaped ampersands, and replace
1301  *	unescaped ampersands with the lhs of the pattern.
1302  *
1303  * Results:
1304  *	A string of all the words modified appropriately.
1305  *	If length is specified, return the string length of the buffer
1306  *	If flags is specified and the last character of the pattern is a
1307  *	$ set the VAR_MATCH_END bit of flags.
1308  *
1309  * Side Effects:
1310  *	None.
1311  *-----------------------------------------------------------------------
1312  */
1313 static char *
1314 VarGetPattern(ctxt, err, tstr, delim, flags, length, pattern)
1315     GNode *ctxt;
1316     int err;
1317     char **tstr;
1318     int delim;
1319     int *flags;
1320     int *length;
1321     VarPattern *pattern;
1322 {
1323     char *cp;
1324     Buffer buf = Buf_Init(0);
1325     int junk;
1326     if (length == NULL)
1327 	length = &junk;
1328 
1329 #define IS_A_MATCH(cp, delim) \
1330     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
1331      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
1332 
1333     /*
1334      * Skim through until the matching delimiter is found;
1335      * pick up variable substitutions on the way. Also allow
1336      * backslashes to quote the delimiter, $, and \, but don't
1337      * touch other backslashes.
1338      */
1339     for (cp = *tstr; *cp && (*cp != delim); cp++) {
1340 	if (IS_A_MATCH(cp, delim)) {
1341 	    Buf_AddByte(buf, (Byte) cp[1]);
1342 	    cp++;
1343 	} else if (*cp == '$') {
1344 	    if (cp[1] == delim) {
1345 		if (flags == NULL)
1346 		    Buf_AddByte(buf, (Byte) *cp);
1347 		else
1348 		    /*
1349 		     * Unescaped $ at end of pattern => anchor
1350 		     * pattern at end.
1351 		     */
1352 		    *flags |= VAR_MATCH_END;
1353 	    }
1354 	    else {
1355 		char   *cp2;
1356 		int     len;
1357 		Boolean freeIt;
1358 
1359 		/*
1360 		 * If unescaped dollar sign not before the
1361 		 * delimiter, assume it's a variable
1362 		 * substitution and recurse.
1363 		 */
1364 		cp2 = Var_Parse(cp, ctxt, err, &len, &freeIt);
1365 		Buf_AddBytes(buf, strlen(cp2), (Byte *) cp2);
1366 		if (freeIt)
1367 		    free(cp2);
1368 		cp += len - 1;
1369 	    }
1370 	}
1371 	else if (pattern && *cp == '&')
1372 	    Buf_AddBytes(buf, pattern->leftLen, (Byte *)pattern->lhs);
1373 	else
1374 	    Buf_AddByte(buf, (Byte) *cp);
1375     }
1376 
1377     Buf_AddByte(buf, (Byte) '\0');
1378 
1379     if (*cp != delim) {
1380 	*tstr = cp;
1381 	*length = 0;
1382 	return NULL;
1383     }
1384     else {
1385 	*tstr = ++cp;
1386 	cp = (char *) Buf_GetAll(buf, length);
1387 	*length -= 1;	/* Don't count the NULL */
1388 	Buf_Destroy(buf, FALSE);
1389 	return cp;
1390     }
1391 }
1392 
1393 /*-
1394  *-----------------------------------------------------------------------
1395  * VarQuote --
1396  *	Quote shell meta-characters in the string
1397  *
1398  * Results:
1399  *	The quoted string
1400  *
1401  * Side Effects:
1402  *	None.
1403  *
1404  *-----------------------------------------------------------------------
1405  */
1406 static char *
1407 VarQuote(str)
1408 	char *str;
1409 {
1410 
1411     Buffer  	  buf;
1412     /* This should cover most shells :-( */
1413     static char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
1414 
1415     buf = Buf_Init (MAKE_BSIZE);
1416     for (; *str; str++) {
1417 	if (strchr(meta, *str) != NULL)
1418 	    Buf_AddByte(buf, (Byte)'\\');
1419 	Buf_AddByte(buf, (Byte)*str);
1420     }
1421     Buf_AddByte(buf, (Byte) '\0');
1422     str = (char *)Buf_GetAll (buf, (int *)NULL);
1423     Buf_Destroy (buf, FALSE);
1424     return str;
1425 }
1426 
1427 
1428 /*-
1429  *-----------------------------------------------------------------------
1430  * Var_Parse --
1431  *	Given the start of a variable invocation, extract the variable
1432  *	name and find its value, then modify it according to the
1433  *	specification.
1434  *
1435  * Results:
1436  *	The (possibly-modified) value of the variable or var_Error if the
1437  *	specification is invalid. The length of the specification is
1438  *	placed in *lengthPtr (for invalid specifications, this is just
1439  *	2...?).
1440  *	A Boolean in *freePtr telling whether the returned string should
1441  *	be freed by the caller.
1442  *
1443  * Side Effects:
1444  *	None.
1445  *
1446  *-----------------------------------------------------------------------
1447  */
1448 char *
1449 Var_Parse (str, ctxt, err, lengthPtr, freePtr)
1450     char    	  *str;	    	/* The string to parse */
1451     GNode   	  *ctxt;    	/* The context for the variable */
1452     Boolean 	    err;    	/* TRUE if undefined variables are an error */
1453     int	    	    *lengthPtr;	/* OUT: The length of the specification */
1454     Boolean 	    *freePtr; 	/* OUT: TRUE if caller should free result */
1455 {
1456     register char   *tstr;    	/* Pointer into str */
1457     Var	    	    *v;	    	/* Variable in invocation */
1458     char   	    *cp;    	/* Secondary pointer into str (place marker
1459 				 * for tstr) */
1460     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
1461     register char   endc;    	/* Ending character when variable in parens
1462 				 * or braces */
1463     register char   startc=0;	/* Starting character when variable in parens
1464 				 * or braces */
1465     int             cnt;	/* Used to count brace pairs when variable in
1466 				 * in parens or braces */
1467     int		    vlen;	/* Length of variable name */
1468     char    	    *start;
1469     char	     delim;
1470     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
1471 				 * expanding it in a non-local context. This
1472 				 * is done to support dynamic sources. The
1473 				 * result is just the invocation, unaltered */
1474 
1475     *freePtr = FALSE;
1476     dynamic = FALSE;
1477     start = str;
1478 
1479     if (str[1] != '(' && str[1] != '{') {
1480 	/*
1481 	 * If it's not bounded by braces of some sort, life is much simpler.
1482 	 * We just need to check for the first character and return the
1483 	 * value if it exists.
1484 	 */
1485 	char	  name[2];
1486 
1487 	name[0] = str[1];
1488 	name[1] = '\0';
1489 
1490 	v = VarFind (name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1491 	if (v == (Var *)NIL) {
1492 	    *lengthPtr = 2;
1493 
1494 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
1495 		/*
1496 		 * If substituting a local variable in a non-local context,
1497 		 * assume it's for dynamic source stuff. We have to handle
1498 		 * this specially and return the longhand for the variable
1499 		 * with the dollar sign escaped so it makes it back to the
1500 		 * caller. Only four of the local variables are treated
1501 		 * specially as they are the only four that will be set
1502 		 * when dynamic sources are expanded.
1503 		 */
1504 		switch (str[1]) {
1505 		    case '@':
1506 			return("$(.TARGET)");
1507 		    case '%':
1508 			return("$(.ARCHIVE)");
1509 		    case '*':
1510 			return("$(.PREFIX)");
1511 		    case '!':
1512 			return("$(.MEMBER)");
1513 		}
1514 	    }
1515 	    /*
1516 	     * Error
1517 	     */
1518 	    return (err ? var_Error : varNoError);
1519 	} else {
1520 	    haveModifier = FALSE;
1521 	    tstr = &str[1];
1522 	    endc = str[1];
1523 	}
1524     } else {
1525 	Buffer buf;	/* Holds the variable name */
1526 
1527 	startc = str[1];
1528 	endc = startc == '(' ? ')' : '}';
1529 	buf = Buf_Init (MAKE_BSIZE);
1530 
1531 	/*
1532 	 * Skip to the end character or a colon, whichever comes first.
1533 	 */
1534 	for (tstr = str + 2;
1535 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
1536 	     tstr++)
1537 	{
1538 	    /*
1539 	     * A variable inside a variable, expand
1540 	     */
1541 	    if (*tstr == '$') {
1542 		int rlen;
1543 		Boolean rfree;
1544 		char *rval = Var_Parse(tstr, ctxt, err, &rlen, &rfree);
1545 		if (rval != NULL) {
1546 		    Buf_AddBytes(buf, strlen(rval), (Byte *) rval);
1547 		    if (rfree)
1548 			free(rval);
1549 		}
1550 		tstr += rlen - 1;
1551 	    }
1552 	    else
1553 		Buf_AddByte(buf, (Byte) *tstr);
1554 	}
1555 	if (*tstr == ':') {
1556 	    haveModifier = TRUE;
1557 	} else if (*tstr != '\0') {
1558 	    haveModifier = FALSE;
1559 	} else {
1560 	    /*
1561 	     * If we never did find the end character, return NULL
1562 	     * right now, setting the length to be the distance to
1563 	     * the end of the string, since that's what make does.
1564 	     */
1565 	    *lengthPtr = tstr - str;
1566 	    return (var_Error);
1567 	}
1568 	*tstr = '\0';
1569 	Buf_AddByte(buf, (Byte) '\0');
1570 	str = Buf_GetAll(buf, (int *) NULL);
1571 	vlen = strlen(str);
1572 
1573 	v = VarFind (str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1574 	if ((v == (Var *)NIL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
1575 	    (vlen == 2) && (str[1] == 'F' || str[1] == 'D'))
1576 	{
1577 	    /*
1578 	     * Check for bogus D and F forms of local variables since we're
1579 	     * in a local context and the name is the right length.
1580 	     */
1581 	    switch(*str) {
1582 		case '@':
1583 		case '%':
1584 		case '*':
1585 		case '!':
1586 		case '>':
1587 		case '<':
1588 		{
1589 		    char    vname[2];
1590 		    char    *val;
1591 
1592 		    /*
1593 		     * Well, it's local -- go look for it.
1594 		     */
1595 		    vname[0] = *str;
1596 		    vname[1] = '\0';
1597 		    v = VarFind(vname, ctxt, 0);
1598 
1599 		    if (v != (Var *)NIL) {
1600 			/*
1601 			 * No need for nested expansion or anything, as we're
1602 			 * the only one who sets these things and we sure don't
1603 			 * but nested invocations in them...
1604 			 */
1605 			val = (char *)Buf_GetAll(v->val, (int *)NULL);
1606 
1607 			if (str[1] == 'D') {
1608 			    val = VarModify(val, VarHead, (ClientData)0);
1609 			} else {
1610 			    val = VarModify(val, VarTail, (ClientData)0);
1611 			}
1612 			/*
1613 			 * Resulting string is dynamically allocated, so
1614 			 * tell caller to free it.
1615 			 */
1616 			*freePtr = TRUE;
1617 			*lengthPtr = tstr-start+1;
1618 			*tstr = endc;
1619 			Buf_Destroy (buf, TRUE);
1620 			return(val);
1621 		    }
1622 		    break;
1623 		}
1624 	    }
1625 	}
1626 
1627 	if (v == (Var *)NIL) {
1628 	    if (((vlen == 1) ||
1629 		 (((vlen == 2) && (str[1] == 'F' ||
1630 					 str[1] == 'D')))) &&
1631 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
1632 	    {
1633 		/*
1634 		 * If substituting a local variable in a non-local context,
1635 		 * assume it's for dynamic source stuff. We have to handle
1636 		 * this specially and return the longhand for the variable
1637 		 * with the dollar sign escaped so it makes it back to the
1638 		 * caller. Only four of the local variables are treated
1639 		 * specially as they are the only four that will be set
1640 		 * when dynamic sources are expanded.
1641 		 */
1642 		switch (*str) {
1643 		    case '@':
1644 		    case '%':
1645 		    case '*':
1646 		    case '!':
1647 			dynamic = TRUE;
1648 			break;
1649 		}
1650 	    } else if ((vlen > 2) && (*str == '.') &&
1651 		       isupper((unsigned char) str[1]) &&
1652 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
1653 	    {
1654 		int	len;
1655 
1656 		len = vlen - 1;
1657 		if ((strncmp(str, ".TARGET", len) == 0) ||
1658 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
1659 		    (strncmp(str, ".PREFIX", len) == 0) ||
1660 		    (strncmp(str, ".MEMBER", len) == 0))
1661 		{
1662 		    dynamic = TRUE;
1663 		}
1664 	    }
1665 
1666 	    if (!haveModifier) {
1667 		/*
1668 		 * No modifiers -- have specification length so we can return
1669 		 * now.
1670 		 */
1671 		*lengthPtr = tstr - start + 1;
1672 		*tstr = endc;
1673 		if (dynamic) {
1674 		    str = emalloc(*lengthPtr + 1);
1675 		    strncpy(str, start, *lengthPtr);
1676 		    str[*lengthPtr] = '\0';
1677 		    *freePtr = TRUE;
1678 		    Buf_Destroy (buf, TRUE);
1679 		    return(str);
1680 		} else {
1681 		    Buf_Destroy (buf, TRUE);
1682 		    return (err ? var_Error : varNoError);
1683 		}
1684 	    } else {
1685 		/*
1686 		 * Still need to get to the end of the variable specification,
1687 		 * so kludge up a Var structure for the modifications
1688 		 */
1689 		v = (Var *) emalloc(sizeof(Var));
1690 		v->name = &str[1];
1691 		v->val = Buf_Init(1);
1692 		v->flags = VAR_JUNK;
1693 	    }
1694 	}
1695 	Buf_Destroy (buf, TRUE);
1696     }
1697 
1698 
1699     if (v->flags & VAR_IN_USE) {
1700 	Fatal("Variable %s is recursive.", v->name);
1701 	/*NOTREACHED*/
1702     } else {
1703 	v->flags |= VAR_IN_USE;
1704     }
1705     /*
1706      * Before doing any modification, we have to make sure the value
1707      * has been fully expanded. If it looks like recursion might be
1708      * necessary (there's a dollar sign somewhere in the variable's value)
1709      * we just call Var_Subst to do any other substitutions that are
1710      * necessary. Note that the value returned by Var_Subst will have
1711      * been dynamically-allocated, so it will need freeing when we
1712      * return.
1713      */
1714     str = (char *)Buf_GetAll(v->val, (int *)NULL);
1715     if (strchr (str, '$') != (char *)NULL) {
1716 	str = Var_Subst(NULL, str, ctxt, err);
1717 	*freePtr = TRUE;
1718     }
1719 
1720     v->flags &= ~VAR_IN_USE;
1721 
1722     /*
1723      * Now we need to apply any modifiers the user wants applied.
1724      * These are:
1725      *  	  :M<pattern>	words which match the given <pattern>.
1726      *  	  	    	<pattern> is of the standard file
1727      *  	  	    	wildcarding form.
1728      *  	  :S<d><pat1><d><pat2><d>[g]
1729      *  	  	    	Substitute <pat2> for <pat1> in the value
1730      *  	  :C<d><pat1><d><pat2><d>[g]
1731      *  	  	    	Substitute <pat2> for regex <pat1> in the value
1732      *  	  :H	    	Substitute the head of each word
1733      *  	  :T	    	Substitute the tail of each word
1734      *  	  :E	    	Substitute the extension (minus '.') of
1735      *  	  	    	each word
1736      *  	  :R	    	Substitute the root of each word
1737      *  	  	    	(pathname minus the suffix).
1738      *		  :O		Sort words in variable.
1739      *		  :?<true-value>:<false-value>
1740      *				If the variable evaluates to true, return
1741      *				true value, else return the second value.
1742      *	    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
1743      *	    	    	    	the invocation.
1744      */
1745     if ((str != (char *)NULL) && haveModifier) {
1746 	/*
1747 	 * Skip initial colon while putting it back.
1748 	 */
1749 	*tstr++ = ':';
1750 	while (*tstr != endc) {
1751 	    char	*newStr;    /* New value to return */
1752 	    char	termc;	    /* Character which terminated scan */
1753 
1754 	    if (DEBUG(VAR)) {
1755 		printf("Applying :%c to \"%s\"\n", *tstr, str);
1756 	    }
1757 	    switch (*tstr) {
1758 		case 'N':
1759 		case 'M':
1760 		{
1761 		    char    *pattern;
1762 		    char    *cp2;
1763 		    Boolean copy;
1764 
1765 		    copy = FALSE;
1766 		    for (cp = tstr + 1;
1767 			 *cp != '\0' && *cp != ':' && *cp != endc;
1768 			 cp++)
1769 		    {
1770 			if (*cp == '\\' && (cp[1] == ':' || cp[1] == endc)){
1771 			    copy = TRUE;
1772 			    cp++;
1773 			}
1774 		    }
1775 		    termc = *cp;
1776 		    *cp = '\0';
1777 		    if (copy) {
1778 			/*
1779 			 * Need to compress the \:'s out of the pattern, so
1780 			 * allocate enough room to hold the uncompressed
1781 			 * pattern (note that cp started at tstr+1, so
1782 			 * cp - tstr takes the null byte into account) and
1783 			 * compress the pattern into the space.
1784 			 */
1785 			pattern = emalloc(cp - tstr);
1786 			for (cp2 = pattern, cp = tstr + 1;
1787 			     *cp != '\0';
1788 			     cp++, cp2++)
1789 			{
1790 			    if ((*cp == '\\') &&
1791 				(cp[1] == ':' || cp[1] == endc)) {
1792 				    cp++;
1793 			    }
1794 			    *cp2 = *cp;
1795 			}
1796 			*cp2 = '\0';
1797 		    } else {
1798 			pattern = &tstr[1];
1799 		    }
1800 		    if (*tstr == 'M' || *tstr == 'm') {
1801 			newStr = VarModify(str, VarMatch, (ClientData)pattern);
1802 		    } else {
1803 			newStr = VarModify(str, VarNoMatch,
1804 					   (ClientData)pattern);
1805 		    }
1806 		    if (copy) {
1807 			free(pattern);
1808 		    }
1809 		    break;
1810 		}
1811 		case 'S':
1812 		{
1813 		    VarPattern 	    pattern;
1814 
1815 		    pattern.flags = 0;
1816 		    delim = tstr[1];
1817 		    tstr += 2;
1818 
1819 		    /*
1820 		     * If pattern begins with '^', it is anchored to the
1821 		     * start of the word -- skip over it and flag pattern.
1822 		     */
1823 		    if (*tstr == '^') {
1824 			pattern.flags |= VAR_MATCH_START;
1825 			tstr += 1;
1826 		    }
1827 
1828 		    cp = tstr;
1829 		    if ((pattern.lhs = VarGetPattern(ctxt, err, &cp, delim,
1830 			&pattern.flags, &pattern.leftLen, NULL)) == NULL)
1831 			goto cleanup;
1832 
1833 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
1834 			NULL, &pattern.rightLen, &pattern)) == NULL)
1835 			goto cleanup;
1836 
1837 		    /*
1838 		     * Check for global substitution. If 'g' after the final
1839 		     * delimiter, substitution is global and is marked that
1840 		     * way.
1841 		     */
1842 		    for (;; cp++) {
1843 			switch (*cp) {
1844 			case 'g':
1845 			    pattern.flags |= VAR_SUB_GLOBAL;
1846 			    continue;
1847 			case '1':
1848 			    pattern.flags |= VAR_SUB_ONE;
1849 			    continue;
1850 			}
1851 			break;
1852 		    }
1853 
1854 		    termc = *cp;
1855 		    newStr = VarModify(str, VarSubstitute,
1856 				       (ClientData)&pattern);
1857 
1858 		    /*
1859 		     * Free the two strings.
1860 		     */
1861 		    free(pattern.lhs);
1862 		    free(pattern.rhs);
1863 		    break;
1864 		}
1865 		case '?':
1866 		{
1867 		    VarPattern 	pattern;
1868 		    Boolean	value;
1869 
1870 		    /* find ':', and then substitute accordingly */
1871 
1872 		    pattern.flags = 0;
1873 
1874 		    cp = ++tstr;
1875 		    delim = ':';
1876 		    if ((pattern.lhs = VarGetPattern(ctxt, err, &cp, delim,
1877 			NULL, &pattern.leftLen, NULL)) == NULL)
1878 			goto cleanup;
1879 
1880 		    delim = '}';
1881 		    if ((pattern.rhs = VarGetPattern(ctxt, err, &cp, delim,
1882 			NULL, &pattern.rightLen, NULL)) == NULL)
1883 			goto cleanup;
1884 
1885 		    termc = *--cp;
1886 		    delim = '\0';
1887 		    if (Cond_EvalExpression(1, str, &value, 0) == COND_INVALID){
1888 			Error("Bad conditional expression `%s' in %s?%s:%s",
1889 			      str, str, pattern.lhs, pattern.rhs);
1890 			goto cleanup;
1891 		    }
1892 
1893 		    if (value) {
1894 			newStr = pattern.lhs;
1895 			free(pattern.rhs);
1896 		    } else {
1897 			newStr = pattern.rhs;
1898 			free(pattern.lhs);
1899 		    }
1900 		    break;
1901 		}
1902 #ifndef NO_REGEX
1903 		case 'C':
1904 		{
1905 		    VarREPattern    pattern;
1906 		    char           *re;
1907 		    int             error;
1908 
1909 		    pattern.flags = 0;
1910 		    delim = tstr[1];
1911 		    tstr += 2;
1912 
1913 		    cp = tstr;
1914 
1915 		    if ((re = VarGetPattern(ctxt, err, &cp, delim, NULL,
1916 			NULL, NULL)) == NULL)
1917 			goto cleanup;
1918 
1919 		    if ((pattern.replace = VarGetPattern(ctxt, err, &cp,
1920 			delim, NULL, NULL, NULL)) == NULL){
1921 			free(re);
1922 			goto cleanup;
1923 		    }
1924 
1925 		    for (;; cp++) {
1926 			switch (*cp) {
1927 			case 'g':
1928 			    pattern.flags |= VAR_SUB_GLOBAL;
1929 			    continue;
1930 			case '1':
1931 			    pattern.flags |= VAR_SUB_ONE;
1932 			    continue;
1933 			}
1934 			break;
1935 		    }
1936 
1937 		    termc = *cp;
1938 
1939 		    error = regcomp(&pattern.re, re, REG_EXTENDED);
1940 		    free(re);
1941 		    if (error)  {
1942 			*lengthPtr = cp - start + 1;
1943 			VarREError(error, &pattern.re, "RE substitution error");
1944 			free(pattern.replace);
1945 			return (var_Error);
1946 		    }
1947 
1948 		    pattern.nsub = pattern.re.re_nsub + 1;
1949 		    if (pattern.nsub < 1)
1950 			pattern.nsub = 1;
1951 		    if (pattern.nsub > 10)
1952 			pattern.nsub = 10;
1953 		    pattern.matches = emalloc(pattern.nsub *
1954 					      sizeof(regmatch_t));
1955 		    newStr = VarModify(str, VarRESubstitute,
1956 				       (ClientData) &pattern);
1957 		    regfree(&pattern.re);
1958 		    free(pattern.replace);
1959 		    free(pattern.matches);
1960 		    break;
1961 		}
1962 #endif
1963 		case 'Q':
1964 		    if (tstr[1] == endc || tstr[1] == ':') {
1965 			newStr = VarQuote (str);
1966 			cp = tstr + 1;
1967 			termc = *cp;
1968 			break;
1969 		    }
1970 		    /*FALLTHRU*/
1971 		case 'T':
1972 		    if (tstr[1] == endc || tstr[1] == ':') {
1973 			newStr = VarModify (str, VarTail, (ClientData)0);
1974 			cp = tstr + 1;
1975 			termc = *cp;
1976 			break;
1977 		    }
1978 		    /*FALLTHRU*/
1979 		case 'H':
1980 		    if (tstr[1] == endc || tstr[1] == ':') {
1981 			newStr = VarModify (str, VarHead, (ClientData)0);
1982 			cp = tstr + 1;
1983 			termc = *cp;
1984 			break;
1985 		    }
1986 		    /*FALLTHRU*/
1987 		case 'E':
1988 		    if (tstr[1] == endc || tstr[1] == ':') {
1989 			newStr = VarModify (str, VarSuffix, (ClientData)0);
1990 			cp = tstr + 1;
1991 			termc = *cp;
1992 			break;
1993 		    }
1994 		    /*FALLTHRU*/
1995 		case 'R':
1996 		    if (tstr[1] == endc || tstr[1] == ':') {
1997 			newStr = VarModify (str, VarRoot, (ClientData)0);
1998 			cp = tstr + 1;
1999 			termc = *cp;
2000 			break;
2001 		    }
2002 		    /*FALLTHRU*/
2003 		case 'O':
2004 		    if (tstr[1] == endc || tstr[1] == ':') {
2005 			newStr = VarSort (str);
2006 			cp = tstr + 1;
2007 			termc = *cp;
2008 			break;
2009 		    }
2010 #ifdef SUNSHCMD
2011 		case 's':
2012 		    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
2013 			char *err;
2014 			newStr = Cmd_Exec (str, &err);
2015 			if (err)
2016 			    Error (err, str);
2017 			cp = tstr + 2;
2018 			termc = *cp;
2019 			break;
2020 		    }
2021 		    /*FALLTHRU*/
2022 #endif
2023 		default:
2024 		{
2025 #ifdef SYSVVARSUB
2026 		    /*
2027 		     * This can either be a bogus modifier or a System-V
2028 		     * substitution command.
2029 		     */
2030 		    VarPattern      pattern;
2031 		    Boolean         eqFound;
2032 
2033 		    pattern.flags = 0;
2034 		    eqFound = FALSE;
2035 		    /*
2036 		     * First we make a pass through the string trying
2037 		     * to verify it is a SYSV-make-style translation:
2038 		     * it must be: <string1>=<string2>)
2039 		     */
2040 		    cp = tstr;
2041 		    cnt = 1;
2042 		    while (*cp != '\0' && cnt) {
2043 			if (*cp == '=') {
2044 			    eqFound = TRUE;
2045 			    /* continue looking for endc */
2046 			}
2047 			else if (*cp == endc)
2048 			    cnt--;
2049 			else if (*cp == startc)
2050 			    cnt++;
2051 			if (cnt)
2052 			    cp++;
2053 		    }
2054 		    if (*cp == endc && eqFound) {
2055 
2056 			/*
2057 			 * Now we break this sucker into the lhs and
2058 			 * rhs. We must null terminate them of course.
2059 			 */
2060 			for (cp = tstr; *cp != '='; cp++)
2061 			    continue;
2062 			pattern.lhs = tstr;
2063 			pattern.leftLen = cp - tstr;
2064 			*cp++ = '\0';
2065 
2066 			pattern.rhs = cp;
2067 			cnt = 1;
2068 			while (cnt) {
2069 			    if (*cp == endc)
2070 				cnt--;
2071 			    else if (*cp == startc)
2072 				cnt++;
2073 			    if (cnt)
2074 				cp++;
2075 			}
2076 			pattern.rightLen = cp - pattern.rhs;
2077 			*cp = '\0';
2078 
2079 			/*
2080 			 * SYSV modifications happen through the whole
2081 			 * string. Note the pattern is anchored at the end.
2082 			 */
2083 			newStr = VarModify(str, VarSYSVMatch,
2084 					   (ClientData)&pattern);
2085 
2086 			/*
2087 			 * Restore the nulled characters
2088 			 */
2089 			pattern.lhs[pattern.leftLen] = '=';
2090 			pattern.rhs[pattern.rightLen] = endc;
2091 			termc = endc;
2092 		    } else
2093 #endif
2094 		    {
2095 			Error ("Unknown modifier '%c'\n", *tstr);
2096 			for (cp = tstr+1;
2097 			     *cp != ':' && *cp != endc && *cp != '\0';
2098 			     cp++)
2099 				 continue;
2100 			termc = *cp;
2101 			newStr = var_Error;
2102 		    }
2103 		}
2104 	    }
2105 	    if (DEBUG(VAR)) {
2106 		printf("Result is \"%s\"\n", newStr);
2107 	    }
2108 
2109 	    if (*freePtr) {
2110 		free (str);
2111 	    }
2112 	    str = newStr;
2113 	    if (str != var_Error) {
2114 		*freePtr = TRUE;
2115 	    } else {
2116 		*freePtr = FALSE;
2117 	    }
2118 	    if (termc == '\0') {
2119 		Error("Unclosed variable specification for %s", v->name);
2120 	    } else if (termc == ':') {
2121 		*cp++ = termc;
2122 	    } else {
2123 		*cp = termc;
2124 	    }
2125 	    tstr = cp;
2126 	}
2127 	*lengthPtr = tstr - start + 1;
2128     } else {
2129 	*lengthPtr = tstr - start + 1;
2130 	*tstr = endc;
2131     }
2132 
2133     if (v->flags & VAR_FROM_ENV) {
2134 	Boolean	  destroy = FALSE;
2135 
2136 	if (str != (char *)Buf_GetAll(v->val, (int *)NULL)) {
2137 	    destroy = TRUE;
2138 	} else {
2139 	    /*
2140 	     * Returning the value unmodified, so tell the caller to free
2141 	     * the thing.
2142 	     */
2143 	    *freePtr = TRUE;
2144 	}
2145 	free(v->name);
2146 	Buf_Destroy(v->val, destroy);
2147 	free((Address)v);
2148     } else if (v->flags & VAR_JUNK) {
2149 	/*
2150 	 * Perform any free'ing needed and set *freePtr to FALSE so the caller
2151 	 * doesn't try to free a static pointer.
2152 	 */
2153 	if (*freePtr) {
2154 	    free(str);
2155 	}
2156 	*freePtr = FALSE;
2157 	Buf_Destroy(v->val, TRUE);
2158 	free((Address)v);
2159 	if (dynamic) {
2160 	    str = emalloc(*lengthPtr + 1);
2161 	    strncpy(str, start, *lengthPtr);
2162 	    str[*lengthPtr] = '\0';
2163 	    *freePtr = TRUE;
2164 	} else {
2165 	    str = var_Error;
2166 	}
2167     }
2168     return (str);
2169 
2170 cleanup:
2171     *lengthPtr = cp - start + 1;
2172     if (*freePtr)
2173 	free(str);
2174     if (delim != '\0')
2175 	Error("Unclosed substitution for %s (%c missing)",
2176 	      v->name, delim);
2177     return (var_Error);
2178 }
2179 
2180 /*-
2181  *-----------------------------------------------------------------------
2182  * Var_Subst  --
2183  *	Substitute for all variables in the given string in the given context
2184  *	If undefErr is TRUE, Parse_Error will be called when an undefined
2185  *	variable is encountered.
2186  *
2187  * Results:
2188  *	The resulting string.
2189  *
2190  * Side Effects:
2191  *	None. The old string must be freed by the caller
2192  *-----------------------------------------------------------------------
2193  */
2194 char *
2195 Var_Subst (var, str, ctxt, undefErr)
2196     char	  *var;		    /* Named variable || NULL for all */
2197     char 	  *str;	    	    /* the string in which to substitute */
2198     GNode         *ctxt;	    /* the context wherein to find variables */
2199     Boolean 	  undefErr; 	    /* TRUE if undefineds are an error */
2200 {
2201     Buffer  	  buf;	    	    /* Buffer for forming things */
2202     char    	  *val;		    /* Value to substitute for a variable */
2203     int	    	  length;   	    /* Length of the variable invocation */
2204     Boolean 	  doFree;   	    /* Set true if val should be freed */
2205     static Boolean errorReported;   /* Set true if an error has already
2206 				     * been reported to prevent a plethora
2207 				     * of messages when recursing */
2208 
2209     buf = Buf_Init (MAKE_BSIZE);
2210     errorReported = FALSE;
2211 
2212     while (*str) {
2213 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
2214 	    /*
2215 	     * A dollar sign may be escaped either with another dollar sign.
2216 	     * In such a case, we skip over the escape character and store the
2217 	     * dollar sign into the buffer directly.
2218 	     */
2219 	    str++;
2220 	    Buf_AddByte(buf, (Byte)*str);
2221 	    str++;
2222 	} else if (*str != '$') {
2223 	    /*
2224 	     * Skip as many characters as possible -- either to the end of
2225 	     * the string or to the next dollar sign (variable invocation).
2226 	     */
2227 	    char  *cp;
2228 
2229 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
2230 		continue;
2231 	    Buf_AddBytes(buf, str - cp, (Byte *)cp);
2232 	} else {
2233 	    if (var != NULL) {
2234 		int expand;
2235 		for (;;) {
2236 		    if (str[1] != '(' && str[1] != '{') {
2237 			if (str[1] != *var) {
2238 			    Buf_AddBytes(buf, 2, (Byte *) str);
2239 			    str += 2;
2240 			    expand = FALSE;
2241 			}
2242 			else
2243 			    expand = TRUE;
2244 			break;
2245 		    }
2246 		    else {
2247 			char *p;
2248 
2249 			/*
2250 			 * Scan up to the end of the variable name.
2251 			 */
2252 			for (p = &str[2]; *p &&
2253 			     *p != ':' && *p != ')' && *p != '}'; p++)
2254 			    if (*p == '$')
2255 				break;
2256 			/*
2257 			 * A variable inside the variable. We cannot expand
2258 			 * the external variable yet, so we try again with
2259 			 * the nested one
2260 			 */
2261 			if (*p == '$') {
2262 			    Buf_AddBytes(buf, p - str, (Byte *) str);
2263 			    str = p;
2264 			    continue;
2265 			}
2266 
2267 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
2268 			    var[p - str - 2] != '\0') {
2269 			    /*
2270 			     * Not the variable we want to expand, scan
2271 			     * until the next variable
2272 			     */
2273 			    for (;*p != '$' && *p != '\0'; p++)
2274 				continue;
2275 			    Buf_AddBytes(buf, p - str, (Byte *) str);
2276 			    str = p;
2277 			    expand = FALSE;
2278 			}
2279 			else
2280 			    expand = TRUE;
2281 			break;
2282 		    }
2283 		}
2284 		if (!expand)
2285 		    continue;
2286 	    }
2287 
2288 	    val = Var_Parse (str, ctxt, undefErr, &length, &doFree);
2289 
2290 	    /*
2291 	     * When we come down here, val should either point to the
2292 	     * value of this variable, suitably modified, or be NULL.
2293 	     * Length should be the total length of the potential
2294 	     * variable invocation (from $ to end character...)
2295 	     */
2296 	    if (val == var_Error || val == varNoError) {
2297 		/*
2298 		 * If performing old-time variable substitution, skip over
2299 		 * the variable and continue with the substitution. Otherwise,
2300 		 * store the dollar sign and advance str so we continue with
2301 		 * the string...
2302 		 */
2303 		if (oldVars) {
2304 		    str += length;
2305 		} else if (undefErr) {
2306 		    /*
2307 		     * If variable is undefined, complain and skip the
2308 		     * variable. The complaint will stop us from doing anything
2309 		     * when the file is parsed.
2310 		     */
2311 		    if (!errorReported) {
2312 			Parse_Error (PARSE_FATAL,
2313 				     "Undefined variable \"%.*s\"",length,str);
2314 		    }
2315 		    str += length;
2316 		    errorReported = TRUE;
2317 		} else {
2318 		    Buf_AddByte (buf, (Byte)*str);
2319 		    str += 1;
2320 		}
2321 	    } else {
2322 		/*
2323 		 * We've now got a variable structure to store in. But first,
2324 		 * advance the string pointer.
2325 		 */
2326 		str += length;
2327 
2328 		/*
2329 		 * Copy all the characters from the variable value straight
2330 		 * into the new string.
2331 		 */
2332 		Buf_AddBytes (buf, strlen (val), (Byte *)val);
2333 		if (doFree) {
2334 		    free ((Address)val);
2335 		}
2336 	    }
2337 	}
2338     }
2339 
2340     Buf_AddByte (buf, '\0');
2341     str = (char *)Buf_GetAll (buf, (int *)NULL);
2342     Buf_Destroy (buf, FALSE);
2343     return (str);
2344 }
2345 
2346 /*-
2347  *-----------------------------------------------------------------------
2348  * Var_GetTail --
2349  *	Return the tail from each of a list of words. Used to set the
2350  *	System V local variables.
2351  *
2352  * Results:
2353  *	The resulting string.
2354  *
2355  * Side Effects:
2356  *	None.
2357  *
2358  *-----------------------------------------------------------------------
2359  */
2360 char *
2361 Var_GetTail(file)
2362     char    	*file;	    /* Filename to modify */
2363 {
2364     return(VarModify(file, VarTail, (ClientData)0));
2365 }
2366 
2367 /*-
2368  *-----------------------------------------------------------------------
2369  * Var_GetHead --
2370  *	Find the leading components of a (list of) filename(s).
2371  *	XXX: VarHead does not replace foo by ., as (sun) System V make
2372  *	does.
2373  *
2374  * Results:
2375  *	The leading components.
2376  *
2377  * Side Effects:
2378  *	None.
2379  *
2380  *-----------------------------------------------------------------------
2381  */
2382 char *
2383 Var_GetHead(file)
2384     char    	*file;	    /* Filename to manipulate */
2385 {
2386     return(VarModify(file, VarHead, (ClientData)0));
2387 }
2388 
2389 /*-
2390  *-----------------------------------------------------------------------
2391  * Var_Init --
2392  *	Initialize the module
2393  *
2394  * Results:
2395  *	None
2396  *
2397  * Side Effects:
2398  *	The VAR_CMD and VAR_GLOBAL contexts are created
2399  *-----------------------------------------------------------------------
2400  */
2401 void
2402 Var_Init ()
2403 {
2404     VAR_GLOBAL = Targ_NewGN ("Global");
2405     VAR_CMD = Targ_NewGN ("Command");
2406 
2407 }
2408 
2409 
2410 void
2411 Var_End ()
2412 {
2413 }
2414 
2415 
2416 /****************** PRINT DEBUGGING INFO *****************/
2417 static void
2418 VarPrintVar (vp)
2419     ClientData vp;
2420 {
2421     Var    *v = (Var *) vp;
2422     printf ("%-16s = %s\n", v->name, (char *) Buf_GetAll(v->val, (int *)NULL));
2423 }
2424 
2425 /*-
2426  *-----------------------------------------------------------------------
2427  * Var_Dump --
2428  *	print all variables in a context
2429  *-----------------------------------------------------------------------
2430  */
2431 void
2432 Var_Dump (ctxt)
2433     GNode          *ctxt;
2434 {
2435     Hash_Search search;
2436     Hash_Entry *h;
2437 
2438     for (h = Hash_EnumFirst(&ctxt->context, &search);
2439 	 h != NULL;
2440 	 h = Hash_EnumNext(&search)) {
2441 	    VarPrintVar(Hash_GetValue(h));
2442     }
2443 }
2444