xref: /freebsd/contrib/bmake/var.c (revision 732a02b4e77866604a120a275c082bb6221bd2ff)
1 /*	$NetBSD: var.c,v 1.221 2018/12/21 05:50:19 sjg 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 1.221 2018/12/21 05:50:19 sjg 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 1.221 2018/12/21 05:50:19 sjg 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 #include    <sys/stat.h>
127 #ifndef NO_REGEX
128 #include    <sys/types.h>
129 #include    <regex.h>
130 #endif
131 #include    <ctype.h>
132 #include    <stdlib.h>
133 #include    <limits.h>
134 #include    <time.h>
135 
136 #include    "make.h"
137 #include    "buf.h"
138 #include    "dir.h"
139 #include    "job.h"
140 #include    "metachar.h"
141 
142 extern int makelevel;
143 /*
144  * This lets us tell if we have replaced the original environ
145  * (which we cannot free).
146  */
147 char **savedEnv = NULL;
148 
149 /*
150  * This is a harmless return value for Var_Parse that can be used by Var_Subst
151  * to determine if there was an error in parsing -- easier than returning
152  * a flag, as things outside this module don't give a hoot.
153  */
154 char 	var_Error[] = "";
155 
156 /*
157  * Similar to var_Error, but returned when the 'VARF_UNDEFERR' flag for
158  * Var_Parse is not set. Why not just use a constant? Well, gcc likes
159  * to condense identical string instances...
160  */
161 static char	varNoError[] = "";
162 
163 /*
164  * Traditionally we consume $$ during := like any other expansion.
165  * Other make's do not.
166  * This knob allows controlling the behavior.
167  * FALSE for old behavior.
168  * TRUE for new compatible.
169  */
170 #define SAVE_DOLLARS ".MAKE.SAVE_DOLLARS"
171 static Boolean save_dollars = FALSE;
172 
173 /*
174  * Internally, variables are contained in four different contexts.
175  *	1) the environment. They may not be changed. If an environment
176  *	    variable is appended-to, the result is placed in the global
177  *	    context.
178  *	2) the global context. Variables set in the Makefile are located in
179  *	    the global context. It is the penultimate context searched when
180  *	    substituting.
181  *	3) the command-line context. All variables set on the command line
182  *	   are placed in this context. They are UNALTERABLE once placed here.
183  *	4) the local context. Each target has associated with it a context
184  *	   list. On this list are located the structures describing such
185  *	   local variables as $(@) and $(*)
186  * The four contexts are searched in the reverse order from which they are
187  * listed.
188  */
189 GNode          *VAR_INTERNAL; /* variables from make itself */
190 GNode          *VAR_GLOBAL;   /* variables from the makefile */
191 GNode          *VAR_CMD;      /* variables defined on the command-line */
192 
193 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
194 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
195 #define FIND_ENV  	0x4   /* look in the environment also */
196 
197 typedef struct Var {
198     char          *name;	/* the variable's name */
199     Buffer	  val;		/* its value */
200     int		  flags;    	/* miscellaneous status flags */
201 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
202 				     * Used to avoid recursion */
203 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
204 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
205 				     * should be destroyed when done with
206 				     * it. Used by Var_Parse for undefined,
207 				     * modified variables */
208 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
209 				     * a use for it in some modifier and
210 				     * the value is therefore valid */
211 #define VAR_EXPORTED	16 	    /* Variable is exported */
212 #define VAR_REEXPORT	32	    /* Indicate if var needs re-export.
213 				     * This would be true if it contains $'s
214 				     */
215 #define VAR_FROM_CMD	64 	    /* Variable came from command line */
216 }  Var;
217 
218 /*
219  * Exporting vars is expensive so skip it if we can
220  */
221 #define VAR_EXPORTED_NONE	0
222 #define VAR_EXPORTED_YES	1
223 #define VAR_EXPORTED_ALL	2
224 static int var_exportedVars = VAR_EXPORTED_NONE;
225 /*
226  * We pass this to Var_Export when doing the initial export
227  * or after updating an exported var.
228  */
229 #define VAR_EXPORT_PARENT	1
230 /*
231  * We pass this to Var_Export1 to tell it to leave the value alone.
232  */
233 #define VAR_EXPORT_LITERAL	2
234 
235 /* Var*Pattern flags */
236 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
237 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
238 #define VAR_SUB_MATCHED	0x04	/* There was a match */
239 #define VAR_MATCH_START	0x08	/* Match at start of word */
240 #define VAR_MATCH_END	0x10	/* Match at end of word */
241 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
242 
243 /* Var_Set flags */
244 #define VAR_NO_EXPORT	0x01	/* do not export */
245 
246 typedef struct {
247     /*
248      * The following fields are set by Var_Parse() when it
249      * encounters modifiers that need to keep state for use by
250      * subsequent modifiers within the same variable expansion.
251      */
252     Byte	varSpace;	/* Word separator in expansions */
253     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
254 				 * single big word, even if it contains
255 				 * embedded spaces (as opposed to the
256 				 * usual behaviour of treating it as
257 				 * several space-separated words). */
258 } Var_Parse_State;
259 
260 /* struct passed as 'void *' to VarSubstitute() for ":S/lhs/rhs/",
261  * to VarSYSVMatch() for ":lhs=rhs". */
262 typedef struct {
263     const char   *lhs;	    /* String to match */
264     int		  leftLen; /* Length of string */
265     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
266     int		  rightLen; /* Length of replacement */
267     int		  flags;
268 } VarPattern;
269 
270 /* struct passed as 'void *' to VarLoopExpand() for ":@tvar@str@" */
271 typedef struct {
272     GNode	*ctxt;		/* variable context */
273     char	*tvar;		/* name of temp var */
274     int		tvarLen;
275     char	*str;		/* string to expand */
276     int		strLen;
277     int		errnum;		/* errnum for not defined */
278 } VarLoop_t;
279 
280 #ifndef NO_REGEX
281 /* struct passed as 'void *' to VarRESubstitute() for ":C///" */
282 typedef struct {
283     regex_t	   re;
284     int		   nsub;
285     regmatch_t 	  *matches;
286     char 	  *replace;
287     int		   flags;
288 } VarREPattern;
289 #endif
290 
291 /* struct passed to VarSelectWords() for ":[start..end]" */
292 typedef struct {
293     int		start;		/* first word to select */
294     int		end;		/* last word to select */
295 } VarSelectWords_t;
296 
297 static Var *VarFind(const char *, GNode *, int);
298 static void VarAdd(const char *, const char *, GNode *);
299 static Boolean VarHead(GNode *, Var_Parse_State *,
300 			char *, Boolean, Buffer *, void *);
301 static Boolean VarTail(GNode *, Var_Parse_State *,
302 			char *, Boolean, Buffer *, void *);
303 static Boolean VarSuffix(GNode *, Var_Parse_State *,
304 			char *, Boolean, Buffer *, void *);
305 static Boolean VarRoot(GNode *, Var_Parse_State *,
306 			char *, Boolean, Buffer *, void *);
307 static Boolean VarMatch(GNode *, Var_Parse_State *,
308 			char *, Boolean, Buffer *, void *);
309 #ifdef SYSVVARSUB
310 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
311 			char *, Boolean, Buffer *, void *);
312 #endif
313 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
314 			char *, Boolean, Buffer *, void *);
315 #ifndef NO_REGEX
316 static void VarREError(int, regex_t *, const char *);
317 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
318 			char *, Boolean, Buffer *, void *);
319 #endif
320 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
321 			char *, Boolean, Buffer *, void *);
322 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
323 			char *, Boolean, Buffer *, void *);
324 static char *VarGetPattern(GNode *, Var_Parse_State *,
325 			   int, const char **, int, int *, int *,
326 			   VarPattern *);
327 static char *VarQuote(char *, Boolean);
328 static char *VarHash(char *);
329 static char *VarModify(GNode *, Var_Parse_State *,
330     const char *,
331     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer *, void *),
332     void *);
333 static char *VarOrder(const char *, const char);
334 static char *VarUniq(const char *);
335 static int VarWordCompare(const void *, const void *);
336 static void VarPrintVar(void *);
337 
338 #define BROPEN	'{'
339 #define BRCLOSE	'}'
340 #define PROPEN	'('
341 #define PRCLOSE	')'
342 
343 /*-
344  *-----------------------------------------------------------------------
345  * VarFind --
346  *	Find the given variable in the given context and any other contexts
347  *	indicated.
348  *
349  * Input:
350  *	name		name to find
351  *	ctxt		context in which to find it
352  *	flags		FIND_GLOBAL set means to look in the
353  *			VAR_GLOBAL context as well. FIND_CMD set means
354  *			to look in the VAR_CMD context also. FIND_ENV
355  *			set means to look in the environment
356  *
357  * Results:
358  *	A pointer to the structure describing the desired variable or
359  *	NULL if the variable does not exist.
360  *
361  * Side Effects:
362  *	None
363  *-----------------------------------------------------------------------
364  */
365 static Var *
366 VarFind(const char *name, GNode *ctxt, int flags)
367 {
368     Hash_Entry         	*var;
369     Var			*v;
370 
371 	/*
372 	 * If the variable name begins with a '.', it could very well be one of
373 	 * the local ones.  We check the name against all the local variables
374 	 * and substitute the short version in for 'name' if it matches one of
375 	 * them.
376 	 */
377 	if (*name == '.' && isupper((unsigned char) name[1]))
378 		switch (name[1]) {
379 		case 'A':
380 			if (!strcmp(name, ".ALLSRC"))
381 				name = ALLSRC;
382 			if (!strcmp(name, ".ARCHIVE"))
383 				name = ARCHIVE;
384 			break;
385 		case 'I':
386 			if (!strcmp(name, ".IMPSRC"))
387 				name = IMPSRC;
388 			break;
389 		case 'M':
390 			if (!strcmp(name, ".MEMBER"))
391 				name = MEMBER;
392 			break;
393 		case 'O':
394 			if (!strcmp(name, ".OODATE"))
395 				name = OODATE;
396 			break;
397 		case 'P':
398 			if (!strcmp(name, ".PREFIX"))
399 				name = PREFIX;
400 			break;
401 		case 'T':
402 			if (!strcmp(name, ".TARGET"))
403 				name = TARGET;
404 			break;
405 		}
406 #ifdef notyet
407     /* for compatibility with gmake */
408     if (name[0] == '^' && name[1] == '\0')
409 	    name = ALLSRC;
410 #endif
411 
412     /*
413      * First look for the variable in the given context. If it's not there,
414      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
415      * depending on the FIND_* flags in 'flags'
416      */
417     var = Hash_FindEntry(&ctxt->context, name);
418 
419     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
420 	var = Hash_FindEntry(&VAR_CMD->context, name);
421     }
422     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
423 	(ctxt != VAR_GLOBAL))
424     {
425 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
426 	if ((var == NULL) && (ctxt != VAR_INTERNAL)) {
427 	    /* VAR_INTERNAL is subordinate to VAR_GLOBAL */
428 	    var = Hash_FindEntry(&VAR_INTERNAL->context, name);
429 	}
430     }
431     if ((var == NULL) && (flags & FIND_ENV)) {
432 	char *env;
433 
434 	if ((env = getenv(name)) != NULL) {
435 	    int		len;
436 
437 	    v = bmake_malloc(sizeof(Var));
438 	    v->name = bmake_strdup(name);
439 
440 	    len = strlen(env);
441 
442 	    Buf_Init(&v->val, len + 1);
443 	    Buf_AddBytes(&v->val, len, env);
444 
445 	    v->flags = VAR_FROM_ENV;
446 	    return (v);
447 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
448 		   (ctxt != VAR_GLOBAL))
449 	{
450 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
451 	    if ((var == NULL) && (ctxt != VAR_INTERNAL)) {
452 		var = Hash_FindEntry(&VAR_INTERNAL->context, name);
453 	    }
454 	    if (var == NULL) {
455 		return NULL;
456 	    } else {
457 		return ((Var *)Hash_GetValue(var));
458 	    }
459 	} else {
460 	    return NULL;
461 	}
462     } else if (var == NULL) {
463 	return NULL;
464     } else {
465 	return ((Var *)Hash_GetValue(var));
466     }
467 }
468 
469 /*-
470  *-----------------------------------------------------------------------
471  * VarFreeEnv  --
472  *	If the variable is an environment variable, free it
473  *
474  * Input:
475  *	v		the variable
476  *	destroy		true if the value buffer should be destroyed.
477  *
478  * Results:
479  *	1 if it is an environment variable 0 ow.
480  *
481  * Side Effects:
482  *	The variable is free'ed if it is an environent variable.
483  *-----------------------------------------------------------------------
484  */
485 static Boolean
486 VarFreeEnv(Var *v, Boolean destroy)
487 {
488     if ((v->flags & VAR_FROM_ENV) == 0)
489 	return FALSE;
490     free(v->name);
491     Buf_Destroy(&v->val, destroy);
492     free(v);
493     return TRUE;
494 }
495 
496 /*-
497  *-----------------------------------------------------------------------
498  * VarAdd  --
499  *	Add a new variable of name name and value val to the given context
500  *
501  * Input:
502  *	name		name of variable to add
503  *	val		value to set it to
504  *	ctxt		context in which to set it
505  *
506  * Results:
507  *	None
508  *
509  * Side Effects:
510  *	The new variable is placed at the front of the given context
511  *	The name and val arguments are duplicated so they may
512  *	safely be freed.
513  *-----------------------------------------------------------------------
514  */
515 static void
516 VarAdd(const char *name, const char *val, GNode *ctxt)
517 {
518     Var   	  *v;
519     int		  len;
520     Hash_Entry    *h;
521 
522     v = bmake_malloc(sizeof(Var));
523 
524     len = val ? strlen(val) : 0;
525     Buf_Init(&v->val, len+1);
526     Buf_AddBytes(&v->val, len, val);
527 
528     v->flags = 0;
529 
530     h = Hash_CreateEntry(&ctxt->context, name, NULL);
531     Hash_SetValue(h, v);
532     v->name = h->name;
533     if (DEBUG(VAR) && (ctxt->flags & INTERNAL) == 0) {
534 	fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
535     }
536 }
537 
538 /*-
539  *-----------------------------------------------------------------------
540  * Var_Delete --
541  *	Remove a variable from a context.
542  *
543  * Results:
544  *	None.
545  *
546  * Side Effects:
547  *	The Var structure is removed and freed.
548  *
549  *-----------------------------------------------------------------------
550  */
551 void
552 Var_Delete(const char *name, GNode *ctxt)
553 {
554     Hash_Entry 	  *ln;
555     char *cp;
556 
557     if (strchr(name, '$')) {
558 	cp = Var_Subst(NULL, name, VAR_GLOBAL, VARF_WANTRES);
559     } else {
560 	cp = (char *)name;
561     }
562     ln = Hash_FindEntry(&ctxt->context, cp);
563     if (DEBUG(VAR)) {
564 	fprintf(debug_file, "%s:delete %s%s\n",
565 	    ctxt->name, cp, ln ? "" : " (not found)");
566     }
567     if (cp != name) {
568 	free(cp);
569     }
570     if (ln != NULL) {
571 	Var 	  *v;
572 
573 	v = (Var *)Hash_GetValue(ln);
574 	if ((v->flags & VAR_EXPORTED)) {
575 	    unsetenv(v->name);
576 	}
577 	if (strcmp(MAKE_EXPORTED, v->name) == 0) {
578 	    var_exportedVars = VAR_EXPORTED_NONE;
579 	}
580 	if (v->name != ln->name)
581 		free(v->name);
582 	Hash_DeleteEntry(&ctxt->context, ln);
583 	Buf_Destroy(&v->val, TRUE);
584 	free(v);
585     }
586 }
587 
588 
589 /*
590  * Export a var.
591  * We ignore make internal variables (those which start with '.')
592  * Also we jump through some hoops to avoid calling setenv
593  * more than necessary since it can leak.
594  * We only manipulate flags of vars if 'parent' is set.
595  */
596 static int
597 Var_Export1(const char *name, int flags)
598 {
599     char tmp[BUFSIZ];
600     Var *v;
601     char *val = NULL;
602     int n;
603     int parent = (flags & VAR_EXPORT_PARENT);
604 
605     if (*name == '.')
606 	return 0;			/* skip internals */
607     if (!name[1]) {
608 	/*
609 	 * A single char.
610 	 * If it is one of the vars that should only appear in
611 	 * local context, skip it, else we can get Var_Subst
612 	 * into a loop.
613 	 */
614 	switch (name[0]) {
615 	case '@':
616 	case '%':
617 	case '*':
618 	case '!':
619 	    return 0;
620 	}
621     }
622     v = VarFind(name, VAR_GLOBAL, 0);
623     if (v == NULL) {
624 	return 0;
625     }
626     if (!parent &&
627 	(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
628 	return 0;			/* nothing to do */
629     }
630     val = Buf_GetAll(&v->val, NULL);
631     if ((flags & VAR_EXPORT_LITERAL) == 0 && strchr(val, '$')) {
632 	if (parent) {
633 	    /*
634 	     * Flag this as something we need to re-export.
635 	     * No point actually exporting it now though,
636 	     * the child can do it at the last minute.
637 	     */
638 	    v->flags |= (VAR_EXPORTED|VAR_REEXPORT);
639 	    return 1;
640 	}
641 	if (v->flags & VAR_IN_USE) {
642 	    /*
643 	     * We recursed while exporting in a child.
644 	     * This isn't going to end well, just skip it.
645 	     */
646 	    return 0;
647 	}
648 	n = snprintf(tmp, sizeof(tmp), "${%s}", name);
649 	if (n < (int)sizeof(tmp)) {
650 	    val = Var_Subst(NULL, tmp, VAR_GLOBAL, VARF_WANTRES);
651 	    setenv(name, val, 1);
652 	    free(val);
653 	}
654     } else {
655 	if (parent) {
656 	    v->flags &= ~VAR_REEXPORT;	/* once will do */
657 	}
658 	if (parent || !(v->flags & VAR_EXPORTED)) {
659 	    setenv(name, val, 1);
660 	}
661     }
662     /*
663      * This is so Var_Set knows to call Var_Export again...
664      */
665     if (parent) {
666 	v->flags |= VAR_EXPORTED;
667     }
668     return 1;
669 }
670 
671 /*
672  * This gets called from our children.
673  */
674 void
675 Var_ExportVars(void)
676 {
677     char tmp[BUFSIZ];
678     Hash_Entry         	*var;
679     Hash_Search 	state;
680     Var *v;
681     char *val;
682     int n;
683 
684     /*
685      * Several make's support this sort of mechanism for tracking
686      * recursion - but each uses a different name.
687      * We allow the makefiles to update MAKELEVEL and ensure
688      * children see a correctly incremented value.
689      */
690     snprintf(tmp, sizeof(tmp), "%d", makelevel + 1);
691     setenv(MAKE_LEVEL_ENV, tmp, 1);
692 
693     if (VAR_EXPORTED_NONE == var_exportedVars)
694 	return;
695 
696     if (VAR_EXPORTED_ALL == var_exportedVars) {
697 	/*
698 	 * Ouch! This is crazy...
699 	 */
700 	for (var = Hash_EnumFirst(&VAR_GLOBAL->context, &state);
701 	     var != NULL;
702 	     var = Hash_EnumNext(&state)) {
703 	    v = (Var *)Hash_GetValue(var);
704 	    Var_Export1(v->name, 0);
705 	}
706 	return;
707     }
708     /*
709      * We have a number of exported vars,
710      */
711     n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
712     if (n < (int)sizeof(tmp)) {
713 	char **av;
714 	char *as;
715 	int ac;
716 	int i;
717 
718 	val = Var_Subst(NULL, tmp, VAR_GLOBAL, VARF_WANTRES);
719 	if (*val) {
720 	    av = brk_string(val, &ac, FALSE, &as);
721 	    for (i = 0; i < ac; i++) {
722 		Var_Export1(av[i], 0);
723 	    }
724 	    free(as);
725 	    free(av);
726 	}
727 	free(val);
728     }
729 }
730 
731 /*
732  * This is called when .export is seen or
733  * .MAKE.EXPORTED is modified.
734  * It is also called when any exported var is modified.
735  */
736 void
737 Var_Export(char *str, int isExport)
738 {
739     char *name;
740     char *val;
741     char **av;
742     char *as;
743     int flags;
744     int ac;
745     int i;
746 
747     if (isExport && (!str || !str[0])) {
748 	var_exportedVars = VAR_EXPORTED_ALL; /* use with caution! */
749 	return;
750     }
751 
752     flags = 0;
753     if (strncmp(str, "-env", 4) == 0) {
754 	str += 4;
755     } else if (strncmp(str, "-literal", 8) == 0) {
756 	str += 8;
757 	flags |= VAR_EXPORT_LITERAL;
758     } else {
759 	flags |= VAR_EXPORT_PARENT;
760     }
761     val = Var_Subst(NULL, str, VAR_GLOBAL, VARF_WANTRES);
762     if (*val) {
763 	av = brk_string(val, &ac, FALSE, &as);
764 	for (i = 0; i < ac; i++) {
765 	    name = av[i];
766 	    if (!name[1]) {
767 		/*
768 		 * A single char.
769 		 * If it is one of the vars that should only appear in
770 		 * local context, skip it, else we can get Var_Subst
771 		 * into a loop.
772 		 */
773 		switch (name[0]) {
774 		case '@':
775 		case '%':
776 		case '*':
777 		case '!':
778 		    continue;
779 		}
780 	    }
781 	    if (Var_Export1(name, flags)) {
782 		if (VAR_EXPORTED_ALL != var_exportedVars)
783 		    var_exportedVars = VAR_EXPORTED_YES;
784 		if (isExport && (flags & VAR_EXPORT_PARENT)) {
785 		    Var_Append(MAKE_EXPORTED, name, VAR_GLOBAL);
786 		}
787 	    }
788 	}
789 	free(as);
790 	free(av);
791     }
792     free(val);
793 }
794 
795 
796 /*
797  * This is called when .unexport[-env] is seen.
798  */
799 extern char **environ;
800 
801 void
802 Var_UnExport(char *str)
803 {
804     char tmp[BUFSIZ];
805     char *vlist;
806     char *cp;
807     Boolean unexport_env;
808     int n;
809 
810     if (!str || !str[0]) {
811 	return; 			/* assert? */
812     }
813 
814     vlist = NULL;
815 
816     str += 8;
817     unexport_env = (strncmp(str, "-env", 4) == 0);
818     if (unexport_env) {
819 	char **newenv;
820 
821 	cp = getenv(MAKE_LEVEL_ENV);	/* we should preserve this */
822 	if (environ == savedEnv) {
823 	    /* we have been here before! */
824 	    newenv = bmake_realloc(environ, 2 * sizeof(char *));
825 	} else {
826 	    if (savedEnv) {
827 		free(savedEnv);
828 		savedEnv = NULL;
829 	    }
830 	    newenv = bmake_malloc(2 * sizeof(char *));
831 	}
832 	if (!newenv)
833 	    return;
834 	/* Note: we cannot safely free() the original environ. */
835 	environ = savedEnv = newenv;
836 	newenv[0] = NULL;
837 	newenv[1] = NULL;
838 	if (cp && *cp)
839 	    setenv(MAKE_LEVEL_ENV, cp, 1);
840     } else {
841 	for (; *str != '\n' && isspace((unsigned char) *str); str++)
842 	    continue;
843 	if (str[0] && str[0] != '\n') {
844 	    vlist = str;
845 	}
846     }
847 
848     if (!vlist) {
849 	/* Using .MAKE.EXPORTED */
850 	n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
851 	if (n < (int)sizeof(tmp)) {
852 	    vlist = Var_Subst(NULL, tmp, VAR_GLOBAL, VARF_WANTRES);
853 	}
854     }
855     if (vlist) {
856 	Var *v;
857 	char **av;
858 	char *as;
859 	int ac;
860 	int i;
861 
862 	av = brk_string(vlist, &ac, FALSE, &as);
863 	for (i = 0; i < ac; i++) {
864 	    v = VarFind(av[i], VAR_GLOBAL, 0);
865 	    if (!v)
866 		continue;
867 	    if (!unexport_env &&
868 		(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
869 		unsetenv(v->name);
870 	    }
871 	    v->flags &= ~(VAR_EXPORTED|VAR_REEXPORT);
872 	    /*
873 	     * If we are unexporting a list,
874 	     * remove each one from .MAKE.EXPORTED.
875 	     * If we are removing them all,
876 	     * just delete .MAKE.EXPORTED below.
877 	     */
878 	    if (vlist == str) {
879 		n = snprintf(tmp, sizeof(tmp),
880 			     "${" MAKE_EXPORTED ":N%s}", v->name);
881 		if (n < (int)sizeof(tmp)) {
882 		    cp = Var_Subst(NULL, tmp, VAR_GLOBAL, VARF_WANTRES);
883 		    Var_Set(MAKE_EXPORTED, cp, VAR_GLOBAL, 0);
884 		    free(cp);
885 		}
886 	    }
887 	}
888 	free(as);
889 	free(av);
890 	if (vlist != str) {
891 	    Var_Delete(MAKE_EXPORTED, VAR_GLOBAL);
892 	    free(vlist);
893 	}
894     }
895 }
896 
897 /*-
898  *-----------------------------------------------------------------------
899  * Var_Set --
900  *	Set the variable name to the value val in the given context.
901  *
902  * Input:
903  *	name		name of variable to set
904  *	val		value to give to the variable
905  *	ctxt		context in which to set it
906  *
907  * Results:
908  *	None.
909  *
910  * Side Effects:
911  *	If the variable doesn't yet exist, a new record is created for it.
912  *	Else the old value is freed and the new one stuck in its place
913  *
914  * Notes:
915  *	The variable is searched for only in its context before being
916  *	created in that context. I.e. if the context is VAR_GLOBAL,
917  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
918  *	VAR_CMD->context is searched. This is done to avoid the literally
919  *	thousands of unnecessary strcmp's that used to be done to
920  *	set, say, $(@) or $(<).
921  *	If the context is VAR_GLOBAL though, we check if the variable
922  *	was set in VAR_CMD from the command line and skip it if so.
923  *-----------------------------------------------------------------------
924  */
925 void
926 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
927 {
928     Var   *v;
929     char *expanded_name = NULL;
930 
931     /*
932      * We only look for a variable in the given context since anything set
933      * here will override anything in a lower context, so there's not much
934      * point in searching them all just to save a bit of memory...
935      */
936     if (strchr(name, '$') != NULL) {
937 	expanded_name = Var_Subst(NULL, name, ctxt, VARF_WANTRES);
938 	if (expanded_name[0] == 0) {
939 	    if (DEBUG(VAR)) {
940 		fprintf(debug_file, "Var_Set(\"%s\", \"%s\", ...) "
941 			"name expands to empty string - ignored\n",
942 			name, val);
943 	    }
944 	    free(expanded_name);
945 	    return;
946 	}
947 	name = expanded_name;
948     }
949     if (ctxt == VAR_GLOBAL) {
950 	v = VarFind(name, VAR_CMD, 0);
951 	if (v != NULL) {
952 	    if ((v->flags & VAR_FROM_CMD)) {
953 		if (DEBUG(VAR)) {
954 		    fprintf(debug_file, "%s:%s = %s ignored!\n", ctxt->name, name, val);
955 		}
956 		goto out;
957 	    }
958 	    VarFreeEnv(v, TRUE);
959 	}
960     }
961     v = VarFind(name, ctxt, 0);
962     if (v == NULL) {
963 	if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
964 	    /*
965 	     * This var would normally prevent the same name being added
966 	     * to VAR_GLOBAL, so delete it from there if needed.
967 	     * Otherwise -V name may show the wrong value.
968 	     */
969 	    Var_Delete(name, VAR_GLOBAL);
970 	}
971 	VarAdd(name, val, ctxt);
972     } else {
973 	Buf_Empty(&v->val);
974 	if (val)
975 	    Buf_AddBytes(&v->val, strlen(val), val);
976 
977 	if (DEBUG(VAR)) {
978 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
979 	}
980 	if ((v->flags & VAR_EXPORTED)) {
981 	    Var_Export1(name, VAR_EXPORT_PARENT);
982 	}
983     }
984     /*
985      * Any variables given on the command line are automatically exported
986      * to the environment (as per POSIX standard)
987      */
988     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
989 	if (v == NULL) {
990 	    /* we just added it */
991 	    v = VarFind(name, ctxt, 0);
992 	}
993 	if (v != NULL)
994 	    v->flags |= VAR_FROM_CMD;
995 	/*
996 	 * If requested, don't export these in the environment
997 	 * individually.  We still put them in MAKEOVERRIDES so
998 	 * that the command-line settings continue to override
999 	 * Makefile settings.
1000 	 */
1001 	if (varNoExportEnv != TRUE)
1002 	    setenv(name, val ? val : "", 1);
1003 
1004 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
1005     }
1006     if (*name == '.') {
1007 	if (strcmp(name, SAVE_DOLLARS) == 0)
1008 	    save_dollars = s2Boolean(val, save_dollars);
1009     }
1010 
1011  out:
1012     free(expanded_name);
1013     if (v != NULL)
1014 	VarFreeEnv(v, TRUE);
1015 }
1016 
1017 /*-
1018  *-----------------------------------------------------------------------
1019  * Var_Append --
1020  *	The variable of the given name has the given value appended to it in
1021  *	the given context.
1022  *
1023  * Input:
1024  *	name		name of variable to modify
1025  *	val		String to append to it
1026  *	ctxt		Context in which this should occur
1027  *
1028  * Results:
1029  *	None
1030  *
1031  * Side Effects:
1032  *	If the variable doesn't exist, it is created. Else the strings
1033  *	are concatenated (with a space in between).
1034  *
1035  * Notes:
1036  *	Only if the variable is being sought in the global context is the
1037  *	environment searched.
1038  *	XXX: Knows its calling circumstances in that if called with ctxt
1039  *	an actual target, it will only search that context since only
1040  *	a local variable could be being appended to. This is actually
1041  *	a big win and must be tolerated.
1042  *-----------------------------------------------------------------------
1043  */
1044 void
1045 Var_Append(const char *name, const char *val, GNode *ctxt)
1046 {
1047     Var		   *v;
1048     Hash_Entry	   *h;
1049     char *expanded_name = NULL;
1050 
1051     if (strchr(name, '$') != NULL) {
1052 	expanded_name = Var_Subst(NULL, name, ctxt, VARF_WANTRES);
1053 	if (expanded_name[0] == 0) {
1054 	    if (DEBUG(VAR)) {
1055 		fprintf(debug_file, "Var_Append(\"%s\", \"%s\", ...) "
1056 			"name expands to empty string - ignored\n",
1057 			name, val);
1058 	    }
1059 	    free(expanded_name);
1060 	    return;
1061 	}
1062 	name = expanded_name;
1063     }
1064 
1065     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? (FIND_CMD|FIND_ENV) : 0);
1066 
1067     if (v == NULL) {
1068 	Var_Set(name, val, ctxt, 0);
1069     } else if (ctxt == VAR_CMD || !(v->flags & VAR_FROM_CMD)) {
1070 	Buf_AddByte(&v->val, ' ');
1071 	Buf_AddBytes(&v->val, strlen(val), val);
1072 
1073 	if (DEBUG(VAR)) {
1074 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name,
1075 		   Buf_GetAll(&v->val, NULL));
1076 	}
1077 
1078 	if (v->flags & VAR_FROM_ENV) {
1079 	    /*
1080 	     * If the original variable came from the environment, we
1081 	     * have to install it in the global context (we could place
1082 	     * it in the environment, but then we should provide a way to
1083 	     * export other variables...)
1084 	     */
1085 	    v->flags &= ~VAR_FROM_ENV;
1086 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
1087 	    Hash_SetValue(h, v);
1088 	}
1089     }
1090     free(expanded_name);
1091 }
1092 
1093 /*-
1094  *-----------------------------------------------------------------------
1095  * Var_Exists --
1096  *	See if the given variable exists.
1097  *
1098  * Input:
1099  *	name		Variable to find
1100  *	ctxt		Context in which to start search
1101  *
1102  * Results:
1103  *	TRUE if it does, FALSE if it doesn't
1104  *
1105  * Side Effects:
1106  *	None.
1107  *
1108  *-----------------------------------------------------------------------
1109  */
1110 Boolean
1111 Var_Exists(const char *name, GNode *ctxt)
1112 {
1113     Var		  *v;
1114     char          *cp;
1115 
1116     if ((cp = strchr(name, '$')) != NULL) {
1117 	cp = Var_Subst(NULL, name, ctxt, VARF_WANTRES);
1118     }
1119     v = VarFind(cp ? cp : name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
1120     free(cp);
1121     if (v == NULL) {
1122 	return(FALSE);
1123     } else {
1124 	(void)VarFreeEnv(v, TRUE);
1125     }
1126     return(TRUE);
1127 }
1128 
1129 /*-
1130  *-----------------------------------------------------------------------
1131  * Var_Value --
1132  *	Return the value of the named variable in the given context
1133  *
1134  * Input:
1135  *	name		name to find
1136  *	ctxt		context in which to search for it
1137  *
1138  * Results:
1139  *	The value if the variable exists, NULL if it doesn't
1140  *
1141  * Side Effects:
1142  *	None
1143  *-----------------------------------------------------------------------
1144  */
1145 char *
1146 Var_Value(const char *name, GNode *ctxt, char **frp)
1147 {
1148     Var            *v;
1149 
1150     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1151     *frp = NULL;
1152     if (v != NULL) {
1153 	char *p = (Buf_GetAll(&v->val, NULL));
1154 	if (VarFreeEnv(v, FALSE))
1155 	    *frp = p;
1156 	return p;
1157     } else {
1158 	return NULL;
1159     }
1160 }
1161 
1162 /*-
1163  *-----------------------------------------------------------------------
1164  * VarHead --
1165  *	Remove the tail of the given word and place the result in the given
1166  *	buffer.
1167  *
1168  * Input:
1169  *	word		Word to trim
1170  *	addSpace	True if need to add a space to the buffer
1171  *			before sticking in the head
1172  *	buf		Buffer in which to store it
1173  *
1174  * Results:
1175  *	TRUE if characters were added to the buffer (a space needs to be
1176  *	added to the buffer before the next word).
1177  *
1178  * Side Effects:
1179  *	The trimmed word is added to the buffer.
1180  *
1181  *-----------------------------------------------------------------------
1182  */
1183 static Boolean
1184 VarHead(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1185 	char *word, Boolean addSpace, Buffer *buf,
1186 	void *dummy MAKE_ATTR_UNUSED)
1187 {
1188     char *slash;
1189 
1190     slash = strrchr(word, '/');
1191     if (slash != NULL) {
1192 	if (addSpace && vpstate->varSpace) {
1193 	    Buf_AddByte(buf, vpstate->varSpace);
1194 	}
1195 	*slash = '\0';
1196 	Buf_AddBytes(buf, strlen(word), word);
1197 	*slash = '/';
1198 	return (TRUE);
1199     } else {
1200 	/*
1201 	 * If no directory part, give . (q.v. the POSIX standard)
1202 	 */
1203 	if (addSpace && vpstate->varSpace)
1204 	    Buf_AddByte(buf, vpstate->varSpace);
1205 	Buf_AddByte(buf, '.');
1206     }
1207     return TRUE;
1208 }
1209 
1210 /*-
1211  *-----------------------------------------------------------------------
1212  * VarTail --
1213  *	Remove the head of the given word and place the result in the given
1214  *	buffer.
1215  *
1216  * Input:
1217  *	word		Word to trim
1218  *	addSpace	True if need to add a space to the buffer
1219  *			before adding the tail
1220  *	buf		Buffer in which to store it
1221  *
1222  * Results:
1223  *	TRUE if characters were added to the buffer (a space needs to be
1224  *	added to the buffer before the next word).
1225  *
1226  * Side Effects:
1227  *	The trimmed word is added to the buffer.
1228  *
1229  *-----------------------------------------------------------------------
1230  */
1231 static Boolean
1232 VarTail(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1233 	char *word, Boolean addSpace, Buffer *buf,
1234 	void *dummy MAKE_ATTR_UNUSED)
1235 {
1236     char *slash;
1237 
1238     if (addSpace && vpstate->varSpace) {
1239 	Buf_AddByte(buf, vpstate->varSpace);
1240     }
1241 
1242     slash = strrchr(word, '/');
1243     if (slash != NULL) {
1244 	*slash++ = '\0';
1245 	Buf_AddBytes(buf, strlen(slash), slash);
1246 	slash[-1] = '/';
1247     } else {
1248 	Buf_AddBytes(buf, strlen(word), word);
1249     }
1250     return TRUE;
1251 }
1252 
1253 /*-
1254  *-----------------------------------------------------------------------
1255  * VarSuffix --
1256  *	Place the suffix of the given word in the given buffer.
1257  *
1258  * Input:
1259  *	word		Word to trim
1260  *	addSpace	TRUE if need to add a space before placing the
1261  *			suffix in the buffer
1262  *	buf		Buffer in which to store it
1263  *
1264  * Results:
1265  *	TRUE if characters were added to the buffer (a space needs to be
1266  *	added to the buffer before the next word).
1267  *
1268  * Side Effects:
1269  *	The suffix from the word is placed in the buffer.
1270  *
1271  *-----------------------------------------------------------------------
1272  */
1273 static Boolean
1274 VarSuffix(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1275 	  char *word, Boolean addSpace, Buffer *buf,
1276 	  void *dummy MAKE_ATTR_UNUSED)
1277 {
1278     char *dot;
1279 
1280     dot = strrchr(word, '.');
1281     if (dot != NULL) {
1282 	if (addSpace && vpstate->varSpace) {
1283 	    Buf_AddByte(buf, vpstate->varSpace);
1284 	}
1285 	*dot++ = '\0';
1286 	Buf_AddBytes(buf, strlen(dot), dot);
1287 	dot[-1] = '.';
1288 	addSpace = TRUE;
1289     }
1290     return addSpace;
1291 }
1292 
1293 /*-
1294  *-----------------------------------------------------------------------
1295  * VarRoot --
1296  *	Remove the suffix of the given word and place the result in the
1297  *	buffer.
1298  *
1299  * Input:
1300  *	word		Word to trim
1301  *	addSpace	TRUE if need to add a space to the buffer
1302  *			before placing the root in it
1303  *	buf		Buffer in which to store it
1304  *
1305  * Results:
1306  *	TRUE if characters were added to the buffer (a space needs to be
1307  *	added to the buffer before the next word).
1308  *
1309  * Side Effects:
1310  *	The trimmed word is added to the buffer.
1311  *
1312  *-----------------------------------------------------------------------
1313  */
1314 static Boolean
1315 VarRoot(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1316 	char *word, Boolean addSpace, Buffer *buf,
1317 	void *dummy MAKE_ATTR_UNUSED)
1318 {
1319     char *dot;
1320 
1321     if (addSpace && vpstate->varSpace) {
1322 	Buf_AddByte(buf, vpstate->varSpace);
1323     }
1324 
1325     dot = strrchr(word, '.');
1326     if (dot != NULL) {
1327 	*dot = '\0';
1328 	Buf_AddBytes(buf, strlen(word), word);
1329 	*dot = '.';
1330     } else {
1331 	Buf_AddBytes(buf, strlen(word), word);
1332     }
1333     return TRUE;
1334 }
1335 
1336 /*-
1337  *-----------------------------------------------------------------------
1338  * VarMatch --
1339  *	Place the word in the buffer if it matches the given pattern.
1340  *	Callback function for VarModify to implement the :M modifier.
1341  *
1342  * Input:
1343  *	word		Word to examine
1344  *	addSpace	TRUE if need to add a space to the buffer
1345  *			before adding the word, if it matches
1346  *	buf		Buffer in which to store it
1347  *	pattern		Pattern the word must match
1348  *
1349  * Results:
1350  *	TRUE if a space should be placed in the buffer before the next
1351  *	word.
1352  *
1353  * Side Effects:
1354  *	The word may be copied to the buffer.
1355  *
1356  *-----------------------------------------------------------------------
1357  */
1358 static Boolean
1359 VarMatch(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1360 	 char *word, Boolean addSpace, Buffer *buf,
1361 	 void *pattern)
1362 {
1363     if (DEBUG(VAR))
1364 	fprintf(debug_file, "VarMatch [%s] [%s]\n", word, (char *)pattern);
1365     if (Str_Match(word, (char *)pattern)) {
1366 	if (addSpace && vpstate->varSpace) {
1367 	    Buf_AddByte(buf, vpstate->varSpace);
1368 	}
1369 	addSpace = TRUE;
1370 	Buf_AddBytes(buf, strlen(word), word);
1371     }
1372     return(addSpace);
1373 }
1374 
1375 #ifdef SYSVVARSUB
1376 /*-
1377  *-----------------------------------------------------------------------
1378  * VarSYSVMatch --
1379  *	Place the word in the buffer if it matches the given pattern.
1380  *	Callback function for VarModify to implement the System V %
1381  *	modifiers.
1382  *
1383  * Input:
1384  *	word		Word to examine
1385  *	addSpace	TRUE if need to add a space to the buffer
1386  *			before adding the word, if it matches
1387  *	buf		Buffer in which to store it
1388  *	patp		Pattern the word must match
1389  *
1390  * Results:
1391  *	TRUE if a space should be placed in the buffer before the next
1392  *	word.
1393  *
1394  * Side Effects:
1395  *	The word may be copied to the buffer.
1396  *
1397  *-----------------------------------------------------------------------
1398  */
1399 static Boolean
1400 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
1401 	     char *word, Boolean addSpace, Buffer *buf,
1402 	     void *patp)
1403 {
1404     int len;
1405     char *ptr;
1406     VarPattern 	  *pat = (VarPattern *)patp;
1407     char *varexp;
1408 
1409     if (addSpace && vpstate->varSpace)
1410 	Buf_AddByte(buf, vpstate->varSpace);
1411 
1412     addSpace = TRUE;
1413 
1414     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
1415         varexp = Var_Subst(NULL, pat->rhs, ctx, VARF_WANTRES);
1416 	Str_SYSVSubst(buf, varexp, ptr, len);
1417 	free(varexp);
1418     } else {
1419 	Buf_AddBytes(buf, strlen(word), word);
1420     }
1421 
1422     return(addSpace);
1423 }
1424 #endif
1425 
1426 
1427 /*-
1428  *-----------------------------------------------------------------------
1429  * VarNoMatch --
1430  *	Place the word in the buffer if it doesn't match the given pattern.
1431  *	Callback function for VarModify to implement the :N modifier.
1432  *
1433  * Input:
1434  *	word		Word to examine
1435  *	addSpace	TRUE if need to add a space to the buffer
1436  *			before adding the word, if it matches
1437  *	buf		Buffer in which to store it
1438  *	pattern		Pattern the word must match
1439  *
1440  * Results:
1441  *	TRUE if a space should be placed in the buffer before the next
1442  *	word.
1443  *
1444  * Side Effects:
1445  *	The word may be copied to the buffer.
1446  *
1447  *-----------------------------------------------------------------------
1448  */
1449 static Boolean
1450 VarNoMatch(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1451 	   char *word, Boolean addSpace, Buffer *buf,
1452 	   void *pattern)
1453 {
1454     if (!Str_Match(word, (char *)pattern)) {
1455 	if (addSpace && vpstate->varSpace) {
1456 	    Buf_AddByte(buf, vpstate->varSpace);
1457 	}
1458 	addSpace = TRUE;
1459 	Buf_AddBytes(buf, strlen(word), word);
1460     }
1461     return(addSpace);
1462 }
1463 
1464 
1465 /*-
1466  *-----------------------------------------------------------------------
1467  * VarSubstitute --
1468  *	Perform a string-substitution on the given word, placing the
1469  *	result in the passed buffer.
1470  *
1471  * Input:
1472  *	word		Word to modify
1473  *	addSpace	True if space should be added before
1474  *			other characters
1475  *	buf		Buffer for result
1476  *	patternp	Pattern for substitution
1477  *
1478  * Results:
1479  *	TRUE if a space is needed before more characters are added.
1480  *
1481  * Side Effects:
1482  *	None.
1483  *
1484  *-----------------------------------------------------------------------
1485  */
1486 static Boolean
1487 VarSubstitute(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1488 	      char *word, Boolean addSpace, Buffer *buf,
1489 	      void *patternp)
1490 {
1491     int  	wordLen;    /* Length of word */
1492     char 	*cp;	    /* General pointer */
1493     VarPattern	*pattern = (VarPattern *)patternp;
1494 
1495     wordLen = strlen(word);
1496     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
1497 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
1498 	/*
1499 	 * Still substituting -- break it down into simple anchored cases
1500 	 * and if none of them fits, perform the general substitution case.
1501 	 */
1502 	if ((pattern->flags & VAR_MATCH_START) &&
1503 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
1504 		/*
1505 		 * Anchored at start and beginning of word matches pattern
1506 		 */
1507 		if ((pattern->flags & VAR_MATCH_END) &&
1508 		    (wordLen == pattern->leftLen)) {
1509 			/*
1510 			 * Also anchored at end and matches to the end (word
1511 			 * is same length as pattern) add space and rhs only
1512 			 * if rhs is non-null.
1513 			 */
1514 			if (pattern->rightLen != 0) {
1515 			    if (addSpace && vpstate->varSpace) {
1516 				Buf_AddByte(buf, vpstate->varSpace);
1517 			    }
1518 			    addSpace = TRUE;
1519 			    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1520 			}
1521 			pattern->flags |= VAR_SUB_MATCHED;
1522 		} else if (pattern->flags & VAR_MATCH_END) {
1523 		    /*
1524 		     * Doesn't match to end -- copy word wholesale
1525 		     */
1526 		    goto nosub;
1527 		} else {
1528 		    /*
1529 		     * Matches at start but need to copy in trailing characters
1530 		     */
1531 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
1532 			if (addSpace && vpstate->varSpace) {
1533 			    Buf_AddByte(buf, vpstate->varSpace);
1534 			}
1535 			addSpace = TRUE;
1536 		    }
1537 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1538 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
1539 				 (word + pattern->leftLen));
1540 		    pattern->flags |= VAR_SUB_MATCHED;
1541 		}
1542 	} else if (pattern->flags & VAR_MATCH_START) {
1543 	    /*
1544 	     * Had to match at start of word and didn't -- copy whole word.
1545 	     */
1546 	    goto nosub;
1547 	} else if (pattern->flags & VAR_MATCH_END) {
1548 	    /*
1549 	     * Anchored at end, Find only place match could occur (leftLen
1550 	     * characters from the end of the word) and see if it does. Note
1551 	     * that because the $ will be left at the end of the lhs, we have
1552 	     * to use strncmp.
1553 	     */
1554 	    cp = word + (wordLen - pattern->leftLen);
1555 	    if ((cp >= word) &&
1556 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
1557 		/*
1558 		 * Match found. If we will place characters in the buffer,
1559 		 * add a space before hand as indicated by addSpace, then
1560 		 * stuff in the initial, unmatched part of the word followed
1561 		 * by the right-hand-side.
1562 		 */
1563 		if (((cp - word) + pattern->rightLen) != 0) {
1564 		    if (addSpace && vpstate->varSpace) {
1565 			Buf_AddByte(buf, vpstate->varSpace);
1566 		    }
1567 		    addSpace = TRUE;
1568 		}
1569 		Buf_AddBytes(buf, cp - word, word);
1570 		Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1571 		pattern->flags |= VAR_SUB_MATCHED;
1572 	    } else {
1573 		/*
1574 		 * Had to match at end and didn't. Copy entire word.
1575 		 */
1576 		goto nosub;
1577 	    }
1578 	} else {
1579 	    /*
1580 	     * Pattern is unanchored: search for the pattern in the word using
1581 	     * String_FindSubstring, copying unmatched portions and the
1582 	     * right-hand-side for each match found, handling non-global
1583 	     * substitutions correctly, etc. When the loop is done, any
1584 	     * remaining part of the word (word and wordLen are adjusted
1585 	     * accordingly through the loop) is copied straight into the
1586 	     * buffer.
1587 	     * addSpace is set FALSE as soon as a space is added to the
1588 	     * buffer.
1589 	     */
1590 	    Boolean done;
1591 	    int origSize;
1592 
1593 	    done = FALSE;
1594 	    origSize = Buf_Size(buf);
1595 	    while (!done) {
1596 		cp = Str_FindSubstring(word, pattern->lhs);
1597 		if (cp != NULL) {
1598 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
1599 			Buf_AddByte(buf, vpstate->varSpace);
1600 			addSpace = FALSE;
1601 		    }
1602 		    Buf_AddBytes(buf, cp-word, word);
1603 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1604 		    wordLen -= (cp - word) + pattern->leftLen;
1605 		    word = cp + pattern->leftLen;
1606 		    if (wordLen == 0) {
1607 			done = TRUE;
1608 		    }
1609 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
1610 			done = TRUE;
1611 		    }
1612 		    pattern->flags |= VAR_SUB_MATCHED;
1613 		} else {
1614 		    done = TRUE;
1615 		}
1616 	    }
1617 	    if (wordLen != 0) {
1618 		if (addSpace && vpstate->varSpace) {
1619 		    Buf_AddByte(buf, vpstate->varSpace);
1620 		}
1621 		Buf_AddBytes(buf, wordLen, word);
1622 	    }
1623 	    /*
1624 	     * If added characters to the buffer, need to add a space
1625 	     * before we add any more. If we didn't add any, just return
1626 	     * the previous value of addSpace.
1627 	     */
1628 	    return ((Buf_Size(buf) != origSize) || addSpace);
1629 	}
1630 	return (addSpace);
1631     }
1632  nosub:
1633     if (addSpace && vpstate->varSpace) {
1634 	Buf_AddByte(buf, vpstate->varSpace);
1635     }
1636     Buf_AddBytes(buf, wordLen, word);
1637     return(TRUE);
1638 }
1639 
1640 #ifndef NO_REGEX
1641 /*-
1642  *-----------------------------------------------------------------------
1643  * VarREError --
1644  *	Print the error caused by a regcomp or regexec call.
1645  *
1646  * Results:
1647  *	None.
1648  *
1649  * Side Effects:
1650  *	An error gets printed.
1651  *
1652  *-----------------------------------------------------------------------
1653  */
1654 static void
1655 VarREError(int reerr, regex_t *pat, const char *str)
1656 {
1657     char *errbuf;
1658     int errlen;
1659 
1660     errlen = regerror(reerr, pat, 0, 0);
1661     errbuf = bmake_malloc(errlen);
1662     regerror(reerr, pat, errbuf, errlen);
1663     Error("%s: %s", str, errbuf);
1664     free(errbuf);
1665 }
1666 
1667 
1668 /*-
1669  *-----------------------------------------------------------------------
1670  * VarRESubstitute --
1671  *	Perform a regex substitution on the given word, placing the
1672  *	result in the passed buffer.
1673  *
1674  * Results:
1675  *	TRUE if a space is needed before more characters are added.
1676  *
1677  * Side Effects:
1678  *	None.
1679  *
1680  *-----------------------------------------------------------------------
1681  */
1682 static Boolean
1683 VarRESubstitute(GNode *ctx MAKE_ATTR_UNUSED,
1684 		Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
1685 		char *word, Boolean addSpace, Buffer *buf,
1686 		void *patternp)
1687 {
1688     VarREPattern *pat;
1689     int xrv;
1690     char *wp;
1691     char *rp;
1692     int added;
1693     int flags = 0;
1694 
1695 #define MAYBE_ADD_SPACE()		\
1696 	if (addSpace && !added)		\
1697 	    Buf_AddByte(buf, ' ');	\
1698 	added = 1
1699 
1700     added = 0;
1701     wp = word;
1702     pat = patternp;
1703 
1704     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1705 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1706 	xrv = REG_NOMATCH;
1707     else {
1708     tryagain:
1709 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1710     }
1711 
1712     switch (xrv) {
1713     case 0:
1714 	pat->flags |= VAR_SUB_MATCHED;
1715 	if (pat->matches[0].rm_so > 0) {
1716 	    MAYBE_ADD_SPACE();
1717 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1718 	}
1719 
1720 	for (rp = pat->replace; *rp; rp++) {
1721 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1722 		MAYBE_ADD_SPACE();
1723 		Buf_AddByte(buf,rp[1]);
1724 		rp++;
1725 	    }
1726 	    else if ((*rp == '&') ||
1727 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1728 		int n;
1729 		const char *subbuf;
1730 		int sublen;
1731 		char errstr[3];
1732 
1733 		if (*rp == '&') {
1734 		    n = 0;
1735 		    errstr[0] = '&';
1736 		    errstr[1] = '\0';
1737 		} else {
1738 		    n = rp[1] - '0';
1739 		    errstr[0] = '\\';
1740 		    errstr[1] = rp[1];
1741 		    errstr[2] = '\0';
1742 		    rp++;
1743 		}
1744 
1745 		if (n > pat->nsub) {
1746 		    Error("No subexpression %s", &errstr[0]);
1747 		    subbuf = "";
1748 		    sublen = 0;
1749 		} else if ((pat->matches[n].rm_so == -1) &&
1750 			   (pat->matches[n].rm_eo == -1)) {
1751 		    Error("No match for subexpression %s", &errstr[0]);
1752 		    subbuf = "";
1753 		    sublen = 0;
1754 	        } else {
1755 		    subbuf = wp + pat->matches[n].rm_so;
1756 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1757 		}
1758 
1759 		if (sublen > 0) {
1760 		    MAYBE_ADD_SPACE();
1761 		    Buf_AddBytes(buf, sublen, subbuf);
1762 		}
1763 	    } else {
1764 		MAYBE_ADD_SPACE();
1765 		Buf_AddByte(buf, *rp);
1766 	    }
1767 	}
1768 	wp += pat->matches[0].rm_eo;
1769 	if (pat->flags & VAR_SUB_GLOBAL) {
1770 	    flags |= REG_NOTBOL;
1771 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1772 		MAYBE_ADD_SPACE();
1773 		Buf_AddByte(buf, *wp);
1774 		wp++;
1775 
1776 	    }
1777 	    if (*wp)
1778 		goto tryagain;
1779 	}
1780 	if (*wp) {
1781 	    MAYBE_ADD_SPACE();
1782 	    Buf_AddBytes(buf, strlen(wp), wp);
1783 	}
1784 	break;
1785     default:
1786 	VarREError(xrv, &pat->re, "Unexpected regex error");
1787        /* fall through */
1788     case REG_NOMATCH:
1789 	if (*wp) {
1790 	    MAYBE_ADD_SPACE();
1791 	    Buf_AddBytes(buf,strlen(wp),wp);
1792 	}
1793 	break;
1794     }
1795     return(addSpace||added);
1796 }
1797 #endif
1798 
1799 
1800 
1801 /*-
1802  *-----------------------------------------------------------------------
1803  * VarLoopExpand --
1804  *	Implements the :@<temp>@<string>@ modifier of ODE make.
1805  *	We set the temp variable named in pattern.lhs to word and expand
1806  *	pattern.rhs storing the result in the passed buffer.
1807  *
1808  * Input:
1809  *	word		Word to modify
1810  *	addSpace	True if space should be added before
1811  *			other characters
1812  *	buf		Buffer for result
1813  *	pattern		Datafor substitution
1814  *
1815  * Results:
1816  *	TRUE if a space is needed before more characters are added.
1817  *
1818  * Side Effects:
1819  *	None.
1820  *
1821  *-----------------------------------------------------------------------
1822  */
1823 static Boolean
1824 VarLoopExpand(GNode *ctx MAKE_ATTR_UNUSED,
1825 	      Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
1826 	      char *word, Boolean addSpace, Buffer *buf,
1827 	      void *loopp)
1828 {
1829     VarLoop_t	*loop = (VarLoop_t *)loopp;
1830     char *s;
1831     int slen;
1832 
1833     if (word && *word) {
1834         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
1835         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->errnum | VARF_WANTRES);
1836         if (s != NULL && *s != '\0') {
1837             if (addSpace && *s != '\n')
1838                 Buf_AddByte(buf, ' ');
1839             Buf_AddBytes(buf, (slen = strlen(s)), s);
1840             addSpace = (slen > 0 && s[slen - 1] != '\n');
1841         }
1842 	free(s);
1843     }
1844     return addSpace;
1845 }
1846 
1847 
1848 /*-
1849  *-----------------------------------------------------------------------
1850  * VarSelectWords --
1851  *	Implements the :[start..end] modifier.
1852  *	This is a special case of VarModify since we want to be able
1853  *	to scan the list backwards if start > end.
1854  *
1855  * Input:
1856  *	str		String whose words should be trimmed
1857  *	seldata		words to select
1858  *
1859  * Results:
1860  *	A string of all the words selected.
1861  *
1862  * Side Effects:
1863  *	None.
1864  *
1865  *-----------------------------------------------------------------------
1866  */
1867 static char *
1868 VarSelectWords(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1869 	       const char *str, VarSelectWords_t *seldata)
1870 {
1871     Buffer  	  buf;		    /* Buffer for the new string */
1872     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1873 				     * buffer before adding the trimmed
1874 				     * word */
1875     char **av;			    /* word list */
1876     char *as;			    /* word list memory */
1877     int ac, i;
1878     int start, end, step;
1879 
1880     Buf_Init(&buf, 0);
1881     addSpace = FALSE;
1882 
1883     if (vpstate->oneBigWord) {
1884 	/* fake what brk_string() would do if there were only one word */
1885 	ac = 1;
1886     	av = bmake_malloc((ac + 1) * sizeof(char *));
1887 	as = bmake_strdup(str);
1888 	av[0] = as;
1889 	av[1] = NULL;
1890     } else {
1891 	av = brk_string(str, &ac, FALSE, &as);
1892     }
1893 
1894     /*
1895      * Now sanitize seldata.
1896      * If seldata->start or seldata->end are negative, convert them to
1897      * the positive equivalents (-1 gets converted to argc, -2 gets
1898      * converted to (argc-1), etc.).
1899      */
1900     if (seldata->start < 0)
1901 	seldata->start = ac + seldata->start + 1;
1902     if (seldata->end < 0)
1903 	seldata->end = ac + seldata->end + 1;
1904 
1905     /*
1906      * We avoid scanning more of the list than we need to.
1907      */
1908     if (seldata->start > seldata->end) {
1909 	start = MIN(ac, seldata->start) - 1;
1910 	end = MAX(0, seldata->end - 1);
1911 	step = -1;
1912     } else {
1913 	start = MAX(0, seldata->start - 1);
1914 	end = MIN(ac, seldata->end);
1915 	step = 1;
1916     }
1917 
1918     for (i = start;
1919 	 (step < 0 && i >= end) || (step > 0 && i < end);
1920 	 i += step) {
1921 	if (av[i] && *av[i]) {
1922 	    if (addSpace && vpstate->varSpace) {
1923 		Buf_AddByte(&buf, vpstate->varSpace);
1924 	    }
1925 	    Buf_AddBytes(&buf, strlen(av[i]), av[i]);
1926 	    addSpace = TRUE;
1927 	}
1928     }
1929 
1930     free(as);
1931     free(av);
1932 
1933     return Buf_Destroy(&buf, FALSE);
1934 }
1935 
1936 
1937 /*-
1938  * VarRealpath --
1939  *	Replace each word with the result of realpath()
1940  *	if successful.
1941  */
1942 static Boolean
1943 VarRealpath(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1944 	    char *word, Boolean addSpace, Buffer *buf,
1945 	    void *patternp MAKE_ATTR_UNUSED)
1946 {
1947 	struct stat st;
1948 	char rbuf[MAXPATHLEN];
1949 	char *rp;
1950 
1951 	if (addSpace && vpstate->varSpace) {
1952 	    Buf_AddByte(buf, vpstate->varSpace);
1953 	}
1954 	addSpace = TRUE;
1955 	rp = cached_realpath(word, rbuf);
1956 	if (rp && *rp == '/' && stat(rp, &st) == 0)
1957 		word = rp;
1958 
1959 	Buf_AddBytes(buf, strlen(word), word);
1960 	return(addSpace);
1961 }
1962 
1963 /*-
1964  *-----------------------------------------------------------------------
1965  * VarModify --
1966  *	Modify each of the words of the passed string using the given
1967  *	function. Used to implement all modifiers.
1968  *
1969  * Input:
1970  *	str		String whose words should be trimmed
1971  *	modProc		Function to use to modify them
1972  *	datum		Datum to pass it
1973  *
1974  * Results:
1975  *	A string of all the words modified appropriately.
1976  *
1977  * Side Effects:
1978  *	None.
1979  *
1980  *-----------------------------------------------------------------------
1981  */
1982 static char *
1983 VarModify(GNode *ctx, Var_Parse_State *vpstate,
1984     const char *str,
1985     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
1986 		       Boolean, Buffer *, void *),
1987     void *datum)
1988 {
1989     Buffer  	  buf;		    /* Buffer for the new string */
1990     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1991 				     * buffer before adding the trimmed
1992 				     * word */
1993     char **av;			    /* word list */
1994     char *as;			    /* word list memory */
1995     int ac, i;
1996 
1997     Buf_Init(&buf, 0);
1998     addSpace = FALSE;
1999 
2000     if (vpstate->oneBigWord) {
2001 	/* fake what brk_string() would do if there were only one word */
2002 	ac = 1;
2003     	av = bmake_malloc((ac + 1) * sizeof(char *));
2004 	as = bmake_strdup(str);
2005 	av[0] = as;
2006 	av[1] = NULL;
2007     } else {
2008 	av = brk_string(str, &ac, FALSE, &as);
2009     }
2010 
2011     for (i = 0; i < ac; i++) {
2012 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, &buf, datum);
2013     }
2014 
2015     free(as);
2016     free(av);
2017 
2018     return Buf_Destroy(&buf, FALSE);
2019 }
2020 
2021 
2022 static int
2023 VarWordCompare(const void *a, const void *b)
2024 {
2025 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
2026 	return r;
2027 }
2028 
2029 /*-
2030  *-----------------------------------------------------------------------
2031  * VarOrder --
2032  *	Order the words in the string.
2033  *
2034  * Input:
2035  *	str		String whose words should be sorted.
2036  *	otype		How to order: s - sort, x - random.
2037  *
2038  * Results:
2039  *	A string containing the words ordered.
2040  *
2041  * Side Effects:
2042  *	None.
2043  *
2044  *-----------------------------------------------------------------------
2045  */
2046 static char *
2047 VarOrder(const char *str, const char otype)
2048 {
2049     Buffer  	  buf;		    /* Buffer for the new string */
2050     char **av;			    /* word list [first word does not count] */
2051     char *as;			    /* word list memory */
2052     int ac, i;
2053 
2054     Buf_Init(&buf, 0);
2055 
2056     av = brk_string(str, &ac, FALSE, &as);
2057 
2058     if (ac > 0)
2059 	switch (otype) {
2060 	case 's':	/* sort alphabetically */
2061 	    qsort(av, ac, sizeof(char *), VarWordCompare);
2062 	    break;
2063 	case 'x':	/* randomize */
2064 	{
2065 	    int rndidx;
2066 	    char *t;
2067 
2068 	    /*
2069 	     * We will use [ac..2] range for mod factors. This will produce
2070 	     * random numbers in [(ac-1)..0] interval, and minimal
2071 	     * reasonable value for mod factor is 2 (the mod 1 will produce
2072 	     * 0 with probability 1).
2073 	     */
2074 	    for (i = ac-1; i > 0; i--) {
2075 		rndidx = random() % (i + 1);
2076 		if (i != rndidx) {
2077 		    t = av[i];
2078 		    av[i] = av[rndidx];
2079 		    av[rndidx] = t;
2080 		}
2081 	    }
2082 	}
2083 	} /* end of switch */
2084 
2085     for (i = 0; i < ac; i++) {
2086 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
2087 	if (i != ac - 1)
2088 	    Buf_AddByte(&buf, ' ');
2089     }
2090 
2091     free(as);
2092     free(av);
2093 
2094     return Buf_Destroy(&buf, FALSE);
2095 }
2096 
2097 
2098 /*-
2099  *-----------------------------------------------------------------------
2100  * VarUniq --
2101  *	Remove adjacent duplicate words.
2102  *
2103  * Input:
2104  *	str		String whose words should be sorted
2105  *
2106  * Results:
2107  *	A string containing the resulting words.
2108  *
2109  * Side Effects:
2110  *	None.
2111  *
2112  *-----------------------------------------------------------------------
2113  */
2114 static char *
2115 VarUniq(const char *str)
2116 {
2117     Buffer	  buf;		    /* Buffer for new string */
2118     char 	**av;		    /* List of words to affect */
2119     char 	 *as;		    /* Word list memory */
2120     int 	  ac, i, j;
2121 
2122     Buf_Init(&buf, 0);
2123     av = brk_string(str, &ac, FALSE, &as);
2124 
2125     if (ac > 1) {
2126 	for (j = 0, i = 1; i < ac; i++)
2127 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
2128 		av[j] = av[i];
2129 	ac = j + 1;
2130     }
2131 
2132     for (i = 0; i < ac; i++) {
2133 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
2134 	if (i != ac - 1)
2135 	    Buf_AddByte(&buf, ' ');
2136     }
2137 
2138     free(as);
2139     free(av);
2140 
2141     return Buf_Destroy(&buf, FALSE);
2142 }
2143 
2144 /*-
2145  *-----------------------------------------------------------------------
2146  * VarRange --
2147  *	Return an integer sequence
2148  *
2149  * Input:
2150  *	str		String whose words provide default range
2151  *	ac		range length, if 0 use str words
2152  *
2153  * Side Effects:
2154  *	None.
2155  *
2156  *-----------------------------------------------------------------------
2157  */
2158 static char *
2159 VarRange(const char *str, int ac)
2160 {
2161     Buffer	  buf;		    /* Buffer for new string */
2162     char	  tmp[32];	    /* each element */
2163     char 	**av;		    /* List of words to affect */
2164     char 	 *as;		    /* Word list memory */
2165     int 	  i, n;
2166 
2167     Buf_Init(&buf, 0);
2168     if (ac > 0) {
2169 	as = NULL;
2170 	av = NULL;
2171     } else {
2172 	av = brk_string(str, &ac, FALSE, &as);
2173     }
2174     for (i = 0; i < ac; i++) {
2175 	n = snprintf(tmp, sizeof(tmp), "%d", 1 + i);
2176 	if (n >= (int)sizeof(tmp))
2177 	    break;
2178 	Buf_AddBytes(&buf, n, tmp);
2179 	if (i != ac - 1)
2180 	    Buf_AddByte(&buf, ' ');
2181     }
2182 
2183     free(as);
2184     free(av);
2185 
2186     return Buf_Destroy(&buf, FALSE);
2187 }
2188 
2189 
2190 /*-
2191  *-----------------------------------------------------------------------
2192  * VarGetPattern --
2193  *	Pass through the tstr looking for 1) escaped delimiters,
2194  *	'$'s and backslashes (place the escaped character in
2195  *	uninterpreted) and 2) unescaped $'s that aren't before
2196  *	the delimiter (expand the variable substitution unless flags
2197  *	has VAR_NOSUBST set).
2198  *	Return the expanded string or NULL if the delimiter was missing
2199  *	If pattern is specified, handle escaped ampersands, and replace
2200  *	unescaped ampersands with the lhs of the pattern.
2201  *
2202  * Results:
2203  *	A string of all the words modified appropriately.
2204  *	If length is specified, return the string length of the buffer
2205  *	If flags is specified and the last character of the pattern is a
2206  *	$ set the VAR_MATCH_END bit of flags.
2207  *
2208  * Side Effects:
2209  *	None.
2210  *-----------------------------------------------------------------------
2211  */
2212 static char *
2213 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
2214 	      int flags, const char **tstr, int delim, int *vflags,
2215 	      int *length, VarPattern *pattern)
2216 {
2217     const char *cp;
2218     char *rstr;
2219     Buffer buf;
2220     int junk;
2221     int errnum = flags & VARF_UNDEFERR;
2222 
2223     Buf_Init(&buf, 0);
2224     if (length == NULL)
2225 	length = &junk;
2226 
2227 #define IS_A_MATCH(cp, delim) \
2228     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
2229      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
2230 
2231     /*
2232      * Skim through until the matching delimiter is found;
2233      * pick up variable substitutions on the way. Also allow
2234      * backslashes to quote the delimiter, $, and \, but don't
2235      * touch other backslashes.
2236      */
2237     for (cp = *tstr; *cp && (*cp != delim); cp++) {
2238 	if (IS_A_MATCH(cp, delim)) {
2239 	    Buf_AddByte(&buf, cp[1]);
2240 	    cp++;
2241 	} else if (*cp == '$') {
2242 	    if (cp[1] == delim) {
2243 		if (vflags == NULL)
2244 		    Buf_AddByte(&buf, *cp);
2245 		else
2246 		    /*
2247 		     * Unescaped $ at end of pattern => anchor
2248 		     * pattern at end.
2249 		     */
2250 		    *vflags |= VAR_MATCH_END;
2251 	    } else {
2252 		if (vflags == NULL || (*vflags & VAR_NOSUBST) == 0) {
2253 		    char   *cp2;
2254 		    int     len;
2255 		    void   *freeIt;
2256 
2257 		    /*
2258 		     * If unescaped dollar sign not before the
2259 		     * delimiter, assume it's a variable
2260 		     * substitution and recurse.
2261 		     */
2262 		    cp2 = Var_Parse(cp, ctxt, errnum | VARF_WANTRES, &len,
2263 			&freeIt);
2264 		    Buf_AddBytes(&buf, strlen(cp2), cp2);
2265 		    free(freeIt);
2266 		    cp += len - 1;
2267 		} else {
2268 		    const char *cp2 = &cp[1];
2269 
2270 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
2271 			/*
2272 			 * Find the end of this variable reference
2273 			 * and suck it in without further ado.
2274 			 * It will be interperated later.
2275 			 */
2276 			int have = *cp2;
2277 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
2278 			int depth = 1;
2279 
2280 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
2281 			    if (cp2[-1] != '\\') {
2282 				if (*cp2 == have)
2283 				    ++depth;
2284 				if (*cp2 == want)
2285 				    --depth;
2286 			    }
2287 			}
2288 			Buf_AddBytes(&buf, cp2 - cp, cp);
2289 			cp = --cp2;
2290 		    } else
2291 			Buf_AddByte(&buf, *cp);
2292 		}
2293 	    }
2294 	}
2295 	else if (pattern && *cp == '&')
2296 	    Buf_AddBytes(&buf, pattern->leftLen, pattern->lhs);
2297 	else
2298 	    Buf_AddByte(&buf, *cp);
2299     }
2300 
2301     if (*cp != delim) {
2302 	*tstr = cp;
2303 	*length = 0;
2304 	return NULL;
2305     }
2306 
2307     *tstr = ++cp;
2308     *length = Buf_Size(&buf);
2309     rstr = Buf_Destroy(&buf, FALSE);
2310     if (DEBUG(VAR))
2311 	fprintf(debug_file, "Modifier pattern: \"%s\"\n", rstr);
2312     return rstr;
2313 }
2314 
2315 /*-
2316  *-----------------------------------------------------------------------
2317  * VarQuote --
2318  *	Quote shell meta-characters and space characters in the string
2319  *	if quoteDollar is set, also quote and double any '$' characters.
2320  *
2321  * Results:
2322  *	The quoted string
2323  *
2324  * Side Effects:
2325  *	None.
2326  *
2327  *-----------------------------------------------------------------------
2328  */
2329 static char *
2330 VarQuote(char *str, Boolean quoteDollar)
2331 {
2332 
2333     Buffer  	  buf;
2334     const char	*newline;
2335     size_t nlen;
2336 
2337     if ((newline = Shell_GetNewline()) == NULL)
2338 	    newline = "\\\n";
2339     nlen = strlen(newline);
2340 
2341     Buf_Init(&buf, 0);
2342 
2343     for (; *str != '\0'; str++) {
2344 	if (*str == '\n') {
2345 	    Buf_AddBytes(&buf, nlen, newline);
2346 	    continue;
2347 	}
2348 	if (isspace((unsigned char)*str) || ismeta((unsigned char)*str))
2349 	    Buf_AddByte(&buf, '\\');
2350 	Buf_AddByte(&buf, *str);
2351 	if (quoteDollar && *str == '$')
2352 	    Buf_AddBytes(&buf, 2, "\\$");
2353     }
2354 
2355     str = Buf_Destroy(&buf, FALSE);
2356     if (DEBUG(VAR))
2357 	fprintf(debug_file, "QuoteMeta: [%s]\n", str);
2358     return str;
2359 }
2360 
2361 /*-
2362  *-----------------------------------------------------------------------
2363  * VarHash --
2364  *      Hash the string using the MurmurHash3 algorithm.
2365  *      Output is computed using 32bit Little Endian arithmetic.
2366  *
2367  * Input:
2368  *	str		String to modify
2369  *
2370  * Results:
2371  *      Hash value of str, encoded as 8 hex digits.
2372  *
2373  * Side Effects:
2374  *      None.
2375  *
2376  *-----------------------------------------------------------------------
2377  */
2378 static char *
2379 VarHash(char *str)
2380 {
2381     static const char    hexdigits[16] = "0123456789abcdef";
2382     Buffer         buf;
2383     size_t         len, len2;
2384     unsigned char  *ustr = (unsigned char *)str;
2385     unsigned int   h, k, c1, c2;
2386 
2387     h  = 0x971e137bU;
2388     c1 = 0x95543787U;
2389     c2 = 0x2ad7eb25U;
2390     len2 = strlen(str);
2391 
2392     for (len = len2; len; ) {
2393 	k = 0;
2394 	switch (len) {
2395 	default:
2396 	    k = (ustr[3] << 24) | (ustr[2] << 16) | (ustr[1] << 8) | ustr[0];
2397 	    len -= 4;
2398 	    ustr += 4;
2399 	    break;
2400 	case 3:
2401 	    k |= (ustr[2] << 16);
2402 	case 2:
2403 	    k |= (ustr[1] << 8);
2404 	case 1:
2405 	    k |= ustr[0];
2406 	    len = 0;
2407 	}
2408 	c1 = c1 * 5 + 0x7b7d159cU;
2409 	c2 = c2 * 5 + 0x6bce6396U;
2410 	k *= c1;
2411 	k = (k << 11) ^ (k >> 21);
2412 	k *= c2;
2413 	h = (h << 13) ^ (h >> 19);
2414 	h = h * 5 + 0x52dce729U;
2415 	h ^= k;
2416    }
2417    h ^= len2;
2418    h *= 0x85ebca6b;
2419    h ^= h >> 13;
2420    h *= 0xc2b2ae35;
2421    h ^= h >> 16;
2422 
2423    Buf_Init(&buf, 0);
2424    for (len = 0; len < 8; ++len) {
2425        Buf_AddByte(&buf, hexdigits[h & 15]);
2426        h >>= 4;
2427    }
2428 
2429    return Buf_Destroy(&buf, FALSE);
2430 }
2431 
2432 static char *
2433 VarStrftime(const char *fmt, int zulu, time_t utc)
2434 {
2435     char buf[BUFSIZ];
2436 
2437     if (!utc)
2438 	time(&utc);
2439     if (!*fmt)
2440 	fmt = "%c";
2441     strftime(buf, sizeof(buf), fmt, zulu ? gmtime(&utc) : localtime(&utc));
2442 
2443     buf[sizeof(buf) - 1] = '\0';
2444     return bmake_strdup(buf);
2445 }
2446 
2447 /*
2448  * Now we need to apply any modifiers the user wants applied.
2449  * These are:
2450  *  	  :M<pattern>	words which match the given <pattern>.
2451  *  			<pattern> is of the standard file
2452  *  			wildcarding form.
2453  *  	  :N<pattern>	words which do not match the given <pattern>.
2454  *  	  :S<d><pat1><d><pat2><d>[1gW]
2455  *  			Substitute <pat2> for <pat1> in the value
2456  *  	  :C<d><pat1><d><pat2><d>[1gW]
2457  *  			Substitute <pat2> for regex <pat1> in the value
2458  *  	  :H		Substitute the head of each word
2459  *  	  :T		Substitute the tail of each word
2460  *  	  :E		Substitute the extension (minus '.') of
2461  *  			each word
2462  *  	  :R		Substitute the root of each word
2463  *  			(pathname minus the suffix).
2464  *	  :O		("Order") Alphabeticaly sort words in variable.
2465  *	  :Ox		("intermiX") Randomize words in variable.
2466  *	  :u		("uniq") Remove adjacent duplicate words.
2467  *	  :tu		Converts the variable contents to uppercase.
2468  *	  :tl		Converts the variable contents to lowercase.
2469  *	  :ts[c]	Sets varSpace - the char used to
2470  *			separate words to 'c'. If 'c' is
2471  *			omitted then no separation is used.
2472  *	  :tW		Treat the variable contents as a single
2473  *			word, even if it contains spaces.
2474  *			(Mnemonic: one big 'W'ord.)
2475  *	  :tw		Treat the variable contents as multiple
2476  *			space-separated words.
2477  *			(Mnemonic: many small 'w'ords.)
2478  *	  :[index]	Select a single word from the value.
2479  *	  :[start..end]	Select multiple words from the value.
2480  *	  :[*] or :[0]	Select the entire value, as a single
2481  *			word.  Equivalent to :tW.
2482  *	  :[@]		Select the entire value, as multiple
2483  *			words.	Undoes the effect of :[*].
2484  *			Equivalent to :tw.
2485  *	  :[#]		Returns the number of words in the value.
2486  *
2487  *	  :?<true-value>:<false-value>
2488  *			If the variable evaluates to true, return
2489  *			true value, else return the second value.
2490  *    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
2491  *    			the invocation.
2492  *	  :sh		Treat the current value as a command
2493  *			to be run, new value is its output.
2494  * The following added so we can handle ODE makefiles.
2495  *	  :@<tmpvar>@<newval>@
2496  *			Assign a temporary local variable <tmpvar>
2497  *			to the current value of each word in turn
2498  *			and replace each word with the result of
2499  *			evaluating <newval>
2500  *	  :D<newval>	Use <newval> as value if variable defined
2501  *	  :U<newval>	Use <newval> as value if variable undefined
2502  *	  :L		Use the name of the variable as the value.
2503  *	  :P		Use the path of the node that has the same
2504  *			name as the variable as the value.  This
2505  *			basically includes an implied :L so that
2506  *			the common method of refering to the path
2507  *			of your dependent 'x' in a rule is to use
2508  *			the form '${x:P}'.
2509  *	  :!<cmd>!	Run cmd much the same as :sh run's the
2510  *			current value of the variable.
2511  * The ::= modifiers, actually assign a value to the variable.
2512  * Their main purpose is in supporting modifiers of .for loop
2513  * iterators and other obscure uses.  They always expand to
2514  * nothing.  In a target rule that would otherwise expand to an
2515  * empty line they can be preceded with @: to keep make happy.
2516  * Eg.
2517  *
2518  * foo:	.USE
2519  * .for i in ${.TARGET} ${.TARGET:R}.gz
2520  * 	@: ${t::=$i}
2521  *	@echo blah ${t:T}
2522  * .endfor
2523  *
2524  *	  ::=<str>	Assigns <str> as the new value of variable.
2525  *	  ::?=<str>	Assigns <str> as value of variable if
2526  *			it was not already set.
2527  *	  ::+=<str>	Appends <str> to variable.
2528  *	  ::!=<cmd>	Assigns output of <cmd> as the new value of
2529  *			variable.
2530  */
2531 
2532 /* we now have some modifiers with long names */
2533 #define STRMOD_MATCH(s, want, n) \
2534     (strncmp(s, want, n) == 0 && (s[n] == endc || s[n] == ':'))
2535 #define STRMOD_MATCHX(s, want, n) \
2536     (strncmp(s, want, n) == 0 && (s[n] == endc || s[n] == ':' || s[n] == '='))
2537 #define CHARMOD_MATCH(c) (c == endc || c == ':')
2538 
2539 static char *
2540 ApplyModifiers(char *nstr, const char *tstr,
2541 	       int startc, int endc,
2542 	       Var *v, GNode *ctxt, int flags,
2543 	       int *lengthPtr, void **freePtr)
2544 {
2545     const char 	   *start;
2546     const char     *cp;    	/* Secondary pointer into str (place marker
2547 				 * for tstr) */
2548     char	   *newStr;	/* New value to return */
2549     char	   *ep;
2550     char	    termc;	/* Character which terminated scan */
2551     int             cnt;	/* Used to count brace pairs when variable in
2552 				 * in parens or braces */
2553     char	delim;
2554     int		modifier;	/* that we are processing */
2555     Var_Parse_State parsestate; /* Flags passed to helper functions */
2556     time_t	utc;		/* for VarStrftime */
2557 
2558     delim = '\0';
2559     parsestate.oneBigWord = FALSE;
2560     parsestate.varSpace = ' ';	/* word separator */
2561 
2562     start = cp = tstr;
2563 
2564     while (*tstr && *tstr != endc) {
2565 
2566 	if (*tstr == '$') {
2567 	    /*
2568 	     * We may have some complex modifiers in a variable.
2569 	     */
2570 	    void *freeIt;
2571 	    char *rval;
2572 	    int rlen;
2573 	    int c;
2574 
2575 	    rval = Var_Parse(tstr, ctxt, flags, &rlen, &freeIt);
2576 
2577 	    /*
2578 	     * If we have not parsed up to endc or ':',
2579 	     * we are not interested.
2580 	     */
2581 	    if (rval != NULL && *rval &&
2582 		(c = tstr[rlen]) != '\0' &&
2583 		c != ':' &&
2584 		c != endc) {
2585 		free(freeIt);
2586 		goto apply_mods;
2587 	    }
2588 
2589 	    if (DEBUG(VAR)) {
2590 		fprintf(debug_file, "Got '%s' from '%.*s'%.*s\n",
2591 		       rval, rlen, tstr, rlen, tstr + rlen);
2592 	    }
2593 
2594 	    tstr += rlen;
2595 
2596 	    if (rval != NULL && *rval) {
2597 		int used;
2598 
2599 		nstr = ApplyModifiers(nstr, rval,
2600 				      0, 0, v, ctxt, flags, &used, freePtr);
2601 		if (nstr == var_Error
2602 		    || (nstr == varNoError && (flags & VARF_UNDEFERR) == 0)
2603 		    || strlen(rval) != (size_t) used) {
2604 		    free(freeIt);
2605 		    goto out;		/* error already reported */
2606 		}
2607 	    }
2608 	    free(freeIt);
2609 	    if (*tstr == ':')
2610 		tstr++;
2611 	    else if (!*tstr && endc) {
2612 		Error("Unclosed variable specification after complex modifier (expecting '%c') for %s", endc, v->name);
2613 		goto out;
2614 	    }
2615 	    continue;
2616 	}
2617     apply_mods:
2618 	if (DEBUG(VAR)) {
2619 	    fprintf(debug_file, "Applying[%s] :%c to \"%s\"\n", v->name,
2620 		*tstr, nstr);
2621 	}
2622 	newStr = var_Error;
2623 	switch ((modifier = *tstr)) {
2624 	case ':':
2625 	    {
2626 		if (tstr[1] == '=' ||
2627 		    (tstr[2] == '=' &&
2628 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
2629 		    /*
2630 		     * "::=", "::!=", "::+=", or "::?="
2631 		     */
2632 		    GNode *v_ctxt;		/* context where v belongs */
2633 		    const char *emsg;
2634 		    char *sv_name;
2635 		    VarPattern	pattern;
2636 		    int	how;
2637 		    int vflags;
2638 
2639 		    if (v->name[0] == 0)
2640 			goto bad_modifier;
2641 
2642 		    v_ctxt = ctxt;
2643 		    sv_name = NULL;
2644 		    ++tstr;
2645 		    if (v->flags & VAR_JUNK) {
2646 			/*
2647 			 * We need to bmake_strdup() it incase
2648 			 * VarGetPattern() recurses.
2649 			 */
2650 			sv_name = v->name;
2651 			v->name = bmake_strdup(v->name);
2652 		    } else if (ctxt != VAR_GLOBAL) {
2653 			Var *gv = VarFind(v->name, ctxt, 0);
2654 			if (gv == NULL)
2655 			    v_ctxt = VAR_GLOBAL;
2656 			else
2657 			    VarFreeEnv(gv, TRUE);
2658 		    }
2659 
2660 		    switch ((how = *tstr)) {
2661 		    case '+':
2662 		    case '?':
2663 		    case '!':
2664 			cp = &tstr[2];
2665 			break;
2666 		    default:
2667 			cp = ++tstr;
2668 			break;
2669 		    }
2670 		    delim = startc == PROPEN ? PRCLOSE : BRCLOSE;
2671 		    pattern.flags = 0;
2672 
2673 		    vflags = (flags & VARF_WANTRES) ? 0 : VAR_NOSUBST;
2674 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, flags,
2675 						&cp, delim, &vflags,
2676 						&pattern.rightLen,
2677 						NULL);
2678 		    if (v->flags & VAR_JUNK) {
2679 			/* restore original name */
2680 			free(v->name);
2681 			v->name = sv_name;
2682 		    }
2683 		    if (pattern.rhs == NULL)
2684 			goto cleanup;
2685 
2686 		    termc = *--cp;
2687 		    delim = '\0';
2688 
2689 		    if (flags & VARF_WANTRES) {
2690 			switch (how) {
2691 			case '+':
2692 			    Var_Append(v->name, pattern.rhs, v_ctxt);
2693 			    break;
2694 			case '!':
2695 			    newStr = Cmd_Exec(pattern.rhs, &emsg);
2696 			    if (emsg)
2697 				Error(emsg, nstr);
2698 			    else
2699 				Var_Set(v->name, newStr,  v_ctxt, 0);
2700 			    free(newStr);
2701 			    break;
2702 			case '?':
2703 			    if ((v->flags & VAR_JUNK) == 0)
2704 				break;
2705 			    /* FALLTHROUGH */
2706 			default:
2707 			    Var_Set(v->name, pattern.rhs, v_ctxt, 0);
2708 			    break;
2709 			}
2710 		    }
2711 		    free(UNCONST(pattern.rhs));
2712 		    newStr = varNoError;
2713 		    break;
2714 		}
2715 		goto default_case; /* "::<unrecognised>" */
2716 	    }
2717 	case '@':
2718 	    {
2719 		VarLoop_t	loop;
2720 		int vflags = VAR_NOSUBST;
2721 
2722 		cp = ++tstr;
2723 		delim = '@';
2724 		if ((loop.tvar = VarGetPattern(ctxt, &parsestate, flags,
2725 					       &cp, delim,
2726 					       &vflags, &loop.tvarLen,
2727 					       NULL)) == NULL)
2728 		    goto cleanup;
2729 
2730 		if ((loop.str = VarGetPattern(ctxt, &parsestate, flags,
2731 					      &cp, delim,
2732 					      &vflags, &loop.strLen,
2733 					      NULL)) == NULL)
2734 		    goto cleanup;
2735 
2736 		termc = *cp;
2737 		delim = '\0';
2738 
2739 		loop.errnum = flags & VARF_UNDEFERR;
2740 		loop.ctxt = ctxt;
2741 		newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
2742 				   &loop);
2743 		Var_Delete(loop.tvar, ctxt);
2744 		free(loop.tvar);
2745 		free(loop.str);
2746 		break;
2747 	    }
2748 	case '_':			/* remember current value */
2749 	    cp = tstr + 1;	/* make sure it is set */
2750 	    if (STRMOD_MATCHX(tstr, "_", 1)) {
2751 		if (tstr[1] == '=') {
2752 		    char *np;
2753 		    int n;
2754 
2755 		    cp++;
2756 		    n = strcspn(cp, ":)}");
2757 		    np = bmake_strndup(cp, n+1);
2758 		    np[n] = '\0';
2759 		    cp = tstr + 2 + n;
2760 		    Var_Set(np, nstr, ctxt, 0);
2761 		    free(np);
2762 		} else {
2763 		    Var_Set("_", nstr, ctxt, 0);
2764 		}
2765 		newStr = nstr;
2766 		termc = *cp;
2767 		break;
2768 	    }
2769 	    goto default_case;
2770 	case 'D':
2771 	case 'U':
2772 	    {
2773 		Buffer  buf;    	/* Buffer for patterns */
2774 		int	nflags;
2775 
2776 		if (flags & VARF_WANTRES) {
2777 		    int wantres;
2778 		    if (*tstr == 'U')
2779 			wantres = ((v->flags & VAR_JUNK) != 0);
2780 		    else
2781 			wantres = ((v->flags & VAR_JUNK) == 0);
2782 		    nflags = flags & ~VARF_WANTRES;
2783 		    if (wantres)
2784 			nflags |= VARF_WANTRES;
2785 		} else
2786 		    nflags = flags;
2787 		/*
2788 		 * Pass through tstr looking for 1) escaped delimiters,
2789 		 * '$'s and backslashes (place the escaped character in
2790 		 * uninterpreted) and 2) unescaped $'s that aren't before
2791 		 * the delimiter (expand the variable substitution).
2792 		 * The result is left in the Buffer buf.
2793 		 */
2794 		Buf_Init(&buf, 0);
2795 		for (cp = tstr + 1;
2796 		     *cp != endc && *cp != ':' && *cp != '\0';
2797 		     cp++) {
2798 		    if ((*cp == '\\') &&
2799 			((cp[1] == ':') ||
2800 			 (cp[1] == '$') ||
2801 			 (cp[1] == endc) ||
2802 			 (cp[1] == '\\')))
2803 			{
2804 			    Buf_AddByte(&buf, cp[1]);
2805 			    cp++;
2806 			} else if (*cp == '$') {
2807 			    /*
2808 			     * If unescaped dollar sign, assume it's a
2809 			     * variable substitution and recurse.
2810 			     */
2811 			    char    *cp2;
2812 			    int	    len;
2813 			    void    *freeIt;
2814 
2815 			    cp2 = Var_Parse(cp, ctxt, nflags, &len, &freeIt);
2816 			    Buf_AddBytes(&buf, strlen(cp2), cp2);
2817 			    free(freeIt);
2818 			    cp += len - 1;
2819 			} else {
2820 			    Buf_AddByte(&buf, *cp);
2821 			}
2822 		}
2823 
2824 		termc = *cp;
2825 
2826 		if ((v->flags & VAR_JUNK) != 0)
2827 		    v->flags |= VAR_KEEP;
2828 		if (nflags & VARF_WANTRES) {
2829 		    newStr = Buf_Destroy(&buf, FALSE);
2830 		} else {
2831 		    newStr = nstr;
2832 		    Buf_Destroy(&buf, TRUE);
2833 		}
2834 		break;
2835 	    }
2836 	case 'L':
2837 	    {
2838 		if ((v->flags & VAR_JUNK) != 0)
2839 		    v->flags |= VAR_KEEP;
2840 		newStr = bmake_strdup(v->name);
2841 		cp = ++tstr;
2842 		termc = *tstr;
2843 		break;
2844 	    }
2845 	case 'P':
2846 	    {
2847 		GNode *gn;
2848 
2849 		if ((v->flags & VAR_JUNK) != 0)
2850 		    v->flags |= VAR_KEEP;
2851 		gn = Targ_FindNode(v->name, TARG_NOCREATE);
2852 		if (gn == NULL || gn->type & OP_NOPATH) {
2853 		    newStr = NULL;
2854 		} else if (gn->path) {
2855 		    newStr = bmake_strdup(gn->path);
2856 		} else {
2857 		    newStr = Dir_FindFile(v->name, Suff_FindPath(gn));
2858 		}
2859 		if (!newStr) {
2860 		    newStr = bmake_strdup(v->name);
2861 		}
2862 		cp = ++tstr;
2863 		termc = *tstr;
2864 		break;
2865 	    }
2866 	case '!':
2867 	    {
2868 		const char *emsg;
2869 		VarPattern 	    pattern;
2870 		pattern.flags = 0;
2871 
2872 		delim = '!';
2873 		emsg = NULL;
2874 		cp = ++tstr;
2875 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, flags,
2876 						 &cp, delim,
2877 						 NULL, &pattern.rightLen,
2878 						 NULL)) == NULL)
2879 		    goto cleanup;
2880 		if (flags & VARF_WANTRES)
2881 		    newStr = Cmd_Exec(pattern.rhs, &emsg);
2882 		else
2883 		    newStr = varNoError;
2884 		free(UNCONST(pattern.rhs));
2885 		if (emsg)
2886 		    Error(emsg, nstr);
2887 		termc = *cp;
2888 		delim = '\0';
2889 		if (v->flags & VAR_JUNK) {
2890 		    v->flags |= VAR_KEEP;
2891 		}
2892 		break;
2893 	    }
2894 	case '[':
2895 	    {
2896 		/*
2897 		 * Look for the closing ']', recursively
2898 		 * expanding any embedded variables.
2899 		 *
2900 		 * estr is a pointer to the expanded result,
2901 		 * which we must free().
2902 		 */
2903 		char *estr;
2904 
2905 		cp = tstr+1; /* point to char after '[' */
2906 		delim = ']'; /* look for closing ']' */
2907 		estr = VarGetPattern(ctxt, &parsestate,
2908 				     flags, &cp, delim,
2909 				     NULL, NULL, NULL);
2910 		if (estr == NULL)
2911 		    goto cleanup; /* report missing ']' */
2912 		/* now cp points just after the closing ']' */
2913 		delim = '\0';
2914 		if (cp[0] != ':' && cp[0] != endc) {
2915 		    /* Found junk after ']' */
2916 		    free(estr);
2917 		    goto bad_modifier;
2918 		}
2919 		if (estr[0] == '\0') {
2920 		    /* Found empty square brackets in ":[]". */
2921 		    free(estr);
2922 		    goto bad_modifier;
2923 		} else if (estr[0] == '#' && estr[1] == '\0') {
2924 		    /* Found ":[#]" */
2925 
2926 		    /*
2927 		     * We will need enough space for the decimal
2928 		     * representation of an int.  We calculate the
2929 		     * space needed for the octal representation,
2930 		     * and add enough slop to cope with a '-' sign
2931 		     * (which should never be needed) and a '\0'
2932 		     * string terminator.
2933 		     */
2934 		    int newStrSize =
2935 			(sizeof(int) * CHAR_BIT + 2) / 3 + 2;
2936 
2937 		    newStr = bmake_malloc(newStrSize);
2938 		    if (parsestate.oneBigWord) {
2939 			strncpy(newStr, "1", newStrSize);
2940 		    } else {
2941 			/* XXX: brk_string() is a rather expensive
2942 			 * way of counting words. */
2943 			char **av;
2944 			char *as;
2945 			int ac;
2946 
2947 			av = brk_string(nstr, &ac, FALSE, &as);
2948 			snprintf(newStr, newStrSize,  "%d", ac);
2949 			free(as);
2950 			free(av);
2951 		    }
2952 		    termc = *cp;
2953 		    free(estr);
2954 		    break;
2955 		} else if (estr[0] == '*' && estr[1] == '\0') {
2956 		    /* Found ":[*]" */
2957 		    parsestate.oneBigWord = TRUE;
2958 		    newStr = nstr;
2959 		    termc = *cp;
2960 		    free(estr);
2961 		    break;
2962 		} else if (estr[0] == '@' && estr[1] == '\0') {
2963 		    /* Found ":[@]" */
2964 		    parsestate.oneBigWord = FALSE;
2965 		    newStr = nstr;
2966 		    termc = *cp;
2967 		    free(estr);
2968 		    break;
2969 		} else {
2970 		    /*
2971 		     * We expect estr to contain a single
2972 		     * integer for :[N], or two integers
2973 		     * separated by ".." for :[start..end].
2974 		     */
2975 		    VarSelectWords_t seldata = { 0, 0 };
2976 
2977 		    seldata.start = strtol(estr, &ep, 0);
2978 		    if (ep == estr) {
2979 			/* Found junk instead of a number */
2980 			free(estr);
2981 			goto bad_modifier;
2982 		    } else if (ep[0] == '\0') {
2983 			/* Found only one integer in :[N] */
2984 			seldata.end = seldata.start;
2985 		    } else if (ep[0] == '.' && ep[1] == '.' &&
2986 			       ep[2] != '\0') {
2987 			/* Expecting another integer after ".." */
2988 			ep += 2;
2989 			seldata.end = strtol(ep, &ep, 0);
2990 			if (ep[0] != '\0') {
2991 			    /* Found junk after ".." */
2992 			    free(estr);
2993 			    goto bad_modifier;
2994 			}
2995 		    } else {
2996 			/* Found junk instead of ".." */
2997 			free(estr);
2998 			goto bad_modifier;
2999 		    }
3000 		    /*
3001 		     * Now seldata is properly filled in,
3002 		     * but we still have to check for 0 as
3003 		     * a special case.
3004 		     */
3005 		    if (seldata.start == 0 && seldata.end == 0) {
3006 			/* ":[0]" or perhaps ":[0..0]" */
3007 			parsestate.oneBigWord = TRUE;
3008 			newStr = nstr;
3009 			termc = *cp;
3010 			free(estr);
3011 			break;
3012 		    } else if (seldata.start == 0 ||
3013 			       seldata.end == 0) {
3014 			/* ":[0..N]" or ":[N..0]" */
3015 			free(estr);
3016 			goto bad_modifier;
3017 		    }
3018 		    /*
3019 		     * Normal case: select the words
3020 		     * described by seldata.
3021 		     */
3022 		    newStr = VarSelectWords(ctxt, &parsestate,
3023 					    nstr, &seldata);
3024 
3025 		    termc = *cp;
3026 		    free(estr);
3027 		    break;
3028 		}
3029 
3030 	    }
3031 	case 'g':
3032 	    cp = tstr + 1;	/* make sure it is set */
3033 	    if (STRMOD_MATCHX(tstr, "gmtime", 6)) {
3034 		if (tstr[6] == '=') {
3035 		    utc = strtoul(&tstr[7], &ep, 10);
3036 		    cp = ep;
3037 		} else {
3038 		    utc = 0;
3039 		    cp = tstr + 6;
3040 		}
3041 		newStr = VarStrftime(nstr, 1, utc);
3042 		termc = *cp;
3043 	    } else {
3044 		goto default_case;
3045 	    }
3046 	    break;
3047 	case 'h':
3048 	    cp = tstr + 1;	/* make sure it is set */
3049 	    if (STRMOD_MATCH(tstr, "hash", 4)) {
3050 		newStr = VarHash(nstr);
3051 		cp = tstr + 4;
3052 		termc = *cp;
3053 	    } else {
3054 		goto default_case;
3055 	    }
3056 	    break;
3057 	case 'l':
3058 	    cp = tstr + 1;	/* make sure it is set */
3059 	    if (STRMOD_MATCHX(tstr, "localtime", 9)) {
3060 		if (tstr[9] == '=') {
3061 		    utc = strtoul(&tstr[10], &ep, 10);
3062 		    cp = ep;
3063 		} else {
3064 		    utc = 0;
3065 		    cp = tstr + 9;
3066 		}
3067 		newStr = VarStrftime(nstr, 0, utc);
3068 		termc = *cp;
3069 	    } else {
3070 		goto default_case;
3071 	    }
3072 	    break;
3073 	case 't':
3074 	    {
3075 		cp = tstr + 1;	/* make sure it is set */
3076 		if (tstr[1] != endc && tstr[1] != ':') {
3077 		    if (tstr[1] == 's') {
3078 			/*
3079 			 * Use the char (if any) at tstr[2]
3080 			 * as the word separator.
3081 			 */
3082 			VarPattern pattern;
3083 
3084 			if (tstr[2] != endc &&
3085 			    (tstr[3] == endc || tstr[3] == ':')) {
3086 			    /* ":ts<unrecognised><endc>" or
3087 			     * ":ts<unrecognised>:" */
3088 			    parsestate.varSpace = tstr[2];
3089 			    cp = tstr + 3;
3090 			} else if (tstr[2] == endc || tstr[2] == ':') {
3091 			    /* ":ts<endc>" or ":ts:" */
3092 			    parsestate.varSpace = 0; /* no separator */
3093 			    cp = tstr + 2;
3094 			} else if (tstr[2] == '\\') {
3095 			    const char *xp = &tstr[3];
3096 			    int base = 8; /* assume octal */
3097 
3098 			    switch (tstr[3]) {
3099 			    case 'n':
3100 				parsestate.varSpace = '\n';
3101 				cp = tstr + 4;
3102 				break;
3103 			    case 't':
3104 				parsestate.varSpace = '\t';
3105 				cp = tstr + 4;
3106 				break;
3107 			    case 'x':
3108 				base = 16;
3109 				xp++;
3110 				goto get_numeric;
3111 			    case '0':
3112 				base = 0;
3113 				goto get_numeric;
3114 			    default:
3115 				if (isdigit((unsigned char)tstr[3])) {
3116 
3117 				get_numeric:
3118 				    parsestate.varSpace =
3119 					strtoul(xp, &ep, base);
3120 				    if (*ep != ':' && *ep != endc)
3121 					goto bad_modifier;
3122 				    cp = ep;
3123 				} else {
3124 				    /*
3125 				     * ":ts<backslash><unrecognised>".
3126 				     */
3127 				    goto bad_modifier;
3128 				}
3129 				break;
3130 			    }
3131 			} else {
3132 			    /*
3133 			     * Found ":ts<unrecognised><unrecognised>".
3134 			     */
3135 			    goto bad_modifier;
3136 			}
3137 
3138 			termc = *cp;
3139 
3140 			/*
3141 			 * We cannot be certain that VarModify
3142 			 * will be used - even if there is a
3143 			 * subsequent modifier, so do a no-op
3144 			 * VarSubstitute now to for str to be
3145 			 * re-expanded without the spaces.
3146 			 */
3147 			pattern.flags = VAR_SUB_ONE;
3148 			pattern.lhs = pattern.rhs = "\032";
3149 			pattern.leftLen = pattern.rightLen = 1;
3150 
3151 			newStr = VarModify(ctxt, &parsestate, nstr,
3152 					   VarSubstitute,
3153 					   &pattern);
3154 		    } else if (tstr[2] == endc || tstr[2] == ':') {
3155 			/*
3156 			 * Check for two-character options:
3157 			 * ":tu", ":tl"
3158 			 */
3159 			if (tstr[1] == 'A') { /* absolute path */
3160 			    newStr = VarModify(ctxt, &parsestate, nstr,
3161 					       VarRealpath, NULL);
3162 			    cp = tstr + 2;
3163 			    termc = *cp;
3164 			} else if (tstr[1] == 'u') {
3165 			    char *dp = bmake_strdup(nstr);
3166 			    for (newStr = dp; *dp; dp++)
3167 				*dp = toupper((unsigned char)*dp);
3168 			    cp = tstr + 2;
3169 			    termc = *cp;
3170 			} else if (tstr[1] == 'l') {
3171 			    char *dp = bmake_strdup(nstr);
3172 			    for (newStr = dp; *dp; dp++)
3173 				*dp = tolower((unsigned char)*dp);
3174 			    cp = tstr + 2;
3175 			    termc = *cp;
3176 			} else if (tstr[1] == 'W' || tstr[1] == 'w') {
3177 			    parsestate.oneBigWord = (tstr[1] == 'W');
3178 			    newStr = nstr;
3179 			    cp = tstr + 2;
3180 			    termc = *cp;
3181 			} else {
3182 			    /* Found ":t<unrecognised>:" or
3183 			     * ":t<unrecognised><endc>". */
3184 			    goto bad_modifier;
3185 			}
3186 		    } else {
3187 			/*
3188 			 * Found ":t<unrecognised><unrecognised>".
3189 			 */
3190 			goto bad_modifier;
3191 		    }
3192 		} else {
3193 		    /*
3194 		     * Found ":t<endc>" or ":t:".
3195 		     */
3196 		    goto bad_modifier;
3197 		}
3198 		break;
3199 	    }
3200 	case 'N':
3201 	case 'M':
3202 	    {
3203 		char    *pattern;
3204 		const char *endpat; /* points just after end of pattern */
3205 		char    *cp2;
3206 		Boolean copy;	/* pattern should be, or has been, copied */
3207 		Boolean needSubst;
3208 		int nest;
3209 
3210 		copy = FALSE;
3211 		needSubst = FALSE;
3212 		nest = 1;
3213 		/*
3214 		 * In the loop below, ignore ':' unless we are at
3215 		 * (or back to) the original brace level.
3216 		 * XXX This will likely not work right if $() and ${}
3217 		 * are intermixed.
3218 		 */
3219 		for (cp = tstr + 1;
3220 		     *cp != '\0' && !(*cp == ':' && nest == 1);
3221 		     cp++)
3222 		    {
3223 			if (*cp == '\\' &&
3224 			    (cp[1] == ':' ||
3225 			     cp[1] == endc || cp[1] == startc)) {
3226 			    if (!needSubst) {
3227 				copy = TRUE;
3228 			    }
3229 			    cp++;
3230 			    continue;
3231 			}
3232 			if (*cp == '$') {
3233 			    needSubst = TRUE;
3234 			}
3235 			if (*cp == '(' || *cp == '{')
3236 			    ++nest;
3237 			if (*cp == ')' || *cp == '}') {
3238 			    --nest;
3239 			    if (nest == 0)
3240 				break;
3241 			}
3242 		    }
3243 		termc = *cp;
3244 		endpat = cp;
3245 		if (copy) {
3246 		    /*
3247 		     * Need to compress the \:'s out of the pattern, so
3248 		     * allocate enough room to hold the uncompressed
3249 		     * pattern (note that cp started at tstr+1, so
3250 		     * cp - tstr takes the null byte into account) and
3251 		     * compress the pattern into the space.
3252 		     */
3253 		    pattern = bmake_malloc(cp - tstr);
3254 		    for (cp2 = pattern, cp = tstr + 1;
3255 			 cp < endpat;
3256 			 cp++, cp2++)
3257 			{
3258 			    if ((*cp == '\\') && (cp+1 < endpat) &&
3259 				(cp[1] == ':' || cp[1] == endc)) {
3260 				cp++;
3261 			    }
3262 			    *cp2 = *cp;
3263 			}
3264 		    *cp2 = '\0';
3265 		    endpat = cp2;
3266 		} else {
3267 		    /*
3268 		     * Either Var_Subst or VarModify will need a
3269 		     * nul-terminated string soon, so construct one now.
3270 		     */
3271 		    pattern = bmake_strndup(tstr+1, endpat - (tstr + 1));
3272 		}
3273 		if (needSubst) {
3274 		    /*
3275 		     * pattern contains embedded '$', so use Var_Subst to
3276 		     * expand it.
3277 		     */
3278 		    cp2 = pattern;
3279 		    pattern = Var_Subst(NULL, cp2, ctxt, flags | VARF_WANTRES);
3280 		    free(cp2);
3281 		}
3282 		if (DEBUG(VAR))
3283 		    fprintf(debug_file, "Pattern[%s] for [%s] is [%s]\n",
3284 			v->name, nstr, pattern);
3285 		if (*tstr == 'M') {
3286 		    newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
3287 				       pattern);
3288 		} else {
3289 		    newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
3290 				       pattern);
3291 		}
3292 		free(pattern);
3293 		break;
3294 	    }
3295 	case 'S':
3296 	    {
3297 		VarPattern 	    pattern;
3298 		Var_Parse_State tmpparsestate;
3299 
3300 		pattern.flags = 0;
3301 		tmpparsestate = parsestate;
3302 		delim = tstr[1];
3303 		tstr += 2;
3304 
3305 		/*
3306 		 * If pattern begins with '^', it is anchored to the
3307 		 * start of the word -- skip over it and flag pattern.
3308 		 */
3309 		if (*tstr == '^') {
3310 		    pattern.flags |= VAR_MATCH_START;
3311 		    tstr += 1;
3312 		}
3313 
3314 		cp = tstr;
3315 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, flags,
3316 						 &cp, delim,
3317 						 &pattern.flags,
3318 						 &pattern.leftLen,
3319 						 NULL)) == NULL)
3320 		    goto cleanup;
3321 
3322 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, flags,
3323 						 &cp, delim, NULL,
3324 						 &pattern.rightLen,
3325 						 &pattern)) == NULL)
3326 		    goto cleanup;
3327 
3328 		/*
3329 		 * Check for global substitution. If 'g' after the final
3330 		 * delimiter, substitution is global and is marked that
3331 		 * way.
3332 		 */
3333 		for (;; cp++) {
3334 		    switch (*cp) {
3335 		    case 'g':
3336 			pattern.flags |= VAR_SUB_GLOBAL;
3337 			continue;
3338 		    case '1':
3339 			pattern.flags |= VAR_SUB_ONE;
3340 			continue;
3341 		    case 'W':
3342 			tmpparsestate.oneBigWord = TRUE;
3343 			continue;
3344 		    }
3345 		    break;
3346 		}
3347 
3348 		termc = *cp;
3349 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
3350 				   VarSubstitute,
3351 				   &pattern);
3352 
3353 		/*
3354 		 * Free the two strings.
3355 		 */
3356 		free(UNCONST(pattern.lhs));
3357 		free(UNCONST(pattern.rhs));
3358 		delim = '\0';
3359 		break;
3360 	    }
3361 	case '?':
3362 	    {
3363 		VarPattern 	pattern;
3364 		Boolean	value;
3365 		int cond_rc;
3366 		int lhs_flags, rhs_flags;
3367 
3368 		/* find ':', and then substitute accordingly */
3369 		if (flags & VARF_WANTRES) {
3370 		    cond_rc = Cond_EvalExpression(NULL, v->name, &value, 0, FALSE);
3371 		    if (cond_rc == COND_INVALID) {
3372 			lhs_flags = rhs_flags = VAR_NOSUBST;
3373 		    } else if (value) {
3374 			lhs_flags = 0;
3375 			rhs_flags = VAR_NOSUBST;
3376 		    } else {
3377 			lhs_flags = VAR_NOSUBST;
3378 			rhs_flags = 0;
3379 		    }
3380 		} else {
3381 		    /* we are just consuming and discarding */
3382 		    cond_rc = value = 0;
3383 		    lhs_flags = rhs_flags = VAR_NOSUBST;
3384 		}
3385 		pattern.flags = 0;
3386 
3387 		cp = ++tstr;
3388 		delim = ':';
3389 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, flags,
3390 						 &cp, delim, &lhs_flags,
3391 						 &pattern.leftLen,
3392 						 NULL)) == NULL)
3393 		    goto cleanup;
3394 
3395 		/* BROPEN or PROPEN */
3396 		delim = endc;
3397 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, flags,
3398 						 &cp, delim, &rhs_flags,
3399 						 &pattern.rightLen,
3400 						 NULL)) == NULL)
3401 		    goto cleanup;
3402 
3403 		termc = *--cp;
3404 		delim = '\0';
3405 		if (cond_rc == COND_INVALID) {
3406 		    Error("Bad conditional expression `%s' in %s?%s:%s",
3407 			  v->name, v->name, pattern.lhs, pattern.rhs);
3408 		    goto cleanup;
3409 		}
3410 
3411 		if (value) {
3412 		    newStr = UNCONST(pattern.lhs);
3413 		    free(UNCONST(pattern.rhs));
3414 		} else {
3415 		    newStr = UNCONST(pattern.rhs);
3416 		    free(UNCONST(pattern.lhs));
3417 		}
3418 		if (v->flags & VAR_JUNK) {
3419 		    v->flags |= VAR_KEEP;
3420 		}
3421 		break;
3422 	    }
3423 #ifndef NO_REGEX
3424 	case 'C':
3425 	    {
3426 		VarREPattern    pattern;
3427 		char           *re;
3428 		int             error;
3429 		Var_Parse_State tmpparsestate;
3430 
3431 		pattern.flags = 0;
3432 		tmpparsestate = parsestate;
3433 		delim = tstr[1];
3434 		tstr += 2;
3435 
3436 		cp = tstr;
3437 
3438 		if ((re = VarGetPattern(ctxt, &parsestate, flags, &cp, delim,
3439 					NULL, NULL, NULL)) == NULL)
3440 		    goto cleanup;
3441 
3442 		if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
3443 						     flags, &cp, delim, NULL,
3444 						     NULL, NULL)) == NULL){
3445 		    free(re);
3446 		    goto cleanup;
3447 		}
3448 
3449 		for (;; cp++) {
3450 		    switch (*cp) {
3451 		    case 'g':
3452 			pattern.flags |= VAR_SUB_GLOBAL;
3453 			continue;
3454 		    case '1':
3455 			pattern.flags |= VAR_SUB_ONE;
3456 			continue;
3457 		    case 'W':
3458 			tmpparsestate.oneBigWord = TRUE;
3459 			continue;
3460 		    }
3461 		    break;
3462 		}
3463 
3464 		termc = *cp;
3465 
3466 		error = regcomp(&pattern.re, re, REG_EXTENDED);
3467 		free(re);
3468 		if (error)  {
3469 		    *lengthPtr = cp - start + 1;
3470 		    VarREError(error, &pattern.re, "RE substitution error");
3471 		    free(pattern.replace);
3472 		    goto cleanup;
3473 		}
3474 
3475 		pattern.nsub = pattern.re.re_nsub + 1;
3476 		if (pattern.nsub < 1)
3477 		    pattern.nsub = 1;
3478 		if (pattern.nsub > 10)
3479 		    pattern.nsub = 10;
3480 		pattern.matches = bmake_malloc(pattern.nsub *
3481 					  sizeof(regmatch_t));
3482 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
3483 				   VarRESubstitute,
3484 				   &pattern);
3485 		regfree(&pattern.re);
3486 		free(pattern.replace);
3487 		free(pattern.matches);
3488 		delim = '\0';
3489 		break;
3490 	    }
3491 #endif
3492 	case 'q':
3493 	case 'Q':
3494 	    if (tstr[1] == endc || tstr[1] == ':') {
3495 		newStr = VarQuote(nstr, modifier == 'q');
3496 		cp = tstr + 1;
3497 		termc = *cp;
3498 		break;
3499 	    }
3500 	    goto default_case;
3501 	case 'T':
3502 	    if (tstr[1] == endc || tstr[1] == ':') {
3503 		newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
3504 				   NULL);
3505 		cp = tstr + 1;
3506 		termc = *cp;
3507 		break;
3508 	    }
3509 	    goto default_case;
3510 	case 'H':
3511 	    if (tstr[1] == endc || tstr[1] == ':') {
3512 		newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
3513 				   NULL);
3514 		cp = tstr + 1;
3515 		termc = *cp;
3516 		break;
3517 	    }
3518 	    goto default_case;
3519 	case 'E':
3520 	    if (tstr[1] == endc || tstr[1] == ':') {
3521 		newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
3522 				   NULL);
3523 		cp = tstr + 1;
3524 		termc = *cp;
3525 		break;
3526 	    }
3527 	    goto default_case;
3528 	case 'R':
3529 	    if (tstr[1] == endc || tstr[1] == ':') {
3530 		newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
3531 				   NULL);
3532 		cp = tstr + 1;
3533 		termc = *cp;
3534 		break;
3535 	    }
3536 	    goto default_case;
3537 	case 'r':
3538 	    cp = tstr + 1;	/* make sure it is set */
3539 	    if (STRMOD_MATCHX(tstr, "range", 5)) {
3540 		int n;
3541 
3542 		if (tstr[5] == '=') {
3543 		    n = strtoul(&tstr[6], &ep, 10);
3544 		    cp = ep;
3545 		} else {
3546 		    n = 0;
3547 		    cp = tstr + 5;
3548 		}
3549 		newStr = VarRange(nstr, n);
3550 		termc = *cp;
3551 		break;
3552 	    }
3553 	    goto default_case;
3554 	case 'O':
3555 	    {
3556 		char otype;
3557 
3558 		cp = tstr + 1;	/* skip to the rest in any case */
3559 		if (tstr[1] == endc || tstr[1] == ':') {
3560 		    otype = 's';
3561 		    termc = *cp;
3562 		} else if ( (tstr[1] == 'x') &&
3563 			    (tstr[2] == endc || tstr[2] == ':') ) {
3564 		    otype = tstr[1];
3565 		    cp = tstr + 2;
3566 		    termc = *cp;
3567 		} else {
3568 		    goto bad_modifier;
3569 		}
3570 		newStr = VarOrder(nstr, otype);
3571 		break;
3572 	    }
3573 	case 'u':
3574 	    if (tstr[1] == endc || tstr[1] == ':') {
3575 		newStr = VarUniq(nstr);
3576 		cp = tstr + 1;
3577 		termc = *cp;
3578 		break;
3579 	    }
3580 	    goto default_case;
3581 #ifdef SUNSHCMD
3582 	case 's':
3583 	    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
3584 		const char *emsg;
3585 		if (flags & VARF_WANTRES) {
3586 		    newStr = Cmd_Exec(nstr, &emsg);
3587 		    if (emsg)
3588 			Error(emsg, nstr);
3589 		} else
3590 		    newStr = varNoError;
3591 		cp = tstr + 2;
3592 		termc = *cp;
3593 		break;
3594 	    }
3595 	    goto default_case;
3596 #endif
3597 	default:
3598 	default_case:
3599 	{
3600 #ifdef SYSVVARSUB
3601 	    /*
3602 	     * This can either be a bogus modifier or a System-V
3603 	     * substitution command.
3604 	     */
3605 	    VarPattern      pattern;
3606 	    Boolean         eqFound;
3607 
3608 	    pattern.flags = 0;
3609 	    eqFound = FALSE;
3610 	    /*
3611 	     * First we make a pass through the string trying
3612 	     * to verify it is a SYSV-make-style translation:
3613 	     * it must be: <string1>=<string2>)
3614 	     */
3615 	    cp = tstr;
3616 	    cnt = 1;
3617 	    while (*cp != '\0' && cnt) {
3618 		if (*cp == '=') {
3619 		    eqFound = TRUE;
3620 		    /* continue looking for endc */
3621 		}
3622 		else if (*cp == endc)
3623 		    cnt--;
3624 		else if (*cp == startc)
3625 		    cnt++;
3626 		if (cnt)
3627 		    cp++;
3628 	    }
3629 	    if (*cp == endc && eqFound) {
3630 
3631 		/*
3632 		 * Now we break this sucker into the lhs and
3633 		 * rhs. We must null terminate them of course.
3634 		 */
3635 		delim='=';
3636 		cp = tstr;
3637 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
3638 						 flags, &cp, delim, &pattern.flags,
3639 						 &pattern.leftLen, NULL)) == NULL)
3640 		    goto cleanup;
3641 		delim = endc;
3642 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
3643 						 flags, &cp, delim, NULL, &pattern.rightLen,
3644 						 &pattern)) == NULL)
3645 		    goto cleanup;
3646 
3647 		/*
3648 		 * SYSV modifications happen through the whole
3649 		 * string. Note the pattern is anchored at the end.
3650 		 */
3651 		termc = *--cp;
3652 		delim = '\0';
3653 		if (pattern.leftLen == 0 && *nstr == '\0') {
3654 		    newStr = nstr;	/* special case */
3655 		} else {
3656 		    newStr = VarModify(ctxt, &parsestate, nstr,
3657 				       VarSYSVMatch,
3658 				       &pattern);
3659 		}
3660 		free(UNCONST(pattern.lhs));
3661 		free(UNCONST(pattern.rhs));
3662 	    } else
3663 #endif
3664 		{
3665 		    Error("Unknown modifier '%c'", *tstr);
3666 		    for (cp = tstr+1;
3667 			 *cp != ':' && *cp != endc && *cp != '\0';
3668 			 cp++)
3669 			continue;
3670 		    termc = *cp;
3671 		    newStr = var_Error;
3672 		}
3673 	    }
3674 	}
3675 	if (DEBUG(VAR)) {
3676 	    fprintf(debug_file, "Result[%s] of :%c is \"%s\"\n",
3677 		v->name, modifier, newStr);
3678 	}
3679 
3680 	if (newStr != nstr) {
3681 	    if (*freePtr) {
3682 		free(nstr);
3683 		*freePtr = NULL;
3684 	    }
3685 	    nstr = newStr;
3686 	    if (nstr != var_Error && nstr != varNoError) {
3687 		*freePtr = nstr;
3688 	    }
3689 	}
3690 	if (termc == '\0' && endc != '\0') {
3691 	    Error("Unclosed variable specification (expecting '%c') for \"%s\" (value \"%s\") modifier %c", endc, v->name, nstr, modifier);
3692 	} else if (termc == ':') {
3693 	    cp++;
3694 	}
3695 	tstr = cp;
3696     }
3697  out:
3698     *lengthPtr = tstr - start;
3699     return (nstr);
3700 
3701  bad_modifier:
3702     /* "{(" */
3703     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
3704 	  v->name);
3705 
3706  cleanup:
3707     *lengthPtr = cp - start;
3708     if (delim != '\0')
3709 	Error("Unclosed substitution for %s (%c missing)",
3710 	      v->name, delim);
3711     free(*freePtr);
3712     *freePtr = NULL;
3713     return (var_Error);
3714 }
3715 
3716 /*-
3717  *-----------------------------------------------------------------------
3718  * Var_Parse --
3719  *	Given the start of a variable invocation, extract the variable
3720  *	name and find its value, then modify it according to the
3721  *	specification.
3722  *
3723  * Input:
3724  *	str		The string to parse
3725  *	ctxt		The context for the variable
3726  *	flags		VARF_UNDEFERR	if undefineds are an error
3727  *			VARF_WANTRES	if we actually want the result
3728  *			VARF_ASSIGN	if we are in a := assignment
3729  *	lengthPtr	OUT: The length of the specification
3730  *	freePtr		OUT: Non-NULL if caller should free *freePtr
3731  *
3732  * Results:
3733  *	The (possibly-modified) value of the variable or var_Error if the
3734  *	specification is invalid. The length of the specification is
3735  *	placed in *lengthPtr (for invalid specifications, this is just
3736  *	2...?).
3737  *	If *freePtr is non-NULL then it's a pointer that the caller
3738  *	should pass to free() to free memory used by the result.
3739  *
3740  * Side Effects:
3741  *	None.
3742  *
3743  *-----------------------------------------------------------------------
3744  */
3745 /* coverity[+alloc : arg-*4] */
3746 char *
3747 Var_Parse(const char *str, GNode *ctxt, int flags,
3748 	  int *lengthPtr, void **freePtr)
3749 {
3750     const char	   *tstr;    	/* Pointer into str */
3751     Var		   *v;		/* Variable in invocation */
3752     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
3753     char	    endc;    	/* Ending character when variable in parens
3754 				 * or braces */
3755     char	    startc;	/* Starting character when variable in parens
3756 				 * or braces */
3757     int		    vlen;	/* Length of variable name */
3758     const char 	   *start;	/* Points to original start of str */
3759     char	   *nstr;	/* New string, used during expansion */
3760     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
3761 				 * expanding it in a non-local context. This
3762 				 * is done to support dynamic sources. The
3763 				 * result is just the invocation, unaltered */
3764     const char     *extramodifiers; /* extra modifiers to apply first */
3765     char	  name[2];
3766 
3767     *freePtr = NULL;
3768     extramodifiers = NULL;
3769     dynamic = FALSE;
3770     start = str;
3771 
3772     startc = str[1];
3773     if (startc != PROPEN && startc != BROPEN) {
3774 	/*
3775 	 * If it's not bounded by braces of some sort, life is much simpler.
3776 	 * We just need to check for the first character and return the
3777 	 * value if it exists.
3778 	 */
3779 
3780 	/* Error out some really stupid names */
3781 	if (startc == '\0' || strchr(")}:$", startc)) {
3782 	    *lengthPtr = 1;
3783 	    return var_Error;
3784 	}
3785 	name[0] = startc;
3786 	name[1] = '\0';
3787 
3788 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3789 	if (v == NULL) {
3790 	    *lengthPtr = 2;
3791 
3792 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
3793 		/*
3794 		 * If substituting a local variable in a non-local context,
3795 		 * assume it's for dynamic source stuff. We have to handle
3796 		 * this specially and return the longhand for the variable
3797 		 * with the dollar sign escaped so it makes it back to the
3798 		 * caller. Only four of the local variables are treated
3799 		 * specially as they are the only four that will be set
3800 		 * when dynamic sources are expanded.
3801 		 */
3802 		switch (str[1]) {
3803 		    case '@':
3804 			return UNCONST("$(.TARGET)");
3805 		    case '%':
3806 			return UNCONST("$(.MEMBER)");
3807 		    case '*':
3808 			return UNCONST("$(.PREFIX)");
3809 		    case '!':
3810 			return UNCONST("$(.ARCHIVE)");
3811 		}
3812 	    }
3813 	    /*
3814 	     * Error
3815 	     */
3816 	    return (flags & VARF_UNDEFERR) ? var_Error : varNoError;
3817 	} else {
3818 	    haveModifier = FALSE;
3819 	    tstr = &str[1];
3820 	    endc = str[1];
3821 	}
3822     } else {
3823 	Buffer buf;	/* Holds the variable name */
3824 	int depth = 1;
3825 
3826 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
3827 	Buf_Init(&buf, 0);
3828 
3829 	/*
3830 	 * Skip to the end character or a colon, whichever comes first.
3831 	 */
3832 	for (tstr = str + 2; *tstr != '\0'; tstr++)
3833 	{
3834 	    /*
3835 	     * Track depth so we can spot parse errors.
3836 	     */
3837 	    if (*tstr == startc) {
3838 		depth++;
3839 	    }
3840 	    if (*tstr == endc) {
3841 		if (--depth == 0)
3842 		    break;
3843 	    }
3844 	    if (depth == 1 && *tstr == ':') {
3845 		break;
3846 	    }
3847 	    /*
3848 	     * A variable inside a variable, expand
3849 	     */
3850 	    if (*tstr == '$') {
3851 		int rlen;
3852 		void *freeIt;
3853 		char *rval = Var_Parse(tstr, ctxt, flags,  &rlen, &freeIt);
3854 		if (rval != NULL) {
3855 		    Buf_AddBytes(&buf, strlen(rval), rval);
3856 		}
3857 		free(freeIt);
3858 		tstr += rlen - 1;
3859 	    }
3860 	    else
3861 		Buf_AddByte(&buf, *tstr);
3862 	}
3863 	if (*tstr == ':') {
3864 	    haveModifier = TRUE;
3865 	} else if (*tstr == endc) {
3866 	    haveModifier = FALSE;
3867 	} else {
3868 	    /*
3869 	     * If we never did find the end character, return NULL
3870 	     * right now, setting the length to be the distance to
3871 	     * the end of the string, since that's what make does.
3872 	     */
3873 	    *lengthPtr = tstr - str;
3874 	    Buf_Destroy(&buf, TRUE);
3875 	    return (var_Error);
3876 	}
3877 	str = Buf_GetAll(&buf, &vlen);
3878 
3879 	/*
3880 	 * At this point, str points into newly allocated memory from
3881 	 * buf, containing only the name of the variable.
3882 	 *
3883 	 * start and tstr point into the const string that was pointed
3884 	 * to by the original value of the str parameter.  start points
3885 	 * to the '$' at the beginning of the string, while tstr points
3886 	 * to the char just after the end of the variable name -- this
3887 	 * will be '\0', ':', PRCLOSE, or BRCLOSE.
3888 	 */
3889 
3890 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3891 	/*
3892 	 * Check also for bogus D and F forms of local variables since we're
3893 	 * in a local context and the name is the right length.
3894 	 */
3895 	if ((v == NULL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
3896 		(vlen == 2) && (str[1] == 'F' || str[1] == 'D') &&
3897 		strchr("@%?*!<>", str[0]) != NULL) {
3898 	    /*
3899 	     * Well, it's local -- go look for it.
3900 	     */
3901 	    name[0] = *str;
3902 	    name[1] = '\0';
3903 	    v = VarFind(name, ctxt, 0);
3904 
3905 	    if (v != NULL) {
3906 		if (str[1] == 'D') {
3907 			extramodifiers = "H:";
3908 		}
3909 		else { /* F */
3910 			extramodifiers = "T:";
3911 		}
3912 	    }
3913 	}
3914 
3915 	if (v == NULL) {
3916 	    if (((vlen == 1) ||
3917 		 (((vlen == 2) && (str[1] == 'F' || str[1] == 'D')))) &&
3918 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3919 	    {
3920 		/*
3921 		 * If substituting a local variable in a non-local context,
3922 		 * assume it's for dynamic source stuff. We have to handle
3923 		 * this specially and return the longhand for the variable
3924 		 * with the dollar sign escaped so it makes it back to the
3925 		 * caller. Only four of the local variables are treated
3926 		 * specially as they are the only four that will be set
3927 		 * when dynamic sources are expanded.
3928 		 */
3929 		switch (*str) {
3930 		    case '@':
3931 		    case '%':
3932 		    case '*':
3933 		    case '!':
3934 			dynamic = TRUE;
3935 			break;
3936 		}
3937 	    } else if ((vlen > 2) && (*str == '.') &&
3938 		       isupper((unsigned char) str[1]) &&
3939 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3940 	    {
3941 		int	len;
3942 
3943 		len = vlen - 1;
3944 		if ((strncmp(str, ".TARGET", len) == 0) ||
3945 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
3946 		    (strncmp(str, ".PREFIX", len) == 0) ||
3947 		    (strncmp(str, ".MEMBER", len) == 0))
3948 		{
3949 		    dynamic = TRUE;
3950 		}
3951 	    }
3952 
3953 	    if (!haveModifier) {
3954 		/*
3955 		 * No modifiers -- have specification length so we can return
3956 		 * now.
3957 		 */
3958 		*lengthPtr = tstr - start + 1;
3959 		if (dynamic) {
3960 		    char *pstr = bmake_strndup(start, *lengthPtr);
3961 		    *freePtr = pstr;
3962 		    Buf_Destroy(&buf, TRUE);
3963 		    return(pstr);
3964 		} else {
3965 		    Buf_Destroy(&buf, TRUE);
3966 		    return (flags & VARF_UNDEFERR) ? var_Error : varNoError;
3967 		}
3968 	    } else {
3969 		/*
3970 		 * Still need to get to the end of the variable specification,
3971 		 * so kludge up a Var structure for the modifications
3972 		 */
3973 		v = bmake_malloc(sizeof(Var));
3974 		v->name = UNCONST(str);
3975 		Buf_Init(&v->val, 1);
3976 		v->flags = VAR_JUNK;
3977 		Buf_Destroy(&buf, FALSE);
3978 	    }
3979 	} else
3980 	    Buf_Destroy(&buf, TRUE);
3981     }
3982 
3983     if (v->flags & VAR_IN_USE) {
3984 	Fatal("Variable %s is recursive.", v->name);
3985 	/*NOTREACHED*/
3986     } else {
3987 	v->flags |= VAR_IN_USE;
3988     }
3989     /*
3990      * Before doing any modification, we have to make sure the value
3991      * has been fully expanded. If it looks like recursion might be
3992      * necessary (there's a dollar sign somewhere in the variable's value)
3993      * we just call Var_Subst to do any other substitutions that are
3994      * necessary. Note that the value returned by Var_Subst will have
3995      * been dynamically-allocated, so it will need freeing when we
3996      * return.
3997      */
3998     nstr = Buf_GetAll(&v->val, NULL);
3999     if (strchr(nstr, '$') != NULL) {
4000 	nstr = Var_Subst(NULL, nstr, ctxt, flags);
4001 	*freePtr = nstr;
4002     }
4003 
4004     v->flags &= ~VAR_IN_USE;
4005 
4006     if ((nstr != NULL) && (haveModifier || extramodifiers != NULL)) {
4007 	void *extraFree;
4008 	int used;
4009 
4010 	extraFree = NULL;
4011 	if (extramodifiers != NULL) {
4012 		nstr = ApplyModifiers(nstr, extramodifiers, '(', ')',
4013 				      v, ctxt, flags, &used, &extraFree);
4014 	}
4015 
4016 	if (haveModifier) {
4017 		/* Skip initial colon. */
4018 		tstr++;
4019 
4020 		nstr = ApplyModifiers(nstr, tstr, startc, endc,
4021 				      v, ctxt, flags, &used, freePtr);
4022 		tstr += used;
4023 		free(extraFree);
4024 	} else {
4025 		*freePtr = extraFree;
4026 	}
4027     }
4028     if (*tstr) {
4029 	*lengthPtr = tstr - start + 1;
4030     } else {
4031 	*lengthPtr = tstr - start;
4032     }
4033 
4034     if (v->flags & VAR_FROM_ENV) {
4035 	Boolean	  destroy = FALSE;
4036 
4037 	if (nstr != Buf_GetAll(&v->val, NULL)) {
4038 	    destroy = TRUE;
4039 	} else {
4040 	    /*
4041 	     * Returning the value unmodified, so tell the caller to free
4042 	     * the thing.
4043 	     */
4044 	    *freePtr = nstr;
4045 	}
4046 	VarFreeEnv(v, destroy);
4047     } else if (v->flags & VAR_JUNK) {
4048 	/*
4049 	 * Perform any free'ing needed and set *freePtr to NULL so the caller
4050 	 * doesn't try to free a static pointer.
4051 	 * If VAR_KEEP is also set then we want to keep str as is.
4052 	 */
4053 	if (!(v->flags & VAR_KEEP)) {
4054 	    if (*freePtr) {
4055 		free(nstr);
4056 		*freePtr = NULL;
4057 	    }
4058 	    if (dynamic) {
4059 		nstr = bmake_strndup(start, *lengthPtr);
4060 		*freePtr = nstr;
4061 	    } else {
4062 		nstr = (flags & VARF_UNDEFERR) ? var_Error : varNoError;
4063 	    }
4064 	}
4065 	if (nstr != Buf_GetAll(&v->val, NULL))
4066 	    Buf_Destroy(&v->val, TRUE);
4067 	free(v->name);
4068 	free(v);
4069     }
4070     return (nstr);
4071 }
4072 
4073 /*-
4074  *-----------------------------------------------------------------------
4075  * Var_Subst  --
4076  *	Substitute for all variables in the given string in the given context
4077  *	If flags & VARF_UNDEFERR, Parse_Error will be called when an undefined
4078  *	variable is encountered.
4079  *
4080  * Input:
4081  *	var		Named variable || NULL for all
4082  *	str		the string which to substitute
4083  *	ctxt		the context wherein to find variables
4084  *	flags		VARF_UNDEFERR	if undefineds are an error
4085  *			VARF_WANTRES	if we actually want the result
4086  *			VARF_ASSIGN	if we are in a := assignment
4087  *
4088  * Results:
4089  *	The resulting string.
4090  *
4091  * Side Effects:
4092  *	None. The old string must be freed by the caller
4093  *-----------------------------------------------------------------------
4094  */
4095 char *
4096 Var_Subst(const char *var, const char *str, GNode *ctxt, int flags)
4097 {
4098     Buffer  	  buf;		    /* Buffer for forming things */
4099     char    	  *val;		    /* Value to substitute for a variable */
4100     int		  length;   	    /* Length of the variable invocation */
4101     Boolean	  trailingBslash;   /* variable ends in \ */
4102     void 	  *freeIt = NULL;    /* Set if it should be freed */
4103     static Boolean errorReported;   /* Set true if an error has already
4104 				     * been reported to prevent a plethora
4105 				     * of messages when recursing */
4106 
4107     Buf_Init(&buf, 0);
4108     errorReported = FALSE;
4109     trailingBslash = FALSE;
4110 
4111     while (*str) {
4112 	if (*str == '\n' && trailingBslash)
4113 	    Buf_AddByte(&buf, ' ');
4114 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
4115 	    /*
4116 	     * A dollar sign may be escaped either with another dollar sign.
4117 	     * In such a case, we skip over the escape character and store the
4118 	     * dollar sign into the buffer directly.
4119 	     */
4120 	    if (save_dollars && (flags & VARF_ASSIGN))
4121 		Buf_AddByte(&buf, *str);
4122 	    str++;
4123 	    Buf_AddByte(&buf, *str);
4124 	    str++;
4125 	} else if (*str != '$') {
4126 	    /*
4127 	     * Skip as many characters as possible -- either to the end of
4128 	     * the string or to the next dollar sign (variable invocation).
4129 	     */
4130 	    const char  *cp;
4131 
4132 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
4133 		continue;
4134 	    Buf_AddBytes(&buf, str - cp, cp);
4135 	} else {
4136 	    if (var != NULL) {
4137 		int expand;
4138 		for (;;) {
4139 		    if (str[1] == '\0') {
4140 			/* A trailing $ is kind of a special case */
4141 			Buf_AddByte(&buf, str[0]);
4142 			str++;
4143 			expand = FALSE;
4144 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
4145 			if (str[1] != *var || strlen(var) > 1) {
4146 			    Buf_AddBytes(&buf, 2, str);
4147 			    str += 2;
4148 			    expand = FALSE;
4149 			}
4150 			else
4151 			    expand = TRUE;
4152 			break;
4153 		    }
4154 		    else {
4155 			const char *p;
4156 
4157 			/*
4158 			 * Scan up to the end of the variable name.
4159 			 */
4160 			for (p = &str[2]; *p &&
4161 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
4162 			    if (*p == '$')
4163 				break;
4164 			/*
4165 			 * A variable inside the variable. We cannot expand
4166 			 * the external variable yet, so we try again with
4167 			 * the nested one
4168 			 */
4169 			if (*p == '$') {
4170 			    Buf_AddBytes(&buf, p - str, str);
4171 			    str = p;
4172 			    continue;
4173 			}
4174 
4175 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
4176 			    var[p - str - 2] != '\0') {
4177 			    /*
4178 			     * Not the variable we want to expand, scan
4179 			     * until the next variable
4180 			     */
4181 			    for (;*p != '$' && *p != '\0'; p++)
4182 				continue;
4183 			    Buf_AddBytes(&buf, p - str, str);
4184 			    str = p;
4185 			    expand = FALSE;
4186 			}
4187 			else
4188 			    expand = TRUE;
4189 			break;
4190 		    }
4191 		}
4192 		if (!expand)
4193 		    continue;
4194 	    }
4195 
4196 	    val = Var_Parse(str, ctxt, flags, &length, &freeIt);
4197 
4198 	    /*
4199 	     * When we come down here, val should either point to the
4200 	     * value of this variable, suitably modified, or be NULL.
4201 	     * Length should be the total length of the potential
4202 	     * variable invocation (from $ to end character...)
4203 	     */
4204 	    if (val == var_Error || val == varNoError) {
4205 		/*
4206 		 * If performing old-time variable substitution, skip over
4207 		 * the variable and continue with the substitution. Otherwise,
4208 		 * store the dollar sign and advance str so we continue with
4209 		 * the string...
4210 		 */
4211 		if (oldVars) {
4212 		    str += length;
4213 		} else if ((flags & VARF_UNDEFERR) || val == var_Error) {
4214 		    /*
4215 		     * If variable is undefined, complain and skip the
4216 		     * variable. The complaint will stop us from doing anything
4217 		     * when the file is parsed.
4218 		     */
4219 		    if (!errorReported) {
4220 			Parse_Error(PARSE_FATAL,
4221 				     "Undefined variable \"%.*s\"",length,str);
4222 		    }
4223 		    str += length;
4224 		    errorReported = TRUE;
4225 		} else {
4226 		    Buf_AddByte(&buf, *str);
4227 		    str += 1;
4228 		}
4229 	    } else {
4230 		/*
4231 		 * We've now got a variable structure to store in. But first,
4232 		 * advance the string pointer.
4233 		 */
4234 		str += length;
4235 
4236 		/*
4237 		 * Copy all the characters from the variable value straight
4238 		 * into the new string.
4239 		 */
4240 		length = strlen(val);
4241 		Buf_AddBytes(&buf, length, val);
4242 		trailingBslash = length > 0 && val[length - 1] == '\\';
4243 	    }
4244 	    free(freeIt);
4245 	    freeIt = NULL;
4246 	}
4247     }
4248 
4249     return Buf_DestroyCompact(&buf);
4250 }
4251 
4252 /*-
4253  *-----------------------------------------------------------------------
4254  * Var_GetTail --
4255  *	Return the tail from each of a list of words. Used to set the
4256  *	System V local variables.
4257  *
4258  * Input:
4259  *	file		Filename to modify
4260  *
4261  * Results:
4262  *	The resulting string.
4263  *
4264  * Side Effects:
4265  *	None.
4266  *
4267  *-----------------------------------------------------------------------
4268  */
4269 #if 0
4270 char *
4271 Var_GetTail(char *file)
4272 {
4273     return(VarModify(file, VarTail, NULL));
4274 }
4275 
4276 /*-
4277  *-----------------------------------------------------------------------
4278  * Var_GetHead --
4279  *	Find the leading components of a (list of) filename(s).
4280  *	XXX: VarHead does not replace foo by ., as (sun) System V make
4281  *	does.
4282  *
4283  * Input:
4284  *	file		Filename to manipulate
4285  *
4286  * Results:
4287  *	The leading components.
4288  *
4289  * Side Effects:
4290  *	None.
4291  *
4292  *-----------------------------------------------------------------------
4293  */
4294 char *
4295 Var_GetHead(char *file)
4296 {
4297     return(VarModify(file, VarHead, NULL));
4298 }
4299 #endif
4300 
4301 /*-
4302  *-----------------------------------------------------------------------
4303  * Var_Init --
4304  *	Initialize the module
4305  *
4306  * Results:
4307  *	None
4308  *
4309  * Side Effects:
4310  *	The VAR_CMD and VAR_GLOBAL contexts are created
4311  *-----------------------------------------------------------------------
4312  */
4313 void
4314 Var_Init(void)
4315 {
4316     VAR_INTERNAL = Targ_NewGN("Internal");
4317     VAR_GLOBAL = Targ_NewGN("Global");
4318     VAR_CMD = Targ_NewGN("Command");
4319 
4320 }
4321 
4322 
4323 void
4324 Var_End(void)
4325 {
4326 }
4327 
4328 
4329 /****************** PRINT DEBUGGING INFO *****************/
4330 static void
4331 VarPrintVar(void *vp)
4332 {
4333     Var    *v = (Var *)vp;
4334     fprintf(debug_file, "%-16s = %s\n", v->name, Buf_GetAll(&v->val, NULL));
4335 }
4336 
4337 /*-
4338  *-----------------------------------------------------------------------
4339  * Var_Dump --
4340  *	print all variables in a context
4341  *-----------------------------------------------------------------------
4342  */
4343 void
4344 Var_Dump(GNode *ctxt)
4345 {
4346     Hash_Search search;
4347     Hash_Entry *h;
4348 
4349     for (h = Hash_EnumFirst(&ctxt->context, &search);
4350 	 h != NULL;
4351 	 h = Hash_EnumNext(&search)) {
4352 	    VarPrintVar(Hash_GetValue(h));
4353     }
4354 }
4355