xref: /freebsd/contrib/bmake/var.c (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
1 /*	$NetBSD: var.c,v 1.174 2013/05/18 13:12:45 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 1.174 2013/05/18 13:12:45 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 1.174 2013/05/18 13:12:45 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    <inttypes.h>
133 #include    <stdlib.h>
134 #include    <limits.h>
135 #include    <time.h>
136 
137 #include    "make.h"
138 #include    "buf.h"
139 #include    "dir.h"
140 #include    "job.h"
141 
142 /*
143  * XXX transition hack for FreeBSD ports.
144  * bsd.port.mk can set .MAKE.FreeBSD_UL=yes
145  * to cause us to treat :[LU] as aliases for :t[lu]
146  * To be reverted when ports converts to :t[lu] (when 8.3 is EOL)
147  */
148 #define MAKE_FREEBSD_UL ".MAKE.FreeBSD_UL"
149 #ifdef MAKE_FREEBSD_UL
150 static int FreeBSD_UL = FALSE;
151 #endif
152 
153 /*
154  * This lets us tell if we have replaced the original environ
155  * (which we cannot free).
156  */
157 char **savedEnv = NULL;
158 
159 /*
160  * This is a harmless return value for Var_Parse that can be used by Var_Subst
161  * to determine if there was an error in parsing -- easier than returning
162  * a flag, as things outside this module don't give a hoot.
163  */
164 char 	var_Error[] = "";
165 
166 /*
167  * Similar to var_Error, but returned when the 'errnum' flag for Var_Parse is
168  * set false. Why not just use a constant? Well, gcc likes to condense
169  * identical string instances...
170  */
171 static char	varNoError[] = "";
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_GLOBAL;   /* variables from the makefile */
190 GNode          *VAR_CMD;      /* variables defined on the command-line */
191 
192 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
193 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
194 #define FIND_ENV  	0x4   /* look in the environment also */
195 
196 typedef struct Var {
197     char          *name;	/* the variable's name */
198     Buffer	  val;		/* its value */
199     int		  flags;    	/* miscellaneous status flags */
200 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
201 				     * Used to avoid recursion */
202 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
203 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
204 				     * should be destroyed when done with
205 				     * it. Used by Var_Parse for undefined,
206 				     * modified variables */
207 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
208 				     * a use for it in some modifier and
209 				     * the value is therefore valid */
210 #define VAR_EXPORTED	16 	    /* Variable is exported */
211 #define VAR_REEXPORT	32	    /* Indicate if var needs re-export.
212 				     * This would be true if it contains $'s
213 				     */
214 #define VAR_FROM_CMD	64 	    /* Variable came from command line */
215 }  Var;
216 
217 /*
218  * Exporting vars is expensive so skip it if we can
219  */
220 #define VAR_EXPORTED_NONE	0
221 #define VAR_EXPORTED_YES	1
222 #define VAR_EXPORTED_ALL	2
223 static int var_exportedVars = VAR_EXPORTED_NONE;
224 /*
225  * We pass this to Var_Export when doing the initial export
226  * or after updating an exported var.
227  */
228 #define VAR_EXPORT_PARENT 1
229 
230 /* Var*Pattern flags */
231 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
232 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
233 #define VAR_SUB_MATCHED	0x04	/* There was a match */
234 #define VAR_MATCH_START	0x08	/* Match at start of word */
235 #define VAR_MATCH_END	0x10	/* Match at end of word */
236 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
237 
238 /* Var_Set flags */
239 #define VAR_NO_EXPORT	0x01	/* do not export */
240 
241 typedef struct {
242     /*
243      * The following fields are set by Var_Parse() when it
244      * encounters modifiers that need to keep state for use by
245      * subsequent modifiers within the same variable expansion.
246      */
247     Byte	varSpace;	/* Word separator in expansions */
248     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
249 				 * single big word, even if it contains
250 				 * embedded spaces (as opposed to the
251 				 * usual behaviour of treating it as
252 				 * several space-separated words). */
253 } Var_Parse_State;
254 
255 /* struct passed as 'void *' to VarSubstitute() for ":S/lhs/rhs/",
256  * to VarSYSVMatch() for ":lhs=rhs". */
257 typedef struct {
258     const char   *lhs;	    /* String to match */
259     int		  leftLen; /* Length of string */
260     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
261     int		  rightLen; /* Length of replacement */
262     int		  flags;
263 } VarPattern;
264 
265 /* struct passed as 'void *' to VarLoopExpand() for ":@tvar@str@" */
266 typedef struct {
267     GNode	*ctxt;		/* variable context */
268     char	*tvar;		/* name of temp var */
269     int		tvarLen;
270     char	*str;		/* string to expand */
271     int		strLen;
272     int		errnum;		/* errnum for not defined */
273 } VarLoop_t;
274 
275 #ifndef NO_REGEX
276 /* struct passed as 'void *' to VarRESubstitute() for ":C///" */
277 typedef struct {
278     regex_t	   re;
279     int		   nsub;
280     regmatch_t 	  *matches;
281     char 	  *replace;
282     int		   flags;
283 } VarREPattern;
284 #endif
285 
286 /* struct passed to VarSelectWords() for ":[start..end]" */
287 typedef struct {
288     int		start;		/* first word to select */
289     int		end;		/* last word to select */
290 } VarSelectWords_t;
291 
292 static Var *VarFind(const char *, GNode *, int);
293 static void VarAdd(const char *, const char *, GNode *);
294 static Boolean VarHead(GNode *, Var_Parse_State *,
295 			char *, Boolean, Buffer *, void *);
296 static Boolean VarTail(GNode *, Var_Parse_State *,
297 			char *, Boolean, Buffer *, void *);
298 static Boolean VarSuffix(GNode *, Var_Parse_State *,
299 			char *, Boolean, Buffer *, void *);
300 static Boolean VarRoot(GNode *, Var_Parse_State *,
301 			char *, Boolean, Buffer *, void *);
302 static Boolean VarMatch(GNode *, Var_Parse_State *,
303 			char *, Boolean, Buffer *, void *);
304 #ifdef SYSVVARSUB
305 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
306 			char *, Boolean, Buffer *, void *);
307 #endif
308 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
309 			char *, Boolean, Buffer *, void *);
310 #ifndef NO_REGEX
311 static void VarREError(int, regex_t *, const char *);
312 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
313 			char *, Boolean, Buffer *, void *);
314 #endif
315 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
316 			char *, Boolean, Buffer *, void *);
317 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
318 			char *, Boolean, Buffer *, void *);
319 static char *VarGetPattern(GNode *, Var_Parse_State *,
320 			   int, const char **, int, int *, int *,
321 			   VarPattern *);
322 static char *VarQuote(char *);
323 static char *VarHash(char *);
324 static char *VarModify(GNode *, Var_Parse_State *,
325     const char *,
326     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer *, void *),
327     void *);
328 static char *VarOrder(const char *, const char);
329 static char *VarUniq(const char *);
330 static int VarWordCompare(const void *, const void *);
331 static void VarPrintVar(void *);
332 
333 #define BROPEN	'{'
334 #define BRCLOSE	'}'
335 #define PROPEN	'('
336 #define PRCLOSE	')'
337 
338 /*-
339  *-----------------------------------------------------------------------
340  * VarFind --
341  *	Find the given variable in the given context and any other contexts
342  *	indicated.
343  *
344  * Input:
345  *	name		name to find
346  *	ctxt		context in which to find it
347  *	flags		FIND_GLOBAL set means to look in the
348  *			VAR_GLOBAL context as well. FIND_CMD set means
349  *			to look in the VAR_CMD context also. FIND_ENV
350  *			set means to look in the environment
351  *
352  * Results:
353  *	A pointer to the structure describing the desired variable or
354  *	NULL if the variable does not exist.
355  *
356  * Side Effects:
357  *	None
358  *-----------------------------------------------------------------------
359  */
360 static Var *
361 VarFind(const char *name, GNode *ctxt, int flags)
362 {
363     Hash_Entry         	*var;
364     Var			*v;
365 
366 	/*
367 	 * If the variable name begins with a '.', it could very well be one of
368 	 * the local ones.  We check the name against all the local variables
369 	 * and substitute the short version in for 'name' if it matches one of
370 	 * them.
371 	 */
372 	if (*name == '.' && isupper((unsigned char) name[1]))
373 		switch (name[1]) {
374 		case 'A':
375 			if (!strcmp(name, ".ALLSRC"))
376 				name = ALLSRC;
377 			if (!strcmp(name, ".ARCHIVE"))
378 				name = ARCHIVE;
379 			break;
380 		case 'I':
381 			if (!strcmp(name, ".IMPSRC"))
382 				name = IMPSRC;
383 			break;
384 		case 'M':
385 			if (!strcmp(name, ".MEMBER"))
386 				name = MEMBER;
387 			break;
388 		case 'O':
389 			if (!strcmp(name, ".OODATE"))
390 				name = OODATE;
391 			break;
392 		case 'P':
393 			if (!strcmp(name, ".PREFIX"))
394 				name = PREFIX;
395 			break;
396 		case 'T':
397 			if (!strcmp(name, ".TARGET"))
398 				name = TARGET;
399 			break;
400 		}
401 #ifdef notyet
402     /* for compatibility with gmake */
403     if (name[0] == '^' && name[1] == '\0')
404 	    name = ALLSRC;
405 #endif
406 
407     /*
408      * First look for the variable in the given context. If it's not there,
409      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
410      * depending on the FIND_* flags in 'flags'
411      */
412     var = Hash_FindEntry(&ctxt->context, name);
413 
414     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
415 	var = Hash_FindEntry(&VAR_CMD->context, name);
416     }
417     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
418 	(ctxt != VAR_GLOBAL))
419     {
420 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
421     }
422     if ((var == NULL) && (flags & FIND_ENV)) {
423 	char *env;
424 
425 	if ((env = getenv(name)) != NULL) {
426 	    int		len;
427 
428 	    v = bmake_malloc(sizeof(Var));
429 	    v->name = bmake_strdup(name);
430 
431 	    len = strlen(env);
432 
433 	    Buf_Init(&v->val, len + 1);
434 	    Buf_AddBytes(&v->val, len, env);
435 
436 	    v->flags = VAR_FROM_ENV;
437 	    return (v);
438 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
439 		   (ctxt != VAR_GLOBAL))
440 	{
441 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
442 	    if (var == NULL) {
443 		return NULL;
444 	    } else {
445 		return ((Var *)Hash_GetValue(var));
446 	    }
447 	} else {
448 	    return NULL;
449 	}
450     } else if (var == NULL) {
451 	return NULL;
452     } else {
453 	return ((Var *)Hash_GetValue(var));
454     }
455 }
456 
457 /*-
458  *-----------------------------------------------------------------------
459  * VarFreeEnv  --
460  *	If the variable is an environment variable, free it
461  *
462  * Input:
463  *	v		the variable
464  *	destroy		true if the value buffer should be destroyed.
465  *
466  * Results:
467  *	1 if it is an environment variable 0 ow.
468  *
469  * Side Effects:
470  *	The variable is free'ed if it is an environent variable.
471  *-----------------------------------------------------------------------
472  */
473 static Boolean
474 VarFreeEnv(Var *v, Boolean destroy)
475 {
476     if ((v->flags & VAR_FROM_ENV) == 0)
477 	return FALSE;
478     free(v->name);
479     Buf_Destroy(&v->val, destroy);
480     free(v);
481     return TRUE;
482 }
483 
484 /*-
485  *-----------------------------------------------------------------------
486  * VarAdd  --
487  *	Add a new variable of name name and value val to the given context
488  *
489  * Input:
490  *	name		name of variable to add
491  *	val		value to set it to
492  *	ctxt		context in which to set it
493  *
494  * Results:
495  *	None
496  *
497  * Side Effects:
498  *	The new variable is placed at the front of the given context
499  *	The name and val arguments are duplicated so they may
500  *	safely be freed.
501  *-----------------------------------------------------------------------
502  */
503 static void
504 VarAdd(const char *name, const char *val, GNode *ctxt)
505 {
506     Var   	  *v;
507     int		  len;
508     Hash_Entry    *h;
509 
510     v = bmake_malloc(sizeof(Var));
511 
512     len = val ? strlen(val) : 0;
513     Buf_Init(&v->val, len+1);
514     Buf_AddBytes(&v->val, len, val);
515 
516     v->flags = 0;
517 
518     h = Hash_CreateEntry(&ctxt->context, name, NULL);
519     Hash_SetValue(h, v);
520     v->name = h->name;
521     if (DEBUG(VAR)) {
522 	fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
523     }
524 }
525 
526 /*-
527  *-----------------------------------------------------------------------
528  * Var_Delete --
529  *	Remove a variable from a context.
530  *
531  * Results:
532  *	None.
533  *
534  * Side Effects:
535  *	The Var structure is removed and freed.
536  *
537  *-----------------------------------------------------------------------
538  */
539 void
540 Var_Delete(const char *name, GNode *ctxt)
541 {
542     Hash_Entry 	  *ln;
543     char *cp;
544 
545     if (strchr(name, '$')) {
546 	cp = Var_Subst(NULL, name, VAR_GLOBAL, 0);
547     } else {
548 	cp = (char *)name;
549     }
550     ln = Hash_FindEntry(&ctxt->context, cp);
551     if (DEBUG(VAR)) {
552 	fprintf(debug_file, "%s:delete %s%s\n",
553 	    ctxt->name, cp, ln ? "" : " (not found)");
554     }
555     if (cp != name) {
556 	free(cp);
557     }
558     if (ln != NULL) {
559 	Var 	  *v;
560 
561 	v = (Var *)Hash_GetValue(ln);
562 	if ((v->flags & VAR_EXPORTED)) {
563 	    unsetenv(v->name);
564 	}
565 	if (strcmp(MAKE_EXPORTED, v->name) == 0) {
566 	    var_exportedVars = VAR_EXPORTED_NONE;
567 	}
568 	if (v->name != ln->name)
569 		free(v->name);
570 	Hash_DeleteEntry(&ctxt->context, ln);
571 	Buf_Destroy(&v->val, TRUE);
572 	free(v);
573     }
574 }
575 
576 
577 /*
578  * Export a var.
579  * We ignore make internal variables (those which start with '.')
580  * Also we jump through some hoops to avoid calling setenv
581  * more than necessary since it can leak.
582  * We only manipulate flags of vars if 'parent' is set.
583  */
584 static int
585 Var_Export1(const char *name, int parent)
586 {
587     char tmp[BUFSIZ];
588     Var *v;
589     char *val = NULL;
590     int n;
591 
592     if (*name == '.')
593 	return 0;			/* skip internals */
594     if (!name[1]) {
595 	/*
596 	 * A single char.
597 	 * If it is one of the vars that should only appear in
598 	 * local context, skip it, else we can get Var_Subst
599 	 * into a loop.
600 	 */
601 	switch (name[0]) {
602 	case '@':
603 	case '%':
604 	case '*':
605 	case '!':
606 	    return 0;
607 	}
608     }
609     v = VarFind(name, VAR_GLOBAL, 0);
610     if (v == NULL) {
611 	return 0;
612     }
613     if (!parent &&
614 	(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
615 	return 0;			/* nothing to do */
616     }
617     val = Buf_GetAll(&v->val, NULL);
618     if (strchr(val, '$')) {
619 	if (parent) {
620 	    /*
621 	     * Flag this as something we need to re-export.
622 	     * No point actually exporting it now though,
623 	     * the child can do it at the last minute.
624 	     */
625 	    v->flags |= (VAR_EXPORTED|VAR_REEXPORT);
626 	    return 1;
627 	}
628 	if (v->flags & VAR_IN_USE) {
629 	    /*
630 	     * We recursed while exporting in a child.
631 	     * This isn't going to end well, just skip it.
632 	     */
633 	    return 0;
634 	}
635 	n = snprintf(tmp, sizeof(tmp), "${%s}", name);
636 	if (n < (int)sizeof(tmp)) {
637 	    val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
638 	    setenv(name, val, 1);
639 	    free(val);
640 	}
641     } else {
642 	if (parent) {
643 	    v->flags &= ~VAR_REEXPORT;	/* once will do */
644 	}
645 	if (parent || !(v->flags & VAR_EXPORTED)) {
646 	    setenv(name, val, 1);
647 	}
648     }
649     /*
650      * This is so Var_Set knows to call Var_Export again...
651      */
652     if (parent) {
653 	v->flags |= VAR_EXPORTED;
654     }
655     return 1;
656 }
657 
658 /*
659  * This gets called from our children.
660  */
661 void
662 Var_ExportVars(void)
663 {
664     char tmp[BUFSIZ];
665     Hash_Entry         	*var;
666     Hash_Search 	state;
667     Var *v;
668     char *val;
669     int n;
670 
671     if (VAR_EXPORTED_NONE == var_exportedVars)
672 	return;
673 
674     if (VAR_EXPORTED_ALL == var_exportedVars) {
675 	/*
676 	 * Ouch! This is crazy...
677 	 */
678 	for (var = Hash_EnumFirst(&VAR_GLOBAL->context, &state);
679 	     var != NULL;
680 	     var = Hash_EnumNext(&state)) {
681 	    v = (Var *)Hash_GetValue(var);
682 	    Var_Export1(v->name, 0);
683 	}
684 	return;
685     }
686     /*
687      * We have a number of exported vars,
688      */
689     n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
690     if (n < (int)sizeof(tmp)) {
691 	char **av;
692 	char *as;
693 	int ac;
694 	int i;
695 
696 	val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
697 	av = brk_string(val, &ac, FALSE, &as);
698 	for (i = 0; i < ac; i++) {
699 	    Var_Export1(av[i], 0);
700 	}
701 	free(val);
702 	free(as);
703 	free(av);
704     }
705 }
706 
707 /*
708  * This is called when .export is seen or
709  * .MAKE.EXPORTED is modified.
710  * It is also called when any exported var is modified.
711  */
712 void
713 Var_Export(char *str, int isExport)
714 {
715     char *name;
716     char *val;
717     char **av;
718     char *as;
719     int track;
720     int ac;
721     int i;
722 
723     if (isExport && (!str || !str[0])) {
724 	var_exportedVars = VAR_EXPORTED_ALL; /* use with caution! */
725 	return;
726     }
727 
728     if (strncmp(str, "-env", 4) == 0) {
729 	track = 0;
730 	str += 4;
731     } else {
732 	track = VAR_EXPORT_PARENT;
733     }
734     val = Var_Subst(NULL, str, VAR_GLOBAL, 0);
735     av = brk_string(val, &ac, FALSE, &as);
736     for (i = 0; i < ac; i++) {
737 	name = av[i];
738 	if (!name[1]) {
739 	    /*
740 	     * A single char.
741 	     * If it is one of the vars that should only appear in
742 	     * local context, skip it, else we can get Var_Subst
743 	     * into a loop.
744 	     */
745 	    switch (name[0]) {
746 	    case '@':
747 	    case '%':
748 	    case '*':
749 	    case '!':
750 		continue;
751 	    }
752 	}
753 	if (Var_Export1(name, track)) {
754 	    if (VAR_EXPORTED_ALL != var_exportedVars)
755 		var_exportedVars = VAR_EXPORTED_YES;
756 	    if (isExport && track) {
757 		Var_Append(MAKE_EXPORTED, name, VAR_GLOBAL);
758 	    }
759 	}
760     }
761     free(val);
762     free(as);
763     free(av);
764 }
765 
766 
767 /*
768  * This is called when .unexport[-env] is seen.
769  */
770 extern char **environ;
771 
772 void
773 Var_UnExport(char *str)
774 {
775     char tmp[BUFSIZ];
776     char *vlist;
777     char *cp;
778     Boolean unexport_env;
779     int n;
780 
781     if (!str || !str[0]) {
782 	return; 			/* assert? */
783     }
784 
785     vlist = NULL;
786 
787     str += 8;
788     unexport_env = (strncmp(str, "-env", 4) == 0);
789     if (unexport_env) {
790 	char **newenv;
791 
792 	cp = getenv(MAKE_LEVEL);	/* we should preserve this */
793 	if (environ == savedEnv) {
794 	    /* we have been here before! */
795 	    newenv = bmake_realloc(environ, 2 * sizeof(char *));
796 	} else {
797 	    if (savedEnv) {
798 		free(savedEnv);
799 		savedEnv = NULL;
800 	    }
801 	    newenv = bmake_malloc(2 * sizeof(char *));
802 	}
803 	if (!newenv)
804 	    return;
805 	/* Note: we cannot safely free() the original environ. */
806 	environ = savedEnv = newenv;
807 	newenv[0] = NULL;
808 	newenv[1] = NULL;
809 	setenv(MAKE_LEVEL, cp, 1);
810 #ifdef MAKE_LEVEL_SAFE
811 	setenv(MAKE_LEVEL_SAFE, cp, 1);
812 #endif
813     } else {
814 	for (; *str != '\n' && isspace((unsigned char) *str); str++)
815 	    continue;
816 	if (str[0] && str[0] != '\n') {
817 	    vlist = str;
818 	}
819     }
820 
821     if (!vlist) {
822 	/* Using .MAKE.EXPORTED */
823 	n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
824 	if (n < (int)sizeof(tmp)) {
825 	    vlist = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
826 	}
827     }
828     if (vlist) {
829 	Var *v;
830 	char **av;
831 	char *as;
832 	int ac;
833 	int i;
834 
835 	av = brk_string(vlist, &ac, FALSE, &as);
836 	for (i = 0; i < ac; i++) {
837 	    v = VarFind(av[i], VAR_GLOBAL, 0);
838 	    if (!v)
839 		continue;
840 	    if (!unexport_env &&
841 		(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
842 		unsetenv(v->name);
843 	    }
844 	    v->flags &= ~(VAR_EXPORTED|VAR_REEXPORT);
845 	    /*
846 	     * If we are unexporting a list,
847 	     * remove each one from .MAKE.EXPORTED.
848 	     * If we are removing them all,
849 	     * just delete .MAKE.EXPORTED below.
850 	     */
851 	    if (vlist == str) {
852 		n = snprintf(tmp, sizeof(tmp),
853 			     "${" MAKE_EXPORTED ":N%s}", v->name);
854 		if (n < (int)sizeof(tmp)) {
855 		    cp = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
856 		    Var_Set(MAKE_EXPORTED, cp, VAR_GLOBAL, 0);
857 		    free(cp);
858 		}
859 	    }
860 	}
861 	free(as);
862 	free(av);
863 	if (vlist != str) {
864 	    Var_Delete(MAKE_EXPORTED, VAR_GLOBAL);
865 	    free(vlist);
866 	}
867     }
868 }
869 
870 /*-
871  *-----------------------------------------------------------------------
872  * Var_Set --
873  *	Set the variable name to the value val in the given context.
874  *
875  * Input:
876  *	name		name of variable to set
877  *	val		value to give to the variable
878  *	ctxt		context in which to set it
879  *
880  * Results:
881  *	None.
882  *
883  * Side Effects:
884  *	If the variable doesn't yet exist, a new record is created for it.
885  *	Else the old value is freed and the new one stuck in its place
886  *
887  * Notes:
888  *	The variable is searched for only in its context before being
889  *	created in that context. I.e. if the context is VAR_GLOBAL,
890  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
891  *	VAR_CMD->context is searched. This is done to avoid the literally
892  *	thousands of unnecessary strcmp's that used to be done to
893  *	set, say, $(@) or $(<).
894  *	If the context is VAR_GLOBAL though, we check if the variable
895  *	was set in VAR_CMD from the command line and skip it if so.
896  *-----------------------------------------------------------------------
897  */
898 void
899 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
900 {
901     Var   *v;
902     char *expanded_name = NULL;
903 
904     /*
905      * We only look for a variable in the given context since anything set
906      * here will override anything in a lower context, so there's not much
907      * point in searching them all just to save a bit of memory...
908      */
909     if (strchr(name, '$') != NULL) {
910 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
911 	if (expanded_name[0] == 0) {
912 	    if (DEBUG(VAR)) {
913 		fprintf(debug_file, "Var_Set(\"%s\", \"%s\", ...) "
914 			"name expands to empty string - ignored\n",
915 			name, val);
916 	    }
917 	    free(expanded_name);
918 	    return;
919 	}
920 	name = expanded_name;
921     }
922     if (ctxt == VAR_GLOBAL) {
923 	v = VarFind(name, VAR_CMD, 0);
924 	if (v != NULL) {
925 	    if ((v->flags & VAR_FROM_CMD)) {
926 		if (DEBUG(VAR)) {
927 		    fprintf(debug_file, "%s:%s = %s ignored!\n", ctxt->name, name, val);
928 		}
929 		goto out;
930 	    }
931 	    VarFreeEnv(v, TRUE);
932 	}
933     }
934     v = VarFind(name, ctxt, 0);
935     if (v == NULL) {
936 	VarAdd(name, val, ctxt);
937     } else {
938 	Buf_Empty(&v->val);
939 	Buf_AddBytes(&v->val, strlen(val), val);
940 
941 	if (DEBUG(VAR)) {
942 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
943 	}
944 	if ((v->flags & VAR_EXPORTED)) {
945 	    Var_Export1(name, VAR_EXPORT_PARENT);
946 	}
947     }
948     /*
949      * Any variables given on the command line are automatically exported
950      * to the environment (as per POSIX standard)
951      */
952     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
953 	if (v == NULL) {
954 	    /* we just added it */
955 	    v = VarFind(name, ctxt, 0);
956 	}
957 	if (v != NULL)
958 	    v->flags |= VAR_FROM_CMD;
959 	/*
960 	 * If requested, don't export these in the environment
961 	 * individually.  We still put them in MAKEOVERRIDES so
962 	 * that the command-line settings continue to override
963 	 * Makefile settings.
964 	 */
965 	if (varNoExportEnv != TRUE)
966 	    setenv(name, val, 1);
967 
968 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
969     }
970     /*
971      * Another special case.
972      * Several make's support this sort of mechanism for tracking
973      * recursion - but each uses a different name.
974      * We allow the makefiles to update .MAKE.LEVEL and ensure
975      * children see a correctly incremented value.
976      */
977     if (ctxt == VAR_GLOBAL && strcmp(MAKE_LEVEL, name) == 0) {
978 	char tmp[64];
979 	int level;
980 
981 	level = atoi(val);
982 	snprintf(tmp, sizeof(tmp), "%u", level + 1);
983 	setenv(MAKE_LEVEL, tmp, 1);
984 #ifdef MAKE_LEVEL_SAFE
985 	setenv(MAKE_LEVEL_SAFE, tmp, 1);
986 #endif
987     }
988 #ifdef MAKE_FREEBSD_UL
989     if (strcmp(MAKE_FREEBSD_UL, name) == 0) {
990 	FreeBSD_UL = getBoolean(MAKE_FREEBSD_UL, FALSE);
991     }
992 #endif
993 
994 
995  out:
996     if (expanded_name != NULL)
997 	free(expanded_name);
998     if (v != NULL)
999 	VarFreeEnv(v, TRUE);
1000 }
1001 
1002 /*-
1003  *-----------------------------------------------------------------------
1004  * Var_Append --
1005  *	The variable of the given name has the given value appended to it in
1006  *	the given context.
1007  *
1008  * Input:
1009  *	name		name of variable to modify
1010  *	val		String to append to it
1011  *	ctxt		Context in which this should occur
1012  *
1013  * Results:
1014  *	None
1015  *
1016  * Side Effects:
1017  *	If the variable doesn't exist, it is created. Else the strings
1018  *	are concatenated (with a space in between).
1019  *
1020  * Notes:
1021  *	Only if the variable is being sought in the global context is the
1022  *	environment searched.
1023  *	XXX: Knows its calling circumstances in that if called with ctxt
1024  *	an actual target, it will only search that context since only
1025  *	a local variable could be being appended to. This is actually
1026  *	a big win and must be tolerated.
1027  *-----------------------------------------------------------------------
1028  */
1029 void
1030 Var_Append(const char *name, const char *val, GNode *ctxt)
1031 {
1032     Var		   *v;
1033     Hash_Entry	   *h;
1034     char *expanded_name = NULL;
1035 
1036     if (strchr(name, '$') != NULL) {
1037 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
1038 	if (expanded_name[0] == 0) {
1039 	    if (DEBUG(VAR)) {
1040 		fprintf(debug_file, "Var_Append(\"%s\", \"%s\", ...) "
1041 			"name expands to empty string - ignored\n",
1042 			name, val);
1043 	    }
1044 	    free(expanded_name);
1045 	    return;
1046 	}
1047 	name = expanded_name;
1048     }
1049 
1050     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
1051 
1052     if (v == NULL) {
1053 	VarAdd(name, val, ctxt);
1054     } else {
1055 	Buf_AddByte(&v->val, ' ');
1056 	Buf_AddBytes(&v->val, strlen(val), val);
1057 
1058 	if (DEBUG(VAR)) {
1059 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name,
1060 		   Buf_GetAll(&v->val, NULL));
1061 	}
1062 
1063 	if (v->flags & VAR_FROM_ENV) {
1064 	    /*
1065 	     * If the original variable came from the environment, we
1066 	     * have to install it in the global context (we could place
1067 	     * it in the environment, but then we should provide a way to
1068 	     * export other variables...)
1069 	     */
1070 	    v->flags &= ~VAR_FROM_ENV;
1071 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
1072 	    Hash_SetValue(h, v);
1073 	}
1074     }
1075     if (expanded_name != NULL)
1076 	free(expanded_name);
1077 }
1078 
1079 /*-
1080  *-----------------------------------------------------------------------
1081  * Var_Exists --
1082  *	See if the given variable exists.
1083  *
1084  * Input:
1085  *	name		Variable to find
1086  *	ctxt		Context in which to start search
1087  *
1088  * Results:
1089  *	TRUE if it does, FALSE if it doesn't
1090  *
1091  * Side Effects:
1092  *	None.
1093  *
1094  *-----------------------------------------------------------------------
1095  */
1096 Boolean
1097 Var_Exists(const char *name, GNode *ctxt)
1098 {
1099     Var		  *v;
1100     char          *cp;
1101 
1102     if ((cp = strchr(name, '$')) != NULL) {
1103 	cp = Var_Subst(NULL, name, ctxt, FALSE);
1104     }
1105     v = VarFind(cp ? cp : name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
1106     if (cp != NULL) {
1107 	free(cp);
1108     }
1109     if (v == NULL) {
1110 	return(FALSE);
1111     } else {
1112 	(void)VarFreeEnv(v, TRUE);
1113     }
1114     return(TRUE);
1115 }
1116 
1117 /*-
1118  *-----------------------------------------------------------------------
1119  * Var_Value --
1120  *	Return the value of the named variable in the given context
1121  *
1122  * Input:
1123  *	name		name to find
1124  *	ctxt		context in which to search for it
1125  *
1126  * Results:
1127  *	The value if the variable exists, NULL if it doesn't
1128  *
1129  * Side Effects:
1130  *	None
1131  *-----------------------------------------------------------------------
1132  */
1133 char *
1134 Var_Value(const char *name, GNode *ctxt, char **frp)
1135 {
1136     Var            *v;
1137 
1138     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
1139     *frp = NULL;
1140     if (v != NULL) {
1141 	char *p = (Buf_GetAll(&v->val, NULL));
1142 	if (VarFreeEnv(v, FALSE))
1143 	    *frp = p;
1144 	return p;
1145     } else {
1146 	return NULL;
1147     }
1148 }
1149 
1150 /*-
1151  *-----------------------------------------------------------------------
1152  * VarHead --
1153  *	Remove the tail of the given word and place the result in the given
1154  *	buffer.
1155  *
1156  * Input:
1157  *	word		Word to trim
1158  *	addSpace	True if need to add a space to the buffer
1159  *			before sticking in the head
1160  *	buf		Buffer in which to store it
1161  *
1162  * Results:
1163  *	TRUE if characters were added to the buffer (a space needs to be
1164  *	added to the buffer before the next word).
1165  *
1166  * Side Effects:
1167  *	The trimmed word is added to the buffer.
1168  *
1169  *-----------------------------------------------------------------------
1170  */
1171 static Boolean
1172 VarHead(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1173 	char *word, Boolean addSpace, Buffer *buf,
1174 	void *dummy)
1175 {
1176     char *slash;
1177 
1178     slash = strrchr(word, '/');
1179     if (slash != NULL) {
1180 	if (addSpace && vpstate->varSpace) {
1181 	    Buf_AddByte(buf, vpstate->varSpace);
1182 	}
1183 	*slash = '\0';
1184 	Buf_AddBytes(buf, strlen(word), word);
1185 	*slash = '/';
1186 	return (TRUE);
1187     } else {
1188 	/*
1189 	 * If no directory part, give . (q.v. the POSIX standard)
1190 	 */
1191 	if (addSpace && vpstate->varSpace)
1192 	    Buf_AddByte(buf, vpstate->varSpace);
1193 	Buf_AddByte(buf, '.');
1194     }
1195     return(dummy ? TRUE : TRUE);
1196 }
1197 
1198 /*-
1199  *-----------------------------------------------------------------------
1200  * VarTail --
1201  *	Remove the head of the given word and place the result in the given
1202  *	buffer.
1203  *
1204  * Input:
1205  *	word		Word to trim
1206  *	addSpace	True if need to add a space to the buffer
1207  *			before adding the tail
1208  *	buf		Buffer in which to store it
1209  *
1210  * Results:
1211  *	TRUE if characters were added to the buffer (a space needs to be
1212  *	added to the buffer before the next word).
1213  *
1214  * Side Effects:
1215  *	The trimmed word is added to the buffer.
1216  *
1217  *-----------------------------------------------------------------------
1218  */
1219 static Boolean
1220 VarTail(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1221 	char *word, Boolean addSpace, Buffer *buf,
1222 	void *dummy)
1223 {
1224     char *slash;
1225 
1226     if (addSpace && vpstate->varSpace) {
1227 	Buf_AddByte(buf, vpstate->varSpace);
1228     }
1229 
1230     slash = strrchr(word, '/');
1231     if (slash != NULL) {
1232 	*slash++ = '\0';
1233 	Buf_AddBytes(buf, strlen(slash), slash);
1234 	slash[-1] = '/';
1235     } else {
1236 	Buf_AddBytes(buf, strlen(word), word);
1237     }
1238     return (dummy ? TRUE : TRUE);
1239 }
1240 
1241 /*-
1242  *-----------------------------------------------------------------------
1243  * VarSuffix --
1244  *	Place the suffix of the given word in the given buffer.
1245  *
1246  * Input:
1247  *	word		Word to trim
1248  *	addSpace	TRUE if need to add a space before placing the
1249  *			suffix in the buffer
1250  *	buf		Buffer in which to store it
1251  *
1252  * Results:
1253  *	TRUE if characters were added to the buffer (a space needs to be
1254  *	added to the buffer before the next word).
1255  *
1256  * Side Effects:
1257  *	The suffix from the word is placed in the buffer.
1258  *
1259  *-----------------------------------------------------------------------
1260  */
1261 static Boolean
1262 VarSuffix(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1263 	  char *word, Boolean addSpace, Buffer *buf,
1264 	  void *dummy)
1265 {
1266     char *dot;
1267 
1268     dot = strrchr(word, '.');
1269     if (dot != NULL) {
1270 	if (addSpace && vpstate->varSpace) {
1271 	    Buf_AddByte(buf, vpstate->varSpace);
1272 	}
1273 	*dot++ = '\0';
1274 	Buf_AddBytes(buf, strlen(dot), dot);
1275 	dot[-1] = '.';
1276 	addSpace = TRUE;
1277     }
1278     return (dummy ? addSpace : addSpace);
1279 }
1280 
1281 /*-
1282  *-----------------------------------------------------------------------
1283  * VarRoot --
1284  *	Remove the suffix of the given word and place the result in the
1285  *	buffer.
1286  *
1287  * Input:
1288  *	word		Word to trim
1289  *	addSpace	TRUE if need to add a space to the buffer
1290  *			before placing the root in it
1291  *	buf		Buffer in which to store it
1292  *
1293  * Results:
1294  *	TRUE if characters were added to the buffer (a space needs to be
1295  *	added to the buffer before the next word).
1296  *
1297  * Side Effects:
1298  *	The trimmed word is added to the buffer.
1299  *
1300  *-----------------------------------------------------------------------
1301  */
1302 static Boolean
1303 VarRoot(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1304 	char *word, Boolean addSpace, Buffer *buf,
1305 	void *dummy)
1306 {
1307     char *dot;
1308 
1309     if (addSpace && vpstate->varSpace) {
1310 	Buf_AddByte(buf, vpstate->varSpace);
1311     }
1312 
1313     dot = strrchr(word, '.');
1314     if (dot != NULL) {
1315 	*dot = '\0';
1316 	Buf_AddBytes(buf, strlen(word), word);
1317 	*dot = '.';
1318     } else {
1319 	Buf_AddBytes(buf, strlen(word), word);
1320     }
1321     return (dummy ? TRUE : TRUE);
1322 }
1323 
1324 /*-
1325  *-----------------------------------------------------------------------
1326  * VarMatch --
1327  *	Place the word in the buffer if it matches the given pattern.
1328  *	Callback function for VarModify to implement the :M modifier.
1329  *
1330  * Input:
1331  *	word		Word to examine
1332  *	addSpace	TRUE if need to add a space to the buffer
1333  *			before adding the word, if it matches
1334  *	buf		Buffer in which to store it
1335  *	pattern		Pattern the word must match
1336  *
1337  * Results:
1338  *	TRUE if a space should be placed in the buffer before the next
1339  *	word.
1340  *
1341  * Side Effects:
1342  *	The word may be copied to the buffer.
1343  *
1344  *-----------------------------------------------------------------------
1345  */
1346 static Boolean
1347 VarMatch(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1348 	 char *word, Boolean addSpace, Buffer *buf,
1349 	 void *pattern)
1350 {
1351     if (DEBUG(VAR))
1352 	fprintf(debug_file, "VarMatch [%s] [%s]\n", word, (char *)pattern);
1353     if (Str_Match(word, (char *)pattern)) {
1354 	if (addSpace && vpstate->varSpace) {
1355 	    Buf_AddByte(buf, vpstate->varSpace);
1356 	}
1357 	addSpace = TRUE;
1358 	Buf_AddBytes(buf, strlen(word), word);
1359     }
1360     return(addSpace);
1361 }
1362 
1363 #ifdef SYSVVARSUB
1364 /*-
1365  *-----------------------------------------------------------------------
1366  * VarSYSVMatch --
1367  *	Place the word in the buffer if it matches the given pattern.
1368  *	Callback function for VarModify to implement the System V %
1369  *	modifiers.
1370  *
1371  * Input:
1372  *	word		Word to examine
1373  *	addSpace	TRUE if need to add a space to the buffer
1374  *			before adding the word, if it matches
1375  *	buf		Buffer in which to store it
1376  *	patp		Pattern the word must match
1377  *
1378  * Results:
1379  *	TRUE if a space should be placed in the buffer before the next
1380  *	word.
1381  *
1382  * Side Effects:
1383  *	The word may be copied to the buffer.
1384  *
1385  *-----------------------------------------------------------------------
1386  */
1387 static Boolean
1388 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
1389 	     char *word, Boolean addSpace, Buffer *buf,
1390 	     void *patp)
1391 {
1392     int len;
1393     char *ptr;
1394     VarPattern 	  *pat = (VarPattern *)patp;
1395     char *varexp;
1396 
1397     if (addSpace && vpstate->varSpace)
1398 	Buf_AddByte(buf, vpstate->varSpace);
1399 
1400     addSpace = TRUE;
1401 
1402     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
1403         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
1404 	Str_SYSVSubst(buf, varexp, ptr, len);
1405 	free(varexp);
1406     } else {
1407 	Buf_AddBytes(buf, strlen(word), word);
1408     }
1409 
1410     return(addSpace);
1411 }
1412 #endif
1413 
1414 
1415 /*-
1416  *-----------------------------------------------------------------------
1417  * VarNoMatch --
1418  *	Place the word in the buffer if it doesn't match the given pattern.
1419  *	Callback function for VarModify to implement the :N modifier.
1420  *
1421  * Input:
1422  *	word		Word to examine
1423  *	addSpace	TRUE if need to add a space to the buffer
1424  *			before adding the word, if it matches
1425  *	buf		Buffer in which to store it
1426  *	pattern		Pattern the word must match
1427  *
1428  * Results:
1429  *	TRUE if a space should be placed in the buffer before the next
1430  *	word.
1431  *
1432  * Side Effects:
1433  *	The word may be copied to the buffer.
1434  *
1435  *-----------------------------------------------------------------------
1436  */
1437 static Boolean
1438 VarNoMatch(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1439 	   char *word, Boolean addSpace, Buffer *buf,
1440 	   void *pattern)
1441 {
1442     if (!Str_Match(word, (char *)pattern)) {
1443 	if (addSpace && vpstate->varSpace) {
1444 	    Buf_AddByte(buf, vpstate->varSpace);
1445 	}
1446 	addSpace = TRUE;
1447 	Buf_AddBytes(buf, strlen(word), word);
1448     }
1449     return(addSpace);
1450 }
1451 
1452 
1453 /*-
1454  *-----------------------------------------------------------------------
1455  * VarSubstitute --
1456  *	Perform a string-substitution on the given word, placing the
1457  *	result in the passed buffer.
1458  *
1459  * Input:
1460  *	word		Word to modify
1461  *	addSpace	True if space should be added before
1462  *			other characters
1463  *	buf		Buffer for result
1464  *	patternp	Pattern for substitution
1465  *
1466  * Results:
1467  *	TRUE if a space is needed before more characters are added.
1468  *
1469  * Side Effects:
1470  *	None.
1471  *
1472  *-----------------------------------------------------------------------
1473  */
1474 static Boolean
1475 VarSubstitute(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1476 	      char *word, Boolean addSpace, Buffer *buf,
1477 	      void *patternp)
1478 {
1479     int  	wordLen;    /* Length of word */
1480     char 	*cp;	    /* General pointer */
1481     VarPattern	*pattern = (VarPattern *)patternp;
1482 
1483     wordLen = strlen(word);
1484     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
1485 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
1486 	/*
1487 	 * Still substituting -- break it down into simple anchored cases
1488 	 * and if none of them fits, perform the general substitution case.
1489 	 */
1490 	if ((pattern->flags & VAR_MATCH_START) &&
1491 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
1492 		/*
1493 		 * Anchored at start and beginning of word matches pattern
1494 		 */
1495 		if ((pattern->flags & VAR_MATCH_END) &&
1496 		    (wordLen == pattern->leftLen)) {
1497 			/*
1498 			 * Also anchored at end and matches to the end (word
1499 			 * is same length as pattern) add space and rhs only
1500 			 * if rhs is non-null.
1501 			 */
1502 			if (pattern->rightLen != 0) {
1503 			    if (addSpace && vpstate->varSpace) {
1504 				Buf_AddByte(buf, vpstate->varSpace);
1505 			    }
1506 			    addSpace = TRUE;
1507 			    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1508 			}
1509 			pattern->flags |= VAR_SUB_MATCHED;
1510 		} else if (pattern->flags & VAR_MATCH_END) {
1511 		    /*
1512 		     * Doesn't match to end -- copy word wholesale
1513 		     */
1514 		    goto nosub;
1515 		} else {
1516 		    /*
1517 		     * Matches at start but need to copy in trailing characters
1518 		     */
1519 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
1520 			if (addSpace && vpstate->varSpace) {
1521 			    Buf_AddByte(buf, vpstate->varSpace);
1522 			}
1523 			addSpace = TRUE;
1524 		    }
1525 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1526 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
1527 				 (word + pattern->leftLen));
1528 		    pattern->flags |= VAR_SUB_MATCHED;
1529 		}
1530 	} else if (pattern->flags & VAR_MATCH_START) {
1531 	    /*
1532 	     * Had to match at start of word and didn't -- copy whole word.
1533 	     */
1534 	    goto nosub;
1535 	} else if (pattern->flags & VAR_MATCH_END) {
1536 	    /*
1537 	     * Anchored at end, Find only place match could occur (leftLen
1538 	     * characters from the end of the word) and see if it does. Note
1539 	     * that because the $ will be left at the end of the lhs, we have
1540 	     * to use strncmp.
1541 	     */
1542 	    cp = word + (wordLen - pattern->leftLen);
1543 	    if ((cp >= word) &&
1544 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
1545 		/*
1546 		 * Match found. If we will place characters in the buffer,
1547 		 * add a space before hand as indicated by addSpace, then
1548 		 * stuff in the initial, unmatched part of the word followed
1549 		 * by the right-hand-side.
1550 		 */
1551 		if (((cp - word) + pattern->rightLen) != 0) {
1552 		    if (addSpace && vpstate->varSpace) {
1553 			Buf_AddByte(buf, vpstate->varSpace);
1554 		    }
1555 		    addSpace = TRUE;
1556 		}
1557 		Buf_AddBytes(buf, cp - word, word);
1558 		Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1559 		pattern->flags |= VAR_SUB_MATCHED;
1560 	    } else {
1561 		/*
1562 		 * Had to match at end and didn't. Copy entire word.
1563 		 */
1564 		goto nosub;
1565 	    }
1566 	} else {
1567 	    /*
1568 	     * Pattern is unanchored: search for the pattern in the word using
1569 	     * String_FindSubstring, copying unmatched portions and the
1570 	     * right-hand-side for each match found, handling non-global
1571 	     * substitutions correctly, etc. When the loop is done, any
1572 	     * remaining part of the word (word and wordLen are adjusted
1573 	     * accordingly through the loop) is copied straight into the
1574 	     * buffer.
1575 	     * addSpace is set FALSE as soon as a space is added to the
1576 	     * buffer.
1577 	     */
1578 	    Boolean done;
1579 	    int origSize;
1580 
1581 	    done = FALSE;
1582 	    origSize = Buf_Size(buf);
1583 	    while (!done) {
1584 		cp = Str_FindSubstring(word, pattern->lhs);
1585 		if (cp != NULL) {
1586 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
1587 			Buf_AddByte(buf, vpstate->varSpace);
1588 			addSpace = FALSE;
1589 		    }
1590 		    Buf_AddBytes(buf, cp-word, word);
1591 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
1592 		    wordLen -= (cp - word) + pattern->leftLen;
1593 		    word = cp + pattern->leftLen;
1594 		    if (wordLen == 0) {
1595 			done = TRUE;
1596 		    }
1597 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
1598 			done = TRUE;
1599 		    }
1600 		    pattern->flags |= VAR_SUB_MATCHED;
1601 		} else {
1602 		    done = TRUE;
1603 		}
1604 	    }
1605 	    if (wordLen != 0) {
1606 		if (addSpace && vpstate->varSpace) {
1607 		    Buf_AddByte(buf, vpstate->varSpace);
1608 		}
1609 		Buf_AddBytes(buf, wordLen, word);
1610 	    }
1611 	    /*
1612 	     * If added characters to the buffer, need to add a space
1613 	     * before we add any more. If we didn't add any, just return
1614 	     * the previous value of addSpace.
1615 	     */
1616 	    return ((Buf_Size(buf) != origSize) || addSpace);
1617 	}
1618 	return (addSpace);
1619     }
1620  nosub:
1621     if (addSpace && vpstate->varSpace) {
1622 	Buf_AddByte(buf, vpstate->varSpace);
1623     }
1624     Buf_AddBytes(buf, wordLen, word);
1625     return(TRUE);
1626 }
1627 
1628 #ifndef NO_REGEX
1629 /*-
1630  *-----------------------------------------------------------------------
1631  * VarREError --
1632  *	Print the error caused by a regcomp or regexec call.
1633  *
1634  * Results:
1635  *	None.
1636  *
1637  * Side Effects:
1638  *	An error gets printed.
1639  *
1640  *-----------------------------------------------------------------------
1641  */
1642 static void
1643 VarREError(int errnum, regex_t *pat, const char *str)
1644 {
1645     char *errbuf;
1646     int errlen;
1647 
1648     errlen = regerror(errnum, pat, 0, 0);
1649     errbuf = bmake_malloc(errlen);
1650     regerror(errnum, pat, errbuf, errlen);
1651     Error("%s: %s", str, errbuf);
1652     free(errbuf);
1653 }
1654 
1655 
1656 /*-
1657  *-----------------------------------------------------------------------
1658  * VarRESubstitute --
1659  *	Perform a regex substitution on the given word, placing the
1660  *	result in the passed buffer.
1661  *
1662  * Results:
1663  *	TRUE if a space is needed before more characters are added.
1664  *
1665  * Side Effects:
1666  *	None.
1667  *
1668  *-----------------------------------------------------------------------
1669  */
1670 static Boolean
1671 VarRESubstitute(GNode *ctx MAKE_ATTR_UNUSED,
1672 		Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
1673 		char *word, Boolean addSpace, Buffer *buf,
1674 		void *patternp)
1675 {
1676     VarREPattern *pat;
1677     int xrv;
1678     char *wp;
1679     char *rp;
1680     int added;
1681     int flags = 0;
1682 
1683 #define MAYBE_ADD_SPACE()		\
1684 	if (addSpace && !added)		\
1685 	    Buf_AddByte(buf, ' ');	\
1686 	added = 1
1687 
1688     added = 0;
1689     wp = word;
1690     pat = patternp;
1691 
1692     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1693 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1694 	xrv = REG_NOMATCH;
1695     else {
1696     tryagain:
1697 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1698     }
1699 
1700     switch (xrv) {
1701     case 0:
1702 	pat->flags |= VAR_SUB_MATCHED;
1703 	if (pat->matches[0].rm_so > 0) {
1704 	    MAYBE_ADD_SPACE();
1705 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1706 	}
1707 
1708 	for (rp = pat->replace; *rp; rp++) {
1709 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1710 		MAYBE_ADD_SPACE();
1711 		Buf_AddByte(buf,rp[1]);
1712 		rp++;
1713 	    }
1714 	    else if ((*rp == '&') ||
1715 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1716 		int n;
1717 		const char *subbuf;
1718 		int sublen;
1719 		char errstr[3];
1720 
1721 		if (*rp == '&') {
1722 		    n = 0;
1723 		    errstr[0] = '&';
1724 		    errstr[1] = '\0';
1725 		} else {
1726 		    n = rp[1] - '0';
1727 		    errstr[0] = '\\';
1728 		    errstr[1] = rp[1];
1729 		    errstr[2] = '\0';
1730 		    rp++;
1731 		}
1732 
1733 		if (n > pat->nsub) {
1734 		    Error("No subexpression %s", &errstr[0]);
1735 		    subbuf = "";
1736 		    sublen = 0;
1737 		} else if ((pat->matches[n].rm_so == -1) &&
1738 			   (pat->matches[n].rm_eo == -1)) {
1739 		    Error("No match for subexpression %s", &errstr[0]);
1740 		    subbuf = "";
1741 		    sublen = 0;
1742 	        } else {
1743 		    subbuf = wp + pat->matches[n].rm_so;
1744 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1745 		}
1746 
1747 		if (sublen > 0) {
1748 		    MAYBE_ADD_SPACE();
1749 		    Buf_AddBytes(buf, sublen, subbuf);
1750 		}
1751 	    } else {
1752 		MAYBE_ADD_SPACE();
1753 		Buf_AddByte(buf, *rp);
1754 	    }
1755 	}
1756 	wp += pat->matches[0].rm_eo;
1757 	if (pat->flags & VAR_SUB_GLOBAL) {
1758 	    flags |= REG_NOTBOL;
1759 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1760 		MAYBE_ADD_SPACE();
1761 		Buf_AddByte(buf, *wp);
1762 		wp++;
1763 
1764 	    }
1765 	    if (*wp)
1766 		goto tryagain;
1767 	}
1768 	if (*wp) {
1769 	    MAYBE_ADD_SPACE();
1770 	    Buf_AddBytes(buf, strlen(wp), wp);
1771 	}
1772 	break;
1773     default:
1774 	VarREError(xrv, &pat->re, "Unexpected regex error");
1775        /* fall through */
1776     case REG_NOMATCH:
1777 	if (*wp) {
1778 	    MAYBE_ADD_SPACE();
1779 	    Buf_AddBytes(buf,strlen(wp),wp);
1780 	}
1781 	break;
1782     }
1783     return(addSpace||added);
1784 }
1785 #endif
1786 
1787 
1788 
1789 /*-
1790  *-----------------------------------------------------------------------
1791  * VarLoopExpand --
1792  *	Implements the :@<temp>@<string>@ modifier of ODE make.
1793  *	We set the temp variable named in pattern.lhs to word and expand
1794  *	pattern.rhs storing the result in the passed buffer.
1795  *
1796  * Input:
1797  *	word		Word to modify
1798  *	addSpace	True if space should be added before
1799  *			other characters
1800  *	buf		Buffer for result
1801  *	pattern		Datafor substitution
1802  *
1803  * Results:
1804  *	TRUE if a space is needed before more characters are added.
1805  *
1806  * Side Effects:
1807  *	None.
1808  *
1809  *-----------------------------------------------------------------------
1810  */
1811 static Boolean
1812 VarLoopExpand(GNode *ctx MAKE_ATTR_UNUSED,
1813 	      Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
1814 	      char *word, Boolean addSpace, Buffer *buf,
1815 	      void *loopp)
1816 {
1817     VarLoop_t	*loop = (VarLoop_t *)loopp;
1818     char *s;
1819     int slen;
1820 
1821     if (word && *word) {
1822         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
1823         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->errnum);
1824         if (s != NULL && *s != '\0') {
1825             if (addSpace && *s != '\n')
1826                 Buf_AddByte(buf, ' ');
1827             Buf_AddBytes(buf, (slen = strlen(s)), s);
1828             addSpace = (slen > 0 && s[slen - 1] != '\n');
1829             free(s);
1830         }
1831     }
1832     return addSpace;
1833 }
1834 
1835 
1836 /*-
1837  *-----------------------------------------------------------------------
1838  * VarSelectWords --
1839  *	Implements the :[start..end] modifier.
1840  *	This is a special case of VarModify since we want to be able
1841  *	to scan the list backwards if start > end.
1842  *
1843  * Input:
1844  *	str		String whose words should be trimmed
1845  *	seldata		words to select
1846  *
1847  * Results:
1848  *	A string of all the words selected.
1849  *
1850  * Side Effects:
1851  *	None.
1852  *
1853  *-----------------------------------------------------------------------
1854  */
1855 static char *
1856 VarSelectWords(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1857 	       const char *str, VarSelectWords_t *seldata)
1858 {
1859     Buffer  	  buf;		    /* Buffer for the new string */
1860     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1861 				     * buffer before adding the trimmed
1862 				     * word */
1863     char **av;			    /* word list */
1864     char *as;			    /* word list memory */
1865     int ac, i;
1866     int start, end, step;
1867 
1868     Buf_Init(&buf, 0);
1869     addSpace = FALSE;
1870 
1871     if (vpstate->oneBigWord) {
1872 	/* fake what brk_string() would do if there were only one word */
1873 	ac = 1;
1874     	av = bmake_malloc((ac + 1) * sizeof(char *));
1875 	as = bmake_strdup(str);
1876 	av[0] = as;
1877 	av[1] = NULL;
1878     } else {
1879 	av = brk_string(str, &ac, FALSE, &as);
1880     }
1881 
1882     /*
1883      * Now sanitize seldata.
1884      * If seldata->start or seldata->end are negative, convert them to
1885      * the positive equivalents (-1 gets converted to argc, -2 gets
1886      * converted to (argc-1), etc.).
1887      */
1888     if (seldata->start < 0)
1889 	seldata->start = ac + seldata->start + 1;
1890     if (seldata->end < 0)
1891 	seldata->end = ac + seldata->end + 1;
1892 
1893     /*
1894      * We avoid scanning more of the list than we need to.
1895      */
1896     if (seldata->start > seldata->end) {
1897 	start = MIN(ac, seldata->start) - 1;
1898 	end = MAX(0, seldata->end - 1);
1899 	step = -1;
1900     } else {
1901 	start = MAX(0, seldata->start - 1);
1902 	end = MIN(ac, seldata->end);
1903 	step = 1;
1904     }
1905 
1906     for (i = start;
1907 	 (step < 0 && i >= end) || (step > 0 && i < end);
1908 	 i += step) {
1909 	if (av[i] && *av[i]) {
1910 	    if (addSpace && vpstate->varSpace) {
1911 		Buf_AddByte(&buf, vpstate->varSpace);
1912 	    }
1913 	    Buf_AddBytes(&buf, strlen(av[i]), av[i]);
1914 	    addSpace = TRUE;
1915 	}
1916     }
1917 
1918     free(as);
1919     free(av);
1920 
1921     return Buf_Destroy(&buf, FALSE);
1922 }
1923 
1924 
1925 /*-
1926  * VarRealpath --
1927  *	Replace each word with the result of realpath()
1928  *	if successful.
1929  */
1930 static Boolean
1931 VarRealpath(GNode *ctx MAKE_ATTR_UNUSED, Var_Parse_State *vpstate,
1932 	    char *word, Boolean addSpace, Buffer *buf,
1933 	    void *patternp MAKE_ATTR_UNUSED)
1934 {
1935 	struct stat st;
1936 	char rbuf[MAXPATHLEN];
1937 	char *rp;
1938 
1939 	if (addSpace && vpstate->varSpace) {
1940 	    Buf_AddByte(buf, vpstate->varSpace);
1941 	}
1942 	addSpace = TRUE;
1943 	rp = realpath(word, rbuf);
1944 	if (rp && *rp == '/' && stat(rp, &st) == 0)
1945 		word = rp;
1946 
1947 	Buf_AddBytes(buf, strlen(word), word);
1948 	return(addSpace);
1949 }
1950 
1951 /*-
1952  *-----------------------------------------------------------------------
1953  * VarModify --
1954  *	Modify each of the words of the passed string using the given
1955  *	function. Used to implement all modifiers.
1956  *
1957  * Input:
1958  *	str		String whose words should be trimmed
1959  *	modProc		Function to use to modify them
1960  *	datum		Datum to pass it
1961  *
1962  * Results:
1963  *	A string of all the words modified appropriately.
1964  *
1965  * Side Effects:
1966  *	None.
1967  *
1968  *-----------------------------------------------------------------------
1969  */
1970 static char *
1971 VarModify(GNode *ctx, Var_Parse_State *vpstate,
1972     const char *str,
1973     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
1974 		       Boolean, Buffer *, void *),
1975     void *datum)
1976 {
1977     Buffer  	  buf;		    /* Buffer for the new string */
1978     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1979 				     * buffer before adding the trimmed
1980 				     * word */
1981     char **av;			    /* word list */
1982     char *as;			    /* word list memory */
1983     int ac, i;
1984 
1985     Buf_Init(&buf, 0);
1986     addSpace = FALSE;
1987 
1988     if (vpstate->oneBigWord) {
1989 	/* fake what brk_string() would do if there were only one word */
1990 	ac = 1;
1991     	av = bmake_malloc((ac + 1) * sizeof(char *));
1992 	as = bmake_strdup(str);
1993 	av[0] = as;
1994 	av[1] = NULL;
1995     } else {
1996 	av = brk_string(str, &ac, FALSE, &as);
1997     }
1998 
1999     for (i = 0; i < ac; i++) {
2000 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, &buf, datum);
2001     }
2002 
2003     free(as);
2004     free(av);
2005 
2006     return Buf_Destroy(&buf, FALSE);
2007 }
2008 
2009 
2010 static int
2011 VarWordCompare(const void *a, const void *b)
2012 {
2013 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
2014 	return r;
2015 }
2016 
2017 /*-
2018  *-----------------------------------------------------------------------
2019  * VarOrder --
2020  *	Order the words in the string.
2021  *
2022  * Input:
2023  *	str		String whose words should be sorted.
2024  *	otype		How to order: s - sort, x - random.
2025  *
2026  * Results:
2027  *	A string containing the words ordered.
2028  *
2029  * Side Effects:
2030  *	None.
2031  *
2032  *-----------------------------------------------------------------------
2033  */
2034 static char *
2035 VarOrder(const char *str, const char otype)
2036 {
2037     Buffer  	  buf;		    /* Buffer for the new string */
2038     char **av;			    /* word list [first word does not count] */
2039     char *as;			    /* word list memory */
2040     int ac, i;
2041 
2042     Buf_Init(&buf, 0);
2043 
2044     av = brk_string(str, &ac, FALSE, &as);
2045 
2046     if (ac > 0)
2047 	switch (otype) {
2048 	case 's':	/* sort alphabetically */
2049 	    qsort(av, ac, sizeof(char *), VarWordCompare);
2050 	    break;
2051 	case 'x':	/* randomize */
2052 	{
2053 	    int rndidx;
2054 	    char *t;
2055 
2056 	    /*
2057 	     * We will use [ac..2] range for mod factors. This will produce
2058 	     * random numbers in [(ac-1)..0] interval, and minimal
2059 	     * reasonable value for mod factor is 2 (the mod 1 will produce
2060 	     * 0 with probability 1).
2061 	     */
2062 	    for (i = ac-1; i > 0; i--) {
2063 		rndidx = random() % (i + 1);
2064 		if (i != rndidx) {
2065 		    t = av[i];
2066 		    av[i] = av[rndidx];
2067 		    av[rndidx] = t;
2068 		}
2069 	    }
2070 	}
2071 	} /* end of switch */
2072 
2073     for (i = 0; i < ac; i++) {
2074 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
2075 	if (i != ac - 1)
2076 	    Buf_AddByte(&buf, ' ');
2077     }
2078 
2079     free(as);
2080     free(av);
2081 
2082     return Buf_Destroy(&buf, FALSE);
2083 }
2084 
2085 
2086 /*-
2087  *-----------------------------------------------------------------------
2088  * VarUniq --
2089  *	Remove adjacent duplicate words.
2090  *
2091  * Input:
2092  *	str		String whose words should be sorted
2093  *
2094  * Results:
2095  *	A string containing the resulting words.
2096  *
2097  * Side Effects:
2098  *	None.
2099  *
2100  *-----------------------------------------------------------------------
2101  */
2102 static char *
2103 VarUniq(const char *str)
2104 {
2105     Buffer	  buf;		    /* Buffer for new string */
2106     char 	**av;		    /* List of words to affect */
2107     char 	 *as;		    /* Word list memory */
2108     int 	  ac, i, j;
2109 
2110     Buf_Init(&buf, 0);
2111     av = brk_string(str, &ac, FALSE, &as);
2112 
2113     if (ac > 1) {
2114 	for (j = 0, i = 1; i < ac; i++)
2115 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
2116 		av[j] = av[i];
2117 	ac = j + 1;
2118     }
2119 
2120     for (i = 0; i < ac; i++) {
2121 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
2122 	if (i != ac - 1)
2123 	    Buf_AddByte(&buf, ' ');
2124     }
2125 
2126     free(as);
2127     free(av);
2128 
2129     return Buf_Destroy(&buf, FALSE);
2130 }
2131 
2132 
2133 /*-
2134  *-----------------------------------------------------------------------
2135  * VarGetPattern --
2136  *	Pass through the tstr looking for 1) escaped delimiters,
2137  *	'$'s and backslashes (place the escaped character in
2138  *	uninterpreted) and 2) unescaped $'s that aren't before
2139  *	the delimiter (expand the variable substitution unless flags
2140  *	has VAR_NOSUBST set).
2141  *	Return the expanded string or NULL if the delimiter was missing
2142  *	If pattern is specified, handle escaped ampersands, and replace
2143  *	unescaped ampersands with the lhs of the pattern.
2144  *
2145  * Results:
2146  *	A string of all the words modified appropriately.
2147  *	If length is specified, return the string length of the buffer
2148  *	If flags is specified and the last character of the pattern is a
2149  *	$ set the VAR_MATCH_END bit of flags.
2150  *
2151  * Side Effects:
2152  *	None.
2153  *-----------------------------------------------------------------------
2154  */
2155 static char *
2156 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate MAKE_ATTR_UNUSED,
2157 	      int errnum, const char **tstr, int delim, int *flags,
2158 	      int *length, VarPattern *pattern)
2159 {
2160     const char *cp;
2161     char *rstr;
2162     Buffer buf;
2163     int junk;
2164 
2165     Buf_Init(&buf, 0);
2166     if (length == NULL)
2167 	length = &junk;
2168 
2169 #define IS_A_MATCH(cp, delim) \
2170     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
2171      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
2172 
2173     /*
2174      * Skim through until the matching delimiter is found;
2175      * pick up variable substitutions on the way. Also allow
2176      * backslashes to quote the delimiter, $, and \, but don't
2177      * touch other backslashes.
2178      */
2179     for (cp = *tstr; *cp && (*cp != delim); cp++) {
2180 	if (IS_A_MATCH(cp, delim)) {
2181 	    Buf_AddByte(&buf, cp[1]);
2182 	    cp++;
2183 	} else if (*cp == '$') {
2184 	    if (cp[1] == delim) {
2185 		if (flags == NULL)
2186 		    Buf_AddByte(&buf, *cp);
2187 		else
2188 		    /*
2189 		     * Unescaped $ at end of pattern => anchor
2190 		     * pattern at end.
2191 		     */
2192 		    *flags |= VAR_MATCH_END;
2193 	    } else {
2194 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
2195 		    char   *cp2;
2196 		    int     len;
2197 		    void   *freeIt;
2198 
2199 		    /*
2200 		     * If unescaped dollar sign not before the
2201 		     * delimiter, assume it's a variable
2202 		     * substitution and recurse.
2203 		     */
2204 		    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
2205 		    Buf_AddBytes(&buf, strlen(cp2), cp2);
2206 		    if (freeIt)
2207 			free(freeIt);
2208 		    cp += len - 1;
2209 		} else {
2210 		    const char *cp2 = &cp[1];
2211 
2212 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
2213 			/*
2214 			 * Find the end of this variable reference
2215 			 * and suck it in without further ado.
2216 			 * It will be interperated later.
2217 			 */
2218 			int have = *cp2;
2219 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
2220 			int depth = 1;
2221 
2222 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
2223 			    if (cp2[-1] != '\\') {
2224 				if (*cp2 == have)
2225 				    ++depth;
2226 				if (*cp2 == want)
2227 				    --depth;
2228 			    }
2229 			}
2230 			Buf_AddBytes(&buf, cp2 - cp, cp);
2231 			cp = --cp2;
2232 		    } else
2233 			Buf_AddByte(&buf, *cp);
2234 		}
2235 	    }
2236 	}
2237 	else if (pattern && *cp == '&')
2238 	    Buf_AddBytes(&buf, pattern->leftLen, pattern->lhs);
2239 	else
2240 	    Buf_AddByte(&buf, *cp);
2241     }
2242 
2243     if (*cp != delim) {
2244 	*tstr = cp;
2245 	*length = 0;
2246 	return NULL;
2247     }
2248 
2249     *tstr = ++cp;
2250     *length = Buf_Size(&buf);
2251     rstr = Buf_Destroy(&buf, FALSE);
2252     if (DEBUG(VAR))
2253 	fprintf(debug_file, "Modifier pattern: \"%s\"\n", rstr);
2254     return rstr;
2255 }
2256 
2257 /*-
2258  *-----------------------------------------------------------------------
2259  * VarQuote --
2260  *	Quote shell meta-characters in the string
2261  *
2262  * Results:
2263  *	The quoted string
2264  *
2265  * Side Effects:
2266  *	None.
2267  *
2268  *-----------------------------------------------------------------------
2269  */
2270 static char *
2271 VarQuote(char *str)
2272 {
2273 
2274     Buffer  	  buf;
2275     /* This should cover most shells :-( */
2276     static const char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
2277     const char	*newline;
2278     size_t len, nlen;
2279 
2280     if ((newline = Shell_GetNewline()) == NULL)
2281 	    newline = "\\\n";
2282     nlen = strlen(newline);
2283 
2284     Buf_Init(&buf, 0);
2285     while (*str != '\0') {
2286 	if ((len = strcspn(str, meta)) != 0) {
2287 	    Buf_AddBytes(&buf, len, str);
2288 	    str += len;
2289 	} else if (*str == '\n') {
2290 	    Buf_AddBytes(&buf, nlen, newline);
2291 	    ++str;
2292 	} else {
2293 	    Buf_AddByte(&buf, '\\');
2294 	    Buf_AddByte(&buf, *str);
2295 	    ++str;
2296 	}
2297     }
2298     str = Buf_Destroy(&buf, FALSE);
2299     if (DEBUG(VAR))
2300 	fprintf(debug_file, "QuoteMeta: [%s]\n", str);
2301     return str;
2302 }
2303 
2304 /*-
2305  *-----------------------------------------------------------------------
2306  * VarHash --
2307  *      Hash the string using the MurmurHash3 algorithm.
2308  *      Output is computed using 32bit Little Endian arithmetic.
2309  *
2310  * Input:
2311  *	str		String to modify
2312  *
2313  * Results:
2314  *      Hash value of str, encoded as 8 hex digits.
2315  *
2316  * Side Effects:
2317  *      None.
2318  *
2319  *-----------------------------------------------------------------------
2320  */
2321 static char *
2322 VarHash(char *str)
2323 {
2324     static const char    hexdigits[16] = "0123456789abcdef";
2325     Buffer         buf;
2326     size_t         len, len2;
2327     unsigned char  *ustr = (unsigned char *)str;
2328     uint32_t       h, k, c1, c2;
2329     int            done;
2330 
2331     done = 1;
2332     h  = 0x971e137bU;
2333     c1 = 0x95543787U;
2334     c2 = 0x2ad7eb25U;
2335     len2 = strlen(str);
2336 
2337     for (len = len2; len; ) {
2338 	k = 0;
2339 	switch (len) {
2340 	default:
2341 	    k = (ustr[3] << 24) | (ustr[2] << 16) | (ustr[1] << 8) | ustr[0];
2342 	    len -= 4;
2343 	    ustr += 4;
2344 	    break;
2345 	case 3:
2346 	    k |= (ustr[2] << 16);
2347 	case 2:
2348 	    k |= (ustr[1] << 8);
2349 	case 1:
2350 	    k |= ustr[0];
2351 	    len = 0;
2352 	}
2353 	c1 = c1 * 5 + 0x7b7d159cU;
2354 	c2 = c2 * 5 + 0x6bce6396U;
2355 	k *= c1;
2356 	k = (k << 11) ^ (k >> 21);
2357 	k *= c2;
2358 	h = (h << 13) ^ (h >> 19);
2359 	h = h * 5 + 0x52dce729U;
2360 	h ^= k;
2361    } while (!done);
2362    h ^= len2;
2363    h *= 0x85ebca6b;
2364    h ^= h >> 13;
2365    h *= 0xc2b2ae35;
2366    h ^= h >> 16;
2367 
2368    Buf_Init(&buf, 0);
2369    for (len = 0; len < 8; ++len) {
2370        Buf_AddByte(&buf, hexdigits[h & 15]);
2371        h >>= 4;
2372    }
2373 
2374    return Buf_Destroy(&buf, FALSE);
2375 }
2376 
2377 static char *
2378 VarStrftime(const char *fmt, int zulu)
2379 {
2380     char buf[BUFSIZ];
2381     time_t utc;
2382 
2383     time(&utc);
2384     if (!*fmt)
2385 	fmt = "%c";
2386     strftime(buf, sizeof(buf), fmt, zulu ? gmtime(&utc) : localtime(&utc));
2387 
2388     buf[sizeof(buf) - 1] = '\0';
2389     return bmake_strdup(buf);
2390 }
2391 
2392 /*
2393  * Now we need to apply any modifiers the user wants applied.
2394  * These are:
2395  *  	  :M<pattern>	words which match the given <pattern>.
2396  *  			<pattern> is of the standard file
2397  *  			wildcarding form.
2398  *  	  :N<pattern>	words which do not match the given <pattern>.
2399  *  	  :S<d><pat1><d><pat2><d>[1gW]
2400  *  			Substitute <pat2> for <pat1> in the value
2401  *  	  :C<d><pat1><d><pat2><d>[1gW]
2402  *  			Substitute <pat2> for regex <pat1> in the value
2403  *  	  :H		Substitute the head of each word
2404  *  	  :T		Substitute the tail of each word
2405  *  	  :E		Substitute the extension (minus '.') of
2406  *  			each word
2407  *  	  :R		Substitute the root of each word
2408  *  			(pathname minus the suffix).
2409  *	  :O		("Order") Alphabeticaly sort words in variable.
2410  *	  :Ox		("intermiX") Randomize words in variable.
2411  *	  :u		("uniq") Remove adjacent duplicate words.
2412  *	  :tu		Converts the variable contents to uppercase.
2413  *	  :tl		Converts the variable contents to lowercase.
2414  *	  :ts[c]	Sets varSpace - the char used to
2415  *			separate words to 'c'. If 'c' is
2416  *			omitted then no separation is used.
2417  *	  :tW		Treat the variable contents as a single
2418  *			word, even if it contains spaces.
2419  *			(Mnemonic: one big 'W'ord.)
2420  *	  :tw		Treat the variable contents as multiple
2421  *			space-separated words.
2422  *			(Mnemonic: many small 'w'ords.)
2423  *	  :[index]	Select a single word from the value.
2424  *	  :[start..end]	Select multiple words from the value.
2425  *	  :[*] or :[0]	Select the entire value, as a single
2426  *			word.  Equivalent to :tW.
2427  *	  :[@]		Select the entire value, as multiple
2428  *			words.	Undoes the effect of :[*].
2429  *			Equivalent to :tw.
2430  *	  :[#]		Returns the number of words in the value.
2431  *
2432  *	  :?<true-value>:<false-value>
2433  *			If the variable evaluates to true, return
2434  *			true value, else return the second value.
2435  *    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
2436  *    			the invocation.
2437  *	  :sh		Treat the current value as a command
2438  *			to be run, new value is its output.
2439  * The following added so we can handle ODE makefiles.
2440  *	  :@<tmpvar>@<newval>@
2441  *			Assign a temporary local variable <tmpvar>
2442  *			to the current value of each word in turn
2443  *			and replace each word with the result of
2444  *			evaluating <newval>
2445  *	  :D<newval>	Use <newval> as value if variable defined
2446  *	  :U<newval>	Use <newval> as value if variable undefined
2447  *	  :L		Use the name of the variable as the value.
2448  *	  :P		Use the path of the node that has the same
2449  *			name as the variable as the value.  This
2450  *			basically includes an implied :L so that
2451  *			the common method of refering to the path
2452  *			of your dependent 'x' in a rule is to use
2453  *			the form '${x:P}'.
2454  *	  :!<cmd>!	Run cmd much the same as :sh run's the
2455  *			current value of the variable.
2456  * The ::= modifiers, actually assign a value to the variable.
2457  * Their main purpose is in supporting modifiers of .for loop
2458  * iterators and other obscure uses.  They always expand to
2459  * nothing.  In a target rule that would otherwise expand to an
2460  * empty line they can be preceded with @: to keep make happy.
2461  * Eg.
2462  *
2463  * foo:	.USE
2464  * .for i in ${.TARGET} ${.TARGET:R}.gz
2465  * 	@: ${t::=$i}
2466  *	@echo blah ${t:T}
2467  * .endfor
2468  *
2469  *	  ::=<str>	Assigns <str> as the new value of variable.
2470  *	  ::?=<str>	Assigns <str> as value of variable if
2471  *			it was not already set.
2472  *	  ::+=<str>	Appends <str> to variable.
2473  *	  ::!=<cmd>	Assigns output of <cmd> as the new value of
2474  *			variable.
2475  */
2476 
2477 /* we now have some modifiers with long names */
2478 #define STRMOD_MATCH(s, want, n) \
2479     (strncmp(s, want, n) == 0 && (s[n] == endc || s[n] == ':'))
2480 
2481 static char *
2482 ApplyModifiers(char *nstr, const char *tstr,
2483 	       int startc, int endc,
2484 	       Var *v, GNode *ctxt, Boolean errnum,
2485 	       int *lengthPtr, void **freePtr)
2486 {
2487     const char 	   *start;
2488     const char     *cp;    	/* Secondary pointer into str (place marker
2489 				 * for tstr) */
2490     char	   *newStr;	/* New value to return */
2491     char	    termc;	/* Character which terminated scan */
2492     int             cnt;	/* Used to count brace pairs when variable in
2493 				 * in parens or braces */
2494     char	delim;
2495     int		modifier;	/* that we are processing */
2496     Var_Parse_State parsestate; /* Flags passed to helper functions */
2497 
2498     delim = '\0';
2499     parsestate.oneBigWord = FALSE;
2500     parsestate.varSpace = ' ';	/* word separator */
2501 
2502     start = cp = tstr;
2503 
2504     while (*tstr && *tstr != endc) {
2505 
2506 	if (*tstr == '$') {
2507 	    /*
2508 	     * We may have some complex modifiers in a variable.
2509 	     */
2510 	    void *freeIt;
2511 	    char *rval;
2512 	    int rlen;
2513 	    int c;
2514 
2515 	    rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
2516 
2517 	    /*
2518 	     * If we have not parsed up to endc or ':',
2519 	     * we are not interested.
2520 	     */
2521 	    if (rval != NULL && *rval &&
2522 		(c = tstr[rlen]) != '\0' &&
2523 		c != ':' &&
2524 		c != endc) {
2525 		if (freeIt)
2526 		    free(freeIt);
2527 		goto apply_mods;
2528 	    }
2529 
2530 	    if (DEBUG(VAR)) {
2531 		fprintf(debug_file, "Got '%s' from '%.*s'%.*s\n",
2532 		       rval, rlen, tstr, rlen, tstr + rlen);
2533 	    }
2534 
2535 	    tstr += rlen;
2536 
2537 	    if (rval != NULL && *rval) {
2538 		int used;
2539 
2540 		nstr = ApplyModifiers(nstr, rval,
2541 				      0, 0,
2542 				      v, ctxt, errnum, &used, freePtr);
2543 		if (nstr == var_Error
2544 		    || (nstr == varNoError && errnum == 0)
2545 		    || strlen(rval) != (size_t) used) {
2546 		    if (freeIt)
2547 			free(freeIt);
2548 		    goto out;		/* error already reported */
2549 		}
2550 	    }
2551 	    if (freeIt)
2552 		free(freeIt);
2553 	    if (*tstr == ':')
2554 		tstr++;
2555 	    else if (!*tstr && endc) {
2556 		Error("Unclosed variable specification after complex modifier (expecting '%c') for %s", endc, v->name);
2557 		goto out;
2558 	    }
2559 	    continue;
2560 	}
2561     apply_mods:
2562 	if (DEBUG(VAR)) {
2563 	    fprintf(debug_file, "Applying[%s] :%c to \"%s\"\n", v->name,
2564 		*tstr, nstr);
2565 	}
2566 	newStr = var_Error;
2567 	switch ((modifier = *tstr)) {
2568 	case ':':
2569 	    {
2570 		if (tstr[1] == '=' ||
2571 		    (tstr[2] == '=' &&
2572 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
2573 		    /*
2574 		     * "::=", "::!=", "::+=", or "::?="
2575 		     */
2576 		    GNode *v_ctxt;		/* context where v belongs */
2577 		    const char *emsg;
2578 		    char *sv_name;
2579 		    VarPattern	pattern;
2580 		    int	how;
2581 
2582 		    if (v->name[0] == 0)
2583 			goto bad_modifier;
2584 
2585 		    v_ctxt = ctxt;
2586 		    sv_name = NULL;
2587 		    ++tstr;
2588 		    if (v->flags & VAR_JUNK) {
2589 			/*
2590 			 * We need to bmake_strdup() it incase
2591 			 * VarGetPattern() recurses.
2592 			 */
2593 			sv_name = v->name;
2594 			v->name = bmake_strdup(v->name);
2595 		    } else if (ctxt != VAR_GLOBAL) {
2596 			Var *gv = VarFind(v->name, ctxt, 0);
2597 			if (gv == NULL)
2598 			    v_ctxt = VAR_GLOBAL;
2599 			else
2600 			    VarFreeEnv(gv, TRUE);
2601 		    }
2602 
2603 		    switch ((how = *tstr)) {
2604 		    case '+':
2605 		    case '?':
2606 		    case '!':
2607 			cp = &tstr[2];
2608 			break;
2609 		    default:
2610 			cp = ++tstr;
2611 			break;
2612 		    }
2613 		    delim = startc == PROPEN ? PRCLOSE : BRCLOSE;
2614 		    pattern.flags = 0;
2615 
2616 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2617 						&cp, delim, NULL,
2618 						&pattern.rightLen,
2619 						NULL);
2620 		    if (v->flags & VAR_JUNK) {
2621 			/* restore original name */
2622 			free(v->name);
2623 			v->name = sv_name;
2624 		    }
2625 		    if (pattern.rhs == NULL)
2626 			goto cleanup;
2627 
2628 		    termc = *--cp;
2629 		    delim = '\0';
2630 
2631 		    switch (how) {
2632 		    case '+':
2633 			Var_Append(v->name, pattern.rhs, v_ctxt);
2634 			break;
2635 		    case '!':
2636 			newStr = Cmd_Exec(pattern.rhs, &emsg);
2637 			if (emsg)
2638 			    Error(emsg, nstr);
2639 			else
2640 			    Var_Set(v->name, newStr,  v_ctxt, 0);
2641 			if (newStr)
2642 			    free(newStr);
2643 			break;
2644 		    case '?':
2645 			if ((v->flags & VAR_JUNK) == 0)
2646 			    break;
2647 			/* FALLTHROUGH */
2648 		    default:
2649 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
2650 			break;
2651 		    }
2652 		    free(UNCONST(pattern.rhs));
2653 		    newStr = var_Error;
2654 		    break;
2655 		}
2656 		goto default_case; /* "::<unrecognised>" */
2657 	    }
2658 	case '@':
2659 	    {
2660 		VarLoop_t	loop;
2661 		int flags = VAR_NOSUBST;
2662 
2663 		cp = ++tstr;
2664 		delim = '@';
2665 		if ((loop.tvar = VarGetPattern(ctxt, &parsestate, errnum,
2666 					       &cp, delim,
2667 					       &flags, &loop.tvarLen,
2668 					       NULL)) == NULL)
2669 		    goto cleanup;
2670 
2671 		if ((loop.str = VarGetPattern(ctxt, &parsestate, errnum,
2672 					      &cp, delim,
2673 					      &flags, &loop.strLen,
2674 					      NULL)) == NULL)
2675 		    goto cleanup;
2676 
2677 		termc = *cp;
2678 		delim = '\0';
2679 
2680 		loop.errnum = errnum;
2681 		loop.ctxt = ctxt;
2682 		newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
2683 				   &loop);
2684 		free(loop.tvar);
2685 		free(loop.str);
2686 		break;
2687 	    }
2688 	case 'U':
2689 #ifdef MAKE_FREEBSD_UL
2690 	    if (FreeBSD_UL) {
2691 		int nc = tstr[1];
2692 
2693 		/* we have to be careful, since :U is used internally */
2694 		if (nc == ':' || nc == endc) {
2695 		    char *dp = bmake_strdup(nstr);
2696 		    for (newStr = dp; *dp; dp++)
2697 			*dp = toupper((unsigned char)*dp);
2698 		    cp = tstr + 1;
2699 		    termc = *cp;
2700 		    break;		/* yes inside the conditional */
2701 		}
2702 		/* FALLTHROUGH */
2703 	    }
2704 #endif
2705 	case 'D':
2706 	    {
2707 		Buffer  buf;    	/* Buffer for patterns */
2708 		int	    wantit;	/* want data in buffer */
2709 
2710 		/*
2711 		 * Pass through tstr looking for 1) escaped delimiters,
2712 		 * '$'s and backslashes (place the escaped character in
2713 		 * uninterpreted) and 2) unescaped $'s that aren't before
2714 		 * the delimiter (expand the variable substitution).
2715 		 * The result is left in the Buffer buf.
2716 		 */
2717 		Buf_Init(&buf, 0);
2718 		for (cp = tstr + 1;
2719 		     *cp != endc && *cp != ':' && *cp != '\0';
2720 		     cp++) {
2721 		    if ((*cp == '\\') &&
2722 			((cp[1] == ':') ||
2723 			 (cp[1] == '$') ||
2724 			 (cp[1] == endc) ||
2725 			 (cp[1] == '\\')))
2726 			{
2727 			    Buf_AddByte(&buf, cp[1]);
2728 			    cp++;
2729 			} else if (*cp == '$') {
2730 			    /*
2731 			     * If unescaped dollar sign, assume it's a
2732 			     * variable substitution and recurse.
2733 			     */
2734 			    char    *cp2;
2735 			    int	    len;
2736 			    void    *freeIt;
2737 
2738 			    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
2739 			    Buf_AddBytes(&buf, strlen(cp2), cp2);
2740 			    if (freeIt)
2741 				free(freeIt);
2742 			    cp += len - 1;
2743 			} else {
2744 			    Buf_AddByte(&buf, *cp);
2745 			}
2746 		}
2747 
2748 		termc = *cp;
2749 
2750 		if (*tstr == 'U')
2751 		    wantit = ((v->flags & VAR_JUNK) != 0);
2752 		else
2753 		    wantit = ((v->flags & VAR_JUNK) == 0);
2754 		if ((v->flags & VAR_JUNK) != 0)
2755 		    v->flags |= VAR_KEEP;
2756 		if (wantit) {
2757 		    newStr = Buf_Destroy(&buf, FALSE);
2758 		} else {
2759 		    newStr = nstr;
2760 		    Buf_Destroy(&buf, TRUE);
2761 		}
2762 		break;
2763 	    }
2764 	case 'L':
2765 #ifdef MAKE_FREEBSD_UL
2766 	    if (FreeBSD_UL) {
2767 		char *dp = bmake_strdup(nstr);
2768 		for (newStr = dp; *dp; dp++)
2769 		    *dp = tolower((unsigned char)*dp);
2770 		cp = tstr + 1;
2771 		termc = *cp;
2772 		break;
2773 	    }
2774 	    /* FALLTHROUGH */
2775 #endif
2776 	    {
2777 		if ((v->flags & VAR_JUNK) != 0)
2778 		    v->flags |= VAR_KEEP;
2779 		newStr = bmake_strdup(v->name);
2780 		cp = ++tstr;
2781 		termc = *tstr;
2782 		break;
2783 	    }
2784 	case 'P':
2785 	    {
2786 		GNode *gn;
2787 
2788 		if ((v->flags & VAR_JUNK) != 0)
2789 		    v->flags |= VAR_KEEP;
2790 		gn = Targ_FindNode(v->name, TARG_NOCREATE);
2791 		if (gn == NULL || gn->type & OP_NOPATH) {
2792 		    newStr = NULL;
2793 		} else if (gn->path) {
2794 		    newStr = bmake_strdup(gn->path);
2795 		} else {
2796 		    newStr = Dir_FindFile(v->name, Suff_FindPath(gn));
2797 		}
2798 		if (!newStr) {
2799 		    newStr = bmake_strdup(v->name);
2800 		}
2801 		cp = ++tstr;
2802 		termc = *tstr;
2803 		break;
2804 	    }
2805 	case '!':
2806 	    {
2807 		const char *emsg;
2808 		VarPattern 	    pattern;
2809 		pattern.flags = 0;
2810 
2811 		delim = '!';
2812 
2813 		cp = ++tstr;
2814 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2815 						 &cp, delim,
2816 						 NULL, &pattern.rightLen,
2817 						 NULL)) == NULL)
2818 		    goto cleanup;
2819 		newStr = Cmd_Exec(pattern.rhs, &emsg);
2820 		free(UNCONST(pattern.rhs));
2821 		if (emsg)
2822 		    Error(emsg, nstr);
2823 		termc = *cp;
2824 		delim = '\0';
2825 		if (v->flags & VAR_JUNK) {
2826 		    v->flags |= VAR_KEEP;
2827 		}
2828 		break;
2829 	    }
2830 	case '[':
2831 	    {
2832 		/*
2833 		 * Look for the closing ']', recursively
2834 		 * expanding any embedded variables.
2835 		 *
2836 		 * estr is a pointer to the expanded result,
2837 		 * which we must free().
2838 		 */
2839 		char *estr;
2840 
2841 		cp = tstr+1; /* point to char after '[' */
2842 		delim = ']'; /* look for closing ']' */
2843 		estr = VarGetPattern(ctxt, &parsestate,
2844 				     errnum, &cp, delim,
2845 				     NULL, NULL, NULL);
2846 		if (estr == NULL)
2847 		    goto cleanup; /* report missing ']' */
2848 		/* now cp points just after the closing ']' */
2849 		delim = '\0';
2850 		if (cp[0] != ':' && cp[0] != endc) {
2851 		    /* Found junk after ']' */
2852 		    free(estr);
2853 		    goto bad_modifier;
2854 		}
2855 		if (estr[0] == '\0') {
2856 		    /* Found empty square brackets in ":[]". */
2857 		    free(estr);
2858 		    goto bad_modifier;
2859 		} else if (estr[0] == '#' && estr[1] == '\0') {
2860 		    /* Found ":[#]" */
2861 
2862 		    /*
2863 		     * We will need enough space for the decimal
2864 		     * representation of an int.  We calculate the
2865 		     * space needed for the octal representation,
2866 		     * and add enough slop to cope with a '-' sign
2867 		     * (which should never be needed) and a '\0'
2868 		     * string terminator.
2869 		     */
2870 		    int newStrSize =
2871 			(sizeof(int) * CHAR_BIT + 2) / 3 + 2;
2872 
2873 		    newStr = bmake_malloc(newStrSize);
2874 		    if (parsestate.oneBigWord) {
2875 			strncpy(newStr, "1", newStrSize);
2876 		    } else {
2877 			/* XXX: brk_string() is a rather expensive
2878 			 * way of counting words. */
2879 			char **av;
2880 			char *as;
2881 			int ac;
2882 
2883 			av = brk_string(nstr, &ac, FALSE, &as);
2884 			snprintf(newStr, newStrSize,  "%d", ac);
2885 			free(as);
2886 			free(av);
2887 		    }
2888 		    termc = *cp;
2889 		    free(estr);
2890 		    break;
2891 		} else if (estr[0] == '*' && estr[1] == '\0') {
2892 		    /* Found ":[*]" */
2893 		    parsestate.oneBigWord = TRUE;
2894 		    newStr = nstr;
2895 		    termc = *cp;
2896 		    free(estr);
2897 		    break;
2898 		} else if (estr[0] == '@' && estr[1] == '\0') {
2899 		    /* Found ":[@]" */
2900 		    parsestate.oneBigWord = FALSE;
2901 		    newStr = nstr;
2902 		    termc = *cp;
2903 		    free(estr);
2904 		    break;
2905 		} else {
2906 		    /*
2907 		     * We expect estr to contain a single
2908 		     * integer for :[N], or two integers
2909 		     * separated by ".." for :[start..end].
2910 		     */
2911 		    char *ep;
2912 
2913 		    VarSelectWords_t seldata = { 0, 0 };
2914 
2915 		    seldata.start = strtol(estr, &ep, 0);
2916 		    if (ep == estr) {
2917 			/* Found junk instead of a number */
2918 			free(estr);
2919 			goto bad_modifier;
2920 		    } else if (ep[0] == '\0') {
2921 			/* Found only one integer in :[N] */
2922 			seldata.end = seldata.start;
2923 		    } else if (ep[0] == '.' && ep[1] == '.' &&
2924 			       ep[2] != '\0') {
2925 			/* Expecting another integer after ".." */
2926 			ep += 2;
2927 			seldata.end = strtol(ep, &ep, 0);
2928 			if (ep[0] != '\0') {
2929 			    /* Found junk after ".." */
2930 			    free(estr);
2931 			    goto bad_modifier;
2932 			}
2933 		    } else {
2934 			/* Found junk instead of ".." */
2935 			free(estr);
2936 			goto bad_modifier;
2937 		    }
2938 		    /*
2939 		     * Now seldata is properly filled in,
2940 		     * but we still have to check for 0 as
2941 		     * a special case.
2942 		     */
2943 		    if (seldata.start == 0 && seldata.end == 0) {
2944 			/* ":[0]" or perhaps ":[0..0]" */
2945 			parsestate.oneBigWord = TRUE;
2946 			newStr = nstr;
2947 			termc = *cp;
2948 			free(estr);
2949 			break;
2950 		    } else if (seldata.start == 0 ||
2951 			       seldata.end == 0) {
2952 			/* ":[0..N]" or ":[N..0]" */
2953 			free(estr);
2954 			goto bad_modifier;
2955 		    }
2956 		    /*
2957 		     * Normal case: select the words
2958 		     * described by seldata.
2959 		     */
2960 		    newStr = VarSelectWords(ctxt, &parsestate,
2961 					    nstr, &seldata);
2962 
2963 		    termc = *cp;
2964 		    free(estr);
2965 		    break;
2966 		}
2967 
2968 	    }
2969 	case 'g':
2970 	    cp = tstr + 1;	/* make sure it is set */
2971 	    if (STRMOD_MATCH(tstr, "gmtime", 6)) {
2972 		newStr = VarStrftime(nstr, 1);
2973 		cp = tstr + 6;
2974 		termc = *cp;
2975 	    } else {
2976 		goto default_case;
2977 	    }
2978 	    break;
2979 	case 'h':
2980 	    cp = tstr + 1;	/* make sure it is set */
2981 	    if (STRMOD_MATCH(tstr, "hash", 4)) {
2982 		newStr = VarHash(nstr);
2983 		cp = tstr + 4;
2984 		termc = *cp;
2985 	    } else {
2986 		goto default_case;
2987 	    }
2988 	    break;
2989 	case 'l':
2990 	    cp = tstr + 1;	/* make sure it is set */
2991 	    if (STRMOD_MATCH(tstr, "localtime", 9)) {
2992 		newStr = VarStrftime(nstr, 0);
2993 		cp = tstr + 9;
2994 		termc = *cp;
2995 	    } else {
2996 		goto default_case;
2997 	    }
2998 	    break;
2999 	case 't':
3000 	    {
3001 		cp = tstr + 1;	/* make sure it is set */
3002 		if (tstr[1] != endc && tstr[1] != ':') {
3003 		    if (tstr[1] == 's') {
3004 			/*
3005 			 * Use the char (if any) at tstr[2]
3006 			 * as the word separator.
3007 			 */
3008 			VarPattern pattern;
3009 
3010 			if (tstr[2] != endc &&
3011 			    (tstr[3] == endc || tstr[3] == ':')) {
3012 			    /* ":ts<unrecognised><endc>" or
3013 			     * ":ts<unrecognised>:" */
3014 			    parsestate.varSpace = tstr[2];
3015 			    cp = tstr + 3;
3016 			} else if (tstr[2] == endc || tstr[2] == ':') {
3017 			    /* ":ts<endc>" or ":ts:" */
3018 			    parsestate.varSpace = 0; /* no separator */
3019 			    cp = tstr + 2;
3020 			} else if (tstr[2] == '\\') {
3021 			    switch (tstr[3]) {
3022 			    case 'n':
3023 				parsestate.varSpace = '\n';
3024 				cp = tstr + 4;
3025 				break;
3026 			    case 't':
3027 				parsestate.varSpace = '\t';
3028 				cp = tstr + 4;
3029 				break;
3030 			    default:
3031 				if (isdigit((unsigned char)tstr[3])) {
3032 				    char *ep;
3033 
3034 				    parsestate.varSpace =
3035 					strtoul(&tstr[3], &ep, 0);
3036 				    if (*ep != ':' && *ep != endc)
3037 					goto bad_modifier;
3038 				    cp = ep;
3039 				} else {
3040 				    /*
3041 				     * ":ts<backslash><unrecognised>".
3042 				     */
3043 				    goto bad_modifier;
3044 				}
3045 				break;
3046 			    }
3047 			} else {
3048 			    /*
3049 			     * Found ":ts<unrecognised><unrecognised>".
3050 			     */
3051 			    goto bad_modifier;
3052 			}
3053 
3054 			termc = *cp;
3055 
3056 			/*
3057 			 * We cannot be certain that VarModify
3058 			 * will be used - even if there is a
3059 			 * subsequent modifier, so do a no-op
3060 			 * VarSubstitute now to for str to be
3061 			 * re-expanded without the spaces.
3062 			 */
3063 			pattern.flags = VAR_SUB_ONE;
3064 			pattern.lhs = pattern.rhs = "\032";
3065 			pattern.leftLen = pattern.rightLen = 1;
3066 
3067 			newStr = VarModify(ctxt, &parsestate, nstr,
3068 					   VarSubstitute,
3069 					   &pattern);
3070 		    } else if (tstr[2] == endc || tstr[2] == ':') {
3071 			/*
3072 			 * Check for two-character options:
3073 			 * ":tu", ":tl"
3074 			 */
3075 			if (tstr[1] == 'A') { /* absolute path */
3076 			    newStr = VarModify(ctxt, &parsestate, nstr,
3077 					       VarRealpath, NULL);
3078 			    cp = tstr + 2;
3079 			    termc = *cp;
3080 			} else if (tstr[1] == 'u') {
3081 			    char *dp = bmake_strdup(nstr);
3082 			    for (newStr = dp; *dp; dp++)
3083 				*dp = toupper((unsigned char)*dp);
3084 			    cp = tstr + 2;
3085 			    termc = *cp;
3086 			} else if (tstr[1] == 'l') {
3087 			    char *dp = bmake_strdup(nstr);
3088 			    for (newStr = dp; *dp; dp++)
3089 				*dp = tolower((unsigned char)*dp);
3090 			    cp = tstr + 2;
3091 			    termc = *cp;
3092 			} else if (tstr[1] == 'W' || tstr[1] == 'w') {
3093 			    parsestate.oneBigWord = (tstr[1] == 'W');
3094 			    newStr = nstr;
3095 			    cp = tstr + 2;
3096 			    termc = *cp;
3097 			} else {
3098 			    /* Found ":t<unrecognised>:" or
3099 			     * ":t<unrecognised><endc>". */
3100 			    goto bad_modifier;
3101 			}
3102 		    } else {
3103 			/*
3104 			 * Found ":t<unrecognised><unrecognised>".
3105 			 */
3106 			goto bad_modifier;
3107 		    }
3108 		} else {
3109 		    /*
3110 		     * Found ":t<endc>" or ":t:".
3111 		     */
3112 		    goto bad_modifier;
3113 		}
3114 		break;
3115 	    }
3116 	case 'N':
3117 	case 'M':
3118 	    {
3119 		char    *pattern;
3120 		const char *endpat; /* points just after end of pattern */
3121 		char    *cp2;
3122 		Boolean copy;	/* pattern should be, or has been, copied */
3123 		Boolean needSubst;
3124 		int nest;
3125 
3126 		copy = FALSE;
3127 		needSubst = FALSE;
3128 		nest = 1;
3129 		/*
3130 		 * In the loop below, ignore ':' unless we are at
3131 		 * (or back to) the original brace level.
3132 		 * XXX This will likely not work right if $() and ${}
3133 		 * are intermixed.
3134 		 */
3135 		for (cp = tstr + 1;
3136 		     *cp != '\0' && !(*cp == ':' && nest == 1);
3137 		     cp++)
3138 		    {
3139 			if (*cp == '\\' &&
3140 			    (cp[1] == ':' ||
3141 			     cp[1] == endc || cp[1] == startc)) {
3142 			    if (!needSubst) {
3143 				copy = TRUE;
3144 			    }
3145 			    cp++;
3146 			    continue;
3147 			}
3148 			if (*cp == '$') {
3149 			    needSubst = TRUE;
3150 			}
3151 			if (*cp == '(' || *cp == '{')
3152 			    ++nest;
3153 			if (*cp == ')' || *cp == '}') {
3154 			    --nest;
3155 			    if (nest == 0)
3156 				break;
3157 			}
3158 		    }
3159 		termc = *cp;
3160 		endpat = cp;
3161 		if (copy) {
3162 		    /*
3163 		     * Need to compress the \:'s out of the pattern, so
3164 		     * allocate enough room to hold the uncompressed
3165 		     * pattern (note that cp started at tstr+1, so
3166 		     * cp - tstr takes the null byte into account) and
3167 		     * compress the pattern into the space.
3168 		     */
3169 		    pattern = bmake_malloc(cp - tstr);
3170 		    for (cp2 = pattern, cp = tstr + 1;
3171 			 cp < endpat;
3172 			 cp++, cp2++)
3173 			{
3174 			    if ((*cp == '\\') && (cp+1 < endpat) &&
3175 				(cp[1] == ':' || cp[1] == endc)) {
3176 				cp++;
3177 			    }
3178 			    *cp2 = *cp;
3179 			}
3180 		    *cp2 = '\0';
3181 		    endpat = cp2;
3182 		} else {
3183 		    /*
3184 		     * Either Var_Subst or VarModify will need a
3185 		     * nul-terminated string soon, so construct one now.
3186 		     */
3187 		    pattern = bmake_strndup(tstr+1, endpat - (tstr + 1));
3188 		}
3189 		if (needSubst) {
3190 		    /*
3191 		     * pattern contains embedded '$', so use Var_Subst to
3192 		     * expand it.
3193 		     */
3194 		    cp2 = pattern;
3195 		    pattern = Var_Subst(NULL, cp2, ctxt, errnum);
3196 		    free(cp2);
3197 		}
3198 		if (DEBUG(VAR))
3199 		    fprintf(debug_file, "Pattern[%s] for [%s] is [%s]\n",
3200 			v->name, nstr, pattern);
3201 		if (*tstr == 'M') {
3202 		    newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
3203 				       pattern);
3204 		} else {
3205 		    newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
3206 				       pattern);
3207 		}
3208 		free(pattern);
3209 		break;
3210 	    }
3211 	case 'S':
3212 	    {
3213 		VarPattern 	    pattern;
3214 		Var_Parse_State tmpparsestate;
3215 
3216 		pattern.flags = 0;
3217 		tmpparsestate = parsestate;
3218 		delim = tstr[1];
3219 		tstr += 2;
3220 
3221 		/*
3222 		 * If pattern begins with '^', it is anchored to the
3223 		 * start of the word -- skip over it and flag pattern.
3224 		 */
3225 		if (*tstr == '^') {
3226 		    pattern.flags |= VAR_MATCH_START;
3227 		    tstr += 1;
3228 		}
3229 
3230 		cp = tstr;
3231 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
3232 						 &cp, delim,
3233 						 &pattern.flags,
3234 						 &pattern.leftLen,
3235 						 NULL)) == NULL)
3236 		    goto cleanup;
3237 
3238 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
3239 						 &cp, delim, NULL,
3240 						 &pattern.rightLen,
3241 						 &pattern)) == NULL)
3242 		    goto cleanup;
3243 
3244 		/*
3245 		 * Check for global substitution. If 'g' after the final
3246 		 * delimiter, substitution is global and is marked that
3247 		 * way.
3248 		 */
3249 		for (;; cp++) {
3250 		    switch (*cp) {
3251 		    case 'g':
3252 			pattern.flags |= VAR_SUB_GLOBAL;
3253 			continue;
3254 		    case '1':
3255 			pattern.flags |= VAR_SUB_ONE;
3256 			continue;
3257 		    case 'W':
3258 			tmpparsestate.oneBigWord = TRUE;
3259 			continue;
3260 		    }
3261 		    break;
3262 		}
3263 
3264 		termc = *cp;
3265 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
3266 				   VarSubstitute,
3267 				   &pattern);
3268 
3269 		/*
3270 		 * Free the two strings.
3271 		 */
3272 		free(UNCONST(pattern.lhs));
3273 		free(UNCONST(pattern.rhs));
3274 		delim = '\0';
3275 		break;
3276 	    }
3277 	case '?':
3278 	    {
3279 		VarPattern 	pattern;
3280 		Boolean	value;
3281 
3282 		/* find ':', and then substitute accordingly */
3283 
3284 		pattern.flags = 0;
3285 
3286 		cp = ++tstr;
3287 		delim = ':';
3288 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
3289 						 &cp, delim, NULL,
3290 						 &pattern.leftLen,
3291 						 NULL)) == NULL)
3292 		    goto cleanup;
3293 
3294 		/* BROPEN or PROPEN */
3295 		delim = endc;
3296 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
3297 						 &cp, delim, NULL,
3298 						 &pattern.rightLen,
3299 						 NULL)) == NULL)
3300 		    goto cleanup;
3301 
3302 		termc = *--cp;
3303 		delim = '\0';
3304 		if (Cond_EvalExpression(NULL, v->name, &value, 0)
3305 		    == COND_INVALID) {
3306 		    Error("Bad conditional expression `%s' in %s?%s:%s",
3307 			  v->name, v->name, pattern.lhs, pattern.rhs);
3308 		    goto cleanup;
3309 		}
3310 
3311 		if (value) {
3312 		    newStr = UNCONST(pattern.lhs);
3313 		    free(UNCONST(pattern.rhs));
3314 		} else {
3315 		    newStr = UNCONST(pattern.rhs);
3316 		    free(UNCONST(pattern.lhs));
3317 		}
3318 		if (v->flags & VAR_JUNK) {
3319 		    v->flags |= VAR_KEEP;
3320 		}
3321 		break;
3322 	    }
3323 #ifndef NO_REGEX
3324 	case 'C':
3325 	    {
3326 		VarREPattern    pattern;
3327 		char           *re;
3328 		int             error;
3329 		Var_Parse_State tmpparsestate;
3330 
3331 		pattern.flags = 0;
3332 		tmpparsestate = parsestate;
3333 		delim = tstr[1];
3334 		tstr += 2;
3335 
3336 		cp = tstr;
3337 
3338 		if ((re = VarGetPattern(ctxt, &parsestate, errnum, &cp, delim,
3339 					NULL, NULL, NULL)) == NULL)
3340 		    goto cleanup;
3341 
3342 		if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
3343 						     errnum, &cp, delim, NULL,
3344 						     NULL, NULL)) == NULL){
3345 		    free(re);
3346 		    goto cleanup;
3347 		}
3348 
3349 		for (;; cp++) {
3350 		    switch (*cp) {
3351 		    case 'g':
3352 			pattern.flags |= VAR_SUB_GLOBAL;
3353 			continue;
3354 		    case '1':
3355 			pattern.flags |= VAR_SUB_ONE;
3356 			continue;
3357 		    case 'W':
3358 			tmpparsestate.oneBigWord = TRUE;
3359 			continue;
3360 		    }
3361 		    break;
3362 		}
3363 
3364 		termc = *cp;
3365 
3366 		error = regcomp(&pattern.re, re, REG_EXTENDED);
3367 		free(re);
3368 		if (error)  {
3369 		    *lengthPtr = cp - start + 1;
3370 		    VarREError(error, &pattern.re, "RE substitution error");
3371 		    free(pattern.replace);
3372 		    goto cleanup;
3373 		}
3374 
3375 		pattern.nsub = pattern.re.re_nsub + 1;
3376 		if (pattern.nsub < 1)
3377 		    pattern.nsub = 1;
3378 		if (pattern.nsub > 10)
3379 		    pattern.nsub = 10;
3380 		pattern.matches = bmake_malloc(pattern.nsub *
3381 					  sizeof(regmatch_t));
3382 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
3383 				   VarRESubstitute,
3384 				   &pattern);
3385 		regfree(&pattern.re);
3386 		free(pattern.replace);
3387 		free(pattern.matches);
3388 		delim = '\0';
3389 		break;
3390 	    }
3391 #endif
3392 	case 'Q':
3393 	    if (tstr[1] == endc || tstr[1] == ':') {
3394 		newStr = VarQuote(nstr);
3395 		cp = tstr + 1;
3396 		termc = *cp;
3397 		break;
3398 	    }
3399 	    goto default_case;
3400 	case 'T':
3401 	    if (tstr[1] == endc || tstr[1] == ':') {
3402 		newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
3403 				   NULL);
3404 		cp = tstr + 1;
3405 		termc = *cp;
3406 		break;
3407 	    }
3408 	    goto default_case;
3409 	case 'H':
3410 	    if (tstr[1] == endc || tstr[1] == ':') {
3411 		newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
3412 				   NULL);
3413 		cp = tstr + 1;
3414 		termc = *cp;
3415 		break;
3416 	    }
3417 	    goto default_case;
3418 	case 'E':
3419 	    if (tstr[1] == endc || tstr[1] == ':') {
3420 		newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
3421 				   NULL);
3422 		cp = tstr + 1;
3423 		termc = *cp;
3424 		break;
3425 	    }
3426 	    goto default_case;
3427 	case 'R':
3428 	    if (tstr[1] == endc || tstr[1] == ':') {
3429 		newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
3430 				   NULL);
3431 		cp = tstr + 1;
3432 		termc = *cp;
3433 		break;
3434 	    }
3435 	    goto default_case;
3436 	case 'O':
3437 	    {
3438 		char otype;
3439 
3440 		cp = tstr + 1;	/* skip to the rest in any case */
3441 		if (tstr[1] == endc || tstr[1] == ':') {
3442 		    otype = 's';
3443 		    termc = *cp;
3444 		} else if ( (tstr[1] == 'x') &&
3445 			    (tstr[2] == endc || tstr[2] == ':') ) {
3446 		    otype = tstr[1];
3447 		    cp = tstr + 2;
3448 		    termc = *cp;
3449 		} else {
3450 		    goto bad_modifier;
3451 		}
3452 		newStr = VarOrder(nstr, otype);
3453 		break;
3454 	    }
3455 	case 'u':
3456 	    if (tstr[1] == endc || tstr[1] == ':') {
3457 		newStr = VarUniq(nstr);
3458 		cp = tstr + 1;
3459 		termc = *cp;
3460 		break;
3461 	    }
3462 	    goto default_case;
3463 #ifdef SUNSHCMD
3464 	case 's':
3465 	    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
3466 		const char *emsg;
3467 		newStr = Cmd_Exec(nstr, &emsg);
3468 		if (emsg)
3469 		    Error(emsg, nstr);
3470 		cp = tstr + 2;
3471 		termc = *cp;
3472 		break;
3473 	    }
3474 	    goto default_case;
3475 #endif
3476 	default:
3477 	default_case:
3478 	{
3479 #ifdef SYSVVARSUB
3480 	    /*
3481 	     * This can either be a bogus modifier or a System-V
3482 	     * substitution command.
3483 	     */
3484 	    VarPattern      pattern;
3485 	    Boolean         eqFound;
3486 
3487 	    pattern.flags = 0;
3488 	    eqFound = FALSE;
3489 	    /*
3490 	     * First we make a pass through the string trying
3491 	     * to verify it is a SYSV-make-style translation:
3492 	     * it must be: <string1>=<string2>)
3493 	     */
3494 	    cp = tstr;
3495 	    cnt = 1;
3496 	    while (*cp != '\0' && cnt) {
3497 		if (*cp == '=') {
3498 		    eqFound = TRUE;
3499 		    /* continue looking for endc */
3500 		}
3501 		else if (*cp == endc)
3502 		    cnt--;
3503 		else if (*cp == startc)
3504 		    cnt++;
3505 		if (cnt)
3506 		    cp++;
3507 	    }
3508 	    if (*cp == endc && eqFound) {
3509 
3510 		/*
3511 		 * Now we break this sucker into the lhs and
3512 		 * rhs. We must null terminate them of course.
3513 		 */
3514 		delim='=';
3515 		cp = tstr;
3516 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
3517 						 errnum, &cp, delim, &pattern.flags,
3518 						 &pattern.leftLen, NULL)) == NULL)
3519 		    goto cleanup;
3520 		delim = endc;
3521 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
3522 						 errnum, &cp, delim, NULL, &pattern.rightLen,
3523 						 &pattern)) == NULL)
3524 		    goto cleanup;
3525 
3526 		/*
3527 		 * SYSV modifications happen through the whole
3528 		 * string. Note the pattern is anchored at the end.
3529 		 */
3530 		termc = *--cp;
3531 		delim = '\0';
3532 		if (pattern.leftLen == 0 && *nstr == '\0') {
3533 		    newStr = nstr;	/* special case */
3534 		} else {
3535 		    newStr = VarModify(ctxt, &parsestate, nstr,
3536 				       VarSYSVMatch,
3537 				       &pattern);
3538 		}
3539 		free(UNCONST(pattern.lhs));
3540 		free(UNCONST(pattern.rhs));
3541 	    } else
3542 #endif
3543 		{
3544 		    Error("Unknown modifier '%c'", *tstr);
3545 		    for (cp = tstr+1;
3546 			 *cp != ':' && *cp != endc && *cp != '\0';
3547 			 cp++)
3548 			continue;
3549 		    termc = *cp;
3550 		    newStr = var_Error;
3551 		}
3552 	    }
3553 	}
3554 	if (DEBUG(VAR)) {
3555 	    fprintf(debug_file, "Result[%s] of :%c is \"%s\"\n",
3556 		v->name, modifier, newStr);
3557 	}
3558 
3559 	if (newStr != nstr) {
3560 	    if (*freePtr) {
3561 		free(nstr);
3562 		*freePtr = NULL;
3563 	    }
3564 	    nstr = newStr;
3565 	    if (nstr != var_Error && nstr != varNoError) {
3566 		*freePtr = nstr;
3567 	    }
3568 	}
3569 	if (termc == '\0' && endc != '\0') {
3570 	    Error("Unclosed variable specification (expecting '%c') for \"%s\" (value \"%s\") modifier %c", endc, v->name, nstr, modifier);
3571 	} else if (termc == ':') {
3572 	    cp++;
3573 	}
3574 	tstr = cp;
3575     }
3576  out:
3577     *lengthPtr = tstr - start;
3578     return (nstr);
3579 
3580  bad_modifier:
3581     /* "{(" */
3582     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
3583 	  v->name);
3584 
3585  cleanup:
3586     *lengthPtr = cp - start;
3587     if (delim != '\0')
3588 	Error("Unclosed substitution for %s (%c missing)",
3589 	      v->name, delim);
3590     if (*freePtr) {
3591 	free(*freePtr);
3592 	*freePtr = NULL;
3593     }
3594     return (var_Error);
3595 }
3596 
3597 /*-
3598  *-----------------------------------------------------------------------
3599  * Var_Parse --
3600  *	Given the start of a variable invocation, extract the variable
3601  *	name and find its value, then modify it according to the
3602  *	specification.
3603  *
3604  * Input:
3605  *	str		The string to parse
3606  *	ctxt		The context for the variable
3607  *	errnum		TRUE if undefined variables are an error
3608  *	lengthPtr	OUT: The length of the specification
3609  *	freePtr		OUT: Non-NULL if caller should free *freePtr
3610  *
3611  * Results:
3612  *	The (possibly-modified) value of the variable or var_Error if the
3613  *	specification is invalid. The length of the specification is
3614  *	placed in *lengthPtr (for invalid specifications, this is just
3615  *	2...?).
3616  *	If *freePtr is non-NULL then it's a pointer that the caller
3617  *	should pass to free() to free memory used by the result.
3618  *
3619  * Side Effects:
3620  *	None.
3621  *
3622  *-----------------------------------------------------------------------
3623  */
3624 /* coverity[+alloc : arg-*4] */
3625 char *
3626 Var_Parse(const char *str, GNode *ctxt, Boolean errnum, int *lengthPtr,
3627 	  void **freePtr)
3628 {
3629     const char	   *tstr;    	/* Pointer into str */
3630     Var		   *v;		/* Variable in invocation */
3631     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
3632     char	    endc;    	/* Ending character when variable in parens
3633 				 * or braces */
3634     char	    startc;	/* Starting character when variable in parens
3635 				 * or braces */
3636     int		    vlen;	/* Length of variable name */
3637     const char 	   *start;	/* Points to original start of str */
3638     char	   *nstr;	/* New string, used during expansion */
3639     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
3640 				 * expanding it in a non-local context. This
3641 				 * is done to support dynamic sources. The
3642 				 * result is just the invocation, unaltered */
3643     Var_Parse_State parsestate; /* Flags passed to helper functions */
3644     char	  name[2];
3645 
3646     *freePtr = NULL;
3647     dynamic = FALSE;
3648     start = str;
3649     parsestate.oneBigWord = FALSE;
3650     parsestate.varSpace = ' ';	/* word separator */
3651 
3652     startc = str[1];
3653     if (startc != PROPEN && startc != BROPEN) {
3654 	/*
3655 	 * If it's not bounded by braces of some sort, life is much simpler.
3656 	 * We just need to check for the first character and return the
3657 	 * value if it exists.
3658 	 */
3659 
3660 	/* Error out some really stupid names */
3661 	if (startc == '\0' || strchr(")}:$", startc)) {
3662 	    *lengthPtr = 1;
3663 	    return var_Error;
3664 	}
3665 	name[0] = startc;
3666 	name[1] = '\0';
3667 
3668 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3669 	if (v == NULL) {
3670 	    *lengthPtr = 2;
3671 
3672 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
3673 		/*
3674 		 * If substituting a local variable in a non-local context,
3675 		 * assume it's for dynamic source stuff. We have to handle
3676 		 * this specially and return the longhand for the variable
3677 		 * with the dollar sign escaped so it makes it back to the
3678 		 * caller. Only four of the local variables are treated
3679 		 * specially as they are the only four that will be set
3680 		 * when dynamic sources are expanded.
3681 		 */
3682 		switch (str[1]) {
3683 		    case '@':
3684 			return UNCONST("$(.TARGET)");
3685 		    case '%':
3686 			return UNCONST("$(.ARCHIVE)");
3687 		    case '*':
3688 			return UNCONST("$(.PREFIX)");
3689 		    case '!':
3690 			return UNCONST("$(.MEMBER)");
3691 		}
3692 	    }
3693 	    /*
3694 	     * Error
3695 	     */
3696 	    return (errnum ? var_Error : varNoError);
3697 	} else {
3698 	    haveModifier = FALSE;
3699 	    tstr = &str[1];
3700 	    endc = str[1];
3701 	}
3702     } else {
3703 	Buffer buf;	/* Holds the variable name */
3704 
3705 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
3706 	Buf_Init(&buf, 0);
3707 
3708 	/*
3709 	 * Skip to the end character or a colon, whichever comes first.
3710 	 */
3711 	for (tstr = str + 2;
3712 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
3713 	     tstr++)
3714 	{
3715 	    /*
3716 	     * A variable inside a variable, expand
3717 	     */
3718 	    if (*tstr == '$') {
3719 		int rlen;
3720 		void *freeIt;
3721 		char *rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
3722 		if (rval != NULL) {
3723 		    Buf_AddBytes(&buf, strlen(rval), rval);
3724 		}
3725 		if (freeIt)
3726 		    free(freeIt);
3727 		tstr += rlen - 1;
3728 	    }
3729 	    else
3730 		Buf_AddByte(&buf, *tstr);
3731 	}
3732 	if (*tstr == ':') {
3733 	    haveModifier = TRUE;
3734 	} else if (*tstr != '\0') {
3735 	    haveModifier = FALSE;
3736 	} else {
3737 	    /*
3738 	     * If we never did find the end character, return NULL
3739 	     * right now, setting the length to be the distance to
3740 	     * the end of the string, since that's what make does.
3741 	     */
3742 	    *lengthPtr = tstr - str;
3743 	    Buf_Destroy(&buf, TRUE);
3744 	    return (var_Error);
3745 	}
3746 	str = Buf_GetAll(&buf, &vlen);
3747 
3748 	/*
3749 	 * At this point, str points into newly allocated memory from
3750 	 * buf, containing only the name of the variable.
3751 	 *
3752 	 * start and tstr point into the const string that was pointed
3753 	 * to by the original value of the str parameter.  start points
3754 	 * to the '$' at the beginning of the string, while tstr points
3755 	 * to the char just after the end of the variable name -- this
3756 	 * will be '\0', ':', PRCLOSE, or BRCLOSE.
3757 	 */
3758 
3759 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3760 	/*
3761 	 * Check also for bogus D and F forms of local variables since we're
3762 	 * in a local context and the name is the right length.
3763 	 */
3764 	if ((v == NULL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
3765 		(vlen == 2) && (str[1] == 'F' || str[1] == 'D') &&
3766 		strchr("@%*!<>", str[0]) != NULL) {
3767 	    /*
3768 	     * Well, it's local -- go look for it.
3769 	     */
3770 	    name[0] = *str;
3771 	    name[1] = '\0';
3772 	    v = VarFind(name, ctxt, 0);
3773 
3774 	    if (v != NULL) {
3775 		/*
3776 		 * No need for nested expansion or anything, as we're
3777 		 * the only one who sets these things and we sure don't
3778 		 * but nested invocations in them...
3779 		 */
3780 		nstr = Buf_GetAll(&v->val, NULL);
3781 
3782 		if (str[1] == 'D') {
3783 		    nstr = VarModify(ctxt, &parsestate, nstr, VarHead,
3784 				    NULL);
3785 		} else {
3786 		    nstr = VarModify(ctxt, &parsestate, nstr, VarTail,
3787 				    NULL);
3788 		}
3789 		/*
3790 		 * Resulting string is dynamically allocated, so
3791 		 * tell caller to free it.
3792 		 */
3793 		*freePtr = nstr;
3794 		*lengthPtr = tstr-start+1;
3795 		Buf_Destroy(&buf, TRUE);
3796 		VarFreeEnv(v, TRUE);
3797 		return nstr;
3798 	    }
3799 	}
3800 
3801 	if (v == NULL) {
3802 	    if (((vlen == 1) ||
3803 		 (((vlen == 2) && (str[1] == 'F' || str[1] == 'D')))) &&
3804 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3805 	    {
3806 		/*
3807 		 * If substituting a local variable in a non-local context,
3808 		 * assume it's for dynamic source stuff. We have to handle
3809 		 * this specially and return the longhand for the variable
3810 		 * with the dollar sign escaped so it makes it back to the
3811 		 * caller. Only four of the local variables are treated
3812 		 * specially as they are the only four that will be set
3813 		 * when dynamic sources are expanded.
3814 		 */
3815 		switch (*str) {
3816 		    case '@':
3817 		    case '%':
3818 		    case '*':
3819 		    case '!':
3820 			dynamic = TRUE;
3821 			break;
3822 		}
3823 	    } else if ((vlen > 2) && (*str == '.') &&
3824 		       isupper((unsigned char) str[1]) &&
3825 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3826 	    {
3827 		int	len;
3828 
3829 		len = vlen - 1;
3830 		if ((strncmp(str, ".TARGET", len) == 0) ||
3831 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
3832 		    (strncmp(str, ".PREFIX", len) == 0) ||
3833 		    (strncmp(str, ".MEMBER", len) == 0))
3834 		{
3835 		    dynamic = TRUE;
3836 		}
3837 	    }
3838 
3839 	    if (!haveModifier) {
3840 		/*
3841 		 * No modifiers -- have specification length so we can return
3842 		 * now.
3843 		 */
3844 		*lengthPtr = tstr - start + 1;
3845 		if (dynamic) {
3846 		    char *pstr = bmake_strndup(start, *lengthPtr);
3847 		    *freePtr = pstr;
3848 		    Buf_Destroy(&buf, TRUE);
3849 		    return(pstr);
3850 		} else {
3851 		    Buf_Destroy(&buf, TRUE);
3852 		    return (errnum ? var_Error : varNoError);
3853 		}
3854 	    } else {
3855 		/*
3856 		 * Still need to get to the end of the variable specification,
3857 		 * so kludge up a Var structure for the modifications
3858 		 */
3859 		v = bmake_malloc(sizeof(Var));
3860 		v->name = UNCONST(str);
3861 		Buf_Init(&v->val, 1);
3862 		v->flags = VAR_JUNK;
3863 		Buf_Destroy(&buf, FALSE);
3864 	    }
3865 	} else
3866 	    Buf_Destroy(&buf, TRUE);
3867     }
3868 
3869     if (v->flags & VAR_IN_USE) {
3870 	Fatal("Variable %s is recursive.", v->name);
3871 	/*NOTREACHED*/
3872     } else {
3873 	v->flags |= VAR_IN_USE;
3874     }
3875     /*
3876      * Before doing any modification, we have to make sure the value
3877      * has been fully expanded. If it looks like recursion might be
3878      * necessary (there's a dollar sign somewhere in the variable's value)
3879      * we just call Var_Subst to do any other substitutions that are
3880      * necessary. Note that the value returned by Var_Subst will have
3881      * been dynamically-allocated, so it will need freeing when we
3882      * return.
3883      */
3884     nstr = Buf_GetAll(&v->val, NULL);
3885     if (strchr(nstr, '$') != NULL) {
3886 	nstr = Var_Subst(NULL, nstr, ctxt, errnum);
3887 	*freePtr = nstr;
3888     }
3889 
3890     v->flags &= ~VAR_IN_USE;
3891 
3892     if ((nstr != NULL) && haveModifier) {
3893 	int used;
3894 	/*
3895 	 * Skip initial colon.
3896 	 */
3897 	tstr++;
3898 
3899 	nstr = ApplyModifiers(nstr, tstr, startc, endc,
3900 			      v, ctxt, errnum, &used, freePtr);
3901 	tstr += used;
3902     }
3903     if (*tstr) {
3904 	*lengthPtr = tstr - start + 1;
3905     } else {
3906 	*lengthPtr = tstr - start;
3907     }
3908 
3909     if (v->flags & VAR_FROM_ENV) {
3910 	Boolean	  destroy = FALSE;
3911 
3912 	if (nstr != Buf_GetAll(&v->val, NULL)) {
3913 	    destroy = TRUE;
3914 	} else {
3915 	    /*
3916 	     * Returning the value unmodified, so tell the caller to free
3917 	     * the thing.
3918 	     */
3919 	    *freePtr = nstr;
3920 	}
3921 	VarFreeEnv(v, destroy);
3922     } else if (v->flags & VAR_JUNK) {
3923 	/*
3924 	 * Perform any free'ing needed and set *freePtr to NULL so the caller
3925 	 * doesn't try to free a static pointer.
3926 	 * If VAR_KEEP is also set then we want to keep str as is.
3927 	 */
3928 	if (!(v->flags & VAR_KEEP)) {
3929 	    if (*freePtr) {
3930 		free(nstr);
3931 		*freePtr = NULL;
3932 	    }
3933 	    if (dynamic) {
3934 		nstr = bmake_strndup(start, *lengthPtr);
3935 		*freePtr = nstr;
3936 	    } else {
3937 		nstr = errnum ? var_Error : varNoError;
3938 	    }
3939 	}
3940 	if (nstr != Buf_GetAll(&v->val, NULL))
3941 	    Buf_Destroy(&v->val, TRUE);
3942 	free(v->name);
3943 	free(v);
3944     }
3945     return (nstr);
3946 }
3947 
3948 /*-
3949  *-----------------------------------------------------------------------
3950  * Var_Subst  --
3951  *	Substitute for all variables in the given string in the given context
3952  *	If undefErr is TRUE, Parse_Error will be called when an undefined
3953  *	variable is encountered.
3954  *
3955  * Input:
3956  *	var		Named variable || NULL for all
3957  *	str		the string which to substitute
3958  *	ctxt		the context wherein to find variables
3959  *	undefErr	TRUE if undefineds are an error
3960  *
3961  * Results:
3962  *	The resulting string.
3963  *
3964  * Side Effects:
3965  *	None. The old string must be freed by the caller
3966  *-----------------------------------------------------------------------
3967  */
3968 char *
3969 Var_Subst(const char *var, const char *str, GNode *ctxt, Boolean undefErr)
3970 {
3971     Buffer  	  buf;		    /* Buffer for forming things */
3972     char    	  *val;		    /* Value to substitute for a variable */
3973     int		  length;   	    /* Length of the variable invocation */
3974     Boolean	  trailingBslash;   /* variable ends in \ */
3975     void 	  *freeIt = NULL;    /* Set if it should be freed */
3976     static Boolean errorReported;   /* Set true if an error has already
3977 				     * been reported to prevent a plethora
3978 				     * of messages when recursing */
3979 
3980     Buf_Init(&buf, 0);
3981     errorReported = FALSE;
3982     trailingBslash = FALSE;
3983 
3984     while (*str) {
3985 	if (*str == '\n' && trailingBslash)
3986 	    Buf_AddByte(&buf, ' ');
3987 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
3988 	    /*
3989 	     * A dollar sign may be escaped either with another dollar sign.
3990 	     * In such a case, we skip over the escape character and store the
3991 	     * dollar sign into the buffer directly.
3992 	     */
3993 	    str++;
3994 	    Buf_AddByte(&buf, *str);
3995 	    str++;
3996 	} else if (*str != '$') {
3997 	    /*
3998 	     * Skip as many characters as possible -- either to the end of
3999 	     * the string or to the next dollar sign (variable invocation).
4000 	     */
4001 	    const char  *cp;
4002 
4003 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
4004 		continue;
4005 	    Buf_AddBytes(&buf, str - cp, cp);
4006 	} else {
4007 	    if (var != NULL) {
4008 		int expand;
4009 		for (;;) {
4010 		    if (str[1] == '\0') {
4011 			/* A trailing $ is kind of a special case */
4012 			Buf_AddByte(&buf, str[0]);
4013 			str++;
4014 			expand = FALSE;
4015 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
4016 			if (str[1] != *var || strlen(var) > 1) {
4017 			    Buf_AddBytes(&buf, 2, str);
4018 			    str += 2;
4019 			    expand = FALSE;
4020 			}
4021 			else
4022 			    expand = TRUE;
4023 			break;
4024 		    }
4025 		    else {
4026 			const char *p;
4027 
4028 			/*
4029 			 * Scan up to the end of the variable name.
4030 			 */
4031 			for (p = &str[2]; *p &&
4032 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
4033 			    if (*p == '$')
4034 				break;
4035 			/*
4036 			 * A variable inside the variable. We cannot expand
4037 			 * the external variable yet, so we try again with
4038 			 * the nested one
4039 			 */
4040 			if (*p == '$') {
4041 			    Buf_AddBytes(&buf, p - str, str);
4042 			    str = p;
4043 			    continue;
4044 			}
4045 
4046 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
4047 			    var[p - str - 2] != '\0') {
4048 			    /*
4049 			     * Not the variable we want to expand, scan
4050 			     * until the next variable
4051 			     */
4052 			    for (;*p != '$' && *p != '\0'; p++)
4053 				continue;
4054 			    Buf_AddBytes(&buf, p - str, str);
4055 			    str = p;
4056 			    expand = FALSE;
4057 			}
4058 			else
4059 			    expand = TRUE;
4060 			break;
4061 		    }
4062 		}
4063 		if (!expand)
4064 		    continue;
4065 	    }
4066 
4067 	    val = Var_Parse(str, ctxt, undefErr, &length, &freeIt);
4068 
4069 	    /*
4070 	     * When we come down here, val should either point to the
4071 	     * value of this variable, suitably modified, or be NULL.
4072 	     * Length should be the total length of the potential
4073 	     * variable invocation (from $ to end character...)
4074 	     */
4075 	    if (val == var_Error || val == varNoError) {
4076 		/*
4077 		 * If performing old-time variable substitution, skip over
4078 		 * the variable and continue with the substitution. Otherwise,
4079 		 * store the dollar sign and advance str so we continue with
4080 		 * the string...
4081 		 */
4082 		if (oldVars) {
4083 		    str += length;
4084 		} else if (undefErr) {
4085 		    /*
4086 		     * If variable is undefined, complain and skip the
4087 		     * variable. The complaint will stop us from doing anything
4088 		     * when the file is parsed.
4089 		     */
4090 		    if (!errorReported) {
4091 			Parse_Error(PARSE_FATAL,
4092 				     "Undefined variable \"%.*s\"",length,str);
4093 		    }
4094 		    str += length;
4095 		    errorReported = TRUE;
4096 		} else {
4097 		    Buf_AddByte(&buf, *str);
4098 		    str += 1;
4099 		}
4100 	    } else {
4101 		/*
4102 		 * We've now got a variable structure to store in. But first,
4103 		 * advance the string pointer.
4104 		 */
4105 		str += length;
4106 
4107 		/*
4108 		 * Copy all the characters from the variable value straight
4109 		 * into the new string.
4110 		 */
4111 		length = strlen(val);
4112 		Buf_AddBytes(&buf, length, val);
4113 		trailingBslash = length > 0 && val[length - 1] == '\\';
4114 	    }
4115 	    if (freeIt) {
4116 		free(freeIt);
4117 		freeIt = NULL;
4118 	    }
4119 	}
4120     }
4121 
4122     return Buf_DestroyCompact(&buf);
4123 }
4124 
4125 /*-
4126  *-----------------------------------------------------------------------
4127  * Var_GetTail --
4128  *	Return the tail from each of a list of words. Used to set the
4129  *	System V local variables.
4130  *
4131  * Input:
4132  *	file		Filename to modify
4133  *
4134  * Results:
4135  *	The resulting string.
4136  *
4137  * Side Effects:
4138  *	None.
4139  *
4140  *-----------------------------------------------------------------------
4141  */
4142 #if 0
4143 char *
4144 Var_GetTail(char *file)
4145 {
4146     return(VarModify(file, VarTail, NULL));
4147 }
4148 
4149 /*-
4150  *-----------------------------------------------------------------------
4151  * Var_GetHead --
4152  *	Find the leading components of a (list of) filename(s).
4153  *	XXX: VarHead does not replace foo by ., as (sun) System V make
4154  *	does.
4155  *
4156  * Input:
4157  *	file		Filename to manipulate
4158  *
4159  * Results:
4160  *	The leading components.
4161  *
4162  * Side Effects:
4163  *	None.
4164  *
4165  *-----------------------------------------------------------------------
4166  */
4167 char *
4168 Var_GetHead(char *file)
4169 {
4170     return(VarModify(file, VarHead, NULL));
4171 }
4172 #endif
4173 
4174 /*-
4175  *-----------------------------------------------------------------------
4176  * Var_Init --
4177  *	Initialize the module
4178  *
4179  * Results:
4180  *	None
4181  *
4182  * Side Effects:
4183  *	The VAR_CMD and VAR_GLOBAL contexts are created
4184  *-----------------------------------------------------------------------
4185  */
4186 void
4187 Var_Init(void)
4188 {
4189     VAR_GLOBAL = Targ_NewGN("Global");
4190     VAR_CMD = Targ_NewGN("Command");
4191 
4192 }
4193 
4194 
4195 void
4196 Var_End(void)
4197 {
4198 }
4199 
4200 
4201 /****************** PRINT DEBUGGING INFO *****************/
4202 static void
4203 VarPrintVar(void *vp)
4204 {
4205     Var    *v = (Var *)vp;
4206     fprintf(debug_file, "%-16s = %s\n", v->name, Buf_GetAll(&v->val, NULL));
4207 }
4208 
4209 /*-
4210  *-----------------------------------------------------------------------
4211  * Var_Dump --
4212  *	print all variables in a context
4213  *-----------------------------------------------------------------------
4214  */
4215 void
4216 Var_Dump(GNode *ctxt)
4217 {
4218     Hash_Search search;
4219     Hash_Entry *h;
4220 
4221     for (h = Hash_EnumFirst(&ctxt->context, &search);
4222 	 h != NULL;
4223 	 h = Hash_EnumNext(&search)) {
4224 	    VarPrintVar(Hash_GetValue(h));
4225     }
4226 }
4227