xref: /netbsd-src/usr.bin/make/var.c (revision 2980e352a13e8f0b545a366830c411e7a542ada8)
1 /*	$NetBSD: var.c,v 1.131 2008/05/15 21:05:54 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 1.131 2008/05/15 21:05:54 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 1.131 2008/05/15 21:05:54 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 #ifndef NO_REGEX
127 #include    <sys/types.h>
128 #include    <regex.h>
129 #endif
130 #include    <ctype.h>
131 #include    <stdlib.h>
132 #include    <limits.h>
133 
134 #include    "make.h"
135 #include    "buf.h"
136 #include    "dir.h"
137 #include    "job.h"
138 
139 /*
140  * This is a harmless return value for Var_Parse that can be used by Var_Subst
141  * to determine if there was an error in parsing -- easier than returning
142  * a flag, as things outside this module don't give a hoot.
143  */
144 char 	var_Error[] = "";
145 
146 /*
147  * Similar to var_Error, but returned when the 'errnum' flag for Var_Parse is
148  * set false. Why not just use a constant? Well, gcc likes to condense
149  * identical string instances...
150  */
151 static char	varNoError[] = "";
152 
153 /*
154  * Internally, variables are contained in four different contexts.
155  *	1) the environment. They may not be changed. If an environment
156  *	    variable is appended-to, the result is placed in the global
157  *	    context.
158  *	2) the global context. Variables set in the Makefile are located in
159  *	    the global context. It is the penultimate context searched when
160  *	    substituting.
161  *	3) the command-line context. All variables set on the command line
162  *	   are placed in this context. They are UNALTERABLE once placed here.
163  *	4) the local context. Each target has associated with it a context
164  *	   list. On this list are located the structures describing such
165  *	   local variables as $(@) and $(*)
166  * The four contexts are searched in the reverse order from which they are
167  * listed.
168  */
169 GNode          *VAR_GLOBAL;   /* variables from the makefile */
170 GNode          *VAR_CMD;      /* variables defined on the command-line */
171 
172 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
173 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
174 #define FIND_ENV  	0x4   /* look in the environment also */
175 
176 typedef struct Var {
177     char          *name;	/* the variable's name */
178     Buffer	  val;	    	/* its value */
179     int	    	  flags;    	/* miscellaneous status flags */
180 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
181 				     * Used to avoid recursion */
182 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
183 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
184 				     * should be destroyed when done with
185 				     * it. Used by Var_Parse for undefined,
186 				     * modified variables */
187 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
188 				     * a use for it in some modifier and
189 				     * the value is therefore valid */
190 #define VAR_EXPORTED	16 	    /* Variable is exported */
191 #define VAR_REEXPORT	32	    /* Indicate if var needs re-export.
192 				     * This would be true if it contains $'s
193 				     */
194 #define VAR_FROM_CMD	64 	    /* Variable came from command line */
195 }  Var;
196 
197 /*
198  * Exporting vars is expensive so skip it if we can
199  */
200 #define VAR_EXPORTED_NONE	0
201 #define VAR_EXPORTED_YES	1
202 #define VAR_EXPORTED_ALL	2
203 static int var_exportedVars = VAR_EXPORTED_NONE;
204 /*
205  * We pass this to Var_Export when doing the initial export
206  * or after updating an exported var.
207  */
208 #define VAR_EXPORT_FORCE 1
209 
210 /* Var*Pattern flags */
211 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
212 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
213 #define VAR_SUB_MATCHED	0x04	/* There was a match */
214 #define VAR_MATCH_START	0x08	/* Match at start of word */
215 #define VAR_MATCH_END	0x10	/* Match at end of word */
216 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
217 
218 /* Var_Set flags */
219 #define VAR_NO_EXPORT	0x01	/* do not export */
220 
221 typedef struct {
222     /*
223      * The following fields are set by Var_Parse() when it
224      * encounters modifiers that need to keep state for use by
225      * subsequent modifiers within the same variable expansion.
226      */
227     Byte	varSpace;	/* Word separator in expansions */
228     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
229 				 * single big word, even if it contains
230 				 * embedded spaces (as opposed to the
231 				 * usual behaviour of treating it as
232 				 * several space-separated words). */
233 } Var_Parse_State;
234 
235 /* struct passed as ClientData to VarSubstitute() for ":S/lhs/rhs/",
236  * to VarSYSVMatch() for ":lhs=rhs". */
237 typedef struct {
238     const char   *lhs;	    /* String to match */
239     int	    	  leftLen; /* Length of string */
240     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
241     int	    	  rightLen; /* Length of replacement */
242     int	    	  flags;
243 } VarPattern;
244 
245 /* struct passed as ClientData to VarLoopExpand() for ":@tvar@str@" */
246 typedef struct {
247     GNode	*ctxt;		/* variable context */
248     char	*tvar;		/* name of temp var */
249     int		tvarLen;
250     char	*str;		/* string to expand */
251     int		strLen;
252     int		errnum;		/* errnum for not defined */
253 } VarLoop_t;
254 
255 #ifndef NO_REGEX
256 /* struct passed as ClientData to VarRESubstitute() for ":C///" */
257 typedef struct {
258     regex_t	   re;
259     int		   nsub;
260     regmatch_t 	  *matches;
261     char 	  *replace;
262     int		   flags;
263 } VarREPattern;
264 #endif
265 
266 /* struct passed to VarSelectWords() for ":[start..end]" */
267 typedef struct {
268     int		start;		/* first word to select */
269     int		end;		/* last word to select */
270 } VarSelectWords_t;
271 
272 static Var *VarFind(const char *, GNode *, int);
273 static void VarAdd(const char *, const char *, GNode *);
274 static Boolean VarHead(GNode *, Var_Parse_State *,
275 			char *, Boolean, Buffer, ClientData);
276 static Boolean VarTail(GNode *, Var_Parse_State *,
277 			char *, Boolean, Buffer, ClientData);
278 static Boolean VarSuffix(GNode *, Var_Parse_State *,
279 			char *, Boolean, Buffer, ClientData);
280 static Boolean VarRoot(GNode *, Var_Parse_State *,
281 			char *, Boolean, Buffer, ClientData);
282 static Boolean VarMatch(GNode *, Var_Parse_State *,
283 			char *, Boolean, Buffer, ClientData);
284 #ifdef SYSVVARSUB
285 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
286 			char *, Boolean, Buffer, ClientData);
287 #endif
288 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
289 			char *, Boolean, Buffer, ClientData);
290 #ifndef NO_REGEX
291 static void VarREError(int, regex_t *, const char *);
292 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
293 			char *, Boolean, Buffer, ClientData);
294 #endif
295 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
296 			char *, Boolean, Buffer, ClientData);
297 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
298 			char *, Boolean, Buffer, ClientData);
299 static char *VarGetPattern(GNode *, Var_Parse_State *,
300 			   int, const char **, int, int *, int *,
301 			   VarPattern *);
302 static char *VarQuote(char *);
303 static char *VarChangeCase(char *, int);
304 static char *VarModify(GNode *, Var_Parse_State *,
305     const char *,
306     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer, ClientData),
307     ClientData);
308 static char *VarOrder(const char *, const char);
309 static char *VarUniq(const char *);
310 static int VarWordCompare(const void *, const void *);
311 static void VarPrintVar(ClientData);
312 
313 #define BROPEN	'{'
314 #define BRCLOSE	'}'
315 #define PROPEN	'('
316 #define PRCLOSE	')'
317 
318 /*-
319  *-----------------------------------------------------------------------
320  * VarFind --
321  *	Find the given variable in the given context and any other contexts
322  *	indicated.
323  *
324  * Input:
325  *	name		name to find
326  *	ctxt		context in which to find it
327  *	flags		FIND_GLOBAL set means to look in the
328  *			VAR_GLOBAL context as well. FIND_CMD set means
329  *			to look in the VAR_CMD context also. FIND_ENV
330  *			set means to look in the environment
331  *
332  * Results:
333  *	A pointer to the structure describing the desired variable or
334  *	NIL if the variable does not exist.
335  *
336  * Side Effects:
337  *	None
338  *-----------------------------------------------------------------------
339  */
340 static Var *
341 VarFind(const char *name, GNode *ctxt, int flags)
342 {
343     Hash_Entry         	*var;
344     Var		  	*v;
345 
346 	/*
347 	 * If the variable name begins with a '.', it could very well be one of
348 	 * the local ones.  We check the name against all the local variables
349 	 * and substitute the short version in for 'name' if it matches one of
350 	 * them.
351 	 */
352 	if (*name == '.' && isupper((unsigned char) name[1]))
353 		switch (name[1]) {
354 		case 'A':
355 			if (!strcmp(name, ".ALLSRC"))
356 				name = ALLSRC;
357 			if (!strcmp(name, ".ARCHIVE"))
358 				name = ARCHIVE;
359 			break;
360 		case 'I':
361 			if (!strcmp(name, ".IMPSRC"))
362 				name = IMPSRC;
363 			break;
364 		case 'M':
365 			if (!strcmp(name, ".MEMBER"))
366 				name = MEMBER;
367 			break;
368 		case 'O':
369 			if (!strcmp(name, ".OODATE"))
370 				name = OODATE;
371 			break;
372 		case 'P':
373 			if (!strcmp(name, ".PREFIX"))
374 				name = PREFIX;
375 			break;
376 		case 'T':
377 			if (!strcmp(name, ".TARGET"))
378 				name = TARGET;
379 			break;
380 		}
381     /*
382      * First look for the variable in the given context. If it's not there,
383      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
384      * depending on the FIND_* flags in 'flags'
385      */
386     var = Hash_FindEntry(&ctxt->context, name);
387 
388     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
389 	var = Hash_FindEntry(&VAR_CMD->context, name);
390     }
391     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
392 	(ctxt != VAR_GLOBAL))
393     {
394 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
395     }
396     if ((var == NULL) && (flags & FIND_ENV)) {
397 	char *env;
398 
399 	if ((env = getenv(name)) != NULL) {
400 	    int	  	len;
401 
402 	    v = emalloc(sizeof(Var));
403 	    v->name = estrdup(name);
404 
405 	    len = strlen(env);
406 
407 	    v->val = Buf_Init(len + 1);
408 	    Buf_AddBytes(v->val, len, (Byte *)env);
409 
410 	    v->flags = VAR_FROM_ENV;
411 	    return (v);
412 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
413 		   (ctxt != VAR_GLOBAL))
414 	{
415 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
416 	    if (var == NULL) {
417 		return ((Var *)NIL);
418 	    } else {
419 		return ((Var *)Hash_GetValue(var));
420 	    }
421 	} else {
422 	    return((Var *)NIL);
423 	}
424     } else if (var == NULL) {
425 	return ((Var *)NIL);
426     } else {
427 	return ((Var *)Hash_GetValue(var));
428     }
429 }
430 
431 /*-
432  *-----------------------------------------------------------------------
433  * VarFreeEnv  --
434  *	If the variable is an environment variable, free it
435  *
436  * Input:
437  *	v		the variable
438  *	destroy		true if the value buffer should be destroyed.
439  *
440  * Results:
441  *	1 if it is an environment variable 0 ow.
442  *
443  * Side Effects:
444  *	The variable is free'ed if it is an environent variable.
445  *-----------------------------------------------------------------------
446  */
447 static Boolean
448 VarFreeEnv(Var *v, Boolean destroy)
449 {
450     if ((v->flags & VAR_FROM_ENV) == 0)
451 	return FALSE;
452     free(v->name);
453     Buf_Destroy(v->val, destroy);
454     free(v);
455     return TRUE;
456 }
457 
458 /*-
459  *-----------------------------------------------------------------------
460  * VarAdd  --
461  *	Add a new variable of name name and value val to the given context
462  *
463  * Input:
464  *	name		name of variable to add
465  *	val		value to set it to
466  *	ctxt		context in which to set it
467  *
468  * Results:
469  *	None
470  *
471  * Side Effects:
472  *	The new variable is placed at the front of the given context
473  *	The name and val arguments are duplicated so they may
474  *	safely be freed.
475  *-----------------------------------------------------------------------
476  */
477 static void
478 VarAdd(const char *name, const char *val, GNode *ctxt)
479 {
480     Var   	  *v;
481     int	    	  len;
482     Hash_Entry    *h;
483 
484     v = emalloc(sizeof(Var));
485 
486     len = val ? strlen(val) : 0;
487     v->val = Buf_Init(len+1);
488     Buf_AddBytes(v->val, len, (const Byte *)val);
489 
490     v->flags = 0;
491 
492     h = Hash_CreateEntry(&ctxt->context, name, NULL);
493     Hash_SetValue(h, v);
494     v->name = h->name;
495     if (DEBUG(VAR)) {
496 	fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
497     }
498 }
499 
500 /*-
501  *-----------------------------------------------------------------------
502  * Var_Delete --
503  *	Remove a variable from a context.
504  *
505  * Results:
506  *	None.
507  *
508  * Side Effects:
509  *	The Var structure is removed and freed.
510  *
511  *-----------------------------------------------------------------------
512  */
513 void
514 Var_Delete(const char *name, GNode *ctxt)
515 {
516     Hash_Entry 	  *ln;
517 
518     ln = Hash_FindEntry(&ctxt->context, name);
519     if (DEBUG(VAR)) {
520 	fprintf(debug_file, "%s:delete %s%s\n",
521 	    ctxt->name, name, ln ? "" : " (not found)");
522     }
523     if (ln != NULL) {
524 	Var 	  *v;
525 
526 	v = (Var *)Hash_GetValue(ln);
527 	if ((v->flags & VAR_EXPORTED)) {
528 	    unsetenv(v->name);
529 	}
530 	if (v->name != ln->name)
531 		free(v->name);
532 	Hash_DeleteEntry(&ctxt->context, ln);
533 	Buf_Destroy(v->val, TRUE);
534 	free(v);
535     }
536 }
537 
538 
539 /*
540  * Export a var.
541  * We ignore make internal variables (those which start with '.')
542  * Also we jump through some hoops to avoid calling setenv
543  * more than necessary since it can leak.
544  */
545 static int
546 Var_Export1(const char *name, int force)
547 {
548     char tmp[BUFSIZ];
549     Var *v;
550     char *val = NULL;
551     int n;
552 
553     if (*name == '.')
554 	return 0;			/* skip internals */
555     if (!name[1]) {
556 	/*
557 	 * A single char.
558 	 * If it is one of the vars that should only appear in
559 	 * local context, skip it, else we can get Var_Subst
560 	 * into a loop.
561 	 */
562 	switch (name[0]) {
563 	case '@':
564 	case '%':
565 	case '*':
566 	case '!':
567 	    return 0;
568 	}
569     }
570     v = VarFind(name, VAR_GLOBAL, 0);
571     if (v == (Var *)NIL) {
572 	return 0;
573     }
574     if (!force &&
575 	(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
576 	return 0;			/* nothing to do */
577     }
578     val = (char *)Buf_GetAll(v->val, NULL);
579     if (strchr(val, '$')) {
580 	/* Flag this as something we need to re-export */
581 	v->flags |= (VAR_EXPORTED|VAR_REEXPORT);
582 	if (force) {
583 	    /*
584 	     * No point actually exporting it now though,
585 	     * the child can do it at the last minute.
586 	     */
587 	    return 1;
588 	}
589 	n = snprintf(tmp, sizeof(tmp), "${%s}", name);
590 	if (n < sizeof(tmp)) {
591 	    val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
592 	    setenv(name, val, 1);
593 	    free(val);
594 	}
595     } else {
596 	v->flags &= ~VAR_REEXPORT;	/* once will do */
597 	if (force || !(v->flags & VAR_EXPORTED)) {
598 	    setenv(name, val, 1);
599 	}
600     }
601     /*
602      * This is so Var_Set knows to call Var_Export again...
603      */
604     v->flags |= VAR_EXPORTED;
605     return 1;
606 }
607 
608 /*
609  * This gets called from our children.
610  */
611 void
612 Var_ExportVars(void)
613 {
614     char tmp[BUFSIZ];
615     Hash_Entry         	*var;
616     Hash_Search 	state;
617     Var *v;
618     char *val;
619     int n;
620 
621     if (VAR_EXPORTED_NONE == var_exportedVars)
622 	return;
623 
624     if (VAR_EXPORTED_ALL == var_exportedVars) {
625 	/*
626 	 * Ouch! This is crazy...
627 	 */
628 	for (var = Hash_EnumFirst(&VAR_GLOBAL->context, &state);
629 	     var != NULL;
630 	     var = Hash_EnumNext(&state)) {
631 	    v = (Var *)Hash_GetValue(var);
632 	    Var_Export1(v->name, 0);
633 	}
634 	return;
635     }
636     /*
637      * We have a number of exported vars,
638      */
639     n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
640     if (n < sizeof(tmp)) {
641 	char **av;
642 	char *as;
643 	int ac;
644 	int i;
645 
646 	val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
647 	av = brk_string(val, &ac, FALSE, &as);
648 	for (i = 0; i < ac; i++) {
649 	    Var_Export1(av[i], 0);
650 	}
651 	free(val);
652 	free(as);
653 	free(av);
654     }
655 }
656 
657 /*
658  * This is called when .export is seen or
659  * .MAKE.EXPORTED is modified.
660  * It is also called when any exported var is modified.
661  */
662 void
663 Var_Export(char *str, int isExport)
664 {
665     char *name;
666     char *val;
667     char **av;
668     char *as;
669     int ac;
670     int i;
671 
672     if (isExport && (!str || !str[0])) {
673 	var_exportedVars = VAR_EXPORTED_ALL; /* use with caution! */
674 	return;
675     }
676 
677     val = Var_Subst(NULL, str, VAR_GLOBAL, 0);
678     av = brk_string(val, &ac, FALSE, &as);
679     for (i = 0; i < ac; i++) {
680 	name = av[i];
681 	if (!name[1]) {
682 	    /*
683 	     * A single char.
684 	     * If it is one of the vars that should only appear in
685 	     * local context, skip it, else we can get Var_Subst
686 	     * into a loop.
687 	     */
688 	    switch (name[0]) {
689 	    case '@':
690 	    case '%':
691 	    case '*':
692 	    case '!':
693 		continue;
694 	    }
695 	}
696 	if (Var_Export1(name, VAR_EXPORT_FORCE)) {
697 	    if (VAR_EXPORTED_ALL != var_exportedVars)
698 		var_exportedVars = VAR_EXPORTED_YES;
699 	    if (isExport) {
700 		Var_Append(MAKE_EXPORTED, name, VAR_GLOBAL);
701 	    }
702 	}
703     }
704     free(val);
705     free(as);
706     free(av);
707 }
708 
709 /*-
710  *-----------------------------------------------------------------------
711  * Var_Set --
712  *	Set the variable name to the value val in the given context.
713  *
714  * Input:
715  *	name		name of variable to set
716  *	val		value to give to the variable
717  *	ctxt		context in which to set it
718  *
719  * Results:
720  *	None.
721  *
722  * Side Effects:
723  *	If the variable doesn't yet exist, a new record is created for it.
724  *	Else the old value is freed and the new one stuck in its place
725  *
726  * Notes:
727  *	The variable is searched for only in its context before being
728  *	created in that context. I.e. if the context is VAR_GLOBAL,
729  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
730  *	VAR_CMD->context is searched. This is done to avoid the literally
731  *	thousands of unnecessary strcmp's that used to be done to
732  *	set, say, $(@) or $(<).
733  *	If the context is VAR_GLOBAL though, we check if the variable
734  *	was set in VAR_CMD from the command line and skip it if so.
735  *-----------------------------------------------------------------------
736  */
737 void
738 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
739 {
740     Var   *v;
741     const char *cp = name;
742 
743     /*
744      * We only look for a variable in the given context since anything set
745      * here will override anything in a lower context, so there's not much
746      * point in searching them all just to save a bit of memory...
747      */
748     if ((name = strchr(cp, '$'))) {
749 	name = Var_Subst(NULL, cp, ctxt, 0);
750     } else
751 	name = cp;
752     if (ctxt == VAR_GLOBAL) {
753 	v = VarFind(name, VAR_CMD, 0);
754 	if (v != (Var *)NIL) {
755 	    if ((v->flags & VAR_FROM_CMD)) {
756 		if (DEBUG(VAR)) {
757 		    fprintf(debug_file, "%s:%s = %s ignored!\n", ctxt->name, name, val);
758 		}
759 		goto out;
760 	    }
761 	    VarFreeEnv(v, TRUE);
762 	}
763     }
764     v = VarFind(name, ctxt, 0);
765     if (v == (Var *)NIL) {
766 	VarAdd(name, val, ctxt);
767     } else {
768 	Buf_Discard(v->val, Buf_Size(v->val));
769 	Buf_AddBytes(v->val, strlen(val), (const Byte *)val);
770 
771 	if (DEBUG(VAR)) {
772 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
773 	}
774 	if ((v->flags & VAR_EXPORTED)) {
775 	    Var_Export1(name, VAR_EXPORT_FORCE);
776 	}
777     }
778     /*
779      * Any variables given on the command line are automatically exported
780      * to the environment (as per POSIX standard)
781      */
782     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
783 	if (v == (Var *)NIL) {
784 	    /* we just added it */
785 	    v = VarFind(name, ctxt, 0);
786 	}
787 	v->flags |= VAR_FROM_CMD;
788 	/*
789 	 * If requested, don't export these in the environment
790 	 * individually.  We still put them in MAKEOVERRIDES so
791 	 * that the command-line settings continue to override
792 	 * Makefile settings.
793 	 */
794 	if (varNoExportEnv != TRUE)
795 	    setenv(name, val, 1);
796 
797 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
798     }
799  out:
800     if (name != cp)
801 	free(UNCONST(name));
802     if (v != (Var *)NIL)
803 	VarFreeEnv(v, TRUE);
804 }
805 
806 /*-
807  *-----------------------------------------------------------------------
808  * Var_Append --
809  *	The variable of the given name has the given value appended to it in
810  *	the given context.
811  *
812  * Input:
813  *	name		name of variable to modify
814  *	val		String to append to it
815  *	ctxt		Context in which this should occur
816  *
817  * Results:
818  *	None
819  *
820  * Side Effects:
821  *	If the variable doesn't exist, it is created. Else the strings
822  *	are concatenated (with a space in between).
823  *
824  * Notes:
825  *	Only if the variable is being sought in the global context is the
826  *	environment searched.
827  *	XXX: Knows its calling circumstances in that if called with ctxt
828  *	an actual target, it will only search that context since only
829  *	a local variable could be being appended to. This is actually
830  *	a big win and must be tolerated.
831  *-----------------------------------------------------------------------
832  */
833 void
834 Var_Append(const char *name, const char *val, GNode *ctxt)
835 {
836     Var		   *v;
837     Hash_Entry	   *h;
838     const char *cp = name;
839 
840     if ((name = strchr(cp, '$'))) {
841 	name = Var_Subst(NULL, cp, ctxt, 0);
842     } else
843 	name = cp;
844 
845     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
846 
847     if (v == (Var *)NIL) {
848 	VarAdd(name, val, ctxt);
849     } else {
850 	Buf_AddByte(v->val, (Byte)' ');
851 	Buf_AddBytes(v->val, strlen(val), (const Byte *)val);
852 
853 	if (DEBUG(VAR)) {
854 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name,
855 		   (char *)Buf_GetAll(v->val, NULL));
856 	}
857 
858 	if (v->flags & VAR_FROM_ENV) {
859 	    /*
860 	     * If the original variable came from the environment, we
861 	     * have to install it in the global context (we could place
862 	     * it in the environment, but then we should provide a way to
863 	     * export other variables...)
864 	     */
865 	    v->flags &= ~VAR_FROM_ENV;
866 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
867 	    Hash_SetValue(h, v);
868 	}
869     }
870     if (name != cp)
871 	free(UNCONST(name));
872 }
873 
874 /*-
875  *-----------------------------------------------------------------------
876  * Var_Exists --
877  *	See if the given variable exists.
878  *
879  * Input:
880  *	name		Variable to find
881  *	ctxt		Context in which to start search
882  *
883  * Results:
884  *	TRUE if it does, FALSE if it doesn't
885  *
886  * Side Effects:
887  *	None.
888  *
889  *-----------------------------------------------------------------------
890  */
891 Boolean
892 Var_Exists(const char *name, GNode *ctxt)
893 {
894     Var	    	  *v;
895     char          *cp;
896 
897     if ((cp = strchr(name, '$')) != NULL) {
898 	cp = Var_Subst(NULL, name, ctxt, FALSE);
899     }
900     v = VarFind(cp ? cp : name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
901     if (cp != NULL) {
902 	free(cp);
903     }
904     if (v == (Var *)NIL) {
905 	return(FALSE);
906     } else {
907 	(void)VarFreeEnv(v, TRUE);
908     }
909     return(TRUE);
910 }
911 
912 /*-
913  *-----------------------------------------------------------------------
914  * Var_Value --
915  *	Return the value of the named variable in the given context
916  *
917  * Input:
918  *	name		name to find
919  *	ctxt		context in which to search for it
920  *
921  * Results:
922  *	The value if the variable exists, NULL if it doesn't
923  *
924  * Side Effects:
925  *	None
926  *-----------------------------------------------------------------------
927  */
928 char *
929 Var_Value(const char *name, GNode *ctxt, char **frp)
930 {
931     Var            *v;
932 
933     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
934     *frp = NULL;
935     if (v != (Var *)NIL) {
936 	char *p = ((char *)Buf_GetAll(v->val, NULL));
937 	if (VarFreeEnv(v, FALSE))
938 	    *frp = p;
939 	return p;
940     } else {
941 	return (NULL);
942     }
943 }
944 
945 /*-
946  *-----------------------------------------------------------------------
947  * VarHead --
948  *	Remove the tail of the given word and place the result in the given
949  *	buffer.
950  *
951  * Input:
952  *	word		Word to trim
953  *	addSpace	True if need to add a space to the buffer
954  *			before sticking in the head
955  *	buf		Buffer in which to store it
956  *
957  * Results:
958  *	TRUE if characters were added to the buffer (a space needs to be
959  *	added to the buffer before the next word).
960  *
961  * Side Effects:
962  *	The trimmed word is added to the buffer.
963  *
964  *-----------------------------------------------------------------------
965  */
966 static Boolean
967 VarHead(GNode *ctx __unused, Var_Parse_State *vpstate,
968 	char *word, Boolean addSpace, Buffer buf,
969 	ClientData dummy)
970 {
971     char *slash;
972 
973     slash = strrchr(word, '/');
974     if (slash != NULL) {
975 	if (addSpace && vpstate->varSpace) {
976 	    Buf_AddByte(buf, vpstate->varSpace);
977 	}
978 	*slash = '\0';
979 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
980 	*slash = '/';
981 	return (TRUE);
982     } else {
983 	/*
984 	 * If no directory part, give . (q.v. the POSIX standard)
985 	 */
986 	if (addSpace && vpstate->varSpace)
987 	    Buf_AddByte(buf, vpstate->varSpace);
988 	Buf_AddByte(buf, (Byte)'.');
989     }
990     return(dummy ? TRUE : TRUE);
991 }
992 
993 /*-
994  *-----------------------------------------------------------------------
995  * VarTail --
996  *	Remove the head of the given word and place the result in the given
997  *	buffer.
998  *
999  * Input:
1000  *	word		Word to trim
1001  *	addSpace	True if need to add a space to the buffer
1002  *			before adding the tail
1003  *	buf		Buffer in which to store it
1004  *
1005  * Results:
1006  *	TRUE if characters were added to the buffer (a space needs to be
1007  *	added to the buffer before the next word).
1008  *
1009  * Side Effects:
1010  *	The trimmed word is added to the buffer.
1011  *
1012  *-----------------------------------------------------------------------
1013  */
1014 static Boolean
1015 VarTail(GNode *ctx __unused, Var_Parse_State *vpstate,
1016 	char *word, Boolean addSpace, Buffer buf,
1017 	ClientData dummy)
1018 {
1019     char *slash;
1020 
1021     if (addSpace && vpstate->varSpace) {
1022 	Buf_AddByte(buf, vpstate->varSpace);
1023     }
1024 
1025     slash = strrchr(word, '/');
1026     if (slash != NULL) {
1027 	*slash++ = '\0';
1028 	Buf_AddBytes(buf, strlen(slash), (Byte *)slash);
1029 	slash[-1] = '/';
1030     } else {
1031 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1032     }
1033     return (dummy ? TRUE : TRUE);
1034 }
1035 
1036 /*-
1037  *-----------------------------------------------------------------------
1038  * VarSuffix --
1039  *	Place the suffix of the given word in the given buffer.
1040  *
1041  * Input:
1042  *	word		Word to trim
1043  *	addSpace	TRUE if need to add a space before placing the
1044  *			suffix in the buffer
1045  *	buf		Buffer in which to store it
1046  *
1047  * Results:
1048  *	TRUE if characters were added to the buffer (a space needs to be
1049  *	added to the buffer before the next word).
1050  *
1051  * Side Effects:
1052  *	The suffix from the word is placed in the buffer.
1053  *
1054  *-----------------------------------------------------------------------
1055  */
1056 static Boolean
1057 VarSuffix(GNode *ctx __unused, Var_Parse_State *vpstate,
1058 	  char *word, Boolean addSpace, Buffer buf,
1059 	  ClientData dummy)
1060 {
1061     char *dot;
1062 
1063     dot = strrchr(word, '.');
1064     if (dot != NULL) {
1065 	if (addSpace && vpstate->varSpace) {
1066 	    Buf_AddByte(buf, vpstate->varSpace);
1067 	}
1068 	*dot++ = '\0';
1069 	Buf_AddBytes(buf, strlen(dot), (Byte *)dot);
1070 	dot[-1] = '.';
1071 	addSpace = TRUE;
1072     }
1073     return (dummy ? addSpace : addSpace);
1074 }
1075 
1076 /*-
1077  *-----------------------------------------------------------------------
1078  * VarRoot --
1079  *	Remove the suffix of the given word and place the result in the
1080  *	buffer.
1081  *
1082  * Input:
1083  *	word		Word to trim
1084  *	addSpace	TRUE if need to add a space to the buffer
1085  *			before placing the root in it
1086  *	buf		Buffer in which to store it
1087  *
1088  * Results:
1089  *	TRUE if characters were added to the buffer (a space needs to be
1090  *	added to the buffer before the next word).
1091  *
1092  * Side Effects:
1093  *	The trimmed word is added to the buffer.
1094  *
1095  *-----------------------------------------------------------------------
1096  */
1097 static Boolean
1098 VarRoot(GNode *ctx __unused, Var_Parse_State *vpstate,
1099 	char *word, Boolean addSpace, Buffer buf,
1100 	ClientData dummy)
1101 {
1102     char *dot;
1103 
1104     if (addSpace && vpstate->varSpace) {
1105 	Buf_AddByte(buf, vpstate->varSpace);
1106     }
1107 
1108     dot = strrchr(word, '.');
1109     if (dot != NULL) {
1110 	*dot = '\0';
1111 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1112 	*dot = '.';
1113     } else {
1114 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1115     }
1116     return (dummy ? TRUE : TRUE);
1117 }
1118 
1119 /*-
1120  *-----------------------------------------------------------------------
1121  * VarMatch --
1122  *	Place the word in the buffer if it matches the given pattern.
1123  *	Callback function for VarModify to implement the :M modifier.
1124  *
1125  * Input:
1126  *	word		Word to examine
1127  *	addSpace	TRUE if need to add a space to the buffer
1128  *			before adding the word, if it matches
1129  *	buf		Buffer in which to store it
1130  *	pattern		Pattern the word must match
1131  *
1132  * Results:
1133  *	TRUE if a space should be placed in the buffer before the next
1134  *	word.
1135  *
1136  * Side Effects:
1137  *	The word may be copied to the buffer.
1138  *
1139  *-----------------------------------------------------------------------
1140  */
1141 static Boolean
1142 VarMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
1143 	 char *word, Boolean addSpace, Buffer buf,
1144 	 ClientData pattern)
1145 {
1146     if (Str_Match(word, (char *)pattern)) {
1147 	if (addSpace && vpstate->varSpace) {
1148 	    Buf_AddByte(buf, vpstate->varSpace);
1149 	}
1150 	addSpace = TRUE;
1151 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1152     }
1153     return(addSpace);
1154 }
1155 
1156 #ifdef SYSVVARSUB
1157 /*-
1158  *-----------------------------------------------------------------------
1159  * VarSYSVMatch --
1160  *	Place the word in the buffer if it matches the given pattern.
1161  *	Callback function for VarModify to implement the System V %
1162  *	modifiers.
1163  *
1164  * Input:
1165  *	word		Word to examine
1166  *	addSpace	TRUE if need to add a space to the buffer
1167  *			before adding the word, if it matches
1168  *	buf		Buffer in which to store it
1169  *	patp		Pattern the word must match
1170  *
1171  * Results:
1172  *	TRUE if a space should be placed in the buffer before the next
1173  *	word.
1174  *
1175  * Side Effects:
1176  *	The word may be copied to the buffer.
1177  *
1178  *-----------------------------------------------------------------------
1179  */
1180 static Boolean
1181 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
1182 	     char *word, Boolean addSpace, Buffer buf,
1183 	     ClientData patp)
1184 {
1185     int len;
1186     char *ptr;
1187     VarPattern 	  *pat = (VarPattern *)patp;
1188     char *varexp;
1189 
1190     if (addSpace && vpstate->varSpace)
1191 	Buf_AddByte(buf, vpstate->varSpace);
1192 
1193     addSpace = TRUE;
1194 
1195     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
1196         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
1197 	Str_SYSVSubst(buf, varexp, ptr, len);
1198 	free(varexp);
1199     } else {
1200 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1201     }
1202 
1203     return(addSpace);
1204 }
1205 #endif
1206 
1207 
1208 /*-
1209  *-----------------------------------------------------------------------
1210  * VarNoMatch --
1211  *	Place the word in the buffer if it doesn't match the given pattern.
1212  *	Callback function for VarModify to implement the :N modifier.
1213  *
1214  * Input:
1215  *	word		Word to examine
1216  *	addSpace	TRUE if need to add a space to the buffer
1217  *			before adding the word, if it matches
1218  *	buf		Buffer in which to store it
1219  *	pattern		Pattern the word must match
1220  *
1221  * Results:
1222  *	TRUE if a space should be placed in the buffer before the next
1223  *	word.
1224  *
1225  * Side Effects:
1226  *	The word may be copied to the buffer.
1227  *
1228  *-----------------------------------------------------------------------
1229  */
1230 static Boolean
1231 VarNoMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
1232 	   char *word, Boolean addSpace, Buffer buf,
1233 	   ClientData pattern)
1234 {
1235     if (!Str_Match(word, (char *)pattern)) {
1236 	if (addSpace && vpstate->varSpace) {
1237 	    Buf_AddByte(buf, vpstate->varSpace);
1238 	}
1239 	addSpace = TRUE;
1240 	Buf_AddBytes(buf, strlen(word), (Byte *)word);
1241     }
1242     return(addSpace);
1243 }
1244 
1245 
1246 /*-
1247  *-----------------------------------------------------------------------
1248  * VarSubstitute --
1249  *	Perform a string-substitution on the given word, placing the
1250  *	result in the passed buffer.
1251  *
1252  * Input:
1253  *	word		Word to modify
1254  *	addSpace	True if space should be added before
1255  *			other characters
1256  *	buf		Buffer for result
1257  *	patternp	Pattern for substitution
1258  *
1259  * Results:
1260  *	TRUE if a space is needed before more characters are added.
1261  *
1262  * Side Effects:
1263  *	None.
1264  *
1265  *-----------------------------------------------------------------------
1266  */
1267 static Boolean
1268 VarSubstitute(GNode *ctx __unused, Var_Parse_State *vpstate,
1269 	      char *word, Boolean addSpace, Buffer buf,
1270 	      ClientData patternp)
1271 {
1272     int  	wordLen;    /* Length of word */
1273     char 	*cp;	    /* General pointer */
1274     VarPattern	*pattern = (VarPattern *)patternp;
1275 
1276     wordLen = strlen(word);
1277     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
1278 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
1279 	/*
1280 	 * Still substituting -- break it down into simple anchored cases
1281 	 * and if none of them fits, perform the general substitution case.
1282 	 */
1283 	if ((pattern->flags & VAR_MATCH_START) &&
1284 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
1285 		/*
1286 		 * Anchored at start and beginning of word matches pattern
1287 		 */
1288 		if ((pattern->flags & VAR_MATCH_END) &&
1289 		    (wordLen == pattern->leftLen)) {
1290 			/*
1291 			 * Also anchored at end and matches to the end (word
1292 			 * is same length as pattern) add space and rhs only
1293 			 * if rhs is non-null.
1294 			 */
1295 			if (pattern->rightLen != 0) {
1296 			    if (addSpace && vpstate->varSpace) {
1297 				Buf_AddByte(buf, vpstate->varSpace);
1298 			    }
1299 			    addSpace = TRUE;
1300 			    Buf_AddBytes(buf, pattern->rightLen,
1301 					 (const Byte *)pattern->rhs);
1302 			}
1303 			pattern->flags |= VAR_SUB_MATCHED;
1304 		} else if (pattern->flags & VAR_MATCH_END) {
1305 		    /*
1306 		     * Doesn't match to end -- copy word wholesale
1307 		     */
1308 		    goto nosub;
1309 		} else {
1310 		    /*
1311 		     * Matches at start but need to copy in trailing characters
1312 		     */
1313 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
1314 			if (addSpace && vpstate->varSpace) {
1315 			    Buf_AddByte(buf, vpstate->varSpace);
1316 			}
1317 			addSpace = TRUE;
1318 		    }
1319 		    Buf_AddBytes(buf, pattern->rightLen,
1320 			(const Byte *)pattern->rhs);
1321 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
1322 				 (Byte *)(word + pattern->leftLen));
1323 		    pattern->flags |= VAR_SUB_MATCHED;
1324 		}
1325 	} else if (pattern->flags & VAR_MATCH_START) {
1326 	    /*
1327 	     * Had to match at start of word and didn't -- copy whole word.
1328 	     */
1329 	    goto nosub;
1330 	} else if (pattern->flags & VAR_MATCH_END) {
1331 	    /*
1332 	     * Anchored at end, Find only place match could occur (leftLen
1333 	     * characters from the end of the word) and see if it does. Note
1334 	     * that because the $ will be left at the end of the lhs, we have
1335 	     * to use strncmp.
1336 	     */
1337 	    cp = word + (wordLen - pattern->leftLen);
1338 	    if ((cp >= word) &&
1339 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
1340 		/*
1341 		 * Match found. If we will place characters in the buffer,
1342 		 * add a space before hand as indicated by addSpace, then
1343 		 * stuff in the initial, unmatched part of the word followed
1344 		 * by the right-hand-side.
1345 		 */
1346 		if (((cp - word) + pattern->rightLen) != 0) {
1347 		    if (addSpace && vpstate->varSpace) {
1348 			Buf_AddByte(buf, vpstate->varSpace);
1349 		    }
1350 		    addSpace = TRUE;
1351 		}
1352 		Buf_AddBytes(buf, cp - word, (const Byte *)word);
1353 		Buf_AddBytes(buf, pattern->rightLen,
1354 		    (const Byte *)pattern->rhs);
1355 		pattern->flags |= VAR_SUB_MATCHED;
1356 	    } else {
1357 		/*
1358 		 * Had to match at end and didn't. Copy entire word.
1359 		 */
1360 		goto nosub;
1361 	    }
1362 	} else {
1363 	    /*
1364 	     * Pattern is unanchored: search for the pattern in the word using
1365 	     * String_FindSubstring, copying unmatched portions and the
1366 	     * right-hand-side for each match found, handling non-global
1367 	     * substitutions correctly, etc. When the loop is done, any
1368 	     * remaining part of the word (word and wordLen are adjusted
1369 	     * accordingly through the loop) is copied straight into the
1370 	     * buffer.
1371 	     * addSpace is set FALSE as soon as a space is added to the
1372 	     * buffer.
1373 	     */
1374 	    Boolean done;
1375 	    int origSize;
1376 
1377 	    done = FALSE;
1378 	    origSize = Buf_Size(buf);
1379 	    while (!done) {
1380 		cp = Str_FindSubstring(word, pattern->lhs);
1381 		if (cp != NULL) {
1382 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
1383 			Buf_AddByte(buf, vpstate->varSpace);
1384 			addSpace = FALSE;
1385 		    }
1386 		    Buf_AddBytes(buf, cp-word, (const Byte *)word);
1387 		    Buf_AddBytes(buf, pattern->rightLen,
1388 			(const Byte *)pattern->rhs);
1389 		    wordLen -= (cp - word) + pattern->leftLen;
1390 		    word = cp + pattern->leftLen;
1391 		    if (wordLen == 0) {
1392 			done = TRUE;
1393 		    }
1394 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
1395 			done = TRUE;
1396 		    }
1397 		    pattern->flags |= VAR_SUB_MATCHED;
1398 		} else {
1399 		    done = TRUE;
1400 		}
1401 	    }
1402 	    if (wordLen != 0) {
1403 		if (addSpace && vpstate->varSpace) {
1404 		    Buf_AddByte(buf, vpstate->varSpace);
1405 		}
1406 		Buf_AddBytes(buf, wordLen, (Byte *)word);
1407 	    }
1408 	    /*
1409 	     * If added characters to the buffer, need to add a space
1410 	     * before we add any more. If we didn't add any, just return
1411 	     * the previous value of addSpace.
1412 	     */
1413 	    return ((Buf_Size(buf) != origSize) || addSpace);
1414 	}
1415 	return (addSpace);
1416     }
1417  nosub:
1418     if (addSpace && vpstate->varSpace) {
1419 	Buf_AddByte(buf, vpstate->varSpace);
1420     }
1421     Buf_AddBytes(buf, wordLen, (Byte *)word);
1422     return(TRUE);
1423 }
1424 
1425 #ifndef NO_REGEX
1426 /*-
1427  *-----------------------------------------------------------------------
1428  * VarREError --
1429  *	Print the error caused by a regcomp or regexec call.
1430  *
1431  * Results:
1432  *	None.
1433  *
1434  * Side Effects:
1435  *	An error gets printed.
1436  *
1437  *-----------------------------------------------------------------------
1438  */
1439 static void
1440 VarREError(int errnum, regex_t *pat, const char *str)
1441 {
1442     char *errbuf;
1443     int errlen;
1444 
1445     errlen = regerror(errnum, pat, 0, 0);
1446     errbuf = emalloc(errlen);
1447     regerror(errnum, pat, errbuf, errlen);
1448     Error("%s: %s", str, errbuf);
1449     free(errbuf);
1450 }
1451 
1452 
1453 /*-
1454  *-----------------------------------------------------------------------
1455  * VarRESubstitute --
1456  *	Perform a regex substitution on the given word, placing the
1457  *	result in the passed buffer.
1458  *
1459  * Results:
1460  *	TRUE if a space is needed before more characters are added.
1461  *
1462  * Side Effects:
1463  *	None.
1464  *
1465  *-----------------------------------------------------------------------
1466  */
1467 static Boolean
1468 VarRESubstitute(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
1469 		char *word, Boolean addSpace, Buffer buf,
1470 		ClientData patternp)
1471 {
1472     VarREPattern *pat;
1473     int xrv;
1474     char *wp;
1475     char *rp;
1476     int added;
1477     int flags = 0;
1478 
1479 #define MAYBE_ADD_SPACE()		\
1480 	if (addSpace && !added)		\
1481 	    Buf_AddByte(buf, ' ');	\
1482 	added = 1
1483 
1484     added = 0;
1485     wp = word;
1486     pat = patternp;
1487 
1488     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
1489 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
1490 	xrv = REG_NOMATCH;
1491     else {
1492     tryagain:
1493 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
1494     }
1495 
1496     switch (xrv) {
1497     case 0:
1498 	pat->flags |= VAR_SUB_MATCHED;
1499 	if (pat->matches[0].rm_so > 0) {
1500 	    MAYBE_ADD_SPACE();
1501 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
1502 	}
1503 
1504 	for (rp = pat->replace; *rp; rp++) {
1505 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
1506 		MAYBE_ADD_SPACE();
1507 		Buf_AddByte(buf,rp[1]);
1508 		rp++;
1509 	    }
1510 	    else if ((*rp == '&') ||
1511 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
1512 		int n;
1513 		const char *subbuf;
1514 		int sublen;
1515 		char errstr[3];
1516 
1517 		if (*rp == '&') {
1518 		    n = 0;
1519 		    errstr[0] = '&';
1520 		    errstr[1] = '\0';
1521 		} else {
1522 		    n = rp[1] - '0';
1523 		    errstr[0] = '\\';
1524 		    errstr[1] = rp[1];
1525 		    errstr[2] = '\0';
1526 		    rp++;
1527 		}
1528 
1529 		if (n > pat->nsub) {
1530 		    Error("No subexpression %s", &errstr[0]);
1531 		    subbuf = "";
1532 		    sublen = 0;
1533 		} else if ((pat->matches[n].rm_so == -1) &&
1534 			   (pat->matches[n].rm_eo == -1)) {
1535 		    Error("No match for subexpression %s", &errstr[0]);
1536 		    subbuf = "";
1537 		    sublen = 0;
1538 	        } else {
1539 		    subbuf = wp + pat->matches[n].rm_so;
1540 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
1541 		}
1542 
1543 		if (sublen > 0) {
1544 		    MAYBE_ADD_SPACE();
1545 		    Buf_AddBytes(buf, sublen, subbuf);
1546 		}
1547 	    } else {
1548 		MAYBE_ADD_SPACE();
1549 		Buf_AddByte(buf, *rp);
1550 	    }
1551 	}
1552 	wp += pat->matches[0].rm_eo;
1553 	if (pat->flags & VAR_SUB_GLOBAL) {
1554 	    flags |= REG_NOTBOL;
1555 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
1556 		MAYBE_ADD_SPACE();
1557 		Buf_AddByte(buf, *wp);
1558 		wp++;
1559 
1560 	    }
1561 	    if (*wp)
1562 		goto tryagain;
1563 	}
1564 	if (*wp) {
1565 	    MAYBE_ADD_SPACE();
1566 	    Buf_AddBytes(buf, strlen(wp), wp);
1567 	}
1568 	break;
1569     default:
1570 	VarREError(xrv, &pat->re, "Unexpected regex error");
1571        /* fall through */
1572     case REG_NOMATCH:
1573 	if (*wp) {
1574 	    MAYBE_ADD_SPACE();
1575 	    Buf_AddBytes(buf,strlen(wp),wp);
1576 	}
1577 	break;
1578     }
1579     return(addSpace||added);
1580 }
1581 #endif
1582 
1583 
1584 
1585 /*-
1586  *-----------------------------------------------------------------------
1587  * VarLoopExpand --
1588  *	Implements the :@<temp>@<string>@ modifier of ODE make.
1589  *	We set the temp variable named in pattern.lhs to word and expand
1590  *	pattern.rhs storing the result in the passed buffer.
1591  *
1592  * Input:
1593  *	word		Word to modify
1594  *	addSpace	True if space should be added before
1595  *			other characters
1596  *	buf		Buffer for result
1597  *	pattern		Datafor substitution
1598  *
1599  * Results:
1600  *	TRUE if a space is needed before more characters are added.
1601  *
1602  * Side Effects:
1603  *	None.
1604  *
1605  *-----------------------------------------------------------------------
1606  */
1607 static Boolean
1608 VarLoopExpand(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
1609 	      char *word, Boolean addSpace, Buffer buf,
1610 	      ClientData loopp)
1611 {
1612     VarLoop_t	*loop = (VarLoop_t *)loopp;
1613     char *s;
1614     int slen;
1615 
1616     if (word && *word) {
1617         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
1618         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->errnum);
1619         if (s != NULL && *s != '\0') {
1620             if (addSpace && *s != '\n')
1621                 Buf_AddByte(buf, ' ');
1622             Buf_AddBytes(buf, (slen = strlen(s)), (Byte *)s);
1623             addSpace = (slen > 0 && s[slen - 1] != '\n');
1624             free(s);
1625         }
1626     }
1627     return addSpace;
1628 }
1629 
1630 
1631 /*-
1632  *-----------------------------------------------------------------------
1633  * VarSelectWords --
1634  *	Implements the :[start..end] modifier.
1635  *	This is a special case of VarModify since we want to be able
1636  *	to scan the list backwards if start > end.
1637  *
1638  * Input:
1639  *	str		String whose words should be trimmed
1640  *	seldata		words to select
1641  *
1642  * Results:
1643  *	A string of all the words selected.
1644  *
1645  * Side Effects:
1646  *	None.
1647  *
1648  *-----------------------------------------------------------------------
1649  */
1650 static char *
1651 VarSelectWords(GNode *ctx __unused, Var_Parse_State *vpstate,
1652 	       const char *str, VarSelectWords_t *seldata)
1653 {
1654     Buffer  	  buf;	    	    /* Buffer for the new string */
1655     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1656 				     * buffer before adding the trimmed
1657 				     * word */
1658     char **av;			    /* word list */
1659     char *as;			    /* word list memory */
1660     int ac, i;
1661     int start, end, step;
1662 
1663     buf = Buf_Init(0);
1664     addSpace = FALSE;
1665 
1666     if (vpstate->oneBigWord) {
1667 	/* fake what brk_string() would do if there were only one word */
1668 	ac = 1;
1669     	av = emalloc((ac + 1) * sizeof(char *));
1670 	as = estrdup(str);
1671 	av[0] = as;
1672 	av[1] = NULL;
1673     } else {
1674 	av = brk_string(str, &ac, FALSE, &as);
1675     }
1676 
1677     /*
1678      * Now sanitize seldata.
1679      * If seldata->start or seldata->end are negative, convert them to
1680      * the positive equivalents (-1 gets converted to argc, -2 gets
1681      * converted to (argc-1), etc.).
1682      */
1683     if (seldata->start < 0)
1684 	seldata->start = ac + seldata->start + 1;
1685     if (seldata->end < 0)
1686 	seldata->end = ac + seldata->end + 1;
1687 
1688     /*
1689      * We avoid scanning more of the list than we need to.
1690      */
1691     if (seldata->start > seldata->end) {
1692 	start = MIN(ac, seldata->start) - 1;
1693 	end = MAX(0, seldata->end - 1);
1694 	step = -1;
1695     } else {
1696 	start = MAX(0, seldata->start - 1);
1697 	end = MIN(ac, seldata->end);
1698 	step = 1;
1699     }
1700 
1701     for (i = start;
1702 	 (step < 0 && i >= end) || (step > 0 && i < end);
1703 	 i += step) {
1704 	if (av[i] && *av[i]) {
1705 	    if (addSpace && vpstate->varSpace) {
1706 		Buf_AddByte(buf, vpstate->varSpace);
1707 	    }
1708 	    Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1709 	    addSpace = TRUE;
1710 	}
1711     }
1712 
1713     free(as);
1714     free(av);
1715 
1716     Buf_AddByte(buf, '\0');
1717     as = (char *)Buf_GetAll(buf, NULL);
1718     Buf_Destroy(buf, FALSE);
1719     return (as);
1720 }
1721 
1722 /*-
1723  *-----------------------------------------------------------------------
1724  * VarModify --
1725  *	Modify each of the words of the passed string using the given
1726  *	function. Used to implement all modifiers.
1727  *
1728  * Input:
1729  *	str		String whose words should be trimmed
1730  *	modProc		Function to use to modify them
1731  *	datum		Datum to pass it
1732  *
1733  * Results:
1734  *	A string of all the words modified appropriately.
1735  *
1736  * Side Effects:
1737  *	None.
1738  *
1739  *-----------------------------------------------------------------------
1740  */
1741 static char *
1742 VarModify(GNode *ctx, Var_Parse_State *vpstate,
1743     const char *str,
1744     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
1745 		       Boolean, Buffer, ClientData),
1746     ClientData datum)
1747 {
1748     Buffer  	  buf;	    	    /* Buffer for the new string */
1749     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
1750 				     * buffer before adding the trimmed
1751 				     * word */
1752     char **av;			    /* word list */
1753     char *as;			    /* word list memory */
1754     int ac, i;
1755 
1756     buf = Buf_Init(0);
1757     addSpace = FALSE;
1758 
1759     if (vpstate->oneBigWord) {
1760 	/* fake what brk_string() would do if there were only one word */
1761 	ac = 1;
1762     	av = emalloc((ac + 1) * sizeof(char *));
1763 	as = estrdup(str);
1764 	av[0] = as;
1765 	av[1] = NULL;
1766     } else {
1767 	av = brk_string(str, &ac, FALSE, &as);
1768     }
1769 
1770     for (i = 0; i < ac; i++) {
1771 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, buf, datum);
1772     }
1773 
1774     free(as);
1775     free(av);
1776 
1777     Buf_AddByte(buf, '\0');
1778     as = (char *)Buf_GetAll(buf, NULL);
1779     Buf_Destroy(buf, FALSE);
1780     return (as);
1781 }
1782 
1783 
1784 static int
1785 VarWordCompare(const void *a, const void *b)
1786 {
1787 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
1788 	return r;
1789 }
1790 
1791 /*-
1792  *-----------------------------------------------------------------------
1793  * VarOrder --
1794  *	Order the words in the string.
1795  *
1796  * Input:
1797  *	str		String whose words should be sorted.
1798  *	otype		How to order: s - sort, x - random.
1799  *
1800  * Results:
1801  *	A string containing the words ordered.
1802  *
1803  * Side Effects:
1804  *	None.
1805  *
1806  *-----------------------------------------------------------------------
1807  */
1808 static char *
1809 VarOrder(const char *str, const char otype)
1810 {
1811     Buffer  	  buf;	    	    /* Buffer for the new string */
1812     char **av;			    /* word list [first word does not count] */
1813     char *as;			    /* word list memory */
1814     int ac, i;
1815 
1816     buf = Buf_Init(0);
1817 
1818     av = brk_string(str, &ac, FALSE, &as);
1819 
1820     if (ac > 0)
1821 	switch (otype) {
1822 	case 's':	/* sort alphabetically */
1823 	    qsort(av, ac, sizeof(char *), VarWordCompare);
1824 	    break;
1825 	case 'x':	/* randomize */
1826 	{
1827 	    int rndidx;
1828 	    char *t;
1829 
1830 	    /*
1831 	     * We will use [ac..2] range for mod factors. This will produce
1832 	     * random numbers in [(ac-1)..0] interval, and minimal
1833 	     * reasonable value for mod factor is 2 (the mod 1 will produce
1834 	     * 0 with probability 1).
1835 	     */
1836 	    for (i = ac-1; i > 0; i--) {
1837 		rndidx = random() % (i + 1);
1838 		if (i != rndidx) {
1839 		    t = av[i];
1840 		    av[i] = av[rndidx];
1841 		    av[rndidx] = t;
1842 		}
1843 	    }
1844 	}
1845 	} /* end of switch */
1846 
1847     for (i = 0; i < ac; i++) {
1848 	Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1849 	if (i != ac - 1)
1850 	    Buf_AddByte(buf, ' ');
1851     }
1852 
1853     free(as);
1854     free(av);
1855 
1856     Buf_AddByte(buf, '\0');
1857     as = (char *)Buf_GetAll(buf, NULL);
1858     Buf_Destroy(buf, FALSE);
1859     return (as);
1860 }
1861 
1862 
1863 /*-
1864  *-----------------------------------------------------------------------
1865  * VarUniq --
1866  *	Remove adjacent duplicate words.
1867  *
1868  * Input:
1869  *	str		String whose words should be sorted
1870  *
1871  * Results:
1872  *	A string containing the resulting words.
1873  *
1874  * Side Effects:
1875  *	None.
1876  *
1877  *-----------------------------------------------------------------------
1878  */
1879 static char *
1880 VarUniq(const char *str)
1881 {
1882     Buffer	  buf;	    	    /* Buffer for new string */
1883     char 	**av;		    /* List of words to affect */
1884     char 	 *as;		    /* Word list memory */
1885     int 	  ac, i, j;
1886 
1887     buf = Buf_Init(0);
1888     av = brk_string(str, &ac, FALSE, &as);
1889 
1890     if (ac > 1) {
1891 	for (j = 0, i = 1; i < ac; i++)
1892 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
1893 		av[j] = av[i];
1894 	ac = j + 1;
1895     }
1896 
1897     for (i = 0; i < ac; i++) {
1898 	Buf_AddBytes(buf, strlen(av[i]), (Byte *)av[i]);
1899 	if (i != ac - 1)
1900 	    Buf_AddByte(buf, ' ');
1901     }
1902 
1903     free(as);
1904     free(av);
1905 
1906     Buf_AddByte(buf, '\0');
1907     as = (char *)Buf_GetAll(buf, NULL);
1908     Buf_Destroy(buf, FALSE);
1909     return as;
1910 }
1911 
1912 
1913 /*-
1914  *-----------------------------------------------------------------------
1915  * VarGetPattern --
1916  *	Pass through the tstr looking for 1) escaped delimiters,
1917  *	'$'s and backslashes (place the escaped character in
1918  *	uninterpreted) and 2) unescaped $'s that aren't before
1919  *	the delimiter (expand the variable substitution unless flags
1920  *	has VAR_NOSUBST set).
1921  *	Return the expanded string or NULL if the delimiter was missing
1922  *	If pattern is specified, handle escaped ampersands, and replace
1923  *	unescaped ampersands with the lhs of the pattern.
1924  *
1925  * Results:
1926  *	A string of all the words modified appropriately.
1927  *	If length is specified, return the string length of the buffer
1928  *	If flags is specified and the last character of the pattern is a
1929  *	$ set the VAR_MATCH_END bit of flags.
1930  *
1931  * Side Effects:
1932  *	None.
1933  *-----------------------------------------------------------------------
1934  */
1935 static char *
1936 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate __unused,
1937 	      int errnum, const char **tstr, int delim, int *flags,
1938 	      int *length, VarPattern *pattern)
1939 {
1940     const char *cp;
1941     Buffer buf = Buf_Init(0);
1942     int junk;
1943     if (length == NULL)
1944 	length = &junk;
1945 
1946 #define IS_A_MATCH(cp, delim) \
1947     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
1948      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
1949 
1950     /*
1951      * Skim through until the matching delimiter is found;
1952      * pick up variable substitutions on the way. Also allow
1953      * backslashes to quote the delimiter, $, and \, but don't
1954      * touch other backslashes.
1955      */
1956     for (cp = *tstr; *cp && (*cp != delim); cp++) {
1957 	if (IS_A_MATCH(cp, delim)) {
1958 	    Buf_AddByte(buf, (Byte)cp[1]);
1959 	    cp++;
1960 	} else if (*cp == '$') {
1961 	    if (cp[1] == delim) {
1962 		if (flags == NULL)
1963 		    Buf_AddByte(buf, (Byte)*cp);
1964 		else
1965 		    /*
1966 		     * Unescaped $ at end of pattern => anchor
1967 		     * pattern at end.
1968 		     */
1969 		    *flags |= VAR_MATCH_END;
1970 	    } else {
1971 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
1972 		    char   *cp2;
1973 		    int     len;
1974 		    void   *freeIt;
1975 
1976 		    /*
1977 		     * If unescaped dollar sign not before the
1978 		     * delimiter, assume it's a variable
1979 		     * substitution and recurse.
1980 		     */
1981 		    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
1982 		    Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
1983 		    if (freeIt)
1984 			free(freeIt);
1985 		    cp += len - 1;
1986 		} else {
1987 		    const char *cp2 = &cp[1];
1988 
1989 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
1990 			/*
1991 			 * Find the end of this variable reference
1992 			 * and suck it in without further ado.
1993 			 * It will be interperated later.
1994 			 */
1995 			int have = *cp2;
1996 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
1997 			int depth = 1;
1998 
1999 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
2000 			    if (cp2[-1] != '\\') {
2001 				if (*cp2 == have)
2002 				    ++depth;
2003 				if (*cp2 == want)
2004 				    --depth;
2005 			    }
2006 			}
2007 			Buf_AddBytes(buf, cp2 - cp, (const Byte *)cp);
2008 			cp = --cp2;
2009 		    } else
2010 			Buf_AddByte(buf, (Byte)*cp);
2011 		}
2012 	    }
2013 	}
2014 	else if (pattern && *cp == '&')
2015 	    Buf_AddBytes(buf, pattern->leftLen, (const Byte *)pattern->lhs);
2016 	else
2017 	    Buf_AddByte(buf, (Byte)*cp);
2018     }
2019 
2020     Buf_AddByte(buf, (Byte)'\0');
2021 
2022     if (*cp != delim) {
2023 	*tstr = cp;
2024 	*length = 0;
2025 	return NULL;
2026     }
2027     else {
2028 	char *rstr;
2029 	*tstr = ++cp;
2030 	rstr = (char *)Buf_GetAll(buf, length);
2031 	*length -= 1;	/* Don't count the NULL */
2032 	Buf_Destroy(buf, FALSE);
2033 	return rstr;
2034     }
2035 }
2036 
2037 /*-
2038  *-----------------------------------------------------------------------
2039  * VarQuote --
2040  *	Quote shell meta-characters in the string
2041  *
2042  * Results:
2043  *	The quoted string
2044  *
2045  * Side Effects:
2046  *	None.
2047  *
2048  *-----------------------------------------------------------------------
2049  */
2050 static char *
2051 VarQuote(char *str)
2052 {
2053 
2054     Buffer  	  buf;
2055     /* This should cover most shells :-( */
2056     static char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
2057     const char	*newline;
2058 
2059     newline = Shell_GetNewline();
2060 
2061     buf = Buf_Init(0);
2062     for (; *str; str++) {
2063 	if (*str == '\n' && newline != NULL) {
2064 	    Buf_AddBytes(buf, strlen(newline), newline);
2065 	} else {
2066 	    if (strchr(meta, *str) != NULL)
2067 		Buf_AddByte(buf, (Byte)'\\');
2068 	    Buf_AddByte(buf, (Byte)*str);
2069 	}
2070     }
2071     Buf_AddByte(buf, (Byte)'\0');
2072     str = (char *)Buf_GetAll(buf, NULL);
2073     Buf_Destroy(buf, FALSE);
2074     return str;
2075 }
2076 
2077 /*-
2078  *-----------------------------------------------------------------------
2079  * VarChangeCase --
2080  *      Change the string to all uppercase or all lowercase
2081  *
2082  * Input:
2083  *	str		String to modify
2084  *	upper		TRUE -> uppercase, else lowercase
2085  *
2086  * Results:
2087  *      The string with case changed
2088  *
2089  * Side Effects:
2090  *      None.
2091  *
2092  *-----------------------------------------------------------------------
2093  */
2094 static char *
2095 VarChangeCase(char *str, int upper)
2096 {
2097    Buffer         buf;
2098    int            (*modProc)(int);
2099 
2100    modProc = (upper ? toupper : tolower);
2101    buf = Buf_Init(0);
2102    for (; *str ; str++) {
2103        Buf_AddByte(buf, (Byte)modProc(*str));
2104    }
2105    Buf_AddByte(buf, (Byte)'\0');
2106    str = (char *)Buf_GetAll(buf, NULL);
2107    Buf_Destroy(buf, FALSE);
2108    return str;
2109 }
2110 
2111 /*
2112  * Now we need to apply any modifiers the user wants applied.
2113  * These are:
2114  *  	  :M<pattern>	words which match the given <pattern>.
2115  *  	  	    	<pattern> is of the standard file
2116  *  	  	    	wildcarding form.
2117  *  	  :N<pattern>	words which do not match the given <pattern>.
2118  *  	  :S<d><pat1><d><pat2><d>[1gW]
2119  *  	  	    	Substitute <pat2> for <pat1> in the value
2120  *  	  :C<d><pat1><d><pat2><d>[1gW]
2121  *  	  	    	Substitute <pat2> for regex <pat1> in the value
2122  *  	  :H	    	Substitute the head of each word
2123  *  	  :T	    	Substitute the tail of each word
2124  *  	  :E	    	Substitute the extension (minus '.') of
2125  *  	  	    	each word
2126  *  	  :R	    	Substitute the root of each word
2127  *  	  	    	(pathname minus the suffix).
2128  *		  :O		("Order") Alphabeticaly sort words in variable.
2129  *		  :Ox		("intermiX") Randomize words in variable.
2130  *		  :u		("uniq") Remove adjacent duplicate words.
2131  *		  :tu		Converts the variable contents to uppercase.
2132  *		  :tl		Converts the variable contents to lowercase.
2133  *		  :ts[c]	Sets varSpace - the char used to
2134  *				separate words to 'c'. If 'c' is
2135  *				omitted then no separation is used.
2136  *		  :tW		Treat the variable contents as a single
2137  *				word, even if it contains spaces.
2138  *				(Mnemonic: one big 'W'ord.)
2139  *		  :tw		Treat the variable contents as multiple
2140  *				space-separated words.
2141  *				(Mnemonic: many small 'w'ords.)
2142  *		  :[index]	Select a single word from the value.
2143  *		  :[start..end]	Select multiple words from the value.
2144  *		  :[*] or :[0]	Select the entire value, as a single
2145  *				word.  Equivalent to :tW.
2146  *		  :[@]		Select the entire value, as multiple
2147  *				words.	Undoes the effect of :[*].
2148  *				Equivalent to :tw.
2149  *		  :[#]		Returns the number of words in the value.
2150  *
2151  *		  :?<true-value>:<false-value>
2152  *				If the variable evaluates to true, return
2153  *				true value, else return the second value.
2154  *	    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
2155  *	    	    	    	the invocation.
2156  *		  :sh		Treat the current value as a command
2157  *				to be run, new value is its output.
2158  * The following added so we can handle ODE makefiles.
2159  *		  :@<tmpvar>@<newval>@
2160  *				Assign a temporary local variable <tmpvar>
2161  *				to the current value of each word in turn
2162  *				and replace each word with the result of
2163  *				evaluating <newval>
2164  *		  :D<newval>	Use <newval> as value if variable defined
2165  *		  :U<newval>	Use <newval> as value if variable undefined
2166  *		  :L		Use the name of the variable as the value.
2167  *		  :P		Use the path of the node that has the same
2168  *				name as the variable as the value.  This
2169  *				basically includes an implied :L so that
2170  *				the common method of refering to the path
2171  *				of your dependent 'x' in a rule is to use
2172  *				the form '${x:P}'.
2173  *		  :!<cmd>!	Run cmd much the same as :sh run's the
2174  *				current value of the variable.
2175  * The ::= modifiers, actually assign a value to the variable.
2176  * Their main purpose is in supporting modifiers of .for loop
2177  * iterators and other obscure uses.  They always expand to
2178  * nothing.  In a target rule that would otherwise expand to an
2179  * empty line they can be preceded with @: to keep make happy.
2180  * Eg.
2181  *
2182  * foo:	.USE
2183  * .for i in ${.TARGET} ${.TARGET:R}.gz
2184  * 		@: ${t::=$i}
2185  *		@echo blah ${t:T}
2186  * .endfor
2187  *
2188  *		  ::=<str>	Assigns <str> as the new value of variable.
2189  *		  ::?=<str>	Assigns <str> as value of variable if
2190  *				it was not already set.
2191  *		  ::+=<str>	Appends <str> to variable.
2192  *		  ::!=<cmd>	Assigns output of <cmd> as the new value of
2193  *				variable.
2194  */
2195 
2196 static char *
2197 ApplyModifiers(char *nstr, const char *tstr,
2198 	       int startc, int endc,
2199 	       Var *v, GNode *ctxt, Boolean errnum,
2200 	       int *lengthPtr, void **freePtr)
2201 {
2202     const char 	   *start;
2203     const char     *cp;    	/* Secondary pointer into str (place marker
2204 				 * for tstr) */
2205     char	   *newStr;	/* New value to return */
2206     char	    termc;	/* Character which terminated scan */
2207     int             cnt;	/* Used to count brace pairs when variable in
2208 				 * in parens or braces */
2209     char	delim;
2210     int		modifier;	/* that we are processing */
2211     Var_Parse_State parsestate; /* Flags passed to helper functions */
2212 
2213     delim = '\0';
2214     parsestate.oneBigWord = FALSE;
2215     parsestate.varSpace = ' ';	/* word separator */
2216 
2217     start = cp = tstr;
2218 
2219     while (*tstr && *tstr != endc) {
2220 
2221 	if (*tstr == '$') {
2222 	    /*
2223 	     * We have some complex modifiers in a variable.
2224 	     */
2225 	    void *freeIt;
2226 	    char *rval;
2227 	    int rlen;
2228 
2229 	    rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
2230 
2231 	    if (DEBUG(VAR)) {
2232 		fprintf(debug_file, "Got '%s' from '%.*s'%.*s\n",
2233 		       rval, rlen, tstr, rlen, tstr + rlen);
2234 	    }
2235 
2236 	    tstr += rlen;
2237 
2238 	    if (rval != NULL && *rval) {
2239 		int used;
2240 
2241 		nstr = ApplyModifiers(nstr, rval,
2242 				      0, 0,
2243 				      v, ctxt, errnum, &used, freePtr);
2244 		if (nstr == var_Error
2245 		    || (nstr == varNoError && errnum == 0)
2246 		    || strlen(rval) != (size_t) used) {
2247 		    if (freeIt)
2248 			free(freeIt);
2249 		    goto out;		/* error already reported */
2250 		}
2251 	    }
2252 	    if (freeIt)
2253 		free(freeIt);
2254 	    if (*tstr == ':')
2255 		tstr++;
2256 	    else if (!*tstr && endc) {
2257 		Error("Unclosed variable specification for %s", v->name);
2258 		goto out;
2259 	    }
2260 	    continue;
2261 	}
2262 	if (DEBUG(VAR)) {
2263 	    fprintf(debug_file, "Applying :%c to \"%s\"\n", *tstr, nstr);
2264 	}
2265 	newStr = var_Error;
2266 	switch ((modifier = *tstr)) {
2267 	case ':':
2268 	    {
2269 		if (tstr[1] == '=' ||
2270 		    (tstr[2] == '=' &&
2271 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
2272 		    /*
2273 		     * "::=", "::!=", "::+=", or "::?="
2274 		     */
2275 		    GNode *v_ctxt;		/* context where v belongs */
2276 		    const char *emsg;
2277 		    char *sv_name;
2278 		    VarPattern	pattern;
2279 		    int	how;
2280 
2281 		    v_ctxt = ctxt;
2282 		    sv_name = NULL;
2283 		    ++tstr;
2284 		    if (v->flags & VAR_JUNK) {
2285 			/*
2286 			 * We need to estrdup() it incase
2287 			 * VarGetPattern() recurses.
2288 			 */
2289 			sv_name = v->name;
2290 			v->name = estrdup(v->name);
2291 		    } else if (ctxt != VAR_GLOBAL) {
2292 			Var *gv = VarFind(v->name, ctxt, 0);
2293 			if (gv == (Var *)NIL)
2294 			    v_ctxt = VAR_GLOBAL;
2295 			else
2296 			    VarFreeEnv(gv, TRUE);
2297 		    }
2298 
2299 		    switch ((how = *tstr)) {
2300 		    case '+':
2301 		    case '?':
2302 		    case '!':
2303 			cp = &tstr[2];
2304 			break;
2305 		    default:
2306 			cp = ++tstr;
2307 			break;
2308 		    }
2309 		    delim = BRCLOSE;
2310 		    pattern.flags = 0;
2311 
2312 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2313 						&cp, delim, NULL,
2314 						&pattern.rightLen,
2315 						NULL);
2316 		    if (v->flags & VAR_JUNK) {
2317 			/* restore original name */
2318 			free(v->name);
2319 			v->name = sv_name;
2320 		    }
2321 		    if (pattern.rhs == NULL)
2322 			goto cleanup;
2323 
2324 		    termc = *--cp;
2325 		    delim = '\0';
2326 
2327 		    switch (how) {
2328 		    case '+':
2329 			Var_Append(v->name, pattern.rhs, v_ctxt);
2330 			break;
2331 		    case '!':
2332 			newStr = Cmd_Exec(pattern.rhs, &emsg);
2333 			if (emsg)
2334 			    Error(emsg, nstr);
2335 			else
2336 			    Var_Set(v->name, newStr,  v_ctxt, 0);
2337 			if (newStr)
2338 			    free(newStr);
2339 			break;
2340 		    case '?':
2341 			if ((v->flags & VAR_JUNK) == 0)
2342 			    break;
2343 			/* FALLTHROUGH */
2344 		    default:
2345 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
2346 			break;
2347 		    }
2348 		    free(UNCONST(pattern.rhs));
2349 		    newStr = var_Error;
2350 		    break;
2351 		}
2352 		goto default_case; /* "::<unrecognised>" */
2353 	    }
2354 	case '@':
2355 	    {
2356 		VarLoop_t	loop;
2357 		int flags = VAR_NOSUBST;
2358 
2359 		cp = ++tstr;
2360 		delim = '@';
2361 		if ((loop.tvar = VarGetPattern(ctxt, &parsestate, errnum,
2362 					       &cp, delim,
2363 					       &flags, &loop.tvarLen,
2364 					       NULL)) == NULL)
2365 		    goto cleanup;
2366 
2367 		if ((loop.str = VarGetPattern(ctxt, &parsestate, errnum,
2368 					      &cp, delim,
2369 					      &flags, &loop.strLen,
2370 					      NULL)) == NULL)
2371 		    goto cleanup;
2372 
2373 		termc = *cp;
2374 		delim = '\0';
2375 
2376 		loop.errnum = errnum;
2377 		loop.ctxt = ctxt;
2378 		newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
2379 				   &loop);
2380 		free(loop.tvar);
2381 		free(loop.str);
2382 		break;
2383 	    }
2384 	case 'D':
2385 	case 'U':
2386 	    {
2387 		Buffer  buf;    	/* Buffer for patterns */
2388 		int	    wantit;	/* want data in buffer */
2389 
2390 		/*
2391 		 * Pass through tstr looking for 1) escaped delimiters,
2392 		 * '$'s and backslashes (place the escaped character in
2393 		 * uninterpreted) and 2) unescaped $'s that aren't before
2394 		 * the delimiter (expand the variable substitution).
2395 		 * The result is left in the Buffer buf.
2396 		 */
2397 		buf = Buf_Init(0);
2398 		for (cp = tstr + 1;
2399 		     *cp != endc && *cp != ':' && *cp != '\0';
2400 		     cp++) {
2401 		    if ((*cp == '\\') &&
2402 			((cp[1] == ':') ||
2403 			 (cp[1] == '$') ||
2404 			 (cp[1] == endc) ||
2405 			 (cp[1] == '\\')))
2406 			{
2407 			    Buf_AddByte(buf, (Byte)cp[1]);
2408 			    cp++;
2409 			} else if (*cp == '$') {
2410 			    /*
2411 			     * If unescaped dollar sign, assume it's a
2412 			     * variable substitution and recurse.
2413 			     */
2414 			    char    *cp2;
2415 			    int	    len;
2416 			    void    *freeIt;
2417 
2418 			    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
2419 			    Buf_AddBytes(buf, strlen(cp2), (Byte *)cp2);
2420 			    if (freeIt)
2421 				free(freeIt);
2422 			    cp += len - 1;
2423 			} else {
2424 			    Buf_AddByte(buf, (Byte)*cp);
2425 			}
2426 		}
2427 		Buf_AddByte(buf, (Byte)'\0');
2428 
2429 		termc = *cp;
2430 
2431 		if (*tstr == 'U')
2432 		    wantit = ((v->flags & VAR_JUNK) != 0);
2433 		else
2434 		    wantit = ((v->flags & VAR_JUNK) == 0);
2435 		if ((v->flags & VAR_JUNK) != 0)
2436 		    v->flags |= VAR_KEEP;
2437 		if (wantit) {
2438 		    newStr = (char *)Buf_GetAll(buf, NULL);
2439 		    Buf_Destroy(buf, FALSE);
2440 		} else {
2441 		    newStr = nstr;
2442 		    Buf_Destroy(buf, TRUE);
2443 		}
2444 		break;
2445 	    }
2446 	case 'L':
2447 	    {
2448 		if ((v->flags & VAR_JUNK) != 0)
2449 		    v->flags |= VAR_KEEP;
2450 		newStr = estrdup(v->name);
2451 		cp = ++tstr;
2452 		termc = *tstr;
2453 		break;
2454 	    }
2455 	case 'P':
2456 	    {
2457 		GNode *gn;
2458 
2459 		if ((v->flags & VAR_JUNK) != 0)
2460 		    v->flags |= VAR_KEEP;
2461 		gn = Targ_FindNode(v->name, TARG_NOCREATE);
2462 		if (gn == NILGNODE || gn->type & OP_NOPATH) {
2463 		    newStr = NULL;
2464 		} else if (gn->path) {
2465 		    newStr = estrdup(gn->path);
2466 		} else {
2467 		    newStr = Dir_FindFile(v->name, Suff_FindPath(gn));
2468 		}
2469 		if (!newStr) {
2470 		    newStr = estrdup(v->name);
2471 		}
2472 		cp = ++tstr;
2473 		termc = *tstr;
2474 		break;
2475 	    }
2476 	case '!':
2477 	    {
2478 		const char *emsg;
2479 		VarPattern 	    pattern;
2480 		pattern.flags = 0;
2481 
2482 		delim = '!';
2483 
2484 		cp = ++tstr;
2485 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2486 						 &cp, delim,
2487 						 NULL, &pattern.rightLen,
2488 						 NULL)) == NULL)
2489 		    goto cleanup;
2490 		newStr = Cmd_Exec(pattern.rhs, &emsg);
2491 		free(UNCONST(pattern.rhs));
2492 		if (emsg)
2493 		    Error(emsg, nstr);
2494 		termc = *cp;
2495 		delim = '\0';
2496 		if (v->flags & VAR_JUNK) {
2497 		    v->flags |= VAR_KEEP;
2498 		}
2499 		break;
2500 	    }
2501 	case '[':
2502 	    {
2503 		/*
2504 		 * Look for the closing ']', recursively
2505 		 * expanding any embedded variables.
2506 		 *
2507 		 * estr is a pointer to the expanded result,
2508 		 * which we must free().
2509 		 */
2510 		char *estr;
2511 
2512 		cp = tstr+1; /* point to char after '[' */
2513 		delim = ']'; /* look for closing ']' */
2514 		estr = VarGetPattern(ctxt, &parsestate,
2515 				     errnum, &cp, delim,
2516 				     NULL, NULL, NULL);
2517 		if (estr == NULL)
2518 		    goto cleanup; /* report missing ']' */
2519 		/* now cp points just after the closing ']' */
2520 		delim = '\0';
2521 		if (cp[0] != ':' && cp[0] != endc) {
2522 		    /* Found junk after ']' */
2523 		    free(estr);
2524 		    goto bad_modifier;
2525 		}
2526 		if (estr[0] == '\0') {
2527 		    /* Found empty square brackets in ":[]". */
2528 		    free(estr);
2529 		    goto bad_modifier;
2530 		} else if (estr[0] == '#' && estr[1] == '\0') {
2531 		    /* Found ":[#]" */
2532 
2533 		    /*
2534 		     * We will need enough space for the decimal
2535 		     * representation of an int.  We calculate the
2536 		     * space needed for the octal representation,
2537 		     * and add enough slop to cope with a '-' sign
2538 		     * (which should never be needed) and a '\0'
2539 		     * string terminator.
2540 		     */
2541 		    int newStrSize =
2542 			(sizeof(int) * CHAR_BIT + 2) / 3 + 2;
2543 
2544 		    newStr = emalloc(newStrSize);
2545 		    if (parsestate.oneBigWord) {
2546 			strncpy(newStr, "1", newStrSize);
2547 		    } else {
2548 			/* XXX: brk_string() is a rather expensive
2549 			 * way of counting words. */
2550 			char **av;
2551 			char *as;
2552 			int ac;
2553 
2554 			av = brk_string(nstr, &ac, FALSE, &as);
2555 			snprintf(newStr, newStrSize,  "%d", ac);
2556 			free(as);
2557 			free(av);
2558 		    }
2559 		    termc = *cp;
2560 		    free(estr);
2561 		    break;
2562 		} else if (estr[0] == '*' && estr[1] == '\0') {
2563 		    /* Found ":[*]" */
2564 		    parsestate.oneBigWord = TRUE;
2565 		    newStr = nstr;
2566 		    termc = *cp;
2567 		    free(estr);
2568 		    break;
2569 		} else if (estr[0] == '@' && estr[1] == '\0') {
2570 		    /* Found ":[@]" */
2571 		    parsestate.oneBigWord = FALSE;
2572 		    newStr = nstr;
2573 		    termc = *cp;
2574 		    free(estr);
2575 		    break;
2576 		} else {
2577 		    /*
2578 		     * We expect estr to contain a single
2579 		     * integer for :[N], or two integers
2580 		     * separated by ".." for :[start..end].
2581 		     */
2582 		    char *ep;
2583 
2584 		    VarSelectWords_t seldata = { 0, 0 };
2585 
2586 		    seldata.start = strtol(estr, &ep, 0);
2587 		    if (ep == estr) {
2588 			/* Found junk instead of a number */
2589 			free(estr);
2590 			goto bad_modifier;
2591 		    } else if (ep[0] == '\0') {
2592 			/* Found only one integer in :[N] */
2593 			seldata.end = seldata.start;
2594 		    } else if (ep[0] == '.' && ep[1] == '.' &&
2595 			       ep[2] != '\0') {
2596 			/* Expecting another integer after ".." */
2597 			ep += 2;
2598 			seldata.end = strtol(ep, &ep, 0);
2599 			if (ep[0] != '\0') {
2600 			    /* Found junk after ".." */
2601 			    free(estr);
2602 			    goto bad_modifier;
2603 			}
2604 		    } else {
2605 			/* Found junk instead of ".." */
2606 			free(estr);
2607 			goto bad_modifier;
2608 		    }
2609 		    /*
2610 		     * Now seldata is properly filled in,
2611 		     * but we still have to check for 0 as
2612 		     * a special case.
2613 		     */
2614 		    if (seldata.start == 0 && seldata.end == 0) {
2615 			/* ":[0]" or perhaps ":[0..0]" */
2616 			parsestate.oneBigWord = TRUE;
2617 			newStr = nstr;
2618 			termc = *cp;
2619 			free(estr);
2620 			break;
2621 		    } else if (seldata.start == 0 ||
2622 			       seldata.end == 0) {
2623 			/* ":[0..N]" or ":[N..0]" */
2624 			free(estr);
2625 			goto bad_modifier;
2626 		    }
2627 		    /*
2628 		     * Normal case: select the words
2629 		     * described by seldata.
2630 		     */
2631 		    newStr = VarSelectWords(ctxt, &parsestate,
2632 					    nstr, &seldata);
2633 
2634 		    termc = *cp;
2635 		    free(estr);
2636 		    break;
2637 		}
2638 
2639 	    }
2640 	case 't':
2641 	    {
2642 		cp = tstr + 1;	/* make sure it is set */
2643 		if (tstr[1] != endc && tstr[1] != ':') {
2644 		    if (tstr[1] == 's') {
2645 			/*
2646 			 * Use the char (if any) at tstr[2]
2647 			 * as the word separator.
2648 			 */
2649 			VarPattern pattern;
2650 
2651 			if (tstr[2] != endc &&
2652 			    (tstr[3] == endc || tstr[3] == ':')) {
2653 			    /* ":ts<unrecognised><endc>" or
2654 			     * ":ts<unrecognised>:" */
2655 			    parsestate.varSpace = tstr[2];
2656 			    cp = tstr + 3;
2657 			} else if (tstr[2] == endc || tstr[2] == ':') {
2658 			    /* ":ts<endc>" or ":ts:" */
2659 			    parsestate.varSpace = 0; /* no separator */
2660 			    cp = tstr + 2;
2661 			} else if (tstr[2] == '\\') {
2662 			    switch (tstr[3]) {
2663 			    case 'n':
2664 				parsestate.varSpace = '\n';
2665 				cp = tstr + 4;
2666 				break;
2667 			    case 't':
2668 				parsestate.varSpace = '\t';
2669 				cp = tstr + 4;
2670 				break;
2671 			    default:
2672 				if (isdigit((unsigned char)tstr[3])) {
2673 				    char *ep;
2674 
2675 				    parsestate.varSpace =
2676 					strtoul(&tstr[3], &ep, 0);
2677 				    if (*ep != ':' && *ep != endc)
2678 					goto bad_modifier;
2679 				    cp = ep;
2680 				} else {
2681 				    /*
2682 				     * ":ts<backslash><unrecognised>".
2683 				     */
2684 				    goto bad_modifier;
2685 				}
2686 				break;
2687 			    }
2688 			} else {
2689 			    /*
2690 			     * Found ":ts<unrecognised><unrecognised>".
2691 			     */
2692 			    goto bad_modifier;
2693 			}
2694 
2695 			termc = *cp;
2696 
2697 			/*
2698 			 * We cannot be certain that VarModify
2699 			 * will be used - even if there is a
2700 			 * subsequent modifier, so do a no-op
2701 			 * VarSubstitute now to for str to be
2702 			 * re-expanded without the spaces.
2703 			 */
2704 			pattern.flags = VAR_SUB_ONE;
2705 			pattern.lhs = pattern.rhs = "\032";
2706 			pattern.leftLen = pattern.rightLen = 1;
2707 
2708 			newStr = VarModify(ctxt, &parsestate, nstr,
2709 					   VarSubstitute,
2710 					   &pattern);
2711 		    } else if (tstr[2] == endc || tstr[2] == ':') {
2712 			/*
2713 			 * Check for two-character options:
2714 			 * ":tu", ":tl"
2715 			 */
2716 			if (tstr[1] == 'u' || tstr[1] == 'l') {
2717 			    newStr = VarChangeCase(nstr, (tstr[1] == 'u'));
2718 			    cp = tstr + 2;
2719 			    termc = *cp;
2720 			} else if (tstr[1] == 'W' || tstr[1] == 'w') {
2721 			    parsestate.oneBigWord = (tstr[1] == 'W');
2722 			    newStr = nstr;
2723 			    cp = tstr + 2;
2724 			    termc = *cp;
2725 			} else {
2726 			    /* Found ":t<unrecognised>:" or
2727 			     * ":t<unrecognised><endc>". */
2728 			    goto bad_modifier;
2729 			}
2730 		    } else {
2731 			/*
2732 			 * Found ":t<unrecognised><unrecognised>".
2733 			 */
2734 			goto bad_modifier;
2735 		    }
2736 		} else {
2737 		    /*
2738 		     * Found ":t<endc>" or ":t:".
2739 		     */
2740 		    goto bad_modifier;
2741 		}
2742 		break;
2743 	    }
2744 	case 'N':
2745 	case 'M':
2746 	    {
2747 		char    *pattern;
2748 		const char *endpat; /* points just after end of pattern */
2749 		char    *cp2;
2750 		Boolean copy;	/* pattern should be, or has been, copied */
2751 		int nest;
2752 
2753 		copy = FALSE;
2754 		nest = 1;
2755 		/*
2756 		 * In the loop below, ignore ':' unless we are at
2757 		 * (or back to) the original brace level.
2758 		 * XXX This will likely not work right if $() and ${}
2759 		 * are intermixed.
2760 		 */
2761 		for (cp = tstr + 1;
2762 		     *cp != '\0' && !(*cp == ':' && nest == 1);
2763 		     cp++)
2764 		    {
2765 			if (*cp == '\\' &&
2766 			    (cp[1] == ':' ||
2767 			     cp[1] == endc || cp[1] == startc)) {
2768 			    copy = TRUE;
2769 			    cp++;
2770 			    continue;
2771 			}
2772 			if (*cp == startc)
2773 			    ++nest;
2774 			if (*cp == endc) {
2775 			    --nest;
2776 			    if (nest == 0)
2777 				break;
2778 			}
2779 		    }
2780 		termc = *cp;
2781 		endpat = cp;
2782 		if (copy) {
2783 		    /*
2784 		     * Need to compress the \:'s out of the pattern, so
2785 		     * allocate enough room to hold the uncompressed
2786 		     * pattern (note that cp started at tstr+1, so
2787 		     * cp - tstr takes the null byte into account) and
2788 		     * compress the pattern into the space.
2789 		     */
2790 		    pattern = emalloc(cp - tstr);
2791 		    for (cp2 = pattern, cp = tstr + 1;
2792 			 cp < endpat;
2793 			 cp++, cp2++)
2794 			{
2795 			    if ((*cp == '\\') && (cp+1 < endpat) &&
2796 				(cp[1] == ':' || cp[1] == endc)) {
2797 				cp++;
2798 			    }
2799 			    *cp2 = *cp;
2800 			}
2801 		    *cp2 = '\0';
2802 		    endpat = cp2;
2803 		} else {
2804 		    /*
2805 		     * Either Var_Subst or VarModify will need a
2806 		     * nul-terminated string soon, so construct one now.
2807 		     */
2808 		    pattern = estrndup(tstr+1, endpat - (tstr + 1));
2809 		    copy = TRUE;
2810 		}
2811 		if (strchr(pattern, '$') != NULL) {
2812 		    /*
2813 		     * pattern contains embedded '$', so use Var_Subst to
2814 		     * expand it.
2815 		     */
2816 		    cp2 = pattern;
2817 		    pattern = Var_Subst(NULL, cp2, ctxt, errnum);
2818 		    if (copy)
2819 			free(cp2);
2820 		    copy = TRUE;
2821 		}
2822 		if (*tstr == 'M' || *tstr == 'm') {
2823 		    newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
2824 				       pattern);
2825 		} else {
2826 		    newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
2827 				       pattern);
2828 		}
2829 		if (copy) {
2830 		    free(pattern);
2831 		}
2832 		break;
2833 	    }
2834 	case 'S':
2835 	    {
2836 		VarPattern 	    pattern;
2837 		Var_Parse_State tmpparsestate;
2838 
2839 		pattern.flags = 0;
2840 		tmpparsestate = parsestate;
2841 		delim = tstr[1];
2842 		tstr += 2;
2843 
2844 		/*
2845 		 * If pattern begins with '^', it is anchored to the
2846 		 * start of the word -- skip over it and flag pattern.
2847 		 */
2848 		if (*tstr == '^') {
2849 		    pattern.flags |= VAR_MATCH_START;
2850 		    tstr += 1;
2851 		}
2852 
2853 		cp = tstr;
2854 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
2855 						 &cp, delim,
2856 						 &pattern.flags,
2857 						 &pattern.leftLen,
2858 						 NULL)) == NULL)
2859 		    goto cleanup;
2860 
2861 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2862 						 &cp, delim, NULL,
2863 						 &pattern.rightLen,
2864 						 &pattern)) == NULL)
2865 		    goto cleanup;
2866 
2867 		/*
2868 		 * Check for global substitution. If 'g' after the final
2869 		 * delimiter, substitution is global and is marked that
2870 		 * way.
2871 		 */
2872 		for (;; cp++) {
2873 		    switch (*cp) {
2874 		    case 'g':
2875 			pattern.flags |= VAR_SUB_GLOBAL;
2876 			continue;
2877 		    case '1':
2878 			pattern.flags |= VAR_SUB_ONE;
2879 			continue;
2880 		    case 'W':
2881 			tmpparsestate.oneBigWord = TRUE;
2882 			continue;
2883 		    }
2884 		    break;
2885 		}
2886 
2887 		termc = *cp;
2888 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
2889 				   VarSubstitute,
2890 				   &pattern);
2891 
2892 		/*
2893 		 * Free the two strings.
2894 		 */
2895 		free(UNCONST(pattern.lhs));
2896 		free(UNCONST(pattern.rhs));
2897 		delim = '\0';
2898 		break;
2899 	    }
2900 	case '?':
2901 	    {
2902 		VarPattern 	pattern;
2903 		Boolean	value;
2904 
2905 		/* find ':', and then substitute accordingly */
2906 
2907 		pattern.flags = 0;
2908 
2909 		cp = ++tstr;
2910 		delim = ':';
2911 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
2912 						 &cp, delim, NULL,
2913 						 &pattern.leftLen,
2914 						 NULL)) == NULL)
2915 		    goto cleanup;
2916 
2917 		/* BROPEN or PROPEN */
2918 		delim = endc;
2919 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
2920 						 &cp, delim, NULL,
2921 						 &pattern.rightLen,
2922 						 NULL)) == NULL)
2923 		    goto cleanup;
2924 
2925 		termc = *--cp;
2926 		delim = '\0';
2927 		if (Cond_EvalExpression(1, v->name, &value, 0)
2928 		    == COND_INVALID) {
2929 		    Error("Bad conditional expression `%s' in %s?%s:%s",
2930 			  v->name, v->name, pattern.lhs, pattern.rhs);
2931 		    goto cleanup;
2932 		}
2933 
2934 		if (value) {
2935 		    newStr = UNCONST(pattern.lhs);
2936 		    free(UNCONST(pattern.rhs));
2937 		} else {
2938 		    newStr = UNCONST(pattern.rhs);
2939 		    free(UNCONST(pattern.lhs));
2940 		}
2941 		if (v->flags & VAR_JUNK) {
2942 		    v->flags |= VAR_KEEP;
2943 		}
2944 		break;
2945 	    }
2946 #ifndef NO_REGEX
2947 	case 'C':
2948 	    {
2949 		VarREPattern    pattern;
2950 		char           *re;
2951 		int             error;
2952 		Var_Parse_State tmpparsestate;
2953 
2954 		pattern.flags = 0;
2955 		tmpparsestate = parsestate;
2956 		delim = tstr[1];
2957 		tstr += 2;
2958 
2959 		cp = tstr;
2960 
2961 		if ((re = VarGetPattern(ctxt, &parsestate, errnum, &cp, delim,
2962 					NULL, NULL, NULL)) == NULL)
2963 		    goto cleanup;
2964 
2965 		if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
2966 						     errnum, &cp, delim, NULL,
2967 						     NULL, NULL)) == NULL){
2968 		    free(re);
2969 		    goto cleanup;
2970 		}
2971 
2972 		for (;; cp++) {
2973 		    switch (*cp) {
2974 		    case 'g':
2975 			pattern.flags |= VAR_SUB_GLOBAL;
2976 			continue;
2977 		    case '1':
2978 			pattern.flags |= VAR_SUB_ONE;
2979 			continue;
2980 		    case 'W':
2981 			tmpparsestate.oneBigWord = TRUE;
2982 			continue;
2983 		    }
2984 		    break;
2985 		}
2986 
2987 		termc = *cp;
2988 
2989 		error = regcomp(&pattern.re, re, REG_EXTENDED);
2990 		free(re);
2991 		if (error)  {
2992 		    *lengthPtr = cp - start + 1;
2993 		    VarREError(error, &pattern.re, "RE substitution error");
2994 		    free(pattern.replace);
2995 		    goto cleanup;
2996 		}
2997 
2998 		pattern.nsub = pattern.re.re_nsub + 1;
2999 		if (pattern.nsub < 1)
3000 		    pattern.nsub = 1;
3001 		if (pattern.nsub > 10)
3002 		    pattern.nsub = 10;
3003 		pattern.matches = emalloc(pattern.nsub *
3004 					  sizeof(regmatch_t));
3005 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
3006 				   VarRESubstitute,
3007 				   &pattern);
3008 		regfree(&pattern.re);
3009 		free(pattern.replace);
3010 		free(pattern.matches);
3011 		delim = '\0';
3012 		break;
3013 	    }
3014 #endif
3015 	case 'Q':
3016 	    if (tstr[1] == endc || tstr[1] == ':') {
3017 		newStr = VarQuote(nstr);
3018 		cp = tstr + 1;
3019 		termc = *cp;
3020 		break;
3021 	    }
3022 	    goto default_case;
3023 	case 'T':
3024 	    if (tstr[1] == endc || tstr[1] == ':') {
3025 		newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
3026 				   NULL);
3027 		cp = tstr + 1;
3028 		termc = *cp;
3029 		break;
3030 	    }
3031 	    goto default_case;
3032 	case 'H':
3033 	    if (tstr[1] == endc || tstr[1] == ':') {
3034 		newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
3035 				   NULL);
3036 		cp = tstr + 1;
3037 		termc = *cp;
3038 		break;
3039 	    }
3040 	    goto default_case;
3041 	case 'E':
3042 	    if (tstr[1] == endc || tstr[1] == ':') {
3043 		newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
3044 				   NULL);
3045 		cp = tstr + 1;
3046 		termc = *cp;
3047 		break;
3048 	    }
3049 	    goto default_case;
3050 	case 'R':
3051 	    if (tstr[1] == endc || tstr[1] == ':') {
3052 		newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
3053 				   NULL);
3054 		cp = tstr + 1;
3055 		termc = *cp;
3056 		break;
3057 	    }
3058 	    goto default_case;
3059 	case 'O':
3060 	    {
3061 		char otype;
3062 
3063 		cp = tstr + 1;	/* skip to the rest in any case */
3064 		if (tstr[1] == endc || tstr[1] == ':') {
3065 		    otype = 's';
3066 		    termc = *cp;
3067 		} else if ( (tstr[1] == 'x') &&
3068 			    (tstr[2] == endc || tstr[2] == ':') ) {
3069 		    otype = tstr[1];
3070 		    cp = tstr + 2;
3071 		    termc = *cp;
3072 		} else {
3073 		    goto bad_modifier;
3074 		}
3075 		newStr = VarOrder(nstr, otype);
3076 		break;
3077 	    }
3078 	case 'u':
3079 	    if (tstr[1] == endc || tstr[1] == ':') {
3080 		newStr = VarUniq(nstr);
3081 		cp = tstr + 1;
3082 		termc = *cp;
3083 		break;
3084 	    }
3085 	    goto default_case;
3086 #ifdef SUNSHCMD
3087 	case 's':
3088 	    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
3089 		const char *emsg;
3090 		newStr = Cmd_Exec(nstr, &emsg);
3091 		if (emsg)
3092 		    Error(emsg, nstr);
3093 		cp = tstr + 2;
3094 		termc = *cp;
3095 		break;
3096 	    }
3097 	    goto default_case;
3098 #endif
3099 	default:
3100 	default_case:
3101 	{
3102 #ifdef SYSVVARSUB
3103 	    /*
3104 	     * This can either be a bogus modifier or a System-V
3105 	     * substitution command.
3106 	     */
3107 	    VarPattern      pattern;
3108 	    Boolean         eqFound;
3109 
3110 	    pattern.flags = 0;
3111 	    eqFound = FALSE;
3112 	    /*
3113 	     * First we make a pass through the string trying
3114 	     * to verify it is a SYSV-make-style translation:
3115 	     * it must be: <string1>=<string2>)
3116 	     */
3117 	    cp = tstr;
3118 	    cnt = 1;
3119 	    while (*cp != '\0' && cnt) {
3120 		if (*cp == '=') {
3121 		    eqFound = TRUE;
3122 		    /* continue looking for endc */
3123 		}
3124 		else if (*cp == endc)
3125 		    cnt--;
3126 		else if (*cp == startc)
3127 		    cnt++;
3128 		if (cnt)
3129 		    cp++;
3130 	    }
3131 	    if (*cp == endc && eqFound) {
3132 
3133 		/*
3134 		 * Now we break this sucker into the lhs and
3135 		 * rhs. We must null terminate them of course.
3136 		 */
3137 		delim='=';
3138 		cp = tstr;
3139 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
3140 						 errnum, &cp, delim, &pattern.flags,
3141 						 &pattern.leftLen, NULL)) == NULL)
3142 		    goto cleanup;
3143 		delim = endc;
3144 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
3145 						 errnum, &cp, delim, NULL, &pattern.rightLen,
3146 						 &pattern)) == NULL)
3147 		    goto cleanup;
3148 
3149 		/*
3150 		 * SYSV modifications happen through the whole
3151 		 * string. Note the pattern is anchored at the end.
3152 		 */
3153 		termc = *--cp;
3154 		delim = '\0';
3155 		newStr = VarModify(ctxt, &parsestate, nstr,
3156 				   VarSYSVMatch,
3157 				   &pattern);
3158 		free(UNCONST(pattern.lhs));
3159 		free(UNCONST(pattern.rhs));
3160 	    } else
3161 #endif
3162 		{
3163 		    Error("Unknown modifier '%c'", *tstr);
3164 		    for (cp = tstr+1;
3165 			 *cp != ':' && *cp != endc && *cp != '\0';
3166 			 cp++)
3167 			continue;
3168 		    termc = *cp;
3169 		    newStr = var_Error;
3170 		}
3171 	    }
3172 	}
3173 	if (DEBUG(VAR)) {
3174 	    fprintf(debug_file, "Result of :%c is \"%s\"\n", modifier, newStr);
3175 	}
3176 
3177 	if (newStr != nstr) {
3178 	    if (*freePtr) {
3179 		free(nstr);
3180 		*freePtr = NULL;
3181 	    }
3182 	    nstr = newStr;
3183 	    if (nstr != var_Error && nstr != varNoError) {
3184 		*freePtr = nstr;
3185 	    }
3186 	}
3187 	if (termc == '\0' && endc != '\0') {
3188 	    Error("Unclosed variable specification for %s", v->name);
3189 	} else if (termc == ':') {
3190 	    cp++;
3191 	}
3192 	tstr = cp;
3193     }
3194  out:
3195     *lengthPtr = tstr - start;
3196     return (nstr);
3197 
3198  bad_modifier:
3199     /* "{(" */
3200     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
3201 	  v->name);
3202 
3203  cleanup:
3204     *lengthPtr = cp - start;
3205     if (delim != '\0')
3206 	Error("Unclosed substitution for %s (%c missing)",
3207 	      v->name, delim);
3208     if (*freePtr) {
3209 	free(*freePtr);
3210 	*freePtr = NULL;
3211     }
3212     return (var_Error);
3213 }
3214 
3215 /*-
3216  *-----------------------------------------------------------------------
3217  * Var_Parse --
3218  *	Given the start of a variable invocation, extract the variable
3219  *	name and find its value, then modify it according to the
3220  *	specification.
3221  *
3222  * Input:
3223  *	str		The string to parse
3224  *	ctxt		The context for the variable
3225  *	errnum		TRUE if undefined variables are an error
3226  *	lengthPtr	OUT: The length of the specification
3227  *	freePtr		OUT: Non-NULL if caller should free *freePtr
3228  *
3229  * Results:
3230  *	The (possibly-modified) value of the variable or var_Error if the
3231  *	specification is invalid. The length of the specification is
3232  *	placed in *lengthPtr (for invalid specifications, this is just
3233  *	2...?).
3234  *	If *freePtr is non-NULL then it's a pointer that the caller
3235  *	should pass to free() to free memory used by the result.
3236  *
3237  * Side Effects:
3238  *	None.
3239  *
3240  *-----------------------------------------------------------------------
3241  */
3242 /* coverity[+alloc : arg-*4] */
3243 char *
3244 Var_Parse(const char *str, GNode *ctxt, Boolean errnum, int *lengthPtr,
3245 	  void **freePtr)
3246 {
3247     const char	   *tstr;    	/* Pointer into str */
3248     Var	    	   *v;	    	/* Variable in invocation */
3249     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
3250     char	    endc;    	/* Ending character when variable in parens
3251 				 * or braces */
3252     char	    startc=0;	/* Starting character when variable in parens
3253 				 * or braces */
3254     int		    vlen;	/* Length of variable name */
3255     const char 	   *start;	/* Points to original start of str */
3256     char	   *nstr;	/* New string, used during expansion */
3257     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
3258 				 * expanding it in a non-local context. This
3259 				 * is done to support dynamic sources. The
3260 				 * result is just the invocation, unaltered */
3261     Var_Parse_State parsestate; /* Flags passed to helper functions */
3262 
3263     *freePtr = NULL;
3264     dynamic = FALSE;
3265     start = str;
3266     parsestate.oneBigWord = FALSE;
3267     parsestate.varSpace = ' ';	/* word separator */
3268 
3269     if (str[1] != PROPEN && str[1] != BROPEN) {
3270 	/*
3271 	 * If it's not bounded by braces of some sort, life is much simpler.
3272 	 * We just need to check for the first character and return the
3273 	 * value if it exists.
3274 	 */
3275 	char	  name[2];
3276 
3277 	name[0] = str[1];
3278 	name[1] = '\0';
3279 
3280 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3281 	if (v == (Var *)NIL) {
3282 	    *lengthPtr = 2;
3283 
3284 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
3285 		/*
3286 		 * If substituting a local variable in a non-local context,
3287 		 * assume it's for dynamic source stuff. We have to handle
3288 		 * this specially and return the longhand for the variable
3289 		 * with the dollar sign escaped so it makes it back to the
3290 		 * caller. Only four of the local variables are treated
3291 		 * specially as they are the only four that will be set
3292 		 * when dynamic sources are expanded.
3293 		 */
3294 		switch (str[1]) {
3295 		    case '@':
3296 			return UNCONST("$(.TARGET)");
3297 		    case '%':
3298 			return UNCONST("$(.ARCHIVE)");
3299 		    case '*':
3300 			return UNCONST("$(.PREFIX)");
3301 		    case '!':
3302 			return UNCONST("$(.MEMBER)");
3303 		}
3304 	    }
3305 	    /*
3306 	     * Error
3307 	     */
3308 	    return (errnum ? var_Error : varNoError);
3309 	} else {
3310 	    haveModifier = FALSE;
3311 	    tstr = &str[1];
3312 	    endc = str[1];
3313 	}
3314     } else if (str[1] == '\0') {
3315 	*lengthPtr = 1;
3316 	return (errnum ? var_Error : varNoError);
3317     } else {
3318 	Buffer buf;	/* Holds the variable name */
3319 
3320 	startc = str[1];
3321 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
3322 	buf = Buf_Init(0);
3323 
3324 	/*
3325 	 * Skip to the end character or a colon, whichever comes first.
3326 	 */
3327 	for (tstr = str + 2;
3328 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
3329 	     tstr++)
3330 	{
3331 	    /*
3332 	     * A variable inside a variable, expand
3333 	     */
3334 	    if (*tstr == '$') {
3335 		int rlen;
3336 		void *freeIt;
3337 		char *rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
3338 		if (rval != NULL) {
3339 		    Buf_AddBytes(buf, strlen(rval), (Byte *)rval);
3340 		}
3341 		if (freeIt)
3342 		    free(freeIt);
3343 		tstr += rlen - 1;
3344 	    }
3345 	    else
3346 		Buf_AddByte(buf, (Byte)*tstr);
3347 	}
3348 	if (*tstr == ':') {
3349 	    haveModifier = TRUE;
3350 	} else if (*tstr != '\0') {
3351 	    haveModifier = FALSE;
3352 	} else {
3353 	    /*
3354 	     * If we never did find the end character, return NULL
3355 	     * right now, setting the length to be the distance to
3356 	     * the end of the string, since that's what make does.
3357 	     */
3358 	    *lengthPtr = tstr - str;
3359 	    Buf_Destroy(buf, TRUE);
3360 	    return (var_Error);
3361 	}
3362 	Buf_AddByte(buf, (Byte)'\0');
3363 	str = Buf_GetAll(buf, NULL);
3364 	vlen = strlen(str);
3365 
3366 	/*
3367 	 * At this point, str points into newly allocated memory from
3368 	 * buf, containing only the name of the variable.
3369 	 *
3370 	 * start and tstr point into the const string that was pointed
3371 	 * to by the original value of the str parameter.  start points
3372 	 * to the '$' at the beginning of the string, while tstr points
3373 	 * to the char just after the end of the variable name -- this
3374 	 * will be '\0', ':', PRCLOSE, or BRCLOSE.
3375 	 */
3376 
3377 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
3378 	if ((v == (Var *)NIL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
3379 	    (vlen == 2) && (str[1] == 'F' || str[1] == 'D'))
3380 	{
3381 	    /*
3382 	     * Check for bogus D and F forms of local variables since we're
3383 	     * in a local context and the name is the right length.
3384 	     */
3385 	    switch(*str) {
3386 		case '@':
3387 		case '%':
3388 		case '*':
3389 		case '!':
3390 		case '>':
3391 		case '<':
3392 		{
3393 		    char    vname[2];
3394 		    char    *val;
3395 
3396 		    /*
3397 		     * Well, it's local -- go look for it.
3398 		     */
3399 		    vname[0] = *str;
3400 		    vname[1] = '\0';
3401 		    v = VarFind(vname, ctxt, 0);
3402 
3403 		    if (v != (Var *)NIL) {
3404 			/*
3405 			 * No need for nested expansion or anything, as we're
3406 			 * the only one who sets these things and we sure don't
3407 			 * but nested invocations in them...
3408 			 */
3409 			val = (char *)Buf_GetAll(v->val, NULL);
3410 
3411 			if (str[1] == 'D') {
3412 			    val = VarModify(ctxt, &parsestate, val, VarHead,
3413 					    NULL);
3414 			} else {
3415 			    val = VarModify(ctxt, &parsestate, val, VarTail,
3416 					    NULL);
3417 			}
3418 			/*
3419 			 * Resulting string is dynamically allocated, so
3420 			 * tell caller to free it.
3421 			 */
3422 			*freePtr = val;
3423 			*lengthPtr = tstr-start+1;
3424 			Buf_Destroy(buf, TRUE);
3425 			VarFreeEnv(v, TRUE);
3426 			return(val);
3427 		    }
3428 		    break;
3429 		}
3430 	    }
3431 	}
3432 
3433 	if (v == (Var *)NIL) {
3434 	    if (((vlen == 1) ||
3435 		 (((vlen == 2) && (str[1] == 'F' ||
3436 					 str[1] == 'D')))) &&
3437 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3438 	    {
3439 		/*
3440 		 * If substituting a local variable in a non-local context,
3441 		 * assume it's for dynamic source stuff. We have to handle
3442 		 * this specially and return the longhand for the variable
3443 		 * with the dollar sign escaped so it makes it back to the
3444 		 * caller. Only four of the local variables are treated
3445 		 * specially as they are the only four that will be set
3446 		 * when dynamic sources are expanded.
3447 		 */
3448 		switch (*str) {
3449 		    case '@':
3450 		    case '%':
3451 		    case '*':
3452 		    case '!':
3453 			dynamic = TRUE;
3454 			break;
3455 		}
3456 	    } else if ((vlen > 2) && (*str == '.') &&
3457 		       isupper((unsigned char) str[1]) &&
3458 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
3459 	    {
3460 		int	len;
3461 
3462 		len = vlen - 1;
3463 		if ((strncmp(str, ".TARGET", len) == 0) ||
3464 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
3465 		    (strncmp(str, ".PREFIX", len) == 0) ||
3466 		    (strncmp(str, ".MEMBER", len) == 0))
3467 		{
3468 		    dynamic = TRUE;
3469 		}
3470 	    }
3471 
3472 	    if (!haveModifier) {
3473 		/*
3474 		 * No modifiers -- have specification length so we can return
3475 		 * now.
3476 		 */
3477 		*lengthPtr = tstr - start + 1;
3478 		if (dynamic) {
3479 		    char *pstr = estrndup(start, *lengthPtr);
3480 		    *freePtr = pstr;
3481 		    Buf_Destroy(buf, TRUE);
3482 		    return(pstr);
3483 		} else {
3484 		    Buf_Destroy(buf, TRUE);
3485 		    return (errnum ? var_Error : varNoError);
3486 		}
3487 	    } else {
3488 		/*
3489 		 * Still need to get to the end of the variable specification,
3490 		 * so kludge up a Var structure for the modifications
3491 		 */
3492 		v = emalloc(sizeof(Var));
3493 		v->name = UNCONST(str);
3494 		v->val = Buf_Init(1);
3495 		v->flags = VAR_JUNK;
3496 		Buf_Destroy(buf, FALSE);
3497 	    }
3498 	} else
3499 	    Buf_Destroy(buf, TRUE);
3500     }
3501 
3502     if (v->flags & VAR_IN_USE) {
3503 	Fatal("Variable %s is recursive.", v->name);
3504 	/*NOTREACHED*/
3505     } else {
3506 	v->flags |= VAR_IN_USE;
3507     }
3508     /*
3509      * Before doing any modification, we have to make sure the value
3510      * has been fully expanded. If it looks like recursion might be
3511      * necessary (there's a dollar sign somewhere in the variable's value)
3512      * we just call Var_Subst to do any other substitutions that are
3513      * necessary. Note that the value returned by Var_Subst will have
3514      * been dynamically-allocated, so it will need freeing when we
3515      * return.
3516      */
3517     nstr = (char *)Buf_GetAll(v->val, NULL);
3518     if (strchr(nstr, '$') != NULL) {
3519 	nstr = Var_Subst(NULL, nstr, ctxt, errnum);
3520 	*freePtr = nstr;
3521     }
3522 
3523     v->flags &= ~VAR_IN_USE;
3524 
3525     if ((nstr != NULL) && haveModifier) {
3526 	int used;
3527 	/*
3528 	 * Skip initial colon.
3529 	 */
3530 	tstr++;
3531 
3532 	nstr = ApplyModifiers(nstr, tstr, startc, endc,
3533 			      v, ctxt, errnum, &used, freePtr);
3534 	tstr += used;
3535     }
3536     if (*tstr) {
3537 	*lengthPtr = tstr - start + 1;
3538     } else {
3539 	*lengthPtr = tstr - start;
3540     }
3541 
3542     if (v->flags & VAR_FROM_ENV) {
3543 	Boolean	  destroy = FALSE;
3544 
3545 	if (nstr != (char *)Buf_GetAll(v->val, NULL)) {
3546 	    destroy = TRUE;
3547 	} else {
3548 	    /*
3549 	     * Returning the value unmodified, so tell the caller to free
3550 	     * the thing.
3551 	     */
3552 	    *freePtr = nstr;
3553 	}
3554 	VarFreeEnv(v, destroy);
3555     } else if (v->flags & VAR_JUNK) {
3556 	/*
3557 	 * Perform any free'ing needed and set *freePtr to NULL so the caller
3558 	 * doesn't try to free a static pointer.
3559 	 * If VAR_KEEP is also set then we want to keep str as is.
3560 	 */
3561 	if (!(v->flags & VAR_KEEP)) {
3562 	    if (*freePtr) {
3563 		free(nstr);
3564 		*freePtr = NULL;
3565 	    }
3566 	    if (dynamic) {
3567 		nstr = estrndup(start, *lengthPtr);
3568 		*freePtr = nstr;
3569 	    } else {
3570 		nstr = var_Error;
3571 	    }
3572 	}
3573 	if (nstr != (char *)Buf_GetAll(v->val, NULL))
3574 	    Buf_Destroy(v->val, TRUE);
3575 	free(v->name);
3576 	free(v);
3577     }
3578     return (nstr);
3579 }
3580 
3581 /*-
3582  *-----------------------------------------------------------------------
3583  * Var_Subst  --
3584  *	Substitute for all variables in the given string in the given context
3585  *	If undefErr is TRUE, Parse_Error will be called when an undefined
3586  *	variable is encountered.
3587  *
3588  * Input:
3589  *	var		Named variable || NULL for all
3590  *	str		the string which to substitute
3591  *	ctxt		the context wherein to find variables
3592  *	undefErr	TRUE if undefineds are an error
3593  *
3594  * Results:
3595  *	The resulting string.
3596  *
3597  * Side Effects:
3598  *	None. The old string must be freed by the caller
3599  *-----------------------------------------------------------------------
3600  */
3601 char *
3602 Var_Subst(const char *var, const char *str, GNode *ctxt, Boolean undefErr)
3603 {
3604     Buffer  	  buf;	    	    /* Buffer for forming things */
3605     char    	  *val;		    /* Value to substitute for a variable */
3606     int	    	  length;   	    /* Length of the variable invocation */
3607     Boolean	  trailingBslash;   /* variable ends in \ */
3608     void 	  *freeIt = NULL;    /* Set if it should be freed */
3609     static Boolean errorReported;   /* Set true if an error has already
3610 				     * been reported to prevent a plethora
3611 				     * of messages when recursing */
3612 
3613     buf = Buf_Init(0);
3614     errorReported = FALSE;
3615     trailingBslash = FALSE;
3616 
3617     while (*str) {
3618 	if (*str == '\n' && trailingBslash)
3619 	    Buf_AddByte(buf, ' ');
3620 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
3621 	    /*
3622 	     * A dollar sign may be escaped either with another dollar sign.
3623 	     * In such a case, we skip over the escape character and store the
3624 	     * dollar sign into the buffer directly.
3625 	     */
3626 	    str++;
3627 	    Buf_AddByte(buf, (Byte)*str);
3628 	    str++;
3629 	} else if (*str != '$') {
3630 	    /*
3631 	     * Skip as many characters as possible -- either to the end of
3632 	     * the string or to the next dollar sign (variable invocation).
3633 	     */
3634 	    const char  *cp;
3635 
3636 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
3637 		continue;
3638 	    Buf_AddBytes(buf, str - cp, (const Byte *)cp);
3639 	} else {
3640 	    if (var != NULL) {
3641 		int expand;
3642 		for (;;) {
3643 		    if (str[1] == '\0') {
3644 			/* A trailing $ is kind of a special case */
3645 			Buf_AddByte(buf, str[0]);
3646 			str++;
3647 			expand = FALSE;
3648 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
3649 			if (str[1] != *var || strlen(var) > 1) {
3650 			    Buf_AddBytes(buf, 2, (const Byte *)str);
3651 			    str += 2;
3652 			    expand = FALSE;
3653 			}
3654 			else
3655 			    expand = TRUE;
3656 			break;
3657 		    }
3658 		    else {
3659 			const char *p;
3660 
3661 			/*
3662 			 * Scan up to the end of the variable name.
3663 			 */
3664 			for (p = &str[2]; *p &&
3665 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
3666 			    if (*p == '$')
3667 				break;
3668 			/*
3669 			 * A variable inside the variable. We cannot expand
3670 			 * the external variable yet, so we try again with
3671 			 * the nested one
3672 			 */
3673 			if (*p == '$') {
3674 			    Buf_AddBytes(buf, p - str, (const Byte *)str);
3675 			    str = p;
3676 			    continue;
3677 			}
3678 
3679 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
3680 			    var[p - str - 2] != '\0') {
3681 			    /*
3682 			     * Not the variable we want to expand, scan
3683 			     * until the next variable
3684 			     */
3685 			    for (;*p != '$' && *p != '\0'; p++)
3686 				continue;
3687 			    Buf_AddBytes(buf, p - str, (const Byte *)str);
3688 			    str = p;
3689 			    expand = FALSE;
3690 			}
3691 			else
3692 			    expand = TRUE;
3693 			break;
3694 		    }
3695 		}
3696 		if (!expand)
3697 		    continue;
3698 	    }
3699 
3700 	    val = Var_Parse(str, ctxt, undefErr, &length, &freeIt);
3701 
3702 	    /*
3703 	     * When we come down here, val should either point to the
3704 	     * value of this variable, suitably modified, or be NULL.
3705 	     * Length should be the total length of the potential
3706 	     * variable invocation (from $ to end character...)
3707 	     */
3708 	    if (val == var_Error || val == varNoError) {
3709 		/*
3710 		 * If performing old-time variable substitution, skip over
3711 		 * the variable and continue with the substitution. Otherwise,
3712 		 * store the dollar sign and advance str so we continue with
3713 		 * the string...
3714 		 */
3715 		if (oldVars) {
3716 		    str += length;
3717 		} else if (undefErr) {
3718 		    /*
3719 		     * If variable is undefined, complain and skip the
3720 		     * variable. The complaint will stop us from doing anything
3721 		     * when the file is parsed.
3722 		     */
3723 		    if (!errorReported) {
3724 			Parse_Error(PARSE_FATAL,
3725 				     "Undefined variable \"%.*s\"",length,str);
3726 		    }
3727 		    str += length;
3728 		    errorReported = TRUE;
3729 		} else {
3730 		    Buf_AddByte(buf, (Byte)*str);
3731 		    str += 1;
3732 		}
3733 	    } else {
3734 		/*
3735 		 * We've now got a variable structure to store in. But first,
3736 		 * advance the string pointer.
3737 		 */
3738 		str += length;
3739 
3740 		/*
3741 		 * Copy all the characters from the variable value straight
3742 		 * into the new string.
3743 		 */
3744 		length = strlen(val);
3745 		Buf_AddBytes(buf, length, (Byte *)val);
3746 		trailingBslash = length > 0 && val[length - 1] == '\\';
3747 	    }
3748 	    if (freeIt) {
3749 		free(freeIt);
3750 		freeIt = NULL;
3751 	    }
3752 	}
3753     }
3754 
3755     Buf_AddByte(buf, '\0');
3756     val = (char *)Buf_GetAll(buf, NULL);
3757     Buf_Destroy(buf, FALSE);
3758     return (val);
3759 }
3760 
3761 /*-
3762  *-----------------------------------------------------------------------
3763  * Var_GetTail --
3764  *	Return the tail from each of a list of words. Used to set the
3765  *	System V local variables.
3766  *
3767  * Input:
3768  *	file		Filename to modify
3769  *
3770  * Results:
3771  *	The resulting string.
3772  *
3773  * Side Effects:
3774  *	None.
3775  *
3776  *-----------------------------------------------------------------------
3777  */
3778 #if 0
3779 char *
3780 Var_GetTail(char *file)
3781 {
3782     return(VarModify(file, VarTail, NULL));
3783 }
3784 
3785 /*-
3786  *-----------------------------------------------------------------------
3787  * Var_GetHead --
3788  *	Find the leading components of a (list of) filename(s).
3789  *	XXX: VarHead does not replace foo by ., as (sun) System V make
3790  *	does.
3791  *
3792  * Input:
3793  *	file		Filename to manipulate
3794  *
3795  * Results:
3796  *	The leading components.
3797  *
3798  * Side Effects:
3799  *	None.
3800  *
3801  *-----------------------------------------------------------------------
3802  */
3803 char *
3804 Var_GetHead(char *file)
3805 {
3806     return(VarModify(file, VarHead, NULL));
3807 }
3808 #endif
3809 
3810 /*-
3811  *-----------------------------------------------------------------------
3812  * Var_Init --
3813  *	Initialize the module
3814  *
3815  * Results:
3816  *	None
3817  *
3818  * Side Effects:
3819  *	The VAR_CMD and VAR_GLOBAL contexts are created
3820  *-----------------------------------------------------------------------
3821  */
3822 void
3823 Var_Init(void)
3824 {
3825     VAR_GLOBAL = Targ_NewGN("Global");
3826     VAR_CMD = Targ_NewGN("Command");
3827 
3828 }
3829 
3830 
3831 void
3832 Var_End(void)
3833 {
3834 }
3835 
3836 
3837 /****************** PRINT DEBUGGING INFO *****************/
3838 static void
3839 VarPrintVar(ClientData vp)
3840 {
3841     Var    *v = (Var *)vp;
3842     fprintf(debug_file, "%-16s = %s\n", v->name, (char *)Buf_GetAll(v->val, NULL));
3843 }
3844 
3845 /*-
3846  *-----------------------------------------------------------------------
3847  * Var_Dump --
3848  *	print all variables in a context
3849  *-----------------------------------------------------------------------
3850  */
3851 void
3852 Var_Dump(GNode *ctxt)
3853 {
3854     Hash_Search search;
3855     Hash_Entry *h;
3856 
3857     for (h = Hash_EnumFirst(&ctxt->context, &search);
3858 	 h != NULL;
3859 	 h = Hash_EnumNext(&search)) {
3860 	    VarPrintVar(Hash_GetValue(h));
3861     }
3862 }
3863