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var.c revision 1.168
      1 /*	$NetBSD: var.c,v 1.168 2012/04/24 20:26:58 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 1.168 2012/04/24 20:26:58 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 1.168 2012/04/24 20:26:58 sjg Exp $");
     80 #endif
     81 #endif /* not lint */
     82 #endif
     83 
     84 /*-
     85  * var.c --
     86  *	Variable-handling functions
     87  *
     88  * Interface:
     89  *	Var_Set		    Set the value of a variable in the given
     90  *			    context. The variable is created if it doesn't
     91  *			    yet exist. The value and variable name need not
     92  *			    be preserved.
     93  *
     94  *	Var_Append	    Append more characters to an existing variable
     95  *			    in the given context. The variable needn't
     96  *			    exist already -- it will be created if it doesn't.
     97  *			    A space is placed between the old value and the
     98  *			    new one.
     99  *
    100  *	Var_Exists	    See if a variable exists.
    101  *
    102  *	Var_Value 	    Return the value of a variable in a context or
    103  *			    NULL if the variable is undefined.
    104  *
    105  *	Var_Subst 	    Substitute named variable, or all variables if
    106  *			    NULL in a string using
    107  *			    the given context as the top-most one. If the
    108  *			    third argument is non-zero, Parse_Error is
    109  *			    called if any variables are undefined.
    110  *
    111  *	Var_Parse 	    Parse a variable expansion from a string and
    112  *			    return the result and the number of characters
    113  *			    consumed.
    114  *
    115  *	Var_Delete	    Delete a variable in a context.
    116  *
    117  *	Var_Init  	    Initialize this module.
    118  *
    119  * Debugging:
    120  *	Var_Dump  	    Print out all variables defined in the given
    121  *			    context.
    122  *
    123  * XXX: There's a lot of duplication in these functions.
    124  */
    125 
    126 #include    <sys/stat.h>
    127 #ifndef NO_REGEX
    128 #include    <sys/types.h>
    129 #include    <regex.h>
    130 #endif
    131 #include    <ctype.h>
    132 #include    <inttypes.h>
    133 #include    <stdlib.h>
    134 #include    <limits.h>
    135 #include    <time.h>
    136 
    137 #include    "make.h"
    138 #include    "buf.h"
    139 #include    "dir.h"
    140 #include    "job.h"
    141 
    142 /*
    143  * This is a harmless return value for Var_Parse that can be used by Var_Subst
    144  * to determine if there was an error in parsing -- easier than returning
    145  * a flag, as things outside this module don't give a hoot.
    146  */
    147 char 	var_Error[] = "";
    148 
    149 /*
    150  * Similar to var_Error, but returned when the 'errnum' flag for Var_Parse is
    151  * set false. Why not just use a constant? Well, gcc likes to condense
    152  * identical string instances...
    153  */
    154 static char	varNoError[] = "";
    155 
    156 /*
    157  * Internally, variables are contained in four different contexts.
    158  *	1) the environment. They may not be changed. If an environment
    159  *	    variable is appended-to, the result is placed in the global
    160  *	    context.
    161  *	2) the global context. Variables set in the Makefile are located in
    162  *	    the global context. It is the penultimate context searched when
    163  *	    substituting.
    164  *	3) the command-line context. All variables set on the command line
    165  *	   are placed in this context. They are UNALTERABLE once placed here.
    166  *	4) the local context. Each target has associated with it a context
    167  *	   list. On this list are located the structures describing such
    168  *	   local variables as $(@) and $(*)
    169  * The four contexts are searched in the reverse order from which they are
    170  * listed.
    171  */
    172 GNode          *VAR_GLOBAL;   /* variables from the makefile */
    173 GNode          *VAR_CMD;      /* variables defined on the command-line */
    174 
    175 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
    176 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
    177 #define FIND_ENV  	0x4   /* look in the environment also */
    178 
    179 typedef struct Var {
    180     char          *name;	/* the variable's name */
    181     Buffer	  val;		/* its value */
    182     int		  flags;    	/* miscellaneous status flags */
    183 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
    184 				     * Used to avoid recursion */
    185 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
    186 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
    187 				     * should be destroyed when done with
    188 				     * it. Used by Var_Parse for undefined,
    189 				     * modified variables */
    190 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
    191 				     * a use for it in some modifier and
    192 				     * the value is therefore valid */
    193 #define VAR_EXPORTED	16 	    /* Variable is exported */
    194 #define VAR_REEXPORT	32	    /* Indicate if var needs re-export.
    195 				     * This would be true if it contains $'s
    196 				     */
    197 #define VAR_FROM_CMD	64 	    /* Variable came from command line */
    198 }  Var;
    199 
    200 /*
    201  * Exporting vars is expensive so skip it if we can
    202  */
    203 #define VAR_EXPORTED_NONE	0
    204 #define VAR_EXPORTED_YES	1
    205 #define VAR_EXPORTED_ALL	2
    206 static int var_exportedVars = VAR_EXPORTED_NONE;
    207 /*
    208  * We pass this to Var_Export when doing the initial export
    209  * or after updating an exported var.
    210  */
    211 #define VAR_EXPORT_PARENT 1
    212 
    213 /* Var*Pattern flags */
    214 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
    215 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
    216 #define VAR_SUB_MATCHED	0x04	/* There was a match */
    217 #define VAR_MATCH_START	0x08	/* Match at start of word */
    218 #define VAR_MATCH_END	0x10	/* Match at end of word */
    219 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
    220 
    221 /* Var_Set flags */
    222 #define VAR_NO_EXPORT	0x01	/* do not export */
    223 
    224 typedef struct {
    225     /*
    226      * The following fields are set by Var_Parse() when it
    227      * encounters modifiers that need to keep state for use by
    228      * subsequent modifiers within the same variable expansion.
    229      */
    230     Byte	varSpace;	/* Word separator in expansions */
    231     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
    232 				 * single big word, even if it contains
    233 				 * embedded spaces (as opposed to the
    234 				 * usual behaviour of treating it as
    235 				 * several space-separated words). */
    236 } Var_Parse_State;
    237 
    238 /* struct passed as 'void *' to VarSubstitute() for ":S/lhs/rhs/",
    239  * to VarSYSVMatch() for ":lhs=rhs". */
    240 typedef struct {
    241     const char   *lhs;	    /* String to match */
    242     int		  leftLen; /* Length of string */
    243     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
    244     int		  rightLen; /* Length of replacement */
    245     int		  flags;
    246 } VarPattern;
    247 
    248 /* struct passed as 'void *' to VarLoopExpand() for ":@tvar@str@" */
    249 typedef struct {
    250     GNode	*ctxt;		/* variable context */
    251     char	*tvar;		/* name of temp var */
    252     int		tvarLen;
    253     char	*str;		/* string to expand */
    254     int		strLen;
    255     int		errnum;		/* errnum for not defined */
    256 } VarLoop_t;
    257 
    258 #ifndef NO_REGEX
    259 /* struct passed as 'void *' to VarRESubstitute() for ":C///" */
    260 typedef struct {
    261     regex_t	   re;
    262     int		   nsub;
    263     regmatch_t 	  *matches;
    264     char 	  *replace;
    265     int		   flags;
    266 } VarREPattern;
    267 #endif
    268 
    269 /* struct passed to VarSelectWords() for ":[start..end]" */
    270 typedef struct {
    271     int		start;		/* first word to select */
    272     int		end;		/* last word to select */
    273 } VarSelectWords_t;
    274 
    275 static Var *VarFind(const char *, GNode *, int);
    276 static void VarAdd(const char *, const char *, GNode *);
    277 static Boolean VarHead(GNode *, Var_Parse_State *,
    278 			char *, Boolean, Buffer *, void *);
    279 static Boolean VarTail(GNode *, Var_Parse_State *,
    280 			char *, Boolean, Buffer *, void *);
    281 static Boolean VarSuffix(GNode *, Var_Parse_State *,
    282 			char *, Boolean, Buffer *, void *);
    283 static Boolean VarRoot(GNode *, Var_Parse_State *,
    284 			char *, Boolean, Buffer *, void *);
    285 static Boolean VarMatch(GNode *, Var_Parse_State *,
    286 			char *, Boolean, Buffer *, void *);
    287 #ifdef SYSVVARSUB
    288 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
    289 			char *, Boolean, Buffer *, void *);
    290 #endif
    291 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
    292 			char *, Boolean, Buffer *, void *);
    293 #ifndef NO_REGEX
    294 static void VarREError(int, regex_t *, const char *);
    295 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
    296 			char *, Boolean, Buffer *, void *);
    297 #endif
    298 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
    299 			char *, Boolean, Buffer *, void *);
    300 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
    301 			char *, Boolean, Buffer *, void *);
    302 static char *VarGetPattern(GNode *, Var_Parse_State *,
    303 			   int, const char **, int, int *, int *,
    304 			   VarPattern *);
    305 static char *VarQuote(char *);
    306 static char *VarChangeCase(char *, int);
    307 static char *VarHash(char *);
    308 static char *VarModify(GNode *, Var_Parse_State *,
    309     const char *,
    310     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer *, void *),
    311     void *);
    312 static char *VarOrder(const char *, const char);
    313 static char *VarUniq(const char *);
    314 static int VarWordCompare(const void *, const void *);
    315 static void VarPrintVar(void *);
    316 
    317 #define BROPEN	'{'
    318 #define BRCLOSE	'}'
    319 #define PROPEN	'('
    320 #define PRCLOSE	')'
    321 
    322 /*-
    323  *-----------------------------------------------------------------------
    324  * VarFind --
    325  *	Find the given variable in the given context and any other contexts
    326  *	indicated.
    327  *
    328  * Input:
    329  *	name		name to find
    330  *	ctxt		context in which to find it
    331  *	flags		FIND_GLOBAL set means to look in the
    332  *			VAR_GLOBAL context as well. FIND_CMD set means
    333  *			to look in the VAR_CMD context also. FIND_ENV
    334  *			set means to look in the environment
    335  *
    336  * Results:
    337  *	A pointer to the structure describing the desired variable or
    338  *	NULL if the variable does not exist.
    339  *
    340  * Side Effects:
    341  *	None
    342  *-----------------------------------------------------------------------
    343  */
    344 static Var *
    345 VarFind(const char *name, GNode *ctxt, int flags)
    346 {
    347     Hash_Entry         	*var;
    348     Var			*v;
    349 
    350 	/*
    351 	 * If the variable name begins with a '.', it could very well be one of
    352 	 * the local ones.  We check the name against all the local variables
    353 	 * and substitute the short version in for 'name' if it matches one of
    354 	 * them.
    355 	 */
    356 	if (*name == '.' && isupper((unsigned char) name[1]))
    357 		switch (name[1]) {
    358 		case 'A':
    359 			if (!strcmp(name, ".ALLSRC"))
    360 				name = ALLSRC;
    361 			if (!strcmp(name, ".ARCHIVE"))
    362 				name = ARCHIVE;
    363 			break;
    364 		case 'I':
    365 			if (!strcmp(name, ".IMPSRC"))
    366 				name = IMPSRC;
    367 			break;
    368 		case 'M':
    369 			if (!strcmp(name, ".MEMBER"))
    370 				name = MEMBER;
    371 			break;
    372 		case 'O':
    373 			if (!strcmp(name, ".OODATE"))
    374 				name = OODATE;
    375 			break;
    376 		case 'P':
    377 			if (!strcmp(name, ".PREFIX"))
    378 				name = PREFIX;
    379 			break;
    380 		case 'T':
    381 			if (!strcmp(name, ".TARGET"))
    382 				name = TARGET;
    383 			break;
    384 		}
    385 #ifdef notyet
    386     /* for compatibility with gmake */
    387     if (name[0] == '^' && name[1] == '\0')
    388 	    name = ALLSRC;
    389 #endif
    390 
    391     /*
    392      * First look for the variable in the given context. If it's not there,
    393      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
    394      * depending on the FIND_* flags in 'flags'
    395      */
    396     var = Hash_FindEntry(&ctxt->context, name);
    397 
    398     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
    399 	var = Hash_FindEntry(&VAR_CMD->context, name);
    400     }
    401     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
    402 	(ctxt != VAR_GLOBAL))
    403     {
    404 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
    405     }
    406     if ((var == NULL) && (flags & FIND_ENV)) {
    407 	char *env;
    408 
    409 	if ((env = getenv(name)) != NULL) {
    410 	    int		len;
    411 
    412 	    v = bmake_malloc(sizeof(Var));
    413 	    v->name = bmake_strdup(name);
    414 
    415 	    len = strlen(env);
    416 
    417 	    Buf_Init(&v->val, len + 1);
    418 	    Buf_AddBytes(&v->val, len, env);
    419 
    420 	    v->flags = VAR_FROM_ENV;
    421 	    return (v);
    422 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
    423 		   (ctxt != VAR_GLOBAL))
    424 	{
    425 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
    426 	    if (var == NULL) {
    427 		return NULL;
    428 	    } else {
    429 		return ((Var *)Hash_GetValue(var));
    430 	    }
    431 	} else {
    432 	    return NULL;
    433 	}
    434     } else if (var == NULL) {
    435 	return NULL;
    436     } else {
    437 	return ((Var *)Hash_GetValue(var));
    438     }
    439 }
    440 
    441 /*-
    442  *-----------------------------------------------------------------------
    443  * VarFreeEnv  --
    444  *	If the variable is an environment variable, free it
    445  *
    446  * Input:
    447  *	v		the variable
    448  *	destroy		true if the value buffer should be destroyed.
    449  *
    450  * Results:
    451  *	1 if it is an environment variable 0 ow.
    452  *
    453  * Side Effects:
    454  *	The variable is free'ed if it is an environent variable.
    455  *-----------------------------------------------------------------------
    456  */
    457 static Boolean
    458 VarFreeEnv(Var *v, Boolean destroy)
    459 {
    460     if ((v->flags & VAR_FROM_ENV) == 0)
    461 	return FALSE;
    462     free(v->name);
    463     Buf_Destroy(&v->val, destroy);
    464     free(v);
    465     return TRUE;
    466 }
    467 
    468 /*-
    469  *-----------------------------------------------------------------------
    470  * VarAdd  --
    471  *	Add a new variable of name name and value val to the given context
    472  *
    473  * Input:
    474  *	name		name of variable to add
    475  *	val		value to set it to
    476  *	ctxt		context in which to set it
    477  *
    478  * Results:
    479  *	None
    480  *
    481  * Side Effects:
    482  *	The new variable is placed at the front of the given context
    483  *	The name and val arguments are duplicated so they may
    484  *	safely be freed.
    485  *-----------------------------------------------------------------------
    486  */
    487 static void
    488 VarAdd(const char *name, const char *val, GNode *ctxt)
    489 {
    490     Var   	  *v;
    491     int		  len;
    492     Hash_Entry    *h;
    493 
    494     v = bmake_malloc(sizeof(Var));
    495 
    496     len = val ? strlen(val) : 0;
    497     Buf_Init(&v->val, len+1);
    498     Buf_AddBytes(&v->val, len, val);
    499 
    500     v->flags = 0;
    501 
    502     h = Hash_CreateEntry(&ctxt->context, name, NULL);
    503     Hash_SetValue(h, v);
    504     v->name = h->name;
    505     if (DEBUG(VAR)) {
    506 	fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
    507     }
    508 }
    509 
    510 /*-
    511  *-----------------------------------------------------------------------
    512  * Var_Delete --
    513  *	Remove a variable from a context.
    514  *
    515  * Results:
    516  *	None.
    517  *
    518  * Side Effects:
    519  *	The Var structure is removed and freed.
    520  *
    521  *-----------------------------------------------------------------------
    522  */
    523 void
    524 Var_Delete(const char *name, GNode *ctxt)
    525 {
    526     Hash_Entry 	  *ln;
    527 
    528     ln = Hash_FindEntry(&ctxt->context, name);
    529     if (DEBUG(VAR)) {
    530 	fprintf(debug_file, "%s:delete %s%s\n",
    531 	    ctxt->name, name, ln ? "" : " (not found)");
    532     }
    533     if (ln != NULL) {
    534 	Var 	  *v;
    535 
    536 	v = (Var *)Hash_GetValue(ln);
    537 	if ((v->flags & VAR_EXPORTED)) {
    538 	    unsetenv(v->name);
    539 	}
    540 	if (strcmp(MAKE_EXPORTED, v->name) == 0) {
    541 	    var_exportedVars = VAR_EXPORTED_NONE;
    542 	}
    543 	if (v->name != ln->name)
    544 		free(v->name);
    545 	Hash_DeleteEntry(&ctxt->context, ln);
    546 	Buf_Destroy(&v->val, TRUE);
    547 	free(v);
    548     }
    549 }
    550 
    551 
    552 /*
    553  * Export a var.
    554  * We ignore make internal variables (those which start with '.')
    555  * Also we jump through some hoops to avoid calling setenv
    556  * more than necessary since it can leak.
    557  * We only manipulate flags of vars if 'parent' is set.
    558  */
    559 static int
    560 Var_Export1(const char *name, int parent)
    561 {
    562     char tmp[BUFSIZ];
    563     Var *v;
    564     char *val = NULL;
    565     int n;
    566 
    567     if (*name == '.')
    568 	return 0;			/* skip internals */
    569     if (!name[1]) {
    570 	/*
    571 	 * A single char.
    572 	 * If it is one of the vars that should only appear in
    573 	 * local context, skip it, else we can get Var_Subst
    574 	 * into a loop.
    575 	 */
    576 	switch (name[0]) {
    577 	case '@':
    578 	case '%':
    579 	case '*':
    580 	case '!':
    581 	    return 0;
    582 	}
    583     }
    584     v = VarFind(name, VAR_GLOBAL, 0);
    585     if (v == NULL) {
    586 	return 0;
    587     }
    588     if (!parent &&
    589 	(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
    590 	return 0;			/* nothing to do */
    591     }
    592     val = Buf_GetAll(&v->val, NULL);
    593     if (strchr(val, '$')) {
    594 	if (parent) {
    595 	    /*
    596 	     * Flag this as something we need to re-export.
    597 	     * No point actually exporting it now though,
    598 	     * the child can do it at the last minute.
    599 	     */
    600 	    v->flags |= (VAR_EXPORTED|VAR_REEXPORT);
    601 	    return 1;
    602 	}
    603 	if (v->flags & VAR_IN_USE) {
    604 	    /*
    605 	     * We recursed while exporting in a child.
    606 	     * This isn't going to end well, just skip it.
    607 	     */
    608 	    return 0;
    609 	}
    610 	n = snprintf(tmp, sizeof(tmp), "${%s}", name);
    611 	if (n < (int)sizeof(tmp)) {
    612 	    val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    613 	    setenv(name, val, 1);
    614 	    free(val);
    615 	}
    616     } else {
    617 	if (parent) {
    618 	    v->flags &= ~VAR_REEXPORT;	/* once will do */
    619 	}
    620 	if (parent || !(v->flags & VAR_EXPORTED)) {
    621 	    setenv(name, val, 1);
    622 	}
    623     }
    624     /*
    625      * This is so Var_Set knows to call Var_Export again...
    626      */
    627     if (parent) {
    628 	v->flags |= VAR_EXPORTED;
    629     }
    630     return 1;
    631 }
    632 
    633 /*
    634  * This gets called from our children.
    635  */
    636 void
    637 Var_ExportVars(void)
    638 {
    639     char tmp[BUFSIZ];
    640     Hash_Entry         	*var;
    641     Hash_Search 	state;
    642     Var *v;
    643     char *val;
    644     int n;
    645 
    646     if (VAR_EXPORTED_NONE == var_exportedVars)
    647 	return;
    648 
    649     if (VAR_EXPORTED_ALL == var_exportedVars) {
    650 	/*
    651 	 * Ouch! This is crazy...
    652 	 */
    653 	for (var = Hash_EnumFirst(&VAR_GLOBAL->context, &state);
    654 	     var != NULL;
    655 	     var = Hash_EnumNext(&state)) {
    656 	    v = (Var *)Hash_GetValue(var);
    657 	    Var_Export1(v->name, 0);
    658 	}
    659 	return;
    660     }
    661     /*
    662      * We have a number of exported vars,
    663      */
    664     n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
    665     if (n < (int)sizeof(tmp)) {
    666 	char **av;
    667 	char *as;
    668 	int ac;
    669 	int i;
    670 
    671 	val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    672 	av = brk_string(val, &ac, FALSE, &as);
    673 	for (i = 0; i < ac; i++) {
    674 	    Var_Export1(av[i], 0);
    675 	}
    676 	free(val);
    677 	free(as);
    678 	free(av);
    679     }
    680 }
    681 
    682 /*
    683  * This is called when .export is seen or
    684  * .MAKE.EXPORTED is modified.
    685  * It is also called when any exported var is modified.
    686  */
    687 void
    688 Var_Export(char *str, int isExport)
    689 {
    690     char *name;
    691     char *val;
    692     char **av;
    693     char *as;
    694     int track;
    695     int ac;
    696     int i;
    697 
    698     if (isExport && (!str || !str[0])) {
    699 	var_exportedVars = VAR_EXPORTED_ALL; /* use with caution! */
    700 	return;
    701     }
    702 
    703     if (strncmp(str, "-env", 4) == 0) {
    704 	track = 0;
    705 	str += 4;
    706     } else {
    707 	track = VAR_EXPORT_PARENT;
    708     }
    709     val = Var_Subst(NULL, str, VAR_GLOBAL, 0);
    710     av = brk_string(val, &ac, FALSE, &as);
    711     for (i = 0; i < ac; i++) {
    712 	name = av[i];
    713 	if (!name[1]) {
    714 	    /*
    715 	     * A single char.
    716 	     * If it is one of the vars that should only appear in
    717 	     * local context, skip it, else we can get Var_Subst
    718 	     * into a loop.
    719 	     */
    720 	    switch (name[0]) {
    721 	    case '@':
    722 	    case '%':
    723 	    case '*':
    724 	    case '!':
    725 		continue;
    726 	    }
    727 	}
    728 	if (Var_Export1(name, track)) {
    729 	    if (VAR_EXPORTED_ALL != var_exportedVars)
    730 		var_exportedVars = VAR_EXPORTED_YES;
    731 	    if (isExport && track) {
    732 		Var_Append(MAKE_EXPORTED, name, VAR_GLOBAL);
    733 	    }
    734 	}
    735     }
    736     free(val);
    737     free(as);
    738     free(av);
    739 }
    740 
    741 
    742 /*
    743  * This is called when .unexport[-env] is seen.
    744  */
    745 void
    746 Var_UnExport(char *str)
    747 {
    748     char tmp[BUFSIZ];
    749     char *vlist;
    750     char *cp;
    751     Boolean unexport_env;
    752     int n;
    753 
    754     if (!str || !str[0]) {
    755 	return; 			/* assert? */
    756     }
    757 
    758     vlist = NULL;
    759 
    760     str += 8;
    761     unexport_env = (strncmp(str, "-env", 4) == 0);
    762     if (unexport_env) {
    763 	extern char **environ;
    764 	static char **savenv;
    765 	char **newenv;
    766 
    767 	cp = getenv(MAKE_LEVEL);	/* we should preserve this */
    768 	if (environ == savenv) {
    769 	    /* we have been here before! */
    770 	    newenv = bmake_realloc(environ, 2 * sizeof(char *));
    771 	} else {
    772 	    if (savenv) {
    773 		free(savenv);
    774 		savenv = NULL;
    775 	    }
    776 	    newenv = bmake_malloc(2 * sizeof(char *));
    777 	}
    778 	if (!newenv)
    779 	    return;
    780 	/* Note: we cannot safely free() the original environ. */
    781 	environ = savenv = newenv;
    782 	newenv[0] = NULL;
    783 	newenv[1] = NULL;
    784 	setenv(MAKE_LEVEL, cp, 1);
    785     } else {
    786 	for (; *str != '\n' && isspace((unsigned char) *str); str++)
    787 	    continue;
    788 	if (str[0] && str[0] != '\n') {
    789 	    vlist = str;
    790 	}
    791     }
    792 
    793     if (!vlist) {
    794 	/* Using .MAKE.EXPORTED */
    795 	n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
    796 	if (n < (int)sizeof(tmp)) {
    797 	    vlist = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    798 	}
    799     }
    800     if (vlist) {
    801 	Var *v;
    802 	char **av;
    803 	char *as;
    804 	int ac;
    805 	int i;
    806 
    807 	av = brk_string(vlist, &ac, FALSE, &as);
    808 	for (i = 0; i < ac; i++) {
    809 	    v = VarFind(av[i], VAR_GLOBAL, 0);
    810 	    if (!v)
    811 		continue;
    812 	    if (!unexport_env &&
    813 		(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
    814 		unsetenv(v->name);
    815 	    }
    816 	    v->flags &= ~(VAR_EXPORTED|VAR_REEXPORT);
    817 	    /*
    818 	     * If we are unexporting a list,
    819 	     * remove each one from .MAKE.EXPORTED.
    820 	     * If we are removing them all,
    821 	     * just delete .MAKE.EXPORTED below.
    822 	     */
    823 	    if (vlist == str) {
    824 		n = snprintf(tmp, sizeof(tmp),
    825 			     "${" MAKE_EXPORTED ":N%s}", v->name);
    826 		if (n < (int)sizeof(tmp)) {
    827 		    cp = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    828 		    Var_Set(MAKE_EXPORTED, cp, VAR_GLOBAL, 0);
    829 		    free(cp);
    830 		}
    831 	    }
    832 	}
    833 	free(as);
    834 	free(av);
    835 	if (vlist != str) {
    836 	    Var_Delete(MAKE_EXPORTED, VAR_GLOBAL);
    837 	    free(vlist);
    838 	}
    839     }
    840 }
    841 
    842 /*-
    843  *-----------------------------------------------------------------------
    844  * Var_Set --
    845  *	Set the variable name to the value val in the given context.
    846  *
    847  * Input:
    848  *	name		name of variable to set
    849  *	val		value to give to the variable
    850  *	ctxt		context in which to set it
    851  *
    852  * Results:
    853  *	None.
    854  *
    855  * Side Effects:
    856  *	If the variable doesn't yet exist, a new record is created for it.
    857  *	Else the old value is freed and the new one stuck in its place
    858  *
    859  * Notes:
    860  *	The variable is searched for only in its context before being
    861  *	created in that context. I.e. if the context is VAR_GLOBAL,
    862  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
    863  *	VAR_CMD->context is searched. This is done to avoid the literally
    864  *	thousands of unnecessary strcmp's that used to be done to
    865  *	set, say, $(@) or $(<).
    866  *	If the context is VAR_GLOBAL though, we check if the variable
    867  *	was set in VAR_CMD from the command line and skip it if so.
    868  *-----------------------------------------------------------------------
    869  */
    870 void
    871 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
    872 {
    873     Var   *v;
    874     char *expanded_name = NULL;
    875 
    876     /*
    877      * We only look for a variable in the given context since anything set
    878      * here will override anything in a lower context, so there's not much
    879      * point in searching them all just to save a bit of memory...
    880      */
    881     if (strchr(name, '$') != NULL) {
    882 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
    883 	if (expanded_name[0] == 0) {
    884 	    if (DEBUG(VAR)) {
    885 		fprintf(debug_file, "Var_Set(\"%s\", \"%s\", ...) "
    886 			"name expands to empty string - ignored\n",
    887 			name, val);
    888 	    }
    889 	    free(expanded_name);
    890 	    return;
    891 	}
    892 	name = expanded_name;
    893     }
    894     if (ctxt == VAR_GLOBAL) {
    895 	v = VarFind(name, VAR_CMD, 0);
    896 	if (v != NULL) {
    897 	    if ((v->flags & VAR_FROM_CMD)) {
    898 		if (DEBUG(VAR)) {
    899 		    fprintf(debug_file, "%s:%s = %s ignored!\n", ctxt->name, name, val);
    900 		}
    901 		goto out;
    902 	    }
    903 	    VarFreeEnv(v, TRUE);
    904 	}
    905     }
    906     v = VarFind(name, ctxt, 0);
    907     if (v == NULL) {
    908 	VarAdd(name, val, ctxt);
    909     } else {
    910 	Buf_Empty(&v->val);
    911 	Buf_AddBytes(&v->val, strlen(val), val);
    912 
    913 	if (DEBUG(VAR)) {
    914 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
    915 	}
    916 	if ((v->flags & VAR_EXPORTED)) {
    917 	    Var_Export1(name, VAR_EXPORT_PARENT);
    918 	}
    919     }
    920     /*
    921      * Any variables given on the command line are automatically exported
    922      * to the environment (as per POSIX standard)
    923      */
    924     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
    925 	if (v == NULL) {
    926 	    /* we just added it */
    927 	    v = VarFind(name, ctxt, 0);
    928 	}
    929 	if (v != NULL)
    930 	    v->flags |= VAR_FROM_CMD;
    931 	/*
    932 	 * If requested, don't export these in the environment
    933 	 * individually.  We still put them in MAKEOVERRIDES so
    934 	 * that the command-line settings continue to override
    935 	 * Makefile settings.
    936 	 */
    937 	if (varNoExportEnv != TRUE)
    938 	    setenv(name, val, 1);
    939 
    940 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
    941     }
    942     /*
    943      * Another special case.
    944      * Several make's support this sort of mechanism for tracking
    945      * recursion - but each uses a different name.
    946      * We allow the makefiles to update .MAKE.LEVEL and ensure
    947      * children see a correctly incremented value.
    948      */
    949     if (ctxt == VAR_GLOBAL && strcmp(MAKE_LEVEL, name) == 0) {
    950 	char tmp[64];
    951 	int level;
    952 
    953 	level = atoi(val);
    954 	snprintf(tmp, sizeof(tmp), "%u", level + 1);
    955 	setenv(MAKE_LEVEL, tmp, 1);
    956     }
    957 
    958 
    959  out:
    960     if (expanded_name != NULL)
    961 	free(expanded_name);
    962     if (v != NULL)
    963 	VarFreeEnv(v, TRUE);
    964 }
    965 
    966 /*-
    967  *-----------------------------------------------------------------------
    968  * Var_Append --
    969  *	The variable of the given name has the given value appended to it in
    970  *	the given context.
    971  *
    972  * Input:
    973  *	name		name of variable to modify
    974  *	val		String to append to it
    975  *	ctxt		Context in which this should occur
    976  *
    977  * Results:
    978  *	None
    979  *
    980  * Side Effects:
    981  *	If the variable doesn't exist, it is created. Else the strings
    982  *	are concatenated (with a space in between).
    983  *
    984  * Notes:
    985  *	Only if the variable is being sought in the global context is the
    986  *	environment searched.
    987  *	XXX: Knows its calling circumstances in that if called with ctxt
    988  *	an actual target, it will only search that context since only
    989  *	a local variable could be being appended to. This is actually
    990  *	a big win and must be tolerated.
    991  *-----------------------------------------------------------------------
    992  */
    993 void
    994 Var_Append(const char *name, const char *val, GNode *ctxt)
    995 {
    996     Var		   *v;
    997     Hash_Entry	   *h;
    998     char *expanded_name = NULL;
    999 
   1000     if (strchr(name, '$') != NULL) {
   1001 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
   1002 	if (expanded_name[0] == 0) {
   1003 	    if (DEBUG(VAR)) {
   1004 		fprintf(debug_file, "Var_Append(\"%s\", \"%s\", ...) "
   1005 			"name expands to empty string - ignored\n",
   1006 			name, val);
   1007 	    }
   1008 	    free(expanded_name);
   1009 	    return;
   1010 	}
   1011 	name = expanded_name;
   1012     }
   1013 
   1014     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
   1015 
   1016     if (v == NULL) {
   1017 	VarAdd(name, val, ctxt);
   1018     } else {
   1019 	Buf_AddByte(&v->val, ' ');
   1020 	Buf_AddBytes(&v->val, strlen(val), val);
   1021 
   1022 	if (DEBUG(VAR)) {
   1023 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name,
   1024 		   Buf_GetAll(&v->val, NULL));
   1025 	}
   1026 
   1027 	if (v->flags & VAR_FROM_ENV) {
   1028 	    /*
   1029 	     * If the original variable came from the environment, we
   1030 	     * have to install it in the global context (we could place
   1031 	     * it in the environment, but then we should provide a way to
   1032 	     * export other variables...)
   1033 	     */
   1034 	    v->flags &= ~VAR_FROM_ENV;
   1035 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
   1036 	    Hash_SetValue(h, v);
   1037 	}
   1038     }
   1039     if (expanded_name != NULL)
   1040 	free(expanded_name);
   1041 }
   1042 
   1043 /*-
   1044  *-----------------------------------------------------------------------
   1045  * Var_Exists --
   1046  *	See if the given variable exists.
   1047  *
   1048  * Input:
   1049  *	name		Variable to find
   1050  *	ctxt		Context in which to start search
   1051  *
   1052  * Results:
   1053  *	TRUE if it does, FALSE if it doesn't
   1054  *
   1055  * Side Effects:
   1056  *	None.
   1057  *
   1058  *-----------------------------------------------------------------------
   1059  */
   1060 Boolean
   1061 Var_Exists(const char *name, GNode *ctxt)
   1062 {
   1063     Var		  *v;
   1064     char          *cp;
   1065 
   1066     if ((cp = strchr(name, '$')) != NULL) {
   1067 	cp = Var_Subst(NULL, name, ctxt, FALSE);
   1068     }
   1069     v = VarFind(cp ? cp : name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
   1070     if (cp != NULL) {
   1071 	free(cp);
   1072     }
   1073     if (v == NULL) {
   1074 	return(FALSE);
   1075     } else {
   1076 	(void)VarFreeEnv(v, TRUE);
   1077     }
   1078     return(TRUE);
   1079 }
   1080 
   1081 /*-
   1082  *-----------------------------------------------------------------------
   1083  * Var_Value --
   1084  *	Return the value of the named variable in the given context
   1085  *
   1086  * Input:
   1087  *	name		name to find
   1088  *	ctxt		context in which to search for it
   1089  *
   1090  * Results:
   1091  *	The value if the variable exists, NULL if it doesn't
   1092  *
   1093  * Side Effects:
   1094  *	None
   1095  *-----------------------------------------------------------------------
   1096  */
   1097 char *
   1098 Var_Value(const char *name, GNode *ctxt, char **frp)
   1099 {
   1100     Var            *v;
   1101 
   1102     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   1103     *frp = NULL;
   1104     if (v != NULL) {
   1105 	char *p = (Buf_GetAll(&v->val, NULL));
   1106 	if (VarFreeEnv(v, FALSE))
   1107 	    *frp = p;
   1108 	return p;
   1109     } else {
   1110 	return NULL;
   1111     }
   1112 }
   1113 
   1114 /*-
   1115  *-----------------------------------------------------------------------
   1116  * VarHead --
   1117  *	Remove the tail of the given word and place the result in the given
   1118  *	buffer.
   1119  *
   1120  * Input:
   1121  *	word		Word to trim
   1122  *	addSpace	True if need to add a space to the buffer
   1123  *			before sticking in the head
   1124  *	buf		Buffer in which to store it
   1125  *
   1126  * Results:
   1127  *	TRUE if characters were added to the buffer (a space needs to be
   1128  *	added to the buffer before the next word).
   1129  *
   1130  * Side Effects:
   1131  *	The trimmed word is added to the buffer.
   1132  *
   1133  *-----------------------------------------------------------------------
   1134  */
   1135 static Boolean
   1136 VarHead(GNode *ctx __unused, Var_Parse_State *vpstate,
   1137 	char *word, Boolean addSpace, Buffer *buf,
   1138 	void *dummy)
   1139 {
   1140     char *slash;
   1141 
   1142     slash = strrchr(word, '/');
   1143     if (slash != NULL) {
   1144 	if (addSpace && vpstate->varSpace) {
   1145 	    Buf_AddByte(buf, vpstate->varSpace);
   1146 	}
   1147 	*slash = '\0';
   1148 	Buf_AddBytes(buf, strlen(word), word);
   1149 	*slash = '/';
   1150 	return (TRUE);
   1151     } else {
   1152 	/*
   1153 	 * If no directory part, give . (q.v. the POSIX standard)
   1154 	 */
   1155 	if (addSpace && vpstate->varSpace)
   1156 	    Buf_AddByte(buf, vpstate->varSpace);
   1157 	Buf_AddByte(buf, '.');
   1158     }
   1159     return(dummy ? TRUE : TRUE);
   1160 }
   1161 
   1162 /*-
   1163  *-----------------------------------------------------------------------
   1164  * VarTail --
   1165  *	Remove the head of the given word and place the result in the given
   1166  *	buffer.
   1167  *
   1168  * Input:
   1169  *	word		Word to trim
   1170  *	addSpace	True if need to add a space to the buffer
   1171  *			before adding the tail
   1172  *	buf		Buffer in which to store it
   1173  *
   1174  * Results:
   1175  *	TRUE if characters were added to the buffer (a space needs to be
   1176  *	added to the buffer before the next word).
   1177  *
   1178  * Side Effects:
   1179  *	The trimmed word is added to the buffer.
   1180  *
   1181  *-----------------------------------------------------------------------
   1182  */
   1183 static Boolean
   1184 VarTail(GNode *ctx __unused, Var_Parse_State *vpstate,
   1185 	char *word, Boolean addSpace, Buffer *buf,
   1186 	void *dummy)
   1187 {
   1188     char *slash;
   1189 
   1190     if (addSpace && vpstate->varSpace) {
   1191 	Buf_AddByte(buf, vpstate->varSpace);
   1192     }
   1193 
   1194     slash = strrchr(word, '/');
   1195     if (slash != NULL) {
   1196 	*slash++ = '\0';
   1197 	Buf_AddBytes(buf, strlen(slash), slash);
   1198 	slash[-1] = '/';
   1199     } else {
   1200 	Buf_AddBytes(buf, strlen(word), word);
   1201     }
   1202     return (dummy ? TRUE : TRUE);
   1203 }
   1204 
   1205 /*-
   1206  *-----------------------------------------------------------------------
   1207  * VarSuffix --
   1208  *	Place the suffix of the given word in the given buffer.
   1209  *
   1210  * Input:
   1211  *	word		Word to trim
   1212  *	addSpace	TRUE if need to add a space before placing the
   1213  *			suffix in the buffer
   1214  *	buf		Buffer in which to store it
   1215  *
   1216  * Results:
   1217  *	TRUE if characters were added to the buffer (a space needs to be
   1218  *	added to the buffer before the next word).
   1219  *
   1220  * Side Effects:
   1221  *	The suffix from the word is placed in the buffer.
   1222  *
   1223  *-----------------------------------------------------------------------
   1224  */
   1225 static Boolean
   1226 VarSuffix(GNode *ctx __unused, Var_Parse_State *vpstate,
   1227 	  char *word, Boolean addSpace, Buffer *buf,
   1228 	  void *dummy)
   1229 {
   1230     char *dot;
   1231 
   1232     dot = strrchr(word, '.');
   1233     if (dot != NULL) {
   1234 	if (addSpace && vpstate->varSpace) {
   1235 	    Buf_AddByte(buf, vpstate->varSpace);
   1236 	}
   1237 	*dot++ = '\0';
   1238 	Buf_AddBytes(buf, strlen(dot), dot);
   1239 	dot[-1] = '.';
   1240 	addSpace = TRUE;
   1241     }
   1242     return (dummy ? addSpace : addSpace);
   1243 }
   1244 
   1245 /*-
   1246  *-----------------------------------------------------------------------
   1247  * VarRoot --
   1248  *	Remove the suffix of the given word and place the result in the
   1249  *	buffer.
   1250  *
   1251  * Input:
   1252  *	word		Word to trim
   1253  *	addSpace	TRUE if need to add a space to the buffer
   1254  *			before placing the root in it
   1255  *	buf		Buffer in which to store it
   1256  *
   1257  * Results:
   1258  *	TRUE if characters were added to the buffer (a space needs to be
   1259  *	added to the buffer before the next word).
   1260  *
   1261  * Side Effects:
   1262  *	The trimmed word is added to the buffer.
   1263  *
   1264  *-----------------------------------------------------------------------
   1265  */
   1266 static Boolean
   1267 VarRoot(GNode *ctx __unused, Var_Parse_State *vpstate,
   1268 	char *word, Boolean addSpace, Buffer *buf,
   1269 	void *dummy)
   1270 {
   1271     char *dot;
   1272 
   1273     if (addSpace && vpstate->varSpace) {
   1274 	Buf_AddByte(buf, vpstate->varSpace);
   1275     }
   1276 
   1277     dot = strrchr(word, '.');
   1278     if (dot != NULL) {
   1279 	*dot = '\0';
   1280 	Buf_AddBytes(buf, strlen(word), word);
   1281 	*dot = '.';
   1282     } else {
   1283 	Buf_AddBytes(buf, strlen(word), word);
   1284     }
   1285     return (dummy ? TRUE : TRUE);
   1286 }
   1287 
   1288 /*-
   1289  *-----------------------------------------------------------------------
   1290  * VarMatch --
   1291  *	Place the word in the buffer if it matches the given pattern.
   1292  *	Callback function for VarModify to implement the :M modifier.
   1293  *
   1294  * Input:
   1295  *	word		Word to examine
   1296  *	addSpace	TRUE if need to add a space to the buffer
   1297  *			before adding the word, if it matches
   1298  *	buf		Buffer in which to store it
   1299  *	pattern		Pattern the word must match
   1300  *
   1301  * Results:
   1302  *	TRUE if a space should be placed in the buffer before the next
   1303  *	word.
   1304  *
   1305  * Side Effects:
   1306  *	The word may be copied to the buffer.
   1307  *
   1308  *-----------------------------------------------------------------------
   1309  */
   1310 static Boolean
   1311 VarMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
   1312 	 char *word, Boolean addSpace, Buffer *buf,
   1313 	 void *pattern)
   1314 {
   1315     if (DEBUG(VAR))
   1316 	fprintf(debug_file, "VarMatch [%s] [%s]\n", word, (char *)pattern);
   1317     if (Str_Match(word, (char *)pattern)) {
   1318 	if (addSpace && vpstate->varSpace) {
   1319 	    Buf_AddByte(buf, vpstate->varSpace);
   1320 	}
   1321 	addSpace = TRUE;
   1322 	Buf_AddBytes(buf, strlen(word), word);
   1323     }
   1324     return(addSpace);
   1325 }
   1326 
   1327 #ifdef SYSVVARSUB
   1328 /*-
   1329  *-----------------------------------------------------------------------
   1330  * VarSYSVMatch --
   1331  *	Place the word in the buffer if it matches the given pattern.
   1332  *	Callback function for VarModify to implement the System V %
   1333  *	modifiers.
   1334  *
   1335  * Input:
   1336  *	word		Word to examine
   1337  *	addSpace	TRUE if need to add a space to the buffer
   1338  *			before adding the word, if it matches
   1339  *	buf		Buffer in which to store it
   1340  *	patp		Pattern the word must match
   1341  *
   1342  * Results:
   1343  *	TRUE if a space should be placed in the buffer before the next
   1344  *	word.
   1345  *
   1346  * Side Effects:
   1347  *	The word may be copied to the buffer.
   1348  *
   1349  *-----------------------------------------------------------------------
   1350  */
   1351 static Boolean
   1352 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
   1353 	     char *word, Boolean addSpace, Buffer *buf,
   1354 	     void *patp)
   1355 {
   1356     int len;
   1357     char *ptr;
   1358     VarPattern 	  *pat = (VarPattern *)patp;
   1359     char *varexp;
   1360 
   1361     if (addSpace && vpstate->varSpace)
   1362 	Buf_AddByte(buf, vpstate->varSpace);
   1363 
   1364     addSpace = TRUE;
   1365 
   1366     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
   1367         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
   1368 	Str_SYSVSubst(buf, varexp, ptr, len);
   1369 	free(varexp);
   1370     } else {
   1371 	Buf_AddBytes(buf, strlen(word), word);
   1372     }
   1373 
   1374     return(addSpace);
   1375 }
   1376 #endif
   1377 
   1378 
   1379 /*-
   1380  *-----------------------------------------------------------------------
   1381  * VarNoMatch --
   1382  *	Place the word in the buffer if it doesn't match the given pattern.
   1383  *	Callback function for VarModify to implement the :N modifier.
   1384  *
   1385  * Input:
   1386  *	word		Word to examine
   1387  *	addSpace	TRUE if need to add a space to the buffer
   1388  *			before adding the word, if it matches
   1389  *	buf		Buffer in which to store it
   1390  *	pattern		Pattern the word must match
   1391  *
   1392  * Results:
   1393  *	TRUE if a space should be placed in the buffer before the next
   1394  *	word.
   1395  *
   1396  * Side Effects:
   1397  *	The word may be copied to the buffer.
   1398  *
   1399  *-----------------------------------------------------------------------
   1400  */
   1401 static Boolean
   1402 VarNoMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
   1403 	   char *word, Boolean addSpace, Buffer *buf,
   1404 	   void *pattern)
   1405 {
   1406     if (!Str_Match(word, (char *)pattern)) {
   1407 	if (addSpace && vpstate->varSpace) {
   1408 	    Buf_AddByte(buf, vpstate->varSpace);
   1409 	}
   1410 	addSpace = TRUE;
   1411 	Buf_AddBytes(buf, strlen(word), word);
   1412     }
   1413     return(addSpace);
   1414 }
   1415 
   1416 
   1417 /*-
   1418  *-----------------------------------------------------------------------
   1419  * VarSubstitute --
   1420  *	Perform a string-substitution on the given word, placing the
   1421  *	result in the passed buffer.
   1422  *
   1423  * Input:
   1424  *	word		Word to modify
   1425  *	addSpace	True if space should be added before
   1426  *			other characters
   1427  *	buf		Buffer for result
   1428  *	patternp	Pattern for substitution
   1429  *
   1430  * Results:
   1431  *	TRUE if a space is needed before more characters are added.
   1432  *
   1433  * Side Effects:
   1434  *	None.
   1435  *
   1436  *-----------------------------------------------------------------------
   1437  */
   1438 static Boolean
   1439 VarSubstitute(GNode *ctx __unused, Var_Parse_State *vpstate,
   1440 	      char *word, Boolean addSpace, Buffer *buf,
   1441 	      void *patternp)
   1442 {
   1443     int  	wordLen;    /* Length of word */
   1444     char 	*cp;	    /* General pointer */
   1445     VarPattern	*pattern = (VarPattern *)patternp;
   1446 
   1447     wordLen = strlen(word);
   1448     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
   1449 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
   1450 	/*
   1451 	 * Still substituting -- break it down into simple anchored cases
   1452 	 * and if none of them fits, perform the general substitution case.
   1453 	 */
   1454 	if ((pattern->flags & VAR_MATCH_START) &&
   1455 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
   1456 		/*
   1457 		 * Anchored at start and beginning of word matches pattern
   1458 		 */
   1459 		if ((pattern->flags & VAR_MATCH_END) &&
   1460 		    (wordLen == pattern->leftLen)) {
   1461 			/*
   1462 			 * Also anchored at end and matches to the end (word
   1463 			 * is same length as pattern) add space and rhs only
   1464 			 * if rhs is non-null.
   1465 			 */
   1466 			if (pattern->rightLen != 0) {
   1467 			    if (addSpace && vpstate->varSpace) {
   1468 				Buf_AddByte(buf, vpstate->varSpace);
   1469 			    }
   1470 			    addSpace = TRUE;
   1471 			    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1472 			}
   1473 			pattern->flags |= VAR_SUB_MATCHED;
   1474 		} else if (pattern->flags & VAR_MATCH_END) {
   1475 		    /*
   1476 		     * Doesn't match to end -- copy word wholesale
   1477 		     */
   1478 		    goto nosub;
   1479 		} else {
   1480 		    /*
   1481 		     * Matches at start but need to copy in trailing characters
   1482 		     */
   1483 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
   1484 			if (addSpace && vpstate->varSpace) {
   1485 			    Buf_AddByte(buf, vpstate->varSpace);
   1486 			}
   1487 			addSpace = TRUE;
   1488 		    }
   1489 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1490 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
   1491 				 (word + pattern->leftLen));
   1492 		    pattern->flags |= VAR_SUB_MATCHED;
   1493 		}
   1494 	} else if (pattern->flags & VAR_MATCH_START) {
   1495 	    /*
   1496 	     * Had to match at start of word and didn't -- copy whole word.
   1497 	     */
   1498 	    goto nosub;
   1499 	} else if (pattern->flags & VAR_MATCH_END) {
   1500 	    /*
   1501 	     * Anchored at end, Find only place match could occur (leftLen
   1502 	     * characters from the end of the word) and see if it does. Note
   1503 	     * that because the $ will be left at the end of the lhs, we have
   1504 	     * to use strncmp.
   1505 	     */
   1506 	    cp = word + (wordLen - pattern->leftLen);
   1507 	    if ((cp >= word) &&
   1508 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
   1509 		/*
   1510 		 * Match found. If we will place characters in the buffer,
   1511 		 * add a space before hand as indicated by addSpace, then
   1512 		 * stuff in the initial, unmatched part of the word followed
   1513 		 * by the right-hand-side.
   1514 		 */
   1515 		if (((cp - word) + pattern->rightLen) != 0) {
   1516 		    if (addSpace && vpstate->varSpace) {
   1517 			Buf_AddByte(buf, vpstate->varSpace);
   1518 		    }
   1519 		    addSpace = TRUE;
   1520 		}
   1521 		Buf_AddBytes(buf, cp - word, word);
   1522 		Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1523 		pattern->flags |= VAR_SUB_MATCHED;
   1524 	    } else {
   1525 		/*
   1526 		 * Had to match at end and didn't. Copy entire word.
   1527 		 */
   1528 		goto nosub;
   1529 	    }
   1530 	} else {
   1531 	    /*
   1532 	     * Pattern is unanchored: search for the pattern in the word using
   1533 	     * String_FindSubstring, copying unmatched portions and the
   1534 	     * right-hand-side for each match found, handling non-global
   1535 	     * substitutions correctly, etc. When the loop is done, any
   1536 	     * remaining part of the word (word and wordLen are adjusted
   1537 	     * accordingly through the loop) is copied straight into the
   1538 	     * buffer.
   1539 	     * addSpace is set FALSE as soon as a space is added to the
   1540 	     * buffer.
   1541 	     */
   1542 	    Boolean done;
   1543 	    int origSize;
   1544 
   1545 	    done = FALSE;
   1546 	    origSize = Buf_Size(buf);
   1547 	    while (!done) {
   1548 		cp = Str_FindSubstring(word, pattern->lhs);
   1549 		if (cp != NULL) {
   1550 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
   1551 			Buf_AddByte(buf, vpstate->varSpace);
   1552 			addSpace = FALSE;
   1553 		    }
   1554 		    Buf_AddBytes(buf, cp-word, word);
   1555 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1556 		    wordLen -= (cp - word) + pattern->leftLen;
   1557 		    word = cp + pattern->leftLen;
   1558 		    if (wordLen == 0) {
   1559 			done = TRUE;
   1560 		    }
   1561 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
   1562 			done = TRUE;
   1563 		    }
   1564 		    pattern->flags |= VAR_SUB_MATCHED;
   1565 		} else {
   1566 		    done = TRUE;
   1567 		}
   1568 	    }
   1569 	    if (wordLen != 0) {
   1570 		if (addSpace && vpstate->varSpace) {
   1571 		    Buf_AddByte(buf, vpstate->varSpace);
   1572 		}
   1573 		Buf_AddBytes(buf, wordLen, word);
   1574 	    }
   1575 	    /*
   1576 	     * If added characters to the buffer, need to add a space
   1577 	     * before we add any more. If we didn't add any, just return
   1578 	     * the previous value of addSpace.
   1579 	     */
   1580 	    return ((Buf_Size(buf) != origSize) || addSpace);
   1581 	}
   1582 	return (addSpace);
   1583     }
   1584  nosub:
   1585     if (addSpace && vpstate->varSpace) {
   1586 	Buf_AddByte(buf, vpstate->varSpace);
   1587     }
   1588     Buf_AddBytes(buf, wordLen, word);
   1589     return(TRUE);
   1590 }
   1591 
   1592 #ifndef NO_REGEX
   1593 /*-
   1594  *-----------------------------------------------------------------------
   1595  * VarREError --
   1596  *	Print the error caused by a regcomp or regexec call.
   1597  *
   1598  * Results:
   1599  *	None.
   1600  *
   1601  * Side Effects:
   1602  *	An error gets printed.
   1603  *
   1604  *-----------------------------------------------------------------------
   1605  */
   1606 static void
   1607 VarREError(int errnum, regex_t *pat, const char *str)
   1608 {
   1609     char *errbuf;
   1610     int errlen;
   1611 
   1612     errlen = regerror(errnum, pat, 0, 0);
   1613     errbuf = bmake_malloc(errlen);
   1614     regerror(errnum, pat, errbuf, errlen);
   1615     Error("%s: %s", str, errbuf);
   1616     free(errbuf);
   1617 }
   1618 
   1619 
   1620 /*-
   1621  *-----------------------------------------------------------------------
   1622  * VarRESubstitute --
   1623  *	Perform a regex substitution on the given word, placing the
   1624  *	result in the passed buffer.
   1625  *
   1626  * Results:
   1627  *	TRUE if a space is needed before more characters are added.
   1628  *
   1629  * Side Effects:
   1630  *	None.
   1631  *
   1632  *-----------------------------------------------------------------------
   1633  */
   1634 static Boolean
   1635 VarRESubstitute(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
   1636 		char *word, Boolean addSpace, Buffer *buf,
   1637 		void *patternp)
   1638 {
   1639     VarREPattern *pat;
   1640     int xrv;
   1641     char *wp;
   1642     char *rp;
   1643     int added;
   1644     int flags = 0;
   1645 
   1646 #define MAYBE_ADD_SPACE()		\
   1647 	if (addSpace && !added)		\
   1648 	    Buf_AddByte(buf, ' ');	\
   1649 	added = 1
   1650 
   1651     added = 0;
   1652     wp = word;
   1653     pat = patternp;
   1654 
   1655     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
   1656 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
   1657 	xrv = REG_NOMATCH;
   1658     else {
   1659     tryagain:
   1660 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
   1661     }
   1662 
   1663     switch (xrv) {
   1664     case 0:
   1665 	pat->flags |= VAR_SUB_MATCHED;
   1666 	if (pat->matches[0].rm_so > 0) {
   1667 	    MAYBE_ADD_SPACE();
   1668 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
   1669 	}
   1670 
   1671 	for (rp = pat->replace; *rp; rp++) {
   1672 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
   1673 		MAYBE_ADD_SPACE();
   1674 		Buf_AddByte(buf,rp[1]);
   1675 		rp++;
   1676 	    }
   1677 	    else if ((*rp == '&') ||
   1678 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
   1679 		int n;
   1680 		const char *subbuf;
   1681 		int sublen;
   1682 		char errstr[3];
   1683 
   1684 		if (*rp == '&') {
   1685 		    n = 0;
   1686 		    errstr[0] = '&';
   1687 		    errstr[1] = '\0';
   1688 		} else {
   1689 		    n = rp[1] - '0';
   1690 		    errstr[0] = '\\';
   1691 		    errstr[1] = rp[1];
   1692 		    errstr[2] = '\0';
   1693 		    rp++;
   1694 		}
   1695 
   1696 		if (n > pat->nsub) {
   1697 		    Error("No subexpression %s", &errstr[0]);
   1698 		    subbuf = "";
   1699 		    sublen = 0;
   1700 		} else if ((pat->matches[n].rm_so == -1) &&
   1701 			   (pat->matches[n].rm_eo == -1)) {
   1702 		    Error("No match for subexpression %s", &errstr[0]);
   1703 		    subbuf = "";
   1704 		    sublen = 0;
   1705 	        } else {
   1706 		    subbuf = wp + pat->matches[n].rm_so;
   1707 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
   1708 		}
   1709 
   1710 		if (sublen > 0) {
   1711 		    MAYBE_ADD_SPACE();
   1712 		    Buf_AddBytes(buf, sublen, subbuf);
   1713 		}
   1714 	    } else {
   1715 		MAYBE_ADD_SPACE();
   1716 		Buf_AddByte(buf, *rp);
   1717 	    }
   1718 	}
   1719 	wp += pat->matches[0].rm_eo;
   1720 	if (pat->flags & VAR_SUB_GLOBAL) {
   1721 	    flags |= REG_NOTBOL;
   1722 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
   1723 		MAYBE_ADD_SPACE();
   1724 		Buf_AddByte(buf, *wp);
   1725 		wp++;
   1726 
   1727 	    }
   1728 	    if (*wp)
   1729 		goto tryagain;
   1730 	}
   1731 	if (*wp) {
   1732 	    MAYBE_ADD_SPACE();
   1733 	    Buf_AddBytes(buf, strlen(wp), wp);
   1734 	}
   1735 	break;
   1736     default:
   1737 	VarREError(xrv, &pat->re, "Unexpected regex error");
   1738        /* fall through */
   1739     case REG_NOMATCH:
   1740 	if (*wp) {
   1741 	    MAYBE_ADD_SPACE();
   1742 	    Buf_AddBytes(buf,strlen(wp),wp);
   1743 	}
   1744 	break;
   1745     }
   1746     return(addSpace||added);
   1747 }
   1748 #endif
   1749 
   1750 
   1751 
   1752 /*-
   1753  *-----------------------------------------------------------------------
   1754  * VarLoopExpand --
   1755  *	Implements the :@<temp>@<string>@ modifier of ODE make.
   1756  *	We set the temp variable named in pattern.lhs to word and expand
   1757  *	pattern.rhs storing the result in the passed buffer.
   1758  *
   1759  * Input:
   1760  *	word		Word to modify
   1761  *	addSpace	True if space should be added before
   1762  *			other characters
   1763  *	buf		Buffer for result
   1764  *	pattern		Datafor substitution
   1765  *
   1766  * Results:
   1767  *	TRUE if a space is needed before more characters are added.
   1768  *
   1769  * Side Effects:
   1770  *	None.
   1771  *
   1772  *-----------------------------------------------------------------------
   1773  */
   1774 static Boolean
   1775 VarLoopExpand(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
   1776 	      char *word, Boolean addSpace, Buffer *buf,
   1777 	      void *loopp)
   1778 {
   1779     VarLoop_t	*loop = (VarLoop_t *)loopp;
   1780     char *s;
   1781     int slen;
   1782 
   1783     if (word && *word) {
   1784         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
   1785         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->errnum);
   1786         if (s != NULL && *s != '\0') {
   1787             if (addSpace && *s != '\n')
   1788                 Buf_AddByte(buf, ' ');
   1789             Buf_AddBytes(buf, (slen = strlen(s)), s);
   1790             addSpace = (slen > 0 && s[slen - 1] != '\n');
   1791             free(s);
   1792         }
   1793     }
   1794     return addSpace;
   1795 }
   1796 
   1797 
   1798 /*-
   1799  *-----------------------------------------------------------------------
   1800  * VarSelectWords --
   1801  *	Implements the :[start..end] modifier.
   1802  *	This is a special case of VarModify since we want to be able
   1803  *	to scan the list backwards if start > end.
   1804  *
   1805  * Input:
   1806  *	str		String whose words should be trimmed
   1807  *	seldata		words to select
   1808  *
   1809  * Results:
   1810  *	A string of all the words selected.
   1811  *
   1812  * Side Effects:
   1813  *	None.
   1814  *
   1815  *-----------------------------------------------------------------------
   1816  */
   1817 static char *
   1818 VarSelectWords(GNode *ctx __unused, Var_Parse_State *vpstate,
   1819 	       const char *str, VarSelectWords_t *seldata)
   1820 {
   1821     Buffer  	  buf;		    /* Buffer for the new string */
   1822     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
   1823 				     * buffer before adding the trimmed
   1824 				     * word */
   1825     char **av;			    /* word list */
   1826     char *as;			    /* word list memory */
   1827     int ac, i;
   1828     int start, end, step;
   1829 
   1830     Buf_Init(&buf, 0);
   1831     addSpace = FALSE;
   1832 
   1833     if (vpstate->oneBigWord) {
   1834 	/* fake what brk_string() would do if there were only one word */
   1835 	ac = 1;
   1836     	av = bmake_malloc((ac + 1) * sizeof(char *));
   1837 	as = bmake_strdup(str);
   1838 	av[0] = as;
   1839 	av[1] = NULL;
   1840     } else {
   1841 	av = brk_string(str, &ac, FALSE, &as);
   1842     }
   1843 
   1844     /*
   1845      * Now sanitize seldata.
   1846      * If seldata->start or seldata->end are negative, convert them to
   1847      * the positive equivalents (-1 gets converted to argc, -2 gets
   1848      * converted to (argc-1), etc.).
   1849      */
   1850     if (seldata->start < 0)
   1851 	seldata->start = ac + seldata->start + 1;
   1852     if (seldata->end < 0)
   1853 	seldata->end = ac + seldata->end + 1;
   1854 
   1855     /*
   1856      * We avoid scanning more of the list than we need to.
   1857      */
   1858     if (seldata->start > seldata->end) {
   1859 	start = MIN(ac, seldata->start) - 1;
   1860 	end = MAX(0, seldata->end - 1);
   1861 	step = -1;
   1862     } else {
   1863 	start = MAX(0, seldata->start - 1);
   1864 	end = MIN(ac, seldata->end);
   1865 	step = 1;
   1866     }
   1867 
   1868     for (i = start;
   1869 	 (step < 0 && i >= end) || (step > 0 && i < end);
   1870 	 i += step) {
   1871 	if (av[i] && *av[i]) {
   1872 	    if (addSpace && vpstate->varSpace) {
   1873 		Buf_AddByte(&buf, vpstate->varSpace);
   1874 	    }
   1875 	    Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   1876 	    addSpace = TRUE;
   1877 	}
   1878     }
   1879 
   1880     free(as);
   1881     free(av);
   1882 
   1883     return Buf_Destroy(&buf, FALSE);
   1884 }
   1885 
   1886 
   1887 /*-
   1888  * VarRealpath --
   1889  *	Replace each word with the result of realpath()
   1890  *	if successful.
   1891  */
   1892 static Boolean
   1893 VarRealpath(GNode *ctx __unused, Var_Parse_State *vpstate,
   1894 	    char *word, Boolean addSpace, Buffer *buf,
   1895 	    void *patternp __unused)
   1896 {
   1897 	struct stat st;
   1898 	char rbuf[MAXPATHLEN];
   1899 	char *rp;
   1900 
   1901 	if (addSpace && vpstate->varSpace) {
   1902 	    Buf_AddByte(buf, vpstate->varSpace);
   1903 	}
   1904 	addSpace = TRUE;
   1905 	rp = realpath(word, rbuf);
   1906 	if (rp && *rp == '/' && stat(rp, &st) == 0)
   1907 		word = rp;
   1908 
   1909 	Buf_AddBytes(buf, strlen(word), word);
   1910 	return(addSpace);
   1911 }
   1912 
   1913 /*-
   1914  *-----------------------------------------------------------------------
   1915  * VarModify --
   1916  *	Modify each of the words of the passed string using the given
   1917  *	function. Used to implement all modifiers.
   1918  *
   1919  * Input:
   1920  *	str		String whose words should be trimmed
   1921  *	modProc		Function to use to modify them
   1922  *	datum		Datum to pass it
   1923  *
   1924  * Results:
   1925  *	A string of all the words modified appropriately.
   1926  *
   1927  * Side Effects:
   1928  *	None.
   1929  *
   1930  *-----------------------------------------------------------------------
   1931  */
   1932 static char *
   1933 VarModify(GNode *ctx, Var_Parse_State *vpstate,
   1934     const char *str,
   1935     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
   1936 		       Boolean, Buffer *, void *),
   1937     void *datum)
   1938 {
   1939     Buffer  	  buf;		    /* Buffer for the new string */
   1940     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
   1941 				     * buffer before adding the trimmed
   1942 				     * word */
   1943     char **av;			    /* word list */
   1944     char *as;			    /* word list memory */
   1945     int ac, i;
   1946 
   1947     Buf_Init(&buf, 0);
   1948     addSpace = FALSE;
   1949 
   1950     if (vpstate->oneBigWord) {
   1951 	/* fake what brk_string() would do if there were only one word */
   1952 	ac = 1;
   1953     	av = bmake_malloc((ac + 1) * sizeof(char *));
   1954 	as = bmake_strdup(str);
   1955 	av[0] = as;
   1956 	av[1] = NULL;
   1957     } else {
   1958 	av = brk_string(str, &ac, FALSE, &as);
   1959     }
   1960 
   1961     for (i = 0; i < ac; i++) {
   1962 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, &buf, datum);
   1963     }
   1964 
   1965     free(as);
   1966     free(av);
   1967 
   1968     return Buf_Destroy(&buf, FALSE);
   1969 }
   1970 
   1971 
   1972 static int
   1973 VarWordCompare(const void *a, const void *b)
   1974 {
   1975 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
   1976 	return r;
   1977 }
   1978 
   1979 /*-
   1980  *-----------------------------------------------------------------------
   1981  * VarOrder --
   1982  *	Order the words in the string.
   1983  *
   1984  * Input:
   1985  *	str		String whose words should be sorted.
   1986  *	otype		How to order: s - sort, x - random.
   1987  *
   1988  * Results:
   1989  *	A string containing the words ordered.
   1990  *
   1991  * Side Effects:
   1992  *	None.
   1993  *
   1994  *-----------------------------------------------------------------------
   1995  */
   1996 static char *
   1997 VarOrder(const char *str, const char otype)
   1998 {
   1999     Buffer  	  buf;		    /* Buffer for the new string */
   2000     char **av;			    /* word list [first word does not count] */
   2001     char *as;			    /* word list memory */
   2002     int ac, i;
   2003 
   2004     Buf_Init(&buf, 0);
   2005 
   2006     av = brk_string(str, &ac, FALSE, &as);
   2007 
   2008     if (ac > 0)
   2009 	switch (otype) {
   2010 	case 's':	/* sort alphabetically */
   2011 	    qsort(av, ac, sizeof(char *), VarWordCompare);
   2012 	    break;
   2013 	case 'x':	/* randomize */
   2014 	{
   2015 	    int rndidx;
   2016 	    char *t;
   2017 
   2018 	    /*
   2019 	     * We will use [ac..2] range for mod factors. This will produce
   2020 	     * random numbers in [(ac-1)..0] interval, and minimal
   2021 	     * reasonable value for mod factor is 2 (the mod 1 will produce
   2022 	     * 0 with probability 1).
   2023 	     */
   2024 	    for (i = ac-1; i > 0; i--) {
   2025 		rndidx = random() % (i + 1);
   2026 		if (i != rndidx) {
   2027 		    t = av[i];
   2028 		    av[i] = av[rndidx];
   2029 		    av[rndidx] = t;
   2030 		}
   2031 	    }
   2032 	}
   2033 	} /* end of switch */
   2034 
   2035     for (i = 0; i < ac; i++) {
   2036 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   2037 	if (i != ac - 1)
   2038 	    Buf_AddByte(&buf, ' ');
   2039     }
   2040 
   2041     free(as);
   2042     free(av);
   2043 
   2044     return Buf_Destroy(&buf, FALSE);
   2045 }
   2046 
   2047 
   2048 /*-
   2049  *-----------------------------------------------------------------------
   2050  * VarUniq --
   2051  *	Remove adjacent duplicate words.
   2052  *
   2053  * Input:
   2054  *	str		String whose words should be sorted
   2055  *
   2056  * Results:
   2057  *	A string containing the resulting words.
   2058  *
   2059  * Side Effects:
   2060  *	None.
   2061  *
   2062  *-----------------------------------------------------------------------
   2063  */
   2064 static char *
   2065 VarUniq(const char *str)
   2066 {
   2067     Buffer	  buf;		    /* Buffer for new string */
   2068     char 	**av;		    /* List of words to affect */
   2069     char 	 *as;		    /* Word list memory */
   2070     int 	  ac, i, j;
   2071 
   2072     Buf_Init(&buf, 0);
   2073     av = brk_string(str, &ac, FALSE, &as);
   2074 
   2075     if (ac > 1) {
   2076 	for (j = 0, i = 1; i < ac; i++)
   2077 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
   2078 		av[j] = av[i];
   2079 	ac = j + 1;
   2080     }
   2081 
   2082     for (i = 0; i < ac; i++) {
   2083 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   2084 	if (i != ac - 1)
   2085 	    Buf_AddByte(&buf, ' ');
   2086     }
   2087 
   2088     free(as);
   2089     free(av);
   2090 
   2091     return Buf_Destroy(&buf, FALSE);
   2092 }
   2093 
   2094 
   2095 /*-
   2096  *-----------------------------------------------------------------------
   2097  * VarGetPattern --
   2098  *	Pass through the tstr looking for 1) escaped delimiters,
   2099  *	'$'s and backslashes (place the escaped character in
   2100  *	uninterpreted) and 2) unescaped $'s that aren't before
   2101  *	the delimiter (expand the variable substitution unless flags
   2102  *	has VAR_NOSUBST set).
   2103  *	Return the expanded string or NULL if the delimiter was missing
   2104  *	If pattern is specified, handle escaped ampersands, and replace
   2105  *	unescaped ampersands with the lhs of the pattern.
   2106  *
   2107  * Results:
   2108  *	A string of all the words modified appropriately.
   2109  *	If length is specified, return the string length of the buffer
   2110  *	If flags is specified and the last character of the pattern is a
   2111  *	$ set the VAR_MATCH_END bit of flags.
   2112  *
   2113  * Side Effects:
   2114  *	None.
   2115  *-----------------------------------------------------------------------
   2116  */
   2117 static char *
   2118 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate __unused,
   2119 	      int errnum, const char **tstr, int delim, int *flags,
   2120 	      int *length, VarPattern *pattern)
   2121 {
   2122     const char *cp;
   2123     char *rstr;
   2124     Buffer buf;
   2125     int junk;
   2126 
   2127     Buf_Init(&buf, 0);
   2128     if (length == NULL)
   2129 	length = &junk;
   2130 
   2131 #define IS_A_MATCH(cp, delim) \
   2132     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
   2133      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
   2134 
   2135     /*
   2136      * Skim through until the matching delimiter is found;
   2137      * pick up variable substitutions on the way. Also allow
   2138      * backslashes to quote the delimiter, $, and \, but don't
   2139      * touch other backslashes.
   2140      */
   2141     for (cp = *tstr; *cp && (*cp != delim); cp++) {
   2142 	if (IS_A_MATCH(cp, delim)) {
   2143 	    Buf_AddByte(&buf, cp[1]);
   2144 	    cp++;
   2145 	} else if (*cp == '$') {
   2146 	    if (cp[1] == delim) {
   2147 		if (flags == NULL)
   2148 		    Buf_AddByte(&buf, *cp);
   2149 		else
   2150 		    /*
   2151 		     * Unescaped $ at end of pattern => anchor
   2152 		     * pattern at end.
   2153 		     */
   2154 		    *flags |= VAR_MATCH_END;
   2155 	    } else {
   2156 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
   2157 		    char   *cp2;
   2158 		    int     len;
   2159 		    void   *freeIt;
   2160 
   2161 		    /*
   2162 		     * If unescaped dollar sign not before the
   2163 		     * delimiter, assume it's a variable
   2164 		     * substitution and recurse.
   2165 		     */
   2166 		    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
   2167 		    Buf_AddBytes(&buf, strlen(cp2), cp2);
   2168 		    if (freeIt)
   2169 			free(freeIt);
   2170 		    cp += len - 1;
   2171 		} else {
   2172 		    const char *cp2 = &cp[1];
   2173 
   2174 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
   2175 			/*
   2176 			 * Find the end of this variable reference
   2177 			 * and suck it in without further ado.
   2178 			 * It will be interperated later.
   2179 			 */
   2180 			int have = *cp2;
   2181 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
   2182 			int depth = 1;
   2183 
   2184 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
   2185 			    if (cp2[-1] != '\\') {
   2186 				if (*cp2 == have)
   2187 				    ++depth;
   2188 				if (*cp2 == want)
   2189 				    --depth;
   2190 			    }
   2191 			}
   2192 			Buf_AddBytes(&buf, cp2 - cp, cp);
   2193 			cp = --cp2;
   2194 		    } else
   2195 			Buf_AddByte(&buf, *cp);
   2196 		}
   2197 	    }
   2198 	}
   2199 	else if (pattern && *cp == '&')
   2200 	    Buf_AddBytes(&buf, pattern->leftLen, pattern->lhs);
   2201 	else
   2202 	    Buf_AddByte(&buf, *cp);
   2203     }
   2204 
   2205     if (*cp != delim) {
   2206 	*tstr = cp;
   2207 	*length = 0;
   2208 	return NULL;
   2209     }
   2210 
   2211     *tstr = ++cp;
   2212     *length = Buf_Size(&buf);
   2213     rstr = Buf_Destroy(&buf, FALSE);
   2214     if (DEBUG(VAR))
   2215 	fprintf(debug_file, "Modifier pattern: \"%s\"\n", rstr);
   2216     return rstr;
   2217 }
   2218 
   2219 /*-
   2220  *-----------------------------------------------------------------------
   2221  * VarQuote --
   2222  *	Quote shell meta-characters in the string
   2223  *
   2224  * Results:
   2225  *	The quoted string
   2226  *
   2227  * Side Effects:
   2228  *	None.
   2229  *
   2230  *-----------------------------------------------------------------------
   2231  */
   2232 static char *
   2233 VarQuote(char *str)
   2234 {
   2235 
   2236     Buffer  	  buf;
   2237     /* This should cover most shells :-( */
   2238     static const char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
   2239     const char	*newline;
   2240     size_t len, nlen;
   2241 
   2242     if ((newline = Shell_GetNewline()) == NULL)
   2243 	    newline = "\\\n";
   2244     nlen = strlen(newline);
   2245 
   2246     Buf_Init(&buf, 0);
   2247     while (*str != '\0') {
   2248 	if ((len = strcspn(str, meta)) != 0) {
   2249 	    Buf_AddBytes(&buf, len, str);
   2250 	    str += len;
   2251 	} else if (*str == '\n') {
   2252 	    Buf_AddBytes(&buf, nlen, newline);
   2253 	    ++str;
   2254 	} else {
   2255 	    Buf_AddByte(&buf, '\\');
   2256 	    Buf_AddByte(&buf, *str);
   2257 	    ++str;
   2258 	}
   2259     }
   2260     str = Buf_Destroy(&buf, FALSE);
   2261     if (DEBUG(VAR))
   2262 	fprintf(debug_file, "QuoteMeta: [%s]\n", str);
   2263     return str;
   2264 }
   2265 
   2266 /*-
   2267  *-----------------------------------------------------------------------
   2268  * VarHash --
   2269  *      Hash the string using the MurmurHash3 algorithm.
   2270  *      Output is computed using 32bit Little Endian arithmetic.
   2271  *
   2272  * Input:
   2273  *	str		String to modify
   2274  *
   2275  * Results:
   2276  *      Hash value of str, encoded as 8 hex digits.
   2277  *
   2278  * Side Effects:
   2279  *      None.
   2280  *
   2281  *-----------------------------------------------------------------------
   2282  */
   2283 static char *
   2284 VarHash(char *str)
   2285 {
   2286     static const char    hexdigits[16] = "0123456789abcdef";
   2287     Buffer         buf;
   2288     size_t         len, len2;
   2289     unsigned char  *ustr = (unsigned char *)str;
   2290     uint32_t       h, k, c1, c2;
   2291     int            done;
   2292 
   2293     done = 1;
   2294     h  = 0x971e137bU;
   2295     c1 = 0x95543787U;
   2296     c2 = 0x2ad7eb25U;
   2297     len2 = strlen(str);
   2298 
   2299     for (len = len2; len; ) {
   2300 	k = 0;
   2301 	switch (len) {
   2302 	default:
   2303 	    k = (ustr[3] << 24) | (ustr[2] << 16) | (ustr[1] << 8) | ustr[0];
   2304 	    len -= 4;
   2305 	    ustr += 4;
   2306 	    break;
   2307 	case 3:
   2308 	    k |= (ustr[2] << 16);
   2309 	case 2:
   2310 	    k |= (ustr[1] << 8);
   2311 	case 1:
   2312 	    k |= ustr[0];
   2313 	    len = 0;
   2314 	}
   2315 	c1 = c1 * 5 + 0x7b7d159cU;
   2316 	c2 = c2 * 5 + 0x6bce6396U;
   2317 	k *= c1;
   2318 	k = (k << 11) ^ (k >> 21);
   2319 	k *= c2;
   2320 	h = (h << 13) ^ (h >> 19);
   2321 	h = h * 5 + 0x52dce729U;
   2322 	h ^= k;
   2323    } while (!done);
   2324    h ^= len2;
   2325    h *= 0x85ebca6b;
   2326    h ^= h >> 13;
   2327    h *= 0xc2b2ae35;
   2328    h ^= h >> 16;
   2329 
   2330    Buf_Init(&buf, 0);
   2331    for (len = 0; len < 8; ++len) {
   2332        Buf_AddByte(&buf, hexdigits[h & 15]);
   2333        h >>= 4;
   2334    }
   2335 
   2336    return Buf_Destroy(&buf, FALSE);
   2337 }
   2338 
   2339 /*-
   2340  *-----------------------------------------------------------------------
   2341  * VarChangeCase --
   2342  *      Change the string to all uppercase or all lowercase
   2343  *
   2344  * Input:
   2345  *	str		String to modify
   2346  *	upper		TRUE -> uppercase, else lowercase
   2347  *
   2348  * Results:
   2349  *      The string with case changed
   2350  *
   2351  * Side Effects:
   2352  *      None.
   2353  *
   2354  *-----------------------------------------------------------------------
   2355  */
   2356 static char *
   2357 VarChangeCase(char *str, int upper)
   2358 {
   2359    Buffer         buf;
   2360    int            (*modProc)(int);
   2361 
   2362    modProc = (upper ? toupper : tolower);
   2363    Buf_Init(&buf, 0);
   2364    for (; *str ; str++) {
   2365        Buf_AddByte(&buf, modProc(*str));
   2366    }
   2367    return Buf_Destroy(&buf, FALSE);
   2368 }
   2369 
   2370 static char *
   2371 VarStrftime(const char *fmt, int zulu)
   2372 {
   2373     char buf[BUFSIZ];
   2374     time_t utc;
   2375 
   2376     time(&utc);
   2377     if (!*fmt)
   2378 	fmt = "%c";
   2379     strftime(buf, sizeof(buf), fmt, zulu ? gmtime(&utc) : localtime(&utc));
   2380 
   2381     buf[sizeof(buf) - 1] = '\0';
   2382     return bmake_strdup(buf);
   2383 }
   2384 
   2385 /*
   2386  * Now we need to apply any modifiers the user wants applied.
   2387  * These are:
   2388  *  	  :M<pattern>	words which match the given <pattern>.
   2389  *  			<pattern> is of the standard file
   2390  *  			wildcarding form.
   2391  *  	  :N<pattern>	words which do not match the given <pattern>.
   2392  *  	  :S<d><pat1><d><pat2><d>[1gW]
   2393  *  			Substitute <pat2> for <pat1> in the value
   2394  *  	  :C<d><pat1><d><pat2><d>[1gW]
   2395  *  			Substitute <pat2> for regex <pat1> in the value
   2396  *  	  :H		Substitute the head of each word
   2397  *  	  :T		Substitute the tail of each word
   2398  *  	  :E		Substitute the extension (minus '.') of
   2399  *  			each word
   2400  *  	  :R		Substitute the root of each word
   2401  *  			(pathname minus the suffix).
   2402  *	  :O		("Order") Alphabeticaly sort words in variable.
   2403  *	  :Ox		("intermiX") Randomize words in variable.
   2404  *	  :u		("uniq") Remove adjacent duplicate words.
   2405  *	  :tu		Converts the variable contents to uppercase.
   2406  *	  :tl		Converts the variable contents to lowercase.
   2407  *	  :ts[c]	Sets varSpace - the char used to
   2408  *			separate words to 'c'. If 'c' is
   2409  *			omitted then no separation is used.
   2410  *	  :tW		Treat the variable contents as a single
   2411  *			word, even if it contains spaces.
   2412  *			(Mnemonic: one big 'W'ord.)
   2413  *	  :tw		Treat the variable contents as multiple
   2414  *			space-separated words.
   2415  *			(Mnemonic: many small 'w'ords.)
   2416  *	  :[index]	Select a single word from the value.
   2417  *	  :[start..end]	Select multiple words from the value.
   2418  *	  :[*] or :[0]	Select the entire value, as a single
   2419  *			word.  Equivalent to :tW.
   2420  *	  :[@]		Select the entire value, as multiple
   2421  *			words.	Undoes the effect of :[*].
   2422  *			Equivalent to :tw.
   2423  *	  :[#]		Returns the number of words in the value.
   2424  *
   2425  *	  :?<true-value>:<false-value>
   2426  *			If the variable evaluates to true, return
   2427  *			true value, else return the second value.
   2428  *    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
   2429  *    			the invocation.
   2430  *	  :sh		Treat the current value as a command
   2431  *			to be run, new value is its output.
   2432  * The following added so we can handle ODE makefiles.
   2433  *	  :@<tmpvar>@<newval>@
   2434  *			Assign a temporary local variable <tmpvar>
   2435  *			to the current value of each word in turn
   2436  *			and replace each word with the result of
   2437  *			evaluating <newval>
   2438  *	  :D<newval>	Use <newval> as value if variable defined
   2439  *	  :U<newval>	Use <newval> as value if variable undefined
   2440  *	  :L		Use the name of the variable as the value.
   2441  *	  :P		Use the path of the node that has the same
   2442  *			name as the variable as the value.  This
   2443  *			basically includes an implied :L so that
   2444  *			the common method of refering to the path
   2445  *			of your dependent 'x' in a rule is to use
   2446  *			the form '${x:P}'.
   2447  *	  :!<cmd>!	Run cmd much the same as :sh run's the
   2448  *			current value of the variable.
   2449  * The ::= modifiers, actually assign a value to the variable.
   2450  * Their main purpose is in supporting modifiers of .for loop
   2451  * iterators and other obscure uses.  They always expand to
   2452  * nothing.  In a target rule that would otherwise expand to an
   2453  * empty line they can be preceded with @: to keep make happy.
   2454  * Eg.
   2455  *
   2456  * foo:	.USE
   2457  * .for i in ${.TARGET} ${.TARGET:R}.gz
   2458  * 	@: ${t::=$i}
   2459  *	@echo blah ${t:T}
   2460  * .endfor
   2461  *
   2462  *	  ::=<str>	Assigns <str> as the new value of variable.
   2463  *	  ::?=<str>	Assigns <str> as value of variable if
   2464  *			it was not already set.
   2465  *	  ::+=<str>	Appends <str> to variable.
   2466  *	  ::!=<cmd>	Assigns output of <cmd> as the new value of
   2467  *			variable.
   2468  */
   2469 
   2470 /* we now have some modifiers with long names */
   2471 #define STRMOD_MATCH(s, want, n) \
   2472     (strncmp(s, want, n) == 0 && (s[n] == endc || s[n] == ':'))
   2473 
   2474 static char *
   2475 ApplyModifiers(char *nstr, const char *tstr,
   2476 	       int startc, int endc,
   2477 	       Var *v, GNode *ctxt, Boolean errnum,
   2478 	       int *lengthPtr, void **freePtr)
   2479 {
   2480     const char 	   *start;
   2481     const char     *cp;    	/* Secondary pointer into str (place marker
   2482 				 * for tstr) */
   2483     char	   *newStr;	/* New value to return */
   2484     char	    termc;	/* Character which terminated scan */
   2485     int             cnt;	/* Used to count brace pairs when variable in
   2486 				 * in parens or braces */
   2487     char	delim;
   2488     int		modifier;	/* that we are processing */
   2489     Var_Parse_State parsestate; /* Flags passed to helper functions */
   2490 
   2491     delim = '\0';
   2492     parsestate.oneBigWord = FALSE;
   2493     parsestate.varSpace = ' ';	/* word separator */
   2494 
   2495     start = cp = tstr;
   2496 
   2497     while (*tstr && *tstr != endc) {
   2498 
   2499 	if (*tstr == '$') {
   2500 	    /*
   2501 	     * We may have some complex modifiers in a variable.
   2502 	     */
   2503 	    void *freeIt;
   2504 	    char *rval;
   2505 	    int rlen;
   2506 	    int c;
   2507 
   2508 	    rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
   2509 
   2510 	    /*
   2511 	     * If we have not parsed up to endc or ':',
   2512 	     * we are not interested.
   2513 	     */
   2514 	    if (rval != NULL && *rval &&
   2515 		(c = tstr[rlen]) != '\0' &&
   2516 		c != ':' &&
   2517 		c != endc) {
   2518 		if (freeIt)
   2519 		    free(freeIt);
   2520 		goto apply_mods;
   2521 	    }
   2522 
   2523 	    if (DEBUG(VAR)) {
   2524 		fprintf(debug_file, "Got '%s' from '%.*s'%.*s\n",
   2525 		       rval, rlen, tstr, rlen, tstr + rlen);
   2526 	    }
   2527 
   2528 	    tstr += rlen;
   2529 
   2530 	    if (rval != NULL && *rval) {
   2531 		int used;
   2532 
   2533 		nstr = ApplyModifiers(nstr, rval,
   2534 				      0, 0,
   2535 				      v, ctxt, errnum, &used, freePtr);
   2536 		if (nstr == var_Error
   2537 		    || (nstr == varNoError && errnum == 0)
   2538 		    || strlen(rval) != (size_t) used) {
   2539 		    if (freeIt)
   2540 			free(freeIt);
   2541 		    goto out;		/* error already reported */
   2542 		}
   2543 	    }
   2544 	    if (freeIt)
   2545 		free(freeIt);
   2546 	    if (*tstr == ':')
   2547 		tstr++;
   2548 	    else if (!*tstr && endc) {
   2549 		Error("Unclosed variable specification after complex modifier (expecting '%c') for %s", endc, v->name);
   2550 		goto out;
   2551 	    }
   2552 	    continue;
   2553 	}
   2554     apply_mods:
   2555 	if (DEBUG(VAR)) {
   2556 	    fprintf(debug_file, "Applying :%c to \"%s\"\n", *tstr, nstr);
   2557 	}
   2558 	newStr = var_Error;
   2559 	switch ((modifier = *tstr)) {
   2560 	case ':':
   2561 	    {
   2562 		if (tstr[1] == '=' ||
   2563 		    (tstr[2] == '=' &&
   2564 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
   2565 		    /*
   2566 		     * "::=", "::!=", "::+=", or "::?="
   2567 		     */
   2568 		    GNode *v_ctxt;		/* context where v belongs */
   2569 		    const char *emsg;
   2570 		    char *sv_name;
   2571 		    VarPattern	pattern;
   2572 		    int	how;
   2573 
   2574 		    if (v->name[0] == 0)
   2575 			goto bad_modifier;
   2576 
   2577 		    v_ctxt = ctxt;
   2578 		    sv_name = NULL;
   2579 		    ++tstr;
   2580 		    if (v->flags & VAR_JUNK) {
   2581 			/*
   2582 			 * We need to bmake_strdup() it incase
   2583 			 * VarGetPattern() recurses.
   2584 			 */
   2585 			sv_name = v->name;
   2586 			v->name = bmake_strdup(v->name);
   2587 		    } else if (ctxt != VAR_GLOBAL) {
   2588 			Var *gv = VarFind(v->name, ctxt, 0);
   2589 			if (gv == NULL)
   2590 			    v_ctxt = VAR_GLOBAL;
   2591 			else
   2592 			    VarFreeEnv(gv, TRUE);
   2593 		    }
   2594 
   2595 		    switch ((how = *tstr)) {
   2596 		    case '+':
   2597 		    case '?':
   2598 		    case '!':
   2599 			cp = &tstr[2];
   2600 			break;
   2601 		    default:
   2602 			cp = ++tstr;
   2603 			break;
   2604 		    }
   2605 		    delim = startc == PROPEN ? PRCLOSE : BRCLOSE;
   2606 		    pattern.flags = 0;
   2607 
   2608 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   2609 						&cp, delim, NULL,
   2610 						&pattern.rightLen,
   2611 						NULL);
   2612 		    if (v->flags & VAR_JUNK) {
   2613 			/* restore original name */
   2614 			free(v->name);
   2615 			v->name = sv_name;
   2616 		    }
   2617 		    if (pattern.rhs == NULL)
   2618 			goto cleanup;
   2619 
   2620 		    termc = *--cp;
   2621 		    delim = '\0';
   2622 
   2623 		    switch (how) {
   2624 		    case '+':
   2625 			Var_Append(v->name, pattern.rhs, v_ctxt);
   2626 			break;
   2627 		    case '!':
   2628 			newStr = Cmd_Exec(pattern.rhs, &emsg);
   2629 			if (emsg)
   2630 			    Error(emsg, nstr);
   2631 			else
   2632 			    Var_Set(v->name, newStr,  v_ctxt, 0);
   2633 			if (newStr)
   2634 			    free(newStr);
   2635 			break;
   2636 		    case '?':
   2637 			if ((v->flags & VAR_JUNK) == 0)
   2638 			    break;
   2639 			/* FALLTHROUGH */
   2640 		    default:
   2641 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
   2642 			break;
   2643 		    }
   2644 		    free(UNCONST(pattern.rhs));
   2645 		    newStr = var_Error;
   2646 		    break;
   2647 		}
   2648 		goto default_case; /* "::<unrecognised>" */
   2649 	    }
   2650 	case '@':
   2651 	    {
   2652 		VarLoop_t	loop;
   2653 		int flags = VAR_NOSUBST;
   2654 
   2655 		cp = ++tstr;
   2656 		delim = '@';
   2657 		if ((loop.tvar = VarGetPattern(ctxt, &parsestate, errnum,
   2658 					       &cp, delim,
   2659 					       &flags, &loop.tvarLen,
   2660 					       NULL)) == NULL)
   2661 		    goto cleanup;
   2662 
   2663 		if ((loop.str = VarGetPattern(ctxt, &parsestate, errnum,
   2664 					      &cp, delim,
   2665 					      &flags, &loop.strLen,
   2666 					      NULL)) == NULL)
   2667 		    goto cleanup;
   2668 
   2669 		termc = *cp;
   2670 		delim = '\0';
   2671 
   2672 		loop.errnum = errnum;
   2673 		loop.ctxt = ctxt;
   2674 		newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
   2675 				   &loop);
   2676 		free(loop.tvar);
   2677 		free(loop.str);
   2678 		break;
   2679 	    }
   2680 	case 'D':
   2681 	case 'U':
   2682 	    {
   2683 		Buffer  buf;    	/* Buffer for patterns */
   2684 		int	    wantit;	/* want data in buffer */
   2685 
   2686 		/*
   2687 		 * Pass through tstr looking for 1) escaped delimiters,
   2688 		 * '$'s and backslashes (place the escaped character in
   2689 		 * uninterpreted) and 2) unescaped $'s that aren't before
   2690 		 * the delimiter (expand the variable substitution).
   2691 		 * The result is left in the Buffer buf.
   2692 		 */
   2693 		Buf_Init(&buf, 0);
   2694 		for (cp = tstr + 1;
   2695 		     *cp != endc && *cp != ':' && *cp != '\0';
   2696 		     cp++) {
   2697 		    if ((*cp == '\\') &&
   2698 			((cp[1] == ':') ||
   2699 			 (cp[1] == '$') ||
   2700 			 (cp[1] == endc) ||
   2701 			 (cp[1] == '\\')))
   2702 			{
   2703 			    Buf_AddByte(&buf, cp[1]);
   2704 			    cp++;
   2705 			} else if (*cp == '$') {
   2706 			    /*
   2707 			     * If unescaped dollar sign, assume it's a
   2708 			     * variable substitution and recurse.
   2709 			     */
   2710 			    char    *cp2;
   2711 			    int	    len;
   2712 			    void    *freeIt;
   2713 
   2714 			    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
   2715 			    Buf_AddBytes(&buf, strlen(cp2), cp2);
   2716 			    if (freeIt)
   2717 				free(freeIt);
   2718 			    cp += len - 1;
   2719 			} else {
   2720 			    Buf_AddByte(&buf, *cp);
   2721 			}
   2722 		}
   2723 
   2724 		termc = *cp;
   2725 
   2726 		if (*tstr == 'U')
   2727 		    wantit = ((v->flags & VAR_JUNK) != 0);
   2728 		else
   2729 		    wantit = ((v->flags & VAR_JUNK) == 0);
   2730 		if ((v->flags & VAR_JUNK) != 0)
   2731 		    v->flags |= VAR_KEEP;
   2732 		if (wantit) {
   2733 		    newStr = Buf_Destroy(&buf, FALSE);
   2734 		} else {
   2735 		    newStr = nstr;
   2736 		    Buf_Destroy(&buf, TRUE);
   2737 		}
   2738 		break;
   2739 	    }
   2740 	case 'L':
   2741 	    {
   2742 		if ((v->flags & VAR_JUNK) != 0)
   2743 		    v->flags |= VAR_KEEP;
   2744 		newStr = bmake_strdup(v->name);
   2745 		cp = ++tstr;
   2746 		termc = *tstr;
   2747 		break;
   2748 	    }
   2749 	case 'P':
   2750 	    {
   2751 		GNode *gn;
   2752 
   2753 		if ((v->flags & VAR_JUNK) != 0)
   2754 		    v->flags |= VAR_KEEP;
   2755 		gn = Targ_FindNode(v->name, TARG_NOCREATE);
   2756 		if (gn == NULL || gn->type & OP_NOPATH) {
   2757 		    newStr = NULL;
   2758 		} else if (gn->path) {
   2759 		    newStr = bmake_strdup(gn->path);
   2760 		} else {
   2761 		    newStr = Dir_FindFile(v->name, Suff_FindPath(gn));
   2762 		}
   2763 		if (!newStr) {
   2764 		    newStr = bmake_strdup(v->name);
   2765 		}
   2766 		cp = ++tstr;
   2767 		termc = *tstr;
   2768 		break;
   2769 	    }
   2770 	case '!':
   2771 	    {
   2772 		const char *emsg;
   2773 		VarPattern 	    pattern;
   2774 		pattern.flags = 0;
   2775 
   2776 		delim = '!';
   2777 
   2778 		cp = ++tstr;
   2779 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   2780 						 &cp, delim,
   2781 						 NULL, &pattern.rightLen,
   2782 						 NULL)) == NULL)
   2783 		    goto cleanup;
   2784 		newStr = Cmd_Exec(pattern.rhs, &emsg);
   2785 		free(UNCONST(pattern.rhs));
   2786 		if (emsg)
   2787 		    Error(emsg, nstr);
   2788 		termc = *cp;
   2789 		delim = '\0';
   2790 		if (v->flags & VAR_JUNK) {
   2791 		    v->flags |= VAR_KEEP;
   2792 		}
   2793 		break;
   2794 	    }
   2795 	case '[':
   2796 	    {
   2797 		/*
   2798 		 * Look for the closing ']', recursively
   2799 		 * expanding any embedded variables.
   2800 		 *
   2801 		 * estr is a pointer to the expanded result,
   2802 		 * which we must free().
   2803 		 */
   2804 		char *estr;
   2805 
   2806 		cp = tstr+1; /* point to char after '[' */
   2807 		delim = ']'; /* look for closing ']' */
   2808 		estr = VarGetPattern(ctxt, &parsestate,
   2809 				     errnum, &cp, delim,
   2810 				     NULL, NULL, NULL);
   2811 		if (estr == NULL)
   2812 		    goto cleanup; /* report missing ']' */
   2813 		/* now cp points just after the closing ']' */
   2814 		delim = '\0';
   2815 		if (cp[0] != ':' && cp[0] != endc) {
   2816 		    /* Found junk after ']' */
   2817 		    free(estr);
   2818 		    goto bad_modifier;
   2819 		}
   2820 		if (estr[0] == '\0') {
   2821 		    /* Found empty square brackets in ":[]". */
   2822 		    free(estr);
   2823 		    goto bad_modifier;
   2824 		} else if (estr[0] == '#' && estr[1] == '\0') {
   2825 		    /* Found ":[#]" */
   2826 
   2827 		    /*
   2828 		     * We will need enough space for the decimal
   2829 		     * representation of an int.  We calculate the
   2830 		     * space needed for the octal representation,
   2831 		     * and add enough slop to cope with a '-' sign
   2832 		     * (which should never be needed) and a '\0'
   2833 		     * string terminator.
   2834 		     */
   2835 		    int newStrSize =
   2836 			(sizeof(int) * CHAR_BIT + 2) / 3 + 2;
   2837 
   2838 		    newStr = bmake_malloc(newStrSize);
   2839 		    if (parsestate.oneBigWord) {
   2840 			strncpy(newStr, "1", newStrSize);
   2841 		    } else {
   2842 			/* XXX: brk_string() is a rather expensive
   2843 			 * way of counting words. */
   2844 			char **av;
   2845 			char *as;
   2846 			int ac;
   2847 
   2848 			av = brk_string(nstr, &ac, FALSE, &as);
   2849 			snprintf(newStr, newStrSize,  "%d", ac);
   2850 			free(as);
   2851 			free(av);
   2852 		    }
   2853 		    termc = *cp;
   2854 		    free(estr);
   2855 		    break;
   2856 		} else if (estr[0] == '*' && estr[1] == '\0') {
   2857 		    /* Found ":[*]" */
   2858 		    parsestate.oneBigWord = TRUE;
   2859 		    newStr = nstr;
   2860 		    termc = *cp;
   2861 		    free(estr);
   2862 		    break;
   2863 		} else if (estr[0] == '@' && estr[1] == '\0') {
   2864 		    /* Found ":[@]" */
   2865 		    parsestate.oneBigWord = FALSE;
   2866 		    newStr = nstr;
   2867 		    termc = *cp;
   2868 		    free(estr);
   2869 		    break;
   2870 		} else {
   2871 		    /*
   2872 		     * We expect estr to contain a single
   2873 		     * integer for :[N], or two integers
   2874 		     * separated by ".." for :[start..end].
   2875 		     */
   2876 		    char *ep;
   2877 
   2878 		    VarSelectWords_t seldata = { 0, 0 };
   2879 
   2880 		    seldata.start = strtol(estr, &ep, 0);
   2881 		    if (ep == estr) {
   2882 			/* Found junk instead of a number */
   2883 			free(estr);
   2884 			goto bad_modifier;
   2885 		    } else if (ep[0] == '\0') {
   2886 			/* Found only one integer in :[N] */
   2887 			seldata.end = seldata.start;
   2888 		    } else if (ep[0] == '.' && ep[1] == '.' &&
   2889 			       ep[2] != '\0') {
   2890 			/* Expecting another integer after ".." */
   2891 			ep += 2;
   2892 			seldata.end = strtol(ep, &ep, 0);
   2893 			if (ep[0] != '\0') {
   2894 			    /* Found junk after ".." */
   2895 			    free(estr);
   2896 			    goto bad_modifier;
   2897 			}
   2898 		    } else {
   2899 			/* Found junk instead of ".." */
   2900 			free(estr);
   2901 			goto bad_modifier;
   2902 		    }
   2903 		    /*
   2904 		     * Now seldata is properly filled in,
   2905 		     * but we still have to check for 0 as
   2906 		     * a special case.
   2907 		     */
   2908 		    if (seldata.start == 0 && seldata.end == 0) {
   2909 			/* ":[0]" or perhaps ":[0..0]" */
   2910 			parsestate.oneBigWord = TRUE;
   2911 			newStr = nstr;
   2912 			termc = *cp;
   2913 			free(estr);
   2914 			break;
   2915 		    } else if (seldata.start == 0 ||
   2916 			       seldata.end == 0) {
   2917 			/* ":[0..N]" or ":[N..0]" */
   2918 			free(estr);
   2919 			goto bad_modifier;
   2920 		    }
   2921 		    /*
   2922 		     * Normal case: select the words
   2923 		     * described by seldata.
   2924 		     */
   2925 		    newStr = VarSelectWords(ctxt, &parsestate,
   2926 					    nstr, &seldata);
   2927 
   2928 		    termc = *cp;
   2929 		    free(estr);
   2930 		    break;
   2931 		}
   2932 
   2933 	    }
   2934 	case 'g':
   2935 	    cp = tstr + 1;	/* make sure it is set */
   2936 	    if (STRMOD_MATCH(tstr, "gmtime", 6)) {
   2937 		newStr = VarStrftime(nstr, 1);
   2938 		cp = tstr + 6;
   2939 		termc = *cp;
   2940 	    } else {
   2941 		goto default_case;
   2942 	    }
   2943 	    break;
   2944 	case 'h':
   2945 	    cp = tstr + 1;	/* make sure it is set */
   2946 	    if (STRMOD_MATCH(tstr, "hash", 4)) {
   2947 		newStr = VarHash(nstr);
   2948 		cp = tstr + 4;
   2949 		termc = *cp;
   2950 	    } else {
   2951 		goto default_case;
   2952 	    }
   2953 	    break;
   2954 	case 'l':
   2955 	    cp = tstr + 1;	/* make sure it is set */
   2956 	    if (STRMOD_MATCH(tstr, "localtime", 9)) {
   2957 		newStr = VarStrftime(nstr, 0);
   2958 		cp = tstr + 9;
   2959 		termc = *cp;
   2960 	    } else {
   2961 		goto default_case;
   2962 	    }
   2963 	    break;
   2964 	case 't':
   2965 	    {
   2966 		cp = tstr + 1;	/* make sure it is set */
   2967 		if (tstr[1] != endc && tstr[1] != ':') {
   2968 		    if (tstr[1] == 's') {
   2969 			/*
   2970 			 * Use the char (if any) at tstr[2]
   2971 			 * as the word separator.
   2972 			 */
   2973 			VarPattern pattern;
   2974 
   2975 			if (tstr[2] != endc &&
   2976 			    (tstr[3] == endc || tstr[3] == ':')) {
   2977 			    /* ":ts<unrecognised><endc>" or
   2978 			     * ":ts<unrecognised>:" */
   2979 			    parsestate.varSpace = tstr[2];
   2980 			    cp = tstr + 3;
   2981 			} else if (tstr[2] == endc || tstr[2] == ':') {
   2982 			    /* ":ts<endc>" or ":ts:" */
   2983 			    parsestate.varSpace = 0; /* no separator */
   2984 			    cp = tstr + 2;
   2985 			} else if (tstr[2] == '\\') {
   2986 			    switch (tstr[3]) {
   2987 			    case 'n':
   2988 				parsestate.varSpace = '\n';
   2989 				cp = tstr + 4;
   2990 				break;
   2991 			    case 't':
   2992 				parsestate.varSpace = '\t';
   2993 				cp = tstr + 4;
   2994 				break;
   2995 			    default:
   2996 				if (isdigit((unsigned char)tstr[3])) {
   2997 				    char *ep;
   2998 
   2999 				    parsestate.varSpace =
   3000 					strtoul(&tstr[3], &ep, 0);
   3001 				    if (*ep != ':' && *ep != endc)
   3002 					goto bad_modifier;
   3003 				    cp = ep;
   3004 				} else {
   3005 				    /*
   3006 				     * ":ts<backslash><unrecognised>".
   3007 				     */
   3008 				    goto bad_modifier;
   3009 				}
   3010 				break;
   3011 			    }
   3012 			} else {
   3013 			    /*
   3014 			     * Found ":ts<unrecognised><unrecognised>".
   3015 			     */
   3016 			    goto bad_modifier;
   3017 			}
   3018 
   3019 			termc = *cp;
   3020 
   3021 			/*
   3022 			 * We cannot be certain that VarModify
   3023 			 * will be used - even if there is a
   3024 			 * subsequent modifier, so do a no-op
   3025 			 * VarSubstitute now to for str to be
   3026 			 * re-expanded without the spaces.
   3027 			 */
   3028 			pattern.flags = VAR_SUB_ONE;
   3029 			pattern.lhs = pattern.rhs = "\032";
   3030 			pattern.leftLen = pattern.rightLen = 1;
   3031 
   3032 			newStr = VarModify(ctxt, &parsestate, nstr,
   3033 					   VarSubstitute,
   3034 					   &pattern);
   3035 		    } else if (tstr[2] == endc || tstr[2] == ':') {
   3036 			/*
   3037 			 * Check for two-character options:
   3038 			 * ":tu", ":tl"
   3039 			 */
   3040 			if (tstr[1] == 'A') { /* absolute path */
   3041 			    newStr = VarModify(ctxt, &parsestate, nstr,
   3042 					       VarRealpath, NULL);
   3043 			    cp = tstr + 2;
   3044 			    termc = *cp;
   3045 			} else if (tstr[1] == 'u' || tstr[1] == 'l') {
   3046 			    newStr = VarChangeCase(nstr, (tstr[1] == 'u'));
   3047 			    cp = tstr + 2;
   3048 			    termc = *cp;
   3049 			} else if (tstr[1] == 'W' || tstr[1] == 'w') {
   3050 			    parsestate.oneBigWord = (tstr[1] == 'W');
   3051 			    newStr = nstr;
   3052 			    cp = tstr + 2;
   3053 			    termc = *cp;
   3054 			} else {
   3055 			    /* Found ":t<unrecognised>:" or
   3056 			     * ":t<unrecognised><endc>". */
   3057 			    goto bad_modifier;
   3058 			}
   3059 		    } else {
   3060 			/*
   3061 			 * Found ":t<unrecognised><unrecognised>".
   3062 			 */
   3063 			goto bad_modifier;
   3064 		    }
   3065 		} else {
   3066 		    /*
   3067 		     * Found ":t<endc>" or ":t:".
   3068 		     */
   3069 		    goto bad_modifier;
   3070 		}
   3071 		break;
   3072 	    }
   3073 	case 'N':
   3074 	case 'M':
   3075 	    {
   3076 		char    *pattern;
   3077 		const char *endpat; /* points just after end of pattern */
   3078 		char    *cp2;
   3079 		Boolean copy;	/* pattern should be, or has been, copied */
   3080 		Boolean needSubst;
   3081 		int nest;
   3082 
   3083 		copy = FALSE;
   3084 		needSubst = FALSE;
   3085 		nest = 1;
   3086 		/*
   3087 		 * In the loop below, ignore ':' unless we are at
   3088 		 * (or back to) the original brace level.
   3089 		 * XXX This will likely not work right if $() and ${}
   3090 		 * are intermixed.
   3091 		 */
   3092 		for (cp = tstr + 1;
   3093 		     *cp != '\0' && !(*cp == ':' && nest == 1);
   3094 		     cp++)
   3095 		    {
   3096 			if (*cp == '\\' &&
   3097 			    (cp[1] == ':' ||
   3098 			     cp[1] == endc || cp[1] == startc)) {
   3099 			    if (!needSubst) {
   3100 				copy = TRUE;
   3101 			    }
   3102 			    cp++;
   3103 			    continue;
   3104 			}
   3105 			if (*cp == '$') {
   3106 			    needSubst = TRUE;
   3107 			}
   3108 			if (*cp == '(' || *cp == '{')
   3109 			    ++nest;
   3110 			if (*cp == ')' || *cp == '}') {
   3111 			    --nest;
   3112 			    if (nest == 0)
   3113 				break;
   3114 			}
   3115 		    }
   3116 		termc = *cp;
   3117 		endpat = cp;
   3118 		if (copy) {
   3119 		    /*
   3120 		     * Need to compress the \:'s out of the pattern, so
   3121 		     * allocate enough room to hold the uncompressed
   3122 		     * pattern (note that cp started at tstr+1, so
   3123 		     * cp - tstr takes the null byte into account) and
   3124 		     * compress the pattern into the space.
   3125 		     */
   3126 		    pattern = bmake_malloc(cp - tstr);
   3127 		    for (cp2 = pattern, cp = tstr + 1;
   3128 			 cp < endpat;
   3129 			 cp++, cp2++)
   3130 			{
   3131 			    if ((*cp == '\\') && (cp+1 < endpat) &&
   3132 				(cp[1] == ':' || cp[1] == endc)) {
   3133 				cp++;
   3134 			    }
   3135 			    *cp2 = *cp;
   3136 			}
   3137 		    *cp2 = '\0';
   3138 		    endpat = cp2;
   3139 		} else {
   3140 		    /*
   3141 		     * Either Var_Subst or VarModify will need a
   3142 		     * nul-terminated string soon, so construct one now.
   3143 		     */
   3144 		    pattern = bmake_strndup(tstr+1, endpat - (tstr + 1));
   3145 		}
   3146 		if (needSubst) {
   3147 		    /*
   3148 		     * pattern contains embedded '$', so use Var_Subst to
   3149 		     * expand it.
   3150 		     */
   3151 		    cp2 = pattern;
   3152 		    pattern = Var_Subst(NULL, cp2, ctxt, errnum);
   3153 		    free(cp2);
   3154 		}
   3155 		if (DEBUG(VAR))
   3156 		    fprintf(debug_file, "Pattern for [%s] is [%s]\n", nstr,
   3157 			pattern);
   3158 		if (*tstr == 'M') {
   3159 		    newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
   3160 				       pattern);
   3161 		} else {
   3162 		    newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
   3163 				       pattern);
   3164 		}
   3165 		free(pattern);
   3166 		break;
   3167 	    }
   3168 	case 'S':
   3169 	    {
   3170 		VarPattern 	    pattern;
   3171 		Var_Parse_State tmpparsestate;
   3172 
   3173 		pattern.flags = 0;
   3174 		tmpparsestate = parsestate;
   3175 		delim = tstr[1];
   3176 		tstr += 2;
   3177 
   3178 		/*
   3179 		 * If pattern begins with '^', it is anchored to the
   3180 		 * start of the word -- skip over it and flag pattern.
   3181 		 */
   3182 		if (*tstr == '^') {
   3183 		    pattern.flags |= VAR_MATCH_START;
   3184 		    tstr += 1;
   3185 		}
   3186 
   3187 		cp = tstr;
   3188 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
   3189 						 &cp, delim,
   3190 						 &pattern.flags,
   3191 						 &pattern.leftLen,
   3192 						 NULL)) == NULL)
   3193 		    goto cleanup;
   3194 
   3195 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   3196 						 &cp, delim, NULL,
   3197 						 &pattern.rightLen,
   3198 						 &pattern)) == NULL)
   3199 		    goto cleanup;
   3200 
   3201 		/*
   3202 		 * Check for global substitution. If 'g' after the final
   3203 		 * delimiter, substitution is global and is marked that
   3204 		 * way.
   3205 		 */
   3206 		for (;; cp++) {
   3207 		    switch (*cp) {
   3208 		    case 'g':
   3209 			pattern.flags |= VAR_SUB_GLOBAL;
   3210 			continue;
   3211 		    case '1':
   3212 			pattern.flags |= VAR_SUB_ONE;
   3213 			continue;
   3214 		    case 'W':
   3215 			tmpparsestate.oneBigWord = TRUE;
   3216 			continue;
   3217 		    }
   3218 		    break;
   3219 		}
   3220 
   3221 		termc = *cp;
   3222 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
   3223 				   VarSubstitute,
   3224 				   &pattern);
   3225 
   3226 		/*
   3227 		 * Free the two strings.
   3228 		 */
   3229 		free(UNCONST(pattern.lhs));
   3230 		free(UNCONST(pattern.rhs));
   3231 		delim = '\0';
   3232 		break;
   3233 	    }
   3234 	case '?':
   3235 	    {
   3236 		VarPattern 	pattern;
   3237 		Boolean	value;
   3238 
   3239 		/* find ':', and then substitute accordingly */
   3240 
   3241 		pattern.flags = 0;
   3242 
   3243 		cp = ++tstr;
   3244 		delim = ':';
   3245 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
   3246 						 &cp, delim, NULL,
   3247 						 &pattern.leftLen,
   3248 						 NULL)) == NULL)
   3249 		    goto cleanup;
   3250 
   3251 		/* BROPEN or PROPEN */
   3252 		delim = endc;
   3253 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   3254 						 &cp, delim, NULL,
   3255 						 &pattern.rightLen,
   3256 						 NULL)) == NULL)
   3257 		    goto cleanup;
   3258 
   3259 		termc = *--cp;
   3260 		delim = '\0';
   3261 		if (Cond_EvalExpression(NULL, v->name, &value, 0)
   3262 		    == COND_INVALID) {
   3263 		    Error("Bad conditional expression `%s' in %s?%s:%s",
   3264 			  v->name, v->name, pattern.lhs, pattern.rhs);
   3265 		    goto cleanup;
   3266 		}
   3267 
   3268 		if (value) {
   3269 		    newStr = UNCONST(pattern.lhs);
   3270 		    free(UNCONST(pattern.rhs));
   3271 		} else {
   3272 		    newStr = UNCONST(pattern.rhs);
   3273 		    free(UNCONST(pattern.lhs));
   3274 		}
   3275 		if (v->flags & VAR_JUNK) {
   3276 		    v->flags |= VAR_KEEP;
   3277 		}
   3278 		break;
   3279 	    }
   3280 #ifndef NO_REGEX
   3281 	case 'C':
   3282 	    {
   3283 		VarREPattern    pattern;
   3284 		char           *re;
   3285 		int             error;
   3286 		Var_Parse_State tmpparsestate;
   3287 
   3288 		pattern.flags = 0;
   3289 		tmpparsestate = parsestate;
   3290 		delim = tstr[1];
   3291 		tstr += 2;
   3292 
   3293 		cp = tstr;
   3294 
   3295 		if ((re = VarGetPattern(ctxt, &parsestate, errnum, &cp, delim,
   3296 					NULL, NULL, NULL)) == NULL)
   3297 		    goto cleanup;
   3298 
   3299 		if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
   3300 						     errnum, &cp, delim, NULL,
   3301 						     NULL, NULL)) == NULL){
   3302 		    free(re);
   3303 		    goto cleanup;
   3304 		}
   3305 
   3306 		for (;; cp++) {
   3307 		    switch (*cp) {
   3308 		    case 'g':
   3309 			pattern.flags |= VAR_SUB_GLOBAL;
   3310 			continue;
   3311 		    case '1':
   3312 			pattern.flags |= VAR_SUB_ONE;
   3313 			continue;
   3314 		    case 'W':
   3315 			tmpparsestate.oneBigWord = TRUE;
   3316 			continue;
   3317 		    }
   3318 		    break;
   3319 		}
   3320 
   3321 		termc = *cp;
   3322 
   3323 		error = regcomp(&pattern.re, re, REG_EXTENDED);
   3324 		free(re);
   3325 		if (error)  {
   3326 		    *lengthPtr = cp - start + 1;
   3327 		    VarREError(error, &pattern.re, "RE substitution error");
   3328 		    free(pattern.replace);
   3329 		    goto cleanup;
   3330 		}
   3331 
   3332 		pattern.nsub = pattern.re.re_nsub + 1;
   3333 		if (pattern.nsub < 1)
   3334 		    pattern.nsub = 1;
   3335 		if (pattern.nsub > 10)
   3336 		    pattern.nsub = 10;
   3337 		pattern.matches = bmake_malloc(pattern.nsub *
   3338 					  sizeof(regmatch_t));
   3339 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
   3340 				   VarRESubstitute,
   3341 				   &pattern);
   3342 		regfree(&pattern.re);
   3343 		free(pattern.replace);
   3344 		free(pattern.matches);
   3345 		delim = '\0';
   3346 		break;
   3347 	    }
   3348 #endif
   3349 	case 'Q':
   3350 	    if (tstr[1] == endc || tstr[1] == ':') {
   3351 		newStr = VarQuote(nstr);
   3352 		cp = tstr + 1;
   3353 		termc = *cp;
   3354 		break;
   3355 	    }
   3356 	    goto default_case;
   3357 	case 'T':
   3358 	    if (tstr[1] == endc || tstr[1] == ':') {
   3359 		newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
   3360 				   NULL);
   3361 		cp = tstr + 1;
   3362 		termc = *cp;
   3363 		break;
   3364 	    }
   3365 	    goto default_case;
   3366 	case 'H':
   3367 	    if (tstr[1] == endc || tstr[1] == ':') {
   3368 		newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
   3369 				   NULL);
   3370 		cp = tstr + 1;
   3371 		termc = *cp;
   3372 		break;
   3373 	    }
   3374 	    goto default_case;
   3375 	case 'E':
   3376 	    if (tstr[1] == endc || tstr[1] == ':') {
   3377 		newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
   3378 				   NULL);
   3379 		cp = tstr + 1;
   3380 		termc = *cp;
   3381 		break;
   3382 	    }
   3383 	    goto default_case;
   3384 	case 'R':
   3385 	    if (tstr[1] == endc || tstr[1] == ':') {
   3386 		newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
   3387 				   NULL);
   3388 		cp = tstr + 1;
   3389 		termc = *cp;
   3390 		break;
   3391 	    }
   3392 	    goto default_case;
   3393 	case 'O':
   3394 	    {
   3395 		char otype;
   3396 
   3397 		cp = tstr + 1;	/* skip to the rest in any case */
   3398 		if (tstr[1] == endc || tstr[1] == ':') {
   3399 		    otype = 's';
   3400 		    termc = *cp;
   3401 		} else if ( (tstr[1] == 'x') &&
   3402 			    (tstr[2] == endc || tstr[2] == ':') ) {
   3403 		    otype = tstr[1];
   3404 		    cp = tstr + 2;
   3405 		    termc = *cp;
   3406 		} else {
   3407 		    goto bad_modifier;
   3408 		}
   3409 		newStr = VarOrder(nstr, otype);
   3410 		break;
   3411 	    }
   3412 	case 'u':
   3413 	    if (tstr[1] == endc || tstr[1] == ':') {
   3414 		newStr = VarUniq(nstr);
   3415 		cp = tstr + 1;
   3416 		termc = *cp;
   3417 		break;
   3418 	    }
   3419 	    goto default_case;
   3420 #ifdef SUNSHCMD
   3421 	case 's':
   3422 	    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
   3423 		const char *emsg;
   3424 		newStr = Cmd_Exec(nstr, &emsg);
   3425 		if (emsg)
   3426 		    Error(emsg, nstr);
   3427 		cp = tstr + 2;
   3428 		termc = *cp;
   3429 		break;
   3430 	    }
   3431 	    goto default_case;
   3432 #endif
   3433 	default:
   3434 	default_case:
   3435 	{
   3436 #ifdef SYSVVARSUB
   3437 	    /*
   3438 	     * This can either be a bogus modifier or a System-V
   3439 	     * substitution command.
   3440 	     */
   3441 	    VarPattern      pattern;
   3442 	    Boolean         eqFound;
   3443 
   3444 	    pattern.flags = 0;
   3445 	    eqFound = FALSE;
   3446 	    /*
   3447 	     * First we make a pass through the string trying
   3448 	     * to verify it is a SYSV-make-style translation:
   3449 	     * it must be: <string1>=<string2>)
   3450 	     */
   3451 	    cp = tstr;
   3452 	    cnt = 1;
   3453 	    while (*cp != '\0' && cnt) {
   3454 		if (*cp == '=') {
   3455 		    eqFound = TRUE;
   3456 		    /* continue looking for endc */
   3457 		}
   3458 		else if (*cp == endc)
   3459 		    cnt--;
   3460 		else if (*cp == startc)
   3461 		    cnt++;
   3462 		if (cnt)
   3463 		    cp++;
   3464 	    }
   3465 	    if (*cp == endc && eqFound) {
   3466 
   3467 		/*
   3468 		 * Now we break this sucker into the lhs and
   3469 		 * rhs. We must null terminate them of course.
   3470 		 */
   3471 		delim='=';
   3472 		cp = tstr;
   3473 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
   3474 						 errnum, &cp, delim, &pattern.flags,
   3475 						 &pattern.leftLen, NULL)) == NULL)
   3476 		    goto cleanup;
   3477 		delim = endc;
   3478 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
   3479 						 errnum, &cp, delim, NULL, &pattern.rightLen,
   3480 						 &pattern)) == NULL)
   3481 		    goto cleanup;
   3482 
   3483 		/*
   3484 		 * SYSV modifications happen through the whole
   3485 		 * string. Note the pattern is anchored at the end.
   3486 		 */
   3487 		termc = *--cp;
   3488 		delim = '\0';
   3489 		if (pattern.leftLen == 0 && *nstr == '\0') {
   3490 		    newStr = nstr;	/* special case */
   3491 		} else {
   3492 		    newStr = VarModify(ctxt, &parsestate, nstr,
   3493 				       VarSYSVMatch,
   3494 				       &pattern);
   3495 		}
   3496 		free(UNCONST(pattern.lhs));
   3497 		free(UNCONST(pattern.rhs));
   3498 	    } else
   3499 #endif
   3500 		{
   3501 		    Error("Unknown modifier '%c'", *tstr);
   3502 		    for (cp = tstr+1;
   3503 			 *cp != ':' && *cp != endc && *cp != '\0';
   3504 			 cp++)
   3505 			continue;
   3506 		    termc = *cp;
   3507 		    newStr = var_Error;
   3508 		}
   3509 	    }
   3510 	}
   3511 	if (DEBUG(VAR)) {
   3512 	    fprintf(debug_file, "Result of :%c is \"%s\"\n", modifier, newStr);
   3513 	}
   3514 
   3515 	if (newStr != nstr) {
   3516 	    if (*freePtr) {
   3517 		free(nstr);
   3518 		*freePtr = NULL;
   3519 	    }
   3520 	    nstr = newStr;
   3521 	    if (nstr != var_Error && nstr != varNoError) {
   3522 		*freePtr = nstr;
   3523 	    }
   3524 	}
   3525 	if (termc == '\0' && endc != '\0') {
   3526 	    Error("Unclosed variable specification (expecting '%c') for \"%s\" (value \"%s\") modifier %c", endc, v->name, nstr, modifier);
   3527 	} else if (termc == ':') {
   3528 	    cp++;
   3529 	}
   3530 	tstr = cp;
   3531     }
   3532  out:
   3533     *lengthPtr = tstr - start;
   3534     return (nstr);
   3535 
   3536  bad_modifier:
   3537     /* "{(" */
   3538     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
   3539 	  v->name);
   3540 
   3541  cleanup:
   3542     *lengthPtr = cp - start;
   3543     if (delim != '\0')
   3544 	Error("Unclosed substitution for %s (%c missing)",
   3545 	      v->name, delim);
   3546     if (*freePtr) {
   3547 	free(*freePtr);
   3548 	*freePtr = NULL;
   3549     }
   3550     return (var_Error);
   3551 }
   3552 
   3553 /*-
   3554  *-----------------------------------------------------------------------
   3555  * Var_Parse --
   3556  *	Given the start of a variable invocation, extract the variable
   3557  *	name and find its value, then modify it according to the
   3558  *	specification.
   3559  *
   3560  * Input:
   3561  *	str		The string to parse
   3562  *	ctxt		The context for the variable
   3563  *	errnum		TRUE if undefined variables are an error
   3564  *	lengthPtr	OUT: The length of the specification
   3565  *	freePtr		OUT: Non-NULL if caller should free *freePtr
   3566  *
   3567  * Results:
   3568  *	The (possibly-modified) value of the variable or var_Error if the
   3569  *	specification is invalid. The length of the specification is
   3570  *	placed in *lengthPtr (for invalid specifications, this is just
   3571  *	2...?).
   3572  *	If *freePtr is non-NULL then it's a pointer that the caller
   3573  *	should pass to free() to free memory used by the result.
   3574  *
   3575  * Side Effects:
   3576  *	None.
   3577  *
   3578  *-----------------------------------------------------------------------
   3579  */
   3580 /* coverity[+alloc : arg-*4] */
   3581 char *
   3582 Var_Parse(const char *str, GNode *ctxt, Boolean errnum, int *lengthPtr,
   3583 	  void **freePtr)
   3584 {
   3585     const char	   *tstr;    	/* Pointer into str */
   3586     Var		   *v;		/* Variable in invocation */
   3587     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
   3588     char	    endc;    	/* Ending character when variable in parens
   3589 				 * or braces */
   3590     char	    startc;	/* Starting character when variable in parens
   3591 				 * or braces */
   3592     int		    vlen;	/* Length of variable name */
   3593     const char 	   *start;	/* Points to original start of str */
   3594     char	   *nstr;	/* New string, used during expansion */
   3595     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
   3596 				 * expanding it in a non-local context. This
   3597 				 * is done to support dynamic sources. The
   3598 				 * result is just the invocation, unaltered */
   3599     Var_Parse_State parsestate; /* Flags passed to helper functions */
   3600     char	  name[2];
   3601 
   3602     *freePtr = NULL;
   3603     dynamic = FALSE;
   3604     start = str;
   3605     parsestate.oneBigWord = FALSE;
   3606     parsestate.varSpace = ' ';	/* word separator */
   3607 
   3608     startc = str[1];
   3609     if (startc != PROPEN && startc != BROPEN) {
   3610 	/*
   3611 	 * If it's not bounded by braces of some sort, life is much simpler.
   3612 	 * We just need to check for the first character and return the
   3613 	 * value if it exists.
   3614 	 */
   3615 
   3616 	/* Error out some really stupid names */
   3617 	if (startc == '\0' || strchr(")}:$", startc)) {
   3618 	    *lengthPtr = 1;
   3619 	    return var_Error;
   3620 	}
   3621 	name[0] = startc;
   3622 	name[1] = '\0';
   3623 
   3624 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   3625 	if (v == NULL) {
   3626 	    *lengthPtr = 2;
   3627 
   3628 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
   3629 		/*
   3630 		 * If substituting a local variable in a non-local context,
   3631 		 * assume it's for dynamic source stuff. We have to handle
   3632 		 * this specially and return the longhand for the variable
   3633 		 * with the dollar sign escaped so it makes it back to the
   3634 		 * caller. Only four of the local variables are treated
   3635 		 * specially as they are the only four that will be set
   3636 		 * when dynamic sources are expanded.
   3637 		 */
   3638 		switch (str[1]) {
   3639 		    case '@':
   3640 			return UNCONST("$(.TARGET)");
   3641 		    case '%':
   3642 			return UNCONST("$(.ARCHIVE)");
   3643 		    case '*':
   3644 			return UNCONST("$(.PREFIX)");
   3645 		    case '!':
   3646 			return UNCONST("$(.MEMBER)");
   3647 		}
   3648 	    }
   3649 	    /*
   3650 	     * Error
   3651 	     */
   3652 	    return (errnum ? var_Error : varNoError);
   3653 	} else {
   3654 	    haveModifier = FALSE;
   3655 	    tstr = &str[1];
   3656 	    endc = str[1];
   3657 	}
   3658     } else {
   3659 	Buffer buf;	/* Holds the variable name */
   3660 
   3661 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
   3662 	Buf_Init(&buf, 0);
   3663 
   3664 	/*
   3665 	 * Skip to the end character or a colon, whichever comes first.
   3666 	 */
   3667 	for (tstr = str + 2;
   3668 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
   3669 	     tstr++)
   3670 	{
   3671 	    /*
   3672 	     * A variable inside a variable, expand
   3673 	     */
   3674 	    if (*tstr == '$') {
   3675 		int rlen;
   3676 		void *freeIt;
   3677 		char *rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
   3678 		if (rval != NULL) {
   3679 		    Buf_AddBytes(&buf, strlen(rval), rval);
   3680 		}
   3681 		if (freeIt)
   3682 		    free(freeIt);
   3683 		tstr += rlen - 1;
   3684 	    }
   3685 	    else
   3686 		Buf_AddByte(&buf, *tstr);
   3687 	}
   3688 	if (*tstr == ':') {
   3689 	    haveModifier = TRUE;
   3690 	} else if (*tstr != '\0') {
   3691 	    haveModifier = FALSE;
   3692 	} else {
   3693 	    /*
   3694 	     * If we never did find the end character, return NULL
   3695 	     * right now, setting the length to be the distance to
   3696 	     * the end of the string, since that's what make does.
   3697 	     */
   3698 	    *lengthPtr = tstr - str;
   3699 	    Buf_Destroy(&buf, TRUE);
   3700 	    return (var_Error);
   3701 	}
   3702 	str = Buf_GetAll(&buf, &vlen);
   3703 
   3704 	/*
   3705 	 * At this point, str points into newly allocated memory from
   3706 	 * buf, containing only the name of the variable.
   3707 	 *
   3708 	 * start and tstr point into the const string that was pointed
   3709 	 * to by the original value of the str parameter.  start points
   3710 	 * to the '$' at the beginning of the string, while tstr points
   3711 	 * to the char just after the end of the variable name -- this
   3712 	 * will be '\0', ':', PRCLOSE, or BRCLOSE.
   3713 	 */
   3714 
   3715 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   3716 	/*
   3717 	 * Check also for bogus D and F forms of local variables since we're
   3718 	 * in a local context and the name is the right length.
   3719 	 */
   3720 	if ((v == NULL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
   3721 		(vlen == 2) && (str[1] == 'F' || str[1] == 'D') &&
   3722 		strchr("@%*!<>", str[0]) != NULL) {
   3723 	    /*
   3724 	     * Well, it's local -- go look for it.
   3725 	     */
   3726 	    name[0] = *str;
   3727 	    name[1] = '\0';
   3728 	    v = VarFind(name, ctxt, 0);
   3729 
   3730 	    if (v != NULL) {
   3731 		/*
   3732 		 * No need for nested expansion or anything, as we're
   3733 		 * the only one who sets these things and we sure don't
   3734 		 * but nested invocations in them...
   3735 		 */
   3736 		nstr = Buf_GetAll(&v->val, NULL);
   3737 
   3738 		if (str[1] == 'D') {
   3739 		    nstr = VarModify(ctxt, &parsestate, nstr, VarHead,
   3740 				    NULL);
   3741 		} else {
   3742 		    nstr = VarModify(ctxt, &parsestate, nstr, VarTail,
   3743 				    NULL);
   3744 		}
   3745 		/*
   3746 		 * Resulting string is dynamically allocated, so
   3747 		 * tell caller to free it.
   3748 		 */
   3749 		*freePtr = nstr;
   3750 		*lengthPtr = tstr-start+1;
   3751 		Buf_Destroy(&buf, TRUE);
   3752 		VarFreeEnv(v, TRUE);
   3753 		return nstr;
   3754 	    }
   3755 	}
   3756 
   3757 	if (v == NULL) {
   3758 	    if (((vlen == 1) ||
   3759 		 (((vlen == 2) && (str[1] == 'F' || str[1] == 'D')))) &&
   3760 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
   3761 	    {
   3762 		/*
   3763 		 * If substituting a local variable in a non-local context,
   3764 		 * assume it's for dynamic source stuff. We have to handle
   3765 		 * this specially and return the longhand for the variable
   3766 		 * with the dollar sign escaped so it makes it back to the
   3767 		 * caller. Only four of the local variables are treated
   3768 		 * specially as they are the only four that will be set
   3769 		 * when dynamic sources are expanded.
   3770 		 */
   3771 		switch (*str) {
   3772 		    case '@':
   3773 		    case '%':
   3774 		    case '*':
   3775 		    case '!':
   3776 			dynamic = TRUE;
   3777 			break;
   3778 		}
   3779 	    } else if ((vlen > 2) && (*str == '.') &&
   3780 		       isupper((unsigned char) str[1]) &&
   3781 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
   3782 	    {
   3783 		int	len;
   3784 
   3785 		len = vlen - 1;
   3786 		if ((strncmp(str, ".TARGET", len) == 0) ||
   3787 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
   3788 		    (strncmp(str, ".PREFIX", len) == 0) ||
   3789 		    (strncmp(str, ".MEMBER", len) == 0))
   3790 		{
   3791 		    dynamic = TRUE;
   3792 		}
   3793 	    }
   3794 
   3795 	    if (!haveModifier) {
   3796 		/*
   3797 		 * No modifiers -- have specification length so we can return
   3798 		 * now.
   3799 		 */
   3800 		*lengthPtr = tstr - start + 1;
   3801 		if (dynamic) {
   3802 		    char *pstr = bmake_strndup(start, *lengthPtr);
   3803 		    *freePtr = pstr;
   3804 		    Buf_Destroy(&buf, TRUE);
   3805 		    return(pstr);
   3806 		} else {
   3807 		    Buf_Destroy(&buf, TRUE);
   3808 		    return (errnum ? var_Error : varNoError);
   3809 		}
   3810 	    } else {
   3811 		/*
   3812 		 * Still need to get to the end of the variable specification,
   3813 		 * so kludge up a Var structure for the modifications
   3814 		 */
   3815 		v = bmake_malloc(sizeof(Var));
   3816 		v->name = UNCONST(str);
   3817 		Buf_Init(&v->val, 1);
   3818 		v->flags = VAR_JUNK;
   3819 		Buf_Destroy(&buf, FALSE);
   3820 	    }
   3821 	} else
   3822 	    Buf_Destroy(&buf, TRUE);
   3823     }
   3824 
   3825     if (v->flags & VAR_IN_USE) {
   3826 	Fatal("Variable %s is recursive.", v->name);
   3827 	/*NOTREACHED*/
   3828     } else {
   3829 	v->flags |= VAR_IN_USE;
   3830     }
   3831     /*
   3832      * Before doing any modification, we have to make sure the value
   3833      * has been fully expanded. If it looks like recursion might be
   3834      * necessary (there's a dollar sign somewhere in the variable's value)
   3835      * we just call Var_Subst to do any other substitutions that are
   3836      * necessary. Note that the value returned by Var_Subst will have
   3837      * been dynamically-allocated, so it will need freeing when we
   3838      * return.
   3839      */
   3840     nstr = Buf_GetAll(&v->val, NULL);
   3841     if (strchr(nstr, '$') != NULL) {
   3842 	nstr = Var_Subst(NULL, nstr, ctxt, errnum);
   3843 	*freePtr = nstr;
   3844     }
   3845 
   3846     v->flags &= ~VAR_IN_USE;
   3847 
   3848     if ((nstr != NULL) && haveModifier) {
   3849 	int used;
   3850 	/*
   3851 	 * Skip initial colon.
   3852 	 */
   3853 	tstr++;
   3854 
   3855 	nstr = ApplyModifiers(nstr, tstr, startc, endc,
   3856 			      v, ctxt, errnum, &used, freePtr);
   3857 	tstr += used;
   3858     }
   3859     if (*tstr) {
   3860 	*lengthPtr = tstr - start + 1;
   3861     } else {
   3862 	*lengthPtr = tstr - start;
   3863     }
   3864 
   3865     if (v->flags & VAR_FROM_ENV) {
   3866 	Boolean	  destroy = FALSE;
   3867 
   3868 	if (nstr != Buf_GetAll(&v->val, NULL)) {
   3869 	    destroy = TRUE;
   3870 	} else {
   3871 	    /*
   3872 	     * Returning the value unmodified, so tell the caller to free
   3873 	     * the thing.
   3874 	     */
   3875 	    *freePtr = nstr;
   3876 	}
   3877 	VarFreeEnv(v, destroy);
   3878     } else if (v->flags & VAR_JUNK) {
   3879 	/*
   3880 	 * Perform any free'ing needed and set *freePtr to NULL so the caller
   3881 	 * doesn't try to free a static pointer.
   3882 	 * If VAR_KEEP is also set then we want to keep str as is.
   3883 	 */
   3884 	if (!(v->flags & VAR_KEEP)) {
   3885 	    if (*freePtr) {
   3886 		free(nstr);
   3887 		*freePtr = NULL;
   3888 	    }
   3889 	    if (dynamic) {
   3890 		nstr = bmake_strndup(start, *lengthPtr);
   3891 		*freePtr = nstr;
   3892 	    } else {
   3893 		nstr = errnum ? var_Error : varNoError;
   3894 	    }
   3895 	}
   3896 	if (nstr != Buf_GetAll(&v->val, NULL))
   3897 	    Buf_Destroy(&v->val, TRUE);
   3898 	free(v->name);
   3899 	free(v);
   3900     }
   3901     return (nstr);
   3902 }
   3903 
   3904 /*-
   3905  *-----------------------------------------------------------------------
   3906  * Var_Subst  --
   3907  *	Substitute for all variables in the given string in the given context
   3908  *	If undefErr is TRUE, Parse_Error will be called when an undefined
   3909  *	variable is encountered.
   3910  *
   3911  * Input:
   3912  *	var		Named variable || NULL for all
   3913  *	str		the string which to substitute
   3914  *	ctxt		the context wherein to find variables
   3915  *	undefErr	TRUE if undefineds are an error
   3916  *
   3917  * Results:
   3918  *	The resulting string.
   3919  *
   3920  * Side Effects:
   3921  *	None. The old string must be freed by the caller
   3922  *-----------------------------------------------------------------------
   3923  */
   3924 char *
   3925 Var_Subst(const char *var, const char *str, GNode *ctxt, Boolean undefErr)
   3926 {
   3927     Buffer  	  buf;		    /* Buffer for forming things */
   3928     char    	  *val;		    /* Value to substitute for a variable */
   3929     int		  length;   	    /* Length of the variable invocation */
   3930     Boolean	  trailingBslash;   /* variable ends in \ */
   3931     void 	  *freeIt = NULL;    /* Set if it should be freed */
   3932     static Boolean errorReported;   /* Set true if an error has already
   3933 				     * been reported to prevent a plethora
   3934 				     * of messages when recursing */
   3935 
   3936     Buf_Init(&buf, 0);
   3937     errorReported = FALSE;
   3938     trailingBslash = FALSE;
   3939 
   3940     while (*str) {
   3941 	if (*str == '\n' && trailingBslash)
   3942 	    Buf_AddByte(&buf, ' ');
   3943 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
   3944 	    /*
   3945 	     * A dollar sign may be escaped either with another dollar sign.
   3946 	     * In such a case, we skip over the escape character and store the
   3947 	     * dollar sign into the buffer directly.
   3948 	     */
   3949 	    str++;
   3950 	    Buf_AddByte(&buf, *str);
   3951 	    str++;
   3952 	} else if (*str != '$') {
   3953 	    /*
   3954 	     * Skip as many characters as possible -- either to the end of
   3955 	     * the string or to the next dollar sign (variable invocation).
   3956 	     */
   3957 	    const char  *cp;
   3958 
   3959 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
   3960 		continue;
   3961 	    Buf_AddBytes(&buf, str - cp, cp);
   3962 	} else {
   3963 	    if (var != NULL) {
   3964 		int expand;
   3965 		for (;;) {
   3966 		    if (str[1] == '\0') {
   3967 			/* A trailing $ is kind of a special case */
   3968 			Buf_AddByte(&buf, str[0]);
   3969 			str++;
   3970 			expand = FALSE;
   3971 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
   3972 			if (str[1] != *var || strlen(var) > 1) {
   3973 			    Buf_AddBytes(&buf, 2, str);
   3974 			    str += 2;
   3975 			    expand = FALSE;
   3976 			}
   3977 			else
   3978 			    expand = TRUE;
   3979 			break;
   3980 		    }
   3981 		    else {
   3982 			const char *p;
   3983 
   3984 			/*
   3985 			 * Scan up to the end of the variable name.
   3986 			 */
   3987 			for (p = &str[2]; *p &&
   3988 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
   3989 			    if (*p == '$')
   3990 				break;
   3991 			/*
   3992 			 * A variable inside the variable. We cannot expand
   3993 			 * the external variable yet, so we try again with
   3994 			 * the nested one
   3995 			 */
   3996 			if (*p == '$') {
   3997 			    Buf_AddBytes(&buf, p - str, str);
   3998 			    str = p;
   3999 			    continue;
   4000 			}
   4001 
   4002 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
   4003 			    var[p - str - 2] != '\0') {
   4004 			    /*
   4005 			     * Not the variable we want to expand, scan
   4006 			     * until the next variable
   4007 			     */
   4008 			    for (;*p != '$' && *p != '\0'; p++)
   4009 				continue;
   4010 			    Buf_AddBytes(&buf, p - str, str);
   4011 			    str = p;
   4012 			    expand = FALSE;
   4013 			}
   4014 			else
   4015 			    expand = TRUE;
   4016 			break;
   4017 		    }
   4018 		}
   4019 		if (!expand)
   4020 		    continue;
   4021 	    }
   4022 
   4023 	    val = Var_Parse(str, ctxt, undefErr, &length, &freeIt);
   4024 
   4025 	    /*
   4026 	     * When we come down here, val should either point to the
   4027 	     * value of this variable, suitably modified, or be NULL.
   4028 	     * Length should be the total length of the potential
   4029 	     * variable invocation (from $ to end character...)
   4030 	     */
   4031 	    if (val == var_Error || val == varNoError) {
   4032 		/*
   4033 		 * If performing old-time variable substitution, skip over
   4034 		 * the variable and continue with the substitution. Otherwise,
   4035 		 * store the dollar sign and advance str so we continue with
   4036 		 * the string...
   4037 		 */
   4038 		if (oldVars) {
   4039 		    str += length;
   4040 		} else if (undefErr) {
   4041 		    /*
   4042 		     * If variable is undefined, complain and skip the
   4043 		     * variable. The complaint will stop us from doing anything
   4044 		     * when the file is parsed.
   4045 		     */
   4046 		    if (!errorReported) {
   4047 			Parse_Error(PARSE_FATAL,
   4048 				     "Undefined variable \"%.*s\"",length,str);
   4049 		    }
   4050 		    str += length;
   4051 		    errorReported = TRUE;
   4052 		} else {
   4053 		    Buf_AddByte(&buf, *str);
   4054 		    str += 1;
   4055 		}
   4056 	    } else {
   4057 		/*
   4058 		 * We've now got a variable structure to store in. But first,
   4059 		 * advance the string pointer.
   4060 		 */
   4061 		str += length;
   4062 
   4063 		/*
   4064 		 * Copy all the characters from the variable value straight
   4065 		 * into the new string.
   4066 		 */
   4067 		length = strlen(val);
   4068 		Buf_AddBytes(&buf, length, val);
   4069 		trailingBslash = length > 0 && val[length - 1] == '\\';
   4070 	    }
   4071 	    if (freeIt) {
   4072 		free(freeIt);
   4073 		freeIt = NULL;
   4074 	    }
   4075 	}
   4076     }
   4077 
   4078     return Buf_DestroyCompact(&buf);
   4079 }
   4080 
   4081 /*-
   4082  *-----------------------------------------------------------------------
   4083  * Var_GetTail --
   4084  *	Return the tail from each of a list of words. Used to set the
   4085  *	System V local variables.
   4086  *
   4087  * Input:
   4088  *	file		Filename to modify
   4089  *
   4090  * Results:
   4091  *	The resulting string.
   4092  *
   4093  * Side Effects:
   4094  *	None.
   4095  *
   4096  *-----------------------------------------------------------------------
   4097  */
   4098 #if 0
   4099 char *
   4100 Var_GetTail(char *file)
   4101 {
   4102     return(VarModify(file, VarTail, NULL));
   4103 }
   4104 
   4105 /*-
   4106  *-----------------------------------------------------------------------
   4107  * Var_GetHead --
   4108  *	Find the leading components of a (list of) filename(s).
   4109  *	XXX: VarHead does not replace foo by ., as (sun) System V make
   4110  *	does.
   4111  *
   4112  * Input:
   4113  *	file		Filename to manipulate
   4114  *
   4115  * Results:
   4116  *	The leading components.
   4117  *
   4118  * Side Effects:
   4119  *	None.
   4120  *
   4121  *-----------------------------------------------------------------------
   4122  */
   4123 char *
   4124 Var_GetHead(char *file)
   4125 {
   4126     return(VarModify(file, VarHead, NULL));
   4127 }
   4128 #endif
   4129 
   4130 /*-
   4131  *-----------------------------------------------------------------------
   4132  * Var_Init --
   4133  *	Initialize the module
   4134  *
   4135  * Results:
   4136  *	None
   4137  *
   4138  * Side Effects:
   4139  *	The VAR_CMD and VAR_GLOBAL contexts are created
   4140  *-----------------------------------------------------------------------
   4141  */
   4142 void
   4143 Var_Init(void)
   4144 {
   4145     VAR_GLOBAL = Targ_NewGN("Global");
   4146     VAR_CMD = Targ_NewGN("Command");
   4147 
   4148 }
   4149 
   4150 
   4151 void
   4152 Var_End(void)
   4153 {
   4154 }
   4155 
   4156 
   4157 /****************** PRINT DEBUGGING INFO *****************/
   4158 static void
   4159 VarPrintVar(void *vp)
   4160 {
   4161     Var    *v = (Var *)vp;
   4162     fprintf(debug_file, "%-16s = %s\n", v->name, Buf_GetAll(&v->val, NULL));
   4163 }
   4164 
   4165 /*-
   4166  *-----------------------------------------------------------------------
   4167  * Var_Dump --
   4168  *	print all variables in a context
   4169  *-----------------------------------------------------------------------
   4170  */
   4171 void
   4172 Var_Dump(GNode *ctxt)
   4173 {
   4174     Hash_Search search;
   4175     Hash_Entry *h;
   4176 
   4177     for (h = Hash_EnumFirst(&ctxt->context, &search);
   4178 	 h != NULL;
   4179 	 h = Hash_EnumNext(&search)) {
   4180 	    VarPrintVar(Hash_GetValue(h));
   4181     }
   4182 }
   4183