Home | History | Annotate | Line # | Download | only in make
var.c revision 1.165
      1 /*	$NetBSD: var.c,v 1.165 2011/04/11 14:49:09 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 1.165 2011/04/11 14:49:09 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 1.165 2011/04/11 14:49:09 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 
    136 #include    "make.h"
    137 #include    "buf.h"
    138 #include    "dir.h"
    139 #include    "job.h"
    140 
    141 /*
    142  * This is a harmless return value for Var_Parse that can be used by Var_Subst
    143  * to determine if there was an error in parsing -- easier than returning
    144  * a flag, as things outside this module don't give a hoot.
    145  */
    146 char 	var_Error[] = "";
    147 
    148 /*
    149  * Similar to var_Error, but returned when the 'errnum' flag for Var_Parse is
    150  * set false. Why not just use a constant? Well, gcc likes to condense
    151  * identical string instances...
    152  */
    153 static char	varNoError[] = "";
    154 
    155 /*
    156  * Internally, variables are contained in four different contexts.
    157  *	1) the environment. They may not be changed. If an environment
    158  *	    variable is appended-to, the result is placed in the global
    159  *	    context.
    160  *	2) the global context. Variables set in the Makefile are located in
    161  *	    the global context. It is the penultimate context searched when
    162  *	    substituting.
    163  *	3) the command-line context. All variables set on the command line
    164  *	   are placed in this context. They are UNALTERABLE once placed here.
    165  *	4) the local context. Each target has associated with it a context
    166  *	   list. On this list are located the structures describing such
    167  *	   local variables as $(@) and $(*)
    168  * The four contexts are searched in the reverse order from which they are
    169  * listed.
    170  */
    171 GNode          *VAR_GLOBAL;   /* variables from the makefile */
    172 GNode          *VAR_CMD;      /* variables defined on the command-line */
    173 
    174 #define FIND_CMD	0x1   /* look in VAR_CMD when searching */
    175 #define FIND_GLOBAL	0x2   /* look in VAR_GLOBAL as well */
    176 #define FIND_ENV  	0x4   /* look in the environment also */
    177 
    178 typedef struct Var {
    179     char          *name;	/* the variable's name */
    180     Buffer	  val;		/* its value */
    181     int		  flags;    	/* miscellaneous status flags */
    182 #define VAR_IN_USE	1   	    /* Variable's value currently being used.
    183 				     * Used to avoid recursion */
    184 #define VAR_FROM_ENV	2   	    /* Variable comes from the environment */
    185 #define VAR_JUNK  	4   	    /* Variable is a junk variable that
    186 				     * should be destroyed when done with
    187 				     * it. Used by Var_Parse for undefined,
    188 				     * modified variables */
    189 #define VAR_KEEP	8	    /* Variable is VAR_JUNK, but we found
    190 				     * a use for it in some modifier and
    191 				     * the value is therefore valid */
    192 #define VAR_EXPORTED	16 	    /* Variable is exported */
    193 #define VAR_REEXPORT	32	    /* Indicate if var needs re-export.
    194 				     * This would be true if it contains $'s
    195 				     */
    196 #define VAR_FROM_CMD	64 	    /* Variable came from command line */
    197 }  Var;
    198 
    199 /*
    200  * Exporting vars is expensive so skip it if we can
    201  */
    202 #define VAR_EXPORTED_NONE	0
    203 #define VAR_EXPORTED_YES	1
    204 #define VAR_EXPORTED_ALL	2
    205 static int var_exportedVars = VAR_EXPORTED_NONE;
    206 /*
    207  * We pass this to Var_Export when doing the initial export
    208  * or after updating an exported var.
    209  */
    210 #define VAR_EXPORT_PARENT 1
    211 
    212 /* Var*Pattern flags */
    213 #define VAR_SUB_GLOBAL	0x01	/* Apply substitution globally */
    214 #define VAR_SUB_ONE	0x02	/* Apply substitution to one word */
    215 #define VAR_SUB_MATCHED	0x04	/* There was a match */
    216 #define VAR_MATCH_START	0x08	/* Match at start of word */
    217 #define VAR_MATCH_END	0x10	/* Match at end of word */
    218 #define VAR_NOSUBST	0x20	/* don't expand vars in VarGetPattern */
    219 
    220 /* Var_Set flags */
    221 #define VAR_NO_EXPORT	0x01	/* do not export */
    222 
    223 typedef struct {
    224     /*
    225      * The following fields are set by Var_Parse() when it
    226      * encounters modifiers that need to keep state for use by
    227      * subsequent modifiers within the same variable expansion.
    228      */
    229     Byte	varSpace;	/* Word separator in expansions */
    230     Boolean	oneBigWord;	/* TRUE if we will treat the variable as a
    231 				 * single big word, even if it contains
    232 				 * embedded spaces (as opposed to the
    233 				 * usual behaviour of treating it as
    234 				 * several space-separated words). */
    235 } Var_Parse_State;
    236 
    237 /* struct passed as 'void *' to VarSubstitute() for ":S/lhs/rhs/",
    238  * to VarSYSVMatch() for ":lhs=rhs". */
    239 typedef struct {
    240     const char   *lhs;	    /* String to match */
    241     int		  leftLen; /* Length of string */
    242     const char   *rhs;	    /* Replacement string (w/ &'s removed) */
    243     int		  rightLen; /* Length of replacement */
    244     int		  flags;
    245 } VarPattern;
    246 
    247 /* struct passed as 'void *' to VarLoopExpand() for ":@tvar@str@" */
    248 typedef struct {
    249     GNode	*ctxt;		/* variable context */
    250     char	*tvar;		/* name of temp var */
    251     int		tvarLen;
    252     char	*str;		/* string to expand */
    253     int		strLen;
    254     int		errnum;		/* errnum for not defined */
    255 } VarLoop_t;
    256 
    257 #ifndef NO_REGEX
    258 /* struct passed as 'void *' to VarRESubstitute() for ":C///" */
    259 typedef struct {
    260     regex_t	   re;
    261     int		   nsub;
    262     regmatch_t 	  *matches;
    263     char 	  *replace;
    264     int		   flags;
    265 } VarREPattern;
    266 #endif
    267 
    268 /* struct passed to VarSelectWords() for ":[start..end]" */
    269 typedef struct {
    270     int		start;		/* first word to select */
    271     int		end;		/* last word to select */
    272 } VarSelectWords_t;
    273 
    274 static Var *VarFind(const char *, GNode *, int);
    275 static void VarAdd(const char *, const char *, GNode *);
    276 static Boolean VarHead(GNode *, Var_Parse_State *,
    277 			char *, Boolean, Buffer *, void *);
    278 static Boolean VarTail(GNode *, Var_Parse_State *,
    279 			char *, Boolean, Buffer *, void *);
    280 static Boolean VarSuffix(GNode *, Var_Parse_State *,
    281 			char *, Boolean, Buffer *, void *);
    282 static Boolean VarRoot(GNode *, Var_Parse_State *,
    283 			char *, Boolean, Buffer *, void *);
    284 static Boolean VarMatch(GNode *, Var_Parse_State *,
    285 			char *, Boolean, Buffer *, void *);
    286 #ifdef SYSVVARSUB
    287 static Boolean VarSYSVMatch(GNode *, Var_Parse_State *,
    288 			char *, Boolean, Buffer *, void *);
    289 #endif
    290 static Boolean VarNoMatch(GNode *, Var_Parse_State *,
    291 			char *, Boolean, Buffer *, void *);
    292 #ifndef NO_REGEX
    293 static void VarREError(int, regex_t *, const char *);
    294 static Boolean VarRESubstitute(GNode *, Var_Parse_State *,
    295 			char *, Boolean, Buffer *, void *);
    296 #endif
    297 static Boolean VarSubstitute(GNode *, Var_Parse_State *,
    298 			char *, Boolean, Buffer *, void *);
    299 static Boolean VarLoopExpand(GNode *, Var_Parse_State *,
    300 			char *, Boolean, Buffer *, void *);
    301 static char *VarGetPattern(GNode *, Var_Parse_State *,
    302 			   int, const char **, int, int *, int *,
    303 			   VarPattern *);
    304 static char *VarQuote(char *);
    305 static char *VarChangeCase(char *, int);
    306 static char *VarHash(char *);
    307 static char *VarModify(GNode *, Var_Parse_State *,
    308     const char *,
    309     Boolean (*)(GNode *, Var_Parse_State *, char *, Boolean, Buffer *, void *),
    310     void *);
    311 static char *VarOrder(const char *, const char);
    312 static char *VarUniq(const char *);
    313 static int VarWordCompare(const void *, const void *);
    314 static void VarPrintVar(void *);
    315 
    316 #define BROPEN	'{'
    317 #define BRCLOSE	'}'
    318 #define PROPEN	'('
    319 #define PRCLOSE	')'
    320 
    321 /*-
    322  *-----------------------------------------------------------------------
    323  * VarFind --
    324  *	Find the given variable in the given context and any other contexts
    325  *	indicated.
    326  *
    327  * Input:
    328  *	name		name to find
    329  *	ctxt		context in which to find it
    330  *	flags		FIND_GLOBAL set means to look in the
    331  *			VAR_GLOBAL context as well. FIND_CMD set means
    332  *			to look in the VAR_CMD context also. FIND_ENV
    333  *			set means to look in the environment
    334  *
    335  * Results:
    336  *	A pointer to the structure describing the desired variable or
    337  *	NULL if the variable does not exist.
    338  *
    339  * Side Effects:
    340  *	None
    341  *-----------------------------------------------------------------------
    342  */
    343 static Var *
    344 VarFind(const char *name, GNode *ctxt, int flags)
    345 {
    346     Hash_Entry         	*var;
    347     Var			*v;
    348 
    349 	/*
    350 	 * If the variable name begins with a '.', it could very well be one of
    351 	 * the local ones.  We check the name against all the local variables
    352 	 * and substitute the short version in for 'name' if it matches one of
    353 	 * them.
    354 	 */
    355 	if (*name == '.' && isupper((unsigned char) name[1]))
    356 		switch (name[1]) {
    357 		case 'A':
    358 			if (!strcmp(name, ".ALLSRC"))
    359 				name = ALLSRC;
    360 			if (!strcmp(name, ".ARCHIVE"))
    361 				name = ARCHIVE;
    362 			break;
    363 		case 'I':
    364 			if (!strcmp(name, ".IMPSRC"))
    365 				name = IMPSRC;
    366 			break;
    367 		case 'M':
    368 			if (!strcmp(name, ".MEMBER"))
    369 				name = MEMBER;
    370 			break;
    371 		case 'O':
    372 			if (!strcmp(name, ".OODATE"))
    373 				name = OODATE;
    374 			break;
    375 		case 'P':
    376 			if (!strcmp(name, ".PREFIX"))
    377 				name = PREFIX;
    378 			break;
    379 		case 'T':
    380 			if (!strcmp(name, ".TARGET"))
    381 				name = TARGET;
    382 			break;
    383 		}
    384 #ifdef notyet
    385     /* for compatibility with gmake */
    386     if (name[0] == '^' && name[1] == '\0')
    387 	    name = ALLSRC;
    388 #endif
    389 
    390     /*
    391      * First look for the variable in the given context. If it's not there,
    392      * look for it in VAR_CMD, VAR_GLOBAL and the environment, in that order,
    393      * depending on the FIND_* flags in 'flags'
    394      */
    395     var = Hash_FindEntry(&ctxt->context, name);
    396 
    397     if ((var == NULL) && (flags & FIND_CMD) && (ctxt != VAR_CMD)) {
    398 	var = Hash_FindEntry(&VAR_CMD->context, name);
    399     }
    400     if (!checkEnvFirst && (var == NULL) && (flags & FIND_GLOBAL) &&
    401 	(ctxt != VAR_GLOBAL))
    402     {
    403 	var = Hash_FindEntry(&VAR_GLOBAL->context, name);
    404     }
    405     if ((var == NULL) && (flags & FIND_ENV)) {
    406 	char *env;
    407 
    408 	if ((env = getenv(name)) != NULL) {
    409 	    int		len;
    410 
    411 	    v = bmake_malloc(sizeof(Var));
    412 	    v->name = bmake_strdup(name);
    413 
    414 	    len = strlen(env);
    415 
    416 	    Buf_Init(&v->val, len + 1);
    417 	    Buf_AddBytes(&v->val, len, env);
    418 
    419 	    v->flags = VAR_FROM_ENV;
    420 	    return (v);
    421 	} else if (checkEnvFirst && (flags & FIND_GLOBAL) &&
    422 		   (ctxt != VAR_GLOBAL))
    423 	{
    424 	    var = Hash_FindEntry(&VAR_GLOBAL->context, name);
    425 	    if (var == NULL) {
    426 		return NULL;
    427 	    } else {
    428 		return ((Var *)Hash_GetValue(var));
    429 	    }
    430 	} else {
    431 	    return NULL;
    432 	}
    433     } else if (var == NULL) {
    434 	return NULL;
    435     } else {
    436 	return ((Var *)Hash_GetValue(var));
    437     }
    438 }
    439 
    440 /*-
    441  *-----------------------------------------------------------------------
    442  * VarFreeEnv  --
    443  *	If the variable is an environment variable, free it
    444  *
    445  * Input:
    446  *	v		the variable
    447  *	destroy		true if the value buffer should be destroyed.
    448  *
    449  * Results:
    450  *	1 if it is an environment variable 0 ow.
    451  *
    452  * Side Effects:
    453  *	The variable is free'ed if it is an environent variable.
    454  *-----------------------------------------------------------------------
    455  */
    456 static Boolean
    457 VarFreeEnv(Var *v, Boolean destroy)
    458 {
    459     if ((v->flags & VAR_FROM_ENV) == 0)
    460 	return FALSE;
    461     free(v->name);
    462     Buf_Destroy(&v->val, destroy);
    463     free(v);
    464     return TRUE;
    465 }
    466 
    467 /*-
    468  *-----------------------------------------------------------------------
    469  * VarAdd  --
    470  *	Add a new variable of name name and value val to the given context
    471  *
    472  * Input:
    473  *	name		name of variable to add
    474  *	val		value to set it to
    475  *	ctxt		context in which to set it
    476  *
    477  * Results:
    478  *	None
    479  *
    480  * Side Effects:
    481  *	The new variable is placed at the front of the given context
    482  *	The name and val arguments are duplicated so they may
    483  *	safely be freed.
    484  *-----------------------------------------------------------------------
    485  */
    486 static void
    487 VarAdd(const char *name, const char *val, GNode *ctxt)
    488 {
    489     Var   	  *v;
    490     int		  len;
    491     Hash_Entry    *h;
    492 
    493     v = bmake_malloc(sizeof(Var));
    494 
    495     len = val ? strlen(val) : 0;
    496     Buf_Init(&v->val, len+1);
    497     Buf_AddBytes(&v->val, len, val);
    498 
    499     v->flags = 0;
    500 
    501     h = Hash_CreateEntry(&ctxt->context, name, NULL);
    502     Hash_SetValue(h, v);
    503     v->name = h->name;
    504     if (DEBUG(VAR)) {
    505 	fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
    506     }
    507 }
    508 
    509 /*-
    510  *-----------------------------------------------------------------------
    511  * Var_Delete --
    512  *	Remove a variable from a context.
    513  *
    514  * Results:
    515  *	None.
    516  *
    517  * Side Effects:
    518  *	The Var structure is removed and freed.
    519  *
    520  *-----------------------------------------------------------------------
    521  */
    522 void
    523 Var_Delete(const char *name, GNode *ctxt)
    524 {
    525     Hash_Entry 	  *ln;
    526 
    527     ln = Hash_FindEntry(&ctxt->context, name);
    528     if (DEBUG(VAR)) {
    529 	fprintf(debug_file, "%s:delete %s%s\n",
    530 	    ctxt->name, name, ln ? "" : " (not found)");
    531     }
    532     if (ln != NULL) {
    533 	Var 	  *v;
    534 
    535 	v = (Var *)Hash_GetValue(ln);
    536 	if ((v->flags & VAR_EXPORTED)) {
    537 	    unsetenv(v->name);
    538 	}
    539 	if (strcmp(MAKE_EXPORTED, v->name) == 0) {
    540 	    var_exportedVars = VAR_EXPORTED_NONE;
    541 	}
    542 	if (v->name != ln->name)
    543 		free(v->name);
    544 	Hash_DeleteEntry(&ctxt->context, ln);
    545 	Buf_Destroy(&v->val, TRUE);
    546 	free(v);
    547     }
    548 }
    549 
    550 
    551 /*
    552  * Export a var.
    553  * We ignore make internal variables (those which start with '.')
    554  * Also we jump through some hoops to avoid calling setenv
    555  * more than necessary since it can leak.
    556  * We only manipulate flags of vars if 'parent' is set.
    557  */
    558 static int
    559 Var_Export1(const char *name, int parent)
    560 {
    561     char tmp[BUFSIZ];
    562     Var *v;
    563     char *val = NULL;
    564     int n;
    565 
    566     if (*name == '.')
    567 	return 0;			/* skip internals */
    568     if (!name[1]) {
    569 	/*
    570 	 * A single char.
    571 	 * If it is one of the vars that should only appear in
    572 	 * local context, skip it, else we can get Var_Subst
    573 	 * into a loop.
    574 	 */
    575 	switch (name[0]) {
    576 	case '@':
    577 	case '%':
    578 	case '*':
    579 	case '!':
    580 	    return 0;
    581 	}
    582     }
    583     v = VarFind(name, VAR_GLOBAL, 0);
    584     if (v == NULL) {
    585 	return 0;
    586     }
    587     if (!parent &&
    588 	(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
    589 	return 0;			/* nothing to do */
    590     }
    591     val = Buf_GetAll(&v->val, NULL);
    592     if (strchr(val, '$')) {
    593 	if (parent) {
    594 	    /*
    595 	     * Flag this as something we need to re-export.
    596 	     * No point actually exporting it now though,
    597 	     * the child can do it at the last minute.
    598 	     */
    599 	    v->flags |= (VAR_EXPORTED|VAR_REEXPORT);
    600 	    return 1;
    601 	}
    602 	if (v->flags & VAR_IN_USE) {
    603 	    /*
    604 	     * We recursed while exporting in a child.
    605 	     * This isn't going to end well, just skip it.
    606 	     */
    607 	    return 0;
    608 	}
    609 	n = snprintf(tmp, sizeof(tmp), "${%s}", name);
    610 	if (n < (int)sizeof(tmp)) {
    611 	    val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    612 	    setenv(name, val, 1);
    613 	    free(val);
    614 	}
    615     } else {
    616 	if (parent) {
    617 	    v->flags &= ~VAR_REEXPORT;	/* once will do */
    618 	}
    619 	if (parent || !(v->flags & VAR_EXPORTED)) {
    620 	    setenv(name, val, 1);
    621 	}
    622     }
    623     /*
    624      * This is so Var_Set knows to call Var_Export again...
    625      */
    626     if (parent) {
    627 	v->flags |= VAR_EXPORTED;
    628     }
    629     return 1;
    630 }
    631 
    632 /*
    633  * This gets called from our children.
    634  */
    635 void
    636 Var_ExportVars(void)
    637 {
    638     char tmp[BUFSIZ];
    639     Hash_Entry         	*var;
    640     Hash_Search 	state;
    641     Var *v;
    642     char *val;
    643     int n;
    644 
    645     if (VAR_EXPORTED_NONE == var_exportedVars)
    646 	return;
    647 
    648     if (VAR_EXPORTED_ALL == var_exportedVars) {
    649 	/*
    650 	 * Ouch! This is crazy...
    651 	 */
    652 	for (var = Hash_EnumFirst(&VAR_GLOBAL->context, &state);
    653 	     var != NULL;
    654 	     var = Hash_EnumNext(&state)) {
    655 	    v = (Var *)Hash_GetValue(var);
    656 	    Var_Export1(v->name, 0);
    657 	}
    658 	return;
    659     }
    660     /*
    661      * We have a number of exported vars,
    662      */
    663     n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
    664     if (n < (int)sizeof(tmp)) {
    665 	char **av;
    666 	char *as;
    667 	int ac;
    668 	int i;
    669 
    670 	val = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    671 	av = brk_string(val, &ac, FALSE, &as);
    672 	for (i = 0; i < ac; i++) {
    673 	    Var_Export1(av[i], 0);
    674 	}
    675 	free(val);
    676 	free(as);
    677 	free(av);
    678     }
    679 }
    680 
    681 /*
    682  * This is called when .export is seen or
    683  * .MAKE.EXPORTED is modified.
    684  * It is also called when any exported var is modified.
    685  */
    686 void
    687 Var_Export(char *str, int isExport)
    688 {
    689     char *name;
    690     char *val;
    691     char **av;
    692     char *as;
    693     int track;
    694     int ac;
    695     int i;
    696 
    697     if (isExport && (!str || !str[0])) {
    698 	var_exportedVars = VAR_EXPORTED_ALL; /* use with caution! */
    699 	return;
    700     }
    701 
    702     if (strncmp(str, "-env", 4) == 0) {
    703 	track = 0;
    704 	str += 4;
    705     } else {
    706 	track = VAR_EXPORT_PARENT;
    707     }
    708     val = Var_Subst(NULL, str, VAR_GLOBAL, 0);
    709     av = brk_string(val, &ac, FALSE, &as);
    710     for (i = 0; i < ac; i++) {
    711 	name = av[i];
    712 	if (!name[1]) {
    713 	    /*
    714 	     * A single char.
    715 	     * If it is one of the vars that should only appear in
    716 	     * local context, skip it, else we can get Var_Subst
    717 	     * into a loop.
    718 	     */
    719 	    switch (name[0]) {
    720 	    case '@':
    721 	    case '%':
    722 	    case '*':
    723 	    case '!':
    724 		continue;
    725 	    }
    726 	}
    727 	if (Var_Export1(name, track)) {
    728 	    if (VAR_EXPORTED_ALL != var_exportedVars)
    729 		var_exportedVars = VAR_EXPORTED_YES;
    730 	    if (isExport && track) {
    731 		Var_Append(MAKE_EXPORTED, name, VAR_GLOBAL);
    732 	    }
    733 	}
    734     }
    735     free(val);
    736     free(as);
    737     free(av);
    738 }
    739 
    740 
    741 /*
    742  * This is called when .unexport[-env] is seen.
    743  */
    744 void
    745 Var_UnExport(char *str)
    746 {
    747     char tmp[BUFSIZ];
    748     char *vlist;
    749     char *cp;
    750     Boolean unexport_env;
    751     int n;
    752 
    753     if (!str || !str[0]) {
    754 	return; 			/* assert? */
    755     }
    756 
    757     vlist = NULL;
    758 
    759     str += 8;
    760     unexport_env = (strncmp(str, "-env", 4) == 0);
    761     if (unexport_env) {
    762 	extern char **environ;
    763 	static char **savenv;
    764 	char **newenv;
    765 
    766 	cp = getenv(MAKE_LEVEL);	/* we should preserve this */
    767 	if (environ == savenv) {
    768 	    /* we have been here before! */
    769 	    newenv = bmake_realloc(environ, 2 * sizeof(char *));
    770 	} else {
    771 	    if (savenv) {
    772 		free(savenv);
    773 		savenv = NULL;
    774 	    }
    775 	    newenv = bmake_malloc(2 * sizeof(char *));
    776 	}
    777 	if (!newenv)
    778 	    return;
    779 	/* Note: we cannot safely free() the original environ. */
    780 	environ = savenv = newenv;
    781 	newenv[0] = NULL;
    782 	newenv[1] = NULL;
    783 	setenv(MAKE_LEVEL, cp, 1);
    784     } else {
    785 	for (; *str != '\n' && isspace((unsigned char) *str); str++)
    786 	    continue;
    787 	if (str[0] && str[0] != '\n') {
    788 	    vlist = str;
    789 	}
    790     }
    791 
    792     if (!vlist) {
    793 	/* Using .MAKE.EXPORTED */
    794 	n = snprintf(tmp, sizeof(tmp), "${" MAKE_EXPORTED ":O:u}");
    795 	if (n < (int)sizeof(tmp)) {
    796 	    vlist = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    797 	}
    798     }
    799     if (vlist) {
    800 	Var *v;
    801 	char **av;
    802 	char *as;
    803 	int ac;
    804 	int i;
    805 
    806 	av = brk_string(vlist, &ac, FALSE, &as);
    807 	for (i = 0; i < ac; i++) {
    808 	    v = VarFind(av[i], VAR_GLOBAL, 0);
    809 	    if (!v)
    810 		continue;
    811 	    if (!unexport_env &&
    812 		(v->flags & (VAR_EXPORTED|VAR_REEXPORT)) == VAR_EXPORTED) {
    813 		unsetenv(v->name);
    814 	    }
    815 	    v->flags &= ~(VAR_EXPORTED|VAR_REEXPORT);
    816 	    /*
    817 	     * If we are unexporting a list,
    818 	     * remove each one from .MAKE.EXPORTED.
    819 	     * If we are removing them all,
    820 	     * just delete .MAKE.EXPORTED below.
    821 	     */
    822 	    if (vlist == str) {
    823 		n = snprintf(tmp, sizeof(tmp),
    824 			     "${" MAKE_EXPORTED ":N%s}", v->name);
    825 		if (n < (int)sizeof(tmp)) {
    826 		    cp = Var_Subst(NULL, tmp, VAR_GLOBAL, 0);
    827 		    Var_Set(MAKE_EXPORTED, cp, VAR_GLOBAL, 0);
    828 		    free(cp);
    829 		}
    830 	    }
    831 	}
    832 	free(as);
    833 	free(av);
    834 	if (vlist != str) {
    835 	    Var_Delete(MAKE_EXPORTED, VAR_GLOBAL);
    836 	    free(vlist);
    837 	}
    838     }
    839 }
    840 
    841 /*-
    842  *-----------------------------------------------------------------------
    843  * Var_Set --
    844  *	Set the variable name to the value val in the given context.
    845  *
    846  * Input:
    847  *	name		name of variable to set
    848  *	val		value to give to the variable
    849  *	ctxt		context in which to set it
    850  *
    851  * Results:
    852  *	None.
    853  *
    854  * Side Effects:
    855  *	If the variable doesn't yet exist, a new record is created for it.
    856  *	Else the old value is freed and the new one stuck in its place
    857  *
    858  * Notes:
    859  *	The variable is searched for only in its context before being
    860  *	created in that context. I.e. if the context is VAR_GLOBAL,
    861  *	only VAR_GLOBAL->context is searched. Likewise if it is VAR_CMD, only
    862  *	VAR_CMD->context is searched. This is done to avoid the literally
    863  *	thousands of unnecessary strcmp's that used to be done to
    864  *	set, say, $(@) or $(<).
    865  *	If the context is VAR_GLOBAL though, we check if the variable
    866  *	was set in VAR_CMD from the command line and skip it if so.
    867  *-----------------------------------------------------------------------
    868  */
    869 void
    870 Var_Set(const char *name, const char *val, GNode *ctxt, int flags)
    871 {
    872     Var   *v;
    873     char *expanded_name = NULL;
    874 
    875     /*
    876      * We only look for a variable in the given context since anything set
    877      * here will override anything in a lower context, so there's not much
    878      * point in searching them all just to save a bit of memory...
    879      */
    880     if (strchr(name, '$') != NULL) {
    881 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
    882 	if (expanded_name[0] == 0) {
    883 	    if (DEBUG(VAR)) {
    884 		fprintf(debug_file, "Var_Set(\"%s\", \"%s\", ...) "
    885 			"name expands to empty string - ignored\n",
    886 			name, val);
    887 	    }
    888 	    free(expanded_name);
    889 	    return;
    890 	}
    891 	name = expanded_name;
    892     }
    893     if (ctxt == VAR_GLOBAL) {
    894 	v = VarFind(name, VAR_CMD, 0);
    895 	if (v != NULL) {
    896 	    if ((v->flags & VAR_FROM_CMD)) {
    897 		if (DEBUG(VAR)) {
    898 		    fprintf(debug_file, "%s:%s = %s ignored!\n", ctxt->name, name, val);
    899 		}
    900 		goto out;
    901 	    }
    902 	    VarFreeEnv(v, TRUE);
    903 	}
    904     }
    905     v = VarFind(name, ctxt, 0);
    906     if (v == NULL) {
    907 	VarAdd(name, val, ctxt);
    908     } else {
    909 	Buf_Empty(&v->val);
    910 	Buf_AddBytes(&v->val, strlen(val), val);
    911 
    912 	if (DEBUG(VAR)) {
    913 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name, val);
    914 	}
    915 	if ((v->flags & VAR_EXPORTED)) {
    916 	    Var_Export1(name, VAR_EXPORT_PARENT);
    917 	}
    918     }
    919     /*
    920      * Any variables given on the command line are automatically exported
    921      * to the environment (as per POSIX standard)
    922      */
    923     if (ctxt == VAR_CMD && (flags & VAR_NO_EXPORT) == 0) {
    924 	if (v == NULL) {
    925 	    /* we just added it */
    926 	    v = VarFind(name, ctxt, 0);
    927 	}
    928 	if (v != NULL)
    929 	    v->flags |= VAR_FROM_CMD;
    930 	/*
    931 	 * If requested, don't export these in the environment
    932 	 * individually.  We still put them in MAKEOVERRIDES so
    933 	 * that the command-line settings continue to override
    934 	 * Makefile settings.
    935 	 */
    936 	if (varNoExportEnv != TRUE)
    937 	    setenv(name, val, 1);
    938 
    939 	Var_Append(MAKEOVERRIDES, name, VAR_GLOBAL);
    940     }
    941     /*
    942      * Another special case.
    943      * Several make's support this sort of mechanism for tracking
    944      * recursion - but each uses a different name.
    945      * We allow the makefiles to update .MAKE.LEVEL and ensure
    946      * children see a correctly incremented value.
    947      */
    948     if (ctxt == VAR_GLOBAL && strcmp(MAKE_LEVEL, name) == 0) {
    949 	char tmp[64];
    950 	int level;
    951 
    952 	level = atoi(val);
    953 	snprintf(tmp, sizeof(tmp), "%u", level + 1);
    954 	setenv(MAKE_LEVEL, tmp, 1);
    955     }
    956 
    957 
    958  out:
    959     if (expanded_name != NULL)
    960 	free(expanded_name);
    961     if (v != NULL)
    962 	VarFreeEnv(v, TRUE);
    963 }
    964 
    965 /*-
    966  *-----------------------------------------------------------------------
    967  * Var_Append --
    968  *	The variable of the given name has the given value appended to it in
    969  *	the given context.
    970  *
    971  * Input:
    972  *	name		name of variable to modify
    973  *	val		String to append to it
    974  *	ctxt		Context in which this should occur
    975  *
    976  * Results:
    977  *	None
    978  *
    979  * Side Effects:
    980  *	If the variable doesn't exist, it is created. Else the strings
    981  *	are concatenated (with a space in between).
    982  *
    983  * Notes:
    984  *	Only if the variable is being sought in the global context is the
    985  *	environment searched.
    986  *	XXX: Knows its calling circumstances in that if called with ctxt
    987  *	an actual target, it will only search that context since only
    988  *	a local variable could be being appended to. This is actually
    989  *	a big win and must be tolerated.
    990  *-----------------------------------------------------------------------
    991  */
    992 void
    993 Var_Append(const char *name, const char *val, GNode *ctxt)
    994 {
    995     Var		   *v;
    996     Hash_Entry	   *h;
    997     char *expanded_name = NULL;
    998 
    999     if (strchr(name, '$') != NULL) {
   1000 	expanded_name = Var_Subst(NULL, name, ctxt, 0);
   1001 	if (expanded_name[0] == 0) {
   1002 	    if (DEBUG(VAR)) {
   1003 		fprintf(debug_file, "Var_Append(\"%s\", \"%s\", ...) "
   1004 			"name expands to empty string - ignored\n",
   1005 			name, val);
   1006 	    }
   1007 	    free(expanded_name);
   1008 	    return;
   1009 	}
   1010 	name = expanded_name;
   1011     }
   1012 
   1013     v = VarFind(name, ctxt, (ctxt == VAR_GLOBAL) ? FIND_ENV : 0);
   1014 
   1015     if (v == NULL) {
   1016 	VarAdd(name, val, ctxt);
   1017     } else {
   1018 	Buf_AddByte(&v->val, ' ');
   1019 	Buf_AddBytes(&v->val, strlen(val), val);
   1020 
   1021 	if (DEBUG(VAR)) {
   1022 	    fprintf(debug_file, "%s:%s = %s\n", ctxt->name, name,
   1023 		   Buf_GetAll(&v->val, NULL));
   1024 	}
   1025 
   1026 	if (v->flags & VAR_FROM_ENV) {
   1027 	    /*
   1028 	     * If the original variable came from the environment, we
   1029 	     * have to install it in the global context (we could place
   1030 	     * it in the environment, but then we should provide a way to
   1031 	     * export other variables...)
   1032 	     */
   1033 	    v->flags &= ~VAR_FROM_ENV;
   1034 	    h = Hash_CreateEntry(&ctxt->context, name, NULL);
   1035 	    Hash_SetValue(h, v);
   1036 	}
   1037     }
   1038     if (expanded_name != NULL)
   1039 	free(expanded_name);
   1040 }
   1041 
   1042 /*-
   1043  *-----------------------------------------------------------------------
   1044  * Var_Exists --
   1045  *	See if the given variable exists.
   1046  *
   1047  * Input:
   1048  *	name		Variable to find
   1049  *	ctxt		Context in which to start search
   1050  *
   1051  * Results:
   1052  *	TRUE if it does, FALSE if it doesn't
   1053  *
   1054  * Side Effects:
   1055  *	None.
   1056  *
   1057  *-----------------------------------------------------------------------
   1058  */
   1059 Boolean
   1060 Var_Exists(const char *name, GNode *ctxt)
   1061 {
   1062     Var		  *v;
   1063     char          *cp;
   1064 
   1065     if ((cp = strchr(name, '$')) != NULL) {
   1066 	cp = Var_Subst(NULL, name, ctxt, FALSE);
   1067     }
   1068     v = VarFind(cp ? cp : name, ctxt, FIND_CMD|FIND_GLOBAL|FIND_ENV);
   1069     if (cp != NULL) {
   1070 	free(cp);
   1071     }
   1072     if (v == NULL) {
   1073 	return(FALSE);
   1074     } else {
   1075 	(void)VarFreeEnv(v, TRUE);
   1076     }
   1077     return(TRUE);
   1078 }
   1079 
   1080 /*-
   1081  *-----------------------------------------------------------------------
   1082  * Var_Value --
   1083  *	Return the value of the named variable in the given context
   1084  *
   1085  * Input:
   1086  *	name		name to find
   1087  *	ctxt		context in which to search for it
   1088  *
   1089  * Results:
   1090  *	The value if the variable exists, NULL if it doesn't
   1091  *
   1092  * Side Effects:
   1093  *	None
   1094  *-----------------------------------------------------------------------
   1095  */
   1096 char *
   1097 Var_Value(const char *name, GNode *ctxt, char **frp)
   1098 {
   1099     Var            *v;
   1100 
   1101     v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   1102     *frp = NULL;
   1103     if (v != NULL) {
   1104 	char *p = (Buf_GetAll(&v->val, NULL));
   1105 	if (VarFreeEnv(v, FALSE))
   1106 	    *frp = p;
   1107 	return p;
   1108     } else {
   1109 	return NULL;
   1110     }
   1111 }
   1112 
   1113 /*-
   1114  *-----------------------------------------------------------------------
   1115  * VarHead --
   1116  *	Remove the tail of the given word and place the result in the given
   1117  *	buffer.
   1118  *
   1119  * Input:
   1120  *	word		Word to trim
   1121  *	addSpace	True if need to add a space to the buffer
   1122  *			before sticking in the head
   1123  *	buf		Buffer in which to store it
   1124  *
   1125  * Results:
   1126  *	TRUE if characters were added to the buffer (a space needs to be
   1127  *	added to the buffer before the next word).
   1128  *
   1129  * Side Effects:
   1130  *	The trimmed word is added to the buffer.
   1131  *
   1132  *-----------------------------------------------------------------------
   1133  */
   1134 static Boolean
   1135 VarHead(GNode *ctx __unused, Var_Parse_State *vpstate,
   1136 	char *word, Boolean addSpace, Buffer *buf,
   1137 	void *dummy)
   1138 {
   1139     char *slash;
   1140 
   1141     slash = strrchr(word, '/');
   1142     if (slash != NULL) {
   1143 	if (addSpace && vpstate->varSpace) {
   1144 	    Buf_AddByte(buf, vpstate->varSpace);
   1145 	}
   1146 	*slash = '\0';
   1147 	Buf_AddBytes(buf, strlen(word), word);
   1148 	*slash = '/';
   1149 	return (TRUE);
   1150     } else {
   1151 	/*
   1152 	 * If no directory part, give . (q.v. the POSIX standard)
   1153 	 */
   1154 	if (addSpace && vpstate->varSpace)
   1155 	    Buf_AddByte(buf, vpstate->varSpace);
   1156 	Buf_AddByte(buf, '.');
   1157     }
   1158     return(dummy ? TRUE : TRUE);
   1159 }
   1160 
   1161 /*-
   1162  *-----------------------------------------------------------------------
   1163  * VarTail --
   1164  *	Remove the head of the given word and place the result in the given
   1165  *	buffer.
   1166  *
   1167  * Input:
   1168  *	word		Word to trim
   1169  *	addSpace	True if need to add a space to the buffer
   1170  *			before adding the tail
   1171  *	buf		Buffer in which to store it
   1172  *
   1173  * Results:
   1174  *	TRUE if characters were added to the buffer (a space needs to be
   1175  *	added to the buffer before the next word).
   1176  *
   1177  * Side Effects:
   1178  *	The trimmed word is added to the buffer.
   1179  *
   1180  *-----------------------------------------------------------------------
   1181  */
   1182 static Boolean
   1183 VarTail(GNode *ctx __unused, Var_Parse_State *vpstate,
   1184 	char *word, Boolean addSpace, Buffer *buf,
   1185 	void *dummy)
   1186 {
   1187     char *slash;
   1188 
   1189     if (addSpace && vpstate->varSpace) {
   1190 	Buf_AddByte(buf, vpstate->varSpace);
   1191     }
   1192 
   1193     slash = strrchr(word, '/');
   1194     if (slash != NULL) {
   1195 	*slash++ = '\0';
   1196 	Buf_AddBytes(buf, strlen(slash), slash);
   1197 	slash[-1] = '/';
   1198     } else {
   1199 	Buf_AddBytes(buf, strlen(word), word);
   1200     }
   1201     return (dummy ? TRUE : TRUE);
   1202 }
   1203 
   1204 /*-
   1205  *-----------------------------------------------------------------------
   1206  * VarSuffix --
   1207  *	Place the suffix of the given word in the given buffer.
   1208  *
   1209  * Input:
   1210  *	word		Word to trim
   1211  *	addSpace	TRUE if need to add a space before placing the
   1212  *			suffix in the buffer
   1213  *	buf		Buffer in which to store it
   1214  *
   1215  * Results:
   1216  *	TRUE if characters were added to the buffer (a space needs to be
   1217  *	added to the buffer before the next word).
   1218  *
   1219  * Side Effects:
   1220  *	The suffix from the word is placed in the buffer.
   1221  *
   1222  *-----------------------------------------------------------------------
   1223  */
   1224 static Boolean
   1225 VarSuffix(GNode *ctx __unused, Var_Parse_State *vpstate,
   1226 	  char *word, Boolean addSpace, Buffer *buf,
   1227 	  void *dummy)
   1228 {
   1229     char *dot;
   1230 
   1231     dot = strrchr(word, '.');
   1232     if (dot != NULL) {
   1233 	if (addSpace && vpstate->varSpace) {
   1234 	    Buf_AddByte(buf, vpstate->varSpace);
   1235 	}
   1236 	*dot++ = '\0';
   1237 	Buf_AddBytes(buf, strlen(dot), dot);
   1238 	dot[-1] = '.';
   1239 	addSpace = TRUE;
   1240     }
   1241     return (dummy ? addSpace : addSpace);
   1242 }
   1243 
   1244 /*-
   1245  *-----------------------------------------------------------------------
   1246  * VarRoot --
   1247  *	Remove the suffix of the given word and place the result in the
   1248  *	buffer.
   1249  *
   1250  * Input:
   1251  *	word		Word to trim
   1252  *	addSpace	TRUE if need to add a space to the buffer
   1253  *			before placing the root in it
   1254  *	buf		Buffer in which to store it
   1255  *
   1256  * Results:
   1257  *	TRUE if characters were added to the buffer (a space needs to be
   1258  *	added to the buffer before the next word).
   1259  *
   1260  * Side Effects:
   1261  *	The trimmed word is added to the buffer.
   1262  *
   1263  *-----------------------------------------------------------------------
   1264  */
   1265 static Boolean
   1266 VarRoot(GNode *ctx __unused, Var_Parse_State *vpstate,
   1267 	char *word, Boolean addSpace, Buffer *buf,
   1268 	void *dummy)
   1269 {
   1270     char *dot;
   1271 
   1272     if (addSpace && vpstate->varSpace) {
   1273 	Buf_AddByte(buf, vpstate->varSpace);
   1274     }
   1275 
   1276     dot = strrchr(word, '.');
   1277     if (dot != NULL) {
   1278 	*dot = '\0';
   1279 	Buf_AddBytes(buf, strlen(word), word);
   1280 	*dot = '.';
   1281     } else {
   1282 	Buf_AddBytes(buf, strlen(word), word);
   1283     }
   1284     return (dummy ? TRUE : TRUE);
   1285 }
   1286 
   1287 /*-
   1288  *-----------------------------------------------------------------------
   1289  * VarMatch --
   1290  *	Place the word in the buffer if it matches the given pattern.
   1291  *	Callback function for VarModify to implement the :M modifier.
   1292  *
   1293  * Input:
   1294  *	word		Word to examine
   1295  *	addSpace	TRUE if need to add a space to the buffer
   1296  *			before adding the word, if it matches
   1297  *	buf		Buffer in which to store it
   1298  *	pattern		Pattern the word must match
   1299  *
   1300  * Results:
   1301  *	TRUE if a space should be placed in the buffer before the next
   1302  *	word.
   1303  *
   1304  * Side Effects:
   1305  *	The word may be copied to the buffer.
   1306  *
   1307  *-----------------------------------------------------------------------
   1308  */
   1309 static Boolean
   1310 VarMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
   1311 	 char *word, Boolean addSpace, Buffer *buf,
   1312 	 void *pattern)
   1313 {
   1314     if (DEBUG(VAR))
   1315 	fprintf(debug_file, "VarMatch [%s] [%s]\n", word, (char *)pattern);
   1316     if (Str_Match(word, (char *)pattern)) {
   1317 	if (addSpace && vpstate->varSpace) {
   1318 	    Buf_AddByte(buf, vpstate->varSpace);
   1319 	}
   1320 	addSpace = TRUE;
   1321 	Buf_AddBytes(buf, strlen(word), word);
   1322     }
   1323     return(addSpace);
   1324 }
   1325 
   1326 #ifdef SYSVVARSUB
   1327 /*-
   1328  *-----------------------------------------------------------------------
   1329  * VarSYSVMatch --
   1330  *	Place the word in the buffer if it matches the given pattern.
   1331  *	Callback function for VarModify to implement the System V %
   1332  *	modifiers.
   1333  *
   1334  * Input:
   1335  *	word		Word to examine
   1336  *	addSpace	TRUE if need to add a space to the buffer
   1337  *			before adding the word, if it matches
   1338  *	buf		Buffer in which to store it
   1339  *	patp		Pattern the word must match
   1340  *
   1341  * Results:
   1342  *	TRUE if a space should be placed in the buffer before the next
   1343  *	word.
   1344  *
   1345  * Side Effects:
   1346  *	The word may be copied to the buffer.
   1347  *
   1348  *-----------------------------------------------------------------------
   1349  */
   1350 static Boolean
   1351 VarSYSVMatch(GNode *ctx, Var_Parse_State *vpstate,
   1352 	     char *word, Boolean addSpace, Buffer *buf,
   1353 	     void *patp)
   1354 {
   1355     int len;
   1356     char *ptr;
   1357     VarPattern 	  *pat = (VarPattern *)patp;
   1358     char *varexp;
   1359 
   1360     if (addSpace && vpstate->varSpace)
   1361 	Buf_AddByte(buf, vpstate->varSpace);
   1362 
   1363     addSpace = TRUE;
   1364 
   1365     if ((ptr = Str_SYSVMatch(word, pat->lhs, &len)) != NULL) {
   1366         varexp = Var_Subst(NULL, pat->rhs, ctx, 0);
   1367 	Str_SYSVSubst(buf, varexp, ptr, len);
   1368 	free(varexp);
   1369     } else {
   1370 	Buf_AddBytes(buf, strlen(word), word);
   1371     }
   1372 
   1373     return(addSpace);
   1374 }
   1375 #endif
   1376 
   1377 
   1378 /*-
   1379  *-----------------------------------------------------------------------
   1380  * VarNoMatch --
   1381  *	Place the word in the buffer if it doesn't match the given pattern.
   1382  *	Callback function for VarModify to implement the :N modifier.
   1383  *
   1384  * Input:
   1385  *	word		Word to examine
   1386  *	addSpace	TRUE if need to add a space to the buffer
   1387  *			before adding the word, if it matches
   1388  *	buf		Buffer in which to store it
   1389  *	pattern		Pattern the word must match
   1390  *
   1391  * Results:
   1392  *	TRUE if a space should be placed in the buffer before the next
   1393  *	word.
   1394  *
   1395  * Side Effects:
   1396  *	The word may be copied to the buffer.
   1397  *
   1398  *-----------------------------------------------------------------------
   1399  */
   1400 static Boolean
   1401 VarNoMatch(GNode *ctx __unused, Var_Parse_State *vpstate,
   1402 	   char *word, Boolean addSpace, Buffer *buf,
   1403 	   void *pattern)
   1404 {
   1405     if (!Str_Match(word, (char *)pattern)) {
   1406 	if (addSpace && vpstate->varSpace) {
   1407 	    Buf_AddByte(buf, vpstate->varSpace);
   1408 	}
   1409 	addSpace = TRUE;
   1410 	Buf_AddBytes(buf, strlen(word), word);
   1411     }
   1412     return(addSpace);
   1413 }
   1414 
   1415 
   1416 /*-
   1417  *-----------------------------------------------------------------------
   1418  * VarSubstitute --
   1419  *	Perform a string-substitution on the given word, placing the
   1420  *	result in the passed buffer.
   1421  *
   1422  * Input:
   1423  *	word		Word to modify
   1424  *	addSpace	True if space should be added before
   1425  *			other characters
   1426  *	buf		Buffer for result
   1427  *	patternp	Pattern for substitution
   1428  *
   1429  * Results:
   1430  *	TRUE if a space is needed before more characters are added.
   1431  *
   1432  * Side Effects:
   1433  *	None.
   1434  *
   1435  *-----------------------------------------------------------------------
   1436  */
   1437 static Boolean
   1438 VarSubstitute(GNode *ctx __unused, Var_Parse_State *vpstate,
   1439 	      char *word, Boolean addSpace, Buffer *buf,
   1440 	      void *patternp)
   1441 {
   1442     int  	wordLen;    /* Length of word */
   1443     char 	*cp;	    /* General pointer */
   1444     VarPattern	*pattern = (VarPattern *)patternp;
   1445 
   1446     wordLen = strlen(word);
   1447     if ((pattern->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) !=
   1448 	(VAR_SUB_ONE|VAR_SUB_MATCHED)) {
   1449 	/*
   1450 	 * Still substituting -- break it down into simple anchored cases
   1451 	 * and if none of them fits, perform the general substitution case.
   1452 	 */
   1453 	if ((pattern->flags & VAR_MATCH_START) &&
   1454 	    (strncmp(word, pattern->lhs, pattern->leftLen) == 0)) {
   1455 		/*
   1456 		 * Anchored at start and beginning of word matches pattern
   1457 		 */
   1458 		if ((pattern->flags & VAR_MATCH_END) &&
   1459 		    (wordLen == pattern->leftLen)) {
   1460 			/*
   1461 			 * Also anchored at end and matches to the end (word
   1462 			 * is same length as pattern) add space and rhs only
   1463 			 * if rhs is non-null.
   1464 			 */
   1465 			if (pattern->rightLen != 0) {
   1466 			    if (addSpace && vpstate->varSpace) {
   1467 				Buf_AddByte(buf, vpstate->varSpace);
   1468 			    }
   1469 			    addSpace = TRUE;
   1470 			    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1471 			}
   1472 			pattern->flags |= VAR_SUB_MATCHED;
   1473 		} else if (pattern->flags & VAR_MATCH_END) {
   1474 		    /*
   1475 		     * Doesn't match to end -- copy word wholesale
   1476 		     */
   1477 		    goto nosub;
   1478 		} else {
   1479 		    /*
   1480 		     * Matches at start but need to copy in trailing characters
   1481 		     */
   1482 		    if ((pattern->rightLen + wordLen - pattern->leftLen) != 0){
   1483 			if (addSpace && vpstate->varSpace) {
   1484 			    Buf_AddByte(buf, vpstate->varSpace);
   1485 			}
   1486 			addSpace = TRUE;
   1487 		    }
   1488 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1489 		    Buf_AddBytes(buf, wordLen - pattern->leftLen,
   1490 				 (word + pattern->leftLen));
   1491 		    pattern->flags |= VAR_SUB_MATCHED;
   1492 		}
   1493 	} else if (pattern->flags & VAR_MATCH_START) {
   1494 	    /*
   1495 	     * Had to match at start of word and didn't -- copy whole word.
   1496 	     */
   1497 	    goto nosub;
   1498 	} else if (pattern->flags & VAR_MATCH_END) {
   1499 	    /*
   1500 	     * Anchored at end, Find only place match could occur (leftLen
   1501 	     * characters from the end of the word) and see if it does. Note
   1502 	     * that because the $ will be left at the end of the lhs, we have
   1503 	     * to use strncmp.
   1504 	     */
   1505 	    cp = word + (wordLen - pattern->leftLen);
   1506 	    if ((cp >= word) &&
   1507 		(strncmp(cp, pattern->lhs, pattern->leftLen) == 0)) {
   1508 		/*
   1509 		 * Match found. If we will place characters in the buffer,
   1510 		 * add a space before hand as indicated by addSpace, then
   1511 		 * stuff in the initial, unmatched part of the word followed
   1512 		 * by the right-hand-side.
   1513 		 */
   1514 		if (((cp - word) + pattern->rightLen) != 0) {
   1515 		    if (addSpace && vpstate->varSpace) {
   1516 			Buf_AddByte(buf, vpstate->varSpace);
   1517 		    }
   1518 		    addSpace = TRUE;
   1519 		}
   1520 		Buf_AddBytes(buf, cp - word, word);
   1521 		Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1522 		pattern->flags |= VAR_SUB_MATCHED;
   1523 	    } else {
   1524 		/*
   1525 		 * Had to match at end and didn't. Copy entire word.
   1526 		 */
   1527 		goto nosub;
   1528 	    }
   1529 	} else {
   1530 	    /*
   1531 	     * Pattern is unanchored: search for the pattern in the word using
   1532 	     * String_FindSubstring, copying unmatched portions and the
   1533 	     * right-hand-side for each match found, handling non-global
   1534 	     * substitutions correctly, etc. When the loop is done, any
   1535 	     * remaining part of the word (word and wordLen are adjusted
   1536 	     * accordingly through the loop) is copied straight into the
   1537 	     * buffer.
   1538 	     * addSpace is set FALSE as soon as a space is added to the
   1539 	     * buffer.
   1540 	     */
   1541 	    Boolean done;
   1542 	    int origSize;
   1543 
   1544 	    done = FALSE;
   1545 	    origSize = Buf_Size(buf);
   1546 	    while (!done) {
   1547 		cp = Str_FindSubstring(word, pattern->lhs);
   1548 		if (cp != NULL) {
   1549 		    if (addSpace && (((cp - word) + pattern->rightLen) != 0)){
   1550 			Buf_AddByte(buf, vpstate->varSpace);
   1551 			addSpace = FALSE;
   1552 		    }
   1553 		    Buf_AddBytes(buf, cp-word, word);
   1554 		    Buf_AddBytes(buf, pattern->rightLen, pattern->rhs);
   1555 		    wordLen -= (cp - word) + pattern->leftLen;
   1556 		    word = cp + pattern->leftLen;
   1557 		    if (wordLen == 0) {
   1558 			done = TRUE;
   1559 		    }
   1560 		    if ((pattern->flags & VAR_SUB_GLOBAL) == 0) {
   1561 			done = TRUE;
   1562 		    }
   1563 		    pattern->flags |= VAR_SUB_MATCHED;
   1564 		} else {
   1565 		    done = TRUE;
   1566 		}
   1567 	    }
   1568 	    if (wordLen != 0) {
   1569 		if (addSpace && vpstate->varSpace) {
   1570 		    Buf_AddByte(buf, vpstate->varSpace);
   1571 		}
   1572 		Buf_AddBytes(buf, wordLen, word);
   1573 	    }
   1574 	    /*
   1575 	     * If added characters to the buffer, need to add a space
   1576 	     * before we add any more. If we didn't add any, just return
   1577 	     * the previous value of addSpace.
   1578 	     */
   1579 	    return ((Buf_Size(buf) != origSize) || addSpace);
   1580 	}
   1581 	return (addSpace);
   1582     }
   1583  nosub:
   1584     if (addSpace && vpstate->varSpace) {
   1585 	Buf_AddByte(buf, vpstate->varSpace);
   1586     }
   1587     Buf_AddBytes(buf, wordLen, word);
   1588     return(TRUE);
   1589 }
   1590 
   1591 #ifndef NO_REGEX
   1592 /*-
   1593  *-----------------------------------------------------------------------
   1594  * VarREError --
   1595  *	Print the error caused by a regcomp or regexec call.
   1596  *
   1597  * Results:
   1598  *	None.
   1599  *
   1600  * Side Effects:
   1601  *	An error gets printed.
   1602  *
   1603  *-----------------------------------------------------------------------
   1604  */
   1605 static void
   1606 VarREError(int errnum, regex_t *pat, const char *str)
   1607 {
   1608     char *errbuf;
   1609     int errlen;
   1610 
   1611     errlen = regerror(errnum, pat, 0, 0);
   1612     errbuf = bmake_malloc(errlen);
   1613     regerror(errnum, pat, errbuf, errlen);
   1614     Error("%s: %s", str, errbuf);
   1615     free(errbuf);
   1616 }
   1617 
   1618 
   1619 /*-
   1620  *-----------------------------------------------------------------------
   1621  * VarRESubstitute --
   1622  *	Perform a regex substitution on the given word, placing the
   1623  *	result in the passed buffer.
   1624  *
   1625  * Results:
   1626  *	TRUE if a space is needed before more characters are added.
   1627  *
   1628  * Side Effects:
   1629  *	None.
   1630  *
   1631  *-----------------------------------------------------------------------
   1632  */
   1633 static Boolean
   1634 VarRESubstitute(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
   1635 		char *word, Boolean addSpace, Buffer *buf,
   1636 		void *patternp)
   1637 {
   1638     VarREPattern *pat;
   1639     int xrv;
   1640     char *wp;
   1641     char *rp;
   1642     int added;
   1643     int flags = 0;
   1644 
   1645 #define MAYBE_ADD_SPACE()		\
   1646 	if (addSpace && !added)		\
   1647 	    Buf_AddByte(buf, ' ');	\
   1648 	added = 1
   1649 
   1650     added = 0;
   1651     wp = word;
   1652     pat = patternp;
   1653 
   1654     if ((pat->flags & (VAR_SUB_ONE|VAR_SUB_MATCHED)) ==
   1655 	(VAR_SUB_ONE|VAR_SUB_MATCHED))
   1656 	xrv = REG_NOMATCH;
   1657     else {
   1658     tryagain:
   1659 	xrv = regexec(&pat->re, wp, pat->nsub, pat->matches, flags);
   1660     }
   1661 
   1662     switch (xrv) {
   1663     case 0:
   1664 	pat->flags |= VAR_SUB_MATCHED;
   1665 	if (pat->matches[0].rm_so > 0) {
   1666 	    MAYBE_ADD_SPACE();
   1667 	    Buf_AddBytes(buf, pat->matches[0].rm_so, wp);
   1668 	}
   1669 
   1670 	for (rp = pat->replace; *rp; rp++) {
   1671 	    if ((*rp == '\\') && ((rp[1] == '&') || (rp[1] == '\\'))) {
   1672 		MAYBE_ADD_SPACE();
   1673 		Buf_AddByte(buf,rp[1]);
   1674 		rp++;
   1675 	    }
   1676 	    else if ((*rp == '&') ||
   1677 		((*rp == '\\') && isdigit((unsigned char)rp[1]))) {
   1678 		int n;
   1679 		const char *subbuf;
   1680 		int sublen;
   1681 		char errstr[3];
   1682 
   1683 		if (*rp == '&') {
   1684 		    n = 0;
   1685 		    errstr[0] = '&';
   1686 		    errstr[1] = '\0';
   1687 		} else {
   1688 		    n = rp[1] - '0';
   1689 		    errstr[0] = '\\';
   1690 		    errstr[1] = rp[1];
   1691 		    errstr[2] = '\0';
   1692 		    rp++;
   1693 		}
   1694 
   1695 		if (n > pat->nsub) {
   1696 		    Error("No subexpression %s", &errstr[0]);
   1697 		    subbuf = "";
   1698 		    sublen = 0;
   1699 		} else if ((pat->matches[n].rm_so == -1) &&
   1700 			   (pat->matches[n].rm_eo == -1)) {
   1701 		    Error("No match for subexpression %s", &errstr[0]);
   1702 		    subbuf = "";
   1703 		    sublen = 0;
   1704 	        } else {
   1705 		    subbuf = wp + pat->matches[n].rm_so;
   1706 		    sublen = pat->matches[n].rm_eo - pat->matches[n].rm_so;
   1707 		}
   1708 
   1709 		if (sublen > 0) {
   1710 		    MAYBE_ADD_SPACE();
   1711 		    Buf_AddBytes(buf, sublen, subbuf);
   1712 		}
   1713 	    } else {
   1714 		MAYBE_ADD_SPACE();
   1715 		Buf_AddByte(buf, *rp);
   1716 	    }
   1717 	}
   1718 	wp += pat->matches[0].rm_eo;
   1719 	if (pat->flags & VAR_SUB_GLOBAL) {
   1720 	    flags |= REG_NOTBOL;
   1721 	    if (pat->matches[0].rm_so == 0 && pat->matches[0].rm_eo == 0) {
   1722 		MAYBE_ADD_SPACE();
   1723 		Buf_AddByte(buf, *wp);
   1724 		wp++;
   1725 
   1726 	    }
   1727 	    if (*wp)
   1728 		goto tryagain;
   1729 	}
   1730 	if (*wp) {
   1731 	    MAYBE_ADD_SPACE();
   1732 	    Buf_AddBytes(buf, strlen(wp), wp);
   1733 	}
   1734 	break;
   1735     default:
   1736 	VarREError(xrv, &pat->re, "Unexpected regex error");
   1737        /* fall through */
   1738     case REG_NOMATCH:
   1739 	if (*wp) {
   1740 	    MAYBE_ADD_SPACE();
   1741 	    Buf_AddBytes(buf,strlen(wp),wp);
   1742 	}
   1743 	break;
   1744     }
   1745     return(addSpace||added);
   1746 }
   1747 #endif
   1748 
   1749 
   1750 
   1751 /*-
   1752  *-----------------------------------------------------------------------
   1753  * VarLoopExpand --
   1754  *	Implements the :@<temp>@<string>@ modifier of ODE make.
   1755  *	We set the temp variable named in pattern.lhs to word and expand
   1756  *	pattern.rhs storing the result in the passed buffer.
   1757  *
   1758  * Input:
   1759  *	word		Word to modify
   1760  *	addSpace	True if space should be added before
   1761  *			other characters
   1762  *	buf		Buffer for result
   1763  *	pattern		Datafor substitution
   1764  *
   1765  * Results:
   1766  *	TRUE if a space is needed before more characters are added.
   1767  *
   1768  * Side Effects:
   1769  *	None.
   1770  *
   1771  *-----------------------------------------------------------------------
   1772  */
   1773 static Boolean
   1774 VarLoopExpand(GNode *ctx __unused, Var_Parse_State *vpstate __unused,
   1775 	      char *word, Boolean addSpace, Buffer *buf,
   1776 	      void *loopp)
   1777 {
   1778     VarLoop_t	*loop = (VarLoop_t *)loopp;
   1779     char *s;
   1780     int slen;
   1781 
   1782     if (word && *word) {
   1783         Var_Set(loop->tvar, word, loop->ctxt, VAR_NO_EXPORT);
   1784         s = Var_Subst(NULL, loop->str, loop->ctxt, loop->errnum);
   1785         if (s != NULL && *s != '\0') {
   1786             if (addSpace && *s != '\n')
   1787                 Buf_AddByte(buf, ' ');
   1788             Buf_AddBytes(buf, (slen = strlen(s)), s);
   1789             addSpace = (slen > 0 && s[slen - 1] != '\n');
   1790             free(s);
   1791         }
   1792     }
   1793     return addSpace;
   1794 }
   1795 
   1796 
   1797 /*-
   1798  *-----------------------------------------------------------------------
   1799  * VarSelectWords --
   1800  *	Implements the :[start..end] modifier.
   1801  *	This is a special case of VarModify since we want to be able
   1802  *	to scan the list backwards if start > end.
   1803  *
   1804  * Input:
   1805  *	str		String whose words should be trimmed
   1806  *	seldata		words to select
   1807  *
   1808  * Results:
   1809  *	A string of all the words selected.
   1810  *
   1811  * Side Effects:
   1812  *	None.
   1813  *
   1814  *-----------------------------------------------------------------------
   1815  */
   1816 static char *
   1817 VarSelectWords(GNode *ctx __unused, Var_Parse_State *vpstate,
   1818 	       const char *str, VarSelectWords_t *seldata)
   1819 {
   1820     Buffer  	  buf;		    /* Buffer for the new string */
   1821     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
   1822 				     * buffer before adding the trimmed
   1823 				     * word */
   1824     char **av;			    /* word list */
   1825     char *as;			    /* word list memory */
   1826     int ac, i;
   1827     int start, end, step;
   1828 
   1829     Buf_Init(&buf, 0);
   1830     addSpace = FALSE;
   1831 
   1832     if (vpstate->oneBigWord) {
   1833 	/* fake what brk_string() would do if there were only one word */
   1834 	ac = 1;
   1835     	av = bmake_malloc((ac + 1) * sizeof(char *));
   1836 	as = bmake_strdup(str);
   1837 	av[0] = as;
   1838 	av[1] = NULL;
   1839     } else {
   1840 	av = brk_string(str, &ac, FALSE, &as);
   1841     }
   1842 
   1843     /*
   1844      * Now sanitize seldata.
   1845      * If seldata->start or seldata->end are negative, convert them to
   1846      * the positive equivalents (-1 gets converted to argc, -2 gets
   1847      * converted to (argc-1), etc.).
   1848      */
   1849     if (seldata->start < 0)
   1850 	seldata->start = ac + seldata->start + 1;
   1851     if (seldata->end < 0)
   1852 	seldata->end = ac + seldata->end + 1;
   1853 
   1854     /*
   1855      * We avoid scanning more of the list than we need to.
   1856      */
   1857     if (seldata->start > seldata->end) {
   1858 	start = MIN(ac, seldata->start) - 1;
   1859 	end = MAX(0, seldata->end - 1);
   1860 	step = -1;
   1861     } else {
   1862 	start = MAX(0, seldata->start - 1);
   1863 	end = MIN(ac, seldata->end);
   1864 	step = 1;
   1865     }
   1866 
   1867     for (i = start;
   1868 	 (step < 0 && i >= end) || (step > 0 && i < end);
   1869 	 i += step) {
   1870 	if (av[i] && *av[i]) {
   1871 	    if (addSpace && vpstate->varSpace) {
   1872 		Buf_AddByte(&buf, vpstate->varSpace);
   1873 	    }
   1874 	    Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   1875 	    addSpace = TRUE;
   1876 	}
   1877     }
   1878 
   1879     free(as);
   1880     free(av);
   1881 
   1882     return Buf_Destroy(&buf, FALSE);
   1883 }
   1884 
   1885 
   1886 /*-
   1887  * VarRealpath --
   1888  *	Replace each word with the result of realpath()
   1889  *	if successful.
   1890  */
   1891 static Boolean
   1892 VarRealpath(GNode *ctx __unused, Var_Parse_State *vpstate,
   1893 	    char *word, Boolean addSpace, Buffer *buf,
   1894 	    void *patternp __unused)
   1895 {
   1896 	struct stat st;
   1897 	char rbuf[MAXPATHLEN];
   1898 	char *rp;
   1899 
   1900 	if (addSpace && vpstate->varSpace) {
   1901 	    Buf_AddByte(buf, vpstate->varSpace);
   1902 	}
   1903 	addSpace = TRUE;
   1904 	rp = realpath(word, rbuf);
   1905 	if (rp && *rp == '/' && stat(rp, &st) == 0)
   1906 		word = rp;
   1907 
   1908 	Buf_AddBytes(buf, strlen(word), word);
   1909 	return(addSpace);
   1910 }
   1911 
   1912 /*-
   1913  *-----------------------------------------------------------------------
   1914  * VarModify --
   1915  *	Modify each of the words of the passed string using the given
   1916  *	function. Used to implement all modifiers.
   1917  *
   1918  * Input:
   1919  *	str		String whose words should be trimmed
   1920  *	modProc		Function to use to modify them
   1921  *	datum		Datum to pass it
   1922  *
   1923  * Results:
   1924  *	A string of all the words modified appropriately.
   1925  *
   1926  * Side Effects:
   1927  *	None.
   1928  *
   1929  *-----------------------------------------------------------------------
   1930  */
   1931 static char *
   1932 VarModify(GNode *ctx, Var_Parse_State *vpstate,
   1933     const char *str,
   1934     Boolean (*modProc)(GNode *, Var_Parse_State *, char *,
   1935 		       Boolean, Buffer *, void *),
   1936     void *datum)
   1937 {
   1938     Buffer  	  buf;		    /* Buffer for the new string */
   1939     Boolean 	  addSpace; 	    /* TRUE if need to add a space to the
   1940 				     * buffer before adding the trimmed
   1941 				     * word */
   1942     char **av;			    /* word list */
   1943     char *as;			    /* word list memory */
   1944     int ac, i;
   1945 
   1946     Buf_Init(&buf, 0);
   1947     addSpace = FALSE;
   1948 
   1949     if (vpstate->oneBigWord) {
   1950 	/* fake what brk_string() would do if there were only one word */
   1951 	ac = 1;
   1952     	av = bmake_malloc((ac + 1) * sizeof(char *));
   1953 	as = bmake_strdup(str);
   1954 	av[0] = as;
   1955 	av[1] = NULL;
   1956     } else {
   1957 	av = brk_string(str, &ac, FALSE, &as);
   1958     }
   1959 
   1960     for (i = 0; i < ac; i++) {
   1961 	addSpace = (*modProc)(ctx, vpstate, av[i], addSpace, &buf, datum);
   1962     }
   1963 
   1964     free(as);
   1965     free(av);
   1966 
   1967     return Buf_Destroy(&buf, FALSE);
   1968 }
   1969 
   1970 
   1971 static int
   1972 VarWordCompare(const void *a, const void *b)
   1973 {
   1974 	int r = strcmp(*(const char * const *)a, *(const char * const *)b);
   1975 	return r;
   1976 }
   1977 
   1978 /*-
   1979  *-----------------------------------------------------------------------
   1980  * VarOrder --
   1981  *	Order the words in the string.
   1982  *
   1983  * Input:
   1984  *	str		String whose words should be sorted.
   1985  *	otype		How to order: s - sort, x - random.
   1986  *
   1987  * Results:
   1988  *	A string containing the words ordered.
   1989  *
   1990  * Side Effects:
   1991  *	None.
   1992  *
   1993  *-----------------------------------------------------------------------
   1994  */
   1995 static char *
   1996 VarOrder(const char *str, const char otype)
   1997 {
   1998     Buffer  	  buf;		    /* Buffer for the new string */
   1999     char **av;			    /* word list [first word does not count] */
   2000     char *as;			    /* word list memory */
   2001     int ac, i;
   2002 
   2003     Buf_Init(&buf, 0);
   2004 
   2005     av = brk_string(str, &ac, FALSE, &as);
   2006 
   2007     if (ac > 0)
   2008 	switch (otype) {
   2009 	case 's':	/* sort alphabetically */
   2010 	    qsort(av, ac, sizeof(char *), VarWordCompare);
   2011 	    break;
   2012 	case 'x':	/* randomize */
   2013 	{
   2014 	    int rndidx;
   2015 	    char *t;
   2016 
   2017 	    /*
   2018 	     * We will use [ac..2] range for mod factors. This will produce
   2019 	     * random numbers in [(ac-1)..0] interval, and minimal
   2020 	     * reasonable value for mod factor is 2 (the mod 1 will produce
   2021 	     * 0 with probability 1).
   2022 	     */
   2023 	    for (i = ac-1; i > 0; i--) {
   2024 		rndidx = random() % (i + 1);
   2025 		if (i != rndidx) {
   2026 		    t = av[i];
   2027 		    av[i] = av[rndidx];
   2028 		    av[rndidx] = t;
   2029 		}
   2030 	    }
   2031 	}
   2032 	} /* end of switch */
   2033 
   2034     for (i = 0; i < ac; i++) {
   2035 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   2036 	if (i != ac - 1)
   2037 	    Buf_AddByte(&buf, ' ');
   2038     }
   2039 
   2040     free(as);
   2041     free(av);
   2042 
   2043     return Buf_Destroy(&buf, FALSE);
   2044 }
   2045 
   2046 
   2047 /*-
   2048  *-----------------------------------------------------------------------
   2049  * VarUniq --
   2050  *	Remove adjacent duplicate words.
   2051  *
   2052  * Input:
   2053  *	str		String whose words should be sorted
   2054  *
   2055  * Results:
   2056  *	A string containing the resulting words.
   2057  *
   2058  * Side Effects:
   2059  *	None.
   2060  *
   2061  *-----------------------------------------------------------------------
   2062  */
   2063 static char *
   2064 VarUniq(const char *str)
   2065 {
   2066     Buffer	  buf;		    /* Buffer for new string */
   2067     char 	**av;		    /* List of words to affect */
   2068     char 	 *as;		    /* Word list memory */
   2069     int 	  ac, i, j;
   2070 
   2071     Buf_Init(&buf, 0);
   2072     av = brk_string(str, &ac, FALSE, &as);
   2073 
   2074     if (ac > 1) {
   2075 	for (j = 0, i = 1; i < ac; i++)
   2076 	    if (strcmp(av[i], av[j]) != 0 && (++j != i))
   2077 		av[j] = av[i];
   2078 	ac = j + 1;
   2079     }
   2080 
   2081     for (i = 0; i < ac; i++) {
   2082 	Buf_AddBytes(&buf, strlen(av[i]), av[i]);
   2083 	if (i != ac - 1)
   2084 	    Buf_AddByte(&buf, ' ');
   2085     }
   2086 
   2087     free(as);
   2088     free(av);
   2089 
   2090     return Buf_Destroy(&buf, FALSE);
   2091 }
   2092 
   2093 
   2094 /*-
   2095  *-----------------------------------------------------------------------
   2096  * VarGetPattern --
   2097  *	Pass through the tstr looking for 1) escaped delimiters,
   2098  *	'$'s and backslashes (place the escaped character in
   2099  *	uninterpreted) and 2) unescaped $'s that aren't before
   2100  *	the delimiter (expand the variable substitution unless flags
   2101  *	has VAR_NOSUBST set).
   2102  *	Return the expanded string or NULL if the delimiter was missing
   2103  *	If pattern is specified, handle escaped ampersands, and replace
   2104  *	unescaped ampersands with the lhs of the pattern.
   2105  *
   2106  * Results:
   2107  *	A string of all the words modified appropriately.
   2108  *	If length is specified, return the string length of the buffer
   2109  *	If flags is specified and the last character of the pattern is a
   2110  *	$ set the VAR_MATCH_END bit of flags.
   2111  *
   2112  * Side Effects:
   2113  *	None.
   2114  *-----------------------------------------------------------------------
   2115  */
   2116 static char *
   2117 VarGetPattern(GNode *ctxt, Var_Parse_State *vpstate __unused,
   2118 	      int errnum, const char **tstr, int delim, int *flags,
   2119 	      int *length, VarPattern *pattern)
   2120 {
   2121     const char *cp;
   2122     char *rstr;
   2123     Buffer buf;
   2124     int junk;
   2125 
   2126     Buf_Init(&buf, 0);
   2127     if (length == NULL)
   2128 	length = &junk;
   2129 
   2130 #define IS_A_MATCH(cp, delim) \
   2131     ((cp[0] == '\\') && ((cp[1] == delim) ||  \
   2132      (cp[1] == '\\') || (cp[1] == '$') || (pattern && (cp[1] == '&'))))
   2133 
   2134     /*
   2135      * Skim through until the matching delimiter is found;
   2136      * pick up variable substitutions on the way. Also allow
   2137      * backslashes to quote the delimiter, $, and \, but don't
   2138      * touch other backslashes.
   2139      */
   2140     for (cp = *tstr; *cp && (*cp != delim); cp++) {
   2141 	if (IS_A_MATCH(cp, delim)) {
   2142 	    Buf_AddByte(&buf, cp[1]);
   2143 	    cp++;
   2144 	} else if (*cp == '$') {
   2145 	    if (cp[1] == delim) {
   2146 		if (flags == NULL)
   2147 		    Buf_AddByte(&buf, *cp);
   2148 		else
   2149 		    /*
   2150 		     * Unescaped $ at end of pattern => anchor
   2151 		     * pattern at end.
   2152 		     */
   2153 		    *flags |= VAR_MATCH_END;
   2154 	    } else {
   2155 		if (flags == NULL || (*flags & VAR_NOSUBST) == 0) {
   2156 		    char   *cp2;
   2157 		    int     len;
   2158 		    void   *freeIt;
   2159 
   2160 		    /*
   2161 		     * If unescaped dollar sign not before the
   2162 		     * delimiter, assume it's a variable
   2163 		     * substitution and recurse.
   2164 		     */
   2165 		    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
   2166 		    Buf_AddBytes(&buf, strlen(cp2), cp2);
   2167 		    if (freeIt)
   2168 			free(freeIt);
   2169 		    cp += len - 1;
   2170 		} else {
   2171 		    const char *cp2 = &cp[1];
   2172 
   2173 		    if (*cp2 == PROPEN || *cp2 == BROPEN) {
   2174 			/*
   2175 			 * Find the end of this variable reference
   2176 			 * and suck it in without further ado.
   2177 			 * It will be interperated later.
   2178 			 */
   2179 			int have = *cp2;
   2180 			int want = (*cp2 == PROPEN) ? PRCLOSE : BRCLOSE;
   2181 			int depth = 1;
   2182 
   2183 			for (++cp2; *cp2 != '\0' && depth > 0; ++cp2) {
   2184 			    if (cp2[-1] != '\\') {
   2185 				if (*cp2 == have)
   2186 				    ++depth;
   2187 				if (*cp2 == want)
   2188 				    --depth;
   2189 			    }
   2190 			}
   2191 			Buf_AddBytes(&buf, cp2 - cp, cp);
   2192 			cp = --cp2;
   2193 		    } else
   2194 			Buf_AddByte(&buf, *cp);
   2195 		}
   2196 	    }
   2197 	}
   2198 	else if (pattern && *cp == '&')
   2199 	    Buf_AddBytes(&buf, pattern->leftLen, pattern->lhs);
   2200 	else
   2201 	    Buf_AddByte(&buf, *cp);
   2202     }
   2203 
   2204     if (*cp != delim) {
   2205 	*tstr = cp;
   2206 	*length = 0;
   2207 	return NULL;
   2208     }
   2209 
   2210     *tstr = ++cp;
   2211     *length = Buf_Size(&buf);
   2212     rstr = Buf_Destroy(&buf, FALSE);
   2213     if (DEBUG(VAR))
   2214 	fprintf(debug_file, "Modifier pattern: \"%s\"\n", rstr);
   2215     return rstr;
   2216 }
   2217 
   2218 /*-
   2219  *-----------------------------------------------------------------------
   2220  * VarQuote --
   2221  *	Quote shell meta-characters in the string
   2222  *
   2223  * Results:
   2224  *	The quoted string
   2225  *
   2226  * Side Effects:
   2227  *	None.
   2228  *
   2229  *-----------------------------------------------------------------------
   2230  */
   2231 static char *
   2232 VarQuote(char *str)
   2233 {
   2234 
   2235     Buffer  	  buf;
   2236     /* This should cover most shells :-( */
   2237     static const char meta[] = "\n \t'`\";&<>()|*?{}[]\\$!#^~";
   2238     const char	*newline;
   2239     size_t len, nlen;
   2240 
   2241     if ((newline = Shell_GetNewline()) == NULL)
   2242 	    newline = "\\\n";
   2243     nlen = strlen(newline);
   2244 
   2245     Buf_Init(&buf, 0);
   2246     while (*str != '\0') {
   2247 	if ((len = strcspn(str, meta)) != 0) {
   2248 	    Buf_AddBytes(&buf, len, str);
   2249 	    str += len;
   2250 	} else if (*str == '\n') {
   2251 	    Buf_AddBytes(&buf, nlen, newline);
   2252 	    ++str;
   2253 	} else {
   2254 	    Buf_AddByte(&buf, '\\');
   2255 	    Buf_AddByte(&buf, *str);
   2256 	    ++str;
   2257 	}
   2258     }
   2259     str = Buf_Destroy(&buf, FALSE);
   2260     if (DEBUG(VAR))
   2261 	fprintf(debug_file, "QuoteMeta: [%s]\n", str);
   2262     return str;
   2263 }
   2264 
   2265 /*-
   2266  *-----------------------------------------------------------------------
   2267  * VarHash --
   2268  *      Hash the string using the MurmurHash3 algorithm.
   2269  *      Output is computed using 32bit Little Endian arithmetic.
   2270  *
   2271  * Input:
   2272  *	str		String to modify
   2273  *
   2274  * Results:
   2275  *      Hash value of str, encoded as 8 hex digits.
   2276  *
   2277  * Side Effects:
   2278  *      None.
   2279  *
   2280  *-----------------------------------------------------------------------
   2281  */
   2282 static char *
   2283 VarHash(char *str)
   2284 {
   2285     static const char    hexdigits[16] = "0123456789abcdef";
   2286     Buffer         buf;
   2287     size_t         len, len2;
   2288     unsigned char  *ustr = (unsigned char *)str;
   2289     uint32_t       h, k, c1, c2;
   2290     int            done;
   2291 
   2292     done = 1;
   2293     h  = 0x971e137bU;
   2294     c1 = 0x95543787U;
   2295     c2 = 0x2ad7eb25U;
   2296     len2 = strlen(str);
   2297 
   2298     for (len = len2; len; ) {
   2299 	k = 0;
   2300 	switch (len) {
   2301 	default:
   2302 	    k = (ustr[3] << 24) | (ustr[2] << 16) | (ustr[1] << 8) | ustr[0];
   2303 	    len -= 4;
   2304 	    ustr += 4;
   2305 	    break;
   2306 	case 3:
   2307 	    k |= (ustr[2] << 16);
   2308 	case 2:
   2309 	    k |= (ustr[1] << 8);
   2310 	case 1:
   2311 	    k |= ustr[0];
   2312 	    len = 0;
   2313 	}
   2314 	c1 = c1 * 5 + 0x7b7d159cU;
   2315 	c2 = c2 * 5 + 0x6bce6396U;
   2316 	k *= c1;
   2317 	k = (k << 11) ^ (k >> 21);
   2318 	k *= c2;
   2319 	h = (h << 13) ^ (h >> 19);
   2320 	h = h * 5 + 0x52dce729U;
   2321 	h ^= k;
   2322    } while (!done);
   2323    h ^= len2;
   2324    h *= 0x85ebca6b;
   2325    h ^= h >> 13;
   2326    h *= 0xc2b2ae35;
   2327    h ^= h >> 16;
   2328 
   2329    Buf_Init(&buf, 0);
   2330    for (len = 0; len < 8; ++len) {
   2331        Buf_AddByte(&buf, hexdigits[h & 15]);
   2332        h >>= 4;
   2333    }
   2334 
   2335    return Buf_Destroy(&buf, FALSE);
   2336 }
   2337 
   2338 /*-
   2339  *-----------------------------------------------------------------------
   2340  * VarChangeCase --
   2341  *      Change the string to all uppercase or all lowercase
   2342  *
   2343  * Input:
   2344  *	str		String to modify
   2345  *	upper		TRUE -> uppercase, else lowercase
   2346  *
   2347  * Results:
   2348  *      The string with case changed
   2349  *
   2350  * Side Effects:
   2351  *      None.
   2352  *
   2353  *-----------------------------------------------------------------------
   2354  */
   2355 static char *
   2356 VarChangeCase(char *str, int upper)
   2357 {
   2358    Buffer         buf;
   2359    int            (*modProc)(int);
   2360 
   2361    modProc = (upper ? toupper : tolower);
   2362    Buf_Init(&buf, 0);
   2363    for (; *str ; str++) {
   2364        Buf_AddByte(&buf, modProc(*str));
   2365    }
   2366    return Buf_Destroy(&buf, FALSE);
   2367 }
   2368 
   2369 static char *
   2370 VarStrftime(const char *fmt, int zulu)
   2371 {
   2372     char buf[BUFSIZ];
   2373     time_t utc;
   2374 
   2375     time(&utc);
   2376     if (!*fmt)
   2377 	fmt = "%c";
   2378     strftime(buf, sizeof(buf), fmt, zulu ? gmtime(&utc) : localtime(&utc));
   2379 
   2380     buf[sizeof(buf) - 1] = '\0';
   2381     return bmake_strdup(buf);
   2382 }
   2383 
   2384 /*
   2385  * Now we need to apply any modifiers the user wants applied.
   2386  * These are:
   2387  *  	  :M<pattern>	words which match the given <pattern>.
   2388  *  			<pattern> is of the standard file
   2389  *  			wildcarding form.
   2390  *  	  :N<pattern>	words which do not match the given <pattern>.
   2391  *  	  :S<d><pat1><d><pat2><d>[1gW]
   2392  *  			Substitute <pat2> for <pat1> in the value
   2393  *  	  :C<d><pat1><d><pat2><d>[1gW]
   2394  *  			Substitute <pat2> for regex <pat1> in the value
   2395  *  	  :H		Substitute the head of each word
   2396  *  	  :T		Substitute the tail of each word
   2397  *  	  :E		Substitute the extension (minus '.') of
   2398  *  			each word
   2399  *  	  :R		Substitute the root of each word
   2400  *  			(pathname minus the suffix).
   2401  *	  :O		("Order") Alphabeticaly sort words in variable.
   2402  *	  :Ox		("intermiX") Randomize words in variable.
   2403  *	  :u		("uniq") Remove adjacent duplicate words.
   2404  *	  :tu		Converts the variable contents to uppercase.
   2405  *	  :tl		Converts the variable contents to lowercase.
   2406  *	  :ts[c]	Sets varSpace - the char used to
   2407  *			separate words to 'c'. If 'c' is
   2408  *			omitted then no separation is used.
   2409  *	  :tW		Treat the variable contents as a single
   2410  *			word, even if it contains spaces.
   2411  *			(Mnemonic: one big 'W'ord.)
   2412  *	  :tw		Treat the variable contents as multiple
   2413  *			space-separated words.
   2414  *			(Mnemonic: many small 'w'ords.)
   2415  *	  :[index]	Select a single word from the value.
   2416  *	  :[start..end]	Select multiple words from the value.
   2417  *	  :[*] or :[0]	Select the entire value, as a single
   2418  *			word.  Equivalent to :tW.
   2419  *	  :[@]		Select the entire value, as multiple
   2420  *			words.	Undoes the effect of :[*].
   2421  *			Equivalent to :tw.
   2422  *	  :[#]		Returns the number of words in the value.
   2423  *
   2424  *	  :?<true-value>:<false-value>
   2425  *			If the variable evaluates to true, return
   2426  *			true value, else return the second value.
   2427  *    	  :lhs=rhs  	Like :S, but the rhs goes to the end of
   2428  *    			the invocation.
   2429  *	  :sh		Treat the current value as a command
   2430  *			to be run, new value is its output.
   2431  * The following added so we can handle ODE makefiles.
   2432  *	  :@<tmpvar>@<newval>@
   2433  *			Assign a temporary local variable <tmpvar>
   2434  *			to the current value of each word in turn
   2435  *			and replace each word with the result of
   2436  *			evaluating <newval>
   2437  *	  :D<newval>	Use <newval> as value if variable defined
   2438  *	  :U<newval>	Use <newval> as value if variable undefined
   2439  *	  :L		Use the name of the variable as the value.
   2440  *	  :P		Use the path of the node that has the same
   2441  *			name as the variable as the value.  This
   2442  *			basically includes an implied :L so that
   2443  *			the common method of refering to the path
   2444  *			of your dependent 'x' in a rule is to use
   2445  *			the form '${x:P}'.
   2446  *	  :!<cmd>!	Run cmd much the same as :sh run's the
   2447  *			current value of the variable.
   2448  * The ::= modifiers, actually assign a value to the variable.
   2449  * Their main purpose is in supporting modifiers of .for loop
   2450  * iterators and other obscure uses.  They always expand to
   2451  * nothing.  In a target rule that would otherwise expand to an
   2452  * empty line they can be preceded with @: to keep make happy.
   2453  * Eg.
   2454  *
   2455  * foo:	.USE
   2456  * .for i in ${.TARGET} ${.TARGET:R}.gz
   2457  * 	@: ${t::=$i}
   2458  *	@echo blah ${t:T}
   2459  * .endfor
   2460  *
   2461  *	  ::=<str>	Assigns <str> as the new value of variable.
   2462  *	  ::?=<str>	Assigns <str> as value of variable if
   2463  *			it was not already set.
   2464  *	  ::+=<str>	Appends <str> to variable.
   2465  *	  ::!=<cmd>	Assigns output of <cmd> as the new value of
   2466  *			variable.
   2467  */
   2468 
   2469 /* we now have some modifiers with long names */
   2470 #define STRMOD_MATCH(s, want, n) \
   2471     (strncmp(s, want, n) == 0 && (s[n] == endc || s[n] == ':'))
   2472 
   2473 static char *
   2474 ApplyModifiers(char *nstr, const char *tstr,
   2475 	       int startc, int endc,
   2476 	       Var *v, GNode *ctxt, Boolean errnum,
   2477 	       int *lengthPtr, void **freePtr)
   2478 {
   2479     const char 	   *start;
   2480     const char     *cp;    	/* Secondary pointer into str (place marker
   2481 				 * for tstr) */
   2482     char	   *newStr;	/* New value to return */
   2483     char	    termc;	/* Character which terminated scan */
   2484     int             cnt;	/* Used to count brace pairs when variable in
   2485 				 * in parens or braces */
   2486     char	delim;
   2487     int		modifier;	/* that we are processing */
   2488     Var_Parse_State parsestate; /* Flags passed to helper functions */
   2489 
   2490     delim = '\0';
   2491     parsestate.oneBigWord = FALSE;
   2492     parsestate.varSpace = ' ';	/* word separator */
   2493 
   2494     start = cp = tstr;
   2495 
   2496     while (*tstr && *tstr != endc) {
   2497 
   2498 	if (*tstr == '$') {
   2499 	    /*
   2500 	     * We have some complex modifiers in a variable.
   2501 	     */
   2502 	    void *freeIt;
   2503 	    char *rval;
   2504 	    int rlen;
   2505 
   2506 	    rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
   2507 
   2508 	    if (DEBUG(VAR)) {
   2509 		fprintf(debug_file, "Got '%s' from '%.*s'%.*s\n",
   2510 		       rval, rlen, tstr, rlen, tstr + rlen);
   2511 	    }
   2512 
   2513 	    tstr += rlen;
   2514 
   2515 	    if (rval != NULL && *rval) {
   2516 		int used;
   2517 
   2518 		nstr = ApplyModifiers(nstr, rval,
   2519 				      0, 0,
   2520 				      v, ctxt, errnum, &used, freePtr);
   2521 		if (nstr == var_Error
   2522 		    || (nstr == varNoError && errnum == 0)
   2523 		    || strlen(rval) != (size_t) used) {
   2524 		    if (freeIt)
   2525 			free(freeIt);
   2526 		    goto out;		/* error already reported */
   2527 		}
   2528 	    }
   2529 	    if (freeIt)
   2530 		free(freeIt);
   2531 	    if (*tstr == ':')
   2532 		tstr++;
   2533 	    else if (!*tstr && endc) {
   2534 		Error("Unclosed variable specification after complex modifier (expecting '%c') for %s", endc, v->name);
   2535 		goto out;
   2536 	    }
   2537 	    continue;
   2538 	}
   2539 	if (DEBUG(VAR)) {
   2540 	    fprintf(debug_file, "Applying :%c to \"%s\"\n", *tstr, nstr);
   2541 	}
   2542 	newStr = var_Error;
   2543 	switch ((modifier = *tstr)) {
   2544 	case ':':
   2545 	    {
   2546 		if (tstr[1] == '=' ||
   2547 		    (tstr[2] == '=' &&
   2548 		     (tstr[1] == '!' || tstr[1] == '+' || tstr[1] == '?'))) {
   2549 		    /*
   2550 		     * "::=", "::!=", "::+=", or "::?="
   2551 		     */
   2552 		    GNode *v_ctxt;		/* context where v belongs */
   2553 		    const char *emsg;
   2554 		    char *sv_name;
   2555 		    VarPattern	pattern;
   2556 		    int	how;
   2557 
   2558 		    if (v->name[0] == 0)
   2559 			goto bad_modifier;
   2560 
   2561 		    v_ctxt = ctxt;
   2562 		    sv_name = NULL;
   2563 		    ++tstr;
   2564 		    if (v->flags & VAR_JUNK) {
   2565 			/*
   2566 			 * We need to bmake_strdup() it incase
   2567 			 * VarGetPattern() recurses.
   2568 			 */
   2569 			sv_name = v->name;
   2570 			v->name = bmake_strdup(v->name);
   2571 		    } else if (ctxt != VAR_GLOBAL) {
   2572 			Var *gv = VarFind(v->name, ctxt, 0);
   2573 			if (gv == NULL)
   2574 			    v_ctxt = VAR_GLOBAL;
   2575 			else
   2576 			    VarFreeEnv(gv, TRUE);
   2577 		    }
   2578 
   2579 		    switch ((how = *tstr)) {
   2580 		    case '+':
   2581 		    case '?':
   2582 		    case '!':
   2583 			cp = &tstr[2];
   2584 			break;
   2585 		    default:
   2586 			cp = ++tstr;
   2587 			break;
   2588 		    }
   2589 		    delim = startc == PROPEN ? PRCLOSE : BRCLOSE;
   2590 		    pattern.flags = 0;
   2591 
   2592 		    pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   2593 						&cp, delim, NULL,
   2594 						&pattern.rightLen,
   2595 						NULL);
   2596 		    if (v->flags & VAR_JUNK) {
   2597 			/* restore original name */
   2598 			free(v->name);
   2599 			v->name = sv_name;
   2600 		    }
   2601 		    if (pattern.rhs == NULL)
   2602 			goto cleanup;
   2603 
   2604 		    termc = *--cp;
   2605 		    delim = '\0';
   2606 
   2607 		    switch (how) {
   2608 		    case '+':
   2609 			Var_Append(v->name, pattern.rhs, v_ctxt);
   2610 			break;
   2611 		    case '!':
   2612 			newStr = Cmd_Exec(pattern.rhs, &emsg);
   2613 			if (emsg)
   2614 			    Error(emsg, nstr);
   2615 			else
   2616 			    Var_Set(v->name, newStr,  v_ctxt, 0);
   2617 			if (newStr)
   2618 			    free(newStr);
   2619 			break;
   2620 		    case '?':
   2621 			if ((v->flags & VAR_JUNK) == 0)
   2622 			    break;
   2623 			/* FALLTHROUGH */
   2624 		    default:
   2625 			Var_Set(v->name, pattern.rhs, v_ctxt, 0);
   2626 			break;
   2627 		    }
   2628 		    free(UNCONST(pattern.rhs));
   2629 		    newStr = var_Error;
   2630 		    break;
   2631 		}
   2632 		goto default_case; /* "::<unrecognised>" */
   2633 	    }
   2634 	case '@':
   2635 	    {
   2636 		VarLoop_t	loop;
   2637 		int flags = VAR_NOSUBST;
   2638 
   2639 		cp = ++tstr;
   2640 		delim = '@';
   2641 		if ((loop.tvar = VarGetPattern(ctxt, &parsestate, errnum,
   2642 					       &cp, delim,
   2643 					       &flags, &loop.tvarLen,
   2644 					       NULL)) == NULL)
   2645 		    goto cleanup;
   2646 
   2647 		if ((loop.str = VarGetPattern(ctxt, &parsestate, errnum,
   2648 					      &cp, delim,
   2649 					      &flags, &loop.strLen,
   2650 					      NULL)) == NULL)
   2651 		    goto cleanup;
   2652 
   2653 		termc = *cp;
   2654 		delim = '\0';
   2655 
   2656 		loop.errnum = errnum;
   2657 		loop.ctxt = ctxt;
   2658 		newStr = VarModify(ctxt, &parsestate, nstr, VarLoopExpand,
   2659 				   &loop);
   2660 		free(loop.tvar);
   2661 		free(loop.str);
   2662 		break;
   2663 	    }
   2664 	case 'D':
   2665 	case 'U':
   2666 	    {
   2667 		Buffer  buf;    	/* Buffer for patterns */
   2668 		int	    wantit;	/* want data in buffer */
   2669 
   2670 		/*
   2671 		 * Pass through tstr looking for 1) escaped delimiters,
   2672 		 * '$'s and backslashes (place the escaped character in
   2673 		 * uninterpreted) and 2) unescaped $'s that aren't before
   2674 		 * the delimiter (expand the variable substitution).
   2675 		 * The result is left in the Buffer buf.
   2676 		 */
   2677 		Buf_Init(&buf, 0);
   2678 		for (cp = tstr + 1;
   2679 		     *cp != endc && *cp != ':' && *cp != '\0';
   2680 		     cp++) {
   2681 		    if ((*cp == '\\') &&
   2682 			((cp[1] == ':') ||
   2683 			 (cp[1] == '$') ||
   2684 			 (cp[1] == endc) ||
   2685 			 (cp[1] == '\\')))
   2686 			{
   2687 			    Buf_AddByte(&buf, cp[1]);
   2688 			    cp++;
   2689 			} else if (*cp == '$') {
   2690 			    /*
   2691 			     * If unescaped dollar sign, assume it's a
   2692 			     * variable substitution and recurse.
   2693 			     */
   2694 			    char    *cp2;
   2695 			    int	    len;
   2696 			    void    *freeIt;
   2697 
   2698 			    cp2 = Var_Parse(cp, ctxt, errnum, &len, &freeIt);
   2699 			    Buf_AddBytes(&buf, strlen(cp2), cp2);
   2700 			    if (freeIt)
   2701 				free(freeIt);
   2702 			    cp += len - 1;
   2703 			} else {
   2704 			    Buf_AddByte(&buf, *cp);
   2705 			}
   2706 		}
   2707 
   2708 		termc = *cp;
   2709 
   2710 		if (*tstr == 'U')
   2711 		    wantit = ((v->flags & VAR_JUNK) != 0);
   2712 		else
   2713 		    wantit = ((v->flags & VAR_JUNK) == 0);
   2714 		if ((v->flags & VAR_JUNK) != 0)
   2715 		    v->flags |= VAR_KEEP;
   2716 		if (wantit) {
   2717 		    newStr = Buf_Destroy(&buf, FALSE);
   2718 		} else {
   2719 		    newStr = nstr;
   2720 		    Buf_Destroy(&buf, TRUE);
   2721 		}
   2722 		break;
   2723 	    }
   2724 	case 'L':
   2725 	    {
   2726 		if ((v->flags & VAR_JUNK) != 0)
   2727 		    v->flags |= VAR_KEEP;
   2728 		newStr = bmake_strdup(v->name);
   2729 		cp = ++tstr;
   2730 		termc = *tstr;
   2731 		break;
   2732 	    }
   2733 	case 'P':
   2734 	    {
   2735 		GNode *gn;
   2736 
   2737 		if ((v->flags & VAR_JUNK) != 0)
   2738 		    v->flags |= VAR_KEEP;
   2739 		gn = Targ_FindNode(v->name, TARG_NOCREATE);
   2740 		if (gn == NULL || gn->type & OP_NOPATH) {
   2741 		    newStr = NULL;
   2742 		} else if (gn->path) {
   2743 		    newStr = bmake_strdup(gn->path);
   2744 		} else {
   2745 		    newStr = Dir_FindFile(v->name, Suff_FindPath(gn));
   2746 		}
   2747 		if (!newStr) {
   2748 		    newStr = bmake_strdup(v->name);
   2749 		}
   2750 		cp = ++tstr;
   2751 		termc = *tstr;
   2752 		break;
   2753 	    }
   2754 	case '!':
   2755 	    {
   2756 		const char *emsg;
   2757 		VarPattern 	    pattern;
   2758 		pattern.flags = 0;
   2759 
   2760 		delim = '!';
   2761 
   2762 		cp = ++tstr;
   2763 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   2764 						 &cp, delim,
   2765 						 NULL, &pattern.rightLen,
   2766 						 NULL)) == NULL)
   2767 		    goto cleanup;
   2768 		newStr = Cmd_Exec(pattern.rhs, &emsg);
   2769 		free(UNCONST(pattern.rhs));
   2770 		if (emsg)
   2771 		    Error(emsg, nstr);
   2772 		termc = *cp;
   2773 		delim = '\0';
   2774 		if (v->flags & VAR_JUNK) {
   2775 		    v->flags |= VAR_KEEP;
   2776 		}
   2777 		break;
   2778 	    }
   2779 	case '[':
   2780 	    {
   2781 		/*
   2782 		 * Look for the closing ']', recursively
   2783 		 * expanding any embedded variables.
   2784 		 *
   2785 		 * estr is a pointer to the expanded result,
   2786 		 * which we must free().
   2787 		 */
   2788 		char *estr;
   2789 
   2790 		cp = tstr+1; /* point to char after '[' */
   2791 		delim = ']'; /* look for closing ']' */
   2792 		estr = VarGetPattern(ctxt, &parsestate,
   2793 				     errnum, &cp, delim,
   2794 				     NULL, NULL, NULL);
   2795 		if (estr == NULL)
   2796 		    goto cleanup; /* report missing ']' */
   2797 		/* now cp points just after the closing ']' */
   2798 		delim = '\0';
   2799 		if (cp[0] != ':' && cp[0] != endc) {
   2800 		    /* Found junk after ']' */
   2801 		    free(estr);
   2802 		    goto bad_modifier;
   2803 		}
   2804 		if (estr[0] == '\0') {
   2805 		    /* Found empty square brackets in ":[]". */
   2806 		    free(estr);
   2807 		    goto bad_modifier;
   2808 		} else if (estr[0] == '#' && estr[1] == '\0') {
   2809 		    /* Found ":[#]" */
   2810 
   2811 		    /*
   2812 		     * We will need enough space for the decimal
   2813 		     * representation of an int.  We calculate the
   2814 		     * space needed for the octal representation,
   2815 		     * and add enough slop to cope with a '-' sign
   2816 		     * (which should never be needed) and a '\0'
   2817 		     * string terminator.
   2818 		     */
   2819 		    int newStrSize =
   2820 			(sizeof(int) * CHAR_BIT + 2) / 3 + 2;
   2821 
   2822 		    newStr = bmake_malloc(newStrSize);
   2823 		    if (parsestate.oneBigWord) {
   2824 			strncpy(newStr, "1", newStrSize);
   2825 		    } else {
   2826 			/* XXX: brk_string() is a rather expensive
   2827 			 * way of counting words. */
   2828 			char **av;
   2829 			char *as;
   2830 			int ac;
   2831 
   2832 			av = brk_string(nstr, &ac, FALSE, &as);
   2833 			snprintf(newStr, newStrSize,  "%d", ac);
   2834 			free(as);
   2835 			free(av);
   2836 		    }
   2837 		    termc = *cp;
   2838 		    free(estr);
   2839 		    break;
   2840 		} else if (estr[0] == '*' && estr[1] == '\0') {
   2841 		    /* Found ":[*]" */
   2842 		    parsestate.oneBigWord = TRUE;
   2843 		    newStr = nstr;
   2844 		    termc = *cp;
   2845 		    free(estr);
   2846 		    break;
   2847 		} else if (estr[0] == '@' && estr[1] == '\0') {
   2848 		    /* Found ":[@]" */
   2849 		    parsestate.oneBigWord = FALSE;
   2850 		    newStr = nstr;
   2851 		    termc = *cp;
   2852 		    free(estr);
   2853 		    break;
   2854 		} else {
   2855 		    /*
   2856 		     * We expect estr to contain a single
   2857 		     * integer for :[N], or two integers
   2858 		     * separated by ".." for :[start..end].
   2859 		     */
   2860 		    char *ep;
   2861 
   2862 		    VarSelectWords_t seldata = { 0, 0 };
   2863 
   2864 		    seldata.start = strtol(estr, &ep, 0);
   2865 		    if (ep == estr) {
   2866 			/* Found junk instead of a number */
   2867 			free(estr);
   2868 			goto bad_modifier;
   2869 		    } else if (ep[0] == '\0') {
   2870 			/* Found only one integer in :[N] */
   2871 			seldata.end = seldata.start;
   2872 		    } else if (ep[0] == '.' && ep[1] == '.' &&
   2873 			       ep[2] != '\0') {
   2874 			/* Expecting another integer after ".." */
   2875 			ep += 2;
   2876 			seldata.end = strtol(ep, &ep, 0);
   2877 			if (ep[0] != '\0') {
   2878 			    /* Found junk after ".." */
   2879 			    free(estr);
   2880 			    goto bad_modifier;
   2881 			}
   2882 		    } else {
   2883 			/* Found junk instead of ".." */
   2884 			free(estr);
   2885 			goto bad_modifier;
   2886 		    }
   2887 		    /*
   2888 		     * Now seldata is properly filled in,
   2889 		     * but we still have to check for 0 as
   2890 		     * a special case.
   2891 		     */
   2892 		    if (seldata.start == 0 && seldata.end == 0) {
   2893 			/* ":[0]" or perhaps ":[0..0]" */
   2894 			parsestate.oneBigWord = TRUE;
   2895 			newStr = nstr;
   2896 			termc = *cp;
   2897 			free(estr);
   2898 			break;
   2899 		    } else if (seldata.start == 0 ||
   2900 			       seldata.end == 0) {
   2901 			/* ":[0..N]" or ":[N..0]" */
   2902 			free(estr);
   2903 			goto bad_modifier;
   2904 		    }
   2905 		    /*
   2906 		     * Normal case: select the words
   2907 		     * described by seldata.
   2908 		     */
   2909 		    newStr = VarSelectWords(ctxt, &parsestate,
   2910 					    nstr, &seldata);
   2911 
   2912 		    termc = *cp;
   2913 		    free(estr);
   2914 		    break;
   2915 		}
   2916 
   2917 	    }
   2918 	case 'g':
   2919 	    cp = tstr + 1;	/* make sure it is set */
   2920 	    if (STRMOD_MATCH(tstr, "gmtime", 6)) {
   2921 		newStr = VarStrftime(nstr, 1);
   2922 		cp = tstr + 6;
   2923 		termc = *cp;
   2924 	    } else {
   2925 		goto default_case;
   2926 	    }
   2927 	    break;
   2928 	case 'h':
   2929 	    cp = tstr + 1;	/* make sure it is set */
   2930 	    if (STRMOD_MATCH(tstr, "hash", 4)) {
   2931 		newStr = VarHash(nstr);
   2932 		cp = tstr + 4;
   2933 		termc = *cp;
   2934 	    } else {
   2935 		goto default_case;
   2936 	    }
   2937 	    break;
   2938 	case 'l':
   2939 	    cp = tstr + 1;	/* make sure it is set */
   2940 	    if (STRMOD_MATCH(tstr, "localtime", 9)) {
   2941 		newStr = VarStrftime(nstr, 0);
   2942 		cp = tstr + 9;
   2943 		termc = *cp;
   2944 	    } else {
   2945 		goto default_case;
   2946 	    }
   2947 	    break;
   2948 	case 't':
   2949 	    {
   2950 		cp = tstr + 1;	/* make sure it is set */
   2951 		if (tstr[1] != endc && tstr[1] != ':') {
   2952 		    if (tstr[1] == 's') {
   2953 			/*
   2954 			 * Use the char (if any) at tstr[2]
   2955 			 * as the word separator.
   2956 			 */
   2957 			VarPattern pattern;
   2958 
   2959 			if (tstr[2] != endc &&
   2960 			    (tstr[3] == endc || tstr[3] == ':')) {
   2961 			    /* ":ts<unrecognised><endc>" or
   2962 			     * ":ts<unrecognised>:" */
   2963 			    parsestate.varSpace = tstr[2];
   2964 			    cp = tstr + 3;
   2965 			} else if (tstr[2] == endc || tstr[2] == ':') {
   2966 			    /* ":ts<endc>" or ":ts:" */
   2967 			    parsestate.varSpace = 0; /* no separator */
   2968 			    cp = tstr + 2;
   2969 			} else if (tstr[2] == '\\') {
   2970 			    switch (tstr[3]) {
   2971 			    case 'n':
   2972 				parsestate.varSpace = '\n';
   2973 				cp = tstr + 4;
   2974 				break;
   2975 			    case 't':
   2976 				parsestate.varSpace = '\t';
   2977 				cp = tstr + 4;
   2978 				break;
   2979 			    default:
   2980 				if (isdigit((unsigned char)tstr[3])) {
   2981 				    char *ep;
   2982 
   2983 				    parsestate.varSpace =
   2984 					strtoul(&tstr[3], &ep, 0);
   2985 				    if (*ep != ':' && *ep != endc)
   2986 					goto bad_modifier;
   2987 				    cp = ep;
   2988 				} else {
   2989 				    /*
   2990 				     * ":ts<backslash><unrecognised>".
   2991 				     */
   2992 				    goto bad_modifier;
   2993 				}
   2994 				break;
   2995 			    }
   2996 			} else {
   2997 			    /*
   2998 			     * Found ":ts<unrecognised><unrecognised>".
   2999 			     */
   3000 			    goto bad_modifier;
   3001 			}
   3002 
   3003 			termc = *cp;
   3004 
   3005 			/*
   3006 			 * We cannot be certain that VarModify
   3007 			 * will be used - even if there is a
   3008 			 * subsequent modifier, so do a no-op
   3009 			 * VarSubstitute now to for str to be
   3010 			 * re-expanded without the spaces.
   3011 			 */
   3012 			pattern.flags = VAR_SUB_ONE;
   3013 			pattern.lhs = pattern.rhs = "\032";
   3014 			pattern.leftLen = pattern.rightLen = 1;
   3015 
   3016 			newStr = VarModify(ctxt, &parsestate, nstr,
   3017 					   VarSubstitute,
   3018 					   &pattern);
   3019 		    } else if (tstr[2] == endc || tstr[2] == ':') {
   3020 			/*
   3021 			 * Check for two-character options:
   3022 			 * ":tu", ":tl"
   3023 			 */
   3024 			if (tstr[1] == 'A') { /* absolute path */
   3025 			    newStr = VarModify(ctxt, &parsestate, nstr,
   3026 					       VarRealpath, NULL);
   3027 			    cp = tstr + 2;
   3028 			    termc = *cp;
   3029 			} else if (tstr[1] == 'u' || tstr[1] == 'l') {
   3030 			    newStr = VarChangeCase(nstr, (tstr[1] == 'u'));
   3031 			    cp = tstr + 2;
   3032 			    termc = *cp;
   3033 			} else if (tstr[1] == 'W' || tstr[1] == 'w') {
   3034 			    parsestate.oneBigWord = (tstr[1] == 'W');
   3035 			    newStr = nstr;
   3036 			    cp = tstr + 2;
   3037 			    termc = *cp;
   3038 			} else {
   3039 			    /* Found ":t<unrecognised>:" or
   3040 			     * ":t<unrecognised><endc>". */
   3041 			    goto bad_modifier;
   3042 			}
   3043 		    } else {
   3044 			/*
   3045 			 * Found ":t<unrecognised><unrecognised>".
   3046 			 */
   3047 			goto bad_modifier;
   3048 		    }
   3049 		} else {
   3050 		    /*
   3051 		     * Found ":t<endc>" or ":t:".
   3052 		     */
   3053 		    goto bad_modifier;
   3054 		}
   3055 		break;
   3056 	    }
   3057 	case 'N':
   3058 	case 'M':
   3059 	    {
   3060 		char    *pattern;
   3061 		const char *endpat; /* points just after end of pattern */
   3062 		char    *cp2;
   3063 		Boolean copy;	/* pattern should be, or has been, copied */
   3064 		Boolean needSubst;
   3065 		int nest;
   3066 
   3067 		copy = FALSE;
   3068 		needSubst = FALSE;
   3069 		nest = 1;
   3070 		/*
   3071 		 * In the loop below, ignore ':' unless we are at
   3072 		 * (or back to) the original brace level.
   3073 		 * XXX This will likely not work right if $() and ${}
   3074 		 * are intermixed.
   3075 		 */
   3076 		for (cp = tstr + 1;
   3077 		     *cp != '\0' && !(*cp == ':' && nest == 1);
   3078 		     cp++)
   3079 		    {
   3080 			if (*cp == '\\' &&
   3081 			    (cp[1] == ':' ||
   3082 			     cp[1] == endc || cp[1] == startc)) {
   3083 			    if (!needSubst) {
   3084 				copy = TRUE;
   3085 			    }
   3086 			    cp++;
   3087 			    continue;
   3088 			}
   3089 			if (*cp == '$') {
   3090 			    needSubst = TRUE;
   3091 			}
   3092 			if (*cp == '(' || *cp == '{')
   3093 			    ++nest;
   3094 			if (*cp == ')' || *cp == '}') {
   3095 			    --nest;
   3096 			    if (nest == 0)
   3097 				break;
   3098 			}
   3099 		    }
   3100 		termc = *cp;
   3101 		endpat = cp;
   3102 		if (copy) {
   3103 		    /*
   3104 		     * Need to compress the \:'s out of the pattern, so
   3105 		     * allocate enough room to hold the uncompressed
   3106 		     * pattern (note that cp started at tstr+1, so
   3107 		     * cp - tstr takes the null byte into account) and
   3108 		     * compress the pattern into the space.
   3109 		     */
   3110 		    pattern = bmake_malloc(cp - tstr);
   3111 		    for (cp2 = pattern, cp = tstr + 1;
   3112 			 cp < endpat;
   3113 			 cp++, cp2++)
   3114 			{
   3115 			    if ((*cp == '\\') && (cp+1 < endpat) &&
   3116 				(cp[1] == ':' || cp[1] == endc)) {
   3117 				cp++;
   3118 			    }
   3119 			    *cp2 = *cp;
   3120 			}
   3121 		    *cp2 = '\0';
   3122 		    endpat = cp2;
   3123 		} else {
   3124 		    /*
   3125 		     * Either Var_Subst or VarModify will need a
   3126 		     * nul-terminated string soon, so construct one now.
   3127 		     */
   3128 		    pattern = bmake_strndup(tstr+1, endpat - (tstr + 1));
   3129 		}
   3130 		if (needSubst) {
   3131 		    /*
   3132 		     * pattern contains embedded '$', so use Var_Subst to
   3133 		     * expand it.
   3134 		     */
   3135 		    cp2 = pattern;
   3136 		    pattern = Var_Subst(NULL, cp2, ctxt, errnum);
   3137 		    free(cp2);
   3138 		}
   3139 		if (DEBUG(VAR))
   3140 		    fprintf(debug_file, "Pattern for [%s] is [%s]\n", nstr,
   3141 			pattern);
   3142 		if (*tstr == 'M') {
   3143 		    newStr = VarModify(ctxt, &parsestate, nstr, VarMatch,
   3144 				       pattern);
   3145 		} else {
   3146 		    newStr = VarModify(ctxt, &parsestate, nstr, VarNoMatch,
   3147 				       pattern);
   3148 		}
   3149 		free(pattern);
   3150 		break;
   3151 	    }
   3152 	case 'S':
   3153 	    {
   3154 		VarPattern 	    pattern;
   3155 		Var_Parse_State tmpparsestate;
   3156 
   3157 		pattern.flags = 0;
   3158 		tmpparsestate = parsestate;
   3159 		delim = tstr[1];
   3160 		tstr += 2;
   3161 
   3162 		/*
   3163 		 * If pattern begins with '^', it is anchored to the
   3164 		 * start of the word -- skip over it and flag pattern.
   3165 		 */
   3166 		if (*tstr == '^') {
   3167 		    pattern.flags |= VAR_MATCH_START;
   3168 		    tstr += 1;
   3169 		}
   3170 
   3171 		cp = tstr;
   3172 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
   3173 						 &cp, delim,
   3174 						 &pattern.flags,
   3175 						 &pattern.leftLen,
   3176 						 NULL)) == NULL)
   3177 		    goto cleanup;
   3178 
   3179 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   3180 						 &cp, delim, NULL,
   3181 						 &pattern.rightLen,
   3182 						 &pattern)) == NULL)
   3183 		    goto cleanup;
   3184 
   3185 		/*
   3186 		 * Check for global substitution. If 'g' after the final
   3187 		 * delimiter, substitution is global and is marked that
   3188 		 * way.
   3189 		 */
   3190 		for (;; cp++) {
   3191 		    switch (*cp) {
   3192 		    case 'g':
   3193 			pattern.flags |= VAR_SUB_GLOBAL;
   3194 			continue;
   3195 		    case '1':
   3196 			pattern.flags |= VAR_SUB_ONE;
   3197 			continue;
   3198 		    case 'W':
   3199 			tmpparsestate.oneBigWord = TRUE;
   3200 			continue;
   3201 		    }
   3202 		    break;
   3203 		}
   3204 
   3205 		termc = *cp;
   3206 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
   3207 				   VarSubstitute,
   3208 				   &pattern);
   3209 
   3210 		/*
   3211 		 * Free the two strings.
   3212 		 */
   3213 		free(UNCONST(pattern.lhs));
   3214 		free(UNCONST(pattern.rhs));
   3215 		delim = '\0';
   3216 		break;
   3217 	    }
   3218 	case '?':
   3219 	    {
   3220 		VarPattern 	pattern;
   3221 		Boolean	value;
   3222 
   3223 		/* find ':', and then substitute accordingly */
   3224 
   3225 		pattern.flags = 0;
   3226 
   3227 		cp = ++tstr;
   3228 		delim = ':';
   3229 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate, errnum,
   3230 						 &cp, delim, NULL,
   3231 						 &pattern.leftLen,
   3232 						 NULL)) == NULL)
   3233 		    goto cleanup;
   3234 
   3235 		/* BROPEN or PROPEN */
   3236 		delim = endc;
   3237 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate, errnum,
   3238 						 &cp, delim, NULL,
   3239 						 &pattern.rightLen,
   3240 						 NULL)) == NULL)
   3241 		    goto cleanup;
   3242 
   3243 		termc = *--cp;
   3244 		delim = '\0';
   3245 		if (Cond_EvalExpression(NULL, v->name, &value, 0)
   3246 		    == COND_INVALID) {
   3247 		    Error("Bad conditional expression `%s' in %s?%s:%s",
   3248 			  v->name, v->name, pattern.lhs, pattern.rhs);
   3249 		    goto cleanup;
   3250 		}
   3251 
   3252 		if (value) {
   3253 		    newStr = UNCONST(pattern.lhs);
   3254 		    free(UNCONST(pattern.rhs));
   3255 		} else {
   3256 		    newStr = UNCONST(pattern.rhs);
   3257 		    free(UNCONST(pattern.lhs));
   3258 		}
   3259 		if (v->flags & VAR_JUNK) {
   3260 		    v->flags |= VAR_KEEP;
   3261 		}
   3262 		break;
   3263 	    }
   3264 #ifndef NO_REGEX
   3265 	case 'C':
   3266 	    {
   3267 		VarREPattern    pattern;
   3268 		char           *re;
   3269 		int             error;
   3270 		Var_Parse_State tmpparsestate;
   3271 
   3272 		pattern.flags = 0;
   3273 		tmpparsestate = parsestate;
   3274 		delim = tstr[1];
   3275 		tstr += 2;
   3276 
   3277 		cp = tstr;
   3278 
   3279 		if ((re = VarGetPattern(ctxt, &parsestate, errnum, &cp, delim,
   3280 					NULL, NULL, NULL)) == NULL)
   3281 		    goto cleanup;
   3282 
   3283 		if ((pattern.replace = VarGetPattern(ctxt, &parsestate,
   3284 						     errnum, &cp, delim, NULL,
   3285 						     NULL, NULL)) == NULL){
   3286 		    free(re);
   3287 		    goto cleanup;
   3288 		}
   3289 
   3290 		for (;; cp++) {
   3291 		    switch (*cp) {
   3292 		    case 'g':
   3293 			pattern.flags |= VAR_SUB_GLOBAL;
   3294 			continue;
   3295 		    case '1':
   3296 			pattern.flags |= VAR_SUB_ONE;
   3297 			continue;
   3298 		    case 'W':
   3299 			tmpparsestate.oneBigWord = TRUE;
   3300 			continue;
   3301 		    }
   3302 		    break;
   3303 		}
   3304 
   3305 		termc = *cp;
   3306 
   3307 		error = regcomp(&pattern.re, re, REG_EXTENDED);
   3308 		free(re);
   3309 		if (error)  {
   3310 		    *lengthPtr = cp - start + 1;
   3311 		    VarREError(error, &pattern.re, "RE substitution error");
   3312 		    free(pattern.replace);
   3313 		    goto cleanup;
   3314 		}
   3315 
   3316 		pattern.nsub = pattern.re.re_nsub + 1;
   3317 		if (pattern.nsub < 1)
   3318 		    pattern.nsub = 1;
   3319 		if (pattern.nsub > 10)
   3320 		    pattern.nsub = 10;
   3321 		pattern.matches = bmake_malloc(pattern.nsub *
   3322 					  sizeof(regmatch_t));
   3323 		newStr = VarModify(ctxt, &tmpparsestate, nstr,
   3324 				   VarRESubstitute,
   3325 				   &pattern);
   3326 		regfree(&pattern.re);
   3327 		free(pattern.replace);
   3328 		free(pattern.matches);
   3329 		delim = '\0';
   3330 		break;
   3331 	    }
   3332 #endif
   3333 	case 'Q':
   3334 	    if (tstr[1] == endc || tstr[1] == ':') {
   3335 		newStr = VarQuote(nstr);
   3336 		cp = tstr + 1;
   3337 		termc = *cp;
   3338 		break;
   3339 	    }
   3340 	    goto default_case;
   3341 	case 'T':
   3342 	    if (tstr[1] == endc || tstr[1] == ':') {
   3343 		newStr = VarModify(ctxt, &parsestate, nstr, VarTail,
   3344 				   NULL);
   3345 		cp = tstr + 1;
   3346 		termc = *cp;
   3347 		break;
   3348 	    }
   3349 	    goto default_case;
   3350 	case 'H':
   3351 	    if (tstr[1] == endc || tstr[1] == ':') {
   3352 		newStr = VarModify(ctxt, &parsestate, nstr, VarHead,
   3353 				   NULL);
   3354 		cp = tstr + 1;
   3355 		termc = *cp;
   3356 		break;
   3357 	    }
   3358 	    goto default_case;
   3359 	case 'E':
   3360 	    if (tstr[1] == endc || tstr[1] == ':') {
   3361 		newStr = VarModify(ctxt, &parsestate, nstr, VarSuffix,
   3362 				   NULL);
   3363 		cp = tstr + 1;
   3364 		termc = *cp;
   3365 		break;
   3366 	    }
   3367 	    goto default_case;
   3368 	case 'R':
   3369 	    if (tstr[1] == endc || tstr[1] == ':') {
   3370 		newStr = VarModify(ctxt, &parsestate, nstr, VarRoot,
   3371 				   NULL);
   3372 		cp = tstr + 1;
   3373 		termc = *cp;
   3374 		break;
   3375 	    }
   3376 	    goto default_case;
   3377 	case 'O':
   3378 	    {
   3379 		char otype;
   3380 
   3381 		cp = tstr + 1;	/* skip to the rest in any case */
   3382 		if (tstr[1] == endc || tstr[1] == ':') {
   3383 		    otype = 's';
   3384 		    termc = *cp;
   3385 		} else if ( (tstr[1] == 'x') &&
   3386 			    (tstr[2] == endc || tstr[2] == ':') ) {
   3387 		    otype = tstr[1];
   3388 		    cp = tstr + 2;
   3389 		    termc = *cp;
   3390 		} else {
   3391 		    goto bad_modifier;
   3392 		}
   3393 		newStr = VarOrder(nstr, otype);
   3394 		break;
   3395 	    }
   3396 	case 'u':
   3397 	    if (tstr[1] == endc || tstr[1] == ':') {
   3398 		newStr = VarUniq(nstr);
   3399 		cp = tstr + 1;
   3400 		termc = *cp;
   3401 		break;
   3402 	    }
   3403 	    goto default_case;
   3404 #ifdef SUNSHCMD
   3405 	case 's':
   3406 	    if (tstr[1] == 'h' && (tstr[2] == endc || tstr[2] == ':')) {
   3407 		const char *emsg;
   3408 		newStr = Cmd_Exec(nstr, &emsg);
   3409 		if (emsg)
   3410 		    Error(emsg, nstr);
   3411 		cp = tstr + 2;
   3412 		termc = *cp;
   3413 		break;
   3414 	    }
   3415 	    goto default_case;
   3416 #endif
   3417 	default:
   3418 	default_case:
   3419 	{
   3420 #ifdef SYSVVARSUB
   3421 	    /*
   3422 	     * This can either be a bogus modifier or a System-V
   3423 	     * substitution command.
   3424 	     */
   3425 	    VarPattern      pattern;
   3426 	    Boolean         eqFound;
   3427 
   3428 	    pattern.flags = 0;
   3429 	    eqFound = FALSE;
   3430 	    /*
   3431 	     * First we make a pass through the string trying
   3432 	     * to verify it is a SYSV-make-style translation:
   3433 	     * it must be: <string1>=<string2>)
   3434 	     */
   3435 	    cp = tstr;
   3436 	    cnt = 1;
   3437 	    while (*cp != '\0' && cnt) {
   3438 		if (*cp == '=') {
   3439 		    eqFound = TRUE;
   3440 		    /* continue looking for endc */
   3441 		}
   3442 		else if (*cp == endc)
   3443 		    cnt--;
   3444 		else if (*cp == startc)
   3445 		    cnt++;
   3446 		if (cnt)
   3447 		    cp++;
   3448 	    }
   3449 	    if (*cp == endc && eqFound) {
   3450 
   3451 		/*
   3452 		 * Now we break this sucker into the lhs and
   3453 		 * rhs. We must null terminate them of course.
   3454 		 */
   3455 		delim='=';
   3456 		cp = tstr;
   3457 		if ((pattern.lhs = VarGetPattern(ctxt, &parsestate,
   3458 						 errnum, &cp, delim, &pattern.flags,
   3459 						 &pattern.leftLen, NULL)) == NULL)
   3460 		    goto cleanup;
   3461 		delim = endc;
   3462 		if ((pattern.rhs = VarGetPattern(ctxt, &parsestate,
   3463 						 errnum, &cp, delim, NULL, &pattern.rightLen,
   3464 						 &pattern)) == NULL)
   3465 		    goto cleanup;
   3466 
   3467 		/*
   3468 		 * SYSV modifications happen through the whole
   3469 		 * string. Note the pattern is anchored at the end.
   3470 		 */
   3471 		termc = *--cp;
   3472 		delim = '\0';
   3473 		if (pattern.leftLen == 0 && *nstr == '\0') {
   3474 		    newStr = nstr;	/* special case */
   3475 		} else {
   3476 		    newStr = VarModify(ctxt, &parsestate, nstr,
   3477 				       VarSYSVMatch,
   3478 				       &pattern);
   3479 		}
   3480 		free(UNCONST(pattern.lhs));
   3481 		free(UNCONST(pattern.rhs));
   3482 	    } else
   3483 #endif
   3484 		{
   3485 		    Error("Unknown modifier '%c'", *tstr);
   3486 		    for (cp = tstr+1;
   3487 			 *cp != ':' && *cp != endc && *cp != '\0';
   3488 			 cp++)
   3489 			continue;
   3490 		    termc = *cp;
   3491 		    newStr = var_Error;
   3492 		}
   3493 	    }
   3494 	}
   3495 	if (DEBUG(VAR)) {
   3496 	    fprintf(debug_file, "Result of :%c is \"%s\"\n", modifier, newStr);
   3497 	}
   3498 
   3499 	if (newStr != nstr) {
   3500 	    if (*freePtr) {
   3501 		free(nstr);
   3502 		*freePtr = NULL;
   3503 	    }
   3504 	    nstr = newStr;
   3505 	    if (nstr != var_Error && nstr != varNoError) {
   3506 		*freePtr = nstr;
   3507 	    }
   3508 	}
   3509 	if (termc == '\0' && endc != '\0') {
   3510 	    Error("Unclosed variable specification (expecting '%c') for \"%s\" (value \"%s\") modifier %c", endc, v->name, nstr, modifier);
   3511 	} else if (termc == ':') {
   3512 	    cp++;
   3513 	}
   3514 	tstr = cp;
   3515     }
   3516  out:
   3517     *lengthPtr = tstr - start;
   3518     return (nstr);
   3519 
   3520  bad_modifier:
   3521     /* "{(" */
   3522     Error("Bad modifier `:%.*s' for %s", (int)strcspn(tstr, ":)}"), tstr,
   3523 	  v->name);
   3524 
   3525  cleanup:
   3526     *lengthPtr = cp - start;
   3527     if (delim != '\0')
   3528 	Error("Unclosed substitution for %s (%c missing)",
   3529 	      v->name, delim);
   3530     if (*freePtr) {
   3531 	free(*freePtr);
   3532 	*freePtr = NULL;
   3533     }
   3534     return (var_Error);
   3535 }
   3536 
   3537 /*-
   3538  *-----------------------------------------------------------------------
   3539  * Var_Parse --
   3540  *	Given the start of a variable invocation, extract the variable
   3541  *	name and find its value, then modify it according to the
   3542  *	specification.
   3543  *
   3544  * Input:
   3545  *	str		The string to parse
   3546  *	ctxt		The context for the variable
   3547  *	errnum		TRUE if undefined variables are an error
   3548  *	lengthPtr	OUT: The length of the specification
   3549  *	freePtr		OUT: Non-NULL if caller should free *freePtr
   3550  *
   3551  * Results:
   3552  *	The (possibly-modified) value of the variable or var_Error if the
   3553  *	specification is invalid. The length of the specification is
   3554  *	placed in *lengthPtr (for invalid specifications, this is just
   3555  *	2...?).
   3556  *	If *freePtr is non-NULL then it's a pointer that the caller
   3557  *	should pass to free() to free memory used by the result.
   3558  *
   3559  * Side Effects:
   3560  *	None.
   3561  *
   3562  *-----------------------------------------------------------------------
   3563  */
   3564 /* coverity[+alloc : arg-*4] */
   3565 char *
   3566 Var_Parse(const char *str, GNode *ctxt, Boolean errnum, int *lengthPtr,
   3567 	  void **freePtr)
   3568 {
   3569     const char	   *tstr;    	/* Pointer into str */
   3570     Var		   *v;		/* Variable in invocation */
   3571     Boolean 	    haveModifier;/* TRUE if have modifiers for the variable */
   3572     char	    endc;    	/* Ending character when variable in parens
   3573 				 * or braces */
   3574     char	    startc;	/* Starting character when variable in parens
   3575 				 * or braces */
   3576     int		    vlen;	/* Length of variable name */
   3577     const char 	   *start;	/* Points to original start of str */
   3578     char	   *nstr;	/* New string, used during expansion */
   3579     Boolean 	    dynamic;	/* TRUE if the variable is local and we're
   3580 				 * expanding it in a non-local context. This
   3581 				 * is done to support dynamic sources. The
   3582 				 * result is just the invocation, unaltered */
   3583     Var_Parse_State parsestate; /* Flags passed to helper functions */
   3584     char	  name[2];
   3585 
   3586     *freePtr = NULL;
   3587     dynamic = FALSE;
   3588     start = str;
   3589     parsestate.oneBigWord = FALSE;
   3590     parsestate.varSpace = ' ';	/* word separator */
   3591 
   3592     startc = str[1];
   3593     if (startc != PROPEN && startc != BROPEN) {
   3594 	/*
   3595 	 * If it's not bounded by braces of some sort, life is much simpler.
   3596 	 * We just need to check for the first character and return the
   3597 	 * value if it exists.
   3598 	 */
   3599 
   3600 	/* Error out some really stupid names */
   3601 	if (startc == '\0' || strchr(")}:$", startc)) {
   3602 	    *lengthPtr = 1;
   3603 	    return var_Error;
   3604 	}
   3605 	name[0] = startc;
   3606 	name[1] = '\0';
   3607 
   3608 	v = VarFind(name, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   3609 	if (v == NULL) {
   3610 	    *lengthPtr = 2;
   3611 
   3612 	    if ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)) {
   3613 		/*
   3614 		 * If substituting a local variable in a non-local context,
   3615 		 * assume it's for dynamic source stuff. We have to handle
   3616 		 * this specially and return the longhand for the variable
   3617 		 * with the dollar sign escaped so it makes it back to the
   3618 		 * caller. Only four of the local variables are treated
   3619 		 * specially as they are the only four that will be set
   3620 		 * when dynamic sources are expanded.
   3621 		 */
   3622 		switch (str[1]) {
   3623 		    case '@':
   3624 			return UNCONST("$(.TARGET)");
   3625 		    case '%':
   3626 			return UNCONST("$(.ARCHIVE)");
   3627 		    case '*':
   3628 			return UNCONST("$(.PREFIX)");
   3629 		    case '!':
   3630 			return UNCONST("$(.MEMBER)");
   3631 		}
   3632 	    }
   3633 	    /*
   3634 	     * Error
   3635 	     */
   3636 	    return (errnum ? var_Error : varNoError);
   3637 	} else {
   3638 	    haveModifier = FALSE;
   3639 	    tstr = &str[1];
   3640 	    endc = str[1];
   3641 	}
   3642     } else {
   3643 	Buffer buf;	/* Holds the variable name */
   3644 
   3645 	endc = startc == PROPEN ? PRCLOSE : BRCLOSE;
   3646 	Buf_Init(&buf, 0);
   3647 
   3648 	/*
   3649 	 * Skip to the end character or a colon, whichever comes first.
   3650 	 */
   3651 	for (tstr = str + 2;
   3652 	     *tstr != '\0' && *tstr != endc && *tstr != ':';
   3653 	     tstr++)
   3654 	{
   3655 	    /*
   3656 	     * A variable inside a variable, expand
   3657 	     */
   3658 	    if (*tstr == '$') {
   3659 		int rlen;
   3660 		void *freeIt;
   3661 		char *rval = Var_Parse(tstr, ctxt, errnum, &rlen, &freeIt);
   3662 		if (rval != NULL) {
   3663 		    Buf_AddBytes(&buf, strlen(rval), rval);
   3664 		}
   3665 		if (freeIt)
   3666 		    free(freeIt);
   3667 		tstr += rlen - 1;
   3668 	    }
   3669 	    else
   3670 		Buf_AddByte(&buf, *tstr);
   3671 	}
   3672 	if (*tstr == ':') {
   3673 	    haveModifier = TRUE;
   3674 	} else if (*tstr != '\0') {
   3675 	    haveModifier = FALSE;
   3676 	} else {
   3677 	    /*
   3678 	     * If we never did find the end character, return NULL
   3679 	     * right now, setting the length to be the distance to
   3680 	     * the end of the string, since that's what make does.
   3681 	     */
   3682 	    *lengthPtr = tstr - str;
   3683 	    Buf_Destroy(&buf, TRUE);
   3684 	    return (var_Error);
   3685 	}
   3686 	str = Buf_GetAll(&buf, &vlen);
   3687 
   3688 	/*
   3689 	 * At this point, str points into newly allocated memory from
   3690 	 * buf, containing only the name of the variable.
   3691 	 *
   3692 	 * start and tstr point into the const string that was pointed
   3693 	 * to by the original value of the str parameter.  start points
   3694 	 * to the '$' at the beginning of the string, while tstr points
   3695 	 * to the char just after the end of the variable name -- this
   3696 	 * will be '\0', ':', PRCLOSE, or BRCLOSE.
   3697 	 */
   3698 
   3699 	v = VarFind(str, ctxt, FIND_ENV | FIND_GLOBAL | FIND_CMD);
   3700 	/*
   3701 	 * Check also for bogus D and F forms of local variables since we're
   3702 	 * in a local context and the name is the right length.
   3703 	 */
   3704 	if ((v == NULL) && (ctxt != VAR_CMD) && (ctxt != VAR_GLOBAL) &&
   3705 		(vlen == 2) && (str[1] == 'F' || str[1] == 'D') &&
   3706 		strchr("@%*!<>", str[0]) != NULL) {
   3707 	    /*
   3708 	     * Well, it's local -- go look for it.
   3709 	     */
   3710 	    name[0] = *str;
   3711 	    name[1] = '\0';
   3712 	    v = VarFind(name, ctxt, 0);
   3713 
   3714 	    if (v != NULL) {
   3715 		/*
   3716 		 * No need for nested expansion or anything, as we're
   3717 		 * the only one who sets these things and we sure don't
   3718 		 * but nested invocations in them...
   3719 		 */
   3720 		nstr = Buf_GetAll(&v->val, NULL);
   3721 
   3722 		if (str[1] == 'D') {
   3723 		    nstr = VarModify(ctxt, &parsestate, nstr, VarHead,
   3724 				    NULL);
   3725 		} else {
   3726 		    nstr = VarModify(ctxt, &parsestate, nstr, VarTail,
   3727 				    NULL);
   3728 		}
   3729 		/*
   3730 		 * Resulting string is dynamically allocated, so
   3731 		 * tell caller to free it.
   3732 		 */
   3733 		*freePtr = nstr;
   3734 		*lengthPtr = tstr-start+1;
   3735 		Buf_Destroy(&buf, TRUE);
   3736 		VarFreeEnv(v, TRUE);
   3737 		return nstr;
   3738 	    }
   3739 	}
   3740 
   3741 	if (v == NULL) {
   3742 	    if (((vlen == 1) ||
   3743 		 (((vlen == 2) && (str[1] == 'F' || str[1] == 'D')))) &&
   3744 		((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
   3745 	    {
   3746 		/*
   3747 		 * If substituting a local variable in a non-local context,
   3748 		 * assume it's for dynamic source stuff. We have to handle
   3749 		 * this specially and return the longhand for the variable
   3750 		 * with the dollar sign escaped so it makes it back to the
   3751 		 * caller. Only four of the local variables are treated
   3752 		 * specially as they are the only four that will be set
   3753 		 * when dynamic sources are expanded.
   3754 		 */
   3755 		switch (*str) {
   3756 		    case '@':
   3757 		    case '%':
   3758 		    case '*':
   3759 		    case '!':
   3760 			dynamic = TRUE;
   3761 			break;
   3762 		}
   3763 	    } else if ((vlen > 2) && (*str == '.') &&
   3764 		       isupper((unsigned char) str[1]) &&
   3765 		       ((ctxt == VAR_CMD) || (ctxt == VAR_GLOBAL)))
   3766 	    {
   3767 		int	len;
   3768 
   3769 		len = vlen - 1;
   3770 		if ((strncmp(str, ".TARGET", len) == 0) ||
   3771 		    (strncmp(str, ".ARCHIVE", len) == 0) ||
   3772 		    (strncmp(str, ".PREFIX", len) == 0) ||
   3773 		    (strncmp(str, ".MEMBER", len) == 0))
   3774 		{
   3775 		    dynamic = TRUE;
   3776 		}
   3777 	    }
   3778 
   3779 	    if (!haveModifier) {
   3780 		/*
   3781 		 * No modifiers -- have specification length so we can return
   3782 		 * now.
   3783 		 */
   3784 		*lengthPtr = tstr - start + 1;
   3785 		if (dynamic) {
   3786 		    char *pstr = bmake_strndup(start, *lengthPtr);
   3787 		    *freePtr = pstr;
   3788 		    Buf_Destroy(&buf, TRUE);
   3789 		    return(pstr);
   3790 		} else {
   3791 		    Buf_Destroy(&buf, TRUE);
   3792 		    return (errnum ? var_Error : varNoError);
   3793 		}
   3794 	    } else {
   3795 		/*
   3796 		 * Still need to get to the end of the variable specification,
   3797 		 * so kludge up a Var structure for the modifications
   3798 		 */
   3799 		v = bmake_malloc(sizeof(Var));
   3800 		v->name = UNCONST(str);
   3801 		Buf_Init(&v->val, 1);
   3802 		v->flags = VAR_JUNK;
   3803 		Buf_Destroy(&buf, FALSE);
   3804 	    }
   3805 	} else
   3806 	    Buf_Destroy(&buf, TRUE);
   3807     }
   3808 
   3809     if (v->flags & VAR_IN_USE) {
   3810 	Fatal("Variable %s is recursive.", v->name);
   3811 	/*NOTREACHED*/
   3812     } else {
   3813 	v->flags |= VAR_IN_USE;
   3814     }
   3815     /*
   3816      * Before doing any modification, we have to make sure the value
   3817      * has been fully expanded. If it looks like recursion might be
   3818      * necessary (there's a dollar sign somewhere in the variable's value)
   3819      * we just call Var_Subst to do any other substitutions that are
   3820      * necessary. Note that the value returned by Var_Subst will have
   3821      * been dynamically-allocated, so it will need freeing when we
   3822      * return.
   3823      */
   3824     nstr = Buf_GetAll(&v->val, NULL);
   3825     if (strchr(nstr, '$') != NULL) {
   3826 	nstr = Var_Subst(NULL, nstr, ctxt, errnum);
   3827 	*freePtr = nstr;
   3828     }
   3829 
   3830     v->flags &= ~VAR_IN_USE;
   3831 
   3832     if ((nstr != NULL) && haveModifier) {
   3833 	int used;
   3834 	/*
   3835 	 * Skip initial colon.
   3836 	 */
   3837 	tstr++;
   3838 
   3839 	nstr = ApplyModifiers(nstr, tstr, startc, endc,
   3840 			      v, ctxt, errnum, &used, freePtr);
   3841 	tstr += used;
   3842     }
   3843     if (*tstr) {
   3844 	*lengthPtr = tstr - start + 1;
   3845     } else {
   3846 	*lengthPtr = tstr - start;
   3847     }
   3848 
   3849     if (v->flags & VAR_FROM_ENV) {
   3850 	Boolean	  destroy = FALSE;
   3851 
   3852 	if (nstr != Buf_GetAll(&v->val, NULL)) {
   3853 	    destroy = TRUE;
   3854 	} else {
   3855 	    /*
   3856 	     * Returning the value unmodified, so tell the caller to free
   3857 	     * the thing.
   3858 	     */
   3859 	    *freePtr = nstr;
   3860 	}
   3861 	VarFreeEnv(v, destroy);
   3862     } else if (v->flags & VAR_JUNK) {
   3863 	/*
   3864 	 * Perform any free'ing needed and set *freePtr to NULL so the caller
   3865 	 * doesn't try to free a static pointer.
   3866 	 * If VAR_KEEP is also set then we want to keep str as is.
   3867 	 */
   3868 	if (!(v->flags & VAR_KEEP)) {
   3869 	    if (*freePtr) {
   3870 		free(nstr);
   3871 		*freePtr = NULL;
   3872 	    }
   3873 	    if (dynamic) {
   3874 		nstr = bmake_strndup(start, *lengthPtr);
   3875 		*freePtr = nstr;
   3876 	    } else {
   3877 		nstr = errnum ? var_Error : varNoError;
   3878 	    }
   3879 	}
   3880 	if (nstr != Buf_GetAll(&v->val, NULL))
   3881 	    Buf_Destroy(&v->val, TRUE);
   3882 	free(v->name);
   3883 	free(v);
   3884     }
   3885     return (nstr);
   3886 }
   3887 
   3888 /*-
   3889  *-----------------------------------------------------------------------
   3890  * Var_Subst  --
   3891  *	Substitute for all variables in the given string in the given context
   3892  *	If undefErr is TRUE, Parse_Error will be called when an undefined
   3893  *	variable is encountered.
   3894  *
   3895  * Input:
   3896  *	var		Named variable || NULL for all
   3897  *	str		the string which to substitute
   3898  *	ctxt		the context wherein to find variables
   3899  *	undefErr	TRUE if undefineds are an error
   3900  *
   3901  * Results:
   3902  *	The resulting string.
   3903  *
   3904  * Side Effects:
   3905  *	None. The old string must be freed by the caller
   3906  *-----------------------------------------------------------------------
   3907  */
   3908 char *
   3909 Var_Subst(const char *var, const char *str, GNode *ctxt, Boolean undefErr)
   3910 {
   3911     Buffer  	  buf;		    /* Buffer for forming things */
   3912     char    	  *val;		    /* Value to substitute for a variable */
   3913     int		  length;   	    /* Length of the variable invocation */
   3914     Boolean	  trailingBslash;   /* variable ends in \ */
   3915     void 	  *freeIt = NULL;    /* Set if it should be freed */
   3916     static Boolean errorReported;   /* Set true if an error has already
   3917 				     * been reported to prevent a plethora
   3918 				     * of messages when recursing */
   3919 
   3920     Buf_Init(&buf, 0);
   3921     errorReported = FALSE;
   3922     trailingBslash = FALSE;
   3923 
   3924     while (*str) {
   3925 	if (*str == '\n' && trailingBslash)
   3926 	    Buf_AddByte(&buf, ' ');
   3927 	if (var == NULL && (*str == '$') && (str[1] == '$')) {
   3928 	    /*
   3929 	     * A dollar sign may be escaped either with another dollar sign.
   3930 	     * In such a case, we skip over the escape character and store the
   3931 	     * dollar sign into the buffer directly.
   3932 	     */
   3933 	    str++;
   3934 	    Buf_AddByte(&buf, *str);
   3935 	    str++;
   3936 	} else if (*str != '$') {
   3937 	    /*
   3938 	     * Skip as many characters as possible -- either to the end of
   3939 	     * the string or to the next dollar sign (variable invocation).
   3940 	     */
   3941 	    const char  *cp;
   3942 
   3943 	    for (cp = str++; *str != '$' && *str != '\0'; str++)
   3944 		continue;
   3945 	    Buf_AddBytes(&buf, str - cp, cp);
   3946 	} else {
   3947 	    if (var != NULL) {
   3948 		int expand;
   3949 		for (;;) {
   3950 		    if (str[1] == '\0') {
   3951 			/* A trailing $ is kind of a special case */
   3952 			Buf_AddByte(&buf, str[0]);
   3953 			str++;
   3954 			expand = FALSE;
   3955 		    } else if (str[1] != PROPEN && str[1] != BROPEN) {
   3956 			if (str[1] != *var || strlen(var) > 1) {
   3957 			    Buf_AddBytes(&buf, 2, str);
   3958 			    str += 2;
   3959 			    expand = FALSE;
   3960 			}
   3961 			else
   3962 			    expand = TRUE;
   3963 			break;
   3964 		    }
   3965 		    else {
   3966 			const char *p;
   3967 
   3968 			/*
   3969 			 * Scan up to the end of the variable name.
   3970 			 */
   3971 			for (p = &str[2]; *p &&
   3972 			     *p != ':' && *p != PRCLOSE && *p != BRCLOSE; p++)
   3973 			    if (*p == '$')
   3974 				break;
   3975 			/*
   3976 			 * A variable inside the variable. We cannot expand
   3977 			 * the external variable yet, so we try again with
   3978 			 * the nested one
   3979 			 */
   3980 			if (*p == '$') {
   3981 			    Buf_AddBytes(&buf, p - str, str);
   3982 			    str = p;
   3983 			    continue;
   3984 			}
   3985 
   3986 			if (strncmp(var, str + 2, p - str - 2) != 0 ||
   3987 			    var[p - str - 2] != '\0') {
   3988 			    /*
   3989 			     * Not the variable we want to expand, scan
   3990 			     * until the next variable
   3991 			     */
   3992 			    for (;*p != '$' && *p != '\0'; p++)
   3993 				continue;
   3994 			    Buf_AddBytes(&buf, p - str, str);
   3995 			    str = p;
   3996 			    expand = FALSE;
   3997 			}
   3998 			else
   3999 			    expand = TRUE;
   4000 			break;
   4001 		    }
   4002 		}
   4003 		if (!expand)
   4004 		    continue;
   4005 	    }
   4006 
   4007 	    val = Var_Parse(str, ctxt, undefErr, &length, &freeIt);
   4008 
   4009 	    /*
   4010 	     * When we come down here, val should either point to the
   4011 	     * value of this variable, suitably modified, or be NULL.
   4012 	     * Length should be the total length of the potential
   4013 	     * variable invocation (from $ to end character...)
   4014 	     */
   4015 	    if (val == var_Error || val == varNoError) {
   4016 		/*
   4017 		 * If performing old-time variable substitution, skip over
   4018 		 * the variable and continue with the substitution. Otherwise,
   4019 		 * store the dollar sign and advance str so we continue with
   4020 		 * the string...
   4021 		 */
   4022 		if (oldVars) {
   4023 		    str += length;
   4024 		} else if (undefErr) {
   4025 		    /*
   4026 		     * If variable is undefined, complain and skip the
   4027 		     * variable. The complaint will stop us from doing anything
   4028 		     * when the file is parsed.
   4029 		     */
   4030 		    if (!errorReported) {
   4031 			Parse_Error(PARSE_FATAL,
   4032 				     "Undefined variable \"%.*s\"",length,str);
   4033 		    }
   4034 		    str += length;
   4035 		    errorReported = TRUE;
   4036 		} else {
   4037 		    Buf_AddByte(&buf, *str);
   4038 		    str += 1;
   4039 		}
   4040 	    } else {
   4041 		/*
   4042 		 * We've now got a variable structure to store in. But first,
   4043 		 * advance the string pointer.
   4044 		 */
   4045 		str += length;
   4046 
   4047 		/*
   4048 		 * Copy all the characters from the variable value straight
   4049 		 * into the new string.
   4050 		 */
   4051 		length = strlen(val);
   4052 		Buf_AddBytes(&buf, length, val);
   4053 		trailingBslash = length > 0 && val[length - 1] == '\\';
   4054 	    }
   4055 	    if (freeIt) {
   4056 		free(freeIt);
   4057 		freeIt = NULL;
   4058 	    }
   4059 	}
   4060     }
   4061 
   4062     return Buf_Destroy(&buf, FALSE);
   4063 }
   4064 
   4065 /*-
   4066  *-----------------------------------------------------------------------
   4067  * Var_GetTail --
   4068  *	Return the tail from each of a list of words. Used to set the
   4069  *	System V local variables.
   4070  *
   4071  * Input:
   4072  *	file		Filename to modify
   4073  *
   4074  * Results:
   4075  *	The resulting string.
   4076  *
   4077  * Side Effects:
   4078  *	None.
   4079  *
   4080  *-----------------------------------------------------------------------
   4081  */
   4082 #if 0
   4083 char *
   4084 Var_GetTail(char *file)
   4085 {
   4086     return(VarModify(file, VarTail, NULL));
   4087 }
   4088 
   4089 /*-
   4090  *-----------------------------------------------------------------------
   4091  * Var_GetHead --
   4092  *	Find the leading components of a (list of) filename(s).
   4093  *	XXX: VarHead does not replace foo by ., as (sun) System V make
   4094  *	does.
   4095  *
   4096  * Input:
   4097  *	file		Filename to manipulate
   4098  *
   4099  * Results:
   4100  *	The leading components.
   4101  *
   4102  * Side Effects:
   4103  *	None.
   4104  *
   4105  *-----------------------------------------------------------------------
   4106  */
   4107 char *
   4108 Var_GetHead(char *file)
   4109 {
   4110     return(VarModify(file, VarHead, NULL));
   4111 }
   4112 #endif
   4113 
   4114 /*-
   4115  *-----------------------------------------------------------------------
   4116  * Var_Init --
   4117  *	Initialize the module
   4118  *
   4119  * Results:
   4120  *	None
   4121  *
   4122  * Side Effects:
   4123  *	The VAR_CMD and VAR_GLOBAL contexts are created
   4124  *-----------------------------------------------------------------------
   4125  */
   4126 void
   4127 Var_Init(void)
   4128 {
   4129     VAR_GLOBAL = Targ_NewGN("Global");
   4130     VAR_CMD = Targ_NewGN("Command");
   4131 
   4132 }
   4133 
   4134 
   4135 void
   4136 Var_End(void)
   4137 {
   4138 }
   4139 
   4140 
   4141 /****************** PRINT DEBUGGING INFO *****************/
   4142 static void
   4143 VarPrintVar(void *vp)
   4144 {
   4145     Var    *v = (Var *)vp;
   4146     fprintf(debug_file, "%-16s = %s\n", v->name, Buf_GetAll(&v->val, NULL));
   4147 }
   4148 
   4149 /*-
   4150  *-----------------------------------------------------------------------
   4151  * Var_Dump --
   4152  *	print all variables in a context
   4153  *-----------------------------------------------------------------------
   4154  */
   4155 void
   4156 Var_Dump(GNode *ctxt)
   4157 {
   4158     Hash_Search search;
   4159     Hash_Entry *h;
   4160 
   4161     for (h = Hash_EnumFirst(&ctxt->context, &search);
   4162 	 h != NULL;
   4163 	 h = Hash_EnumNext(&search)) {
   4164 	    VarPrintVar(Hash_GetValue(h));
   4165     }
   4166 }
   4167