xref: /netbsd-src/usr.bin/make/parse.c (revision 9573504567626934c7ee01c7dce0c4bb1dfe7403)
1 /*	$NetBSD: parse.c,v 1.17 1995/11/02 23:55:03 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
5  * Copyright (c) 1988, 1989 by Adam de Boor
6  * Copyright (c) 1989 by Berkeley Softworks
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Adam de Boor.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)parse.c	5.18 (Berkeley) 2/19/91";
44 #else
45 static char rcsid[] = "$NetBSD: parse.c,v 1.17 1995/11/02 23:55:03 christos Exp $";
46 #endif
47 #endif /* not lint */
48 
49 /*-
50  * parse.c --
51  *	Functions to parse a makefile.
52  *
53  *	One function, Parse_Init, must be called before any functions
54  *	in this module are used. After that, the function Parse_File is the
55  *	main entry point and controls most of the other functions in this
56  *	module.
57  *
58  *	Most important structures are kept in Lsts. Directories for
59  *	the #include "..." function are kept in the 'parseIncPath' Lst, while
60  *	those for the #include <...> are kept in the 'sysIncPath' Lst. The
61  *	targets currently being defined are kept in the 'targets' Lst.
62  *
63  *	The variables 'fname' and 'lineno' are used to track the name
64  *	of the current file and the line number in that file so that error
65  *	messages can be more meaningful.
66  *
67  * Interface:
68  *	Parse_Init	    	    Initialization function which must be
69  *	    	  	    	    called before anything else in this module
70  *	    	  	    	    is used.
71  *
72  *	Parse_End		    Cleanup the module
73  *
74  *	Parse_File	    	    Function used to parse a makefile. It must
75  *	    	  	    	    be given the name of the file, which should
76  *	    	  	    	    already have been opened, and a function
77  *	    	  	    	    to call to read a character from the file.
78  *
79  *	Parse_IsVar	    	    Returns TRUE if the given line is a
80  *	    	  	    	    variable assignment. Used by MainParseArgs
81  *	    	  	    	    to determine if an argument is a target
82  *	    	  	    	    or a variable assignment. Used internally
83  *	    	  	    	    for pretty much the same thing...
84  *
85  *	Parse_Error	    	    Function called when an error occurs in
86  *	    	  	    	    parsing. Used by the variable and
87  *	    	  	    	    conditional modules.
88  *	Parse_MainName	    	    Returns a Lst of the main target to create.
89  */
90 
91 #if __STDC__
92 #include <stdarg.h>
93 #else
94 #include <varargs.h>
95 #endif
96 #include <stdio.h>
97 #include <ctype.h>
98 #include <errno.h>
99 #include <sys/wait.h>
100 #include "make.h"
101 #include "hash.h"
102 #include "dir.h"
103 #include "job.h"
104 #include "buf.h"
105 #include "pathnames.h"
106 
107 /*
108  * These values are returned by ParseEOF to tell Parse_File whether to
109  * CONTINUE parsing, i.e. it had only reached the end of an include file,
110  * or if it's DONE.
111  */
112 #define	CONTINUE	1
113 #define	DONE		0
114 static Lst     	    targets;	/* targets we're working on */
115 static Lst     	    targCmds;	/* command lines for targets */
116 static Boolean	    inLine;	/* true if currently in a dependency
117 				 * line or its commands */
118 typedef struct {
119     char *str;
120     char *ptr;
121 } PTR;
122 
123 static char    	    *fname;	/* name of current file (for errors) */
124 static int          lineno;	/* line number in current file */
125 static FILE   	    *curFILE = NULL; 	/* current makefile */
126 
127 static PTR 	    *curPTR = NULL; 	/* current makefile */
128 
129 static int	    fatals = 0;
130 
131 static GNode	    *mainNode;	/* The main target to create. This is the
132 				 * first target on the first dependency
133 				 * line in the first makefile */
134 /*
135  * Definitions for handling #include specifications
136  */
137 typedef struct IFile {
138     char           *fname;	    /* name of previous file */
139     int             lineno;	    /* saved line number */
140     FILE *          F;		    /* the open stream */
141     PTR *	    p;	    	    /* the char pointer */
142 } IFile;
143 
144 static Lst      includes;  	/* stack of IFiles generated by
145 				 * #includes */
146 Lst         	parseIncPath;	/* list of directories for "..." includes */
147 Lst         	sysIncPath;	/* list of directories for <...> includes */
148 
149 /*-
150  * specType contains the SPECial TYPE of the current target. It is
151  * Not if the target is unspecial. If it *is* special, however, the children
152  * are linked as children of the parent but not vice versa. This variable is
153  * set in ParseDoDependency
154  */
155 typedef enum {
156     Begin,  	    /* .BEGIN */
157     Default,	    /* .DEFAULT */
158     End,    	    /* .END */
159     Ignore,	    /* .IGNORE */
160     Includes,	    /* .INCLUDES */
161     Interrupt,	    /* .INTERRUPT */
162     Libs,	    /* .LIBS */
163     MFlags,	    /* .MFLAGS or .MAKEFLAGS */
164     Main,	    /* .MAIN and we don't have anything user-specified to
165 		     * make */
166     NoExport,	    /* .NOEXPORT */
167     Not,	    /* Not special */
168     NotParallel,    /* .NOTPARALELL */
169     Null,   	    /* .NULL */
170     Order,  	    /* .ORDER */
171     ExPath,	    /* .PATH */
172     Precious,	    /* .PRECIOUS */
173     ExShell,	    /* .SHELL */
174     Silent,	    /* .SILENT */
175     SingleShell,    /* .SINGLESHELL */
176     Suffixes,	    /* .SUFFIXES */
177     Attribute	    /* Generic attribute */
178 } ParseSpecial;
179 
180 static ParseSpecial specType;
181 
182 /*
183  * Predecessor node for handling .ORDER. Initialized to NILGNODE when .ORDER
184  * seen, then set to each successive source on the line.
185  */
186 static GNode	*predecessor;
187 
188 /*
189  * The parseKeywords table is searched using binary search when deciding
190  * if a target or source is special. The 'spec' field is the ParseSpecial
191  * type of the keyword ("Not" if the keyword isn't special as a target) while
192  * the 'op' field is the operator to apply to the list of targets if the
193  * keyword is used as a source ("0" if the keyword isn't special as a source)
194  */
195 static struct {
196     char    	  *name;    	/* Name of keyword */
197     ParseSpecial  spec;	    	/* Type when used as a target */
198     int	    	  op;	    	/* Operator when used as a source */
199 } parseKeywords[] = {
200 { ".BEGIN", 	  Begin,    	0 },
201 { ".DEFAULT",	  Default,  	0 },
202 { ".END",   	  End,	    	0 },
203 { ".EXEC",	  Attribute,   	OP_EXEC },
204 { ".IGNORE",	  Ignore,   	OP_IGNORE },
205 { ".INCLUDES",	  Includes, 	0 },
206 { ".INTERRUPT",	  Interrupt,	0 },
207 { ".INVISIBLE",	  Attribute,   	OP_INVISIBLE },
208 { ".JOIN",  	  Attribute,   	OP_JOIN },
209 { ".LIBS",  	  Libs,	    	0 },
210 { ".MAIN",	  Main,		0 },
211 { ".MAKE",  	  Attribute,   	OP_MAKE },
212 { ".MAKEFLAGS",	  MFlags,   	0 },
213 { ".MFLAGS",	  MFlags,   	0 },
214 { ".NOTMAIN",	  Attribute,   	OP_NOTMAIN },
215 { ".NOTPARALLEL", NotParallel,	0 },
216 { ".NULL",  	  Null,	    	0 },
217 { ".OPTIONAL",	  Attribute,   	OP_OPTIONAL },
218 { ".ORDER", 	  Order,    	0 },
219 { ".PATH",	  ExPath,	0 },
220 { ".PRECIOUS",	  Precious, 	OP_PRECIOUS },
221 { ".RECURSIVE",	  Attribute,	OP_MAKE },
222 { ".SHELL", 	  ExShell,    	0 },
223 { ".SILENT",	  Silent,   	OP_SILENT },
224 { ".SINGLESHELL", SingleShell,	0 },
225 { ".SUFFIXES",	  Suffixes, 	0 },
226 { ".USE",   	  Attribute,   	OP_USE },
227 };
228 
229 static int ParseFindKeyword __P((char *));
230 static int ParseLinkSrc __P((ClientData, ClientData));
231 static int ParseDoOp __P((ClientData, ClientData));
232 static void ParseDoSrc __P((int, char *));
233 static int ParseFindMain __P((ClientData, ClientData));
234 static int ParseAddDir __P((ClientData, ClientData));
235 static int ParseClearPath __P((ClientData, ClientData));
236 static void ParseDoDependency __P((char *));
237 static int ParseAddCmd __P((ClientData, ClientData));
238 static int ParseReadc __P((void));
239 static void ParseUnreadc __P((int));
240 static void ParseHasCommands __P((ClientData));
241 static void ParseDoInclude __P((char *));
242 #ifdef SYSVINCLUDE
243 static void ParseTraditionalInclude __P((char *));
244 #endif
245 static int ParseEOF __P((int));
246 static char *ParseReadLine __P((void));
247 static char *ParseSkipLine __P((int));
248 static void ParseFinishLine __P((void));
249 
250 /*-
251  *----------------------------------------------------------------------
252  * ParseFindKeyword --
253  *	Look in the table of keywords for one matching the given string.
254  *
255  * Results:
256  *	The index of the keyword, or -1 if it isn't there.
257  *
258  * Side Effects:
259  *	None
260  *----------------------------------------------------------------------
261  */
262 static int
263 ParseFindKeyword (str)
264     char	    *str;		/* String to find */
265 {
266     register int    start,
267 		    end,
268 		    cur;
269     register int    diff;
270 
271     start = 0;
272     end = (sizeof(parseKeywords)/sizeof(parseKeywords[0])) - 1;
273 
274     do {
275 	cur = start + ((end - start) / 2);
276 	diff = strcmp (str, parseKeywords[cur].name);
277 
278 	if (diff == 0) {
279 	    return (cur);
280 	} else if (diff < 0) {
281 	    end = cur - 1;
282 	} else {
283 	    start = cur + 1;
284 	}
285     } while (start <= end);
286     return (-1);
287 }
288 
289 /*-
290  * Parse_Error  --
291  *	Error message abort function for parsing. Prints out the context
292  *	of the error (line number and file) as well as the message with
293  *	two optional arguments.
294  *
295  * Results:
296  *	None
297  *
298  * Side Effects:
299  *	"fatals" is incremented if the level is PARSE_FATAL.
300  */
301 /* VARARGS */
302 void
303 #if __STDC__
304 Parse_Error(int type, char *fmt, ...)
305 #else
306 Parse_Error(va_alist)
307 	va_dcl
308 #endif
309 {
310 	va_list ap;
311 #if __STDC__
312 	va_start(ap, fmt);
313 #else
314 	int type;		/* Error type (PARSE_WARNING, PARSE_FATAL) */
315 	char *fmt;
316 
317 	va_start(ap);
318 	type = va_arg(ap, int);
319 	fmt = va_arg(ap, char *);
320 #endif
321 
322 	(void)fprintf(stderr, "\"%s\", line %d: ", fname, lineno);
323 	if (type == PARSE_WARNING)
324 		(void)fprintf(stderr, "warning: ");
325 	(void)vfprintf(stderr, fmt, ap);
326 	va_end(ap);
327 	(void)fprintf(stderr, "\n");
328 	(void)fflush(stderr);
329 	if (type == PARSE_FATAL)
330 		fatals += 1;
331 }
332 
333 /*-
334  *---------------------------------------------------------------------
335  * ParseLinkSrc  --
336  *	Link the parent node to its new child. Used in a Lst_ForEach by
337  *	ParseDoDependency. If the specType isn't 'Not', the parent
338  *	isn't linked as a parent of the child.
339  *
340  * Results:
341  *	Always = 0
342  *
343  * Side Effects:
344  *	New elements are added to the parents list of cgn and the
345  *	children list of cgn. the unmade field of pgn is updated
346  *	to reflect the additional child.
347  *---------------------------------------------------------------------
348  */
349 static int
350 ParseLinkSrc (pgnp, cgnp)
351     ClientData     pgnp;	/* The parent node */
352     ClientData     cgnp;	/* The child node */
353 {
354     GNode          *pgn = (GNode *) pgnp;
355     GNode          *cgn = (GNode *) cgnp;
356     if (Lst_Member (pgn->children, (ClientData)cgn) == NILLNODE) {
357 	(void)Lst_AtEnd (pgn->children, (ClientData)cgn);
358 	if (specType == Not) {
359 	    (void)Lst_AtEnd (cgn->parents, (ClientData)pgn);
360 	}
361 	pgn->unmade += 1;
362     }
363     return (0);
364 }
365 
366 /*-
367  *---------------------------------------------------------------------
368  * ParseDoOp  --
369  *	Apply the parsed operator to the given target node. Used in a
370  *	Lst_ForEach call by ParseDoDependency once all targets have
371  *	been found and their operator parsed. If the previous and new
372  *	operators are incompatible, a major error is taken.
373  *
374  * Results:
375  *	Always 0
376  *
377  * Side Effects:
378  *	The type field of the node is altered to reflect any new bits in
379  *	the op.
380  *---------------------------------------------------------------------
381  */
382 static int
383 ParseDoOp (gnp, opp)
384     ClientData     gnp;		/* The node to which the operator is to be
385 				 * applied */
386     ClientData     opp;		/* The operator to apply */
387 {
388     GNode          *gn = (GNode *) gnp;
389     int             op = *(int *) opp;
390     /*
391      * If the dependency mask of the operator and the node don't match and
392      * the node has actually had an operator applied to it before, and
393      * the operator actually has some dependency information in it, complain.
394      */
395     if (((op & OP_OPMASK) != (gn->type & OP_OPMASK)) &&
396 	!OP_NOP(gn->type) && !OP_NOP(op))
397     {
398 	Parse_Error (PARSE_FATAL, "Inconsistent operator for %s", gn->name);
399 	return (1);
400     }
401 
402     if ((op == OP_DOUBLEDEP) && ((gn->type & OP_OPMASK) == OP_DOUBLEDEP)) {
403 	/*
404 	 * If the node was the object of a :: operator, we need to create a
405 	 * new instance of it for the children and commands on this dependency
406 	 * line. The new instance is placed on the 'cohorts' list of the
407 	 * initial one (note the initial one is not on its own cohorts list)
408 	 * and the new instance is linked to all parents of the initial
409 	 * instance.
410 	 */
411 	register GNode	*cohort;
412 	LstNode	    	ln;
413 
414 	cohort = Targ_NewGN(gn->name);
415 	/*
416 	 * Duplicate links to parents so graph traversal is simple. Perhaps
417 	 * some type bits should be duplicated?
418 	 *
419 	 * Make the cohort invisible as well to avoid duplicating it into
420 	 * other variables. True, parents of this target won't tend to do
421 	 * anything with their local variables, but better safe than
422 	 * sorry.
423 	 */
424 	Lst_ForEach(gn->parents, ParseLinkSrc, (ClientData)cohort);
425 	cohort->type = OP_DOUBLEDEP|OP_INVISIBLE;
426 	(void)Lst_AtEnd(gn->cohorts, (ClientData)cohort);
427 
428 	/*
429 	 * Replace the node in the targets list with the new copy
430 	 */
431 	ln = Lst_Member(targets, (ClientData)gn);
432 	Lst_Replace(ln, (ClientData)cohort);
433 	gn = cohort;
434     }
435     /*
436      * We don't want to nuke any previous flags (whatever they were) so we
437      * just OR the new operator into the old
438      */
439     gn->type |= op;
440 
441     return (0);
442 }
443 
444 /*-
445  *---------------------------------------------------------------------
446  * ParseDoSrc  --
447  *	Given the name of a source, figure out if it is an attribute
448  *	and apply it to the targets if it is. Else decide if there is
449  *	some attribute which should be applied *to* the source because
450  *	of some special target and apply it if so. Otherwise, make the
451  *	source be a child of the targets in the list 'targets'
452  *
453  * Results:
454  *	None
455  *
456  * Side Effects:
457  *	Operator bits may be added to the list of targets or to the source.
458  *	The targets may have a new source added to their lists of children.
459  *---------------------------------------------------------------------
460  */
461 static void
462 ParseDoSrc (tOp, src)
463     int		tOp;	/* operator (if any) from special targets */
464     char	*src;	/* name of the source to handle */
465 {
466     int		op;	/* operator (if any) from special source */
467     GNode	*gn;
468 
469     op = 0;
470     if (*src == '.' && isupper (src[1])) {
471 	int keywd = ParseFindKeyword(src);
472 	if (keywd != -1) {
473 	    op = parseKeywords[keywd].op;
474 	}
475     }
476     if (op != 0) {
477 	Lst_ForEach (targets, ParseDoOp, (ClientData)&op);
478     } else if (specType == Main) {
479 	/*
480 	 * If we have noted the existence of a .MAIN, it means we need
481 	 * to add the sources of said target to the list of things
482 	 * to create. The string 'src' is likely to be free, so we
483 	 * must make a new copy of it. Note that this will only be
484 	 * invoked if the user didn't specify a target on the command
485 	 * line. This is to allow #ifmake's to succeed, or something...
486 	 */
487 	(void) Lst_AtEnd (create, (ClientData)strdup(src));
488 	/*
489 	 * Add the name to the .TARGETS variable as well, so the user cna
490 	 * employ that, if desired.
491 	 */
492 	Var_Append(".TARGETS", src, VAR_GLOBAL);
493     } else if (specType == Order) {
494 	/*
495 	 * Create proper predecessor/successor links between the previous
496 	 * source and the current one.
497 	 */
498 	gn = Targ_FindNode(src, TARG_CREATE);
499 	if (predecessor != NILGNODE) {
500 	    (void)Lst_AtEnd(predecessor->successors, (ClientData)gn);
501 	    (void)Lst_AtEnd(gn->preds, (ClientData)predecessor);
502 	}
503 	/*
504 	 * The current source now becomes the predecessor for the next one.
505 	 */
506 	predecessor = gn;
507     } else {
508 	/*
509 	 * If the source is not an attribute, we need to find/create
510 	 * a node for it. After that we can apply any operator to it
511 	 * from a special target or link it to its parents, as
512 	 * appropriate.
513 	 *
514 	 * In the case of a source that was the object of a :: operator,
515 	 * the attribute is applied to all of its instances (as kept in
516 	 * the 'cohorts' list of the node) or all the cohorts are linked
517 	 * to all the targets.
518 	 */
519 	gn = Targ_FindNode (src, TARG_CREATE);
520 	if (tOp) {
521 	    gn->type |= tOp;
522 	} else {
523 	    Lst_ForEach (targets, ParseLinkSrc, (ClientData)gn);
524 	}
525 	if ((gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
526 	    register GNode  	*cohort;
527 	    register LstNode	ln;
528 
529 	    for (ln=Lst_First(gn->cohorts); ln != NILLNODE; ln = Lst_Succ(ln)){
530 		cohort = (GNode *)Lst_Datum(ln);
531 		if (tOp) {
532 		    cohort->type |= tOp;
533 		} else {
534 		    Lst_ForEach(targets, ParseLinkSrc, (ClientData)cohort);
535 		}
536 	    }
537 	}
538     }
539 }
540 
541 /*-
542  *-----------------------------------------------------------------------
543  * ParseFindMain --
544  *	Find a real target in the list and set it to be the main one.
545  *	Called by ParseDoDependency when a main target hasn't been found
546  *	yet.
547  *
548  * Results:
549  *	0 if main not found yet, 1 if it is.
550  *
551  * Side Effects:
552  *	mainNode is changed and Targ_SetMain is called.
553  *
554  *-----------------------------------------------------------------------
555  */
556 static int
557 ParseFindMain(gnp, dummy)
558     ClientData	  gnp;	    /* Node to examine */
559     ClientData    dummy;
560 {
561     GNode   	  *gn = (GNode *) gnp;
562     if ((gn->type & (OP_NOTMAIN|OP_USE|OP_EXEC|OP_TRANSFORM)) == 0) {
563 	mainNode = gn;
564 	Targ_SetMain(gn);
565 	return (dummy ? 1 : 1);
566     } else {
567 	return (dummy ? 0 : 0);
568     }
569 }
570 
571 /*-
572  *-----------------------------------------------------------------------
573  * ParseAddDir --
574  *	Front-end for Dir_AddDir to make sure Lst_ForEach keeps going
575  *
576  * Results:
577  *	=== 0
578  *
579  * Side Effects:
580  *	See Dir_AddDir.
581  *
582  *-----------------------------------------------------------------------
583  */
584 static int
585 ParseAddDir(path, name)
586     ClientData	  path;
587     ClientData    name;
588 {
589     Dir_AddDir((Lst) path, (char *) name);
590     return(0);
591 }
592 
593 /*-
594  *-----------------------------------------------------------------------
595  * ParseClearPath --
596  *	Front-end for Dir_ClearPath to make sure Lst_ForEach keeps going
597  *
598  * Results:
599  *	=== 0
600  *
601  * Side Effects:
602  *	See Dir_ClearPath
603  *
604  *-----------------------------------------------------------------------
605  */
606 static int
607 ParseClearPath(path, dummy)
608     ClientData path;
609     ClientData dummy;
610 {
611     Dir_ClearPath((Lst) path);
612     return(dummy ? 0 : 0);
613 }
614 
615 /*-
616  *---------------------------------------------------------------------
617  * ParseDoDependency  --
618  *	Parse the dependency line in line.
619  *
620  * Results:
621  *	None
622  *
623  * Side Effects:
624  *	The nodes of the sources are linked as children to the nodes of the
625  *	targets. Some nodes may be created.
626  *
627  *	We parse a dependency line by first extracting words from the line and
628  * finding nodes in the list of all targets with that name. This is done
629  * until a character is encountered which is an operator character. Currently
630  * these are only ! and :. At this point the operator is parsed and the
631  * pointer into the line advanced until the first source is encountered.
632  * 	The parsed operator is applied to each node in the 'targets' list,
633  * which is where the nodes found for the targets are kept, by means of
634  * the ParseDoOp function.
635  *	The sources are read in much the same way as the targets were except
636  * that now they are expanded using the wildcarding scheme of the C-Shell
637  * and all instances of the resulting words in the list of all targets
638  * are found. Each of the resulting nodes is then linked to each of the
639  * targets as one of its children.
640  *	Certain targets are handled specially. These are the ones detailed
641  * by the specType variable.
642  *	The storing of transformation rules is also taken care of here.
643  * A target is recognized as a transformation rule by calling
644  * Suff_IsTransform. If it is a transformation rule, its node is gotten
645  * from the suffix module via Suff_AddTransform rather than the standard
646  * Targ_FindNode in the target module.
647  *---------------------------------------------------------------------
648  */
649 static void
650 ParseDoDependency (line)
651     char           *line;	/* the line to parse */
652 {
653     char  	   *cp;		/* our current position */
654     GNode 	   *gn;		/* a general purpose temporary node */
655     int             op;		/* the operator on the line */
656     char            savec;	/* a place to save a character */
657     Lst    	    paths;   	/* List of search paths to alter when parsing
658 				 * a list of .PATH targets */
659     int	    	    tOp;    	/* operator from special target */
660     Lst	    	    sources;	/* list of source names after expansion */
661     Lst 	    curTargs;	/* list of target names to be found and added
662 				 * to the targets list */
663 
664     tOp = 0;
665 
666     specType = Not;
667     paths = (Lst)NULL;
668 
669     curTargs = Lst_Init(FALSE);
670 
671     do {
672 	for (cp = line;
673 	     *cp && !isspace (*cp) &&
674 	     (*cp != '!') && (*cp != ':') && (*cp != '(');
675 	     cp++)
676 	{
677 	    if (*cp == '$') {
678 		/*
679 		 * Must be a dynamic source (would have been expanded
680 		 * otherwise), so call the Var module to parse the puppy
681 		 * so we can safely advance beyond it...There should be
682 		 * no errors in this, as they would have been discovered
683 		 * in the initial Var_Subst and we wouldn't be here.
684 		 */
685 		int 	length;
686 		Boolean	freeIt;
687 		char	*result;
688 
689 		result=Var_Parse(cp, VAR_CMD, TRUE, &length, &freeIt);
690 
691 		if (freeIt) {
692 		    free(result);
693 		}
694 		cp += length-1;
695 	    }
696 	    continue;
697 	}
698 	if (*cp == '(') {
699 	    /*
700 	     * Archives must be handled specially to make sure the OP_ARCHV
701 	     * flag is set in their 'type' field, for one thing, and because
702 	     * things like "archive(file1.o file2.o file3.o)" are permissible.
703 	     * Arch_ParseArchive will set 'line' to be the first non-blank
704 	     * after the archive-spec. It creates/finds nodes for the members
705 	     * and places them on the given list, returning SUCCESS if all
706 	     * went well and FAILURE if there was an error in the
707 	     * specification. On error, line should remain untouched.
708 	     */
709 	    if (Arch_ParseArchive (&line, targets, VAR_CMD) != SUCCESS) {
710 		Parse_Error (PARSE_FATAL,
711 			     "Error in archive specification: \"%s\"", line);
712 		return;
713 	    } else {
714 		continue;
715 	    }
716 	}
717 	savec = *cp;
718 
719 	if (!*cp) {
720 	    /*
721 	     * Ending a dependency line without an operator is a Bozo
722 	     * no-no
723 	     */
724 	    Parse_Error (PARSE_FATAL, "Need an operator");
725 	    return;
726 	}
727 	*cp = '\0';
728 	/*
729 	 * Have a word in line. See if it's a special target and set
730 	 * specType to match it.
731 	 */
732 	if (*line == '.' && isupper (line[1])) {
733 	    /*
734 	     * See if the target is a special target that must have it
735 	     * or its sources handled specially.
736 	     */
737 	    int keywd = ParseFindKeyword(line);
738 	    if (keywd != -1) {
739 		if (specType == ExPath && parseKeywords[keywd].spec != ExPath) {
740 		    Parse_Error(PARSE_FATAL, "Mismatched special targets");
741 		    return;
742 		}
743 
744 		specType = parseKeywords[keywd].spec;
745 		tOp = parseKeywords[keywd].op;
746 
747 		/*
748 		 * Certain special targets have special semantics:
749 		 *	.PATH		Have to set the dirSearchPath
750 		 *			variable too
751 		 *	.MAIN		Its sources are only used if
752 		 *			nothing has been specified to
753 		 *			create.
754 		 *	.DEFAULT    	Need to create a node to hang
755 		 *			commands on, but we don't want
756 		 *			it in the graph, nor do we want
757 		 *			it to be the Main Target, so we
758 		 *			create it, set OP_NOTMAIN and
759 		 *			add it to the list, setting
760 		 *			DEFAULT to the new node for
761 		 *			later use. We claim the node is
762 		 *	    	    	A transformation rule to make
763 		 *	    	    	life easier later, when we'll
764 		 *	    	    	use Make_HandleUse to actually
765 		 *	    	    	apply the .DEFAULT commands.
766 		 *	.BEGIN
767 		 *	.END
768 		 *	.INTERRUPT  	Are not to be considered the
769 		 *			main target.
770 		 *  	.NOTPARALLEL	Make only one target at a time.
771 		 *  	.SINGLESHELL	Create a shell for each command.
772 		 *  	.ORDER	    	Must set initial predecessor to NIL
773 		 */
774 		switch (specType) {
775 		    case ExPath:
776 			if (paths == NULL) {
777 			    paths = Lst_Init(FALSE);
778 			}
779 			(void)Lst_AtEnd(paths, (ClientData)dirSearchPath);
780 			break;
781 		    case Main:
782 			if (!Lst_IsEmpty(create)) {
783 			    specType = Not;
784 			}
785 			break;
786 		    case Begin:
787 		    case End:
788 		    case Interrupt:
789 			gn = Targ_FindNode(line, TARG_CREATE);
790 			gn->type |= OP_NOTMAIN;
791 			(void)Lst_AtEnd(targets, (ClientData)gn);
792 			break;
793 		    case Default:
794 			gn = Targ_NewGN(".DEFAULT");
795 			gn->type |= (OP_NOTMAIN|OP_TRANSFORM);
796 			(void)Lst_AtEnd(targets, (ClientData)gn);
797 			DEFAULT = gn;
798 			break;
799 		    case NotParallel:
800 		    {
801 			extern int  maxJobs;
802 
803 			maxJobs = 1;
804 			break;
805 		    }
806 		    case SingleShell:
807 			compatMake = 1;
808 			break;
809 		    case Order:
810 			predecessor = NILGNODE;
811 			break;
812 		    default:
813 			break;
814 		}
815 	    } else if (strncmp (line, ".PATH", 5) == 0) {
816 		/*
817 		 * .PATH<suffix> has to be handled specially.
818 		 * Call on the suffix module to give us a path to
819 		 * modify.
820 		 */
821 		Lst 	path;
822 
823 		specType = ExPath;
824 		path = Suff_GetPath (&line[5]);
825 		if (path == NILLST) {
826 		    Parse_Error (PARSE_FATAL,
827 				 "Suffix '%s' not defined (yet)",
828 				 &line[5]);
829 		    return;
830 		} else {
831 		    if (paths == (Lst)NULL) {
832 			paths = Lst_Init(FALSE);
833 		    }
834 		    (void)Lst_AtEnd(paths, (ClientData)path);
835 		}
836 	    }
837 	}
838 
839 	/*
840 	 * Have word in line. Get or create its node and stick it at
841 	 * the end of the targets list
842 	 */
843 	if ((specType == Not) && (*line != '\0')) {
844 	    if (Dir_HasWildcards(line)) {
845 		/*
846 		 * Targets are to be sought only in the current directory,
847 		 * so create an empty path for the thing. Note we need to
848 		 * use Dir_Destroy in the destruction of the path as the
849 		 * Dir module could have added a directory to the path...
850 		 */
851 		Lst	    emptyPath = Lst_Init(FALSE);
852 
853 		Dir_Expand(line, emptyPath, curTargs);
854 
855 		Lst_Destroy(emptyPath, Dir_Destroy);
856 	    } else {
857 		/*
858 		 * No wildcards, but we want to avoid code duplication,
859 		 * so create a list with the word on it.
860 		 */
861 		(void)Lst_AtEnd(curTargs, (ClientData)line);
862 	    }
863 
864 	    while(!Lst_IsEmpty(curTargs)) {
865 		char	*targName = (char *)Lst_DeQueue(curTargs);
866 
867 		if (!Suff_IsTransform (targName)) {
868 		    gn = Targ_FindNode (targName, TARG_CREATE);
869 		} else {
870 		    gn = Suff_AddTransform (targName);
871 		}
872 
873 		(void)Lst_AtEnd (targets, (ClientData)gn);
874 	    }
875 	} else if (specType == ExPath && *line != '.' && *line != '\0') {
876 	    Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", line);
877 	}
878 
879 	*cp = savec;
880 	/*
881 	 * If it is a special type and not .PATH, it's the only target we
882 	 * allow on this line...
883 	 */
884 	if (specType != Not && specType != ExPath) {
885 	    Boolean warn = FALSE;
886 
887 	    while ((*cp != '!') && (*cp != ':') && *cp) {
888 		if (*cp != ' ' && *cp != '\t') {
889 		    warn = TRUE;
890 		}
891 		cp++;
892 	    }
893 	    if (warn) {
894 		Parse_Error(PARSE_WARNING, "Extra target ignored");
895 	    }
896 	} else {
897 	    while (*cp && isspace (*cp)) {
898 		cp++;
899 	    }
900 	}
901 	line = cp;
902     } while ((*line != '!') && (*line != ':') && *line);
903 
904     /*
905      * Don't need the list of target names anymore...
906      */
907     Lst_Destroy(curTargs, NOFREE);
908 
909     if (!Lst_IsEmpty(targets)) {
910 	switch(specType) {
911 	    default:
912 		Parse_Error(PARSE_WARNING, "Special and mundane targets don't mix. Mundane ones ignored");
913 		break;
914 	    case Default:
915 	    case Begin:
916 	    case End:
917 	    case Interrupt:
918 		/*
919 		 * These four create nodes on which to hang commands, so
920 		 * targets shouldn't be empty...
921 		 */
922 	    case Not:
923 		/*
924 		 * Nothing special here -- targets can be empty if it wants.
925 		 */
926 		break;
927 	}
928     }
929 
930     /*
931      * Have now parsed all the target names. Must parse the operator next. The
932      * result is left in  op .
933      */
934     if (*cp == '!') {
935 	op = OP_FORCE;
936     } else if (*cp == ':') {
937 	if (cp[1] == ':') {
938 	    op = OP_DOUBLEDEP;
939 	    cp++;
940 	} else {
941 	    op = OP_DEPENDS;
942 	}
943     } else {
944 	Parse_Error (PARSE_FATAL, "Missing dependency operator");
945 	return;
946     }
947 
948     cp++;			/* Advance beyond operator */
949 
950     Lst_ForEach (targets, ParseDoOp, (ClientData)&op);
951 
952     /*
953      * Get to the first source
954      */
955     while (*cp && isspace (*cp)) {
956 	cp++;
957     }
958     line = cp;
959 
960     /*
961      * Several special targets take different actions if present with no
962      * sources:
963      *	a .SUFFIXES line with no sources clears out all old suffixes
964      *	a .PRECIOUS line makes all targets precious
965      *	a .IGNORE line ignores errors for all targets
966      *	a .SILENT line creates silence when making all targets
967      *	a .PATH removes all directories from the search path(s).
968      */
969     if (!*line) {
970 	switch (specType) {
971 	    case Suffixes:
972 		Suff_ClearSuffixes ();
973 		break;
974 	    case Precious:
975 		allPrecious = TRUE;
976 		break;
977 	    case Ignore:
978 		ignoreErrors = TRUE;
979 		break;
980 	    case Silent:
981 		beSilent = TRUE;
982 		break;
983 	    case ExPath:
984 		Lst_ForEach(paths, ParseClearPath, (ClientData)NULL);
985 		break;
986 	    default:
987 		break;
988 	}
989     } else if (specType == MFlags) {
990 	/*
991 	 * Call on functions in main.c to deal with these arguments and
992 	 * set the initial character to a null-character so the loop to
993 	 * get sources won't get anything
994 	 */
995 	Main_ParseArgLine (line);
996 	*line = '\0';
997     } else if (specType == ExShell) {
998 	if (Job_ParseShell (line) != SUCCESS) {
999 	    Parse_Error (PARSE_FATAL, "improper shell specification");
1000 	    return;
1001 	}
1002 	*line = '\0';
1003     } else if ((specType == NotParallel) || (specType == SingleShell)) {
1004 	*line = '\0';
1005     }
1006 
1007     /*
1008      * NOW GO FOR THE SOURCES
1009      */
1010     if ((specType == Suffixes) || (specType == ExPath) ||
1011 	(specType == Includes) || (specType == Libs) ||
1012 	(specType == Null))
1013     {
1014 	while (*line) {
1015 	    /*
1016 	     * If the target was one that doesn't take files as its sources
1017 	     * but takes something like suffixes, we take each
1018 	     * space-separated word on the line as a something and deal
1019 	     * with it accordingly.
1020 	     *
1021 	     * If the target was .SUFFIXES, we take each source as a
1022 	     * suffix and add it to the list of suffixes maintained by the
1023 	     * Suff module.
1024 	     *
1025 	     * If the target was a .PATH, we add the source as a directory
1026 	     * to search on the search path.
1027 	     *
1028 	     * If it was .INCLUDES, the source is taken to be the suffix of
1029 	     * files which will be #included and whose search path should
1030 	     * be present in the .INCLUDES variable.
1031 	     *
1032 	     * If it was .LIBS, the source is taken to be the suffix of
1033 	     * files which are considered libraries and whose search path
1034 	     * should be present in the .LIBS variable.
1035 	     *
1036 	     * If it was .NULL, the source is the suffix to use when a file
1037 	     * has no valid suffix.
1038 	     */
1039 	    char  savec;
1040 	    while (*cp && !isspace (*cp)) {
1041 		cp++;
1042 	    }
1043 	    savec = *cp;
1044 	    *cp = '\0';
1045 	    switch (specType) {
1046 		case Suffixes:
1047 		    Suff_AddSuffix (line);
1048 		    break;
1049 		case ExPath:
1050 		    Lst_ForEach(paths, ParseAddDir, (ClientData)line);
1051 		    break;
1052 		case Includes:
1053 		    Suff_AddInclude (line);
1054 		    break;
1055 		case Libs:
1056 		    Suff_AddLib (line);
1057 		    break;
1058 		case Null:
1059 		    Suff_SetNull (line);
1060 		    break;
1061 		default:
1062 		    break;
1063 	    }
1064 	    *cp = savec;
1065 	    if (savec != '\0') {
1066 		cp++;
1067 	    }
1068 	    while (*cp && isspace (*cp)) {
1069 		cp++;
1070 	    }
1071 	    line = cp;
1072 	}
1073 	if (paths) {
1074 	    Lst_Destroy(paths, NOFREE);
1075 	}
1076     } else {
1077 	while (*line) {
1078 	    /*
1079 	     * The targets take real sources, so we must beware of archive
1080 	     * specifications (i.e. things with left parentheses in them)
1081 	     * and handle them accordingly.
1082 	     */
1083 	    while (*cp && !isspace (*cp)) {
1084 		if ((*cp == '(') && (cp > line) && (cp[-1] != '$')) {
1085 		    /*
1086 		     * Only stop for a left parenthesis if it isn't at the
1087 		     * start of a word (that'll be for variable changes
1088 		     * later) and isn't preceded by a dollar sign (a dynamic
1089 		     * source).
1090 		     */
1091 		    break;
1092 		} else {
1093 		    cp++;
1094 		}
1095 	    }
1096 
1097 	    if (*cp == '(') {
1098 		GNode	  *gn;
1099 
1100 		sources = Lst_Init (FALSE);
1101 		if (Arch_ParseArchive (&line, sources, VAR_CMD) != SUCCESS) {
1102 		    Parse_Error (PARSE_FATAL,
1103 				 "Error in source archive spec \"%s\"", line);
1104 		    return;
1105 		}
1106 
1107 		while (!Lst_IsEmpty (sources)) {
1108 		    gn = (GNode *) Lst_DeQueue (sources);
1109 		    ParseDoSrc (tOp, gn->name);
1110 		}
1111 		Lst_Destroy (sources, NOFREE);
1112 		cp = line;
1113 	    } else {
1114 		if (*cp) {
1115 		    *cp = '\0';
1116 		    cp += 1;
1117 		}
1118 
1119 		ParseDoSrc (tOp, line);
1120 	    }
1121 	    while (*cp && isspace (*cp)) {
1122 		cp++;
1123 	    }
1124 	    line = cp;
1125 	}
1126     }
1127 
1128     if (mainNode == NILGNODE) {
1129 	/*
1130 	 * If we have yet to decide on a main target to make, in the
1131 	 * absence of any user input, we want the first target on
1132 	 * the first dependency line that is actually a real target
1133 	 * (i.e. isn't a .USE or .EXEC rule) to be made.
1134 	 */
1135 	Lst_ForEach (targets, ParseFindMain, (ClientData)0);
1136     }
1137 
1138 }
1139 
1140 /*-
1141  *---------------------------------------------------------------------
1142  * Parse_IsVar  --
1143  *	Return TRUE if the passed line is a variable assignment. A variable
1144  *	assignment consists of a single word followed by optional whitespace
1145  *	followed by either a += or an = operator.
1146  *	This function is used both by the Parse_File function and main when
1147  *	parsing the command-line arguments.
1148  *
1149  * Results:
1150  *	TRUE if it is. FALSE if it ain't
1151  *
1152  * Side Effects:
1153  *	none
1154  *---------------------------------------------------------------------
1155  */
1156 Boolean
1157 Parse_IsVar (line)
1158     register char  *line;	/* the line to check */
1159 {
1160     register Boolean wasSpace = FALSE;	/* set TRUE if found a space */
1161     register Boolean haveName = FALSE;	/* Set TRUE if have a variable name */
1162     int level = 0;
1163 #define ISEQOPERATOR(c) \
1164 	(((c) == '+') || ((c) == ':') || ((c) == '?') || ((c) == '!'))
1165 
1166     /*
1167      * Skip to variable name
1168      */
1169     for (;(*line == ' ') || (*line == '\t'); line++)
1170 	continue;
1171 
1172     for (; *line != '=' || level != 0; line++)
1173 	switch (*line) {
1174 	case '\0':
1175 	    /*
1176 	     * end-of-line -- can't be a variable assignment.
1177 	     */
1178 	    return FALSE;
1179 
1180 	case ' ':
1181 	case '\t':
1182 	    /*
1183 	     * there can be as much white space as desired so long as there is
1184 	     * only one word before the operator
1185 	     */
1186 	    wasSpace = TRUE;
1187 	    break;
1188 
1189 	case '(':
1190 	case '{':
1191 	    level++;
1192 	    break;
1193 
1194 	case '}':
1195 	case ')':
1196 	    level--;
1197 	    break;
1198 
1199 	default:
1200 	    if (wasSpace && haveName) {
1201 		    if (ISEQOPERATOR(*line)) {
1202 			/*
1203 			 * When an = operator [+?!:] is found, the next
1204 			 * character * must be an = or it ain't a valid
1205 			 * assignment.
1206 			 */
1207 			if (line[1] != '=' && level == 0)
1208 			    return FALSE;
1209 			else
1210 			    return haveName;
1211 		    }
1212 		    else {
1213 			/*
1214 			 * This is the start of another word, so not assignment.
1215 			 */
1216 			return FALSE;
1217 		    }
1218 	    }
1219 	    else {
1220 		haveName = TRUE;
1221 		wasSpace = FALSE;
1222 	    }
1223 	    break;
1224 	}
1225 
1226     return haveName;
1227 }
1228 
1229 /*-
1230  *---------------------------------------------------------------------
1231  * Parse_DoVar  --
1232  *	Take the variable assignment in the passed line and do it in the
1233  *	global context.
1234  *
1235  *	Note: There is a lexical ambiguity with assignment modifier characters
1236  *	in variable names. This routine interprets the character before the =
1237  *	as a modifier. Therefore, an assignment like
1238  *	    C++=/usr/bin/CC
1239  *	is interpreted as "C+ +=" instead of "C++ =".
1240  *
1241  * Results:
1242  *	none
1243  *
1244  * Side Effects:
1245  *	the variable structure of the given variable name is altered in the
1246  *	global context.
1247  *---------------------------------------------------------------------
1248  */
1249 void
1250 Parse_DoVar (line, ctxt)
1251     char            *line;	/* a line guaranteed to be a variable
1252 				 * assignment. This reduces error checks */
1253     GNode   	    *ctxt;    	/* Context in which to do the assignment */
1254 {
1255     char	   *cp;	/* pointer into line */
1256     enum {
1257 	VAR_SUBST, VAR_APPEND, VAR_SHELL, VAR_NORMAL
1258     }	    	    type;   	/* Type of assignment */
1259     char            *opc;	/* ptr to operator character to
1260 				 * null-terminate the variable name */
1261     /*
1262      * Avoid clobbered variable warnings by forcing the compiler
1263      * to ``unregister'' variables
1264      */
1265 #if __GNUC__
1266     (void) &cp;
1267     (void) &line;
1268 #endif
1269 
1270     /*
1271      * Skip to variable name
1272      */
1273     while ((*line == ' ') || (*line == '\t')) {
1274 	line++;
1275     }
1276 
1277     /*
1278      * Skip to operator character, nulling out whitespace as we go
1279      */
1280     for (cp = line + 1; *cp != '='; cp++) {
1281 	if (isspace (*cp)) {
1282 	    *cp = '\0';
1283 	}
1284     }
1285     opc = cp-1;		/* operator is the previous character */
1286     *cp++ = '\0';	/* nuke the = */
1287 
1288     /*
1289      * Check operator type
1290      */
1291     switch (*opc) {
1292 	case '+':
1293 	    type = VAR_APPEND;
1294 	    *opc = '\0';
1295 	    break;
1296 
1297 	case '?':
1298 	    /*
1299 	     * If the variable already has a value, we don't do anything.
1300 	     */
1301 	    *opc = '\0';
1302 	    if (Var_Exists(line, ctxt)) {
1303 		return;
1304 	    } else {
1305 		type = VAR_NORMAL;
1306 	    }
1307 	    break;
1308 
1309 	case ':':
1310 	    type = VAR_SUBST;
1311 	    *opc = '\0';
1312 	    break;
1313 
1314 	case '!':
1315 	    type = VAR_SHELL;
1316 	    *opc = '\0';
1317 	    break;
1318 
1319 	default:
1320 	    type = VAR_NORMAL;
1321 	    break;
1322     }
1323 
1324     while (isspace (*cp)) {
1325 	cp++;
1326     }
1327 
1328     if (type == VAR_APPEND) {
1329 	Var_Append (line, cp, ctxt);
1330     } else if (type == VAR_SUBST) {
1331 	/*
1332 	 * Allow variables in the old value to be undefined, but leave their
1333 	 * invocation alone -- this is done by forcing oldVars to be false.
1334 	 * XXX: This can cause recursive variables, but that's not hard to do,
1335 	 * and this allows someone to do something like
1336 	 *
1337 	 *  CFLAGS = $(.INCLUDES)
1338 	 *  CFLAGS := -I.. $(CFLAGS)
1339 	 *
1340 	 * And not get an error.
1341 	 */
1342 	Boolean	  oldOldVars = oldVars;
1343 
1344 	oldVars = FALSE;
1345 	cp = Var_Subst(NULL, cp, ctxt, FALSE);
1346 	oldVars = oldOldVars;
1347 
1348 	Var_Set(line, cp, ctxt);
1349 	free(cp);
1350     } else if (type == VAR_SHELL) {
1351 	char	*args[4];   	/* Args for invoking the shell */
1352 	int 	fds[2];	    	/* Pipe streams */
1353 	int 	cpid;	    	/* Child PID */
1354 	int 	pid;	    	/* PID from wait() */
1355 	Boolean	freeCmd;    	/* TRUE if the command needs to be freed, i.e.
1356 				 * if any variable expansion was performed */
1357 
1358 	/*
1359 	 * Avoid clobbered variable warnings by forcing the compiler
1360 	 * to ``unregister'' variables
1361 	 */
1362 #if __GNUC__
1363 	(void) &freeCmd;
1364 #endif
1365 
1366 	/*
1367 	 * Set up arguments for shell
1368 	 */
1369 	args[0] = "sh";
1370 	args[1] = "-c";
1371 	if (strchr(cp, '$') != (char *)NULL) {
1372 	    /*
1373 	     * There's a dollar sign in the command, so perform variable
1374 	     * expansion on the whole thing. The resulting string will need
1375 	     * freeing when we're done, so set freeCmd to TRUE.
1376 	     */
1377 	    args[2] = Var_Subst(NULL, cp, VAR_CMD, TRUE);
1378 	    freeCmd = TRUE;
1379 	} else {
1380 	    args[2] = cp;
1381 	    freeCmd = FALSE;
1382 	}
1383 	args[3] = (char *)NULL;
1384 
1385 	/*
1386 	 * Open a pipe for fetching its output
1387 	 */
1388 	pipe(fds);
1389 
1390 	/*
1391 	 * Fork
1392 	 */
1393 	cpid = vfork();
1394 	if (cpid == 0) {
1395 	    /*
1396 	     * Close input side of pipe
1397 	     */
1398 	    close(fds[0]);
1399 
1400 	    /*
1401 	     * Duplicate the output stream to the shell's output, then
1402 	     * shut the extra thing down. Note we don't fetch the error
1403 	     * stream...why not? Why?
1404 	     */
1405 	    dup2(fds[1], 1);
1406 	    close(fds[1]);
1407 
1408 	    execv("/bin/sh", args);
1409 	    _exit(1);
1410 	} else if (cpid < 0) {
1411 	    /*
1412 	     * Couldn't fork -- tell the user and make the variable null
1413 	     */
1414 	    Parse_Error(PARSE_WARNING, "Couldn't exec \"%s\"", cp);
1415 	    Var_Set(line, "", ctxt);
1416 	} else {
1417 	    int	status;
1418 	    int cc;
1419 	    Buffer buf;
1420 	    char *res;
1421 
1422 	    /*
1423 	     * No need for the writing half
1424 	     */
1425 	    close(fds[1]);
1426 
1427 	    buf = Buf_Init (MAKE_BSIZE);
1428 
1429 	    do {
1430 		char   result[BUFSIZ];
1431 		cc = read(fds[0], result, sizeof(result));
1432 		if (cc > 0)
1433 		    Buf_AddBytes(buf, cc, (Byte *) result);
1434 	    }
1435 	    while (cc > 0 || (cc == -1 && errno == EINTR));
1436 
1437 	    /*
1438 	     * Close the input side of the pipe.
1439 	     */
1440 	    close(fds[0]);
1441 
1442 	    /*
1443 	     * Wait for the process to exit.
1444 	     */
1445 	    while(((pid = wait(&status)) != cpid) && (pid >= 0))
1446 		continue;
1447 
1448 	    res = (char *)Buf_GetAll (buf, &cc);
1449 	    Buf_Destroy (buf, FALSE);
1450 
1451 	    if (cc == 0) {
1452 		/*
1453 		 * Couldn't read the child's output -- tell the user and
1454 		 * set the variable to null
1455 		 */
1456 		Parse_Error(PARSE_WARNING, "Couldn't read shell's output");
1457 	    }
1458 
1459 	    if (status) {
1460 		/*
1461 		 * Child returned an error -- tell the user but still use
1462 		 * the result.
1463 		 */
1464 		Parse_Error(PARSE_WARNING, "\"%s\" returned non-zero", cp);
1465 	    }
1466 
1467 	    /*
1468 	     * Null-terminate the result, convert newlines to spaces and
1469 	     * install it in the variable.
1470 	     */
1471 	    res[cc] = '\0';
1472 	    cp = &res[cc] - 1;
1473 
1474 	    if (*cp == '\n') {
1475 		/*
1476 		 * A final newline is just stripped
1477 		 */
1478 		*cp-- = '\0';
1479 	    }
1480 	    while (cp >= res) {
1481 		if (*cp == '\n') {
1482 		    *cp = ' ';
1483 		}
1484 		cp--;
1485 	    }
1486 	    Var_Set(line, res, ctxt);
1487 	    free(res);
1488 
1489 	}
1490 	if (freeCmd) {
1491 	    free(args[2]);
1492 	}
1493     } else {
1494 	/*
1495 	 * Normal assignment -- just do it.
1496 	 */
1497 	Var_Set (line, cp, ctxt);
1498     }
1499 }
1500 
1501 /*-
1502  * ParseAddCmd  --
1503  *	Lst_ForEach function to add a command line to all targets
1504  *
1505  * Results:
1506  *	Always 0
1507  *
1508  * Side Effects:
1509  *	A new element is added to the commands list of the node.
1510  */
1511 static int
1512 ParseAddCmd(gnp, cmd)
1513     ClientData gnp;	/* the node to which the command is to be added */
1514     ClientData cmd;	/* the command to add */
1515 {
1516     GNode *gn = (GNode *) gnp;
1517     /* if target already supplied, ignore commands */
1518     if (!(gn->type & OP_HAS_COMMANDS))
1519 	(void)Lst_AtEnd(gn->commands, cmd);
1520     return(0);
1521 }
1522 
1523 /*-
1524  *-----------------------------------------------------------------------
1525  * ParseHasCommands --
1526  *	Callback procedure for Parse_File when destroying the list of
1527  *	targets on the last dependency line. Marks a target as already
1528  *	having commands if it does, to keep from having shell commands
1529  *	on multiple dependency lines.
1530  *
1531  * Results:
1532  *	None
1533  *
1534  * Side Effects:
1535  *	OP_HAS_COMMANDS may be set for the target.
1536  *
1537  *-----------------------------------------------------------------------
1538  */
1539 static void
1540 ParseHasCommands(gnp)
1541     ClientData 	  gnp;	    /* Node to examine */
1542 {
1543     GNode *gn = (GNode *) gnp;
1544     if (!Lst_IsEmpty(gn->commands)) {
1545 	gn->type |= OP_HAS_COMMANDS;
1546     }
1547 }
1548 
1549 /*-
1550  *-----------------------------------------------------------------------
1551  * Parse_AddIncludeDir --
1552  *	Add a directory to the path searched for included makefiles
1553  *	bracketed by double-quotes. Used by functions in main.c
1554  *
1555  * Results:
1556  *	None.
1557  *
1558  * Side Effects:
1559  *	The directory is appended to the list.
1560  *
1561  *-----------------------------------------------------------------------
1562  */
1563 void
1564 Parse_AddIncludeDir (dir)
1565     char    	  *dir;	    /* The name of the directory to add */
1566 {
1567     Dir_AddDir (parseIncPath, dir);
1568 }
1569 
1570 /*-
1571  *---------------------------------------------------------------------
1572  * ParseDoInclude  --
1573  *	Push to another file.
1574  *
1575  *	The input is the line minus the #include. A file spec is a string
1576  *	enclosed in <> or "". The former is looked for only in sysIncPath.
1577  *	The latter in . and the directories specified by -I command line
1578  *	options
1579  *
1580  * Results:
1581  *	None
1582  *
1583  * Side Effects:
1584  *	A structure is added to the includes Lst and readProc, lineno,
1585  *	fname and curFILE are altered for the new file
1586  *---------------------------------------------------------------------
1587  */
1588 static void
1589 ParseDoInclude (file)
1590     char          *file;	/* file specification */
1591 {
1592     char          *fullname;	/* full pathname of file */
1593     IFile         *oldFile;	/* state associated with current file */
1594     char          endc;	    	/* the character which ends the file spec */
1595     char          *cp;		/* current position in file spec */
1596     Boolean 	  isSystem; 	/* TRUE if makefile is a system makefile */
1597 
1598     /*
1599      * Skip to delimiter character so we know where to look
1600      */
1601     while ((*file == ' ') || (*file == '\t')) {
1602 	file++;
1603     }
1604 
1605     if ((*file != '"') && (*file != '<')) {
1606 	Parse_Error (PARSE_FATAL,
1607 	    ".include filename must be delimited by '\"' or '<'");
1608 	return;
1609     }
1610 
1611     /*
1612      * Set the search path on which to find the include file based on the
1613      * characters which bracket its name. Angle-brackets imply it's
1614      * a system Makefile while double-quotes imply it's a user makefile
1615      */
1616     if (*file == '<') {
1617 	isSystem = TRUE;
1618 	endc = '>';
1619     } else {
1620 	isSystem = FALSE;
1621 	endc = '"';
1622     }
1623 
1624     /*
1625      * Skip to matching delimiter
1626      */
1627     for (cp = ++file; *cp && *cp != endc; cp++) {
1628 	continue;
1629     }
1630 
1631     if (*cp != endc) {
1632 	Parse_Error (PARSE_FATAL,
1633 		     "Unclosed %cinclude filename. '%c' expected",
1634 		     '.', endc);
1635 	return;
1636     }
1637     *cp = '\0';
1638 
1639     /*
1640      * Substitute for any variables in the file name before trying to
1641      * find the thing.
1642      */
1643     file = Var_Subst (NULL, file, VAR_CMD, FALSE);
1644 
1645     /*
1646      * Now we know the file's name and its search path, we attempt to
1647      * find the durn thing. A return of NULL indicates the file don't
1648      * exist.
1649      */
1650     if (!isSystem) {
1651 	/*
1652 	 * Include files contained in double-quotes are first searched for
1653 	 * relative to the including file's location. We don't want to
1654 	 * cd there, of course, so we just tack on the old file's
1655 	 * leading path components and call Dir_FindFile to see if
1656 	 * we can locate the beast.
1657 	 */
1658 	char	  *prefEnd;
1659 
1660 	prefEnd = strrchr (fname, '/');
1661 	if (prefEnd != (char *)NULL) {
1662 	    char  	*newName;
1663 
1664 	    *prefEnd = '\0';
1665 	    if (file[0] == '/')
1666 		newName = strdup(file);
1667 	    else
1668 		newName = str_concat (fname, file, STR_ADDSLASH);
1669 	    fullname = Dir_FindFile (newName, parseIncPath);
1670 	    if (fullname == (char *)NULL) {
1671 		fullname = Dir_FindFile(newName, dirSearchPath);
1672 	    }
1673 	    free (newName);
1674 	    *prefEnd = '/';
1675 	} else {
1676 	    fullname = (char *)NULL;
1677 	}
1678     } else {
1679 	fullname = (char *)NULL;
1680     }
1681 
1682     if (fullname == (char *)NULL) {
1683 	/*
1684 	 * System makefile or makefile wasn't found in same directory as
1685 	 * included makefile. Search for it first on the -I search path,
1686 	 * then on the .PATH search path, if not found in a -I directory.
1687 	 * XXX: Suffix specific?
1688 	 */
1689 	fullname = Dir_FindFile (file, parseIncPath);
1690 	if (fullname == (char *)NULL) {
1691 	    fullname = Dir_FindFile(file, dirSearchPath);
1692 	}
1693     }
1694 
1695     if (fullname == (char *)NULL) {
1696 	/*
1697 	 * Still haven't found the makefile. Look for it on the system
1698 	 * path as a last resort.
1699 	 */
1700 	fullname = Dir_FindFile(file, sysIncPath);
1701     }
1702 
1703     if (fullname == (char *) NULL) {
1704 	*cp = endc;
1705 	Parse_Error (PARSE_FATAL, "Could not find %s", file);
1706 	return;
1707     }
1708 
1709     free(file);
1710 
1711     /*
1712      * Once we find the absolute path to the file, we get to save all the
1713      * state from the current file before we can start reading this
1714      * include file. The state is stored in an IFile structure which
1715      * is placed on a list with other IFile structures. The list makes
1716      * a very nice stack to track how we got here...
1717      */
1718     oldFile = (IFile *) emalloc (sizeof (IFile));
1719     oldFile->fname = fname;
1720 
1721     oldFile->F = curFILE;
1722     oldFile->p = curPTR;
1723     oldFile->lineno = lineno;
1724 
1725     (void) Lst_AtFront (includes, (ClientData)oldFile);
1726 
1727     /*
1728      * Once the previous state has been saved, we can get down to reading
1729      * the new file. We set up the name of the file to be the absolute
1730      * name of the include file so error messages refer to the right
1731      * place. Naturally enough, we start reading at line number 0.
1732      */
1733     fname = fullname;
1734     lineno = 0;
1735 
1736     curFILE = fopen (fullname, "r");
1737     curPTR = NULL;
1738     if (curFILE == (FILE * ) NULL) {
1739 	Parse_Error (PARSE_FATAL, "Cannot open %s", fullname);
1740 	/*
1741 	 * Pop to previous file
1742 	 */
1743 	(void) ParseEOF(0);
1744     }
1745 }
1746 
1747 
1748 /*-
1749  *---------------------------------------------------------------------
1750  * Parse_FromString  --
1751  *	Start Parsing from the given string
1752  *
1753  * Results:
1754  *	None
1755  *
1756  * Side Effects:
1757  *	A structure is added to the includes Lst and readProc, lineno,
1758  *	fname and curFILE are altered for the new file
1759  *---------------------------------------------------------------------
1760  */
1761 void
1762 Parse_FromString(str)
1763     char *str;
1764 {
1765     IFile         *oldFile;	/* state associated with this file */
1766 
1767     if (DEBUG(FOR))
1768 	(void) fprintf(stderr, "%s\n----\n", str);
1769 
1770     oldFile = (IFile *) emalloc (sizeof (IFile));
1771     oldFile->lineno = lineno;
1772     oldFile->fname = fname;
1773     oldFile->F = curFILE;
1774     oldFile->p = curPTR;
1775 
1776     (void) Lst_AtFront (includes, (ClientData)oldFile);
1777 
1778     curFILE = NULL;
1779     curPTR = (PTR *) emalloc (sizeof (PTR));
1780     curPTR->str = curPTR->ptr = str;
1781     lineno = 0;
1782     fname = strdup(fname);
1783 }
1784 
1785 
1786 #ifdef SYSVINCLUDE
1787 /*-
1788  *---------------------------------------------------------------------
1789  * ParseTraditionalInclude  --
1790  *	Push to another file.
1791  *
1792  *	The input is the line minus the "include".  The file name is
1793  *	the string following the "include".
1794  *
1795  * Results:
1796  *	None
1797  *
1798  * Side Effects:
1799  *	A structure is added to the includes Lst and readProc, lineno,
1800  *	fname and curFILE are altered for the new file
1801  *---------------------------------------------------------------------
1802  */
1803 static void
1804 ParseTraditionalInclude (file)
1805     char          *file;	/* file specification */
1806 {
1807     char          *fullname;	/* full pathname of file */
1808     IFile         *oldFile;	/* state associated with current file */
1809     char          *cp;		/* current position in file spec */
1810     char	  *prefEnd;
1811 
1812     /*
1813      * Skip over whitespace
1814      */
1815     while ((*file == ' ') || (*file == '\t')) {
1816 	file++;
1817     }
1818 
1819     if (*file == '\0') {
1820 	Parse_Error (PARSE_FATAL,
1821 		     "Filename missing from \"include\"");
1822 	return;
1823     }
1824 
1825     /*
1826      * Skip to end of line or next whitespace
1827      */
1828     for (cp = file; *cp && *cp != '\n' && *cp != '\t' && *cp != ' '; cp++) {
1829 	continue;
1830     }
1831 
1832     *cp = '\0';
1833 
1834     /*
1835      * Substitute for any variables in the file name before trying to
1836      * find the thing.
1837      */
1838     file = Var_Subst (NULL, file, VAR_CMD, FALSE);
1839 
1840     /*
1841      * Now we know the file's name, we attempt to find the durn thing.
1842      * A return of NULL indicates the file don't exist.
1843      *
1844      * Include files are first searched for relative to the including
1845      * file's location. We don't want to cd there, of course, so we
1846      * just tack on the old file's leading path components and call
1847      * Dir_FindFile to see if we can locate the beast.
1848      * XXX - this *does* search in the current directory, right?
1849      */
1850 
1851     prefEnd = strrchr (fname, '/');
1852     if (prefEnd != (char *)NULL) {
1853 	char  	*newName;
1854 
1855 	*prefEnd = '\0';
1856 	newName = str_concat (fname, file, STR_ADDSLASH);
1857 	fullname = Dir_FindFile (newName, parseIncPath);
1858 	if (fullname == (char *)NULL) {
1859 	    fullname = Dir_FindFile(newName, dirSearchPath);
1860 	}
1861 	free (newName);
1862 	*prefEnd = '/';
1863     } else {
1864 	fullname = (char *)NULL;
1865     }
1866 
1867     if (fullname == (char *)NULL) {
1868 	/*
1869 	 * System makefile or makefile wasn't found in same directory as
1870 	 * included makefile. Search for it first on the -I search path,
1871 	 * then on the .PATH search path, if not found in a -I directory.
1872 	 * XXX: Suffix specific?
1873 	 */
1874 	fullname = Dir_FindFile (file, parseIncPath);
1875 	if (fullname == (char *)NULL) {
1876 	    fullname = Dir_FindFile(file, dirSearchPath);
1877 	}
1878     }
1879 
1880     if (fullname == (char *)NULL) {
1881 	/*
1882 	 * Still haven't found the makefile. Look for it on the system
1883 	 * path as a last resort.
1884 	 */
1885 	fullname = Dir_FindFile(file, sysIncPath);
1886     }
1887 
1888     if (fullname == (char *) NULL) {
1889 	Parse_Error (PARSE_FATAL, "Could not find %s", file);
1890 	return;
1891     }
1892 
1893     /*
1894      * Once we find the absolute path to the file, we get to save all the
1895      * state from the current file before we can start reading this
1896      * include file. The state is stored in an IFile structure which
1897      * is placed on a list with other IFile structures. The list makes
1898      * a very nice stack to track how we got here...
1899      */
1900     oldFile = (IFile *) emalloc (sizeof (IFile));
1901     oldFile->fname = fname;
1902 
1903     oldFile->F = curFILE;
1904     oldFile->p = curPTR;
1905     oldFile->lineno = lineno;
1906 
1907     (void) Lst_AtFront (includes, (ClientData)oldFile);
1908 
1909     /*
1910      * Once the previous state has been saved, we can get down to reading
1911      * the new file. We set up the name of the file to be the absolute
1912      * name of the include file so error messages refer to the right
1913      * place. Naturally enough, we start reading at line number 0.
1914      */
1915     fname = fullname;
1916     lineno = 0;
1917 
1918     curFILE = fopen (fullname, "r");
1919     curPTR = NULL;
1920     if (curFILE == (FILE * ) NULL) {
1921 	Parse_Error (PARSE_FATAL, "Cannot open %s", fullname);
1922 	/*
1923 	 * Pop to previous file
1924 	 */
1925 	(void) ParseEOF(1);
1926     }
1927 }
1928 #endif
1929 
1930 /*-
1931  *---------------------------------------------------------------------
1932  * ParseEOF  --
1933  *	Called when EOF is reached in the current file. If we were reading
1934  *	an include file, the includes stack is popped and things set up
1935  *	to go back to reading the previous file at the previous location.
1936  *
1937  * Results:
1938  *	CONTINUE if there's more to do. DONE if not.
1939  *
1940  * Side Effects:
1941  *	The old curFILE, is closed. The includes list is shortened.
1942  *	lineno, curFILE, and fname are changed if CONTINUE is returned.
1943  *---------------------------------------------------------------------
1944  */
1945 static int
1946 ParseEOF (opened)
1947     int opened;
1948 {
1949     IFile     *ifile;	/* the state on the top of the includes stack */
1950 
1951     if (Lst_IsEmpty (includes)) {
1952 	return (DONE);
1953     }
1954 
1955     ifile = (IFile *) Lst_DeQueue (includes);
1956     free ((Address) fname);
1957     fname = ifile->fname;
1958     lineno = ifile->lineno;
1959     if (opened && curFILE)
1960 	(void) fclose (curFILE);
1961     if (curPTR) {
1962 	free((Address) curPTR->str);
1963 	free((Address) curPTR);
1964     }
1965     curFILE = ifile->F;
1966     curPTR = ifile->p;
1967     free ((Address)ifile);
1968     return (CONTINUE);
1969 }
1970 
1971 /*-
1972  *---------------------------------------------------------------------
1973  * ParseReadc  --
1974  *	Read a character from the current file
1975  *
1976  * Results:
1977  *	The character that was read
1978  *
1979  * Side Effects:
1980  *---------------------------------------------------------------------
1981  */
1982 static int
1983 ParseReadc()
1984 {
1985     if (curFILE)
1986 	return fgetc(curFILE);
1987 
1988     if (curPTR && *curPTR->ptr)
1989 	return *curPTR->ptr++;
1990     return EOF;
1991 }
1992 
1993 
1994 /*-
1995  *---------------------------------------------------------------------
1996  * ParseUnreadc  --
1997  *	Put back a character to the current file
1998  *
1999  * Results:
2000  *	None.
2001  *
2002  * Side Effects:
2003  *---------------------------------------------------------------------
2004  */
2005 static void
2006 ParseUnreadc(c)
2007     int c;
2008 {
2009     if (curFILE) {
2010 	ungetc(c, curFILE);
2011 	return;
2012     }
2013     if (curPTR) {
2014 	*--(curPTR->ptr) = c;
2015 	return;
2016     }
2017 }
2018 
2019 
2020 /* ParseSkipLine():
2021  *	Grab the next line
2022  */
2023 static char *
2024 ParseSkipLine(skip)
2025     int skip; 		/* Skip lines that don't start with . */
2026 {
2027     char *line;
2028     int c, lastc = '\0', lineLength;
2029     Buffer buf;
2030 
2031     c = ParseReadc();
2032 
2033     if (skip) {
2034 	/*
2035 	 * Skip lines until get to one that begins with a
2036 	 * special char.
2037 	 */
2038 	while ((c != '.') && (c != EOF)) {
2039 	    while (((c != '\n') || (lastc == '\\')) && (c != EOF))
2040 	    {
2041 		/*
2042 		 * Advance to next unescaped newline
2043 		 */
2044 		if ((lastc = c) == '\n') {
2045 		    lineno++;
2046 		}
2047 		c = ParseReadc();
2048 	    }
2049 	    lineno++;
2050 
2051 	    lastc = c;
2052 	    c = ParseReadc ();
2053 	}
2054     }
2055 
2056     if (c == EOF) {
2057 	Parse_Error (PARSE_FATAL, "Unclosed conditional/for loop");
2058 	return ((char *)NULL);
2059     }
2060 
2061     /*
2062      * Read the entire line into buf
2063      */
2064     buf = Buf_Init (MAKE_BSIZE);
2065     if (c != '\n') {
2066 	do {
2067 	    Buf_AddByte (buf, (Byte)c);
2068 	    c = ParseReadc();
2069 	} while ((c != '\n') && (c != EOF));
2070     }
2071     lineno++;
2072 
2073     Buf_AddByte (buf, (Byte)'\0');
2074     line = (char *)Buf_GetAll (buf, &lineLength);
2075     Buf_Destroy (buf, FALSE);
2076     return line;
2077 }
2078 
2079 
2080 /*-
2081  *---------------------------------------------------------------------
2082  * ParseReadLine --
2083  *	Read an entire line from the input file. Called only by Parse_File.
2084  *	To facilitate escaped newlines and what have you, a character is
2085  *	buffered in 'lastc', which is '\0' when no characters have been
2086  *	read. When we break out of the loop, c holds the terminating
2087  *	character and lastc holds a character that should be added to
2088  *	the line (unless we don't read anything but a terminator).
2089  *
2090  * Results:
2091  *	A line w/o its newline
2092  *
2093  * Side Effects:
2094  *	Only those associated with reading a character
2095  *---------------------------------------------------------------------
2096  */
2097 static char *
2098 ParseReadLine ()
2099 {
2100     Buffer  	  buf;	    	/* Buffer for current line */
2101     register int  c;	      	/* the current character */
2102     register int  lastc;    	/* The most-recent character */
2103     Boolean	  semiNL;     	/* treat semi-colons as newlines */
2104     Boolean	  ignDepOp;   	/* TRUE if should ignore dependency operators
2105 				 * for the purposes of setting semiNL */
2106     Boolean 	  ignComment;	/* TRUE if should ignore comments (in a
2107 				 * shell command */
2108     char 	  *line;    	/* Result */
2109     char          *ep;		/* to strip trailing blanks */
2110     int	    	  lineLength;	/* Length of result */
2111 
2112     semiNL = FALSE;
2113     ignDepOp = FALSE;
2114     ignComment = FALSE;
2115 
2116     /*
2117      * Handle special-characters at the beginning of the line. Either a
2118      * leading tab (shell command) or pound-sign (possible conditional)
2119      * forces us to ignore comments and dependency operators and treat
2120      * semi-colons as semi-colons (by leaving semiNL FALSE). This also
2121      * discards completely blank lines.
2122      */
2123     for (;;) {
2124 	c = ParseReadc();
2125 
2126 	if (c == '\t') {
2127 	    ignComment = ignDepOp = TRUE;
2128 	    break;
2129 	} else if (c == '\n') {
2130 	    lineno++;
2131 	} else if (c == '#') {
2132 	    ParseUnreadc(c);
2133 	    break;
2134 	} else {
2135 	    /*
2136 	     * Anything else breaks out without doing anything
2137 	     */
2138 	    break;
2139 	}
2140     }
2141 
2142     if (c != EOF) {
2143 	lastc = c;
2144 	buf = Buf_Init(MAKE_BSIZE);
2145 
2146 	while (((c = ParseReadc ()) != '\n' || (lastc == '\\')) &&
2147 	       (c != EOF))
2148 	{
2149 test_char:
2150 	    switch(c) {
2151 	    case '\n':
2152 		/*
2153 		 * Escaped newline: read characters until a non-space or an
2154 		 * unescaped newline and replace them all by a single space.
2155 		 * This is done by storing the space over the backslash and
2156 		 * dropping through with the next nonspace. If it is a
2157 		 * semi-colon and semiNL is TRUE, it will be recognized as a
2158 		 * newline in the code below this...
2159 		 */
2160 		lineno++;
2161 		lastc = ' ';
2162 		while ((c = ParseReadc ()) == ' ' || c == '\t') {
2163 		    continue;
2164 		}
2165 		if (c == EOF || c == '\n') {
2166 		    goto line_read;
2167 		} else {
2168 		    /*
2169 		     * Check for comments, semiNL's, etc. -- easier than
2170 		     * ParseUnreadc(c); continue;
2171 		     */
2172 		    goto test_char;
2173 		}
2174 		/*NOTREACHED*/
2175 		break;
2176 
2177 	    case ';':
2178 		/*
2179 		 * Semi-colon: Need to see if it should be interpreted as a
2180 		 * newline
2181 		 */
2182 		if (semiNL) {
2183 		    /*
2184 		     * To make sure the command that may be following this
2185 		     * semi-colon begins with a tab, we push one back into the
2186 		     * input stream. This will overwrite the semi-colon in the
2187 		     * buffer. If there is no command following, this does no
2188 		     * harm, since the newline remains in the buffer and the
2189 		     * whole line is ignored.
2190 		     */
2191 		    ParseUnreadc('\t');
2192 		    goto line_read;
2193 		}
2194 		break;
2195 	    case '=':
2196 		if (!semiNL) {
2197 		    /*
2198 		     * Haven't seen a dependency operator before this, so this
2199 		     * must be a variable assignment -- don't pay attention to
2200 		     * dependency operators after this.
2201 		     */
2202 		    ignDepOp = TRUE;
2203 		} else if (lastc == ':' || lastc == '!') {
2204 		    /*
2205 		     * Well, we've seen a dependency operator already, but it
2206 		     * was the previous character, so this is really just an
2207 		     * expanded variable assignment. Revert semi-colons to
2208 		     * being just semi-colons again and ignore any more
2209 		     * dependency operators.
2210 		     *
2211 		     * XXX: Note that a line like "foo : a:=b" will blow up,
2212 		     * but who'd write a line like that anyway?
2213 		     */
2214 		    ignDepOp = TRUE; semiNL = FALSE;
2215 		}
2216 		break;
2217 	    case '#':
2218 		if (!ignComment) {
2219 		    if (
2220 #if 0
2221 		    compatMake &&
2222 #endif
2223 		    (lastc != '\\')) {
2224 			/*
2225 			 * If the character is a hash mark and it isn't escaped
2226 			 * (or we're being compatible), the thing is a comment.
2227 			 * Skip to the end of the line.
2228 			 */
2229 			do {
2230 			    c = ParseReadc();
2231 			} while ((c != '\n') && (c != EOF));
2232 			goto line_read;
2233 		    } else {
2234 			/*
2235 			 * Don't add the backslash. Just let the # get copied
2236 			 * over.
2237 			 */
2238 			lastc = c;
2239 			continue;
2240 		    }
2241 		}
2242 		break;
2243 	    case ':':
2244 	    case '!':
2245 		if (!ignDepOp && (c == ':' || c == '!')) {
2246 		    /*
2247 		     * A semi-colon is recognized as a newline only on
2248 		     * dependency lines. Dependency lines are lines with a
2249 		     * colon or an exclamation point. Ergo...
2250 		     */
2251 		    semiNL = TRUE;
2252 		}
2253 		break;
2254 	    }
2255 	    /*
2256 	     * Copy in the previous character and save this one in lastc.
2257 	     */
2258 	    Buf_AddByte (buf, (Byte)lastc);
2259 	    lastc = c;
2260 
2261 	}
2262     line_read:
2263 	lineno++;
2264 
2265 	if (lastc != '\0') {
2266 	    Buf_AddByte (buf, (Byte)lastc);
2267 	}
2268 	Buf_AddByte (buf, (Byte)'\0');
2269 	line = (char *)Buf_GetAll (buf, &lineLength);
2270 	Buf_Destroy (buf, FALSE);
2271 
2272 	/*
2273 	 * Strip trailing blanks and tabs from the line.
2274 	 * Do not strip a blank or tab that is preceeded by
2275 	 * a '\'
2276 	 */
2277 	ep = line;
2278 	while (*ep)
2279 	    ++ep;
2280 	while (ep > line && (ep[-1] == ' ' || ep[-1] == '\t')) {
2281 	    if (ep > line + 1 && ep[-2] == '\\')
2282 		break;
2283 	    --ep;
2284 	}
2285 	*ep = 0;
2286 
2287 	if (line[0] == '.') {
2288 	    /*
2289 	     * The line might be a conditional. Ask the conditional module
2290 	     * about it and act accordingly
2291 	     */
2292 	    switch (Cond_Eval (line)) {
2293 	    case COND_SKIP:
2294 		/*
2295 		 * Skip to next conditional that evaluates to COND_PARSE.
2296 		 */
2297 		do {
2298 		    free (line);
2299 		    line = ParseSkipLine(1);
2300 		} while (line && Cond_Eval(line) != COND_PARSE);
2301 		if (line == NULL)
2302 		    break;
2303 		/*FALLTHRU*/
2304 	    case COND_PARSE:
2305 		free ((Address) line);
2306 		line = ParseReadLine();
2307 		break;
2308 	    case COND_INVALID:
2309 		if (For_Eval(line)) {
2310 		    int ok;
2311 		    free(line);
2312 		    do {
2313 			/*
2314 			 * Skip after the matching end
2315 			 */
2316 			line = ParseSkipLine(0);
2317 			if (line == NULL) {
2318 			    Parse_Error (PARSE_FATAL,
2319 				     "Unexpected end of file in for loop.\n");
2320 			    break;
2321 			}
2322 			ok = For_Eval(line);
2323 			free(line);
2324 		    }
2325 		    while (ok);
2326 		    if (line != NULL)
2327 			For_Run();
2328 		    line = ParseReadLine();
2329 		}
2330 		break;
2331 	    }
2332 	}
2333 	return (line);
2334 
2335     } else {
2336 	/*
2337 	 * Hit end-of-file, so return a NULL line to indicate this.
2338 	 */
2339 	return((char *)NULL);
2340     }
2341 }
2342 
2343 /*-
2344  *-----------------------------------------------------------------------
2345  * ParseFinishLine --
2346  *	Handle the end of a dependency group.
2347  *
2348  * Results:
2349  *	Nothing.
2350  *
2351  * Side Effects:
2352  *	inLine set FALSE. 'targets' list destroyed.
2353  *
2354  *-----------------------------------------------------------------------
2355  */
2356 static void
2357 ParseFinishLine()
2358 {
2359     if (inLine) {
2360 	Lst_ForEach(targets, Suff_EndTransform, (ClientData)NULL);
2361 	Lst_Destroy (targets, ParseHasCommands);
2362 	targets = NULL;
2363 	inLine = FALSE;
2364     }
2365 }
2366 
2367 
2368 /*-
2369  *---------------------------------------------------------------------
2370  * Parse_File --
2371  *	Parse a file into its component parts, incorporating it into the
2372  *	current dependency graph. This is the main function and controls
2373  *	almost every other function in this module
2374  *
2375  * Results:
2376  *	None
2377  *
2378  * Side Effects:
2379  *	Loads. Nodes are added to the list of all targets, nodes and links
2380  *	are added to the dependency graph. etc. etc. etc.
2381  *---------------------------------------------------------------------
2382  */
2383 void
2384 Parse_File(name, stream)
2385     char          *name;	/* the name of the file being read */
2386     FILE *	  stream;   	/* Stream open to makefile to parse */
2387 {
2388     register char *cp,		/* pointer into the line */
2389                   *line;	/* the line we're working on */
2390 
2391     inLine = FALSE;
2392     fname = name;
2393     curFILE = stream;
2394     lineno = 0;
2395     fatals = 0;
2396 
2397     do {
2398 	while ((line = ParseReadLine ()) != NULL) {
2399 	    if (*line == '.') {
2400 		/*
2401 		 * Lines that begin with the special character are either
2402 		 * include or undef directives.
2403 		 */
2404 		for (cp = line + 1; isspace (*cp); cp++) {
2405 		    continue;
2406 		}
2407 		if (strncmp (cp, "include", 7) == 0) {
2408 		    ParseDoInclude (cp + 7);
2409 		    goto nextLine;
2410 		} else if (strncmp(cp, "undef", 5) == 0) {
2411 		    char *cp2;
2412 		    for (cp += 5; isspace((unsigned char) *cp); cp++) {
2413 			continue;
2414 		    }
2415 
2416 		    for (cp2 = cp; !isspace((unsigned char) *cp2) &&
2417 				   (*cp2 != '\0'); cp2++) {
2418 			continue;
2419 		    }
2420 
2421 		    *cp2 = '\0';
2422 
2423 		    Var_Delete(cp, VAR_GLOBAL);
2424 		    goto nextLine;
2425 		}
2426 	    }
2427 	    if (*line == '#' || *line == '\0') {
2428 		/* If we're this far, the line must be a comment.
2429 		   (Empty lines are ignored as well) */
2430 		goto nextLine;
2431 	    }
2432 
2433 	    if (*line == '\t') {
2434 		/*
2435 		 * If a line starts with a tab, it can only hope to be
2436 		 * a creation command.
2437 		 */
2438 #ifndef POSIX
2439 	    shellCommand:
2440 #endif
2441 		for (cp = line + 1; isspace (*cp); cp++) {
2442 		    continue;
2443 		}
2444 		if (*cp) {
2445 		    if (inLine) {
2446 			/*
2447 			 * So long as it's not a blank line and we're actually
2448 			 * in a dependency spec, add the command to the list of
2449 			 * commands of all targets in the dependency spec
2450 			 */
2451 			Lst_ForEach (targets, ParseAddCmd, cp);
2452 			Lst_AtEnd(targCmds, (ClientData) line);
2453 			continue;
2454 		    } else {
2455 			Parse_Error (PARSE_FATAL,
2456 				     "Unassociated shell command \"%.20s\"",
2457 				     cp);
2458 		    }
2459 		}
2460 #ifdef SYSVINCLUDE
2461 	    } else if (strncmp (line, "include", 7) == 0 &&
2462 		       strchr(line, ':') == NULL) {
2463 		/*
2464 		 * It's an S3/S5-style "include".
2465 		 */
2466 		ParseTraditionalInclude (line + 7);
2467 		goto nextLine;
2468 #endif
2469 	    } else if (Parse_IsVar (line)) {
2470 		ParseFinishLine();
2471 		Parse_DoVar (line, VAR_GLOBAL);
2472 	    } else {
2473 		/*
2474 		 * We now know it's a dependency line so it needs to have all
2475 		 * variables expanded before being parsed. Tell the variable
2476 		 * module to complain if some variable is undefined...
2477 		 * To make life easier on novices, if the line is indented we
2478 		 * first make sure the line has a dependency operator in it.
2479 		 * If it doesn't have an operator and we're in a dependency
2480 		 * line's script, we assume it's actually a shell command
2481 		 * and add it to the current list of targets.
2482 		 */
2483 #ifndef POSIX
2484 		Boolean	nonSpace = FALSE;
2485 #endif
2486 
2487 		cp = line;
2488 		if (isspace((unsigned char) line[0])) {
2489 		    while ((*cp != '\0') && isspace((unsigned char) *cp)) {
2490 			cp++;
2491 		    }
2492 		    if (*cp == '\0') {
2493 			goto nextLine;
2494 		    }
2495 #ifndef POSIX
2496 		    while ((*cp != ':') && (*cp != '!') && (*cp != '\0')) {
2497 			nonSpace = TRUE;
2498 			cp++;
2499 		    }
2500 #endif
2501 		}
2502 
2503 #ifndef POSIX
2504 		if (*cp == '\0') {
2505 		    if (inLine) {
2506 			Parse_Error (PARSE_WARNING,
2507 				     "Shell command needs a leading tab");
2508 			goto shellCommand;
2509 		    } else if (nonSpace) {
2510 			Parse_Error (PARSE_FATAL, "Missing operator");
2511 		    }
2512 		} else {
2513 #endif
2514 		    ParseFinishLine();
2515 
2516 		    cp = Var_Subst (NULL, line, VAR_CMD, TRUE);
2517 		    free (line);
2518 		    line = cp;
2519 
2520 		    /*
2521 		     * Need a non-circular list for the target nodes
2522 		     */
2523 		    if (targets)
2524 			Lst_Destroy(targets, NOFREE);
2525 
2526 		    targets = Lst_Init (FALSE);
2527 		    inLine = TRUE;
2528 
2529 		    ParseDoDependency (line);
2530 #ifndef POSIX
2531 		}
2532 #endif
2533 	    }
2534 
2535 	    nextLine:
2536 
2537 	    free (line);
2538 	}
2539 	/*
2540 	 * Reached EOF, but it may be just EOF of an include file...
2541 	 */
2542     } while (ParseEOF(1) == CONTINUE);
2543 
2544     /*
2545      * Make sure conditionals are clean
2546      */
2547     Cond_End();
2548 
2549     if (fatals) {
2550 	fprintf (stderr, "Fatal errors encountered -- cannot continue\n");
2551 	exit (1);
2552     }
2553 }
2554 
2555 /*-
2556  *---------------------------------------------------------------------
2557  * Parse_Init --
2558  *	initialize the parsing module
2559  *
2560  * Results:
2561  *	none
2562  *
2563  * Side Effects:
2564  *	the parseIncPath list is initialized...
2565  *---------------------------------------------------------------------
2566  */
2567 void
2568 Parse_Init ()
2569 {
2570 	char *cp = NULL, *start;
2571 					/* avoid faults on read-only strings */
2572 	static char syspath[] = _PATH_DEFSYSPATH;
2573 
2574     mainNode = NILGNODE;
2575     parseIncPath = Lst_Init (FALSE);
2576     sysIncPath = Lst_Init (FALSE);
2577     includes = Lst_Init (FALSE);
2578     targCmds = Lst_Init (FALSE);
2579 
2580     /*
2581      * Add the directories from the DEFSYSPATH (more than one may be given
2582      * as dir1:...:dirn) to the system include path.
2583      */
2584     for (start = syspath; *start != '\0'; start = cp) {
2585 	for (cp = start; *cp != '\0' && *cp != ':'; cp++)
2586 	    continue;
2587 	if (*cp == '\0') {
2588 	    Dir_AddDir(sysIncPath, start);
2589 	} else {
2590 	    *cp++ = '\0';
2591 	    Dir_AddDir(sysIncPath, start);
2592 	}
2593     }
2594 }
2595 
2596 void
2597 Parse_End()
2598 {
2599     Lst_Destroy(targCmds, (void (*) __P((ClientData))) free);
2600     if (targets)
2601 	Lst_Destroy(targets, NOFREE);
2602     Lst_Destroy(sysIncPath, Dir_Destroy);
2603     Lst_Destroy(parseIncPath, Dir_Destroy);
2604     Lst_Destroy(includes, NOFREE);	/* Should be empty now */
2605 }
2606 
2607 
2608 /*-
2609  *-----------------------------------------------------------------------
2610  * Parse_MainName --
2611  *	Return a Lst of the main target to create for main()'s sake. If
2612  *	no such target exists, we Punt with an obnoxious error message.
2613  *
2614  * Results:
2615  *	A Lst of the single node to create.
2616  *
2617  * Side Effects:
2618  *	None.
2619  *
2620  *-----------------------------------------------------------------------
2621  */
2622 Lst
2623 Parse_MainName()
2624 {
2625     Lst           main;	/* result list */
2626 
2627     main = Lst_Init (FALSE);
2628 
2629     if (mainNode == NILGNODE) {
2630 	Punt ("make: no target to make.\n");
2631     	/*NOTREACHED*/
2632     } else if (mainNode->type & OP_DOUBLEDEP) {
2633 	(void) Lst_AtEnd (main, (ClientData)mainNode);
2634 	Lst_Concat(main, mainNode->cohorts, LST_CONCNEW);
2635     }
2636     else
2637 	(void) Lst_AtEnd (main, (ClientData)mainNode);
2638     return (main);
2639 }
2640