xref: /freebsd/contrib/bmake/parse.c (revision 454630c72556d45e401f29f56b3317c2fb0499a0)
1 /*	$NetBSD: parse.c,v 1.668 2022/03/25 21:16:04 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 /*
72  * Parsing of makefiles.
73  *
74  * Parse_File is the main entry point and controls most of the other
75  * functions in this module.
76  *
77  * Interface:
78  *	Parse_Init	Initialize the module
79  *
80  *	Parse_End	Clean up the module
81  *
82  *	Parse_File	Parse a top-level makefile.  Included files are
83  *			handled by IncludeFile instead.
84  *
85  *	Parse_VarAssign
86  *			Try to parse the given line as a variable assignment.
87  *			Used by MainParseArgs to determine if an argument is
88  *			a target or a variable assignment.  Used internally
89  *			for pretty much the same thing.
90  *
91  *	Parse_Error	Report a parse error, a warning or an informational
92  *			message.
93  *
94  *	Parse_MainName	Returns a list of the single main target to create.
95  */
96 
97 #include <sys/types.h>
98 #include <sys/stat.h>
99 #include <errno.h>
100 #include <stdarg.h>
101 
102 #include "make.h"
103 
104 #ifdef HAVE_STDINT_H
105 #include <stdint.h>
106 #endif
107 
108 #ifdef HAVE_MMAP
109 #include <sys/mman.h>
110 
111 #ifndef MAP_COPY
112 #define MAP_COPY MAP_PRIVATE
113 #endif
114 #ifndef MAP_FILE
115 #define MAP_FILE 0
116 #endif
117 #endif
118 
119 #include "dir.h"
120 #include "job.h"
121 #include "pathnames.h"
122 
123 /*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
124 MAKE_RCSID("$NetBSD: parse.c,v 1.668 2022/03/25 21:16:04 sjg Exp $");
125 
126 /*
127  * A file being read.
128  */
129 typedef struct IncludedFile {
130 	FStr name;		/* absolute or relative to the cwd */
131 	unsigned lineno;	/* 1-based */
132 	unsigned readLines;	/* the number of physical lines that have
133 				 * been read from the file */
134 	unsigned forHeadLineno;	/* 1-based */
135 	unsigned forBodyReadLines; /* the number of physical lines that have
136 				 * been read from the file above the body of
137 				 * the .for loop */
138 	unsigned int cond_depth; /* 'if' nesting when file opened */
139 	bool depending;		/* state of doing_depend on EOF */
140 
141 	Buffer buf;		/* the file's content or the body of the .for
142 				 * loop; either empty or ends with '\n' */
143 	char *buf_ptr;		/* next char to be read */
144 	char *buf_end;		/* buf_end[-1] == '\n' */
145 
146 	struct ForLoop *forLoop;
147 } IncludedFile;
148 
149 /* Special attributes for target nodes. */
150 typedef enum ParseSpecial {
151 	SP_ATTRIBUTE,	/* Generic attribute */
152 	SP_BEGIN,	/* .BEGIN */
153 	SP_DEFAULT,	/* .DEFAULT */
154 	SP_DELETE_ON_ERROR, /* .DELETE_ON_ERROR */
155 	SP_END,		/* .END */
156 	SP_ERROR,	/* .ERROR */
157 	SP_IGNORE,	/* .IGNORE */
158 	SP_INCLUDES,	/* .INCLUDES; not mentioned in the manual page */
159 	SP_INTERRUPT,	/* .INTERRUPT */
160 	SP_LIBS,	/* .LIBS; not mentioned in the manual page */
161 	SP_MAIN,	/* .MAIN and no user-specified targets to make */
162 	SP_META,	/* .META */
163 	SP_MFLAGS,	/* .MFLAGS or .MAKEFLAGS */
164 	SP_NOMETA,	/* .NOMETA */
165 	SP_NOMETA_CMP,	/* .NOMETA_CMP */
166 	SP_NOPATH,	/* .NOPATH */
167 	SP_NOT,		/* Not special */
168 	SP_NOTPARALLEL,	/* .NOTPARALLEL or .NO_PARALLEL */
169 	SP_NULL,	/* .NULL; not mentioned in the manual page */
170 	SP_OBJDIR,	/* .OBJDIR */
171 	SP_ORDER,	/* .ORDER */
172 	SP_PARALLEL,	/* .PARALLEL; not mentioned in the manual page */
173 	SP_PATH,	/* .PATH or .PATH.suffix */
174 	SP_PHONY,	/* .PHONY */
175 #ifdef POSIX
176 	SP_POSIX,	/* .POSIX; not mentioned in the manual page */
177 #endif
178 	SP_PRECIOUS,	/* .PRECIOUS */
179 	SP_SHELL,	/* .SHELL */
180 	SP_SILENT,	/* .SILENT */
181 	SP_SINGLESHELL,	/* .SINGLESHELL; not mentioned in the manual page */
182 	SP_STALE,	/* .STALE */
183 	SP_SUFFIXES,	/* .SUFFIXES */
184 	SP_WAIT		/* .WAIT */
185 } ParseSpecial;
186 
187 typedef List SearchPathList;
188 typedef ListNode SearchPathListNode;
189 
190 
191 typedef enum VarAssignOp {
192 	VAR_NORMAL,		/* = */
193 	VAR_APPEND,		/* += */
194 	VAR_DEFAULT,		/* ?= */
195 	VAR_SUBST,		/* := */
196 	VAR_SHELL		/* != or :sh= */
197 } VarAssignOp;
198 
199 typedef struct VarAssign {
200 	char *varname;		/* unexpanded */
201 	VarAssignOp op;
202 	const char *value;	/* unexpanded */
203 } VarAssign;
204 
205 static bool Parse_IsVar(const char *, VarAssign *);
206 static void Parse_Var(VarAssign *, GNode *);
207 
208 /*
209  * The target to be made if no targets are specified in the command line.
210  * This is the first target defined in any of the makefiles.
211  */
212 GNode *mainNode;
213 
214 /*
215  * During parsing, the targets from the left-hand side of the currently
216  * active dependency line, or NULL if the current line does not belong to a
217  * dependency line, for example because it is a variable assignment.
218  *
219  * See unit-tests/deptgt.mk, keyword "parse.c:targets".
220  */
221 static GNodeList *targets;
222 
223 #ifdef CLEANUP
224 /*
225  * All shell commands for all targets, in no particular order and possibly
226  * with duplicates.  Kept in a separate list since the commands from .USE or
227  * .USEBEFORE nodes are shared with other GNodes, thereby giving up the
228  * easily understandable ownership over the allocated strings.
229  */
230 static StringList targCmds = LST_INIT;
231 #endif
232 
233 /*
234  * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
235  * is seen, then set to each successive source on the line.
236  */
237 static GNode *order_pred;
238 
239 static int parseErrors = 0;
240 
241 /*
242  * The include chain of makefiles.  At index 0 is the top-level makefile from
243  * the command line, followed by the included files or .for loops, up to and
244  * including the current file.
245  *
246  * See PrintStackTrace for how to interpret the data.
247  */
248 static Vector /* of IncludedFile */ includes;
249 
250 SearchPath *parseIncPath;	/* directories for "..." includes */
251 SearchPath *sysIncPath;		/* directories for <...> includes */
252 SearchPath *defSysIncPath;	/* default for sysIncPath */
253 
254 /*
255  * The parseKeywords table is searched using binary search when deciding
256  * if a target or source is special. The 'spec' field is the ParseSpecial
257  * type of the keyword (SP_NOT if the keyword isn't special as a target) while
258  * the 'op' field is the operator to apply to the list of targets if the
259  * keyword is used as a source ("0" if the keyword isn't special as a source)
260  */
261 static const struct {
262 	const char name[17];
263 	ParseSpecial special;	/* when used as a target */
264 	GNodeType targetAttr;	/* when used as a source */
265 } parseKeywords[] = {
266     { ".BEGIN",		SP_BEGIN,	OP_NONE },
267     { ".DEFAULT",	SP_DEFAULT,	OP_NONE },
268     { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, OP_NONE },
269     { ".END",		SP_END,		OP_NONE },
270     { ".ERROR",		SP_ERROR,	OP_NONE },
271     { ".EXEC",		SP_ATTRIBUTE,	OP_EXEC },
272     { ".IGNORE",	SP_IGNORE,	OP_IGNORE },
273     { ".INCLUDES",	SP_INCLUDES,	OP_NONE },
274     { ".INTERRUPT",	SP_INTERRUPT,	OP_NONE },
275     { ".INVISIBLE",	SP_ATTRIBUTE,	OP_INVISIBLE },
276     { ".JOIN",		SP_ATTRIBUTE,	OP_JOIN },
277     { ".LIBS",		SP_LIBS,	OP_NONE },
278     { ".MADE",		SP_ATTRIBUTE,	OP_MADE },
279     { ".MAIN",		SP_MAIN,	OP_NONE },
280     { ".MAKE",		SP_ATTRIBUTE,	OP_MAKE },
281     { ".MAKEFLAGS",	SP_MFLAGS,	OP_NONE },
282     { ".META",		SP_META,	OP_META },
283     { ".MFLAGS",	SP_MFLAGS,	OP_NONE },
284     { ".NOMETA",	SP_NOMETA,	OP_NOMETA },
285     { ".NOMETA_CMP",	SP_NOMETA_CMP,	OP_NOMETA_CMP },
286     { ".NOPATH",	SP_NOPATH,	OP_NOPATH },
287     { ".NOTMAIN",	SP_ATTRIBUTE,	OP_NOTMAIN },
288     { ".NOTPARALLEL",	SP_NOTPARALLEL,	OP_NONE },
289     { ".NO_PARALLEL",	SP_NOTPARALLEL,	OP_NONE },
290     { ".NULL",		SP_NULL,	OP_NONE },
291     { ".OBJDIR",	SP_OBJDIR,	OP_NONE },
292     { ".OPTIONAL",	SP_ATTRIBUTE,	OP_OPTIONAL },
293     { ".ORDER",		SP_ORDER,	OP_NONE },
294     { ".PARALLEL",	SP_PARALLEL,	OP_NONE },
295     { ".PATH",		SP_PATH,	OP_NONE },
296     { ".PHONY",		SP_PHONY,	OP_PHONY },
297 #ifdef POSIX
298     { ".POSIX",		SP_POSIX,	OP_NONE },
299 #endif
300     { ".PRECIOUS",	SP_PRECIOUS,	OP_PRECIOUS },
301     { ".RECURSIVE",	SP_ATTRIBUTE,	OP_MAKE },
302     { ".SHELL",		SP_SHELL,	OP_NONE },
303     { ".SILENT",	SP_SILENT,	OP_SILENT },
304     { ".SINGLESHELL",	SP_SINGLESHELL,	OP_NONE },
305     { ".STALE",		SP_STALE,	OP_NONE },
306     { ".SUFFIXES",	SP_SUFFIXES,	OP_NONE },
307     { ".USE",		SP_ATTRIBUTE,	OP_USE },
308     { ".USEBEFORE",	SP_ATTRIBUTE,	OP_USEBEFORE },
309     { ".WAIT",		SP_WAIT,	OP_NONE },
310 };
311 
312 
313 static IncludedFile *
314 GetInclude(size_t i)
315 {
316 	return Vector_Get(&includes, i);
317 }
318 
319 /* The file that is currently being read. */
320 static IncludedFile *
321 CurFile(void)
322 {
323 	return GetInclude(includes.len - 1);
324 }
325 
326 static Buffer
327 loadfile(const char *path, int fd)
328 {
329 	ssize_t n;
330 	Buffer buf;
331 	size_t bufSize;
332 	struct stat st;
333 
334 	bufSize = fstat(fd, &st) == 0 && S_ISREG(st.st_mode) &&
335 		  st.st_size > 0 && st.st_size < 1024 * 1024 * 1024
336 	    ? (size_t)st.st_size : 1024;
337 	Buf_InitSize(&buf, bufSize);
338 
339 	for (;;) {
340 		if (buf.len == buf.cap) {
341 			if (buf.cap >= 512 * 1024 * 1024) {
342 				Error("%s: file too large", path);
343 				exit(2); /* Not 1 so -q can distinguish error */
344 			}
345 			Buf_Expand(&buf);
346 		}
347 		assert(buf.len < buf.cap);
348 		n = read(fd, buf.data + buf.len, buf.cap - buf.len);
349 		if (n < 0) {
350 			Error("%s: read error: %s", path, strerror(errno));
351 			exit(2);	/* Not 1 so -q can distinguish error */
352 		}
353 		if (n == 0)
354 			break;
355 
356 		buf.len += (size_t)n;
357 	}
358 	assert(buf.len <= buf.cap);
359 
360 	if (!Buf_EndsWith(&buf, '\n'))
361 		Buf_AddByte(&buf, '\n');
362 
363 	return buf;		/* may not be null-terminated */
364 }
365 
366 /*
367  * Print the current chain of .include and .for directives.  In Parse_Fatal
368  * or other functions that already print the location, includingInnermost
369  * would be redundant, but in other cases like Error or Fatal it needs to be
370  * included.
371  */
372 void
373 PrintStackTrace(bool includingInnermost)
374 {
375 	const IncludedFile *entries;
376 	size_t i, n;
377 
378 	entries = GetInclude(0);
379 	n = includes.len;
380 	if (n == 0)
381 		return;
382 
383 	if (!includingInnermost && entries[n - 1].forLoop == NULL)
384 		n--;		/* already in the diagnostic */
385 
386 	for (i = n; i-- > 0;) {
387 		const IncludedFile *entry = entries + i;
388 		const char *fname = entry->name.str;
389 		char dirbuf[MAXPATHLEN + 1];
390 
391 		if (fname[0] != '/' && strcmp(fname, "(stdin)") != 0)
392 			fname = realpath(fname, dirbuf);
393 
394 		if (entry->forLoop != NULL) {
395 			char *details = ForLoop_Details(entry->forLoop);
396 			debug_printf("\tin .for loop from %s:%u with %s\n",
397 			    fname, entry->forHeadLineno, details);
398 			free(details);
399 		} else if (i + 1 < n && entries[i + 1].forLoop != NULL) {
400 			/* entry->lineno is not a useful line number */
401 		} else
402 			debug_printf("\tin %s:%u\n", fname, entry->lineno);
403 	}
404 }
405 
406 /* Check if the current character is escaped on the current line. */
407 static bool
408 IsEscaped(const char *line, const char *p)
409 {
410 	bool escaped = false;
411 	while (p > line && *--p == '\\')
412 		escaped = !escaped;
413 	return escaped;
414 }
415 
416 /*
417  * Add the filename and lineno to the GNode so that we remember where it
418  * was first defined.
419  */
420 static void
421 RememberLocation(GNode *gn)
422 {
423 	IncludedFile *curFile = CurFile();
424 	gn->fname = Str_Intern(curFile->name.str);
425 	gn->lineno = curFile->lineno;
426 }
427 
428 /*
429  * Look in the table of keywords for one matching the given string.
430  * Return the index of the keyword, or -1 if it isn't there.
431  */
432 static int
433 FindKeyword(const char *str)
434 {
435 	int start = 0;
436 	int end = sizeof parseKeywords / sizeof parseKeywords[0] - 1;
437 
438 	while (start <= end) {
439 		int curr = start + (end - start) / 2;
440 		int diff = strcmp(str, parseKeywords[curr].name);
441 
442 		if (diff == 0)
443 			return curr;
444 		if (diff < 0)
445 			end = curr - 1;
446 		else
447 			start = curr + 1;
448 	}
449 
450 	return -1;
451 }
452 
453 void
454 PrintLocation(FILE *f, bool useVars, const char *fname, unsigned lineno)
455 {
456 	char dirbuf[MAXPATHLEN + 1];
457 	FStr dir, base;
458 
459 	if (!useVars || fname[0] == '/' || strcmp(fname, "(stdin)") == 0) {
460 		(void)fprintf(f, "\"%s\" line %u: ", fname, lineno);
461 		return;
462 	}
463 
464 	dir = Var_Value(SCOPE_GLOBAL, ".PARSEDIR");
465 	if (dir.str == NULL)
466 		dir.str = ".";
467 	if (dir.str[0] != '/')
468 		dir.str = realpath(dir.str, dirbuf);
469 
470 	base = Var_Value(SCOPE_GLOBAL, ".PARSEFILE");
471 	if (base.str == NULL)
472 		base.str = str_basename(fname);
473 
474 	(void)fprintf(f, "\"%s/%s\" line %u: ", dir.str, base.str, lineno);
475 
476 	FStr_Done(&base);
477 	FStr_Done(&dir);
478 }
479 
480 static void MAKE_ATTR_PRINTFLIKE(6, 0)
481 ParseVErrorInternal(FILE *f, bool useVars, const char *fname, unsigned lineno,
482 		    ParseErrorLevel level, const char *fmt, va_list ap)
483 {
484 	static bool fatal_warning_error_printed = false;
485 
486 	(void)fprintf(f, "%s: ", progname);
487 
488 	if (fname != NULL)
489 		PrintLocation(f, useVars, fname, lineno);
490 	if (level == PARSE_WARNING)
491 		(void)fprintf(f, "warning: ");
492 	(void)vfprintf(f, fmt, ap);
493 	(void)fprintf(f, "\n");
494 	(void)fflush(f);
495 
496 	if (level == PARSE_FATAL)
497 		parseErrors++;
498 	if (level == PARSE_WARNING && opts.parseWarnFatal) {
499 		if (!fatal_warning_error_printed) {
500 			Error("parsing warnings being treated as errors");
501 			fatal_warning_error_printed = true;
502 		}
503 		parseErrors++;
504 	}
505 
506 	if (DEBUG(PARSE))
507 		PrintStackTrace(false);
508 }
509 
510 static void MAKE_ATTR_PRINTFLIKE(4, 5)
511 ParseErrorInternal(const char *fname, unsigned lineno,
512 		   ParseErrorLevel level, const char *fmt, ...)
513 {
514 	va_list ap;
515 
516 	(void)fflush(stdout);
517 	va_start(ap, fmt);
518 	ParseVErrorInternal(stderr, false, fname, lineno, level, fmt, ap);
519 	va_end(ap);
520 
521 	if (opts.debug_file != stdout && opts.debug_file != stderr) {
522 		va_start(ap, fmt);
523 		ParseVErrorInternal(opts.debug_file, false, fname, lineno,
524 		    level, fmt, ap);
525 		va_end(ap);
526 	}
527 }
528 
529 /*
530  * Print a parse error message, including location information.
531  *
532  * If the level is PARSE_FATAL, continue parsing until the end of the
533  * current top-level makefile, then exit (see Parse_File).
534  *
535  * Fmt is given without a trailing newline.
536  */
537 void
538 Parse_Error(ParseErrorLevel level, const char *fmt, ...)
539 {
540 	va_list ap;
541 	const char *fname;
542 	unsigned lineno;
543 
544 	if (includes.len == 0) {
545 		fname = NULL;
546 		lineno = 0;
547 	} else {
548 		IncludedFile *curFile = CurFile();
549 		fname = curFile->name.str;
550 		lineno = curFile->lineno;
551 	}
552 
553 	(void)fflush(stdout);
554 	va_start(ap, fmt);
555 	ParseVErrorInternal(stderr, true, fname, lineno, level, fmt, ap);
556 	va_end(ap);
557 
558 	if (opts.debug_file != stdout && opts.debug_file != stderr) {
559 		va_start(ap, fmt);
560 		ParseVErrorInternal(opts.debug_file, true, fname, lineno,
561 		    level, fmt, ap);
562 		va_end(ap);
563 	}
564 }
565 
566 
567 /*
568  * Handle an .info, .warning or .error directive.  For an .error directive,
569  * exit immediately.
570  */
571 static void
572 HandleMessage(ParseErrorLevel level, const char *levelName, const char *umsg)
573 {
574 	char *xmsg;
575 
576 	if (umsg[0] == '\0') {
577 		Parse_Error(PARSE_FATAL, "Missing argument for \".%s\"",
578 		    levelName);
579 		return;
580 	}
581 
582 	(void)Var_Subst(umsg, SCOPE_CMDLINE, VARE_WANTRES, &xmsg);
583 	/* TODO: handle errors */
584 
585 	Parse_Error(level, "%s", xmsg);
586 	free(xmsg);
587 
588 	if (level == PARSE_FATAL) {
589 		PrintOnError(NULL, "\n");
590 		exit(1);
591 	}
592 }
593 
594 /*
595  * Add the child to the parent's children, and for non-special targets, vice
596  * versa.  Special targets such as .END do not need to be informed once the
597  * child target has been made.
598  */
599 static void
600 LinkSource(GNode *pgn, GNode *cgn, bool isSpecial)
601 {
602 	if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(&pgn->cohorts))
603 		pgn = pgn->cohorts.last->datum;
604 
605 	Lst_Append(&pgn->children, cgn);
606 	pgn->unmade++;
607 
608 	/* Special targets like .END don't need any children. */
609 	if (!isSpecial)
610 		Lst_Append(&cgn->parents, pgn);
611 
612 	if (DEBUG(PARSE)) {
613 		debug_printf("# LinkSource: added child %s - %s\n",
614 		    pgn->name, cgn->name);
615 		Targ_PrintNode(pgn, 0);
616 		Targ_PrintNode(cgn, 0);
617 	}
618 }
619 
620 /* Add the node to each target from the current dependency group. */
621 static void
622 LinkToTargets(GNode *gn, bool isSpecial)
623 {
624 	GNodeListNode *ln;
625 
626 	for (ln = targets->first; ln != NULL; ln = ln->next)
627 		LinkSource(ln->datum, gn, isSpecial);
628 }
629 
630 static bool
631 TryApplyDependencyOperator(GNode *gn, GNodeType op)
632 {
633 	/*
634 	 * If the node occurred on the left-hand side of a dependency and the
635 	 * operator also defines a dependency, they must match.
636 	 */
637 	if ((op & OP_OPMASK) && (gn->type & OP_OPMASK) &&
638 	    ((op & OP_OPMASK) != (gn->type & OP_OPMASK))) {
639 		Parse_Error(PARSE_FATAL, "Inconsistent operator for %s",
640 		    gn->name);
641 		return false;
642 	}
643 
644 	if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
645 		/*
646 		 * If the node was of the left-hand side of a '::' operator,
647 		 * we need to create a new instance of it for the children
648 		 * and commands on this dependency line since each of these
649 		 * dependency groups has its own attributes and commands,
650 		 * separate from the others.
651 		 *
652 		 * The new instance is placed on the 'cohorts' list of the
653 		 * initial one (note the initial one is not on its own
654 		 * cohorts list) and the new instance is linked to all
655 		 * parents of the initial instance.
656 		 */
657 		GNode *cohort;
658 
659 		/*
660 		 * Propagate copied bits to the initial node.  They'll be
661 		 * propagated back to the rest of the cohorts later.
662 		 */
663 		gn->type |= op & ~OP_OPMASK;
664 
665 		cohort = Targ_NewInternalNode(gn->name);
666 		if (doing_depend)
667 			RememberLocation(cohort);
668 		/*
669 		 * Make the cohort invisible as well to avoid duplicating it
670 		 * into other variables. True, parents of this target won't
671 		 * tend to do anything with their local variables, but better
672 		 * safe than sorry.
673 		 *
674 		 * (I think this is pointless now, since the relevant list
675 		 * traversals will no longer see this node anyway. -mycroft)
676 		 */
677 		cohort->type = op | OP_INVISIBLE;
678 		Lst_Append(&gn->cohorts, cohort);
679 		cohort->centurion = gn;
680 		gn->unmade_cohorts++;
681 		snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
682 		    (unsigned int)gn->unmade_cohorts % 1000000);
683 	} else {
684 		/*
685 		 * We don't want to nuke any previous flags (whatever they
686 		 * were) so we just OR the new operator into the old.
687 		 */
688 		gn->type |= op;
689 	}
690 
691 	return true;
692 }
693 
694 static void
695 ApplyDependencyOperator(GNodeType op)
696 {
697 	GNodeListNode *ln;
698 
699 	for (ln = targets->first; ln != NULL; ln = ln->next)
700 		if (!TryApplyDependencyOperator(ln->datum, op))
701 			break;
702 }
703 
704 /*
705  * We add a .WAIT node in the dependency list. After any dynamic dependencies
706  * (and filename globbing) have happened, it is given a dependency on each
707  * previous child, back until the previous .WAIT node. The next child won't
708  * be scheduled until the .WAIT node is built.
709  *
710  * We give each .WAIT node a unique name (mainly for diagnostics).
711  */
712 static void
713 ApplyDependencySourceWait(bool isSpecial)
714 {
715 	static unsigned wait_number = 0;
716 	char wait_src[16];
717 	GNode *gn;
718 
719 	snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
720 	gn = Targ_NewInternalNode(wait_src);
721 	if (doing_depend)
722 		RememberLocation(gn);
723 	gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
724 	LinkToTargets(gn, isSpecial);
725 }
726 
727 static bool
728 ApplyDependencySourceKeyword(const char *src, ParseSpecial special)
729 {
730 	int keywd;
731 	GNodeType targetAttr;
732 
733 	if (*src != '.' || !ch_isupper(src[1]))
734 		return false;
735 
736 	keywd = FindKeyword(src);
737 	if (keywd == -1)
738 		return false;
739 
740 	targetAttr = parseKeywords[keywd].targetAttr;
741 	if (targetAttr != OP_NONE) {
742 		ApplyDependencyOperator(targetAttr);
743 		return true;
744 	}
745 	if (parseKeywords[keywd].special == SP_WAIT) {
746 		ApplyDependencySourceWait(special != SP_NOT);
747 		return true;
748 	}
749 	return false;
750 }
751 
752 /*
753  * In a line like ".MAIN: source1 source2", add all sources to the list of
754  * things to create, but only if the user didn't specify a target on the
755  * command line and .MAIN occurs for the first time.
756  *
757  * See HandleDependencyTargetSpecial, branch SP_MAIN.
758  * See unit-tests/cond-func-make-main.mk.
759  */
760 static void
761 ApplyDependencySourceMain(const char *src)
762 {
763 	Lst_Append(&opts.create, bmake_strdup(src));
764 	/*
765 	 * Add the name to the .TARGETS variable as well, so the user can
766 	 * employ that, if desired.
767 	 */
768 	Global_Append(".TARGETS", src);
769 }
770 
771 /*
772  * For the sources of a .ORDER target, create predecessor/successor links
773  * between the previous source and the current one.
774  */
775 static void
776 ApplyDependencySourceOrder(const char *src)
777 {
778 	GNode *gn;
779 
780 	gn = Targ_GetNode(src);
781 	if (doing_depend)
782 		RememberLocation(gn);
783 	if (order_pred != NULL) {
784 		Lst_Append(&order_pred->order_succ, gn);
785 		Lst_Append(&gn->order_pred, order_pred);
786 		if (DEBUG(PARSE)) {
787 			debug_printf(
788 			    "# .ORDER forces '%s' to be made before '%s'\n",
789 			    order_pred->name, gn->name);
790 			Targ_PrintNode(order_pred, 0);
791 			Targ_PrintNode(gn, 0);
792 		}
793 	}
794 	/*
795 	 * The current source now becomes the predecessor for the next one.
796 	 */
797 	order_pred = gn;
798 }
799 
800 /* The source is not an attribute, so find/create a node for it. */
801 static void
802 ApplyDependencySourceOther(const char *src, GNodeType targetAttr,
803 			   ParseSpecial special)
804 {
805 	GNode *gn;
806 
807 	gn = Targ_GetNode(src);
808 	if (doing_depend)
809 		RememberLocation(gn);
810 	if (targetAttr != OP_NONE)
811 		gn->type |= targetAttr;
812 	else
813 		LinkToTargets(gn, special != SP_NOT);
814 }
815 
816 /*
817  * Given the name of a source in a dependency line, figure out if it is an
818  * attribute (such as .SILENT) and if so, apply it to all targets. Otherwise
819  * decide if there is some attribute which should be applied *to* the source
820  * because of some special target (such as .PHONY) and apply it if so.
821  * Otherwise, make the source a child of the targets.
822  */
823 static void
824 ApplyDependencySource(GNodeType targetAttr, const char *src,
825 		      ParseSpecial special)
826 {
827 	if (ApplyDependencySourceKeyword(src, special))
828 		return;
829 
830 	if (special == SP_MAIN)
831 		ApplyDependencySourceMain(src);
832 	else if (special == SP_ORDER)
833 		ApplyDependencySourceOrder(src);
834 	else
835 		ApplyDependencySourceOther(src, targetAttr, special);
836 }
837 
838 /*
839  * If we have yet to decide on a main target to make, in the absence of any
840  * user input, we want the first target on the first dependency line that is
841  * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made.
842  */
843 static void
844 MaybeUpdateMainTarget(void)
845 {
846 	GNodeListNode *ln;
847 
848 	if (mainNode != NULL)
849 		return;
850 
851 	for (ln = targets->first; ln != NULL; ln = ln->next) {
852 		GNode *gn = ln->datum;
853 		if (GNode_IsMainCandidate(gn)) {
854 			DEBUG1(MAKE, "Setting main node to \"%s\"\n", gn->name);
855 			mainNode = gn;
856 			return;
857 		}
858 	}
859 }
860 
861 static void
862 InvalidLineType(const char *line)
863 {
864 	if (strncmp(line, "<<<<<<", 6) == 0 ||
865 	    strncmp(line, ">>>>>>", 6) == 0)
866 		Parse_Error(PARSE_FATAL,
867 		    "Makefile appears to contain unresolved CVS/RCS/??? merge conflicts");
868 	else if (line[0] == '.') {
869 		const char *dirstart = line + 1;
870 		const char *dirend;
871 		cpp_skip_whitespace(&dirstart);
872 		dirend = dirstart;
873 		while (ch_isalnum(*dirend) || *dirend == '-')
874 			dirend++;
875 		Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
876 		    (int)(dirend - dirstart), dirstart);
877 	} else
878 		Parse_Error(PARSE_FATAL, "Invalid line type");
879 }
880 
881 static void
882 ParseDependencyTargetWord(char **pp, const char *lstart)
883 {
884 	const char *cp = *pp;
885 
886 	while (*cp != '\0') {
887 		if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' ||
888 		     *cp == '(') &&
889 		    !IsEscaped(lstart, cp))
890 			break;
891 
892 		if (*cp == '$') {
893 			/*
894 			 * Must be a dynamic source (would have been expanded
895 			 * otherwise).
896 			 *
897 			 * There should be no errors in this, as they would
898 			 * have been discovered in the initial Var_Subst and
899 			 * we wouldn't be here.
900 			 */
901 			FStr val;
902 
903 			(void)Var_Parse(&cp, SCOPE_CMDLINE,
904 			    VARE_PARSE_ONLY, &val);
905 			FStr_Done(&val);
906 		} else
907 			cp++;
908 	}
909 
910 	*pp += cp - *pp;
911 }
912 
913 /*
914  * Handle special targets like .PATH, .DEFAULT, .BEGIN, .ORDER.
915  *
916  * See the tests deptgt-*.mk.
917  */
918 static void
919 HandleDependencyTargetSpecial(const char *targetName,
920 			      ParseSpecial *inout_special,
921 			      SearchPathList **inout_paths)
922 {
923 	switch (*inout_special) {
924 	case SP_PATH:
925 		if (*inout_paths == NULL)
926 			*inout_paths = Lst_New();
927 		Lst_Append(*inout_paths, &dirSearchPath);
928 		break;
929 	case SP_MAIN:
930 		/*
931 		 * Allow targets from the command line to override the
932 		 * .MAIN node.
933 		 */
934 		if (!Lst_IsEmpty(&opts.create))
935 			*inout_special = SP_NOT;
936 		break;
937 	case SP_BEGIN:
938 	case SP_END:
939 	case SP_STALE:
940 	case SP_ERROR:
941 	case SP_INTERRUPT: {
942 		GNode *gn = Targ_GetNode(targetName);
943 		if (doing_depend)
944 			RememberLocation(gn);
945 		gn->type |= OP_NOTMAIN | OP_SPECIAL;
946 		Lst_Append(targets, gn);
947 		break;
948 	}
949 	case SP_DEFAULT: {
950 		/*
951 		 * Need to create a node to hang commands on, but we don't
952 		 * want it in the graph, nor do we want it to be the Main
953 		 * Target. We claim the node is a transformation rule to make
954 		 * life easier later, when we'll use Make_HandleUse to
955 		 * actually apply the .DEFAULT commands.
956 		 */
957 		GNode *gn = GNode_New(".DEFAULT");
958 		gn->type |= OP_NOTMAIN | OP_TRANSFORM;
959 		Lst_Append(targets, gn);
960 		defaultNode = gn;
961 		break;
962 	}
963 	case SP_DELETE_ON_ERROR:
964 		deleteOnError = true;
965 		break;
966 	case SP_NOTPARALLEL:
967 		opts.maxJobs = 1;
968 		break;
969 	case SP_SINGLESHELL:
970 		opts.compatMake = true;
971 		break;
972 	case SP_ORDER:
973 		order_pred = NULL;
974 		break;
975 	default:
976 		break;
977 	}
978 }
979 
980 static bool
981 HandleDependencyTargetPath(const char *suffixName,
982 			   SearchPathList **inout_paths)
983 {
984 	SearchPath *path;
985 
986 	path = Suff_GetPath(suffixName);
987 	if (path == NULL) {
988 		Parse_Error(PARSE_FATAL,
989 		    "Suffix '%s' not defined (yet)", suffixName);
990 		return false;
991 	}
992 
993 	if (*inout_paths == NULL)
994 		*inout_paths = Lst_New();
995 	Lst_Append(*inout_paths, path);
996 
997 	return true;
998 }
999 
1000 /* See if it's a special target and if so set inout_special to match it. */
1001 static bool
1002 HandleDependencyTarget(const char *targetName,
1003 		       ParseSpecial *inout_special,
1004 		       GNodeType *inout_targetAttr,
1005 		       SearchPathList **inout_paths)
1006 {
1007 	int keywd;
1008 
1009 	if (!(targetName[0] == '.' && ch_isupper(targetName[1])))
1010 		return true;
1011 
1012 	/*
1013 	 * See if the target is a special target that must have it
1014 	 * or its sources handled specially.
1015 	 */
1016 	keywd = FindKeyword(targetName);
1017 	if (keywd != -1) {
1018 		if (*inout_special == SP_PATH &&
1019 		    parseKeywords[keywd].special != SP_PATH) {
1020 			Parse_Error(PARSE_FATAL, "Mismatched special targets");
1021 			return false;
1022 		}
1023 
1024 		*inout_special = parseKeywords[keywd].special;
1025 		*inout_targetAttr = parseKeywords[keywd].targetAttr;
1026 
1027 		HandleDependencyTargetSpecial(targetName, inout_special,
1028 		    inout_paths);
1029 
1030 	} else if (strncmp(targetName, ".PATH", 5) == 0) {
1031 		*inout_special = SP_PATH;
1032 		if (!HandleDependencyTargetPath(targetName + 5, inout_paths))
1033 			return false;
1034 	}
1035 	return true;
1036 }
1037 
1038 static void
1039 HandleDependencyTargetMundane(char *targetName)
1040 {
1041 	StringList targetNames = LST_INIT;
1042 
1043 	if (Dir_HasWildcards(targetName)) {
1044 		SearchPath *emptyPath = SearchPath_New();
1045 		SearchPath_Expand(emptyPath, targetName, &targetNames);
1046 		SearchPath_Free(emptyPath);
1047 	} else
1048 		Lst_Append(&targetNames, targetName);
1049 
1050 	while (!Lst_IsEmpty(&targetNames)) {
1051 		char *targName = Lst_Dequeue(&targetNames);
1052 		GNode *gn = Suff_IsTransform(targName)
1053 		    ? Suff_AddTransform(targName)
1054 		    : Targ_GetNode(targName);
1055 		if (doing_depend)
1056 			RememberLocation(gn);
1057 
1058 		Lst_Append(targets, gn);
1059 	}
1060 }
1061 
1062 static void
1063 SkipExtraTargets(char **pp, const char *lstart)
1064 {
1065 	bool warning = false;
1066 	const char *p = *pp;
1067 
1068 	while (*p != '\0') {
1069 		if (!IsEscaped(lstart, p) && (*p == '!' || *p == ':'))
1070 			break;
1071 		if (IsEscaped(lstart, p) || (*p != ' ' && *p != '\t'))
1072 			warning = true;
1073 		p++;
1074 	}
1075 	if (warning)
1076 		Parse_Error(PARSE_WARNING, "Extra target ignored");
1077 
1078 	*pp += p - *pp;
1079 }
1080 
1081 static void
1082 CheckSpecialMundaneMixture(ParseSpecial special)
1083 {
1084 	switch (special) {
1085 	case SP_DEFAULT:
1086 	case SP_STALE:
1087 	case SP_BEGIN:
1088 	case SP_END:
1089 	case SP_ERROR:
1090 	case SP_INTERRUPT:
1091 		/*
1092 		 * These create nodes on which to hang commands, so targets
1093 		 * shouldn't be empty.
1094 		 */
1095 	case SP_NOT:
1096 		/* Nothing special here -- targets may be empty. */
1097 		break;
1098 	default:
1099 		Parse_Error(PARSE_WARNING,
1100 		    "Special and mundane targets don't mix. "
1101 		    "Mundane ones ignored");
1102 		break;
1103 	}
1104 }
1105 
1106 /*
1107  * In a dependency line like 'targets: sources' or 'targets! sources', parse
1108  * the operator ':', '::' or '!' from between the targets and the sources.
1109  */
1110 static GNodeType
1111 ParseDependencyOp(char **pp)
1112 {
1113 	if (**pp == '!')
1114 		return (*pp)++, OP_FORCE;
1115 	if ((*pp)[1] == ':')
1116 		return *pp += 2, OP_DOUBLEDEP;
1117 	else
1118 		return (*pp)++, OP_DEPENDS;
1119 }
1120 
1121 static void
1122 ClearPaths(SearchPathList *paths)
1123 {
1124 	if (paths != NULL) {
1125 		SearchPathListNode *ln;
1126 		for (ln = paths->first; ln != NULL; ln = ln->next)
1127 			SearchPath_Clear(ln->datum);
1128 	}
1129 
1130 	Dir_SetPATH();
1131 }
1132 
1133 /*
1134  * Handle one of the .[-ds]include directives by remembering the current file
1135  * and pushing the included file on the stack.  After the included file has
1136  * finished, parsing continues with the including file; see Parse_PushInput
1137  * and ParseEOF.
1138  *
1139  * System includes are looked up in sysIncPath, any other includes are looked
1140  * up in the parsedir and then in the directories specified by the -I command
1141  * line options.
1142  */
1143 static void
1144 IncludeFile(const char *file, bool isSystem, bool depinc, bool silent)
1145 {
1146 	Buffer buf;
1147 	char *fullname;		/* full pathname of file */
1148 	char *newName;
1149 	char *slash, *incdir;
1150 	int fd;
1151 	int i;
1152 
1153 	fullname = file[0] == '/' ? bmake_strdup(file) : NULL;
1154 
1155 	if (fullname == NULL && !isSystem) {
1156 		/*
1157 		 * Include files contained in double-quotes are first searched
1158 		 * relative to the including file's location. We don't want to
1159 		 * cd there, of course, so we just tack on the old file's
1160 		 * leading path components and call Dir_FindFile to see if
1161 		 * we can locate the file.
1162 		 */
1163 
1164 		incdir = bmake_strdup(CurFile()->name.str);
1165 		slash = strrchr(incdir, '/');
1166 		if (slash != NULL) {
1167 			*slash = '\0';
1168 			/*
1169 			 * Now do lexical processing of leading "../" on the
1170 			 * filename.
1171 			 */
1172 			for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
1173 				slash = strrchr(incdir + 1, '/');
1174 				if (slash == NULL || strcmp(slash, "/..") == 0)
1175 					break;
1176 				*slash = '\0';
1177 			}
1178 			newName = str_concat3(incdir, "/", file + i);
1179 			fullname = Dir_FindFile(newName, parseIncPath);
1180 			if (fullname == NULL)
1181 				fullname = Dir_FindFile(newName,
1182 				    &dirSearchPath);
1183 			free(newName);
1184 		}
1185 		free(incdir);
1186 
1187 		if (fullname == NULL) {
1188 			/*
1189 			 * Makefile wasn't found in same directory as included
1190 			 * makefile.
1191 			 *
1192 			 * Search for it first on the -I search path, then on
1193 			 * the .PATH search path, if not found in a -I
1194 			 * directory. If we have a suffix-specific path, we
1195 			 * should use that.
1196 			 */
1197 			const char *suff;
1198 			SearchPath *suffPath = NULL;
1199 
1200 			if ((suff = strrchr(file, '.')) != NULL) {
1201 				suffPath = Suff_GetPath(suff);
1202 				if (suffPath != NULL)
1203 					fullname = Dir_FindFile(file, suffPath);
1204 			}
1205 			if (fullname == NULL) {
1206 				fullname = Dir_FindFile(file, parseIncPath);
1207 				if (fullname == NULL)
1208 					fullname = Dir_FindFile(file,
1209 					    &dirSearchPath);
1210 			}
1211 		}
1212 	}
1213 
1214 	/* Looking for a system file or file still not found */
1215 	if (fullname == NULL) {
1216 		/*
1217 		 * Look for it on the system path
1218 		 */
1219 		SearchPath *path = Lst_IsEmpty(&sysIncPath->dirs)
1220 		    ? defSysIncPath : sysIncPath;
1221 		fullname = Dir_FindFile(file, path);
1222 	}
1223 
1224 	if (fullname == NULL) {
1225 		if (!silent)
1226 			Parse_Error(PARSE_FATAL, "Could not find %s", file);
1227 		return;
1228 	}
1229 
1230 	/* Actually open the file... */
1231 	fd = open(fullname, O_RDONLY);
1232 	if (fd == -1) {
1233 		if (!silent)
1234 			Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
1235 		free(fullname);
1236 		return;
1237 	}
1238 
1239 	buf = loadfile(fullname, fd);
1240 	(void)close(fd);
1241 
1242 	Parse_PushInput(fullname, 1, 0, buf, NULL);
1243 	if (depinc)
1244 		doing_depend = depinc;	/* only turn it on */
1245 	free(fullname);
1246 }
1247 
1248 /* Handle a "dependency" line like '.SPECIAL:' without any sources. */
1249 static void
1250 HandleDependencySourcesEmpty(ParseSpecial special, SearchPathList *paths)
1251 {
1252 	switch (special) {
1253 	case SP_SUFFIXES:
1254 		Suff_ClearSuffixes();
1255 		break;
1256 	case SP_PRECIOUS:
1257 		allPrecious = true;
1258 		break;
1259 	case SP_IGNORE:
1260 		opts.ignoreErrors = true;
1261 		break;
1262 	case SP_SILENT:
1263 		opts.silent = true;
1264 		break;
1265 	case SP_PATH:
1266 		ClearPaths(paths);
1267 		break;
1268 #ifdef POSIX
1269 	case SP_POSIX:
1270 		Global_Set("%POSIX", "1003.2");
1271 		{
1272 			static bool first_posix = true;
1273 
1274 			/*
1275 			 * Since .POSIX: should be the first
1276 			 * operative line in a makefile,
1277 			 * if '-r' flag is used, no default rules have
1278 			 * been read yet, in which case 'posix.mk' can
1279 			 * be a substiute for 'sys.mk'.
1280 			 * If '-r' is not used, then 'posix.mk' acts
1281 			 * as an extension of 'sys.mk'.
1282 			 */
1283 			if (first_posix) {
1284 				first_posix = false;
1285 				IncludeFile("posix.mk", true, false, true);
1286 			}
1287 		}
1288 		break;
1289 #endif
1290 	default:
1291 		break;
1292 	}
1293 }
1294 
1295 static void
1296 AddToPaths(const char *dir, SearchPathList *paths)
1297 {
1298 	if (paths != NULL) {
1299 		SearchPathListNode *ln;
1300 		for (ln = paths->first; ln != NULL; ln = ln->next)
1301 			(void)SearchPath_Add(ln->datum, dir);
1302 	}
1303 }
1304 
1305 /*
1306  * If the target was one that doesn't take files as its sources but takes
1307  * something like suffixes, we take each space-separated word on the line as
1308  * a something and deal with it accordingly.
1309  */
1310 static void
1311 ParseDependencySourceSpecial(ParseSpecial special, const char *word,
1312 			     SearchPathList *paths)
1313 {
1314 	switch (special) {
1315 	case SP_SUFFIXES:
1316 		Suff_AddSuffix(word);
1317 		break;
1318 	case SP_PATH:
1319 		AddToPaths(word, paths);
1320 		break;
1321 	case SP_INCLUDES:
1322 		Suff_AddInclude(word);
1323 		break;
1324 	case SP_LIBS:
1325 		Suff_AddLib(word);
1326 		break;
1327 	case SP_NULL:
1328 		Suff_SetNull(word);
1329 		break;
1330 	case SP_OBJDIR:
1331 		Main_SetObjdir(false, "%s", word);
1332 		break;
1333 	default:
1334 		break;
1335 	}
1336 }
1337 
1338 static bool
1339 ApplyDependencyTarget(char *name, char *nameEnd, ParseSpecial *inout_special,
1340 		      GNodeType *inout_targetAttr,
1341 		      SearchPathList **inout_paths)
1342 {
1343 	char savec = *nameEnd;
1344 	*nameEnd = '\0';
1345 
1346 	if (!HandleDependencyTarget(name, inout_special,
1347 	    inout_targetAttr, inout_paths))
1348 		return false;
1349 
1350 	if (*inout_special == SP_NOT && *name != '\0')
1351 		HandleDependencyTargetMundane(name);
1352 	else if (*inout_special == SP_PATH && *name != '.' && *name != '\0')
1353 		Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", name);
1354 
1355 	*nameEnd = savec;
1356 	return true;
1357 }
1358 
1359 static bool
1360 ParseDependencyTargets(char **inout_cp,
1361 		       const char *lstart,
1362 		       ParseSpecial *inout_special,
1363 		       GNodeType *inout_targetAttr,
1364 		       SearchPathList **inout_paths)
1365 {
1366 	char *cp = *inout_cp;
1367 
1368 	for (;;) {
1369 		char *tgt = cp;
1370 
1371 		ParseDependencyTargetWord(&cp, lstart);
1372 
1373 		/*
1374 		 * If the word is followed by a left parenthesis, it's the
1375 		 * name of one or more files inside an archive.
1376 		 */
1377 		if (!IsEscaped(lstart, cp) && *cp == '(') {
1378 			cp = tgt;
1379 			if (!Arch_ParseArchive(&cp, targets, SCOPE_CMDLINE)) {
1380 				Parse_Error(PARSE_FATAL,
1381 				    "Error in archive specification: \"%s\"",
1382 				    tgt);
1383 				return false;
1384 			}
1385 			continue;
1386 		}
1387 
1388 		if (*cp == '\0') {
1389 			InvalidLineType(lstart);
1390 			return false;
1391 		}
1392 
1393 		if (!ApplyDependencyTarget(tgt, cp, inout_special,
1394 		    inout_targetAttr, inout_paths))
1395 			return false;
1396 
1397 		if (*inout_special != SP_NOT && *inout_special != SP_PATH)
1398 			SkipExtraTargets(&cp, lstart);
1399 		else
1400 			pp_skip_whitespace(&cp);
1401 
1402 		if (*cp == '\0')
1403 			break;
1404 		if ((*cp == '!' || *cp == ':') && !IsEscaped(lstart, cp))
1405 			break;
1406 	}
1407 
1408 	*inout_cp = cp;
1409 	return true;
1410 }
1411 
1412 static void
1413 ParseDependencySourcesSpecial(char *start,
1414 			      ParseSpecial special, SearchPathList *paths)
1415 {
1416 	char savec;
1417 
1418 	while (*start != '\0') {
1419 		char *end = start;
1420 		while (*end != '\0' && !ch_isspace(*end))
1421 			end++;
1422 		savec = *end;
1423 		*end = '\0';
1424 		ParseDependencySourceSpecial(special, start, paths);
1425 		*end = savec;
1426 		if (savec != '\0')
1427 			end++;
1428 		pp_skip_whitespace(&end);
1429 		start = end;
1430 	}
1431 }
1432 
1433 static void
1434 LinkVarToTargets(VarAssign *var)
1435 {
1436 	GNodeListNode *ln;
1437 
1438 	for (ln = targets->first; ln != NULL; ln = ln->next)
1439 		Parse_Var(var, ln->datum);
1440 }
1441 
1442 static bool
1443 ParseDependencySourcesMundane(char *start,
1444 			      ParseSpecial special, GNodeType targetAttr)
1445 {
1446 	while (*start != '\0') {
1447 		char *end = start;
1448 		VarAssign var;
1449 
1450 		/*
1451 		 * Check for local variable assignment,
1452 		 * rest of the line is the value.
1453 		 */
1454 		if (Parse_IsVar(start, &var)) {
1455 			/*
1456 			 * Check if this makefile has disabled
1457 			 * setting local variables.
1458 			 */
1459 			bool target_vars = GetBooleanExpr(
1460 			    "${.MAKE.TARGET_LOCAL_VARIABLES}", true);
1461 
1462 			if (target_vars)
1463 				LinkVarToTargets(&var);
1464 			free(var.varname);
1465 			if (target_vars)
1466 				return true;
1467 		}
1468 
1469 		/*
1470 		 * The targets take real sources, so we must beware of archive
1471 		 * specifications (i.e. things with left parentheses in them)
1472 		 * and handle them accordingly.
1473 		 */
1474 		for (; *end != '\0' && !ch_isspace(*end); end++) {
1475 			if (*end == '(' && end > start && end[-1] != '$') {
1476 				/*
1477 				 * Only stop for a left parenthesis if it
1478 				 * isn't at the start of a word (that'll be
1479 				 * for variable changes later) and isn't
1480 				 * preceded by a dollar sign (a dynamic
1481 				 * source).
1482 				 */
1483 				break;
1484 			}
1485 		}
1486 
1487 		if (*end == '(') {
1488 			GNodeList sources = LST_INIT;
1489 			if (!Arch_ParseArchive(&start, &sources,
1490 			    SCOPE_CMDLINE)) {
1491 				Parse_Error(PARSE_FATAL,
1492 				    "Error in source archive spec \"%s\"",
1493 				    start);
1494 				return false;
1495 			}
1496 
1497 			while (!Lst_IsEmpty(&sources)) {
1498 				GNode *gn = Lst_Dequeue(&sources);
1499 				ApplyDependencySource(targetAttr, gn->name,
1500 				    special);
1501 			}
1502 			Lst_Done(&sources);
1503 			end = start;
1504 		} else {
1505 			if (*end != '\0') {
1506 				*end = '\0';
1507 				end++;
1508 			}
1509 
1510 			ApplyDependencySource(targetAttr, start, special);
1511 		}
1512 		pp_skip_whitespace(&end);
1513 		start = end;
1514 	}
1515 	return true;
1516 }
1517 
1518 /*
1519  * From a dependency line like 'targets: sources', parse the sources.
1520  *
1521  * See the tests depsrc-*.mk.
1522  */
1523 static void
1524 ParseDependencySources(char *p, GNodeType targetAttr,
1525 		       ParseSpecial special, SearchPathList **inout_paths)
1526 {
1527 	if (*p == '\0') {
1528 		HandleDependencySourcesEmpty(special, *inout_paths);
1529 	} else if (special == SP_MFLAGS) {
1530 		Main_ParseArgLine(p);
1531 		return;
1532 	} else if (special == SP_SHELL) {
1533 		if (!Job_ParseShell(p)) {
1534 			Parse_Error(PARSE_FATAL,
1535 			    "improper shell specification");
1536 			return;
1537 		}
1538 		return;
1539 	} else if (special == SP_NOTPARALLEL || special == SP_SINGLESHELL ||
1540 		   special == SP_DELETE_ON_ERROR) {
1541 		return;
1542 	}
1543 
1544 	/* Now go for the sources. */
1545 	if (special == SP_SUFFIXES || special == SP_PATH ||
1546 	    special == SP_INCLUDES || special == SP_LIBS ||
1547 	    special == SP_NULL || special == SP_OBJDIR) {
1548 		ParseDependencySourcesSpecial(p, special, *inout_paths);
1549 		if (*inout_paths != NULL) {
1550 			Lst_Free(*inout_paths);
1551 			*inout_paths = NULL;
1552 		}
1553 		if (special == SP_PATH)
1554 			Dir_SetPATH();
1555 	} else {
1556 		assert(*inout_paths == NULL);
1557 		if (!ParseDependencySourcesMundane(p, special, targetAttr))
1558 			return;
1559 	}
1560 
1561 	MaybeUpdateMainTarget();
1562 }
1563 
1564 /*
1565  * Parse a dependency line consisting of targets, followed by a dependency
1566  * operator, optionally followed by sources.
1567  *
1568  * The nodes of the sources are linked as children to the nodes of the
1569  * targets. Nodes are created as necessary.
1570  *
1571  * The operator is applied to each node in the global 'targets' list,
1572  * which is where the nodes found for the targets are kept.
1573  *
1574  * The sources are parsed in much the same way as the targets, except
1575  * that they are expanded using the wildcarding scheme of the C-Shell,
1576  * and a target is created for each expanded word. Each of the resulting
1577  * nodes is then linked to each of the targets as one of its children.
1578  *
1579  * Certain targets and sources such as .PHONY or .PRECIOUS are handled
1580  * specially, see ParseSpecial.
1581  *
1582  * Transformation rules such as '.c.o' are also handled here, see
1583  * Suff_AddTransform.
1584  *
1585  * Upon return, the value of the line is unspecified.
1586  */
1587 static void
1588 ParseDependency(char *line)
1589 {
1590 	char *p;
1591 	SearchPathList *paths;	/* search paths to alter when parsing a list
1592 				 * of .PATH targets */
1593 	GNodeType targetAttr;	/* from special sources */
1594 	ParseSpecial special;	/* in special targets, the children are
1595 				 * linked as children of the parent but not
1596 				 * vice versa */
1597 
1598 	DEBUG1(PARSE, "ParseDependency(%s)\n", line);
1599 	p = line;
1600 	paths = NULL;
1601 	targetAttr = OP_NONE;
1602 	special = SP_NOT;
1603 
1604 	if (!ParseDependencyTargets(&p, line, &special, &targetAttr, &paths))
1605 		goto out;
1606 
1607 	if (!Lst_IsEmpty(targets))
1608 		CheckSpecialMundaneMixture(special);
1609 
1610 	ApplyDependencyOperator(ParseDependencyOp(&p));
1611 
1612 	pp_skip_whitespace(&p);
1613 
1614 	ParseDependencySources(p, targetAttr, special, &paths);
1615 
1616 out:
1617 	if (paths != NULL)
1618 		Lst_Free(paths);
1619 }
1620 
1621 /*
1622  * Determine the assignment operator and adjust the end of the variable
1623  * name accordingly.
1624  */
1625 static VarAssign
1626 AdjustVarassignOp(const char *name, const char *nameEnd, const char *op,
1627 		  const char *value)
1628 {
1629 	VarAssignOp type;
1630 	VarAssign va;
1631 
1632 	if (op > name && op[-1] == '+') {
1633 		op--;
1634 		type = VAR_APPEND;
1635 
1636 	} else if (op > name && op[-1] == '?') {
1637 		op--;
1638 		type = VAR_DEFAULT;
1639 
1640 	} else if (op > name && op[-1] == ':') {
1641 		op--;
1642 		type = VAR_SUBST;
1643 
1644 	} else if (op > name && op[-1] == '!') {
1645 		op--;
1646 		type = VAR_SHELL;
1647 
1648 	} else {
1649 		type = VAR_NORMAL;
1650 #ifdef SUNSHCMD
1651 		while (op > name && ch_isspace(op[-1]))
1652 			op--;
1653 
1654 		if (op - name >= 3 && memcmp(op - 3, ":sh", 3) == 0) {
1655 			op -= 3;
1656 			type = VAR_SHELL;
1657 		}
1658 #endif
1659 	}
1660 
1661 	va.varname = bmake_strsedup(name, nameEnd < op ? nameEnd : op);
1662 	va.op = type;
1663 	va.value = value;
1664 	return va;
1665 }
1666 
1667 /*
1668  * Parse a variable assignment, consisting of a single-word variable name,
1669  * optional whitespace, an assignment operator, optional whitespace and the
1670  * variable value.
1671  *
1672  * Note: There is a lexical ambiguity with assignment modifier characters
1673  * in variable names. This routine interprets the character before the =
1674  * as a modifier. Therefore, an assignment like
1675  *	C++=/usr/bin/CC
1676  * is interpreted as "C+ +=" instead of "C++ =".
1677  *
1678  * Used for both lines in a file and command line arguments.
1679  */
1680 static bool
1681 Parse_IsVar(const char *p, VarAssign *out_var)
1682 {
1683 	const char *nameStart, *nameEnd, *firstSpace, *eq;
1684 	int level = 0;
1685 
1686 	cpp_skip_hspace(&p);	/* Skip to variable name */
1687 
1688 	/*
1689 	 * During parsing, the '+' of the operator '+=' is initially parsed
1690 	 * as part of the variable name.  It is later corrected, as is the
1691 	 * ':sh' modifier. Of these two (nameEnd and eq), the earlier one
1692 	 * determines the actual end of the variable name.
1693 	 */
1694 
1695 	nameStart = p;
1696 	firstSpace = NULL;
1697 
1698 	/*
1699 	 * Scan for one of the assignment operators outside a variable
1700 	 * expansion.
1701 	 */
1702 	while (*p != '\0') {
1703 		char ch = *p++;
1704 		if (ch == '(' || ch == '{') {
1705 			level++;
1706 			continue;
1707 		}
1708 		if (ch == ')' || ch == '}') {
1709 			level--;
1710 			continue;
1711 		}
1712 
1713 		if (level != 0)
1714 			continue;
1715 
1716 		if ((ch == ' ' || ch == '\t') && firstSpace == NULL)
1717 			firstSpace = p - 1;
1718 		while (ch == ' ' || ch == '\t')
1719 			ch = *p++;
1720 
1721 		if (ch == '\0')
1722 			return false;
1723 #ifdef SUNSHCMD
1724 		if (ch == ':' && p[0] == 's' && p[1] == 'h') {
1725 			p += 2;
1726 			continue;
1727 		}
1728 #endif
1729 		if (ch == '=')
1730 			eq = p - 1;
1731 		else if (*p == '=' &&
1732 		    (ch == '+' || ch == ':' || ch == '?' || ch == '!'))
1733 			eq = p;
1734 		else if (firstSpace != NULL)
1735 			return false;
1736 		else
1737 			continue;
1738 
1739 		nameEnd = firstSpace != NULL ? firstSpace : eq;
1740 		p = eq + 1;
1741 		cpp_skip_whitespace(&p);
1742 		*out_var = AdjustVarassignOp(nameStart, nameEnd, eq, p);
1743 		return true;
1744 	}
1745 
1746 	return false;
1747 }
1748 
1749 /*
1750  * Check for syntax errors such as unclosed expressions or unknown modifiers.
1751  */
1752 static void
1753 VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *scope)
1754 {
1755 	if (opts.strict) {
1756 		if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
1757 			char *expandedValue;
1758 
1759 			(void)Var_Subst(uvalue, scope, VARE_PARSE_ONLY,
1760 			    &expandedValue);
1761 			/* TODO: handle errors */
1762 			free(expandedValue);
1763 		}
1764 	}
1765 }
1766 
1767 /* Perform a variable assignment that uses the operator ':='. */
1768 static void
1769 VarAssign_EvalSubst(GNode *scope, const char *name, const char *uvalue,
1770 		    FStr *out_avalue)
1771 {
1772 	char *evalue;
1773 
1774 	/*
1775 	 * make sure that we set the variable the first time to nothing
1776 	 * so that it gets substituted.
1777 	 *
1778 	 * TODO: Add a test that demonstrates why this code is needed,
1779 	 *  apart from making the debug log longer.
1780 	 *
1781 	 * XXX: The variable name is expanded up to 3 times.
1782 	 */
1783 	if (!Var_ExistsExpand(scope, name))
1784 		Var_SetExpand(scope, name, "");
1785 
1786 	(void)Var_Subst(uvalue, scope, VARE_KEEP_DOLLAR_UNDEF, &evalue);
1787 	/* TODO: handle errors */
1788 
1789 	Var_SetExpand(scope, name, evalue);
1790 
1791 	*out_avalue = FStr_InitOwn(evalue);
1792 }
1793 
1794 /* Perform a variable assignment that uses the operator '!='. */
1795 static void
1796 VarAssign_EvalShell(const char *name, const char *uvalue, GNode *scope,
1797 		    FStr *out_avalue)
1798 {
1799 	FStr cmd;
1800 	char *output, *error;
1801 
1802 	cmd = FStr_InitRefer(uvalue);
1803 	Var_Expand(&cmd, SCOPE_CMDLINE, VARE_UNDEFERR);
1804 
1805 	output = Cmd_Exec(cmd.str, &error);
1806 	Var_SetExpand(scope, name, output);
1807 	*out_avalue = FStr_InitOwn(output);
1808 	if (error != NULL) {
1809 		Parse_Error(PARSE_WARNING, "%s", error);
1810 		free(error);
1811 	}
1812 
1813 	FStr_Done(&cmd);
1814 }
1815 
1816 /*
1817  * Perform a variable assignment.
1818  *
1819  * The actual value of the variable is returned in *out_true_avalue.
1820  * Especially for VAR_SUBST and VAR_SHELL this can differ from the literal
1821  * value.
1822  *
1823  * Return whether the assignment was actually performed, which is usually
1824  * the case.  It is only skipped if the operator is '?=' and the variable
1825  * already exists.
1826  */
1827 static bool
1828 VarAssign_Eval(const char *name, VarAssignOp op, const char *uvalue,
1829 	       GNode *scope, FStr *out_true_avalue)
1830 {
1831 	FStr avalue = FStr_InitRefer(uvalue);
1832 
1833 	if (op == VAR_APPEND)
1834 		Var_AppendExpand(scope, name, uvalue);
1835 	else if (op == VAR_SUBST)
1836 		VarAssign_EvalSubst(scope, name, uvalue, &avalue);
1837 	else if (op == VAR_SHELL)
1838 		VarAssign_EvalShell(name, uvalue, scope, &avalue);
1839 	else {
1840 		/* XXX: The variable name is expanded up to 2 times. */
1841 		if (op == VAR_DEFAULT && Var_ExistsExpand(scope, name))
1842 			return false;
1843 
1844 		/* Normal assignment -- just do it. */
1845 		Var_SetExpand(scope, name, uvalue);
1846 	}
1847 
1848 	*out_true_avalue = avalue;
1849 	return true;
1850 }
1851 
1852 static void
1853 VarAssignSpecial(const char *name, const char *avalue)
1854 {
1855 	if (strcmp(name, MAKEOVERRIDES) == 0)
1856 		Main_ExportMAKEFLAGS(false);	/* re-export MAKEFLAGS */
1857 	else if (strcmp(name, ".CURDIR") == 0) {
1858 		/*
1859 		 * Someone is being (too?) clever...
1860 		 * Let's pretend they know what they are doing and
1861 		 * re-initialize the 'cur' CachedDir.
1862 		 */
1863 		Dir_InitCur(avalue);
1864 		Dir_SetPATH();
1865 	} else if (strcmp(name, MAKE_JOB_PREFIX) == 0)
1866 		Job_SetPrefix();
1867 	else if (strcmp(name, MAKE_EXPORTED) == 0)
1868 		Var_ExportVars(avalue);
1869 }
1870 
1871 /* Perform the variable assignment in the given scope. */
1872 static void
1873 Parse_Var(VarAssign *var, GNode *scope)
1874 {
1875 	FStr avalue;		/* actual value (maybe expanded) */
1876 
1877 	VarCheckSyntax(var->op, var->value, scope);
1878 	if (VarAssign_Eval(var->varname, var->op, var->value, scope, &avalue)) {
1879 		VarAssignSpecial(var->varname, avalue.str);
1880 		FStr_Done(&avalue);
1881 	}
1882 }
1883 
1884 
1885 /*
1886  * See if the command possibly calls a sub-make by using the variable
1887  * expressions ${.MAKE}, ${MAKE} or the plain word "make".
1888  */
1889 static bool
1890 MaybeSubMake(const char *cmd)
1891 {
1892 	const char *start;
1893 
1894 	for (start = cmd; *start != '\0'; start++) {
1895 		const char *p = start;
1896 		char endc;
1897 
1898 		/* XXX: What if progname != "make"? */
1899 		if (strncmp(p, "make", 4) == 0)
1900 			if (start == cmd || !ch_isalnum(p[-1]))
1901 				if (!ch_isalnum(p[4]))
1902 					return true;
1903 
1904 		if (*p != '$')
1905 			continue;
1906 		p++;
1907 
1908 		if (*p == '{')
1909 			endc = '}';
1910 		else if (*p == '(')
1911 			endc = ')';
1912 		else
1913 			continue;
1914 		p++;
1915 
1916 		if (*p == '.')	/* Accept either ${.MAKE} or ${MAKE}. */
1917 			p++;
1918 
1919 		if (strncmp(p, "MAKE", 4) == 0 && p[4] == endc)
1920 			return true;
1921 	}
1922 	return false;
1923 }
1924 
1925 /*
1926  * Append the command to the target node.
1927  *
1928  * The node may be marked as a submake node if the command is determined to
1929  * be that.
1930  */
1931 static void
1932 GNode_AddCommand(GNode *gn, char *cmd)
1933 {
1934 	/* Add to last (ie current) cohort for :: targets */
1935 	if ((gn->type & OP_DOUBLEDEP) && gn->cohorts.last != NULL)
1936 		gn = gn->cohorts.last->datum;
1937 
1938 	/* if target already supplied, ignore commands */
1939 	if (!(gn->type & OP_HAS_COMMANDS)) {
1940 		Lst_Append(&gn->commands, cmd);
1941 		if (MaybeSubMake(cmd))
1942 			gn->type |= OP_SUBMAKE;
1943 		RememberLocation(gn);
1944 	} else {
1945 #if 0
1946 		/* XXX: We cannot do this until we fix the tree */
1947 		Lst_Append(&gn->commands, cmd);
1948 		Parse_Error(PARSE_WARNING,
1949 		    "overriding commands for target \"%s\"; "
1950 		    "previous commands defined at %s: %u ignored",
1951 		    gn->name, gn->fname, gn->lineno);
1952 #else
1953 		Parse_Error(PARSE_WARNING,
1954 		    "duplicate script for target \"%s\" ignored",
1955 		    gn->name);
1956 		ParseErrorInternal(gn->fname, gn->lineno, PARSE_WARNING,
1957 		    "using previous script for \"%s\" defined here",
1958 		    gn->name);
1959 #endif
1960 	}
1961 }
1962 
1963 /*
1964  * Add a directory to the path searched for included makefiles bracketed
1965  * by double-quotes.
1966  */
1967 void
1968 Parse_AddIncludeDir(const char *dir)
1969 {
1970 	(void)SearchPath_Add(parseIncPath, dir);
1971 }
1972 
1973 
1974 /*
1975  * Parse a directive like '.include' or '.-include'.
1976  *
1977  * .include "user-makefile.mk"
1978  * .include <system-makefile.mk>
1979  */
1980 static void
1981 ParseInclude(char *directive)
1982 {
1983 	char endc;		/* '>' or '"' */
1984 	char *p;
1985 	bool silent = directive[0] != 'i';
1986 	FStr file;
1987 
1988 	p = directive + (silent ? 8 : 7);
1989 	pp_skip_hspace(&p);
1990 
1991 	if (*p != '"' && *p != '<') {
1992 		Parse_Error(PARSE_FATAL,
1993 		    ".include filename must be delimited by '\"' or '<'");
1994 		return;
1995 	}
1996 
1997 	if (*p++ == '<')
1998 		endc = '>';
1999 	else
2000 		endc = '"';
2001 	file = FStr_InitRefer(p);
2002 
2003 	/* Skip to matching delimiter */
2004 	while (*p != '\0' && *p != endc)
2005 		p++;
2006 
2007 	if (*p != endc) {
2008 		Parse_Error(PARSE_FATAL,
2009 		    "Unclosed .include filename. '%c' expected", endc);
2010 		return;
2011 	}
2012 
2013 	*p = '\0';
2014 
2015 	Var_Expand(&file, SCOPE_CMDLINE, VARE_WANTRES);
2016 	IncludeFile(file.str, endc == '>', directive[0] == 'd', silent);
2017 	FStr_Done(&file);
2018 }
2019 
2020 /*
2021  * Split filename into dirname + basename, then assign these to the
2022  * given variables.
2023  */
2024 static void
2025 SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
2026 {
2027 	const char *slash, *basename;
2028 	FStr dirname;
2029 
2030 	slash = strrchr(filename, '/');
2031 	if (slash == NULL) {
2032 		dirname = FStr_InitRefer(curdir);
2033 		basename = filename;
2034 	} else {
2035 		dirname = FStr_InitOwn(bmake_strsedup(filename, slash));
2036 		basename = slash + 1;
2037 	}
2038 
2039 	Global_Set(dirvar, dirname.str);
2040 	Global_Set(filevar, basename);
2041 
2042 	DEBUG4(PARSE, "SetFilenameVars: ${%s} = `%s' ${%s} = `%s'\n",
2043 	    dirvar, dirname.str, filevar, basename);
2044 	FStr_Done(&dirname);
2045 }
2046 
2047 /*
2048  * Return the immediately including file.
2049  *
2050  * This is made complicated since the .for loop is implemented as a special
2051  * kind of .include; see For_Run.
2052  */
2053 static const char *
2054 GetActuallyIncludingFile(void)
2055 {
2056 	size_t i;
2057 	const IncludedFile *incs = GetInclude(0);
2058 
2059 	for (i = includes.len; i >= 2; i--)
2060 		if (incs[i - 1].forLoop == NULL)
2061 			return incs[i - 2].name.str;
2062 	return NULL;
2063 }
2064 
2065 /* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
2066 static void
2067 SetParseFile(const char *filename)
2068 {
2069 	const char *including;
2070 
2071 	SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");
2072 
2073 	including = GetActuallyIncludingFile();
2074 	if (including != NULL) {
2075 		SetFilenameVars(including,
2076 		    ".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
2077 	} else {
2078 		Global_Delete(".INCLUDEDFROMDIR");
2079 		Global_Delete(".INCLUDEDFROMFILE");
2080 	}
2081 }
2082 
2083 static bool
2084 StrContainsWord(const char *str, const char *word)
2085 {
2086 	size_t strLen = strlen(str);
2087 	size_t wordLen = strlen(word);
2088 	const char *p;
2089 
2090 	if (strLen < wordLen)
2091 		return false;
2092 
2093 	for (p = str; p != NULL; p = strchr(p, ' ')) {
2094 		if (*p == ' ')
2095 			p++;
2096 		if (p > str + strLen - wordLen)
2097 			return false;
2098 
2099 		if (memcmp(p, word, wordLen) == 0 &&
2100 		    (p[wordLen] == '\0' || p[wordLen] == ' '))
2101 			return true;
2102 	}
2103 	return false;
2104 }
2105 
2106 /*
2107  * XXX: Searching through a set of words with this linear search is
2108  * inefficient for variables that contain thousands of words.
2109  *
2110  * XXX: The paths in this list don't seem to be normalized in any way.
2111  */
2112 static bool
2113 VarContainsWord(const char *varname, const char *word)
2114 {
2115 	FStr val = Var_Value(SCOPE_GLOBAL, varname);
2116 	bool found = val.str != NULL && StrContainsWord(val.str, word);
2117 	FStr_Done(&val);
2118 	return found;
2119 }
2120 
2121 /*
2122  * Track the makefiles we read - so makefiles can set dependencies on them.
2123  * Avoid adding anything more than once.
2124  *
2125  * Time complexity: O(n) per call, in total O(n^2), where n is the number
2126  * of makefiles that have been loaded.
2127  */
2128 static void
2129 TrackInput(const char *name)
2130 {
2131 	if (!VarContainsWord(MAKE_MAKEFILES, name))
2132 		Global_Append(MAKE_MAKEFILES, name);
2133 }
2134 
2135 
2136 /* Parse from the given buffer, later return to the current file. */
2137 void
2138 Parse_PushInput(const char *name, unsigned lineno, unsigned readLines,
2139 		Buffer buf, struct ForLoop *forLoop)
2140 {
2141 	IncludedFile *curFile;
2142 
2143 	if (forLoop != NULL)
2144 		name = CurFile()->name.str;
2145 	else
2146 		TrackInput(name);
2147 
2148 	DEBUG3(PARSE, "Parse_PushInput: %s %s, line %u\n",
2149 	    forLoop != NULL ? ".for loop in": "file", name, lineno);
2150 
2151 	curFile = Vector_Push(&includes);
2152 	curFile->name = FStr_InitOwn(bmake_strdup(name));
2153 	curFile->lineno = lineno;
2154 	curFile->readLines = readLines;
2155 	curFile->forHeadLineno = lineno;
2156 	curFile->forBodyReadLines = readLines;
2157 	curFile->buf = buf;
2158 	curFile->depending = doing_depend;	/* restore this on EOF */
2159 	curFile->forLoop = forLoop;
2160 
2161 	if (forLoop != NULL && !For_NextIteration(forLoop, &curFile->buf))
2162 		abort();	/* see For_Run */
2163 
2164 	curFile->buf_ptr = curFile->buf.data;
2165 	curFile->buf_end = curFile->buf.data + curFile->buf.len;
2166 	curFile->cond_depth = Cond_save_depth();
2167 	SetParseFile(name);
2168 }
2169 
2170 /* Check if the directive is an include directive. */
2171 static bool
2172 IsInclude(const char *dir, bool sysv)
2173 {
2174 	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
2175 		dir++;
2176 
2177 	if (strncmp(dir, "include", 7) != 0)
2178 		return false;
2179 
2180 	/* Space is not mandatory for BSD .include */
2181 	return !sysv || ch_isspace(dir[7]);
2182 }
2183 
2184 
2185 #ifdef SYSVINCLUDE
2186 /* Check if the line is a SYSV include directive. */
2187 static bool
2188 IsSysVInclude(const char *line)
2189 {
2190 	const char *p;
2191 
2192 	if (!IsInclude(line, true))
2193 		return false;
2194 
2195 	/* Avoid interpreting a dependency line as an include */
2196 	for (p = line; (p = strchr(p, ':')) != NULL;) {
2197 
2198 		/* end of line -> it's a dependency */
2199 		if (*++p == '\0')
2200 			return false;
2201 
2202 		/* '::' operator or ': ' -> it's a dependency */
2203 		if (*p == ':' || ch_isspace(*p))
2204 			return false;
2205 	}
2206 	return true;
2207 }
2208 
2209 /* Push to another file.  The line points to the word "include". */
2210 static void
2211 ParseTraditionalInclude(char *line)
2212 {
2213 	char *cp;		/* current position in file spec */
2214 	bool done = false;
2215 	bool silent = line[0] != 'i';
2216 	char *file = line + (silent ? 8 : 7);
2217 	char *all_files;
2218 
2219 	DEBUG1(PARSE, "ParseTraditionalInclude: %s\n", file);
2220 
2221 	pp_skip_whitespace(&file);
2222 
2223 	(void)Var_Subst(file, SCOPE_CMDLINE, VARE_WANTRES, &all_files);
2224 	/* TODO: handle errors */
2225 
2226 	for (file = all_files; !done; file = cp + 1) {
2227 		/* Skip to end of line or next whitespace */
2228 		for (cp = file; *cp != '\0' && !ch_isspace(*cp); cp++)
2229 			continue;
2230 
2231 		if (*cp != '\0')
2232 			*cp = '\0';
2233 		else
2234 			done = true;
2235 
2236 		IncludeFile(file, false, false, silent);
2237 	}
2238 
2239 	free(all_files);
2240 }
2241 #endif
2242 
2243 #ifdef GMAKEEXPORT
2244 /* Parse "export <variable>=<value>", and actually export it. */
2245 static void
2246 ParseGmakeExport(char *line)
2247 {
2248 	char *variable = line + 6;
2249 	char *value;
2250 
2251 	DEBUG1(PARSE, "ParseGmakeExport: %s\n", variable);
2252 
2253 	pp_skip_whitespace(&variable);
2254 
2255 	for (value = variable; *value != '\0' && *value != '='; value++)
2256 		continue;
2257 
2258 	if (*value != '=') {
2259 		Parse_Error(PARSE_FATAL,
2260 		    "Variable/Value missing from \"export\"");
2261 		return;
2262 	}
2263 	*value++ = '\0';	/* terminate variable */
2264 
2265 	/*
2266 	 * Expand the value before putting it in the environment.
2267 	 */
2268 	(void)Var_Subst(value, SCOPE_CMDLINE, VARE_WANTRES, &value);
2269 	/* TODO: handle errors */
2270 
2271 	setenv(variable, value, 1);
2272 	free(value);
2273 }
2274 #endif
2275 
2276 /*
2277  * Called when EOF is reached in the current file. If we were reading an
2278  * include file or a .for loop, the includes stack is popped and things set
2279  * up to go back to reading the previous file at the previous location.
2280  *
2281  * Results:
2282  *	true to continue parsing, i.e. it had only reached the end of an
2283  *	included file, false if the main file has been parsed completely.
2284  */
2285 static bool
2286 ParseEOF(void)
2287 {
2288 	IncludedFile *curFile = CurFile();
2289 
2290 	doing_depend = curFile->depending;
2291 	if (curFile->forLoop != NULL &&
2292 	    For_NextIteration(curFile->forLoop, &curFile->buf)) {
2293 		curFile->buf_ptr = curFile->buf.data;
2294 		curFile->buf_end = curFile->buf.data + curFile->buf.len;
2295 		curFile->readLines = curFile->forBodyReadLines;
2296 		return true;
2297 	}
2298 
2299 	/*
2300 	 * Ensure the makefile (or .for loop) didn't have mismatched
2301 	 * conditionals.
2302 	 */
2303 	Cond_restore_depth(curFile->cond_depth);
2304 
2305 	FStr_Done(&curFile->name);
2306 	Buf_Done(&curFile->buf);
2307 	if (curFile->forLoop != NULL)
2308 		ForLoop_Free(curFile->forLoop);
2309 	Vector_Pop(&includes);
2310 
2311 	if (includes.len == 0) {
2312 		/* We've run out of input */
2313 		Global_Delete(".PARSEDIR");
2314 		Global_Delete(".PARSEFILE");
2315 		Global_Delete(".INCLUDEDFROMDIR");
2316 		Global_Delete(".INCLUDEDFROMFILE");
2317 		return false;
2318 	}
2319 
2320 	curFile = CurFile();
2321 	DEBUG2(PARSE, "ParseEOF: returning to file %s, line %u\n",
2322 	    curFile->name.str, curFile->readLines + 1);
2323 
2324 	SetParseFile(curFile->name.str);
2325 	return true;
2326 }
2327 
2328 typedef enum ParseRawLineResult {
2329 	PRLR_LINE,
2330 	PRLR_EOF,
2331 	PRLR_ERROR
2332 } ParseRawLineResult;
2333 
2334 /*
2335  * Parse until the end of a line, taking into account lines that end with
2336  * backslash-newline.  The resulting line goes from out_line to out_line_end;
2337  * the line is not null-terminated.
2338  */
2339 static ParseRawLineResult
2340 ParseRawLine(IncludedFile *curFile, char **out_line, char **out_line_end,
2341 	     char **out_firstBackslash, char **out_commentLineEnd)
2342 {
2343 	char *line = curFile->buf_ptr;
2344 	char *buf_end = curFile->buf_end;
2345 	char *p = line;
2346 	char *line_end = line;
2347 	char *firstBackslash = NULL;
2348 	char *commentLineEnd = NULL;
2349 	ParseRawLineResult res = PRLR_LINE;
2350 
2351 	curFile->readLines++;
2352 
2353 	for (;;) {
2354 		char ch;
2355 
2356 		if (p == buf_end) {
2357 			res = PRLR_EOF;
2358 			break;
2359 		}
2360 
2361 		ch = *p;
2362 		if (ch == '\0' || (ch == '\\' && p[1] == '\0')) {
2363 			Parse_Error(PARSE_FATAL, "Zero byte read from file");
2364 			return PRLR_ERROR;
2365 		}
2366 
2367 		/* Treat next character after '\' as literal. */
2368 		if (ch == '\\') {
2369 			if (firstBackslash == NULL)
2370 				firstBackslash = p;
2371 			if (p[1] == '\n') {
2372 				curFile->readLines++;
2373 				if (p + 2 == buf_end) {
2374 					line_end = p;
2375 					*line_end = '\n';
2376 					p += 2;
2377 					continue;
2378 				}
2379 			}
2380 			p += 2;
2381 			line_end = p;
2382 			assert(p <= buf_end);
2383 			continue;
2384 		}
2385 
2386 		/*
2387 		 * Remember the first '#' for comment stripping, unless
2388 		 * the previous char was '[', as in the modifier ':[#]'.
2389 		 */
2390 		if (ch == '#' && commentLineEnd == NULL &&
2391 		    !(p > line && p[-1] == '['))
2392 			commentLineEnd = line_end;
2393 
2394 		p++;
2395 		if (ch == '\n')
2396 			break;
2397 
2398 		/* We are not interested in trailing whitespace. */
2399 		if (!ch_isspace(ch))
2400 			line_end = p;
2401 	}
2402 
2403 	curFile->buf_ptr = p;
2404 	*out_line = line;
2405 	*out_line_end = line_end;
2406 	*out_firstBackslash = firstBackslash;
2407 	*out_commentLineEnd = commentLineEnd;
2408 	return res;
2409 }
2410 
2411 /*
2412  * Beginning at start, unescape '\#' to '#' and replace backslash-newline
2413  * with a single space.
2414  */
2415 static void
2416 UnescapeBackslash(char *line, char *start)
2417 {
2418 	const char *src = start;
2419 	char *dst = start;
2420 	char *spaceStart = line;
2421 
2422 	for (;;) {
2423 		char ch = *src++;
2424 		if (ch != '\\') {
2425 			if (ch == '\0')
2426 				break;
2427 			*dst++ = ch;
2428 			continue;
2429 		}
2430 
2431 		ch = *src++;
2432 		if (ch == '\0') {
2433 			/* Delete '\\' at the end of the buffer. */
2434 			dst--;
2435 			break;
2436 		}
2437 
2438 		/* Delete '\\' from before '#' on non-command lines. */
2439 		if (ch == '#' && line[0] != '\t')
2440 			*dst++ = ch;
2441 		else if (ch == '\n') {
2442 			cpp_skip_hspace(&src);
2443 			*dst++ = ' ';
2444 		} else {
2445 			/* Leave '\\' in the buffer for later. */
2446 			*dst++ = '\\';
2447 			*dst++ = ch;
2448 			/* Keep an escaped ' ' at the line end. */
2449 			spaceStart = dst;
2450 		}
2451 	}
2452 
2453 	/* Delete any trailing spaces - eg from empty continuations */
2454 	while (dst > spaceStart && ch_isspace(dst[-1]))
2455 		dst--;
2456 	*dst = '\0';
2457 }
2458 
2459 typedef enum LineKind {
2460 	/*
2461 	 * Return the next line that is neither empty nor a comment.
2462 	 * Backslash line continuations are folded into a single space.
2463 	 * A trailing comment, if any, is discarded.
2464 	 */
2465 	LK_NONEMPTY,
2466 
2467 	/*
2468 	 * Return the next line, even if it is empty or a comment.
2469 	 * Preserve backslash-newline to keep the line numbers correct.
2470 	 *
2471 	 * Used in .for loops to collect the body of the loop while waiting
2472 	 * for the corresponding .endfor.
2473 	 */
2474 	LK_FOR_BODY,
2475 
2476 	/*
2477 	 * Return the next line that starts with a dot.
2478 	 * Backslash line continuations are folded into a single space.
2479 	 * A trailing comment, if any, is discarded.
2480 	 *
2481 	 * Used in .if directives to skip over irrelevant branches while
2482 	 * waiting for the corresponding .endif.
2483 	 */
2484 	LK_DOT
2485 } LineKind;
2486 
2487 /*
2488  * Return the next "interesting" logical line from the current file.  The
2489  * returned string will be freed at the end of including the file.
2490  */
2491 static char *
2492 ReadLowLevelLine(LineKind kind)
2493 {
2494 	IncludedFile *curFile = CurFile();
2495 	ParseRawLineResult res;
2496 	char *line;
2497 	char *line_end;
2498 	char *firstBackslash;
2499 	char *commentLineEnd;
2500 
2501 	for (;;) {
2502 		curFile->lineno = curFile->readLines + 1;
2503 		res = ParseRawLine(curFile,
2504 		    &line, &line_end, &firstBackslash, &commentLineEnd);
2505 		if (res == PRLR_ERROR)
2506 			return NULL;
2507 
2508 		if (line == line_end || line == commentLineEnd) {
2509 			if (res == PRLR_EOF)
2510 				return NULL;
2511 			if (kind != LK_FOR_BODY)
2512 				continue;
2513 		}
2514 
2515 		/* We now have a line of data */
2516 		assert(ch_isspace(*line_end));
2517 		*line_end = '\0';
2518 
2519 		if (kind == LK_FOR_BODY)
2520 			return line;	/* Don't join the physical lines. */
2521 
2522 		if (kind == LK_DOT && line[0] != '.')
2523 			continue;
2524 		break;
2525 	}
2526 
2527 	if (commentLineEnd != NULL && line[0] != '\t')
2528 		*commentLineEnd = '\0';
2529 	if (firstBackslash != NULL)
2530 		UnescapeBackslash(line, firstBackslash);
2531 	return line;
2532 }
2533 
2534 static bool
2535 SkipIrrelevantBranches(void)
2536 {
2537 	const char *line;
2538 
2539 	while ((line = ReadLowLevelLine(LK_DOT)) != NULL) {
2540 		if (Cond_EvalLine(line) == CR_TRUE)
2541 			return true;
2542 		/*
2543 		 * TODO: Check for typos in .elif directives such as .elsif
2544 		 * or .elseif.
2545 		 *
2546 		 * This check will probably duplicate some of the code in
2547 		 * ParseLine.  Most of the code there cannot apply, only
2548 		 * ParseVarassign and ParseDependencyLine can, and to prevent
2549 		 * code duplication, these would need to be called with a
2550 		 * flag called onlyCheckSyntax.
2551 		 *
2552 		 * See directive-elif.mk for details.
2553 		 */
2554 	}
2555 
2556 	return false;
2557 }
2558 
2559 static bool
2560 ParseForLoop(const char *line)
2561 {
2562 	int rval;
2563 	unsigned forHeadLineno;
2564 	unsigned bodyReadLines;
2565 	int forLevel;
2566 
2567 	rval = For_Eval(line);
2568 	if (rval == 0)
2569 		return false;	/* Not a .for line */
2570 	if (rval < 0)
2571 		return true;	/* Syntax error - error printed, ignore line */
2572 
2573 	forHeadLineno = CurFile()->lineno;
2574 	bodyReadLines = CurFile()->readLines;
2575 
2576 	/* Accumulate the loop body until the matching '.endfor'. */
2577 	forLevel = 1;
2578 	do {
2579 		line = ReadLowLevelLine(LK_FOR_BODY);
2580 		if (line == NULL) {
2581 			Parse_Error(PARSE_FATAL,
2582 			    "Unexpected end of file in .for loop");
2583 			break;
2584 		}
2585 	} while (For_Accum(line, &forLevel));
2586 
2587 	For_Run(forHeadLineno, bodyReadLines);
2588 	return true;
2589 }
2590 
2591 /*
2592  * Read an entire line from the input file.
2593  *
2594  * Empty lines, .if and .for are completely handled by this function,
2595  * leaving only variable assignments, other directives, dependency lines
2596  * and shell commands to the caller.
2597  *
2598  * Return a line without trailing whitespace, or NULL for EOF.  The returned
2599  * string will be freed at the end of including the file.
2600  */
2601 static char *
2602 ReadHighLevelLine(void)
2603 {
2604 	char *line;
2605 
2606 	for (;;) {
2607 		line = ReadLowLevelLine(LK_NONEMPTY);
2608 		if (line == NULL)
2609 			return NULL;
2610 
2611 		if (line[0] != '.')
2612 			return line;
2613 
2614 		switch (Cond_EvalLine(line)) {
2615 		case CR_FALSE:	/* May also mean a syntax error. */
2616 			if (!SkipIrrelevantBranches())
2617 				return NULL;
2618 			continue;
2619 		case CR_TRUE:
2620 			continue;
2621 		case CR_ERROR:	/* Not a conditional line */
2622 			if (ParseForLoop(line))
2623 				continue;
2624 			break;
2625 		}
2626 		return line;
2627 	}
2628 }
2629 
2630 static void
2631 FinishDependencyGroup(void)
2632 {
2633 	GNodeListNode *ln;
2634 
2635 	if (targets == NULL)
2636 		return;
2637 
2638 	for (ln = targets->first; ln != NULL; ln = ln->next) {
2639 		GNode *gn = ln->datum;
2640 
2641 		Suff_EndTransform(gn);
2642 
2643 		/*
2644 		 * Mark the target as already having commands if it does, to
2645 		 * keep from having shell commands on multiple dependency
2646 		 * lines.
2647 		 */
2648 		if (!Lst_IsEmpty(&gn->commands))
2649 			gn->type |= OP_HAS_COMMANDS;
2650 	}
2651 
2652 	Lst_Free(targets);
2653 	targets = NULL;
2654 }
2655 
2656 /* Add the command to each target from the current dependency spec. */
2657 static void
2658 ParseLine_ShellCommand(const char *p)
2659 {
2660 	cpp_skip_whitespace(&p);
2661 	if (*p == '\0')
2662 		return;		/* skip empty commands */
2663 
2664 	if (targets == NULL) {
2665 		Parse_Error(PARSE_FATAL,
2666 		    "Unassociated shell command \"%s\"", p);
2667 		return;
2668 	}
2669 
2670 	{
2671 		char *cmd = bmake_strdup(p);
2672 		GNodeListNode *ln;
2673 
2674 		for (ln = targets->first; ln != NULL; ln = ln->next) {
2675 			GNode *gn = ln->datum;
2676 			GNode_AddCommand(gn, cmd);
2677 		}
2678 #ifdef CLEANUP
2679 		Lst_Append(&targCmds, cmd);
2680 #endif
2681 	}
2682 }
2683 
2684 /*
2685  * See if the line starts with one of the known directives, and if so, handle
2686  * the directive.
2687  */
2688 static bool
2689 ParseDirective(char *line)
2690 {
2691 	char *cp = line + 1;
2692 	const char *arg;
2693 	Substring dir;
2694 
2695 	pp_skip_whitespace(&cp);
2696 	if (IsInclude(cp, false)) {
2697 		ParseInclude(cp);
2698 		return true;
2699 	}
2700 
2701 	dir.start = cp;
2702 	while (ch_islower(*cp) || *cp == '-')
2703 		cp++;
2704 	dir.end = cp;
2705 
2706 	if (*cp != '\0' && !ch_isspace(*cp))
2707 		return false;
2708 
2709 	pp_skip_whitespace(&cp);
2710 	arg = cp;
2711 
2712 	if (Substring_Equals(dir, "undef"))
2713 		Var_Undef(arg);
2714 	else if (Substring_Equals(dir, "export"))
2715 		Var_Export(VEM_PLAIN, arg);
2716 	else if (Substring_Equals(dir, "export-env"))
2717 		Var_Export(VEM_ENV, arg);
2718 	else if (Substring_Equals(dir, "export-literal"))
2719 		Var_Export(VEM_LITERAL, arg);
2720 	else if (Substring_Equals(dir, "unexport"))
2721 		Var_UnExport(false, arg);
2722 	else if (Substring_Equals(dir, "unexport-env"))
2723 		Var_UnExport(true, arg);
2724 	else if (Substring_Equals(dir, "info"))
2725 		HandleMessage(PARSE_INFO, "info", arg);
2726 	else if (Substring_Equals(dir, "warning"))
2727 		HandleMessage(PARSE_WARNING, "warning", arg);
2728 	else if (Substring_Equals(dir, "error"))
2729 		HandleMessage(PARSE_FATAL, "error", arg);
2730 	else
2731 		return false;
2732 	return true;
2733 }
2734 
2735 bool
2736 Parse_VarAssign(const char *line, bool finishDependencyGroup, GNode *scope)
2737 {
2738 	VarAssign var;
2739 
2740 	if (!Parse_IsVar(line, &var))
2741 		return false;
2742 	if (finishDependencyGroup)
2743 		FinishDependencyGroup();
2744 	Parse_Var(&var, scope);
2745 	free(var.varname);
2746 	return true;
2747 }
2748 
2749 static char *
2750 FindSemicolon(char *p)
2751 {
2752 	int level = 0;
2753 
2754 	for (; *p != '\0'; p++) {
2755 		if (*p == '\\' && p[1] != '\0') {
2756 			p++;
2757 			continue;
2758 		}
2759 
2760 		if (*p == '$' && (p[1] == '(' || p[1] == '{'))
2761 			level++;
2762 		else if (level > 0 && (*p == ')' || *p == '}'))
2763 			level--;
2764 		else if (level == 0 && *p == ';')
2765 			break;
2766 	}
2767 	return p;
2768 }
2769 
2770 /*
2771  * dependency	-> [target...] op [source...] [';' command]
2772  * op		-> ':' | '::' | '!'
2773  */
2774 static void
2775 ParseDependencyLine(char *line)
2776 {
2777 	VarEvalMode emode;
2778 	char *expanded_line;
2779 	const char *shellcmd = NULL;
2780 
2781 	/*
2782 	 * For some reason - probably to make the parser impossible -
2783 	 * a ';' can be used to separate commands from dependencies.
2784 	 * Attempt to skip over ';' inside substitution patterns.
2785 	 */
2786 	{
2787 		char *semicolon = FindSemicolon(line);
2788 		if (*semicolon != '\0') {
2789 			/* Terminate the dependency list at the ';' */
2790 			*semicolon = '\0';
2791 			shellcmd = semicolon + 1;
2792 		}
2793 	}
2794 
2795 	/*
2796 	 * We now know it's a dependency line so it needs to have all
2797 	 * variables expanded before being parsed.
2798 	 *
2799 	 * XXX: Ideally the dependency line would first be split into
2800 	 * its left-hand side, dependency operator and right-hand side,
2801 	 * and then each side would be expanded on its own.  This would
2802 	 * allow for the left-hand side to allow only defined variables
2803 	 * and to allow variables on the right-hand side to be undefined
2804 	 * as well.
2805 	 *
2806 	 * Parsing the line first would also prevent that targets
2807 	 * generated from variable expressions are interpreted as the
2808 	 * dependency operator, such as in "target${:U\:} middle: source",
2809 	 * in which the middle is interpreted as a source, not a target.
2810 	 */
2811 
2812 	/*
2813 	 * In lint mode, allow undefined variables to appear in dependency
2814 	 * lines.
2815 	 *
2816 	 * Ideally, only the right-hand side would allow undefined variables
2817 	 * since it is common to have optional dependencies. Having undefined
2818 	 * variables on the left-hand side is more unusual though.  Since
2819 	 * both sides are expanded in a single pass, there is not much choice
2820 	 * what to do here.
2821 	 *
2822 	 * In normal mode, it does not matter whether undefined variables are
2823 	 * allowed or not since as of 2020-09-14, Var_Parse does not print
2824 	 * any parse errors in such a case. It simply returns the special
2825 	 * empty string var_Error, which cannot be detected in the result of
2826 	 * Var_Subst.
2827 	 */
2828 	emode = opts.strict ? VARE_WANTRES : VARE_UNDEFERR;
2829 	(void)Var_Subst(line, SCOPE_CMDLINE, emode, &expanded_line);
2830 	/* TODO: handle errors */
2831 
2832 	/* Need a fresh list for the target nodes */
2833 	if (targets != NULL)
2834 		Lst_Free(targets);
2835 	targets = Lst_New();
2836 
2837 	ParseDependency(expanded_line);
2838 	free(expanded_line);
2839 
2840 	if (shellcmd != NULL)
2841 		ParseLine_ShellCommand(shellcmd);
2842 }
2843 
2844 static void
2845 ParseLine(char *line)
2846 {
2847 	/*
2848 	 * Lines that begin with '.' can be pretty much anything:
2849 	 *	- directives like '.include' or '.if',
2850 	 *	- suffix rules like '.c.o:',
2851 	 *	- dependencies for filenames that start with '.',
2852 	 *	- variable assignments like '.tmp=value'.
2853 	 */
2854 	if (line[0] == '.' && ParseDirective(line))
2855 		return;
2856 
2857 	if (line[0] == '\t') {
2858 		ParseLine_ShellCommand(line + 1);
2859 		return;
2860 	}
2861 
2862 #ifdef SYSVINCLUDE
2863 	if (IsSysVInclude(line)) {
2864 		/*
2865 		 * It's an S3/S5-style "include".
2866 		 */
2867 		ParseTraditionalInclude(line);
2868 		return;
2869 	}
2870 #endif
2871 
2872 #ifdef GMAKEEXPORT
2873 	if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
2874 	    strchr(line, ':') == NULL) {
2875 		/*
2876 		 * It's a Gmake "export".
2877 		 */
2878 		ParseGmakeExport(line);
2879 		return;
2880 	}
2881 #endif
2882 
2883 	if (Parse_VarAssign(line, true, SCOPE_GLOBAL))
2884 		return;
2885 
2886 	FinishDependencyGroup();
2887 
2888 	ParseDependencyLine(line);
2889 }
2890 
2891 /*
2892  * Parse a top-level makefile, incorporating its content into the global
2893  * dependency graph.
2894  */
2895 void
2896 Parse_File(const char *name, int fd)
2897 {
2898 	char *line;
2899 	Buffer buf;
2900 
2901 	buf = loadfile(name, fd != -1 ? fd : STDIN_FILENO);
2902 	if (fd != -1)
2903 		(void)close(fd);
2904 
2905 	assert(targets == NULL);
2906 
2907 	Parse_PushInput(name, 1, 0, buf, NULL);
2908 
2909 	do {
2910 		while ((line = ReadHighLevelLine()) != NULL) {
2911 			DEBUG2(PARSE, "Parsing line %u: %s\n",
2912 			    CurFile()->lineno, line);
2913 			ParseLine(line);
2914 		}
2915 		/* Reached EOF, but it may be just EOF of an include file. */
2916 	} while (ParseEOF());
2917 
2918 	FinishDependencyGroup();
2919 
2920 	if (parseErrors != 0) {
2921 		(void)fflush(stdout);
2922 		(void)fprintf(stderr,
2923 		    "%s: Fatal errors encountered -- cannot continue\n",
2924 		    progname);
2925 		PrintOnError(NULL, "");
2926 		exit(1);
2927 	}
2928 }
2929 
2930 /* Initialize the parsing module. */
2931 void
2932 Parse_Init(void)
2933 {
2934 	mainNode = NULL;
2935 	parseIncPath = SearchPath_New();
2936 	sysIncPath = SearchPath_New();
2937 	defSysIncPath = SearchPath_New();
2938 	Vector_Init(&includes, sizeof(IncludedFile));
2939 }
2940 
2941 /* Clean up the parsing module. */
2942 void
2943 Parse_End(void)
2944 {
2945 #ifdef CLEANUP
2946 	Lst_DoneCall(&targCmds, free);
2947 	assert(targets == NULL);
2948 	SearchPath_Free(defSysIncPath);
2949 	SearchPath_Free(sysIncPath);
2950 	SearchPath_Free(parseIncPath);
2951 	assert(includes.len == 0);
2952 	Vector_Done(&includes);
2953 #endif
2954 }
2955 
2956 
2957 /*
2958  * Return a list containing the single main target to create.
2959  * If no such target exists, we Punt with an obnoxious error message.
2960  */
2961 void
2962 Parse_MainName(GNodeList *mainList)
2963 {
2964 	if (mainNode == NULL)
2965 		Punt("no target to make.");
2966 
2967 	Lst_Append(mainList, mainNode);
2968 	if (mainNode->type & OP_DOUBLEDEP)
2969 		Lst_AppendAll(mainList, &mainNode->cohorts);
2970 
2971 	Global_Append(".TARGETS", mainNode->name);
2972 }
2973 
2974 int
2975 Parse_NumErrors(void)
2976 {
2977 	return parseErrors;
2978 }
2979