xref: /freebsd/contrib/bmake/parse.c (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 /*	$NetBSD: parse.c,v 1.574 2021/12/12 15:44:41 rillig 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  * The directories for the .include "..." directive are kept in
78  * 'parseIncPath', while those for .include <...> are kept in 'sysIncPath'.
79  * The targets currently being defined are kept in 'targets'.
80  *
81  * Interface:
82  *	Parse_Init	Initialize the module
83  *
84  *	Parse_End	Clean up the module
85  *
86  *	Parse_File	Parse a top-level makefile.  Included files are
87  *			handled by IncludeFile instead.
88  *
89  *	Parse_IsVar	Return true if the given line is a variable
90  *			assignment. Used by MainParseArgs to determine if
91  *			an argument is a target or a variable assignment.
92  *			Used internally for pretty much the same thing.
93  *
94  *	Parse_Error	Report a parse error, a warning or an informational
95  *			message.
96  *
97  *	Parse_MainName	Returns a list of the main target to create.
98  */
99 
100 #include <sys/types.h>
101 #include <sys/stat.h>
102 #include <errno.h>
103 #include <stdarg.h>
104 
105 #include "make.h"
106 
107 #ifdef HAVE_STDINT_H
108 #include <stdint.h>
109 #endif
110 
111 #ifdef HAVE_MMAP
112 #include <sys/mman.h>
113 
114 #ifndef MAP_COPY
115 #define MAP_COPY MAP_PRIVATE
116 #endif
117 #ifndef MAP_FILE
118 #define MAP_FILE 0
119 #endif
120 #endif
121 
122 #include "dir.h"
123 #include "job.h"
124 #include "pathnames.h"
125 
126 /*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
127 MAKE_RCSID("$NetBSD: parse.c,v 1.574 2021/12/12 15:44:41 rillig Exp $");
128 
129 /* types and constants */
130 
131 /*
132  * Structure for a file being read ("included file")
133  */
134 typedef struct IFile {
135 	char *fname;		/* name of file (relative? absolute?) */
136 	bool fromForLoop;	/* simulated .include by the .for loop */
137 	int lineno;		/* current line number in file */
138 	int first_lineno;	/* line number of start of text */
139 	unsigned int cond_depth; /* 'if' nesting when file opened */
140 	bool depending;	/* state of doing_depend on EOF */
141 
142 	/*
143 	 * The buffer from which the file's content is read.  The buffer
144 	 * always ends with '\n', the buffer is not null-terminated, that is,
145 	 * buf_end[0] is already out of bounds.
146 	 */
147 	char *buf_freeIt;
148 	char *buf_ptr;		/* next char to be read */
149 	char *buf_end;		/* buf_end[-1] == '\n' */
150 
151 	/* Function to read more data, with a single opaque argument. */
152 	ReadMoreProc readMore;
153 	void *readMoreArg;
154 
155 	struct loadedfile *lf;	/* loadedfile object, if any */
156 } IFile;
157 
158 /*
159  * Tokens for target attributes
160  */
161 typedef enum ParseSpecial {
162 	SP_ATTRIBUTE,	/* Generic attribute */
163 	SP_BEGIN,	/* .BEGIN */
164 	SP_DEFAULT,	/* .DEFAULT */
165 	SP_DELETE_ON_ERROR, /* .DELETE_ON_ERROR */
166 	SP_END,		/* .END */
167 	SP_ERROR,	/* .ERROR */
168 	SP_IGNORE,	/* .IGNORE */
169 	SP_INCLUDES,	/* .INCLUDES; not mentioned in the manual page */
170 	SP_INTERRUPT,	/* .INTERRUPT */
171 	SP_LIBS,	/* .LIBS; not mentioned in the manual page */
172 	/* .MAIN and we don't have anything user-specified to make */
173 	SP_MAIN,
174 	SP_META,	/* .META */
175 	SP_MFLAGS,	/* .MFLAGS or .MAKEFLAGS */
176 	SP_NOMETA,	/* .NOMETA */
177 	SP_NOMETA_CMP,	/* .NOMETA_CMP */
178 	SP_NOPATH,	/* .NOPATH */
179 	SP_NOT,		/* Not special */
180 	SP_NOTPARALLEL,	/* .NOTPARALLEL or .NO_PARALLEL */
181 	SP_NULL,	/* .NULL; not mentioned in the manual page */
182 	SP_OBJDIR,	/* .OBJDIR */
183 	SP_ORDER,	/* .ORDER */
184 	SP_PARALLEL,	/* .PARALLEL; not mentioned in the manual page */
185 	SP_PATH,	/* .PATH or .PATH.suffix */
186 	SP_PHONY,	/* .PHONY */
187 #ifdef POSIX
188 	SP_POSIX,	/* .POSIX; not mentioned in the manual page */
189 #endif
190 	SP_PRECIOUS,	/* .PRECIOUS */
191 	SP_SHELL,	/* .SHELL */
192 	SP_SILENT,	/* .SILENT */
193 	SP_SINGLESHELL,	/* .SINGLESHELL; not mentioned in the manual page */
194 	SP_STALE,	/* .STALE */
195 	SP_SUFFIXES,	/* .SUFFIXES */
196 	SP_WAIT		/* .WAIT */
197 } ParseSpecial;
198 
199 typedef List SearchPathList;
200 typedef ListNode SearchPathListNode;
201 
202 /* result data */
203 
204 /*
205  * The main target to create. This is the first target on the first
206  * dependency line in the first makefile.
207  */
208 static GNode *mainNode;
209 
210 /* eval state */
211 
212 /*
213  * During parsing, the targets from the left-hand side of the currently
214  * active dependency line, or NULL if the current line does not belong to a
215  * dependency line, for example because it is a variable assignment.
216  *
217  * See unit-tests/deptgt.mk, keyword "parse.c:targets".
218  */
219 static GNodeList *targets;
220 
221 #ifdef CLEANUP
222 /*
223  * All shell commands for all targets, in no particular order and possibly
224  * with duplicates.  Kept in a separate list since the commands from .USE or
225  * .USEBEFORE nodes are shared with other GNodes, thereby giving up the
226  * easily understandable ownership over the allocated strings.
227  */
228 static StringList targCmds = LST_INIT;
229 #endif
230 
231 /*
232  * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
233  * seen, then set to each successive source on the line.
234  */
235 static GNode *order_pred;
236 
237 /* parser state */
238 
239 /* number of fatal errors */
240 static int parseErrors = 0;
241 
242 /*
243  * Variables for doing includes
244  */
245 
246 /*
247  * The include chain of makefiles.  At index 0 is the top-level makefile from
248  * the command line, followed by the included files or .for loops, up to and
249  * including the current file.
250  *
251  * See PrintStackTrace for how to interpret the data.
252  */
253 static Vector /* of IFile */ includes;
254 
255 static IFile *
256 GetInclude(size_t i)
257 {
258 	return Vector_Get(&includes, i);
259 }
260 
261 /* The file that is currently being read. */
262 static IFile *
263 CurFile(void)
264 {
265 	return GetInclude(includes.len - 1);
266 }
267 
268 /* include paths */
269 SearchPath *parseIncPath;	/* directories for "..." includes */
270 SearchPath *sysIncPath;		/* directories for <...> includes */
271 SearchPath *defSysIncPath;	/* default for sysIncPath */
272 
273 /* parser tables */
274 
275 /*
276  * The parseKeywords table is searched using binary search when deciding
277  * if a target or source is special. The 'spec' field is the ParseSpecial
278  * type of the keyword (SP_NOT if the keyword isn't special as a target) while
279  * the 'op' field is the operator to apply to the list of targets if the
280  * keyword is used as a source ("0" if the keyword isn't special as a source)
281  */
282 static const struct {
283 	const char name[17];	/* Name of keyword */
284 	ParseSpecial spec;	/* Type when used as a target */
285 	GNodeType op;		/* Operator when used as a source */
286 } parseKeywords[] = {
287     { ".BEGIN",		SP_BEGIN,	OP_NONE },
288     { ".DEFAULT",	SP_DEFAULT,	OP_NONE },
289     { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, OP_NONE },
290     { ".END",		SP_END,		OP_NONE },
291     { ".ERROR",		SP_ERROR,	OP_NONE },
292     { ".EXEC",		SP_ATTRIBUTE,	OP_EXEC },
293     { ".IGNORE",	SP_IGNORE,	OP_IGNORE },
294     { ".INCLUDES",	SP_INCLUDES,	OP_NONE },
295     { ".INTERRUPT",	SP_INTERRUPT,	OP_NONE },
296     { ".INVISIBLE",	SP_ATTRIBUTE,	OP_INVISIBLE },
297     { ".JOIN",		SP_ATTRIBUTE,	OP_JOIN },
298     { ".LIBS",		SP_LIBS,	OP_NONE },
299     { ".MADE",		SP_ATTRIBUTE,	OP_MADE },
300     { ".MAIN",		SP_MAIN,	OP_NONE },
301     { ".MAKE",		SP_ATTRIBUTE,	OP_MAKE },
302     { ".MAKEFLAGS",	SP_MFLAGS,	OP_NONE },
303     { ".META",		SP_META,	OP_META },
304     { ".MFLAGS",	SP_MFLAGS,	OP_NONE },
305     { ".NOMETA",	SP_NOMETA,	OP_NOMETA },
306     { ".NOMETA_CMP",	SP_NOMETA_CMP,	OP_NOMETA_CMP },
307     { ".NOPATH",	SP_NOPATH,	OP_NOPATH },
308     { ".NOTMAIN",	SP_ATTRIBUTE,	OP_NOTMAIN },
309     { ".NOTPARALLEL",	SP_NOTPARALLEL,	OP_NONE },
310     { ".NO_PARALLEL",	SP_NOTPARALLEL,	OP_NONE },
311     { ".NULL",		SP_NULL,	OP_NONE },
312     { ".OBJDIR",	SP_OBJDIR,	OP_NONE },
313     { ".OPTIONAL",	SP_ATTRIBUTE,	OP_OPTIONAL },
314     { ".ORDER",		SP_ORDER,	OP_NONE },
315     { ".PARALLEL",	SP_PARALLEL,	OP_NONE },
316     { ".PATH",		SP_PATH,	OP_NONE },
317     { ".PHONY",		SP_PHONY,	OP_PHONY },
318 #ifdef POSIX
319     { ".POSIX",		SP_POSIX,	OP_NONE },
320 #endif
321     { ".PRECIOUS",	SP_PRECIOUS,	OP_PRECIOUS },
322     { ".RECURSIVE",	SP_ATTRIBUTE,	OP_MAKE },
323     { ".SHELL",		SP_SHELL,	OP_NONE },
324     { ".SILENT",	SP_SILENT,	OP_SILENT },
325     { ".SINGLESHELL",	SP_SINGLESHELL,	OP_NONE },
326     { ".STALE",		SP_STALE,	OP_NONE },
327     { ".SUFFIXES",	SP_SUFFIXES,	OP_NONE },
328     { ".USE",		SP_ATTRIBUTE,	OP_USE },
329     { ".USEBEFORE",	SP_ATTRIBUTE,	OP_USEBEFORE },
330     { ".WAIT",		SP_WAIT,	OP_NONE },
331 };
332 
333 /* file loader */
334 
335 struct loadedfile {
336 	char *buf;		/* contents buffer */
337 	size_t len;		/* length of contents */
338 	bool used;		/* XXX: have we used the data yet */
339 };
340 
341 /* XXX: What is the lifetime of the path? Who manages the memory? */
342 static struct loadedfile *
343 loadedfile_create(char *buf, size_t buflen)
344 {
345 	struct loadedfile *lf;
346 
347 	lf = bmake_malloc(sizeof *lf);
348 	lf->buf = buf;
349 	lf->len = buflen;
350 	lf->used = false;
351 	return lf;
352 }
353 
354 static void
355 loadedfile_destroy(struct loadedfile *lf)
356 {
357 	free(lf->buf);
358 	free(lf);
359 }
360 
361 /*
362  * readMore() operation for loadedfile, as needed by the weird and twisted
363  * logic below. Once that's cleaned up, we can get rid of lf->used.
364  */
365 static char *
366 loadedfile_readMore(void *x, size_t *len)
367 {
368 	struct loadedfile *lf = x;
369 
370 	if (lf->used)
371 		return NULL;
372 
373 	lf->used = true;
374 	*len = lf->len;
375 	return lf->buf;
376 }
377 
378 /*
379  * Try to get the size of a file.
380  */
381 static bool
382 load_getsize(int fd, size_t *ret)
383 {
384 	struct stat st;
385 
386 	if (fstat(fd, &st) < 0)
387 		return false;
388 
389 	if (!S_ISREG(st.st_mode))
390 		return false;
391 
392 	/*
393 	 * st_size is an off_t, which is 64 bits signed; *ret is
394 	 * size_t, which might be 32 bits unsigned or 64 bits
395 	 * unsigned. Rather than being elaborate, just punt on
396 	 * files that are more than 1 GiB. We should never
397 	 * see a makefile that size in practice.
398 	 *
399 	 * While we're at it reject negative sizes too, just in case.
400 	 */
401 	if (st.st_size < 0 || st.st_size > 0x3fffffff)
402 		return false;
403 
404 	*ret = (size_t)st.st_size;
405 	return true;
406 }
407 
408 /*
409  * Read in a file.
410  *
411  * Until the path search logic can be moved under here instead of
412  * being in the caller in another source file, we need to have the fd
413  * passed in already open. Bleh.
414  *
415  * If the path is NULL, use stdin.
416  */
417 static struct loadedfile *
418 loadfile(const char *path, int fd)
419 {
420 	ssize_t n;
421 	Buffer buf;
422 	size_t filesize;
423 
424 
425 	if (path == NULL) {
426 		assert(fd == -1);
427 		fd = STDIN_FILENO;
428 	}
429 
430 	if (load_getsize(fd, &filesize)) {
431 		/*
432 		 * Avoid resizing the buffer later for no reason.
433 		 *
434 		 * At the same time leave space for adding a final '\n',
435 		 * just in case it is missing in the file.
436 		 */
437 		filesize++;
438 	} else
439 		filesize = 1024;
440 	Buf_InitSize(&buf, filesize);
441 
442 	for (;;) {
443 		assert(buf.len <= buf.cap);
444 		if (buf.len == buf.cap) {
445 			if (buf.cap > 0x1fffffff) {
446 				errno = EFBIG;
447 				Error("%s: file too large", path);
448 				exit(2); /* Not 1 so -q can distinguish error */
449 			}
450 			Buf_Expand(&buf);
451 		}
452 		assert(buf.len < buf.cap);
453 		n = read(fd, buf.data + buf.len, buf.cap - buf.len);
454 		if (n < 0) {
455 			Error("%s: read error: %s", path, strerror(errno));
456 			exit(2);	/* Not 1 so -q can distinguish error */
457 		}
458 		if (n == 0)
459 			break;
460 
461 		buf.len += (size_t)n;
462 	}
463 	assert(buf.len <= buf.cap);
464 
465 	if (!Buf_EndsWith(&buf, '\n'))
466 		Buf_AddByte(&buf, '\n');
467 
468 	if (path != NULL)
469 		close(fd);
470 
471 	{
472 		struct loadedfile *lf = loadedfile_create(buf.data, buf.len);
473 		Buf_DoneData(&buf);
474 		return lf;
475 	}
476 }
477 
478 static void
479 PrintStackTrace(void)
480 {
481 	const IFile *entries;
482 	size_t i, n;
483 
484 	if (!(DEBUG(PARSE)))
485 		return;
486 
487 	entries = GetInclude(0);
488 	n = includes.len;
489 	if (n == 0)
490 		return;
491 	n--;			/* This entry is already in the diagnostic. */
492 
493 	/*
494 	 * For the IFiles with fromForLoop, lineno seems to be sorted
495 	 * backwards.  This is because lineno is the number of completely
496 	 * parsed lines, which for a .for loop is right after the
497 	 * corresponding .endfor.  The intuitive line number comes from
498 	 * first_lineno instead, which points at the start of the .for loop.
499 	 *
500 	 * To make the stack trace intuitive, the entry below each chain of
501 	 * .for loop entries must be ignored completely since neither its
502 	 * lineno nor its first_lineno is useful.  Instead, the topmost of
503 	 * each chain of .for loop entries needs to be printed twice, once
504 	 * with its first_lineno and once with its lineno.
505 	 */
506 
507 	for (i = n; i-- > 0;) {
508 		const IFile *entry = entries + i;
509 		const char *fname = entry->fname;
510 		bool printLineno;
511 		char dirbuf[MAXPATHLEN + 1];
512 
513 		if (fname[0] != '/' && strcmp(fname, "(stdin)") != 0)
514 			fname = realpath(fname, dirbuf);
515 
516 		printLineno = !entry->fromForLoop;
517 		if (i + 1 < n && entries[i + 1].fromForLoop == printLineno)
518 			printLineno = entry->fromForLoop;
519 
520 		if (printLineno)
521 			debug_printf("\tin .include from %s:%d\n",
522 			    fname, entry->lineno);
523 		if (entry->fromForLoop)
524 			debug_printf("\tin .for loop from %s:%d\n",
525 			    fname, entry->first_lineno);
526 	}
527 }
528 
529 /* Check if the current character is escaped on the current line. */
530 static bool
531 ParseIsEscaped(const char *line, const char *c)
532 {
533 	bool active = false;
534 	for (;;) {
535 		if (line == c)
536 			return active;
537 		if (*--c != '\\')
538 			return active;
539 		active = !active;
540 	}
541 }
542 
543 /*
544  * Add the filename and lineno to the GNode so that we remember where it
545  * was first defined.
546  */
547 static void
548 RememberLocation(GNode *gn)
549 {
550 	IFile *curFile = CurFile();
551 	gn->fname = curFile->fname;
552 	gn->lineno = curFile->lineno;
553 }
554 
555 /*
556  * Look in the table of keywords for one matching the given string.
557  * Return the index of the keyword, or -1 if it isn't there.
558  */
559 static int
560 ParseFindKeyword(const char *str)
561 {
562 	int start = 0;
563 	int end = sizeof parseKeywords / sizeof parseKeywords[0] - 1;
564 
565 	do {
566 		int curr = start + (end - start) / 2;
567 		int diff = strcmp(str, parseKeywords[curr].name);
568 
569 		if (diff == 0)
570 			return curr;
571 		if (diff < 0)
572 			end = curr - 1;
573 		else
574 			start = curr + 1;
575 	} while (start <= end);
576 
577 	return -1;
578 }
579 
580 static void
581 PrintLocation(FILE *f, const char *fname, size_t lineno)
582 {
583 	char dirbuf[MAXPATHLEN + 1];
584 	FStr dir, base;
585 
586 	if (*fname == '/' || strcmp(fname, "(stdin)") == 0) {
587 		(void)fprintf(f, "\"%s\" line %u: ", fname, (unsigned)lineno);
588 		return;
589 	}
590 
591 	/* Find out which makefile is the culprit.
592 	 * We try ${.PARSEDIR} and apply realpath(3) if not absolute. */
593 
594 	dir = Var_Value(SCOPE_GLOBAL, ".PARSEDIR");
595 	if (dir.str == NULL)
596 		dir.str = ".";
597 	if (dir.str[0] != '/')
598 		dir.str = realpath(dir.str, dirbuf);
599 
600 	base = Var_Value(SCOPE_GLOBAL, ".PARSEFILE");
601 	if (base.str == NULL)
602 		base.str = str_basename(fname);
603 
604 	(void)fprintf(f, "\"%s/%s\" line %u: ",
605 	    dir.str, base.str, (unsigned)lineno);
606 
607 	FStr_Done(&base);
608 	FStr_Done(&dir);
609 }
610 
611 static void
612 ParseVErrorInternal(FILE *f, const char *fname, size_t lineno,
613 		    ParseErrorLevel type, const char *fmt, va_list ap)
614 {
615 	static bool fatal_warning_error_printed = false;
616 
617 	(void)fprintf(f, "%s: ", progname);
618 
619 	if (fname != NULL)
620 		PrintLocation(f, fname, lineno);
621 	if (type == PARSE_WARNING)
622 		(void)fprintf(f, "warning: ");
623 	(void)vfprintf(f, fmt, ap);
624 	(void)fprintf(f, "\n");
625 	(void)fflush(f);
626 
627 	if (type == PARSE_INFO)
628 		goto print_stack_trace;
629 	if (type == PARSE_WARNING && !opts.parseWarnFatal)
630 		goto print_stack_trace;
631 	parseErrors++;
632 	if (type == PARSE_WARNING && !fatal_warning_error_printed) {
633 		Error("parsing warnings being treated as errors");
634 		fatal_warning_error_printed = true;
635 	}
636 
637 print_stack_trace:
638 	PrintStackTrace();
639 }
640 
641 static void
642 ParseErrorInternal(const char *fname, size_t lineno,
643 		   ParseErrorLevel type, const char *fmt, ...)
644 {
645 	va_list ap;
646 
647 	(void)fflush(stdout);
648 	va_start(ap, fmt);
649 	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
650 	va_end(ap);
651 
652 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
653 		va_start(ap, fmt);
654 		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
655 		    fmt, ap);
656 		va_end(ap);
657 	}
658 }
659 
660 /*
661  * Print a parse error message, including location information.
662  *
663  * If the level is PARSE_FATAL, continue parsing until the end of the
664  * current top-level makefile, then exit (see Parse_File).
665  *
666  * Fmt is given without a trailing newline.
667  */
668 void
669 Parse_Error(ParseErrorLevel type, const char *fmt, ...)
670 {
671 	va_list ap;
672 	const char *fname;
673 	size_t lineno;
674 
675 	if (includes.len == 0) {
676 		fname = NULL;
677 		lineno = 0;
678 	} else {
679 		IFile *curFile = CurFile();
680 		fname = curFile->fname;
681 		lineno = (size_t)curFile->lineno;
682 	}
683 
684 	va_start(ap, fmt);
685 	(void)fflush(stdout);
686 	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
687 	va_end(ap);
688 
689 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
690 		va_start(ap, fmt);
691 		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
692 		    fmt, ap);
693 		va_end(ap);
694 	}
695 }
696 
697 
698 /*
699  * Parse and handle an .info, .warning or .error directive.
700  * For an .error directive, immediately exit.
701  */
702 static void
703 ParseMessage(ParseErrorLevel level, const char *levelName, const char *umsg)
704 {
705 	char *xmsg;
706 
707 	if (umsg[0] == '\0') {
708 		Parse_Error(PARSE_FATAL, "Missing argument for \".%s\"",
709 		    levelName);
710 		return;
711 	}
712 
713 	(void)Var_Subst(umsg, SCOPE_CMDLINE, VARE_WANTRES, &xmsg);
714 	/* TODO: handle errors */
715 
716 	Parse_Error(level, "%s", xmsg);
717 	free(xmsg);
718 
719 	if (level == PARSE_FATAL) {
720 		PrintOnError(NULL, NULL);
721 		exit(1);
722 	}
723 }
724 
725 /*
726  * Add the child to the parent's children.
727  *
728  * Additionally, add the parent to the child's parents, but only if the
729  * target is not special.  An example for such a special target is .END,
730  * which does not need to be informed once the child target has been made.
731  */
732 static void
733 LinkSource(GNode *pgn, GNode *cgn, bool isSpecial)
734 {
735 	if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(&pgn->cohorts))
736 		pgn = pgn->cohorts.last->datum;
737 
738 	Lst_Append(&pgn->children, cgn);
739 	pgn->unmade++;
740 
741 	/* Special targets like .END don't need any children. */
742 	if (!isSpecial)
743 		Lst_Append(&cgn->parents, pgn);
744 
745 	if (DEBUG(PARSE)) {
746 		debug_printf("# %s: added child %s - %s\n",
747 		    __func__, pgn->name, cgn->name);
748 		Targ_PrintNode(pgn, 0);
749 		Targ_PrintNode(cgn, 0);
750 	}
751 }
752 
753 /* Add the node to each target from the current dependency group. */
754 static void
755 LinkToTargets(GNode *gn, bool isSpecial)
756 {
757 	GNodeListNode *ln;
758 
759 	for (ln = targets->first; ln != NULL; ln = ln->next)
760 		LinkSource(ln->datum, gn, isSpecial);
761 }
762 
763 static bool
764 TryApplyDependencyOperator(GNode *gn, GNodeType op)
765 {
766 	/*
767 	 * If the node occurred on the left-hand side of a dependency and the
768 	 * operator also defines a dependency, they must match.
769 	 */
770 	if ((op & OP_OPMASK) && (gn->type & OP_OPMASK) &&
771 	    ((op & OP_OPMASK) != (gn->type & OP_OPMASK))) {
772 		Parse_Error(PARSE_FATAL, "Inconsistent operator for %s",
773 		    gn->name);
774 		return false;
775 	}
776 
777 	if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
778 		/*
779 		 * If the node was of the left-hand side of a '::' operator,
780 		 * we need to create a new instance of it for the children
781 		 * and commands on this dependency line since each of these
782 		 * dependency groups has its own attributes and commands,
783 		 * separate from the others.
784 		 *
785 		 * The new instance is placed on the 'cohorts' list of the
786 		 * initial one (note the initial one is not on its own
787 		 * cohorts list) and the new instance is linked to all
788 		 * parents of the initial instance.
789 		 */
790 		GNode *cohort;
791 
792 		/*
793 		 * Propagate copied bits to the initial node.  They'll be
794 		 * propagated back to the rest of the cohorts later.
795 		 */
796 		gn->type |= op & ~OP_OPMASK;
797 
798 		cohort = Targ_NewInternalNode(gn->name);
799 		if (doing_depend)
800 			RememberLocation(cohort);
801 		/*
802 		 * Make the cohort invisible as well to avoid duplicating it
803 		 * into other variables. True, parents of this target won't
804 		 * tend to do anything with their local variables, but better
805 		 * safe than sorry.
806 		 *
807 		 * (I think this is pointless now, since the relevant list
808 		 * traversals will no longer see this node anyway. -mycroft)
809 		 */
810 		cohort->type = op | OP_INVISIBLE;
811 		Lst_Append(&gn->cohorts, cohort);
812 		cohort->centurion = gn;
813 		gn->unmade_cohorts++;
814 		snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
815 		    (unsigned int)gn->unmade_cohorts % 1000000);
816 	} else {
817 		/*
818 		 * We don't want to nuke any previous flags (whatever they
819 		 * were) so we just OR the new operator into the old.
820 		 */
821 		gn->type |= op;
822 	}
823 
824 	return true;
825 }
826 
827 static void
828 ApplyDependencyOperator(GNodeType op)
829 {
830 	GNodeListNode *ln;
831 
832 	for (ln = targets->first; ln != NULL; ln = ln->next)
833 		if (!TryApplyDependencyOperator(ln->datum, op))
834 			break;
835 }
836 
837 /*
838  * We add a .WAIT node in the dependency list. After any dynamic dependencies
839  * (and filename globbing) have happened, it is given a dependency on each
840  * previous child, back until the previous .WAIT node. The next child won't
841  * be scheduled until the .WAIT node is built.
842  *
843  * We give each .WAIT node a unique name (mainly for diagnostics).
844  */
845 static void
846 ParseDependencySourceWait(bool isSpecial)
847 {
848 	static int wait_number = 0;
849 	char wait_src[16];
850 	GNode *gn;
851 
852 	snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
853 	gn = Targ_NewInternalNode(wait_src);
854 	if (doing_depend)
855 		RememberLocation(gn);
856 	gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
857 	LinkToTargets(gn, isSpecial);
858 
859 }
860 
861 static bool
862 ParseDependencySourceKeyword(const char *src, ParseSpecial specType)
863 {
864 	int keywd;
865 	GNodeType op;
866 
867 	if (*src != '.' || !ch_isupper(src[1]))
868 		return false;
869 
870 	keywd = ParseFindKeyword(src);
871 	if (keywd == -1)
872 		return false;
873 
874 	op = parseKeywords[keywd].op;
875 	if (op != OP_NONE) {
876 		ApplyDependencyOperator(op);
877 		return true;
878 	}
879 	if (parseKeywords[keywd].spec == SP_WAIT) {
880 		ParseDependencySourceWait(specType != SP_NOT);
881 		return true;
882 	}
883 	return false;
884 }
885 
886 static void
887 ParseDependencySourceMain(const char *src)
888 {
889 	/*
890 	 * In a line like ".MAIN: source1 source2", add all sources to the
891 	 * list of things to create, but only if the user didn't specify a
892 	 * target on the command line and .MAIN occurs for the first time.
893 	 *
894 	 * See ParseDependencyTargetSpecial, branch SP_MAIN.
895 	 * See unit-tests/cond-func-make-main.mk.
896 	 */
897 	Lst_Append(&opts.create, bmake_strdup(src));
898 	/*
899 	 * Add the name to the .TARGETS variable as well, so the user can
900 	 * employ that, if desired.
901 	 */
902 	Global_Append(".TARGETS", src);
903 }
904 
905 static void
906 ParseDependencySourceOrder(const char *src)
907 {
908 	GNode *gn;
909 	/*
910 	 * Create proper predecessor/successor links between the previous
911 	 * source and the current one.
912 	 */
913 	gn = Targ_GetNode(src);
914 	if (doing_depend)
915 		RememberLocation(gn);
916 	if (order_pred != NULL) {
917 		Lst_Append(&order_pred->order_succ, gn);
918 		Lst_Append(&gn->order_pred, order_pred);
919 		if (DEBUG(PARSE)) {
920 			debug_printf("# %s: added Order dependency %s - %s\n",
921 			    __func__, order_pred->name, gn->name);
922 			Targ_PrintNode(order_pred, 0);
923 			Targ_PrintNode(gn, 0);
924 		}
925 	}
926 	/*
927 	 * The current source now becomes the predecessor for the next one.
928 	 */
929 	order_pred = gn;
930 }
931 
932 static void
933 ParseDependencySourceOther(const char *src, GNodeType tOp,
934 			   ParseSpecial specType)
935 {
936 	GNode *gn;
937 
938 	/*
939 	 * The source is not an attribute, so find/create a node for it.
940 	 * After that, apply any operator to it from a special target or
941 	 * link it to its parents, as appropriate.
942 	 *
943 	 * In the case of a source that was the object of a '::' operator,
944 	 * the attribute is applied to all of its instances (as kept in
945 	 * the 'cohorts' list of the node) or all the cohorts are linked
946 	 * to all the targets.
947 	 */
948 
949 	/* Find/create the 'src' node and attach to all targets */
950 	gn = Targ_GetNode(src);
951 	if (doing_depend)
952 		RememberLocation(gn);
953 	if (tOp != OP_NONE)
954 		gn->type |= tOp;
955 	else
956 		LinkToTargets(gn, specType != SP_NOT);
957 }
958 
959 /*
960  * Given the name of a source in a dependency line, figure out if it is an
961  * attribute (such as .SILENT) and apply it to the targets if it is. Else
962  * decide if there is some attribute which should be applied *to* the source
963  * because of some special target (such as .PHONY) and apply it if so.
964  * Otherwise, make the source a child of the targets in the list 'targets'.
965  *
966  * Input:
967  *	tOp		operator (if any) from special targets
968  *	src		name of the source to handle
969  */
970 static void
971 ParseDependencySource(GNodeType tOp, const char *src, ParseSpecial specType)
972 {
973 	if (ParseDependencySourceKeyword(src, specType))
974 		return;
975 
976 	if (specType == SP_MAIN)
977 		ParseDependencySourceMain(src);
978 	else if (specType == SP_ORDER)
979 		ParseDependencySourceOrder(src);
980 	else
981 		ParseDependencySourceOther(src, tOp, specType);
982 }
983 
984 /*
985  * If we have yet to decide on a main target to make, in the absence of any
986  * user input, we want the first target on the first dependency line that is
987  * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made.
988  */
989 static void
990 FindMainTarget(void)
991 {
992 	GNodeListNode *ln;
993 
994 	if (mainNode != NULL)
995 		return;
996 
997 	for (ln = targets->first; ln != NULL; ln = ln->next) {
998 		GNode *gn = ln->datum;
999 		if (!(gn->type & OP_NOTARGET)) {
1000 			DEBUG1(MAKE, "Setting main node to \"%s\"\n", gn->name);
1001 			mainNode = gn;
1002 			Targ_SetMain(gn);
1003 			return;
1004 		}
1005 	}
1006 }
1007 
1008 /*
1009  * We got to the end of the line while we were still looking at targets.
1010  *
1011  * Ending a dependency line without an operator is a Bozo no-no.  As a
1012  * heuristic, this is also often triggered by undetected conflicts from
1013  * cvs/rcs merges.
1014  */
1015 static void
1016 ParseErrorNoDependency(const char *lstart)
1017 {
1018 	if ((strncmp(lstart, "<<<<<<", 6) == 0) ||
1019 	    (strncmp(lstart, "======", 6) == 0) ||
1020 	    (strncmp(lstart, ">>>>>>", 6) == 0))
1021 		Parse_Error(PARSE_FATAL,
1022 		    "Makefile appears to contain unresolved CVS/RCS/??? merge conflicts");
1023 	else if (lstart[0] == '.') {
1024 		const char *dirstart = lstart + 1;
1025 		const char *dirend;
1026 		cpp_skip_whitespace(&dirstart);
1027 		dirend = dirstart;
1028 		while (ch_isalnum(*dirend) || *dirend == '-')
1029 			dirend++;
1030 		Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
1031 		    (int)(dirend - dirstart), dirstart);
1032 	} else
1033 		Parse_Error(PARSE_FATAL, "Invalid line type");
1034 }
1035 
1036 static void
1037 ParseDependencyTargetWord(const char **pp, const char *lstart)
1038 {
1039 	const char *cp = *pp;
1040 
1041 	while (*cp != '\0') {
1042 		if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' ||
1043 		     *cp == '(') &&
1044 		    !ParseIsEscaped(lstart, cp))
1045 			break;
1046 
1047 		if (*cp == '$') {
1048 			/*
1049 			 * Must be a dynamic source (would have been expanded
1050 			 * otherwise), so call the Var module to parse the
1051 			 * puppy so we can safely advance beyond it.
1052 			 *
1053 			 * There should be no errors in this, as they would
1054 			 * have been discovered in the initial Var_Subst and
1055 			 * we wouldn't be here.
1056 			 */
1057 			const char *nested_p = cp;
1058 			FStr nested_val;
1059 
1060 			(void)Var_Parse(&nested_p, SCOPE_CMDLINE,
1061 			    VARE_PARSE_ONLY, &nested_val);
1062 			/* TODO: handle errors */
1063 			FStr_Done(&nested_val);
1064 			cp += nested_p - cp;
1065 		} else
1066 			cp++;
1067 	}
1068 
1069 	*pp = cp;
1070 }
1071 
1072 /*
1073  * Handle special targets like .PATH, .DEFAULT, .BEGIN, .ORDER.
1074  *
1075  * See the tests deptgt-*.mk.
1076  */
1077 static void
1078 ParseDependencyTargetSpecial(ParseSpecial *inout_specType,
1079 			     const char *targetName,
1080 			     SearchPathList **inout_paths)
1081 {
1082 	switch (*inout_specType) {
1083 	case SP_PATH:
1084 		if (*inout_paths == NULL)
1085 			*inout_paths = Lst_New();
1086 		Lst_Append(*inout_paths, &dirSearchPath);
1087 		break;
1088 	case SP_MAIN:
1089 		/*
1090 		 * Allow targets from the command line to override the
1091 		 * .MAIN node.
1092 		 */
1093 		if (!Lst_IsEmpty(&opts.create))
1094 			*inout_specType = SP_NOT;
1095 		break;
1096 	case SP_BEGIN:
1097 	case SP_END:
1098 	case SP_STALE:
1099 	case SP_ERROR:
1100 	case SP_INTERRUPT: {
1101 		GNode *gn = Targ_GetNode(targetName);
1102 		if (doing_depend)
1103 			RememberLocation(gn);
1104 		gn->type |= OP_NOTMAIN | OP_SPECIAL;
1105 		Lst_Append(targets, gn);
1106 		break;
1107 	}
1108 	case SP_DEFAULT: {
1109 		/*
1110 		 * Need to create a node to hang commands on, but we don't
1111 		 * want it in the graph, nor do we want it to be the Main
1112 		 * Target. We claim the node is a transformation rule to make
1113 		 * life easier later, when we'll use Make_HandleUse to
1114 		 * actually apply the .DEFAULT commands.
1115 		 */
1116 		GNode *gn = GNode_New(".DEFAULT");
1117 		gn->type |= OP_NOTMAIN | OP_TRANSFORM;
1118 		Lst_Append(targets, gn);
1119 		defaultNode = gn;
1120 		break;
1121 	}
1122 	case SP_DELETE_ON_ERROR:
1123 		deleteOnError = true;
1124 		break;
1125 	case SP_NOTPARALLEL:
1126 		opts.maxJobs = 1;
1127 		break;
1128 	case SP_SINGLESHELL:
1129 		opts.compatMake = true;
1130 		break;
1131 	case SP_ORDER:
1132 		order_pred = NULL;
1133 		break;
1134 	default:
1135 		break;
1136 	}
1137 }
1138 
1139 /*
1140  * .PATH<suffix> has to be handled specially.
1141  * Call on the suffix module to give us a path to modify.
1142  */
1143 static bool
1144 ParseDependencyTargetPath(const char *suffixName,
1145 			  SearchPathList **inout_paths)
1146 {
1147 	SearchPath *path;
1148 
1149 	path = Suff_GetPath(suffixName);
1150 	if (path == NULL) {
1151 		Parse_Error(PARSE_FATAL,
1152 		    "Suffix '%s' not defined (yet)", suffixName);
1153 		return false;
1154 	}
1155 
1156 	if (*inout_paths == NULL)
1157 		*inout_paths = Lst_New();
1158 	Lst_Append(*inout_paths, path);
1159 
1160 	return true;
1161 }
1162 
1163 /*
1164  * See if it's a special target and if so set specType to match it.
1165  */
1166 static bool
1167 ParseDependencyTarget(const char *targetName,
1168 		      ParseSpecial *inout_specType,
1169 		      GNodeType *out_tOp, SearchPathList **inout_paths)
1170 {
1171 	int keywd;
1172 
1173 	if (!(targetName[0] == '.' && ch_isupper(targetName[1])))
1174 		return true;
1175 
1176 	/*
1177 	 * See if the target is a special target that must have it
1178 	 * or its sources handled specially.
1179 	 */
1180 	keywd = ParseFindKeyword(targetName);
1181 	if (keywd != -1) {
1182 		if (*inout_specType == SP_PATH &&
1183 		    parseKeywords[keywd].spec != SP_PATH) {
1184 			Parse_Error(PARSE_FATAL, "Mismatched special targets");
1185 			return false;
1186 		}
1187 
1188 		*inout_specType = parseKeywords[keywd].spec;
1189 		*out_tOp = parseKeywords[keywd].op;
1190 
1191 		ParseDependencyTargetSpecial(inout_specType, targetName,
1192 		    inout_paths);
1193 
1194 	} else if (strncmp(targetName, ".PATH", 5) == 0) {
1195 		*inout_specType = SP_PATH;
1196 		if (!ParseDependencyTargetPath(targetName + 5, inout_paths))
1197 			return false;
1198 	}
1199 	return true;
1200 }
1201 
1202 static void
1203 ParseDependencyTargetMundane(char *targetName, StringList *curTargs)
1204 {
1205 	if (Dir_HasWildcards(targetName)) {
1206 		/*
1207 		 * Targets are to be sought only in the current directory,
1208 		 * so create an empty path for the thing. Note we need to
1209 		 * use Dir_Destroy in the destruction of the path as the
1210 		 * Dir module could have added a directory to the path...
1211 		 */
1212 		SearchPath *emptyPath = SearchPath_New();
1213 
1214 		SearchPath_Expand(emptyPath, targetName, curTargs);
1215 
1216 		SearchPath_Free(emptyPath);
1217 	} else {
1218 		/*
1219 		 * No wildcards, but we want to avoid code duplication,
1220 		 * so create a list with the word on it.
1221 		 */
1222 		Lst_Append(curTargs, targetName);
1223 	}
1224 
1225 	/* Apply the targets. */
1226 
1227 	while (!Lst_IsEmpty(curTargs)) {
1228 		char *targName = Lst_Dequeue(curTargs);
1229 		GNode *gn = Suff_IsTransform(targName)
1230 		    ? Suff_AddTransform(targName)
1231 		    : Targ_GetNode(targName);
1232 		if (doing_depend)
1233 			RememberLocation(gn);
1234 
1235 		Lst_Append(targets, gn);
1236 	}
1237 }
1238 
1239 static void
1240 ParseDependencyTargetExtraWarn(char **pp, const char *lstart)
1241 {
1242 	bool warning = false;
1243 	char *cp = *pp;
1244 
1245 	while (*cp != '\0') {
1246 		if (!ParseIsEscaped(lstart, cp) && (*cp == '!' || *cp == ':'))
1247 			break;
1248 		if (ParseIsEscaped(lstart, cp) || (*cp != ' ' && *cp != '\t'))
1249 			warning = true;
1250 		cp++;
1251 	}
1252 	if (warning)
1253 		Parse_Error(PARSE_WARNING, "Extra target ignored");
1254 
1255 	*pp = cp;
1256 }
1257 
1258 static void
1259 ParseDependencyCheckSpec(ParseSpecial specType)
1260 {
1261 	switch (specType) {
1262 	default:
1263 		Parse_Error(PARSE_WARNING,
1264 		    "Special and mundane targets don't mix. "
1265 		    "Mundane ones ignored");
1266 		break;
1267 	case SP_DEFAULT:
1268 	case SP_STALE:
1269 	case SP_BEGIN:
1270 	case SP_END:
1271 	case SP_ERROR:
1272 	case SP_INTERRUPT:
1273 		/*
1274 		 * These create nodes on which to hang commands, so targets
1275 		 * shouldn't be empty.
1276 		 */
1277 	case SP_NOT:
1278 		/* Nothing special here -- targets can be empty if it wants. */
1279 		break;
1280 	}
1281 }
1282 
1283 /*
1284  * In a dependency line like 'targets: sources' or 'targets! sources', parse
1285  * the operator ':', '::' or '!' from between the targets and the sources.
1286  */
1287 static bool
1288 ParseDependencyOp(char **pp, const char *lstart, GNodeType *out_op)
1289 {
1290 	const char *cp = *pp;
1291 
1292 	if (*cp == '!') {
1293 		*out_op = OP_FORCE;
1294 		(*pp)++;
1295 		return true;
1296 	}
1297 
1298 	if (*cp == ':') {
1299 		if (cp[1] == ':') {
1300 			*out_op = OP_DOUBLEDEP;
1301 			(*pp) += 2;
1302 		} else {
1303 			*out_op = OP_DEPENDS;
1304 			(*pp)++;
1305 		}
1306 		return true;
1307 	}
1308 
1309 	{
1310 		const char *msg = lstart[0] == '.'
1311 		    ? "Unknown directive" : "Missing dependency operator";
1312 		Parse_Error(PARSE_FATAL, "%s", msg);
1313 		return false;
1314 	}
1315 }
1316 
1317 static void
1318 ClearPaths(SearchPathList *paths)
1319 {
1320 	if (paths != NULL) {
1321 		SearchPathListNode *ln;
1322 		for (ln = paths->first; ln != NULL; ln = ln->next)
1323 			SearchPath_Clear(ln->datum);
1324 	}
1325 
1326 	Dir_SetPATH();
1327 }
1328 
1329 /*
1330  * Several special targets take different actions if present with no
1331  * sources:
1332  *	a .SUFFIXES line with no sources clears out all old suffixes
1333  *	a .PRECIOUS line makes all targets precious
1334  *	a .IGNORE line ignores errors for all targets
1335  *	a .SILENT line creates silence when making all targets
1336  *	a .PATH removes all directories from the search path(s).
1337  */
1338 static void
1339 ParseDependencySourcesEmpty(ParseSpecial specType, SearchPathList *paths)
1340 {
1341 	switch (specType) {
1342 	case SP_SUFFIXES:
1343 		Suff_ClearSuffixes();
1344 		break;
1345 	case SP_PRECIOUS:
1346 		allPrecious = true;
1347 		break;
1348 	case SP_IGNORE:
1349 		opts.ignoreErrors = true;
1350 		break;
1351 	case SP_SILENT:
1352 		opts.beSilent = true;
1353 		break;
1354 	case SP_PATH:
1355 		ClearPaths(paths);
1356 		break;
1357 #ifdef POSIX
1358 	case SP_POSIX:
1359 		Global_Set("%POSIX", "1003.2");
1360 		break;
1361 #endif
1362 	default:
1363 		break;
1364 	}
1365 }
1366 
1367 static void
1368 AddToPaths(const char *dir, SearchPathList *paths)
1369 {
1370 	if (paths != NULL) {
1371 		SearchPathListNode *ln;
1372 		for (ln = paths->first; ln != NULL; ln = ln->next)
1373 			(void)SearchPath_Add(ln->datum, dir);
1374 	}
1375 }
1376 
1377 /*
1378  * If the target was one that doesn't take files as its sources
1379  * but takes something like suffixes, we take each
1380  * space-separated word on the line as a something and deal
1381  * with it accordingly.
1382  *
1383  * If the target was .SUFFIXES, we take each source as a
1384  * suffix and add it to the list of suffixes maintained by the
1385  * Suff module.
1386  *
1387  * If the target was a .PATH, we add the source as a directory
1388  * to search on the search path.
1389  *
1390  * If it was .INCLUDES, the source is taken to be the suffix of
1391  * files which will be #included and whose search path should
1392  * be present in the .INCLUDES variable.
1393  *
1394  * If it was .LIBS, the source is taken to be the suffix of
1395  * files which are considered libraries and whose search path
1396  * should be present in the .LIBS variable.
1397  *
1398  * If it was .NULL, the source is the suffix to use when a file
1399  * has no valid suffix.
1400  *
1401  * If it was .OBJDIR, the source is a new definition for .OBJDIR,
1402  * and will cause make to do a new chdir to that path.
1403  */
1404 static void
1405 ParseDependencySourceSpecial(ParseSpecial specType, char *word,
1406 			     SearchPathList *paths)
1407 {
1408 	switch (specType) {
1409 	case SP_SUFFIXES:
1410 		Suff_AddSuffix(word, &mainNode);
1411 		break;
1412 	case SP_PATH:
1413 		AddToPaths(word, paths);
1414 		break;
1415 	case SP_INCLUDES:
1416 		Suff_AddInclude(word);
1417 		break;
1418 	case SP_LIBS:
1419 		Suff_AddLib(word);
1420 		break;
1421 	case SP_NULL:
1422 		Suff_SetNull(word);
1423 		break;
1424 	case SP_OBJDIR:
1425 		Main_SetObjdir(false, "%s", word);
1426 		break;
1427 	default:
1428 		break;
1429 	}
1430 }
1431 
1432 static bool
1433 ParseDependencyTargets(char **inout_cp,
1434 		       char **inout_line,
1435 		       const char *lstart,
1436 		       ParseSpecial *inout_specType,
1437 		       GNodeType *inout_tOp,
1438 		       SearchPathList **inout_paths,
1439 		       StringList *curTargs)
1440 {
1441 	char *cp;
1442 	char *tgt = *inout_line;
1443 	char savec;
1444 	const char *p;
1445 
1446 	for (;;) {
1447 		/*
1448 		 * Here LINE points to the beginning of the next word, and
1449 		 * LSTART points to the actual beginning of the line.
1450 		 */
1451 
1452 		/* Find the end of the next word. */
1453 		cp = tgt;
1454 		p = cp;
1455 		ParseDependencyTargetWord(&p, lstart);
1456 		cp += p - cp;
1457 
1458 		/*
1459 		 * If the word is followed by a left parenthesis, it's the
1460 		 * name of an object file inside an archive (ar file).
1461 		 */
1462 		if (!ParseIsEscaped(lstart, cp) && *cp == '(') {
1463 			/*
1464 			 * Archives must be handled specially to make sure the
1465 			 * OP_ARCHV flag is set in their 'type' field, for one
1466 			 * thing, and because things like "archive(file1.o
1467 			 * file2.o file3.o)" are permissible.
1468 			 *
1469 			 * Arch_ParseArchive will set 'line' to be the first
1470 			 * non-blank after the archive-spec. It creates/finds
1471 			 * nodes for the members and places them on the given
1472 			 * list, returning true if all went well and false if
1473 			 * there was an error in the specification. On error,
1474 			 * line should remain untouched.
1475 			 */
1476 			if (!Arch_ParseArchive(&tgt, targets, SCOPE_CMDLINE)) {
1477 				Parse_Error(PARSE_FATAL,
1478 				    "Error in archive specification: \"%s\"",
1479 				    tgt);
1480 				return false;
1481 			}
1482 
1483 			cp = tgt;
1484 			continue;
1485 		}
1486 
1487 		if (*cp == '\0') {
1488 			ParseErrorNoDependency(lstart);
1489 			return false;
1490 		}
1491 
1492 		/* Insert a null terminator. */
1493 		savec = *cp;
1494 		*cp = '\0';
1495 
1496 		if (!ParseDependencyTarget(tgt, inout_specType, inout_tOp,
1497 		    inout_paths))
1498 			return false;
1499 
1500 		/*
1501 		 * Have word in line. Get or create its node and stick it at
1502 		 * the end of the targets list
1503 		 */
1504 		if (*inout_specType == SP_NOT && *tgt != '\0')
1505 			ParseDependencyTargetMundane(tgt, curTargs);
1506 		else if (*inout_specType == SP_PATH && *tgt != '.' &&
1507 			 *tgt != '\0')
1508 			Parse_Error(PARSE_WARNING, "Extra target (%s) ignored",
1509 			    tgt);
1510 
1511 		/* Don't need the inserted null terminator any more. */
1512 		*cp = savec;
1513 
1514 		/*
1515 		 * If it is a special type and not .PATH, it's the only target
1516 		 * we allow on this line.
1517 		 */
1518 		if (*inout_specType != SP_NOT && *inout_specType != SP_PATH)
1519 			ParseDependencyTargetExtraWarn(&cp, lstart);
1520 		else
1521 			pp_skip_whitespace(&cp);
1522 
1523 		tgt = cp;
1524 		if (*tgt == '\0')
1525 			break;
1526 		if ((*tgt == '!' || *tgt == ':') &&
1527 		    !ParseIsEscaped(lstart, tgt))
1528 			break;
1529 	}
1530 
1531 	*inout_cp = cp;
1532 	*inout_line = tgt;
1533 	return true;
1534 }
1535 
1536 static void
1537 ParseDependencySourcesSpecial(char *start, char *end,
1538 			      ParseSpecial specType, SearchPathList *paths)
1539 {
1540 	char savec;
1541 
1542 	while (*start != '\0') {
1543 		while (*end != '\0' && !ch_isspace(*end))
1544 			end++;
1545 		savec = *end;
1546 		*end = '\0';
1547 		ParseDependencySourceSpecial(specType, start, paths);
1548 		*end = savec;
1549 		if (savec != '\0')
1550 			end++;
1551 		pp_skip_whitespace(&end);
1552 		start = end;
1553 	}
1554 }
1555 
1556 static bool
1557 ParseDependencySourcesMundane(char *start, char *end,
1558 			      ParseSpecial specType, GNodeType tOp)
1559 {
1560 	while (*start != '\0') {
1561 		/*
1562 		 * The targets take real sources, so we must beware of archive
1563 		 * specifications (i.e. things with left parentheses in them)
1564 		 * and handle them accordingly.
1565 		 */
1566 		for (; *end != '\0' && !ch_isspace(*end); end++) {
1567 			if (*end == '(' && end > start && end[-1] != '$') {
1568 				/*
1569 				 * Only stop for a left parenthesis if it
1570 				 * isn't at the start of a word (that'll be
1571 				 * for variable changes later) and isn't
1572 				 * preceded by a dollar sign (a dynamic
1573 				 * source).
1574 				 */
1575 				break;
1576 			}
1577 		}
1578 
1579 		if (*end == '(') {
1580 			GNodeList sources = LST_INIT;
1581 			if (!Arch_ParseArchive(&start, &sources,
1582 			    SCOPE_CMDLINE)) {
1583 				Parse_Error(PARSE_FATAL,
1584 				    "Error in source archive spec \"%s\"",
1585 				    start);
1586 				return false;
1587 			}
1588 
1589 			while (!Lst_IsEmpty(&sources)) {
1590 				GNode *gn = Lst_Dequeue(&sources);
1591 				ParseDependencySource(tOp, gn->name, specType);
1592 			}
1593 			Lst_Done(&sources);
1594 			end = start;
1595 		} else {
1596 			if (*end != '\0') {
1597 				*end = '\0';
1598 				end++;
1599 			}
1600 
1601 			ParseDependencySource(tOp, start, specType);
1602 		}
1603 		pp_skip_whitespace(&end);
1604 		start = end;
1605 	}
1606 	return true;
1607 }
1608 
1609 /*
1610  * In a dependency line like 'targets: sources', parse the sources.
1611  *
1612  * See the tests depsrc-*.mk.
1613  */
1614 static void
1615 ParseDependencySources(char *line, char *cp, GNodeType tOp,
1616 		       ParseSpecial specType, SearchPathList **inout_paths)
1617 {
1618 	if (line[0] == '\0') {
1619 		ParseDependencySourcesEmpty(specType, *inout_paths);
1620 	} else if (specType == SP_MFLAGS) {
1621 		Main_ParseArgLine(line);
1622 		/*
1623 		 * Set the initial character to a null-character so the loop
1624 		 * to get sources won't get anything.
1625 		 */
1626 		*line = '\0';
1627 	} else if (specType == SP_SHELL) {
1628 		if (!Job_ParseShell(line)) {
1629 			Parse_Error(PARSE_FATAL,
1630 			    "improper shell specification");
1631 			return;
1632 		}
1633 		*line = '\0';
1634 	} else if (specType == SP_NOTPARALLEL || specType == SP_SINGLESHELL ||
1635 		   specType == SP_DELETE_ON_ERROR) {
1636 		*line = '\0';
1637 	}
1638 
1639 	/* Now go for the sources. */
1640 	if (specType == SP_SUFFIXES || specType == SP_PATH ||
1641 	    specType == SP_INCLUDES || specType == SP_LIBS ||
1642 	    specType == SP_NULL || specType == SP_OBJDIR) {
1643 		ParseDependencySourcesSpecial(line, cp, specType,
1644 		    *inout_paths);
1645 		if (*inout_paths != NULL) {
1646 			Lst_Free(*inout_paths);
1647 			*inout_paths = NULL;
1648 		}
1649 		if (specType == SP_PATH)
1650 			Dir_SetPATH();
1651 	} else {
1652 		assert(*inout_paths == NULL);
1653 		if (!ParseDependencySourcesMundane(line, cp, specType, tOp))
1654 			return;
1655 	}
1656 
1657 	FindMainTarget();
1658 }
1659 
1660 /*
1661  * Parse a dependency line consisting of targets, followed by a dependency
1662  * operator, optionally followed by sources.
1663  *
1664  * The nodes of the sources are linked as children to the nodes of the
1665  * targets. Nodes are created as necessary.
1666  *
1667  * The operator is applied to each node in the global 'targets' list,
1668  * which is where the nodes found for the targets are kept, by means of
1669  * the ParseOp function.
1670  *
1671  * The sources are parsed in much the same way as the targets, except
1672  * that they are expanded using the wildcarding scheme of the C-Shell,
1673  * and a target is created for each expanded word. Each of the resulting
1674  * nodes is then linked to each of the targets as one of its children.
1675  *
1676  * Certain targets and sources such as .PHONY or .PRECIOUS are handled
1677  * specially. These are the ones detailed by the specType variable.
1678  *
1679  * The storing of transformation rules such as '.c.o' is also taken care of
1680  * here. A target is recognized as a transformation rule by calling
1681  * Suff_IsTransform. If it is a transformation rule, its node is gotten
1682  * from the suffix module via Suff_AddTransform rather than the standard
1683  * Targ_FindNode in the target module.
1684  *
1685  * Upon return, the value of the line is unspecified.
1686  */
1687 static void
1688 ParseDependency(char *line)
1689 {
1690 	char *cp;		/* our current position */
1691 	GNodeType op;		/* the operator on the line */
1692 	SearchPathList *paths;	/* search paths to alter when parsing
1693 				 * a list of .PATH targets */
1694 	GNodeType tOp;		/* operator from special target */
1695 	/* target names to be found and added to the targets list */
1696 	StringList curTargs = LST_INIT;
1697 	char *lstart = line;
1698 
1699 	/*
1700 	 * specType contains the SPECial TYPE of the current target. It is
1701 	 * SP_NOT if the target is unspecial. If it *is* special, however, the
1702 	 * children are linked as children of the parent but not vice versa.
1703 	 */
1704 	ParseSpecial specType = SP_NOT;
1705 
1706 	DEBUG1(PARSE, "ParseDependency(%s)\n", line);
1707 	tOp = OP_NONE;
1708 
1709 	paths = NULL;
1710 
1711 	/*
1712 	 * First, grind through the targets.
1713 	 */
1714 	/* XXX: don't use 'line' as an iterator variable */
1715 	if (!ParseDependencyTargets(&cp, &line, lstart, &specType, &tOp,
1716 	    &paths, &curTargs))
1717 		goto out;
1718 
1719 	/*
1720 	 * Don't need the list of target names anymore.
1721 	 * The targets themselves are now in the global variable 'targets'.
1722 	 */
1723 	Lst_Done(&curTargs);
1724 	Lst_Init(&curTargs);
1725 
1726 	if (!Lst_IsEmpty(targets))
1727 		ParseDependencyCheckSpec(specType);
1728 
1729 	/*
1730 	 * Have now parsed all the target names. Must parse the operator next.
1731 	 */
1732 	if (!ParseDependencyOp(&cp, lstart, &op))
1733 		goto out;
1734 
1735 	/*
1736 	 * Apply the operator to the target. This is how we remember which
1737 	 * operator a target was defined with. It fails if the operator
1738 	 * used isn't consistent across all references.
1739 	 */
1740 	ApplyDependencyOperator(op);
1741 
1742 	/*
1743 	 * Onward to the sources.
1744 	 *
1745 	 * LINE will now point to the first source word, if any, or the
1746 	 * end of the string if not.
1747 	 */
1748 	pp_skip_whitespace(&cp);
1749 	line = cp;		/* XXX: 'line' is an inappropriate name */
1750 
1751 	ParseDependencySources(line, cp, tOp, specType, &paths);
1752 
1753 out:
1754 	if (paths != NULL)
1755 		Lst_Free(paths);
1756 	Lst_Done(&curTargs);
1757 }
1758 
1759 typedef struct VarAssignParsed {
1760 	const char *nameStart;	/* unexpanded */
1761 	const char *nameEnd;	/* before operator adjustment */
1762 	const char *eq;		/* the '=' of the assignment operator */
1763 } VarAssignParsed;
1764 
1765 /*
1766  * Determine the assignment operator and adjust the end of the variable
1767  * name accordingly.
1768  */
1769 static void
1770 AdjustVarassignOp(const VarAssignParsed *pvar, const char *value,
1771 		  VarAssign *out_var)
1772 {
1773 	const char *op = pvar->eq;
1774 	const char *const name = pvar->nameStart;
1775 	VarAssignOp type;
1776 
1777 	if (op > name && op[-1] == '+') {
1778 		type = VAR_APPEND;
1779 		op--;
1780 
1781 	} else if (op > name && op[-1] == '?') {
1782 		op--;
1783 		type = VAR_DEFAULT;
1784 
1785 	} else if (op > name && op[-1] == ':') {
1786 		op--;
1787 		type = VAR_SUBST;
1788 
1789 	} else if (op > name && op[-1] == '!') {
1790 		op--;
1791 		type = VAR_SHELL;
1792 
1793 	} else {
1794 		type = VAR_NORMAL;
1795 #ifdef SUNSHCMD
1796 		while (op > name && ch_isspace(op[-1]))
1797 			op--;
1798 
1799 		if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' &&
1800 		    op[-1] == 'h') {
1801 			type = VAR_SHELL;
1802 			op -= 3;
1803 		}
1804 #endif
1805 	}
1806 
1807 	{
1808 		const char *nameEnd = pvar->nameEnd < op ? pvar->nameEnd : op;
1809 		out_var->varname = bmake_strsedup(pvar->nameStart, nameEnd);
1810 		out_var->op = type;
1811 		out_var->value = value;
1812 	}
1813 }
1814 
1815 /*
1816  * Parse a variable assignment, consisting of a single-word variable name,
1817  * optional whitespace, an assignment operator, optional whitespace and the
1818  * variable value.
1819  *
1820  * Note: There is a lexical ambiguity with assignment modifier characters
1821  * in variable names. This routine interprets the character before the =
1822  * as a modifier. Therefore, an assignment like
1823  *	C++=/usr/bin/CC
1824  * is interpreted as "C+ +=" instead of "C++ =".
1825  *
1826  * Used for both lines in a file and command line arguments.
1827  */
1828 bool
1829 Parse_IsVar(const char *p, VarAssign *out_var)
1830 {
1831 	VarAssignParsed pvar;
1832 	const char *firstSpace = NULL;
1833 	int level = 0;
1834 
1835 	cpp_skip_hspace(&p);	/* Skip to variable name */
1836 
1837 	/*
1838 	 * During parsing, the '+' of the '+=' operator is initially parsed
1839 	 * as part of the variable name.  It is later corrected, as is the
1840 	 * ':sh' modifier. Of these two (nameEnd and op), the earlier one
1841 	 * determines the actual end of the variable name.
1842 	 */
1843 	pvar.nameStart = p;
1844 #ifdef CLEANUP
1845 	pvar.nameEnd = NULL;
1846 	pvar.eq = NULL;
1847 #endif
1848 
1849 	/*
1850 	 * Scan for one of the assignment operators outside a variable
1851 	 * expansion.
1852 	 */
1853 	while (*p != '\0') {
1854 		char ch = *p++;
1855 		if (ch == '(' || ch == '{') {
1856 			level++;
1857 			continue;
1858 		}
1859 		if (ch == ')' || ch == '}') {
1860 			level--;
1861 			continue;
1862 		}
1863 
1864 		if (level != 0)
1865 			continue;
1866 
1867 		if (ch == ' ' || ch == '\t')
1868 			if (firstSpace == NULL)
1869 				firstSpace = p - 1;
1870 		while (ch == ' ' || ch == '\t')
1871 			ch = *p++;
1872 
1873 #ifdef SUNSHCMD
1874 		if (ch == ':' && p[0] == 's' && p[1] == 'h') {
1875 			p += 2;
1876 			continue;
1877 		}
1878 #endif
1879 		if (ch == '=') {
1880 			pvar.eq = p - 1;
1881 			pvar.nameEnd = firstSpace != NULL ? firstSpace : p - 1;
1882 			cpp_skip_whitespace(&p);
1883 			AdjustVarassignOp(&pvar, p, out_var);
1884 			return true;
1885 		}
1886 		if (*p == '=' &&
1887 		    (ch == '+' || ch == ':' || ch == '?' || ch == '!')) {
1888 			pvar.eq = p;
1889 			pvar.nameEnd = firstSpace != NULL ? firstSpace : p;
1890 			p++;
1891 			cpp_skip_whitespace(&p);
1892 			AdjustVarassignOp(&pvar, p, out_var);
1893 			return true;
1894 		}
1895 		if (firstSpace != NULL)
1896 			return false;
1897 	}
1898 
1899 	return false;
1900 }
1901 
1902 /*
1903  * Check for syntax errors such as unclosed expressions or unknown modifiers.
1904  */
1905 static void
1906 VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *scope)
1907 {
1908 	if (opts.strict) {
1909 		if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
1910 			char *expandedValue;
1911 
1912 			(void)Var_Subst(uvalue, scope, VARE_PARSE_ONLY,
1913 			    &expandedValue);
1914 			/* TODO: handle errors */
1915 			free(expandedValue);
1916 		}
1917 	}
1918 }
1919 
1920 static void
1921 VarAssign_EvalSubst(GNode *scope, const char *name, const char *uvalue,
1922 		    FStr *out_avalue)
1923 {
1924 	char *evalue;
1925 
1926 	/*
1927 	 * make sure that we set the variable the first time to nothing
1928 	 * so that it gets substituted.
1929 	 *
1930 	 * TODO: Add a test that demonstrates why this code is needed,
1931 	 *  apart from making the debug log longer.
1932 	 */
1933 	if (!Var_ExistsExpand(scope, name))
1934 		Var_SetExpand(scope, name, "");
1935 
1936 	(void)Var_Subst(uvalue, scope, VARE_KEEP_DOLLAR_UNDEF, &evalue);
1937 	/* TODO: handle errors */
1938 
1939 	Var_SetExpand(scope, name, evalue);
1940 
1941 	*out_avalue = FStr_InitOwn(evalue);
1942 }
1943 
1944 static void
1945 VarAssign_EvalShell(const char *name, const char *uvalue, GNode *scope,
1946 		    FStr *out_avalue)
1947 {
1948 	FStr cmd;
1949 	const char *errfmt;
1950 	char *cmdOut;
1951 
1952 	cmd = FStr_InitRefer(uvalue);
1953 	if (strchr(cmd.str, '$') != NULL) {
1954 		char *expanded;
1955 		(void)Var_Subst(cmd.str, SCOPE_CMDLINE, VARE_UNDEFERR,
1956 		    &expanded);
1957 		/* TODO: handle errors */
1958 		cmd = FStr_InitOwn(expanded);
1959 	}
1960 
1961 	cmdOut = Cmd_Exec(cmd.str, &errfmt);
1962 	Var_SetExpand(scope, name, cmdOut);
1963 	*out_avalue = FStr_InitOwn(cmdOut);
1964 
1965 	if (errfmt != NULL)
1966 		Parse_Error(PARSE_WARNING, errfmt, cmd.str);
1967 
1968 	FStr_Done(&cmd);
1969 }
1970 
1971 /*
1972  * Perform a variable assignment.
1973  *
1974  * The actual value of the variable is returned in *out_true_avalue.
1975  * Especially for VAR_SUBST and VAR_SHELL this can differ from the literal
1976  * value.
1977  *
1978  * Return whether the assignment was actually performed, which is usually
1979  * the case.  It is only skipped if the operator is '?=' and the variable
1980  * already exists.
1981  */
1982 static bool
1983 VarAssign_Eval(const char *name, VarAssignOp op, const char *uvalue,
1984 	       GNode *scope, FStr *out_true_avalue)
1985 {
1986 	FStr avalue = FStr_InitRefer(uvalue);
1987 
1988 	if (op == VAR_APPEND)
1989 		Var_AppendExpand(scope, name, uvalue);
1990 	else if (op == VAR_SUBST)
1991 		VarAssign_EvalSubst(scope, name, uvalue, &avalue);
1992 	else if (op == VAR_SHELL)
1993 		VarAssign_EvalShell(name, uvalue, scope, &avalue);
1994 	else {
1995 		if (op == VAR_DEFAULT && Var_ExistsExpand(scope, name))
1996 			return false;
1997 
1998 		/* Normal assignment -- just do it. */
1999 		Var_SetExpand(scope, name, uvalue);
2000 	}
2001 
2002 	*out_true_avalue = avalue;
2003 	return true;
2004 }
2005 
2006 static void
2007 VarAssignSpecial(const char *name, const char *avalue)
2008 {
2009 	if (strcmp(name, MAKEOVERRIDES) == 0)
2010 		Main_ExportMAKEFLAGS(false); /* re-export MAKEFLAGS */
2011 	else if (strcmp(name, ".CURDIR") == 0) {
2012 		/*
2013 		 * Someone is being (too?) clever...
2014 		 * Let's pretend they know what they are doing and
2015 		 * re-initialize the 'cur' CachedDir.
2016 		 */
2017 		Dir_InitCur(avalue);
2018 		Dir_SetPATH();
2019 	} else if (strcmp(name, MAKE_JOB_PREFIX) == 0)
2020 		Job_SetPrefix();
2021 	else if (strcmp(name, MAKE_EXPORTED) == 0)
2022 		Var_ExportVars(avalue);
2023 }
2024 
2025 /* Perform the variable variable assignment in the given scope. */
2026 void
2027 Parse_Var(VarAssign *var, GNode *scope)
2028 {
2029 	FStr avalue;	/* actual value (maybe expanded) */
2030 
2031 	VarCheckSyntax(var->op, var->value, scope);
2032 	if (VarAssign_Eval(var->varname, var->op, var->value, scope, &avalue)) {
2033 		VarAssignSpecial(var->varname, avalue.str);
2034 		FStr_Done(&avalue);
2035 	}
2036 
2037 	free(var->varname);
2038 }
2039 
2040 
2041 /*
2042  * See if the command possibly calls a sub-make by using the variable
2043  * expressions ${.MAKE}, ${MAKE} or the plain word "make".
2044  */
2045 static bool
2046 MaybeSubMake(const char *cmd)
2047 {
2048 	const char *start;
2049 
2050 	for (start = cmd; *start != '\0'; start++) {
2051 		const char *p = start;
2052 		char endc;
2053 
2054 		/* XXX: What if progname != "make"? */
2055 		if (p[0] == 'm' && p[1] == 'a' && p[2] == 'k' && p[3] == 'e')
2056 			if (start == cmd || !ch_isalnum(p[-1]))
2057 				if (!ch_isalnum(p[4]))
2058 					return true;
2059 
2060 		if (*p != '$')
2061 			continue;
2062 		p++;
2063 
2064 		if (*p == '{')
2065 			endc = '}';
2066 		else if (*p == '(')
2067 			endc = ')';
2068 		else
2069 			continue;
2070 		p++;
2071 
2072 		if (*p == '.')	/* Accept either ${.MAKE} or ${MAKE}. */
2073 			p++;
2074 
2075 		if (p[0] == 'M' && p[1] == 'A' && p[2] == 'K' && p[3] == 'E')
2076 			if (p[4] == endc)
2077 				return true;
2078 	}
2079 	return false;
2080 }
2081 
2082 /*
2083  * Append the command to the target node.
2084  *
2085  * The node may be marked as a submake node if the command is determined to
2086  * be that.
2087  */
2088 static void
2089 ParseAddCmd(GNode *gn, char *cmd)
2090 {
2091 	/* Add to last (ie current) cohort for :: targets */
2092 	if ((gn->type & OP_DOUBLEDEP) && gn->cohorts.last != NULL)
2093 		gn = gn->cohorts.last->datum;
2094 
2095 	/* if target already supplied, ignore commands */
2096 	if (!(gn->type & OP_HAS_COMMANDS)) {
2097 		Lst_Append(&gn->commands, cmd);
2098 		if (MaybeSubMake(cmd))
2099 			gn->type |= OP_SUBMAKE;
2100 		RememberLocation(gn);
2101 	} else {
2102 #if 0
2103 		/* XXX: We cannot do this until we fix the tree */
2104 		Lst_Append(&gn->commands, cmd);
2105 		Parse_Error(PARSE_WARNING,
2106 		    "overriding commands for target \"%s\"; "
2107 		    "previous commands defined at %s: %d ignored",
2108 		    gn->name, gn->fname, gn->lineno);
2109 #else
2110 		Parse_Error(PARSE_WARNING,
2111 		    "duplicate script for target \"%s\" ignored",
2112 		    gn->name);
2113 		ParseErrorInternal(gn->fname, (size_t)gn->lineno, PARSE_WARNING,
2114 		    "using previous script for \"%s\" defined here",
2115 		    gn->name);
2116 #endif
2117 	}
2118 }
2119 
2120 /*
2121  * Add a directory to the path searched for included makefiles bracketed
2122  * by double-quotes.
2123  */
2124 void
2125 Parse_AddIncludeDir(const char *dir)
2126 {
2127 	(void)SearchPath_Add(parseIncPath, dir);
2128 }
2129 
2130 /*
2131  * Handle one of the .[-ds]include directives by remembering the current file
2132  * and pushing the included file on the stack.  After the included file has
2133  * finished, parsing continues with the including file; see Parse_PushInput
2134  * and ParseEOF.
2135  *
2136  * System includes are looked up in sysIncPath, any other includes are looked
2137  * up in the parsedir and then in the directories specified by the -I command
2138  * line options.
2139  */
2140 static void
2141 IncludeFile(const char *file, bool isSystem, bool depinc, bool silent)
2142 {
2143 	struct loadedfile *lf;
2144 	char *fullname;		/* full pathname of file */
2145 	char *newName;
2146 	char *slash, *incdir;
2147 	int fd;
2148 	int i;
2149 
2150 	fullname = file[0] == '/' ? bmake_strdup(file) : NULL;
2151 
2152 	if (fullname == NULL && !isSystem) {
2153 		/*
2154 		 * Include files contained in double-quotes are first searched
2155 		 * relative to the including file's location. We don't want to
2156 		 * cd there, of course, so we just tack on the old file's
2157 		 * leading path components and call Dir_FindFile to see if
2158 		 * we can locate the file.
2159 		 */
2160 
2161 		incdir = bmake_strdup(CurFile()->fname);
2162 		slash = strrchr(incdir, '/');
2163 		if (slash != NULL) {
2164 			*slash = '\0';
2165 			/*
2166 			 * Now do lexical processing of leading "../" on the
2167 			 * filename.
2168 			 */
2169 			for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
2170 				slash = strrchr(incdir + 1, '/');
2171 				if (slash == NULL || strcmp(slash, "/..") == 0)
2172 					break;
2173 				*slash = '\0';
2174 			}
2175 			newName = str_concat3(incdir, "/", file + i);
2176 			fullname = Dir_FindFile(newName, parseIncPath);
2177 			if (fullname == NULL)
2178 				fullname = Dir_FindFile(newName,
2179 				    &dirSearchPath);
2180 			free(newName);
2181 		}
2182 		free(incdir);
2183 
2184 		if (fullname == NULL) {
2185 			/*
2186 			 * Makefile wasn't found in same directory as included
2187 			 * makefile.
2188 			 *
2189 			 * Search for it first on the -I search path, then on
2190 			 * the .PATH search path, if not found in a -I
2191 			 * directory. If we have a suffix-specific path, we
2192 			 * should use that.
2193 			 */
2194 			const char *suff;
2195 			SearchPath *suffPath = NULL;
2196 
2197 			if ((suff = strrchr(file, '.')) != NULL) {
2198 				suffPath = Suff_GetPath(suff);
2199 				if (suffPath != NULL)
2200 					fullname = Dir_FindFile(file, suffPath);
2201 			}
2202 			if (fullname == NULL) {
2203 				fullname = Dir_FindFile(file, parseIncPath);
2204 				if (fullname == NULL)
2205 					fullname = Dir_FindFile(file,
2206 					    &dirSearchPath);
2207 			}
2208 		}
2209 	}
2210 
2211 	/* Looking for a system file or file still not found */
2212 	if (fullname == NULL) {
2213 		/*
2214 		 * Look for it on the system path
2215 		 */
2216 		SearchPath *path = Lst_IsEmpty(&sysIncPath->dirs)
2217 		    ? defSysIncPath : sysIncPath;
2218 		fullname = Dir_FindFile(file, path);
2219 	}
2220 
2221 	if (fullname == NULL) {
2222 		if (!silent)
2223 			Parse_Error(PARSE_FATAL, "Could not find %s", file);
2224 		return;
2225 	}
2226 
2227 	/* Actually open the file... */
2228 	fd = open(fullname, O_RDONLY);
2229 	if (fd == -1) {
2230 		if (!silent)
2231 			Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
2232 		free(fullname);
2233 		return;
2234 	}
2235 
2236 	/* load it */
2237 	lf = loadfile(fullname, fd);
2238 
2239 	/* Start reading from this file next */
2240 	Parse_PushInput(fullname, 0, -1, loadedfile_readMore, lf);
2241 	CurFile()->lf = lf;
2242 	if (depinc)
2243 		doing_depend = depinc;	/* only turn it on */
2244 	/* TODO: consider free(fullname); */
2245 }
2246 
2247 /*
2248  * Parse a directive like '.include' or '.-include'.
2249  *
2250  * .include "user-makefile.mk"
2251  * .include <system-makefile.mk>
2252  */
2253 static void
2254 ParseInclude(char *directive)
2255 {
2256 	char endc;		/* '>' or '"' */
2257 	char *p;
2258 	bool silent = directive[0] != 'i';
2259 	FStr file;
2260 
2261 	p = directive + (silent ? 8 : 7);
2262 	pp_skip_hspace(&p);
2263 
2264 	if (*p != '"' && *p != '<') {
2265 		Parse_Error(PARSE_FATAL,
2266 		    ".include filename must be delimited by '\"' or '<'");
2267 		return;
2268 	}
2269 
2270 	if (*p++ == '<')
2271 		endc = '>';
2272 	else
2273 		endc = '"';
2274 	file = FStr_InitRefer(p);
2275 
2276 	/* Skip to matching delimiter */
2277 	while (*p != '\0' && *p != endc)
2278 		p++;
2279 
2280 	if (*p != endc) {
2281 		Parse_Error(PARSE_FATAL,
2282 		    "Unclosed .include filename. '%c' expected", endc);
2283 		return;
2284 	}
2285 
2286 	*p = '\0';
2287 
2288 	if (strchr(file.str, '$') != NULL) {
2289 		char *xfile;
2290 		Var_Subst(file.str, SCOPE_CMDLINE, VARE_WANTRES, &xfile);
2291 		/* TODO: handle errors */
2292 		file = FStr_InitOwn(xfile);
2293 	}
2294 
2295 	IncludeFile(file.str, endc == '>', directive[0] == 'd', silent);
2296 	FStr_Done(&file);
2297 }
2298 
2299 /*
2300  * Split filename into dirname + basename, then assign these to the
2301  * given variables.
2302  */
2303 static void
2304 SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
2305 {
2306 	const char *slash, *basename;
2307 	FStr dirname;
2308 
2309 	slash = strrchr(filename, '/');
2310 	if (slash == NULL) {
2311 		dirname = FStr_InitRefer(curdir);
2312 		basename = filename;
2313 	} else {
2314 		dirname = FStr_InitOwn(bmake_strsedup(filename, slash));
2315 		basename = slash + 1;
2316 	}
2317 
2318 	Global_Set(dirvar, dirname.str);
2319 	Global_Set(filevar, basename);
2320 
2321 	DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
2322 	    __func__, dirvar, dirname.str, filevar, basename);
2323 	FStr_Done(&dirname);
2324 }
2325 
2326 /*
2327  * Return the immediately including file.
2328  *
2329  * This is made complicated since the .for loop is implemented as a special
2330  * kind of .include; see For_Run.
2331  */
2332 static const char *
2333 GetActuallyIncludingFile(void)
2334 {
2335 	size_t i;
2336 	const IFile *incs = GetInclude(0);
2337 
2338 	for (i = includes.len; i >= 2; i--)
2339 		if (!incs[i - 1].fromForLoop)
2340 			return incs[i - 2].fname;
2341 	return NULL;
2342 }
2343 
2344 /* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
2345 static void
2346 ParseSetParseFile(const char *filename)
2347 {
2348 	const char *including;
2349 
2350 	SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");
2351 
2352 	including = GetActuallyIncludingFile();
2353 	if (including != NULL) {
2354 		SetFilenameVars(including,
2355 		    ".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
2356 	} else {
2357 		Global_Delete(".INCLUDEDFROMDIR");
2358 		Global_Delete(".INCLUDEDFROMFILE");
2359 	}
2360 }
2361 
2362 static bool
2363 StrContainsWord(const char *str, const char *word)
2364 {
2365 	size_t strLen = strlen(str);
2366 	size_t wordLen = strlen(word);
2367 	const char *p, *end;
2368 
2369 	if (strLen < wordLen)
2370 		return false;	/* str is too short to contain word */
2371 
2372 	end = str + strLen - wordLen;
2373 	for (p = str; p != NULL; p = strchr(p, ' ')) {
2374 		if (*p == ' ')
2375 			p++;
2376 		if (p > end)
2377 			return false;	/* cannot contain word */
2378 
2379 		if (memcmp(p, word, wordLen) == 0 &&
2380 		    (p[wordLen] == '\0' || p[wordLen] == ' '))
2381 			return true;
2382 	}
2383 	return false;
2384 }
2385 
2386 /*
2387  * XXX: Searching through a set of words with this linear search is
2388  * inefficient for variables that contain thousands of words.
2389  *
2390  * XXX: The paths in this list don't seem to be normalized in any way.
2391  */
2392 static bool
2393 VarContainsWord(const char *varname, const char *word)
2394 {
2395 	FStr val = Var_Value(SCOPE_GLOBAL, varname);
2396 	bool found = val.str != NULL && StrContainsWord(val.str, word);
2397 	FStr_Done(&val);
2398 	return found;
2399 }
2400 
2401 /*
2402  * Track the makefiles we read - so makefiles can set dependencies on them.
2403  * Avoid adding anything more than once.
2404  *
2405  * Time complexity: O(n) per call, in total O(n^2), where n is the number
2406  * of makefiles that have been loaded.
2407  */
2408 static void
2409 ParseTrackInput(const char *name)
2410 {
2411 	if (!VarContainsWord(MAKE_MAKEFILES, name))
2412 		Global_Append(MAKE_MAKEFILES, name);
2413 }
2414 
2415 
2416 /*
2417  * Start parsing from the given source.
2418  *
2419  * The given file is added to the includes stack.
2420  */
2421 void
2422 Parse_PushInput(const char *name, int lineno, int fd,
2423 	       ReadMoreProc readMore, void *readMoreArg)
2424 {
2425 	IFile *curFile;
2426 	char *buf;
2427 	size_t len;
2428 	bool fromForLoop = name == NULL;
2429 
2430 	if (fromForLoop)
2431 		name = CurFile()->fname;
2432 	else
2433 		ParseTrackInput(name);
2434 
2435 	DEBUG3(PARSE, "Parse_PushInput: %s %s, line %d\n",
2436 	    readMore == loadedfile_readMore ? "file" : ".for loop in",
2437 	    name, lineno);
2438 
2439 	if (fd == -1 && readMore == NULL)
2440 		/* sanity */
2441 		return;
2442 
2443 	curFile = Vector_Push(&includes);
2444 	curFile->fname = bmake_strdup(name);
2445 	curFile->fromForLoop = fromForLoop;
2446 	curFile->lineno = lineno;
2447 	curFile->first_lineno = lineno;
2448 	curFile->readMore = readMore;
2449 	curFile->readMoreArg = readMoreArg;
2450 	curFile->lf = NULL;
2451 	curFile->depending = doing_depend;	/* restore this on EOF */
2452 
2453 	assert(readMore != NULL);
2454 
2455 	/* Get first block of input data */
2456 	buf = curFile->readMore(curFile->readMoreArg, &len);
2457 	if (buf == NULL) {
2458 		/* Was all a waste of time ... */
2459 		if (curFile->fname != NULL)
2460 			free(curFile->fname);
2461 		free(curFile);
2462 		return;
2463 	}
2464 	curFile->buf_freeIt = buf;
2465 	curFile->buf_ptr = buf;
2466 	curFile->buf_end = buf + len;
2467 
2468 	curFile->cond_depth = Cond_save_depth();
2469 	ParseSetParseFile(name);
2470 }
2471 
2472 /* Check if the directive is an include directive. */
2473 static bool
2474 IsInclude(const char *dir, bool sysv)
2475 {
2476 	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
2477 		dir++;
2478 
2479 	if (strncmp(dir, "include", 7) != 0)
2480 		return false;
2481 
2482 	/* Space is not mandatory for BSD .include */
2483 	return !sysv || ch_isspace(dir[7]);
2484 }
2485 
2486 
2487 #ifdef SYSVINCLUDE
2488 /* Check if the line is a SYSV include directive. */
2489 static bool
2490 IsSysVInclude(const char *line)
2491 {
2492 	const char *p;
2493 
2494 	if (!IsInclude(line, true))
2495 		return false;
2496 
2497 	/* Avoid interpreting a dependency line as an include */
2498 	for (p = line; (p = strchr(p, ':')) != NULL;) {
2499 
2500 		/* end of line -> it's a dependency */
2501 		if (*++p == '\0')
2502 			return false;
2503 
2504 		/* '::' operator or ': ' -> it's a dependency */
2505 		if (*p == ':' || ch_isspace(*p))
2506 			return false;
2507 	}
2508 	return true;
2509 }
2510 
2511 /* Push to another file.  The line points to the word "include". */
2512 static void
2513 ParseTraditionalInclude(char *line)
2514 {
2515 	char *cp;		/* current position in file spec */
2516 	bool done = false;
2517 	bool silent = line[0] != 'i';
2518 	char *file = line + (silent ? 8 : 7);
2519 	char *all_files;
2520 
2521 	DEBUG2(PARSE, "%s: %s\n", __func__, file);
2522 
2523 	pp_skip_whitespace(&file);
2524 
2525 	/*
2526 	 * Substitute for any variables in the file name before trying to
2527 	 * find the thing.
2528 	 */
2529 	(void)Var_Subst(file, SCOPE_CMDLINE, VARE_WANTRES, &all_files);
2530 	/* TODO: handle errors */
2531 
2532 	if (*file == '\0') {
2533 		Parse_Error(PARSE_FATAL, "Filename missing from \"include\"");
2534 		goto out;
2535 	}
2536 
2537 	for (file = all_files; !done; file = cp + 1) {
2538 		/* Skip to end of line or next whitespace */
2539 		for (cp = file; *cp != '\0' && !ch_isspace(*cp); cp++)
2540 			continue;
2541 
2542 		if (*cp != '\0')
2543 			*cp = '\0';
2544 		else
2545 			done = true;
2546 
2547 		IncludeFile(file, false, false, silent);
2548 	}
2549 out:
2550 	free(all_files);
2551 }
2552 #endif
2553 
2554 #ifdef GMAKEEXPORT
2555 /* Parse "export <variable>=<value>", and actually export it. */
2556 static void
2557 ParseGmakeExport(char *line)
2558 {
2559 	char *variable = line + 6;
2560 	char *value;
2561 
2562 	DEBUG2(PARSE, "%s: %s\n", __func__, variable);
2563 
2564 	pp_skip_whitespace(&variable);
2565 
2566 	for (value = variable; *value != '\0' && *value != '='; value++)
2567 		continue;
2568 
2569 	if (*value != '=') {
2570 		Parse_Error(PARSE_FATAL,
2571 		    "Variable/Value missing from \"export\"");
2572 		return;
2573 	}
2574 	*value++ = '\0';	/* terminate variable */
2575 
2576 	/*
2577 	 * Expand the value before putting it in the environment.
2578 	 */
2579 	(void)Var_Subst(value, SCOPE_CMDLINE, VARE_WANTRES, &value);
2580 	/* TODO: handle errors */
2581 
2582 	setenv(variable, value, 1);
2583 	free(value);
2584 }
2585 #endif
2586 
2587 /*
2588  * Called when EOF is reached in the current file. If we were reading an
2589  * include file or a .for loop, the includes stack is popped and things set
2590  * up to go back to reading the previous file at the previous location.
2591  *
2592  * Results:
2593  *	true to continue parsing, i.e. it had only reached the end of an
2594  *	included file, false if the main file has been parsed completely.
2595  */
2596 static bool
2597 ParseEOF(void)
2598 {
2599 	char *ptr;
2600 	size_t len;
2601 	IFile *curFile = CurFile();
2602 
2603 	assert(curFile->readMore != NULL);
2604 
2605 	doing_depend = curFile->depending;	/* restore this */
2606 	/* get next input buffer, if any */
2607 	ptr = curFile->readMore(curFile->readMoreArg, &len);
2608 	curFile->buf_ptr = ptr;
2609 	curFile->buf_freeIt = ptr;
2610 	curFile->buf_end = ptr == NULL ? NULL : ptr + len;
2611 	curFile->lineno = curFile->first_lineno;
2612 	if (ptr != NULL)
2613 		return true;	/* Iterate again */
2614 
2615 	/* Ensure the makefile (or loop) didn't have mismatched conditionals */
2616 	Cond_restore_depth(curFile->cond_depth);
2617 
2618 	if (curFile->lf != NULL) {
2619 		loadedfile_destroy(curFile->lf);
2620 		curFile->lf = NULL;
2621 	}
2622 
2623 	/* Dispose of curFile info */
2624 	/* Leak curFile->fname because all the GNodes have pointers to it. */
2625 	free(curFile->buf_freeIt);
2626 	Vector_Pop(&includes);
2627 
2628 	if (includes.len == 0) {
2629 		/* We've run out of input */
2630 		Global_Delete(".PARSEDIR");
2631 		Global_Delete(".PARSEFILE");
2632 		Global_Delete(".INCLUDEDFROMDIR");
2633 		Global_Delete(".INCLUDEDFROMFILE");
2634 		return false;
2635 	}
2636 
2637 	curFile = CurFile();
2638 	DEBUG2(PARSE, "ParseEOF: returning to file %s, line %d\n",
2639 	    curFile->fname, curFile->lineno);
2640 
2641 	ParseSetParseFile(curFile->fname);
2642 	return true;
2643 }
2644 
2645 typedef enum ParseRawLineResult {
2646 	PRLR_LINE,
2647 	PRLR_EOF,
2648 	PRLR_ERROR
2649 } ParseRawLineResult;
2650 
2651 /*
2652  * Parse until the end of a line, taking into account lines that end with
2653  * backslash-newline.  The resulting line goes from out_line to out_line_end;
2654  * the line is not null-terminated.
2655  */
2656 static ParseRawLineResult
2657 ParseRawLine(IFile *curFile, char **out_line, char **out_line_end,
2658 	     char **out_firstBackslash, char **out_firstComment)
2659 {
2660 	char *line = curFile->buf_ptr;
2661 	char *buf_end = curFile->buf_end;
2662 	char *p = line;
2663 	char *line_end = line;
2664 	char *firstBackslash = NULL;
2665 	char *firstComment = NULL;
2666 	ParseRawLineResult res = PRLR_LINE;
2667 
2668 	curFile->lineno++;
2669 
2670 	for (;;) {
2671 		char ch;
2672 
2673 		if (p == buf_end) {
2674 			res = PRLR_EOF;
2675 			break;
2676 		}
2677 
2678 		ch = *p;
2679 		if (ch == '\0' ||
2680 		    (ch == '\\' && p + 1 < buf_end && p[1] == '\0')) {
2681 			Parse_Error(PARSE_FATAL, "Zero byte read from file");
2682 			return PRLR_ERROR;
2683 		}
2684 
2685 		/* Treat next character after '\' as literal. */
2686 		if (ch == '\\') {
2687 			if (firstBackslash == NULL)
2688 				firstBackslash = p;
2689 			if (p[1] == '\n') {
2690 				curFile->lineno++;
2691 				if (p + 2 == buf_end) {
2692 					line_end = p;
2693 					*line_end = '\n';
2694 					p += 2;
2695 					continue;
2696 				}
2697 			}
2698 			p += 2;
2699 			line_end = p;
2700 			assert(p <= buf_end);
2701 			continue;
2702 		}
2703 
2704 		/*
2705 		 * Remember the first '#' for comment stripping, unless
2706 		 * the previous char was '[', as in the modifier ':[#]'.
2707 		 */
2708 		if (ch == '#' && firstComment == NULL &&
2709 		    !(p > line && p[-1] == '['))
2710 			firstComment = line_end;
2711 
2712 		p++;
2713 		if (ch == '\n')
2714 			break;
2715 
2716 		/* We are not interested in trailing whitespace. */
2717 		if (!ch_isspace(ch))
2718 			line_end = p;
2719 	}
2720 
2721 	*out_line = line;
2722 	curFile->buf_ptr = p;
2723 	*out_line_end = line_end;
2724 	*out_firstBackslash = firstBackslash;
2725 	*out_firstComment = firstComment;
2726 	return res;
2727 }
2728 
2729 /*
2730  * Beginning at start, unescape '\#' to '#' and replace backslash-newline
2731  * with a single space.
2732  */
2733 static void
2734 UnescapeBackslash(char *line, char *start)
2735 {
2736 	char *src = start;
2737 	char *dst = start;
2738 	char *spaceStart = line;
2739 
2740 	for (;;) {
2741 		char ch = *src++;
2742 		if (ch != '\\') {
2743 			if (ch == '\0')
2744 				break;
2745 			*dst++ = ch;
2746 			continue;
2747 		}
2748 
2749 		ch = *src++;
2750 		if (ch == '\0') {
2751 			/* Delete '\\' at end of buffer */
2752 			dst--;
2753 			break;
2754 		}
2755 
2756 		/* Delete '\\' from before '#' on non-command lines */
2757 		if (ch == '#' && line[0] != '\t') {
2758 			*dst++ = ch;
2759 			continue;
2760 		}
2761 
2762 		if (ch != '\n') {
2763 			/* Leave '\\' in buffer for later */
2764 			*dst++ = '\\';
2765 			/*
2766 			 * Make sure we don't delete an escaped ' ' from the
2767 			 * line end.
2768 			 */
2769 			spaceStart = dst + 1;
2770 			*dst++ = ch;
2771 			continue;
2772 		}
2773 
2774 		/*
2775 		 * Escaped '\n' -- replace following whitespace with a single
2776 		 * ' '.
2777 		 */
2778 		pp_skip_hspace(&src);
2779 		*dst++ = ' ';
2780 	}
2781 
2782 	/* Delete any trailing spaces - eg from empty continuations */
2783 	while (dst > spaceStart && ch_isspace(dst[-1]))
2784 		dst--;
2785 	*dst = '\0';
2786 }
2787 
2788 typedef enum GetLineMode {
2789 	/*
2790 	 * Return the next line that is neither empty nor a comment.
2791 	 * Backslash line continuations are folded into a single space.
2792 	 * A trailing comment, if any, is discarded.
2793 	 */
2794 	GLM_NONEMPTY,
2795 
2796 	/*
2797 	 * Return the next line, even if it is empty or a comment.
2798 	 * Preserve backslash-newline to keep the line numbers correct.
2799 	 *
2800 	 * Used in .for loops to collect the body of the loop while waiting
2801 	 * for the corresponding .endfor.
2802 	 */
2803 	GLM_FOR_BODY,
2804 
2805 	/*
2806 	 * Return the next line that starts with a dot.
2807 	 * Backslash line continuations are folded into a single space.
2808 	 * A trailing comment, if any, is discarded.
2809 	 *
2810 	 * Used in .if directives to skip over irrelevant branches while
2811 	 * waiting for the corresponding .endif.
2812 	 */
2813 	GLM_DOT
2814 } GetLineMode;
2815 
2816 /* Return the next "interesting" logical line from the current file. */
2817 static char *
2818 ParseGetLine(GetLineMode mode)
2819 {
2820 	IFile *curFile = CurFile();
2821 	char *line;
2822 	char *line_end;
2823 	char *firstBackslash;
2824 	char *firstComment;
2825 
2826 	for (;;) {
2827 		ParseRawLineResult res = ParseRawLine(curFile,
2828 		    &line, &line_end, &firstBackslash, &firstComment);
2829 		if (res == PRLR_ERROR)
2830 			return NULL;
2831 
2832 		if (line_end == line || firstComment == line) {
2833 			if (res == PRLR_EOF)
2834 				return NULL;
2835 			if (mode != GLM_FOR_BODY)
2836 				continue;
2837 		}
2838 
2839 		/* We now have a line of data */
2840 		assert(ch_isspace(*line_end));
2841 		*line_end = '\0';
2842 
2843 		if (mode == GLM_FOR_BODY)
2844 			return line;	/* Don't join the physical lines. */
2845 
2846 		if (mode == GLM_DOT && line[0] != '.')
2847 			continue;
2848 		break;
2849 	}
2850 
2851 	/* Brutally ignore anything after a non-escaped '#' in non-commands. */
2852 	if (firstComment != NULL && line[0] != '\t')
2853 		*firstComment = '\0';
2854 
2855 	/* If we didn't see a '\\' then the in-situ data is fine. */
2856 	if (firstBackslash == NULL)
2857 		return line;
2858 
2859 	/* Remove escapes from '\n' and '#' */
2860 	UnescapeBackslash(line, firstBackslash);
2861 
2862 	return line;
2863 }
2864 
2865 static bool
2866 ParseSkippedBranches(void)
2867 {
2868 	char *line;
2869 
2870 	while ((line = ParseGetLine(GLM_DOT)) != NULL) {
2871 		if (Cond_EvalLine(line) == COND_PARSE)
2872 			break;
2873 		/*
2874 		 * TODO: Check for typos in .elif directives
2875 		 * such as .elsif or .elseif.
2876 		 *
2877 		 * This check will probably duplicate some of
2878 		 * the code in ParseLine.  Most of the code
2879 		 * there cannot apply, only ParseVarassign and
2880 		 * ParseDependencyLine can, and to prevent code
2881 		 * duplication, these would need to be called
2882 		 * with a flag called onlyCheckSyntax.
2883 		 *
2884 		 * See directive-elif.mk for details.
2885 		 */
2886 	}
2887 
2888 	return line != NULL;
2889 }
2890 
2891 static bool
2892 ParseForLoop(const char *line)
2893 {
2894 	int rval;
2895 	int firstLineno;
2896 
2897 	rval = For_Eval(line);
2898 	if (rval == 0)
2899 		return false;	/* Not a .for line */
2900 	if (rval < 0)
2901 		return true;	/* Syntax error - error printed, ignore line */
2902 
2903 	firstLineno = CurFile()->lineno;
2904 
2905 	/* Accumulate loop lines until matching .endfor */
2906 	do {
2907 		line = ParseGetLine(GLM_FOR_BODY);
2908 		if (line == NULL) {
2909 			Parse_Error(PARSE_FATAL,
2910 			    "Unexpected end of file in .for loop");
2911 			break;
2912 		}
2913 	} while (For_Accum(line));
2914 
2915 	For_Run(firstLineno);	/* Stash each iteration as a new 'input file' */
2916 
2917 	return true;		/* Read next line from for-loop buffer */
2918 }
2919 
2920 /*
2921  * Read an entire line from the input file.
2922  *
2923  * Empty lines, .if and .for are completely handled by this function,
2924  * leaving only variable assignments, other directives, dependency lines
2925  * and shell commands to the caller.
2926  *
2927  * Results:
2928  *	A line without its newline and without any trailing whitespace,
2929  *	or NULL.
2930  */
2931 static char *
2932 ParseReadLine(void)
2933 {
2934 	char *line;
2935 
2936 	for (;;) {
2937 		line = ParseGetLine(GLM_NONEMPTY);
2938 		if (line == NULL)
2939 			return NULL;
2940 
2941 		if (line[0] != '.')
2942 			return line;
2943 
2944 		/*
2945 		 * The line might be a conditional. Ask the conditional module
2946 		 * about it and act accordingly
2947 		 */
2948 		switch (Cond_EvalLine(line)) {
2949 		case COND_SKIP:
2950 			if (!ParseSkippedBranches())
2951 				return NULL;
2952 			continue;
2953 		case COND_PARSE:
2954 			continue;
2955 		case COND_INVALID:	/* Not a conditional line */
2956 			if (ParseForLoop(line))
2957 				continue;
2958 			break;
2959 		}
2960 		return line;
2961 	}
2962 }
2963 
2964 static void
2965 FinishDependencyGroup(void)
2966 {
2967 	GNodeListNode *ln;
2968 
2969 	if (targets == NULL)
2970 		return;
2971 
2972 	for (ln = targets->first; ln != NULL; ln = ln->next) {
2973 		GNode *gn = ln->datum;
2974 
2975 		Suff_EndTransform(gn);
2976 
2977 		/*
2978 		 * Mark the target as already having commands if it does, to
2979 		 * keep from having shell commands on multiple dependency
2980 		 * lines.
2981 		 */
2982 		if (!Lst_IsEmpty(&gn->commands))
2983 			gn->type |= OP_HAS_COMMANDS;
2984 	}
2985 
2986 	Lst_Free(targets);
2987 	targets = NULL;
2988 }
2989 
2990 /* Add the command to each target from the current dependency spec. */
2991 static void
2992 ParseLine_ShellCommand(const char *p)
2993 {
2994 	cpp_skip_whitespace(&p);
2995 	if (*p == '\0')
2996 		return;		/* skip empty commands */
2997 
2998 	if (targets == NULL) {
2999 		Parse_Error(PARSE_FATAL,
3000 		    "Unassociated shell command \"%s\"", p);
3001 		return;
3002 	}
3003 
3004 	{
3005 		char *cmd = bmake_strdup(p);
3006 		GNodeListNode *ln;
3007 
3008 		for (ln = targets->first; ln != NULL; ln = ln->next) {
3009 			GNode *gn = ln->datum;
3010 			ParseAddCmd(gn, cmd);
3011 		}
3012 #ifdef CLEANUP
3013 		Lst_Append(&targCmds, cmd);
3014 #endif
3015 	}
3016 }
3017 
3018 /*
3019  * See if the line starts with one of the known directives, and if so, handle
3020  * the directive.
3021  */
3022 static bool
3023 ParseDirective(char *line)
3024 {
3025 	char *cp = line + 1;
3026 	const char *arg;
3027 	Substring dir;
3028 
3029 	pp_skip_whitespace(&cp);
3030 	if (IsInclude(cp, false)) {
3031 		ParseInclude(cp);
3032 		return true;
3033 	}
3034 
3035 	dir.start = cp;
3036 	while (ch_isalpha(*cp) || *cp == '-')
3037 		cp++;
3038 	dir.end = cp;
3039 
3040 	if (*cp != '\0' && !ch_isspace(*cp))
3041 		return false;
3042 
3043 	pp_skip_whitespace(&cp);
3044 	arg = cp;
3045 
3046 	if (Substring_Equals(dir, "undef")) {
3047 		Var_Undef(arg);
3048 		return true;
3049 	} else if (Substring_Equals(dir, "export")) {
3050 		Var_Export(VEM_PLAIN, arg);
3051 		return true;
3052 	} else if (Substring_Equals(dir, "export-env")) {
3053 		Var_Export(VEM_ENV, arg);
3054 		return true;
3055 	} else if (Substring_Equals(dir, "export-literal")) {
3056 		Var_Export(VEM_LITERAL, arg);
3057 		return true;
3058 	} else if (Substring_Equals(dir, "unexport")) {
3059 		Var_UnExport(false, arg);
3060 		return true;
3061 	} else if (Substring_Equals(dir, "unexport-env")) {
3062 		Var_UnExport(true, arg);
3063 		return true;
3064 	} else if (Substring_Equals(dir, "info")) {
3065 		ParseMessage(PARSE_INFO, "info", arg);
3066 		return true;
3067 	} else if (Substring_Equals(dir, "warning")) {
3068 		ParseMessage(PARSE_WARNING, "warning", arg);
3069 		return true;
3070 	} else if (Substring_Equals(dir, "error")) {
3071 		ParseMessage(PARSE_FATAL, "error", arg);
3072 		return true;
3073 	}
3074 	return false;
3075 }
3076 
3077 static bool
3078 ParseVarassign(const char *line)
3079 {
3080 	VarAssign var;
3081 
3082 	if (!Parse_IsVar(line, &var))
3083 		return false;
3084 
3085 	FinishDependencyGroup();
3086 	Parse_Var(&var, SCOPE_GLOBAL);
3087 	return true;
3088 }
3089 
3090 static char *
3091 FindSemicolon(char *p)
3092 {
3093 	int level = 0;
3094 
3095 	for (; *p != '\0'; p++) {
3096 		if (*p == '\\' && p[1] != '\0') {
3097 			p++;
3098 			continue;
3099 		}
3100 
3101 		if (*p == '$' && (p[1] == '(' || p[1] == '{'))
3102 			level++;
3103 		else if (level > 0 && (*p == ')' || *p == '}'))
3104 			level--;
3105 		else if (level == 0 && *p == ';')
3106 			break;
3107 	}
3108 	return p;
3109 }
3110 
3111 /*
3112  * dependency	-> target... op [source...] [';' command]
3113  * op		-> ':' | '::' | '!'
3114  */
3115 static void
3116 ParseDependencyLine(char *line)
3117 {
3118 	VarEvalMode emode;
3119 	char *expanded_line;
3120 	const char *shellcmd = NULL;
3121 
3122 	/*
3123 	 * For some reason - probably to make the parser impossible -
3124 	 * a ';' can be used to separate commands from dependencies.
3125 	 * Attempt to avoid ';' inside substitution patterns.
3126 	 */
3127 	{
3128 		char *semicolon = FindSemicolon(line);
3129 		if (*semicolon != '\0') {
3130 			/* Terminate the dependency list at the ';' */
3131 			*semicolon = '\0';
3132 			shellcmd = semicolon + 1;
3133 		}
3134 	}
3135 
3136 	/*
3137 	 * We now know it's a dependency line so it needs to have all
3138 	 * variables expanded before being parsed.
3139 	 *
3140 	 * XXX: Ideally the dependency line would first be split into
3141 	 * its left-hand side, dependency operator and right-hand side,
3142 	 * and then each side would be expanded on its own.  This would
3143 	 * allow for the left-hand side to allow only defined variables
3144 	 * and to allow variables on the right-hand side to be undefined
3145 	 * as well.
3146 	 *
3147 	 * Parsing the line first would also prevent that targets
3148 	 * generated from variable expressions are interpreted as the
3149 	 * dependency operator, such as in "target${:U\:} middle: source",
3150 	 * in which the middle is interpreted as a source, not a target.
3151 	 */
3152 
3153 	/* In lint mode, allow undefined variables to appear in
3154 	 * dependency lines.
3155 	 *
3156 	 * Ideally, only the right-hand side would allow undefined
3157 	 * variables since it is common to have optional dependencies.
3158 	 * Having undefined variables on the left-hand side is more
3159 	 * unusual though.  Since both sides are expanded in a single
3160 	 * pass, there is not much choice what to do here.
3161 	 *
3162 	 * In normal mode, it does not matter whether undefined
3163 	 * variables are allowed or not since as of 2020-09-14,
3164 	 * Var_Parse does not print any parse errors in such a case.
3165 	 * It simply returns the special empty string var_Error,
3166 	 * which cannot be detected in the result of Var_Subst. */
3167 	emode = opts.strict ? VARE_WANTRES : VARE_UNDEFERR;
3168 	(void)Var_Subst(line, SCOPE_CMDLINE, emode, &expanded_line);
3169 	/* TODO: handle errors */
3170 
3171 	/* Need a fresh list for the target nodes */
3172 	if (targets != NULL)
3173 		Lst_Free(targets);
3174 	targets = Lst_New();
3175 
3176 	ParseDependency(expanded_line);
3177 	free(expanded_line);
3178 
3179 	if (shellcmd != NULL)
3180 		ParseLine_ShellCommand(shellcmd);
3181 }
3182 
3183 static void
3184 ParseLine(char *line)
3185 {
3186 	/*
3187 	 * Lines that begin with '.' can be pretty much anything:
3188 	 *	- directives like '.include' or '.if',
3189 	 *	- suffix rules like '.c.o:',
3190 	 *	- dependencies for filenames that start with '.',
3191 	 *	- variable assignments like '.tmp=value'.
3192 	 */
3193 	if (line[0] == '.' && ParseDirective(line))
3194 		return;
3195 
3196 	if (line[0] == '\t') {
3197 		ParseLine_ShellCommand(line + 1);
3198 		return;
3199 	}
3200 
3201 #ifdef SYSVINCLUDE
3202 	if (IsSysVInclude(line)) {
3203 		/*
3204 		 * It's an S3/S5-style "include".
3205 		 */
3206 		ParseTraditionalInclude(line);
3207 		return;
3208 	}
3209 #endif
3210 
3211 #ifdef GMAKEEXPORT
3212 	if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
3213 	    strchr(line, ':') == NULL) {
3214 		/*
3215 		 * It's a Gmake "export".
3216 		 */
3217 		ParseGmakeExport(line);
3218 		return;
3219 	}
3220 #endif
3221 
3222 	if (ParseVarassign(line))
3223 		return;
3224 
3225 	FinishDependencyGroup();
3226 
3227 	ParseDependencyLine(line);
3228 }
3229 
3230 /*
3231  * Parse a top-level makefile, incorporating its content into the global
3232  * dependency graph.
3233  *
3234  * Input:
3235  *	name		The name of the file being read
3236  *	fd		The open file to parse; will be closed at the end
3237  */
3238 void
3239 Parse_File(const char *name, int fd)
3240 {
3241 	char *line;		/* the line we're working on */
3242 	struct loadedfile *lf;
3243 
3244 	lf = loadfile(name, fd);
3245 
3246 	assert(targets == NULL);
3247 
3248 	if (name == NULL)
3249 		name = "(stdin)";
3250 
3251 	Parse_PushInput(name, 0, -1, loadedfile_readMore, lf);
3252 	CurFile()->lf = lf;
3253 
3254 	do {
3255 		while ((line = ParseReadLine()) != NULL) {
3256 			DEBUG2(PARSE, "ParseReadLine (%d): '%s'\n",
3257 			    CurFile()->lineno, line);
3258 			ParseLine(line);
3259 		}
3260 		/* Reached EOF, but it may be just EOF of an include file. */
3261 	} while (ParseEOF());
3262 
3263 	FinishDependencyGroup();
3264 
3265 	if (parseErrors != 0) {
3266 		(void)fflush(stdout);
3267 		(void)fprintf(stderr,
3268 		    "%s: Fatal errors encountered -- cannot continue",
3269 		    progname);
3270 		PrintOnError(NULL, NULL);
3271 		exit(1);
3272 	}
3273 }
3274 
3275 /* Initialize the parsing module. */
3276 void
3277 Parse_Init(void)
3278 {
3279 	mainNode = NULL;
3280 	parseIncPath = SearchPath_New();
3281 	sysIncPath = SearchPath_New();
3282 	defSysIncPath = SearchPath_New();
3283 	Vector_Init(&includes, sizeof(IFile));
3284 }
3285 
3286 /* Clean up the parsing module. */
3287 void
3288 Parse_End(void)
3289 {
3290 #ifdef CLEANUP
3291 	Lst_DoneCall(&targCmds, free);
3292 	assert(targets == NULL);
3293 	SearchPath_Free(defSysIncPath);
3294 	SearchPath_Free(sysIncPath);
3295 	SearchPath_Free(parseIncPath);
3296 	assert(includes.len == 0);
3297 	Vector_Done(&includes);
3298 #endif
3299 }
3300 
3301 
3302 /*
3303  * Return a list containing the single main target to create.
3304  * If no such target exists, we Punt with an obnoxious error message.
3305  */
3306 void
3307 Parse_MainName(GNodeList *mainList)
3308 {
3309 	if (mainNode == NULL)
3310 		Punt("no target to make.");
3311 
3312 	Lst_Append(mainList, mainNode);
3313 	if (mainNode->type & OP_DOUBLEDEP)
3314 		Lst_AppendAll(mainList, &mainNode->cohorts);
3315 
3316 	Global_Append(".TARGETS", mainNode->name);
3317 }
3318 
3319 int
3320 Parse_NumErrors(void)
3321 {
3322 	return parseErrors;
3323 }
3324