xref: /freebsd/contrib/bmake/parse.c (revision 36d6566e5985030fd2f1100bd9c1387bbe0bd290)
1 /*	$NetBSD: parse.c,v 1.420 2020/11/01 00:24:57 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 Parse_include_file though.
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 1.420 2020/11/01 00:24:57 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 */
136     Boolean 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     Boolean depending;		/* state of doing_depend on EOF */
141 
142     /* The buffer from which the file's content is read. */
143     char *buf_freeIt;
144     char *buf_ptr;		/* next char to be read */
145     char *buf_end;
146 
147     char *(*nextbuf)(void *, size_t *); /* Function to get more data */
148     void *nextbuf_arg;		/* Opaque arg for nextbuf() */
149     struct loadedfile *lf;	/* loadedfile object, if any */
150 } IFile;
151 
152 /*
153  * Tokens for target attributes
154  */
155 typedef enum ParseSpecial {
156     SP_ATTRIBUTE,	/* Generic attribute */
157     SP_BEGIN,		/* .BEGIN */
158     SP_DEFAULT,		/* .DEFAULT */
159     SP_DELETE_ON_ERROR,	/* .DELETE_ON_ERROR */
160     SP_END,		/* .END */
161     SP_ERROR,		/* .ERROR */
162     SP_IGNORE,		/* .IGNORE */
163     SP_INCLUDES,	/* .INCLUDES; not mentioned in the manual page */
164     SP_INTERRUPT,	/* .INTERRUPT */
165     SP_LIBS,		/* .LIBS; not mentioned in the manual page */
166     SP_MAIN,		/* .MAIN and we don't have anything user-specified to
167 			 * make */
168     SP_META,		/* .META */
169     SP_MFLAGS,		/* .MFLAGS or .MAKEFLAGS */
170     SP_NOMETA,		/* .NOMETA */
171     SP_NOMETA_CMP,	/* .NOMETA_CMP */
172     SP_NOPATH,		/* .NOPATH */
173     SP_NOT,		/* Not special */
174     SP_NOTPARALLEL,	/* .NOTPARALLEL or .NO_PARALLEL */
175     SP_NULL,		/* .NULL; not mentioned in the manual page */
176     SP_OBJDIR,		/* .OBJDIR */
177     SP_ORDER,		/* .ORDER */
178     SP_PARALLEL,	/* .PARALLEL; not mentioned in the manual page */
179     SP_PATH,		/* .PATH or .PATH.suffix */
180     SP_PHONY,		/* .PHONY */
181 #ifdef POSIX
182     SP_POSIX,		/* .POSIX; not mentioned in the manual page */
183 #endif
184     SP_PRECIOUS,	/* .PRECIOUS */
185     SP_SHELL,		/* .SHELL */
186     SP_SILENT,		/* .SILENT */
187     SP_SINGLESHELL,	/* .SINGLESHELL; not mentioned in the manual page */
188     SP_STALE,		/* .STALE */
189     SP_SUFFIXES,	/* .SUFFIXES */
190     SP_WAIT		/* .WAIT */
191 } ParseSpecial;
192 
193 typedef List SearchPathList;
194 typedef ListNode SearchPathListNode;
195 
196 /* result data */
197 
198 /*
199  * The main target to create. This is the first target on the first
200  * dependency line in the first makefile.
201  */
202 static GNode *mainNode;
203 
204 /* eval state */
205 
206 /* During parsing, the targets from the left-hand side of the currently
207  * active dependency line, or NULL if the current line does not belong to a
208  * dependency line, for example because it is a variable assignment.
209  *
210  * See unit-tests/deptgt.mk, keyword "parse.c:targets". */
211 static GNodeList *targets;
212 
213 #ifdef CLEANUP
214 /* All shell commands for all targets, in no particular order and possibly
215  * with duplicates.  Kept in a separate list since the commands from .USE or
216  * .USEBEFORE nodes are shared with other GNodes, thereby giving up the
217  * easily understandable ownership over the allocated strings. */
218 static StringList *targCmds;
219 #endif
220 
221 /*
222  * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
223  * seen, then set to each successive source on the line.
224  */
225 static GNode *order_pred;
226 
227 /* parser state */
228 
229 /* number of fatal errors */
230 static int fatals = 0;
231 
232 /*
233  * Variables for doing includes
234  */
235 
236 /* The include chain of makefiles.  At the bottom is the top-level makefile
237  * from the command line, and on top of that, there are the included files or
238  * .for loops, up to and including the current file.
239  *
240  * This data could be used to print stack traces on parse errors.  As of
241  * 2020-09-14, this is not done though.  It seems quite simple to print the
242  * tuples (fname:lineno:fromForLoop), from top to bottom.  This simple idea is
243  * made complicated by the fact that the .for loops also use this stack for
244  * storing information.
245  *
246  * The lineno fields of the IFiles with fromForLoop == TRUE look confusing,
247  * which is demonstrated by the test 'include-main.mk'.  They seem sorted
248  * backwards since they tell the number of completely parsed lines, which for
249  * a .for loop is right after the terminating .endfor.  To compensate for this
250  * confusion, there is another field first_lineno pointing at the start of the
251  * .for loop, 1-based for human consumption.
252  *
253  * To make the stack trace intuitive, the entry below the first .for loop must
254  * be ignored completely since neither its lineno nor its first_lineno is
255  * useful.  Instead, the topmost of each chain of .for loop needs to be
256  * printed twice, once with its first_lineno and once with its lineno.
257  *
258  * As of 2020-10-28, using the above rules, the stack trace for the .info line
259  * in include-subsub.mk would be:
260  *
261  *	includes[5]:	include-subsub.mk:4
262  *			(lineno, from an .include)
263  *	includes[4]:	include-sub.mk:32
264  *			(lineno, from a .for loop below an .include)
265  *	includes[4]:	include-sub.mk:31
266  *			(first_lineno, from a .for loop, lineno == 32)
267  *	includes[3]:	include-sub.mk:30
268  *			(first_lineno, from a .for loop, lineno == 33)
269  *	includes[2]:	include-sub.mk:29
270  *			(first_lineno, from a .for loop, lineno == 34)
271  *	includes[1]:	include-sub.mk:35
272  *			(not printed since it is below a .for loop)
273  *	includes[0]:	include-main.mk:27
274  */
275 static Vector /* of IFile */ includes;
276 
277 static IFile *
278 GetInclude(size_t i)
279 {
280     return Vector_Get(&includes, i);
281 }
282 
283 /* The file that is currently being read. */
284 static IFile *
285 CurFile(void)
286 {
287     return GetInclude(includes.len - 1);
288 }
289 
290 /* include paths */
291 SearchPath *parseIncPath;	/* dirs for "..." includes */
292 SearchPath *sysIncPath;		/* dirs for <...> includes */
293 SearchPath *defSysIncPath;	/* default for sysIncPath */
294 
295 /* parser tables */
296 
297 /*
298  * The parseKeywords table is searched using binary search when deciding
299  * if a target or source is special. The 'spec' field is the ParseSpecial
300  * type of the keyword (SP_NOT if the keyword isn't special as a target) while
301  * the 'op' field is the operator to apply to the list of targets if the
302  * keyword is used as a source ("0" if the keyword isn't special as a source)
303  */
304 static const struct {
305     const char   *name;		/* Name of keyword */
306     ParseSpecial  spec;		/* Type when used as a target */
307     GNodeType	  op;		/* Operator when used as a source */
308 } parseKeywords[] = {
309     { ".BEGIN",		SP_BEGIN,	0 },
310     { ".DEFAULT",	SP_DEFAULT,	0 },
311     { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, 0 },
312     { ".END",		SP_END,		0 },
313     { ".ERROR",		SP_ERROR,	0 },
314     { ".EXEC",		SP_ATTRIBUTE,	OP_EXEC },
315     { ".IGNORE",	SP_IGNORE,	OP_IGNORE },
316     { ".INCLUDES",	SP_INCLUDES,	0 },
317     { ".INTERRUPT",	SP_INTERRUPT,	0 },
318     { ".INVISIBLE",	SP_ATTRIBUTE,	OP_INVISIBLE },
319     { ".JOIN",		SP_ATTRIBUTE,	OP_JOIN },
320     { ".LIBS",		SP_LIBS,	0 },
321     { ".MADE",		SP_ATTRIBUTE,	OP_MADE },
322     { ".MAIN",		SP_MAIN,	0 },
323     { ".MAKE",		SP_ATTRIBUTE,	OP_MAKE },
324     { ".MAKEFLAGS",	SP_MFLAGS,	0 },
325     { ".META",		SP_META,	OP_META },
326     { ".MFLAGS",	SP_MFLAGS,	0 },
327     { ".NOMETA",	SP_NOMETA,	OP_NOMETA },
328     { ".NOMETA_CMP",	SP_NOMETA_CMP,	OP_NOMETA_CMP },
329     { ".NOPATH",	SP_NOPATH,	OP_NOPATH },
330     { ".NOTMAIN",	SP_ATTRIBUTE,	OP_NOTMAIN },
331     { ".NOTPARALLEL",	SP_NOTPARALLEL,	0 },
332     { ".NO_PARALLEL",	SP_NOTPARALLEL,	0 },
333     { ".NULL",		SP_NULL,	0 },
334     { ".OBJDIR",	SP_OBJDIR,	0 },
335     { ".OPTIONAL",	SP_ATTRIBUTE,	OP_OPTIONAL },
336     { ".ORDER",		SP_ORDER,	0 },
337     { ".PARALLEL",	SP_PARALLEL,	0 },
338     { ".PATH",		SP_PATH,	0 },
339     { ".PHONY",		SP_PHONY,	OP_PHONY },
340 #ifdef POSIX
341     { ".POSIX",		SP_POSIX,	0 },
342 #endif
343     { ".PRECIOUS",	SP_PRECIOUS,	OP_PRECIOUS },
344     { ".RECURSIVE",	SP_ATTRIBUTE,	OP_MAKE },
345     { ".SHELL",		SP_SHELL,	0 },
346     { ".SILENT",	SP_SILENT,	OP_SILENT },
347     { ".SINGLESHELL",	SP_SINGLESHELL,	0 },
348     { ".STALE",		SP_STALE,	0 },
349     { ".SUFFIXES",	SP_SUFFIXES,	0 },
350     { ".USE",		SP_ATTRIBUTE,	OP_USE },
351     { ".USEBEFORE",	SP_ATTRIBUTE,	OP_USEBEFORE },
352     { ".WAIT",		SP_WAIT,	0 },
353 };
354 
355 /* file loader */
356 
357 struct loadedfile {
358 	const char *path;		/* name, for error reports */
359 	char *buf;			/* contents buffer */
360 	size_t len;			/* length of contents */
361 	size_t maplen;			/* length of mmap area, or 0 */
362 	Boolean used;			/* XXX: have we used the data yet */
363 };
364 
365 static struct loadedfile *
366 loadedfile_create(const char *path)
367 {
368 	struct loadedfile *lf;
369 
370 	lf = bmake_malloc(sizeof(*lf));
371 	lf->path = path == NULL ? "(stdin)" : path;
372 	lf->buf = NULL;
373 	lf->len = 0;
374 	lf->maplen = 0;
375 	lf->used = FALSE;
376 	return lf;
377 }
378 
379 static void
380 loadedfile_destroy(struct loadedfile *lf)
381 {
382 	if (lf->buf != NULL) {
383 		if (lf->maplen > 0) {
384 #ifdef HAVE_MMAP
385 			munmap(lf->buf, lf->maplen);
386 #endif
387 		} else {
388 			free(lf->buf);
389 		}
390 	}
391 	free(lf);
392 }
393 
394 /*
395  * nextbuf() operation for loadedfile, as needed by the weird and twisted
396  * logic below. Once that's cleaned up, we can get rid of lf->used...
397  */
398 static char *
399 loadedfile_nextbuf(void *x, size_t *len)
400 {
401 	struct loadedfile *lf = x;
402 
403 	if (lf->used) {
404 		return NULL;
405 	}
406 	lf->used = TRUE;
407 	*len = lf->len;
408 	return lf->buf;
409 }
410 
411 /*
412  * Try to get the size of a file.
413  */
414 static Boolean
415 load_getsize(int fd, size_t *ret)
416 {
417 	struct stat st;
418 
419 	if (fstat(fd, &st) < 0) {
420 		return FALSE;
421 	}
422 
423 	if (!S_ISREG(st.st_mode)) {
424 		return FALSE;
425 	}
426 
427 	/*
428 	 * st_size is an off_t, which is 64 bits signed; *ret is
429 	 * size_t, which might be 32 bits unsigned or 64 bits
430 	 * unsigned. Rather than being elaborate, just punt on
431 	 * files that are more than 2^31 bytes. We should never
432 	 * see a makefile that size in practice...
433 	 *
434 	 * While we're at it reject negative sizes too, just in case.
435 	 */
436 	if (st.st_size < 0 || st.st_size > 0x7fffffff) {
437 		return FALSE;
438 	}
439 
440 	*ret = (size_t)st.st_size;
441 	return TRUE;
442 }
443 
444 #ifdef HAVE_MMAP
445 static Boolean
446 loadedfile_mmap(struct loadedfile *lf, int fd)
447 {
448 	static unsigned long pagesize = 0;
449 
450 	if (load_getsize(fd, &lf->len)) {
451 
452 		/* found a size, try mmap */
453 #ifdef _SC_PAGESIZE
454 		if (pagesize == 0)
455 			pagesize = (unsigned long)sysconf(_SC_PAGESIZE);
456 #endif
457 		if (pagesize == 0 || pagesize == (unsigned long)-1) {
458 			pagesize = 0x1000;
459 		}
460 		/* round size up to a page */
461 		lf->maplen = pagesize * ((lf->len + pagesize - 1) / pagesize);
462 
463 		/*
464 		 * XXX hack for dealing with empty files; remove when
465 		 * we're no longer limited by interfacing to the old
466 		 * logic elsewhere in this file.
467 		 */
468 		if (lf->maplen == 0) {
469 			lf->maplen = pagesize;
470 		}
471 
472 		/*
473 		 * FUTURE: remove PROT_WRITE when the parser no longer
474 		 * needs to scribble on the input.
475 		 */
476 		lf->buf = mmap(NULL, lf->maplen, PROT_READ|PROT_WRITE,
477 			       MAP_FILE|MAP_COPY, fd, 0);
478 		if (lf->buf != MAP_FAILED) {
479 			/* succeeded */
480 			if (lf->len == lf->maplen && lf->buf[lf->len - 1] != '\n') {
481 				char *b = bmake_malloc(lf->len + 1);
482 				b[lf->len] = '\n';
483 				memcpy(b, lf->buf, lf->len++);
484 				munmap(lf->buf, lf->maplen);
485 				lf->maplen = 0;
486 				lf->buf = b;
487 			}
488 			return TRUE;
489 		}
490 	}
491 	return FALSE;
492 }
493 #endif
494 
495 /*
496  * Read in a file.
497  *
498  * Until the path search logic can be moved under here instead of
499  * being in the caller in another source file, we need to have the fd
500  * passed in already open. Bleh.
501  *
502  * If the path is NULL use stdin and (to insure against fd leaks)
503  * assert that the caller passed in -1.
504  */
505 static struct loadedfile *
506 loadfile(const char *path, int fd)
507 {
508 	struct loadedfile *lf;
509 	ssize_t result;
510 	size_t bufpos;
511 
512 	lf = loadedfile_create(path);
513 
514 	if (path == NULL) {
515 		assert(fd == -1);
516 		fd = STDIN_FILENO;
517 	} else {
518 #if 0 /* notyet */
519 		fd = open(path, O_RDONLY);
520 		if (fd < 0) {
521 			...
522 			Error("%s: %s", path, strerror(errno));
523 			exit(1);
524 		}
525 #endif
526 	}
527 
528 #ifdef HAVE_MMAP
529 	if (loadedfile_mmap(lf, fd))
530 		goto done;
531 #endif
532 
533 	/* cannot mmap; load the traditional way */
534 
535 	lf->maplen = 0;
536 	lf->len = 1024;
537 	lf->buf = bmake_malloc(lf->len);
538 
539 	bufpos = 0;
540 	while (1) {
541 		assert(bufpos <= lf->len);
542 		if (bufpos == lf->len) {
543 			if (lf->len > SIZE_MAX/2) {
544 				errno = EFBIG;
545 				Error("%s: file too large", path);
546 				exit(1);
547 			}
548 			lf->len *= 2;
549 			lf->buf = bmake_realloc(lf->buf, lf->len);
550 		}
551 		assert(bufpos < lf->len);
552 		result = read(fd, lf->buf + bufpos, lf->len - bufpos);
553 		if (result < 0) {
554 			Error("%s: read error: %s", path, strerror(errno));
555 			exit(1);
556 		}
557 		if (result == 0) {
558 			break;
559 		}
560 		bufpos += (size_t)result;
561 	}
562 	assert(bufpos <= lf->len);
563 	lf->len = bufpos;
564 
565 	/* truncate malloc region to actual length (maybe not useful) */
566 	if (lf->len > 0) {
567 		/* as for mmap case, ensure trailing \n */
568 		if (lf->buf[lf->len - 1] != '\n')
569 			lf->len++;
570 		lf->buf = bmake_realloc(lf->buf, lf->len);
571 		lf->buf[lf->len - 1] = '\n';
572 	}
573 
574 #ifdef HAVE_MMAP
575 done:
576 #endif
577 	if (path != NULL) {
578 		close(fd);
579 	}
580 	return lf;
581 }
582 
583 /* old code */
584 
585 /* Check if the current character is escaped on the current line. */
586 static Boolean
587 ParseIsEscaped(const char *line, const char *c)
588 {
589     Boolean active = FALSE;
590     for (;;) {
591 	if (line == c)
592 	    return active;
593 	if (*--c != '\\')
594 	    return active;
595 	active = !active;
596     }
597 }
598 
599 /* Add the filename and lineno to the GNode so that we remember where it
600  * was first defined. */
601 static void
602 ParseMark(GNode *gn)
603 {
604     IFile *curFile = CurFile();
605     gn->fname = curFile->fname;
606     gn->lineno = curFile->lineno;
607 }
608 
609 /* Look in the table of keywords for one matching the given string.
610  * Return the index of the keyword, or -1 if it isn't there. */
611 static int
612 ParseFindKeyword(const char *str)
613 {
614     int start, end, cur;
615     int diff;
616 
617     start = 0;
618     end = sizeof parseKeywords / sizeof parseKeywords[0] - 1;
619 
620     do {
621 	cur = start + (end - start) / 2;
622 	diff = strcmp(str, parseKeywords[cur].name);
623 
624 	if (diff == 0) {
625 	    return cur;
626 	} else if (diff < 0) {
627 	    end = cur - 1;
628 	} else {
629 	    start = cur + 1;
630 	}
631     } while (start <= end);
632     return -1;
633 }
634 
635 static void
636 PrintLocation(FILE *f, const char *filename, size_t lineno)
637 {
638 	char dirbuf[MAXPATHLEN+1];
639 	const char *dir, *base;
640 	void *dir_freeIt, *base_freeIt;
641 
642 	if (*filename == '/' || strcmp(filename, "(stdin)") == 0) {
643 		(void)fprintf(f, "\"%s\" line %zu: ", filename, lineno);
644 		return;
645 	}
646 
647 	/* Find out which makefile is the culprit.
648 	 * We try ${.PARSEDIR} and apply realpath(3) if not absolute. */
649 
650 	dir = Var_Value(".PARSEDIR", VAR_GLOBAL, &dir_freeIt);
651 	if (dir == NULL)
652 		dir = ".";
653 	if (*dir != '/')
654 		dir = realpath(dir, dirbuf);
655 
656 	base = Var_Value(".PARSEFILE", VAR_GLOBAL, &base_freeIt);
657 	if (base == NULL) {
658 		const char *slash = strrchr(filename, '/');
659 		base = slash != NULL ? slash + 1 : filename;
660 	}
661 
662 	(void)fprintf(f, "\"%s/%s\" line %zu: ", dir, base, lineno);
663 	bmake_free(base_freeIt);
664 	bmake_free(dir_freeIt);
665 }
666 
667 /* Print a parse error message, including location information.
668  *
669  * Increment "fatals" if the level is PARSE_FATAL, and continue parsing
670  * until the end of the current top-level makefile, then exit (see
671  * Parse_File). */
672 static void
673 ParseVErrorInternal(FILE *f, const char *cfname, size_t clineno,
674 		    ParseErrorLevel type, const char *fmt, va_list ap)
675 {
676 	static Boolean fatal_warning_error_printed = FALSE;
677 
678 	(void)fprintf(f, "%s: ", progname);
679 
680 	if (cfname != NULL)
681 		PrintLocation(f, cfname, clineno);
682 	if (type == PARSE_WARNING)
683 		(void)fprintf(f, "warning: ");
684 	(void)vfprintf(f, fmt, ap);
685 	(void)fprintf(f, "\n");
686 	(void)fflush(f);
687 
688 	if (type == PARSE_INFO)
689 		return;
690 	if (type == PARSE_FATAL || opts.parseWarnFatal)
691 		fatals++;
692 	if (opts.parseWarnFatal && !fatal_warning_error_printed) {
693 		Error("parsing warnings being treated as errors");
694 		fatal_warning_error_printed = TRUE;
695 	}
696 }
697 
698 static void
699 ParseErrorInternal(const char *cfname, size_t clineno, ParseErrorLevel type,
700 		   const char *fmt, ...)
701 {
702 	va_list ap;
703 
704 	va_start(ap, fmt);
705 	(void)fflush(stdout);
706 	ParseVErrorInternal(stderr, cfname, clineno, type, fmt, ap);
707 	va_end(ap);
708 
709 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
710 		va_start(ap, fmt);
711 		ParseVErrorInternal(opts.debug_file, cfname, clineno, type,
712 				    fmt, ap);
713 		va_end(ap);
714 	}
715 }
716 
717 /* External interface to ParseErrorInternal; uses the default filename and
718  * line number.
719  *
720  * Fmt is given without a trailing newline. */
721 void
722 Parse_Error(ParseErrorLevel type, const char *fmt, ...)
723 {
724 	va_list ap;
725 	const char *fname;
726 	size_t lineno;
727 
728 	if (includes.len == 0) {
729 		fname = NULL;
730 		lineno = 0;
731 	} else {
732 		IFile *curFile = CurFile();
733 		fname = curFile->fname;
734 		lineno = (size_t)curFile->lineno;
735 	}
736 
737 	va_start(ap, fmt);
738 	(void)fflush(stdout);
739 	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
740 	va_end(ap);
741 
742 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
743 		va_start(ap, fmt);
744 		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
745 				    fmt, ap);
746 		va_end(ap);
747 	}
748 }
749 
750 
751 /* Parse a .info .warning or .error directive.
752  *
753  * The input is the line minus the ".".  We substitute variables, print the
754  * message and exit(1) (for .error) or just print a warning if the directive
755  * is malformed.
756  */
757 static Boolean
758 ParseMessage(const char *directive)
759 {
760     const char *p = directive;
761     int mtype = *p == 'i' ? PARSE_INFO :
762 		*p == 'w' ? PARSE_WARNING : PARSE_FATAL;
763     char *arg;
764 
765     while (ch_isalpha(*p))
766 	p++;
767     if (!ch_isspace(*p))
768 	return FALSE;		/* missing argument */
769 
770     cpp_skip_whitespace(&p);
771     (void)Var_Subst(p, VAR_CMDLINE, VARE_WANTRES, &arg);
772     /* TODO: handle errors */
773 
774     Parse_Error(mtype, "%s", arg);
775     free(arg);
776 
777     if (mtype == PARSE_FATAL) {
778 	PrintOnError(NULL, NULL);
779 	exit(1);
780     }
781     return TRUE;
782 }
783 
784 /* Add the child to the parent's children.
785  *
786  * Additionally, add the parent to the child's parents, but only if the
787  * target is not special.  An example for such a special target is .END,
788  * which does not need to be informed once the child target has been made. */
789 static void
790 LinkSource(GNode *pgn, GNode *cgn, Boolean isSpecial)
791 {
792     if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(pgn->cohorts))
793 	pgn = pgn->cohorts->last->datum;
794 
795     Lst_Append(pgn->children, cgn);
796     pgn->unmade++;
797 
798     /* Special targets like .END don't need any children. */
799     if (!isSpecial)
800 	Lst_Append(cgn->parents, pgn);
801 
802     if (DEBUG(PARSE)) {
803 	debug_printf("# %s: added child %s - %s\n",
804 		     __func__, pgn->name, cgn->name);
805 	Targ_PrintNode(pgn, 0);
806 	Targ_PrintNode(cgn, 0);
807     }
808 }
809 
810 /* Add the node to each target from the current dependency group. */
811 static void
812 LinkToTargets(GNode *gn, Boolean isSpecial)
813 {
814     GNodeListNode *ln;
815     for (ln = targets->first; ln != NULL; ln = ln->next)
816 	LinkSource(ln->datum, gn, isSpecial);
817 }
818 
819 static Boolean
820 TryApplyDependencyOperator(GNode *gn, GNodeType op)
821 {
822     /*
823      * If the node occurred on the left-hand side of a dependency and the
824      * operator also defines a dependency, they must match.
825      */
826     if ((op & OP_OPMASK) && (gn->type & OP_OPMASK) &&
827 	((op & OP_OPMASK) != (gn->type & OP_OPMASK)))
828     {
829 	Parse_Error(PARSE_FATAL, "Inconsistent operator for %s", gn->name);
830 	return FALSE;
831     }
832 
833     if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
834 	/*
835 	 * If the node was the object of a :: operator, we need to create a
836 	 * new instance of it for the children and commands on this dependency
837 	 * line. The new instance is placed on the 'cohorts' list of the
838 	 * initial one (note the initial one is not on its own cohorts list)
839 	 * and the new instance is linked to all parents of the initial
840 	 * instance.
841 	 */
842 	GNode *cohort;
843 
844 	/*
845 	 * Propagate copied bits to the initial node.  They'll be propagated
846 	 * back to the rest of the cohorts later.
847 	 */
848 	gn->type |= op & ~OP_OPMASK;
849 
850 	cohort = Targ_NewInternalNode(gn->name);
851 	if (doing_depend)
852 	    ParseMark(cohort);
853 	/*
854 	 * Make the cohort invisible as well to avoid duplicating it into
855 	 * other variables. True, parents of this target won't tend to do
856 	 * anything with their local variables, but better safe than
857 	 * sorry. (I think this is pointless now, since the relevant list
858 	 * traversals will no longer see this node anyway. -mycroft)
859 	 */
860 	cohort->type = op | OP_INVISIBLE;
861 	Lst_Append(gn->cohorts, cohort);
862 	cohort->centurion = gn;
863 	gn->unmade_cohorts++;
864 	snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
865 		 (unsigned int)gn->unmade_cohorts % 1000000);
866     } else {
867 	/*
868 	 * We don't want to nuke any previous flags (whatever they were) so we
869 	 * just OR the new operator into the old
870 	 */
871 	gn->type |= op;
872     }
873 
874     return TRUE;
875 }
876 
877 static void
878 ApplyDependencyOperator(GNodeType op)
879 {
880     GNodeListNode *ln;
881     for (ln = targets->first; ln != NULL; ln = ln->next)
882 	if (!TryApplyDependencyOperator(ln->datum, op))
883 	    break;
884 }
885 
886 static Boolean
887 ParseDoSrcKeyword(const char *src, ParseSpecial specType)
888 {
889     static int wait_number = 0;
890     char wait_src[16];
891     GNode *gn;
892 
893     if (*src == '.' && ch_isupper(src[1])) {
894 	int keywd = ParseFindKeyword(src);
895 	if (keywd != -1) {
896 	    int op = parseKeywords[keywd].op;
897 	    if (op != 0) {
898 		ApplyDependencyOperator(op);
899 		return TRUE;
900 	    }
901 	    if (parseKeywords[keywd].spec == SP_WAIT) {
902 		/*
903 		 * We add a .WAIT node in the dependency list.
904 		 * After any dynamic dependencies (and filename globbing)
905 		 * have happened, it is given a dependency on the each
906 		 * previous child back to and previous .WAIT node.
907 		 * The next child won't be scheduled until the .WAIT node
908 		 * is built.
909 		 * We give each .WAIT node a unique name (mainly for diag).
910 		 */
911 		snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
912 		gn = Targ_NewInternalNode(wait_src);
913 		if (doing_depend)
914 		    ParseMark(gn);
915 		gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
916 		LinkToTargets(gn, specType != SP_NOT);
917 		return TRUE;
918 	    }
919 	}
920     }
921     return FALSE;
922 }
923 
924 static void
925 ParseDoSrcMain(const char *src)
926 {
927     /*
928      * If we have noted the existence of a .MAIN, it means we need
929      * to add the sources of said target to the list of things
930      * to create. The string 'src' is likely to be free, so we
931      * must make a new copy of it. Note that this will only be
932      * invoked if the user didn't specify a target on the command
933      * line. This is to allow #ifmake's to succeed, or something...
934      */
935     Lst_Append(opts.create, bmake_strdup(src));
936     /*
937      * Add the name to the .TARGETS variable as well, so the user can
938      * employ that, if desired.
939      */
940     Var_Append(".TARGETS", src, VAR_GLOBAL);
941 }
942 
943 static void
944 ParseDoSrcOrder(const char *src)
945 {
946     GNode *gn;
947     /*
948      * Create proper predecessor/successor links between the previous
949      * source and the current one.
950      */
951     gn = Targ_GetNode(src);
952     if (doing_depend)
953 	ParseMark(gn);
954     if (order_pred != NULL) {
955 	Lst_Append(order_pred->order_succ, gn);
956 	Lst_Append(gn->order_pred, order_pred);
957 	if (DEBUG(PARSE)) {
958 	    debug_printf("# %s: added Order dependency %s - %s\n",
959 			 __func__, order_pred->name, gn->name);
960 	    Targ_PrintNode(order_pred, 0);
961 	    Targ_PrintNode(gn, 0);
962 	}
963     }
964     /*
965      * The current source now becomes the predecessor for the next one.
966      */
967     order_pred = gn;
968 }
969 
970 static void
971 ParseDoSrcOther(const char *src, GNodeType tOp, ParseSpecial specType)
972 {
973     GNode *gn;
974 
975     /*
976      * If the source is not an attribute, we need to find/create
977      * a node for it. After that we can apply any operator to it
978      * from a special target or link it to its parents, as
979      * appropriate.
980      *
981      * In the case of a source that was the object of a :: operator,
982      * the attribute is applied to all of its instances (as kept in
983      * the 'cohorts' list of the node) or all the cohorts are linked
984      * to all the targets.
985      */
986 
987     /* Find/create the 'src' node and attach to all targets */
988     gn = Targ_GetNode(src);
989     if (doing_depend)
990 	ParseMark(gn);
991     if (tOp) {
992 	gn->type |= tOp;
993     } else {
994 	LinkToTargets(gn, specType != SP_NOT);
995     }
996 }
997 
998 /* Given the name of a source in a dependency line, figure out if it is an
999  * attribute (such as .SILENT) and apply it to the targets if it is. Else
1000  * decide if there is some attribute which should be applied *to* the source
1001  * because of some special target (such as .PHONY) and apply it if so.
1002  * Otherwise, make the source a child of the targets in the list 'targets'.
1003  *
1004  * Input:
1005  *	tOp		operator (if any) from special targets
1006  *	src		name of the source to handle
1007  */
1008 static void
1009 ParseDoSrc(GNodeType tOp, const char *src, ParseSpecial specType)
1010 {
1011     if (ParseDoSrcKeyword(src, specType))
1012 	return;
1013 
1014     if (specType == SP_MAIN)
1015 	ParseDoSrcMain(src);
1016     else if (specType == SP_ORDER)
1017 	ParseDoSrcOrder(src);
1018     else
1019 	ParseDoSrcOther(src, tOp, specType);
1020 }
1021 
1022 /* If we have yet to decide on a main target to make, in the absence of any
1023  * user input, we want the first target on the first dependency line that is
1024  * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made. */
1025 static void
1026 FindMainTarget(void)
1027 {
1028     GNodeListNode *ln;
1029 
1030     if (mainNode != NULL)
1031 	return;
1032 
1033     for (ln = targets->first; ln != NULL; ln = ln->next) {
1034 	GNode *gn = ln->datum;
1035 	if (!(gn->type & OP_NOTARGET)) {
1036 	    mainNode = gn;
1037 	    Targ_SetMain(gn);
1038 	    return;
1039 	}
1040     }
1041 }
1042 
1043 /*
1044  * We got to the end of the line while we were still looking at targets.
1045  *
1046  * Ending a dependency line without an operator is a Bozo no-no.  As a
1047  * heuristic, this is also often triggered by undetected conflicts from
1048  * cvs/rcs merges.
1049  */
1050 static void
1051 ParseErrorNoDependency(const char *lstart)
1052 {
1053     if ((strncmp(lstart, "<<<<<<", 6) == 0) ||
1054 	(strncmp(lstart, "======", 6) == 0) ||
1055 	(strncmp(lstart, ">>>>>>", 6) == 0))
1056 	Parse_Error(PARSE_FATAL,
1057 		    "Makefile appears to contain unresolved cvs/rcs/??? merge conflicts");
1058     else if (lstart[0] == '.') {
1059 	const char *dirstart = lstart + 1;
1060 	const char *dirend;
1061 	cpp_skip_whitespace(&dirstart);
1062 	dirend = dirstart;
1063 	while (ch_isalnum(*dirend) || *dirend == '-')
1064 	    dirend++;
1065 	Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
1066 		    (int)(dirend - dirstart), dirstart);
1067     } else
1068 	Parse_Error(PARSE_FATAL, "Need an operator");
1069 }
1070 
1071 static void
1072 ParseDependencyTargetWord(/*const*/ char **pp, const char *lstart)
1073 {
1074     /*const*/ char *cp = *pp;
1075 
1076     while (*cp != '\0') {
1077 	if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' || *cp == '(') &&
1078 	    !ParseIsEscaped(lstart, cp))
1079 	    break;
1080 
1081 	if (*cp == '$') {
1082 	    /*
1083 	     * Must be a dynamic source (would have been expanded
1084 	     * otherwise), so call the Var module to parse the puppy
1085 	     * so we can safely advance beyond it...There should be
1086 	     * no errors in this, as they would have been discovered
1087 	     * in the initial Var_Subst and we wouldn't be here.
1088 	     */
1089 	    const char *nested_p = cp;
1090 	    const char *nested_val;
1091 	    void *freeIt;
1092 
1093 	    (void)Var_Parse(&nested_p, VAR_CMDLINE, VARE_UNDEFERR|VARE_WANTRES,
1094 			    &nested_val, &freeIt);
1095 	    /* TODO: handle errors */
1096 	    free(freeIt);
1097 	    cp += nested_p - cp;
1098 	} else
1099 	    cp++;
1100     }
1101 
1102     *pp = cp;
1103 }
1104 
1105 /*
1106  * Certain special targets have special semantics:
1107  *	.PATH		Have to set the dirSearchPath
1108  *			variable too
1109  *	.MAIN		Its sources are only used if
1110  *			nothing has been specified to
1111  *			create.
1112  *	.DEFAULT	Need to create a node to hang
1113  *			commands on, but we don't want
1114  *			it in the graph, nor do we want
1115  *			it to be the Main Target, so we
1116  *			create it, set OP_NOTMAIN and
1117  *			add it to the list, setting
1118  *			DEFAULT to the new node for
1119  *			later use. We claim the node is
1120  *			A transformation rule to make
1121  *			life easier later, when we'll
1122  *			use Make_HandleUse to actually
1123  *			apply the .DEFAULT commands.
1124  *	.PHONY		The list of targets
1125  *	.NOPATH		Don't search for file in the path
1126  *	.STALE
1127  *	.BEGIN
1128  *	.END
1129  *	.ERROR
1130  *	.DELETE_ON_ERROR
1131  *	.INTERRUPT	Are not to be considered the
1132  *			main target.
1133  *	.NOTPARALLEL	Make only one target at a time.
1134  *	.SINGLESHELL	Create a shell for each command.
1135  *	.ORDER		Must set initial predecessor to NULL
1136  */
1137 static void
1138 ParseDoDependencyTargetSpecial(ParseSpecial *inout_specType,
1139 			       const char *line,
1140 			       SearchPathList **inout_paths)
1141 {
1142     switch (*inout_specType) {
1143     case SP_PATH:
1144 	if (*inout_paths == NULL) {
1145 	    *inout_paths = Lst_New();
1146 	}
1147 	Lst_Append(*inout_paths, dirSearchPath);
1148 	break;
1149     case SP_MAIN:
1150 	if (!Lst_IsEmpty(opts.create)) {
1151 	    *inout_specType = SP_NOT;
1152 	}
1153 	break;
1154     case SP_BEGIN:
1155     case SP_END:
1156     case SP_STALE:
1157     case SP_ERROR:
1158     case SP_INTERRUPT: {
1159 	GNode *gn = Targ_GetNode(line);
1160 	if (doing_depend)
1161 	    ParseMark(gn);
1162 	gn->type |= OP_NOTMAIN|OP_SPECIAL;
1163 	Lst_Append(targets, gn);
1164 	break;
1165     }
1166     case SP_DEFAULT: {
1167 	GNode *gn = Targ_NewGN(".DEFAULT");
1168 	gn->type |= OP_NOTMAIN|OP_TRANSFORM;
1169 	Lst_Append(targets, gn);
1170 	DEFAULT = gn;
1171 	break;
1172     }
1173     case SP_DELETE_ON_ERROR:
1174 	deleteOnError = TRUE;
1175 	break;
1176     case SP_NOTPARALLEL:
1177 	opts.maxJobs = 1;
1178 	break;
1179     case SP_SINGLESHELL:
1180 	opts.compatMake = TRUE;
1181 	break;
1182     case SP_ORDER:
1183 	order_pred = NULL;
1184 	break;
1185     default:
1186 	break;
1187     }
1188 }
1189 
1190 /*
1191  * .PATH<suffix> has to be handled specially.
1192  * Call on the suffix module to give us a path to modify.
1193  */
1194 static Boolean
1195 ParseDoDependencyTargetPath(const char *line, SearchPathList **inout_paths)
1196 {
1197     SearchPath *path;
1198 
1199     path = Suff_GetPath(&line[5]);
1200     if (path == NULL) {
1201 	Parse_Error(PARSE_FATAL,
1202 		    "Suffix '%s' not defined (yet)",
1203 		    &line[5]);
1204 	return FALSE;
1205     } else {
1206 	if (*inout_paths == NULL) {
1207 	    *inout_paths = Lst_New();
1208 	}
1209 	Lst_Append(*inout_paths, path);
1210     }
1211     return TRUE;
1212 }
1213 
1214 /*
1215  * See if it's a special target and if so set specType to match it.
1216  */
1217 static Boolean
1218 ParseDoDependencyTarget(const char *line, ParseSpecial *inout_specType,
1219 			GNodeType *out_tOp, SearchPathList **inout_paths)
1220 {
1221     int keywd;
1222 
1223     if (!(*line == '.' && ch_isupper(line[1])))
1224 	return TRUE;
1225 
1226     /*
1227      * See if the target is a special target that must have it
1228      * or its sources handled specially.
1229      */
1230     keywd = ParseFindKeyword(line);
1231     if (keywd != -1) {
1232 	if (*inout_specType == SP_PATH && parseKeywords[keywd].spec != SP_PATH) {
1233 	    Parse_Error(PARSE_FATAL, "Mismatched special targets");
1234 	    return FALSE;
1235 	}
1236 
1237 	*inout_specType = parseKeywords[keywd].spec;
1238 	*out_tOp = parseKeywords[keywd].op;
1239 
1240 	ParseDoDependencyTargetSpecial(inout_specType, line, inout_paths);
1241 
1242     } else if (strncmp(line, ".PATH", 5) == 0) {
1243 	*inout_specType = SP_PATH;
1244 	if (!ParseDoDependencyTargetPath(line, inout_paths))
1245 	    return FALSE;
1246     }
1247     return TRUE;
1248 }
1249 
1250 static void
1251 ParseDoDependencyTargetMundane(char *line, StringList *curTargs)
1252 {
1253     if (Dir_HasWildcards(line)) {
1254 	/*
1255 	 * Targets are to be sought only in the current directory,
1256 	 * so create an empty path for the thing. Note we need to
1257 	 * use Dir_Destroy in the destruction of the path as the
1258 	 * Dir module could have added a directory to the path...
1259 	 */
1260 	SearchPath *emptyPath = Lst_New();
1261 
1262 	Dir_Expand(line, emptyPath, curTargs);
1263 
1264 	Lst_Destroy(emptyPath, Dir_Destroy);
1265     } else {
1266 	/*
1267 	 * No wildcards, but we want to avoid code duplication,
1268 	 * so create a list with the word on it.
1269 	 */
1270 	Lst_Append(curTargs, line);
1271     }
1272 
1273     /* Apply the targets. */
1274 
1275     while (!Lst_IsEmpty(curTargs)) {
1276 	char *targName = Lst_Dequeue(curTargs);
1277 	GNode *gn = Suff_IsTransform(targName)
1278 		    ? Suff_AddTransform(targName)
1279 		    : Targ_GetNode(targName);
1280 	if (doing_depend)
1281 	    ParseMark(gn);
1282 
1283 	Lst_Append(targets, gn);
1284     }
1285 }
1286 
1287 static void
1288 ParseDoDependencyTargetExtraWarn(char **pp, const char *lstart)
1289 {
1290     Boolean warning = FALSE;
1291     char *cp = *pp;
1292 
1293     while (*cp && (ParseIsEscaped(lstart, cp) ||
1294 		   (*cp != '!' && *cp != ':'))) {
1295 	if (ParseIsEscaped(lstart, cp) ||
1296 	    (*cp != ' ' && *cp != '\t')) {
1297 	    warning = TRUE;
1298 	}
1299 	cp++;
1300     }
1301     if (warning) {
1302 	Parse_Error(PARSE_WARNING, "Extra target ignored");
1303     }
1304     *pp = cp;
1305 }
1306 
1307 static void
1308 ParseDoDependencyCheckSpec(ParseSpecial specType)
1309 {
1310     switch (specType) {
1311     default:
1312 	Parse_Error(PARSE_WARNING,
1313 		    "Special and mundane targets don't mix. Mundane ones ignored");
1314 	break;
1315     case SP_DEFAULT:
1316     case SP_STALE:
1317     case SP_BEGIN:
1318     case SP_END:
1319     case SP_ERROR:
1320     case SP_INTERRUPT:
1321 	/*
1322 	 * These four create nodes on which to hang commands, so
1323 	 * targets shouldn't be empty...
1324 	 */
1325     case SP_NOT:
1326 	/*
1327 	 * Nothing special here -- targets can be empty if it wants.
1328 	 */
1329 	break;
1330     }
1331 }
1332 
1333 static Boolean
1334 ParseDoDependencyParseOp(char **pp, const char *lstart, GNodeType *out_op)
1335 {
1336     const char *cp = *pp;
1337 
1338     if (*cp == '!') {
1339 	*out_op = OP_FORCE;
1340 	(*pp)++;
1341 	return TRUE;
1342     }
1343 
1344     if (*cp == ':') {
1345 	if (cp[1] == ':') {
1346 	    *out_op = OP_DOUBLEDEP;
1347 	    (*pp) += 2;
1348 	} else {
1349 	    *out_op = OP_DEPENDS;
1350 	    (*pp)++;
1351 	}
1352 	return TRUE;
1353     }
1354 
1355     {
1356 	const char *msg = lstart[0] == '.' ? "Unknown directive"
1357 					   : "Missing dependency operator";
1358 	Parse_Error(PARSE_FATAL, "%s", msg);
1359 	return FALSE;
1360     }
1361 }
1362 
1363 static void
1364 ClearPaths(SearchPathList *paths)
1365 {
1366     if (paths != NULL) {
1367 	SearchPathListNode *ln;
1368 	for (ln = paths->first; ln != NULL; ln = ln->next)
1369 	    Dir_ClearPath(ln->datum);
1370     }
1371 
1372     Dir_SetPATH();
1373 }
1374 
1375 static void
1376 ParseDoDependencySourcesEmpty(ParseSpecial specType, SearchPathList *paths)
1377 {
1378     switch (specType) {
1379     case SP_SUFFIXES:
1380 	Suff_ClearSuffixes();
1381 	break;
1382     case SP_PRECIOUS:
1383 	allPrecious = TRUE;
1384 	break;
1385     case SP_IGNORE:
1386 	opts.ignoreErrors = TRUE;
1387 	break;
1388     case SP_SILENT:
1389 	opts.beSilent = TRUE;
1390 	break;
1391     case SP_PATH:
1392 	ClearPaths(paths);
1393 	break;
1394 #ifdef POSIX
1395     case SP_POSIX:
1396 	Var_Set("%POSIX", "1003.2", VAR_GLOBAL);
1397 	break;
1398 #endif
1399     default:
1400 	break;
1401     }
1402 }
1403 
1404 static void
1405 AddToPaths(const char *dir, SearchPathList *paths)
1406 {
1407     if (paths != NULL) {
1408 	SearchPathListNode *ln;
1409 	for (ln = paths->first; ln != NULL; ln = ln->next)
1410 	    (void)Dir_AddDir(ln->datum, dir);
1411     }
1412 }
1413 
1414 /*
1415  * If the target was one that doesn't take files as its sources
1416  * but takes something like suffixes, we take each
1417  * space-separated word on the line as a something and deal
1418  * with it accordingly.
1419  *
1420  * If the target was .SUFFIXES, we take each source as a
1421  * suffix and add it to the list of suffixes maintained by the
1422  * Suff module.
1423  *
1424  * If the target was a .PATH, we add the source as a directory
1425  * to search on the search path.
1426  *
1427  * If it was .INCLUDES, the source is taken to be the suffix of
1428  * files which will be #included and whose search path should
1429  * be present in the .INCLUDES variable.
1430  *
1431  * If it was .LIBS, the source is taken to be the suffix of
1432  * files which are considered libraries and whose search path
1433  * should be present in the .LIBS variable.
1434  *
1435  * If it was .NULL, the source is the suffix to use when a file
1436  * has no valid suffix.
1437  *
1438  * If it was .OBJDIR, the source is a new definition for .OBJDIR,
1439  * and will cause make to do a new chdir to that path.
1440  */
1441 static void
1442 ParseDoDependencySourceSpecial(ParseSpecial specType, char *word,
1443 			       SearchPathList *paths)
1444 {
1445     switch (specType) {
1446     case SP_SUFFIXES:
1447 	Suff_AddSuffix(word, &mainNode);
1448 	break;
1449     case SP_PATH:
1450 	AddToPaths(word, paths);
1451 	break;
1452     case SP_INCLUDES:
1453 	Suff_AddInclude(word);
1454 	break;
1455     case SP_LIBS:
1456 	Suff_AddLib(word);
1457 	break;
1458     case SP_NULL:
1459 	Suff_SetNull(word);
1460 	break;
1461     case SP_OBJDIR:
1462 	Main_SetObjdir("%s", word);
1463 	break;
1464     default:
1465 	break;
1466     }
1467 }
1468 
1469 static Boolean
1470 ParseDoDependencyTargets(char **inout_cp,
1471 			 char **inout_line,
1472 			 const char *lstart,
1473 			 ParseSpecial *inout_specType,
1474 			 GNodeType *inout_tOp,
1475 			 SearchPathList **inout_paths,
1476 			 StringList *curTargs)
1477 {
1478     char *cp = *inout_cp;
1479     char *line = *inout_line;
1480     char savec;
1481 
1482     for (;;) {
1483 	/*
1484 	 * Here LINE points to the beginning of the next word, and
1485 	 * LSTART points to the actual beginning of the line.
1486 	 */
1487 
1488 	/* Find the end of the next word. */
1489 	cp = line;
1490 	ParseDependencyTargetWord(&cp, lstart);
1491 
1492 	/*
1493 	 * If the word is followed by a left parenthesis, it's the
1494 	 * name of an object file inside an archive (ar file).
1495 	 */
1496 	if (!ParseIsEscaped(lstart, cp) && *cp == '(') {
1497 	    /*
1498 	     * Archives must be handled specially to make sure the OP_ARCHV
1499 	     * flag is set in their 'type' field, for one thing, and because
1500 	     * things like "archive(file1.o file2.o file3.o)" are permissible.
1501 	     * Arch_ParseArchive will set 'line' to be the first non-blank
1502 	     * after the archive-spec. It creates/finds nodes for the members
1503 	     * and places them on the given list, returning TRUE if all
1504 	     * went well and FALSE if there was an error in the
1505 	     * specification. On error, line should remain untouched.
1506 	     */
1507 	    if (!Arch_ParseArchive(&line, targets, VAR_CMDLINE)) {
1508 		Parse_Error(PARSE_FATAL,
1509 			    "Error in archive specification: \"%s\"", line);
1510 		return FALSE;
1511 	    } else {
1512 		/* Done with this word; on to the next. */
1513 		cp = line;
1514 		continue;
1515 	    }
1516 	}
1517 
1518 	if (!*cp) {
1519 	    ParseErrorNoDependency(lstart);
1520 	    return FALSE;
1521 	}
1522 
1523 	/* Insert a null terminator. */
1524 	savec = *cp;
1525 	*cp = '\0';
1526 
1527 	if (!ParseDoDependencyTarget(line, inout_specType, inout_tOp,
1528 				     inout_paths))
1529 	    return FALSE;
1530 
1531 	/*
1532 	 * Have word in line. Get or create its node and stick it at
1533 	 * the end of the targets list
1534 	 */
1535 	if (*inout_specType == SP_NOT && *line != '\0') {
1536 	    ParseDoDependencyTargetMundane(line, curTargs);
1537 	} else if (*inout_specType == SP_PATH && *line != '.' && *line != '\0') {
1538 	    Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", line);
1539 	}
1540 
1541 	/* Don't need the inserted null terminator any more. */
1542 	*cp = savec;
1543 
1544 	/*
1545 	 * If it is a special type and not .PATH, it's the only target we
1546 	 * allow on this line...
1547 	 */
1548 	if (*inout_specType != SP_NOT && *inout_specType != SP_PATH) {
1549 	    ParseDoDependencyTargetExtraWarn(&cp, lstart);
1550 	} else {
1551 	    pp_skip_whitespace(&cp);
1552 	}
1553 	line = cp;
1554 	if (*line == '\0')
1555 	    break;
1556 	if ((*line == '!' || *line == ':') && !ParseIsEscaped(lstart, line))
1557 	    break;
1558     }
1559 
1560     *inout_cp = cp;
1561     *inout_line = line;
1562     return TRUE;
1563 }
1564 
1565 static void
1566 ParseDoDependencySourcesSpecial(char *start, char *end,
1567 				ParseSpecial specType, SearchPathList *paths)
1568 {
1569     char savec;
1570 
1571     while (*start) {
1572 	while (*end && !ch_isspace(*end))
1573 	    end++;
1574 	savec = *end;
1575 	*end = '\0';
1576 	ParseDoDependencySourceSpecial(specType, start, paths);
1577 	*end = savec;
1578 	if (savec != '\0')
1579 	    end++;
1580 	pp_skip_whitespace(&end);
1581 	start = end;
1582     }
1583 }
1584 
1585 static Boolean
1586 ParseDoDependencySourcesMundane(char *start, char *end,
1587 				ParseSpecial specType, GNodeType tOp)
1588 {
1589     while (*start) {
1590 	/*
1591 	 * The targets take real sources, so we must beware of archive
1592 	 * specifications (i.e. things with left parentheses in them)
1593 	 * and handle them accordingly.
1594 	 */
1595 	for (; *end && !ch_isspace(*end); end++) {
1596 	    if (*end == '(' && end > start && end[-1] != '$') {
1597 		/*
1598 		 * Only stop for a left parenthesis if it isn't at the
1599 		 * start of a word (that'll be for variable changes
1600 		 * later) and isn't preceded by a dollar sign (a dynamic
1601 		 * source).
1602 		 */
1603 		break;
1604 	    }
1605 	}
1606 
1607 	if (*end == '(') {
1608 	    GNodeList *sources = Lst_New();
1609 	    if (!Arch_ParseArchive(&start, sources, VAR_CMDLINE)) {
1610 		Parse_Error(PARSE_FATAL,
1611 			    "Error in source archive spec \"%s\"", start);
1612 		return FALSE;
1613 	    }
1614 
1615 	    while (!Lst_IsEmpty(sources)) {
1616 		GNode *gn = Lst_Dequeue(sources);
1617 		ParseDoSrc(tOp, gn->name, specType);
1618 	    }
1619 	    Lst_Free(sources);
1620 	    end = start;
1621 	} else {
1622 	    if (*end) {
1623 		*end = '\0';
1624 		end++;
1625 	    }
1626 
1627 	    ParseDoSrc(tOp, start, specType);
1628 	}
1629 	pp_skip_whitespace(&end);
1630 	start = end;
1631     }
1632     return TRUE;
1633 }
1634 
1635 /* Parse a dependency line consisting of targets, followed by a dependency
1636  * operator, optionally followed by sources.
1637  *
1638  * The nodes of the sources are linked as children to the nodes of the
1639  * targets. Nodes are created as necessary.
1640  *
1641  * The operator is applied to each node in the global 'targets' list,
1642  * which is where the nodes found for the targets are kept, by means of
1643  * the ParseDoOp function.
1644  *
1645  * The sources are parsed in much the same way as the targets, except
1646  * that they are expanded using the wildcarding scheme of the C-Shell,
1647  * and all instances of the resulting words in the list of all targets
1648  * are found. Each of the resulting nodes is then linked to each of the
1649  * targets as one of its children.
1650  *
1651  * Certain targets and sources such as .PHONY or .PRECIOUS are handled
1652  * specially. These are the ones detailed by the specType variable.
1653  *
1654  * The storing of transformation rules such as '.c.o' is also taken care of
1655  * here. A target is recognized as a transformation rule by calling
1656  * Suff_IsTransform. If it is a transformation rule, its node is gotten
1657  * from the suffix module via Suff_AddTransform rather than the standard
1658  * Targ_FindNode in the target module.
1659  */
1660 static void
1661 ParseDoDependency(char *line)
1662 {
1663     char *cp;			/* our current position */
1664     GNodeType op;		/* the operator on the line */
1665     SearchPathList *paths;	/* search paths to alter when parsing
1666 				 * a list of .PATH targets */
1667     int tOp;			/* operator from special target */
1668     StringList *curTargs;	/* target names to be found and added
1669 				 * to the targets list */
1670     char *lstart = line;
1671 
1672     /*
1673      * specType contains the SPECial TYPE of the current target. It is SP_NOT
1674      * if the target is unspecial. If it *is* special, however, the children
1675      * are linked as children of the parent but not vice versa.
1676      */
1677     ParseSpecial specType = SP_NOT;
1678 
1679     DEBUG1(PARSE, "ParseDoDependency(%s)\n", line);
1680     tOp = 0;
1681 
1682     paths = NULL;
1683 
1684     curTargs = Lst_New();
1685 
1686     /*
1687      * First, grind through the targets.
1688      */
1689     if (!ParseDoDependencyTargets(&cp, &line, lstart, &specType, &tOp, &paths,
1690 				  curTargs))
1691 	goto out;
1692 
1693     /*
1694      * Don't need the list of target names anymore...
1695      */
1696     Lst_Free(curTargs);
1697     curTargs = NULL;
1698 
1699     if (!Lst_IsEmpty(targets))
1700 	ParseDoDependencyCheckSpec(specType);
1701 
1702     /*
1703      * Have now parsed all the target names. Must parse the operator next.
1704      */
1705     if (!ParseDoDependencyParseOp(&cp, lstart, &op))
1706 	goto out;
1707 
1708     /*
1709      * Apply the operator to the target. This is how we remember which
1710      * operator a target was defined with. It fails if the operator
1711      * used isn't consistent across all references.
1712      */
1713     ApplyDependencyOperator(op);
1714 
1715     /*
1716      * Onward to the sources.
1717      *
1718      * LINE will now point to the first source word, if any, or the
1719      * end of the string if not.
1720      */
1721     pp_skip_whitespace(&cp);
1722     line = cp;
1723 
1724     /*
1725      * Several special targets take different actions if present with no
1726      * sources:
1727      *	a .SUFFIXES line with no sources clears out all old suffixes
1728      *	a .PRECIOUS line makes all targets precious
1729      *	a .IGNORE line ignores errors for all targets
1730      *	a .SILENT line creates silence when making all targets
1731      *	a .PATH removes all directories from the search path(s).
1732      */
1733     if (!*line) {
1734 	ParseDoDependencySourcesEmpty(specType, paths);
1735     } else if (specType == SP_MFLAGS) {
1736 	/*
1737 	 * Call on functions in main.c to deal with these arguments and
1738 	 * set the initial character to a null-character so the loop to
1739 	 * get sources won't get anything
1740 	 */
1741 	Main_ParseArgLine(line);
1742 	*line = '\0';
1743     } else if (specType == SP_SHELL) {
1744 	if (!Job_ParseShell(line)) {
1745 	    Parse_Error(PARSE_FATAL, "improper shell specification");
1746 	    goto out;
1747 	}
1748 	*line = '\0';
1749     } else if (specType == SP_NOTPARALLEL || specType == SP_SINGLESHELL ||
1750 	       specType == SP_DELETE_ON_ERROR) {
1751 	*line = '\0';
1752     }
1753 
1754     /*
1755      * NOW GO FOR THE SOURCES
1756      */
1757     if (specType == SP_SUFFIXES || specType == SP_PATH ||
1758 	specType == SP_INCLUDES || specType == SP_LIBS ||
1759 	specType == SP_NULL || specType == SP_OBJDIR)
1760     {
1761 	ParseDoDependencySourcesSpecial(line, cp, specType, paths);
1762 	if (paths) {
1763 	    Lst_Free(paths);
1764 	    paths = NULL;
1765 	}
1766 	if (specType == SP_PATH)
1767 	    Dir_SetPATH();
1768     } else {
1769 	assert(paths == NULL);
1770 	if (!ParseDoDependencySourcesMundane(line, cp, specType, tOp))
1771 	    goto out;
1772     }
1773 
1774     FindMainTarget();
1775 
1776 out:
1777     if (paths != NULL)
1778 	Lst_Free(paths);
1779     if (curTargs != NULL)
1780 	Lst_Free(curTargs);
1781 }
1782 
1783 typedef struct VarAssignParsed {
1784     const char *nameStart;	/* unexpanded */
1785     const char *nameEnd;	/* before operator adjustment */
1786     const char *eq;		/* the '=' of the assignment operator */
1787 } VarAssignParsed;
1788 
1789 /* Determine the assignment operator and adjust the end of the variable
1790  * name accordingly. */
1791 static void
1792 AdjustVarassignOp(const VarAssignParsed *pvar, const char *value,
1793 		  VarAssign *out_var)
1794 {
1795     const char *op = pvar->eq;
1796     const char * const name = pvar->nameStart;
1797     VarAssignOp type;
1798 
1799     if (op > name && op[-1] == '+') {
1800 	type = VAR_APPEND;
1801 	op--;
1802 
1803     } else if (op > name && op[-1] == '?') {
1804 	op--;
1805 	type = VAR_DEFAULT;
1806 
1807     } else if (op > name && op[-1] == ':') {
1808 	op--;
1809 	type = VAR_SUBST;
1810 
1811     } else if (op > name && op[-1] == '!') {
1812 	op--;
1813 	type = VAR_SHELL;
1814 
1815     } else {
1816 	type = VAR_NORMAL;
1817 #ifdef SUNSHCMD
1818 	while (op > name && ch_isspace(op[-1]))
1819 	    op--;
1820 
1821 	if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
1822 	    type = VAR_SHELL;
1823 	    op -= 3;
1824 	}
1825 #endif
1826     }
1827 
1828     {
1829 	const char *nameEnd = pvar->nameEnd < op ? pvar->nameEnd : op;
1830 	out_var->varname = bmake_strsedup(pvar->nameStart, nameEnd);
1831 	out_var->op = type;
1832 	out_var->value = value;
1833     }
1834 }
1835 
1836 /* Parse a variable assignment, consisting of a single-word variable name,
1837  * optional whitespace, an assignment operator, optional whitespace and the
1838  * variable value.
1839  *
1840  * Note: There is a lexical ambiguity with assignment modifier characters
1841  * in variable names. This routine interprets the character before the =
1842  * as a modifier. Therefore, an assignment like
1843  *	C++=/usr/bin/CC
1844  * is interpreted as "C+ +=" instead of "C++ =".
1845  *
1846  * Used for both lines in a file and command line arguments. */
1847 Boolean
1848 Parse_IsVar(const char *p, VarAssign *out_var)
1849 {
1850     VarAssignParsed pvar;
1851     const char *firstSpace = NULL;
1852     char ch;
1853     int level = 0;
1854 
1855     /* Skip to variable name */
1856     while (*p == ' ' || *p == '\t')
1857 	p++;
1858 
1859     /* During parsing, the '+' of the '+=' operator is initially parsed
1860      * as part of the variable name.  It is later corrected, as is the ':sh'
1861      * modifier. Of these two (nameEnd and op), the earlier one determines the
1862      * actual end of the variable name. */
1863     pvar.nameStart = p;
1864 #ifdef CLEANUP
1865     pvar.nameEnd = NULL;
1866     pvar.eq = NULL;
1867 #endif
1868 
1869     /* Scan for one of the assignment operators outside a variable expansion */
1870     while ((ch = *p++) != 0) {
1871 	if (ch == '(' || ch == '{') {
1872 	    level++;
1873 	    continue;
1874 	}
1875 	if (ch == ')' || ch == '}') {
1876 	    level--;
1877 	    continue;
1878 	}
1879 
1880 	if (level != 0)
1881 	    continue;
1882 
1883 	if (ch == ' ' || ch == '\t')
1884 	    if (firstSpace == NULL)
1885 		firstSpace = p - 1;
1886 	while (ch == ' ' || ch == '\t')
1887 	    ch = *p++;
1888 
1889 #ifdef SUNSHCMD
1890 	if (ch == ':' && strncmp(p, "sh", 2) == 0) {
1891 	    p += 2;
1892 	    continue;
1893 	}
1894 #endif
1895 	if (ch == '=') {
1896 	    pvar.eq = p - 1;
1897 	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p - 1;
1898 	    cpp_skip_whitespace(&p);
1899 	    AdjustVarassignOp(&pvar, p, out_var);
1900 	    return TRUE;
1901 	}
1902 	if (*p == '=' && (ch == '+' || ch == ':' || ch == '?' || ch == '!')) {
1903 	    pvar.eq = p;
1904 	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p;
1905 	    p++;
1906 	    cpp_skip_whitespace(&p);
1907 	    AdjustVarassignOp(&pvar, p, out_var);
1908 	    return TRUE;
1909 	}
1910 	if (firstSpace != NULL)
1911 	    return FALSE;
1912     }
1913 
1914     return FALSE;
1915 }
1916 
1917 static void
1918 VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *ctxt)
1919 {
1920     if (DEBUG(LINT)) {
1921 	if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
1922 	    /* Check for syntax errors such as unclosed expressions or
1923 	     * unknown modifiers. */
1924 	    char *expandedValue;
1925 
1926 	    (void)Var_Subst(uvalue, ctxt, VARE_NONE, &expandedValue);
1927 	    /* TODO: handle errors */
1928 	    free(expandedValue);
1929 	}
1930     }
1931 }
1932 
1933 static void
1934 VarAssign_EvalSubst(const char *name, const char *uvalue, GNode *ctxt,
1935 		    const char **out_avalue, void **out_avalue_freeIt)
1936 {
1937     const char *avalue = uvalue;
1938     char *evalue;
1939     /*
1940      * Allow variables in the old value to be undefined, but leave their
1941      * expressions alone -- this is done by forcing oldVars to be false.
1942      * XXX: This can cause recursive variables, but that's not hard to do,
1943      * and this allows someone to do something like
1944      *
1945      *  CFLAGS = $(.INCLUDES)
1946      *  CFLAGS := -I.. $(CFLAGS)
1947      *
1948      * And not get an error.
1949      */
1950     Boolean oldOldVars = oldVars;
1951 
1952     oldVars = FALSE;
1953 
1954     /*
1955      * make sure that we set the variable the first time to nothing
1956      * so that it gets substituted!
1957      */
1958     if (!Var_Exists(name, ctxt))
1959 	Var_Set(name, "", ctxt);
1960 
1961     (void)Var_Subst(uvalue, ctxt, VARE_WANTRES|VARE_ASSIGN, &evalue);
1962     /* TODO: handle errors */
1963     oldVars = oldOldVars;
1964     avalue = evalue;
1965     Var_Set(name, avalue, ctxt);
1966 
1967     *out_avalue = avalue;
1968     *out_avalue_freeIt = evalue;
1969 }
1970 
1971 static void
1972 VarAssign_EvalShell(const char *name, const char *uvalue, GNode *ctxt,
1973 		    const char **out_avalue, void **out_avalue_freeIt)
1974 {
1975     const char *cmd, *errfmt;
1976     char *cmdOut;
1977     void *cmd_freeIt = NULL;
1978 
1979     cmd = uvalue;
1980     if (strchr(cmd, '$') != NULL) {
1981 	char *ecmd;
1982 	(void)Var_Subst(cmd, VAR_CMDLINE, VARE_UNDEFERR | VARE_WANTRES, &ecmd);
1983 	/* TODO: handle errors */
1984 	cmd = cmd_freeIt = ecmd;
1985     }
1986 
1987     cmdOut = Cmd_Exec(cmd, &errfmt);
1988     Var_Set(name, cmdOut, ctxt);
1989     *out_avalue = *out_avalue_freeIt = cmdOut;
1990 
1991     if (errfmt)
1992 	Parse_Error(PARSE_WARNING, errfmt, cmd);
1993 
1994     free(cmd_freeIt);
1995 }
1996 
1997 /* Perform a variable assignment.
1998  *
1999  * The actual value of the variable is returned in *out_avalue and
2000  * *out_avalue_freeIt.  Especially for VAR_SUBST and VAR_SHELL this can differ
2001  * from the literal value.
2002  *
2003  * Return whether the assignment was actually done.  The assignment is only
2004  * skipped if the operator is '?=' and the variable already exists. */
2005 static Boolean
2006 VarAssign_Eval(const char *name, VarAssignOp op, const char *uvalue,
2007 	       GNode *ctxt, const char **out_avalue, void **out_avalue_freeIt)
2008 {
2009     const char *avalue = uvalue;
2010     void *avalue_freeIt = NULL;
2011 
2012     if (op == VAR_APPEND) {
2013 	Var_Append(name, uvalue, ctxt);
2014     } else if (op == VAR_SUBST) {
2015 	VarAssign_EvalSubst(name, uvalue, ctxt, &avalue, &avalue_freeIt);
2016     } else if (op == VAR_SHELL) {
2017 	VarAssign_EvalShell(name, uvalue, ctxt, &avalue, &avalue_freeIt);
2018     } else {
2019 	if (op == VAR_DEFAULT && Var_Exists(name, ctxt)) {
2020 	    *out_avalue_freeIt = NULL;
2021 	    return FALSE;
2022 	}
2023 
2024 	/* Normal assignment -- just do it. */
2025 	Var_Set(name, uvalue, ctxt);
2026     }
2027 
2028     *out_avalue = avalue;
2029     *out_avalue_freeIt = avalue_freeIt;
2030     return TRUE;
2031 }
2032 
2033 static void
2034 VarAssignSpecial(const char *name, const char *avalue)
2035 {
2036     if (strcmp(name, MAKEOVERRIDES) == 0)
2037 	Main_ExportMAKEFLAGS(FALSE);	/* re-export MAKEFLAGS */
2038     else if (strcmp(name, ".CURDIR") == 0) {
2039 	/*
2040 	 * Someone is being (too?) clever...
2041 	 * Let's pretend they know what they are doing and
2042 	 * re-initialize the 'cur' CachedDir.
2043 	 */
2044 	Dir_InitCur(avalue);
2045 	Dir_SetPATH();
2046     } else if (strcmp(name, MAKE_JOB_PREFIX) == 0) {
2047 	Job_SetPrefix();
2048     } else if (strcmp(name, MAKE_EXPORTED) == 0) {
2049 	Var_Export(avalue, FALSE);
2050     }
2051 }
2052 
2053 /* Perform the variable variable assignment in the given context. */
2054 void
2055 Parse_DoVar(VarAssign *var, GNode *ctxt)
2056 {
2057     const char *avalue;		/* actual value (maybe expanded) */
2058     void *avalue_freeIt;
2059 
2060     VarCheckSyntax(var->op, var->value, ctxt);
2061     if (VarAssign_Eval(var->varname, var->op, var->value, ctxt,
2062 		       &avalue, &avalue_freeIt))
2063 	VarAssignSpecial(var->varname, avalue);
2064 
2065     free(avalue_freeIt);
2066     free(var->varname);
2067 }
2068 
2069 
2070 /*
2071  * ParseMaybeSubMake --
2072  *	Scan the command string to see if it a possible submake node
2073  * Input:
2074  *	cmd		the command to scan
2075  * Results:
2076  *	TRUE if the command is possibly a submake, FALSE if not.
2077  */
2078 static Boolean
2079 ParseMaybeSubMake(const char *cmd)
2080 {
2081     size_t i;
2082     static struct {
2083 	const char *name;
2084 	size_t len;
2085     } vals[] = {
2086 #define MKV(A)	{	A, sizeof(A) - 1	}
2087 	MKV("${MAKE}"),
2088 	MKV("${.MAKE}"),
2089 	MKV("$(MAKE)"),
2090 	MKV("$(.MAKE)"),
2091 	MKV("make"),
2092     };
2093     for (i = 0; i < sizeof vals / sizeof vals[0]; i++) {
2094 	char *ptr;
2095 	if ((ptr = strstr(cmd, vals[i].name)) == NULL)
2096 	    continue;
2097 	if ((ptr == cmd || !ch_isalnum(ptr[-1]))
2098 	    && !ch_isalnum(ptr[vals[i].len]))
2099 	    return TRUE;
2100     }
2101     return FALSE;
2102 }
2103 
2104 /* Append the command to the target node.
2105  *
2106  * The node may be marked as a submake node if the command is determined to
2107  * be that. */
2108 static void
2109 ParseAddCmd(GNode *gn, char *cmd)
2110 {
2111     /* Add to last (ie current) cohort for :: targets */
2112     if ((gn->type & OP_DOUBLEDEP) && gn->cohorts->last != NULL)
2113 	gn = gn->cohorts->last->datum;
2114 
2115     /* if target already supplied, ignore commands */
2116     if (!(gn->type & OP_HAS_COMMANDS)) {
2117 	Lst_Append(gn->commands, cmd);
2118 	if (ParseMaybeSubMake(cmd))
2119 	    gn->type |= OP_SUBMAKE;
2120 	ParseMark(gn);
2121     } else {
2122 #if 0
2123 	/* XXX: We cannot do this until we fix the tree */
2124 	Lst_Append(gn->commands, cmd);
2125 	Parse_Error(PARSE_WARNING,
2126 		     "overriding commands for target \"%s\"; "
2127 		     "previous commands defined at %s: %d ignored",
2128 		     gn->name, gn->fname, gn->lineno);
2129 #else
2130 	Parse_Error(PARSE_WARNING,
2131 		    "duplicate script for target \"%s\" ignored",
2132 		    gn->name);
2133 	ParseErrorInternal(gn->fname, (size_t)gn->lineno, PARSE_WARNING,
2134 			   "using previous script for \"%s\" defined here",
2135 			   gn->name);
2136 #endif
2137     }
2138 }
2139 
2140 /* Add a directory to the path searched for included makefiles bracketed
2141  * by double-quotes. */
2142 void
2143 Parse_AddIncludeDir(const char *dir)
2144 {
2145     (void)Dir_AddDir(parseIncPath, dir);
2146 }
2147 
2148 /* Push to another file.
2149  *
2150  * The input is the line minus the '.'. A file spec is a string enclosed in
2151  * <> or "". The <> file is looked for only in sysIncPath. The "" file is
2152  * first searched in the parsedir and then in the directories specified by
2153  * the -I command line options.
2154  */
2155 static void
2156 Parse_include_file(char *file, Boolean isSystem, Boolean depinc, int silent)
2157 {
2158     struct loadedfile *lf;
2159     char *fullname;		/* full pathname of file */
2160     char *newName;
2161     char *prefEnd, *incdir;
2162     int fd;
2163     int i;
2164 
2165     /*
2166      * Now we know the file's name and its search path, we attempt to
2167      * find the durn thing. A return of NULL indicates the file don't
2168      * exist.
2169      */
2170     fullname = file[0] == '/' ? bmake_strdup(file) : NULL;
2171 
2172     if (fullname == NULL && !isSystem) {
2173 	/*
2174 	 * Include files contained in double-quotes are first searched for
2175 	 * relative to the including file's location. We don't want to
2176 	 * cd there, of course, so we just tack on the old file's
2177 	 * leading path components and call Dir_FindFile to see if
2178 	 * we can locate the beast.
2179 	 */
2180 
2181 	incdir = bmake_strdup(CurFile()->fname);
2182 	prefEnd = strrchr(incdir, '/');
2183 	if (prefEnd != NULL) {
2184 	    *prefEnd = '\0';
2185 	    /* Now do lexical processing of leading "../" on the filename */
2186 	    for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
2187 		prefEnd = strrchr(incdir + 1, '/');
2188 		if (prefEnd == NULL || strcmp(prefEnd, "/..") == 0)
2189 		    break;
2190 		*prefEnd = '\0';
2191 	    }
2192 	    newName = str_concat3(incdir, "/", file + i);
2193 	    fullname = Dir_FindFile(newName, parseIncPath);
2194 	    if (fullname == NULL)
2195 		fullname = Dir_FindFile(newName, dirSearchPath);
2196 	    free(newName);
2197 	}
2198 	free(incdir);
2199 
2200 	if (fullname == NULL) {
2201 	    /*
2202 	     * Makefile wasn't found in same directory as included makefile.
2203 	     * Search for it first on the -I search path,
2204 	     * then on the .PATH search path, if not found in a -I directory.
2205 	     * If we have a suffix specific path we should use that.
2206 	     */
2207 	    char *suff;
2208 	    SearchPath *suffPath = NULL;
2209 
2210 	    if ((suff = strrchr(file, '.'))) {
2211 		suffPath = Suff_GetPath(suff);
2212 		if (suffPath != NULL) {
2213 		    fullname = Dir_FindFile(file, suffPath);
2214 		}
2215 	    }
2216 	    if (fullname == NULL) {
2217 		fullname = Dir_FindFile(file, parseIncPath);
2218 		if (fullname == NULL) {
2219 		    fullname = Dir_FindFile(file, dirSearchPath);
2220 		}
2221 	    }
2222 	}
2223     }
2224 
2225     /* Looking for a system file or file still not found */
2226     if (fullname == NULL) {
2227 	/*
2228 	 * Look for it on the system path
2229 	 */
2230 	SearchPath *path = Lst_IsEmpty(sysIncPath) ? defSysIncPath : sysIncPath;
2231 	fullname = Dir_FindFile(file, path);
2232     }
2233 
2234     if (fullname == NULL) {
2235 	if (!silent)
2236 	    Parse_Error(PARSE_FATAL, "Could not find %s", file);
2237 	return;
2238     }
2239 
2240     /* Actually open the file... */
2241     fd = open(fullname, O_RDONLY);
2242     if (fd == -1) {
2243 	if (!silent)
2244 	    Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
2245 	free(fullname);
2246 	return;
2247     }
2248 
2249     /* load it */
2250     lf = loadfile(fullname, fd);
2251 
2252     /* Start reading from this file next */
2253     Parse_SetInput(fullname, 0, -1, loadedfile_nextbuf, lf);
2254     CurFile()->lf = lf;
2255     if (depinc)
2256 	doing_depend = depinc;	/* only turn it on */
2257 }
2258 
2259 static void
2260 ParseDoInclude(char *line)
2261 {
2262     char endc;			/* the character which ends the file spec */
2263     char *cp;			/* current position in file spec */
2264     int silent = *line != 'i';
2265     char *file = line + (silent ? 8 : 7);
2266 
2267     /* Skip to delimiter character so we know where to look */
2268     while (*file == ' ' || *file == '\t')
2269 	file++;
2270 
2271     if (*file != '"' && *file != '<') {
2272 	Parse_Error(PARSE_FATAL,
2273 		    ".include filename must be delimited by '\"' or '<'");
2274 	return;
2275     }
2276 
2277     /*
2278      * Set the search path on which to find the include file based on the
2279      * characters which bracket its name. Angle-brackets imply it's
2280      * a system Makefile while double-quotes imply it's a user makefile
2281      */
2282     if (*file == '<') {
2283 	endc = '>';
2284     } else {
2285 	endc = '"';
2286     }
2287 
2288     /* Skip to matching delimiter */
2289     for (cp = ++file; *cp && *cp != endc; cp++)
2290 	continue;
2291 
2292     if (*cp != endc) {
2293 	Parse_Error(PARSE_FATAL,
2294 		    "Unclosed %cinclude filename. '%c' expected",
2295 		    '.', endc);
2296 	return;
2297     }
2298     *cp = '\0';
2299 
2300     /*
2301      * Substitute for any variables in the file name before trying to
2302      * find the thing.
2303      */
2304     (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &file);
2305     /* TODO: handle errors */
2306 
2307     Parse_include_file(file, endc == '>', *line == 'd', silent);
2308     free(file);
2309 }
2310 
2311 /* Split filename into dirname + basename, then assign these to the
2312  * given variables. */
2313 static void
2314 SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
2315 {
2316     const char *slash, *dirname, *basename;
2317     void *freeIt;
2318 
2319     slash = strrchr(filename, '/');
2320     if (slash == NULL) {
2321 	dirname = curdir;
2322 	basename = filename;
2323 	freeIt = NULL;
2324     } else {
2325 	dirname = freeIt = bmake_strsedup(filename, slash);
2326 	basename = slash + 1;
2327     }
2328 
2329     Var_Set(dirvar, dirname, VAR_GLOBAL);
2330     Var_Set(filevar, basename, VAR_GLOBAL);
2331 
2332     DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
2333 	   __func__, dirvar, dirname, filevar, basename);
2334     free(freeIt);
2335 }
2336 
2337 /* Return the immediately including file.
2338  *
2339  * This is made complicated since the .for loop is implemented as a special
2340  * kind of .include; see For_Run. */
2341 static const char *
2342 GetActuallyIncludingFile(void)
2343 {
2344     size_t i;
2345     const IFile *incs = GetInclude(0);
2346 
2347     for (i = includes.len; i >= 2; i--)
2348 	if (!incs[i - 1].fromForLoop)
2349 	    return incs[i - 2].fname;
2350     return NULL;
2351 }
2352 
2353 /* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
2354 static void
2355 ParseSetParseFile(const char *filename)
2356 {
2357     const char *including;
2358 
2359     SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");
2360 
2361     including = GetActuallyIncludingFile();
2362     if (including != NULL) {
2363 	SetFilenameVars(including,
2364 			".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
2365     } else {
2366 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
2367 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
2368     }
2369 }
2370 
2371 static Boolean
2372 StrContainsWord(const char *str, const char *word)
2373 {
2374     size_t strLen = strlen(str);
2375     size_t wordLen = strlen(word);
2376     const char *p, *end;
2377 
2378     if (strLen < wordLen)
2379 	return FALSE;		/* str is too short to contain word */
2380 
2381     end = str + strLen - wordLen;
2382     for (p = str; p != NULL; p = strchr(p, ' ')) {
2383 	if (*p == ' ')
2384 	    p++;
2385 	if (p > end)
2386 	    return FALSE;	/* cannot contain word */
2387 
2388 	if (memcmp(p, word, wordLen) == 0 &&
2389 	    (p[wordLen] == '\0' || p[wordLen] == ' '))
2390 	    return TRUE;
2391     }
2392     return FALSE;
2393 }
2394 
2395 /* XXX: Searching through a set of words with this linear search is
2396  * inefficient for variables that contain thousands of words. */
2397 static Boolean
2398 VarContainsWord(const char *varname, const char *word)
2399 {
2400     void *val_freeIt;
2401     const char *val = Var_Value(varname, VAR_GLOBAL, &val_freeIt);
2402     Boolean found = val != NULL && StrContainsWord(val, word);
2403     bmake_free(val_freeIt);
2404     return found;
2405 }
2406 
2407 /* Track the makefiles we read - so makefiles can set dependencies on them.
2408  * Avoid adding anything more than once. */
2409 static void
2410 ParseTrackInput(const char *name)
2411 {
2412     if (!VarContainsWord(MAKE_MAKEFILES, name))
2413 	Var_Append(MAKE_MAKEFILES, name, VAR_GLOBAL);
2414 }
2415 
2416 
2417 /* Start Parsing from the given source.
2418  *
2419  * The given file is added to the includes stack. */
2420 void
2421 Parse_SetInput(const char *name, int line, int fd,
2422 	       char *(*nextbuf)(void *, size_t *), void *arg)
2423 {
2424     IFile *curFile;
2425     char *buf;
2426     size_t len;
2427     Boolean fromForLoop = name == NULL;
2428 
2429     if (fromForLoop)
2430 	name = CurFile()->fname;
2431     else
2432 	ParseTrackInput(name);
2433 
2434     if (DEBUG(PARSE))
2435 	debug_printf("%s: file %s, line %d, fd %d, nextbuf %s, arg %p\n",
2436 		     __func__, name, line, fd,
2437 		     nextbuf == loadedfile_nextbuf ? "loadedfile" : "other",
2438 		     arg);
2439 
2440     if (fd == -1 && nextbuf == NULL)
2441 	/* sanity */
2442 	return;
2443 
2444     curFile = Vector_Push(&includes);
2445 
2446     /*
2447      * Once the previous state has been saved, we can get down to reading
2448      * the new file. We set up the name of the file to be the absolute
2449      * name of the include file so error messages refer to the right
2450      * place.
2451      */
2452     curFile->fname = bmake_strdup(name);
2453     curFile->fromForLoop = fromForLoop;
2454     curFile->lineno = line;
2455     curFile->first_lineno = line;
2456     curFile->nextbuf = nextbuf;
2457     curFile->nextbuf_arg = arg;
2458     curFile->lf = NULL;
2459     curFile->depending = doing_depend;	/* restore this on EOF */
2460 
2461     assert(nextbuf != NULL);
2462 
2463     /* Get first block of input data */
2464     buf = curFile->nextbuf(curFile->nextbuf_arg, &len);
2465     if (buf == NULL) {
2466 	/* Was all a waste of time ... */
2467 	if (curFile->fname)
2468 	    free(curFile->fname);
2469 	free(curFile);
2470 	return;
2471     }
2472     curFile->buf_freeIt = buf;
2473     curFile->buf_ptr = buf;
2474     curFile->buf_end = buf + len;
2475 
2476     curFile->cond_depth = Cond_save_depth();
2477     ParseSetParseFile(name);
2478 }
2479 
2480 /* Check if the directive is an include directive. */
2481 static Boolean
2482 IsInclude(const char *dir, Boolean sysv)
2483 {
2484 	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
2485 		dir++;
2486 
2487 	if (strncmp(dir, "include", 7) != 0)
2488 		return FALSE;
2489 
2490 	/* Space is not mandatory for BSD .include */
2491 	return !sysv || ch_isspace(dir[7]);
2492 }
2493 
2494 
2495 #ifdef SYSVINCLUDE
2496 /* Check if the line is a SYSV include directive. */
2497 static Boolean
2498 IsSysVInclude(const char *line)
2499 {
2500 	const char *p;
2501 
2502 	if (!IsInclude(line, TRUE))
2503 		return FALSE;
2504 
2505 	/* Avoid interpreting a dependency line as an include */
2506 	for (p = line; (p = strchr(p, ':')) != NULL;) {
2507 		if (*++p == '\0') {
2508 			/* end of line -> dependency */
2509 			return FALSE;
2510 		}
2511 		if (*p == ':' || ch_isspace(*p)) {
2512 			/* :: operator or ': ' -> dependency */
2513 			return FALSE;
2514 		}
2515 	}
2516 	return TRUE;
2517 }
2518 
2519 /* Push to another file.  The line points to the word "include". */
2520 static void
2521 ParseTraditionalInclude(char *line)
2522 {
2523     char *cp;			/* current position in file spec */
2524     int done = 0;
2525     int silent = line[0] != 'i';
2526     char *file = line + (silent ? 8 : 7);
2527     char *all_files;
2528 
2529     DEBUG2(PARSE, "%s: %s\n", __func__, file);
2530 
2531     pp_skip_whitespace(&file);
2532 
2533     /*
2534      * Substitute for any variables in the file name before trying to
2535      * find the thing.
2536      */
2537     (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &all_files);
2538     /* TODO: handle errors */
2539 
2540     if (*file == '\0') {
2541 	Parse_Error(PARSE_FATAL, "Filename missing from \"include\"");
2542 	goto out;
2543     }
2544 
2545     for (file = all_files; !done; file = cp + 1) {
2546 	/* Skip to end of line or next whitespace */
2547 	for (cp = file; *cp && !ch_isspace(*cp); cp++)
2548 	    continue;
2549 
2550 	if (*cp)
2551 	    *cp = '\0';
2552 	else
2553 	    done = 1;
2554 
2555 	Parse_include_file(file, FALSE, FALSE, silent);
2556     }
2557 out:
2558     free(all_files);
2559 }
2560 #endif
2561 
2562 #ifdef GMAKEEXPORT
2563 /* Parse "export <variable>=<value>", and actually export it. */
2564 static void
2565 ParseGmakeExport(char *line)
2566 {
2567     char *variable = line + 6;
2568     char *value;
2569 
2570     DEBUG2(PARSE, "%s: %s\n", __func__, variable);
2571 
2572     pp_skip_whitespace(&variable);
2573 
2574     for (value = variable; *value && *value != '='; value++)
2575 	continue;
2576 
2577     if (*value != '=') {
2578 	Parse_Error(PARSE_FATAL,
2579 		    "Variable/Value missing from \"export\"");
2580 	return;
2581     }
2582     *value++ = '\0';		/* terminate variable */
2583 
2584     /*
2585      * Expand the value before putting it in the environment.
2586      */
2587     (void)Var_Subst(value, VAR_CMDLINE, VARE_WANTRES, &value);
2588     /* TODO: handle errors */
2589 
2590     setenv(variable, value, 1);
2591     free(value);
2592 }
2593 #endif
2594 
2595 /* Called when EOF is reached in the current file. If we were reading an
2596  * include file, the includes stack is popped and things set up to go back
2597  * to reading the previous file at the previous location.
2598  *
2599  * Results:
2600  *	TRUE to continue parsing, i.e. it had only reached the end of an
2601  *	included file, FALSE if the main file has been parsed completely.
2602  */
2603 static Boolean
2604 ParseEOF(void)
2605 {
2606     char *ptr;
2607     size_t len;
2608     IFile *curFile = CurFile();
2609 
2610     assert(curFile->nextbuf != NULL);
2611 
2612     doing_depend = curFile->depending;	/* restore this */
2613     /* get next input buffer, if any */
2614     ptr = curFile->nextbuf(curFile->nextbuf_arg, &len);
2615     curFile->buf_ptr = ptr;
2616     curFile->buf_freeIt = ptr;
2617     curFile->buf_end = ptr + len;
2618     curFile->lineno = curFile->first_lineno;
2619     if (ptr != NULL) {
2620 	/* Iterate again */
2621 	return TRUE;
2622     }
2623 
2624     /* Ensure the makefile (or loop) didn't have mismatched conditionals */
2625     Cond_restore_depth(curFile->cond_depth);
2626 
2627     if (curFile->lf != NULL) {
2628 	loadedfile_destroy(curFile->lf);
2629 	curFile->lf = NULL;
2630     }
2631 
2632     /* Dispose of curFile info */
2633     /* Leak curFile->fname because all the gnodes have pointers to it */
2634     free(curFile->buf_freeIt);
2635     Vector_Pop(&includes);
2636 
2637     if (includes.len == 0) {
2638 	/* We've run out of input */
2639 	Var_Delete(".PARSEDIR", VAR_GLOBAL);
2640 	Var_Delete(".PARSEFILE", VAR_GLOBAL);
2641 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
2642 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
2643 	return FALSE;
2644     }
2645 
2646     curFile = CurFile();
2647     DEBUG2(PARSE, "ParseEOF: returning to file %s, line %d\n",
2648 	   curFile->fname, curFile->lineno);
2649 
2650     ParseSetParseFile(curFile->fname);
2651     return TRUE;
2652 }
2653 
2654 #define PARSE_RAW 1
2655 #define PARSE_SKIP 2
2656 
2657 static char *
2658 ParseGetLine(int flags)
2659 {
2660     IFile *cf = CurFile();
2661     char *ptr;
2662     char ch;
2663     char *line;
2664     char *line_end;
2665     char *escaped;
2666     char *comment;
2667     char *tp;
2668 
2669     /* Loop through blank lines and comment lines */
2670     for (;;) {
2671 	cf->lineno++;
2672 	line = cf->buf_ptr;
2673 	ptr = line;
2674 	line_end = line;
2675 	escaped = NULL;
2676 	comment = NULL;
2677 	for (;;) {
2678 	    /* XXX: can buf_end ever be null? */
2679 	    if (cf->buf_end != NULL && ptr == cf->buf_end) {
2680 		/* end of buffer */
2681 		ch = 0;
2682 		break;
2683 	    }
2684 	    ch = *ptr;
2685 	    if (ch == 0 || (ch == '\\' && ptr[1] == 0)) {
2686 		/* XXX: can buf_end ever be null? */
2687 		if (cf->buf_end == NULL)
2688 		    /* End of string (aka for loop) data */
2689 		    break;
2690 		/* see if there is more we can parse */
2691 		while (ptr++ < cf->buf_end) {
2692 		    if ((ch = *ptr) == '\n') {
2693 			if (ptr > line && ptr[-1] == '\\')
2694 			    continue;
2695 			Parse_Error(PARSE_WARNING,
2696 				    "Zero byte read from file, "
2697 				    "skipping rest of line.");
2698 			break;
2699 		    }
2700 		}
2701 		if (cf->nextbuf != NULL) {
2702 		    /*
2703 		     * End of this buffer; return EOF and outer logic
2704 		     * will get the next one. (eww)
2705 		     */
2706 		    break;
2707 		}
2708 		Parse_Error(PARSE_FATAL, "Zero byte read from file");
2709 		return NULL;
2710 	    }
2711 
2712 	    if (ch == '\\') {
2713 		/* Don't treat next character as special, remember first one */
2714 		if (escaped == NULL)
2715 		    escaped = ptr;
2716 		if (ptr[1] == '\n')
2717 		    cf->lineno++;
2718 		ptr += 2;
2719 		line_end = ptr;
2720 		continue;
2721 	    }
2722 	    if (ch == '#' && comment == NULL) {
2723 		/* Remember first '#' for comment stripping */
2724 		/* Unless previous char was '[', as in modifier :[#] */
2725 		if (!(ptr > line && ptr[-1] == '['))
2726 		    comment = line_end;
2727 	    }
2728 	    ptr++;
2729 	    if (ch == '\n')
2730 		break;
2731 	    if (!ch_isspace(ch))
2732 		/* We are not interested in trailing whitespace */
2733 		line_end = ptr;
2734 	}
2735 
2736 	/* Save next 'to be processed' location */
2737 	cf->buf_ptr = ptr;
2738 
2739 	/* Check we have a non-comment, non-blank line */
2740 	if (line_end == line || comment == line) {
2741 	    if (ch == 0)
2742 		/* At end of file */
2743 		return NULL;
2744 	    /* Parse another line */
2745 	    continue;
2746 	}
2747 
2748 	/* We now have a line of data */
2749 	*line_end = 0;
2750 
2751 	if (flags & PARSE_RAW) {
2752 	    /* Leave '\' (etc) in line buffer (eg 'for' lines) */
2753 	    return line;
2754 	}
2755 
2756 	if (flags & PARSE_SKIP) {
2757 	    /* Completely ignore non-directives */
2758 	    if (line[0] != '.')
2759 		continue;
2760 	    /* We could do more of the .else/.elif/.endif checks here */
2761 	}
2762 	break;
2763     }
2764 
2765     /* Brutally ignore anything after a non-escaped '#' in non-commands */
2766     if (comment != NULL && line[0] != '\t') {
2767 	line_end = comment;
2768 	*line_end = 0;
2769     }
2770 
2771     /* If we didn't see a '\\' then the in-situ data is fine */
2772     if (escaped == NULL)
2773 	return line;
2774 
2775     /* Remove escapes from '\n' and '#' */
2776     tp = ptr = escaped;
2777     escaped = line;
2778     for (; ; *tp++ = ch) {
2779 	ch = *ptr++;
2780 	if (ch != '\\') {
2781 	    if (ch == 0)
2782 		break;
2783 	    continue;
2784 	}
2785 
2786 	ch = *ptr++;
2787 	if (ch == 0) {
2788 	    /* Delete '\\' at end of buffer */
2789 	    tp--;
2790 	    break;
2791 	}
2792 
2793 	if (ch == '#' && line[0] != '\t')
2794 	    /* Delete '\\' from before '#' on non-command lines */
2795 	    continue;
2796 
2797 	if (ch != '\n') {
2798 	    /* Leave '\\' in buffer for later */
2799 	    *tp++ = '\\';
2800 	    /* Make sure we don't delete an escaped ' ' from the line end */
2801 	    escaped = tp + 1;
2802 	    continue;
2803 	}
2804 
2805 	/* Escaped '\n' replace following whitespace with a single ' ' */
2806 	while (ptr[0] == ' ' || ptr[0] == '\t')
2807 	    ptr++;
2808 	ch = ' ';
2809     }
2810 
2811     /* Delete any trailing spaces - eg from empty continuations */
2812     while (tp > escaped && ch_isspace(tp[-1]))
2813 	tp--;
2814 
2815     *tp = 0;
2816     return line;
2817 }
2818 
2819 /* Read an entire line from the input file. Called only by Parse_File.
2820  *
2821  * Results:
2822  *	A line without its newline.
2823  *
2824  * Side Effects:
2825  *	Only those associated with reading a character
2826  */
2827 static char *
2828 ParseReadLine(void)
2829 {
2830     char *line;			/* Result */
2831     int lineno;			/* Saved line # */
2832     int rval;
2833 
2834     for (;;) {
2835 	line = ParseGetLine(0);
2836 	if (line == NULL)
2837 	    return NULL;
2838 
2839 	if (line[0] != '.')
2840 	    return line;
2841 
2842 	/*
2843 	 * The line might be a conditional. Ask the conditional module
2844 	 * about it and act accordingly
2845 	 */
2846 	switch (Cond_EvalLine(line)) {
2847 	case COND_SKIP:
2848 	    /* Skip to next conditional that evaluates to COND_PARSE.  */
2849 	    do {
2850 		line = ParseGetLine(PARSE_SKIP);
2851 	    } while (line && Cond_EvalLine(line) != COND_PARSE);
2852 	    if (line == NULL)
2853 		break;
2854 	    continue;
2855 	case COND_PARSE:
2856 	    continue;
2857 	case COND_INVALID:    /* Not a conditional line */
2858 	    /* Check for .for loops */
2859 	    rval = For_Eval(line);
2860 	    if (rval == 0)
2861 		/* Not a .for line */
2862 		break;
2863 	    if (rval < 0)
2864 		/* Syntax error - error printed, ignore line */
2865 		continue;
2866 	    /* Start of a .for loop */
2867 	    lineno = CurFile()->lineno;
2868 	    /* Accumulate loop lines until matching .endfor */
2869 	    do {
2870 		line = ParseGetLine(PARSE_RAW);
2871 		if (line == NULL) {
2872 		    Parse_Error(PARSE_FATAL,
2873 				"Unexpected end of file in for loop.");
2874 		    break;
2875 		}
2876 	    } while (For_Accum(line));
2877 	    /* Stash each iteration as a new 'input file' */
2878 	    For_Run(lineno);
2879 	    /* Read next line from for-loop buffer */
2880 	    continue;
2881 	}
2882 	return line;
2883     }
2884 }
2885 
2886 static void
2887 FinishDependencyGroup(void)
2888 {
2889     if (targets != NULL) {
2890 	GNodeListNode *ln;
2891 	for (ln = targets->first; ln != NULL; ln = ln->next) {
2892 	    GNode *gn = ln->datum;
2893 
2894 	    Suff_EndTransform(gn);
2895 
2896 	    /* Mark the target as already having commands if it does, to
2897 	     * keep from having shell commands on multiple dependency lines. */
2898 	    if (!Lst_IsEmpty(gn->commands))
2899 		gn->type |= OP_HAS_COMMANDS;
2900 	}
2901 
2902 	Lst_Free(targets);
2903 	targets = NULL;
2904     }
2905 }
2906 
2907 /* Add the command to each target from the current dependency spec. */
2908 static void
2909 ParseLine_ShellCommand(const char *p)
2910 {
2911     cpp_skip_whitespace(&p);
2912     if (*p == '\0')
2913 	return;			/* skip empty commands */
2914 
2915     if (targets == NULL) {
2916 	Parse_Error(PARSE_FATAL, "Unassociated shell command \"%s\"", p);
2917 	return;
2918     }
2919 
2920     {
2921 	char *cmd = bmake_strdup(p);
2922 	GNodeListNode *ln;
2923 
2924 	for (ln = targets->first; ln != NULL; ln = ln->next) {
2925 	    GNode *gn = ln->datum;
2926 	    ParseAddCmd(gn, cmd);
2927 	}
2928 #ifdef CLEANUP
2929 	Lst_Append(targCmds, cmd);
2930 #endif
2931     }
2932 }
2933 
2934 static Boolean
2935 ParseDirective(char *line)
2936 {
2937     char *cp;
2938 
2939     if (*line == '.') {
2940 	/*
2941 	 * Lines that begin with the special character may be
2942 	 * include or undef directives.
2943 	 * On the other hand they can be suffix rules (.c.o: ...)
2944 	 * or just dependencies for filenames that start '.'.
2945 	 */
2946 	cp = line + 1;
2947 	pp_skip_whitespace(&cp);
2948 	if (IsInclude(cp, FALSE)) {
2949 	    ParseDoInclude(cp);
2950 	    return TRUE;
2951 	}
2952 	if (strncmp(cp, "undef", 5) == 0) {
2953 	    const char *varname;
2954 	    cp += 5;
2955 	    pp_skip_whitespace(&cp);
2956 	    varname = cp;
2957 	    for (; !ch_isspace(*cp) && *cp != '\0'; cp++)
2958 		continue;
2959 	    *cp = '\0';
2960 	    Var_Delete(varname, VAR_GLOBAL);
2961 	    /* TODO: undefine all variables, not only the first */
2962 	    /* TODO: use Str_Words, like everywhere else */
2963 	    return TRUE;
2964 	} else if (strncmp(cp, "export", 6) == 0) {
2965 	    cp += 6;
2966 	    pp_skip_whitespace(&cp);
2967 	    Var_Export(cp, TRUE);
2968 	    return TRUE;
2969 	} else if (strncmp(cp, "unexport", 8) == 0) {
2970 	    Var_UnExport(cp);
2971 	    return TRUE;
2972 	} else if (strncmp(cp, "info", 4) == 0 ||
2973 		   strncmp(cp, "error", 5) == 0 ||
2974 		   strncmp(cp, "warning", 7) == 0) {
2975 	    if (ParseMessage(cp))
2976 		return TRUE;
2977 	}
2978     }
2979     return FALSE;
2980 }
2981 
2982 static Boolean
2983 ParseVarassign(const char *line)
2984 {
2985     VarAssign var;
2986     if (Parse_IsVar(line, &var)) {
2987 	FinishDependencyGroup();
2988 	Parse_DoVar(&var, VAR_GLOBAL);
2989 	return TRUE;
2990     }
2991     return FALSE;
2992 }
2993 
2994 static char *
2995 FindSemicolon(char *p)
2996 {
2997     int level = 0;
2998 
2999     for (; *p != '\0'; p++) {
3000 	if (*p == '\\' && p[1] != '\0') {
3001 	    p++;
3002 	    continue;
3003 	}
3004 
3005 	if (*p == '$' && (p[1] == '(' || p[1] == '{')) {
3006 	    level++;
3007 	    continue;
3008 	}
3009 
3010 	if (level > 0 && (*p == ')' || *p == '}')) {
3011 	    level--;
3012 	    continue;
3013 	}
3014 
3015 	if (level == 0 && *p == ';') {
3016 	    break;
3017 	}
3018     }
3019     return p;
3020 }
3021 
3022 /* dependency	-> target... op [source...]
3023  * op		-> ':' | '::' | '!' */
3024 static void
3025 ParseDependency(char *line)
3026 {
3027     VarEvalFlags eflags;
3028     char *expanded_line;
3029     const char *shellcmd = NULL;
3030 
3031     /*
3032      * For some reason - probably to make the parser impossible -
3033      * a ';' can be used to separate commands from dependencies.
3034      * Attempt to avoid ';' inside substitution patterns.
3035      */
3036     {
3037 	char *semicolon = FindSemicolon(line);
3038 	if (*semicolon != '\0') {
3039 	    /* Terminate the dependency list at the ';' */
3040 	    *semicolon = '\0';
3041 	    shellcmd = semicolon + 1;
3042 	}
3043     }
3044 
3045     /*
3046      * We now know it's a dependency line so it needs to have all
3047      * variables expanded before being parsed.
3048      *
3049      * XXX: Ideally the dependency line would first be split into
3050      * its left-hand side, dependency operator and right-hand side,
3051      * and then each side would be expanded on its own.  This would
3052      * allow for the left-hand side to allow only defined variables
3053      * and to allow variables on the right-hand side to be undefined
3054      * as well.
3055      *
3056      * Parsing the line first would also prevent that targets
3057      * generated from variable expressions are interpreted as the
3058      * dependency operator, such as in "target${:U:} middle: source",
3059      * in which the middle is interpreted as a source, not a target.
3060      */
3061 
3062     /* In lint mode, allow undefined variables to appear in
3063      * dependency lines.
3064      *
3065      * Ideally, only the right-hand side would allow undefined
3066      * variables since it is common to have no dependencies.
3067      * Having undefined variables on the left-hand side is more
3068      * unusual though.  Since both sides are expanded in a single
3069      * pass, there is not much choice what to do here.
3070      *
3071      * In normal mode, it does not matter whether undefined
3072      * variables are allowed or not since as of 2020-09-14,
3073      * Var_Parse does not print any parse errors in such a case.
3074      * It simply returns the special empty string var_Error,
3075      * which cannot be detected in the result of Var_Subst. */
3076     eflags = DEBUG(LINT) ? VARE_WANTRES : VARE_UNDEFERR | VARE_WANTRES;
3077     (void)Var_Subst(line, VAR_CMDLINE, eflags, &expanded_line);
3078     /* TODO: handle errors */
3079 
3080     /* Need a fresh list for the target nodes */
3081     if (targets != NULL)
3082 	Lst_Free(targets);
3083     targets = Lst_New();
3084 
3085     ParseDoDependency(expanded_line);
3086     free(expanded_line);
3087 
3088     if (shellcmd != NULL)
3089 	ParseLine_ShellCommand(shellcmd);
3090 }
3091 
3092 static void
3093 ParseLine(char *line)
3094 {
3095     if (ParseDirective(line))
3096 	return;
3097 
3098     if (*line == '\t') {
3099 	ParseLine_ShellCommand(line + 1);
3100 	return;
3101     }
3102 
3103 #ifdef SYSVINCLUDE
3104     if (IsSysVInclude(line)) {
3105 	/*
3106 	 * It's an S3/S5-style "include".
3107 	 */
3108 	ParseTraditionalInclude(line);
3109 	return;
3110     }
3111 #endif
3112 
3113 #ifdef GMAKEEXPORT
3114     if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
3115 	strchr(line, ':') == NULL) {
3116 	/*
3117 	 * It's a Gmake "export".
3118 	 */
3119 	ParseGmakeExport(line);
3120 	return;
3121     }
3122 #endif
3123 
3124     if (ParseVarassign(line))
3125 	return;
3126 
3127     FinishDependencyGroup();
3128 
3129     ParseDependency(line);
3130 }
3131 
3132 /* Parse a top-level makefile into its component parts, incorporating them
3133  * into the global dependency graph.
3134  *
3135  * Input:
3136  *	name		The name of the file being read
3137  *	fd		The open file to parse; will be closed at the end
3138  */
3139 void
3140 Parse_File(const char *name, int fd)
3141 {
3142     char *line;			/* the line we're working on */
3143     struct loadedfile *lf;
3144 
3145     lf = loadfile(name, fd);
3146 
3147     assert(targets == NULL);
3148     fatals = 0;
3149 
3150     if (name == NULL)
3151 	name = "(stdin)";
3152 
3153     Parse_SetInput(name, 0, -1, loadedfile_nextbuf, lf);
3154     CurFile()->lf = lf;
3155 
3156     do {
3157 	while ((line = ParseReadLine()) != NULL) {
3158 	    DEBUG2(PARSE, "ParseReadLine (%d): '%s'\n",
3159 		   CurFile()->lineno, line);
3160 	    ParseLine(line);
3161 	}
3162 	/*
3163 	 * Reached EOF, but it may be just EOF of an include file...
3164 	 */
3165     } while (ParseEOF());
3166 
3167     FinishDependencyGroup();
3168 
3169     if (fatals) {
3170 	(void)fflush(stdout);
3171 	(void)fprintf(stderr,
3172 		      "%s: Fatal errors encountered -- cannot continue",
3173 		      progname);
3174 	PrintOnError(NULL, NULL);
3175 	exit(1);
3176     }
3177 }
3178 
3179 /* Initialize the parsing module. */
3180 void
3181 Parse_Init(void)
3182 {
3183     mainNode = NULL;
3184     parseIncPath = Lst_New();
3185     sysIncPath = Lst_New();
3186     defSysIncPath = Lst_New();
3187     Vector_Init(&includes, sizeof(IFile));
3188 #ifdef CLEANUP
3189     targCmds = Lst_New();
3190 #endif
3191 }
3192 
3193 /* Clean up the parsing module. */
3194 void
3195 Parse_End(void)
3196 {
3197 #ifdef CLEANUP
3198     Lst_Destroy(targCmds, free);
3199     assert(targets == NULL);
3200     Lst_Destroy(defSysIncPath, Dir_Destroy);
3201     Lst_Destroy(sysIncPath, Dir_Destroy);
3202     Lst_Destroy(parseIncPath, Dir_Destroy);
3203     assert(includes.len == 0);
3204     Vector_Done(&includes);
3205 #endif
3206 }
3207 
3208 
3209 /*-
3210  *-----------------------------------------------------------------------
3211  * Parse_MainName --
3212  *	Return a Lst of the main target to create for main()'s sake. If
3213  *	no such target exists, we Punt with an obnoxious error message.
3214  *
3215  * Results:
3216  *	A Lst of the single node to create.
3217  *
3218  * Side Effects:
3219  *	None.
3220  *
3221  *-----------------------------------------------------------------------
3222  */
3223 GNodeList *
3224 Parse_MainName(void)
3225 {
3226     GNodeList *mainList;
3227 
3228     mainList = Lst_New();
3229 
3230     if (mainNode == NULL) {
3231 	Punt("no target to make.");
3232 	/*NOTREACHED*/
3233     } else if (mainNode->type & OP_DOUBLEDEP) {
3234 	Lst_Append(mainList, mainNode);
3235 	Lst_AppendAll(mainList, mainNode->cohorts);
3236     } else
3237 	Lst_Append(mainList, mainNode);
3238     Var_Append(".TARGETS", mainNode->name, VAR_GLOBAL);
3239     return mainList;
3240 }
3241 
3242 int
3243 Parse_GetFatals(void)
3244 {
3245     return fatals;
3246 }
3247