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parse.c revision 1.362
      1 /*	$NetBSD: parse.c,v 1.362 2020/10/04 21:53:28 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  * parse.c --
     73  *	Functions to parse a makefile.
     74  *
     75  *	One function, Parse_Init, must be called before any functions
     76  *	in this module are used. After that, the function Parse_File is the
     77  *	main entry point and controls most of the other functions in this
     78  *	module.
     79  *
     80  *	Most important structures are kept in Lsts. Directories for
     81  *	the .include "..." function are kept in the 'parseIncPath' Lst, while
     82  *	those for the .include <...> are kept in the 'sysIncPath' Lst. The
     83  *	targets currently being defined are kept in the 'targets' Lst.
     84  *
     85  *	The variables 'fname' and 'lineno' are used to track the name
     86  *	of the current file and the line number in that file so that error
     87  *	messages can be more meaningful.
     88  *
     89  * Interface:
     90  *	Parse_Init	Initialization function which must be
     91  *			called before anything else in this module
     92  *			is used.
     93  *
     94  *	Parse_End	Cleanup the module
     95  *
     96  *	Parse_File	Function used to parse a makefile. It must
     97  *			be given the name of the file, which should
     98  *			already have been opened, and a function
     99  *			to call to read a character from the file.
    100  *
    101  *	Parse_IsVar	Returns TRUE if the given line is a
    102  *			variable assignment. Used by MainParseArgs
    103  *			to determine if an argument is a target
    104  *			or a variable assignment. Used internally
    105  *			for pretty much the same thing...
    106  *
    107  *	Parse_Error	Function called when an error occurs in
    108  *			parsing. Used by the variable and
    109  *			conditional modules.
    110  *
    111  *	Parse_MainName	Returns a Lst of the main target to create.
    112  */
    113 
    114 #include <sys/types.h>
    115 #include <sys/mman.h>
    116 #include <sys/stat.h>
    117 #include <errno.h>
    118 #include <stdarg.h>
    119 #include <stdint.h>
    120 
    121 #ifndef MAP_FILE
    122 #define MAP_FILE 0
    123 #endif
    124 #ifndef MAP_COPY
    125 #define MAP_COPY MAP_PRIVATE
    126 #endif
    127 
    128 #include "make.h"
    129 #include "dir.h"
    130 #include "job.h"
    131 #include "pathnames.h"
    132 
    133 /*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
    134 MAKE_RCSID("$NetBSD: parse.c,v 1.362 2020/10/04 21:53:28 rillig Exp $");
    135 
    136 /* types and constants */
    137 
    138 /*
    139  * Structure for a file being read ("included file")
    140  */
    141 typedef struct IFile {
    142     char *fname;		/* name of file */
    143     Boolean fromForLoop;	/* simulated .include by the .for loop */
    144     int lineno;			/* current line number in file */
    145     int first_lineno;		/* line number of start of text */
    146     int cond_depth;		/* 'if' nesting when file opened */
    147     Boolean depending;		/* state of doing_depend on EOF */
    148     char *P_str;		/* point to base of string buffer */
    149     char *P_ptr;		/* point to next char of string buffer */
    150     char *P_end;		/* point to the end of string buffer */
    151     char *(*nextbuf)(void *, size_t *); /* Function to get more data */
    152     void *nextbuf_arg;		/* Opaque arg for nextbuf() */
    153     struct loadedfile *lf;	/* loadedfile object, if any */
    154 } IFile;
    155 
    156 
    157 /*
    158  * These values are returned by ParseEOF to tell Parse_File whether to
    159  * CONTINUE parsing, i.e. it had only reached the end of an include file,
    160  * or if it's DONE.
    161  */
    162 #define CONTINUE	1
    163 #define DONE		0
    164 
    165 /*
    166  * Tokens for target attributes
    167  */
    168 typedef enum {
    169     Begin,		/* .BEGIN */
    170     Default,		/* .DEFAULT */
    171     DeleteOnError,	/* .DELETE_ON_ERROR */
    172     End,		/* .END */
    173     dotError,		/* .ERROR */
    174     Ignore,		/* .IGNORE */
    175     Includes,		/* .INCLUDES */
    176     Interrupt,		/* .INTERRUPT */
    177     Libs,		/* .LIBS */
    178     Meta,		/* .META */
    179     MFlags,		/* .MFLAGS or .MAKEFLAGS */
    180     Main,		/* .MAIN and we don't have anything user-specified to
    181 			 * make */
    182     NoExport,		/* .NOEXPORT */
    183     NoMeta,		/* .NOMETA */
    184     NoMetaCmp,		/* .NOMETA_CMP */
    185     NoPath,		/* .NOPATH */
    186     Not,		/* Not special */
    187     NotParallel,	/* .NOTPARALLEL */
    188     Null,		/* .NULL */
    189     ExObjdir,		/* .OBJDIR */
    190     Order,		/* .ORDER */
    191     Parallel,		/* .PARALLEL */
    192     ExPath,		/* .PATH */
    193     Phony,		/* .PHONY */
    194 #ifdef POSIX
    195     Posix,		/* .POSIX */
    196 #endif
    197     Precious,		/* .PRECIOUS */
    198     ExShell,		/* .SHELL */
    199     Silent,		/* .SILENT */
    200     SingleShell,	/* .SINGLESHELL */
    201     Stale,		/* .STALE */
    202     Suffixes,		/* .SUFFIXES */
    203     Wait,		/* .WAIT */
    204     Attribute		/* Generic attribute */
    205 } ParseSpecial;
    206 
    207 /* result data */
    208 
    209 /*
    210  * The main target to create. This is the first target on the first
    211  * dependency line in the first makefile.
    212  */
    213 static GNode *mainNode;
    214 
    215 /* eval state */
    216 
    217 /* During parsing, the targets from the currently active dependency line,
    218  * or NULL if the current line does not belong to a dependency line, for
    219  * example because it is a variable assignment.
    220  *
    221  * See unit-tests/deptgt.mk, keyword "parse.c:targets". */
    222 static GNodeList *targets;
    223 
    224 #ifdef CLEANUP
    225 /* command lines for targets */
    226 static StringList *targCmds;
    227 #endif
    228 
    229 /*
    230  * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
    231  * seen, then set to each successive source on the line.
    232  */
    233 static GNode	*predecessor;
    234 
    235 /* parser state */
    236 
    237 /* number of fatal errors */
    238 static int fatals = 0;
    239 
    240 /*
    241  * Variables for doing includes
    242  */
    243 
    244 /* current file being read */
    245 static IFile *curFile;
    246 
    247 /* The include chain of makefiles that leads to curFile.  At the bottom of
    248  * the stack is the top-level makefile from the command line, and on top of
    249  * this file, there are the included files or .for loops, up to but excluding
    250  * curFile.
    251  *
    252  * This data could be used to print stack traces on parse errors.  As of
    253  * 2020-09-14, this is not done though.  It seems quite simple to print the
    254  * tuples (fname:lineno:fromForLoop), from top to bottom.  This simple idea is
    255  * made complicated by the fact that the .for loops also use this stack for
    256  * storing information.
    257  *
    258  * The lineno fields of the IFiles with fromForLoop == TRUE look confusing,
    259  * which is demonstrated by the test 'include-main.mk'.  They seem sorted
    260  * backwards since they tell the number of completely parsed lines, which for
    261  * a .for loop is right after the terminating .endfor.  To compensate for this
    262  * confusion, there is another field first_lineno pointing at the start of the
    263  * .for loop, 1-based for human consumption.
    264  *
    265  * To make the stack trace intuitive, the entry below the first .for loop must
    266  * be ignored completely since neither its lineno nor its first_lineno is
    267  * useful.  Instead, the topmost .for loop needs to be printed twice, once
    268  * with its first_lineno and once with its lineno.
    269  *
    270  * As of 2020-09-15, using the above rules, the stack trace for the .info line
    271  * in include-subsub.mk would be:
    272  *
    273  *	curFile:	include-subsub.mk:4
    274  *			(lineno, from an .include)
    275  *	includes[4]:	include-sub.mk:32
    276  *			(lineno, from a .for loop below an .include)
    277  *	includes[4]:	include-sub.mk:31
    278  *			(first_lineno, from a .for loop, lineno == 32)
    279  *	includes[3]:	include-sub.mk:30
    280  *			(first_lineno, from a .for loop, lineno == 33)
    281  *	includes[2]:	include-sub.mk:29
    282  *			(first_lineno, from a .for loop, lineno == 34)
    283  *	includes[1]:	include-sub.mk:35
    284  *			(not printed since it is below a .for loop)
    285  *	includes[0]:	include-main.mk:27
    286  */
    287 static Stack /* of *IFile */ includes;
    288 
    289 /* include paths (lists of directories) */
    290 SearchPath *parseIncPath;	/* dirs for "..." includes */
    291 SearchPath *sysIncPath;		/* dirs for <...> includes */
    292 SearchPath *defIncPath;		/* default for sysIncPath */
    293 
    294 /* parser tables */
    295 
    296 /*
    297  * The parseKeywords table is searched using binary search when deciding
    298  * if a target or source is special. The 'spec' field is the ParseSpecial
    299  * type of the keyword ("Not" if the keyword isn't special as a target) while
    300  * the 'op' field is the operator to apply to the list of targets if the
    301  * keyword is used as a source ("0" if the keyword isn't special as a source)
    302  */
    303 static const struct {
    304     const char   *name;		/* Name of keyword */
    305     ParseSpecial  spec;		/* Type when used as a target */
    306     GNodeType	  op;		/* Operator when used as a source */
    307 } parseKeywords[] = {
    308     { ".BEGIN",		Begin,		0 },
    309     { ".DEFAULT",	Default,	0 },
    310     { ".DELETE_ON_ERROR", DeleteOnError, 0 },
    311     { ".END",		End,		0 },
    312     { ".ERROR",		dotError,	0 },
    313     { ".EXEC",		Attribute,	OP_EXEC },
    314     { ".IGNORE",	Ignore,		OP_IGNORE },
    315     { ".INCLUDES",	Includes,	0 },
    316     { ".INTERRUPT",	Interrupt,	0 },
    317     { ".INVISIBLE",	Attribute,	OP_INVISIBLE },
    318     { ".JOIN",		Attribute,	OP_JOIN },
    319     { ".LIBS",		Libs,		0 },
    320     { ".MADE",		Attribute,	OP_MADE },
    321     { ".MAIN",		Main,		0 },
    322     { ".MAKE",		Attribute,	OP_MAKE },
    323     { ".MAKEFLAGS",	MFlags,		0 },
    324     { ".META",		Meta,		OP_META },
    325     { ".MFLAGS",	MFlags,		0 },
    326     { ".NOMETA",	NoMeta,		OP_NOMETA },
    327     { ".NOMETA_CMP",	NoMetaCmp,	OP_NOMETA_CMP },
    328     { ".NOPATH",	NoPath,		OP_NOPATH },
    329     { ".NOTMAIN",	Attribute,	OP_NOTMAIN },
    330     { ".NOTPARALLEL",	NotParallel,	0 },
    331     { ".NO_PARALLEL",	NotParallel,	0 },
    332     { ".NULL",		Null,		0 },
    333     { ".OBJDIR",	ExObjdir,	0 },
    334     { ".OPTIONAL",	Attribute,	OP_OPTIONAL },
    335     { ".ORDER",		Order,		0 },
    336     { ".PARALLEL",	Parallel,	0 },
    337     { ".PATH",		ExPath,		0 },
    338     { ".PHONY",		Phony,		OP_PHONY },
    339 #ifdef POSIX
    340     { ".POSIX",		Posix,		0 },
    341 #endif
    342     { ".PRECIOUS",	Precious,	OP_PRECIOUS },
    343     { ".RECURSIVE",	Attribute,	OP_MAKE },
    344     { ".SHELL",		ExShell,	0 },
    345     { ".SILENT",	Silent,		OP_SILENT },
    346     { ".SINGLESHELL",	SingleShell,	0 },
    347     { ".STALE",		Stale,		0 },
    348     { ".SUFFIXES",	Suffixes,	0 },
    349     { ".USE",		Attribute,	OP_USE },
    350     { ".USEBEFORE",	Attribute,	OP_USEBEFORE },
    351     { ".WAIT",		Wait,		0 },
    352 };
    353 
    354 /* file loader */
    355 
    356 struct loadedfile {
    357 	const char *path;		/* name, for error reports */
    358 	char *buf;			/* contents buffer */
    359 	size_t len;			/* length of contents */
    360 	size_t maplen;			/* length of mmap area, or 0 */
    361 	Boolean used;			/* XXX: have we used the data yet */
    362 };
    363 
    364 static struct loadedfile *
    365 loadedfile_create(const char *path)
    366 {
    367 	struct loadedfile *lf;
    368 
    369 	lf = bmake_malloc(sizeof(*lf));
    370 	lf->path = path == NULL ? "(stdin)" : path;
    371 	lf->buf = NULL;
    372 	lf->len = 0;
    373 	lf->maplen = 0;
    374 	lf->used = FALSE;
    375 	return lf;
    376 }
    377 
    378 static void
    379 loadedfile_destroy(struct loadedfile *lf)
    380 {
    381 	if (lf->buf != NULL) {
    382 		if (lf->maplen > 0) {
    383 			munmap(lf->buf, lf->maplen);
    384 		} else {
    385 			free(lf->buf);
    386 		}
    387 	}
    388 	free(lf);
    389 }
    390 
    391 /*
    392  * nextbuf() operation for loadedfile, as needed by the weird and twisted
    393  * logic below. Once that's cleaned up, we can get rid of lf->used...
    394  */
    395 static char *
    396 loadedfile_nextbuf(void *x, size_t *len)
    397 {
    398 	struct loadedfile *lf = x;
    399 
    400 	if (lf->used) {
    401 		return NULL;
    402 	}
    403 	lf->used = TRUE;
    404 	*len = lf->len;
    405 	return lf->buf;
    406 }
    407 
    408 /*
    409  * Try to get the size of a file.
    410  */
    411 static Boolean
    412 load_getsize(int fd, size_t *ret)
    413 {
    414 	struct stat st;
    415 
    416 	if (fstat(fd, &st) < 0) {
    417 		return FALSE;
    418 	}
    419 
    420 	if (!S_ISREG(st.st_mode)) {
    421 		return FALSE;
    422 	}
    423 
    424 	/*
    425 	 * st_size is an off_t, which is 64 bits signed; *ret is
    426 	 * size_t, which might be 32 bits unsigned or 64 bits
    427 	 * unsigned. Rather than being elaborate, just punt on
    428 	 * files that are more than 2^31 bytes. We should never
    429 	 * see a makefile that size in practice...
    430 	 *
    431 	 * While we're at it reject negative sizes too, just in case.
    432 	 */
    433 	if (st.st_size < 0 || st.st_size > 0x7fffffff) {
    434 		return FALSE;
    435 	}
    436 
    437 	*ret = (size_t) st.st_size;
    438 	return TRUE;
    439 }
    440 
    441 /*
    442  * Read in a file.
    443  *
    444  * Until the path search logic can be moved under here instead of
    445  * being in the caller in another source file, we need to have the fd
    446  * passed in already open. Bleh.
    447  *
    448  * If the path is NULL use stdin and (to insure against fd leaks)
    449  * assert that the caller passed in -1.
    450  */
    451 static struct loadedfile *
    452 loadfile(const char *path, int fd)
    453 {
    454 	struct loadedfile *lf;
    455 	static long pagesize = 0;
    456 	ssize_t result;
    457 	size_t bufpos;
    458 
    459 	lf = loadedfile_create(path);
    460 
    461 	if (path == NULL) {
    462 		assert(fd == -1);
    463 		fd = STDIN_FILENO;
    464 	} else {
    465 #if 0 /* notyet */
    466 		fd = open(path, O_RDONLY);
    467 		if (fd < 0) {
    468 			...
    469 			Error("%s: %s", path, strerror(errno));
    470 			exit(1);
    471 		}
    472 #endif
    473 	}
    474 
    475 	if (load_getsize(fd, &lf->len)) {
    476 		/* found a size, try mmap */
    477 		if (pagesize == 0)
    478 			pagesize = sysconf(_SC_PAGESIZE);
    479 		if (pagesize <= 0) {
    480 			pagesize = 0x1000;
    481 		}
    482 		/* round size up to a page */
    483 		lf->maplen = pagesize * ((lf->len + pagesize - 1)/pagesize);
    484 
    485 		/*
    486 		 * XXX hack for dealing with empty files; remove when
    487 		 * we're no longer limited by interfacing to the old
    488 		 * logic elsewhere in this file.
    489 		 */
    490 		if (lf->maplen == 0) {
    491 			lf->maplen = pagesize;
    492 		}
    493 
    494 		/*
    495 		 * FUTURE: remove PROT_WRITE when the parser no longer
    496 		 * needs to scribble on the input.
    497 		 */
    498 		lf->buf = mmap(NULL, lf->maplen, PROT_READ|PROT_WRITE,
    499 			       MAP_FILE|MAP_COPY, fd, 0);
    500 		if (lf->buf != MAP_FAILED) {
    501 			/* succeeded */
    502 			if (lf->len == lf->maplen && lf->buf[lf->len - 1] != '\n') {
    503 				char *b = bmake_malloc(lf->len + 1);
    504 				b[lf->len] = '\n';
    505 				memcpy(b, lf->buf, lf->len++);
    506 				munmap(lf->buf, lf->maplen);
    507 				lf->maplen = 0;
    508 				lf->buf = b;
    509 			}
    510 			goto done;
    511 		}
    512 	}
    513 
    514 	/* cannot mmap; load the traditional way */
    515 
    516 	lf->maplen = 0;
    517 	lf->len = 1024;
    518 	lf->buf = bmake_malloc(lf->len);
    519 
    520 	bufpos = 0;
    521 	while (1) {
    522 		assert(bufpos <= lf->len);
    523 		if (bufpos == lf->len) {
    524 			if (lf->len > SIZE_MAX/2) {
    525 				errno = EFBIG;
    526 				Error("%s: file too large", path);
    527 				exit(1);
    528 			}
    529 			lf->len *= 2;
    530 			lf->buf = bmake_realloc(lf->buf, lf->len);
    531 		}
    532 		assert(bufpos < lf->len);
    533 		result = read(fd, lf->buf + bufpos, lf->len - bufpos);
    534 		if (result < 0) {
    535 			Error("%s: read error: %s", path, strerror(errno));
    536 			exit(1);
    537 		}
    538 		if (result == 0) {
    539 			break;
    540 		}
    541 		bufpos += result;
    542 	}
    543 	assert(bufpos <= lf->len);
    544 	lf->len = bufpos;
    545 
    546 	/* truncate malloc region to actual length (maybe not useful) */
    547 	if (lf->len > 0) {
    548 		/* as for mmap case, ensure trailing \n */
    549 		if (lf->buf[lf->len - 1] != '\n')
    550 			lf->len++;
    551 		lf->buf = bmake_realloc(lf->buf, lf->len);
    552 		lf->buf[lf->len - 1] = '\n';
    553 	}
    554 
    555 done:
    556 	if (path != NULL) {
    557 		close(fd);
    558 	}
    559 	return lf;
    560 }
    561 
    562 /* old code */
    563 
    564 /* Check if the current character is escaped on the current line. */
    565 static Boolean
    566 ParseIsEscaped(const char *line, const char *c)
    567 {
    568     Boolean active = FALSE;
    569     for (;;) {
    570 	if (line == c)
    571 	    return active;
    572 	if (*--c != '\\')
    573 	    return active;
    574 	active = !active;
    575     }
    576 }
    577 
    578 /* Add the filename and lineno to the GNode so that we remember where it
    579  * was first defined. */
    580 static void
    581 ParseMark(GNode *gn)
    582 {
    583     gn->fname = curFile->fname;
    584     gn->lineno = curFile->lineno;
    585 }
    586 
    587 /*-
    588  *----------------------------------------------------------------------
    589  * ParseFindKeyword --
    590  *	Look in the table of keywords for one matching the given string.
    591  *
    592  * Input:
    593  *	str		String to find
    594  *
    595  * Results:
    596  *	The index of the keyword, or -1 if it isn't there.
    597  *
    598  * Side Effects:
    599  *	None
    600  *----------------------------------------------------------------------
    601  */
    602 static int
    603 ParseFindKeyword(const char *str)
    604 {
    605     int    start, end, cur;
    606     int    diff;
    607 
    608     start = 0;
    609     end = (sizeof(parseKeywords)/sizeof(parseKeywords[0])) - 1;
    610 
    611     do {
    612 	cur = start + ((end - start) / 2);
    613 	diff = strcmp(str, parseKeywords[cur].name);
    614 
    615 	if (diff == 0) {
    616 	    return cur;
    617 	} else if (diff < 0) {
    618 	    end = cur - 1;
    619 	} else {
    620 	    start = cur + 1;
    621 	}
    622     } while (start <= end);
    623     return -1;
    624 }
    625 
    626 static void
    627 PrintLocation(FILE *f, const char *filename, size_t lineno)
    628 {
    629 	char dirbuf[MAXPATHLEN+1];
    630 	const char *dir, *base;
    631 	char *dir_freeIt, *base_freeIt;
    632 
    633 	if (*filename == '/' || strcmp(filename, "(stdin)") == 0) {
    634 		(void)fprintf(f, "\"%s\" line %zu: ", filename, lineno);
    635 		return;
    636 	}
    637 
    638 	/* Find out which makefile is the culprit.
    639 	 * We try ${.PARSEDIR} and apply realpath(3) if not absolute. */
    640 
    641 	dir = Var_Value(".PARSEDIR", VAR_GLOBAL, &dir_freeIt);
    642 	if (dir == NULL)
    643 		dir = ".";
    644 	if (*dir != '/')
    645 		dir = realpath(dir, dirbuf);
    646 
    647 	base = Var_Value(".PARSEFILE", VAR_GLOBAL, &base_freeIt);
    648 	if (base == NULL) {
    649 		const char *slash = strrchr(filename, '/');
    650 		base = slash != NULL ? slash + 1 : filename;
    651 	}
    652 
    653 	(void)fprintf(f, "\"%s/%s\" line %zu: ", dir, base, lineno);
    654 	bmake_free(base_freeIt);
    655 	bmake_free(dir_freeIt);
    656 }
    657 
    658 /* Print a parse error message, including location information.
    659  *
    660  * Increment "fatals" if the level is PARSE_FATAL, and continue parsing
    661  * until the end of the current top-level makefile, then exit (see
    662  * Parse_File).
    663  */
    664 static void
    665 ParseVErrorInternal(FILE *f, const char *cfname, size_t clineno, int type,
    666     const char *fmt, va_list ap)
    667 {
    668 	static Boolean fatal_warning_error_printed = FALSE;
    669 
    670 	(void)fprintf(f, "%s: ", progname);
    671 
    672 	if (cfname != NULL)
    673 		PrintLocation(f, cfname, clineno);
    674 	if (type == PARSE_WARNING)
    675 		(void)fprintf(f, "warning: ");
    676 	(void)vfprintf(f, fmt, ap);
    677 	(void)fprintf(f, "\n");
    678 	(void)fflush(f);
    679 
    680 	if (type == PARSE_INFO)
    681 		return;
    682 	if (type == PARSE_FATAL || parseWarnFatal)
    683 		fatals++;
    684 	if (parseWarnFatal && !fatal_warning_error_printed) {
    685 		Error("parsing warnings being treated as errors");
    686 		fatal_warning_error_printed = TRUE;
    687 	}
    688 }
    689 
    690 static void
    691 ParseErrorInternal(const char *cfname, size_t clineno, int type,
    692     const char *fmt, ...)
    693 {
    694 	va_list ap;
    695 
    696 	va_start(ap, fmt);
    697 	(void)fflush(stdout);
    698 	ParseVErrorInternal(stderr, cfname, clineno, type, fmt, ap);
    699 	va_end(ap);
    700 
    701 	if (debug_file != stderr && debug_file != stdout) {
    702 		va_start(ap, fmt);
    703 		ParseVErrorInternal(debug_file, cfname, clineno, type, fmt, ap);
    704 		va_end(ap);
    705 	}
    706 }
    707 
    708 /* External interface to ParseErrorInternal; uses the default filename and
    709  * line number.
    710  *
    711  * Fmt is given without a trailing newline. */
    712 void
    713 Parse_Error(int type, const char *fmt, ...)
    714 {
    715 	va_list ap;
    716 	const char *fname;
    717 	size_t lineno;
    718 
    719 	if (curFile == NULL) {
    720 		fname = NULL;
    721 		lineno = 0;
    722 	} else {
    723 		fname = curFile->fname;
    724 		lineno = curFile->lineno;
    725 	}
    726 
    727 	va_start(ap, fmt);
    728 	(void)fflush(stdout);
    729 	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
    730 	va_end(ap);
    731 
    732 	if (debug_file != stderr && debug_file != stdout) {
    733 		va_start(ap, fmt);
    734 		ParseVErrorInternal(debug_file, fname, lineno, type, fmt, ap);
    735 		va_end(ap);
    736 	}
    737 }
    738 
    739 
    740 /* Parse a .info .warning or .error directive.
    741  *
    742  * The input is the line minus the ".".  We substitute variables, print the
    743  * message and exit(1) (for .error) or just print a warning if the directive
    744  * is malformed.
    745  */
    746 static Boolean
    747 ParseMessage(char *line)
    748 {
    749     int mtype;
    750 
    751     switch(*line) {
    752     case 'i':
    753 	mtype = PARSE_INFO;
    754 	break;
    755     case 'w':
    756 	mtype = PARSE_WARNING;
    757 	break;
    758     case 'e':
    759 	mtype = PARSE_FATAL;
    760 	break;
    761     default:
    762 	Parse_Error(PARSE_WARNING, "invalid syntax: \".%s\"", line);
    763 	return FALSE;
    764     }
    765 
    766     while (ch_isalpha(*line))
    767 	line++;
    768     if (!ch_isspace(*line))
    769 	return FALSE;			/* not for us */
    770     pp_skip_whitespace(&line);
    771 
    772     (void)Var_Subst(line, VAR_CMD, VARE_WANTRES, &line);
    773     /* TODO: handle errors */
    774     Parse_Error(mtype, "%s", line);
    775     free(line);
    776 
    777     if (mtype == PARSE_FATAL) {
    778 	/* Terminate almost immediately. */
    779 	PrintOnError(NULL, NULL);
    780 	exit(1);
    781     }
    782     return TRUE;
    783 }
    784 
    785 struct ParseLinkSrcArgs {
    786     GNode *cgn;
    787 
    788     /* The special target of the current dependency line. */
    789     /* Example: for ".END: action", it is 'End'. */
    790     ParseSpecial specType;
    791 };
    792 
    793 /* Add the child to the parent's children.
    794  *
    795  * Add the parent to the child's parents, but only if the target is not
    796  * special.  An example for such a special target is .END, which does not
    797  * need to be informed once the child target has been made. */
    798 static void
    799 ParseLinkSrc(void *pgnp, void *data)
    800 {
    801     const struct ParseLinkSrcArgs *args = data;
    802     GNode *pgn = pgnp;
    803     GNode *cgn = args->cgn;
    804 
    805     if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(pgn->cohorts))
    806 	pgn = LstNode_Datum(Lst_Last(pgn->cohorts));
    807 
    808     Lst_Append(pgn->children, cgn);
    809     pgn->unmade++;
    810 
    811     if (args->specType == Not)
    812 	Lst_Append(cgn->parents, pgn);
    813 
    814     if (DEBUG(PARSE)) {
    815 	debug_printf("# %s: added child %s - %s\n",
    816 		     __func__, pgn->name, cgn->name);
    817 	Targ_PrintNode(pgn, 0);
    818 	Targ_PrintNode(cgn, 0);
    819     }
    820 }
    821 
    822 static Boolean
    823 TryApplyDependencyOperator(GNode *gn, GNodeType op)
    824 {
    825     /*
    826      * If the dependency mask of the operator and the node don't match and
    827      * the node has actually had an operator applied to it before, and
    828      * the operator actually has some dependency information in it, complain.
    829      */
    830     if (((op & OP_OPMASK) != (gn->type & OP_OPMASK)) &&
    831 	!OP_NOP(gn->type) && !OP_NOP(op))
    832     {
    833 	Parse_Error(PARSE_FATAL, "Inconsistent operator for %s", gn->name);
    834 	return FALSE;
    835     }
    836 
    837     if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
    838 	/*
    839 	 * If the node was the object of a :: operator, we need to create a
    840 	 * new instance of it for the children and commands on this dependency
    841 	 * line. The new instance is placed on the 'cohorts' list of the
    842 	 * initial one (note the initial one is not on its own cohorts list)
    843 	 * and the new instance is linked to all parents of the initial
    844 	 * instance.
    845 	 */
    846 	GNode	*cohort;
    847 
    848 	/*
    849 	 * Propagate copied bits to the initial node.  They'll be propagated
    850 	 * back to the rest of the cohorts later.
    851 	 */
    852 	gn->type |= op & ~OP_OPMASK;
    853 
    854 	cohort = Targ_NewInternalNode(gn->name);
    855 	if (doing_depend)
    856 	    ParseMark(cohort);
    857 	/*
    858 	 * Make the cohort invisible as well to avoid duplicating it into
    859 	 * other variables. True, parents of this target won't tend to do
    860 	 * anything with their local variables, but better safe than
    861 	 * sorry. (I think this is pointless now, since the relevant list
    862 	 * traversals will no longer see this node anyway. -mycroft)
    863 	 */
    864 	cohort->type = op | OP_INVISIBLE;
    865 	Lst_Append(gn->cohorts, cohort);
    866 	cohort->centurion = gn;
    867 	gn->unmade_cohorts++;
    868 	snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
    869 		gn->unmade_cohorts);
    870     } else {
    871 	/*
    872 	 * We don't want to nuke any previous flags (whatever they were) so we
    873 	 * just OR the new operator into the old
    874 	 */
    875 	gn->type |= op;
    876     }
    877 
    878     return TRUE;
    879 }
    880 
    881 static void
    882 ApplyDependencyOperator(GNodeType op)
    883 {
    884     GNodeListNode *ln;
    885     for (ln = targets->first; ln != NULL; ln = ln->next)
    886         if (!TryApplyDependencyOperator(ln->datum, op))
    887 	    break;
    888 }
    889 
    890 /*-
    891  *---------------------------------------------------------------------
    892  * ParseDoSrc  --
    893  *	Given the name of a source, figure out if it is an attribute
    894  *	and apply it to the targets if it is. Else decide if there is
    895  *	some attribute which should be applied *to* the source because
    896  *	of some special target and apply it if so. Otherwise, make the
    897  *	source be a child of the targets in the list 'targets'
    898  *
    899  * Input:
    900  *	tOp		operator (if any) from special targets
    901  *	src		name of the source to handle
    902  *
    903  * Results:
    904  *	None
    905  *
    906  * Side Effects:
    907  *	Operator bits may be added to the list of targets or to the source.
    908  *	The targets may have a new source added to their lists of children.
    909  *---------------------------------------------------------------------
    910  */
    911 static void
    912 ParseDoSrc(int tOp, const char *src, ParseSpecial specType)
    913 {
    914     GNode	*gn = NULL;
    915     static int wait_number = 0;
    916     char wait_src[16];
    917 
    918     if (*src == '.' && ch_isupper(src[1])) {
    919 	int keywd = ParseFindKeyword(src);
    920 	if (keywd != -1) {
    921 	    int op = parseKeywords[keywd].op;
    922 	    if (op != 0) {
    923 		ApplyDependencyOperator(op);
    924 		return;
    925 	    }
    926 	    if (parseKeywords[keywd].spec == Wait) {
    927 		/*
    928 		 * We add a .WAIT node in the dependency list.
    929 		 * After any dynamic dependencies (and filename globbing)
    930 		 * have happened, it is given a dependency on the each
    931 		 * previous child back to and previous .WAIT node.
    932 		 * The next child won't be scheduled until the .WAIT node
    933 		 * is built.
    934 		 * We give each .WAIT node a unique name (mainly for diag).
    935 		 */
    936 		snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
    937 		gn = Targ_NewInternalNode(wait_src);
    938 		if (doing_depend)
    939 		    ParseMark(gn);
    940 		gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
    941 		{
    942 		    struct ParseLinkSrcArgs args = { gn, specType };
    943 		    Lst_ForEach(targets, ParseLinkSrc, &args);
    944 		}
    945 		return;
    946 	    }
    947 	}
    948     }
    949 
    950     switch (specType) {
    951     case Main:
    952 	/*
    953 	 * If we have noted the existence of a .MAIN, it means we need
    954 	 * to add the sources of said target to the list of things
    955 	 * to create. The string 'src' is likely to be free, so we
    956 	 * must make a new copy of it. Note that this will only be
    957 	 * invoked if the user didn't specify a target on the command
    958 	 * line. This is to allow #ifmake's to succeed, or something...
    959 	 */
    960 	Lst_Append(create, bmake_strdup(src));
    961 	/*
    962 	 * Add the name to the .TARGETS variable as well, so the user can
    963 	 * employ that, if desired.
    964 	 */
    965 	Var_Append(".TARGETS", src, VAR_GLOBAL);
    966 	return;
    967 
    968     case Order:
    969 	/*
    970 	 * Create proper predecessor/successor links between the previous
    971 	 * source and the current one.
    972 	 */
    973 	gn = Targ_GetNode(src);
    974 	if (doing_depend)
    975 	    ParseMark(gn);
    976 	if (predecessor != NULL) {
    977 	    Lst_Append(predecessor->order_succ, gn);
    978 	    Lst_Append(gn->order_pred, predecessor);
    979 	    if (DEBUG(PARSE)) {
    980 		debug_printf("# %s: added Order dependency %s - %s\n",
    981 			     __func__, predecessor->name, gn->name);
    982 		Targ_PrintNode(predecessor, 0);
    983 		Targ_PrintNode(gn, 0);
    984 	    }
    985 	}
    986 	/*
    987 	 * The current source now becomes the predecessor for the next one.
    988 	 */
    989 	predecessor = gn;
    990 	break;
    991 
    992     default:
    993 	/*
    994 	 * If the source is not an attribute, we need to find/create
    995 	 * a node for it. After that we can apply any operator to it
    996 	 * from a special target or link it to its parents, as
    997 	 * appropriate.
    998 	 *
    999 	 * In the case of a source that was the object of a :: operator,
   1000 	 * the attribute is applied to all of its instances (as kept in
   1001 	 * the 'cohorts' list of the node) or all the cohorts are linked
   1002 	 * to all the targets.
   1003 	 */
   1004 
   1005 	/* Find/create the 'src' node and attach to all targets */
   1006 	gn = Targ_GetNode(src);
   1007 	if (doing_depend)
   1008 	    ParseMark(gn);
   1009 	if (tOp) {
   1010 	    gn->type |= tOp;
   1011 	} else {
   1012 	    {
   1013 	        struct ParseLinkSrcArgs args = { gn, specType };
   1014 		Lst_ForEach(targets, ParseLinkSrc, &args);
   1015 	    }
   1016 	}
   1017 	break;
   1018     }
   1019 }
   1020 
   1021 /* If we have yet to decide on a main target to make, in the absence of any
   1022  * user input, we want the first target on the first dependency line that is
   1023  * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made. */
   1024 static void
   1025 FindMainTarget(void)
   1026 {
   1027     GNodeListNode *ln;
   1028 
   1029     if (mainNode != NULL)
   1030         return;
   1031 
   1032     for (ln = targets->first; ln != NULL; ln = ln->next) {
   1033 	GNode *gn = ln->datum;
   1034 	if (!(gn->type & OP_NOTARGET)) {
   1035 	    mainNode = gn;
   1036 	    Targ_SetMain(gn);
   1037 	    return;
   1038 	}
   1039     }
   1040 }
   1041 
   1042 static void
   1043 ParseAddDir(void *path, void *name)
   1044 {
   1045     (void)Dir_AddDir(path, name);
   1046 }
   1047 
   1048 static void
   1049 ParseClearPath(void *path, void *unused MAKE_ATTR_UNUSED)
   1050 {
   1051     Dir_ClearPath(path);
   1052 }
   1053 
   1054 /*
   1055  * We got to the end of the line while we were still looking at targets.
   1056  *
   1057  * Ending a dependency line without an operator is a Bozo no-no.  As a
   1058  * heuristic, this is also often triggered by undetected conflicts from
   1059  * cvs/rcs merges.
   1060  */
   1061 static void
   1062 ParseErrorNoDependency(const char *lstart, const char *line)
   1063 {
   1064     if ((strncmp(line, "<<<<<<", 6) == 0) ||
   1065 	(strncmp(line, "======", 6) == 0) ||
   1066 	(strncmp(line, ">>>>>>", 6) == 0))
   1067 	Parse_Error(PARSE_FATAL,
   1068 		    "Makefile appears to contain unresolved cvs/rcs/??? merge conflicts");
   1069     else if (lstart[0] == '.') {
   1070 	const char *dirstart = lstart + 1;
   1071 	const char *dirend;
   1072 	cpp_skip_whitespace(&dirstart);
   1073 	dirend = dirstart;
   1074 	while (ch_isalnum(*dirend) || *dirend == '-')
   1075 	    dirend++;
   1076 	Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
   1077 		    (int)(dirend - dirstart), dirstart);
   1078     } else
   1079 	Parse_Error(PARSE_FATAL, "Need an operator");
   1080 }
   1081 
   1082 static void
   1083 ParseDependencyTargetWord(/*const*/ char **pp, const char *lstart)
   1084 {
   1085     /*const*/ char *cp = *pp;
   1086 
   1087     while (*cp != '\0') {
   1088 	if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' || *cp == '(') &&
   1089 	    !ParseIsEscaped(lstart, cp))
   1090 	    break;
   1091 
   1092 	if (*cp == '$') {
   1093 	    /*
   1094 	     * Must be a dynamic source (would have been expanded
   1095 	     * otherwise), so call the Var module to parse the puppy
   1096 	     * so we can safely advance beyond it...There should be
   1097 	     * no errors in this, as they would have been discovered
   1098 	     * in the initial Var_Subst and we wouldn't be here.
   1099 	     */
   1100 	    const char *nested_p = cp;
   1101 	    const char *nested_val;
   1102 	    void    *freeIt;
   1103 
   1104 	    (void)Var_Parse(&nested_p, VAR_CMD, VARE_UNDEFERR|VARE_WANTRES,
   1105 			    &nested_val, &freeIt);
   1106 	    /* TODO: handle errors */
   1107 	    free(freeIt);
   1108 	    cp += nested_p - cp;
   1109 	} else
   1110 	    cp++;
   1111     }
   1112 
   1113     *pp = cp;
   1114 }
   1115 
   1116 /* Parse a dependency line consisting of targets, followed by a dependency
   1117  * operator, optionally followed by sources.
   1118  *
   1119  * The nodes of the sources are linked as children to the nodes of the
   1120  * targets. Nodes are created as necessary.
   1121  *
   1122  * The operator is applied to each node in the global 'targets' list,
   1123  * which is where the nodes found for the targets are kept, by means of
   1124  * the ParseDoOp function.
   1125  *
   1126  * The sources are parsed in much the same way as the targets, except
   1127  * that they are expanded using the wildcarding scheme of the C-Shell,
   1128  * and all instances of the resulting words in the list of all targets
   1129  * are found. Each of the resulting nodes is then linked to each of the
   1130  * targets as one of its children.
   1131  *
   1132  * Certain targets and sources such as .PHONY or .PRECIOUS are handled
   1133  * specially. These are the ones detailed by the specType variable.
   1134  *
   1135  * The storing of transformation rules such as '.c.o' is also taken care of
   1136  * here. A target is recognized as a transformation rule by calling
   1137  * Suff_IsTransform. If it is a transformation rule, its node is gotten
   1138  * from the suffix module via Suff_AddTransform rather than the standard
   1139  * Targ_FindNode in the target module.
   1140  */
   1141 static void
   1142 ParseDoDependency(char *line)
   1143 {
   1144     typedef List SearchPathList;
   1145 
   1146     char *cp;			/* our current position */
   1147     GNodeType op;		/* the operator on the line */
   1148     char            savec;	/* a place to save a character */
   1149     SearchPathList *paths;	/* search paths to alter when parsing
   1150 				 * a list of .PATH targets */
   1151     int tOp;			/* operator from special target */
   1152     GNodeList *sources;		/* archive sources after expansion */
   1153     StringList *curTargs;	/* target names to be found and added
   1154 				 * to the targets list */
   1155     char	   *lstart = line;
   1156 
   1157     /*
   1158      * specType contains the SPECial TYPE of the current target. It is Not
   1159      * if the target is unspecial. If it *is* special, however, the children
   1160      * are linked as children of the parent but not vice versa.
   1161      */
   1162     ParseSpecial specType = Not;
   1163 
   1164     DEBUG1(PARSE, "ParseDoDependency(%s)\n", line);
   1165     tOp = 0;
   1166 
   1167     paths = NULL;
   1168 
   1169     curTargs = Lst_Init();
   1170 
   1171     /*
   1172      * First, grind through the targets.
   1173      */
   1174 
   1175     for (;;) {
   1176 	/*
   1177 	 * Here LINE points to the beginning of the next word, and
   1178 	 * LSTART points to the actual beginning of the line.
   1179 	 */
   1180 
   1181 	/* Find the end of the next word. */
   1182 	cp = line;
   1183 	ParseDependencyTargetWord(&cp, lstart);
   1184 
   1185 	/*
   1186 	 * If the word is followed by a left parenthesis, it's the
   1187 	 * name of an object file inside an archive (ar file).
   1188 	 */
   1189 	if (!ParseIsEscaped(lstart, cp) && *cp == '(') {
   1190 	    /*
   1191 	     * Archives must be handled specially to make sure the OP_ARCHV
   1192 	     * flag is set in their 'type' field, for one thing, and because
   1193 	     * things like "archive(file1.o file2.o file3.o)" are permissible.
   1194 	     * Arch_ParseArchive will set 'line' to be the first non-blank
   1195 	     * after the archive-spec. It creates/finds nodes for the members
   1196 	     * and places them on the given list, returning TRUE if all
   1197 	     * went well and FALSE if there was an error in the
   1198 	     * specification. On error, line should remain untouched.
   1199 	     */
   1200 	    if (!Arch_ParseArchive(&line, targets, VAR_CMD)) {
   1201 		Parse_Error(PARSE_FATAL,
   1202 			     "Error in archive specification: \"%s\"", line);
   1203 		goto out;
   1204 	    } else {
   1205 		/* Done with this word; on to the next. */
   1206 		cp = line;
   1207 		continue;
   1208 	    }
   1209 	}
   1210 
   1211 	if (!*cp) {
   1212 	    ParseErrorNoDependency(lstart, line);
   1213 	    goto out;
   1214 	}
   1215 
   1216 	/* Insert a null terminator. */
   1217 	savec = *cp;
   1218 	*cp = '\0';
   1219 
   1220 	/*
   1221 	 * Got the word. See if it's a special target and if so set
   1222 	 * specType to match it.
   1223 	 */
   1224 	if (*line == '.' && ch_isupper(line[1])) {
   1225 	    /*
   1226 	     * See if the target is a special target that must have it
   1227 	     * or its sources handled specially.
   1228 	     */
   1229 	    int keywd = ParseFindKeyword(line);
   1230 	    if (keywd != -1) {
   1231 		if (specType == ExPath && parseKeywords[keywd].spec != ExPath) {
   1232 		    Parse_Error(PARSE_FATAL, "Mismatched special targets");
   1233 		    goto out;
   1234 		}
   1235 
   1236 		specType = parseKeywords[keywd].spec;
   1237 		tOp = parseKeywords[keywd].op;
   1238 
   1239 		/*
   1240 		 * Certain special targets have special semantics:
   1241 		 *	.PATH		Have to set the dirSearchPath
   1242 		 *			variable too
   1243 		 *	.MAIN		Its sources are only used if
   1244 		 *			nothing has been specified to
   1245 		 *			create.
   1246 		 *	.DEFAULT	Need to create a node to hang
   1247 		 *			commands on, but we don't want
   1248 		 *			it in the graph, nor do we want
   1249 		 *			it to be the Main Target, so we
   1250 		 *			create it, set OP_NOTMAIN and
   1251 		 *			add it to the list, setting
   1252 		 *			DEFAULT to the new node for
   1253 		 *			later use. We claim the node is
   1254 		 *			A transformation rule to make
   1255 		 *			life easier later, when we'll
   1256 		 *			use Make_HandleUse to actually
   1257 		 *			apply the .DEFAULT commands.
   1258 		 *	.PHONY		The list of targets
   1259 		 *	.NOPATH		Don't search for file in the path
   1260 		 *	.STALE
   1261 		 *	.BEGIN
   1262 		 *	.END
   1263 		 *	.ERROR
   1264 		 *	.DELETE_ON_ERROR
   1265 		 *	.INTERRUPT	Are not to be considered the
   1266 		 *			main target.
   1267 		 *	.NOTPARALLEL	Make only one target at a time.
   1268 		 *	.SINGLESHELL	Create a shell for each command.
   1269 		 *	.ORDER		Must set initial predecessor to NULL
   1270 		 */
   1271 		switch (specType) {
   1272 		case ExPath:
   1273 		    if (paths == NULL) {
   1274 			paths = Lst_Init();
   1275 		    }
   1276 		    Lst_Append(paths, dirSearchPath);
   1277 		    break;
   1278 		case Main:
   1279 		    if (!Lst_IsEmpty(create)) {
   1280 			specType = Not;
   1281 		    }
   1282 		    break;
   1283 		case Begin:
   1284 		case End:
   1285 		case Stale:
   1286 		case dotError:
   1287 		case Interrupt: {
   1288 		    GNode *gn = Targ_GetNode(line);
   1289 		    if (doing_depend)
   1290 			ParseMark(gn);
   1291 		    gn->type |= OP_NOTMAIN|OP_SPECIAL;
   1292 		    Lst_Append(targets, gn);
   1293 		    break;
   1294 		}
   1295 		case Default: {
   1296 		    GNode *gn = Targ_NewGN(".DEFAULT");
   1297 		    gn->type |= OP_NOTMAIN|OP_TRANSFORM;
   1298 		    Lst_Append(targets, gn);
   1299 		    DEFAULT = gn;
   1300 		    break;
   1301 		}
   1302 		case DeleteOnError:
   1303 		    deleteOnError = TRUE;
   1304 		    break;
   1305 		case NotParallel:
   1306 		    maxJobs = 1;
   1307 		    break;
   1308 		case SingleShell:
   1309 		    compatMake = TRUE;
   1310 		    break;
   1311 		case Order:
   1312 		    predecessor = NULL;
   1313 		    break;
   1314 		default:
   1315 		    break;
   1316 		}
   1317 	    } else if (strncmp(line, ".PATH", 5) == 0) {
   1318 		/*
   1319 		 * .PATH<suffix> has to be handled specially.
   1320 		 * Call on the suffix module to give us a path to
   1321 		 * modify.
   1322 		 */
   1323 		SearchPath *path;
   1324 
   1325 		specType = ExPath;
   1326 		path = Suff_GetPath(&line[5]);
   1327 		if (path == NULL) {
   1328 		    Parse_Error(PARSE_FATAL,
   1329 				 "Suffix '%s' not defined (yet)",
   1330 				 &line[5]);
   1331 		    goto out;
   1332 		} else {
   1333 		    if (paths == NULL) {
   1334 			paths = Lst_Init();
   1335 		    }
   1336 		    Lst_Append(paths, path);
   1337 		}
   1338 	    }
   1339 	}
   1340 
   1341 	/*
   1342 	 * Have word in line. Get or create its node and stick it at
   1343 	 * the end of the targets list
   1344 	 */
   1345 	if (specType == Not && *line != '\0') {
   1346 	    if (Dir_HasWildcards(line)) {
   1347 		/*
   1348 		 * Targets are to be sought only in the current directory,
   1349 		 * so create an empty path for the thing. Note we need to
   1350 		 * use Dir_Destroy in the destruction of the path as the
   1351 		 * Dir module could have added a directory to the path...
   1352 		 */
   1353 		SearchPath *emptyPath = Lst_Init();
   1354 
   1355 		Dir_Expand(line, emptyPath, curTargs);
   1356 
   1357 		Lst_Destroy(emptyPath, Dir_Destroy);
   1358 	    } else {
   1359 		/*
   1360 		 * No wildcards, but we want to avoid code duplication,
   1361 		 * so create a list with the word on it.
   1362 		 */
   1363 		Lst_Append(curTargs, line);
   1364 	    }
   1365 
   1366 	    /* Apply the targets. */
   1367 
   1368 	    while(!Lst_IsEmpty(curTargs)) {
   1369 		char *targName = Lst_Dequeue(curTargs);
   1370 		GNode *gn = Suff_IsTransform(targName)
   1371 			    ? Suff_AddTransform(targName)
   1372 			    : Targ_GetNode(targName);
   1373 		if (doing_depend)
   1374 		    ParseMark(gn);
   1375 
   1376 		Lst_Append(targets, gn);
   1377 	    }
   1378 	} else if (specType == ExPath && *line != '.' && *line != '\0') {
   1379 	    Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", line);
   1380 	}
   1381 
   1382 	/* Don't need the inserted null terminator any more. */
   1383 	*cp = savec;
   1384 
   1385 	/*
   1386 	 * If it is a special type and not .PATH, it's the only target we
   1387 	 * allow on this line...
   1388 	 */
   1389 	if (specType != Not && specType != ExPath) {
   1390 	    Boolean warning = FALSE;
   1391 
   1392 	    while (*cp && (ParseIsEscaped(lstart, cp) ||
   1393 		(*cp != '!' && *cp != ':'))) {
   1394 		if (ParseIsEscaped(lstart, cp) ||
   1395 		    (*cp != ' ' && *cp != '\t')) {
   1396 		    warning = TRUE;
   1397 		}
   1398 		cp++;
   1399 	    }
   1400 	    if (warning) {
   1401 		Parse_Error(PARSE_WARNING, "Extra target ignored");
   1402 	    }
   1403 	} else {
   1404 	    pp_skip_whitespace(&cp);
   1405 	}
   1406 	line = cp;
   1407 	if (*line == '\0')
   1408 	    break;
   1409 	if ((*line == '!' || *line == ':') && !ParseIsEscaped(lstart, line))
   1410 	    break;
   1411     }
   1412 
   1413     /*
   1414      * Don't need the list of target names anymore...
   1415      */
   1416     Lst_Free(curTargs);
   1417     curTargs = NULL;
   1418 
   1419     if (!Lst_IsEmpty(targets)) {
   1420 	switch(specType) {
   1421 	    default:
   1422 		Parse_Error(PARSE_WARNING, "Special and mundane targets don't mix. Mundane ones ignored");
   1423 		break;
   1424 	    case Default:
   1425 	    case Stale:
   1426 	    case Begin:
   1427 	    case End:
   1428 	    case dotError:
   1429 	    case Interrupt:
   1430 		/*
   1431 		 * These four create nodes on which to hang commands, so
   1432 		 * targets shouldn't be empty...
   1433 		 */
   1434 	    case Not:
   1435 		/*
   1436 		 * Nothing special here -- targets can be empty if it wants.
   1437 		 */
   1438 		break;
   1439 	}
   1440     }
   1441 
   1442     /*
   1443      * Have now parsed all the target names. Must parse the operator next. The
   1444      * result is left in  op .
   1445      */
   1446     if (*cp == '!') {
   1447 	op = OP_FORCE;
   1448     } else if (*cp == ':') {
   1449 	if (cp[1] == ':') {
   1450 	    op = OP_DOUBLEDEP;
   1451 	    cp++;
   1452 	} else {
   1453 	    op = OP_DEPENDS;
   1454 	}
   1455     } else {
   1456 	Parse_Error(PARSE_FATAL, lstart[0] == '.' ? "Unknown directive"
   1457 		    : "Missing dependency operator");
   1458 	goto out;
   1459     }
   1460 
   1461     /* Advance beyond the operator */
   1462     cp++;
   1463 
   1464     /*
   1465      * Apply the operator to the target. This is how we remember which
   1466      * operator a target was defined with. It fails if the operator
   1467      * used isn't consistent across all references.
   1468      */
   1469     ApplyDependencyOperator(op);
   1470 
   1471     /*
   1472      * Onward to the sources.
   1473      *
   1474      * LINE will now point to the first source word, if any, or the
   1475      * end of the string if not.
   1476      */
   1477     pp_skip_whitespace(&cp);
   1478     line = cp;
   1479 
   1480     /*
   1481      * Several special targets take different actions if present with no
   1482      * sources:
   1483      *	a .SUFFIXES line with no sources clears out all old suffixes
   1484      *	a .PRECIOUS line makes all targets precious
   1485      *	a .IGNORE line ignores errors for all targets
   1486      *	a .SILENT line creates silence when making all targets
   1487      *	a .PATH removes all directories from the search path(s).
   1488      */
   1489     if (!*line) {
   1490 	switch (specType) {
   1491 	    case Suffixes:
   1492 		Suff_ClearSuffixes();
   1493 		break;
   1494 	    case Precious:
   1495 		allPrecious = TRUE;
   1496 		break;
   1497 	    case Ignore:
   1498 		ignoreErrors = TRUE;
   1499 		break;
   1500 	    case Silent:
   1501 		beSilent = TRUE;
   1502 		break;
   1503 	    case ExPath:
   1504 		if (paths != NULL)
   1505 		    Lst_ForEach(paths, ParseClearPath, NULL);
   1506 		Dir_SetPATH();
   1507 		break;
   1508 #ifdef POSIX
   1509 	    case Posix:
   1510 		Var_Set("%POSIX", "1003.2", VAR_GLOBAL);
   1511 		break;
   1512 #endif
   1513 	    default:
   1514 		break;
   1515 	}
   1516     } else if (specType == MFlags) {
   1517 	/*
   1518 	 * Call on functions in main.c to deal with these arguments and
   1519 	 * set the initial character to a null-character so the loop to
   1520 	 * get sources won't get anything
   1521 	 */
   1522 	Main_ParseArgLine(line);
   1523 	*line = '\0';
   1524     } else if (specType == ExShell) {
   1525 	if (!Job_ParseShell(line)) {
   1526 	    Parse_Error(PARSE_FATAL, "improper shell specification");
   1527 	    goto out;
   1528 	}
   1529 	*line = '\0';
   1530     } else if (specType == NotParallel || specType == SingleShell ||
   1531 	    specType == DeleteOnError) {
   1532 	*line = '\0';
   1533     }
   1534 
   1535     /*
   1536      * NOW GO FOR THE SOURCES
   1537      */
   1538     if (specType == Suffixes || specType == ExPath ||
   1539 	specType == Includes || specType == Libs ||
   1540 	specType == Null || specType == ExObjdir)
   1541     {
   1542 	while (*line) {
   1543 	    /*
   1544 	     * If the target was one that doesn't take files as its sources
   1545 	     * but takes something like suffixes, we take each
   1546 	     * space-separated word on the line as a something and deal
   1547 	     * with it accordingly.
   1548 	     *
   1549 	     * If the target was .SUFFIXES, we take each source as a
   1550 	     * suffix and add it to the list of suffixes maintained by the
   1551 	     * Suff module.
   1552 	     *
   1553 	     * If the target was a .PATH, we add the source as a directory
   1554 	     * to search on the search path.
   1555 	     *
   1556 	     * If it was .INCLUDES, the source is taken to be the suffix of
   1557 	     * files which will be #included and whose search path should
   1558 	     * be present in the .INCLUDES variable.
   1559 	     *
   1560 	     * If it was .LIBS, the source is taken to be the suffix of
   1561 	     * files which are considered libraries and whose search path
   1562 	     * should be present in the .LIBS variable.
   1563 	     *
   1564 	     * If it was .NULL, the source is the suffix to use when a file
   1565 	     * has no valid suffix.
   1566 	     *
   1567 	     * If it was .OBJDIR, the source is a new definition for .OBJDIR,
   1568 	     * and will cause make to do a new chdir to that path.
   1569 	     */
   1570 	    while (*cp && !ch_isspace(*cp)) {
   1571 		cp++;
   1572 	    }
   1573 	    savec = *cp;
   1574 	    *cp = '\0';
   1575 	    switch (specType) {
   1576 		case Suffixes:
   1577 		    Suff_AddSuffix(line, &mainNode);
   1578 		    break;
   1579 		case ExPath:
   1580 		    if (paths != NULL)
   1581 			Lst_ForEach(paths, ParseAddDir, line);
   1582 		    break;
   1583 		case Includes:
   1584 		    Suff_AddInclude(line);
   1585 		    break;
   1586 		case Libs:
   1587 		    Suff_AddLib(line);
   1588 		    break;
   1589 		case Null:
   1590 		    Suff_SetNull(line);
   1591 		    break;
   1592 		case ExObjdir:
   1593 		    Main_SetObjdir("%s", line);
   1594 		    break;
   1595 		default:
   1596 		    break;
   1597 	    }
   1598 	    *cp = savec;
   1599 	    if (savec != '\0') {
   1600 		cp++;
   1601 	    }
   1602 	    pp_skip_whitespace(&cp);
   1603 	    line = cp;
   1604 	}
   1605 	if (paths) {
   1606 	    Lst_Free(paths);
   1607 	    paths = NULL;
   1608 	}
   1609 	if (specType == ExPath)
   1610 	    Dir_SetPATH();
   1611     } else {
   1612 	assert(paths == NULL);
   1613 	while (*line) {
   1614 	    /*
   1615 	     * The targets take real sources, so we must beware of archive
   1616 	     * specifications (i.e. things with left parentheses in them)
   1617 	     * and handle them accordingly.
   1618 	     */
   1619 	    for (; *cp && !ch_isspace(*cp); cp++) {
   1620 		if (*cp == '(' && cp > line && cp[-1] != '$') {
   1621 		    /*
   1622 		     * Only stop for a left parenthesis if it isn't at the
   1623 		     * start of a word (that'll be for variable changes
   1624 		     * later) and isn't preceded by a dollar sign (a dynamic
   1625 		     * source).
   1626 		     */
   1627 		    break;
   1628 		}
   1629 	    }
   1630 
   1631 	    if (*cp == '(') {
   1632 		sources = Lst_Init();
   1633 		if (!Arch_ParseArchive(&line, sources, VAR_CMD)) {
   1634 		    Parse_Error(PARSE_FATAL,
   1635 				 "Error in source archive spec \"%s\"", line);
   1636 		    goto out;
   1637 		}
   1638 
   1639 		while (!Lst_IsEmpty(sources)) {
   1640 		    GNode *gn = Lst_Dequeue(sources);
   1641 		    ParseDoSrc(tOp, gn->name, specType);
   1642 		}
   1643 		Lst_Free(sources);
   1644 		cp = line;
   1645 	    } else {
   1646 		if (*cp) {
   1647 		    *cp = '\0';
   1648 		    cp++;
   1649 		}
   1650 
   1651 		ParseDoSrc(tOp, line, specType);
   1652 	    }
   1653 	    pp_skip_whitespace(&cp);
   1654 	    line = cp;
   1655 	}
   1656     }
   1657 
   1658     FindMainTarget();
   1659 
   1660 out:
   1661     if (paths != NULL)
   1662 	Lst_Free(paths);
   1663     if (curTargs != NULL)
   1664 	Lst_Free(curTargs);
   1665 }
   1666 
   1667 /* Parse a variable assignment, consisting of a single-word variable name,
   1668  * optional whitespace, an assignment operator, optional whitespace and the
   1669  * variable value.
   1670  *
   1671  * Used for both lines in a file and command line arguments. */
   1672 Boolean
   1673 Parse_IsVar(const char *p, VarAssign *out_var)
   1674 {
   1675     const char *firstSpace = NULL;
   1676     char ch;
   1677     int level = 0;
   1678 
   1679     /* Skip to variable name */
   1680     while (*p == ' ' || *p == '\t')
   1681 	p++;
   1682 
   1683     /* During parsing, the '+' of the '+=' operator is initially parsed
   1684      * as part of the variable name.  It is later corrected, as is the ':sh'
   1685      * modifier. Of these two (nameEnd and op), the earlier one determines the
   1686      * actual end of the variable name. */
   1687     out_var->nameStart = p;
   1688 #ifdef CLEANUP
   1689     out_var->nameEndDraft = NULL;
   1690     out_var->varname = NULL;
   1691     out_var->eq = NULL;
   1692     out_var->op = VAR_NORMAL;
   1693     out_var->value = NULL;
   1694 #endif
   1695 
   1696     /* Scan for one of the assignment operators outside a variable expansion */
   1697     while ((ch = *p++) != 0) {
   1698 	if (ch == '(' || ch == '{') {
   1699 	    level++;
   1700 	    continue;
   1701 	}
   1702 	if (ch == ')' || ch == '}') {
   1703 	    level--;
   1704 	    continue;
   1705 	}
   1706 
   1707 	if (level != 0)
   1708 	    continue;
   1709 
   1710 	if (ch == ' ' || ch == '\t')
   1711 	    if (firstSpace == NULL)
   1712 	        firstSpace = p - 1;
   1713 	while (ch == ' ' || ch == '\t')
   1714 	    ch = *p++;
   1715 
   1716 #ifdef SUNSHCMD
   1717 	if (ch == ':' && strncmp(p, "sh", 2) == 0) {
   1718 	    p += 2;
   1719 	    continue;
   1720 	}
   1721 #endif
   1722 	if (ch == '=') {
   1723 	    out_var->eq = p - 1;
   1724 	    out_var->nameEndDraft = firstSpace != NULL ? firstSpace : p - 1;
   1725 	    out_var->op = VAR_NORMAL;
   1726 	    cpp_skip_whitespace(&p);
   1727 	    out_var->value = p;
   1728 	    return TRUE;
   1729 	}
   1730 	if (*p == '=' && (ch == '+' || ch == ':' || ch == '?' || ch == '!')) {
   1731 	    out_var->eq = p;
   1732 	    out_var->nameEndDraft = firstSpace != NULL ? firstSpace : p;
   1733 	    out_var->op = ch == '+' ? VAR_APPEND :
   1734 			  ch == ':' ? VAR_SUBST :
   1735 			  ch == '?' ? VAR_DEFAULT : VAR_SHELL;
   1736 	    p++;
   1737 	    cpp_skip_whitespace(&p);
   1738 	    out_var->value = p;
   1739 	    return TRUE;
   1740 	}
   1741 	if (firstSpace != NULL)
   1742 	    return FALSE;
   1743     }
   1744 
   1745     return FALSE;
   1746 }
   1747 
   1748 /* Determine the assignment operator and adjust the end of the variable
   1749  * name accordingly. */
   1750 static void
   1751 ParseVarassignOp(VarAssign *var)
   1752 {
   1753     const char *op = var->eq;
   1754     const char * const name = var->nameStart;
   1755     VarAssignOp type;
   1756 
   1757     if (op > name && op[-1] == '+') {
   1758 	type = VAR_APPEND;
   1759 	op--;
   1760 
   1761     } else if (op > name && op[-1] == '?') {
   1762         op--;
   1763         type = VAR_DEFAULT;
   1764 
   1765     } else if (op > name && op[-1] == ':') {
   1766 	op--;
   1767 	type = VAR_SUBST;
   1768 
   1769     } else if (op > name && op[-1] == '!') {
   1770 	op--;
   1771 	type = VAR_SHELL;
   1772 
   1773     } else {
   1774 	type = VAR_NORMAL;
   1775 #ifdef SUNSHCMD
   1776 	while (op > name && ch_isspace(op[-1]))
   1777 	    op--;
   1778 
   1779 	if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
   1780 	    type = VAR_SHELL;
   1781 	    op -= 3;
   1782 	}
   1783 #endif
   1784     }
   1785 
   1786     {
   1787 	const char *nameEnd = var->nameEndDraft < op ? var->nameEndDraft : op;
   1788 	var->varname = bmake_strsedup(var->nameStart, nameEnd);
   1789 	var->op = type;
   1790     }
   1791 }
   1792 
   1793 static void
   1794 VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *ctxt)
   1795 {
   1796     if (DEBUG(LINT)) {
   1797 	if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
   1798 	    /* Check for syntax errors such as unclosed expressions or
   1799 	     * unknown modifiers. */
   1800 	    char *expandedValue;
   1801 
   1802 	    (void)Var_Subst(uvalue, ctxt, VARE_NONE, &expandedValue);
   1803 	    /* TODO: handle errors */
   1804 	    free(expandedValue);
   1805 	}
   1806     }
   1807 }
   1808 
   1809 static Boolean
   1810 VarAssign_Eval(VarAssign *var, GNode *ctxt,
   1811 	       const char **out_avalue, void **out_avalue_freeIt)
   1812 {
   1813     const char *uvalue = var->value;
   1814     const char *name = var->varname;
   1815     const VarAssignOp type = var->op;
   1816     const char *avalue = uvalue;
   1817     void *avalue_freeIt = NULL;
   1818 
   1819     if (type == VAR_APPEND) {
   1820 	Var_Append(name, uvalue, ctxt);
   1821     } else if (type == VAR_SUBST) {
   1822         char *evalue;
   1823 	/*
   1824 	 * Allow variables in the old value to be undefined, but leave their
   1825 	 * expressions alone -- this is done by forcing oldVars to be false.
   1826 	 * XXX: This can cause recursive variables, but that's not hard to do,
   1827 	 * and this allows someone to do something like
   1828 	 *
   1829 	 *  CFLAGS = $(.INCLUDES)
   1830 	 *  CFLAGS := -I.. $(CFLAGS)
   1831 	 *
   1832 	 * And not get an error.
   1833 	 */
   1834 	Boolean	  oldOldVars = oldVars;
   1835 
   1836 	oldVars = FALSE;
   1837 
   1838 	/*
   1839 	 * make sure that we set the variable the first time to nothing
   1840 	 * so that it gets substituted!
   1841 	 */
   1842 	if (!Var_Exists(name, ctxt))
   1843 	    Var_Set(name, "", ctxt);
   1844 
   1845 	(void)Var_Subst(uvalue, ctxt, VARE_WANTRES|VARE_ASSIGN, &evalue);
   1846 	/* TODO: handle errors */
   1847 	oldVars = oldOldVars;
   1848 	avalue = evalue;
   1849 	avalue_freeIt = evalue;
   1850 
   1851 	Var_Set(name, avalue, ctxt);
   1852     } else if (type == VAR_SHELL) {
   1853         const char *cmd, *errfmt;
   1854         char *cmdOut;
   1855         void *cmd_freeIt = NULL;
   1856 
   1857 	cmd = uvalue;
   1858 	if (strchr(cmd, '$') != NULL) {
   1859 	    char *ecmd;
   1860 	    (void)Var_Subst(cmd, VAR_CMD, VARE_UNDEFERR|VARE_WANTRES, &ecmd);
   1861 	    /* TODO: handle errors */
   1862 	    cmd = cmd_freeIt = ecmd;
   1863 	}
   1864 
   1865 	cmdOut = Cmd_Exec(cmd, &errfmt);
   1866 	Var_Set(name, cmdOut, ctxt);
   1867 	avalue = avalue_freeIt = cmdOut;
   1868 
   1869 	if (errfmt)
   1870 	    Parse_Error(PARSE_WARNING, errfmt, cmd);
   1871 
   1872 	free(cmd_freeIt);
   1873     } else {
   1874 	if (type == VAR_DEFAULT && Var_Exists(var->varname, ctxt)) {
   1875 	    *out_avalue_freeIt = NULL;
   1876 	    return FALSE;
   1877 	}
   1878 
   1879 	/* Normal assignment -- just do it. */
   1880 	Var_Set(name, uvalue, ctxt);
   1881     }
   1882 
   1883     *out_avalue = avalue;
   1884     *out_avalue_freeIt = avalue_freeIt;
   1885     return TRUE;
   1886 }
   1887 
   1888 static void
   1889 VarAssignSpecial(const char *name, const char *avalue)
   1890 {
   1891     if (strcmp(name, MAKEOVERRIDES) == 0)
   1892 	Main_ExportMAKEFLAGS(FALSE);	/* re-export MAKEFLAGS */
   1893     else if (strcmp(name, ".CURDIR") == 0) {
   1894 	/*
   1895 	 * Someone is being (too?) clever...
   1896 	 * Let's pretend they know what they are doing and
   1897 	 * re-initialize the 'cur' CachedDir.
   1898 	 */
   1899 	Dir_InitCur(avalue);
   1900 	Dir_SetPATH();
   1901     } else if (strcmp(name, MAKE_JOB_PREFIX) == 0) {
   1902 	Job_SetPrefix();
   1903     } else if (strcmp(name, MAKE_EXPORTED) == 0) {
   1904 	Var_Export(avalue, FALSE);
   1905     }
   1906 }
   1907 
   1908 /* Take the variable assignment in the passed line and execute it.
   1909  *
   1910  * Note: There is a lexical ambiguity with assignment modifier characters
   1911  * in variable names. This routine interprets the character before the =
   1912  * as a modifier. Therefore, an assignment like
   1913  *	C++=/usr/bin/CC
   1914  * is interpreted as "C+ +=" instead of "C++ =".
   1915  *
   1916  * Input:
   1917  *	p		A line guaranteed to be a variable assignment
   1918  *			(see Parse_IsVar).
   1919  *	ctxt		Context in which to do the assignment
   1920  */
   1921 void
   1922 Parse_DoVar(VarAssign *var, GNode *ctxt)
   1923 {
   1924     const char *avalue;		/* actual value (maybe expanded) */
   1925     void *avalue_freeIt;
   1926 
   1927     ParseVarassignOp(var);
   1928 
   1929     VarCheckSyntax(var->op, var->value, ctxt);
   1930     if (VarAssign_Eval(var, ctxt, &avalue, &avalue_freeIt))
   1931 	VarAssignSpecial(var->varname, avalue);
   1932 
   1933     free(avalue_freeIt);
   1934     free(var->varname);
   1935 }
   1936 
   1937 
   1938 /*
   1939  * ParseMaybeSubMake --
   1940  *	Scan the command string to see if it a possible submake node
   1941  * Input:
   1942  *	cmd		the command to scan
   1943  * Results:
   1944  *	TRUE if the command is possibly a submake, FALSE if not.
   1945  */
   1946 static Boolean
   1947 ParseMaybeSubMake(const char *cmd)
   1948 {
   1949     size_t i;
   1950     static struct {
   1951 	const char *name;
   1952 	size_t len;
   1953     } vals[] = {
   1954 #define MKV(A)	{	A, sizeof(A) - 1	}
   1955 	MKV("${MAKE}"),
   1956 	MKV("${.MAKE}"),
   1957 	MKV("$(MAKE)"),
   1958 	MKV("$(.MAKE)"),
   1959 	MKV("make"),
   1960     };
   1961     for (i = 0; i < sizeof(vals)/sizeof(vals[0]); i++) {
   1962 	char *ptr;
   1963 	if ((ptr = strstr(cmd, vals[i].name)) == NULL)
   1964 	    continue;
   1965 	if ((ptr == cmd || !ch_isalnum(ptr[-1]))
   1966 	    && !ch_isalnum(ptr[vals[i].len]))
   1967 	    return TRUE;
   1968     }
   1969     return FALSE;
   1970 }
   1971 
   1972 /* Append the command to the target node.
   1973  *
   1974  * The node may be marked as a submake node if the command is determined to
   1975  * be that. */
   1976 static void
   1977 ParseAddCmd(GNode *gn, char *cmd)
   1978 {
   1979     /* Add to last (ie current) cohort for :: targets */
   1980     if ((gn->type & OP_DOUBLEDEP) && gn->cohorts->last != NULL)
   1981 	gn = gn->cohorts->last->datum;
   1982 
   1983     /* if target already supplied, ignore commands */
   1984     if (!(gn->type & OP_HAS_COMMANDS)) {
   1985 	Lst_Append(gn->commands, cmd);
   1986 	if (ParseMaybeSubMake(cmd))
   1987 	    gn->type |= OP_SUBMAKE;
   1988 	ParseMark(gn);
   1989     } else {
   1990 #if 0
   1991 	/* XXX: We cannot do this until we fix the tree */
   1992 	Lst_Append(gn->commands, cmd);
   1993 	Parse_Error(PARSE_WARNING,
   1994 		     "overriding commands for target \"%s\"; "
   1995 		     "previous commands defined at %s: %d ignored",
   1996 		     gn->name, gn->fname, gn->lineno);
   1997 #else
   1998 	Parse_Error(PARSE_WARNING,
   1999 		     "duplicate script for target \"%s\" ignored",
   2000 		     gn->name);
   2001 	ParseErrorInternal(gn->fname, gn->lineno, PARSE_WARNING,
   2002 			    "using previous script for \"%s\" defined here",
   2003 			    gn->name);
   2004 #endif
   2005     }
   2006 }
   2007 
   2008 /* Callback procedure for Parse_File when destroying the list of targets on
   2009  * the last dependency line. Marks a target as already having commands if it
   2010  * does, to keep from having shell commands on multiple dependency lines. */
   2011 static void
   2012 ParseHasCommands(void *gnp)
   2013 {
   2014     GNode *gn = (GNode *)gnp;
   2015     if (!Lst_IsEmpty(gn->commands)) {
   2016 	gn->type |= OP_HAS_COMMANDS;
   2017     }
   2018 }
   2019 
   2020 /* Add a directory to the path searched for included makefiles bracketed
   2021  * by double-quotes. */
   2022 void
   2023 Parse_AddIncludeDir(const char *dir)
   2024 {
   2025     (void)Dir_AddDir(parseIncPath, dir);
   2026 }
   2027 
   2028 /* Push to another file.
   2029  *
   2030  * The input is the line minus the '.'. A file spec is a string enclosed in
   2031  * <> or "". The <> file is looked for only in sysIncPath. The "" file is
   2032  * first searched in the parsedir and then in the directories specified by
   2033  * the -I command line options.
   2034  */
   2035 static void
   2036 Parse_include_file(char *file, Boolean isSystem, Boolean depinc, int silent)
   2037 {
   2038     struct loadedfile *lf;
   2039     char          *fullname;	/* full pathname of file */
   2040     char          *newName;
   2041     char          *prefEnd, *incdir;
   2042     int           fd;
   2043     int           i;
   2044 
   2045     /*
   2046      * Now we know the file's name and its search path, we attempt to
   2047      * find the durn thing. A return of NULL indicates the file don't
   2048      * exist.
   2049      */
   2050     fullname = file[0] == '/' ? bmake_strdup(file) : NULL;
   2051 
   2052     if (fullname == NULL && !isSystem) {
   2053 	/*
   2054 	 * Include files contained in double-quotes are first searched for
   2055 	 * relative to the including file's location. We don't want to
   2056 	 * cd there, of course, so we just tack on the old file's
   2057 	 * leading path components and call Dir_FindFile to see if
   2058 	 * we can locate the beast.
   2059 	 */
   2060 
   2061 	incdir = bmake_strdup(curFile->fname);
   2062 	prefEnd = strrchr(incdir, '/');
   2063 	if (prefEnd != NULL) {
   2064 	    *prefEnd = '\0';
   2065 	    /* Now do lexical processing of leading "../" on the filename */
   2066 	    for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
   2067 		prefEnd = strrchr(incdir + 1, '/');
   2068 		if (prefEnd == NULL || strcmp(prefEnd, "/..") == 0)
   2069 		    break;
   2070 		*prefEnd = '\0';
   2071 	    }
   2072 	    newName = str_concat3(incdir, "/", file + i);
   2073 	    fullname = Dir_FindFile(newName, parseIncPath);
   2074 	    if (fullname == NULL)
   2075 		fullname = Dir_FindFile(newName, dirSearchPath);
   2076 	    free(newName);
   2077 	}
   2078 	free(incdir);
   2079 
   2080 	if (fullname == NULL) {
   2081 	    /*
   2082 	     * Makefile wasn't found in same directory as included makefile.
   2083 	     * Search for it first on the -I search path,
   2084 	     * then on the .PATH search path, if not found in a -I directory.
   2085 	     * If we have a suffix specific path we should use that.
   2086 	     */
   2087 	    char *suff;
   2088 	    SearchPath *suffPath = NULL;
   2089 
   2090 	    if ((suff = strrchr(file, '.'))) {
   2091 		suffPath = Suff_GetPath(suff);
   2092 		if (suffPath != NULL) {
   2093 		    fullname = Dir_FindFile(file, suffPath);
   2094 		}
   2095 	    }
   2096 	    if (fullname == NULL) {
   2097 		fullname = Dir_FindFile(file, parseIncPath);
   2098 		if (fullname == NULL) {
   2099 		    fullname = Dir_FindFile(file, dirSearchPath);
   2100 		}
   2101 	    }
   2102 	}
   2103     }
   2104 
   2105     /* Looking for a system file or file still not found */
   2106     if (fullname == NULL) {
   2107 	/*
   2108 	 * Look for it on the system path
   2109 	 */
   2110 	fullname = Dir_FindFile(file,
   2111 		    Lst_IsEmpty(sysIncPath) ? defIncPath : sysIncPath);
   2112     }
   2113 
   2114     if (fullname == NULL) {
   2115 	if (!silent)
   2116 	    Parse_Error(PARSE_FATAL, "Could not find %s", file);
   2117 	return;
   2118     }
   2119 
   2120     /* Actually open the file... */
   2121     fd = open(fullname, O_RDONLY);
   2122     if (fd == -1) {
   2123 	if (!silent)
   2124 	    Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
   2125 	free(fullname);
   2126 	return;
   2127     }
   2128 
   2129     /* load it */
   2130     lf = loadfile(fullname, fd);
   2131 
   2132     /* Start reading from this file next */
   2133     Parse_SetInput(fullname, 0, -1, loadedfile_nextbuf, lf);
   2134     curFile->lf = lf;
   2135     if (depinc)
   2136 	doing_depend = depinc;		/* only turn it on */
   2137 }
   2138 
   2139 static void
   2140 ParseDoInclude(char *line)
   2141 {
   2142     char          endc;		/* the character which ends the file spec */
   2143     char          *cp;		/* current position in file spec */
   2144     int		  silent = *line != 'i';
   2145     char	  *file = &line[7 + silent];
   2146 
   2147     /* Skip to delimiter character so we know where to look */
   2148     while (*file == ' ' || *file == '\t')
   2149 	file++;
   2150 
   2151     if (*file != '"' && *file != '<') {
   2152 	Parse_Error(PARSE_FATAL,
   2153 	    ".include filename must be delimited by '\"' or '<'");
   2154 	return;
   2155     }
   2156 
   2157     /*
   2158      * Set the search path on which to find the include file based on the
   2159      * characters which bracket its name. Angle-brackets imply it's
   2160      * a system Makefile while double-quotes imply it's a user makefile
   2161      */
   2162     if (*file == '<') {
   2163 	endc = '>';
   2164     } else {
   2165 	endc = '"';
   2166     }
   2167 
   2168     /* Skip to matching delimiter */
   2169     for (cp = ++file; *cp && *cp != endc; cp++)
   2170 	continue;
   2171 
   2172     if (*cp != endc) {
   2173 	Parse_Error(PARSE_FATAL,
   2174 		     "Unclosed %cinclude filename. '%c' expected",
   2175 		     '.', endc);
   2176 	return;
   2177     }
   2178     *cp = '\0';
   2179 
   2180     /*
   2181      * Substitute for any variables in the file name before trying to
   2182      * find the thing.
   2183      */
   2184     (void)Var_Subst(file, VAR_CMD, VARE_WANTRES, &file);
   2185     /* TODO: handle errors */
   2186 
   2187     Parse_include_file(file, endc == '>', *line == 'd', silent);
   2188     free(file);
   2189 }
   2190 
   2191 /* Split filename into dirname + basename, then assign these to the
   2192  * given variables. */
   2193 static void
   2194 SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
   2195 {
   2196     const char *slash, *dirname, *basename;
   2197     void *freeIt;
   2198 
   2199     slash = strrchr(filename, '/');
   2200     if (slash == NULL) {
   2201 	dirname = curdir;
   2202 	basename = filename;
   2203 	freeIt = NULL;
   2204     } else {
   2205 	dirname = freeIt = bmake_strsedup(filename, slash);
   2206 	basename = slash + 1;
   2207     }
   2208 
   2209     Var_Set(dirvar, dirname, VAR_GLOBAL);
   2210     Var_Set(filevar, basename, VAR_GLOBAL);
   2211 
   2212     DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
   2213 	   __func__, dirvar, dirname, filevar, basename);
   2214     free(freeIt);
   2215 }
   2216 
   2217 /* Return the immediately including file.
   2218  *
   2219  * This is made complicated since the .for loop is implemented as a special
   2220  * kind of .include; see For_Run. */
   2221 static const char *
   2222 GetActuallyIncludingFile(void)
   2223 {
   2224     size_t i;
   2225 
   2226     /* XXX: Stack was supposed to be an opaque data structure. */
   2227     for (i = includes.len; i > 0; i--) {
   2228 	IFile *parent = includes.items[i - 1];
   2229 	IFile *child = i < includes.len ? includes.items[i] : curFile;
   2230 	if (!child->fromForLoop)
   2231 	    return parent->fname;
   2232     }
   2233     return NULL;
   2234 }
   2235 
   2236 /* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
   2237 static void
   2238 ParseSetParseFile(const char *filename)
   2239 {
   2240     const char *including;
   2241 
   2242     SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");
   2243 
   2244     including = GetActuallyIncludingFile();
   2245     if (including != NULL) {
   2246 	SetFilenameVars(including,
   2247 			".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
   2248     } else {
   2249 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
   2250 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
   2251     }
   2252 }
   2253 
   2254 /* Track the makefiles we read - so makefiles can set dependencies on them.
   2255  * Avoid adding anything more than once. */
   2256 static void
   2257 ParseTrackInput(const char *name)
   2258 {
   2259     char *fp = NULL;
   2260 
   2261     const char *old = Var_Value(MAKE_MAKEFILES, VAR_GLOBAL, &fp);
   2262     if (old) {
   2263 	size_t name_len = strlen(name);
   2264 	const char *ep = old + strlen(old) - name_len;
   2265 	/* does it contain name? */
   2266 	for (; old != NULL; old = strchr(old, ' ')) {
   2267 	    if (*old == ' ')
   2268 		old++;
   2269 	    if (old >= ep)
   2270 		break;			/* cannot contain name */
   2271 	    if (memcmp(old, name, name_len) == 0
   2272 		    && (old[name_len] == 0 || old[name_len] == ' '))
   2273 		goto cleanup;
   2274 	}
   2275     }
   2276     Var_Append (MAKE_MAKEFILES, name, VAR_GLOBAL);
   2277  cleanup:
   2278     bmake_free(fp);
   2279 }
   2280 
   2281 
   2282 /* Start Parsing from the given source.
   2283  *
   2284  * The given file is added to the includes stack. */
   2285 void
   2286 Parse_SetInput(const char *name, int line, int fd,
   2287 	char *(*nextbuf)(void *, size_t *), void *arg)
   2288 {
   2289     char *buf;
   2290     size_t len;
   2291     Boolean fromForLoop = name == NULL;
   2292 
   2293     if (fromForLoop)
   2294 	name = curFile->fname;
   2295     else
   2296 	ParseTrackInput(name);
   2297 
   2298     if (DEBUG(PARSE))
   2299 	debug_printf("%s: file %s, line %d, fd %d, nextbuf %s, arg %p\n",
   2300 		     __func__, name, line, fd,
   2301 		     nextbuf == loadedfile_nextbuf ? "loadedfile" : "other",
   2302 		     arg);
   2303 
   2304     if (fd == -1 && nextbuf == NULL)
   2305 	/* sanity */
   2306 	return;
   2307 
   2308     if (curFile != NULL)
   2309 	/* Save existing file info */
   2310 	Stack_Push(&includes, curFile);
   2311 
   2312     /* Allocate and fill in new structure */
   2313     curFile = bmake_malloc(sizeof *curFile);
   2314 
   2315     /*
   2316      * Once the previous state has been saved, we can get down to reading
   2317      * the new file. We set up the name of the file to be the absolute
   2318      * name of the include file so error messages refer to the right
   2319      * place.
   2320      */
   2321     curFile->fname = bmake_strdup(name);
   2322     curFile->fromForLoop = fromForLoop;
   2323     curFile->lineno = line;
   2324     curFile->first_lineno = line;
   2325     curFile->nextbuf = nextbuf;
   2326     curFile->nextbuf_arg = arg;
   2327     curFile->lf = NULL;
   2328     curFile->depending = doing_depend;	/* restore this on EOF */
   2329 
   2330     assert(nextbuf != NULL);
   2331 
   2332     /* Get first block of input data */
   2333     buf = curFile->nextbuf(curFile->nextbuf_arg, &len);
   2334     if (buf == NULL) {
   2335 	/* Was all a waste of time ... */
   2336 	if (curFile->fname)
   2337 	    free(curFile->fname);
   2338 	free(curFile);
   2339 	return;
   2340     }
   2341     curFile->P_str = buf;
   2342     curFile->P_ptr = buf;
   2343     curFile->P_end = buf+len;
   2344 
   2345     curFile->cond_depth = Cond_save_depth();
   2346     ParseSetParseFile(name);
   2347 }
   2348 
   2349 /* Check if the line is an include directive. */
   2350 static Boolean
   2351 IsInclude(const char *dir, Boolean sysv)
   2352 {
   2353 	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
   2354 		dir++;
   2355 
   2356 	if (strncmp(dir, "include", 7) != 0)
   2357 		return FALSE;
   2358 
   2359 	/* Space is not mandatory for BSD .include */
   2360 	return !sysv || ch_isspace(dir[7]);
   2361 }
   2362 
   2363 
   2364 #ifdef SYSVINCLUDE
   2365 /* Check if the line is a SYSV include directive. */
   2366 static Boolean
   2367 IsSysVInclude(const char *line)
   2368 {
   2369 	const char *p;
   2370 
   2371 	if (!IsInclude(line, TRUE))
   2372 		return FALSE;
   2373 
   2374 	/* Avoid interpeting a dependency line as an include */
   2375 	for (p = line; (p = strchr(p, ':')) != NULL;) {
   2376 		if (*++p == '\0') {
   2377 			/* end of line -> dependency */
   2378 			return FALSE;
   2379 		}
   2380 		if (*p == ':' || ch_isspace(*p)) {
   2381 			/* :: operator or ': ' -> dependency */
   2382 			return FALSE;
   2383 		}
   2384 	}
   2385 	return TRUE;
   2386 }
   2387 
   2388 /* Push to another file.  The line points to the word "include". */
   2389 static void
   2390 ParseTraditionalInclude(char *line)
   2391 {
   2392     char          *cp;		/* current position in file spec */
   2393     int		   done = 0;
   2394     int		   silent = line[0] != 'i';
   2395     char	  *file = &line[silent + 7];
   2396     char	  *all_files;
   2397 
   2398     DEBUG2(PARSE, "%s: %s\n", __func__, file);
   2399 
   2400     pp_skip_whitespace(&file);
   2401 
   2402     /*
   2403      * Substitute for any variables in the file name before trying to
   2404      * find the thing.
   2405      */
   2406     (void)Var_Subst(file, VAR_CMD, VARE_WANTRES, &all_files);
   2407     /* TODO: handle errors */
   2408 
   2409     if (*file == '\0') {
   2410 	Parse_Error(PARSE_FATAL,
   2411 		     "Filename missing from \"include\"");
   2412 	goto out;
   2413     }
   2414 
   2415     for (file = all_files; !done; file = cp + 1) {
   2416 	/* Skip to end of line or next whitespace */
   2417 	for (cp = file; *cp && !ch_isspace(*cp); cp++)
   2418 	    continue;
   2419 
   2420 	if (*cp)
   2421 	    *cp = '\0';
   2422 	else
   2423 	    done = 1;
   2424 
   2425 	Parse_include_file(file, FALSE, FALSE, silent);
   2426     }
   2427 out:
   2428     free(all_files);
   2429 }
   2430 #endif
   2431 
   2432 #ifdef GMAKEEXPORT
   2433 /* Parse export <variable>=<value>, and actually export it. */
   2434 static void
   2435 ParseGmakeExport(char *line)
   2436 {
   2437     char	  *variable = &line[6];
   2438     char	  *value;
   2439 
   2440     DEBUG2(PARSE, "%s: %s\n", __func__, variable);
   2441 
   2442     pp_skip_whitespace(&variable);
   2443 
   2444     for (value = variable; *value && *value != '='; value++)
   2445 	continue;
   2446 
   2447     if (*value != '=') {
   2448 	Parse_Error(PARSE_FATAL,
   2449 		    "Variable/Value missing from \"export\"");
   2450 	return;
   2451     }
   2452     *value++ = '\0';			/* terminate variable */
   2453 
   2454     /*
   2455      * Expand the value before putting it in the environment.
   2456      */
   2457     (void)Var_Subst(value, VAR_CMD, VARE_WANTRES, &value);
   2458     /* TODO: handle errors */
   2459 
   2460     setenv(variable, value, 1);
   2461     free(value);
   2462 }
   2463 #endif
   2464 
   2465 /* Called when EOF is reached in the current file. If we were reading an
   2466  * include file, the includes stack is popped and things set up to go back
   2467  * to reading the previous file at the previous location.
   2468  *
   2469  * Results:
   2470  *	CONTINUE if there's more to do. DONE if not.
   2471  */
   2472 static int
   2473 ParseEOF(void)
   2474 {
   2475     char *ptr;
   2476     size_t len;
   2477 
   2478     assert(curFile->nextbuf != NULL);
   2479 
   2480     doing_depend = curFile->depending;	/* restore this */
   2481     /* get next input buffer, if any */
   2482     ptr = curFile->nextbuf(curFile->nextbuf_arg, &len);
   2483     curFile->P_ptr = ptr;
   2484     curFile->P_str = ptr;
   2485     curFile->P_end = ptr + len;
   2486     curFile->lineno = curFile->first_lineno;
   2487     if (ptr != NULL) {
   2488 	/* Iterate again */
   2489 	return CONTINUE;
   2490     }
   2491 
   2492     /* Ensure the makefile (or loop) didn't have mismatched conditionals */
   2493     Cond_restore_depth(curFile->cond_depth);
   2494 
   2495     if (curFile->lf != NULL) {
   2496 	    loadedfile_destroy(curFile->lf);
   2497 	    curFile->lf = NULL;
   2498     }
   2499 
   2500     /* Dispose of curFile info */
   2501     /* Leak curFile->fname because all the gnodes have pointers to it */
   2502     free(curFile->P_str);
   2503     free(curFile);
   2504 
   2505     if (Stack_IsEmpty(&includes)) {
   2506 	curFile = NULL;
   2507 	/* We've run out of input */
   2508 	Var_Delete(".PARSEDIR", VAR_GLOBAL);
   2509 	Var_Delete(".PARSEFILE", VAR_GLOBAL);
   2510 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
   2511 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
   2512 	return DONE;
   2513     }
   2514 
   2515     curFile = Stack_Pop(&includes);
   2516     DEBUG2(PARSE, "ParseEOF: returning to file %s, line %d\n",
   2517 	   curFile->fname, curFile->lineno);
   2518 
   2519     ParseSetParseFile(curFile->fname);
   2520     return CONTINUE;
   2521 }
   2522 
   2523 #define PARSE_RAW 1
   2524 #define PARSE_SKIP 2
   2525 
   2526 static char *
   2527 ParseGetLine(int flags)
   2528 {
   2529     IFile *cf = curFile;
   2530     char *ptr;
   2531     char ch;
   2532     char *line;
   2533     char *line_end;
   2534     char *escaped;
   2535     char *comment;
   2536     char *tp;
   2537 
   2538     /* Loop through blank lines and comment lines */
   2539     for (;;) {
   2540 	cf->lineno++;
   2541 	line = cf->P_ptr;
   2542 	ptr = line;
   2543 	line_end = line;
   2544 	escaped = NULL;
   2545 	comment = NULL;
   2546 	for (;;) {
   2547 	    if (cf->P_end != NULL && ptr == cf->P_end) {
   2548 		/* end of buffer */
   2549 		ch = 0;
   2550 		break;
   2551 	    }
   2552 	    ch = *ptr;
   2553 	    if (ch == 0 || (ch == '\\' && ptr[1] == 0)) {
   2554 		if (cf->P_end == NULL)
   2555 		    /* End of string (aka for loop) data */
   2556 		    break;
   2557 		/* see if there is more we can parse */
   2558 		while (ptr++ < cf->P_end) {
   2559 		    if ((ch = *ptr) == '\n') {
   2560 			if (ptr > line && ptr[-1] == '\\')
   2561 			    continue;
   2562 			Parse_Error(PARSE_WARNING,
   2563 			    "Zero byte read from file, skipping rest of line.");
   2564 			break;
   2565 		    }
   2566 		}
   2567 		if (cf->nextbuf != NULL) {
   2568 		    /*
   2569 		     * End of this buffer; return EOF and outer logic
   2570 		     * will get the next one. (eww)
   2571 		     */
   2572 		    break;
   2573 		}
   2574 		Parse_Error(PARSE_FATAL, "Zero byte read from file");
   2575 		return NULL;
   2576 	    }
   2577 
   2578 	    if (ch == '\\') {
   2579 		/* Don't treat next character as special, remember first one */
   2580 		if (escaped == NULL)
   2581 		    escaped = ptr;
   2582 		if (ptr[1] == '\n')
   2583 		    cf->lineno++;
   2584 		ptr += 2;
   2585 		line_end = ptr;
   2586 		continue;
   2587 	    }
   2588 	    if (ch == '#' && comment == NULL) {
   2589 		/* Remember first '#' for comment stripping */
   2590 		/* Unless previous char was '[', as in modifier :[#] */
   2591 		if (!(ptr > line && ptr[-1] == '['))
   2592 		    comment = line_end;
   2593 	    }
   2594 	    ptr++;
   2595 	    if (ch == '\n')
   2596 		break;
   2597 	    if (!ch_isspace(ch))
   2598 		/* We are not interested in trailing whitespace */
   2599 		line_end = ptr;
   2600 	}
   2601 
   2602 	/* Save next 'to be processed' location */
   2603 	cf->P_ptr = ptr;
   2604 
   2605 	/* Check we have a non-comment, non-blank line */
   2606 	if (line_end == line || comment == line) {
   2607 	    if (ch == 0)
   2608 		/* At end of file */
   2609 		return NULL;
   2610 	    /* Parse another line */
   2611 	    continue;
   2612 	}
   2613 
   2614 	/* We now have a line of data */
   2615 	*line_end = 0;
   2616 
   2617 	if (flags & PARSE_RAW) {
   2618 	    /* Leave '\' (etc) in line buffer (eg 'for' lines) */
   2619 	    return line;
   2620 	}
   2621 
   2622 	if (flags & PARSE_SKIP) {
   2623 	    /* Completely ignore non-directives */
   2624 	    if (line[0] != '.')
   2625 		continue;
   2626 	    /* We could do more of the .else/.elif/.endif checks here */
   2627 	}
   2628 	break;
   2629     }
   2630 
   2631     /* Brutally ignore anything after a non-escaped '#' in non-commands */
   2632     if (comment != NULL && line[0] != '\t') {
   2633 	line_end = comment;
   2634 	*line_end = 0;
   2635     }
   2636 
   2637     /* If we didn't see a '\\' then the in-situ data is fine */
   2638     if (escaped == NULL)
   2639 	return line;
   2640 
   2641     /* Remove escapes from '\n' and '#' */
   2642     tp = ptr = escaped;
   2643     escaped = line;
   2644     for (; ; *tp++ = ch) {
   2645 	ch = *ptr++;
   2646 	if (ch != '\\') {
   2647 	    if (ch == 0)
   2648 		break;
   2649 	    continue;
   2650 	}
   2651 
   2652 	ch = *ptr++;
   2653 	if (ch == 0) {
   2654 	    /* Delete '\\' at end of buffer */
   2655 	    tp--;
   2656 	    break;
   2657 	}
   2658 
   2659 	if (ch == '#' && line[0] != '\t')
   2660 	    /* Delete '\\' from before '#' on non-command lines */
   2661 	    continue;
   2662 
   2663 	if (ch != '\n') {
   2664 	    /* Leave '\\' in buffer for later */
   2665 	    *tp++ = '\\';
   2666 	    /* Make sure we don't delete an escaped ' ' from the line end */
   2667 	    escaped = tp + 1;
   2668 	    continue;
   2669 	}
   2670 
   2671 	/* Escaped '\n' replace following whitespace with a single ' ' */
   2672 	while (ptr[0] == ' ' || ptr[0] == '\t')
   2673 	    ptr++;
   2674 	ch = ' ';
   2675     }
   2676 
   2677     /* Delete any trailing spaces - eg from empty continuations */
   2678     while (tp > escaped && ch_isspace(tp[-1]))
   2679 	tp--;
   2680 
   2681     *tp = 0;
   2682     return line;
   2683 }
   2684 
   2685 /* Read an entire line from the input file. Called only by Parse_File.
   2686  *
   2687  * Results:
   2688  *	A line without its newline.
   2689  *
   2690  * Side Effects:
   2691  *	Only those associated with reading a character
   2692  */
   2693 static char *
   2694 ParseReadLine(void)
   2695 {
   2696     char *line;			/* Result */
   2697     int lineno;			/* Saved line # */
   2698     int rval;
   2699 
   2700     for (;;) {
   2701 	line = ParseGetLine(0);
   2702 	if (line == NULL)
   2703 	    return NULL;
   2704 
   2705 	if (line[0] != '.')
   2706 	    return line;
   2707 
   2708 	/*
   2709 	 * The line might be a conditional. Ask the conditional module
   2710 	 * about it and act accordingly
   2711 	 */
   2712 	switch (Cond_EvalLine(line)) {
   2713 	case COND_SKIP:
   2714 	    /* Skip to next conditional that evaluates to COND_PARSE.  */
   2715 	    do {
   2716 		line = ParseGetLine(PARSE_SKIP);
   2717 	    } while (line && Cond_EvalLine(line) != COND_PARSE);
   2718 	    if (line == NULL)
   2719 		break;
   2720 	    continue;
   2721 	case COND_PARSE:
   2722 	    continue;
   2723 	case COND_INVALID:    /* Not a conditional line */
   2724 	    /* Check for .for loops */
   2725 	    rval = For_Eval(line);
   2726 	    if (rval == 0)
   2727 		/* Not a .for line */
   2728 		break;
   2729 	    if (rval < 0)
   2730 		/* Syntax error - error printed, ignore line */
   2731 		continue;
   2732 	    /* Start of a .for loop */
   2733 	    lineno = curFile->lineno;
   2734 	    /* Accumulate loop lines until matching .endfor */
   2735 	    do {
   2736 		line = ParseGetLine(PARSE_RAW);
   2737 		if (line == NULL) {
   2738 		    Parse_Error(PARSE_FATAL,
   2739 			     "Unexpected end of file in for loop.");
   2740 		    break;
   2741 		}
   2742 	    } while (For_Accum(line));
   2743 	    /* Stash each iteration as a new 'input file' */
   2744 	    For_Run(lineno);
   2745 	    /* Read next line from for-loop buffer */
   2746 	    continue;
   2747 	}
   2748 	return line;
   2749     }
   2750 }
   2751 
   2752 static void
   2753 SuffEndTransform(void *target, void *unused MAKE_ATTR_UNUSED)
   2754 {
   2755     Suff_EndTransform(target);
   2756 }
   2757 
   2758 static void
   2759 FinishDependencyGroup(void)
   2760 {
   2761     if (targets != NULL) {
   2762 	Lst_ForEach(targets, SuffEndTransform, NULL);
   2763 	Lst_Destroy(targets, ParseHasCommands);
   2764 	targets = NULL;
   2765     }
   2766 }
   2767 
   2768 /* Add the command to each target from the current dependency spec. */
   2769 static void
   2770 ParseLine_ShellCommand(char *cp)
   2771 {
   2772     pp_skip_whitespace(&cp);
   2773     if (*cp == '\0')
   2774 	return;			/* skip empty commands */
   2775 
   2776     if (targets == NULL) {
   2777 	Parse_Error(PARSE_FATAL, "Unassociated shell command \"%s\"", cp);
   2778 	return;
   2779     }
   2780 
   2781     {
   2782 	char *cmd = bmake_strdup(cp);
   2783 	GNodeListNode *ln;
   2784 
   2785 	for (ln = targets->first; ln != NULL; ln = ln->next) {
   2786 	    GNode *gn = ln->datum;
   2787 	    ParseAddCmd(gn, cmd);
   2788 	}
   2789 #ifdef CLEANUP
   2790 	Lst_Append(targCmds, cmd);
   2791 #endif
   2792     }
   2793 }
   2794 
   2795 /* Parse a top-level makefile into its component parts, incorporating them
   2796  * into the global dependency graph.
   2797  *
   2798  * Input:
   2799  *	name		The name of the file being read
   2800  *	fd		The open file to parse; will be closed at the end
   2801  */
   2802 void
   2803 Parse_File(const char *name, int fd)
   2804 {
   2805     char	  *cp;		/* pointer into the line */
   2806     char          *line;	/* the line we're working on */
   2807     struct loadedfile *lf;
   2808 
   2809     lf = loadfile(name, fd);
   2810 
   2811     assert(targets == NULL);
   2812     fatals = 0;
   2813 
   2814     if (name == NULL)
   2815 	name = "(stdin)";
   2816 
   2817     Parse_SetInput(name, 0, -1, loadedfile_nextbuf, lf);
   2818     curFile->lf = lf;
   2819 
   2820     do {
   2821 	for (; (line = ParseReadLine()) != NULL; ) {
   2822 	    DEBUG2(PARSE, "ParseReadLine (%d): '%s'\n", curFile->lineno, line);
   2823 	    if (*line == '.') {
   2824 		/*
   2825 		 * Lines that begin with the special character may be
   2826 		 * include or undef directives.
   2827 		 * On the other hand they can be suffix rules (.c.o: ...)
   2828 		 * or just dependencies for filenames that start '.'.
   2829 		 */
   2830 		cp = line + 1;
   2831 		pp_skip_whitespace(&cp);
   2832 		if (IsInclude(cp, FALSE)) {
   2833 		    ParseDoInclude(cp);
   2834 		    continue;
   2835 		}
   2836 		if (strncmp(cp, "undef", 5) == 0) {
   2837 		    const char *varname;
   2838 		    cp += 5;
   2839 		    pp_skip_whitespace(&cp);
   2840 		    varname = cp;
   2841 		    for (; !ch_isspace(*cp) && *cp != '\0'; cp++)
   2842 			continue;
   2843 		    *cp = '\0';
   2844 		    Var_Delete(varname, VAR_GLOBAL);
   2845 		    /* TODO: undefine all variables, not only the first */
   2846 		    /* TODO: use Str_Words, like everywhere else */
   2847 		    continue;
   2848 		} else if (strncmp(cp, "export", 6) == 0) {
   2849 		    cp += 6;
   2850 		    pp_skip_whitespace(&cp);
   2851 		    Var_Export(cp, TRUE);
   2852 		    continue;
   2853 		} else if (strncmp(cp, "unexport", 8) == 0) {
   2854 		    Var_UnExport(cp);
   2855 		    continue;
   2856 		} else if (strncmp(cp, "info", 4) == 0 ||
   2857 			   strncmp(cp, "error", 5) == 0 ||
   2858 			   strncmp(cp, "warning", 7) == 0) {
   2859 		    if (ParseMessage(cp))
   2860 			continue;
   2861 		}
   2862 	    }
   2863 
   2864 	    if (*line == '\t') {
   2865 		/*
   2866 		 * If a line starts with a tab, it can only hope to be
   2867 		 * a creation command.
   2868 		 */
   2869 		cp = line + 1;
   2870 	      shellCommand:
   2871 	        ParseLine_ShellCommand(cp);
   2872 		continue;
   2873 	    }
   2874 
   2875 #ifdef SYSVINCLUDE
   2876 	    if (IsSysVInclude(line)) {
   2877 		/*
   2878 		 * It's an S3/S5-style "include".
   2879 		 */
   2880 		ParseTraditionalInclude(line);
   2881 		continue;
   2882 	    }
   2883 #endif
   2884 #ifdef GMAKEEXPORT
   2885 	    if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
   2886 		strchr(line, ':') == NULL) {
   2887 		/*
   2888 		 * It's a Gmake "export".
   2889 		 */
   2890 		ParseGmakeExport(line);
   2891 		continue;
   2892 	    }
   2893 #endif
   2894 	    {
   2895 	        VarAssign var;
   2896 		if (Parse_IsVar(line, &var)) {
   2897 		    FinishDependencyGroup();
   2898 		    Parse_DoVar(&var, VAR_GLOBAL);
   2899 		    continue;
   2900 		}
   2901 	    }
   2902 
   2903 #ifndef POSIX
   2904 	    /*
   2905 	     * To make life easier on novices, if the line is indented we
   2906 	     * first make sure the line has a dependency operator in it.
   2907 	     * If it doesn't have an operator and we're in a dependency
   2908 	     * line's script, we assume it's actually a shell command
   2909 	     * and add it to the current list of targets.
   2910 	     */
   2911 	    cp = line;
   2912 	    if (ch_isspace(line[0])) {
   2913 		pp_skip_whitespace(&cp);
   2914 		while (*cp && (ParseIsEscaped(line, cp) ||
   2915 			*cp != ':' && *cp != '!')) {
   2916 		    cp++;
   2917 		}
   2918 		if (*cp == '\0') {
   2919 		    if (targets == NULL) {
   2920 			Parse_Error(PARSE_WARNING,
   2921 				     "Shell command needs a leading tab");
   2922 			goto shellCommand;
   2923 		    }
   2924 		}
   2925 	    }
   2926 #endif
   2927 	    FinishDependencyGroup();
   2928 
   2929 	    /*
   2930 	     * For some reason - probably to make the parser impossible -
   2931 	     * a ';' can be used to separate commands from dependencies.
   2932 	     * Attempt to avoid ';' inside substitution patterns.
   2933 	     */
   2934 	    {
   2935 		int level = 0;
   2936 
   2937 		for (cp = line; *cp != 0; cp++) {
   2938 		    if (*cp == '\\' && cp[1] != 0) {
   2939 			cp++;
   2940 			continue;
   2941 		    }
   2942 		    if (*cp == '$' &&
   2943 			(cp[1] == '(' || cp[1] == '{')) {
   2944 			level++;
   2945 			continue;
   2946 		    }
   2947 		    if (level > 0) {
   2948 			if (*cp == ')' || *cp == '}') {
   2949 			    level--;
   2950 			    continue;
   2951 			}
   2952 		    } else if (*cp == ';') {
   2953 			break;
   2954 		    }
   2955 		}
   2956 	    }
   2957 	    if (*cp != 0)
   2958 		/* Terminate the dependency list at the ';' */
   2959 		*cp++ = 0;
   2960 	    else
   2961 		cp = NULL;
   2962 
   2963 	    /*
   2964 	     * We now know it's a dependency line so it needs to have all
   2965 	     * variables expanded before being parsed.
   2966 	     *
   2967 	     * XXX: Ideally the dependency line would first be split into
   2968 	     * its left-hand side, dependency operator and right-hand side,
   2969 	     * and then each side would be expanded on its own.  This would
   2970 	     * allow for the left-hand side to allow only defined variables
   2971 	     * and to allow variables on the right-hand side to be undefined
   2972 	     * as well.
   2973 	     *
   2974 	     * Parsing the line first would also prevent that targets
   2975 	     * generated from variable expressions are interpreted as the
   2976 	     * dependency operator, such as in "target${:U:} middle: source",
   2977 	     * in which the middle is interpreted as a source, not a target.
   2978 	     */
   2979 	    {
   2980 	        /* In lint mode, allow undefined variables to appear in
   2981 	         * dependency lines.
   2982 	         *
   2983 	         * Ideally, only the right-hand side would allow undefined
   2984 	         * variables since it is common to have no dependencies.
   2985 	         * Having undefined variables on the left-hand side is more
   2986 	         * unusual though.  Since both sides are expanded in a single
   2987 	         * pass, there is not much choice what to do here.
   2988 	         *
   2989 	         * In normal mode, it does not matter whether undefined
   2990 	         * variables are allowed or not since as of 2020-09-14,
   2991 	         * Var_Parse does not print any parse errors in such a case.
   2992 	         * It simply returns the special empty string var_Error,
   2993 	         * which cannot be detected in the result of Var_Subst. */
   2994 		VarEvalFlags eflags = DEBUG(LINT)
   2995 				      ? VARE_WANTRES
   2996 				      : VARE_UNDEFERR|VARE_WANTRES;
   2997 		(void)Var_Subst(line, VAR_CMD, eflags, &line);
   2998 		/* TODO: handle errors */
   2999 	    }
   3000 
   3001 	    /* Need a fresh list for the target nodes */
   3002 	    if (targets != NULL)
   3003 		Lst_Free(targets);
   3004 	    targets = Lst_Init();
   3005 
   3006 	    ParseDoDependency(line);
   3007 	    free(line);
   3008 
   3009 	    /* If there were commands after a ';', add them now */
   3010 	    if (cp != NULL) {
   3011 		goto shellCommand;
   3012 	    }
   3013 	}
   3014 	/*
   3015 	 * Reached EOF, but it may be just EOF of an include file...
   3016 	 */
   3017     } while (ParseEOF() == CONTINUE);
   3018 
   3019     FinishDependencyGroup();
   3020 
   3021     if (fatals) {
   3022 	(void)fflush(stdout);
   3023 	(void)fprintf(stderr,
   3024 	    "%s: Fatal errors encountered -- cannot continue",
   3025 	    progname);
   3026 	PrintOnError(NULL, NULL);
   3027 	exit(1);
   3028     }
   3029 }
   3030 
   3031 /*-
   3032  *---------------------------------------------------------------------
   3033  * Parse_Init --
   3034  *	initialize the parsing module
   3035  *
   3036  * Results:
   3037  *	none
   3038  *
   3039  * Side Effects:
   3040  *	the parseIncPath list is initialized...
   3041  *---------------------------------------------------------------------
   3042  */
   3043 void
   3044 Parse_Init(void)
   3045 {
   3046     mainNode = NULL;
   3047     parseIncPath = Lst_Init();
   3048     sysIncPath = Lst_Init();
   3049     defIncPath = Lst_Init();
   3050     Stack_Init(&includes);
   3051 #ifdef CLEANUP
   3052     targCmds = Lst_Init();
   3053 #endif
   3054 }
   3055 
   3056 void
   3057 Parse_End(void)
   3058 {
   3059 #ifdef CLEANUP
   3060     Lst_Destroy(targCmds, free);
   3061     assert(targets == NULL);
   3062     Lst_Destroy(defIncPath, Dir_Destroy);
   3063     Lst_Destroy(sysIncPath, Dir_Destroy);
   3064     Lst_Destroy(parseIncPath, Dir_Destroy);
   3065     assert(Stack_IsEmpty(&includes));
   3066     Stack_Done(&includes);
   3067 #endif
   3068 }
   3069 
   3070 
   3071 /*-
   3072  *-----------------------------------------------------------------------
   3073  * Parse_MainName --
   3074  *	Return a Lst of the main target to create for main()'s sake. If
   3075  *	no such target exists, we Punt with an obnoxious error message.
   3076  *
   3077  * Results:
   3078  *	A Lst of the single node to create.
   3079  *
   3080  * Side Effects:
   3081  *	None.
   3082  *
   3083  *-----------------------------------------------------------------------
   3084  */
   3085 GNodeList *
   3086 Parse_MainName(void)
   3087 {
   3088     GNodeList *mainList;
   3089 
   3090     mainList = Lst_Init();
   3091 
   3092     if (mainNode == NULL) {
   3093 	Punt("no target to make.");
   3094 	/*NOTREACHED*/
   3095     } else if (mainNode->type & OP_DOUBLEDEP) {
   3096 	Lst_Append(mainList, mainNode);
   3097 	Lst_AppendAll(mainList, mainNode->cohorts);
   3098     }
   3099     else
   3100 	Lst_Append(mainList, mainNode);
   3101     Var_Append(".TARGETS", mainNode->name, VAR_GLOBAL);
   3102     return mainList;
   3103 }
   3104