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parse.c revision 1.440
      1 /*	$NetBSD: parse.c,v 1.440 2020/11/14 16:09:08 rillig Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1988, 1989, 1990, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * Adam de Boor.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. Neither the name of the University nor the names of its contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 /*
     36  * Copyright (c) 1989 by Berkeley Softworks
     37  * All rights reserved.
     38  *
     39  * This code is derived from software contributed to Berkeley by
     40  * Adam de Boor.
     41  *
     42  * Redistribution and use in source and binary forms, with or without
     43  * modification, are permitted provided that the following conditions
     44  * are met:
     45  * 1. Redistributions of source code must retain the above copyright
     46  *    notice, this list of conditions and the following disclaimer.
     47  * 2. Redistributions in binary form must reproduce the above copyright
     48  *    notice, this list of conditions and the following disclaimer in the
     49  *    documentation and/or other materials provided with the distribution.
     50  * 3. All advertising materials mentioning features or use of this software
     51  *    must display the following acknowledgement:
     52  *	This product includes software developed by the University of
     53  *	California, Berkeley and its contributors.
     54  * 4. Neither the name of the University nor the names of its contributors
     55  *    may be used to endorse or promote products derived from this software
     56  *    without specific prior written permission.
     57  *
     58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     68  * SUCH DAMAGE.
     69  */
     70 
     71 /*
     72  * Parsing of makefiles.
     73  *
     74  * Parse_File is the main entry point and controls most of the other
     75  * functions in this module.
     76  *
     77  * The directories for the .include "..." directive are kept in
     78  * 'parseIncPath', while those for .include <...> are kept in 'sysIncPath'.
     79  * The targets currently being defined are kept in 'targets'.
     80  *
     81  * Interface:
     82  *	Parse_Init	Initialize the module
     83  *
     84  *	Parse_End	Clean up the module
     85  *
     86  *	Parse_File	Parse a top-level makefile.  Included files are
     87  *			handled by Parse_include_file though.
     88  *
     89  *	Parse_IsVar	Return TRUE if the given line is a variable
     90  *			assignment. Used by MainParseArgs to determine if
     91  *			an argument is a target or a variable assignment.
     92  *			Used internally for pretty much the same thing.
     93  *
     94  *	Parse_Error	Report a parse error, a warning or an informational
     95  *			message.
     96  *
     97  *	Parse_MainName	Returns a list of the main target to create.
     98  */
     99 
    100 #include <sys/types.h>
    101 #include <sys/mman.h>
    102 #include <sys/stat.h>
    103 #include <errno.h>
    104 #include <stdarg.h>
    105 #include <stdint.h>
    106 
    107 #ifndef MAP_FILE
    108 #define MAP_FILE 0
    109 #endif
    110 #ifndef MAP_COPY
    111 #define MAP_COPY MAP_PRIVATE
    112 #endif
    113 
    114 #include "make.h"
    115 #include "dir.h"
    116 #include "job.h"
    117 #include "pathnames.h"
    118 
    119 /*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
    120 MAKE_RCSID("$NetBSD: parse.c,v 1.440 2020/11/14 16:09:08 rillig Exp $");
    121 
    122 /* types and constants */
    123 
    124 /*
    125  * Structure for a file being read ("included file")
    126  */
    127 typedef struct IFile {
    128     char *fname;		/* name of file (relative? absolute?) */
    129     Boolean fromForLoop;	/* simulated .include by the .for loop */
    130     int lineno;			/* current line number in file */
    131     int first_lineno;		/* line number of start of text */
    132     unsigned int cond_depth;	/* 'if' nesting when file opened */
    133     Boolean depending;		/* state of doing_depend on EOF */
    134 
    135     /* The buffer from which the file's content is read. */
    136     char *buf_freeIt;
    137     char *buf_ptr;		/* next char to be read */
    138     char *buf_end;
    139 
    140     char *(*nextbuf)(void *, size_t *); /* Function to get more data */
    141     void *nextbuf_arg;		/* Opaque arg for nextbuf() */
    142     struct loadedfile *lf;	/* loadedfile object, if any */
    143 } IFile;
    144 
    145 /*
    146  * Tokens for target attributes
    147  */
    148 typedef enum ParseSpecial {
    149     SP_ATTRIBUTE,	/* Generic attribute */
    150     SP_BEGIN,		/* .BEGIN */
    151     SP_DEFAULT,		/* .DEFAULT */
    152     SP_DELETE_ON_ERROR,	/* .DELETE_ON_ERROR */
    153     SP_END,		/* .END */
    154     SP_ERROR,		/* .ERROR */
    155     SP_IGNORE,		/* .IGNORE */
    156     SP_INCLUDES,	/* .INCLUDES; not mentioned in the manual page */
    157     SP_INTERRUPT,	/* .INTERRUPT */
    158     SP_LIBS,		/* .LIBS; not mentioned in the manual page */
    159     SP_MAIN,		/* .MAIN and we don't have anything user-specified to
    160 			 * make */
    161     SP_META,		/* .META */
    162     SP_MFLAGS,		/* .MFLAGS or .MAKEFLAGS */
    163     SP_NOMETA,		/* .NOMETA */
    164     SP_NOMETA_CMP,	/* .NOMETA_CMP */
    165     SP_NOPATH,		/* .NOPATH */
    166     SP_NOT,		/* Not special */
    167     SP_NOTPARALLEL,	/* .NOTPARALLEL or .NO_PARALLEL */
    168     SP_NULL,		/* .NULL; not mentioned in the manual page */
    169     SP_OBJDIR,		/* .OBJDIR */
    170     SP_ORDER,		/* .ORDER */
    171     SP_PARALLEL,	/* .PARALLEL; not mentioned in the manual page */
    172     SP_PATH,		/* .PATH or .PATH.suffix */
    173     SP_PHONY,		/* .PHONY */
    174 #ifdef POSIX
    175     SP_POSIX,		/* .POSIX; not mentioned in the manual page */
    176 #endif
    177     SP_PRECIOUS,	/* .PRECIOUS */
    178     SP_SHELL,		/* .SHELL */
    179     SP_SILENT,		/* .SILENT */
    180     SP_SINGLESHELL,	/* .SINGLESHELL; not mentioned in the manual page */
    181     SP_STALE,		/* .STALE */
    182     SP_SUFFIXES,	/* .SUFFIXES */
    183     SP_WAIT		/* .WAIT */
    184 } ParseSpecial;
    185 
    186 typedef List SearchPathList;
    187 typedef ListNode SearchPathListNode;
    188 
    189 /* result data */
    190 
    191 /*
    192  * The main target to create. This is the first target on the first
    193  * dependency line in the first makefile.
    194  */
    195 static GNode *mainNode;
    196 
    197 /* eval state */
    198 
    199 /* During parsing, the targets from the left-hand side of the currently
    200  * active dependency line, or NULL if the current line does not belong to a
    201  * dependency line, for example because it is a variable assignment.
    202  *
    203  * See unit-tests/deptgt.mk, keyword "parse.c:targets". */
    204 static GNodeList *targets;
    205 
    206 #ifdef CLEANUP
    207 /* All shell commands for all targets, in no particular order and possibly
    208  * with duplicates.  Kept in a separate list since the commands from .USE or
    209  * .USEBEFORE nodes are shared with other GNodes, thereby giving up the
    210  * easily understandable ownership over the allocated strings. */
    211 static StringList *targCmds;
    212 #endif
    213 
    214 /*
    215  * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
    216  * seen, then set to each successive source on the line.
    217  */
    218 static GNode *order_pred;
    219 
    220 /* parser state */
    221 
    222 /* number of fatal errors */
    223 static int fatals = 0;
    224 
    225 /*
    226  * Variables for doing includes
    227  */
    228 
    229 /* The include chain of makefiles.  At the bottom is the top-level makefile
    230  * from the command line, and on top of that, there are the included files or
    231  * .for loops, up to and including the current file.
    232  *
    233  * This data could be used to print stack traces on parse errors.  As of
    234  * 2020-09-14, this is not done though.  It seems quite simple to print the
    235  * tuples (fname:lineno:fromForLoop), from top to bottom.  This simple idea is
    236  * made complicated by the fact that the .for loops also use this stack for
    237  * storing information.
    238  *
    239  * The lineno fields of the IFiles with fromForLoop == TRUE look confusing,
    240  * which is demonstrated by the test 'include-main.mk'.  They seem sorted
    241  * backwards since they tell the number of completely parsed lines, which for
    242  * a .for loop is right after the terminating .endfor.  To compensate for this
    243  * confusion, there is another field first_lineno pointing at the start of the
    244  * .for loop, 1-based for human consumption.
    245  *
    246  * To make the stack trace intuitive, the entry below the first .for loop must
    247  * be ignored completely since neither its lineno nor its first_lineno is
    248  * useful.  Instead, the topmost of each chain of .for loop needs to be
    249  * printed twice, once with its first_lineno and once with its lineno.
    250  *
    251  * As of 2020-10-28, using the above rules, the stack trace for the .info line
    252  * in include-subsub.mk would be:
    253  *
    254  *	includes[5]:	include-subsub.mk:4
    255  *			(lineno, from an .include)
    256  *	includes[4]:	include-sub.mk:32
    257  *			(lineno, from a .for loop below an .include)
    258  *	includes[4]:	include-sub.mk:31
    259  *			(first_lineno, from a .for loop, lineno == 32)
    260  *	includes[3]:	include-sub.mk:30
    261  *			(first_lineno, from a .for loop, lineno == 33)
    262  *	includes[2]:	include-sub.mk:29
    263  *			(first_lineno, from a .for loop, lineno == 34)
    264  *	includes[1]:	include-sub.mk:35
    265  *			(not printed since it is below a .for loop)
    266  *	includes[0]:	include-main.mk:27
    267  */
    268 static Vector /* of IFile */ includes;
    269 
    270 static IFile *
    271 GetInclude(size_t i)
    272 {
    273     return Vector_Get(&includes, i);
    274 }
    275 
    276 /* The file that is currently being read. */
    277 static IFile *
    278 CurFile(void)
    279 {
    280     return GetInclude(includes.len - 1);
    281 }
    282 
    283 /* include paths */
    284 SearchPath *parseIncPath;	/* dirs for "..." includes */
    285 SearchPath *sysIncPath;		/* dirs for <...> includes */
    286 SearchPath *defSysIncPath;	/* default for sysIncPath */
    287 
    288 /* parser tables */
    289 
    290 /*
    291  * The parseKeywords table is searched using binary search when deciding
    292  * if a target or source is special. The 'spec' field is the ParseSpecial
    293  * type of the keyword (SP_NOT if the keyword isn't special as a target) while
    294  * the 'op' field is the operator to apply to the list of targets if the
    295  * keyword is used as a source ("0" if the keyword isn't special as a source)
    296  */
    297 static const struct {
    298     const char   *name;		/* Name of keyword */
    299     ParseSpecial  spec;		/* Type when used as a target */
    300     GNodeType	  op;		/* Operator when used as a source */
    301 } parseKeywords[] = {
    302     { ".BEGIN",		SP_BEGIN,	0 },
    303     { ".DEFAULT",	SP_DEFAULT,	0 },
    304     { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, 0 },
    305     { ".END",		SP_END,		0 },
    306     { ".ERROR",		SP_ERROR,	0 },
    307     { ".EXEC",		SP_ATTRIBUTE,	OP_EXEC },
    308     { ".IGNORE",	SP_IGNORE,	OP_IGNORE },
    309     { ".INCLUDES",	SP_INCLUDES,	0 },
    310     { ".INTERRUPT",	SP_INTERRUPT,	0 },
    311     { ".INVISIBLE",	SP_ATTRIBUTE,	OP_INVISIBLE },
    312     { ".JOIN",		SP_ATTRIBUTE,	OP_JOIN },
    313     { ".LIBS",		SP_LIBS,	0 },
    314     { ".MADE",		SP_ATTRIBUTE,	OP_MADE },
    315     { ".MAIN",		SP_MAIN,	0 },
    316     { ".MAKE",		SP_ATTRIBUTE,	OP_MAKE },
    317     { ".MAKEFLAGS",	SP_MFLAGS,	0 },
    318     { ".META",		SP_META,	OP_META },
    319     { ".MFLAGS",	SP_MFLAGS,	0 },
    320     { ".NOMETA",	SP_NOMETA,	OP_NOMETA },
    321     { ".NOMETA_CMP",	SP_NOMETA_CMP,	OP_NOMETA_CMP },
    322     { ".NOPATH",	SP_NOPATH,	OP_NOPATH },
    323     { ".NOTMAIN",	SP_ATTRIBUTE,	OP_NOTMAIN },
    324     { ".NOTPARALLEL",	SP_NOTPARALLEL,	0 },
    325     { ".NO_PARALLEL",	SP_NOTPARALLEL,	0 },
    326     { ".NULL",		SP_NULL,	0 },
    327     { ".OBJDIR",	SP_OBJDIR,	0 },
    328     { ".OPTIONAL",	SP_ATTRIBUTE,	OP_OPTIONAL },
    329     { ".ORDER",		SP_ORDER,	0 },
    330     { ".PARALLEL",	SP_PARALLEL,	0 },
    331     { ".PATH",		SP_PATH,	0 },
    332     { ".PHONY",		SP_PHONY,	OP_PHONY },
    333 #ifdef POSIX
    334     { ".POSIX",		SP_POSIX,	0 },
    335 #endif
    336     { ".PRECIOUS",	SP_PRECIOUS,	OP_PRECIOUS },
    337     { ".RECURSIVE",	SP_ATTRIBUTE,	OP_MAKE },
    338     { ".SHELL",		SP_SHELL,	0 },
    339     { ".SILENT",	SP_SILENT,	OP_SILENT },
    340     { ".SINGLESHELL",	SP_SINGLESHELL,	0 },
    341     { ".STALE",		SP_STALE,	0 },
    342     { ".SUFFIXES",	SP_SUFFIXES,	0 },
    343     { ".USE",		SP_ATTRIBUTE,	OP_USE },
    344     { ".USEBEFORE",	SP_ATTRIBUTE,	OP_USEBEFORE },
    345     { ".WAIT",		SP_WAIT,	0 },
    346 };
    347 
    348 /* file loader */
    349 
    350 struct loadedfile {
    351 	const char *path;		/* name, for error reports */
    352 	char *buf;			/* contents buffer */
    353 	size_t len;			/* length of contents */
    354 	size_t maplen;			/* length of mmap area, or 0 */
    355 	Boolean used;			/* XXX: have we used the data yet */
    356 };
    357 
    358 static struct loadedfile *
    359 loadedfile_create(const char *path)
    360 {
    361 	struct loadedfile *lf;
    362 
    363 	lf = bmake_malloc(sizeof *lf);
    364 	lf->path = path == NULL ? "(stdin)" : path;
    365 	lf->buf = NULL;
    366 	lf->len = 0;
    367 	lf->maplen = 0;
    368 	lf->used = FALSE;
    369 	return lf;
    370 }
    371 
    372 static void
    373 loadedfile_destroy(struct loadedfile *lf)
    374 {
    375 	if (lf->buf != NULL) {
    376 		if (lf->maplen > 0)
    377 			munmap(lf->buf, lf->maplen);
    378 		else
    379 			free(lf->buf);
    380 	}
    381 	free(lf);
    382 }
    383 
    384 /*
    385  * nextbuf() operation for loadedfile, as needed by the weird and twisted
    386  * logic below. Once that's cleaned up, we can get rid of lf->used...
    387  */
    388 static char *
    389 loadedfile_nextbuf(void *x, size_t *len)
    390 {
    391 	struct loadedfile *lf = x;
    392 
    393 	if (lf->used)
    394 		return NULL;
    395 
    396 	lf->used = TRUE;
    397 	*len = lf->len;
    398 	return lf->buf;
    399 }
    400 
    401 /*
    402  * Try to get the size of a file.
    403  */
    404 static Boolean
    405 load_getsize(int fd, size_t *ret)
    406 {
    407 	struct stat st;
    408 
    409 	if (fstat(fd, &st) < 0)
    410 		return FALSE;
    411 
    412 	if (!S_ISREG(st.st_mode))
    413 		return FALSE;
    414 
    415 	/*
    416 	 * st_size is an off_t, which is 64 bits signed; *ret is
    417 	 * size_t, which might be 32 bits unsigned or 64 bits
    418 	 * unsigned. Rather than being elaborate, just punt on
    419 	 * files that are more than 2^31 bytes. We should never
    420 	 * see a makefile that size in practice...
    421 	 *
    422 	 * While we're at it reject negative sizes too, just in case.
    423 	 */
    424 	if (st.st_size < 0 || st.st_size > 0x7fffffff)
    425 		return FALSE;
    426 
    427 	*ret = (size_t)st.st_size;
    428 	return TRUE;
    429 }
    430 
    431 static Boolean
    432 loadedfile_mmap(struct loadedfile *lf, int fd)
    433 {
    434 	static unsigned long pagesize = 0;
    435 
    436 	if (!load_getsize(fd, &lf->len))
    437 		return FALSE;
    438 
    439 	/* found a size, try mmap */
    440 	if (pagesize == 0)
    441 		pagesize = (unsigned long)sysconf(_SC_PAGESIZE);
    442 	if (pagesize == 0 || pagesize == (unsigned long)-1)
    443 		pagesize = 0x1000;
    444 
    445 	/* round size up to a page */
    446 	lf->maplen = pagesize * ((lf->len + pagesize - 1) / pagesize);
    447 
    448 	/*
    449 	 * XXX hack for dealing with empty files; remove when
    450 	 * we're no longer limited by interfacing to the old
    451 	 * logic elsewhere in this file.
    452 	 */
    453 	if (lf->maplen == 0)
    454 		lf->maplen = pagesize;
    455 
    456 	/*
    457 	 * FUTURE: remove PROT_WRITE when the parser no longer
    458 	 * needs to scribble on the input.
    459 	 */
    460 	lf->buf = mmap(NULL, lf->maplen, PROT_READ|PROT_WRITE,
    461 		       MAP_FILE|MAP_COPY, fd, 0);
    462 	if (lf->buf == MAP_FAILED)
    463 		return FALSE;
    464 
    465 	if (lf->len == lf->maplen && lf->buf[lf->len - 1] != '\n') {
    466 		char *b = bmake_malloc(lf->len + 1);
    467 		b[lf->len] = '\n';
    468 		memcpy(b, lf->buf, lf->len++);
    469 		munmap(lf->buf, lf->maplen);
    470 		lf->maplen = 0;
    471 		lf->buf = b;
    472 	}
    473 
    474 	return TRUE;
    475 }
    476 
    477 /*
    478  * Read in a file.
    479  *
    480  * Until the path search logic can be moved under here instead of
    481  * being in the caller in another source file, we need to have the fd
    482  * passed in already open. Bleh.
    483  *
    484  * If the path is NULL, use stdin.
    485  */
    486 static struct loadedfile *
    487 loadfile(const char *path, int fd)
    488 {
    489 	struct loadedfile *lf;
    490 	ssize_t result;
    491 	size_t bufpos;
    492 
    493 	lf = loadedfile_create(path);
    494 
    495 	if (path == NULL) {
    496 		assert(fd == -1);
    497 		fd = STDIN_FILENO;
    498 	} else {
    499 #if 0 /* notyet */
    500 		fd = open(path, O_RDONLY);
    501 		if (fd < 0) {
    502 			...
    503 			Error("%s: %s", path, strerror(errno));
    504 			exit(1);
    505 		}
    506 #endif
    507 	}
    508 
    509 	if (loadedfile_mmap(lf, fd))
    510 		goto done;
    511 
    512 	/* cannot mmap; load the traditional way */
    513 
    514 	lf->maplen = 0;
    515 	lf->len = 1024;
    516 	lf->buf = bmake_malloc(lf->len);
    517 
    518 	bufpos = 0;
    519 	for (;;) {
    520 		assert(bufpos <= lf->len);
    521 		if (bufpos == lf->len) {
    522 			if (lf->len > SIZE_MAX/2) {
    523 				errno = EFBIG;
    524 				Error("%s: file too large", path);
    525 				exit(1);
    526 			}
    527 			lf->len *= 2;
    528 			lf->buf = bmake_realloc(lf->buf, lf->len);
    529 		}
    530 		assert(bufpos < lf->len);
    531 		result = read(fd, lf->buf + bufpos, lf->len - bufpos);
    532 		if (result < 0) {
    533 			Error("%s: read error: %s", path, strerror(errno));
    534 			exit(1);
    535 		}
    536 		if (result == 0)
    537 			break;
    538 
    539 		bufpos += (size_t)result;
    540 	}
    541 	assert(bufpos <= lf->len);
    542 	lf->len = bufpos;
    543 
    544 	/* truncate malloc region to actual length (maybe not useful) */
    545 	if (lf->len > 0) {
    546 		/* as for mmap case, ensure trailing \n */
    547 		if (lf->buf[lf->len - 1] != '\n')
    548 			lf->len++;
    549 		lf->buf = bmake_realloc(lf->buf, lf->len);
    550 		lf->buf[lf->len - 1] = '\n';
    551 	}
    552 
    553 done:
    554 	if (path != NULL)
    555 		close(fd);
    556 
    557 	return lf;
    558 }
    559 
    560 /* old code */
    561 
    562 /* Check if the current character is escaped on the current line. */
    563 static Boolean
    564 ParseIsEscaped(const char *line, const char *c)
    565 {
    566     Boolean active = FALSE;
    567     for (;;) {
    568 	if (line == c)
    569 	    return active;
    570 	if (*--c != '\\')
    571 	    return active;
    572 	active = !active;
    573     }
    574 }
    575 
    576 /* Add the filename and lineno to the GNode so that we remember where it
    577  * was first defined. */
    578 static void
    579 ParseMark(GNode *gn)
    580 {
    581     IFile *curFile = CurFile();
    582     gn->fname = curFile->fname;
    583     gn->lineno = curFile->lineno;
    584 }
    585 
    586 /* Look in the table of keywords for one matching the given string.
    587  * Return the index of the keyword, or -1 if it isn't there. */
    588 static int
    589 ParseFindKeyword(const char *str)
    590 {
    591     int start = 0;
    592     int end = sizeof parseKeywords / sizeof parseKeywords[0] - 1;
    593 
    594     do {
    595 	int cur = start + (end - start) / 2;
    596 	int diff = strcmp(str, parseKeywords[cur].name);
    597 
    598 	if (diff == 0)
    599 	    return cur;
    600 	if (diff < 0)
    601 	    end = cur - 1;
    602 	else
    603 	    start = cur + 1;
    604     } while (start <= end);
    605 
    606     return -1;
    607 }
    608 
    609 static void
    610 PrintLocation(FILE *f, const char *filename, size_t lineno)
    611 {
    612 	char dirbuf[MAXPATHLEN+1];
    613 	const char *dir, *base;
    614 	void *dir_freeIt, *base_freeIt;
    615 
    616 	if (*filename == '/' || strcmp(filename, "(stdin)") == 0) {
    617 		(void)fprintf(f, "\"%s\" line %zu: ", filename, lineno);
    618 		return;
    619 	}
    620 
    621 	/* Find out which makefile is the culprit.
    622 	 * We try ${.PARSEDIR} and apply realpath(3) if not absolute. */
    623 
    624 	dir = Var_Value(".PARSEDIR", VAR_GLOBAL, &dir_freeIt);
    625 	if (dir == NULL)
    626 		dir = ".";
    627 	if (*dir != '/')
    628 		dir = realpath(dir, dirbuf);
    629 
    630 	base = Var_Value(".PARSEFILE", VAR_GLOBAL, &base_freeIt);
    631 	if (base == NULL) {
    632 		const char *slash = strrchr(filename, '/');
    633 		base = slash != NULL ? slash + 1 : filename;
    634 	}
    635 
    636 	(void)fprintf(f, "\"%s/%s\" line %zu: ", dir, base, lineno);
    637 	bmake_free(base_freeIt);
    638 	bmake_free(dir_freeIt);
    639 }
    640 
    641 /* Print a parse error message, including location information.
    642  *
    643  * Increment "fatals" if the level is PARSE_FATAL, and continue parsing
    644  * until the end of the current top-level makefile, then exit (see
    645  * Parse_File). */
    646 static void
    647 ParseVErrorInternal(FILE *f, const char *cfname, size_t clineno,
    648 		    ParseErrorLevel type, const char *fmt, va_list ap)
    649 {
    650 	static Boolean fatal_warning_error_printed = FALSE;
    651 
    652 	(void)fprintf(f, "%s: ", progname);
    653 
    654 	if (cfname != NULL)
    655 		PrintLocation(f, cfname, clineno);
    656 	if (type == PARSE_WARNING)
    657 		(void)fprintf(f, "warning: ");
    658 	(void)vfprintf(f, fmt, ap);
    659 	(void)fprintf(f, "\n");
    660 	(void)fflush(f);
    661 
    662 	if (type == PARSE_INFO)
    663 		return;
    664 	if (type == PARSE_FATAL || opts.parseWarnFatal)
    665 		fatals++;
    666 	if (opts.parseWarnFatal && !fatal_warning_error_printed) {
    667 		Error("parsing warnings being treated as errors");
    668 		fatal_warning_error_printed = TRUE;
    669 	}
    670 }
    671 
    672 static void
    673 ParseErrorInternal(const char *cfname, size_t clineno, ParseErrorLevel type,
    674 		   const char *fmt, ...)
    675 {
    676 	va_list ap;
    677 
    678 	va_start(ap, fmt);
    679 	(void)fflush(stdout);
    680 	ParseVErrorInternal(stderr, cfname, clineno, type, fmt, ap);
    681 	va_end(ap);
    682 
    683 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
    684 		va_start(ap, fmt);
    685 		ParseVErrorInternal(opts.debug_file, cfname, clineno, type,
    686 				    fmt, ap);
    687 		va_end(ap);
    688 	}
    689 }
    690 
    691 /* External interface to ParseErrorInternal; uses the default filename and
    692  * line number.
    693  *
    694  * Fmt is given without a trailing newline. */
    695 void
    696 Parse_Error(ParseErrorLevel type, const char *fmt, ...)
    697 {
    698 	va_list ap;
    699 	const char *fname;
    700 	size_t lineno;
    701 
    702 	if (includes.len == 0) {
    703 		fname = NULL;
    704 		lineno = 0;
    705 	} else {
    706 		IFile *curFile = CurFile();
    707 		fname = curFile->fname;
    708 		lineno = (size_t)curFile->lineno;
    709 	}
    710 
    711 	va_start(ap, fmt);
    712 	(void)fflush(stdout);
    713 	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
    714 	va_end(ap);
    715 
    716 	if (opts.debug_file != stderr && opts.debug_file != stdout) {
    717 		va_start(ap, fmt);
    718 		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
    719 				    fmt, ap);
    720 		va_end(ap);
    721 	}
    722 }
    723 
    724 
    725 /* Parse a .info .warning or .error directive.
    726  *
    727  * The input is the line minus the ".".  We substitute variables, print the
    728  * message and exit(1) (for .error) or just print a warning if the directive
    729  * is malformed.
    730  */
    731 static Boolean
    732 ParseMessage(const char *directive)
    733 {
    734     const char *p = directive;
    735     int mtype = *p == 'i' ? PARSE_INFO :
    736 		*p == 'w' ? PARSE_WARNING : PARSE_FATAL;
    737     char *arg;
    738 
    739     while (ch_isalpha(*p))
    740 	p++;
    741     if (!ch_isspace(*p))
    742 	return FALSE;		/* missing argument */
    743 
    744     cpp_skip_whitespace(&p);
    745     (void)Var_Subst(p, VAR_CMDLINE, VARE_WANTRES, &arg);
    746     /* TODO: handle errors */
    747 
    748     Parse_Error(mtype, "%s", arg);
    749     free(arg);
    750 
    751     if (mtype == PARSE_FATAL) {
    752 	PrintOnError(NULL, NULL);
    753 	exit(1);
    754     }
    755     return TRUE;
    756 }
    757 
    758 /* Add the child to the parent's children.
    759  *
    760  * Additionally, add the parent to the child's parents, but only if the
    761  * target is not special.  An example for such a special target is .END,
    762  * which does not need to be informed once the child target has been made. */
    763 static void
    764 LinkSource(GNode *pgn, GNode *cgn, Boolean isSpecial)
    765 {
    766     if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(pgn->cohorts))
    767 	pgn = pgn->cohorts->last->datum;
    768 
    769     Lst_Append(pgn->children, cgn);
    770     pgn->unmade++;
    771 
    772     /* Special targets like .END don't need any children. */
    773     if (!isSpecial)
    774 	Lst_Append(cgn->parents, pgn);
    775 
    776     if (DEBUG(PARSE)) {
    777 	debug_printf("# %s: added child %s - %s\n",
    778 		     __func__, pgn->name, cgn->name);
    779 	Targ_PrintNode(pgn, 0);
    780 	Targ_PrintNode(cgn, 0);
    781     }
    782 }
    783 
    784 /* Add the node to each target from the current dependency group. */
    785 static void
    786 LinkToTargets(GNode *gn, Boolean isSpecial)
    787 {
    788     GNodeListNode *ln;
    789     for (ln = targets->first; ln != NULL; ln = ln->next)
    790 	LinkSource(ln->datum, gn, isSpecial);
    791 }
    792 
    793 static Boolean
    794 TryApplyDependencyOperator(GNode *gn, GNodeType op)
    795 {
    796     /*
    797      * If the node occurred on the left-hand side of a dependency and the
    798      * operator also defines a dependency, they must match.
    799      */
    800     if ((op & OP_OPMASK) && (gn->type & OP_OPMASK) &&
    801 	((op & OP_OPMASK) != (gn->type & OP_OPMASK)))
    802     {
    803 	Parse_Error(PARSE_FATAL, "Inconsistent operator for %s", gn->name);
    804 	return FALSE;
    805     }
    806 
    807     if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
    808 	/*
    809 	 * If the node was the object of a :: operator, we need to create a
    810 	 * new instance of it for the children and commands on this dependency
    811 	 * line. The new instance is placed on the 'cohorts' list of the
    812 	 * initial one (note the initial one is not on its own cohorts list)
    813 	 * and the new instance is linked to all parents of the initial
    814 	 * instance.
    815 	 */
    816 	GNode *cohort;
    817 
    818 	/*
    819 	 * Propagate copied bits to the initial node.  They'll be propagated
    820 	 * back to the rest of the cohorts later.
    821 	 */
    822 	gn->type |= op & ~OP_OPMASK;
    823 
    824 	cohort = Targ_NewInternalNode(gn->name);
    825 	if (doing_depend)
    826 	    ParseMark(cohort);
    827 	/*
    828 	 * Make the cohort invisible as well to avoid duplicating it into
    829 	 * other variables. True, parents of this target won't tend to do
    830 	 * anything with their local variables, but better safe than
    831 	 * sorry. (I think this is pointless now, since the relevant list
    832 	 * traversals will no longer see this node anyway. -mycroft)
    833 	 */
    834 	cohort->type = op | OP_INVISIBLE;
    835 	Lst_Append(gn->cohorts, cohort);
    836 	cohort->centurion = gn;
    837 	gn->unmade_cohorts++;
    838 	snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
    839 		 (unsigned int)gn->unmade_cohorts % 1000000);
    840     } else {
    841 	/*
    842 	 * We don't want to nuke any previous flags (whatever they were) so we
    843 	 * just OR the new operator into the old
    844 	 */
    845 	gn->type |= op;
    846     }
    847 
    848     return TRUE;
    849 }
    850 
    851 static void
    852 ApplyDependencyOperator(GNodeType op)
    853 {
    854     GNodeListNode *ln;
    855     for (ln = targets->first; ln != NULL; ln = ln->next)
    856 	if (!TryApplyDependencyOperator(ln->datum, op))
    857 	    break;
    858 }
    859 
    860 static Boolean
    861 ParseDoSrcKeyword(const char *src, ParseSpecial specType)
    862 {
    863     static int wait_number = 0;
    864     char wait_src[16];
    865     GNode *gn;
    866 
    867     if (*src == '.' && ch_isupper(src[1])) {
    868 	int keywd = ParseFindKeyword(src);
    869 	if (keywd != -1) {
    870 	    int op = parseKeywords[keywd].op;
    871 	    if (op != 0) {
    872 		ApplyDependencyOperator(op);
    873 		return TRUE;
    874 	    }
    875 	    if (parseKeywords[keywd].spec == SP_WAIT) {
    876 		/*
    877 		 * We add a .WAIT node in the dependency list.
    878 		 * After any dynamic dependencies (and filename globbing)
    879 		 * have happened, it is given a dependency on the each
    880 		 * previous child back to and previous .WAIT node.
    881 		 * The next child won't be scheduled until the .WAIT node
    882 		 * is built.
    883 		 * We give each .WAIT node a unique name (mainly for diag).
    884 		 */
    885 		snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
    886 		gn = Targ_NewInternalNode(wait_src);
    887 		if (doing_depend)
    888 		    ParseMark(gn);
    889 		gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
    890 		LinkToTargets(gn, specType != SP_NOT);
    891 		return TRUE;
    892 	    }
    893 	}
    894     }
    895     return FALSE;
    896 }
    897 
    898 static void
    899 ParseDoSrcMain(const char *src)
    900 {
    901     /*
    902      * If we have noted the existence of a .MAIN, it means we need
    903      * to add the sources of said target to the list of things
    904      * to create. The string 'src' is likely to be free, so we
    905      * must make a new copy of it. Note that this will only be
    906      * invoked if the user didn't specify a target on the command
    907      * line. This is to allow #ifmake's to succeed, or something...
    908      */
    909     Lst_Append(opts.create, bmake_strdup(src));
    910     /*
    911      * Add the name to the .TARGETS variable as well, so the user can
    912      * employ that, if desired.
    913      */
    914     Var_Append(".TARGETS", src, VAR_GLOBAL);
    915 }
    916 
    917 static void
    918 ParseDoSrcOrder(const char *src)
    919 {
    920     GNode *gn;
    921     /*
    922      * Create proper predecessor/successor links between the previous
    923      * source and the current one.
    924      */
    925     gn = Targ_GetNode(src);
    926     if (doing_depend)
    927 	ParseMark(gn);
    928     if (order_pred != NULL) {
    929 	Lst_Append(order_pred->order_succ, gn);
    930 	Lst_Append(gn->order_pred, order_pred);
    931 	if (DEBUG(PARSE)) {
    932 	    debug_printf("# %s: added Order dependency %s - %s\n",
    933 			 __func__, order_pred->name, gn->name);
    934 	    Targ_PrintNode(order_pred, 0);
    935 	    Targ_PrintNode(gn, 0);
    936 	}
    937     }
    938     /*
    939      * The current source now becomes the predecessor for the next one.
    940      */
    941     order_pred = gn;
    942 }
    943 
    944 static void
    945 ParseDoSrcOther(const char *src, GNodeType tOp, ParseSpecial specType)
    946 {
    947     GNode *gn;
    948 
    949     /*
    950      * If the source is not an attribute, we need to find/create
    951      * a node for it. After that we can apply any operator to it
    952      * from a special target or link it to its parents, as
    953      * appropriate.
    954      *
    955      * In the case of a source that was the object of a :: operator,
    956      * the attribute is applied to all of its instances (as kept in
    957      * the 'cohorts' list of the node) or all the cohorts are linked
    958      * to all the targets.
    959      */
    960 
    961     /* Find/create the 'src' node and attach to all targets */
    962     gn = Targ_GetNode(src);
    963     if (doing_depend)
    964 	ParseMark(gn);
    965     if (tOp)
    966 	gn->type |= tOp;
    967     else
    968 	LinkToTargets(gn, specType != SP_NOT);
    969 }
    970 
    971 /* Given the name of a source in a dependency line, figure out if it is an
    972  * attribute (such as .SILENT) and apply it to the targets if it is. Else
    973  * decide if there is some attribute which should be applied *to* the source
    974  * because of some special target (such as .PHONY) and apply it if so.
    975  * Otherwise, make the source a child of the targets in the list 'targets'.
    976  *
    977  * Input:
    978  *	tOp		operator (if any) from special targets
    979  *	src		name of the source to handle
    980  */
    981 static void
    982 ParseDoSrc(GNodeType tOp, const char *src, ParseSpecial specType)
    983 {
    984     if (ParseDoSrcKeyword(src, specType))
    985 	return;
    986 
    987     if (specType == SP_MAIN)
    988 	ParseDoSrcMain(src);
    989     else if (specType == SP_ORDER)
    990 	ParseDoSrcOrder(src);
    991     else
    992 	ParseDoSrcOther(src, tOp, specType);
    993 }
    994 
    995 /* If we have yet to decide on a main target to make, in the absence of any
    996  * user input, we want the first target on the first dependency line that is
    997  * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made. */
    998 static void
    999 FindMainTarget(void)
   1000 {
   1001     GNodeListNode *ln;
   1002 
   1003     if (mainNode != NULL)
   1004 	return;
   1005 
   1006     for (ln = targets->first; ln != NULL; ln = ln->next) {
   1007 	GNode *gn = ln->datum;
   1008 	if (!(gn->type & OP_NOTARGET)) {
   1009 	    mainNode = gn;
   1010 	    Targ_SetMain(gn);
   1011 	    return;
   1012 	}
   1013     }
   1014 }
   1015 
   1016 /*
   1017  * We got to the end of the line while we were still looking at targets.
   1018  *
   1019  * Ending a dependency line without an operator is a Bozo no-no.  As a
   1020  * heuristic, this is also often triggered by undetected conflicts from
   1021  * cvs/rcs merges.
   1022  */
   1023 static void
   1024 ParseErrorNoDependency(const char *lstart)
   1025 {
   1026     if ((strncmp(lstart, "<<<<<<", 6) == 0) ||
   1027 	(strncmp(lstart, "======", 6) == 0) ||
   1028 	(strncmp(lstart, ">>>>>>", 6) == 0))
   1029 	Parse_Error(PARSE_FATAL,
   1030 		    "Makefile appears to contain unresolved cvs/rcs/??? merge conflicts");
   1031     else if (lstart[0] == '.') {
   1032 	const char *dirstart = lstart + 1;
   1033 	const char *dirend;
   1034 	cpp_skip_whitespace(&dirstart);
   1035 	dirend = dirstart;
   1036 	while (ch_isalnum(*dirend) || *dirend == '-')
   1037 	    dirend++;
   1038 	Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
   1039 		    (int)(dirend - dirstart), dirstart);
   1040     } else
   1041 	Parse_Error(PARSE_FATAL, "Need an operator");
   1042 }
   1043 
   1044 static void
   1045 ParseDependencyTargetWord(/*const*/ char **pp, const char *lstart)
   1046 {
   1047     /*const*/ char *cp = *pp;
   1048 
   1049     while (*cp != '\0') {
   1050 	if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' || *cp == '(') &&
   1051 	    !ParseIsEscaped(lstart, cp))
   1052 	    break;
   1053 
   1054 	if (*cp == '$') {
   1055 	    /*
   1056 	     * Must be a dynamic source (would have been expanded
   1057 	     * otherwise), so call the Var module to parse the puppy
   1058 	     * so we can safely advance beyond it...There should be
   1059 	     * no errors in this, as they would have been discovered
   1060 	     * in the initial Var_Subst and we wouldn't be here.
   1061 	     */
   1062 	    const char *nested_p = cp;
   1063 	    const char *nested_val;
   1064 	    void *freeIt;
   1065 
   1066 	    (void)Var_Parse(&nested_p, VAR_CMDLINE,
   1067 			    VARE_WANTRES | VARE_UNDEFERR, &nested_val, &freeIt);
   1068 	    /* TODO: handle errors */
   1069 	    free(freeIt);
   1070 	    cp += nested_p - cp;
   1071 	} else
   1072 	    cp++;
   1073     }
   1074 
   1075     *pp = cp;
   1076 }
   1077 
   1078 /* Handle special targets like .PATH, .DEFAULT, .BEGIN, .ORDER. */
   1079 static void
   1080 ParseDoDependencyTargetSpecial(ParseSpecial *inout_specType,
   1081 			       const char *line,
   1082 			       SearchPathList **inout_paths)
   1083 {
   1084     switch (*inout_specType) {
   1085     case SP_PATH:
   1086 	if (*inout_paths == NULL)
   1087 	    *inout_paths = Lst_New();
   1088 	Lst_Append(*inout_paths, dirSearchPath);
   1089 	break;
   1090     case SP_MAIN:
   1091 	/* Allow targets from the command line to override the .MAIN node. */
   1092 	if (!Lst_IsEmpty(opts.create))
   1093 	    *inout_specType = SP_NOT;
   1094 	break;
   1095     case SP_BEGIN:
   1096     case SP_END:
   1097     case SP_STALE:
   1098     case SP_ERROR:
   1099     case SP_INTERRUPT: {
   1100 	GNode *gn = Targ_GetNode(line);
   1101 	if (doing_depend)
   1102 	    ParseMark(gn);
   1103 	gn->type |= OP_NOTMAIN|OP_SPECIAL;
   1104 	Lst_Append(targets, gn);
   1105 	break;
   1106     }
   1107     case SP_DEFAULT: {
   1108 	/* Need to create a node to hang commands on, but we don't want it
   1109 	 * in the graph, nor do we want it to be the Main Target. We claim
   1110 	 * the node is a transformation rule to make life easier later,
   1111 	 * when we'll use Make_HandleUse to actually apply the .DEFAULT
   1112 	 * commands. */
   1113 	GNode *gn = Targ_NewGN(".DEFAULT");
   1114 	gn->type |= OP_NOTMAIN|OP_TRANSFORM;
   1115 	Lst_Append(targets, gn);
   1116 	defaultNode = gn;
   1117 	break;
   1118     }
   1119     case SP_DELETE_ON_ERROR:
   1120 	deleteOnError = TRUE;
   1121 	break;
   1122     case SP_NOTPARALLEL:
   1123 	opts.maxJobs = 1;
   1124 	break;
   1125     case SP_SINGLESHELL:
   1126 	opts.compatMake = TRUE;
   1127 	break;
   1128     case SP_ORDER:
   1129 	order_pred = NULL;
   1130 	break;
   1131     default:
   1132 	break;
   1133     }
   1134 }
   1135 
   1136 /*
   1137  * .PATH<suffix> has to be handled specially.
   1138  * Call on the suffix module to give us a path to modify.
   1139  */
   1140 static Boolean
   1141 ParseDoDependencyTargetPath(const char *line, SearchPathList **inout_paths)
   1142 {
   1143     SearchPath *path;
   1144 
   1145     path = Suff_GetPath(&line[5]);
   1146     if (path == NULL) {
   1147 	Parse_Error(PARSE_FATAL,
   1148 		    "Suffix '%s' not defined (yet)",
   1149 		    &line[5]);
   1150 	return FALSE;
   1151     }
   1152 
   1153     if (*inout_paths == NULL)
   1154 	*inout_paths = Lst_New();
   1155     Lst_Append(*inout_paths, path);
   1156 
   1157     return TRUE;
   1158 }
   1159 
   1160 /*
   1161  * See if it's a special target and if so set specType to match it.
   1162  */
   1163 static Boolean
   1164 ParseDoDependencyTarget(const char *line, ParseSpecial *inout_specType,
   1165 			GNodeType *out_tOp, SearchPathList **inout_paths)
   1166 {
   1167     int keywd;
   1168 
   1169     if (!(*line == '.' && ch_isupper(line[1])))
   1170 	return TRUE;
   1171 
   1172     /*
   1173      * See if the target is a special target that must have it
   1174      * or its sources handled specially.
   1175      */
   1176     keywd = ParseFindKeyword(line);
   1177     if (keywd != -1) {
   1178 	if (*inout_specType == SP_PATH && parseKeywords[keywd].spec != SP_PATH) {
   1179 	    Parse_Error(PARSE_FATAL, "Mismatched special targets");
   1180 	    return FALSE;
   1181 	}
   1182 
   1183 	*inout_specType = parseKeywords[keywd].spec;
   1184 	*out_tOp = parseKeywords[keywd].op;
   1185 
   1186 	ParseDoDependencyTargetSpecial(inout_specType, line, inout_paths);
   1187 
   1188     } else if (strncmp(line, ".PATH", 5) == 0) {
   1189 	*inout_specType = SP_PATH;
   1190 	if (!ParseDoDependencyTargetPath(line, inout_paths))
   1191 	    return FALSE;
   1192     }
   1193     return TRUE;
   1194 }
   1195 
   1196 static void
   1197 ParseDoDependencyTargetMundane(char *line, StringList *curTargs)
   1198 {
   1199     if (Dir_HasWildcards(line)) {
   1200 	/*
   1201 	 * Targets are to be sought only in the current directory,
   1202 	 * so create an empty path for the thing. Note we need to
   1203 	 * use Dir_Destroy in the destruction of the path as the
   1204 	 * Dir module could have added a directory to the path...
   1205 	 */
   1206 	SearchPath *emptyPath = Lst_New();
   1207 
   1208 	Dir_Expand(line, emptyPath, curTargs);
   1209 
   1210 	Lst_Destroy(emptyPath, Dir_Destroy);
   1211     } else {
   1212 	/*
   1213 	 * No wildcards, but we want to avoid code duplication,
   1214 	 * so create a list with the word on it.
   1215 	 */
   1216 	Lst_Append(curTargs, line);
   1217     }
   1218 
   1219     /* Apply the targets. */
   1220 
   1221     while (!Lst_IsEmpty(curTargs)) {
   1222 	char *targName = Lst_Dequeue(curTargs);
   1223 	GNode *gn = Suff_IsTransform(targName)
   1224 		    ? Suff_AddTransform(targName)
   1225 		    : Targ_GetNode(targName);
   1226 	if (doing_depend)
   1227 	    ParseMark(gn);
   1228 
   1229 	Lst_Append(targets, gn);
   1230     }
   1231 }
   1232 
   1233 static void
   1234 ParseDoDependencyTargetExtraWarn(char **pp, const char *lstart)
   1235 {
   1236     Boolean warning = FALSE;
   1237     char *cp = *pp;
   1238 
   1239     while (*cp != '\0') {
   1240 	if (!ParseIsEscaped(lstart, cp) && (*cp == '!' || *cp == ':'))
   1241 	    break;
   1242 	if (ParseIsEscaped(lstart, cp) || (*cp != ' ' && *cp != '\t'))
   1243 	    warning = TRUE;
   1244 	cp++;
   1245     }
   1246     if (warning)
   1247 	Parse_Error(PARSE_WARNING, "Extra target ignored");
   1248 
   1249     *pp = cp;
   1250 }
   1251 
   1252 static void
   1253 ParseDoDependencyCheckSpec(ParseSpecial specType)
   1254 {
   1255     switch (specType) {
   1256     default:
   1257 	Parse_Error(PARSE_WARNING,
   1258 		    "Special and mundane targets don't mix. Mundane ones ignored");
   1259 	break;
   1260     case SP_DEFAULT:
   1261     case SP_STALE:
   1262     case SP_BEGIN:
   1263     case SP_END:
   1264     case SP_ERROR:
   1265     case SP_INTERRUPT:
   1266 	/*
   1267 	 * These four create nodes on which to hang commands, so
   1268 	 * targets shouldn't be empty...
   1269 	 */
   1270     case SP_NOT:
   1271 	/*
   1272 	 * Nothing special here -- targets can be empty if it wants.
   1273 	 */
   1274 	break;
   1275     }
   1276 }
   1277 
   1278 static Boolean
   1279 ParseDoDependencyParseOp(char **pp, const char *lstart, GNodeType *out_op)
   1280 {
   1281     const char *cp = *pp;
   1282 
   1283     if (*cp == '!') {
   1284 	*out_op = OP_FORCE;
   1285 	(*pp)++;
   1286 	return TRUE;
   1287     }
   1288 
   1289     if (*cp == ':') {
   1290 	if (cp[1] == ':') {
   1291 	    *out_op = OP_DOUBLEDEP;
   1292 	    (*pp) += 2;
   1293 	} else {
   1294 	    *out_op = OP_DEPENDS;
   1295 	    (*pp)++;
   1296 	}
   1297 	return TRUE;
   1298     }
   1299 
   1300     {
   1301 	const char *msg = lstart[0] == '.' ? "Unknown directive"
   1302 					   : "Missing dependency operator";
   1303 	Parse_Error(PARSE_FATAL, "%s", msg);
   1304 	return FALSE;
   1305     }
   1306 }
   1307 
   1308 static void
   1309 ClearPaths(SearchPathList *paths)
   1310 {
   1311     if (paths != NULL) {
   1312 	SearchPathListNode *ln;
   1313 	for (ln = paths->first; ln != NULL; ln = ln->next)
   1314 	    Dir_ClearPath(ln->datum);
   1315     }
   1316 
   1317     Dir_SetPATH();
   1318 }
   1319 
   1320 static void
   1321 ParseDoDependencySourcesEmpty(ParseSpecial specType, SearchPathList *paths)
   1322 {
   1323     switch (specType) {
   1324     case SP_SUFFIXES:
   1325 	Suff_ClearSuffixes();
   1326 	break;
   1327     case SP_PRECIOUS:
   1328 	allPrecious = TRUE;
   1329 	break;
   1330     case SP_IGNORE:
   1331 	opts.ignoreErrors = TRUE;
   1332 	break;
   1333     case SP_SILENT:
   1334 	opts.beSilent = TRUE;
   1335 	break;
   1336     case SP_PATH:
   1337 	ClearPaths(paths);
   1338 	break;
   1339 #ifdef POSIX
   1340     case SP_POSIX:
   1341 	Var_Set("%POSIX", "1003.2", VAR_GLOBAL);
   1342 	break;
   1343 #endif
   1344     default:
   1345 	break;
   1346     }
   1347 }
   1348 
   1349 static void
   1350 AddToPaths(const char *dir, SearchPathList *paths)
   1351 {
   1352     if (paths != NULL) {
   1353 	SearchPathListNode *ln;
   1354 	for (ln = paths->first; ln != NULL; ln = ln->next)
   1355 	    (void)Dir_AddDir(ln->datum, dir);
   1356     }
   1357 }
   1358 
   1359 /*
   1360  * If the target was one that doesn't take files as its sources
   1361  * but takes something like suffixes, we take each
   1362  * space-separated word on the line as a something and deal
   1363  * with it accordingly.
   1364  *
   1365  * If the target was .SUFFIXES, we take each source as a
   1366  * suffix and add it to the list of suffixes maintained by the
   1367  * Suff module.
   1368  *
   1369  * If the target was a .PATH, we add the source as a directory
   1370  * to search on the search path.
   1371  *
   1372  * If it was .INCLUDES, the source is taken to be the suffix of
   1373  * files which will be #included and whose search path should
   1374  * be present in the .INCLUDES variable.
   1375  *
   1376  * If it was .LIBS, the source is taken to be the suffix of
   1377  * files which are considered libraries and whose search path
   1378  * should be present in the .LIBS variable.
   1379  *
   1380  * If it was .NULL, the source is the suffix to use when a file
   1381  * has no valid suffix.
   1382  *
   1383  * If it was .OBJDIR, the source is a new definition for .OBJDIR,
   1384  * and will cause make to do a new chdir to that path.
   1385  */
   1386 static void
   1387 ParseDoDependencySourceSpecial(ParseSpecial specType, char *word,
   1388 			       SearchPathList *paths)
   1389 {
   1390     switch (specType) {
   1391     case SP_SUFFIXES:
   1392 	Suff_AddSuffix(word, &mainNode);
   1393 	break;
   1394     case SP_PATH:
   1395 	AddToPaths(word, paths);
   1396 	break;
   1397     case SP_INCLUDES:
   1398 	Suff_AddInclude(word);
   1399 	break;
   1400     case SP_LIBS:
   1401 	Suff_AddLib(word);
   1402 	break;
   1403     case SP_NULL:
   1404 	Suff_SetNull(word);
   1405 	break;
   1406     case SP_OBJDIR:
   1407 	Main_SetObjdir(FALSE, "%s", word);
   1408 	break;
   1409     default:
   1410 	break;
   1411     }
   1412 }
   1413 
   1414 static Boolean
   1415 ParseDoDependencyTargets(char **inout_cp,
   1416 			 char **inout_line,
   1417 			 const char *lstart,
   1418 			 ParseSpecial *inout_specType,
   1419 			 GNodeType *inout_tOp,
   1420 			 SearchPathList **inout_paths,
   1421 			 StringList *curTargs)
   1422 {
   1423     char *cp = *inout_cp;
   1424     char *line = *inout_line;
   1425     char savec;
   1426 
   1427     for (;;) {
   1428 	/*
   1429 	 * Here LINE points to the beginning of the next word, and
   1430 	 * LSTART points to the actual beginning of the line.
   1431 	 */
   1432 
   1433 	/* Find the end of the next word. */
   1434 	cp = line;
   1435 	ParseDependencyTargetWord(&cp, lstart);
   1436 
   1437 	/*
   1438 	 * If the word is followed by a left parenthesis, it's the
   1439 	 * name of an object file inside an archive (ar file).
   1440 	 */
   1441 	if (!ParseIsEscaped(lstart, cp) && *cp == '(') {
   1442 	    /*
   1443 	     * Archives must be handled specially to make sure the OP_ARCHV
   1444 	     * flag is set in their 'type' field, for one thing, and because
   1445 	     * things like "archive(file1.o file2.o file3.o)" are permissible.
   1446 	     * Arch_ParseArchive will set 'line' to be the first non-blank
   1447 	     * after the archive-spec. It creates/finds nodes for the members
   1448 	     * and places them on the given list, returning TRUE if all
   1449 	     * went well and FALSE if there was an error in the
   1450 	     * specification. On error, line should remain untouched.
   1451 	     */
   1452 	    if (!Arch_ParseArchive(&line, targets, VAR_CMDLINE)) {
   1453 		Parse_Error(PARSE_FATAL,
   1454 			    "Error in archive specification: \"%s\"", line);
   1455 		return FALSE;
   1456 	    } else {
   1457 		/* Done with this word; on to the next. */
   1458 		cp = line;
   1459 		continue;
   1460 	    }
   1461 	}
   1462 
   1463 	if (!*cp) {
   1464 	    ParseErrorNoDependency(lstart);
   1465 	    return FALSE;
   1466 	}
   1467 
   1468 	/* Insert a null terminator. */
   1469 	savec = *cp;
   1470 	*cp = '\0';
   1471 
   1472 	if (!ParseDoDependencyTarget(line, inout_specType, inout_tOp,
   1473 				     inout_paths))
   1474 	    return FALSE;
   1475 
   1476 	/*
   1477 	 * Have word in line. Get or create its node and stick it at
   1478 	 * the end of the targets list
   1479 	 */
   1480 	if (*inout_specType == SP_NOT && *line != '\0')
   1481 	    ParseDoDependencyTargetMundane(line, curTargs);
   1482 	else if (*inout_specType == SP_PATH && *line != '.' && *line != '\0')
   1483 	    Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", line);
   1484 
   1485 	/* Don't need the inserted null terminator any more. */
   1486 	*cp = savec;
   1487 
   1488 	/*
   1489 	 * If it is a special type and not .PATH, it's the only target we
   1490 	 * allow on this line...
   1491 	 */
   1492 	if (*inout_specType != SP_NOT && *inout_specType != SP_PATH)
   1493 	    ParseDoDependencyTargetExtraWarn(&cp, lstart);
   1494 	else
   1495 	    pp_skip_whitespace(&cp);
   1496 
   1497 	line = cp;
   1498 	if (*line == '\0')
   1499 	    break;
   1500 	if ((*line == '!' || *line == ':') && !ParseIsEscaped(lstart, line))
   1501 	    break;
   1502     }
   1503 
   1504     *inout_cp = cp;
   1505     *inout_line = line;
   1506     return TRUE;
   1507 }
   1508 
   1509 static void
   1510 ParseDoDependencySourcesSpecial(char *start, char *end,
   1511 				ParseSpecial specType, SearchPathList *paths)
   1512 {
   1513     char savec;
   1514 
   1515     while (*start) {
   1516 	while (*end && !ch_isspace(*end))
   1517 	    end++;
   1518 	savec = *end;
   1519 	*end = '\0';
   1520 	ParseDoDependencySourceSpecial(specType, start, paths);
   1521 	*end = savec;
   1522 	if (savec != '\0')
   1523 	    end++;
   1524 	pp_skip_whitespace(&end);
   1525 	start = end;
   1526     }
   1527 }
   1528 
   1529 static Boolean
   1530 ParseDoDependencySourcesMundane(char *start, char *end,
   1531 				ParseSpecial specType, GNodeType tOp)
   1532 {
   1533     while (*start != '\0') {
   1534 	/*
   1535 	 * The targets take real sources, so we must beware of archive
   1536 	 * specifications (i.e. things with left parentheses in them)
   1537 	 * and handle them accordingly.
   1538 	 */
   1539 	for (; *end && !ch_isspace(*end); end++) {
   1540 	    if (*end == '(' && end > start && end[-1] != '$') {
   1541 		/*
   1542 		 * Only stop for a left parenthesis if it isn't at the
   1543 		 * start of a word (that'll be for variable changes
   1544 		 * later) and isn't preceded by a dollar sign (a dynamic
   1545 		 * source).
   1546 		 */
   1547 		break;
   1548 	    }
   1549 	}
   1550 
   1551 	if (*end == '(') {
   1552 	    GNodeList *sources = Lst_New();
   1553 	    if (!Arch_ParseArchive(&start, sources, VAR_CMDLINE)) {
   1554 		Parse_Error(PARSE_FATAL,
   1555 			    "Error in source archive spec \"%s\"", start);
   1556 		return FALSE;
   1557 	    }
   1558 
   1559 	    while (!Lst_IsEmpty(sources)) {
   1560 		GNode *gn = Lst_Dequeue(sources);
   1561 		ParseDoSrc(tOp, gn->name, specType);
   1562 	    }
   1563 	    Lst_Free(sources);
   1564 	    end = start;
   1565 	} else {
   1566 	    if (*end) {
   1567 		*end = '\0';
   1568 		end++;
   1569 	    }
   1570 
   1571 	    ParseDoSrc(tOp, start, specType);
   1572 	}
   1573 	pp_skip_whitespace(&end);
   1574 	start = end;
   1575     }
   1576     return TRUE;
   1577 }
   1578 
   1579 /* Parse a dependency line consisting of targets, followed by a dependency
   1580  * operator, optionally followed by sources.
   1581  *
   1582  * The nodes of the sources are linked as children to the nodes of the
   1583  * targets. Nodes are created as necessary.
   1584  *
   1585  * The operator is applied to each node in the global 'targets' list,
   1586  * which is where the nodes found for the targets are kept, by means of
   1587  * the ParseDoOp function.
   1588  *
   1589  * The sources are parsed in much the same way as the targets, except
   1590  * that they are expanded using the wildcarding scheme of the C-Shell,
   1591  * and all instances of the resulting words in the list of all targets
   1592  * are found. Each of the resulting nodes is then linked to each of the
   1593  * targets as one of its children.
   1594  *
   1595  * Certain targets and sources such as .PHONY or .PRECIOUS are handled
   1596  * specially. These are the ones detailed by the specType variable.
   1597  *
   1598  * The storing of transformation rules such as '.c.o' is also taken care of
   1599  * here. A target is recognized as a transformation rule by calling
   1600  * Suff_IsTransform. If it is a transformation rule, its node is gotten
   1601  * from the suffix module via Suff_AddTransform rather than the standard
   1602  * Targ_FindNode in the target module.
   1603  */
   1604 static void
   1605 ParseDoDependency(char *line)
   1606 {
   1607     char *cp;			/* our current position */
   1608     GNodeType op;		/* the operator on the line */
   1609     SearchPathList *paths;	/* search paths to alter when parsing
   1610 				 * a list of .PATH targets */
   1611     int tOp;			/* operator from special target */
   1612     StringList *curTargs;	/* target names to be found and added
   1613 				 * to the targets list */
   1614     char *lstart = line;
   1615 
   1616     /*
   1617      * specType contains the SPECial TYPE of the current target. It is SP_NOT
   1618      * if the target is unspecial. If it *is* special, however, the children
   1619      * are linked as children of the parent but not vice versa.
   1620      */
   1621     ParseSpecial specType = SP_NOT;
   1622 
   1623     DEBUG1(PARSE, "ParseDoDependency(%s)\n", line);
   1624     tOp = 0;
   1625 
   1626     paths = NULL;
   1627 
   1628     curTargs = Lst_New();
   1629 
   1630     /*
   1631      * First, grind through the targets.
   1632      */
   1633     if (!ParseDoDependencyTargets(&cp, &line, lstart, &specType, &tOp, &paths,
   1634 				  curTargs))
   1635 	goto out;
   1636 
   1637     /*
   1638      * Don't need the list of target names anymore...
   1639      */
   1640     Lst_Free(curTargs);
   1641     curTargs = NULL;
   1642 
   1643     if (!Lst_IsEmpty(targets))
   1644 	ParseDoDependencyCheckSpec(specType);
   1645 
   1646     /*
   1647      * Have now parsed all the target names. Must parse the operator next.
   1648      */
   1649     if (!ParseDoDependencyParseOp(&cp, lstart, &op))
   1650 	goto out;
   1651 
   1652     /*
   1653      * Apply the operator to the target. This is how we remember which
   1654      * operator a target was defined with. It fails if the operator
   1655      * used isn't consistent across all references.
   1656      */
   1657     ApplyDependencyOperator(op);
   1658 
   1659     /*
   1660      * Onward to the sources.
   1661      *
   1662      * LINE will now point to the first source word, if any, or the
   1663      * end of the string if not.
   1664      */
   1665     pp_skip_whitespace(&cp);
   1666     line = cp;
   1667 
   1668     /*
   1669      * Several special targets take different actions if present with no
   1670      * sources:
   1671      *	a .SUFFIXES line with no sources clears out all old suffixes
   1672      *	a .PRECIOUS line makes all targets precious
   1673      *	a .IGNORE line ignores errors for all targets
   1674      *	a .SILENT line creates silence when making all targets
   1675      *	a .PATH removes all directories from the search path(s).
   1676      */
   1677     if (!*line) {
   1678 	ParseDoDependencySourcesEmpty(specType, paths);
   1679     } else if (specType == SP_MFLAGS) {
   1680 	/*
   1681 	 * Call on functions in main.c to deal with these arguments and
   1682 	 * set the initial character to a null-character so the loop to
   1683 	 * get sources won't get anything
   1684 	 */
   1685 	Main_ParseArgLine(line);
   1686 	*line = '\0';
   1687     } else if (specType == SP_SHELL) {
   1688 	if (!Job_ParseShell(line)) {
   1689 	    Parse_Error(PARSE_FATAL, "improper shell specification");
   1690 	    goto out;
   1691 	}
   1692 	*line = '\0';
   1693     } else if (specType == SP_NOTPARALLEL || specType == SP_SINGLESHELL ||
   1694 	       specType == SP_DELETE_ON_ERROR) {
   1695 	*line = '\0';
   1696     }
   1697 
   1698     /*
   1699      * NOW GO FOR THE SOURCES
   1700      */
   1701     if (specType == SP_SUFFIXES || specType == SP_PATH ||
   1702 	specType == SP_INCLUDES || specType == SP_LIBS ||
   1703 	specType == SP_NULL || specType == SP_OBJDIR)
   1704     {
   1705 	ParseDoDependencySourcesSpecial(line, cp, specType, paths);
   1706 	if (paths) {
   1707 	    Lst_Free(paths);
   1708 	    paths = NULL;
   1709 	}
   1710 	if (specType == SP_PATH)
   1711 	    Dir_SetPATH();
   1712     } else {
   1713 	assert(paths == NULL);
   1714 	if (!ParseDoDependencySourcesMundane(line, cp, specType, tOp))
   1715 	    goto out;
   1716     }
   1717 
   1718     FindMainTarget();
   1719 
   1720 out:
   1721     if (paths != NULL)
   1722 	Lst_Free(paths);
   1723     if (curTargs != NULL)
   1724 	Lst_Free(curTargs);
   1725 }
   1726 
   1727 typedef struct VarAssignParsed {
   1728     const char *nameStart;	/* unexpanded */
   1729     const char *nameEnd;	/* before operator adjustment */
   1730     const char *eq;		/* the '=' of the assignment operator */
   1731 } VarAssignParsed;
   1732 
   1733 /* Determine the assignment operator and adjust the end of the variable
   1734  * name accordingly. */
   1735 static void
   1736 AdjustVarassignOp(const VarAssignParsed *pvar, const char *value,
   1737 		  VarAssign *out_var)
   1738 {
   1739     const char *op = pvar->eq;
   1740     const char * const name = pvar->nameStart;
   1741     VarAssignOp type;
   1742 
   1743     if (op > name && op[-1] == '+') {
   1744 	type = VAR_APPEND;
   1745 	op--;
   1746 
   1747     } else if (op > name && op[-1] == '?') {
   1748 	op--;
   1749 	type = VAR_DEFAULT;
   1750 
   1751     } else if (op > name && op[-1] == ':') {
   1752 	op--;
   1753 	type = VAR_SUBST;
   1754 
   1755     } else if (op > name && op[-1] == '!') {
   1756 	op--;
   1757 	type = VAR_SHELL;
   1758 
   1759     } else {
   1760 	type = VAR_NORMAL;
   1761 #ifdef SUNSHCMD
   1762 	while (op > name && ch_isspace(op[-1]))
   1763 	    op--;
   1764 
   1765 	if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
   1766 	    type = VAR_SHELL;
   1767 	    op -= 3;
   1768 	}
   1769 #endif
   1770     }
   1771 
   1772     {
   1773 	const char *nameEnd = pvar->nameEnd < op ? pvar->nameEnd : op;
   1774 	out_var->varname = bmake_strsedup(pvar->nameStart, nameEnd);
   1775 	out_var->op = type;
   1776 	out_var->value = value;
   1777     }
   1778 }
   1779 
   1780 /* Parse a variable assignment, consisting of a single-word variable name,
   1781  * optional whitespace, an assignment operator, optional whitespace and the
   1782  * variable value.
   1783  *
   1784  * Note: There is a lexical ambiguity with assignment modifier characters
   1785  * in variable names. This routine interprets the character before the =
   1786  * as a modifier. Therefore, an assignment like
   1787  *	C++=/usr/bin/CC
   1788  * is interpreted as "C+ +=" instead of "C++ =".
   1789  *
   1790  * Used for both lines in a file and command line arguments. */
   1791 Boolean
   1792 Parse_IsVar(const char *p, VarAssign *out_var)
   1793 {
   1794     VarAssignParsed pvar;
   1795     const char *firstSpace = NULL;
   1796     int level = 0;
   1797 
   1798     cpp_skip_hspace(&p);	/* Skip to variable name */
   1799 
   1800     /* During parsing, the '+' of the '+=' operator is initially parsed
   1801      * as part of the variable name.  It is later corrected, as is the ':sh'
   1802      * modifier. Of these two (nameEnd and op), the earlier one determines the
   1803      * actual end of the variable name. */
   1804     pvar.nameStart = p;
   1805 #ifdef CLEANUP
   1806     pvar.nameEnd = NULL;
   1807     pvar.eq = NULL;
   1808 #endif
   1809 
   1810     /* Scan for one of the assignment operators outside a variable expansion */
   1811     while (*p != '\0') {
   1812 	char ch = *p++;
   1813 	if (ch == '(' || ch == '{') {
   1814 	    level++;
   1815 	    continue;
   1816 	}
   1817 	if (ch == ')' || ch == '}') {
   1818 	    level--;
   1819 	    continue;
   1820 	}
   1821 
   1822 	if (level != 0)
   1823 	    continue;
   1824 
   1825 	if (ch == ' ' || ch == '\t')
   1826 	    if (firstSpace == NULL)
   1827 		firstSpace = p - 1;
   1828 	while (ch == ' ' || ch == '\t')
   1829 	    ch = *p++;
   1830 
   1831 #ifdef SUNSHCMD
   1832 	if (ch == ':' && p[0] == 's' && p[1] == 'h') {
   1833 	    p += 2;
   1834 	    continue;
   1835 	}
   1836 #endif
   1837 	if (ch == '=') {
   1838 	    pvar.eq = p - 1;
   1839 	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p - 1;
   1840 	    cpp_skip_whitespace(&p);
   1841 	    AdjustVarassignOp(&pvar, p, out_var);
   1842 	    return TRUE;
   1843 	}
   1844 	if (*p == '=' && (ch == '+' || ch == ':' || ch == '?' || ch == '!')) {
   1845 	    pvar.eq = p;
   1846 	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p;
   1847 	    p++;
   1848 	    cpp_skip_whitespace(&p);
   1849 	    AdjustVarassignOp(&pvar, p, out_var);
   1850 	    return TRUE;
   1851 	}
   1852 	if (firstSpace != NULL)
   1853 	    return FALSE;
   1854     }
   1855 
   1856     return FALSE;
   1857 }
   1858 
   1859 static void
   1860 VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *ctxt)
   1861 {
   1862     if (opts.lint) {
   1863 	if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
   1864 	    /* Check for syntax errors such as unclosed expressions or
   1865 	     * unknown modifiers. */
   1866 	    char *expandedValue;
   1867 
   1868 	    (void)Var_Subst(uvalue, ctxt, VARE_NONE, &expandedValue);
   1869 	    /* TODO: handle errors */
   1870 	    free(expandedValue);
   1871 	}
   1872     }
   1873 }
   1874 
   1875 static void
   1876 VarAssign_EvalSubst(const char *name, const char *uvalue, GNode *ctxt,
   1877 		    const char **out_avalue, void **out_avalue_freeIt)
   1878 {
   1879     const char *avalue = uvalue;
   1880     char *evalue;
   1881     Boolean savedPreserveUndefined = preserveUndefined;
   1882 
   1883     /* TODO: Can this assignment to preserveUndefined be moved further down
   1884      * to the actually interesting Var_Subst call, without affecting any
   1885      * edge cases?
   1886      *
   1887      * It might affect the implicit expansion of the variable name in the
   1888      * Var_Exists and Var_Set calls, even though it's unlikely that anyone
   1889      * cared about this edge case when adding this code.  In addition,
   1890      * variable assignments should not refer to any undefined variables in
   1891      * the variable name. */
   1892     preserveUndefined = TRUE;
   1893 
   1894     /*
   1895      * make sure that we set the variable the first time to nothing
   1896      * so that it gets substituted!
   1897      */
   1898     if (!Var_Exists(name, ctxt))
   1899 	Var_Set(name, "", ctxt);
   1900 
   1901     (void)Var_Subst(uvalue, ctxt, VARE_WANTRES|VARE_KEEP_DOLLAR, &evalue);
   1902     /* TODO: handle errors */
   1903     preserveUndefined = savedPreserveUndefined;
   1904     avalue = evalue;
   1905     Var_Set(name, avalue, ctxt);
   1906 
   1907     *out_avalue = avalue;
   1908     *out_avalue_freeIt = evalue;
   1909 }
   1910 
   1911 static void
   1912 VarAssign_EvalShell(const char *name, const char *uvalue, GNode *ctxt,
   1913 		    const char **out_avalue, void **out_avalue_freeIt)
   1914 {
   1915     const char *cmd, *errfmt;
   1916     char *cmdOut;
   1917     void *cmd_freeIt = NULL;
   1918 
   1919     cmd = uvalue;
   1920     if (strchr(cmd, '$') != NULL) {
   1921 	char *ecmd;
   1922 	(void)Var_Subst(cmd, VAR_CMDLINE, VARE_WANTRES | VARE_UNDEFERR, &ecmd);
   1923 	/* TODO: handle errors */
   1924 	cmd = cmd_freeIt = ecmd;
   1925     }
   1926 
   1927     cmdOut = Cmd_Exec(cmd, &errfmt);
   1928     Var_Set(name, cmdOut, ctxt);
   1929     *out_avalue = *out_avalue_freeIt = cmdOut;
   1930 
   1931     if (errfmt)
   1932 	Parse_Error(PARSE_WARNING, errfmt, cmd);
   1933 
   1934     free(cmd_freeIt);
   1935 }
   1936 
   1937 /* Perform a variable assignment.
   1938  *
   1939  * The actual value of the variable is returned in *out_avalue and
   1940  * *out_avalue_freeIt.  Especially for VAR_SUBST and VAR_SHELL this can differ
   1941  * from the literal value.
   1942  *
   1943  * Return whether the assignment was actually done.  The assignment is only
   1944  * skipped if the operator is '?=' and the variable already exists. */
   1945 static Boolean
   1946 VarAssign_Eval(const char *name, VarAssignOp op, const char *uvalue,
   1947 	       GNode *ctxt, const char **out_avalue, void **out_avalue_freeIt)
   1948 {
   1949     const char *avalue = uvalue;
   1950     void *avalue_freeIt = NULL;
   1951 
   1952     if (op == VAR_APPEND)
   1953 	Var_Append(name, uvalue, ctxt);
   1954     else if (op == VAR_SUBST)
   1955 	VarAssign_EvalSubst(name, uvalue, ctxt, &avalue, &avalue_freeIt);
   1956     else if (op == VAR_SHELL)
   1957 	VarAssign_EvalShell(name, uvalue, ctxt, &avalue, &avalue_freeIt);
   1958     else {
   1959 	if (op == VAR_DEFAULT && Var_Exists(name, ctxt)) {
   1960 	    *out_avalue_freeIt = NULL;
   1961 	    return FALSE;
   1962 	}
   1963 
   1964 	/* Normal assignment -- just do it. */
   1965 	Var_Set(name, uvalue, ctxt);
   1966     }
   1967 
   1968     *out_avalue = avalue;
   1969     *out_avalue_freeIt = avalue_freeIt;
   1970     return TRUE;
   1971 }
   1972 
   1973 static void
   1974 VarAssignSpecial(const char *name, const char *avalue)
   1975 {
   1976     if (strcmp(name, MAKEOVERRIDES) == 0)
   1977 	Main_ExportMAKEFLAGS(FALSE);	/* re-export MAKEFLAGS */
   1978     else if (strcmp(name, ".CURDIR") == 0) {
   1979 	/*
   1980 	 * Someone is being (too?) clever...
   1981 	 * Let's pretend they know what they are doing and
   1982 	 * re-initialize the 'cur' CachedDir.
   1983 	 */
   1984 	Dir_InitCur(avalue);
   1985 	Dir_SetPATH();
   1986     } else if (strcmp(name, MAKE_JOB_PREFIX) == 0)
   1987 	Job_SetPrefix();
   1988     else if (strcmp(name, MAKE_EXPORTED) == 0)
   1989 	Var_Export(avalue, FALSE);
   1990 }
   1991 
   1992 /* Perform the variable variable assignment in the given context. */
   1993 void
   1994 Parse_DoVar(VarAssign *var, GNode *ctxt)
   1995 {
   1996     const char *avalue;		/* actual value (maybe expanded) */
   1997     void *avalue_freeIt;
   1998 
   1999     VarCheckSyntax(var->op, var->value, ctxt);
   2000     if (VarAssign_Eval(var->varname, var->op, var->value, ctxt,
   2001 		       &avalue, &avalue_freeIt))
   2002 	VarAssignSpecial(var->varname, avalue);
   2003 
   2004     free(avalue_freeIt);
   2005     free(var->varname);
   2006 }
   2007 
   2008 
   2009 /* See if the command possibly calls a sub-make by using the variable
   2010  * expressions ${.MAKE}, ${MAKE} or the plain word "make". */
   2011 static Boolean
   2012 MaybeSubMake(const char *cmd)
   2013 {
   2014     const char *start;
   2015 
   2016     for (start = cmd; *start != '\0'; start++) {
   2017 	const char *p = start;
   2018 	char endc;
   2019 
   2020 	/* XXX: What if progname != "make"? */
   2021 	if (p[0] == 'm' && p[1] == 'a' && p[2] == 'k' && p[3] == 'e')
   2022 	    if (start == cmd || !ch_isalnum(p[-1]))
   2023 		if (!ch_isalnum(p[4]))
   2024 		    return TRUE;
   2025 
   2026 	if (*p != '$')
   2027 	    continue;
   2028 	p++;
   2029 
   2030 	if (*p == '{')
   2031 	    endc = '}';
   2032 	else if (*p == '(')
   2033 	    endc = ')';
   2034 	else
   2035 	    continue;
   2036 	p++;
   2037 
   2038 	if (*p == '.')		/* Accept either ${.MAKE} or ${MAKE}. */
   2039 	    p++;
   2040 
   2041 	if (p[0] == 'M' && p[1] == 'A' && p[2] == 'K' && p[3] == 'E')
   2042 	    if (p[4] == endc)
   2043 		return TRUE;
   2044     }
   2045     return FALSE;
   2046 }
   2047 
   2048 /* Append the command to the target node.
   2049  *
   2050  * The node may be marked as a submake node if the command is determined to
   2051  * be that. */
   2052 static void
   2053 ParseAddCmd(GNode *gn, char *cmd)
   2054 {
   2055     /* Add to last (ie current) cohort for :: targets */
   2056     if ((gn->type & OP_DOUBLEDEP) && gn->cohorts->last != NULL)
   2057 	gn = gn->cohorts->last->datum;
   2058 
   2059     /* if target already supplied, ignore commands */
   2060     if (!(gn->type & OP_HAS_COMMANDS)) {
   2061 	Lst_Append(gn->commands, cmd);
   2062 	if (MaybeSubMake(cmd))
   2063 	    gn->type |= OP_SUBMAKE;
   2064 	ParseMark(gn);
   2065     } else {
   2066 #if 0
   2067 	/* XXX: We cannot do this until we fix the tree */
   2068 	Lst_Append(gn->commands, cmd);
   2069 	Parse_Error(PARSE_WARNING,
   2070 		     "overriding commands for target \"%s\"; "
   2071 		     "previous commands defined at %s: %d ignored",
   2072 		     gn->name, gn->fname, gn->lineno);
   2073 #else
   2074 	Parse_Error(PARSE_WARNING,
   2075 		    "duplicate script for target \"%s\" ignored",
   2076 		    gn->name);
   2077 	ParseErrorInternal(gn->fname, (size_t)gn->lineno, PARSE_WARNING,
   2078 			   "using previous script for \"%s\" defined here",
   2079 			   gn->name);
   2080 #endif
   2081     }
   2082 }
   2083 
   2084 /* Add a directory to the path searched for included makefiles bracketed
   2085  * by double-quotes. */
   2086 void
   2087 Parse_AddIncludeDir(const char *dir)
   2088 {
   2089     (void)Dir_AddDir(parseIncPath, dir);
   2090 }
   2091 
   2092 /* Push to another file.
   2093  *
   2094  * The input is the line minus the '.'. A file spec is a string enclosed in
   2095  * <> or "". The <> file is looked for only in sysIncPath. The "" file is
   2096  * first searched in the parsedir and then in the directories specified by
   2097  * the -I command line options.
   2098  */
   2099 static void
   2100 Parse_include_file(char *file, Boolean isSystem, Boolean depinc, Boolean silent)
   2101 {
   2102     struct loadedfile *lf;
   2103     char *fullname;		/* full pathname of file */
   2104     char *newName;
   2105     char *prefEnd, *incdir;
   2106     int fd;
   2107     int i;
   2108 
   2109     /*
   2110      * Now we know the file's name and its search path, we attempt to
   2111      * find the durn thing. A return of NULL indicates the file don't
   2112      * exist.
   2113      */
   2114     fullname = file[0] == '/' ? bmake_strdup(file) : NULL;
   2115 
   2116     if (fullname == NULL && !isSystem) {
   2117 	/*
   2118 	 * Include files contained in double-quotes are first searched for
   2119 	 * relative to the including file's location. We don't want to
   2120 	 * cd there, of course, so we just tack on the old file's
   2121 	 * leading path components and call Dir_FindFile to see if
   2122 	 * we can locate the beast.
   2123 	 */
   2124 
   2125 	incdir = bmake_strdup(CurFile()->fname);
   2126 	prefEnd = strrchr(incdir, '/');
   2127 	if (prefEnd != NULL) {
   2128 	    *prefEnd = '\0';
   2129 	    /* Now do lexical processing of leading "../" on the filename */
   2130 	    for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
   2131 		prefEnd = strrchr(incdir + 1, '/');
   2132 		if (prefEnd == NULL || strcmp(prefEnd, "/..") == 0)
   2133 		    break;
   2134 		*prefEnd = '\0';
   2135 	    }
   2136 	    newName = str_concat3(incdir, "/", file + i);
   2137 	    fullname = Dir_FindFile(newName, parseIncPath);
   2138 	    if (fullname == NULL)
   2139 		fullname = Dir_FindFile(newName, dirSearchPath);
   2140 	    free(newName);
   2141 	}
   2142 	free(incdir);
   2143 
   2144 	if (fullname == NULL) {
   2145 	    /*
   2146 	     * Makefile wasn't found in same directory as included makefile.
   2147 	     * Search for it first on the -I search path,
   2148 	     * then on the .PATH search path, if not found in a -I directory.
   2149 	     * If we have a suffix specific path we should use that.
   2150 	     */
   2151 	    char *suff;
   2152 	    SearchPath *suffPath = NULL;
   2153 
   2154 	    if ((suff = strrchr(file, '.'))) {
   2155 		suffPath = Suff_GetPath(suff);
   2156 		if (suffPath != NULL)
   2157 		    fullname = Dir_FindFile(file, suffPath);
   2158 	    }
   2159 	    if (fullname == NULL) {
   2160 		fullname = Dir_FindFile(file, parseIncPath);
   2161 		if (fullname == NULL)
   2162 		    fullname = Dir_FindFile(file, dirSearchPath);
   2163 	    }
   2164 	}
   2165     }
   2166 
   2167     /* Looking for a system file or file still not found */
   2168     if (fullname == NULL) {
   2169 	/*
   2170 	 * Look for it on the system path
   2171 	 */
   2172 	SearchPath *path = Lst_IsEmpty(sysIncPath) ? defSysIncPath : sysIncPath;
   2173 	fullname = Dir_FindFile(file, path);
   2174     }
   2175 
   2176     if (fullname == NULL) {
   2177 	if (!silent)
   2178 	    Parse_Error(PARSE_FATAL, "Could not find %s", file);
   2179 	return;
   2180     }
   2181 
   2182     /* Actually open the file... */
   2183     fd = open(fullname, O_RDONLY);
   2184     if (fd == -1) {
   2185 	if (!silent)
   2186 	    Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
   2187 	free(fullname);
   2188 	return;
   2189     }
   2190 
   2191     /* load it */
   2192     lf = loadfile(fullname, fd);
   2193 
   2194     /* Start reading from this file next */
   2195     Parse_SetInput(fullname, 0, -1, loadedfile_nextbuf, lf);
   2196     CurFile()->lf = lf;
   2197     if (depinc)
   2198 	doing_depend = depinc;	/* only turn it on */
   2199 }
   2200 
   2201 static void
   2202 ParseDoInclude(char *line)
   2203 {
   2204     char endc;			/* the character which ends the file spec */
   2205     char *cp;			/* current position in file spec */
   2206     Boolean silent = *line != 'i';
   2207     char *file = line + (silent ? 8 : 7);
   2208 
   2209     /* Skip to delimiter character so we know where to look */
   2210     pp_skip_hspace(&file);
   2211 
   2212     if (*file != '"' && *file != '<') {
   2213 	Parse_Error(PARSE_FATAL,
   2214 		    ".include filename must be delimited by '\"' or '<'");
   2215 	return;
   2216     }
   2217 
   2218     /*
   2219      * Set the search path on which to find the include file based on the
   2220      * characters which bracket its name. Angle-brackets imply it's
   2221      * a system Makefile while double-quotes imply it's a user makefile
   2222      */
   2223     if (*file == '<')
   2224 	endc = '>';
   2225     else
   2226 	endc = '"';
   2227 
   2228     /* Skip to matching delimiter */
   2229     for (cp = ++file; *cp && *cp != endc; cp++)
   2230 	continue;
   2231 
   2232     if (*cp != endc) {
   2233 	Parse_Error(PARSE_FATAL,
   2234 		    "Unclosed %cinclude filename. '%c' expected",
   2235 		    '.', endc);
   2236 	return;
   2237     }
   2238 
   2239     *cp = '\0';
   2240 
   2241     /*
   2242      * Substitute for any variables in the file name before trying to
   2243      * find the thing.
   2244      */
   2245     (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &file);
   2246     /* TODO: handle errors */
   2247 
   2248     Parse_include_file(file, endc == '>', *line == 'd', silent);
   2249     free(file);
   2250 }
   2251 
   2252 /* Split filename into dirname + basename, then assign these to the
   2253  * given variables. */
   2254 static void
   2255 SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
   2256 {
   2257     const char *slash, *dirname, *basename;
   2258     void *freeIt;
   2259 
   2260     slash = strrchr(filename, '/');
   2261     if (slash == NULL) {
   2262 	dirname = curdir;
   2263 	basename = filename;
   2264 	freeIt = NULL;
   2265     } else {
   2266 	dirname = freeIt = bmake_strsedup(filename, slash);
   2267 	basename = slash + 1;
   2268     }
   2269 
   2270     Var_Set(dirvar, dirname, VAR_GLOBAL);
   2271     Var_Set(filevar, basename, VAR_GLOBAL);
   2272 
   2273     DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
   2274 	   __func__, dirvar, dirname, filevar, basename);
   2275     free(freeIt);
   2276 }
   2277 
   2278 /* Return the immediately including file.
   2279  *
   2280  * This is made complicated since the .for loop is implemented as a special
   2281  * kind of .include; see For_Run. */
   2282 static const char *
   2283 GetActuallyIncludingFile(void)
   2284 {
   2285     size_t i;
   2286     const IFile *incs = GetInclude(0);
   2287 
   2288     for (i = includes.len; i >= 2; i--)
   2289 	if (!incs[i - 1].fromForLoop)
   2290 	    return incs[i - 2].fname;
   2291     return NULL;
   2292 }
   2293 
   2294 /* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
   2295 static void
   2296 ParseSetParseFile(const char *filename)
   2297 {
   2298     const char *including;
   2299 
   2300     SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");
   2301 
   2302     including = GetActuallyIncludingFile();
   2303     if (including != NULL) {
   2304 	SetFilenameVars(including,
   2305 			".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
   2306     } else {
   2307 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
   2308 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
   2309     }
   2310 }
   2311 
   2312 static Boolean
   2313 StrContainsWord(const char *str, const char *word)
   2314 {
   2315     size_t strLen = strlen(str);
   2316     size_t wordLen = strlen(word);
   2317     const char *p, *end;
   2318 
   2319     if (strLen < wordLen)
   2320 	return FALSE;		/* str is too short to contain word */
   2321 
   2322     end = str + strLen - wordLen;
   2323     for (p = str; p != NULL; p = strchr(p, ' ')) {
   2324 	if (*p == ' ')
   2325 	    p++;
   2326 	if (p > end)
   2327 	    return FALSE;	/* cannot contain word */
   2328 
   2329 	if (memcmp(p, word, wordLen) == 0 &&
   2330 	    (p[wordLen] == '\0' || p[wordLen] == ' '))
   2331 	    return TRUE;
   2332     }
   2333     return FALSE;
   2334 }
   2335 
   2336 /* XXX: Searching through a set of words with this linear search is
   2337  * inefficient for variables that contain thousands of words. */
   2338 static Boolean
   2339 VarContainsWord(const char *varname, const char *word)
   2340 {
   2341     void *val_freeIt;
   2342     const char *val = Var_Value(varname, VAR_GLOBAL, &val_freeIt);
   2343     Boolean found = val != NULL && StrContainsWord(val, word);
   2344     bmake_free(val_freeIt);
   2345     return found;
   2346 }
   2347 
   2348 /* Track the makefiles we read - so makefiles can set dependencies on them.
   2349  * Avoid adding anything more than once. */
   2350 static void
   2351 ParseTrackInput(const char *name)
   2352 {
   2353     if (!VarContainsWord(MAKE_MAKEFILES, name))
   2354 	Var_Append(MAKE_MAKEFILES, name, VAR_GLOBAL);
   2355 }
   2356 
   2357 
   2358 /* Start Parsing from the given source.
   2359  *
   2360  * The given file is added to the includes stack. */
   2361 void
   2362 Parse_SetInput(const char *name, int line, int fd,
   2363 	       char *(*nextbuf)(void *, size_t *), void *arg)
   2364 {
   2365     IFile *curFile;
   2366     char *buf;
   2367     size_t len;
   2368     Boolean fromForLoop = name == NULL;
   2369 
   2370     if (fromForLoop)
   2371 	name = CurFile()->fname;
   2372     else
   2373 	ParseTrackInput(name);
   2374 
   2375     if (DEBUG(PARSE))
   2376 	debug_printf("%s: file %s, line %d, fd %d, nextbuf %s, arg %p\n",
   2377 		     __func__, name, line, fd,
   2378 		     nextbuf == loadedfile_nextbuf ? "loadedfile" : "other",
   2379 		     arg);
   2380 
   2381     if (fd == -1 && nextbuf == NULL)
   2382 	/* sanity */
   2383 	return;
   2384 
   2385     curFile = Vector_Push(&includes);
   2386 
   2387     /*
   2388      * Once the previous state has been saved, we can get down to reading
   2389      * the new file. We set up the name of the file to be the absolute
   2390      * name of the include file so error messages refer to the right
   2391      * place.
   2392      */
   2393     curFile->fname = bmake_strdup(name);
   2394     curFile->fromForLoop = fromForLoop;
   2395     curFile->lineno = line;
   2396     curFile->first_lineno = line;
   2397     curFile->nextbuf = nextbuf;
   2398     curFile->nextbuf_arg = arg;
   2399     curFile->lf = NULL;
   2400     curFile->depending = doing_depend;	/* restore this on EOF */
   2401 
   2402     assert(nextbuf != NULL);
   2403 
   2404     /* Get first block of input data */
   2405     buf = curFile->nextbuf(curFile->nextbuf_arg, &len);
   2406     if (buf == NULL) {
   2407 	/* Was all a waste of time ... */
   2408 	if (curFile->fname)
   2409 	    free(curFile->fname);
   2410 	free(curFile);
   2411 	return;
   2412     }
   2413     curFile->buf_freeIt = buf;
   2414     curFile->buf_ptr = buf;
   2415     curFile->buf_end = buf + len;
   2416 
   2417     curFile->cond_depth = Cond_save_depth();
   2418     ParseSetParseFile(name);
   2419 }
   2420 
   2421 /* Check if the directive is an include directive. */
   2422 static Boolean
   2423 IsInclude(const char *dir, Boolean sysv)
   2424 {
   2425 	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
   2426 		dir++;
   2427 
   2428 	if (strncmp(dir, "include", 7) != 0)
   2429 		return FALSE;
   2430 
   2431 	/* Space is not mandatory for BSD .include */
   2432 	return !sysv || ch_isspace(dir[7]);
   2433 }
   2434 
   2435 
   2436 #ifdef SYSVINCLUDE
   2437 /* Check if the line is a SYSV include directive. */
   2438 static Boolean
   2439 IsSysVInclude(const char *line)
   2440 {
   2441 	const char *p;
   2442 
   2443 	if (!IsInclude(line, TRUE))
   2444 		return FALSE;
   2445 
   2446 	/* Avoid interpreting a dependency line as an include */
   2447 	for (p = line; (p = strchr(p, ':')) != NULL;) {
   2448 
   2449 		/* end of line -> it's a dependency */
   2450 		if (*++p == '\0')
   2451 			return FALSE;
   2452 
   2453 		/* '::' operator or ': ' -> it's a dependency */
   2454 		if (*p == ':' || ch_isspace(*p))
   2455 			return FALSE;
   2456 	}
   2457 	return TRUE;
   2458 }
   2459 
   2460 /* Push to another file.  The line points to the word "include". */
   2461 static void
   2462 ParseTraditionalInclude(char *line)
   2463 {
   2464     char *cp;			/* current position in file spec */
   2465     Boolean done = FALSE;
   2466     Boolean silent = line[0] != 'i';
   2467     char *file = line + (silent ? 8 : 7);
   2468     char *all_files;
   2469 
   2470     DEBUG2(PARSE, "%s: %s\n", __func__, file);
   2471 
   2472     pp_skip_whitespace(&file);
   2473 
   2474     /*
   2475      * Substitute for any variables in the file name before trying to
   2476      * find the thing.
   2477      */
   2478     (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &all_files);
   2479     /* TODO: handle errors */
   2480 
   2481     if (*file == '\0') {
   2482 	Parse_Error(PARSE_FATAL, "Filename missing from \"include\"");
   2483 	goto out;
   2484     }
   2485 
   2486     for (file = all_files; !done; file = cp + 1) {
   2487 	/* Skip to end of line or next whitespace */
   2488 	for (cp = file; *cp && !ch_isspace(*cp); cp++)
   2489 	    continue;
   2490 
   2491 	if (*cp != '\0')
   2492 	    *cp = '\0';
   2493 	else
   2494 	    done = TRUE;
   2495 
   2496 	Parse_include_file(file, FALSE, FALSE, silent);
   2497     }
   2498 out:
   2499     free(all_files);
   2500 }
   2501 #endif
   2502 
   2503 #ifdef GMAKEEXPORT
   2504 /* Parse "export <variable>=<value>", and actually export it. */
   2505 static void
   2506 ParseGmakeExport(char *line)
   2507 {
   2508     char *variable = line + 6;
   2509     char *value;
   2510 
   2511     DEBUG2(PARSE, "%s: %s\n", __func__, variable);
   2512 
   2513     pp_skip_whitespace(&variable);
   2514 
   2515     for (value = variable; *value && *value != '='; value++)
   2516 	continue;
   2517 
   2518     if (*value != '=') {
   2519 	Parse_Error(PARSE_FATAL,
   2520 		    "Variable/Value missing from \"export\"");
   2521 	return;
   2522     }
   2523     *value++ = '\0';		/* terminate variable */
   2524 
   2525     /*
   2526      * Expand the value before putting it in the environment.
   2527      */
   2528     (void)Var_Subst(value, VAR_CMDLINE, VARE_WANTRES, &value);
   2529     /* TODO: handle errors */
   2530 
   2531     setenv(variable, value, 1);
   2532     free(value);
   2533 }
   2534 #endif
   2535 
   2536 /* Called when EOF is reached in the current file. If we were reading an
   2537  * include file, the includes stack is popped and things set up to go back
   2538  * to reading the previous file at the previous location.
   2539  *
   2540  * Results:
   2541  *	TRUE to continue parsing, i.e. it had only reached the end of an
   2542  *	included file, FALSE if the main file has been parsed completely.
   2543  */
   2544 static Boolean
   2545 ParseEOF(void)
   2546 {
   2547     char *ptr;
   2548     size_t len;
   2549     IFile *curFile = CurFile();
   2550 
   2551     assert(curFile->nextbuf != NULL);
   2552 
   2553     doing_depend = curFile->depending;	/* restore this */
   2554     /* get next input buffer, if any */
   2555     ptr = curFile->nextbuf(curFile->nextbuf_arg, &len);
   2556     curFile->buf_ptr = ptr;
   2557     curFile->buf_freeIt = ptr;
   2558     curFile->buf_end = ptr + len;
   2559     curFile->lineno = curFile->first_lineno;
   2560     if (ptr != NULL)
   2561 	return TRUE;		/* Iterate again */
   2562 
   2563     /* Ensure the makefile (or loop) didn't have mismatched conditionals */
   2564     Cond_restore_depth(curFile->cond_depth);
   2565 
   2566     if (curFile->lf != NULL) {
   2567 	loadedfile_destroy(curFile->lf);
   2568 	curFile->lf = NULL;
   2569     }
   2570 
   2571     /* Dispose of curFile info */
   2572     /* Leak curFile->fname because all the gnodes have pointers to it */
   2573     free(curFile->buf_freeIt);
   2574     Vector_Pop(&includes);
   2575 
   2576     if (includes.len == 0) {
   2577 	/* We've run out of input */
   2578 	Var_Delete(".PARSEDIR", VAR_GLOBAL);
   2579 	Var_Delete(".PARSEFILE", VAR_GLOBAL);
   2580 	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
   2581 	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
   2582 	return FALSE;
   2583     }
   2584 
   2585     curFile = CurFile();
   2586     DEBUG2(PARSE, "ParseEOF: returning to file %s, line %d\n",
   2587 	   curFile->fname, curFile->lineno);
   2588 
   2589     ParseSetParseFile(curFile->fname);
   2590     return TRUE;
   2591 }
   2592 
   2593 #define PARSE_RAW 1
   2594 #define PARSE_SKIP 2
   2595 
   2596 static char *
   2597 ParseGetLine(int flags)
   2598 {
   2599     IFile *cf = CurFile();
   2600     char *ptr;
   2601     char ch;
   2602     char *line;
   2603     char *line_end;
   2604     char *escaped;
   2605     char *comment;
   2606     char *tp;
   2607 
   2608     /* Loop through blank lines and comment lines */
   2609     for (;;) {
   2610 	cf->lineno++;
   2611 	line = cf->buf_ptr;
   2612 	ptr = line;
   2613 	line_end = line;
   2614 	escaped = NULL;
   2615 	comment = NULL;
   2616 	for (;;) {
   2617 	    /* XXX: can buf_end ever be null? */
   2618 	    if (cf->buf_end != NULL && ptr == cf->buf_end) {
   2619 		/* end of buffer */
   2620 		ch = '\0';
   2621 		break;
   2622 	    }
   2623 	    ch = *ptr;
   2624 	    if (ch == '\0' || (ch == '\\' && ptr[1] == '\0')) {
   2625 		/* XXX: can buf_end ever be null? */
   2626 		if (cf->buf_end == NULL)
   2627 		    /* End of string (aka for loop) data */
   2628 		    break;
   2629 		/* see if there is more we can parse */
   2630 		while (ptr++ < cf->buf_end) {
   2631 		    if ((ch = *ptr) == '\n') {
   2632 			if (ptr > line && ptr[-1] == '\\')
   2633 			    continue;
   2634 			Parse_Error(PARSE_WARNING,
   2635 				    "Zero byte read from file, "
   2636 				    "skipping rest of line.");
   2637 			break;
   2638 		    }
   2639 		}
   2640 		if (cf->nextbuf != NULL) {
   2641 		    /*
   2642 		     * End of this buffer; return EOF and outer logic
   2643 		     * will get the next one. (eww)
   2644 		     */
   2645 		    break;
   2646 		}
   2647 		Parse_Error(PARSE_FATAL, "Zero byte read from file");
   2648 		return NULL;
   2649 	    }
   2650 
   2651 	    if (ch == '\\') {
   2652 		/* Don't treat next character as special, remember first one */
   2653 		if (escaped == NULL)
   2654 		    escaped = ptr;
   2655 		if (ptr[1] == '\n')
   2656 		    cf->lineno++;
   2657 		ptr += 2;
   2658 		line_end = ptr;
   2659 		continue;
   2660 	    }
   2661 	    if (ch == '#' && comment == NULL) {
   2662 		/* Remember first '#' for comment stripping */
   2663 		/* Unless previous char was '[', as in modifier :[#] */
   2664 		if (!(ptr > line && ptr[-1] == '['))
   2665 		    comment = line_end;
   2666 	    }
   2667 	    ptr++;
   2668 	    if (ch == '\n')
   2669 		break;
   2670 	    if (!ch_isspace(ch))
   2671 		/* We are not interested in trailing whitespace */
   2672 		line_end = ptr;
   2673 	}
   2674 
   2675 	/* Save next 'to be processed' location */
   2676 	cf->buf_ptr = ptr;
   2677 
   2678 	/* Check we have a non-comment, non-blank line */
   2679 	if (line_end == line || comment == line) {
   2680 	    if (ch == '\0')
   2681 		/* At end of file */
   2682 		return NULL;
   2683 	    /* Parse another line */
   2684 	    continue;
   2685 	}
   2686 
   2687 	/* We now have a line of data */
   2688 	*line_end = '\0';
   2689 
   2690 	if (flags & PARSE_RAW) {
   2691 	    /* Leave '\' (etc) in line buffer (eg 'for' lines) */
   2692 	    return line;
   2693 	}
   2694 
   2695 	if (flags & PARSE_SKIP) {
   2696 	    /* Completely ignore non-directives */
   2697 	    if (line[0] != '.')
   2698 		continue;
   2699 	    /* We could do more of the .else/.elif/.endif checks here */
   2700 	}
   2701 	break;
   2702     }
   2703 
   2704     /* Brutally ignore anything after a non-escaped '#' in non-commands */
   2705     if (comment != NULL && line[0] != '\t') {
   2706 	line_end = comment;
   2707 	*line_end = '\0';
   2708     }
   2709 
   2710     /* If we didn't see a '\\' then the in-situ data is fine */
   2711     if (escaped == NULL)
   2712 	return line;
   2713 
   2714     /* Remove escapes from '\n' and '#' */
   2715     tp = ptr = escaped;
   2716     escaped = line;
   2717     for (; ; *tp++ = ch) {
   2718 	ch = *ptr++;
   2719 	if (ch != '\\') {
   2720 	    if (ch == '\0')
   2721 		break;
   2722 	    continue;
   2723 	}
   2724 
   2725 	ch = *ptr++;
   2726 	if (ch == '\0') {
   2727 	    /* Delete '\\' at end of buffer */
   2728 	    tp--;
   2729 	    break;
   2730 	}
   2731 
   2732 	if (ch == '#' && line[0] != '\t')
   2733 	    /* Delete '\\' from before '#' on non-command lines */
   2734 	    continue;
   2735 
   2736 	if (ch != '\n') {
   2737 	    /* Leave '\\' in buffer for later */
   2738 	    *tp++ = '\\';
   2739 	    /* Make sure we don't delete an escaped ' ' from the line end */
   2740 	    escaped = tp + 1;
   2741 	    continue;
   2742 	}
   2743 
   2744 	/* Escaped '\n' -- replace following whitespace with a single ' '. */
   2745 	pp_skip_hspace(&ptr);
   2746 	ch = ' ';
   2747     }
   2748 
   2749     /* Delete any trailing spaces - eg from empty continuations */
   2750     while (tp > escaped && ch_isspace(tp[-1]))
   2751 	tp--;
   2752 
   2753     *tp = '\0';
   2754     return line;
   2755 }
   2756 
   2757 /* Read an entire line from the input file. Called only by Parse_File.
   2758  *
   2759  * Results:
   2760  *	A line without its newline.
   2761  *
   2762  * Side Effects:
   2763  *	Only those associated with reading a character
   2764  */
   2765 static char *
   2766 ParseReadLine(void)
   2767 {
   2768     char *line;			/* Result */
   2769     int lineno;			/* Saved line # */
   2770     int rval;
   2771 
   2772     for (;;) {
   2773 	line = ParseGetLine(0);
   2774 	if (line == NULL)
   2775 	    return NULL;
   2776 
   2777 	if (line[0] != '.')
   2778 	    return line;
   2779 
   2780 	/*
   2781 	 * The line might be a conditional. Ask the conditional module
   2782 	 * about it and act accordingly
   2783 	 */
   2784 	switch (Cond_EvalLine(line)) {
   2785 	case COND_SKIP:
   2786 	    /* Skip to next conditional that evaluates to COND_PARSE.  */
   2787 	    do {
   2788 		line = ParseGetLine(PARSE_SKIP);
   2789 	    } while (line && Cond_EvalLine(line) != COND_PARSE);
   2790 	    if (line == NULL)
   2791 		break;
   2792 	    continue;
   2793 	case COND_PARSE:
   2794 	    continue;
   2795 	case COND_INVALID:    /* Not a conditional line */
   2796 	    /* Check for .for loops */
   2797 	    rval = For_Eval(line);
   2798 	    if (rval == 0)
   2799 		/* Not a .for line */
   2800 		break;
   2801 	    if (rval < 0)
   2802 		/* Syntax error - error printed, ignore line */
   2803 		continue;
   2804 	    /* Start of a .for loop */
   2805 	    lineno = CurFile()->lineno;
   2806 	    /* Accumulate loop lines until matching .endfor */
   2807 	    do {
   2808 		line = ParseGetLine(PARSE_RAW);
   2809 		if (line == NULL) {
   2810 		    Parse_Error(PARSE_FATAL,
   2811 				"Unexpected end of file in for loop.");
   2812 		    break;
   2813 		}
   2814 	    } while (For_Accum(line));
   2815 	    /* Stash each iteration as a new 'input file' */
   2816 	    For_Run(lineno);
   2817 	    /* Read next line from for-loop buffer */
   2818 	    continue;
   2819 	}
   2820 	return line;
   2821     }
   2822 }
   2823 
   2824 static void
   2825 FinishDependencyGroup(void)
   2826 {
   2827     GNodeListNode *ln;
   2828 
   2829     if (targets == NULL)
   2830 	return;
   2831 
   2832     for (ln = targets->first; ln != NULL; ln = ln->next) {
   2833 	GNode *gn = ln->datum;
   2834 
   2835 	Suff_EndTransform(gn);
   2836 
   2837 	/* Mark the target as already having commands if it does, to
   2838 	 * keep from having shell commands on multiple dependency lines. */
   2839 	if (!Lst_IsEmpty(gn->commands))
   2840 	    gn->type |= OP_HAS_COMMANDS;
   2841     }
   2842 
   2843     Lst_Free(targets);
   2844     targets = NULL;
   2845 }
   2846 
   2847 /* Add the command to each target from the current dependency spec. */
   2848 static void
   2849 ParseLine_ShellCommand(const char *p)
   2850 {
   2851     cpp_skip_whitespace(&p);
   2852     if (*p == '\0')
   2853 	return;			/* skip empty commands */
   2854 
   2855     if (targets == NULL) {
   2856 	Parse_Error(PARSE_FATAL, "Unassociated shell command \"%s\"", p);
   2857 	return;
   2858     }
   2859 
   2860     {
   2861 	char *cmd = bmake_strdup(p);
   2862 	GNodeListNode *ln;
   2863 
   2864 	for (ln = targets->first; ln != NULL; ln = ln->next) {
   2865 	    GNode *gn = ln->datum;
   2866 	    ParseAddCmd(gn, cmd);
   2867 	}
   2868 #ifdef CLEANUP
   2869 	Lst_Append(targCmds, cmd);
   2870 #endif
   2871     }
   2872 }
   2873 
   2874 static Boolean
   2875 ParseDirective(char *line)
   2876 {
   2877     char *cp;
   2878 
   2879     if (*line == '.') {
   2880 	/*
   2881 	 * Lines that begin with the special character may be
   2882 	 * include or undef directives.
   2883 	 * On the other hand they can be suffix rules (.c.o: ...)
   2884 	 * or just dependencies for filenames that start '.'.
   2885 	 */
   2886 	cp = line + 1;
   2887 	pp_skip_whitespace(&cp);
   2888 	if (IsInclude(cp, FALSE)) {
   2889 	    ParseDoInclude(cp);
   2890 	    return TRUE;
   2891 	}
   2892 	if (strncmp(cp, "undef", 5) == 0) {
   2893 	    const char *varname;
   2894 	    cp += 5;
   2895 	    pp_skip_whitespace(&cp);
   2896 	    varname = cp;
   2897 	    for (; !ch_isspace(*cp) && *cp != '\0'; cp++)
   2898 		continue;
   2899 	    *cp = '\0';
   2900 	    Var_Delete(varname, VAR_GLOBAL);
   2901 	    /* TODO: undefine all variables, not only the first */
   2902 	    /* TODO: use Str_Words, like everywhere else */
   2903 	    return TRUE;
   2904 	} else if (strncmp(cp, "export", 6) == 0) {
   2905 	    cp += 6;
   2906 	    pp_skip_whitespace(&cp);
   2907 	    Var_Export(cp, TRUE);
   2908 	    return TRUE;
   2909 	} else if (strncmp(cp, "unexport", 8) == 0) {
   2910 	    Var_UnExport(cp);
   2911 	    return TRUE;
   2912 	} else if (strncmp(cp, "info", 4) == 0 ||
   2913 		   strncmp(cp, "error", 5) == 0 ||
   2914 		   strncmp(cp, "warning", 7) == 0) {
   2915 	    if (ParseMessage(cp))
   2916 		return TRUE;
   2917 	}
   2918     }
   2919     return FALSE;
   2920 }
   2921 
   2922 static Boolean
   2923 ParseVarassign(const char *line)
   2924 {
   2925     VarAssign var;
   2926 
   2927     if (!Parse_IsVar(line, &var))
   2928 	return FALSE;
   2929 
   2930     FinishDependencyGroup();
   2931     Parse_DoVar(&var, VAR_GLOBAL);
   2932     return TRUE;
   2933 }
   2934 
   2935 static char *
   2936 FindSemicolon(char *p)
   2937 {
   2938     int level = 0;
   2939 
   2940     for (; *p != '\0'; p++) {
   2941 	if (*p == '\\' && p[1] != '\0') {
   2942 	    p++;
   2943 	    continue;
   2944 	}
   2945 
   2946 	if (*p == '$' && (p[1] == '(' || p[1] == '{'))
   2947 	    level++;
   2948 	else if (level > 0 && (*p == ')' || *p == '}'))
   2949 	    level--;
   2950 	else if (level == 0 && *p == ';')
   2951 	    break;
   2952     }
   2953     return p;
   2954 }
   2955 
   2956 /* dependency	-> target... op [source...]
   2957  * op		-> ':' | '::' | '!' */
   2958 static void
   2959 ParseDependency(char *line)
   2960 {
   2961     VarEvalFlags eflags;
   2962     char *expanded_line;
   2963     const char *shellcmd = NULL;
   2964 
   2965     /*
   2966      * For some reason - probably to make the parser impossible -
   2967      * a ';' can be used to separate commands from dependencies.
   2968      * Attempt to avoid ';' inside substitution patterns.
   2969      */
   2970     {
   2971 	char *semicolon = FindSemicolon(line);
   2972 	if (*semicolon != '\0') {
   2973 	    /* Terminate the dependency list at the ';' */
   2974 	    *semicolon = '\0';
   2975 	    shellcmd = semicolon + 1;
   2976 	}
   2977     }
   2978 
   2979     /*
   2980      * We now know it's a dependency line so it needs to have all
   2981      * variables expanded before being parsed.
   2982      *
   2983      * XXX: Ideally the dependency line would first be split into
   2984      * its left-hand side, dependency operator and right-hand side,
   2985      * and then each side would be expanded on its own.  This would
   2986      * allow for the left-hand side to allow only defined variables
   2987      * and to allow variables on the right-hand side to be undefined
   2988      * as well.
   2989      *
   2990      * Parsing the line first would also prevent that targets
   2991      * generated from variable expressions are interpreted as the
   2992      * dependency operator, such as in "target${:U:} middle: source",
   2993      * in which the middle is interpreted as a source, not a target.
   2994      */
   2995 
   2996     /* In lint mode, allow undefined variables to appear in
   2997      * dependency lines.
   2998      *
   2999      * Ideally, only the right-hand side would allow undefined
   3000      * variables since it is common to have no dependencies.
   3001      * Having undefined variables on the left-hand side is more
   3002      * unusual though.  Since both sides are expanded in a single
   3003      * pass, there is not much choice what to do here.
   3004      *
   3005      * In normal mode, it does not matter whether undefined
   3006      * variables are allowed or not since as of 2020-09-14,
   3007      * Var_Parse does not print any parse errors in such a case.
   3008      * It simply returns the special empty string var_Error,
   3009      * which cannot be detected in the result of Var_Subst. */
   3010     eflags = opts.lint ? VARE_WANTRES : VARE_WANTRES | VARE_UNDEFERR;
   3011     (void)Var_Subst(line, VAR_CMDLINE, eflags, &expanded_line);
   3012     /* TODO: handle errors */
   3013 
   3014     /* Need a fresh list for the target nodes */
   3015     if (targets != NULL)
   3016 	Lst_Free(targets);
   3017     targets = Lst_New();
   3018 
   3019     ParseDoDependency(expanded_line);
   3020     free(expanded_line);
   3021 
   3022     if (shellcmd != NULL)
   3023 	ParseLine_ShellCommand(shellcmd);
   3024 }
   3025 
   3026 static void
   3027 ParseLine(char *line)
   3028 {
   3029     if (ParseDirective(line))
   3030 	return;
   3031 
   3032     if (*line == '\t') {
   3033 	ParseLine_ShellCommand(line + 1);
   3034 	return;
   3035     }
   3036 
   3037 #ifdef SYSVINCLUDE
   3038     if (IsSysVInclude(line)) {
   3039 	/*
   3040 	 * It's an S3/S5-style "include".
   3041 	 */
   3042 	ParseTraditionalInclude(line);
   3043 	return;
   3044     }
   3045 #endif
   3046 
   3047 #ifdef GMAKEEXPORT
   3048     if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
   3049 	strchr(line, ':') == NULL) {
   3050 	/*
   3051 	 * It's a Gmake "export".
   3052 	 */
   3053 	ParseGmakeExport(line);
   3054 	return;
   3055     }
   3056 #endif
   3057 
   3058     if (ParseVarassign(line))
   3059 	return;
   3060 
   3061     FinishDependencyGroup();
   3062 
   3063     ParseDependency(line);
   3064 }
   3065 
   3066 /* Parse a top-level makefile into its component parts, incorporating them
   3067  * into the global dependency graph.
   3068  *
   3069  * Input:
   3070  *	name		The name of the file being read
   3071  *	fd		The open file to parse; will be closed at the end
   3072  */
   3073 void
   3074 Parse_File(const char *name, int fd)
   3075 {
   3076     char *line;			/* the line we're working on */
   3077     struct loadedfile *lf;
   3078 
   3079     lf = loadfile(name, fd);
   3080 
   3081     assert(targets == NULL);
   3082     fatals = 0;
   3083 
   3084     if (name == NULL)
   3085 	name = "(stdin)";
   3086 
   3087     Parse_SetInput(name, 0, -1, loadedfile_nextbuf, lf);
   3088     CurFile()->lf = lf;
   3089 
   3090     do {
   3091 	while ((line = ParseReadLine()) != NULL) {
   3092 	    DEBUG2(PARSE, "ParseReadLine (%d): '%s'\n",
   3093 		   CurFile()->lineno, line);
   3094 	    ParseLine(line);
   3095 	}
   3096 	/*
   3097 	 * Reached EOF, but it may be just EOF of an include file...
   3098 	 */
   3099     } while (ParseEOF());
   3100 
   3101     FinishDependencyGroup();
   3102 
   3103     if (fatals != 0) {
   3104 	(void)fflush(stdout);
   3105 	(void)fprintf(stderr,
   3106 		      "%s: Fatal errors encountered -- cannot continue",
   3107 		      progname);
   3108 	PrintOnError(NULL, NULL);
   3109 	exit(1);
   3110     }
   3111 }
   3112 
   3113 /* Initialize the parsing module. */
   3114 void
   3115 Parse_Init(void)
   3116 {
   3117     mainNode = NULL;
   3118     parseIncPath = Lst_New();
   3119     sysIncPath = Lst_New();
   3120     defSysIncPath = Lst_New();
   3121     Vector_Init(&includes, sizeof(IFile));
   3122 #ifdef CLEANUP
   3123     targCmds = Lst_New();
   3124 #endif
   3125 }
   3126 
   3127 /* Clean up the parsing module. */
   3128 void
   3129 Parse_End(void)
   3130 {
   3131 #ifdef CLEANUP
   3132     Lst_Destroy(targCmds, free);
   3133     assert(targets == NULL);
   3134     Lst_Destroy(defSysIncPath, Dir_Destroy);
   3135     Lst_Destroy(sysIncPath, Dir_Destroy);
   3136     Lst_Destroy(parseIncPath, Dir_Destroy);
   3137     assert(includes.len == 0);
   3138     Vector_Done(&includes);
   3139 #endif
   3140 }
   3141 
   3142 
   3143 /*-
   3144  *-----------------------------------------------------------------------
   3145  * Parse_MainName --
   3146  *	Return a Lst of the main target to create for main()'s sake. If
   3147  *	no such target exists, we Punt with an obnoxious error message.
   3148  *
   3149  * Results:
   3150  *	A Lst of the single node to create.
   3151  *
   3152  * Side Effects:
   3153  *	None.
   3154  *
   3155  *-----------------------------------------------------------------------
   3156  */
   3157 GNodeList *
   3158 Parse_MainName(void)
   3159 {
   3160     GNodeList *mainList;
   3161 
   3162     mainList = Lst_New();
   3163 
   3164     if (mainNode == NULL)
   3165 	Punt("no target to make.");
   3166 
   3167     if (mainNode->type & OP_DOUBLEDEP) {
   3168 	Lst_Append(mainList, mainNode);
   3169 	Lst_AppendAll(mainList, mainNode->cohorts);
   3170     } else
   3171 	Lst_Append(mainList, mainNode);
   3172     Var_Append(".TARGETS", mainNode->name, VAR_GLOBAL);
   3173     return mainList;
   3174 }
   3175 
   3176 int
   3177 Parse_GetFatals(void)
   3178 {
   3179     return fatals;
   3180 }
   3181