xref: /src/usr.bin/make/parse.c

/*	$NetBSD: parse.c,v 1.461 2020/11/29 00:04:22 rillig Exp $	*/

/*
 * Copyright (c) 1988, 1989, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Adam de Boor.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Copyright (c) 1989 by Berkeley Softworks
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Adam de Boor.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Parsing of makefiles.
 *
 * Parse_File is the main entry point and controls most of the other
 * functions in this module.
 *
 * The directories for the .include "..." directive are kept in
 * 'parseIncPath', while those for .include <...> are kept in 'sysIncPath'.
 * The targets currently being defined are kept in 'targets'.
 *
 * Interface:
 *	Parse_Init	Initialize the module
 *
 *	Parse_End	Clean up the module
 *
 *	Parse_File	Parse a top-level makefile.  Included files are
 *			handled by Parse_include_file though.
 *
 *	Parse_IsVar	Return TRUE if the given line is a variable
 *			assignment. Used by MainParseArgs to determine if
 *			an argument is a target or a variable assignment.
 *			Used internally for pretty much the same thing.
 *
 *	Parse_Error	Report a parse error, a warning or an informational
 *			message.
 *
 *	Parse_MainName	Returns a list of the main target to create.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdarg.h>
#include <stdint.h>

#ifndef MAP_FILE
#define MAP_FILE 0
#endif
#ifndef MAP_COPY
#define MAP_COPY MAP_PRIVATE
#endif

#include "make.h"
#include "dir.h"
#include "job.h"
#include "pathnames.h"

/*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
MAKE_RCSID("$NetBSD: parse.c,v 1.461 2020/11/29 00:04:22 rillig Exp $");

/* types and constants */

/*
 * Structure for a file being read ("included file")
 */
typedef struct IFile {
    char *fname;		/* name of file (relative? absolute?) */
    Boolean fromForLoop;	/* simulated .include by the .for loop */
    int lineno;			/* current line number in file */
    int first_lineno;		/* line number of start of text */
    unsigned int cond_depth;	/* 'if' nesting when file opened */
    Boolean depending;		/* state of doing_depend on EOF */

    /* The buffer from which the file's content is read. */
    char *buf_freeIt;
    char *buf_ptr;		/* next char to be read */
    char *buf_end;

    char *(*nextbuf)(void *, size_t *); /* Function to get more data */
    void *nextbuf_arg;		/* Opaque arg for nextbuf() */
    struct loadedfile *lf;	/* loadedfile object, if any */
} IFile;

/*
 * Tokens for target attributes
 */
typedef enum ParseSpecial {
    SP_ATTRIBUTE,	/* Generic attribute */
    SP_BEGIN,		/* .BEGIN */
    SP_DEFAULT,		/* .DEFAULT */
    SP_DELETE_ON_ERROR,	/* .DELETE_ON_ERROR */
    SP_END,		/* .END */
    SP_ERROR,		/* .ERROR */
    SP_IGNORE,		/* .IGNORE */
    SP_INCLUDES,	/* .INCLUDES; not mentioned in the manual page */
    SP_INTERRUPT,	/* .INTERRUPT */
    SP_LIBS,		/* .LIBS; not mentioned in the manual page */
    SP_MAIN,		/* .MAIN and we don't have anything user-specified to
			 * make */
    SP_META,		/* .META */
    SP_MFLAGS,		/* .MFLAGS or .MAKEFLAGS */
    SP_NOMETA,		/* .NOMETA */
    SP_NOMETA_CMP,	/* .NOMETA_CMP */
    SP_NOPATH,		/* .NOPATH */
    SP_NOT,		/* Not special */
    SP_NOTPARALLEL,	/* .NOTPARALLEL or .NO_PARALLEL */
    SP_NULL,		/* .NULL; not mentioned in the manual page */
    SP_OBJDIR,		/* .OBJDIR */
    SP_ORDER,		/* .ORDER */
    SP_PARALLEL,	/* .PARALLEL; not mentioned in the manual page */
    SP_PATH,		/* .PATH or .PATH.suffix */
    SP_PHONY,		/* .PHONY */
#ifdef POSIX
    SP_POSIX,		/* .POSIX; not mentioned in the manual page */
#endif
    SP_PRECIOUS,	/* .PRECIOUS */
    SP_SHELL,		/* .SHELL */
    SP_SILENT,		/* .SILENT */
    SP_SINGLESHELL,	/* .SINGLESHELL; not mentioned in the manual page */
    SP_STALE,		/* .STALE */
    SP_SUFFIXES,	/* .SUFFIXES */
    SP_WAIT		/* .WAIT */
} ParseSpecial;

typedef List SearchPathList;
typedef ListNode SearchPathListNode;

/* result data */

/*
 * The main target to create. This is the first target on the first
 * dependency line in the first makefile.
 */
static GNode *mainNode;

/* eval state */

/* During parsing, the targets from the left-hand side of the currently
 * active dependency line, or NULL if the current line does not belong to a
 * dependency line, for example because it is a variable assignment.
 *
 * See unit-tests/deptgt.mk, keyword "parse.c:targets". */
static GNodeList *targets;

#ifdef CLEANUP
/* All shell commands for all targets, in no particular order and possibly
 * with duplicates.  Kept in a separate list since the commands from .USE or
 * .USEBEFORE nodes are shared with other GNodes, thereby giving up the
 * easily understandable ownership over the allocated strings. */
static StringList targCmds = LST_INIT;
#endif

/*
 * Predecessor node for handling .ORDER. Initialized to NULL when .ORDER
 * seen, then set to each successive source on the line.
 */
static GNode *order_pred;

/* parser state */

/* number of fatal errors */
static int fatals = 0;

/*
 * Variables for doing includes
 */

/* The include chain of makefiles.  At the bottom is the top-level makefile
 * from the command line, and on top of that, there are the included files or
 * .for loops, up to and including the current file.
 *
 * This data could be used to print stack traces on parse errors.  As of
 * 2020-09-14, this is not done though.  It seems quite simple to print the
 * tuples (fname:lineno:fromForLoop), from top to bottom.  This simple idea is
 * made complicated by the fact that the .for loops also use this stack for
 * storing information.
 *
 * The lineno fields of the IFiles with fromForLoop == TRUE look confusing,
 * which is demonstrated by the test 'include-main.mk'.  They seem sorted
 * backwards since they tell the number of completely parsed lines, which for
 * a .for loop is right after the terminating .endfor.  To compensate for this
 * confusion, there is another field first_lineno pointing at the start of the
 * .for loop, 1-based for human consumption.
 *
 * To make the stack trace intuitive, the entry below the first .for loop must
 * be ignored completely since neither its lineno nor its first_lineno is
 * useful.  Instead, the topmost of each chain of .for loop needs to be
 * printed twice, once with its first_lineno and once with its lineno.
 *
 * As of 2020-10-28, using the above rules, the stack trace for the .info line
 * in include-subsub.mk would be:
 *
 *	includes[5]:	include-subsub.mk:4
 *			(lineno, from an .include)
 *	includes[4]:	include-sub.mk:32
 *			(lineno, from a .for loop below an .include)
 *	includes[4]:	include-sub.mk:31
 *			(first_lineno, from a .for loop, lineno == 32)
 *	includes[3]:	include-sub.mk:30
 *			(first_lineno, from a .for loop, lineno == 33)
 *	includes[2]:	include-sub.mk:29
 *			(first_lineno, from a .for loop, lineno == 34)
 *	includes[1]:	include-sub.mk:35
 *			(not printed since it is below a .for loop)
 *	includes[0]:	include-main.mk:27
 */
static Vector /* of IFile */ includes;

static IFile *
GetInclude(size_t i)
{
    return Vector_Get(&includes, i);
}

/* The file that is currently being read. */
static IFile *
CurFile(void)
{
    return GetInclude(includes.len - 1);
}

/* include paths */
SearchPath *parseIncPath;	/* dirs for "..." includes */
SearchPath *sysIncPath;		/* dirs for <...> includes */
SearchPath *defSysIncPath;	/* default for sysIncPath */

/* parser tables */

/*
 * The parseKeywords table is searched using binary search when deciding
 * if a target or source is special. The 'spec' field is the ParseSpecial
 * type of the keyword (SP_NOT if the keyword isn't special as a target) while
 * the 'op' field is the operator to apply to the list of targets if the
 * keyword is used as a source ("0" if the keyword isn't special as a source)
 */
static const struct {
    const char   *name;		/* Name of keyword */
    ParseSpecial  spec;		/* Type when used as a target */
    GNodeType	  op;		/* Operator when used as a source */
} parseKeywords[] = {
    { ".BEGIN",		SP_BEGIN,	0 },
    { ".DEFAULT",	SP_DEFAULT,	0 },
    { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, 0 },
    { ".END",		SP_END,		0 },
    { ".ERROR",		SP_ERROR,	0 },
    { ".EXEC",		SP_ATTRIBUTE,	OP_EXEC },
    { ".IGNORE",	SP_IGNORE,	OP_IGNORE },
    { ".INCLUDES",	SP_INCLUDES,	0 },
    { ".INTERRUPT",	SP_INTERRUPT,	0 },
    { ".INVISIBLE",	SP_ATTRIBUTE,	OP_INVISIBLE },
    { ".JOIN",		SP_ATTRIBUTE,	OP_JOIN },
    { ".LIBS",		SP_LIBS,	0 },
    { ".MADE",		SP_ATTRIBUTE,	OP_MADE },
    { ".MAIN",		SP_MAIN,	0 },
    { ".MAKE",		SP_ATTRIBUTE,	OP_MAKE },
    { ".MAKEFLAGS",	SP_MFLAGS,	0 },
    { ".META",		SP_META,	OP_META },
    { ".MFLAGS",	SP_MFLAGS,	0 },
    { ".NOMETA",	SP_NOMETA,	OP_NOMETA },
    { ".NOMETA_CMP",	SP_NOMETA_CMP,	OP_NOMETA_CMP },
    { ".NOPATH",	SP_NOPATH,	OP_NOPATH },
    { ".NOTMAIN",	SP_ATTRIBUTE,	OP_NOTMAIN },
    { ".NOTPARALLEL",	SP_NOTPARALLEL,	0 },
    { ".NO_PARALLEL",	SP_NOTPARALLEL,	0 },
    { ".NULL",		SP_NULL,	0 },
    { ".OBJDIR",	SP_OBJDIR,	0 },
    { ".OPTIONAL",	SP_ATTRIBUTE,	OP_OPTIONAL },
    { ".ORDER",		SP_ORDER,	0 },
    { ".PARALLEL",	SP_PARALLEL,	0 },
    { ".PATH",		SP_PATH,	0 },
    { ".PHONY",		SP_PHONY,	OP_PHONY },
#ifdef POSIX
    { ".POSIX",		SP_POSIX,	0 },
#endif
    { ".PRECIOUS",	SP_PRECIOUS,	OP_PRECIOUS },
    { ".RECURSIVE",	SP_ATTRIBUTE,	OP_MAKE },
    { ".SHELL",		SP_SHELL,	0 },
    { ".SILENT",	SP_SILENT,	OP_SILENT },
    { ".SINGLESHELL",	SP_SINGLESHELL,	0 },
    { ".STALE",		SP_STALE,	0 },
    { ".SUFFIXES",	SP_SUFFIXES,	0 },
    { ".USE",		SP_ATTRIBUTE,	OP_USE },
    { ".USEBEFORE",	SP_ATTRIBUTE,	OP_USEBEFORE },
    { ".WAIT",		SP_WAIT,	0 },
};

/* file loader */

struct loadedfile {
	/* XXX: What is the lifetime of this path? Who manages the memory? */
	const char *path;		/* name, for error reports */
	char *buf;			/* contents buffer */
	size_t len;			/* length of contents */
	size_t maplen;			/* length of mmap area, or 0 */
	Boolean used;			/* XXX: have we used the data yet */
};

/* XXX: What is the lifetime of the path? Who manages the memory? */
static struct loadedfile *
loadedfile_create(const char *path)
{
	struct loadedfile *lf;

	lf = bmake_malloc(sizeof *lf);
	lf->path = path == NULL ? "(stdin)" : path;
	lf->buf = NULL;
	lf->len = 0;
	lf->maplen = 0;
	lf->used = FALSE;
	return lf;
}

static void
loadedfile_destroy(struct loadedfile *lf)
{
	if (lf->buf != NULL) {
		if (lf->maplen > 0)
			munmap(lf->buf, lf->maplen);
		else
			free(lf->buf);
	}
	free(lf);
}

/*
 * nextbuf() operation for loadedfile, as needed by the weird and twisted
 * logic below. Once that's cleaned up, we can get rid of lf->used...
 */
static char *
loadedfile_nextbuf(void *x, size_t *len)
{
	struct loadedfile *lf = x;

	if (lf->used)
		return NULL;

	lf->used = TRUE;
	*len = lf->len;
	return lf->buf;
}

/*
 * Try to get the size of a file.
 */
static Boolean
load_getsize(int fd, size_t *ret)
{
	struct stat st;

	if (fstat(fd, &st) < 0)
		return FALSE;

	if (!S_ISREG(st.st_mode))
		return FALSE;

	/*
	 * st_size is an off_t, which is 64 bits signed; *ret is
	 * size_t, which might be 32 bits unsigned or 64 bits
	 * unsigned. Rather than being elaborate, just punt on
	 * files that are more than 2^31 bytes. We should never
	 * see a makefile that size in practice...
	 *
	 * While we're at it reject negative sizes too, just in case.
	 */
	if (st.st_size < 0 || st.st_size > 0x7fffffff)
		return FALSE;

	*ret = (size_t)st.st_size;
	return TRUE;
}

static Boolean
loadedfile_mmap(struct loadedfile *lf, int fd)
{
	static unsigned long pagesize = 0;

	if (!load_getsize(fd, &lf->len))
		return FALSE;

	/* found a size, try mmap */
	if (pagesize == 0)
		pagesize = (unsigned long)sysconf(_SC_PAGESIZE);
	if (pagesize == 0 || pagesize == (unsigned long)-1)
		pagesize = 0x1000;

	/* round size up to a page */
	lf->maplen = pagesize * ((lf->len + pagesize - 1) / pagesize);

	/*
	 * XXX hack for dealing with empty files; remove when
	 * we're no longer limited by interfacing to the old
	 * logic elsewhere in this file.
	 */
	if (lf->maplen == 0)
		lf->maplen = pagesize;

	/*
	 * FUTURE: remove PROT_WRITE when the parser no longer
	 * needs to scribble on the input.
	 */
	lf->buf = mmap(NULL, lf->maplen, PROT_READ|PROT_WRITE,
		       MAP_FILE|MAP_COPY, fd, 0);
	if (lf->buf == MAP_FAILED)
		return FALSE;

	if (lf->len == lf->maplen && lf->buf[lf->len - 1] != '\n') {
		char *b = bmake_malloc(lf->len + 1);
		b[lf->len] = '\n';
		memcpy(b, lf->buf, lf->len++);
		munmap(lf->buf, lf->maplen);
		lf->maplen = 0;
		lf->buf = b;
	}

	return TRUE;
}

/*
 * Read in a file.
 *
 * Until the path search logic can be moved under here instead of
 * being in the caller in another source file, we need to have the fd
 * passed in already open. Bleh.
 *
 * If the path is NULL, use stdin.
 */
static struct loadedfile *
loadfile(const char *path, int fd)
{
	struct loadedfile *lf;
	ssize_t result;
	size_t bufpos;

	lf = loadedfile_create(path);

	if (path == NULL) {
		assert(fd == -1);
		fd = STDIN_FILENO;
	} else {
#if 0 /* notyet */
		fd = open(path, O_RDONLY);
		if (fd < 0) {
			...
			Error("%s: %s", path, strerror(errno));
			exit(1);
		}
#endif
	}

	if (loadedfile_mmap(lf, fd))
		goto done;

	/* cannot mmap; load the traditional way */

	lf->maplen = 0;
	lf->len = 1024;
	lf->buf = bmake_malloc(lf->len);

	bufpos = 0;
	for (;;) {
		assert(bufpos <= lf->len);
		if (bufpos == lf->len) {
			if (lf->len > SIZE_MAX/2) {
				errno = EFBIG;
				Error("%s: file too large", path);
				exit(1);
			}
			lf->len *= 2;
			lf->buf = bmake_realloc(lf->buf, lf->len);
		}
		assert(bufpos < lf->len);
		result = read(fd, lf->buf + bufpos, lf->len - bufpos);
		if (result < 0) {
			Error("%s: read error: %s", path, strerror(errno));
			exit(1);
		}
		if (result == 0)
			break;

		bufpos += (size_t)result;
	}
	assert(bufpos <= lf->len);
	lf->len = bufpos;

	/* truncate malloc region to actual length (maybe not useful) */
	if (lf->len > 0) {
		/* as for mmap case, ensure trailing \n */
		if (lf->buf[lf->len - 1] != '\n')
			lf->len++;
		lf->buf = bmake_realloc(lf->buf, lf->len);
		lf->buf[lf->len - 1] = '\n';
	}

done:
	if (path != NULL)
		close(fd);

	return lf;
}

/* old code */

/* Check if the current character is escaped on the current line. */
static Boolean
ParseIsEscaped(const char *line, const char *c)
{
    Boolean active = FALSE;
    for (;;) {
	if (line == c)
	    return active;
	if (*--c != '\\')
	    return active;
	active = !active;
    }
}

/* Add the filename and lineno to the GNode so that we remember where it
 * was first defined. */
static void
ParseMark(GNode *gn)
{
    IFile *curFile = CurFile();
    gn->fname = curFile->fname;
    gn->lineno = curFile->lineno;
}

/* Look in the table of keywords for one matching the given string.
 * Return the index of the keyword, or -1 if it isn't there. */
static int
ParseFindKeyword(const char *str)
{
    int start = 0;
    int end = sizeof parseKeywords / sizeof parseKeywords[0] - 1;

    do {
	int curr = start + (end - start) / 2;
	int diff = strcmp(str, parseKeywords[curr].name);

	if (diff == 0)
	    return curr;
	if (diff < 0)
	    end = curr - 1;
	else
	    start = curr + 1;
    } while (start <= end);

    return -1;
}

static void
PrintLocation(FILE *f, const char *fname, size_t lineno)
{
	char dirbuf[MAXPATHLEN+1];
	const char *dir, *base;
	void *dir_freeIt, *base_freeIt;

	if (*fname == '/' || strcmp(fname, "(stdin)") == 0) {
		(void)fprintf(f, "\"%s\" line %zu: ", fname, lineno);
		return;
	}

	/* Find out which makefile is the culprit.
	 * We try ${.PARSEDIR} and apply realpath(3) if not absolute. */

	dir = Var_Value(".PARSEDIR", VAR_GLOBAL, &dir_freeIt);
	if (dir == NULL)
		dir = ".";
	if (*dir != '/')
		dir = realpath(dir, dirbuf);

	base = Var_Value(".PARSEFILE", VAR_GLOBAL, &base_freeIt);
	if (base == NULL) {
		const char *slash = strrchr(fname, '/');
		base = slash != NULL ? slash + 1 : fname;
	}

	(void)fprintf(f, "\"%s/%s\" line %zu: ", dir, base, lineno);
	bmake_free(base_freeIt);
	bmake_free(dir_freeIt);
}

static void
ParseVErrorInternal(FILE *f, const char *fname, size_t lineno,
		    ParseErrorLevel type, const char *fmt, va_list ap)
{
	static Boolean fatal_warning_error_printed = FALSE;

	(void)fprintf(f, "%s: ", progname);

	if (fname != NULL)
		PrintLocation(f, fname, lineno);
	if (type == PARSE_WARNING)
		(void)fprintf(f, "warning: ");
	(void)vfprintf(f, fmt, ap);
	(void)fprintf(f, "\n");
	(void)fflush(f);

	if (type == PARSE_INFO)
		return;
	if (type == PARSE_FATAL || opts.parseWarnFatal)
		fatals++;
	if (opts.parseWarnFatal && !fatal_warning_error_printed) {
		Error("parsing warnings being treated as errors");
		fatal_warning_error_printed = TRUE;
	}
}

static void
ParseErrorInternal(const char *fname, size_t lineno,
		   ParseErrorLevel type, const char *fmt, ...)
{
	va_list ap;

	(void)fflush(stdout);
	va_start(ap, fmt);
	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
	va_end(ap);

	if (opts.debug_file != stderr && opts.debug_file != stdout) {
		va_start(ap, fmt);
		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
				    fmt, ap);
		va_end(ap);
	}
}

/* Print a parse error message, including location information.
 *
 * If the level is PARSE_FATAL, continue parsing until the end of the
 * current top-level makefile, then exit (see Parse_File).
 *
 * Fmt is given without a trailing newline. */
void
Parse_Error(ParseErrorLevel type, const char *fmt, ...)
{
	va_list ap;
	const char *fname;
	size_t lineno;

	if (includes.len == 0) {
		fname = NULL;
		lineno = 0;
	} else {
		IFile *curFile = CurFile();
		fname = curFile->fname;
		lineno = (size_t)curFile->lineno;
	}

	va_start(ap, fmt);
	(void)fflush(stdout);
	ParseVErrorInternal(stderr, fname, lineno, type, fmt, ap);
	va_end(ap);

	if (opts.debug_file != stderr && opts.debug_file != stdout) {
		va_start(ap, fmt);
		ParseVErrorInternal(opts.debug_file, fname, lineno, type,
				    fmt, ap);
		va_end(ap);
	}
}


/* Parse and handle a .info, .warning or .error directive.
 * For an .error directive, immediately exit. */
static Boolean
ParseMessage(const char *directive)
{
    const char *p = directive;
    ParseErrorLevel mtype = *p == 'i' ? PARSE_INFO :
			    *p == 'w' ? PARSE_WARNING : PARSE_FATAL;
    char *arg;

    while (ch_isalpha(*p))
	p++;
    if (!ch_isspace(*p))
	return FALSE;		/* missing argument */

    cpp_skip_whitespace(&p);
    (void)Var_Subst(p, VAR_CMDLINE, VARE_WANTRES, &arg);
    /* TODO: handle errors */

    Parse_Error(mtype, "%s", arg);
    free(arg);

    if (mtype == PARSE_FATAL) {
	PrintOnError(NULL, NULL);
	exit(1);
    }
    return TRUE;
}

/* Add the child to the parent's children.
 *
 * Additionally, add the parent to the child's parents, but only if the
 * target is not special.  An example for such a special target is .END,
 * which does not need to be informed once the child target has been made. */
static void
LinkSource(GNode *pgn, GNode *cgn, Boolean isSpecial)
{
    if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty(&pgn->cohorts))
	pgn = pgn->cohorts.last->datum;

    Lst_Append(&pgn->children, cgn);
    pgn->unmade++;

    /* Special targets like .END don't need any children. */
    if (!isSpecial)
	Lst_Append(&cgn->parents, pgn);

    if (DEBUG(PARSE)) {
	debug_printf("# %s: added child %s - %s\n",
		     __func__, pgn->name, cgn->name);
	Targ_PrintNode(pgn, 0);
	Targ_PrintNode(cgn, 0);
    }
}

/* Add the node to each target from the current dependency group. */
static void
LinkToTargets(GNode *gn, Boolean isSpecial)
{
    GNodeListNode *ln;
    for (ln = targets->first; ln != NULL; ln = ln->next)
	LinkSource(ln->datum, gn, isSpecial);
}

static Boolean
TryApplyDependencyOperator(GNode *gn, GNodeType op)
{
    /*
     * If the node occurred on the left-hand side of a dependency and the
     * operator also defines a dependency, they must match.
     */
    if ((op & OP_OPMASK) && (gn->type & OP_OPMASK) &&
	((op & OP_OPMASK) != (gn->type & OP_OPMASK)))
    {
	Parse_Error(PARSE_FATAL, "Inconsistent operator for %s", gn->name);
	return FALSE;
    }

    if (op == OP_DOUBLEDEP && (gn->type & OP_OPMASK) == OP_DOUBLEDEP) {
	/*
	 * If the node was of the left-hand side of a '::' operator, we need
	 * to create a new instance of it for the children and commands on
	 * this dependency line since each of these dependency groups has its
	 * own attributes and commands, separate from the others.
	 *
	 * The new instance is placed on the 'cohorts' list of the
	 * initial one (note the initial one is not on its own cohorts list)
	 * and the new instance is linked to all parents of the initial
	 * instance.
	 */
	GNode *cohort;

	/*
	 * Propagate copied bits to the initial node.  They'll be propagated
	 * back to the rest of the cohorts later.
	 */
	gn->type |= op & ~OP_OPMASK;

	cohort = Targ_NewInternalNode(gn->name);
	if (doing_depend)
	    ParseMark(cohort);
	/*
	 * Make the cohort invisible as well to avoid duplicating it into
	 * other variables. True, parents of this target won't tend to do
	 * anything with their local variables, but better safe than
	 * sorry. (I think this is pointless now, since the relevant list
	 * traversals will no longer see this node anyway. -mycroft)
	 */
	cohort->type = op | OP_INVISIBLE;
	Lst_Append(&gn->cohorts, cohort);
	cohort->centurion = gn;
	gn->unmade_cohorts++;
	snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
		 (unsigned int)gn->unmade_cohorts % 1000000);
    } else {
	/*
	 * We don't want to nuke any previous flags (whatever they were) so we
	 * just OR the new operator into the old.
	 */
	gn->type |= op;
    }

    return TRUE;
}

static void
ApplyDependencyOperator(GNodeType op)
{
    GNodeListNode *ln;
    for (ln = targets->first; ln != NULL; ln = ln->next)
	if (!TryApplyDependencyOperator(ln->datum, op))
	    break;
}

static Boolean
ParseDoSrcKeyword(const char *src, ParseSpecial specType)
{
    static int wait_number = 0;
    char wait_src[16];
    GNode *gn;

    if (*src == '.' && ch_isupper(src[1])) {
	int keywd = ParseFindKeyword(src);
	if (keywd != -1) {
	    GNodeType op = parseKeywords[keywd].op;
	    if (op != 0) {
		ApplyDependencyOperator(op);
		return TRUE;
	    }
	    if (parseKeywords[keywd].spec == SP_WAIT) {
		/*
		 * We add a .WAIT node in the dependency list.
		 * After any dynamic dependencies (and filename globbing)
		 * have happened, it is given a dependency on each
		 * previous child, back until the previous .WAIT node.
		 * The next child won't be scheduled until the .WAIT node
		 * is built.
		 * We give each .WAIT node a unique name (mainly for
		 * diagnostics).
		 */
		snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
		gn = Targ_NewInternalNode(wait_src);
		if (doing_depend)
		    ParseMark(gn);
		gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
		LinkToTargets(gn, specType != SP_NOT);
		return TRUE;
	    }
	}
    }
    return FALSE;
}

static void
ParseDoSrcMain(const char *src)
{
    /*
     * In a line like ".MAIN: source1 source2", it means we need to add
     * the sources of said target to the list of things to create.
     *
     * Note that this will only be invoked if the user didn't specify a
     * target on the command line and the .MAIN occurs for the first time.
     *
     * See ParseDoDependencyTargetSpecial, branch SP_MAIN.
     * See unit-tests/cond-func-make-main.mk.
     */
    Lst_Append(&opts.create, bmake_strdup(src));
    /*
     * Add the name to the .TARGETS variable as well, so the user can
     * employ that, if desired.
     */
    Var_Append(".TARGETS", src, VAR_GLOBAL);
}

static void
ParseDoSrcOrder(const char *src)
{
    GNode *gn;
    /*
     * Create proper predecessor/successor links between the previous
     * source and the current one.
     */
    gn = Targ_GetNode(src);
    if (doing_depend)
	ParseMark(gn);
    if (order_pred != NULL) {
	Lst_Append(&order_pred->order_succ, gn);
	Lst_Append(&gn->order_pred, order_pred);
	if (DEBUG(PARSE)) {
	    debug_printf("# %s: added Order dependency %s - %s\n",
			 __func__, order_pred->name, gn->name);
	    Targ_PrintNode(order_pred, 0);
	    Targ_PrintNode(gn, 0);
	}
    }
    /*
     * The current source now becomes the predecessor for the next one.
     */
    order_pred = gn;
}

static void
ParseDoSrcOther(const char *src, GNodeType tOp, ParseSpecial specType)
{
    GNode *gn;

    /*
     * If the source is not an attribute, we need to find/create
     * a node for it. After that we can apply any operator to it
     * from a special target or link it to its parents, as
     * appropriate.
     *
     * In the case of a source that was the object of a :: operator,
     * the attribute is applied to all of its instances (as kept in
     * the 'cohorts' list of the node) or all the cohorts are linked
     * to all the targets.
     */

    /* Find/create the 'src' node and attach to all targets */
    gn = Targ_GetNode(src);
    if (doing_depend)
	ParseMark(gn);
    if (tOp != OP_NONE)
	gn->type |= tOp;
    else
	LinkToTargets(gn, specType != SP_NOT);
}

/* Given the name of a source in a dependency line, figure out if it is an
 * attribute (such as .SILENT) and apply it to the targets if it is. Else
 * decide if there is some attribute which should be applied *to* the source
 * because of some special target (such as .PHONY) and apply it if so.
 * Otherwise, make the source a child of the targets in the list 'targets'.
 *
 * Input:
 *	tOp		operator (if any) from special targets
 *	src		name of the source to handle
 */
static void
ParseDoSrc(GNodeType tOp, const char *src, ParseSpecial specType)
{
    if (ParseDoSrcKeyword(src, specType))
	return;

    if (specType == SP_MAIN)
	ParseDoSrcMain(src);
    else if (specType == SP_ORDER)
	ParseDoSrcOrder(src);
    else
	ParseDoSrcOther(src, tOp, specType);
}

/* If we have yet to decide on a main target to make, in the absence of any
 * user input, we want the first target on the first dependency line that is
 * actually a real target (i.e. isn't a .USE or .EXEC rule) to be made. */
static void
FindMainTarget(void)
{
    GNodeListNode *ln;

    if (mainNode != NULL)
	return;

    for (ln = targets->first; ln != NULL; ln = ln->next) {
	GNode *gn = ln->datum;
	if (!(gn->type & OP_NOTARGET)) {
	    DEBUG1(MAKE, "Setting main node to \"%s\"\n", gn->name);
	    mainNode = gn;
	    Targ_SetMain(gn);
	    return;
	}
    }
}

/*
 * We got to the end of the line while we were still looking at targets.
 *
 * Ending a dependency line without an operator is a Bozo no-no.  As a
 * heuristic, this is also often triggered by undetected conflicts from
 * cvs/rcs merges.
 */
static void
ParseErrorNoDependency(const char *lstart)
{
    if ((strncmp(lstart, "<<<<<<", 6) == 0) ||
	(strncmp(lstart, "======", 6) == 0) ||
	(strncmp(lstart, ">>>>>>", 6) == 0))
	Parse_Error(PARSE_FATAL,
		    "Makefile appears to contain unresolved cvs/rcs/??? merge conflicts");
    else if (lstart[0] == '.') {
	const char *dirstart = lstart + 1;
	const char *dirend;
	cpp_skip_whitespace(&dirstart);
	dirend = dirstart;
	while (ch_isalnum(*dirend) || *dirend == '-')
	    dirend++;
	Parse_Error(PARSE_FATAL, "Unknown directive \"%.*s\"",
		    (int)(dirend - dirstart), dirstart);
    } else
	Parse_Error(PARSE_FATAL, "Need an operator");
}

static void
ParseDependencyTargetWord(const char **pp, const char *lstart)
{
    const char *cp = *pp;

    while (*cp != '\0') {
	if ((ch_isspace(*cp) || *cp == '!' || *cp == ':' || *cp == '(') &&
	    !ParseIsEscaped(lstart, cp))
	    break;

	if (*cp == '$') {
	    /*
	     * Must be a dynamic source (would have been expanded
	     * otherwise), so call the Var module to parse the puppy
	     * so we can safely advance beyond it...There should be
	     * no errors in this, as they would have been discovered
	     * in the initial Var_Subst and we wouldn't be here.
	     */
	    const char *nested_p = cp;
	    const char *nested_val;
	    void *freeIt;

	    (void)Var_Parse(&nested_p, VAR_CMDLINE,
			    VARE_WANTRES | VARE_UNDEFERR, &nested_val, &freeIt);
	    /* TODO: handle errors */
	    free(freeIt);
	    cp += nested_p - cp;
	} else
	    cp++;
    }

    *pp = cp;
}

/* Handle special targets like .PATH, .DEFAULT, .BEGIN, .ORDER. */
static void
ParseDoDependencyTargetSpecial(ParseSpecial *inout_specType,
			       const char *line,
			       SearchPathList **inout_paths)
{
    switch (*inout_specType) {
    case SP_PATH:
	if (*inout_paths == NULL)
	    *inout_paths = Lst_New();
	Lst_Append(*inout_paths, dirSearchPath);
	break;
    case SP_MAIN:
	/* Allow targets from the command line to override the .MAIN node. */
	if (!Lst_IsEmpty(&opts.create))
	    *inout_specType = SP_NOT;
	break;
    case SP_BEGIN:
    case SP_END:
    case SP_STALE:
    case SP_ERROR:
    case SP_INTERRUPT: {
	GNode *gn = Targ_GetNode(line);
	if (doing_depend)
	    ParseMark(gn);
	gn->type |= OP_NOTMAIN|OP_SPECIAL;
	Lst_Append(targets, gn);
	break;
    }
    case SP_DEFAULT: {
	/* Need to create a node to hang commands on, but we don't want it
	 * in the graph, nor do we want it to be the Main Target. We claim
	 * the node is a transformation rule to make life easier later,
	 * when we'll use Make_HandleUse to actually apply the .DEFAULT
	 * commands. */
	GNode *gn = GNode_New(".DEFAULT");
	gn->type |= OP_NOTMAIN|OP_TRANSFORM;
	Lst_Append(targets, gn);
	defaultNode = gn;
	break;
    }
    case SP_DELETE_ON_ERROR:
	deleteOnError = TRUE;
	break;
    case SP_NOTPARALLEL:
	opts.maxJobs = 1;
	break;
    case SP_SINGLESHELL:
	opts.compatMake = TRUE;
	break;
    case SP_ORDER:
	order_pred = NULL;
	break;
    default:
	break;
    }
}

/*
 * .PATH<suffix> has to be handled specially.
 * Call on the suffix module to give us a path to modify.
 */
static Boolean
ParseDoDependencyTargetPath(const char *line, SearchPathList **inout_paths)
{
    SearchPath *path;

    path = Suff_GetPath(&line[5]);
    if (path == NULL) {
	Parse_Error(PARSE_FATAL,
		    "Suffix '%s' not defined (yet)",
		    &line[5]);
	return FALSE;
    }

    if (*inout_paths == NULL)
	*inout_paths = Lst_New();
    Lst_Append(*inout_paths, path);

    return TRUE;
}

/*
 * See if it's a special target and if so set specType to match it.
 */
static Boolean
ParseDoDependencyTarget(const char *line, ParseSpecial *inout_specType,
			GNodeType *out_tOp, SearchPathList **inout_paths)
{
    int keywd;

    if (!(*line == '.' && ch_isupper(line[1])))
	return TRUE;

    /*
     * See if the target is a special target that must have it
     * or its sources handled specially.
     */
    keywd = ParseFindKeyword(line);
    if (keywd != -1) {
	if (*inout_specType == SP_PATH && parseKeywords[keywd].spec != SP_PATH) {
	    Parse_Error(PARSE_FATAL, "Mismatched special targets");
	    return FALSE;
	}

	*inout_specType = parseKeywords[keywd].spec;
	*out_tOp = parseKeywords[keywd].op;

	ParseDoDependencyTargetSpecial(inout_specType, line, inout_paths);

    } else if (strncmp(line, ".PATH", 5) == 0) {
	*inout_specType = SP_PATH;
	if (!ParseDoDependencyTargetPath(line, inout_paths))
	    return FALSE;
    }
    return TRUE;
}

static void
ParseDoDependencyTargetMundane(char *line, StringList *curTargs)
{
    if (Dir_HasWildcards(line)) {
	/*
	 * Targets are to be sought only in the current directory,
	 * so create an empty path for the thing. Note we need to
	 * use Dir_Destroy in the destruction of the path as the
	 * Dir module could have added a directory to the path...
	 */
	SearchPath *emptyPath = SearchPath_New();

	Dir_Expand(line, emptyPath, curTargs);

	SearchPath_Free(emptyPath);
    } else {
	/*
	 * No wildcards, but we want to avoid code duplication,
	 * so create a list with the word on it.
	 */
	Lst_Append(curTargs, line);
    }

    /* Apply the targets. */

    while (!Lst_IsEmpty(curTargs)) {
	char *targName = Lst_Dequeue(curTargs);
	GNode *gn = Suff_IsTransform(targName)
		    ? Suff_AddTransform(targName)
		    : Targ_GetNode(targName);
	if (doing_depend)
	    ParseMark(gn);

	Lst_Append(targets, gn);
    }
}

static void
ParseDoDependencyTargetExtraWarn(char **pp, const char *lstart)
{
    Boolean warning = FALSE;
    char *cp = *pp;

    while (*cp != '\0') {
	if (!ParseIsEscaped(lstart, cp) && (*cp == '!' || *cp == ':'))
	    break;
	if (ParseIsEscaped(lstart, cp) || (*cp != ' ' && *cp != '\t'))
	    warning = TRUE;
	cp++;
    }
    if (warning)
	Parse_Error(PARSE_WARNING, "Extra target ignored");

    *pp = cp;
}

static void
ParseDoDependencyCheckSpec(ParseSpecial specType)
{
    switch (specType) {
    default:
	Parse_Error(PARSE_WARNING,
		    "Special and mundane targets don't mix. "
		    "Mundane ones ignored");
	break;
    case SP_DEFAULT:
    case SP_STALE:
    case SP_BEGIN:
    case SP_END:
    case SP_ERROR:
    case SP_INTERRUPT:
	/*
	 * These create nodes on which to hang commands, so targets
	 * shouldn't be empty...
	 */
    case SP_NOT:
	/* Nothing special here -- targets can be empty if it wants. */
	break;
    }
}

static Boolean
ParseDoDependencyParseOp(char **pp, const char *lstart, GNodeType *out_op)
{
    const char *cp = *pp;

    if (*cp == '!') {
	*out_op = OP_FORCE;
	(*pp)++;
	return TRUE;
    }

    if (*cp == ':') {
	if (cp[1] == ':') {
	    *out_op = OP_DOUBLEDEP;
	    (*pp) += 2;
	} else {
	    *out_op = OP_DEPENDS;
	    (*pp)++;
	}
	return TRUE;
    }

    {
	const char *msg = lstart[0] == '.' ? "Unknown directive"
					   : "Missing dependency operator";
	Parse_Error(PARSE_FATAL, "%s", msg);
	return FALSE;
    }
}

static void
ClearPaths(SearchPathList *paths)
{
    if (paths != NULL) {
	SearchPathListNode *ln;
	for (ln = paths->first; ln != NULL; ln = ln->next)
	    SearchPath_Clear(ln->datum);
    }

    Dir_SetPATH();
}

static void
ParseDoDependencySourcesEmpty(ParseSpecial specType, SearchPathList *paths)
{
    switch (specType) {
    case SP_SUFFIXES:
	Suff_ClearSuffixes();
	break;
    case SP_PRECIOUS:
	allPrecious = TRUE;
	break;
    case SP_IGNORE:
	opts.ignoreErrors = TRUE;
	break;
    case SP_SILENT:
	opts.beSilent = TRUE;
	break;
    case SP_PATH:
	ClearPaths(paths);
	break;
#ifdef POSIX
    case SP_POSIX:
	Var_Set("%POSIX", "1003.2", VAR_GLOBAL);
	break;
#endif
    default:
	break;
    }
}

static void
AddToPaths(const char *dir, SearchPathList *paths)
{
    if (paths != NULL) {
	SearchPathListNode *ln;
	for (ln = paths->first; ln != NULL; ln = ln->next)
	    (void)Dir_AddDir(ln->datum, dir);
    }
}

/*
 * If the target was one that doesn't take files as its sources
 * but takes something like suffixes, we take each
 * space-separated word on the line as a something and deal
 * with it accordingly.
 *
 * If the target was .SUFFIXES, we take each source as a
 * suffix and add it to the list of suffixes maintained by the
 * Suff module.
 *
 * If the target was a .PATH, we add the source as a directory
 * to search on the search path.
 *
 * If it was .INCLUDES, the source is taken to be the suffix of
 * files which will be #included and whose search path should
 * be present in the .INCLUDES variable.
 *
 * If it was .LIBS, the source is taken to be the suffix of
 * files which are considered libraries and whose search path
 * should be present in the .LIBS variable.
 *
 * If it was .NULL, the source is the suffix to use when a file
 * has no valid suffix.
 *
 * If it was .OBJDIR, the source is a new definition for .OBJDIR,
 * and will cause make to do a new chdir to that path.
 */
static void
ParseDoDependencySourceSpecial(ParseSpecial specType, char *word,
			       SearchPathList *paths)
{
    switch (specType) {
    case SP_SUFFIXES:
	Suff_AddSuffix(word, &mainNode);
	break;
    case SP_PATH:
	AddToPaths(word, paths);
	break;
    case SP_INCLUDES:
	Suff_AddInclude(word);
	break;
    case SP_LIBS:
	Suff_AddLib(word);
	break;
    case SP_NULL:
	Suff_SetNull(word);
	break;
    case SP_OBJDIR:
	Main_SetObjdir(FALSE, "%s", word);
	break;
    default:
	break;
    }
}

static Boolean
ParseDoDependencyTargets(char **inout_cp,
			 char **inout_line,
			 const char *lstart,
			 ParseSpecial *inout_specType,
			 GNodeType *inout_tOp,
			 SearchPathList **inout_paths,
			 StringList *curTargs)
{
    char *cp = *inout_cp;
    char *tgt = *inout_line;
    char savec;
    const char *p;

    for (;;) {
	/*
	 * Here LINE points to the beginning of the next word, and
	 * LSTART points to the actual beginning of the line.
	 */

	/* Find the end of the next word. */
	cp = tgt;
	p = cp;
	ParseDependencyTargetWord(&p, lstart);
	cp += p - cp;

	/*
	 * If the word is followed by a left parenthesis, it's the
	 * name of an object file inside an archive (ar file).
	 */
	if (!ParseIsEscaped(lstart, cp) && *cp == '(') {
	    /*
	     * Archives must be handled specially to make sure the OP_ARCHV
	     * flag is set in their 'type' field, for one thing, and because
	     * things like "archive(file1.o file2.o file3.o)" are permissible.
	     * Arch_ParseArchive will set 'line' to be the first non-blank
	     * after the archive-spec. It creates/finds nodes for the members
	     * and places them on the given list, returning TRUE if all
	     * went well and FALSE if there was an error in the
	     * specification. On error, line should remain untouched.
	     */
	    if (!Arch_ParseArchive(&tgt, targets, VAR_CMDLINE)) {
		Parse_Error(PARSE_FATAL,
			    "Error in archive specification: \"%s\"",
			    tgt);
		return FALSE;
	    }

	    cp = tgt;
	    continue;
	}

	if (*cp == '\0') {
	    ParseErrorNoDependency(lstart);
	    return FALSE;
	}

	/* Insert a null terminator. */
	savec = *cp;
	*cp = '\0';

	if (!ParseDoDependencyTarget(tgt, inout_specType, inout_tOp,
				     inout_paths))
	    return FALSE;

	/*
	 * Have word in line. Get or create its node and stick it at
	 * the end of the targets list
	 */
	if (*inout_specType == SP_NOT && *tgt != '\0')
	    ParseDoDependencyTargetMundane(tgt, curTargs);
	else if (*inout_specType == SP_PATH && *tgt != '.' && *tgt != '\0')
	    Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", tgt);

	/* Don't need the inserted null terminator any more. */
	*cp = savec;

	/*
	 * If it is a special type and not .PATH, it's the only target we
	 * allow on this line...
	 */
	if (*inout_specType != SP_NOT && *inout_specType != SP_PATH)
	    ParseDoDependencyTargetExtraWarn(&cp, lstart);
	else
	    pp_skip_whitespace(&cp);

	tgt = cp;
	if (*tgt == '\0')
	    break;
	if ((*tgt == '!' || *tgt == ':') && !ParseIsEscaped(lstart, tgt))
	    break;
    }

    *inout_cp = cp;
    *inout_line = tgt;
    return TRUE;
}

static void
ParseDoDependencySourcesSpecial(char *start, char *end,
				ParseSpecial specType, SearchPathList *paths)
{
    char savec;

    while (*start != '\0') {
	while (*end != '\0' && !ch_isspace(*end))
	    end++;
	savec = *end;
	*end = '\0';
	ParseDoDependencySourceSpecial(specType, start, paths);
	*end = savec;
	if (savec != '\0')
	    end++;
	pp_skip_whitespace(&end);
	start = end;
    }
}

static Boolean
ParseDoDependencySourcesMundane(char *start, char *end,
				ParseSpecial specType, GNodeType tOp)
{
    while (*start != '\0') {
	/*
	 * The targets take real sources, so we must beware of archive
	 * specifications (i.e. things with left parentheses in them)
	 * and handle them accordingly.
	 */
	for (; *end != '\0' && !ch_isspace(*end); end++) {
	    if (*end == '(' && end > start && end[-1] != '$') {
		/*
		 * Only stop for a left parenthesis if it isn't at the
		 * start of a word (that'll be for variable changes
		 * later) and isn't preceded by a dollar sign (a dynamic
		 * source).
		 */
		break;
	    }
	}

	if (*end == '(') {
	    GNodeList *sources = Lst_New();
	    if (!Arch_ParseArchive(&start, sources, VAR_CMDLINE)) {
		Parse_Error(PARSE_FATAL,
			    "Error in source archive spec \"%s\"", start);
		return FALSE;
	    }

	    while (!Lst_IsEmpty(sources)) {
		GNode *gn = Lst_Dequeue(sources);
		ParseDoSrc(tOp, gn->name, specType);
	    }
	    Lst_Free(sources);
	    end = start;
	} else {
	    if (*end != '\0') {
		*end = '\0';
		end++;
	    }

	    ParseDoSrc(tOp, start, specType);
	}
	pp_skip_whitespace(&end);
	start = end;
    }
    return TRUE;
}

/* Parse a dependency line consisting of targets, followed by a dependency
 * operator, optionally followed by sources.
 *
 * The nodes of the sources are linked as children to the nodes of the
 * targets. Nodes are created as necessary.
 *
 * The operator is applied to each node in the global 'targets' list,
 * which is where the nodes found for the targets are kept, by means of
 * the ParseDoOp function.
 *
 * The sources are parsed in much the same way as the targets, except
 * that they are expanded using the wildcarding scheme of the C-Shell,
 * and a target is created for each expanded word. Each of the resulting
 * nodes is then linked to each of the targets as one of its children.
 *
 * Certain targets and sources such as .PHONY or .PRECIOUS are handled
 * specially. These are the ones detailed by the specType variable.
 *
 * The storing of transformation rules such as '.c.o' is also taken care of
 * here. A target is recognized as a transformation rule by calling
 * Suff_IsTransform. If it is a transformation rule, its node is gotten
 * from the suffix module via Suff_AddTransform rather than the standard
 * Targ_FindNode in the target module.
 *
 * Upon return, the value of the line is unspecified.
 */
static void
ParseDoDependency(char *line)
{
    char *cp;			/* our current position */
    GNodeType op;		/* the operator on the line */
    SearchPathList *paths;	/* search paths to alter when parsing
				 * a list of .PATH targets */
    GNodeType tOp;		/* operator from special target */
    StringList *curTargs;	/* target names to be found and added
				 * to the targets list */
    char *lstart = line;

    /*
     * specType contains the SPECial TYPE of the current target. It is SP_NOT
     * if the target is unspecial. If it *is* special, however, the children
     * are linked as children of the parent but not vice versa.
     */
    ParseSpecial specType = SP_NOT;

    DEBUG1(PARSE, "ParseDoDependency(%s)\n", line);
    tOp = OP_NONE;

    paths = NULL;

    curTargs = Lst_New();

    /*
     * First, grind through the targets.
     */
    if (!ParseDoDependencyTargets(&cp, &line, lstart, &specType, &tOp, &paths,
				  curTargs))
	goto out;

    /* Don't need the list of target names anymore.
     * The targets themselves are now in the global variable 'targets'. */
    Lst_Free(curTargs);
    curTargs = NULL;

    if (!Lst_IsEmpty(targets))
	ParseDoDependencyCheckSpec(specType);

    /*
     * Have now parsed all the target names. Must parse the operator next.
     */
    if (!ParseDoDependencyParseOp(&cp, lstart, &op))
	goto out;

    /*
     * Apply the operator to the target. This is how we remember which
     * operator a target was defined with. It fails if the operator
     * used isn't consistent across all references.
     */
    ApplyDependencyOperator(op);

    /*
     * Onward to the sources.
     *
     * LINE will now point to the first source word, if any, or the
     * end of the string if not.
     */
    pp_skip_whitespace(&cp);
    line = cp;			/* XXX: 'line' is an inappropriate name */

    /*
     * Several special targets take different actions if present with no
     * sources:
     *	a .SUFFIXES line with no sources clears out all old suffixes
     *	a .PRECIOUS line makes all targets precious
     *	a .IGNORE line ignores errors for all targets
     *	a .SILENT line creates silence when making all targets
     *	a .PATH removes all directories from the search path(s).
     */
    if (line[0] == '\0') {
	ParseDoDependencySourcesEmpty(specType, paths);
    } else if (specType == SP_MFLAGS) {
	/*
	 * Call on functions in main.c to deal with these arguments and
	 * set the initial character to a null-character so the loop to
	 * get sources won't get anything
	 */
	Main_ParseArgLine(line);
	*line = '\0';
    } else if (specType == SP_SHELL) {
	if (!Job_ParseShell(line)) {
	    Parse_Error(PARSE_FATAL, "improper shell specification");
	    goto out;
	}
	*line = '\0';
    } else if (specType == SP_NOTPARALLEL || specType == SP_SINGLESHELL ||
	       specType == SP_DELETE_ON_ERROR) {
	*line = '\0';
    }

    /* Now go for the sources. */
    if (specType == SP_SUFFIXES || specType == SP_PATH ||
	specType == SP_INCLUDES || specType == SP_LIBS ||
	specType == SP_NULL || specType == SP_OBJDIR)
    {
	ParseDoDependencySourcesSpecial(line, cp, specType, paths);
	if (paths != NULL) {
	    Lst_Free(paths);
	    paths = NULL;
	}
	if (specType == SP_PATH)
	    Dir_SetPATH();
    } else {
	assert(paths == NULL);
	if (!ParseDoDependencySourcesMundane(line, cp, specType, tOp))
	    goto out;
    }

    FindMainTarget();

out:
    if (paths != NULL)
	Lst_Free(paths);
    if (curTargs != NULL)
	Lst_Free(curTargs);
}

typedef struct VarAssignParsed {
    const char *nameStart;	/* unexpanded */
    const char *nameEnd;	/* before operator adjustment */
    const char *eq;		/* the '=' of the assignment operator */
} VarAssignParsed;

/* Determine the assignment operator and adjust the end of the variable
 * name accordingly. */
static void
AdjustVarassignOp(const VarAssignParsed *pvar, const char *value,
		  VarAssign *out_var)
{
    const char *op = pvar->eq;
    const char * const name = pvar->nameStart;
    VarAssignOp type;

    if (op > name && op[-1] == '+') {
	type = VAR_APPEND;
	op--;

    } else if (op > name && op[-1] == '?') {
	op--;
	type = VAR_DEFAULT;

    } else if (op > name && op[-1] == ':') {
	op--;
	type = VAR_SUBST;

    } else if (op > name && op[-1] == '!') {
	op--;
	type = VAR_SHELL;

    } else {
	type = VAR_NORMAL;
#ifdef SUNSHCMD
	while (op > name && ch_isspace(op[-1]))
	    op--;

	if (op >= name + 3 && op[-3] == ':' && op[-2] == 's' && op[-1] == 'h') {
	    type = VAR_SHELL;
	    op -= 3;
	}
#endif
    }

    {
	const char *nameEnd = pvar->nameEnd < op ? pvar->nameEnd : op;
	out_var->varname = bmake_strsedup(pvar->nameStart, nameEnd);
	out_var->op = type;
	out_var->value = value;
    }
}

/* Parse a variable assignment, consisting of a single-word variable name,
 * optional whitespace, an assignment operator, optional whitespace and the
 * variable value.
 *
 * Note: There is a lexical ambiguity with assignment modifier characters
 * in variable names. This routine interprets the character before the =
 * as a modifier. Therefore, an assignment like
 *	C++=/usr/bin/CC
 * is interpreted as "C+ +=" instead of "C++ =".
 *
 * Used for both lines in a file and command line arguments. */
Boolean
Parse_IsVar(const char *p, VarAssign *out_var)
{
    VarAssignParsed pvar;
    const char *firstSpace = NULL;
    int level = 0;

    cpp_skip_hspace(&p);	/* Skip to variable name */

    /* During parsing, the '+' of the '+=' operator is initially parsed
     * as part of the variable name.  It is later corrected, as is the ':sh'
     * modifier. Of these two (nameEnd and op), the earlier one determines the
     * actual end of the variable name. */
    pvar.nameStart = p;
#ifdef CLEANUP
    pvar.nameEnd = NULL;
    pvar.eq = NULL;
#endif

    /* Scan for one of the assignment operators outside a variable expansion */
    while (*p != '\0') {
	char ch = *p++;
	if (ch == '(' || ch == '{') {
	    level++;
	    continue;
	}
	if (ch == ')' || ch == '}') {
	    level--;
	    continue;
	}

	if (level != 0)
	    continue;

	if (ch == ' ' || ch == '\t')
	    if (firstSpace == NULL)
		firstSpace = p - 1;
	while (ch == ' ' || ch == '\t')
	    ch = *p++;

#ifdef SUNSHCMD
	if (ch == ':' && p[0] == 's' && p[1] == 'h') {
	    p += 2;
	    continue;
	}
#endif
	if (ch == '=') {
	    pvar.eq = p - 1;
	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p - 1;
	    cpp_skip_whitespace(&p);
	    AdjustVarassignOp(&pvar, p, out_var);
	    return TRUE;
	}
	if (*p == '=' && (ch == '+' || ch == ':' || ch == '?' || ch == '!')) {
	    pvar.eq = p;
	    pvar.nameEnd = firstSpace != NULL ? firstSpace : p;
	    p++;
	    cpp_skip_whitespace(&p);
	    AdjustVarassignOp(&pvar, p, out_var);
	    return TRUE;
	}
	if (firstSpace != NULL)
	    return FALSE;
    }

    return FALSE;
}

static void
VarCheckSyntax(VarAssignOp type, const char *uvalue, GNode *ctxt)
{
    if (opts.lint) {
	if (type != VAR_SUBST && strchr(uvalue, '$') != NULL) {
	    /* Check for syntax errors such as unclosed expressions or
	     * unknown modifiers. */
	    char *expandedValue;

	    (void)Var_Subst(uvalue, ctxt, VARE_NONE, &expandedValue);
	    /* TODO: handle errors */
	    free(expandedValue);
	}
    }
}

static void
VarAssign_EvalSubst(const char *name, const char *uvalue, GNode *ctxt,
		    const char **out_avalue, void **out_avalue_freeIt)
{
    const char *avalue = uvalue;
    char *evalue;
    Boolean savedPreserveUndefined = preserveUndefined;

    /* TODO: Can this assignment to preserveUndefined be moved further down
     * to the actually interesting Var_Subst call, without affecting any
     * edge cases?
     *
     * It might affect the implicit expansion of the variable name in the
     * Var_Exists and Var_Set calls, even though it's unlikely that anyone
     * cared about this edge case when adding this code.  In addition,
     * variable assignments should not refer to any undefined variables in
     * the variable name. */
    preserveUndefined = TRUE;

    /*
     * make sure that we set the variable the first time to nothing
     * so that it gets substituted!
     */
    if (!Var_Exists(name, ctxt))
	Var_Set(name, "", ctxt);

    (void)Var_Subst(uvalue, ctxt, VARE_WANTRES|VARE_KEEP_DOLLAR, &evalue);
    /* TODO: handle errors */
    preserveUndefined = savedPreserveUndefined;
    avalue = evalue;
    Var_Set(name, avalue, ctxt);

    *out_avalue = avalue;
    *out_avalue_freeIt = evalue;
}

static void
VarAssign_EvalShell(const char *name, const char *uvalue, GNode *ctxt,
		    const char **out_avalue, void **out_avalue_freeIt)
{
    const char *cmd, *errfmt;
    char *cmdOut;
    void *cmd_freeIt = NULL;

    cmd = uvalue;
    if (strchr(cmd, '$') != NULL) {
	char *ecmd;
	(void)Var_Subst(cmd, VAR_CMDLINE, VARE_WANTRES | VARE_UNDEFERR, &ecmd);
	/* TODO: handle errors */
	cmd = cmd_freeIt = ecmd;
    }

    cmdOut = Cmd_Exec(cmd, &errfmt);
    Var_Set(name, cmdOut, ctxt);
    *out_avalue = *out_avalue_freeIt = cmdOut;

    if (errfmt != NULL)
	Parse_Error(PARSE_WARNING, errfmt, cmd);

    free(cmd_freeIt);
}

/* Perform a variable assignment.
 *
 * The actual value of the variable is returned in *out_avalue and
 * *out_avalue_freeIt.  Especially for VAR_SUBST and VAR_SHELL this can differ
 * from the literal value.
 *
 * Return whether the assignment was actually done.  The assignment is only
 * skipped if the operator is '?=' and the variable already exists. */
static Boolean
VarAssign_Eval(const char *name, VarAssignOp op, const char *uvalue,
	       GNode *ctxt, const char **out_avalue, void **out_avalue_freeIt)
{
    const char *avalue = uvalue;
    void *avalue_freeIt = NULL;

    if (op == VAR_APPEND)
	Var_Append(name, uvalue, ctxt);
    else if (op == VAR_SUBST)
	VarAssign_EvalSubst(name, uvalue, ctxt, &avalue, &avalue_freeIt);
    else if (op == VAR_SHELL)
	VarAssign_EvalShell(name, uvalue, ctxt, &avalue, &avalue_freeIt);
    else {
	if (op == VAR_DEFAULT && Var_Exists(name, ctxt)) {
	    *out_avalue_freeIt = NULL;
	    return FALSE;
	}

	/* Normal assignment -- just do it. */
	Var_Set(name, uvalue, ctxt);
    }

    *out_avalue = avalue;
    *out_avalue_freeIt = avalue_freeIt;
    return TRUE;
}

static void
VarAssignSpecial(const char *name, const char *avalue)
{
    if (strcmp(name, MAKEOVERRIDES) == 0)
	Main_ExportMAKEFLAGS(FALSE);	/* re-export MAKEFLAGS */
    else if (strcmp(name, ".CURDIR") == 0) {
	/*
	 * Someone is being (too?) clever...
	 * Let's pretend they know what they are doing and
	 * re-initialize the 'cur' CachedDir.
	 */
	Dir_InitCur(avalue);
	Dir_SetPATH();
    } else if (strcmp(name, MAKE_JOB_PREFIX) == 0)
	Job_SetPrefix();
    else if (strcmp(name, MAKE_EXPORTED) == 0)
	Var_Export(avalue, FALSE);
}

/* Perform the variable variable assignment in the given context. */
void
Parse_DoVar(VarAssign *var, GNode *ctxt)
{
    const char *avalue;		/* actual value (maybe expanded) */
    void *avalue_freeIt;

    VarCheckSyntax(var->op, var->value, ctxt);
    if (VarAssign_Eval(var->varname, var->op, var->value, ctxt,
		       &avalue, &avalue_freeIt))
	VarAssignSpecial(var->varname, avalue);

    free(avalue_freeIt);
    free(var->varname);
}


/* See if the command possibly calls a sub-make by using the variable
 * expressions ${.MAKE}, ${MAKE} or the plain word "make". */
static Boolean
MaybeSubMake(const char *cmd)
{
    const char *start;

    for (start = cmd; *start != '\0'; start++) {
	const char *p = start;
	char endc;

	/* XXX: What if progname != "make"? */
	if (p[0] == 'm' && p[1] == 'a' && p[2] == 'k' && p[3] == 'e')
	    if (start == cmd || !ch_isalnum(p[-1]))
		if (!ch_isalnum(p[4]))
		    return TRUE;

	if (*p != '$')
	    continue;
	p++;

	if (*p == '{')
	    endc = '}';
	else if (*p == '(')
	    endc = ')';
	else
	    continue;
	p++;

	if (*p == '.')		/* Accept either ${.MAKE} or ${MAKE}. */
	    p++;

	if (p[0] == 'M' && p[1] == 'A' && p[2] == 'K' && p[3] == 'E')
	    if (p[4] == endc)
		return TRUE;
    }
    return FALSE;
}

/* Append the command to the target node.
 *
 * The node may be marked as a submake node if the command is determined to
 * be that. */
static void
ParseAddCmd(GNode *gn, char *cmd)
{
    /* Add to last (ie current) cohort for :: targets */
    if ((gn->type & OP_DOUBLEDEP) && gn->cohorts.last != NULL)
	gn = gn->cohorts.last->datum;

    /* if target already supplied, ignore commands */
    if (!(gn->type & OP_HAS_COMMANDS)) {
	Lst_Append(&gn->commands, cmd);
	if (MaybeSubMake(cmd))
	    gn->type |= OP_SUBMAKE;
	ParseMark(gn);
    } else {
#if 0
	/* XXX: We cannot do this until we fix the tree */
	Lst_Append(gn->commands, cmd);
	Parse_Error(PARSE_WARNING,
		     "overriding commands for target \"%s\"; "
		     "previous commands defined at %s: %d ignored",
		     gn->name, gn->fname, gn->lineno);
#else
	Parse_Error(PARSE_WARNING,
		    "duplicate script for target \"%s\" ignored",
		    gn->name);
	ParseErrorInternal(gn->fname, (size_t)gn->lineno, PARSE_WARNING,
			   "using previous script for \"%s\" defined here",
			   gn->name);
#endif
    }
}

/* Add a directory to the path searched for included makefiles bracketed
 * by double-quotes. */
void
Parse_AddIncludeDir(const char *dir)
{
    (void)Dir_AddDir(parseIncPath, dir);
}

/* Handle one of the .[-ds]include directives by remembering the current file
 * and pushing the included file on the stack.  After the included file has
 * finished, parsing continues with the including file; see Parse_SetInput
 * and ParseEOF.
 *
 * System includes are looked up in sysIncPath, any other includes are looked
 * up in the parsedir and then in the directories specified by the -I command
 * line options.
 */
static void
Parse_include_file(char *file, Boolean isSystem, Boolean depinc, Boolean silent)
{
    struct loadedfile *lf;
    char *fullname;		/* full pathname of file */
    char *newName;
    char *slash, *incdir;
    int fd;
    int i;

    fullname = file[0] == '/' ? bmake_strdup(file) : NULL;

    if (fullname == NULL && !isSystem) {
	/*
	 * Include files contained in double-quotes are first searched
	 * relative to the including file's location. We don't want to
	 * cd there, of course, so we just tack on the old file's
	 * leading path components and call Dir_FindFile to see if
	 * we can locate the file.
	 */

	incdir = bmake_strdup(CurFile()->fname);
	slash = strrchr(incdir, '/');
	if (slash != NULL) {
	    *slash = '\0';
	    /* Now do lexical processing of leading "../" on the filename */
	    for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
		slash = strrchr(incdir + 1, '/');
		if (slash == NULL || strcmp(slash, "/..") == 0)
		    break;
		*slash = '\0';
	    }
	    newName = str_concat3(incdir, "/", file + i);
	    fullname = Dir_FindFile(newName, parseIncPath);
	    if (fullname == NULL)
		fullname = Dir_FindFile(newName, dirSearchPath);
	    free(newName);
	}
	free(incdir);

	if (fullname == NULL) {
	    /*
	     * Makefile wasn't found in same directory as included makefile.
	     * Search for it first on the -I search path,
	     * then on the .PATH search path, if not found in a -I directory.
	     * If we have a suffix specific path we should use that.
	     */
	    const char *suff;
	    SearchPath *suffPath = NULL;

	    if ((suff = strrchr(file, '.'))) {
		suffPath = Suff_GetPath(suff);
		if (suffPath != NULL)
		    fullname = Dir_FindFile(file, suffPath);
	    }
	    if (fullname == NULL) {
		fullname = Dir_FindFile(file, parseIncPath);
		if (fullname == NULL)
		    fullname = Dir_FindFile(file, dirSearchPath);
	    }
	}
    }

    /* Looking for a system file or file still not found */
    if (fullname == NULL) {
	/*
	 * Look for it on the system path
	 */
	SearchPath *path = Lst_IsEmpty(sysIncPath) ? defSysIncPath : sysIncPath;
	fullname = Dir_FindFile(file, path);
    }

    if (fullname == NULL) {
	if (!silent)
	    Parse_Error(PARSE_FATAL, "Could not find %s", file);
	return;
    }

    /* Actually open the file... */
    fd = open(fullname, O_RDONLY);
    if (fd == -1) {
	if (!silent)
	    Parse_Error(PARSE_FATAL, "Cannot open %s", fullname);
	free(fullname);
	return;
    }

    /* load it */
    lf = loadfile(fullname, fd);

    /* Start reading from this file next */
    Parse_SetInput(fullname, 0, -1, loadedfile_nextbuf, lf);
    CurFile()->lf = lf;
    if (depinc)
	doing_depend = depinc;	/* only turn it on */
}

static void
ParseDoInclude(char *line)
{
    char endc;			/* the character which ends the file spec */
    char *cp;			/* current position in file spec */
    Boolean silent = *line != 'i';
    char *file = line + (silent ? 8 : 7);

    /* Skip to delimiter character so we know where to look */
    pp_skip_hspace(&file);

    if (*file != '"' && *file != '<') {
	Parse_Error(PARSE_FATAL,
		    ".include filename must be delimited by '\"' or '<'");
	return;
    }

    /*
     * Set the search path on which to find the include file based on the
     * characters which bracket its name. Angle-brackets imply it's
     * a system Makefile while double-quotes imply it's a user makefile
     */
    if (*file == '<')
	endc = '>';
    else
	endc = '"';

    /* Skip to matching delimiter */
    for (cp = ++file; *cp && *cp != endc; cp++)
	continue;

    if (*cp != endc) {
	Parse_Error(PARSE_FATAL,
		    "Unclosed .include filename. '%c' expected", endc);
	return;
    }

    *cp = '\0';

    /*
     * Substitute for any variables in the filename before trying to
     * find the file.
     */
    (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &file);
    /* TODO: handle errors */

    Parse_include_file(file, endc == '>', *line == 'd', silent);
    free(file);
}

/* Split filename into dirname + basename, then assign these to the
 * given variables. */
static void
SetFilenameVars(const char *filename, const char *dirvar, const char *filevar)
{
    const char *slash, *dirname, *basename;
    void *freeIt;

    slash = strrchr(filename, '/');
    if (slash == NULL) {
	dirname = curdir;
	basename = filename;
	freeIt = NULL;
    } else {
	dirname = freeIt = bmake_strsedup(filename, slash);
	basename = slash + 1;
    }

    Var_Set(dirvar, dirname, VAR_GLOBAL);
    Var_Set(filevar, basename, VAR_GLOBAL);

    DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
	   __func__, dirvar, dirname, filevar, basename);
    free(freeIt);
}

/* Return the immediately including file.
 *
 * This is made complicated since the .for loop is implemented as a special
 * kind of .include; see For_Run. */
static const char *
GetActuallyIncludingFile(void)
{
    size_t i;
    const IFile *incs = GetInclude(0);

    for (i = includes.len; i >= 2; i--)
	if (!incs[i - 1].fromForLoop)
	    return incs[i - 2].fname;
    return NULL;
}

/* Set .PARSEDIR, .PARSEFILE, .INCLUDEDFROMDIR and .INCLUDEDFROMFILE. */
static void
ParseSetParseFile(const char *filename)
{
    const char *including;

    SetFilenameVars(filename, ".PARSEDIR", ".PARSEFILE");

    including = GetActuallyIncludingFile();
    if (including != NULL) {
	SetFilenameVars(including,
			".INCLUDEDFROMDIR", ".INCLUDEDFROMFILE");
    } else {
	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
    }
}

static Boolean
StrContainsWord(const char *str, const char *word)
{
    size_t strLen = strlen(str);
    size_t wordLen = strlen(word);
    const char *p, *end;

    if (strLen < wordLen)
	return FALSE;		/* str is too short to contain word */

    end = str + strLen - wordLen;
    for (p = str; p != NULL; p = strchr(p, ' ')) {
	if (*p == ' ')
	    p++;
	if (p > end)
	    return FALSE;	/* cannot contain word */

	if (memcmp(p, word, wordLen) == 0 &&
	    (p[wordLen] == '\0' || p[wordLen] == ' '))
	    return TRUE;
    }
    return FALSE;
}

/* XXX: Searching through a set of words with this linear search is
 * inefficient for variables that contain thousands of words. */
/* XXX: The paths in this list don't seem to be normalized in any way. */
static Boolean
VarContainsWord(const char *varname, const char *word)
{
    void *val_freeIt;
    const char *val = Var_Value(varname, VAR_GLOBAL, &val_freeIt);
    Boolean found = val != NULL && StrContainsWord(val, word);
    bmake_free(val_freeIt);
    return found;
}

/* Track the makefiles we read - so makefiles can set dependencies on them.
 * Avoid adding anything more than once.
 *
 * Time complexity: O(n) per call, in total O(n^2), where n is the number
 * of makefiles that have been loaded. */
static void
ParseTrackInput(const char *name)
{
    if (!VarContainsWord(MAKE_MAKEFILES, name))
	Var_Append(MAKE_MAKEFILES, name, VAR_GLOBAL);
}


/* Start parsing from the given source.
 *
 * The given file is added to the includes stack. */
void
Parse_SetInput(const char *name, int line, int fd,
	       char *(*nextbuf)(void *, size_t *), void *arg)
{
    IFile *curFile;
    char *buf;
    size_t len;
    Boolean fromForLoop = name == NULL;

    if (fromForLoop)
	name = CurFile()->fname;
    else
	ParseTrackInput(name);

    if (DEBUG(PARSE))
	debug_printf("%s: file %s, line %d, fd %d, nextbuf %s, arg %p\n",
		     __func__, name, line, fd,
		     nextbuf == loadedfile_nextbuf ? "loadedfile" : "other",
		     arg);

    if (fd == -1 && nextbuf == NULL)
	/* sanity */
	return;

    curFile = Vector_Push(&includes);
    curFile->fname = bmake_strdup(name);
    curFile->fromForLoop = fromForLoop;
    curFile->lineno = line;
    curFile->first_lineno = line;
    curFile->nextbuf = nextbuf;
    curFile->nextbuf_arg = arg;
    curFile->lf = NULL;
    curFile->depending = doing_depend;	/* restore this on EOF */

    assert(nextbuf != NULL);

    /* Get first block of input data */
    buf = curFile->nextbuf(curFile->nextbuf_arg, &len);
    if (buf == NULL) {
	/* Was all a waste of time ... */
	if (curFile->fname)
	    free(curFile->fname);
	free(curFile);
	return;
    }
    curFile->buf_freeIt = buf;
    curFile->buf_ptr = buf;
    curFile->buf_end = buf + len;

    curFile->cond_depth = Cond_save_depth();
    ParseSetParseFile(name);
}

/* Check if the directive is an include directive. */
static Boolean
IsInclude(const char *dir, Boolean sysv)
{
	if (dir[0] == 's' || dir[0] == '-' || (dir[0] == 'd' && !sysv))
		dir++;

	if (strncmp(dir, "include", 7) != 0)
		return FALSE;

	/* Space is not mandatory for BSD .include */
	return !sysv || ch_isspace(dir[7]);
}


#ifdef SYSVINCLUDE
/* Check if the line is a SYSV include directive. */
static Boolean
IsSysVInclude(const char *line)
{
	const char *p;

	if (!IsInclude(line, TRUE))
		return FALSE;

	/* Avoid interpreting a dependency line as an include */
	for (p = line; (p = strchr(p, ':')) != NULL;) {

		/* end of line -> it's a dependency */
		if (*++p == '\0')
			return FALSE;

		/* '::' operator or ': ' -> it's a dependency */
		if (*p == ':' || ch_isspace(*p))
			return FALSE;
	}
	return TRUE;
}

/* Push to another file.  The line points to the word "include". */
static void
ParseTraditionalInclude(char *line)
{
    char *cp;			/* current position in file spec */
    Boolean done = FALSE;
    Boolean silent = line[0] != 'i';
    char *file = line + (silent ? 8 : 7);
    char *all_files;

    DEBUG2(PARSE, "%s: %s\n", __func__, file);

    pp_skip_whitespace(&file);

    /*
     * Substitute for any variables in the file name before trying to
     * find the thing.
     */
    (void)Var_Subst(file, VAR_CMDLINE, VARE_WANTRES, &all_files);
    /* TODO: handle errors */

    if (*file == '\0') {
	Parse_Error(PARSE_FATAL, "Filename missing from \"include\"");
	goto out;
    }

    for (file = all_files; !done; file = cp + 1) {
	/* Skip to end of line or next whitespace */
	for (cp = file; *cp != '\0' && !ch_isspace(*cp); cp++)
	    continue;

	if (*cp != '\0')
	    *cp = '\0';
	else
	    done = TRUE;

	Parse_include_file(file, FALSE, FALSE, silent);
    }
out:
    free(all_files);
}
#endif

#ifdef GMAKEEXPORT
/* Parse "export <variable>=<value>", and actually export it. */
static void
ParseGmakeExport(char *line)
{
    char *variable = line + 6;
    char *value;

    DEBUG2(PARSE, "%s: %s\n", __func__, variable);

    pp_skip_whitespace(&variable);

    for (value = variable; *value && *value != '='; value++)
	continue;

    if (*value != '=') {
	Parse_Error(PARSE_FATAL,
		    "Variable/Value missing from \"export\"");
	return;
    }
    *value++ = '\0';		/* terminate variable */

    /*
     * Expand the value before putting it in the environment.
     */
    (void)Var_Subst(value, VAR_CMDLINE, VARE_WANTRES, &value);
    /* TODO: handle errors */

    setenv(variable, value, 1);
    free(value);
}
#endif

/* Called when EOF is reached in the current file. If we were reading an
 * include file or a .for loop, the includes stack is popped and things set
 * up to go back to reading the previous file at the previous location.
 *
 * Results:
 *	TRUE to continue parsing, i.e. it had only reached the end of an
 *	included file, FALSE if the main file has been parsed completely.
 */
static Boolean
ParseEOF(void)
{
    char *ptr;
    size_t len;
    IFile *curFile = CurFile();

    assert(curFile->nextbuf != NULL);

    doing_depend = curFile->depending;	/* restore this */
    /* get next input buffer, if any */
    ptr = curFile->nextbuf(curFile->nextbuf_arg, &len);
    curFile->buf_ptr = ptr;
    curFile->buf_freeIt = ptr;
    curFile->buf_end = ptr + len; /* XXX: undefined behavior if ptr == NULL */
    curFile->lineno = curFile->first_lineno;
    if (ptr != NULL)
	return TRUE;		/* Iterate again */

    /* Ensure the makefile (or loop) didn't have mismatched conditionals */
    Cond_restore_depth(curFile->cond_depth);

    if (curFile->lf != NULL) {
	loadedfile_destroy(curFile->lf);
	curFile->lf = NULL;
    }

    /* Dispose of curFile info */
    /* Leak curFile->fname because all the gnodes have pointers to it */
    free(curFile->buf_freeIt);
    Vector_Pop(&includes);

    if (includes.len == 0) {
	/* We've run out of input */
	Var_Delete(".PARSEDIR", VAR_GLOBAL);
	Var_Delete(".PARSEFILE", VAR_GLOBAL);
	Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
	Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
	return FALSE;
    }

    curFile = CurFile();
    DEBUG2(PARSE, "ParseEOF: returning to file %s, line %d\n",
	   curFile->fname, curFile->lineno);

    ParseSetParseFile(curFile->fname);
    return TRUE;
}

typedef enum GetLineMode {
    PARSE_NORMAL,
    PARSE_RAW,
    PARSE_SKIP
} GetLineMode;

static char *
ParseGetLine(GetLineMode mode)
{
    IFile *cf = CurFile();
    char *ptr;
    char ch;
    char *line;
    char *line_end;
    char *escaped;
    char *comment;
    char *tp;

    /* Loop through blank lines and comment lines */
    for (;;) {
	cf->lineno++;
	line = cf->buf_ptr;
	ptr = line;
	line_end = line;
	escaped = NULL;
	comment = NULL;
	for (;;) {
	    /* XXX: can buf_end ever be null? */
	    if (cf->buf_end != NULL && ptr == cf->buf_end) {
		/* end of buffer */
		ch = '\0';
		break;
	    }
	    ch = *ptr;
	    if (ch == '\0' || (ch == '\\' && ptr[1] == '\0')) {
		/* XXX: can buf_end ever be null? */
		if (cf->buf_end == NULL)
		    /* End of string (aka for loop) data */
		    break;
		/* see if there is more we can parse */
		while (ptr++ < cf->buf_end) {
		    if ((ch = *ptr) == '\n') {
			if (ptr > line && ptr[-1] == '\\')
			    continue;
			Parse_Error(PARSE_WARNING,
				    "Zero byte read from file, "
				    "skipping rest of line.");
			break;
		    }
		}
		/* XXX: Can cf->nextbuf ever be NULL? */
		if (cf->nextbuf != NULL) {
		    /*
		     * End of this buffer; return EOF and outer logic
		     * will get the next one. (eww)
		     */
		    break;
		}
		Parse_Error(PARSE_FATAL, "Zero byte read from file");
		return NULL;
	    }

	    if (ch == '\\') {
		/* Don't treat next character as special, remember first one */
		if (escaped == NULL)
		    escaped = ptr;
		if (ptr[1] == '\n')
		    cf->lineno++;
		ptr += 2;
		line_end = ptr;
		continue;
	    }
	    if (ch == '#' && comment == NULL) {
		/* Remember first '#' for comment stripping */
		/* Unless previous char was '[', as in modifier :[#] */
		if (!(ptr > line && ptr[-1] == '['))
		    comment = line_end;
	    }
	    ptr++;
	    if (ch == '\n')
		break;
	    if (!ch_isspace(ch))
		/* We are not interested in trailing whitespace */
		line_end = ptr;
	}

	/* Save next 'to be processed' location */
	cf->buf_ptr = ptr;

	/* Check we have a non-comment, non-blank line */
	if (line_end == line || comment == line) {
	    if (ch == '\0')
		/* At end of file */
		return NULL;
	    /* Parse another line */
	    continue;
	}

	/* We now have a line of data */
	*line_end = '\0';

	if (mode == PARSE_RAW) {
	    /* Leave '\' (etc) in line buffer (eg 'for' lines) */
	    return line;
	}

	if (mode == PARSE_SKIP) {
	    /* Completely ignore non-directives */
	    if (line[0] != '.')
		continue;
	    /* We could do more of the .else/.elif/.endif checks here */
	}
	break;
    }

    /* Brutally ignore anything after a non-escaped '#' in non-commands */
    if (comment != NULL && line[0] != '\t') {
	line_end = comment;
	*line_end = '\0';
    }

    /* If we didn't see a '\\' then the in-situ data is fine */
    if (escaped == NULL)
	return line;

    /* Remove escapes from '\n' and '#' */
    tp = ptr = escaped;
    escaped = line;
    for (; ; *tp++ = ch) {
	ch = *ptr++;
	if (ch != '\\') {
	    if (ch == '\0')
		break;
	    continue;
	}

	ch = *ptr++;
	if (ch == '\0') {
	    /* Delete '\\' at end of buffer */
	    tp--;
	    break;
	}

	if (ch == '#' && line[0] != '\t')
	    /* Delete '\\' from before '#' on non-command lines */
	    continue;

	if (ch != '\n') {
	    /* Leave '\\' in buffer for later */
	    *tp++ = '\\';
	    /* Make sure we don't delete an escaped ' ' from the line end */
	    escaped = tp + 1;
	    continue;
	}

	/* Escaped '\n' -- replace following whitespace with a single ' '. */
	pp_skip_hspace(&ptr);
	ch = ' ';
    }

    /* Delete any trailing spaces - eg from empty continuations */
    while (tp > escaped && ch_isspace(tp[-1]))
	tp--;

    *tp = '\0';
    return line;
}

/* Read an entire line from the input file. Called only by Parse_File.
 *
 * Results:
 *	A line without its newline and without any trailing whitespace.
 */
static char *
ParseReadLine(void)
{
    char *line;			/* Result */
    int lineno;			/* Saved line # */
    int rval;

    for (;;) {
	line = ParseGetLine(PARSE_NORMAL);
	if (line == NULL)
	    return NULL;

	if (line[0] != '.')
	    return line;

	/*
	 * The line might be a conditional. Ask the conditional module
	 * about it and act accordingly
	 */
	switch (Cond_EvalLine(line)) {
	case COND_SKIP:
	    /* Skip to next conditional that evaluates to COND_PARSE.  */
	    do {
		line = ParseGetLine(PARSE_SKIP);
	    } while (line && Cond_EvalLine(line) != COND_PARSE);
	    if (line == NULL)
		break;
	    continue;
	case COND_PARSE:
	    continue;
	case COND_INVALID:	/* Not a conditional line */
	    /* Check for .for loops */
	    rval = For_Eval(line);
	    if (rval == 0)
		/* Not a .for line */
		break;
	    if (rval < 0)
		/* Syntax error - error printed, ignore line */
		continue;
	    /* Start of a .for loop */
	    lineno = CurFile()->lineno;
	    /* Accumulate loop lines until matching .endfor */
	    do {
		line = ParseGetLine(PARSE_RAW);
		if (line == NULL) {
		    Parse_Error(PARSE_FATAL,
				"Unexpected end of file in for loop.");
		    break;
		}
	    } while (For_Accum(line));
	    /* Stash each iteration as a new 'input file' */
	    For_Run(lineno);
	    /* Read next line from for-loop buffer */
	    continue;
	}
	return line;
    }
}

static void
FinishDependencyGroup(void)
{
    GNodeListNode *ln;

    if (targets == NULL)
	return;

    for (ln = targets->first; ln != NULL; ln = ln->next) {
	GNode *gn = ln->datum;

	Suff_EndTransform(gn);

	/* Mark the target as already having commands if it does, to
	 * keep from having shell commands on multiple dependency lines. */
	if (!Lst_IsEmpty(&gn->commands))
	    gn->type |= OP_HAS_COMMANDS;
    }

    Lst_Free(targets);
    targets = NULL;
}

/* Add the command to each target from the current dependency spec. */
static void
ParseLine_ShellCommand(const char *p)
{
    cpp_skip_whitespace(&p);
    if (*p == '\0')
	return;			/* skip empty commands */

    if (targets == NULL) {
	Parse_Error(PARSE_FATAL, "Unassociated shell command \"%s\"", p);
	return;
    }

    {
	char *cmd = bmake_strdup(p);
	GNodeListNode *ln;

	for (ln = targets->first; ln != NULL; ln = ln->next) {
	    GNode *gn = ln->datum;
	    ParseAddCmd(gn, cmd);
	}
#ifdef CLEANUP
	Lst_Append(&targCmds, cmd);
#endif
    }
}

static Boolean
ParseDirective(char *line)
{
    char *cp;

    if (*line == '.') {
	/*
	 * Lines that begin with '.' can be pretty much anything:
	 *	- directives like '.include' or '.if',
	 *	- suffix rules like '.c.o:',
	 *	- dependencies for filenames that start with '.',
	 *	- variable assignments like '.tmp=value'.
	 */
	cp = line + 1;
	pp_skip_whitespace(&cp);
	if (IsInclude(cp, FALSE)) {
	    ParseDoInclude(cp);
	    return TRUE;
	}
	if (strncmp(cp, "undef", 5) == 0) {
	    const char *varname;
	    cp += 5;
	    pp_skip_whitespace(&cp);
	    varname = cp;
	    for (; !ch_isspace(*cp) && *cp != '\0'; cp++)
		continue;
	    *cp = '\0';
	    Var_Delete(varname, VAR_GLOBAL);
	    /* TODO: undefine all variables, not only the first */
	    /* TODO: use Str_Words, like everywhere else */
	    return TRUE;
	} else if (strncmp(cp, "export", 6) == 0) {
	    cp += 6;
	    pp_skip_whitespace(&cp);
	    Var_Export(cp, TRUE);
	    return TRUE;
	} else if (strncmp(cp, "unexport", 8) == 0) {
	    Var_UnExport(cp);
	    return TRUE;
	} else if (strncmp(cp, "info", 4) == 0 ||
		   strncmp(cp, "error", 5) == 0 ||
		   strncmp(cp, "warning", 7) == 0) {
	    if (ParseMessage(cp))
		return TRUE;
	}
    }
    return FALSE;
}

static Boolean
ParseVarassign(const char *line)
{
    VarAssign var;

    if (!Parse_IsVar(line, &var))
	return FALSE;

    FinishDependencyGroup();
    Parse_DoVar(&var, VAR_GLOBAL);
    return TRUE;
}

static char *
FindSemicolon(char *p)
{
    int level = 0;

    for (; *p != '\0'; p++) {
	if (*p == '\\' && p[1] != '\0') {
	    p++;
	    continue;
	}

	if (*p == '$' && (p[1] == '(' || p[1] == '{'))
	    level++;
	else if (level > 0 && (*p == ')' || *p == '}'))
	    level--;
	else if (level == 0 && *p == ';')
	    break;
    }
    return p;
}

/* dependency	-> target... op [source...]
 * op		-> ':' | '::' | '!' */
static void
ParseDependency(char *line)
{
    VarEvalFlags eflags;
    char *expanded_line;
    const char *shellcmd = NULL;

    /*
     * For some reason - probably to make the parser impossible -
     * a ';' can be used to separate commands from dependencies.
     * Attempt to avoid ';' inside substitution patterns.
     */
    {
	char *semicolon = FindSemicolon(line);
	if (*semicolon != '\0') {
	    /* Terminate the dependency list at the ';' */
	    *semicolon = '\0';
	    shellcmd = semicolon + 1;
	}
    }

    /*
     * We now know it's a dependency line so it needs to have all
     * variables expanded before being parsed.
     *
     * XXX: Ideally the dependency line would first be split into
     * its left-hand side, dependency operator and right-hand side,
     * and then each side would be expanded on its own.  This would
     * allow for the left-hand side to allow only defined variables
     * and to allow variables on the right-hand side to be undefined
     * as well.
     *
     * Parsing the line first would also prevent that targets
     * generated from variable expressions are interpreted as the
     * dependency operator, such as in "target${:U\:} middle: source",
     * in which the middle is interpreted as a source, not a target.
     */

    /* In lint mode, allow undefined variables to appear in
     * dependency lines.
     *
     * Ideally, only the right-hand side would allow undefined
     * variables since it is common to have optional dependencies.
     * Having undefined variables on the left-hand side is more
     * unusual though.  Since both sides are expanded in a single
     * pass, there is not much choice what to do here.
     *
     * In normal mode, it does not matter whether undefined
     * variables are allowed or not since as of 2020-09-14,
     * Var_Parse does not print any parse errors in such a case.
     * It simply returns the special empty string var_Error,
     * which cannot be detected in the result of Var_Subst. */
    eflags = opts.lint ? VARE_WANTRES : VARE_WANTRES | VARE_UNDEFERR;
    (void)Var_Subst(line, VAR_CMDLINE, eflags, &expanded_line);
    /* TODO: handle errors */

    /* Need a fresh list for the target nodes */
    if (targets != NULL)
	Lst_Free(targets);
    targets = Lst_New();

    ParseDoDependency(expanded_line);
    free(expanded_line);

    if (shellcmd != NULL)
	ParseLine_ShellCommand(shellcmd);
}

static void
ParseLine(char *line)
{
    if (ParseDirective(line))
	return;

    if (*line == '\t') {
	ParseLine_ShellCommand(line + 1);
	return;
    }

#ifdef SYSVINCLUDE
    if (IsSysVInclude(line)) {
	/*
	 * It's an S3/S5-style "include".
	 */
	ParseTraditionalInclude(line);
	return;
    }
#endif

#ifdef GMAKEEXPORT
    if (strncmp(line, "export", 6) == 0 && ch_isspace(line[6]) &&
	strchr(line, ':') == NULL) {
	/*
	 * It's a Gmake "export".
	 */
	ParseGmakeExport(line);
	return;
    }
#endif

    if (ParseVarassign(line))
	return;

    FinishDependencyGroup();

    ParseDependency(line);
}

/* Parse a top-level makefile, incorporating its content into the global
 * dependency graph.
 *
 * Input:
 *	name		The name of the file being read
 *	fd		The open file to parse; will be closed at the end
 */
void
Parse_File(const char *name, int fd)
{
    char *line;			/* the line we're working on */
    struct loadedfile *lf;

    lf = loadfile(name, fd);

    assert(targets == NULL);

    if (name == NULL)
	name = "(stdin)";

    Parse_SetInput(name, 0, -1, loadedfile_nextbuf, lf);
    CurFile()->lf = lf;

    do {
	while ((line = ParseReadLine()) != NULL) {
	    DEBUG2(PARSE, "ParseReadLine (%d): '%s'\n",
		   CurFile()->lineno, line);
	    ParseLine(line);
	}
	/*
	 * Reached EOF, but it may be just EOF of an include file...
	 */
    } while (ParseEOF());

    FinishDependencyGroup();

    if (fatals != 0) {
	(void)fflush(stdout);
	(void)fprintf(stderr,
		      "%s: Fatal errors encountered -- cannot continue",
		      progname);
	PrintOnError(NULL, NULL);
	exit(1);
    }
}

/* Initialize the parsing module. */
void
Parse_Init(void)
{
    mainNode = NULL;
    parseIncPath = SearchPath_New();
    sysIncPath = SearchPath_New();
    defSysIncPath = SearchPath_New();
    Vector_Init(&includes, sizeof(IFile));
}

/* Clean up the parsing module. */
void
Parse_End(void)
{
#ifdef CLEANUP
    Lst_DoneCall(&targCmds, free);
    assert(targets == NULL);
    SearchPath_Free(defSysIncPath);
    SearchPath_Free(sysIncPath);
    SearchPath_Free(parseIncPath);
    assert(includes.len == 0);
    Vector_Done(&includes);
#endif
}


/*
 * Return a list containing the single main target to create.
 * If no such target exists, we Punt with an obnoxious error message.
 */
void
Parse_MainName(GNodeList *mainList)
{
    if (mainNode == NULL)
	Punt("no target to make.");

    if (mainNode->type & OP_DOUBLEDEP) {
	Lst_Append(mainList, mainNode);
	Lst_AppendAll(mainList, &mainNode->cohorts);
    } else
	Lst_Append(mainList, mainNode);

    Var_Append(".TARGETS", mainNode->name, VAR_GLOBAL);
}

int
Parse_GetFatals(void)
{
    return fatals;
}