Merge branch 'vendor/WPA_SUPPLICANT'

[dragonfly.git] / contrib / bmake / parse.c

/*      $NetBSD: parse.c,v 1.550 2021/02/22 23:21:33 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 IncludeFile instead.
 *
 *      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/stat.h>
#include <errno.h>
#include <stdarg.h>

#include "make.h"

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#ifdef HAVE_MMAP
#include <sys/mman.h>

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

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

/*      "@(#)parse.c    8.3 (Berkeley) 3/19/94" */
MAKE_RCSID("$NetBSD: parse.c,v 1.550 2021/02/22 23:21:33 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;

        /* Function to read more data, with a single opaque argument. */
        ReadMoreProc readMore;
        void *readMoreArg;

        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 */
        /* .MAIN and we don't have anything user-specified to make */
        SP_MAIN,
        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 index 0 is the top-level makefile from
 * the command line, followed by the included files or .for loops, up to and
 * including the current file.
 *
 * See PrintStackTrace for how to interpret the data.
 */
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;       /* directories for "..." includes */
SearchPath *sysIncPath;         /* directories 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,       OP_NONE },
    { ".DEFAULT",       SP_DEFAULT,     OP_NONE },
    { ".DELETE_ON_ERROR", SP_DELETE_ON_ERROR, OP_NONE },
    { ".END",           SP_END,         OP_NONE },
    { ".ERROR",         SP_ERROR,       OP_NONE },
    { ".EXEC",          SP_ATTRIBUTE,   OP_EXEC },
    { ".IGNORE",        SP_IGNORE,      OP_IGNORE },
    { ".INCLUDES",      SP_INCLUDES,    OP_NONE },
    { ".INTERRUPT",     SP_INTERRUPT,   OP_NONE },
    { ".INVISIBLE",     SP_ATTRIBUTE,   OP_INVISIBLE },
    { ".JOIN",          SP_ATTRIBUTE,   OP_JOIN },
    { ".LIBS",          SP_LIBS,        OP_NONE },
    { ".MADE",          SP_ATTRIBUTE,   OP_MADE },
    { ".MAIN",          SP_MAIN,        OP_NONE },
    { ".MAKE",          SP_ATTRIBUTE,   OP_MAKE },
    { ".MAKEFLAGS",     SP_MFLAGS,      OP_NONE },
    { ".META",          SP_META,        OP_META },
    { ".MFLAGS",        SP_MFLAGS,      OP_NONE },
    { ".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, OP_NONE },
    { ".NO_PARALLEL",   SP_NOTPARALLEL, OP_NONE },
    { ".NULL",          SP_NULL,        OP_NONE },
    { ".OBJDIR",        SP_OBJDIR,      OP_NONE },
    { ".OPTIONAL",      SP_ATTRIBUTE,   OP_OPTIONAL },
    { ".ORDER",         SP_ORDER,       OP_NONE },
    { ".PARALLEL",      SP_PARALLEL,    OP_NONE },
    { ".PATH",          SP_PATH,        OP_NONE },
    { ".PHONY",         SP_PHONY,       OP_PHONY },
#ifdef POSIX
    { ".POSIX",         SP_POSIX,       OP_NONE },
#endif
    { ".PRECIOUS",      SP_PRECIOUS,    OP_PRECIOUS },
    { ".RECURSIVE",     SP_ATTRIBUTE,   OP_MAKE },
    { ".SHELL",         SP_SHELL,       OP_NONE },
    { ".SILENT",        SP_SILENT,      OP_SILENT },
    { ".SINGLESHELL",   SP_SINGLESHELL, OP_NONE },
    { ".STALE",         SP_STALE,       OP_NONE },
    { ".SUFFIXES",      SP_SUFFIXES,    OP_NONE },
    { ".USE",           SP_ATTRIBUTE,   OP_USE },
    { ".USEBEFORE",     SP_ATTRIBUTE,   OP_USEBEFORE },
    { ".WAIT",          SP_WAIT,        OP_NONE },
};

/* 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 */
        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, char *buf, size_t buflen)
{
        struct loadedfile *lf;

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

static void
loadedfile_destroy(struct loadedfile *lf)
{
        free(lf->buf);
        free(lf);
}

/*
 * readMore() 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_readMore(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 1 GiB. 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 > 0x3fffffff)
                return FALSE;

        *ret = (size_t)st.st_size;
        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)
{
        ssize_t n;
        Buffer buf;
        size_t filesize;


        if (path == NULL) {
                assert(fd == -1);
                fd = STDIN_FILENO;
        }

        if (load_getsize(fd, &filesize)) {
                /*
                 * Avoid resizing the buffer later for no reason.
                 *
                 * At the same time leave space for adding a final '\n',
                 * just in case it is missing in the file.
                 */
                filesize++;
        } else
                filesize = 1024;
        Buf_InitSize(&buf, filesize);

        for (;;) {
                assert(buf.len <= buf.cap);
                if (buf.len == buf.cap) {
                        if (buf.cap > 0x1fffffff) {
                                errno = EFBIG;
                                Error("%s: file too large", path);
                                exit(2); /* Not 1 so -q can distinguish error */
                        }
                        Buf_Expand(&buf);
                }
                assert(buf.len < buf.cap);
                n = read(fd, buf.data + buf.len, buf.cap - buf.len);
                if (n < 0) {
                        Error("%s: read error: %s", path, strerror(errno));
                        exit(2);        /* Not 1 so -q can distinguish error */
                }
                if (n == 0)
                        break;

                buf.len += (size_t)n;
        }
        assert(buf.len <= buf.cap);

        if (!Buf_EndsWith(&buf, '\n'))
                Buf_AddByte(&buf, '\n');

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

        {
                struct loadedfile *lf = loadedfile_create(path,
                    buf.data, buf.len);
                Buf_DoneData(&buf);
                return lf;
        }
}

static void
PrintStackTrace(void)
{
        const IFile *entries;
        size_t i, n;

        if (!(DEBUG(PARSE)))
                return;

        entries = GetInclude(0);
        n = includes.len;
        if (n == 0)
                return;
        n--;                    /* This entry is already in the diagnostic. */

        /*
         * For the IFiles with fromForLoop, lineno seems to be sorted
         * backwards.  This is because lineno is the number of completely
         * parsed lines, which for a .for loop is right after the
         * corresponding .endfor.  The intuitive line number comes from
         * first_lineno instead, which points at the start of the .for loop.
         *
         * To make the stack trace intuitive, the entry below each chain of
         * .for loop entries must be ignored completely since neither its
         * lineno nor its first_lineno is useful.  Instead, the topmost of
         * each chain of .for loop entries needs to be printed twice, once
         * with its first_lineno and once with its lineno.
         */

        for (i = n; i-- > 0;) {
                const IFile *entry = entries + i;
                const char *fname = entry->fname;
                Boolean printLineno;
                char dirbuf[MAXPATHLEN + 1];

                if (fname[0] != '/' && strcmp(fname, "(stdin)") != 0)
                        fname = realpath(fname, dirbuf);

                printLineno = !entry->fromForLoop;
                if (i + 1 < n && entries[i + 1].fromForLoop == printLineno)
                        printLineno = entry->fromForLoop;

                if (printLineno)
                        debug_printf("\tin .include from %s:%d\n",
                            fname, entry->lineno);
                if (entry->fromForLoop)
                        debug_printf("\tin .for loop from %s:%d\n",
                            fname, entry->first_lineno);
        }
}

/* 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];
        FStr dir, base;

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

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

        dir = Var_Value(SCOPE_GLOBAL, ".PARSEDIR");
        if (dir.str == NULL)
                dir.str = ".";
        if (dir.str[0] != '/')
                dir.str = realpath(dir.str, dirbuf);

        base = Var_Value(SCOPE_GLOBAL, ".PARSEFILE");
        if (base.str == NULL)
                base.str = str_basename(fname);

        (void)fprintf(f, "\"%s/%s\" line %u: ",
            dir.str, base.str, (unsigned)lineno);

        FStr_Done(&base);
        FStr_Done(&dir);
}

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)
                goto print_stack_trace;
        if (type == PARSE_WARNING && !opts.parseWarnFatal)
                goto print_stack_trace;
        fatals++;
        if (type == PARSE_WARNING && !fatal_warning_error_printed) {
                Error("parsing warnings being treated as errors");
                fatal_warning_error_printed = TRUE;
        }

print_stack_trace:
        PrintStackTrace();
}

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 an .info, .warning or .error directive.
 * For an .error directive, immediately exit.
 */
static void
ParseMessage(ParseErrorLevel level, const char *levelName, const char *umsg)
{
        char *xmsg;

        if (umsg[0] == '\0') {
                Parse_Error(PARSE_FATAL, "Missing argument for \".%s\"",
                    levelName);
                return;
        }

        (void)Var_Subst(umsg, SCOPE_CMDLINE, VARE_WANTRES, &xmsg);
        /* TODO: handle errors */

        Parse_Error(level, "%s", xmsg);
        free(xmsg);

        if (level == PARSE_FATAL) {
                PrintOnError(NULL, NULL);
                exit(1);
        }
}

/*
 * 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;
}

/*
 * 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).
 */
static void
ParseDependencySourceWait(Boolean isSpecial)
{
        static int wait_number = 0;
        char wait_src[16];
        GNode *gn;

        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, isSpecial);

}

static Boolean
ParseDependencySourceKeyword(const char *src, ParseSpecial specType)
{
        int keywd;
        GNodeType op;

        if (*src != '.' || !ch_isupper(src[1]))
                return FALSE;

        keywd = ParseFindKeyword(src);
        if (keywd == -1)
                return FALSE;

        op = parseKeywords[keywd].op;
        if (op != OP_NONE) {
                ApplyDependencyOperator(op);
                return TRUE;
        }
        if (parseKeywords[keywd].spec == SP_WAIT) {
                ParseDependencySourceWait(specType != SP_NOT);
                return TRUE;
        }
        return FALSE;
}

static void
ParseDependencySourceMain(const char *src)
{
        /*
         * In a line like ".MAIN: source1 source2", add all sources to the
         * list of things to create, but only if the user didn't specify a
         * target on the command line and .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.
         */
        Global_Append(".TARGETS", src);
}

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

        /*
         * The source is not an attribute, so find/create a node for it.
         * After that, 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
ParseDependencySource(GNodeType tOp, const char *src, ParseSpecial specType)
{
        if (ParseDependencySourceKeyword(src, specType))
                return;

        if (specType == SP_MAIN)
                ParseDependencySourceMain(src);
        else if (specType == SP_ORDER)
                ParseDependencySourceOrder(src);
        else
                ParseDependencySourceOther(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, "Invalid line type");
}

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;
                        FStr nested_val;

                        (void)Var_Parse(&nested_p, SCOPE_CMDLINE, VARE_NONE,
                            &nested_val);
                        /* TODO: handle errors */
                        FStr_Done(&nested_val);
                        cp += nested_p - cp;
                } else
                        cp++;
        }

        *pp = cp;
}

/* Handle special targets like .PATH, .DEFAULT, .BEGIN, .ORDER. */
static void
ParseDoDependencyTargetSpecial(ParseSpecial *inout_specType,
                               const char *targetName,
                               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(targetName);
                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 *suffixName,
                            SearchPathList **inout_paths)
{
        SearchPath *path;

        path = Suff_GetPath(suffixName);
        if (path == NULL) {
                Parse_Error(PARSE_FATAL,
                    "Suffix '%s' not defined (yet)", suffixName);
                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 *targetName,
                        ParseSpecial *inout_specType,
                        GNodeType *out_tOp, SearchPathList **inout_paths)
{
        int keywd;

        if (!(targetName[0] == '.' && ch_isupper(targetName[1])))
                return TRUE;

        /*
         * See if the target is a special target that must have it
         * or its sources handled specially.
         */
        keywd = ParseFindKeyword(targetName);
        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, targetName,
                    inout_paths);

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

static void
ParseDoDependencyTargetMundane(char *targetName, StringList *curTargs)
{
        if (Dir_HasWildcards(targetName)) {
                /*
                 * 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();

                SearchPath_Expand(emptyPath, targetName, 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, targetName);
        }

        /* 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:
                Global_Set("%POSIX", "1003.2");
                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)SearchPath_Add(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;
        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, SCOPE_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_INIT;
                        if (!Arch_ParseArchive(&start, &sources,
                            SCOPE_CMDLINE)) {
                                Parse_Error(PARSE_FATAL,
                                    "Error in source archive spec \"%s\"",
                                    start);
                                return FALSE;
                        }

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

                        ParseDependencySource(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 */
        /* target names to be found and added to the targets list */
        StringList curTargs = LST_INIT;
        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;

        /*
         * First, grind through the targets.
         */
        /* XXX: don't use line as an iterator variable */
        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_Done(&curTargs);
        Lst_Init(&curTargs);

        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);
        Lst_Done(&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;
}

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

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

static void
VarAssign_EvalSubst(GNode *scope, const char *name, const char *uvalue,
                    FStr *out_avalue)
{
        char *evalue;

        /*
         * make sure that we set the variable the first time to nothing
         * so that it gets substituted.
         *
         * TODO: Add a test that demonstrates why this code is needed,
         *  apart from making the debug log longer.
         */
        if (!Var_ExistsExpand(scope, name))
                Var_SetExpand(scope, name, "");

        (void)Var_Subst(uvalue, scope,
            VARE_WANTRES | VARE_KEEP_DOLLAR | VARE_KEEP_UNDEF, &evalue);
        /* TODO: handle errors */

        Var_SetExpand(scope, name, evalue);

        *out_avalue = FStr_InitOwn(evalue);
}

static void
VarAssign_EvalShell(const char *name, const char *uvalue, GNode *scope,
                    FStr *out_avalue)
{
        FStr cmd;
        const char *errfmt;
        char *cmdOut;

        cmd = FStr_InitRefer(uvalue);
        if (strchr(cmd.str, '$') != NULL) {
                char *expanded;
                (void)Var_Subst(cmd.str, SCOPE_CMDLINE,
                    VARE_WANTRES | VARE_UNDEFERR, &expanded);
                /* TODO: handle errors */
                cmd = FStr_InitOwn(expanded);
        }

        cmdOut = Cmd_Exec(cmd.str, &errfmt);
        Var_SetExpand(scope, name, cmdOut);
        *out_avalue = FStr_InitOwn(cmdOut);

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

        FStr_Done(&cmd);
}

/*
 * Perform a variable assignment.
 *
 * The actual value of the variable is returned in *out_TRUE_avalue.
 * Especially for VAR_SUBST and VAR_SHELL this can differ from the literal
 * value.
 *
 * Return whether the assignment was actually performed, which is usually
 * the case.  It 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 *scope, FStr *out_TRUE_avalue)
{
        FStr avalue = FStr_InitRefer(uvalue);

        if (op == VAR_APPEND)
                Var_AppendExpand(scope, name, uvalue);
        else if (op == VAR_SUBST)
                VarAssign_EvalSubst(scope, name, uvalue, &avalue);
        else if (op == VAR_SHELL)
                VarAssign_EvalShell(name, uvalue, scope, &avalue);
        else {
                if (op == VAR_DEFAULT && Var_ExistsExpand(scope, name))
                        return FALSE;

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

        *out_TRUE_avalue = avalue;
        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_ExportVars(avalue);
}

/* Perform the variable variable assignment in the given scope. */
void
Parse_DoVar(VarAssign *var, GNode *scope)
{
        FStr avalue;    /* actual value (maybe expanded) */

        VarCheckSyntax(var->op, var->value, scope);
        if (VarAssign_Eval(var->varname, var->op, var->value, scope, &avalue)) {
                VarAssignSpecial(var->varname, avalue.str);
                FStr_Done(&avalue);
        }

        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)SearchPath_Add(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
IncludeFile(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, '.')) != NULL) {
                                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->dirs)
                    ? 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_readMore, lf);
        CurFile()->lf = lf;
        if (depinc)
                doing_depend = depinc;  /* only turn it on */
}

static void
ParseDoInclude(char *directive)
{
        char endc;              /* the character which ends the file spec */
        char *cp;               /* current position in file spec */
        Boolean silent = directive[0] != 'i';
        char *file = directive + (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 != '\0' && *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, SCOPE_CMDLINE, VARE_WANTRES, &file);
        /* TODO: handle errors */

        IncludeFile(file, endc == '>', directive[0] == '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, *basename;
        FStr dirname;

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

        Global_SetExpand(dirvar, dirname.str);
        Global_SetExpand(filevar, basename);

        DEBUG5(PARSE, "%s: ${%s} = `%s' ${%s} = `%s'\n",
            __func__, dirvar, dirname.str, filevar, basename);
        FStr_Done(&dirname);
}

/*
 * 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 {
                Global_Delete(".INCLUDEDFROMDIR");
                Global_Delete(".INCLUDEDFROMFILE");
        }
}

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)
{
        FStr val = Var_Value(SCOPE_GLOBAL, varname);
        Boolean found = val.str != NULL && StrContainsWord(val.str, word);
        FStr_Done(&val);
        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))
                Global_Append(MAKE_MAKEFILES, name);
}


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

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

        DEBUG3(PARSE, "Parse_SetInput: %s %s, line %d\n",
            readMore == loadedfile_readMore ? "file" : ".for loop in",
            name, lineno);

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

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

        assert(readMore != NULL);

        /* Get first block of input data */
        buf = curFile->readMore(curFile->readMoreArg, &len);
        if (buf == NULL) {
                /* Was all a waste of time ... */
                if (curFile->fname != NULL)
                        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, SCOPE_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;

                IncludeFile(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 != '\0' && *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, SCOPE_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->readMore != NULL);

        doing_depend = curFile->depending;      /* restore this */
        /* get next input buffer, if any */
        ptr = curFile->readMore(curFile->readMoreArg, &len);
        curFile->buf_ptr = ptr;
        curFile->buf_freeIt = ptr;
        curFile->buf_end = ptr == NULL ? NULL : ptr + len;
        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 */
                Global_Delete(".PARSEDIR");
                Global_Delete(".PARSEFILE");
                Global_Delete(".INCLUDEDFROMDIR");
                Global_Delete(".INCLUDEDFROMFILE");
                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 ParseRawLineResult {
        PRLR_LINE,
        PRLR_EOF,
        PRLR_ERROR
} ParseRawLineResult;

/*
 * Parse until the end of a line, taking into account lines that end with
 * backslash-newline.
 */
static ParseRawLineResult
ParseRawLine(IFile *curFile, char **out_line, char **out_line_end,
             char **out_firstBackslash, char **out_firstComment)
{
        char *line = curFile->buf_ptr;
        char *p = line;
        char *line_end = line;
        char *firstBackslash = NULL;
        char *firstComment = NULL;
        ParseRawLineResult res = PRLR_LINE;

        curFile->lineno++;

        for (;;) {
                char ch;

                if (p == curFile->buf_end) {
                        res = PRLR_EOF;
                        break;
                }

                ch = *p;
                if (ch == '\0' ||
                    (ch == '\\' && p + 1 < curFile->buf_end && p[1] == '\0')) {
                        Parse_Error(PARSE_FATAL, "Zero byte read from file");
                        return PRLR_ERROR;
                }

                /* Treat next character after '\' as literal. */
                if (ch == '\\') {
                        if (firstBackslash == NULL)
                                firstBackslash = p;
                        if (p[1] == '\n') {
                                curFile->lineno++;
                                if (p + 2 == curFile->buf_end) {
                                        line_end = p;
                                        *line_end = '\n';
                                        p += 2;
                                        continue;
                                }
                        }
                        p += 2;
                        line_end = p;
                        assert(p <= curFile->buf_end);
                        continue;
                }

                /*
                 * Remember the first '#' for comment stripping, unless
                 * the previous char was '[', as in the modifier ':[#]'.
                 */
                if (ch == '#' && firstComment == NULL &&
                    !(p > line && p[-1] == '['))
                        firstComment = line_end;

                p++;
                if (ch == '\n')
                        break;

                /* We are not interested in trailing whitespace. */
                if (!ch_isspace(ch))
                        line_end = p;
        }

        *out_line = line;
        curFile->buf_ptr = p;
        *out_line_end = line_end;
        *out_firstBackslash = firstBackslash;
        *out_firstComment = firstComment;
        return res;
}

/*
 * Beginning at start, unescape '\#' to '#' and replace backslash-newline
 * with a single space.
 */
static void
UnescapeBackslash(char *line, char *start)
{
        char *src = start;
        char *dst = start;
        char *spaceStart = line;

        for (;;) {
                char ch = *src++;
                if (ch != '\\') {
                        if (ch == '\0')
                                break;
                        *dst++ = ch;
                        continue;
                }

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

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

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

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

        /* Delete any trailing spaces - eg from empty continuations */
        while (dst > spaceStart && ch_isspace(dst[-1]))
                dst--;
        *dst = '\0';
}

typedef enum GetLineMode {
        /*
         * Return the next line that is neither empty nor a comment.
         * Backslash line continuations are folded into a single space.
         * A trailing comment, if any, is discarded.
         */
        GLM_NONEMPTY,

        /*
         * Return the next line, even if it is empty or a comment.
         * Preserve backslash-newline to keep the line numbers correct.
         *
         * Used in .for loops to collect the body of the loop while waiting
         * for the corresponding .endfor.
         */
        GLM_FOR_BODY,

        /*
         * Return the next line that starts with a dot.
         * Backslash line continuations are folded into a single space.
         * A trailing comment, if any, is discarded.
         *
         * Used in .if directives to skip over irrelevant branches while
         * waiting for the corresponding .endif.
         */
        GLM_DOT
} GetLineMode;

/* Return the next "interesting" logical line from the current file. */
static char *
ParseGetLine(GetLineMode mode)
{
        IFile *curFile = CurFile();
        char *line;
        char *line_end;
        char *firstBackslash;
        char *firstComment;

        for (;;) {
                ParseRawLineResult res = ParseRawLine(curFile,
                    &line, &line_end, &firstBackslash, &firstComment);
                if (res == PRLR_ERROR)
                        return NULL;

                if (line_end == line || firstComment == line) {
                        if (res == PRLR_EOF)
                                return NULL;
                        if (mode != GLM_FOR_BODY)
                                continue;
                }

                /* We now have a line of data */
                assert(ch_isspace(*line_end));
                *line_end = '\0';

                if (mode == GLM_FOR_BODY)
                        return line;    /* Don't join the physical lines. */

                if (mode == GLM_DOT && line[0] != '.')
                        continue;
                break;
        }

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

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

        /* Remove escapes from '\n' and '#' */
        UnescapeBackslash(line, firstBackslash);

        return line;
}

static Boolean
ParseSkippedBranches(void)
{
        char *line;

        while ((line = ParseGetLine(GLM_DOT)) != NULL) {
                if (Cond_EvalLine(line) == COND_PARSE)
                        break;
                /*
                 * TODO: Check for typos in .elif directives
                 * such as .elsif or .elseif.
                 *
                 * This check will probably duplicate some of
                 * the code in ParseLine.  Most of the code
                 * there cannot apply, only ParseVarassign and
                 * ParseDependency can, and to prevent code
                 * duplication, these would need to be called
                 * with a flag called onlyCheckSyntax.
                 *
                 * See directive-elif.mk for details.
                 */
        }

        return line != NULL;
}

static Boolean
ParseForLoop(const char *line)
{
        int rval;
        int firstLineno;

        rval = For_Eval(line);
        if (rval == 0)
                return FALSE;   /* Not a .for line */
        if (rval < 0)
                return TRUE;    /* Syntax error - error printed, ignore line */

        firstLineno = CurFile()->lineno;

        /* Accumulate loop lines until matching .endfor */
        do {
                line = ParseGetLine(GLM_FOR_BODY);
                if (line == NULL) {
                        Parse_Error(PARSE_FATAL,
                            "Unexpected end of file in for loop.");
                        break;
                }
        } while (For_Accum(line));

        For_Run(firstLineno);   /* Stash each iteration as a new 'input file' */

        return TRUE;            /* Read next line from for-loop buffer */
}

/*
 * Read an entire line from the input file.
 *
 * Empty lines, .if and .for are completely handled by this function,
 * leaving only variable assignments, other directives, dependency lines
 * and shell commands to the caller.
 *
 * Results:
 *      A line without its newline and without any trailing whitespace,
 *      or NULL.
 */
static char *
ParseReadLine(void)
{
        char *line;

        for (;;) {
                line = ParseGetLine(GLM_NONEMPTY);
                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:
                        if (!ParseSkippedBranches())
                                return NULL;
                        continue;
                case COND_PARSE:
                        continue;
                case COND_INVALID:      /* Not a conditional line */
                        if (ParseForLoop(line))
                                continue;
                        break;
                }
                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
        }
}

MAKE_INLINE Boolean
IsDirective(const char *dir, size_t dirlen, const char *name)
{
        return dirlen == strlen(name) && memcmp(dir, name, dirlen) == 0;
}

/*
 * See if the line starts with one of the known directives, and if so, handle
 * the directive.
 */
static Boolean
ParseDirective(char *line)
{
        char *cp = line + 1;
        const char *dir, *arg;
        size_t dirlen;

        pp_skip_whitespace(&cp);
        if (IsInclude(cp, FALSE)) {
                ParseDoInclude(cp);
                return TRUE;
        }

        dir = cp;
        while (ch_isalpha(*cp) || *cp == '-')
                cp++;
        dirlen = (size_t)(cp - dir);

        if (*cp != '\0' && !ch_isspace(*cp))
                return FALSE;

        pp_skip_whitespace(&cp);
        arg = cp;

        if (IsDirective(dir, dirlen, "undef")) {
                Var_Undef(cp);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "export")) {
                Var_Export(VEM_PLAIN, arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "export-env")) {
                Var_Export(VEM_ENV, arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "export-literal")) {
                Var_Export(VEM_LITERAL, arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "unexport")) {
                Var_UnExport(FALSE, arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "unexport-env")) {
                Var_UnExport(TRUE, arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "info")) {
                ParseMessage(PARSE_INFO, "info", arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "warning")) {
                ParseMessage(PARSE_WARNING, "warning", arg);
                return TRUE;
        } else if (IsDirective(dir, dirlen, "error")) {
                ParseMessage(PARSE_FATAL, "error", arg);
                return TRUE;
        }
        return FALSE;
}

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

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

        FinishDependencyGroup();
        Parse_DoVar(&var, SCOPE_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.strict ? VARE_WANTRES : VARE_WANTRES | VARE_UNDEFERR;
        (void)Var_Subst(line, SCOPE_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)
{
        /*
         * 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'.
         */
        if (line[0] == '.' && ParseDirective(line))
                return;

        if (line[0] == '\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_readMore, 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.");

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

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

int
Parse_GetFatals(void)
{
        return fatals;
}