etc/protocols - sync with NetBSD-8

[minix.git] / usr.bin / make / parse.c

/*      $NetBSD: parse.c,v 1.204 2014/09/18 08:06:13 dholland 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.
 */

#ifndef MAKE_NATIVE
static char rcsid[] = "$NetBSD: parse.c,v 1.204 2014/09/18 08:06:13 dholland Exp $";
#else
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)parse.c     8.3 (Berkeley) 3/19/94";
#else
__RCSID("$NetBSD: parse.c,v 1.204 2014/09/18 08:06:13 dholland Exp $");
#endif
#endif /* not lint */
#endif

/*-
 * parse.c --
 *      Functions to parse a makefile.
 *
 *      One function, Parse_Init, must be called before any functions
 *      in this module are used. After that, the function Parse_File is the
 *      main entry point and controls most of the other functions in this
 *      module.
 *
 *      Most important structures are kept in Lsts. Directories for
 *      the .include "..." function are kept in the 'parseIncPath' Lst, while
 *      those for the .include <...> are kept in the 'sysIncPath' Lst. The
 *      targets currently being defined are kept in the 'targets' Lst.
 *
 *      The variables 'fname' and 'lineno' are used to track the name
 *      of the current file and the line number in that file so that error
 *      messages can be more meaningful.
 *
 * Interface:
 *      Parse_Init                  Initialization function which must be
 *                                  called before anything else in this module
 *                                  is used.
 *
 *      Parse_End                   Cleanup the module
 *
 *      Parse_File                  Function used to parse a makefile. It must
 *                                  be given the name of the file, which should
 *                                  already have been opened, and a function
 *                                  to call to read a character from the file.
 *
 *      Parse_IsVar                 Returns 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                 Function called when an error occurs in
 *                                  parsing. Used by the variable and
 *                                  conditional modules.
 *      Parse_MainName              Returns a Lst of the main target to create.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>

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

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

////////////////////////////////////////////////////////////
// types and constants

/*
 * Structure for a file being read ("included file")
 */
typedef struct IFile {
    char            *fname;         /* name of file */
    int             lineno;         /* current line number in file */
    int             first_lineno;   /* line number of start of text */
    int             cond_depth;     /* 'if' nesting when file opened */
    char            *P_str;         /* point to base of string buffer */
    char            *P_ptr;         /* point to next char of string buffer */
    char            *P_end;         /* point to the end of string buffer */
    char            *(*nextbuf)(void *, size_t *); /* Function to get more data */
    void            *nextbuf_arg;   /* Opaque arg for nextbuf() */
    struct loadedfile *lf;          /* loadedfile object, if any */
} IFile;


/*
 * These values are returned by ParseEOF to tell Parse_File whether to
 * CONTINUE parsing, i.e. it had only reached the end of an include file,
 * or if it's DONE.
 */
#define CONTINUE        1
#define DONE            0

/*
 * Tokens for target attributes
 */
typedef enum {
    Begin,          /* .BEGIN */
    Default,        /* .DEFAULT */
    End,            /* .END */
    dotError,       /* .ERROR */
    Ignore,         /* .IGNORE */
    Includes,       /* .INCLUDES */
    Interrupt,      /* .INTERRUPT */
    Libs,           /* .LIBS */
    Meta,           /* .META */
    MFlags,         /* .MFLAGS or .MAKEFLAGS */
    Main,           /* .MAIN and we don't have anything user-specified to
                     * make */
    NoExport,       /* .NOEXPORT */
    NoMeta,         /* .NOMETA */
    NoMetaCmp,      /* .NOMETA_CMP */
    NoPath,         /* .NOPATH */
    Not,            /* Not special */
    NotParallel,    /* .NOTPARALLEL */
    Null,           /* .NULL */
    ExObjdir,       /* .OBJDIR */
    Order,          /* .ORDER */
    Parallel,       /* .PARALLEL */
    ExPath,         /* .PATH */
    Phony,          /* .PHONY */
#ifdef POSIX
    Posix,          /* .POSIX */
#endif
    Precious,       /* .PRECIOUS */
    ExShell,        /* .SHELL */
    Silent,         /* .SILENT */
    SingleShell,    /* .SINGLESHELL */
    Stale,          /* .STALE */
    Suffixes,       /* .SUFFIXES */
    Wait,           /* .WAIT */
    Attribute       /* Generic attribute */
} ParseSpecial;

/*
 * Other tokens
 */
#define LPAREN  '('
#define RPAREN  ')'


////////////////////////////////////////////////////////////
// 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

/* targets we're working on */
static Lst targets;

#ifdef CLEANUP
/* command lines for targets */
static Lst targCmds;
#endif

/*
 * specType contains the SPECial TYPE of the current target. It is
 * Not if the target is unspecial. If it *is* special, however, the children
 * are linked as children of the parent but not vice versa. This variable is
 * set in ParseDoDependency
 */
static ParseSpecial specType;

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

////////////////////////////////////////////////////////////
// parser state

/* true if currently in a dependency line or its commands */
static Boolean inLine;

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

/*
 * Variables for doing includes
 */

/* current file being read */
static IFile *curFile;

/* stack of IFiles generated by .includes */
static Lst includes;

/* include paths (lists of directories) */
Lst parseIncPath;       /* dirs for "..." includes */
Lst sysIncPath;         /* dirs for <...> includes */
Lst defIncPath;         /* 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 ("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 */
    int           op;           /* Operator when used as a source */
} parseKeywords[] = {
{ ".BEGIN",       Begin,        0 },
{ ".DEFAULT",     Default,      0 },
{ ".END",         End,          0 },
{ ".ERROR",       dotError,     0 },
{ ".EXEC",        Attribute,    OP_EXEC },
{ ".IGNORE",      Ignore,       OP_IGNORE },
{ ".INCLUDES",    Includes,     0 },
{ ".INTERRUPT",   Interrupt,    0 },
{ ".INVISIBLE",   Attribute,    OP_INVISIBLE },
{ ".JOIN",        Attribute,    OP_JOIN },
{ ".LIBS",        Libs,         0 },
{ ".MADE",        Attribute,    OP_MADE },
{ ".MAIN",        Main,         0 },
{ ".MAKE",        Attribute,    OP_MAKE },
{ ".MAKEFLAGS",   MFlags,       0 },
{ ".META",        Meta,         OP_META },
{ ".MFLAGS",      MFlags,       0 },
{ ".NOMETA",      NoMeta,       OP_NOMETA },
{ ".NOMETA_CMP",  NoMetaCmp,    OP_NOMETA_CMP },
{ ".NOPATH",      NoPath,       OP_NOPATH },
{ ".NOTMAIN",     Attribute,    OP_NOTMAIN },
{ ".NOTPARALLEL", NotParallel,  0 },
{ ".NO_PARALLEL", NotParallel,  0 },
{ ".NULL",        Null,         0 },
{ ".OBJDIR",      ExObjdir,     0 },
{ ".OPTIONAL",    Attribute,    OP_OPTIONAL },
{ ".ORDER",       Order,        0 },
{ ".PARALLEL",    Parallel,     0 },
{ ".PATH",        ExPath,       0 },
{ ".PHONY",       Phony,        OP_PHONY },
#ifdef POSIX
{ ".POSIX",       Posix,        0 },
#endif
{ ".PRECIOUS",    Precious,     OP_PRECIOUS },
{ ".RECURSIVE",   Attribute,    OP_MAKE },
{ ".SHELL",       ExShell,      0 },
{ ".SILENT",      Silent,       OP_SILENT },
{ ".SINGLESHELL", SingleShell,  0 },
{ ".STALE",       Stale,        0 },
{ ".SUFFIXES",    Suffixes,     0 },
{ ".USE",         Attribute,    OP_USE },
{ ".USEBEFORE",   Attribute,    OP_USEBEFORE },
{ ".WAIT",        Wait,         0 },
};

////////////////////////////////////////////////////////////
// local functions

static int ParseIsEscaped(const char *, const char *);
static void ParseErrorInternal(const char *, size_t, int, const char *, ...)
    MAKE_ATTR_PRINTFLIKE(4,5);
static void ParseVErrorInternal(FILE *, const char *, size_t, int, const char *, va_list)
    MAKE_ATTR_PRINTFLIKE(5, 0);
static int ParseFindKeyword(const char *);
static int ParseLinkSrc(void *, void *);
static int ParseDoOp(void *, void *);
static void ParseDoSrc(int, const char *);
static int ParseFindMain(void *, void *);
static int ParseAddDir(void *, void *);
static int ParseClearPath(void *, void *);
static void ParseDoDependency(char *);
static int ParseAddCmd(void *, void *);
static void ParseHasCommands(void *);
static void ParseDoInclude(char *);
static void ParseSetParseFile(const char *);
static void ParseSetIncludedFile(void);
#ifdef SYSVINCLUDE
static void ParseTraditionalInclude(char *);
#endif
#ifdef GMAKEEXPORT
static void ParseGmakeExport(char *);
#endif
static int ParseEOF(void);
static char *ParseReadLine(void);
static void ParseFinishLine(void);
static void ParseMark(GNode *);

////////////////////////////////////////////////////////////
// file loader

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

/*
 * Constructor/destructor for loadedfile
 */
static struct loadedfile *
loadedfile_create(const char *path)
{
        struct loadedfile *lf;

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

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

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

        if (lf->used) {
                return NULL;
        }
        lf->used = TRUE;
        *len = lf->len;
        return lf->buf;
}

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

        if (fstat(fd, &st) < 0) {
                return FAILURE;
        }

        if (!S_ISREG(st.st_mode)) {
                return FAILURE;
        }

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

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

/*
 * 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 and (to insure against fd leaks)
 * assert that the caller passed in -1.
 */
static struct loadedfile *
loadfile(const char *path, int fd)
{
        struct loadedfile *lf;
        long pagesize;
        ssize_t result;
        size_t bufpos;

        lf = loadedfile_create(path);

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

        if (load_getsize(fd, &lf->len) == SUCCESS) {
                /* found a size, try mmap */
                pagesize = sysconf(_SC_PAGESIZE);
                if (pagesize <= 0) {
                        pagesize = 0x1000;
                }
                /* round size up to a page */
                lf->maplen = pagesize * ((lf->len + pagesize - 1)/pagesize);

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

                /*
                 * FUTURE: remove PROT_WRITE when the parser no longer
                 * needs to scribble on the input.
                 */
                lf->buf = mmap(NULL, lf->maplen, PROT_READ|PROT_WRITE,
                               MAP_FILE|MAP_COPY, fd, 0);
                if (lf->buf != MAP_FAILED) {
                        /* succeeded */
                        if (lf->len == lf->maplen && lf->buf[lf->len - 1] != '\n') {
                                char *b = malloc(lf->len + 1);
                                b[lf->len] = '\n';
                                memcpy(b, lf->buf, lf->len++);
                                munmap(lf->buf, lf->maplen);
                                lf->maplen = 0;
                                lf->buf = b;
                        }
                        goto done;
                }
        }

        /* cannot mmap; load the traditional way */

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

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

        /* truncate malloc region to actual length (maybe not useful) */
        if (lf->len > 0) {
                lf->buf = bmake_realloc(lf->buf, lf->len);
        }

done:
        if (path != NULL) {
                close(fd);
        }
        return lf;
}

////////////////////////////////////////////////////////////
// old code

/*-
 *----------------------------------------------------------------------
 * ParseIsEscaped --
 *      Check if the current character is escaped on the current line
 *
 * Results:
 *      0 if the character is not backslash escaped, 1 otherwise
 *
 * Side Effects:
 *      None
 *----------------------------------------------------------------------
 */
static int
ParseIsEscaped(const char *line, const char *c)
{
    int active = 0;
    for (;;) {
        if (line == c)
            return active;
        if (*--c != '\\')
            return active;
        active = !active;
    }
}

/*-
 *----------------------------------------------------------------------
 * ParseFindKeyword --
 *      Look in the table of keywords for one matching the given string.
 *
 * Input:
 *      str             String to find
 *
 * Results:
 *      The index of the keyword, or -1 if it isn't there.
 *
 * Side Effects:
 *      None
 *----------------------------------------------------------------------
 */
static int
ParseFindKeyword(const char *str)
{
    int    start, end, cur;
    int    diff;

    start = 0;
    end = (sizeof(parseKeywords)/sizeof(parseKeywords[0])) - 1;

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

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

/*-
 * ParseVErrorInternal  --
 *      Error message abort function for parsing. Prints out the context
 *      of the error (line number and file) as well as the message with
 *      two optional arguments.
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      "fatals" is incremented if the level is PARSE_FATAL.
 */
/* VARARGS */
static void
ParseVErrorInternal(FILE *f, const char *cfname, size_t clineno, int type,
    const char *fmt, va_list ap)
{
        static Boolean fatal_warning_error_printed = FALSE;

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

        if (cfname != NULL) {
                (void)fprintf(f, "\"");
                if (*cfname != '/' && strcmp(cfname, "(stdin)") != 0) {
                        char *cp;
                        const char *dir;

                        /*
                         * Nothing is more annoying than not knowing
                         * which Makefile is the culprit.
                         */
                        dir = Var_Value(".PARSEDIR", VAR_GLOBAL, &cp);
                        if (dir == NULL || *dir == '\0' ||
                            (*dir == '.' && dir[1] == '\0'))
                                dir = Var_Value(".CURDIR", VAR_GLOBAL, &cp);
                        if (dir == NULL)
                                dir = ".";

                        (void)fprintf(f, "%s/%s", dir, cfname);
                } else
                        (void)fprintf(f, "%s", cfname);

                (void)fprintf(f, "\" line %d: ", (int)clineno);
        }
        if (type == PARSE_WARNING)
                (void)fprintf(f, "warning: ");
        (void)vfprintf(f, fmt, ap);
        (void)fprintf(f, "\n");
        (void)fflush(f);
        if (type == PARSE_FATAL || parseWarnFatal)
                fatals += 1;
        if (parseWarnFatal && !fatal_warning_error_printed) {
                Error("parsing warnings being treated as errors");
                fatal_warning_error_printed = TRUE;
        }
}

/*-
 * ParseErrorInternal  --
 *      Error function
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      None
 */
/* VARARGS */
static void
ParseErrorInternal(const char *cfname, size_t clineno, int type,
    const char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        (void)fflush(stdout);
        ParseVErrorInternal(stderr, cfname, clineno, type, fmt, ap);
        va_end(ap);

        if (debug_file != stderr && debug_file != stdout) {
                va_start(ap, fmt);
                ParseVErrorInternal(debug_file, cfname, clineno, type, fmt, ap);
                va_end(ap);
        }
}

/*-
 * Parse_Error  --
 *      External interface to ParseErrorInternal; uses the default filename
 *      Line number.
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      None
 */
/* VARARGS */
void
Parse_Error(int type, const char *fmt, ...)
{
        va_list ap;
        const char *fname;
        size_t lineno;

        if (curFile == NULL) {
                fname = NULL;
                lineno = 0;
        } else {
                fname = curFile->fname;
                lineno = curFile->lineno;
        }

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

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


/*
 * ParseMessage
 *      Parse a .info .warning or .error directive
 *
 *      The input is the line minus the ".".  We substitute
 *      variables, print the message and exit(1) (for .error) or just print
 *      a warning if the directive is malformed.
 */
static Boolean
ParseMessage(char *line)
{
    int mtype;

    switch(*line) {
    case 'i':
        mtype = 0;
        break;
    case 'w':
        mtype = PARSE_WARNING;
        break;
    case 'e':
        mtype = PARSE_FATAL;
        break;
    default:
        Parse_Error(PARSE_WARNING, "invalid syntax: \".%s\"", line);
        return FALSE;
    }

    while (isalpha((u_char)*line))
        line++;
    if (!isspace((u_char)*line))
        return FALSE;                   /* not for us */
    while (isspace((u_char)*line))
        line++;

    line = Var_Subst(NULL, line, VAR_CMD, 0);
    Parse_Error(mtype, "%s", line);
    free(line);

    if (mtype == PARSE_FATAL) {
        /* Terminate immediately. */
        exit(1);
    }
    return TRUE;
}

/*-
 *---------------------------------------------------------------------
 * ParseLinkSrc  --
 *      Link the parent node to its new child. Used in a Lst_ForEach by
 *      ParseDoDependency. If the specType isn't 'Not', the parent
 *      isn't linked as a parent of the child.
 *
 * Input:
 *      pgnp            The parent node
 *      cgpn            The child node
 *
 * Results:
 *      Always = 0
 *
 * Side Effects:
 *      New elements are added to the parents list of cgn and the
 *      children list of cgn. the unmade field of pgn is updated
 *      to reflect the additional child.
 *---------------------------------------------------------------------
 */
static int
ParseLinkSrc(void *pgnp, void *cgnp)
{
    GNode          *pgn = (GNode *)pgnp;
    GNode          *cgn = (GNode *)cgnp;

    if ((pgn->type & OP_DOUBLEDEP) && !Lst_IsEmpty (pgn->cohorts))
        pgn = (GNode *)Lst_Datum(Lst_Last(pgn->cohorts));
    (void)Lst_AtEnd(pgn->children, cgn);
    if (specType == Not)
            (void)Lst_AtEnd(cgn->parents, pgn);
    pgn->unmade += 1;
    if (DEBUG(PARSE)) {
        fprintf(debug_file, "# %s: added child %s - %s\n", __func__,
            pgn->name, cgn->name);
        Targ_PrintNode(pgn, 0);
        Targ_PrintNode(cgn, 0);
    }
    return (0);
}

/*-
 *---------------------------------------------------------------------
 * ParseDoOp  --
 *      Apply the parsed operator to the given target node. Used in a
 *      Lst_ForEach call by ParseDoDependency once all targets have
 *      been found and their operator parsed. If the previous and new
 *      operators are incompatible, a major error is taken.
 *
 * Input:
 *      gnp             The node to which the operator is to be applied
 *      opp             The operator to apply
 *
 * Results:
 *      Always 0
 *
 * Side Effects:
 *      The type field of the node is altered to reflect any new bits in
 *      the op.
 *---------------------------------------------------------------------
 */
static int
ParseDoOp(void *gnp, void *opp)
{
    GNode          *gn = (GNode *)gnp;
    int             op = *(int *)opp;
    /*
     * If the dependency mask of the operator and the node don't match and
     * the node has actually had an operator applied to it before, and
     * the operator actually has some dependency information in it, complain.
     */
    if (((op & OP_OPMASK) != (gn->type & OP_OPMASK)) &&
        !OP_NOP(gn->type) && !OP_NOP(op))
    {
        Parse_Error(PARSE_FATAL, "Inconsistent operator for %s", gn->name);
        return (1);
    }

    if ((op == OP_DOUBLEDEP) && ((gn->type & OP_OPMASK) == OP_DOUBLEDEP)) {
        /*
         * If the node was the object of a :: operator, we need to create a
         * new instance of it for the children and commands on this dependency
         * line. 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_FindNode(gn->name, TARG_NOHASH);
        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;
        (void)Lst_AtEnd(gn->cohorts, cohort);
        cohort->centurion = gn;
        gn->unmade_cohorts += 1;
        snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
                gn->unmade_cohorts);
    } 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 (0);
}

/*-
 *---------------------------------------------------------------------
 * ParseDoSrc  --
 *      Given the name of a source, figure out if it is an attribute
 *      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 and apply it if so. Otherwise, make the
 *      source be a child of the targets in the list 'targets'
 *
 * Input:
 *      tOp             operator (if any) from special targets
 *      src             name of the source to handle
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      Operator bits may be added to the list of targets or to the source.
 *      The targets may have a new source added to their lists of children.
 *---------------------------------------------------------------------
 */
static void
ParseDoSrc(int tOp, const char *src)
{
    GNode       *gn = NULL;
    static int wait_number = 0;
    char wait_src[16];

    if (*src == '.' && isupper ((unsigned char)src[1])) {
        int keywd = ParseFindKeyword(src);
        if (keywd != -1) {
            int op = parseKeywords[keywd].op;
            if (op != 0) {
                Lst_ForEach(targets, ParseDoOp, &op);
                return;
            }
            if (parseKeywords[keywd].spec == Wait) {
                /*
                 * We add a .WAIT node in the dependency list.
                 * After any dynamic dependencies (and filename globbing)
                 * have happened, it is given a dependency on the each
                 * previous child back to and 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 diag).
                 */
                snprintf(wait_src, sizeof wait_src, ".WAIT_%u", ++wait_number);
                gn = Targ_FindNode(wait_src, TARG_NOHASH);
                if (doing_depend)
                    ParseMark(gn);
                gn->type = OP_WAIT | OP_PHONY | OP_DEPENDS | OP_NOTMAIN;
                Lst_ForEach(targets, ParseLinkSrc, gn);
                return;
            }
        }
    }

    switch (specType) {
    case Main:
        /*
         * If we have noted the existence of a .MAIN, it means we need
         * to add the sources of said target to the list of things
         * to create. The string 'src' is likely to be free, so we
         * must make a new copy of it. Note that this will only be
         * invoked if the user didn't specify a target on the command
         * line. This is to allow #ifmake's to succeed, or something...
         */
        (void)Lst_AtEnd(create, bmake_strdup(src));
        /*
         * Add the name to the .TARGETS variable as well, so the user can
         * employ that, if desired.
         */
        Var_Append(".TARGETS", src, VAR_GLOBAL);
        return;

    case Order:
        /*
         * Create proper predecessor/successor links between the previous
         * source and the current one.
         */
        gn = Targ_FindNode(src, TARG_CREATE);
        if (doing_depend)
            ParseMark(gn);
        if (predecessor != NULL) {
            (void)Lst_AtEnd(predecessor->order_succ, gn);
            (void)Lst_AtEnd(gn->order_pred, predecessor);
            if (DEBUG(PARSE)) {
                fprintf(debug_file, "# %s: added Order dependency %s - %s\n",
                    __func__, predecessor->name, gn->name);
                Targ_PrintNode(predecessor, 0);
                Targ_PrintNode(gn, 0);
            }
        }
        /*
         * The current source now becomes the predecessor for the next one.
         */
        predecessor = gn;
        break;

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

        /* Find/create the 'src' node and attach to all targets */
        gn = Targ_FindNode(src, TARG_CREATE);
        if (doing_depend)
            ParseMark(gn);
        if (tOp) {
            gn->type |= tOp;
        } else {
            Lst_ForEach(targets, ParseLinkSrc, gn);
        }
        break;
    }
}

/*-
 *-----------------------------------------------------------------------
 * ParseFindMain --
 *      Find a real target in the list and set it to be the main one.
 *      Called by ParseDoDependency when a main target hasn't been found
 *      yet.
 *
 * Input:
 *      gnp             Node to examine
 *
 * Results:
 *      0 if main not found yet, 1 if it is.
 *
 * Side Effects:
 *      mainNode is changed and Targ_SetMain is called.
 *
 *-----------------------------------------------------------------------
 */
static int
ParseFindMain(void *gnp, void *dummy)
{
    GNode         *gn = (GNode *)gnp;
    if ((gn->type & OP_NOTARGET) == 0) {
        mainNode = gn;
        Targ_SetMain(gn);
        return (dummy ? 1 : 1);
    } else {
        return (dummy ? 0 : 0);
    }
}

/*-
 *-----------------------------------------------------------------------
 * ParseAddDir --
 *      Front-end for Dir_AddDir to make sure Lst_ForEach keeps going
 *
 * Results:
 *      === 0
 *
 * Side Effects:
 *      See Dir_AddDir.
 *
 *-----------------------------------------------------------------------
 */
static int
ParseAddDir(void *path, void *name)
{
    (void)Dir_AddDir((Lst) path, (char *)name);
    return(0);
}

/*-
 *-----------------------------------------------------------------------
 * ParseClearPath --
 *      Front-end for Dir_ClearPath to make sure Lst_ForEach keeps going
 *
 * Results:
 *      === 0
 *
 * Side Effects:
 *      See Dir_ClearPath
 *
 *-----------------------------------------------------------------------
 */
static int
ParseClearPath(void *path, void *dummy)
{
    Dir_ClearPath((Lst) path);
    return(dummy ? 0 : 0);
}

/*-
 *---------------------------------------------------------------------
 * ParseDoDependency  --
 *      Parse the dependency line in line.
 *
 * Input:
 *      line            the line to parse
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      The nodes of the sources are linked as children to the nodes of the
 *      targets. Some nodes may be created.
 *
 *      We parse a dependency line by first extracting words from the line and
 * finding nodes in the list of all targets with that name. This is done
 * until a character is encountered which is an operator character. Currently
 * these are only ! and :. At this point the operator is parsed and the
 * pointer into the line advanced until the first source is encountered.
 *      The parsed operator is applied to each node in the 'targets' list,
 * which is where the nodes found for the targets are kept, by means of
 * the ParseDoOp function.
 *      The sources are read in much the same way as the targets were except
 * that now they are expanded using the wildcarding scheme of the C-Shell
 * and all instances of the resulting words in the list of all targets
 * are found. Each of the resulting nodes is then linked to each of the
 * targets as one of its children.
 *      Certain targets are handled specially. These are the ones detailed
 * by the specType variable.
 *      The storing of transformation rules 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.
 *---------------------------------------------------------------------
 */
static void
ParseDoDependency(char *line)
{
    char           *cp;         /* our current position */
    GNode          *gn = NULL;  /* a general purpose temporary node */
    int             op;         /* the operator on the line */
    char            savec;      /* a place to save a character */
    Lst             paths;      /* List of search paths to alter when parsing
                                 * a list of .PATH targets */
    int             tOp;        /* operator from special target */
    Lst             sources;    /* list of archive source names after
                                 * expansion */
    Lst             curTargs;   /* list of target names to be found and added
                                 * to the targets list */
    char           *lstart = line;

    if (DEBUG(PARSE))
        fprintf(debug_file, "ParseDoDependency(%s)\n", line);
    tOp = 0;

    specType = Not;
    paths = NULL;

    curTargs = Lst_Init(FALSE);

    /*
     * First, grind through the targets.
     */

    do {
        /*
         * 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. */
        for (cp = line; *cp && (ParseIsEscaped(lstart, cp) ||
                     !(isspace((unsigned char)*cp) ||
                         *cp == '!' || *cp == ':' || *cp == LPAREN));
                 cp++) {
            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.
                 */
                int     length;
                void    *freeIt;

                (void)Var_Parse(cp, VAR_CMD, TRUE, &length, &freeIt);
                if (freeIt)
                    free(freeIt);
                cp += length-1;
            }
        }

        /*
         * 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 == LPAREN) {
            /*
             * 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 SUCCESS if all
             * went well and FAILURE if there was an error in the
             * specification. On error, line should remain untouched.
             */
            if (Arch_ParseArchive(&line, targets, VAR_CMD) != SUCCESS) {
                Parse_Error(PARSE_FATAL,
                             "Error in archive specification: \"%s\"", line);
                goto out;
            } else {
                /* Done with this word; on to the next. */
                continue;
            }
        }

        if (!*cp) {
            /*
             * 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.
             */
            if ((strncmp(line, "<<<<<<", 6) == 0) ||
                (strncmp(line, "======", 6) == 0) ||
                (strncmp(line, ">>>>>>", 6) == 0))
                Parse_Error(PARSE_FATAL,
                    "Makefile appears to contain unresolved cvs/rcs/??? merge conflicts");
            else
                Parse_Error(PARSE_FATAL, lstart[0] == '.' ? "Unknown directive"
                                     : "Need an operator");
            goto out;
        }

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

        /*
         * Got the word. See if it's a special target and if so set
         * specType to match it.
         */
        if (*line == '.' && isupper ((unsigned char)line[1])) {
            /*
             * See if the target is a special target that must have it
             * or its sources handled specially.
             */
            int keywd = ParseFindKeyword(line);
            if (keywd != -1) {
                if (specType == ExPath && parseKeywords[keywd].spec != ExPath) {
                    Parse_Error(PARSE_FATAL, "Mismatched special targets");
                    goto out;
                }

                specType = parseKeywords[keywd].spec;
                tOp = parseKeywords[keywd].op;

                /*
                 * Certain special targets have special semantics:
                 *      .PATH           Have to set the dirSearchPath
                 *                      variable too
                 *      .MAIN           Its sources are only used if
                 *                      nothing has been specified to
                 *                      create.
                 *      .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, so we
                 *                      create it, set OP_NOTMAIN and
                 *                      add it to the list, setting
                 *                      DEFAULT to the new node for
                 *                      later use. 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.
                 *      .PHONY          The list of targets
                 *      .NOPATH         Don't search for file in the path
                 *      .STALE
                 *      .BEGIN
                 *      .END
                 *      .ERROR
                 *      .INTERRUPT      Are not to be considered the
                 *                      main target.
                 *      .NOTPARALLEL    Make only one target at a time.
                 *      .SINGLESHELL    Create a shell for each command.
                 *      .ORDER          Must set initial predecessor to NULL
                 */
                switch (specType) {
                case ExPath:
                    if (paths == NULL) {
                        paths = Lst_Init(FALSE);
                    }
                    (void)Lst_AtEnd(paths, dirSearchPath);
                    break;
                case Main:
                    if (!Lst_IsEmpty(create)) {
                        specType = Not;
                    }
                    break;
                case Begin:
                case End:
                case Stale:
                case dotError:
                case Interrupt:
                    gn = Targ_FindNode(line, TARG_CREATE);
                    if (doing_depend)
                        ParseMark(gn);
                    gn->type |= OP_NOTMAIN|OP_SPECIAL;
                    (void)Lst_AtEnd(targets, gn);
                    break;
                case Default:
                    gn = Targ_NewGN(".DEFAULT");
                    gn->type |= (OP_NOTMAIN|OP_TRANSFORM);
                    (void)Lst_AtEnd(targets, gn);
                    DEFAULT = gn;
                    break;
                case NotParallel:
                    maxJobs = 1;
                    break;
                case SingleShell:
                    compatMake = TRUE;
                    break;
                case Order:
                    predecessor = NULL;
                    break;
                default:
                    break;
                }
            } else if (strncmp(line, ".PATH", 5) == 0) {
                /*
                 * .PATH<suffix> has to be handled specially.
                 * Call on the suffix module to give us a path to
                 * modify.
                 */
                Lst     path;

                specType = ExPath;
                path = Suff_GetPath(&line[5]);
                if (path == NULL) {
                    Parse_Error(PARSE_FATAL,
                                 "Suffix '%s' not defined (yet)",
                                 &line[5]);
                    goto out;
                } else {
                    if (paths == NULL) {
                        paths = Lst_Init(FALSE);
                    }
                    (void)Lst_AtEnd(paths, path);
                }
            }
        }

        /*
         * Have word in line. Get or create its node and stick it at
         * the end of the targets list
         */
        if ((specType == Not) && (*line != '\0')) {
            if (Dir_HasWildcards(line)) {
                /*
                 * Targets are to be sought only in the current directory,
                 * so create an empty path for the thing. Note we need to
                 * use Dir_Destroy in the destruction of the path as the
                 * Dir module could have added a directory to the path...
                 */
                Lst         emptyPath = Lst_Init(FALSE);

                Dir_Expand(line, emptyPath, curTargs);

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

            /* Apply the targets. */

            while(!Lst_IsEmpty(curTargs)) {
                char    *targName = (char *)Lst_DeQueue(curTargs);

                if (!Suff_IsTransform (targName)) {
                    gn = Targ_FindNode(targName, TARG_CREATE);
                } else {
                    gn = Suff_AddTransform(targName);
                }
                if (doing_depend)
                    ParseMark(gn);

                (void)Lst_AtEnd(targets, gn);
            }
        } else if (specType == ExPath && *line != '.' && *line != '\0') {
            Parse_Error(PARSE_WARNING, "Extra target (%s) ignored", line);
        }

        /* 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 (specType != Not && specType != ExPath) {
            Boolean warning = FALSE;

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

    /*
     * Don't need the list of target names anymore...
     */
    Lst_Destroy(curTargs, NULL);
    curTargs = NULL;

    if (!Lst_IsEmpty(targets)) {
        switch(specType) {
            default:
                Parse_Error(PARSE_WARNING, "Special and mundane targets don't mix. Mundane ones ignored");
                break;
            case Default:
            case Stale:
            case Begin:
            case End:
            case dotError:
            case Interrupt:
                /*
                 * These four create nodes on which to hang commands, so
                 * targets shouldn't be empty...
                 */
            case Not:
                /*
                 * Nothing special here -- targets can be empty if it wants.
                 */
                break;
        }
    }

    /*
     * Have now parsed all the target names. Must parse the operator next. The
     * result is left in  op .
     */
    if (*cp == '!') {
        op = OP_FORCE;
    } else if (*cp == ':') {
        if (cp[1] == ':') {
            op = OP_DOUBLEDEP;
            cp++;
        } else {
            op = OP_DEPENDS;
        }
    } else {
        Parse_Error(PARSE_FATAL, lstart[0] == '.' ? "Unknown directive"
                    : "Missing dependency operator");
        goto out;
    }

    /* Advance beyond the operator */
    cp++;

    /*
     * 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.
     */
    Lst_ForEach(targets, ParseDoOp, &op);

    /*
     * Onward to the sources.
     *
     * LINE will now point to the first source word, if any, or the
     * end of the string if not.
     */
    while (*cp && isspace ((unsigned char)*cp)) {
        cp++;
    }
    line = cp;

    /*
     * 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) {
        switch (specType) {
            case Suffixes:
                Suff_ClearSuffixes();
                break;
            case Precious:
                allPrecious = TRUE;
                break;
            case Ignore:
                ignoreErrors = TRUE;
                break;
            case Silent:
                beSilent = TRUE;
                break;
            case ExPath:
                Lst_ForEach(paths, ParseClearPath, NULL);
                Dir_SetPATH();
                break;
#ifdef POSIX
            case Posix:
                Var_Set("%POSIX", "1003.2", VAR_GLOBAL, 0);
                break;
#endif
            default:
                break;
        }
    } else if (specType == 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 == ExShell) {
        if (Job_ParseShell(line) != SUCCESS) {
            Parse_Error(PARSE_FATAL, "improper shell specification");
            goto out;
        }
        *line = '\0';
    } else if ((specType == NotParallel) || (specType == SingleShell)) {
        *line = '\0';
    }

    /*
     * NOW GO FOR THE SOURCES
     */
    if ((specType == Suffixes) || (specType == ExPath) ||
        (specType == Includes) || (specType == Libs) ||
        (specType == Null) || (specType == ExObjdir))
    {
        while (*line) {
            /*
             * 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.
             */
            while (*cp && !isspace ((unsigned char)*cp)) {
                cp++;
            }
            savec = *cp;
            *cp = '\0';
            switch (specType) {
                case Suffixes:
                    Suff_AddSuffix(line, &mainNode);
                    break;
                case ExPath:
                    Lst_ForEach(paths, ParseAddDir, line);
                    break;
                case Includes:
                    Suff_AddInclude(line);
                    break;
                case Libs:
                    Suff_AddLib(line);
                    break;
                case Null:
                    Suff_SetNull(line);
                    break;
                case ExObjdir:
                    Main_SetObjdir(line);
                    break;
                default:
                    break;
            }
            *cp = savec;
            if (savec != '\0') {
                cp++;
            }
            while (*cp && isspace ((unsigned char)*cp)) {
                cp++;
            }
            line = cp;
        }
        if (paths) {
            Lst_Destroy(paths, NULL);
        }
        if (specType == ExPath)
            Dir_SetPATH();
    } else {
        while (*line) {
            /*
             * 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 (; *cp && !isspace ((unsigned char)*cp); cp++) {
                if ((*cp == LPAREN) && (cp > line) && (cp[-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 (*cp == LPAREN) {
                sources = Lst_Init(FALSE);
                if (Arch_ParseArchive(&line, sources, VAR_CMD) != SUCCESS) {
                    Parse_Error(PARSE_FATAL,
                                 "Error in source archive spec \"%s\"", line);
                    goto out;
                }

                while (!Lst_IsEmpty (sources)) {
                    gn = (GNode *)Lst_DeQueue(sources);
                    ParseDoSrc(tOp, gn->name);
                }
                Lst_Destroy(sources, NULL);
                cp = line;
            } else {
                if (*cp) {
                    *cp = '\0';
                    cp += 1;
                }

                ParseDoSrc(tOp, line);
            }
            while (*cp && isspace ((unsigned char)*cp)) {
                cp++;
            }
            line = cp;
        }
    }

    if (mainNode == NULL) {
        /*
         * 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.
         */
        Lst_ForEach(targets, ParseFindMain, NULL);
    }

out:
    if (curTargs)
            Lst_Destroy(curTargs, NULL);
}

/*-
 *---------------------------------------------------------------------
 * Parse_IsVar  --
 *      Return TRUE if the passed line is a variable assignment. A variable
 *      assignment consists of a single word followed by optional whitespace
 *      followed by either a += or an = operator.
 *      This function is used both by the Parse_File function and main when
 *      parsing the command-line arguments.
 *
 * Input:
 *      line            the line to check
 *
 * Results:
 *      TRUE if it is. FALSE if it ain't
 *
 * Side Effects:
 *      none
 *---------------------------------------------------------------------
 */
Boolean
Parse_IsVar(char *line)
{
    Boolean wasSpace = FALSE;   /* set TRUE if found a space */
    char ch;
    int level = 0;
#define ISEQOPERATOR(c) \
        (((c) == '+') || ((c) == ':') || ((c) == '?') || ((c) == '!'))

    /*
     * Skip to variable name
     */
    for (;(*line == ' ') || (*line == '\t'); line++)
        continue;

    /* Scan for one of the assignment operators outside a variable expansion */
    while ((ch = *line++) != 0) {
        if (ch == '(' || ch == '{') {
            level++;
            continue;
        }
        if (ch == ')' || ch == '}') {
            level--;
            continue;
        }
        if (level != 0)
            continue;
        while (ch == ' ' || ch == '\t') {
            ch = *line++;
            wasSpace = TRUE;
        }
#ifdef SUNSHCMD
        if (ch == ':' && strncmp(line, "sh", 2) == 0) {
            line += 2;
            continue;
        }
#endif
        if (ch == '=')
            return TRUE;
        if (*line == '=' && ISEQOPERATOR(ch))
            return TRUE;
        if (wasSpace)
            return FALSE;
    }

    return FALSE;
}

/*-
 *---------------------------------------------------------------------
 * Parse_DoVar  --
 *      Take the variable assignment in the passed line and do it in the
 *      global context.
 *
 *      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++ =".
 *
 * Input:
 *      line            a line guaranteed to be a variable assignment.
 *                      This reduces error checks
 *      ctxt            Context in which to do the assignment
 *
 * Results:
 *      none
 *
 * Side Effects:
 *      the variable structure of the given variable name is altered in the
 *      global context.
 *---------------------------------------------------------------------
 */
void
Parse_DoVar(char *line, GNode *ctxt)
{
    char           *cp; /* pointer into line */
    enum {
        VAR_SUBST, VAR_APPEND, VAR_SHELL, VAR_NORMAL
    }               type;       /* Type of assignment */
    char            *opc;       /* ptr to operator character to
                                 * null-terminate the variable name */
    Boolean        freeCp = FALSE; /* TRUE if cp needs to be freed,
                                    * i.e. if any variable expansion was
                                    * performed */
    int depth;

    /*
     * Skip to variable name
     */
    while ((*line == ' ') || (*line == '\t')) {
        line++;
    }

    /*
     * Skip to operator character, nulling out whitespace as we go
     * XXX Rather than counting () and {} we should look for $ and
     * then expand the variable.
     */
    for (depth = 0, cp = line + 1; depth != 0 || *cp != '='; cp++) {
        if (*cp == '(' || *cp == '{') {
            depth++;
            continue;
        }
        if (*cp == ')' || *cp == '}') {
            depth--;
            continue;
        }
        if (depth == 0 && isspace ((unsigned char)*cp)) {
            *cp = '\0';
        }
    }
    opc = cp-1;         /* operator is the previous character */
    *cp++ = '\0';       /* nuke the = */

    /*
     * Check operator type
     */
    switch (*opc) {
        case '+':
            type = VAR_APPEND;
            *opc = '\0';
            break;

        case '?':
            /*
             * If the variable already has a value, we don't do anything.
             */
            *opc = '\0';
            if (Var_Exists(line, ctxt)) {
                return;
            } else {
                type = VAR_NORMAL;
            }
            break;

        case ':':
            type = VAR_SUBST;
            *opc = '\0';
            break;

        case '!':
            type = VAR_SHELL;
            *opc = '\0';
            break;

        default:
#ifdef SUNSHCMD
            while (opc > line && *opc != ':')
                opc--;

            if (strncmp(opc, ":sh", 3) == 0) {
                type = VAR_SHELL;
                *opc = '\0';
                break;
            }
#endif
            type = VAR_NORMAL;
            break;
    }

    while (isspace ((unsigned char)*cp)) {
        cp++;
    }

    if (type == VAR_APPEND) {
        Var_Append(line, cp, ctxt);
    } else if (type == VAR_SUBST) {
        /*
         * Allow variables in the old value to be undefined, but leave their
         * invocation alone -- this is done by forcing oldVars to be false.
         * XXX: This can cause recursive variables, but that's not hard to do,
         * and this allows someone to do something like
         *
         *  CFLAGS = $(.INCLUDES)
         *  CFLAGS := -I.. $(CFLAGS)
         *
         * And not get an error.
         */
        Boolean   oldOldVars = oldVars;

        oldVars = FALSE;

        /*
         * make sure that we set the variable the first time to nothing
         * so that it gets substituted!
         */
        if (!Var_Exists(line, ctxt))
            Var_Set(line, "", ctxt, 0);

        cp = Var_Subst(NULL, cp, ctxt, FALSE);
        oldVars = oldOldVars;
        freeCp = TRUE;

        Var_Set(line, cp, ctxt, 0);
    } else if (type == VAR_SHELL) {
        char *res;
        const char *error;

        if (strchr(cp, '$') != NULL) {
            /*
             * There's a dollar sign in the command, so perform variable
             * expansion on the whole thing. The resulting string will need
             * freeing when we're done, so set freeCmd to TRUE.
             */
            cp = Var_Subst(NULL, cp, VAR_CMD, TRUE);
            freeCp = TRUE;
        }

        res = Cmd_Exec(cp, &error);
        Var_Set(line, res, ctxt, 0);
        free(res);

        if (error)
            Parse_Error(PARSE_WARNING, error, cp);
    } else {
        /*
         * Normal assignment -- just do it.
         */
        Var_Set(line, cp, ctxt, 0);
    }
    if (strcmp(line, MAKEOVERRIDES) == 0)
        Main_ExportMAKEFLAGS(FALSE);    /* re-export MAKEFLAGS */
    else if (strcmp(line, ".CURDIR") == 0) {
        /*
         * Somone is being (too?) clever...
         * Let's pretend they know what they are doing and
         * re-initialize the 'cur' Path.
         */
        Dir_InitCur(cp);
        Dir_SetPATH();
    } else if (strcmp(line, MAKE_JOB_PREFIX) == 0) {
        Job_SetPrefix();
    } else if (strcmp(line, MAKE_EXPORTED) == 0) {
        Var_Export(cp, 0);
    }
    if (freeCp)
        free(cp);
}


/*
 * ParseMaybeSubMake --
 *      Scan the command string to see if it a possible submake node
 * Input:
 *      cmd             the command to scan
 * Results:
 *      TRUE if the command is possibly a submake, FALSE if not.
 */
static Boolean
ParseMaybeSubMake(const char *cmd)
{
    size_t i;
    static struct {
        const char *name;
        size_t len;
    } vals[] = {
#define MKV(A)  {       A, sizeof(A) - 1        }
        MKV("${MAKE}"),
        MKV("${.MAKE}"),
        MKV("$(MAKE)"),
        MKV("$(.MAKE)"),
        MKV("make"),
    };
    for (i = 0; i < sizeof(vals)/sizeof(vals[0]); i++) {
        char *ptr;
        if ((ptr = strstr(cmd, vals[i].name)) == NULL)
            continue;
        if ((ptr == cmd || !isalnum((unsigned char)ptr[-1]))
            && !isalnum((unsigned char)ptr[vals[i].len]))
            return TRUE;
    }
    return FALSE;
}

/*-
 * ParseAddCmd  --
 *      Lst_ForEach function to add a command line to all targets
 *
 * Input:
 *      gnp             the node to which the command is to be added
 *      cmd             the command to add
 *
 * Results:
 *      Always 0
 *
 * Side Effects:
 *      A new element is added to the commands list of the node,
 *      and the node can be marked as a submake node if the command is
 *      determined to be that.
 */
static int
ParseAddCmd(void *gnp, void *cmd)
{
    GNode *gn = (GNode *)gnp;

    /* Add to last (ie current) cohort for :: targets */
    if ((gn->type & OP_DOUBLEDEP) && !Lst_IsEmpty (gn->cohorts))
        gn = (GNode *)Lst_Datum(Lst_Last(gn->cohorts));

    /* if target already supplied, ignore commands */
    if (!(gn->type & OP_HAS_COMMANDS)) {
        (void)Lst_AtEnd(gn->commands, cmd);
        if (ParseMaybeSubMake(cmd))
            gn->type |= OP_SUBMAKE;
        ParseMark(gn);
    } else {
#ifdef notyet
        /* XXX: We cannot do this until we fix the tree */
        (void)Lst_AtEnd(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, gn->lineno, PARSE_WARNING,
                            "using previous script for \"%s\" defined here",
                            gn->name);
#endif
    }
    return(0);
}

/*-
 *-----------------------------------------------------------------------
 * ParseHasCommands --
 *      Callback procedure for Parse_File when destroying the list of
 *      targets on the last dependency line. Marks a target as already
 *      having commands if it does, to keep from having shell commands
 *      on multiple dependency lines.
 *
 * Input:
 *      gnp             Node to examine
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      OP_HAS_COMMANDS may be set for the target.
 *
 *-----------------------------------------------------------------------
 */
static void
ParseHasCommands(void *gnp)
{
    GNode *gn = (GNode *)gnp;
    if (!Lst_IsEmpty(gn->commands)) {
        gn->type |= OP_HAS_COMMANDS;
    }
}

/*-
 *-----------------------------------------------------------------------
 * Parse_AddIncludeDir --
 *      Add a directory to the path searched for included makefiles
 *      bracketed by double-quotes. Used by functions in main.c
 *
 * Input:
 *      dir             The name of the directory to add
 *
 * Results:
 *      None.
 *
 * Side Effects:
 *      The directory is appended to the list.
 *
 *-----------------------------------------------------------------------
 */
void
Parse_AddIncludeDir(char *dir)
{
    (void)Dir_AddDir(parseIncPath, dir);
}

/*-
 *---------------------------------------------------------------------
 * ParseDoInclude  --
 *      Push to another file.
 *
 *      The input is the line minus the `.'. A file spec is a string
 *      enclosed in <> or "". The former is looked for only in sysIncPath.
 *      The latter in . and the directories specified by -I command line
 *      options
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      A structure is added to the includes Lst and readProc, lineno,
 *      fname and curFILE are altered for the new file
 *---------------------------------------------------------------------
 */

static void
Parse_include_file(char *file, Boolean isSystem, int silent)
{
    struct loadedfile *lf;
    char          *fullname;    /* full pathname of file */
    char          *newName;
    char          *prefEnd, *incdir;
    int           fd;
    int           i;

    /*
     * Now we know the file's name and its search path, we attempt to
     * find the durn thing. A return of NULL indicates the file don't
     * exist.
     */
    fullname = file[0] == '/' ? bmake_strdup(file) : NULL;

    if (fullname == NULL && !isSystem) {
        /*
         * Include files contained in double-quotes are first searched for
         * 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 beast.
         */

        incdir = bmake_strdup(curFile->fname);
        prefEnd = strrchr(incdir, '/');
        if (prefEnd != NULL) {
            *prefEnd = '\0';
            /* Now do lexical processing of leading "../" on the filename */
            for (i = 0; strncmp(file + i, "../", 3) == 0; i += 3) {
                prefEnd = strrchr(incdir + 1, '/');
                if (prefEnd == NULL || strcmp(prefEnd, "/..") == 0)
                    break;
                *prefEnd = '\0';
            }
            newName = str_concat(incdir, file + i, STR_ADDSLASH);
            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.
             */
            char *suff;
            Lst suffPath = NULL;

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

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

    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);

    ParseSetIncludedFile();
    /* Start reading from this file next */
    Parse_SetInput(fullname, 0, -1, loadedfile_nextbuf, lf);
    curFile->lf = lf;
}

static void
ParseDoInclude(char *line)
{
    char          endc;         /* the character which ends the file spec */
    char          *cp;          /* current position in file spec */
    int           silent = (*line != 'i') ? 1 : 0;
    char          *file = &line[7 + silent];

    /* Skip to delimiter character so we know where to look */
    while (*file == ' ' || *file == '\t')
        file++;

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

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

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

    if (*cp != endc) {
        Parse_Error(PARSE_FATAL,
                     "Unclosed %cinclude filename. '%c' expected",
                     '.', endc);
        return;
    }
    *cp = '\0';

    /*
     * Substitute for any variables in the file name before trying to
     * find the thing.
     */
    file = Var_Subst(NULL, file, VAR_CMD, FALSE);

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


/*-
 *---------------------------------------------------------------------
 * ParseSetIncludedFile  --
 *      Set the .INCLUDEDFROMFILE variable to the contents of .PARSEFILE
 *      and the .INCLUDEDFROMDIR variable to the contents of .PARSEDIR
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      The .INCLUDEDFROMFILE variable is overwritten by the contents
 *      of .PARSEFILE and the .INCLUDEDFROMDIR variable is overwriten
 *      by the contents of .PARSEDIR
 *---------------------------------------------------------------------
 */
static void
ParseSetIncludedFile(void)
{
    char *pf, *fp = NULL;
    char *pd, *dp = NULL;

    pf = Var_Value(".PARSEFILE", VAR_GLOBAL, &fp);
    Var_Set(".INCLUDEDFROMFILE", pf, VAR_GLOBAL, 0);
    pd = Var_Value(".PARSEDIR", VAR_GLOBAL, &dp);
    Var_Set(".INCLUDEDFROMDIR", pd, VAR_GLOBAL, 0);

    if (DEBUG(PARSE))
        fprintf(debug_file, "%s: ${.INCLUDEDFROMDIR} = `%s' "
            "${.INCLUDEDFROMFILE} = `%s'\n", __func__, pd, pf);

    if (fp)
        free(fp);
    if (dp)
        free(dp);
}
/*-
 *---------------------------------------------------------------------
 * ParseSetParseFile  --
 *      Set the .PARSEDIR and .PARSEFILE variables to the dirname and
 *      basename of the given filename
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      The .PARSEDIR and .PARSEFILE variables are overwritten by the
 *      dirname and basename of the given filename.
 *---------------------------------------------------------------------
 */
static void
ParseSetParseFile(const char *filename)
{
    char *slash, *dirname;
    const char *pd, *pf;
    int len;

    slash = strrchr(filename, '/');
    if (slash == NULL) {
        Var_Set(".PARSEDIR", pd = curdir, VAR_GLOBAL, 0);
        Var_Set(".PARSEFILE", pf = filename, VAR_GLOBAL, 0);
        dirname= NULL;
    } else {
        len = slash - filename;
        dirname = bmake_malloc(len + 1);
        memcpy(dirname, filename, len);
        dirname[len] = '\0';
        Var_Set(".PARSEDIR", pd = dirname, VAR_GLOBAL, 0);
        Var_Set(".PARSEFILE", pf = slash + 1, VAR_GLOBAL, 0);
    }
    if (DEBUG(PARSE))
        fprintf(debug_file, "%s: ${.PARSEDIR} = `%s' ${.PARSEFILE} = `%s'\n",
            __func__, pd, pf);
    free(dirname);
}

/*
 * Track the makefiles we read - so makefiles can
 * set dependencies on them.
 * Avoid adding anything more than once.
 */

static void
ParseTrackInput(const char *name)
{
    char *old;
    char *fp = NULL;
    size_t name_len = strlen(name);
    
    old = Var_Value(MAKE_MAKEFILES, VAR_GLOBAL, &fp);
    if (old) {
        /* does it contain name? */
        for (; old != NULL; old = strchr(old, ' ')) {
            if (*old == ' ')
                old++;
            if (memcmp(old, name, name_len) == 0
                    && (old[name_len] == 0 || old[name_len] == ' '))
                goto cleanup;
        }
    }
    Var_Append (MAKE_MAKEFILES, name, VAR_GLOBAL);
 cleanup:
    if (fp) {
        free(fp);
    }
}


/*-
 *---------------------------------------------------------------------
 * Parse_setInput  --
 *      Start Parsing from the given source
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      A structure is added to the includes Lst and readProc, lineno,
 *      fname and curFile are altered for the new file
 *---------------------------------------------------------------------
 */
void
Parse_SetInput(const char *name, int line, int fd,
        char *(*nextbuf)(void *, size_t *), void *arg)
{
    char *buf;
    size_t len;

    if (name == NULL)
        name = curFile->fname;
    else
        ParseTrackInput(name);

    if (DEBUG(PARSE))
        fprintf(debug_file, "%s: file %s, line %d, fd %d, nextbuf %p, arg %p\n",
            __func__, name, line, fd, nextbuf, arg);

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

    if (curFile != NULL)
        /* Save exiting file info */
        Lst_AtFront(includes, curFile);

    /* Allocate and fill in new structure */
    curFile = bmake_malloc(sizeof *curFile);

    /*
     * Once the previous state has been saved, we can get down to reading
     * the new file. We set up the name of the file to be the absolute
     * name of the include file so error messages refer to the right
     * place.
     */
    curFile->fname = bmake_strdup(name);
    curFile->lineno = line;
    curFile->first_lineno = line;
    curFile->nextbuf = nextbuf;
    curFile->nextbuf_arg = arg;
    curFile->lf = NULL;

    assert(nextbuf != NULL);

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

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

#ifdef SYSVINCLUDE
/*-
 *---------------------------------------------------------------------
 * ParseTraditionalInclude  --
 *      Push to another file.
 *
 *      The input is the current line. The file name(s) are
 *      following the "include".
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      A structure is added to the includes Lst and readProc, lineno,
 *      fname and curFILE are altered for the new file
 *---------------------------------------------------------------------
 */
static void
ParseTraditionalInclude(char *line)
{
    char          *cp;          /* current position in file spec */
    int            done = 0;
    int            silent = (line[0] != 'i') ? 1 : 0;
    char          *file = &line[silent + 7];
    char          *all_files;

    if (DEBUG(PARSE)) {
            fprintf(debug_file, "%s: %s\n", __func__, file);
    }

    /*
     * Skip over whitespace
     */
    while (isspace((unsigned char)*file))
        file++;

    /*
     * Substitute for any variables in the file name before trying to
     * find the thing.
     */
    all_files = Var_Subst(NULL, file, VAR_CMD, FALSE);

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

    for (file = all_files; !done; file = cp + 1) {
        /* Skip to end of line or next whitespace */
        for (cp = file; *cp && !isspace((unsigned char) *cp); cp++)
            continue;

        if (*cp)
            *cp = '\0';
        else
            done = 1;

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

#ifdef GMAKEEXPORT
/*-
 *---------------------------------------------------------------------
 * ParseGmakeExport  --
 *      Parse export <variable>=<value>
 *
 *      And set the environment with it.
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      None
 *---------------------------------------------------------------------
 */
static void
ParseGmakeExport(char *line)
{
    char          *variable = &line[6];
    char          *value;

    if (DEBUG(PARSE)) {
            fprintf(debug_file, "%s: %s\n", __func__, variable);
    }

    /*
     * Skip over whitespace
     */
    while (isspace((unsigned char)*variable))
        variable++;

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

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

    /*
     * Expand the value before putting it in the environment.
     */
    value = Var_Subst(NULL, value, VAR_CMD, FALSE);
    setenv(variable, value, 1);
}
#endif

/*-
 *---------------------------------------------------------------------
 * ParseEOF  --
 *      Called when EOF is reached in the current file. If we were reading
 *      an include file, the includes stack is popped and things set up
 *      to go back to reading the previous file at the previous location.
 *
 * Results:
 *      CONTINUE if there's more to do. DONE if not.
 *
 * Side Effects:
 *      The old curFILE, is closed. The includes list is shortened.
 *      lineno, curFILE, and fname are changed if CONTINUE is returned.
 *---------------------------------------------------------------------
 */
static int
ParseEOF(void)
{
    char *ptr;
    size_t len;

    assert(curFile->nextbuf != NULL);

    /* get next input buffer, if any */
    ptr = curFile->nextbuf(curFile->nextbuf_arg, &len);
    curFile->P_ptr = ptr;
    curFile->P_str = ptr;
    curFile->P_end = ptr + len;
    curFile->lineno = curFile->first_lineno;
    if (ptr != NULL) {
        /* Iterate again */
        return CONTINUE;
    }

    /* 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->P_str);
    free(curFile);

    curFile = Lst_DeQueue(includes);

    if (curFile == NULL) {
        /* We've run out of input */
        Var_Delete(".PARSEDIR", VAR_GLOBAL);
        Var_Delete(".PARSEFILE", VAR_GLOBAL);
        Var_Delete(".INCLUDEDFROMDIR", VAR_GLOBAL);
        Var_Delete(".INCLUDEDFROMFILE", VAR_GLOBAL);
        return DONE;
    }

    if (DEBUG(PARSE))
        fprintf(debug_file, "ParseEOF: returning to file %s, line %d\n",
            curFile->fname, curFile->lineno);

    /* Restore the PARSEDIR/PARSEFILE variables */
    ParseSetParseFile(curFile->fname);
    return (CONTINUE);
}

#define PARSE_RAW 1
#define PARSE_SKIP 2

static char *
ParseGetLine(int flags, int *length)
{
    IFile *cf = curFile;
    char *ptr;
    char ch;
    char *line;
    char *line_end;
    char *escaped;
    char *comment;
    char *tp;

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

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

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

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

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

        if (flags & PARSE_RAW) {
            /* Leave '\' (etc) in line buffer (eg 'for' lines) */
            *length = line_end - line;
            return line;
        }

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

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

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

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

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

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

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

        /* Escaped '\n' replace following whitespace with a single ' ' */
        while (ptr[0] == ' ' || ptr[0] == '\t')
            ptr++;
        ch = ' ';
    }

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

    *tp = 0;
    *length = tp - line;
    return line;
}

/*-
 *---------------------------------------------------------------------
 * ParseReadLine --
 *      Read an entire line from the input file. Called only by Parse_File.
 *
 * Results:
 *      A line w/o its newline
 *
 * Side Effects:
 *      Only those associated with reading a character
 *---------------------------------------------------------------------
 */
static char *
ParseReadLine(void)
{
    char          *line;        /* Result */
    int           lineLength;   /* Length of result */
    int           lineno;       /* Saved line # */
    int           rval;

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

/*-
 *-----------------------------------------------------------------------
 * ParseFinishLine --
 *      Handle the end of a dependency group.
 *
 * Results:
 *      Nothing.
 *
 * Side Effects:
 *      inLine set FALSE. 'targets' list destroyed.
 *
 *-----------------------------------------------------------------------
 */
static void
ParseFinishLine(void)
{
    if (inLine) {
        Lst_ForEach(targets, Suff_EndTransform, NULL);
        Lst_Destroy(targets, ParseHasCommands);
        targets = NULL;
        inLine = FALSE;
    }
}


/*-
 *---------------------------------------------------------------------
 * Parse_File --
 *      Parse a file into its component parts, incorporating it into the
 *      current dependency graph. This is the main function and controls
 *      almost every other function in this module
 *
 * Input:
 *      name            the name of the file being read
 *      fd              Open file to makefile to parse
 *
 * Results:
 *      None
 *
 * Side Effects:
 *      closes fd.
 *      Loads. Nodes are added to the list of all targets, nodes and links
 *      are added to the dependency graph. etc. etc. etc.
 *---------------------------------------------------------------------
 */
void
Parse_File(const char *name, int fd)
{
    char          *cp;          /* pointer into the line */
    char          *line;        /* the line we're working on */
    struct loadedfile *lf;

    lf = loadfile(name, fd);

    inLine = FALSE;
    fatals = 0;

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

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

    do {
        for (; (line = ParseReadLine()) != NULL; ) {
            if (DEBUG(PARSE))
                fprintf(debug_file, "ParseReadLine (%d): '%s'\n",
                        curFile->lineno, line);
            if (*line == '.') {
                /*
                 * Lines that begin with the special character may be
                 * include or undef directives.
                 * On the other hand they can be suffix rules (.c.o: ...)
                 * or just dependencies for filenames that start '.'.
                 */
                for (cp = line + 1; isspace((unsigned char)*cp); cp++) {
                    continue;
                }
                if (strncmp(cp, "include", 7) == 0 ||
                        ((cp[0] == 's' || cp[0] == '-') &&
                            strncmp(&cp[1], "include", 7) == 0)) {
                    ParseDoInclude(cp);
                    continue;
                }
                if (strncmp(cp, "undef", 5) == 0) {
                    char *cp2;
                    for (cp += 5; isspace((unsigned char) *cp); cp++)
                        continue;
                    for (cp2 = cp; !isspace((unsigned char) *cp2) &&
                                   (*cp2 != '\0'); cp2++)
                        continue;
                    *cp2 = '\0';
                    Var_Delete(cp, VAR_GLOBAL);
                    continue;
                } else if (strncmp(cp, "export", 6) == 0) {
                    for (cp += 6; isspace((unsigned char) *cp); cp++)
                        continue;
                    Var_Export(cp, 1);
                    continue;
                } else if (strncmp(cp, "unexport", 8) == 0) {
                    Var_UnExport(cp);
                    continue;
                } else if (strncmp(cp, "info", 4) == 0 ||
                           strncmp(cp, "error", 5) == 0 ||
                           strncmp(cp, "warning", 7) == 0) {
                    if (ParseMessage(cp))
                        continue;
                }                   
            }

            if (*line == '\t') {
                /*
                 * If a line starts with a tab, it can only hope to be
                 * a creation command.
                 */
                cp = line + 1;
              shellCommand:
                for (; isspace ((unsigned char)*cp); cp++) {
                    continue;
                }
                if (*cp) {
                    if (!inLine)
                        Parse_Error(PARSE_FATAL,
                                     "Unassociated shell command \"%s\"",
                                     cp);
                    /*
                     * So long as it's not a blank line and we're actually
                     * in a dependency spec, add the command to the list of
                     * commands of all targets in the dependency spec
                     */
                    if (targets) {
                        cp = bmake_strdup(cp);
                        Lst_ForEach(targets, ParseAddCmd, cp);
#ifdef CLEANUP
                        Lst_AtEnd(targCmds, cp);
#endif
                    }
                }
                continue;
            }

#ifdef SYSVINCLUDE
            if (((strncmp(line, "include", 7) == 0 &&
                    isspace((unsigned char) line[7])) ||
                        ((line[0] == 's' || line[0] == '-') &&
                            strncmp(&line[1], "include", 7) == 0 &&
                            isspace((unsigned char) line[8]))) &&
                    strchr(line, ':') == NULL) {
                /*
                 * It's an S3/S5-style "include".
                 */
                ParseTraditionalInclude(line);
                continue;
            }
#endif
#ifdef GMAKEEXPORT
            if (strncmp(line, "export", 6) == 0 &&
                isspace((unsigned char) line[6]) &&
                strchr(line, ':') == NULL) {
                /*
                 * It's a Gmake "export".
                 */
                ParseGmakeExport(line);
                continue;
            }
#endif
            if (Parse_IsVar(line)) {
                ParseFinishLine();
                Parse_DoVar(line, VAR_GLOBAL);
                continue;
            }

#ifndef POSIX
            /*
             * To make life easier on novices, if the line is indented we
             * first make sure the line has a dependency operator in it.
             * If it doesn't have an operator and we're in a dependency
             * line's script, we assume it's actually a shell command
             * and add it to the current list of targets.
             */
            cp = line;
            if (isspace((unsigned char) line[0])) {
                while ((*cp != '\0') && isspace((unsigned char) *cp))
                    cp++;
                while (*cp && (ParseIsEscaped(line, cp) ||
                        (*cp != ':') && (*cp != '!'))) {
                    cp++;
                }
                if (*cp == '\0') {
                    if (inLine) {
                        Parse_Error(PARSE_WARNING,
                                     "Shell command needs a leading tab");
                        goto shellCommand;
                    }
                }
            }
#endif
            ParseFinishLine();

            /*
             * For some reason - probably to make the parser impossible -
             * a ';' can be used to separate commands from dependencies.
             * Attempt to avoid ';' inside substitution patterns.
             */
            {
                int level = 0;

                for (cp = line; *cp != 0; cp++) {
                    if (*cp == '\\' && cp[1] != 0) {
                        cp++;
                        continue;
                    }
                    if (*cp == '$' &&
                        (cp[1] == '(' || cp[1] == '{')) {
                        level++;
                        continue;
                    }
                    if (level > 0) {
                        if (*cp == ')' || *cp == '}') {
                            level--;
                            continue;
                        }
                    } else if (*cp == ';') {
                        break;
                    }
                }
            }
            if (*cp != 0)
                /* Terminate the dependency list at the ';' */
                *cp++ = 0;
            else
                cp = NULL;

            /*
             * We now know it's a dependency line so it needs to have all
             * variables expanded before being parsed. Tell the variable
             * module to complain if some variable is undefined...
             */
            line = Var_Subst(NULL, line, VAR_CMD, TRUE);

            /*
             * Need a non-circular list for the target nodes
             */
            if (targets)
                Lst_Destroy(targets, NULL);

            targets = Lst_Init(FALSE);
            inLine = TRUE;

            ParseDoDependency(line);
            free(line);

            /* If there were commands after a ';', add them now */
            if (cp != NULL) {
                goto shellCommand;
            }
        }
        /*
         * Reached EOF, but it may be just EOF of an include file...
         */
    } while (ParseEOF() == CONTINUE);

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

/*-
 *---------------------------------------------------------------------
 * Parse_Init --
 *      initialize the parsing module
 *
 * Results:
 *      none
 *
 * Side Effects:
 *      the parseIncPath list is initialized...
 *---------------------------------------------------------------------
 */
void
Parse_Init(void)
{
    mainNode = NULL;
    parseIncPath = Lst_Init(FALSE);
    sysIncPath = Lst_Init(FALSE);
    defIncPath = Lst_Init(FALSE);
    includes = Lst_Init(FALSE);
#ifdef CLEANUP
    targCmds = Lst_Init(FALSE);
#endif
}

void
Parse_End(void)
{
#ifdef CLEANUP
    Lst_Destroy(targCmds, (FreeProc *)free);
    if (targets)
        Lst_Destroy(targets, NULL);
    Lst_Destroy(defIncPath, Dir_Destroy);
    Lst_Destroy(sysIncPath, Dir_Destroy);
    Lst_Destroy(parseIncPath, Dir_Destroy);
    Lst_Destroy(includes, NULL);        /* Should be empty now */
#endif
}


/*-
 *-----------------------------------------------------------------------
 * Parse_MainName --
 *      Return a Lst of the main target to create for main()'s sake. If
 *      no such target exists, we Punt with an obnoxious error message.
 *
 * Results:
 *      A Lst of the single node to create.
 *
 * Side Effects:
 *      None.
 *
 *-----------------------------------------------------------------------
 */
Lst
Parse_MainName(void)
{
    Lst           mainList;     /* result list */

    mainList = Lst_Init(FALSE);

    if (mainNode == NULL) {
        Punt("no target to make.");
        /*NOTREACHED*/
    } else if (mainNode->type & OP_DOUBLEDEP) {
        (void)Lst_AtEnd(mainList, mainNode);
        Lst_Concat(mainList, mainNode->cohorts, LST_CONCNEW);
    }
    else
        (void)Lst_AtEnd(mainList, mainNode);
    Var_Append(".TARGETS", mainNode->name, VAR_GLOBAL);
    return (mainList);
}

/*-
 *-----------------------------------------------------------------------
 * ParseMark --
 *      Add the filename and lineno to the GNode so that we remember
 *      where it was first defined.
 *
 * Side Effects:
 *      None.
 *
 *-----------------------------------------------------------------------
 */
static void
ParseMark(GNode *gn)
{
    gn->fname = curFile->fname;
    gn->lineno = curFile->lineno;
}