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Revision 1.41, Thu May 3 13:41:11 2001 UTC (23 years, 1 month ago) by espie
Branch: MAIN
Changes since 1.40: +620 -822 lines

Synch with my current work.
Numerous changes:
- generate can build several tables
- style cleanup
- statistics code
- use variable names throughout (struct Name)
- recursive variables everywhere
- faster parser (pass buffer along instead of allocating multiple copies)
- correct parser. Handles comments everywhere, and ; correctly
- more string intervals
- simplified dir.c, less recursion.
- extended for loops
- sinclude()
- finished removing extra junk from Lst_*
- handles ${@D} and friends in a simpler way
- cleaned up and modular VarModifiers handling.
- recognizes some gnu Makefile usages and errors out about them.

Additionally, some extra functionality is defined by FEATURES. The set of
functionalities is currently hardcoded to OpenBSD defaults, but this may
include support for some NetBSD extensions, like ODE modifiers.

Backed by miod@ and millert@, who finally got sick of my endless patches...

/*	$OpenPackages$ */
/*	$OpenBSD: suff.c,v 1.41 2001/05/03 13:41:11 espie Exp $ */
/*	$NetBSD: suff.c,v 1.13 1996/11/06 17:59:25 christos Exp $	*/

/*
 * Copyright (c) 1988, 1989, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 * 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.
 */

/*-
 * suff.c --
 *	Functions to maintain suffix lists and find implicit dependents
 *	using suffix transformation rules
 *
 * Interface:
 *	Suff_Init		Initialize all things to do with suffixes.
 *
 *	Suff_End		Cleanup the module
 *
 *	Suff_DoPaths		This function is used to make life easier
 *				when searching for a file according to its
 *				suffix. It takes the global search path,
 *				as defined using the .PATH: target, and appends
 *				its directories to the path of each of the
 *				defined suffixes, as specified using
 *				.PATH<suffix>: targets. In addition, all
 *				directories given for suffixes labeled as
 *				include files or libraries, using the .INCLUDES
 *				or .LIBS targets, are played with using
 *				Dir_MakeFlags to create the .INCLUDES and
 *				.LIBS global variables.
 *
 *	Suff_ClearSuffixes	Clear out all the suffixes and defined
 *				transformations.
 *
 *	Suff_IsTransform	Return TRUE if the passed string is the lhs
 *				of a transformation rule.
 *
 *	Suff_AddSuffix		Add the passed string as another known suffix.
 *
 *	Suff_GetPath		Return the search path for the given suffix.
 *
 *	Suff_AddInclude 	Mark the given suffix as denoting an include
 *				file.
 *
 *	Suff_AddLib		Mark the given suffix as denoting a library.
 *
 *	Suff_AddTransform	Add another transformation to the suffix
 *				graph. Returns	GNode suitable for framing, I
 *				mean, tacking commands, attributes, etc. on.
 *
 *	Suff_SetNull		Define the suffix to consider the suffix of
 *				any file that doesn't have a known one.
 *
 *	Suff_FindDeps		Find implicit sources for and the location of
 *				a target based on its suffix. Returns the
 *				bottom-most node added to the graph or NULL
 *				if the target had no implicit sources.
 */

#include	  <stddef.h>
#include	  <stdio.h>
#include	  "make.h"
#include	  "ohash.h"
#include	  "dir.h"

#ifndef lint
#if 0
static char sccsid[] = "@(#)suff.c	8.4 (Berkeley) 3/21/94";
#else
UNUSED
static char rcsid[] = "$OpenBSD: suff.c,v 1.41 2001/05/03 13:41:11 espie Exp $";
#endif
#endif /* not lint */

static LIST	 sufflist;	/* Lst of suffixes */
#ifdef CLEANUP
static LIST	 suffClean;	/* Lst of suffixes to be cleaned */
#endif
static LIST	 srclist;	/* Lst of sources */
static LIST	 transforms;	/* Lst of transformation rules */

static int	  sNum = 0;	/* Counter for assigning suffix numbers */

/*
 * Structure describing an individual suffix.
 */
typedef struct Suff_ {
    char	 *name; 	/* The suffix itself */
    int 	 nameLen;	/* Length of the suffix */
    short	 flags; 	/* Type of suffix */
#define SUFF_INCLUDE	  0x01	    /* One which is #include'd */
#define SUFF_LIBRARY	  0x02	    /* One which contains a library */
#define SUFF_NULL	  0x04	    /* The empty suffix */
    LIST	 searchPath;	/* The path along which files of this suffix
				 * may be found */
    int 	 sNum;		/* The suffix number */
    LIST	 parents;	/* Suffixes we have a transformation to */
    LIST	 children;	/* Suffixes we have a transformation from */
    LIST	 ref;		/* List of lists this suffix is referenced */
} Suff;

/*
 * Structure used in the search for implied sources.
 */
typedef struct Src_ {
    char	    *file;	/* The file to look for */
    char	    *pref;	/* Prefix from which file was formed */
    Suff	    *suff;	/* The suffix on the file */
    struct Src_     *parent;	/* The Src for which this is a source */
    GNode	    *node;	/* The node describing the file */
    int 	    children;	/* Count of existing children (so we don't free
				 * this thing too early or never nuke it) */
#ifdef DEBUG_SRC
    LIST	    cp; 	/* Debug; children list */
#endif
} Src;

/*
 * A structure for passing more than one argument to the Lst-library-invoked
 * function...
 */
typedef struct {
    Lst 	   l;
    Src 	   *s;
} LstSrc;

static Suff	    *suffNull;	/* The NULL suffix for this run */
static Suff	    *emptySuff; /* The empty suffix required for POSIX
				 * single-suffix transformation rules */


static char *SuffStrIsPrefix(const char *, const char *);
static char *SuffSuffIsSuffix(Suff *, const char *);
static int SuffSuffIsSuffixP(void *, const void *);
static int SuffSuffHasNameP(void *, const void *);
static int SuffSuffIsPrefix(void *, const void *);
static int SuffGNHasNameP(void *, const void *);
static void SuffUnRef(Lst, Suff *);
#ifdef CLEANUP
static void SuffFree(void *);
#endif
static void SuffInsert(Lst, Suff *);
static Boolean SuffParseTransform(const char *, Suff **, Suff **);
static void SuffRebuildGraph(void *, void *);
static void SuffAddSrc(void *, void *);
static int SuffRemoveSrc(Lst);
static void SuffAddLevel(Lst, Src *);
static Src *SuffFindThem(Lst, Lst);
static Src *SuffFindCmds(Src *, Lst);
static void SuffExpandChildren(void *, void *);
static void SuffExpandVarChildren(LstNode, GNode *, GNode *);
static void SuffExpandWildChildren(LstNode, GNode *, GNode *);
static Boolean SuffApplyTransform(GNode *, GNode *, Suff *, Suff *);
static void SuffFindDeps(GNode *, Lst);
static void SuffFindArchiveDeps(GNode *, Lst);
static void SuffFindNormalDeps(GNode *, Lst);
static void SuffPrintName(void *);
static void SuffPrintSuff(void *);
static void SuffPrintTrans(void *);

	/*************** Lst Predicates ****************/
/*-
 *-----------------------------------------------------------------------
 * SuffStrIsPrefix  --
 *	See if pref is a prefix of str.
 *
 * Results:
 *	NULL if it ain't, pointer to character in str after prefix if so
 *-----------------------------------------------------------------------
 */
static char    *
SuffStrIsPrefix(pref, str)
    const char	*pref;	/* possible prefix */
    const char	*str;	/* string to check */
{
    while (*str && *pref == *str) {
	pref++;
	str++;
    }

    return *pref ? NULL : (char *)str;
}

/*-
 *-----------------------------------------------------------------------
 * SuffSuffIsSuffix  --
 *	See if suff is a suffix of str. str should point to the end of the
 *	string to check.
 *
 * Results:
 *	NULL if it ain't, pointer to first character of suffix in str if
 *	it is.
 *-----------------------------------------------------------------------
 */
static char *
SuffSuffIsSuffix(s, str)
    Suff	   *s;		/* possible suffix */
    const char	   *str;	/* string to examine */
{
    const char	   *p1; 	/* Pointer into suffix name */
    const char	   *p2; 	/* Pointer into string being examined */

    p1 = s->name + s->nameLen;
    p2 = str;

    while (p1 != s->name) {
	p1--;
	p2--;
	if (*p1 != *p2)
		return NULL;
    }

    return (char *)p2;
}

/*-
 *-----------------------------------------------------------------------
 * SuffSuffIsSuffixP --
 *	Predicate form of SuffSuffIsSuffix. Passed as the callback function
 *	to Lst_Find.
 *
 * Results:
 *	0 if the suffix is the one desired, non-zero if not.
 *-----------------------------------------------------------------------
 */
static int
SuffSuffIsSuffixP(s, str)
    void	*s;
    const void	*str;
{
    return !SuffSuffIsSuffix((Suff *)s, (const char *)str);
}

/*-
 *-----------------------------------------------------------------------
 * SuffSuffHasNameP --
 *	Callback procedure for finding a suffix based on its name. Used by
 *	Suff_GetPath.
 *
 * Results:
 *	0 if the suffix is of the given name. non-zero otherwise.
 *-----------------------------------------------------------------------
 */
static int
SuffSuffHasNameP(s, sname)
    void	*s;		    /* Suffix to check */
    const void	*sname; 	    /* Desired name */
{
    return strcmp((const char *)sname, ((Suff *)s)->name);
}

/*-
 *-----------------------------------------------------------------------
 * SuffSuffIsPrefix  --
 *	See if the suffix described by s is a prefix of the string. Care
 *	must be taken when using this to search for transformations and
 *	what-not, since there could well be two suffixes, one of which
 *	is a prefix of the other...
 *
 * Results:
 *	0 if s is a prefix of str. non-zero otherwise
 *-----------------------------------------------------------------------
 */
static int
SuffSuffIsPrefix(s, str)
    void	*s;		/* suffix to compare */
    const void	*str;	/* string to examine */
{
    return SuffStrIsPrefix(((Suff *)s)->name, (const char *)str) == NULL ? 1 : 0;
}

/*-
 *-----------------------------------------------------------------------
 * SuffGNHasNameP  --
 *	See if the graph node has the desired name
 *
 * Results:
 *	0 if it does. non-zero if it doesn't
 *-----------------------------------------------------------------------
 */
static int
SuffGNHasNameP(gn, name)
    void	*gn;		/* current node we're looking at */
    const void	*name;		/* name we're looking for */
{
    return strcmp((const char *)name, ((GNode *)gn)->name);
}

	    /*********** Maintenance Functions ************/

static void
SuffUnRef(l, sp)
    Lst 	l;
    Suff	*sp;
{
    LstNode ln = Lst_Member(l, sp);
    if (ln != NULL)
	Lst_Remove(l, ln);
}

#ifdef CLEANUP
/*-
 *-----------------------------------------------------------------------
 * SuffFree  --
 *	Free up all memory associated with the given suffix structure.
 *
 * Side Effects:
 *	the suffix entry is detroyed
 *-----------------------------------------------------------------------
 */
static void
SuffFree(sp)
    void	*sp;
{
    Suff	*s = (Suff *)sp;

    if (s == suffNull)
	suffNull = NULL;

    if (s == emptySuff)
	emptySuff = NULL;

    Lst_Destroy(&s->ref, NOFREE);
    Lst_Destroy(&s->children, NOFREE);
    Lst_Destroy(&s->parents, NOFREE);
    Lst_Destroy(&s->searchPath, Dir_Destroy);

    free(s->name);
    free(s);
}
#endif


/*-
 *-----------------------------------------------------------------------
 * SuffInsert  --
 *	Insert the suffix into the list keeping the list ordered by suffix
 *	numbers.
 *
 * Side Effects:
 *	The reference count of the suffix is incremented
 *-----------------------------------------------------------------------
 */
static void
SuffInsert(l, s)
    Lst 	  l;		/* the list where in s should be inserted */
    Suff	  *s;		/* the suffix to insert */
{
    LstNode	  ln;		/* current element in l we're examining */
    Suff	  *s2 = NULL;	/* the suffix descriptor in this element */

    for (ln = Lst_First(l); ln != NULL; ln = Lst_Adv(ln)) {
	s2 = (Suff *)Lst_Datum(ln);
	if (s2->sNum >= s->sNum)
	    break;
    }

    if (DEBUG(SUFF)) {
	printf("inserting %s(%d)...", s->name, s->sNum);
    }
    if (ln == NULL) {
	if (DEBUG(SUFF)) {
	    printf("at end of list\n");
	}
	Lst_AtEnd(l, s);
	Lst_AtEnd(&s->ref, l);
    } else if (s2->sNum != s->sNum) {
	if (DEBUG(SUFF)) {
	    printf("before %s(%d)\n", s2->name, s2->sNum);
	}
	Lst_Insert(l, ln, s);
	Lst_AtEnd(&s->ref, l);
    } else if (DEBUG(SUFF)) {
	printf("already there\n");
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_ClearSuffixes --
 *	This is gross. Nuke the list of suffixes but keep all transformation
 *	rules around. The transformation graph is destroyed in this process,
 *	but we leave the list of rules so when a new graph is formed the rules
 *	will remain.
 *	This function is called from the parse module when a
 *	.SUFFIXES:\n line is encountered.
 *
 * Side Effects:
 *	the sufflist and its graph nodes are destroyed
 *-----------------------------------------------------------------------
 */
void
Suff_ClearSuffixes()
{
#ifdef CLEANUP
    Lst_ConcatDestroy(&suffClean, &sufflist);
#endif
    Lst_Init(&sufflist);
    sNum = 0;
    suffNull = emptySuff;
}

/*-
 *-----------------------------------------------------------------------
 * SuffParseTransform --
 *	Parse a transformation string to find its two component suffixes.
 *
 * Results:
 *	TRUE if the string is a valid transformation and FALSE otherwise.
 *
 * Side Effects:
 *	The passed pointers are overwritten.
 *-----------------------------------------------------------------------
 */
static Boolean
SuffParseTransform(str, srcPtr, targPtr)
    const char		*str;		/* String being parsed */
    Suff		**srcPtr;	/* Place to store source of trans. */
    Suff		**targPtr;	/* Place to store target of trans. */
{
    LstNode		srcLn;	    /* element in suffix list of trans source*/
    Suff		*src;	    /* Source of transformation */
    LstNode		targLn;     /* element in suffix list of trans target*/
    const char		*str2;	    /* Extra pointer (maybe target suffix) */
    LstNode		singleLn;   /* element in suffix list of any suffix
				     * that exactly matches str */
    Suff		*single = NULL;/* Source of possible transformation to
				     * null suffix */

    srcLn = NULL;
    singleLn = NULL;

    /*
     * Loop looking first for a suffix that matches the start of the
     * string and then for one that exactly matches the rest of it. If
     * we can find two that meet these criteria, we've successfully
     * parsed the string.
     */
    for (;;) {
	if (srcLn == NULL)
	    srcLn = Lst_FindConst(&sufflist, SuffSuffIsPrefix, str);
	else
	    srcLn = Lst_FindFromConst(Lst_Succ(srcLn), SuffSuffIsPrefix, str);
	if (srcLn == NULL) {
	    /*
	     * Ran out of source suffixes -- no such rule
	     */
	    if (singleLn != NULL) {
		/*
		 * Not so fast Mr. Smith! There was a suffix that encompassed
		 * the entire string, so we assume it was a transformation
		 * to the null suffix (thank you POSIX). We still prefer to
		 * find a double rule over a singleton, hence we leave this
		 * check until the end.
		 *
		 * XXX: Use emptySuff over suffNull?
		 */
		*srcPtr = single;
		*targPtr = suffNull;
		return TRUE;
	    }
	    return FALSE;
	}
	src = (Suff *)Lst_Datum(srcLn);
	str2 = str + src->nameLen;
	if (*str2 == '\0') {
	    single = src;
	    singleLn = srcLn;
	} else {
	    targLn = Lst_FindConst(&sufflist, SuffSuffHasNameP, str2);
	    if (targLn != NULL) {
		*srcPtr = src;
		*targPtr = (Suff *)Lst_Datum(targLn);
		return TRUE;
	    }
	}
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_IsTransform  --
 *	Return TRUE if the given string is a transformation rule
 *
 * Results:
 *	TRUE if the string is a concatenation of two known suffixes.
 *	FALSE otherwise
 *-----------------------------------------------------------------------
 */
Boolean
Suff_IsTransform(str)
    const char	  *str; 	/* string to check */
{
    Suff	  *src, *targ;

    return SuffParseTransform(str, &src, &targ);
}

/*-
 *-----------------------------------------------------------------------
 * Suff_AddTransform --
 *	Add the transformation rule described by the line to the
 *	list of rules and place the transformation itself in the graph
 *
 * Results:
 *	The node created for the transformation in the transforms list
 *
 * Side Effects:
 *	The node is placed on the end of the transforms Lst and links are
 *	made between the two suffixes mentioned in the target name
 *-----------------------------------------------------------------------
 */
GNode *
Suff_AddTransform(line)
    const char	  *line;	/* name of transformation to add */
{
    GNode	  *gn;		/* GNode of transformation rule */
    Suff	  *s,		/* source suffix */
		  *t;		/* target suffix */
    LstNode	  ln;		/* Node for existing transformation */

    ln = Lst_FindConst(&transforms, SuffGNHasNameP, line);
    if (ln == NULL) {
	/*
	 * Make a new graph node for the transformation. It will be filled in
	 * by the Parse module.
	 */
	gn = Targ_NewGN(line, NULL);
	Lst_AtEnd(&transforms, gn);
    } else {
	/*
	 * New specification for transformation rule. Just nuke the old list
	 * of commands so they can be filled in again... We don't actually
	 * free the commands themselves, because a given command can be
	 * attached to several different transformations.
	 */
	gn = (GNode *)Lst_Datum(ln);
	Lst_Destroy(&gn->commands, NOFREE);
	Lst_Init(&gn->commands);
	Lst_Destroy(&gn->children, NOFREE);
	Lst_Init(&gn->children);
    }

    gn->type = OP_TRANSFORM;

    (void)SuffParseTransform(line, &s, &t);

    /*
     * link the two together in the proper relationship and order
     */
    if (DEBUG(SUFF)) {
	printf("defining transformation from `%s' to `%s'\n",
		s->name, t->name);
    }
    SuffInsert(&t->children, s);
    SuffInsert(&s->parents, t);

    return gn;
}

/*-
 *-----------------------------------------------------------------------
 * Suff_EndTransform --
 *	Handle the finish of a transformation definition, removing the
 *	transformation from the graph if it has neither commands nor
 *	sources. This is a callback procedure for the Parse module via
 *	Lst_ForEach
 *
 * Side Effects:
 *	If the node has no commands or children, the children and parents
 *	lists of the affected suffices are altered.
 *-----------------------------------------------------------------------
 */
void
Suff_EndTransform(gnp)
    void *gnp;		/* Node for transformation */
{
    GNode *gn = (GNode *)gnp;

    if ((gn->type & OP_TRANSFORM) && Lst_IsEmpty(&gn->commands) &&
	Lst_IsEmpty(&gn->children))
    {
	Suff	*s, *t;

	(void)SuffParseTransform(gn->name, &s, &t);

	if (DEBUG(SUFF)) {
	    printf("deleting transformation from `%s' to `%s'\n",
		    s->name, t->name);
	}

	/*
	 * Remove the source from the target's children list.
	 *
	 * We'll be called twice when the next target is seen, but .c and .o
	 * are only linked once...
	 */
	SuffUnRef(&t->children, s);

	/*
	 * Remove the target from the source's parents list
	 */
	if (s != NULL)
	    SuffUnRef(&s->parents, t);
    } else if ((gn->type & OP_TRANSFORM) && DEBUG(SUFF)) {
	printf("transformation %s complete\n", gn->name);
    }
}

/*-
 *-----------------------------------------------------------------------
 * SuffRebuildGraph --
 *	Called from Suff_AddSuffix via Lst_ForEach to search through the
 *	list of existing transformation rules and rebuild the transformation
 *	graph when it has been destroyed by Suff_ClearSuffixes. If the
 *	given rule is a transformation involving this suffix and another,
 *	existing suffix, the proper relationship is established between
 *	the two.
 *
 * Side Effects:
 *	The appropriate links will be made between this suffix and
 *	others if transformation rules exist for it.
 *-----------------------------------------------------------------------
 */
static void
SuffRebuildGraph(transformp, sp)
    void	*transformp;	/* Transformation to test */
    void	*sp;		/* Suffix to rebuild */
{
    GNode	*transform = (GNode *)transformp;
    Suff	*s = (Suff *)sp;
    char	*cp;
    LstNode	ln;
    Suff	*s2;

    /* First see if it is a transformation from this suffix.  */
    cp = SuffStrIsPrefix(s->name, transform->name);
    if (cp != NULL) {
	ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, cp);
	if (ln != NULL) {
	    /* Found target. Link in and return, since it can't be anything
	     * else.  */
	    s2 = (Suff *)Lst_Datum(ln);
	    SuffInsert(&s2->children, s);
	    SuffInsert(&s->parents, s2);
	    return;
	}
    }

    /* Not from, maybe to?  */
    cp = SuffSuffIsSuffix(s, transform->name + strlen(transform->name));
    if (cp != NULL) {
	/* Null-terminate the source suffix in order to find it.  */
	*cp = '\0';
	ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, transform->name);
	/* Replace the start of the target suffix.  */
	*cp = s->name[0];
	if (ln != NULL) {
	    /* Found it -- establish the proper relationship.  */
	    s2 = (Suff *)Lst_Datum(ln);
	    SuffInsert(&s->children, s2);
	    SuffInsert(&s2->parents, s);
	}
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_AddSuffix --
 *	Add the suffix in string to the end of the list of known suffixes.
 *	Should we restructure the suffix graph? Make doesn't...
 *
 * Side Effects:
 *	A GNode is created for the suffix and a Suff structure is created and
 *	added to the suffixes list unless the suffix was already known.
 *-----------------------------------------------------------------------
 */
void
Suff_AddSuffix(str)
    char	  *str;     /* the name of the suffix to add */
{
    Suff	  *s;	    /* new suffix descriptor */
    LstNode	  ln;

    ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, str);
    if (ln == NULL) {
	s = emalloc(sizeof(Suff));

	s->name =	estrdup(str);
	s->nameLen =	strlen(s->name);
	Lst_Init(&s->searchPath);
	Lst_Init(&s->children);
	Lst_Init(&s->parents);
	Lst_Init(&s->ref);
	s->sNum =	sNum++;
	s->flags =	0;

	Lst_AtEnd(&sufflist, s);
	/*
	 * Look for any existing transformations from or to this suffix.
	 * XXX: Only do this after a Suff_ClearSuffixes?
	 */
	Lst_ForEach(&transforms, SuffRebuildGraph, s);
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_GetPath --
 *	Return the search path for the given suffix, if it's defined.
 *
 * Results:
 *	The searchPath for the desired suffix or NULL if the suffix isn't
 *	defined.
 *-----------------------------------------------------------------------
 */
Lst
Suff_GetPath(sname)
    char	  *sname;
{
    LstNode	  ln;
    Suff	  *s;

    ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, sname);
    if (ln == NULL) {
	return NULL;
    } else {
	s = (Suff *)Lst_Datum(ln);
	return &s->searchPath;
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_DoPaths --
 *	Extend the search paths for all suffixes to include the default
 *	search path.
 *
 * Side Effects:
 *	The searchPath field of all the suffixes is extended by the
 *	directories in dirSearchPath. If paths were specified for the
 *	".h" suffix, the directories are stuffed into a global variable
 *	called ".INCLUDES" with each directory preceeded by a -I. The same
 *	is done for the ".a" suffix, except the variable is called
 *	".LIBS" and the flag is -L.
 *-----------------------------------------------------------------------
 */
void
Suff_DoPaths()
{
    Suff		*s;
    LstNode		ln;
    char		*ptr;
    LIST		inIncludes; /* Cumulative .INCLUDES path */
    LIST		inLibs;     /* Cumulative .LIBS path */

    Lst_Init(&inIncludes);
    Lst_Init(&inLibs);

    for (ln = Lst_First(&sufflist); ln != NULL; ln = Lst_Adv(ln)) {
	s = (Suff *)Lst_Datum(ln);
	if (!Lst_IsEmpty(&s->searchPath)) {
#ifdef INCLUDES
	    if (s->flags & SUFF_INCLUDE) {
		Dir_Concat(&inIncludes, &s->searchPath);
	    }
#endif /* INCLUDES */
#ifdef LIBRARIES
	    if (s->flags & SUFF_LIBRARY) {
		Dir_Concat(&inLibs, &s->searchPath);
	    }
#endif /* LIBRARIES */
	    Dir_Concat(&s->searchPath, &dirSearchPath);
	} else {
	    Lst_Destroy(&s->searchPath, Dir_Destroy);
	    Lst_Clone(&s->searchPath, &dirSearchPath, Dir_CopyDir);
	}
    }

    Var_Set(".INCLUDES", ptr = Dir_MakeFlags("-I", &inIncludes), VAR_GLOBAL);
    free(ptr);
    Var_Set(".LIBS", ptr = Dir_MakeFlags("-L", &inLibs), VAR_GLOBAL);
    free(ptr);

    Lst_Destroy(&inIncludes, Dir_Destroy);
    Lst_Destroy(&inLibs, Dir_Destroy);
}

/*-
 *-----------------------------------------------------------------------
 * Suff_AddInclude --
 *	Add the given suffix as a type of file which gets included.
 *	Called from the parse module when a .INCLUDES line is parsed.
 *	The suffix must have already been defined.
 *
 * Side Effects:
 *	The SUFF_INCLUDE bit is set in the suffix's flags field
 *-----------------------------------------------------------------------
 */
void
Suff_AddInclude(sname)
    char	  *sname;     /* Name of suffix to mark */
{
    LstNode	  ln;
    Suff	  *s;

    ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, sname);
    if (ln != NULL) {
	s = (Suff *)Lst_Datum(ln);
	s->flags |= SUFF_INCLUDE;
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_AddLib --
 *	Add the given suffix as a type of file which is a library.
 *	Called from the parse module when parsing a .LIBS line. The
 *	suffix must have been defined via .SUFFIXES before this is
 *	called.
 *
 * Side Effects:
 *	The SUFF_LIBRARY bit is set in the suffix's flags field
 *-----------------------------------------------------------------------
 */
void
Suff_AddLib(sname)
    char	  *sname;     /* Name of suffix to mark */
{
    LstNode	  ln;
    Suff	  *s;

    ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, sname);
    if (ln != NULL) {
	s = (Suff *)Lst_Datum(ln);
	s->flags |= SUFF_LIBRARY;
    }
}

	  /********** Implicit Source Search Functions *********/

/*-
 *-----------------------------------------------------------------------
 * SuffAddSrc  --
 *	Add a suffix as a Src structure to the given list with its parent
 *	being the given Src structure. If the suffix is the null suffix,
 *	the prefix is used unaltered as the file name in the Src structure.
 *
 * Side Effects:
 *	A Src structure is created and tacked onto the end of the list
 *-----------------------------------------------------------------------
 */
static void
SuffAddSrc(sp, lsp)
    void *sp;	    /* suffix for which to create a Src structure */
    void *lsp;	    /* list and parent for the new Src */
{
    Suff	*s = (Suff *)sp;
    LstSrc	*ls = (LstSrc *)lsp;
    Src 	*s2;	    /* new Src structure */
    Src 	*targ;	    /* Target structure */

    targ = ls->s;

    if ((s->flags & SUFF_NULL) && *s->name != '\0') {
	/*
	 * If the suffix has been marked as the NULL suffix, also create a Src
	 * structure for a file with no suffix attached. Two birds, and all
	 * that...
	 */
	s2 = emalloc(sizeof(Src));
	s2->file =	estrdup(targ->pref);
	s2->pref =	targ->pref;
	s2->parent =	targ;
	s2->node =	NULL;
	s2->suff =	s;
	s2->children =	0;
	targ->children += 1;
	Lst_AtEnd(ls->l, s2);
#ifdef DEBUG_SRC
	Lst_Init(&s2->cp);
	Lst_AtEnd(&targ->cp, s2);
	printf("1 add %x %x to %x:", targ, s2, ls->l);
	Lst_Every(ls->l, PrintAddr);
	printf("\n");
#endif
    }
    s2 = emalloc(sizeof(Src));
    s2->file =	    str_concat(targ->pref, s->name, 0);
    s2->pref =	    targ->pref;
    s2->parent =    targ;
    s2->node =	    NULL;
    s2->suff =	    s;
    s2->children =  0;
    targ->children += 1;
    Lst_AtEnd(ls->l, s2);
#ifdef DEBUG_SRC
    Lst_Init(&s2->cp);
    Lst_AtEnd(&targ->cp, s2);
    printf("2 add %x %x to %x:", targ, s2, ls->l);
    Lst_Every(ls->l, PrintAddr);
    printf("\n");
#endif

}

/*-
 *-----------------------------------------------------------------------
 * SuffAddLevel  --
 *	Add all the children of targ as Src structures to the given list
 *
 * Side Effects:
 *	Lots of structures are created and added to the list
 *-----------------------------------------------------------------------
 */
static void
SuffAddLevel(l, targ)
    Lst 	   l;		/* list to which to add the new level */
    Src 	   *targ;	/* Src structure to use as the parent */
{
    LstSrc	   ls;

    ls.s = targ;
    ls.l = l;

    Lst_ForEach(&targ->suff->children, SuffAddSrc, &ls);
}

/*-
 *----------------------------------------------------------------------
 * SuffRemoveSrc --
 *	Free all src structures in list that don't have a reference count
 *
 * Results:
 *	Ture if an src was removed
 *
 * Side Effects:
 *	The memory is free'd.
 *----------------------------------------------------------------------
 */
static int
SuffRemoveSrc(l)
    Lst l;
{
    LstNode ln;
    Src *s;
    int t = 0;

#ifdef DEBUG_SRC
    printf("cleaning %lx: ", (unsigned long)l);
    Lst_Every(l, PrintAddr);
    printf("\n");
#endif


    for (ln = Lst_First(l); ln != NULL; ln = Lst_Adv(ln)) {
	s = (Src *)Lst_Datum(ln);
	if (s->children == 0) {
	    free(s->file);
	    if (!s->parent)
		free(s->pref);
	    else {
#ifdef DEBUG_SRC
		LstNode ln2 = Lst_Member(&s->parent->cp, s);
		if (ln2 != NULL)
		    Lst_Remove(&s->parent->cp, ln2);
#endif
		--s->parent->children;
	    }
#ifdef DEBUG_SRC
	    printf("free: [l=%x] p=%x %d\n", l, s, s->children);
	    Lst_Destroy(&s->cp, NOFREE);
#endif
	    Lst_Remove(l, ln);
	    free(s);
	    t |= 1;
	    return TRUE;
	}
#ifdef DEBUG_SRC
	else {
	    printf("keep: [l=%x] p=%x %d: ", l, s, s->children);
	    Lst_Every(&s->cp, PrintAddr);
	    printf("\n");
	}
#endif
    }

    return t;
}

/*-
 *-----------------------------------------------------------------------
 * SuffFindThem --
 *	Find the first existing file/target in the list srcs
 *
 * Results:
 *	The lowest structure in the chain of transformations
 *-----------------------------------------------------------------------
 */
static Src *
SuffFindThem(srcs, slst)
    Lst 	   srcs;	/* list of Src structures to search through */
    Lst 	   slst;
{
    Src 	   *s;		/* current Src */
    Src 	   *rs; 	/* returned Src */
    char	   *ptr;

    rs = NULL;

    while ((s = (Src *)Lst_DeQueue(srcs)) != NULL) {
	if (DEBUG(SUFF)) {
	    printf("\ttrying %s...", s->file);
	}

	/*
	 * A file is considered to exist if either a node exists in the
	 * graph for it or the file actually exists.
	 */
	if (Targ_FindNode(s->file, NULL, TARG_NOCREATE) != NULL) {
#ifdef DEBUG_SRC
	    printf("remove %x from %x\n", s, srcs);
#endif
	    rs = s;
	    break;
	}

	if ((ptr = Dir_FindFile(s->file, &s->suff->searchPath)) != NULL) {
	    rs = s;
#ifdef DEBUG_SRC
	    printf("remove %x from %x\n", s, srcs);
#endif
	    free(ptr);
	    break;
	}

	if (DEBUG(SUFF)) {
	    printf("not there\n");
	}

	SuffAddLevel(srcs, s);
	Lst_AtEnd(slst, s);
    }

    if (DEBUG(SUFF) && rs) {
	printf("got it\n");
    }
    return rs;
}

/*-
 *-----------------------------------------------------------------------
 * SuffFindCmds --
 *	See if any of the children of the target in the Src structure is
 *	one from which the target can be transformed. If there is one,
 *	a Src structure is put together for it and returned.
 *
 * Results:
 *	The Src structure of the "winning" child, or NULL if no such beast.
 *
 * Side Effects:
 *	A Src structure may be allocated.
 *-----------------------------------------------------------------------
 */
static Src *
SuffFindCmds(targ, slst)
    Src 	*targ;	/* Src structure to play with */
    Lst 	slst;
{
    LstNode		ln;	/* General-purpose list node */
    GNode		*t,	/* Target GNode */
			*s;	/* Source GNode */
    int 		prefLen;/* The length of the defined prefix */
    Suff		*suff;	/* Suffix on matching beastie */
    Src 		*ret;	/* Return value */
    const char		*cp;

    t = targ->node;
    prefLen = strlen(targ->pref);

    for (ln = Lst_First(&t->children); ln != NULL; ln = Lst_Adv(ln)) {
	s = (GNode *)Lst_Datum(ln);

	cp = strrchr(s->name, '/');
	if (cp == NULL) {
	    cp = s->name;
	} else {
	    cp++;
	}
	if (strncmp(cp, targ->pref, prefLen) == 0) {
	    /* The node matches the prefix ok, see if it has a known
	     * suffix.	*/
	    LstNode ln2;
	    ln2 = Lst_FindConst(&sufflist, SuffSuffHasNameP, &cp[prefLen]);
	    if (ln2 != NULL) {
		/*
		 * It even has a known suffix, see if there's a transformation
		 * defined between the node's suffix and the target's suffix.
		 *
		 * XXX: Handle multi-stage transformations here, too.
		 */
		suff = (Suff *)Lst_Datum(ln2);

		if (Lst_Member(&suff->parents, targ->suff) != NULL) {
		    /*
		     * Hot Damn! Create a new Src structure to describe
		     * this transformation (making sure to duplicate the
		     * source node's name so Suff_FindDeps can free it
		     * again (ick)), and return the new structure.
		     */
		    ret = emalloc(sizeof(Src));
		    ret->file = estrdup(s->name);
		    ret->pref = targ->pref;
		    ret->suff = suff;
		    ret->parent = targ;
		    ret->node = s;
		    ret->children = 0;
		    targ->children += 1;
#ifdef DEBUG_SRC
		    Lst_Init(&ret->cp);
		    printf("3 add %x %x\n", targ, ret);
		    Lst_AtEnd(&targ->cp, ret);
#endif
		    Lst_AtEnd(slst, ret);
		    if (DEBUG(SUFF)) {
			printf ("\tusing existing source %s\n", s->name);
		    }
		    return ret;
		}
	    }
	}
    }
    return NULL;
}

static void
SuffExpandVarChildren(after, cgn, pgn)
    LstNode	after;
    GNode	*cgn;
    GNode	*pgn;
{
    GNode	*gn;		/* New source 8) */
    char	*cp;		/* Expanded value */
    LIST	members;


    if (DEBUG(SUFF))
	printf("Expanding \"%s\"...", cgn->name);

    cp = Var_Subst(cgn->name, &pgn->context, TRUE);
    if (cp == NULL) {
	printf("Problem substituting in %s", cgn->name);
	printf("\n");
	return;
    }

    Lst_Init(&members);

    if (cgn->type & OP_ARCHV) {
	/*
	 * Node was an archive(member) target, so we want to call
	 * on the Arch module to find the nodes for us, expanding
	 * variables in the parent's context.
	 */
	char	*sacrifice = cp;

	(void)Arch_ParseArchive(&sacrifice, &members, &pgn->context);
    } else {
	/* Break the result into a vector of strings whose nodes
	 * we can find, then add those nodes to the members list.
	 * Unfortunately, we can't use brk_string because it
	 * doesn't understand about variable specifications with
	 * spaces in them...  */
	char	    *start, *cp2;

	for (start = cp; *start == ' ' || *start == '\t'; start++)
	    continue;
	for (cp2 = start; *cp2 != '\0';) {
	    if (isspace(*cp2)) {
		/* White-space -- terminate element, find the node,
		 * add it, skip any further spaces.  */
		gn = Targ_FindNode(start, cp2, TARG_CREATE);
		cp2++;
		Lst_AtEnd(&members, gn);
		while (isspace(*cp2))
		    cp2++;
		/* Adjust cp2 for increment at start of loop, but
		 * set start to first non-space.  */
		start = cp2;
	    } else if (*cp2 == '$')
		/* Start of a variable spec -- contact variable module
		 * to find the end so we can skip over it.  */
		cp2 += Var_ParseSkip(cp2, &pgn->context, NULL);
	    else if (*cp2 == '\\' && cp2[1] != '\0')
		/* Escaped something -- skip over it.  */
		cp2+=2;
	}

	if (cp2 != start) {
	    /* Stuff left over -- add it to the list too.  */
	    gn = Targ_FindNode(start, cp2, TARG_CREATE);
	    Lst_AtEnd(&members, gn);
	}
    }
    /* Add all elements of the members list to the parent node.  */
    while ((gn = (GNode *)Lst_DeQueue(&members)) != NULL) {
	if (DEBUG(SUFF))
	    printf("%s...", gn->name);
	if (Lst_Member(&pgn->children, gn) == NULL) {
	    Lst_Append(&pgn->children, after, gn);
	    after = Lst_Adv(after);
	    Lst_AtEnd(&gn->parents, pgn);
	    pgn->unmade++;
	}
    }
    /* Free the result.  */
    free(cp);
    if (DEBUG(SUFF))
	printf("\n");
}

static void
SuffExpandWildChildren(after, cgn, pgn)
    LstNode	after;
    GNode	*cgn;
    GNode	*pgn;
{
    LstNode	ln;		/* List element for old source */
    char	*cp;		/* Expanded value */

    LIST	exp;	    /* List of expansions */
    Lst 	path;	    /* Search path along which to expand */

    if (DEBUG(SUFF))
	printf("Wildcard expanding \"%s\"...", cgn->name);

    /* Find a path along which to expand the word.
     *
     * If the word has a known suffix, use that path.
     * If it has no known suffix and we're allowed to use the null
     *	 suffix, use its path.
     * Else use the default system search path.  */
    cp = cgn->name + strlen(cgn->name);
    ln = Lst_FindConst(&sufflist, SuffSuffIsSuffixP, cp);

    if (ln != NULL) {
	Suff	*s = (Suff *)Lst_Datum(ln);

	if (DEBUG(SUFF))
	    printf("suffix is \"%s\"...", s->name);
	path = &s->searchPath;
    } else
	/* Use default search path.  */
	path = &dirSearchPath;

    /* Expand the word along the chosen path. */
    Lst_Init(&exp);
    Dir_Expand(cgn->name, path, &exp);

    /* Fetch next expansion off the list and find its GNode.  */
    while ((cp = (char *)Lst_DeQueue(&exp)) != NULL) {
	GNode		*gn;		/* New source 8) */
	if (DEBUG(SUFF))
	    printf("%s...", cp);
	gn = Targ_FindNode(cp, NULL, TARG_CREATE);

	/* If gn isn't already a child of the parent, make it so and
	 * up the parent's count of unmade children.  */
	if (Lst_Member(&pgn->children, gn) == NULL) {
	    Lst_Append(&pgn->children, after, gn);
	    after = Lst_Adv(after);
	    Lst_AtEnd(&gn->parents, pgn);
	    pgn->unmade++;
	}
    }

    if (DEBUG(SUFF))
	printf("\n");
}

/*-
 *-----------------------------------------------------------------------
 * SuffExpandChildren --
 *	Expand the names of any children of a given node that contain
 *	variable invocations or file wildcards into actual targets.
 *
 * Side Effects:
 *	The expanded node is removed from the parent's list of children,
 *	and the parent's unmade counter is decremented, but other nodes
 *	may be added.
 *-----------------------------------------------------------------------
 */
static void
SuffExpandChildren(cgnp, pgnp)
    void	*cgnp;		/* Child to examine */
    void	*pgnp;		/* Parent node being processed */
{
    GNode	*cgn = (GNode *)cgnp;
    GNode	*pgn = (GNode *)pgnp;
    LstNode	ln;
    /* New nodes effectively take the place of the child, so we place them
     * after the child.  */
    ln = Lst_Member(&pgn->children, cgn);

    /* First do variable expansion -- this takes precedence over
     * wildcard expansion. If the result contains wildcards, they'll be gotten
     * to later since the resulting words are tacked on to the end of
     * the children list.  */
    if (strchr(cgn->name, '$') != NULL)
	SuffExpandVarChildren(ln, cgn, pgn);
    else if (Dir_HasWildcards(cgn->name))
	SuffExpandWildChildren(ln, cgn, pgn);
    else
	/* Third case: nothing to expand.  */
	return;

    /* Since the source was expanded, remove it from the list of children to
     * keep it from being processed.  */
    pgn->unmade--;
    Lst_Remove(&pgn->children, ln);
}

/*-
 *-----------------------------------------------------------------------
 * SuffApplyTransform --
 *	Apply a transformation rule, given the source and target nodes
 *	and suffixes.
 *
 * Results:
 *	TRUE if successful, FALSE if not.
 *
 * Side Effects:
 *	The source and target are linked and the commands from the
 *	transformation are added to the target node's commands list.
 *	All attributes but OP_DEPMASK and OP_TRANSFORM are applied
 *	to the target. The target also inherits all the sources for
 *	the transformation rule.
 *-----------------------------------------------------------------------
 */
static Boolean
SuffApplyTransform(tGn, sGn, t, s)
    GNode	*tGn;	/* Target node */
    GNode	*sGn;	/* Source node */
    Suff	*t;	/* Target suffix */
    Suff	*s;	/* Source suffix */
{
    LstNode	ln;	/* General node */
    LstNode	np;	    /* Next node for loop */
    char	*tname; /* Name of transformation rule */
    GNode	*gn;	/* Node for same */

    if (Lst_AddNew(&tGn->children, sGn) == SUCCESS) {
	/* Not already linked, so form the proper links between the
	 * target and source.  */
	Lst_AtEnd(&sGn->parents, tGn);
	tGn->unmade++;
    }

    if ((sGn->type & OP_OPMASK) == OP_DOUBLEDEP) {
	/* When a :: node is used as the implied source of a node, we have
	 * to link all its cohorts in as sources as well. Only the initial
	 * sGn gets the target in its iParents list, however, as that
	 * will be sufficient to get the .IMPSRC variable set for tGn.	*/
	for (ln=Lst_First(&sGn->cohorts); ln != NULL; ln=Lst_Adv(ln)) {
	    gn = (GNode *)Lst_Datum(ln);

	    if (Lst_AddNew(&tGn->children, gn) == SUCCESS) {
		/* Not already linked, so form the proper links between the
		 * target and source.  */
		Lst_AtEnd(&gn->parents, tGn);
		tGn->unmade++;
	    }
	}
    }
    /* Locate the transformation rule itself.  */
    tname = str_concat(s->name, t->name, 0);
    ln = Lst_FindConst(&transforms, SuffGNHasNameP, tname);
    free(tname);

    if (ln == NULL)
	/*
	 * Not really such a transformation rule (can happen when we're
	 * called to link an OP_MEMBER and OP_ARCHV node), so return
	 * FALSE.
	 */
	return FALSE;

    gn = (GNode *)Lst_Datum(ln);

    if (DEBUG(SUFF))
	printf("\tapplying %s -> %s to \"%s\"\n", s->name, t->name, tGn->name);

    /* Record last child for expansion purposes.  */
    ln = Lst_Last(&tGn->children);

    /* Pass the buck to Make_HandleUse to apply the rule.  */
    Make_HandleUse(gn, tGn);

    /* Deal with wildcards and variables in any acquired sources.  */
    for (ln = Lst_Succ(ln); ln != NULL; ln = np) {
    	np = Lst_Adv(ln);
	SuffExpandChildren(Lst_Datum(ln), tGn);
    }

    /* Keep track of another parent to which this beast is transformed so
     * the .IMPSRC variable can be set correctly for the parent.  */
    Lst_AtEnd(&sGn->iParents, tGn);

    return TRUE;
}


/*-
 *-----------------------------------------------------------------------
 * SuffFindArchiveDeps --
 *	Locate dependencies for an OP_ARCHV node.
 *
 * Side Effects:
 *	Same as Suff_FindDeps
 *-----------------------------------------------------------------------
 */
static void
SuffFindArchiveDeps(gn, slst)
    GNode	*gn;	    /* Node for which to locate dependencies */
    Lst 	slst;
{
    char	*eoarch;    /* End of archive portion */
    char	*eoname;    /* End of member portion */
    GNode	*mem;	    /* Node for member */
    Suff	*ms;	    /* Suffix descriptor for member */
    char	*name;	    /* Start of member's name */

    /* The node is an archive(member) pair. so we must find a suffix
     * for both of them.  */
    eoarch = strchr(gn->name, '(');
    if (eoarch == NULL)
	return;

    name = eoarch + 1;

    eoname = strchr(name, ')');
    if (eoname == NULL)
	return;

    /* To simplify things, call Suff_FindDeps recursively on the member now,
     * so we can simply compare the member's .PREFIX and .TARGET variables
     * to locate its suffix. This allows us to figure out the suffix to
     * use for the archive without having to do a quadratic search over the
     * suffix list, backtracking for each one...  */
    mem = Targ_FindNode(name, eoname, TARG_CREATE);
    SuffFindDeps(mem, slst);

    /* Create the link between the two nodes right off. */
    if (Lst_AddNew(&gn->children, mem) == SUCCESS) {
	Lst_AtEnd(&mem->parents, gn);
	gn->unmade++;
    }

    /* Copy variables from member node to this one.  */
    Varq_Set(TARGET_INDEX, Varq_Value(TARGET_INDEX, mem), gn);
    Varq_Set(PREFIX_INDEX, Varq_Value(PREFIX_INDEX, mem), gn);

    ms = mem->suffix;
    if (ms == NULL) {
	/* Didn't know what it was -- use .NULL suffix if not in make mode.  */
	if (DEBUG(SUFF))
	    printf("using null suffix\n");
	ms = suffNull;
    }


    /* Set the other two local variables required for this target.  */
    Varq_Set(MEMBER_INDEX, mem->name, gn);
    Varq_Set(ARCHIVE_INDEX, gn->name, gn);

    if (ms != NULL) {
	/*
	 * Member has a known suffix, so look for a transformation rule from
	 * it to a possible suffix of the archive. Rather than searching
	 * through the entire list, we just look at suffixes to which the
	 * member's suffix may be transformed...
	 */
	LstNode     ln;

	/* Use first matching suffix...  */
	ln = Lst_FindConst(&ms->parents, SuffSuffIsSuffixP, eoarch);

	if (ln != NULL) {
	    /* Got one -- apply it.  */
	    if (!SuffApplyTransform(gn, mem, (Suff *)Lst_Datum(ln), ms) &&
		DEBUG(SUFF))
		printf("\tNo transformation from %s -> %s\n",
		       ms->name, ((Suff *)Lst_Datum(ln))->name);
	}
    }

    /* Pretend gn appeared to the left of a dependency operator so
     * the user needn't provide a transformation from the member to the
     * archive.  */
    if (OP_NOP(gn->type))
	gn->type |= OP_DEPENDS;

    /* Flag the member as such so we remember to look in the archive for
     * its modification time.  */
    mem->type |= OP_MEMBER;
}

/*-
 *-----------------------------------------------------------------------
 * SuffFindNormalDeps --
 *	Locate implicit dependencies for regular targets.
 *
 * Side Effects:
 *	Same as Suff_FindDeps...
 *-----------------------------------------------------------------------
 */
static void
SuffFindNormalDeps(gn, slst)
    GNode	*gn;	    /* Node for which to find sources */
    Lst 	slst;
{
    char	*eoname;    /* End of name */
    char	*sopref;    /* Start of prefix */
    LstNode	ln;	    /* Next suffix node to check */
    LstNode	np;
    LIST	srcs;	    /* List of sources at which to look */
    LIST	targs;	    /* List of targets to which things can be
			     * transformed. They all have the same file,
			     * but different suff and pref fields */
    Src 	*bottom;    /* Start of found transformation path */
    Src 	*src;	    /* General Src pointer */
    char	*pref;	    /* Prefix to use */
    Src 	*targ;	    /* General Src target pointer */


    eoname = gn->name + strlen(gn->name);

    sopref = gn->name;

    /* Begin at the beginning...  */
    ln = Lst_First(&sufflist);
    Lst_Init(&srcs);
    Lst_Init(&targs);

    /* We're caught in a catch-22 here. On the one hand, we want to use any
     * transformation implied by the target's sources, but we can't examine
     * the sources until we've expanded any variables/wildcards they may hold,
     * and we can't do that until we've set up the target's local variables
     * and we can't do that until we know what the proper suffix for the
     * target is (in case there are two suffixes one of which is a suffix of
     * the other) and we can't know that until we've found its implied
     * source, which we may not want to use if there's an existing source
     * that implies a different transformation.
     *
     * In an attempt to get around this, which may not work all the time,
     * but should work most of the time, we look for implied sources first,
     * checking transformations to all possible suffixes of the target,
     * use what we find to set the target's local variables, expand the
     * children, then look for any overriding transformations they imply.
     * Should we find one, we discard the one we found before.	*/

    while (ln != NULL) {
	/* Look for next possible suffix...  */
	ln = Lst_FindFromConst(ln, SuffSuffIsSuffixP, eoname);

	if (ln != NULL) {
	    int     prefLen;	    /* Length of the prefix */
	    Src     *targ;

	    /* Allocate a Src structure to which things can be transformed.  */
	    targ = emalloc(sizeof(Src));
	    targ->file = estrdup(gn->name);
	    targ->suff = (Suff *)Lst_Datum(ln);
	    targ->node = gn;
	    targ->parent = NULL;
	    targ->children = 0;
#ifdef DEBUG_SRC
	    Lst_Init(&targ->cp);
#endif

	    /* Allocate room for the prefix, whose end is found by subtracting
	     * the length of the suffix from the end of the name.  */
	    prefLen = (eoname - targ->suff->nameLen) - sopref;
	    targ->pref = emalloc(prefLen + 1);
	    memcpy(targ->pref, sopref, prefLen);
	    targ->pref[prefLen] = '\0';

	    /* Add nodes from which the target can be made.  */
	    SuffAddLevel(&srcs, targ);

	    /* Record the target so we can nuke it.  */
	    Lst_AtEnd(&targs, targ);

	    /* Search from this suffix's successor...  */
	    ln = Lst_Succ(ln);
	}
    }

    /* Handle target of unknown suffix...  */
    if (Lst_IsEmpty(&targs) && suffNull != NULL) {
	if (DEBUG(SUFF)) {
	    printf("\tNo known suffix on %s. Using .NULL suffix\n", gn->name);
	}

	targ = emalloc(sizeof(Src));
	targ->file = estrdup(gn->name);
	targ->suff = suffNull;
	targ->node = gn;
	targ->parent = NULL;
	targ->children = 0;
	targ->pref = estrdup(sopref);
#ifdef DEBUG_SRC
	Lst_Init(&targ->cp);
#endif

	/* Only use the default suffix rules if we don't have commands
	 * or dependencies defined for this gnode.  */
	if (Lst_IsEmpty(&gn->commands) && Lst_IsEmpty(&gn->children))
	    SuffAddLevel(&srcs, targ);
	else {
	    if (DEBUG(SUFF))
		printf("not ");
	}

	if (DEBUG(SUFF))
	    printf("adding suffix rules\n");

	Lst_AtEnd(&targs, targ);
    }

    /* Using the list of possible sources built up from the target suffix(es),
     * try and find an existing file/target that matches.  */
    bottom = SuffFindThem(&srcs, slst);

    if (bottom == NULL) {
	/* No known transformations -- use the first suffix found for setting
	 * the local variables.  */
	if (!Lst_IsEmpty(&targs))
	    targ = (Src *)Lst_Datum(Lst_First(&targs));
	else
	    targ = NULL;
    } else {
	/* Work up the transformation path to find the suffix of the
	 * target to which the transformation was made.  */
	for (targ = bottom; targ->parent != NULL; targ = targ->parent)
	    continue;
    }

    /* The .TARGET variable we always set to be the name at this point,
     * since it's only set to the path if the thing is only a source and
     * if it's only a source, it doesn't matter what we put here as far
     * as expanding sources is concerned, since it has none...	*/
    Varq_Set(TARGET_INDEX, gn->name, gn);

    pref = targ != NULL ? targ->pref : gn->name;
    Varq_Set(PREFIX_INDEX, pref, gn);

    /* Now we've got the important local variables set, expand any sources
     * that still contain variables or wildcards in their names.  */
    for (ln = Lst_First(&gn->children); ln != NULL; ln = np) {
    	np = Lst_Adv(ln);
	SuffExpandChildren(Lst_Datum(ln), gn);
    }

    if (targ == NULL) {
	if (DEBUG(SUFF))
	    printf("\tNo valid suffix on %s\n", gn->name);

sfnd_abort:
	/* Deal with finding the thing on the default search path if the
	 * node is only a source (not on the lhs of a dependency operator
	 * or [XXX] it has neither children or commands).  */
	if (OP_NOP(gn->type) ||
	    (Lst_IsEmpty(&gn->children) && Lst_IsEmpty(&gn->commands)))
	{
	    gn->path = Dir_FindFile(gn->name,
				    (targ == NULL ? &dirSearchPath :
				     &targ->suff->searchPath));
	    if (gn->path != NULL) {
		char *ptr;
		Varq_Set(TARGET_INDEX, gn->path, gn);

		if (targ != NULL) {
		    /* Suffix known for the thing -- trim the suffix off
		     * the path to form the proper .PREFIX variable.  */
		    int 	savep = strlen(gn->path) - targ->suff->nameLen;
		    char	savec;

		    gn->suffix = targ->suff;

		    savec = gn->path[savep];
		    gn->path[savep] = '\0';

		    if ((ptr = strrchr(gn->path, '/')) != NULL)
			ptr++;
		    else
			ptr = gn->path;

		    Varq_Set(PREFIX_INDEX, ptr, gn);

		    gn->path[savep] = savec;
		} else {
		    /* The .PREFIX gets the full path if the target has
		     * no known suffix.  */
		    gn->suffix = NULL;

		    if ((ptr = strrchr(gn->path, '/')) != NULL)
			ptr++;
		    else
			ptr = gn->path;

		    Varq_Set(PREFIX_INDEX, ptr, gn);
		}
	    }
	} else {
	    /* Not appropriate to search for the thing -- set the
	     * path to be the name so Dir_MTime won't go grovelling for
	     * it.  */
	    gn->suffix = targ == NULL ? NULL : targ->suff;
	    efree(gn->path);
	    gn->path = estrdup(gn->name);
	}

	goto sfnd_return;
    }

    /* If the suffix indicates that the target is a library, mark that in
     * the node's type field.  */
    if (targ->suff->flags & SUFF_LIBRARY) {
	gn->type |= OP_LIB;
    }

    /* Check for overriding transformation rule implied by sources.  */
    if (!Lst_IsEmpty(&gn->children)) {
	src = SuffFindCmds(targ, slst);

	if (src != NULL) {
	    /* Free up all the Src structures in the transformation path
	     * up to, but not including, the parent node.  */
	    while (bottom && bottom->parent != NULL) {
		(void)Lst_AddNew(slst, bottom);
		bottom = bottom->parent;
	    }
	    bottom = src;
	}
    }

    if (bottom == NULL) {
	/* No idea from where it can come -- return now.  */
	goto sfnd_abort;
    }

    /* We now have a list of Src structures headed by 'bottom' and linked via
     * their 'parent' pointers. What we do next is create links between
     * source and target nodes (which may or may not have been created)
     * and set the necessary local variables in each target. The
     * commands for each target are set from the commands of the
     * transformation rule used to get from the src suffix to the targ
     * suffix. Note that this causes the commands list of the original
     * node, gn, to be replaced by the commands of the final
     * transformation rule. Also, the unmade field of gn is incremented.
     * Etc.  */
    if (bottom->node == NULL) {
	bottom->node = Targ_FindNode(bottom->file, NULL, TARG_CREATE);
    }

    for (src = bottom; src->parent != NULL; src = src->parent) {
	targ = src->parent;

	src->node->suffix = src->suff;

	if (targ->node == NULL) {
	    targ->node = Targ_FindNode(targ->file, NULL, TARG_CREATE);
	}

	SuffApplyTransform(targ->node, src->node,
			   targ->suff, src->suff);

	if (targ->node != gn) {
	    /* Finish off the dependency-search process for any nodes
	     * between bottom and gn (no point in questing around the
	     * filesystem for their implicit source when it's already
	     * known). Note that the node can't have any sources that
	     * need expanding, since SuffFindThem will stop on an existing
	     * node, so all we need to do is set the standard and System V
	     * variables.  */
	    targ->node->type |= OP_DEPS_FOUND;

	    Varq_Set(PREFIX_INDEX, targ->pref, targ->node);

	    Varq_Set(TARGET_INDEX, targ->node->name, targ->node);
	}
    }

    gn->suffix = src->suff;

    /* So Dir_MTime doesn't go questing for it...  */
    efree(gn->path);
    gn->path = estrdup(gn->name);

    /* Nuke the transformation path and the Src structures left over in the
     * two lists.  */
sfnd_return:
    if (bottom)
	(void)Lst_AddNew(slst, bottom);

    while (SuffRemoveSrc(&srcs) || SuffRemoveSrc(&targs))
	continue;

    Lst_ConcatDestroy(slst, &srcs);
    Lst_ConcatDestroy(slst, &targs);
}


/*-
 *-----------------------------------------------------------------------
 * Suff_FindDeps  --
 *	Find implicit sources for the target described by the graph node
 *	gn
 *
 * Side Effects:
 *	Nodes are added to the graph below the passed-in node. The nodes
 *	are marked to have their IMPSRC variable filled in. The
 *	PREFIX variable is set for the given node and all its
 *	implied children.
 *
 * Notes:
 *	The path found by this target is the shortest path in the
 *	transformation graph, which may pass through non-existent targets,
 *	to an existing target. The search continues on all paths from the
 *	root suffix until a file is found. I.e. if there's a path
 *	.o -> .c -> .l -> .l,v from the root and the .l,v file exists but
 *	the .c and .l files don't, the search will branch out in
 *	all directions from .o and again from all the nodes on the
 *	next level until the .l,v node is encountered.
 *-----------------------------------------------------------------------
 */

void
Suff_FindDeps(gn)
    GNode *gn;
{

    SuffFindDeps(gn, &srclist);
    while (SuffRemoveSrc(&srclist))
	continue;
}


static void
SuffFindDeps(gn, slst)
    GNode	  *gn;		/* node we're dealing with */
    Lst 	  slst;
{
    if (gn->type & OP_DEPS_FOUND) {
	/*
	 * If dependencies already found, no need to do it again...
	 */
	return;
    } else {
	gn->type |= OP_DEPS_FOUND;
    }

    if (DEBUG(SUFF)) {
	printf("SuffFindDeps (%s)\n", gn->name);
    }

    if (gn->type & OP_ARCHV) {
	SuffFindArchiveDeps(gn, slst);
    } else if (gn->type & OP_LIB) {
	/*
	 * If the node is a library, it is the arch module's job to find it
	 * and set the TARGET variable accordingly. We merely provide the
	 * search path, assuming all libraries end in ".a" (if the suffix
	 * hasn't been defined, there's nothing we can do for it, so we just
	 * set the TARGET variable to the node's name in order to give it a
	 * value).
	 */
	LstNode ln;
	Suff	*s;

	ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, LIBSUFF);
	if (ln != NULL) {
	    gn->suffix = s = (Suff *)Lst_Datum(ln);
	    Arch_FindLib(gn, &s->searchPath);
	} else {
	    gn->suffix = NULL;
	    Varq_Set(TARGET_INDEX, gn->name, gn);
	}
	/*
	 * Because a library (-lfoo) target doesn't follow the standard
	 * filesystem conventions, we don't set the regular variables for
	 * the thing. .PREFIX is simply made empty...
	 */
	Varq_Set(PREFIX_INDEX, "", gn);
    } else
	SuffFindNormalDeps(gn, slst);
}

/*-
 *-----------------------------------------------------------------------
 * Suff_SetNull --
 *	Define which suffix is the null suffix.
 *
 * Side Effects:
 *	'suffNull' is altered.
 *
 * Notes:
 *	Need to handle the changing of the null suffix gracefully so the
 *	old transformation rules don't just go away.
 *-----------------------------------------------------------------------
 */
void
Suff_SetNull(name)
    char    *name;	    /* Name of null suffix */
{
    Suff    *s;
    LstNode ln;

    ln = Lst_FindConst(&sufflist, SuffSuffHasNameP, name);
    if (ln != NULL) {
	s = (Suff *)Lst_Datum(ln);
	if (suffNull != NULL) {
	    suffNull->flags &= ~SUFF_NULL;
	}
	s->flags |= SUFF_NULL;
	/*
	 * XXX: Here's where the transformation mangling would take place
	 */
	suffNull = s;
    } else {
	Parse_Error(PARSE_WARNING, "Desired null suffix %s not defined.",
		     name);
    }
}

/*-
 *-----------------------------------------------------------------------
 * Suff_Init --
 *	Initialize suffixes module
 *
 * Side Effects:
 *	Many
 *-----------------------------------------------------------------------
 */
void
Suff_Init()
{
    Lst_Init(&sufflist);
#ifdef CLEANUP
    Lst_Init(&suffClean);
#endif
    Lst_Init(&srclist);
    Lst_Init(&transforms);

    sNum = 0;
    /*
     * Create null suffix for single-suffix rules (POSIX). The thing doesn't
     * actually go on the suffix list or everyone will think that's its
     * suffix.
     */
    emptySuff = suffNull = emalloc(sizeof(Suff));

    suffNull->name =	    estrdup("");
    suffNull->nameLen =     0;
    Lst_Init(&suffNull->searchPath);
    Dir_Concat(&suffNull->searchPath, &dirSearchPath);
    Lst_Init(&suffNull->children);
    Lst_Init(&suffNull->parents);
    Lst_Init(&suffNull->ref);
    suffNull->sNum =	    sNum++;
    suffNull->flags =	    SUFF_NULL;

}


/*-
 *----------------------------------------------------------------------
 * Suff_End --
 *	Cleanup the this module
 *
 * Side Effects:
 *	The memory is free'd.
 *----------------------------------------------------------------------
 */

void
Suff_End()
{
#ifdef CLEANUP
    Lst_Destroy(&sufflist, SuffFree);
    Lst_Destroy(&suffClean, SuffFree);
    if (suffNull)
	SuffFree(suffNull);
    Lst_Destroy(&srclist, NOFREE);
    Lst_Destroy(&transforms, NOFREE);
#endif
}


/********************* DEBUGGING FUNCTIONS **********************/

static void SuffPrintName(s)
    void *s;
{
    printf("%s ", ((Suff *)s)->name);
}

static void
SuffPrintSuff(sp)
    void *sp;
{
    Suff    *s = (Suff *)sp;
    int     flags;
    int     flag;

    printf("# `%s' ", s->name);

    flags = s->flags;
    if (flags) {
	fputs(" (", stdout);
	while (flags) {
	    flag = 1 << (ffs(flags) - 1);
	    flags &= ~flag;
	    switch (flag) {
		case SUFF_NULL:
		    printf("NULL");
		    break;
		case SUFF_INCLUDE:
		    printf("INCLUDE");
		    break;
		case SUFF_LIBRARY:
		    printf("LIBRARY");
		    break;
	    }
	    fputc(flags ? '|' : ')', stdout);
	}
    }
    fputc('\n', stdout);
    printf("#\tTo: ");
    Lst_Every(&s->parents, SuffPrintName);
    fputc('\n', stdout);
    printf("#\tFrom: ");
    Lst_Every(&s->children, SuffPrintName);
    fputc('\n', stdout);
    printf("#\tSearch Path: ");
    Dir_PrintPath(&s->searchPath);
    fputc('\n', stdout);
}

static void
SuffPrintTrans(tp)
    void *tp;
{
    GNode   *t = (GNode *)tp;

    printf("%-16s: ", t->name);
    Targ_PrintType(t->type);
    fputc('\n', stdout);
    Lst_Every(&t->commands, Targ_PrintCmd);
    fputc('\n', stdout);
}

void
Suff_PrintAll()
{
    printf("#*** Suffixes:\n");
    Lst_Every(&sufflist, SuffPrintSuff);

    printf("#*** Transformations:\n");
    Lst_Every(&transforms, SuffPrintTrans);
}