[BACK]Return to dir.c CVS log [TXT][DIR] Up to [local] / src / usr.bin / make

File: [local] / src / usr.bin / make / dir.c (download)

Revision 1.31, Thu May 3 13:41:03 2001 UTC (23 years, 1 month ago) by espie
Branch: MAIN
Changes since 1.30: +418 -469 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: dir.c,v 1.31 2001/05/03 13:41:03 espie Exp $ */
/*	$NetBSD: dir.c,v 1.14 1997/03/29 16:51:26 christos Exp $	*/

/*
 * Copyright (c) 1999 Marc Espie.
 *
 * Extensive code changes for the OpenBSD project.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT 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 OPENBSD
 * PROJECT 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) 1988, 1989, 1990 The Regents of the University of California.
 * Copyright (c) 1988, 1989 by Adam de Boor
 * 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.
 */

/*-
 * dir.c --
 *	Directory searching using wildcards and/or normal names...
 *	Used both for source wildcarding in the Makefile and for finding
 *	implicit sources.
 *
 * The interface for this module is:
 *	Dir_Init	    Initialize the module.
 *
 *	Dir_End 	    Cleanup the module.
 *
 *	Dir_HasWildcards    Returns TRUE if the name given it needs to
 *			    be wildcard-expanded.
 *
 *	Dir_Expand	    Given a pattern and a path, return a Lst of names
 *			    which match the pattern on the search path.
 *
 *	Dir_FindFile	    Searches for a file on a given search path.
 *			    If it exists, the entire path is returned.
 *			    Otherwise NULL is returned.
 *
 *	Dir_MTime	    Return the modification time of a node. The file
 *			    is searched for along the default search path.
 *			    The path and mtime fields of the node are filled
 *			    in.
 *
 *	Dir_AddDir	    Add a directory to a search path.
 *
 *	Dir_MakeFlags	    Given a search path and a command flag, create
 *			    a string with each of the directories in the path
 *			    preceded by the command flag and all of them
 *			    separated by a space.
 *
 *	Dir_Destroy	    Destroy an element of a search path. Frees up all
 *			    things that can be freed for the element as long
 *			    as the element is no longer referenced by any other
 *			    search path.
 *
 * For debugging:
 *	Dir_PrintDirectories	Print stats about the directory cache.
 */

#include <stddef.h>
#include <stdio.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include "make.h"
#include "ohash.h"
#include "dir.h"

#ifndef lint
#if 0
static char sccsid[] = "@(#)dir.c	8.2 (Berkeley) 1/2/94";
#else
UNUSED
static char rcsid[] = "$OpenBSD: dir.c,v 1.31 2001/05/03 13:41:03 espie Exp $";
#endif
#endif /* not lint */

/*	A search path consists of a Lst of Path structures. A Path structure
 *	has in it the name of the directory and a hash table of all the files
 *	in the directory. This is used to cut down on the number of system
 *	calls necessary to find implicit dependents and their like. Since
 *	these searches are made before any actions are taken, we need not
 *	worry about the directory changing due to creation commands. If this
 *	hampers the style of some makefiles, they must be changed.
 *
 *	A list of all previously-read directories is kept in the
 *	openDirectories cache.
 *
 *	The need for the caching of whole directories is brought about by
 *	the multi-level transformation code in suff.c, which tends to search
 *	for far more files than regular make does. In the initial
 *	implementation, the amount of time spent performing "stat" calls was
 *	truly astronomical. The problem with hashing at the start is,
 *	of course, that pmake doesn't then detect changes to these directories
 *	during the course of the make. Three possibilities suggest themselves:
 *
 *	    1) just use stat to test for a file's existence. As mentioned
 *	       above, this is very inefficient due to the number of checks
 *	       engendered by the multi-level transformation code.
 *	    2) use readdir() and company to search the directories, keeping
 *	       them open between checks. I have tried this and while it
 *	       didn't slow down the process too much, it could severely
 *	       affect the amount of parallelism available as each directory
 *	       open would take another file descriptor out of play for
 *	       handling I/O for another job. Given that it is only recently
 *	       that UNIX OS's have taken to allowing more than 20 or 32
 *	       file descriptors for a process, this doesn't seem acceptable
 *	       to me.
 *	    3) record the mtime of the directory in the Path structure and
 *	       verify the directory hasn't changed since the contents were
 *	       hashed. This will catch the creation or deletion of files,
 *	       but not the updating of files. However, since it is the
 *	       creation and deletion that is the problem, this could be
 *	       a good thing to do. Unfortunately, if the directory (say ".")
 *	       were fairly large and changed fairly frequently, the constant
 *	       rehashing could seriously degrade performance. It might be
 *	       good in such cases to keep track of the number of rehashes
 *	       and if the number goes over a (small) limit, resort to using
 *	       stat in its place.
 *
 *	An additional thing to consider is that pmake is used primarily
 *	to create C programs and until recently pcc-based compilers refused
 *	to allow you to specify where the resulting object file should be
 *	placed. This forced all objects to be created in the current
 *	directory. This isn't meant as a full excuse, just an explanation of
 *	some of the reasons for the caching used here.
 *
 *	One more note: the location of a target's file is only performed
 *	on the downward traversal of the graph and then only for terminal
 *	nodes in the graph. This could be construed as wrong in some cases,
 *	but prevents inadvertent modification of files when the "installed"
 *	directory for a file is provided in the search path.
 *
 *	Another data structure maintained by this module is an mtime
 *	cache used when the searching of cached directories fails to find
 *	a file. In the past, Dir_FindFile would simply perform an access()
 *	call in such a case to determine if the file could be found using
 *	just the name given. When this hit, however, all that was gained
 *	was the knowledge that the file existed. Given that an access() is
 *	essentially a stat() without the copyout() call, and that the same
 *	filesystem overhead would have to be incurred in Dir_MTime, it made
 *	sense to replace the access() with a stat() and record the mtime
 *	in a cache for when Dir_MTime was actually called.  */

LIST	      dirSearchPath;		/* main search path */

/* Variables for gathering statistics on the efficiency of the hashing
 * mechanism.  */
static int    hits,			/* Found in directory cache */
	      misses,			/* Sad, but not evil misses */
	      nearmisses,		/* Found under search path */
	      bigmisses;		/* Sought by itself */

static Path	  *dot; 		/* contents of current directory */

struct file_stamp {
	TIMESTAMP mtime;		/* time stamp... */
	char name[1];			/* ...for that file.  */
};

static struct ohash   openDirectories;	/* cache all open directories */

static struct ohash mtimes;  /* Results of doing a last-resort stat in
			     * Dir_FindFile -- if we have to go to the
			     * system to find the file, we might as well
			     * have its mtime on record. XXX: If this is done
			     * way early, there's a chance other rules will
			     * have already updated the file, in which case
			     * we'll update it again. Generally, there won't
			     * be two rules to update a single file, so this
			     * should be ok, but... */


/* There are three distinct hash structures:
 * - to collate files's last modification times (global mtimes)
 * - to collate file names (in each Path structure)
 * - to collate known directories (global openDirectories).  */
static struct ohash_info stamp_info = { offsetof(struct file_stamp, name),
    NULL, hash_alloc, hash_free, element_alloc };

static struct ohash_info file_info = { 0,
    NULL, hash_alloc, hash_free, element_alloc };

static struct ohash_info dir_info = { offsetof(Path, name),
    NULL, hash_alloc, hash_free, element_alloc };

static void record_stamp(const char *, TIMESTAMP);
static void add_file(Path *, const char *);
static char *find_file_hash(Path *, const char *, const char *, u_int32_t);
static struct file_stamp *find_stampi(const char *, const char *);
static void free_hash(struct ohash *);



static Path *DirReaddir(const char *, const char *);
static void DirMatchFiles(const char *, Path *, Lst);
static void PathMatchFiles(const char *, Lst, Lst);
static void DirPrintWord(void *);
static void DirPrintDir(void *);
static void DirExpandWild(const char *, Lst, Lst);
static void DirExpandCurly(const char *, Lst, Lst);

static void
record_stamp(file, t)
    const char		*file;
    TIMESTAMP		t;
{
    unsigned		slot;
    const char		*end = NULL;
    struct file_stamp	*n;

    slot = ohash_qlookupi(&mtimes, file, &end);
    n = ohash_find(&mtimes, slot);
    if (n)
	n->mtime = t;
    else {
	n = ohash_create_entry(&stamp_info, file, &end);
	n->mtime = t;
	ohash_insert(&mtimes, slot, n);
    }
}

static struct file_stamp *
find_stampi(file, end)
    const char	*file;
    const char	*end;
{
    return ohash_find(&mtimes, ohash_qlookupi(&mtimes, file, &end));
}

static void
add_file(p, file)
    Path		*p;
    const char		*file;
{
    unsigned		slot;
    const char		*end = NULL;
    char		*n;
    struct ohash 	*h = &p->files;

    slot = ohash_qlookupi(h, file, &end);
    n = ohash_find(h, slot);
    if (n == NULL) {
	n = ohash_create_entry(&file_info, file, &end);
	ohash_insert(h, slot, n);
    }
}

static char *
find_file_hash(p, file, e, hv)
    Path		*p;
    const char		*file;
    const char		*e;
    u_int32_t		hv;
{
    struct ohash 	*h = &p->files;

    return ohash_find(h, ohash_lookup_interval(h, file, e, hv));
}

static void
free_hash(h)
    struct ohash 	*h;
{
    void		*e;
    unsigned		i;

    for (e = ohash_first(h, &i); e != NULL; e = ohash_next(h, &i))
	free(e);
    ohash_delete(h);
}

/*-
 *-----------------------------------------------------------------------
 * Dir_Init --
 *	initialize things for this module
 *
 * Side Effects:
 *	cache the current directory
 *-----------------------------------------------------------------------
 */
void
Dir_Init()
{
    Lst_Init(&dirSearchPath);
    ohash_init(&openDirectories, 4, &dir_info);
    ohash_init(&mtimes, 4, &stamp_info);

    dot = DirReaddir(".", NULL);

    if (!dot)
    	Error("Can't access current directory");

    /* We always need to have dot around, so we increment its reference count
     * to make sure it won't be destroyed.  */
    dot->refCount++;
}

/*-
 *-----------------------------------------------------------------------
 * Dir_End --
 *	cleanup things for this module
 *-----------------------------------------------------------------------
 */
void
Dir_End()
{
#ifdef CLEANUP
    struct Path *p;
    unsigned int i;

    dot->refCount--;
    Dir_Destroy(dot);
    Lst_Destroy(&dirSearchPath, Dir_Destroy);
    for (p = ohash_first(&openDirectories, &i); p != NULL;
	p = ohash_next(&openDirectories, &i))
	    Dir_Destroy(p);
    ohash_delete(&openDirectories);
    free_hash(&mtimes);
#endif
}

/*-
 *-----------------------------------------------------------------------
 * Dir_HasWildcards  --
 *	see if the given name has any wildcard characters in it
 *	be careful not to expand unmatching brackets or braces.
 *	XXX: This code is not 100% correct. ([^]] fails etc.)
 *-----------------------------------------------------------------------
 */
Boolean
Dir_HasWildcards(name)
    const char		*name;	/* name to check */
{
    const char		*cp;
    Boolean		wild = FALSE;
    unsigned long	brace = 0, bracket = 0;

    for (cp = name; *cp != '\0'; cp++) {
	switch (*cp) {
	case '{':
	    brace++;
	    wild = TRUE;
	    break;
	case '}':
	    if (brace == 0)
		return FALSE;
	    brace--;
	    break;
	case '[':
	    bracket++;
	    wild = TRUE;
	    break;
	case ']':
	    if (bracket == 0)
		return FALSE;
	    bracket--;
	    break;
	case '?':
	case '*':
	    wild = TRUE;
	    break;
	default:
	    break;
	}
    }
    return wild && bracket == 0 && brace == 0;
}

/*-
 *-----------------------------------------------------------------------
 * DirMatchFiles --
 *	Given a pattern and a Path structure, see if any files
 *	match the pattern and add their names to the 'expansions' list if
 *	any do. This is incomplete -- it doesn't take care of patterns like
 *	src / *src / *.c properly (just *.c on any of the directories), but it
 *	will do for now.
 *
 * Side Effects:
 *	The directory will be fully hashed when this is done.
 *-----------------------------------------------------------------------
 */
static void
DirMatchFiles(pattern, p, expansions)
    const char		*pattern;	/* Pattern to look for */
    Path		*p;		/* Directory to search */
    Lst 		expansions;	/* Place to store the results */
{
    unsigned int	search; 	/* Index into the directory's table */
    const char		*entry; 	/* Current entry in the table */
    Boolean		isDot;		/* Is the directory "." ? */

    isDot = p->name[0] == '.' && p->name[1] == '\0';

    for (entry = ohash_first(&p->files, &search); entry != NULL;
	 entry = ohash_next(&p->files, &search)) {
	/* See if the file matches the given pattern. We follow the UNIX
	 * convention that dot files will only be found if the pattern
	 * begins with a dot (the hashing scheme doesn't hash . or ..,
	 * so they won't match `.*'.  */
	if (*pattern != '.' && *entry == '.')
	    continue;
	if (Str_Match(entry, pattern))
	    Lst_AtEnd(expansions,
		isDot ? estrdup(entry) : str_concat(p->name, entry, '/'));
    }
}

/*-
 *-----------------------------------------------------------------------
 * PathMatchFiles --
 *	Traverse directories in the path, calling DirMatchFiles for each.
 *	NOTE: This doesn't handle patterns in directories.
 *-----------------------------------------------------------------------
 */
static void
PathMatchFiles(word, path, expansions)
    const char	*word;		/* Word to expand */
    Lst 	path;		/* Path on which to look */
    Lst 	expansions;	/* Place to store the result */
{
    LstNode	ln;		/* Current node */

    for (ln = Lst_First(path); ln != NULL; ln = Lst_Adv(ln))
	DirMatchFiles(word, (Path *)Lst_Datum(ln), expansions);
}

/*-
 *-----------------------------------------------------------------------
 * DirPrintWord --
 *	Print a word in the list of expansions. Callback for Dir_Expand
 *	when DEBUG(DIR), via Lst_ForEach.
 *-----------------------------------------------------------------------
 */
static void
DirPrintWord(word)
    void	*word;
{
    printf("%s ", (char *)word);
}

/*-
 *-----------------------------------------------------------------------
 * DirExpandWild:
 *	Expand all wild cards in a fully qualified name, except for
 *	curly braces.
 *-----------------------------------------------------------------------
 */
static void
DirExpandWild(word, path, expansions)
    const char	*word;		/* the word to expand */
    Lst 	path;		/* the list of directories in which to find
				 * the resulting files */
    Lst 	expansions;	/* the list on which to place the results */
{
    const char	*cp;
    const char	*slash; 	/* keep track of first slash before wildcard */

    slash = strchr(word, '/');
    if (slash == NULL) {
	/* First the files in dot.  */
	DirMatchFiles(word, dot, expansions);

	/* Then the files in every other directory on the path.  */
	PathMatchFiles(word, path, expansions);
	return;
    }
    /* The thing has a directory component -- find the first wildcard
     * in the string.  */
    slash = word;
    for (cp = word; *cp; cp++) {
	if (*cp == '/')
	    slash = cp;
	if (*cp == '?' || *cp == '[' || *cp == '*') {

	    if (slash != word) {
		char	*dirpath;

		/* If the glob isn't in the first component, try and find
		 * all the components up to the one with a wildcard.  */
		dirpath = Dir_FindFilei(word, slash+1, path);
		/* dirpath is null if we can't find the leading component
		 * XXX: Dir_FindFile won't find internal components.
		 * i.e. if the path contains ../Etc/Object and we're
		 * looking for Etc, it won't be found. */
		if (dirpath != NULL) {
		    char *dp = &dirpath[strlen(dirpath) - 1];
		    LIST temp;

		    if (*dp == '/')
			*dp = '\0';
		    Lst_Init(&temp);
		    Dir_AddDir(&temp, dirpath, NULL);
		    PathMatchFiles(slash+1, &temp, expansions);
		    Lst_Destroy(&temp, NOFREE);
		}
	    } else
		/* Start the search from the local directory.  */
		PathMatchFiles(word, path, expansions);
	    return;
	}
    }
    /* Return the file -- this should never happen.  */
    PathMatchFiles(word, path, expansions);
}

/*-
 *-----------------------------------------------------------------------
 * DirExpandCurly --
 *	Expand curly braces like the C shell, and other wildcards as per
 *	Str_Match.
 *	Note the special behavior: if curly expansion yields a result with
 *	no wildcards, the result is placed on the list WITHOUT CHECKING
 *	FOR ITS EXISTENCE.
 *-----------------------------------------------------------------------
 */
static void
DirExpandCurly(word, path, expansions)
    const char	*word;		/* Entire word to expand */
    Lst 	path;		/* Search path to use */
    Lst 	expansions;	/* Place to store the expansions */
{
    const char	*cp2;		/* Pointer for checking for wildcards in
				 * expansion before calling Dir_Expand */
    LIST	curled; 	/* Queue of words to expand */
    char	*toexpand;	/* Current word to expand */
    Boolean	dowild; 	/* Wildcard left after curlies ? */

    /* Determine once and for all if there is something else going on */
    dowild = FALSE;
    for (cp2 = word; *cp2 != '\0'; cp2++)
	if (*cp2 == '*' || *cp2 == '?' || *cp2 == '[') {
		dowild = TRUE;
		break;
	}

    /* Prime queue with copy of initial word */
    Lst_Init(&curled);
    Lst_EnQueue(&curled, estrdup(word));
    while ((toexpand = (char *)Lst_DeQueue(&curled)) != NULL) {
	const char	*brace;
	const char	*start; /* Start of current chunk of brace clause */
	const char	*end;	/* Character after the closing brace */
	int		bracelevel;
				/* Keep track of nested braces. If we hit
				 * the right brace with bracelevel == 0,
				 * this is the end of the clause. */
	const char	*cp;	/* Current position in brace clause */
	size_t		otherLen;
				/* The length of the non-curlied part of
				 * the current expansion */

	/* End case: no curly left to expand */
	brace = strchr(toexpand, '{');
	if (brace == NULL) {
	    if (dowild) {
		DirExpandWild(toexpand, path, expansions);
		free(toexpand);
	    } else
		Lst_AtEnd(expansions, toexpand);
	}

	start = brace+1;

	/* Find the end of the brace clause first, being wary of nested brace
	 * clauses.  */
	for (end = start, bracelevel = 0;; end++) {
	    if (*end == '{')
		bracelevel++;
	    else if (*end == '\0') {
		Error("Unterminated {} clause \"%s\"", start);
		return;
	    } else if (*end == '}' && bracelevel-- == 0)
		break;
	}
	end++;
	otherLen = brace - toexpand + strlen(end);

	for (cp = start; cp < end; cp++) {
	    char	*file;	/* To hold current expansion */

		/* Find the end of the current expansion */
	    bracelevel = 0;
	    while (*cp != ',') {
		if (*cp == '{')
		    bracelevel++;
		else if (*cp == '}' && bracelevel-- <= 0)
		    break;
		cp++;
	    }
	    /* Build the current combination and enqueue it.  */
	    file = emalloc(otherLen + cp - start + 1);
	    if (brace != toexpand)
		memcpy(file, toexpand, brace-word);
	    if (cp != start)
		memcpy(file+(brace-toexpand), start, cp-start);
	    strcpy(file+(brace-toexpand)+(cp-start), end);
	    Lst_EnQueue(&curled, file);
	}
    }
}

/*-
 *-----------------------------------------------------------------------
 * Dir_Expand  --
 *	Expand the given word into a list of words by globbing it looking
 *	in the directories on the given search path.
 *
 * Results:
 *	A list of words consisting of the files which exist along the search
 *	path matching the given pattern.
 *
 * Side Effects:
 *	Directories may be opened.
 *-----------------------------------------------------------------------
 */
void
Dir_Expand(word, path, expansions)
    const char	*word;		/* the word to expand */
    Lst 	path;		/* the list of directories in which to find
				 * the resulting files */
    Lst 	expansions;	/* the list on which to place the results */
{
    const char	*cp;

    if (DEBUG(DIR))
	printf("expanding \"%s\"...", word);

    cp = strchr(word, '{');
    if (cp)
	DirExpandCurly(word, path, expansions);
    else
	DirExpandWild(word, path, expansions);

    if (DEBUG(DIR)) {
	Lst_Every(expansions, DirPrintWord);
	fputc('\n', stdout);
    }
}

/*-
 *-----------------------------------------------------------------------
 * Dir_FindFilei  --
 *	Find the file with the given name along the given search path.
 *
 * Results:
 *	The path to the file or NULL. This path is guaranteed to be in a
 *	different part of memory than name and so may be safely free'd.
 *
 * Side Effects:
 *	If the file is found in a directory which is not on the path
 *	already (either 'name' is absolute or it is a relative path
 *	[ dir1/.../dirn/file ] which exists below one of the directories
 *	already on the search path), its directory is added to the end
 *	of the path on the assumption that there will be more files in
 *	that directory later on. Sometimes this is true. Sometimes not.
 *-----------------------------------------------------------------------
 */
char *
Dir_FindFilei(name, end, path)
    const char		*name;	/* the file to find */
    const char		*end;	/* end of file name */
    Lst 		path;	/* List of directories to search */
{
    char		*p1;	/* pointer into p->name */
    const char		*p2;	/* pointer into name */
    LstNode		ln;	/* a list element */
    char		*file;	/* the current filename to check */
    char		*temp;	/* index into file */
    Path		*p;	/* current path member */
    const char		*cp;	/* index of first slash, if any */
    Boolean		hasSlash;
    struct stat 	stb;	/* Buffer for stat, if necessary */
    struct file_stamp	*entry; /* Entry for mtimes table */
    u_int32_t		hv;
    char		*q;	/* Copy of name, end */

    /* Find the final component of the name and note whether it has a
     * slash in it (the name, I mean).	*/
    cp = lastchar(name, end, '/');
    if (cp) {
	hasSlash = TRUE;
	cp++;
    } else {
	hasSlash = FALSE;
	cp = name;
    }

    hv = ohash_interval(cp, &end);

    if (DEBUG(DIR))
	printf("Searching for %s...", name);
    /* No matter what, we always look for the file in the current directory
     * before anywhere else and we *do not* add the ./ to it if it exists.
     * This is so there are no conflicts between what the user specifies
     * (fish.c) and what pmake finds (./fish.c).  */
    if ((!hasSlash || (cp - name == 2 && *name == '.')) &&
	find_file_hash(dot, cp, end, hv) != NULL) {
	    if (DEBUG(DIR))
		printf("in '.'\n");
	    hits++;
	    dot->hits++;
	    return interval_dup(name, end);
    }

    /* We look through all the directories on the path seeking one which
     * contains the final component of the given name and whose final
     * component(s) match the name's initial component(s). If such a beast
     * is found, we concatenate the directory name and the final component
     * and return the resulting string. If we don't find any such thing,
     * we go on to phase two...  */
    for (ln = Lst_First(path); ln != NULL; ln = Lst_Adv(ln)) {
	p = (Path *)Lst_Datum(ln);
	if (DEBUG(DIR))
	    printf("%s...", p->name);
	if (find_file_hash(p, cp, end, hv) != NULL) {
	    if (DEBUG(DIR))
		printf("here...");
	    if (hasSlash) {
		/* If the name had a slash, its initial components and p's
		 * final components must match. This is false if a mismatch
		 * is encountered before all of the initial components
		 * have been checked (p2 > name at the end of the loop), or
		 * we matched only part of one of the components of p
		 * along with all the rest of them (*p1 != '/').  */
		p1 = p->name + strlen(p->name) - 1;
		p2 = cp - 2;
		while (p2 >= name && p1 >= p->name && *p1 == *p2) {
		    p1--;
		    p2--;
		}
		if (p2 >= name || (p1 >= p->name && *p1 != '/')) {
		    if (DEBUG(DIR))
			printf("component mismatch -- continuing...");
		    continue;
		}
	    }
	    file = str_concati(p->name, cp, end, '/');
	    if (DEBUG(DIR))
		printf("returning %s\n", file);
	    p->hits++;
	    hits++;
	    return file;
	} else if (hasSlash) {
	    /* If the file has a leading path component and that component
	     * exactly matches the entire name of the current search
	     * directory, we assume the file doesn't exist and return NULL.  */
	    for (p1 = p->name, p2 = name; *p1 && *p1 == *p2; p1++, p2++)
		continue;
	    if (*p1 == '\0' && p2 == cp - 1) {
		if (DEBUG(DIR))
		    printf("has to be here but isn't -- returning NULL\n");
		return NULL;
	    }
	}
    }

    /* We didn't find the file on any existing members of the directory.
     * If the name doesn't contain a slash, that means it doesn't exist.
     * If it *does* contain a slash, however, there is still hope: it
     * could be in a subdirectory of one of the members of the search
     * path. (eg. /usr/include and sys/types.h. The above search would
     * fail to turn up types.h in /usr/include, but it *is* in
     * /usr/include/sys/types.h) If we find such a beast, we assume there
     * will be more (what else can we assume?) and add all but the last
     * component of the resulting name onto the search path (at the
     * end). This phase is only performed if the file is *not* absolute.  */
    if (!hasSlash) {
	if (DEBUG(DIR))
	    printf("failed.\n");
	misses++;
	return NULL;
    }

    if (*name != '/') {
	Boolean checkedDot = FALSE;

	if (DEBUG(DIR))
	    printf("failed. Trying subdirectories...");
	for (ln = Lst_First(path); ln != NULL; ln = Lst_Adv(ln)) {
	    p = (Path *)Lst_Datum(ln);
	    if (p != dot)
		file = str_concati(p->name, name, end, '/');
	    else {
		/* Checking in dot -- DON'T put a leading ./ on the thing.  */
		file = interval_dup(name, end);
		checkedDot = TRUE;
	    }
	    if (DEBUG(DIR))
		printf("checking %s...", file);

	    if (stat(file, &stb) == 0) {
		TIMESTAMP mtime;

		grab_stat(stb, mtime);
		if (DEBUG(DIR))
		    printf("got it.\n");

		/* We've found another directory to search. We know there's
		 * a slash in 'file' because we put one there. We call
		 * Dir_AddDir to add this new directory onto the existing
		 * search path. Once that's done, we return the file name,
		 * knowing that should a file in this directory ever be
		 * referenced again in such a manner, we will find it
		 * without having to do numerous access calls. Hurrah!	*/
		temp = strrchr(file, '/');
		Dir_AddDir(path, file, temp);

		/* Save the modification time so if it's needed, we don't have
		 * to fetch it again.  */
		if (DEBUG(DIR))
		    printf("Caching %s for %s\n", Targ_FmtTime(mtime),
			    file);
		record_stamp(file, mtime);
		nearmisses++;
		return file;
	    } else
		free(file);
	}

	if (DEBUG(DIR))
	    printf("failed. ");

	if (checkedDot) {
	    /* Already checked by the given name, since . was in the path,
	     * so no point in proceeding...  */
	    if (DEBUG(DIR))
		printf("Checked . already, returning NULL\n");
	    return NULL;
	}
    }

    /* Didn't find it that way, either. Sigh. Phase 3. Add its directory
     * onto the search path in any case, just in case, then look for the
     * thing in the hash table. If we find it, grand. We return a new
     * copy of the name. Otherwise we sadly return a NULL pointer. Sigh.
     * Note that if the directory holding the file doesn't exist, this will
     * do an extra search of the final directory on the path. Unless something
     * weird happens, this search won't succeed and life will be groovy.
     *
     * Sigh. We cannot add the directory onto the search path because
     * of this amusing case:
     * $(INSTALLDIR)/$(FILE): $(FILE)
     *
     * $(FILE) exists in $(INSTALLDIR) but not in the current one.
     * When searching for $(FILE), we will find it in $(INSTALLDIR)
     * b/c we added it here. This is not good...  */
#ifdef notdef
    Dir_AddDir(path, name, cp-1);

    bigmisses += 1;
    ln = Lst_Last(path);
    if (ln == NULL)
	return NULL;
    else
	p = (Path *)Lst_Datum(ln);

    if (find_file_hash(p, cp, e, hv) != NULL)
	return estrdup(name);
    else
	return NULL;
#else /* !notdef */
    q = interval_dup(name, end);
    if (DEBUG(DIR))
	printf("Looking for \"%s\"...", q);

    bigmisses++;
    entry = find_stampi(name, end);
    if (entry != NULL) {
	if (DEBUG(DIR))
	    printf("got it (in mtime cache)\n");
	return q;
    } else if (stat(q, &stb) == 0) {
	TIMESTAMP mtime;

	grab_stat(stb, mtime);
	if (DEBUG(DIR))
	    printf("Caching %s for %s\n", Targ_FmtTime(mtime),
		    q);
	record_stamp(q, mtime);
	return q;
    } else {
	if (DEBUG(DIR))
	    printf("failed. Returning NULL\n");
	free(q);
	return NULL;
    }
#endif /* notdef */
}

/*-
 *-----------------------------------------------------------------------
 * Dir_MTime  --
 *	Find the modification time of the file described by gn along the
 *	search path dirSearchPath.
 *
 * Results:
 *	The modification time or OUT_OF_DATE if it doesn't exist
 *
 * Side Effects:
 *	The modification time is placed in the node's mtime slot.
 *	If the node didn't have a path entry before, and Dir_FindFile
 *	found one for it, the full name is placed in the path slot.
 *-----------------------------------------------------------------------
 */
TIMESTAMP
Dir_MTime(gn)
    GNode	  *gn;	      /* the file whose modification time is
			       * desired */
{
    char	  *fullName;  /* the full pathname of name */
    struct stat   stb;	      /* buffer for finding the mod time */
    struct file_stamp
		  *entry;
    unsigned int  slot;
    TIMESTAMP	  mtime;

    if (gn->type & OP_ARCHV)
	return Arch_MTime(gn);

    if (gn->path == NULL) {
	fullName = Dir_FindFile(gn->name, &dirSearchPath);
	if (fullName == NULL)
	    fullName = estrdup(gn->name);
    } else
	fullName = gn->path;

    slot = ohash_qlookup(&mtimes, fullName);
    entry = ohash_find(&mtimes, slot);
    if (entry != NULL) {
	/* Only do this once -- the second time folks are checking to
	 * see if the file was actually updated, so we need to actually go
	 * to the file system.	*/
	if (DEBUG(DIR))
	    printf("Using cached time %s for %s\n",
		    Targ_FmtTime(entry->mtime), fullName);
	mtime = entry->mtime;
	free(entry);
	ohash_remove(&mtimes, slot);
    } else if (stat(fullName, &stb) == 0)
	grab_stat(stb, mtime);
    else {
	if (gn->type & OP_MEMBER) {
	    if (fullName != gn->path)
		free(fullName);
	    return Arch_MemMTime(gn);
	} else
	    set_out_of_date(mtime);
    }
    if (fullName && gn->path == NULL)
	gn->path = fullName;

    gn->mtime = mtime;
    return gn->mtime;
}

/* Read a directory, either from the disk, or from the cache.  */
static Path *
DirReaddir(name, end)
    const char		*name;
    const char		*end;
{
    Path		*p;	/* pointer to new Path structure */
    DIR 		*d;	/* for reading directory */
    struct dirent	*dp;	/* entry in directory */
    unsigned int	slot;

    slot = ohash_qlookupi(&openDirectories, name, &end);
    p = ohash_find(&openDirectories, slot);

    if (p != NULL)
	return p;

    p = ohash_create_entry(&dir_info, name, &end);
    p->hits = 0;
    p->refCount = 0;
    ohash_init(&p->files, 4, &file_info);

    if (DEBUG(DIR)) {
	printf("Caching %s...", p->name);
	fflush(stdout);
    }

    if ((d = opendir(p->name)) == NULL)
	return NULL;
    /* Skip the first two entries -- these will *always* be . and ..  */
    (void)readdir(d);
    (void)readdir(d);

    while ((dp = readdir(d)) != NULL) {
#if defined(sun) && defined(d_ino) /* d_ino is a sunos4 #define for d_fileno */
	/* The sun directory library doesn't check for a 0 inode
	 * (0-inode slots just take up space), so we have to do
	 * it ourselves.  */
	if (dp->d_fileno == 0)
	    continue;
#endif /* sun && d_ino */
	add_file(p, dp->d_name);
    }
    (void)closedir(d);
    if (DEBUG(DIR))
	printf("done\n");

    ohash_insert(&openDirectories, slot, p);
    return p;
}

/*-
 *-----------------------------------------------------------------------
 * Dir_AddDir --
 *	Add the given name to the end of the given path. The order of
 *	the arguments is backwards so ParseDoDependency can do a
 *	Lst_ForEach of its list of paths...
 *
 * Side Effects:
 *	A structure is added to the list and the directory is
 *	read and hashed.
 *-----------------------------------------------------------------------
 */

void
Dir_AddDir(path, name, end)
    Lst 	path;	/* the path to which the directory should be added */
    const char	*name;	/* the name of the directory to add */
    const char	*end;
{
    Path	*p;	/* pointer to new Path structure */

    p = DirReaddir(name, end);
    if (p == NULL)
	return;
    if (p->refCount == 0)
	Lst_AtEnd(path, p);
    else if (Lst_AddNew(path, p) == FAILURE)
	return;
    p->refCount++;
}

/*-
 *-----------------------------------------------------------------------
 * Dir_CopyDir --
 *	Callback function for duplicating a search path via Lst_Duplicate.
 *	Ups the reference count for the directory.
 *
 * Results:
 *	Returns the Path it was given.
 *
 * Side Effects:
 *	The refCount of the path is incremented.
 *-----------------------------------------------------------------------
 */
void *
Dir_CopyDir(p)
    void *p;
{
    ((Path *)p)->refCount++;
    return p;
}

/*-
 *-----------------------------------------------------------------------
 * Dir_MakeFlags --
 *	Make a string by taking all the directories in the given search
 *	path and preceding them by the given flag. Used by the suffix
 *	module to create variables for compilers based on suffix search
 *	paths.
 *
 * Results:
 *	The string mentioned above. Note that there is no space between
 *	the given flag and each directory. The empty string is returned if
 *	Things don't go well.
 *-----------------------------------------------------------------------
 */
char *
Dir_MakeFlags(flag, path)
    const char	  *flag;  /* flag which should precede each directory */
    Lst 	  path;   /* list of directories */
{
    LstNode	  ln;	  /* the node of the current directory */
    BUFFER	  buf;

    Buf_Init(&buf, 0);

    for (ln = Lst_First(path); ln != NULL; ln = Lst_Adv(ln)) {
	    Buf_AddString(&buf, flag);
	    Buf_AddString(&buf, ((Path *)Lst_Datum(ln))->name);
	    Buf_AddSpace(&buf);
    }

    return Buf_Retrieve(&buf);
}

/*-
 *-----------------------------------------------------------------------
 * Dir_Destroy --
 *	Nuke a directory descriptor, if possible. Callback procedure
 *	for the suffixes module when destroying a search path.
 *
 * Side Effects:
 *	If no other path references this directory (refCount == 0),
 *	the Path and all its data are freed.
 *-----------------------------------------------------------------------
 */
void
Dir_Destroy(pp)
    void	*pp;		/* The directory descriptor to nuke */
{
    Path	*p = (Path *)pp;

    if (--p->refCount == 0) {
	ohash_remove(&openDirectories, ohash_qlookup(&openDirectories, p->name));
	free_hash(&p->files);
	free(p);
    }
}

/*-
 *-----------------------------------------------------------------------
 * Dir_Concat --
 *	Concatenate two paths, adding the second to the end of the first.
 *	Makes sure to avoid duplicates.
 *
 * Side Effects:
 *	Reference counts for added dirs are upped.
 *-----------------------------------------------------------------------
 */
void
Dir_Concat(path1, path2)
    Lst 	path1;		/* Dest */
    Lst 	path2;		/* Source */
{
    LstNode	ln;
    Path	*p;

    for (ln = Lst_First(path2); ln != NULL; ln = Lst_Adv(ln)) {
	p = (Path *)Lst_Datum(ln);
	if (Lst_AddNew(path1, p) == SUCCESS)
	    p->refCount++;
    }
}

/********** DEBUG INFO **********/
void
Dir_PrintDirectories()
{
    Path		*p;
    unsigned int	i;

    printf("#*** Directory Cache:\n");
    printf("# Stats: %d hits %d misses %d near misses %d losers (%d%%)\n",
	      hits, misses, nearmisses, bigmisses,
	      (hits+bigmisses+nearmisses ?
	       hits * 100 / (hits + bigmisses + nearmisses) : 0));
    printf("# %-20s referenced\thits\n", "directory");
    for (p = ohash_first(&openDirectories, &i); p != NULL;
	p = ohash_next(&openDirectories, &i))
	    printf("# %-20s %10d\t%4d\n", p->name, p->refCount, p->hits);
}

static void
DirPrintDir(p)
    void	*p;
{
    printf("%s ", ((Path *)p)->name);
}

void
Dir_PrintPath(path)
    Lst path;
{
    Lst_Every(path, DirPrintDir);
}

#ifndef USE_TIMESPEC
#include <sys/types.h>
#include <utime.h>
#endif
int
set_times(f)
    const char *f;
{
#ifdef USE_TIMESPEC
    struct timeval tv[2];

    TIMESPEC_TO_TIMEVAL(&tv[0], &now);
    TIMESPEC_TO_TIMEVAL(&tv[1], &now);
    return utimes(f, tv);
#else
    struct utimbuf times;

    times.actime = times.modtime = now;
    return utime(f, &times);
#endif
}