/************************************************************************
 * This program is Copyright (C) 1986 by Jonathan Payne.  JOVE is	*
 * provided to you without charge, and with no warranty.  You may give	*
 * away copies of JOVE, including sources, provided that this notice is *
 * included in all the files.						*
 ************************************************************************/
/*
 * for a non-unix system, you have to supply the sys/dir.h include file
 * which defines DIR and DIRSIZE(DIR *entry),
 * and the opendir, closedir, and readdir routines.
 * See "readdir.h" for all the gory details.
 */

#include "jove.h"

#ifdef F_COMPLETION

RCS("$Id: scandir.c,v 14.31 1993/02/17 01:24:19 tom Exp tom $")

#define READDIR_IMPLEMENTATION	/* to resolve system-dependencies */
#include "readdir.h"

private char **resize __(( char **_(base), int _(n) ));
private char **
resize(base, n)
register char	**base;
int		n;
{
	if ((base = (char **) realloc((char *) base, n * sizeof(char *))) == NULL)
		complain("[out of memory]");
	return base;
}

/* Scandir returns the number of entries or -1 if the directory cannot
   be opened; complains if malloc fails. */

#define CHUNKSIZE	32

int
scandir(dir, nmptr, qualify, sorter)
const char	*dir;
register char	***nmptr;
int		(*qualify)__(( const char *_(name) ));
int		(*sorter)__(( const char **_(a), const char **_(b) ));
{
	register size_t		nent = 0;
	register struct dirent	*ent;	/* old compilers don't like "entry" */
	register DIR		*dirp;
	register size_t		nalloc = CHUNKSIZE;
	register int		len;
#if !pdp11
	/* for error recovery; not needed for compilers that unwind the stack
	   and restore registers on longjmp. (like pdp11 7th Ed. cc) */
	volatile union {int i;}	_nent;
#   define v_nent	_nent.i
#endif

	if ((dirp = opendir(dir)) == NULL)
		return -1;

    CATCH
	(*nmptr) = NULL;
	(*nmptr) = (char **) emalloc(CHUNKSIZE * sizeof (char *));

	while (ent = readdir(dirp)) {
		if (qualify && !(*qualify)(ent->d_name))
			continue;
#ifdef v_nent
		v_nent = nent;
#endif
		if (nent == nalloc)
			(*nmptr) = resize((*nmptr), nalloc += CHUNKSIZE);

		len = DIRSIZE(ent);
		null_ncpy((*nmptr)[nent] = emalloc(len + 1), ent->d_name, len);
		nent++;
	}

	(*nmptr) = resize((*nmptr), nent + 1);
	(*nmptr)[nent] = NULL;			/* guaranteed 0 pointer */

	if (sorter)
		qsort((*nmptr), nent, sizeof(char **),
		      (int (*)__(( const void *, const void * ))) sorter);
				/* Yuck! */
    ONERROR

#ifndef v_nent
#   define v_nent	nent
#endif
	if (*nmptr)
		freedir(nmptr, v_nent);

	nent = -1;

    ENDCATCH

	closedir(dirp);

#undef v_nent

	return nent;
}

void
freedir(nmptr, nent)
register char	***nmptr;
int		nent;
{
	register char	**base = *nmptr;

	while (--nent >= 0)
		free(*base++);
	free((void_*) *nmptr);
	*nmptr = NULL;
}

int
alphacomp(a, b)
const char	**a,
		**b;
{
	return strcmp(*a, *b);
}

#endif /* F_COMPLETION */

/*======================================================================
 * $Log: scandir.c,v $
 * Revision 14.31  1993/02/17  01:24:19  tom
 * fix longjmp register botch in scandir().
 *
 * Revision 14.30  1993/01/29  13:53:51  tom
 * cleanup whitespace; some random optimizations.
 *
 * Revision 14.28  1992/10/24  01:24:22  tom
 * convert to "port{ansi,defs}.h" conventions.
 *
 * Revision 14.26  1992/08/26  23:56:58  tom
 * Posix-ate (direct => dirent); add RCS directives.
 *
 */