diff options
Diffstat (limited to 'lib/libc/gen/telldir.c')
| -rw-r--r-- | lib/libc/gen/telldir.c | 157 |
1 files changed, 0 insertions, 157 deletions
diff --git a/lib/libc/gen/telldir.c b/lib/libc/gen/telldir.c deleted file mode 100644 index ab23d9d..0000000 --- a/lib/libc/gen/telldir.c +++ /dev/null @@ -1,157 +0,0 @@ -/* - * Copyright (c) 1983, 1993 - * The Regents of the University of California. All rights reserved. - * - * 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. - */ - -#if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "@(#)telldir.c 8.1 (Berkeley) 6/4/93"; -#endif /* LIBC_SCCS and not lint */ - -#include <sys/param.h> -#include <dirent.h> -#include <stdlib.h> -#include <unistd.h> - -/* - * The option SINGLEUSE may be defined to say that a telldir - * cookie may be used only once before it is freed. This option - * is used to avoid having memory usage grow without bound. - */ -#define SINGLEUSE - -/* - * One of these structures is malloced to describe the current directory - * position each time telldir is called. It records the current magic - * cookie returned by getdirentries and the offset within the buffer - * associated with that return value. - */ -struct ddloc { - struct ddloc *loc_next;/* next structure in list */ - long loc_index; /* key associated with structure */ - long loc_seek; /* magic cookie returned by getdirentries */ - long loc_loc; /* offset of entry in buffer */ - const DIR* loc_dirp; /* directory which used this entry */ -}; - -#define NDIRHASH 32 /* Num of hash lists, must be a power of 2 */ -#define LOCHASH(i) ((i)&(NDIRHASH-1)) - -static long dd_loccnt; /* Index of entry for sequential readdir's */ -static struct ddloc *dd_hash[NDIRHASH]; /* Hash list heads for ddlocs */ - -/* - * return a pointer into a directory - */ -long -telldir(dirp) - const DIR *dirp; -{ - register int index; - register struct ddloc *lp; - - if ((lp = (struct ddloc *)malloc(sizeof(struct ddloc))) == NULL) - return (-1); - index = dd_loccnt++; - lp->loc_index = index; - lp->loc_seek = dirp->dd_seek; - lp->loc_loc = dirp->dd_loc; - lp->loc_dirp = dirp; - lp->loc_next = dd_hash[LOCHASH(index)]; - dd_hash[LOCHASH(index)] = lp; - return (index); -} - -/* - * seek to an entry in a directory. - * Only values returned by "telldir" should be passed to seekdir. - */ -void -_seekdir(dirp, loc) - register DIR *dirp; - long loc; -{ - register struct ddloc *lp; - register struct ddloc **prevlp; - struct dirent *dp; - - prevlp = &dd_hash[LOCHASH(loc)]; - lp = *prevlp; - while (lp != NULL) { - if (lp->loc_index == loc) - break; - prevlp = &lp->loc_next; - lp = lp->loc_next; - } - if (lp == NULL) - return; - if (lp->loc_loc == dirp->dd_loc && lp->loc_seek == dirp->dd_seek) - goto found; - (void) lseek(dirp->dd_fd, (off_t)lp->loc_seek, SEEK_SET); - dirp->dd_seek = lp->loc_seek; - dirp->dd_loc = 0; - while (dirp->dd_loc < lp->loc_loc) { - dp = readdir(dirp); - if (dp == NULL) - break; - } -found: -#ifdef SINGLEUSE - *prevlp = lp->loc_next; - free((caddr_t)lp); -#endif -} - -/* - * Reclaim memory for telldir cookies which weren't used. - */ -void -_reclaim_telldir(dirp) - register const DIR *dirp; -{ - register struct ddloc *lp; - register struct ddloc **prevlp; - int i; - - for (i = 0; i < NDIRHASH; i++) { - prevlp = &dd_hash[i]; - lp = *prevlp; - while (lp != NULL) { - if (lp->loc_dirp == dirp) { - *prevlp = lp->loc_next; - free((caddr_t)lp); - lp = *prevlp; - continue; - } - prevlp = &lp->loc_next; - lp = lp->loc_next; - } - } -} |
