freebsd-nq/libexec/ypxfr/yp_dbwrite.c
Bill Paul d6cab90261 Sync with my sources at home (these are really tiny changes):
- Fix a SEGV condition in ypxfr_main.c that reared its ugly head while I
  was working on the 'parallel jobs' feature of the new yppush. After we've
  completed the map transfer and created a local temporary copy, we check
  the order number of the map on ypserv again to make sure it didn't change
  while the transfer was in progress (map skew). If for some reason we flat
  out fail to get the order number from the server, we flag this as an
  error and bail, telling ypxfr_exit() to clean up our temporary files
  for us. However, ypxfr_exit() tries to close the database before unkining
  it, not realizing that it has already been closed prior to the skew check.
  The second attempt to close the database causes a SEGV somewhere inside
  the DB code.

  (Well, it does on my 2.0.5 machine anyway. I haven't seen anyone modify
  the DB library code in ages, so the condition is probably still there.)

  To work around this, we deliberately set dbp to NULL after closing the
  database and check for the condition in ypxfr_exit(), being careful to
  avoid the second close if we see the NULL.

- In yp_dbwrite.c, make yp_open_db_rw() open the database with O_EXLOCK
  flag set. This probably won't affect much of anything, but I feel better
  having it there.
1996-01-06 20:28:06 +00:00

106 lines
2.9 KiB
C

/*
* Copyright (c) 1995
* Bill Paul <wpaul@ctr.columbia.edu>. 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 Bill Paul.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul 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.
*
* $Id: yp_dbwrite.c,v 1.1.1.1 1995/12/25 03:07:13 wpaul Exp $
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <limits.h>
#include <unistd.h>
#include <db.h>
#include <sys/stat.h>
#include <errno.h>
#include <paths.h>
#include "yp.h"
#include "ypxfr_extern.h"
#ifndef lint
static const char rcsid[] = "$Id: yp_dbwrite.c,v 1.1.1.1 1995/12/25 03:07:13 wpaul Exp $";
#endif
#define PERM_SECURE (S_IRUSR|S_IWUSR)
/*
* Open a DB database read/write
*/
DB *yp_open_db_rw(domain, map)
const char *domain;
const char *map;
{
DB *dbp;
char buf[1025];
yp_errno = YP_TRUE;
if (map[0] == '.' || strchr(map, '/')) {
yp_errno = YP_BADARGS;
return (NULL);
}
snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, domain, map);
dbp = dbopen(buf,O_RDWR|O_EXLOCK|O_EXCL|O_CREAT, PERM_SECURE, DB_HASH, &openinfo);
if (dbp == NULL) {
switch(errno) {
case ENOENT:
yp_errno = YP_NOMAP;
break;
case EFTYPE:
yp_errno = YP_BADDB;
break;
default:
yp_errno = YP_YPERR;
break;
}
}
return (dbp);
}
int yp_put_record(dbp,key,data)
DB *dbp;
DBT *key;
DBT *data;
{
if ((dbp->put)(dbp,key,data,0)) {
(void)(dbp->close)(dbp);
return(YP_BADDB);
}
return(YP_TRUE);
}