/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2009, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1986-2011, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Ken Stevens, Steve McClure, Markus Armbruster
*
- * This program is free software; you can redistribute it and/or modify
+ * Empire is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* ---
*
* Known contributors to this file:
* Dave Pare, 1989
* Steve McClure, 2000
- * Markus Armbruster, 2005-2008
+ * Markus Armbruster, 2005-2009
*/
#include <config.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
+#ifdef _WIN32
+#include <io.h>
+#include <share.h>
+#endif
#include "file.h"
#include "match.h"
#include "misc.h"
#include "nsc.h"
#include "prototypes.h"
+static int open_locked(char *, int, mode_t);
static int ef_realloc_cache(struct empfile *, int);
static int fillcache(struct empfile *, int);
static int do_read(struct empfile *, void *, int, int);
static int do_write(struct empfile *, void *, int, int);
static unsigned get_seqno(struct empfile *, int);
static void new_seqno(struct empfile *, void *);
+static void must_be_fresh(struct empfile *, void *);
static void do_blank(struct empfile *, void *, int, int);
static int ef_check(int);
+static unsigned ef_generation;
+
/*
* Open the file-backed table TYPE (EF_SECTOR, ...).
* HOW are flags to control operation. Naturally, immutable flags are
ef_open(int type, int how, int nelt)
{
struct empfile *ep;
- struct flock lock;
int oflags, fd, fsiz, nslots;
if (ef_check(type) < 0)
oflags = O_RDONLY;
if (how & EFF_CREATE)
oflags |= O_CREAT | O_TRUNC;
-#if defined(_WIN32)
- oflags |= O_BINARY;
-#endif
- fd = open(ep->file, oflags, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ fd = open_locked(ep->file, oflags, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
if (fd < 0) {
logerror("Can't open %s (%s)", ep->file, strerror(errno));
return 0;
}
- lock.l_type = how & EFF_PRIVATE ? F_RDLCK : F_WRLCK;
- lock.l_whence = SEEK_SET;
- lock.l_start = lock.l_len = 0;
- if (fcntl(fd, F_SETLK, &lock) == -1) {
- logerror("Can't lock %s (%s)", ep->file, strerror(errno));
- close(fd);
- return 0;
- }
-
/* get file size */
fsiz = fsize(fd);
if (fsiz % ep->size) {
return 1;
}
+static int
+open_locked(char *name, int oflags, mode_t mode)
+{
+ int rdlonly = (oflags & O_ACCMODE) == O_RDONLY;
+ int fd;
+
+#ifdef _WIN32
+ fd = _sopen(name, oflags | O_BINARY, rdlonly ? SH_DENYNO : SH_DENYWR,
+ mode);
+ if (fd < 0)
+ return -1;
+#else /* !_WIN32 */
+ struct flock lock;
+
+ fd = open(name, oflags, mode);
+ if (fd < 0)
+ return -1;
+
+ lock.l_type = rdlonly ? F_RDLCK : F_WRLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = lock.l_len = 0;
+ if (fcntl(fd, F_SETLK, &lock) == -1) {
+ close(fd);
+ return -1;
+ }
+#endif /* !_WIN32 */
+ return fd;
+}
+
/*
* Reallocate cache for table EP to hold COUNT slots.
* The table must not be allocated statically.
cachep = ep->cache + (id - ep->baseid) * ep->size;
}
memcpy(into, cachep, ep->size);
+ ef_mark_fresh(type, into);
if (ep->postread)
ep->postread(id, into);
if (ep->onresize && ep->onresize(type) < 0)
return 0;
}
- if (id >= ep->baseid && id < ep->baseid + ep->cids)
+ if (id >= ep->baseid && id < ep->baseid + ep->cids) {
cachep = ep->cache + (id - ep->baseid) * ep->size;
- else
+ if (cachep != from)
+ must_be_fresh(ep, from);
+ } else
cachep = NULL;
if (ep->prewrite)
ep->prewrite(id, cachep, from);
if (!(ep->flags & EFF_TYPED))
return;
old_seqno = get_seqno(ep, elt->uid);
- if (CANT_HAPPEN(old_seqno != elt->seqno))
- old_seqno = MAX(old_seqno, elt->seqno);
+ CANT_HAPPEN(old_seqno != elt->seqno);
elt->seqno = old_seqno + 1;
}
+void
+ef_make_stale(void)
+{
+ ef_generation++;
+}
+
+void
+ef_mark_fresh(int type, void *buf)
+{
+ struct empfile *ep;
+
+ if (ef_check(type) < 0)
+ return;
+ ep = &empfile[type];
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ ((struct emptypedstr *)buf)->generation = ef_generation;
+}
+
+static void
+must_be_fresh(struct empfile *ep, void *buf)
+{
+ struct emptypedstr *elt = buf;
+
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ CANT_HAPPEN(elt->generation != (ef_generation & 0xfff));
+}
+
/*
* Extend table TYPE by COUNT elements.
* Any pointers obtained from ef_ptr() become invalid.
elt = buf;
elt->seqno = get_seqno(ep, elt->uid);
}
+ ef_mark_fresh(type, buf);
}
/*
projects / empserver / blobdiff