/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2007, 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/>.
*
* ---
*
* ---
*
* file.c: Operations on Empire tables (`files' for historical reasons)
- *
+ *
* Known contributors to this file:
* Dave Pare, 1989
* Steve McClure, 2000
- * Markus Armbruster, 2005-2006
+ * Markus Armbruster, 2005-2011
*/
#include <config.h>
#include <errno.h>
-#if defined(_WIN32)
-#include <io.h>
-#include <share.h>
-#endif
#include <fcntl.h>
#include <sys/stat.h>
-#include <signal.h>
#include <sys/types.h>
-#if !defined(_WIN32)
#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 "optlist.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
* not permitted.
+ * If NELT is non-negative, the table must have that many elements.
* Return non-zero on success, zero on failure.
* You must call ef_close() before the next ef_open().
*/
int
-ef_open(int type, int how)
+ef_open(int type, int how, int nelt)
{
struct empfile *ep;
-#if !defined(_WIN32)
- struct flock lock;
-#endif
- int oflags, fd, fsiz, size;
+ int oflags, fd, fsiz, fids, nslots;
if (ef_check(type) < 0)
return 0;
/* open file */
ep = &empfile[type];
- if (CANT_HAPPEN(ep->fd >= 0))
+ if (CANT_HAPPEN(!ep->file || ep->base != EF_BAD || ep->fd >= 0))
return 0;
oflags = O_RDWR;
- if (how & EFF_RDONLY)
+ if (how & EFF_PRIVATE)
oflags = O_RDONLY;
if (how & EFF_CREATE)
oflags |= O_CREAT | O_TRUNC;
-#if defined(_WIN32)
- oflags |= O_BINARY;
- if ((fd = sopen(ep->file, oflags,
- how & EFF_RDONLY ? SH_DENYNO : SH_DENYWR,
- S_IRWUG)) < 0) {
- logerror("Can't open %s (%s)", ep->file, strerror(errno));
- return 0;
- }
-#else
- if ((fd = open(ep->file, oflags, S_IRWUG)) < 0) {
+ 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_RDONLY ? 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));
- return 0;
- }
-#endif
-
/* get file size */
fsiz = fsize(fd);
if (fsiz % ep->size) {
close(fd);
return 0;
}
- ep->fids = fsiz / ep->size;
+ fids = fsiz / ep->size;
+ if (nelt >= 0 && nelt != fids) {
+ logerror("Can't open %s (got %d records instead of %d)",
+ ep->file, fids, nelt);
+ close(fd);
+ return 0;
+ }
/* allocate cache */
if (ep->flags & EFF_STATIC) {
/* ep->cache already points to space for ep->csize elements */
if (how & EFF_MEM) {
- if (ep->fids > ep->csize) {
- logerror("Can't open %s: file larger than %d bytes",
- ep->file, ep->fids * ep->size);
+ if (fids > ep->csize) {
+ logerror("Can't open %s (file larger than %d records)",
+ ep->file, ep->csize);
close(fd);
return 0;
}
}
} else {
- if (how & EFF_MEM)
- ep->csize = ep->fids;
- else
- ep->csize = blksize(fd) / ep->size;
- /* 0 could lead to null cache, which confuses assertions */
- if (!ep->csize)
- ep->csize++;
- size = ep->csize * ep->size;
if (CANT_HAPPEN(ep->cache))
free(ep->cache);
- ep->cache = malloc(size);
- if (ep->cache == NULL) {
- logerror("Can't open %s: out of memory", ep->file);
+ if (how & EFF_MEM)
+ nslots = fids;
+ else
+ nslots = blksize(fd) / ep->size;
+ if (!ef_realloc_cache(ep, nslots)) {
+ logerror("Can't map %s (%s)", ep->file, strerror(errno));
close(fd);
return 0;
}
}
ep->baseid = 0;
ep->cids = 0;
+ ep->fids = fids;
ep->flags = (ep->flags & EFF_IMMUTABLE) | (how & ~EFF_CREATE);
ep->fd = fd;
/* map file into cache */
- if ((how & EFF_MEM) && ep->fids) {
- if (fillcache(ep, 0) != ep->fids) {
+ if ((how & EFF_MEM) && fids) {
+ if (fillcache(ep, 0) != fids) {
ep->cids = 0; /* prevent cache flush */
- ep->flags &= EFF_IMMUTABLE; /* maintain invariant */
ef_close(type);
return 0;
}
}
+ if (ep->onresize)
+ ep->onresize(type);
+ 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.
+ * The cache may still be unmapped.
+ * If reallocation succeeds, any pointers obtained from ef_ptr()
+ * become invalid.
+ * If it fails, the cache is unchanged, and errno is set.
+ * Return non-zero on success, zero on failure.
+ */
+static int
+ef_realloc_cache(struct empfile *ep, int count)
+{
+ void *cache;
+
+ if (CANT_HAPPEN(ep->flags & EFF_STATIC))
+ return 0;
+ if (CANT_HAPPEN(count < 0))
+ count = 0;
+
/*
- * Could close fd if both EFF_RDONLY and EFF_MEM, but that doesn't
- * happen, so don't bother.
+ * Avoid zero slots, because that can lead to null cache, which
+ * would be interpreted as unmapped cache.
*/
+ if (count == 0)
+ count++;
+ cache = realloc(ep->cache, count * ep->size);
+ if (!cache)
+ return 0;
+ ep->cache = cache;
+ ep->csize = count;
return 1;
}
/*
- * Close the file-backed table TYPE (EF_SECTOR, ...).
+ * Open the table TYPE, which is a view of a base table
+ * The table must not be already open.
+ * Return non-zero on success, zero on failure.
+ * Beware: views work only as long as the base table doesn't change size!
+ * You must close the view before closing its base table.
+ */
+int
+ef_open_view(int type)
+{
+ struct empfile *ep;
+ int base;
+
+ if (ef_check(type) < 0)
+ return 0;
+ ep = &empfile[type];
+ base = ep->base;
+ if (ef_check(base) < 0)
+ return 0;
+ if (CANT_HAPPEN(!(ef_flags(base) & EFF_MEM)
+ || ep->file || ep->size != empfile[base].size
+ || ep->cache || ep->oninit || ep->postread
+ || ep->prewrite || ep->onresize))
+ return -1;
+
+ ep->cache = empfile[base].cache;
+ ep->csize = empfile[base].csize;
+ ep->flags |= EFF_MEM;
+ ep->baseid = empfile[base].baseid;
+ ep->cids = empfile[base].cids;
+ ep->fids = empfile[base].fids;
+ return 0;
+}
+
+/*
+ * Close the open table TYPE (EF_SECTOR, ...).
* Return non-zero on success, zero on failure.
*/
int
ef_close(int type)
{
struct empfile *ep;
- int retval;
+ int retval = 1;
- retval = ef_flush(type);
+ if (ef_check(type) < 0)
+ return 0;
ep = &empfile[type];
- ep->flags &= EFF_IMMUTABLE;
- if (!(ep->flags & EFF_STATIC)) {
- free(ep->cache);
+
+ if (EF_IS_VIEW(type)) {
ep->cache = NULL;
+ ep->csize = 0;
+ } else {
+ if (!ef_flush(type))
+ retval = 0;
+ if (!(ep->flags & EFF_STATIC)) {
+ free(ep->cache);
+ ep->cache = NULL;
+ ep->csize = 0;
+ }
+ if (close(ep->fd) < 0) {
+ logerror("Error closing %s (%s)", ep->file, strerror(errno));
+ retval = 0;
+ }
+ ep->fd = -1;
}
- if (close(ep->fd) < 0) {
- logerror("Error closing %s (%s)", ep->name, strerror(errno));
- retval = 0;
- }
- ep->fd = -1;
+ ep->flags &= EFF_IMMUTABLE;
+ ep->baseid = ep->cids = ep->fids = 0;
+ if (ep->onresize)
+ ep->onresize(type);
return retval;
}
/*
- * Flush file-backed table TYPE (EF_SECTOR, ...) to disk.
+ * Flush file-backed table TYPE (EF_SECTOR, ...) to its backing file.
+ * Do nothing if the table is privately mapped.
+ * Update timestamps of written elements if table is EFF_TYPED.
* Return non-zero on success, zero on failure.
*/
int
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
+ if (ep->flags & EFF_PRIVATE)
+ return 1; /* nothing to do */
if (CANT_HAPPEN(ep->fd < 0))
return 0;
/*
* allowed only with EFF_MEM. Assume the whole cash is dirty
* then.
*/
- if (!(ep->flags & EFF_RDONLY) && (ep->flags & EFF_MEM))
- return do_write(ep, ep->cache, ep->baseid, ep->cids) >= 0;
+ if (ep->flags & EFF_MEM) {
+ if (do_write(ep, ep->cache, ep->baseid, ep->cids) < 0)
+ return 0;
+ }
return 1;
}
/*
* Read element ID from table TYPE into buffer INTO.
* FIXME pass buffer size!
+ * INTO is marked fresh with ef_mark_fresh().
* Return non-zero on success, zero on failure.
*/
int
ef_read(int type, int id, void *into)
{
struct empfile *ep;
- void *from;
+ void *cachep;
if (ef_check(type) < 0)
return 0;
return 0;
if (ep->flags & EFF_MEM) {
- from = ep->cache + id * ep->size;
+ cachep = ep->cache + id * ep->size;
} else {
if (ep->baseid + ep->cids <= id || ep->baseid > id) {
if (fillcache(ep, id) < 1)
return 0;
}
- from = ep->cache + (id - ep->baseid) * ep->size;
+ cachep = ep->cache + (id - ep->baseid) * ep->size;
}
- memcpy(into, from, ep->size);
+ memcpy(into, cachep, ep->size);
+ ef_mark_fresh(type, into);
if (ep->postread)
ep->postread(id, into);
}
/*
- * Fill cache of EP with elements starting at ID.
+ * Fill cache of file-backed EP with elements starting at ID.
* If any were read, return their number.
* Else return -1 and leave the cache unchanged.
*/
static int
-fillcache(struct empfile *ep, int start)
+fillcache(struct empfile *ep, int id)
+{
+ int ret;
+
+ if (CANT_HAPPEN(!ep->cache))
+ return -1;
+
+ ret = do_read(ep, ep->cache, id, MIN(ep->csize, ep->fids - id));
+ if (ret >= 0) {
+ /* cache changed */
+ ep->baseid = id;
+ ep->cids = ret;
+ }
+ return ret;
+}
+
+static int
+do_read(struct empfile *ep, void *buf, int id, int count)
{
int n, ret;
char *p;
- if (CANT_HAPPEN(ep->fd < 0 || !ep->cache))
+ if (CANT_HAPPEN(ep->fd < 0 || id < 0 || count < 0))
return -1;
- if (lseek(ep->fd, start * ep->size, SEEK_SET) == (off_t)-1) {
- logerror("Error seeking %s (%s)", ep->file, strerror(errno));
+ if (lseek(ep->fd, id * ep->size, SEEK_SET) == (off_t)-1) {
+ logerror("Error seeking %s to elt %d (%s)",
+ ep->file, id, strerror(errno));
return -1;
}
- p = ep->cache;
- n = ep->csize * ep->size;
+ p = buf;
+ n = count * ep->size;
while (n > 0) {
ret = read(ep->fd, p, n);
if (ret < 0) {
- if (errno != EAGAIN) {
- logerror("Error reading %s (%s)", ep->file, strerror(errno));
+ if (errno != EINTR) {
+ logerror("Error reading %s elt %d (%s)",
+ ep->file,
+ id + (int)((p - (char *)buf) / ep->size),
+ strerror(errno));
break;
}
} else if (ret == 0) {
+ logerror("Unexpected EOF reading %s elt %d",
+ ep->file, id + (int)((p - (char *)buf) / ep->size));
break;
} else {
p += ret;
}
}
- if (p == ep->cache)
- return -1; /* nothing read, old cache still ok */
-
- ep->baseid = start;
- ep->cids = (p - ep->cache) / ep->size;
- return ep->cids;
+ return (p - (char *)buf) / ep->size;
}
/*
- * Write COUNT elements from BUF to EP, starting at ID.
- * Return 0 on success, -1 on error.
+ * Write COUNT elements starting at ID from BUF to file-backed EP.
+ * Update the timestamp if the table is EFF_TYPED.
+ * Don't actually write if table is privately mapped.
+ * Return 0 on success, -1 on error (file may be corrupt then).
*/
static int
do_write(struct empfile *ep, void *buf, int id, int count)
{
- int n, ret;
+ int i, n, ret;
char *p;
+ struct emptypedstr *elt;
+ time_t now;
if (CANT_HAPPEN(ep->fd < 0 || id < 0 || count < 0))
return -1;
+ if (ep->flags & EFF_TYPED) {
+ now = ep->flags & EFF_NOTIME ? (time_t)-1 : time(NULL);
+ for (i = 0; i < count; i++) {
+ /*
+ * TODO Oopses here could be due to bad data corruption.
+ * Fail instead of attempting to recover?
+ */
+ elt = (struct emptypedstr *)((char *)buf + i * ep->size);
+ if (CANT_HAPPEN(elt->ef_type != ep->uid))
+ elt->ef_type = ep->uid;
+ if (CANT_HAPPEN(elt->uid != id + i))
+ elt->uid = id + i;
+ if (now != (time_t)-1)
+ elt->timestamp = now;
+ }
+ }
+
+ if (ep->flags & EFF_PRIVATE)
+ return 0;
+
if (lseek(ep->fd, id * ep->size, SEEK_SET) == (off_t)-1) {
- logerror("Error seeking %s (%s)", ep->file, strerror(errno));
+ logerror("Error seeking %s to elt %d (%s)",
+ ep->file, id, strerror(errno));
return -1;
}
while (n > 0) {
ret = write(ep->fd, p, n);
if (ret < 0) {
- if (errno != EAGAIN) {
- logerror("Error writing %s (%s)", ep->file, strerror(errno));
- /* FIXME if this extended file, truncate back to old size */
+ if (errno != EINTR) {
+ logerror("Error writing %s elt %d (%s)",
+ ep->file,
+ id + (int)((p - (char *)buf) / ep->size),
+ strerror(errno));
return -1;
}
} else {
}
/*
- * Write element ID into file-backed table TYPE from buffer FROM.
+ * Write element ID into table TYPE from buffer FROM.
* FIXME pass buffer size!
- * Write through cache straight to disk.
+ * Update timestamp in FROM if table is EFF_TYPED.
+ * If table is file-backed and not privately mapped, write through
+ * cache straight to disk.
* Cannot write beyond the end of fully cached table (flags & EFF_MEM).
* Can write at the end of partially cached table.
+ * FROM must be fresh; see ef_make_stale().
* Return non-zero on success, zero on failure.
*/
int
ef_write(int type, int id, void *from)
{
struct empfile *ep;
- char *to;
+ char *cachep;
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
- if (ep->prewrite)
- ep->prewrite(id, from);
- if (CANT_HAPPEN((ep->flags & EFF_MEM) ? id >= ep->fids : id > ep->fids))
- return 0; /* not implemented */
- if (do_write(ep, from, id, 1) < 0)
+ if (CANT_HAPPEN((ep->flags & (EFF_MEM | EFF_PRIVATE)) == EFF_PRIVATE))
return 0;
- if (id >= ep->baseid && id < ep->baseid + ep->cids) {
- /* update the cache if necessary */
- to = ep->cache + (id - ep->baseid) * ep->size;
- if (to != from)
- memcpy(to, from, ep->size);
- }
+ new_seqno(ep, from);
if (id >= ep->fids) {
- /* write beyond end of file extends it, take note */
+ /* beyond end of file */
+ if (CANT_HAPPEN((ep->flags & EFF_MEM) || id > ep->fids))
+ return 0; /* not implemented */
+ /* write at end of file extends it */
ep->fids = id + 1;
+ if (ep->onresize)
+ ep->onresize(type);
}
+ if (id >= ep->baseid && id < ep->baseid + ep->cids) {
+ cachep = ep->cache + (id - ep->baseid) * ep->size;
+ if (cachep != from)
+ must_be_fresh(ep, from);
+ } else
+ cachep = NULL;
+ if (ep->prewrite)
+ ep->prewrite(id, cachep, from);
+ if (ep->fd >= 0) {
+ if (do_write(ep, from, id, 1) < 0)
+ return 0;
+ }
+ if (cachep && cachep != from) /* update the cache if necessary */
+ memcpy(cachep, from, ep->size);
return 1;
}
/*
- * Extend the file-backed table TYPE by COUNT elements.
+ * Change element id.
+ * BUF is an element of table TYPE.
+ * ID is its new element ID.
+ * If table is EFF_TYPED, change id and sequence number stored in BUF.
+ * Else do nothing.
+ */
+void
+ef_set_uid(int type, void *buf, int uid)
+{
+ struct emptypedstr *elt;
+ struct empfile *ep;
+
+ if (ef_check(type) < 0)
+ return;
+ ep = &empfile[type];
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ elt = buf;
+ if (elt->uid == uid)
+ return;
+ elt->uid = uid;
+ elt->seqno = get_seqno(ep, uid);
+}
+
+/*
+ * Return sequence number of element ID in table EP.
+ * Return zero if table is not EFF_TYPED (it has no sequence number
+ * then).
+ */
+static unsigned
+get_seqno(struct empfile *ep, int id)
+{
+ struct emptypedstr *elt;
+
+ if (!(ep->flags & EFF_TYPED))
+ return 0;
+ if (id < 0 || id >= ep->fids)
+ return 0;
+ if (id >= ep->baseid && id < ep->baseid + ep->cids)
+ elt = (void *)(ep->cache + (id - ep->baseid) * ep->size);
+ else {
+ /* need a buffer, steal last cache slot */
+ if (ep->cids == ep->csize)
+ ep->cids--;
+ elt = (void *)(ep->cache + ep->cids * ep->size);
+ if (do_read(ep, elt, id, 1) < 0)
+ return 0; /* deep trouble */
+ }
+ return elt->seqno;
+}
+
+/*
+ * Increment sequence number in BUF, which is about to be written to EP.
+ * Do nothing if table is not EFF_TYPED (it has no sequence number
+ * then).
+ * Else, BUF's sequence number must match the one in EP's cache. If
+ * it doesn't, we're about to clobber a previous write.
+ */
+static void
+new_seqno(struct empfile *ep, void *buf)
+{
+ struct emptypedstr *elt = buf;
+ unsigned old_seqno;
+
+ if (!(ep->flags & EFF_TYPED))
+ return;
+ old_seqno = get_seqno(ep, elt->uid);
+ CANT_HAPPEN(old_seqno != elt->seqno);
+ elt->seqno = old_seqno + 1;
+}
+
+/*
+ * Make all copies stale.
+ * Only fresh copies may be written back to the cache.
+ * To be called by functions that may yield the processor.
+ * Writing an copy when there has been a yield since it was read is
+ * unsafe, because we could clobber another thread's write then.
+ * Robust code must assume the that any function that may yield does
+ * yield. Marking copies stale there lets us catch unsafe writes.
+ */
+void
+ef_make_stale(void)
+{
+ ef_generation++;
+}
+
+/* Mark copy of an element of table TYPE in BUF fresh. */
+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.
* Return non-zero on success, zero on failure.
*/
int
ef_extend(int type, int count)
{
struct empfile *ep;
- void *tmpobj;
- int id, i, how;
+ char *p;
+ int need_sentinel, i, id;
- if (ef_check(type) < 0)
+ if (ef_check(type) < 0 || CANT_HAPPEN(EF_IS_VIEW(type)))
return 0;
ep = &empfile[type];
- if (CANT_HAPPEN(ep->fd < 0 || count < 0))
+ if (CANT_HAPPEN(count < 0))
return 0;
- tmpobj = calloc(1, ep->size);
id = ep->fids;
+ if (ep->flags & EFF_MEM) {
+ need_sentinel = (ep->flags & EFF_SENTINEL) != 0;
+ if (id + count + need_sentinel > ep->csize) {
+ if (ep->flags & EFF_STATIC) {
+ logerror("Can't extend %s beyond %d elements",
+ ep->name, ep->csize - need_sentinel);
+ return 0;
+ }
+ if (!ef_realloc_cache(ep, id + count + need_sentinel)) {
+ logerror("Can't extend %s to %d elements (%s)",
+ ep->name, id + count, strerror(errno));
+ return 0;
+ }
+ }
+ p = ep->cache + id * ep->size;
+ do_blank(ep, p, id, count);
+ if (ep->fd >= 0) {
+ if (do_write(ep, p, id, count) < 0)
+ return 0;
+ }
+ if (need_sentinel)
+ memset(ep->cache + (id + count) * ep->size, 0, ep->size);
+ ep->cids = id + count;
+ } else {
+ /* need a buffer, steal last cache slot */
+ if (ep->cids == ep->csize)
+ ep->cids--;
+ p = ep->cache + ep->cids * ep->size;
+ for (i = 0; i < count; i++) {
+ do_blank(ep, p, id + i, 1);
+ if (do_write(ep, p, id + i, 1) < 0)
+ return 0;
+ }
+ }
+ ep->fids = id + count;
+ if (ep->onresize)
+ ep->onresize(type);
+ return 1;
+}
+
+/*
+ * Initialize element ID for table TYPE in BUF.
+ * FIXME pass buffer size!
+ * BUF is marked fresh with ef_mark_fresh().
+ */
+void
+ef_blank(int type, int id, void *buf)
+{
+ struct empfile *ep;
+ struct emptypedstr *elt;
+
+ if (ef_check(type) < 0)
+ return;
+ ep = &empfile[type];
+ do_blank(ep, buf, id, 1);
+ if (ep->flags & EFF_TYPED) {
+ elt = buf;
+ elt->seqno = get_seqno(ep, elt->uid);
+ }
+ ef_mark_fresh(type, buf);
+}
+
+/*
+ * Initialize COUNT elements of EP in BUF, starting with element ID.
+ */
+static void
+do_blank(struct empfile *ep, void *buf, int id, int count)
+{
+ int i;
+ struct emptypedstr *elt;
+
+ memset(buf, 0, count * ep->size);
for (i = 0; i < count; i++) {
- if (ep->init)
- ep->init(id + i, tmpobj);
- if (do_write(ep, tmpobj, id + i, 1) < 0)
- break;
+ elt = (struct emptypedstr *)((char *)buf + i * ep->size);
+ if (ep->flags & EFF_TYPED) {
+ elt->ef_type = ep->uid;
+ elt->uid = id + i;
+ }
+ if (ep->oninit)
+ ep->oninit(elt);
+ }
+}
+
+/*
+ * Truncate table TYPE to COUNT elements.
+ * Any pointers obtained from ef_ptr() become invalid.
+ * Return non-zero on success, zero on failure.
+ */
+int
+ef_truncate(int type, int count)
+{
+ struct empfile *ep;
+ int need_sentinel;
+
+ if (ef_check(type) < 0 || CANT_HAPPEN(EF_IS_VIEW(type)))
+ return 0;
+ ep = &empfile[type];
+ if (CANT_HAPPEN(count < 0 || count > ep->fids))
+ return 0;
+
+ if (ep->fd >= 0 && !(ep->flags & EFF_PRIVATE)) {
+ if (ftruncate(ep->fd, count * ep->size) < 0) {
+ logerror("Can't truncate %s to %d elements (%s)",
+ ep->file, count, strerror(errno));
+ return 0;
+ }
}
- free(tmpobj);
+ ep->fids = count;
if (ep->flags & EFF_MEM) {
- /* FIXME lazy bastards... do this right */
- /* XXX this will cause problems if there are ef_ptrs (to the
- * old allocated structure) active when we do the re-open */
- how = ep->flags & ~EFF_IMMUTABLE;
- ef_close(type);
- ef_open(type, how);
+ need_sentinel = (ep->flags & EFF_SENTINEL) != 0;
+ if (!(ep->flags & EFF_STATIC)) {
+ if (!ef_realloc_cache(ep, count + need_sentinel)) {
+ logerror("Can't shrink %s cache after truncate (%s)",
+ ep->name, strerror(errno));
+ /* continue with unshrunk cache */
+ }
+ }
+ if (need_sentinel)
+ memset(ep->cache + count * ep->size, 0, ep->size);
+ ep->cids = count;
} else {
- ep->fids += i;
+ if (ep->baseid >= count)
+ ep->cids = 0;
+ else if (ep->cids > count - ep->baseid)
+ ep->cids = count - ep->baseid;
}
- return i == count;
+ if (ep->onresize)
+ ep->onresize(type);
+ return 1;
}
struct castr *
ef_cadef(int type)
{
+ if (ef_check(type) < 0)
+ return NULL;
return empfile[type].cadef;
}
int
ef_nelem(int type)
{
+ if (ef_check(type) < 0)
+ return 0;
return empfile[type].fids;
}
int
ef_flags(int type)
{
+ if (ef_check(type) < 0)
+ return 0;
return empfile[type].flags;
}
time_t
ef_mtime(int type)
{
+ if (ef_check(type) < 0)
+ return 0;
if (empfile[type].fd <= 0)
return 0;
return fdate(empfile[type].fd);
return empfile[type].name;
}
-int
+static int
ef_check(int type)
{
if (CANT_HAPPEN((unsigned)type >= EF_MAX))
}
/*
- * Ensure file-backed table contains ID.
+ * Ensure table contains element ID.
* If necessary, extend it in steps of COUNT elements.
* Return non-zero on success, zero on failure.
*/
}
return 1;
}
-
-static void
-ef_fix_size(struct empfile *ep, int n)
-{
- ep->cids = ep->fids = n;
- ep->csize = n + 1;
-}
-
-/*
- * Initialize Empire tables.
- * Must be called once, before using anything else from this module.
- */
-void
-ef_init(void)
-{
- struct castr *ca;
- struct empfile *ep;
- struct symbol *lup;
- int i;
-
- empfile[EF_MAP].size = empfile[EF_BMAP].size = (WORLD_X * WORLD_Y) / 2;
-
- ca = (struct castr *)empfile[EF_META].cache;
- for (i = 0; ca[i].ca_name; i++) ;
- ef_fix_size(&empfile[EF_META], i);
-
- for (ep = empfile; ep->uid >= 0; ep++) {
- if (ep->cadef == symbol_ca) {
- lup = (struct symbol *)ep->cache;
- for (i = 0; lup[i].name; i++) ;
- ef_fix_size(ep, i);
- }
- }
-}
projects / empserver / blobdiff