/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2008, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1986-2016, 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, 2005-2008
+ * Markus Armbruster, 2005-2014
*/
#include <config.h>
#include <errno.h>
#include <fcntl.h>
+#include <limits.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 int do_extend(struct empfile *, int);
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
+ * 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.
+ * The table must not be already open.
* 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, int nelt)
+ef_open(int type, int how)
{
struct empfile *ep;
- struct flock lock;
- int oflags, fd, fsiz, nslots;
+ int oflags, fd, fsiz, fids, nslots, fail;
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;
+ if (CANT_HAPPEN(ep->prewrite && !(how & EFF_MEM)))
+ return 0; /* not implemented */
oflags = O_RDWR;
if (how & EFF_PRIVATE)
oflags = O_RDONLY;
if (how & EFF_CREATE)
oflags |= O_CREAT | O_TRUNC;
-#if defined(_WIN32)
- oflags |= O_BINARY;
-#endif
- 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_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) {
- logerror("Can't open %s (file size not a multiple of record size %d)",
- ep->file, ep->size);
- close(fd);
- return 0;
- }
- ep->fids = fsiz / ep->size;
- if (nelt >= 0 && nelt != ep->fids) {
- logerror("Can't open %s (got %d records instead of %d)",
- ep->file, ep->fids, nelt);
- close(fd);
- return 0;
+ if (how & EFF_CREATE) {
+ fids = ep->nent >= 0 ? ep->nent : 0;
+ } else {
+ fsiz = fsize(fd);
+ if (fsiz % ep->size) {
+ logerror("Can't open %s (file size not a multiple of record size %d)",
+ ep->file, ep->size);
+ close(fd);
+ return 0;
+ }
+ fids = fsiz / ep->size;
+ if (ep->nent >= 0 && ep->nent != fids) {
+ logerror("Can't open %s (got %d records instead of %d)",
+ ep->file, fids, ep->nent);
+ 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) {
+ CANT_HAPPEN(ep->nent >= 0); /* insufficient static cache */
+ logerror("Can't open %s (file larger than %d records)",
+ ep->file, ep->csize);
close(fd);
return 0;
}
if (CANT_HAPPEN(ep->cache))
free(ep->cache);
if (how & EFF_MEM)
- nslots = ep->fids;
+ nslots = fids;
else
nslots = blksize(fd) / ep->size;
if (!ef_realloc_cache(ep, nslots)) {
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) {
- ep->cids = 0; /* prevent cache flush */
- ep->flags &= EFF_IMMUTABLE; /* maintain invariant */
- ef_close(type);
- return 0;
- }
+ if (how & EFF_CREATE) {
+ /* populate new file */
+ ep->fids = 0;
+ fail = !do_extend(ep, fids);
+ } else {
+ ep->fids = fids;
+ if ((how & EFF_MEM) && fids)
+ fail = fillcache(ep, 0) != fids;
+ else
+ fail = 0;
+ }
+ if (fail) {
+ ep->cids = 0; /* prevent cache flush */
+ 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.
+ * 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()
}
/*
- * 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->nent != empfile[base].nent
+ || 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 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.
}
/*
- * Return pointer to element ID in table TYPE if it exists, else NULL.
+ * Return pointer to element @id in table @type if it exists, else NULL.
* The table must be fully cached, i.e. flags & EFF_MEM.
* The caller is responsible for flushing changes he makes.
*/
}
/*
- * Read element ID from table TYPE into buffer INTO.
+ * 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 file-backed 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 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, id * ep->size, SEEK_SET) == (off_t)-1) {
return -1;
}
- p = ep->cache;
- n = MIN(ep->csize, ep->fids - id) * ep->size;
+ p = buf;
+ n = count * ep->size;
while (n > 0) {
ret = read(ep->fd, p, n);
if (ret < 0) {
if (errno != EINTR) {
logerror("Error reading %s elt %d (%s)",
ep->file,
- id + (int)((p - ep->cache) / ep->size),
+ 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 - ep->cache) / ep->size));
+ 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 = id;
- ep->cids = (p - ep->cache) / ep->size;
- return ep->cids;
+ return (p - (char *)buf) / ep->size;
}
/*
- * Write COUNT elements starting at ID from BUF to file-backed EP.
+ * 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).
{
int i, n, ret;
char *p;
- struct emptypedstr *elt;
+ struct ef_typedstr *elt;
time_t now;
if (CANT_HAPPEN(ep->fd < 0 || id < 0 || count < 0))
return -1;
if (ep->flags & EFF_TYPED) {
- now = time(NULL);
+ 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);
+ elt = (struct ef_typedstr *)((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;
- elt->timestamp = now;
+ if (now != (time_t)-1)
+ elt->timestamp = now;
}
}
}
/*
- * Write element ID into table TYPE from buffer FROM.
+ * Write element @id into table @type from buffer @from.
* FIXME pass buffer size!
- * Update timestamp in FROM if table is EFF_TYPED.
+ * 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 (CANT_HAPPEN((ep->flags & (EFF_MEM | EFF_PRIVATE)) == EFF_PRIVATE))
return 0;
+ if (CANT_HAPPEN(id < 0))
+ return 0;
+ if (CANT_HAPPEN(ep->nent >= 0 && id >= ep->nent))
+ return 0; /* beyond fixed size */
+ new_seqno(ep, from);
+ if (id >= ep->fids) {
+ /* 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, from);
- if (CANT_HAPPEN((ep->flags & EFF_MEM) ? id >= ep->fids : id > ep->fids))
- return 0; /* not implemented */
+ ep->prewrite(id, cachep, from);
if (ep->fd >= 0) {
if (do_write(ep, from, id, 1) < 0)
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);
- }
- if (id >= ep->fids) {
- /* write beyond end of file extends it, take note */
- ep->fids = id + 1;
- }
+ if (cachep && cachep != from) /* update the cache if necessary */
+ memcpy(cachep, from, ep->size);
return 1;
}
/*
- * Extend 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 ef_typedstr *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);
+}
+
+/*
+ * Are *A and *B equal, except for timestamps and such?
+ */
+int
+ef_typedstr_eq(struct ef_typedstr *a, struct ef_typedstr *b)
+{
+ return a->ef_type == b->ef_type
+ && a->seqno == b->seqno
+ && a->uid == b->uid
+ && !memcmp((char *)a + sizeof(*a), (char *)b + sizeof(*a),
+ empfile[a->ef_type].size - sizeof(*a));
+}
+
+/*
+ * 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 ef_typedstr *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 ef_typedstr *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 ef_typedstr *)buf)->generation = ef_generation;
+}
+
+static void
+must_be_fresh(struct empfile *ep, void *buf)
+{
+ struct ef_typedstr *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.
*/
ef_extend(int type, int count)
{
struct empfile *ep;
- char *p;
- int i, id;
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
- if (CANT_HAPPEN(count < 0))
+ if (ep->nent >= 0) {
+ logerror("Can't extend %s, its size is fixed", ep->name);
+ return 0;
+ }
+ if (!do_extend(ep, count))
+ return 0;
+ if (ep->onresize)
+ ep->onresize(type);
+ return 1;
+}
+
+static int
+do_extend(struct empfile *ep, int count)
+{
+ char *p;
+ int need_sentinel, i, id;
+
+ if (CANT_HAPPEN(EF_IS_VIEW(ep->uid)) || count < 0)
return 0;
id = ep->fids;
if (ep->flags & EFF_MEM) {
- if (id + count > ep->csize) {
+ 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->file, ep->csize);
+ ep->name, ep->csize - need_sentinel);
return 0;
}
- if (!ef_realloc_cache(ep, id + count)) {
+ if (!ef_realloc_cache(ep, id + count + need_sentinel)) {
logerror("Can't extend %s to %d elements (%s)",
- ep->file, id + count, strerror(errno));
+ ep->name, id + count, strerror(errno));
return 0;
}
}
if (do_write(ep, p, id, count) < 0)
return 0;
}
- ep->cids += count;
+ 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)
return 0;
}
}
- ep->fids += count;
+ ep->fids = id + count;
return 1;
}
/*
- * Initialize element ID for EP in BUF.
+ * 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 ef_typedstr *elt;
+
if (ef_check(type) < 0)
return;
- do_blank(&empfile[type], buf, id, 1);
+ 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.
+ * 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;
+ struct ef_typedstr *elt;
memset(buf, 0, count * ep->size);
- if (ep->flags & EFF_TYPED) {
- for (i = 0; i < count; i++) {
- elt = (struct emptypedstr *)((char *)buf + i * ep->size);
+ for (i = 0; i < count; i++) {
+ elt = (struct ef_typedstr *)((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.
+ * Truncate table @type to @count elements.
* Any pointers obtained from ef_ptr() become invalid.
* Return non-zero on success, zero on failure.
*/
ef_truncate(int type, int count)
{
struct empfile *ep;
+ int need_sentinel;
- if (ef_check(type) < 0)
+ if (ef_check(type) < 0 || CANT_HAPPEN(EF_IS_VIEW(type)))
return 0;
ep = &empfile[type];
+ if (ep->nent >= 0) {
+ logerror("Can't truncate %s, its size is fixed", ep->name);
+ return 0;
+ }
if (CANT_HAPPEN(count < 0 || count > ep->fids))
return 0;
ep->fids = count;
if (ep->flags & EFF_MEM) {
+ need_sentinel = (ep->flags & EFF_SENTINEL) != 0;
if (!(ep->flags & EFF_STATIC)) {
- if (!ef_realloc_cache(ep, count)) {
- logerror("Can't shrink cache after truncate");
+ 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 {
if (ep->baseid >= count)
ep->cids = count - ep->baseid;
}
+ 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);
}
/*
- * Search for a table matching NAME, return its table type.
+ * Search for a table matching @name, return its table type.
* Return M_NOTFOUND if there are no matches, M_NOTUNIQUE if there are
* several.
*/
}
/*
- * Search CHOICES[] for a table type matching NAME, return it.
+ * Search @choices[] for a table type matching @name, return it.
* Return M_NOTFOUND if there are no matches, M_NOTUNIQUE if there are
* several.
- * CHOICES[] must be terminated with a negative value.
+ * @choices[] must be terminated with a negative value.
*/
int
ef_byname_from(char *name, int choices[])
return res;
}
+/*
+ * Return name of table @type. Always a single, short word.
+ */
char *
ef_nameof(int type)
{
if (ef_check(type) < 0)
- return "bad ef_type";
+ return "bad";
return empfile[type].name;
}
-int
+/*
+ * Return "pretty" name of table @type.
+ */
+char *
+ef_nameof_pretty(int type)
+{
+ if (ef_check(type) < 0)
+ return "bad";
+ return empfile[type].pretty_name;
+}
+
+static int
ef_check(int type)
{
if (CANT_HAPPEN((unsigned)type >= EF_MAX))
}
/*
- * Ensure file-backed table contains ID.
- * If necessary, extend it in steps of COUNT elements.
+ * Ensure table @type contains element @id.
+ * If necessary, extend it in steps of @count elements.
* Return non-zero on success, zero on failure.
*/
int
ef_ensure_space(int type, int id, int count)
{
- if (ef_check(type) < 0)
+ if (ef_check(type) < 0 || CANT_HAPPEN(id < 0))
return 0;
- CANT_HAPPEN(id < 0);
while (id >= empfile[type].fids) {
if (!ef_extend(type, count))
}
return 1;
}
+
+/*
+ * Return maximum ID acceptable for table @type.
+ * Assuming infinite memory and disk space.
+ */
+int
+ef_id_limit(int type)
+{
+ struct empfile *ep;
+
+ if (ef_check(type) < 0)
+ return -1;
+ ep = &empfile[type];
+ if (ep->nent >= 0)
+ return ep->nent - 1;
+ if (ep->flags & EFF_MEM) {
+ if (ep->flags & EFF_STATIC)
+ return ep->csize - 1 - ((ep->flags & EFF_SENTINEL) != 0);
+ }
+ return INT_MAX;
+}
projects / empserver / blobdiff