/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2005, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Copyright (C) 1986-2008, Dave Pare, Jeff Bailey, Thomas Ruschak,
* Ken Stevens, Steve McClure
*
* This program is free software; you can redistribute it and/or modify
*
* ---
*
- * See the "LEGAL", "LICENSE", "CREDITS" and "README" files for all the
- * related information and legal notices. It is expected that any future
- * projects/authors will amend these files as needed.
+ * See files README, COPYING and CREDITS in the root of the source
+ * tree for related information and legal notices. It is expected
+ * that future projects/authors will amend these files as needed.
*
* ---
*
- * file.c: Misc. operations on files
+ * 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
*/
+#include <config.h>
+
#include <errno.h>
#include <fcntl.h>
-#include <signal.h>
-#include <stdlib.h>
-#include <string.h>
-#if !defined(_WIN32)
+#include <sys/stat.h>
+#include <sys/types.h>
#include <unistd.h>
-#endif
+#include "file.h"
+#include "match.h"
#include "misc.h"
#include "nsc.h"
-#include "file.h"
-#include "common.h"
-#include "gen.h"
-
+#include "prototypes.h"
+static int ef_remap_cache(struct empfile *, int);
static int fillcache(struct empfile *, int);
static int do_write(struct empfile *, void *, int, int);
-
+static void ef_blank(struct empfile *, void *, int, int);
/*
- * Open the binary file for table TYPE (EF_SECTOR, ...).
- * HOW are EFF_OPEN flags to control operation.
+ * Open the file-backed table TYPE (EF_SECTOR, ...).
+ * HOW are flags to control operation. Naturally, immutable flags are
+ * not permitted.
* Return non-zero on success, zero on failure.
* You must call ef_close() before the next ef_open().
*/
ef_open(int type, int how)
{
struct empfile *ep;
- int oflags, fd, fsiz, size;
+ struct flock lock;
+ int oflags, fd, fsiz, nslots;
if (ef_check(type) < 0)
return 0;
- if (CANT_HAPPEN(how & ~EFF_OPEN))
- how &= EFF_OPEN;
+ if (CANT_HAPPEN(how & EFF_IMMUTABLE))
+ how &= ~EFF_IMMUTABLE;
+
+ /* open file */
ep = &empfile[type];
if (CANT_HAPPEN(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;
#endif
- if ((fd = open(ep->file, oflags, 0660)) < 0) {
+ if ((fd = open(ep->file, oflags, S_IRWUG)) < 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)",
return 0;
}
ep->fids = fsiz / ep->size;
- if (how & EFF_MEM)
- ep->csize = ep->fids;
- else
- ep->csize = max(1, blksize(fd) / ep->size);
- size = ep->csize * ep->size;
- ep->cache = malloc(size);
- if (ep->cache == NULL) {
- logerror("Can't open %s: out of memory", ep->file);
- 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);
+ close(fd);
+ return 0;
+ }
+ }
+ } else {
+ if (CANT_HAPPEN(ep->cache))
+ free(ep->cache);
+ if (how & EFF_MEM)
+ nslots = ep->fids;
+ else
+ nslots = blksize(fd) / ep->size;
+ if (!ef_remap_cache(ep, nslots)) {
+ logerror("Can't open %s: out of memory", ep->file);
+ close(fd);
+ return 0;
+ }
}
ep->baseid = 0;
ep->cids = 0;
- ep->flags = (ep->flags & ~EFF_OPEN) | (how ^ ~EFF_CREATE);
+ ep->flags = (ep->flags & EFF_IMMUTABLE) | (how & ~EFF_CREATE);
ep->fd = fd;
- if (how & EFF_MEM) {
+
+ /* 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_OPEN; /* maintain invariant */
+ ep->flags &= EFF_IMMUTABLE; /* maintain invariant */
ef_close(type);
return 0;
}
}
+
+ return 1;
+}
+
+static int
+ef_remap_cache(struct empfile *ep, int nslots)
+{
+ void *cache;
+
+ if (CANT_HAPPEN(ep->flags & EFF_STATIC))
+ return 0;
+ if (CANT_HAPPEN(nslots < 0))
+ nslots = 0;
+
+ /*
+ * Avoid zero slots, because that can lead to null cache, which
+ * would be interpreted as unmapped cache.
+ */
+ if (nslots == 0)
+ nslots++;
+ cache = realloc(ep->cache, nslots * ep->size);
+ if (!cache)
+ return 0;
+
+ ep->cache = cache;
+ ep->csize = nslots;
return 1;
}
/*
- * Close the file containing objects of the type 'type', flushing the cache
- * if applicable.
+ * Close the file-backed table TYPE (EF_SECTOR, ...).
+ * Return non-zero on success, zero on failure.
*/
int
ef_close(int type)
retval = ef_flush(type);
ep = &empfile[type];
- ep->flags &= ~EFF_OPEN;
- free(ep->cache);
- ep->cache = NULL;
+ ep->flags &= EFF_IMMUTABLE;
+ if (!(ep->flags & EFF_STATIC)) {
+ free(ep->cache);
+ ep->cache = NULL;
+ }
if (close(ep->fd) < 0) {
logerror("Error closing %s (%s)", ep->name, strerror(errno));
retval = 0;
}
/*
- * Flush the cache of the file containing objects of type 'type' to disk.
+ * Flush table TYPE (EF_SECTOR, ...) to disk.
+ * Does nothing if the table is privately mapped.
+ * Return non-zero on success, zero on failure.
*/
int
ef_flush(int type)
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))
+ if (ep->flags & EFF_MEM)
return do_write(ep, ep->cache, ep->baseid, ep->cids) >= 0;
return 1;
}
/*
- * Return a pointer the id 'id' of object of type 'type' in the cache.
+ * 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.
*/
-char *
+void *
ef_ptr(int type, int id)
{
struct empfile *ep;
if (ef_check(type) < 0)
return NULL;
ep = &empfile[type];
- if (id < 0 || id >= ep->fids)
+ if (CANT_HAPPEN(!(ep->flags & EFF_MEM) || !ep->cache))
return NULL;
- if ((ep->flags & EFF_MEM) == 0) {
- logerror("ef_ptr: (%s) only valid for EFF_MEM entries", ep->file);
+ if (id < 0 || id >= ep->fids)
return NULL;
- }
return ep->cache + ep->size * id;
}
/*
- * buffered read. Tries to read a large number of items.
- * This system won't work if item size is > sizeof buffer area.
+ * Read element ID from table TYPE into buffer INTO.
+ * FIXME pass buffer size!
+ * Return non-zero on success, zero on failure.
*/
int
ef_read(int type, int id, void *into)
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
- if (id < 0)
+ if (CANT_HAPPEN(!ep->cache))
+ return 0;
+ if (id < 0 || id >= ep->fids)
return 0;
+
if (ep->flags & EFF_MEM) {
- if (id >= ep->fids)
- return 0;
- from = ep->cache + (id * ep->size);
+ from = ep->cache + id * ep->size;
} else {
- if (id >= ep->fids) {
- ep->fids = fsize(ep->fd) / ep->size;
- if (id >= ep->fids)
- return 0;
- }
- if (ep->baseid + ep->cids <= id || ep->baseid > id)
+ if (ep->baseid + ep->cids <= id || ep->baseid > id) {
if (fillcache(ep, id) < 1)
return 0;
+ }
from = ep->cache + (id - ep->baseid) * ep->size;
}
memcpy(into, from, ep->size);
int n, ret;
char *p;
- if (CANT_HAPPEN(ep->fd < 0 || id < 0 || count < 0))
+ if (CANT_HAPPEN(ep->fd < 0 || (ep->flags & EFF_PRIVATE)
+ || id < 0 || count < 0))
return -1;
if (lseek(ep->fd, id * ep->size, SEEK_SET) == (off_t)-1) {
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 */
return -1;
}
} else {
}
/*
- * buffered write. Modifies read cache (if applicable)
- * and writes through to disk.
+ * Write element ID into table TYPE from buffer FROM.
+ * FIXME pass buffer size!
+ * 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.
+ * Return non-zero on success, zero on failure.
*/
int
ef_write(int type, int id, void *from)
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
- if (id > 65536) {
- /* largest unit id; this may bite us in large games */
- logerror("ef_write: type %d id %d is too large!\n", type, id);
+ if (CANT_HAPPEN((ep->flags & (EFF_MEM | EFF_PRIVATE)) == EFF_PRIVATE))
return 0;
- }
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)
- return 0;
+ if (!(ep->flags & EFF_PRIVATE)) {
+ 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;
- memcpy(to, from, ep->size);
+ if (to != from)
+ memcpy(to, from, ep->size);
}
- CANT_HAPPEN(id > ep->fids);
if (id >= ep->fids) {
/* write beyond end of file extends it, take note */
ep->fids = id + 1;
}
/*
- * Grow the file containing objects of the type 'type' by 'count' objects.
+ * 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;
- char *tmpobj;
- int cur, max;
- int how;
- int r;
+ char *p;
+ int i, id;
if (ef_check(type) < 0)
return 0;
ep = &empfile[type];
- max = ep->fids + count;
- cur = ep->fids;
- tmpobj = calloc(1, ep->size);
- if ((r = lseek(ep->fd, ep->fids * ep->size, SEEK_SET)) < 0) {
- logerror("ef_extend: %s +#%d lseek(%d, %d, SEEK_SET) -> %d",
- ep->name, count, ep->fd, ep->fids * ep->size, r);
- free(tmpobj);
+ if (CANT_HAPPEN(count < 0))
return 0;
- }
- for (cur = ep->fids; cur < max; cur++) {
- if (ep->init)
- ep->init(cur, tmpobj);
- if ((r = write(ep->fd, tmpobj, ep->size)) != ep->size) {
- logerror("ef_extend: %s +#%d write(%d, %p, %d) -> %d",
- ep->name, count, ep->fd, tmpobj, ep->size, r);
- free(tmpobj);
- return 0;
- }
- }
- free(tmpobj);
+
+ id = ep->fids;
if (ep->flags & EFF_MEM) {
- /* 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;
- ef_close(type);
- ef_open(type, how);
+ if (id + count > ep->csize) {
+ if (ep->flags & EFF_STATIC)
+ return 0;
+ if (!ef_remap_cache(ep, id + count))
+ return 0;
+ }
+ p = ep->cache + id * ep->size;
+ ef_blank(ep, p, id, count);
+ if (!(ep->flags & EFF_PRIVATE)) {
+ if (do_write(ep, p, id, count) < 0)
+ return 0;
+ }
+ ep->cids += count;
} else {
- ep->fids += count;
+ /* 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++) {
+ ef_blank(ep, p, id + i, 1);
+ if (do_write(ep, p, id + i, 1) < 0)
+ return 0;
+ }
}
+ ep->fids += count;
return 1;
}
/*
- * Mark the cache for the file containing objects of type 'type' as unused.
+ * Initialize COUNT elements of EP in BUF, starting with element ID.
*/
-void
-ef_zapcache(int type)
+static void
+ef_blank(struct empfile *ep, void *buf, int id, int count)
{
- struct empfile *ep = &empfile[type];
- if ((ep->flags & EFF_MEM) == 0) {
- ep->cids = 0;
- ep->baseid = -1;
+ int i;
+
+ memset(buf, 0, count * ep->size);
+ if (ep->init) {
+ for (i = 0; i < count; i++)
+ ep->init(id + i, (char *)buf + i * ep->size);
}
}
}
/*
- * Search empfile[0..EF_MAX-1] for element named NAME.
- * Return its index in empfile[] if found, else -1.
+ * Search for a table matching NAME, return its table type.
+ * Return M_NOTFOUND if there are no matches, M_NOTUNIQUE if there are
+ * several.
*/
int
ef_byname(char *name)
{
- struct empfile *ef;
- int i;
- int len;
+ return stmtch(name, empfile, offsetof(struct empfile, name),
+ sizeof(empfile[0]));
+}
- len = strlen(name);
- for (i = 0; i < EF_MAX; i++) {
- ef = &empfile[i];
- if (strncmp(ef->name, name, min(len, strlen(ef->name))) == 0)
- return i;
+/*
+ * 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.
+ */
+int
+ef_byname_from(char *name, int choices[])
+{
+ int res;
+ int *p;
+
+ res = M_NOTFOUND;
+ for (p = choices; *p >= 0; p++) {
+ if (ef_check(*p) < 0)
+ continue;
+ switch (mineq(name, empfile[*p].name)) {
+ case ME_MISMATCH:
+ break;
+ case ME_PARTIAL:
+ if (res >= 0)
+ return M_NOTUNIQUE;
+ res = *p;
+ break;
+ case ME_EXACT:
+ return *p;
+ }
}
- return -1;
+ return res;
}
char *
ef_nameof(int type)
{
- if (type < 0 || type >= EF_MAX)
- return "bad item type";
+ if (ef_check(type) < 0)
+ return "bad ef_type";
return empfile[type].name;
}
int
ef_check(int type)
{
- if (type < 0 || type >= EF_MAX) {
- logerror("ef_ptr: bad EF_type %d\n", type);
+ if (CANT_HAPPEN((unsigned)type >= EF_MAX))
return -1;
- }
return 0;
}
+/*
+ * Ensure file-backed table contains 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)
+ return 0;
+ CANT_HAPPEN(id < 0);
+
while (id >= empfile[type].fids) {
if (!ef_extend(type, count))
return 0;