/*
* This file contains a set of abstractions that allow Citadel to plug into any
* record manager or database system for its data store.
+ *
+ * $Id$
*/
+/*
+ * Note that each call to a GDBM function is wrapped in an S_DATABASE critical
+ * section. This is done because GDBM is not threadsafe. This is the ONLY
+ * place in the entire Citadel server where any code enters two different
+ * classes of critical sections at the same time; this is why the GDBM calls
+ * are *tightly* wrapped in S_DATABASE. Opening multiple concurrent critical
+ * sections elsewhere in the code can, and probably will, cause deadlock
+ * conditions to occur. (Deadlock is bad. Eliminate.)
+ */
+#include "sysdep.h"
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
-#include <pthread.h>
+#ifdef HAVE_GDBM_H
#include <gdbm.h>
+#endif
#include "citadel.h"
#include "server.h"
#include "database.h"
/*
* We also keep these around, for sequential searches... (one per
- * session. Maybe there's a better way?)
+ * session. Maybe there's a better way?) FIX ... there _is_ a better
+ * way. We have TSD functions now; use them.
*/
#define MAXKEYS 256
datum dtkey[MAXKEYS];
void defrag_databases(void) {
/* defrag the message base */
+ lprintf(7, "Defragmenting message base\n");
begin_critical_section(S_MSGMAIN);
+ begin_critical_section(S_DATABASE);
gdbm_reorganize(gdbms[CDB_MSGMAIN]);
+ end_critical_section(S_DATABASE);
end_critical_section(S_MSGMAIN);
/* defrag the user file, mailboxes, and user/room relationships */
+ lprintf(7, "Defragmenting user file\n");
begin_critical_section(S_USERSUPP);
+ begin_critical_section(S_DATABASE);
gdbm_reorganize(gdbms[CDB_USERSUPP]);
gdbm_reorganize(gdbms[CDB_VISIT]);
+ end_critical_section(S_DATABASE);
end_critical_section(S_USERSUPP);
/* defrag the room files and message lists */
+ lprintf(7, "Defragmenting room files and message lists\n");
begin_critical_section(S_QUICKROOM);
+ begin_critical_section(S_DATABASE);
gdbm_reorganize(gdbms[CDB_QUICKROOM]);
gdbm_reorganize(gdbms[CDB_MSGLISTS]);
+ end_critical_section(S_DATABASE);
end_critical_section(S_QUICKROOM);
/* defrag the floor table */
+ lprintf(7, "Defragmenting floor table\n");
begin_critical_section(S_FLOORTAB);
+ begin_critical_section(S_DATABASE);
gdbm_reorganize(gdbms[CDB_FLOORTAB]);
+ end_critical_section(S_DATABASE);
end_critical_section(S_FLOORTAB);
}
void open_databases(void) {
int a;
+ lprintf(7, "%s\n", gdbm_version);
+
/*
* Silently try to create the database subdirectory. If it's
* already there, no problem.
*/
system("exec mkdir data 2>/dev/null");
+ /* a critical section is unnecessary, as this function is called before
+ any other threads are created. and it causes problems on BSDI.
+
+ begin_critical_section(S_DATABASE);
+
+ */
+
gdbms[CDB_MSGMAIN] = gdbm_open("data/msgmain.gdbm", 8192,
GDBM_WRCREAT, 0600, NULL);
if (gdbms[CDB_MSGMAIN] == NULL) {
lprintf(2, "Cannot open msgmain: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
gdbms[CDB_USERSUPP] = gdbm_open("data/usersupp.gdbm", 0,
if (gdbms[CDB_USERSUPP] == NULL) {
lprintf(2, "Cannot open usersupp: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
gdbms[CDB_VISIT] = gdbm_open("data/visit.gdbm", 0,
if (gdbms[CDB_VISIT] == NULL) {
lprintf(2, "Cannot open visit file: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
gdbms[CDB_QUICKROOM] = gdbm_open("data/quickroom.gdbm", 0,
if (gdbms[CDB_QUICKROOM] == NULL) {
lprintf(2, "Cannot open quickroom: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
gdbms[CDB_FLOORTAB] = gdbm_open("data/floortab.gdbm", 0,
if (gdbms[CDB_FLOORTAB] == NULL) {
lprintf(2, "Cannot open floortab: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
gdbms[CDB_MSGLISTS] = gdbm_open("data/msglists.gdbm", 0,
if (gdbms[CDB_MSGLISTS] == NULL) {
lprintf(2, "Cannot open msglists: %s\n",
gdbm_strerror(gdbm_errno));
+ exit(1);
}
for (a=0; a<MAXKEYS; ++a) {
dtkey[a].dptr = NULL;
}
+ /*
+ end_critical_section(S_DATABASE);
+ */
+
}
void close_databases(void) {
int a;
- /* Hmm... we should decide when would be a good time to defrag.
- * Server shutdowns might be an opportune time.
- defrag_databases(); */
-
+ begin_critical_section(S_DATABASE);
for (a=0; a<MAXCDB; ++a) {
lprintf(7, "Closing database %d\n", a);
gdbm_close(gdbms[a]);
}
+ end_critical_section(S_DATABASE);
for (a=0; a<MAXKEYS; ++a) {
if (dtkey[a].dptr != NULL) {
- free(dtkey[a].dptr);
+ phree(dtkey[a].dptr);
}
}
void *data, int datalen) {
datum dkey, ddata;
+ int retval;
dkey.dsize = keylen;
dkey.dptr = key;
ddata.dsize = datalen;
ddata.dptr = data;
- if ( gdbm_store(gdbms[cdb], dkey, ddata, GDBM_REPLACE) < 0 ) {
+ begin_critical_section(S_DATABASE);
+ retval = gdbm_store(gdbms[cdb], dkey, ddata, GDBM_REPLACE);
+ end_critical_section(S_DATABASE);
+ if ( retval < 0 ) {
lprintf(2, "gdbm error: %s\n", gdbm_strerror(gdbm_errno));
return(-1);
}
int cdb_delete(int cdb, void *key, int keylen) {
datum dkey;
+ int retval;
dkey.dsize = keylen;
dkey.dptr = key;
- return(gdbm_delete(gdbms[cdb], dkey));
+ begin_critical_section(S_DATABASE);
+ retval = gdbm_delete(gdbms[cdb], dkey);
+ end_critical_section(S_DATABASE);
+ return(retval);
}
dkey.dsize = keylen;
dkey.dptr = key;
+ begin_critical_section(S_DATABASE);
dret = gdbm_fetch(gdbms[cdb], dkey);
+ end_critical_section(S_DATABASE);
if (dret.dptr == NULL) {
return NULL;
}
- tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
+ tempcdb = (struct cdbdata *) mallok(sizeof(struct cdbdata));
if (tempcdb == NULL) {
lprintf(2, "Cannot allocate memory!\n");
}
* more complex stuff with other database managers in the future).
*/
void cdb_free(struct cdbdata *cdb) {
- free(cdb->ptr);
- free(cdb);
+ phree(cdb->ptr);
+ phree(cdb);
}
void cdb_rewind(int cdb) {
if (dtkey[CC->cs_pid].dptr != NULL) {
- free(dtkey[CC->cs_pid].dptr);
+ phree(dtkey[CC->cs_pid].dptr);
}
+ begin_critical_section(S_DATABASE);
dtkey[CC->cs_pid] = gdbm_firstkey(gdbms[cdb]);
+ end_critical_section(S_DATABASE);
}
return NULL;
}
+ begin_critical_section(S_DATABASE);
dret = gdbm_fetch(gdbms[cdb], dtkey[CC->cs_pid]);
+ end_critical_section(S_DATABASE);
if (dret.dptr == NULL) { /* bad read */
- free(dtkey[CC->cs_pid].dptr);
+ phree(dtkey[CC->cs_pid].dptr);
return NULL;
}
- cdbret = (struct cdbdata *) malloc(sizeof(struct cdbdata));
+ cdbret = (struct cdbdata *) mallok(sizeof(struct cdbdata));
cdbret->len = dret.dsize;
cdbret->ptr = dret.dptr;
+ begin_critical_section(S_DATABASE);
dtkey[CC->cs_pid] = gdbm_nextkey(gdbms[cdb], dtkey[CC->cs_pid]);
+ end_critical_section(S_DATABASE);
return(cdbret);
}