X-Git-Url: https://code.citadel.org/?a=blobdiff_plain;f=citadel%2Fdatabase_sleepycat.c;h=ce21e8319c5ee41a743e6f441761378fa794275d;hb=83776a3a51b4cfb71f2ec19401b4ada9bd9ac0fd;hp=82d886e8989a4fd994a0641585e1b7d333c3751b;hpb=3291d029e1d490e5cf9d5518630d78516752eb35;p=citadel.git

diff --git a/citadel/database_sleepycat.c b/citadel/database_sleepycat.c
index 82d886e89..ce21e8319 100644
--- a/citadel/database_sleepycat.c
+++ b/citadel/database_sleepycat.c
@@ -1,7 +1,7 @@
 /*
  * $Id$
  *
- * Sleepycat (Berkeley) DB driver for Citadel/UX
+ * Sleepycat (Berkeley) DB driver for Citadel
  *
  */
 
@@ -13,7 +13,7 @@
  * the specified number of kilobytes has been written, or if the specified
  * number of minutes has passed, since the last checkpoint.
  */
-#define MAX_CHECKPOINT_KBYTES	0
+#define MAX_CHECKPOINT_KBYTES	256
 #define MAX_CHECKPOINT_MINUTES	15
 
 /*****************************************************************************/
@@ -26,108 +26,147 @@
 #include <string.h>
 #include <errno.h>
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+
+#ifdef HAVE_DB_H
 #include <db.h>
-#include <pthread.h>
+#elif defined(HAVE_DB4_DB_H)
+#include <db4/db.h>
+#else
+#error Neither <db.h> nor <db4/db.h> was found by configure. Install db4-devel.
+#endif
+
+
+#if DB_VERSION_MAJOR < 4 || DB_VERSION_MINOR < 1
+#error Citadel requires Berkeley DB v4.1 or newer.  Please upgrade.
+#endif
+
+
 #include "citadel.h"
 #include "server.h"
 #include "citserver.h"
 #include "database.h"
+#include "msgbase.h"
 #include "sysdep_decls.h"
-#include "dynloader.h"
+#include "threads.h"
+#include "config.h"
+
+#include "ctdl_module.h"
+
 
-DB *dbp[MAXCDB];		/* One DB handle for each Citadel database */
-DB_ENV *dbenv;			/* The DB environment (global) */
+static DB *dbp[MAXCDB];		/* One DB handle for each Citadel database */
+static DB_ENV *dbenv;		/* The DB environment (global) */
 
-struct cdbtsd {			/* Thread-specific DB stuff */
-	DB_TXN *tid;		/* Transaction handle */
-	DBC *cursor;		/* Cursor, for traversals... */
-};
 
-int num_ssd = 0;
+#ifdef HAVE_ZLIB
+#include <zlib.h>
+#endif
 
-static pthread_key_t tsdkey;
 
-#define MYCURSOR	(((struct cdbtsd*)pthread_getspecific(tsdkey))->cursor)
-#define MYTID		(((struct cdbtsd*)pthread_getspecific(tsdkey))->tid)
+/* Verbose logging callback */
+void cdb_verbose_log(const DB_ENV *dbenv, const char *msg)
+{
+	lprintf(CTDL_DEBUG, "BDB: %s\n", msg);
+}
+
+
+/* Verbose logging callback */
+void cdb_verbose_err(const DB_ENV *dbenv, const char *errpfx, const char *msg)
+{
+	lprintf(CTDL_ALERT, "BDB: %s\n", msg);
+}
+
 
 /* just a little helper function */
-static int txabort(DB_TXN *tid) {
-        int ret = txn_abort(tid);
+static void txabort(DB_TXN * tid)
+{
+	int ret;
 
-        if (ret)
-                lprintf(1, "txn_abort: %s\n", db_strerror(ret));
+	ret = tid->abort(tid);
 
-        return ret;
+	if (ret) {
+		lprintf(CTDL_EMERG, "cdb_*: txn_abort: %s\n",
+			db_strerror(ret));
+		abort();
+	}
 }
 
 /* this one is even more helpful than the last. */
-static int txcommit(DB_TXN *tid) {
-        int ret = txn_commit(tid, 0);
+static void txcommit(DB_TXN * tid)
+{
+	int ret;
 
-        if (ret)
-                lprintf(1, "txn_commit: %s\n", db_strerror(ret));
+	ret = tid->commit(tid, 0);
 
-        return ret;
+	if (ret) {
+		lprintf(CTDL_EMERG, "cdb_*: txn_commit: %s\n",
+			db_strerror(ret));
+		abort();
+	}
 }
 
 /* are you sensing a pattern yet? */
-static int txbegin(DB_TXN **tid) {
-        int ret = txn_begin(dbenv, NULL, tid, 0);
+static void txbegin(DB_TXN ** tid)
+{
+	int ret;
 
-        if (ret)
-                lprintf(1, "txn_begin: %s\n", db_strerror(ret));
+	ret = dbenv->txn_begin(dbenv, NULL, tid, 0);
 
-        return ret;
+	if (ret) {
+		lprintf(CTDL_EMERG, "cdb_*: txn_begin: %s\n",
+			db_strerror(ret));
+		abort();
+	}
 }
 
-static void release_handles(void *arg) {
-	if (arg != NULL) {
-		struct cdbtsd *tsd = (struct cdbtsd *)arg;
+static void dbpanic(DB_ENV * env, int errval)
+{
+	lprintf(CTDL_EMERG, "cdb_*: Berkeley DB panic: %d\n", errval);
+}
 
-		if (tsd->cursor != NULL) {
-			lprintf(1, "WARNING: cursor still in progress; "
-				"closing!\n");
-			tsd->cursor->c_close(tsd->cursor);
-		}
+static void cclose(DBC * cursor)
+{
+	int ret;
 
-		if (tsd->tid != NULL) {
-			lprintf(1, "ERROR: transaction still in progress; "
-				"aborting!\n");
-			txabort(tsd->tid);
-		}
+	if ((ret = cursor->c_close(cursor))) {
+		lprintf(CTDL_EMERG, "cdb_*: c_close: %s\n",
+			db_strerror(ret));
+		abort();
 	}
 }
 
-static void dest_tsd(void *arg) {
-	if (arg != NULL) {
-		release_handles(arg);
-		phree(arg);
-	}
+static void bailIfCursor(DBC ** cursors, const char *msg)
+{
+	int i;
+
+	for (i = 0; i < MAXCDB; i++)
+		if (cursors[i] != NULL) {
+			lprintf(CTDL_EMERG,
+				"cdb_*: cursor still in progress on cdb %d: %s\n",
+				i, msg);
+			abort();
+		}
 }
 
-/*
- * Ensure that we have a key for thread-specific data.  We don't
- * put anything in here that Citadel cares about; this is just database
- * related stuff like cursors and transactions.
- *
- * This should be called immediately after startup by any thread which wants
- * to use database calls, except for whatever thread calls open_databases.
- */
-void cdb_allocate_tsd(void) {
-	struct cdbtsd *tsd = mallok(sizeof *tsd);
+void check_handles(void *arg)
+{
+	if (arg != NULL) {
+		ThreadTSD *tsd = (ThreadTSD *) arg;
 
-	tsd->tid = NULL;
-	tsd->cursor = NULL;
-	pthread_setspecific(tsdkey, tsd);
-}
+		bailIfCursor(tsd->cursors, "in check_handles");
 
-void cdb_free_tsd(void) {
-	dest_tsd(pthread_getspecific(tsdkey));
-	pthread_setspecific(tsdkey, NULL);
+		if (tsd->tid != NULL) {
+			lprintf(CTDL_EMERG,
+				"cdb_*: transaction still in progress!");
+			abort();
+		}
+	}
 }
 
-void cdb_release_handles(void) {
-	release_handles(pthread_getspecific(tsdkey));
+void cdb_check_handles(void)
+{
+	check_handles(pthread_getspecific(ThreadKey));
 }
 
 
@@ -144,27 +183,97 @@ void defrag_databases(void)
 }
 
 
+/*
+ * Cull the database logs
+ */
+static void cdb_cull_logs(void)
+{
+	u_int32_t flags;
+	int ret;
+	char **file, **list;
+	char errmsg[SIZ];
+
+	flags = DB_ARCH_ABS;
+
+	/* Get the list of names. */
+	if ((ret = dbenv->log_archive(dbenv, &list, flags)) != 0) {
+		lprintf(CTDL_ERR, "cdb_cull_logs: %s\n", db_strerror(ret));
+		return;
+	}
+
+	/* Print the list of names. */
+	if (list != NULL) {
+		for (file = list; *file != NULL; ++file) {
+			lprintf(CTDL_DEBUG, "Deleting log: %s\n", *file);
+			ret = unlink(*file);
+			if (ret != 0) {
+				snprintf(errmsg, sizeof(errmsg),
+					 " ** ERROR **\n \n \n "
+					 "Citadel was unable to delete the "
+					 "database log file '%s' because of the "
+					 "following error:\n \n %s\n \n"
+					 " This log file is no longer in use "
+					 "and may be safely deleted.\n",
+					 *file, strerror(errno));
+				aide_message(errmsg, "Database Warning Message");
+			}
+		}
+		free(list);
+	}
+}
+
+/*
+ * Manually initiate log file cull.
+ */
+void cmd_cull(char *argbuf) {
+	if (CtdlAccessCheck(ac_internal)) return;
+	cdb_cull_logs();
+	cprintf("%d Database log file cull completed.\n", CIT_OK);
+}
+
 
 /*
  * Request a checkpoint of the database.
  */
-static void cdb_checkpoint(void) {
+void cdb_checkpoint(void)
+{
 	int ret;
+//	static time_t last_run = 0L;
 
-	ret = txn_checkpoint(dbenv,
-				MAX_CHECKPOINT_KBYTES,
-				MAX_CHECKPOINT_MINUTES,
-				0);
-	if (ret) {
-		lprintf(1, "txn_checkpoint: %s\n", db_strerror(ret));
+	/* Only do a checkpoint once per minute. */
+/*
+ * Don't need this any more, since the thread that calls us sleeps for 60 seconds between calls
+ 
+	if ((time(NULL) - last_run) < 60L) {
+		return;
+	}
+	last_run = time(NULL);
+*/
+
+	lprintf(CTDL_DEBUG, "-- db checkpoint --\n");
+	ret = dbenv->txn_checkpoint(dbenv,
+				    MAX_CHECKPOINT_KBYTES,
+				    MAX_CHECKPOINT_MINUTES, 0);
+
+	if (ret != 0) {
+		lprintf(CTDL_EMERG, "cdb_checkpoint: txn_checkpoint: %s\n",
+			db_strerror(ret));
+		abort();
+	}
+
+	/* After a successful checkpoint, we can cull the unused logs */
+	if (config.c_auto_cull) {
+		cdb_cull_logs();
 	}
 }
 
+
+
 /*
  * Open the various databases we'll be using.  Any database which
- * does not exist should be created.  Note that we don't need an S_DATABASE
- * critical section here, because there aren't any active threads manipulating
- * the database yet -- and besides, it causes problems on BSDI.
+ * does not exist should be created.  Note that we don't need a
+ * critical section here, because there aren't any active threads
+ * manipulating the database yet.
  */
 void open_databases(void)
 {
@@ -173,90 +282,149 @@ void open_databases(void)
 	char dbfilename[SIZ];
 	u_int32_t flags = 0;
 
-	lprintf(9, "open_databases() starting\n");
-        /*
-         * Silently try to create the database subdirectory.  If it's
-         * already there, no problem.
-         */
-        system("exec mkdir data 2>/dev/null");
+	lprintf(CTDL_DEBUG, "cdb_*: open_databases() starting\n");
+	lprintf(CTDL_DEBUG, "Compiled db: %s\n", DB_VERSION_STRING);
+	lprintf(CTDL_INFO, "  Linked db: %s\n",
+		db_version(NULL, NULL, NULL));
+#ifdef HAVE_ZLIB
+	lprintf(CTDL_INFO, "Linked zlib: %s\n", zlibVersion());
+#endif
 
-	lprintf(9, "Setting up DB environment\n");
+	/*
+	 * Silently try to create the database subdirectory.  If it's
+	 * already there, no problem.
+	 */
+	mkdir(ctdl_data_dir, 0700);
+	chmod(ctdl_data_dir, 0700);
+	chown(ctdl_data_dir, CTDLUID, (-1));
+
+	lprintf(CTDL_DEBUG, "cdb_*: Setting up DB environment\n");
 	db_env_set_func_yield(sched_yield);
 	ret = db_env_create(&dbenv, 0);
 	if (ret) {
-		lprintf(1, "db_env_create: %s\n", db_strerror(ret));
-		exit(ret);
+		lprintf(CTDL_EMERG, "cdb_*: db_env_create: %s\n",
+			db_strerror(ret));
+		exit(CTDLEXIT_DB);
 	}
 	dbenv->set_errpfx(dbenv, "citserver");
+	dbenv->set_paniccall(dbenv, dbpanic);
+	dbenv->set_errcall(dbenv, cdb_verbose_err);
+	dbenv->set_errpfx(dbenv, "ctdl");
+#if (DB_VERSION_MAJOR == 4) && (DB_VERSION_MINOR >= 3)
+	dbenv->set_msgcall(dbenv, cdb_verbose_log);
+#endif
+	dbenv->set_verbose(dbenv, DB_VERB_DEADLOCK, 1);
+	dbenv->set_verbose(dbenv, DB_VERB_RECOVERY, 1);
 
-        /*
-         * We want to specify the shared memory buffer pool cachesize,
-         * but everything else is the default.
-         */
-        ret = dbenv->set_cachesize(dbenv, 0, 64 * 1024, 0);
+	/*
+	 * We want to specify the shared memory buffer pool cachesize,
+	 * but everything else is the default.
+	 */
+	ret = dbenv->set_cachesize(dbenv, 0, 64 * 1024, 0);
 	if (ret) {
-		lprintf(1, "set_cachesize: %s\n", db_strerror(ret));
-                dbenv->close(dbenv, 0);
-                exit(ret);
-        }
+		lprintf(CTDL_EMERG, "cdb_*: set_cachesize: %s\n",
+			db_strerror(ret));
+		dbenv->close(dbenv, 0);
+		exit(CTDLEXIT_DB);
+	}
 
 	if ((ret = dbenv->set_lk_detect(dbenv, DB_LOCK_DEFAULT))) {
-		lprintf(1, "set_lk_detect: %s\n", db_strerror(ret));
+		lprintf(CTDL_EMERG, "cdb_*: set_lk_detect: %s\n",
+			db_strerror(ret));
 		dbenv->close(dbenv, 0);
-		exit(ret);
+		exit(CTDLEXIT_DB);
 	}
 
-        flags = DB_CREATE|DB_RECOVER|DB_INIT_MPOOL|DB_PRIVATE|DB_INIT_TXN|
-		DB_INIT_LOCK|DB_THREAD;
-        ret = dbenv->open(dbenv, "./data", flags, 0);
+	flags = DB_CREATE | DB_INIT_MPOOL | DB_PRIVATE | DB_INIT_TXN | DB_INIT_LOCK | DB_THREAD | DB_RECOVER;
+	lprintf(CTDL_DEBUG, "dbenv->open(dbenv, %s, %d, 0)\n", ctdl_data_dir, flags);
+	ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
+	if (ret == DB_RUNRECOVERY) {
+		lprintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
+		lprintf(CTDL_ALERT, "Attempting recovery...\n");
+		flags |= DB_RECOVER;
+		ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
+	}
+	if (ret == DB_RUNRECOVERY) {
+		lprintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
+		lprintf(CTDL_ALERT, "Attempting catastrophic recovery...\n");
+		flags &= ~DB_RECOVER;
+		flags |= DB_RECOVER_FATAL;
+		ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
+	}
 	if (ret) {
-		lprintf(1, "dbenv->open: %s\n", db_strerror(ret));
-                dbenv->close(dbenv, 0);
-                exit(ret);
-        }
+		lprintf(CTDL_DEBUG, "dbenv->open: %s\n", db_strerror(ret));
+		dbenv->close(dbenv, 0);
+		exit(CTDLEXIT_DB);
+	}
 
-	lprintf(7, "Starting up DB\n");
+	lprintf(CTDL_INFO, "Starting up DB\n");
 
 	for (i = 0; i < MAXCDB; ++i) {
 
 		/* Create a database handle */
 		ret = db_create(&dbp[i], dbenv, 0);
 		if (ret) {
-			lprintf(1, "db_create: %s\n", db_strerror(ret));
-			exit(ret);
+			lprintf(CTDL_DEBUG, "db_create: %s\n",
+				db_strerror(ret));
+			exit(CTDLEXIT_DB);
 		}
 
 
 		/* Arbitrary names for our tables -- we reference them by
 		 * number, so we don't have string names for them.
 		 */
-		sprintf(dbfilename, "cdb.%02x", i);
+		snprintf(dbfilename, sizeof dbfilename, "cdb.%02x", i);
 
 		ret = dbp[i]->open(dbp[i],
-				dbfilename,
-				NULL,
-				DB_BTREE,
-				DB_CREATE,
-				0600);
+				   NULL,
+				   dbfilename,
+				   NULL,
+				   DB_BTREE,
+				   DB_CREATE | DB_AUTO_COMMIT | DB_THREAD,
+				   0600);
 		if (ret) {
-			lprintf(1, "db_open[%d]: %s\n", i, db_strerror(ret));
-			exit(ret);
+			lprintf(CTDL_EMERG, "db_open[%d]: %s\n", i,
+				db_strerror(ret));
+			exit(CTDLEXIT_DB);
 		}
 	}
 
-	if ((ret = pthread_key_create(&tsdkey, dest_tsd))) {
-		lprintf(1, "pthread_key_create: %s\n", strerror(ret));
-		exit(1);
+}
+
+
+/* Make sure we own all the files, because in a few milliseconds
+ * we're going to drop root privs.
+ */
+void cdb_chmod_data(void) {
+	DIR *dp;
+	struct dirent *d;
+	char filename[PATH_MAX];
+
+	dp = opendir(ctdl_data_dir);
+	if (dp != NULL) {
+		while (d = readdir(dp), d != NULL) {
+			if (d->d_name[0] != '.') {
+				snprintf(filename, sizeof filename,
+					 "%s/%s", ctdl_data_dir, d->d_name);
+				lprintf(9, "chmod(%s, 0600) returned %d\n",
+					filename, chmod(filename, 0600)
+				);
+				lprintf(9, "chown(%s, CTDLUID, -1) returned %d\n",
+					filename, chown(filename, CTDLUID, (-1))
+				);
+			}
+		}
+		closedir(dp);
 	}
 
-	cdb_allocate_tsd();
-	CtdlRegisterSessionHook(cdb_checkpoint, EVT_TIMER);
-	lprintf(9, "open_databases() finished\n");
+	lprintf(CTDL_DEBUG, "open_databases() finished\n");
+
+	CtdlRegisterProtoHook(cmd_cull, "CULL", "Cull database logs");
 }
 
 
 /*
- * Close all of the gdbm database files we've opened.  This can be done
+ * Close all of the db database files we've opened.  This can be done
  * in a loop, since it's just a bunch of closes.
  */
 void close_databases(void)
@@ -264,40 +432,102 @@ void close_databases(void)
 	int a;
 	int ret;
 
-	cdb_free_tsd();
-
-	if ((ret = txn_checkpoint(dbenv, 0, 0, 0))) {
-		lprintf(1, "txn_checkpoint: %s\n", db_strerror(ret));
+	ctdl_thread_internal_free_tsd();
+	
+	if ((ret = dbenv->txn_checkpoint(dbenv, 0, 0, 0))) {
+		lprintf(CTDL_EMERG,
+			"txn_checkpoint: %s\n", db_strerror(ret));
 	}
 
+	/* print some statistics... */
+#ifdef DB_STAT_ALL
+	dbenv->lock_stat_print(dbenv, DB_STAT_ALL);
+#endif
+
+	/* close the tables */
 	for (a = 0; a < MAXCDB; ++a) {
-		lprintf(7, "Closing database %d\n", a);
+		lprintf(CTDL_INFO, "Closing database %d\n", a);
 		ret = dbp[a]->close(dbp[a], 0);
 		if (ret) {
-			lprintf(1, "db_close: %s\n", db_strerror(ret));
+			lprintf(CTDL_EMERG,
+				"db_close: %s\n", db_strerror(ret));
 		}
-		
+
 	}
 
-        /* Close the handle. */
-        ret = dbenv->close(dbenv, 0);
+	/* Close the handle. */
+	ret = dbenv->close(dbenv, 0);
 	if (ret) {
-                lprintf(1, "DBENV->close: %s\n", db_strerror(ret));
-        }
+		lprintf(CTDL_EMERG,
+			"DBENV->close: %s\n", db_strerror(ret));
+	}
+}
+
+
+/*
+ * Compression functions only used if we have zlib
+ */
+#ifdef HAVE_ZLIB
+
+void cdb_decompress_if_necessary(struct cdbdata *cdb)
+{
+	static int magic = COMPRESS_MAGIC;
+	struct CtdlCompressHeader zheader;
+	char *uncompressed_data;
+	char *compressed_data;
+	uLongf destLen, sourceLen;
+
+	if (cdb == NULL)
+		return;
+	if (cdb->ptr == NULL)
+		return;
+	if (memcmp(cdb->ptr, &magic, sizeof(magic)))
+		return;
+
+	/* At this point we know we're looking at a compressed item. */
+	memcpy(&zheader, cdb->ptr, sizeof(struct CtdlCompressHeader));
+
+	compressed_data = cdb->ptr;
+	compressed_data += sizeof(struct CtdlCompressHeader);
+
+	sourceLen = (uLongf) zheader.compressed_len;
+	destLen = (uLongf) zheader.uncompressed_len;
+	uncompressed_data = malloc(zheader.uncompressed_len);
+
+	if (uncompress((Bytef *) uncompressed_data,
+		       (uLongf *) & destLen,
+		       (const Bytef *) compressed_data,
+		       (uLong) sourceLen) != Z_OK) {
+		lprintf(CTDL_EMERG, "uncompress() error\n");
+		abort();
+	}
+
+	free(cdb->ptr);
+	cdb->len = (size_t) destLen;
+	cdb->ptr = uncompressed_data;
 }
 
+#endif				/* HAVE_ZLIB */
+
+
 /*
  * Store a piece of data.  Returns 0 if the operation was successful.  If a
  * key already exists it should be overwritten.
  */
-int cdb_store(int cdb,
-	      void *ckey, int ckeylen,
-	      void *cdata, int cdatalen)
+int cdb_store(int cdb, void *ckey, int ckeylen, void *cdata, int cdatalen)
 {
 
 	DBT dkey, ddata;
 	DB_TXN *tid;
-	int ret;
+	int ret = 0;
+
+#ifdef HAVE_ZLIB
+	struct CtdlCompressHeader zheader;
+	char *compressed_data = NULL;
+	int compressing = 0;
+	size_t buffer_len = 0;
+	uLongf destLen = 0;
+#endif
 
 	memset(&dkey, 0, sizeof(DBT));
 	memset(&ddata, 0, sizeof(DBT));
@@ -306,40 +536,77 @@ int cdb_store(int cdb,
 	ddata.size = cdatalen;
 	ddata.data = cdata;
 
+#ifdef HAVE_ZLIB
+	/* Only compress Visit records.  Everything else is uncompressed. */
+	if (cdb == CDB_VISIT) {
+		compressing = 1;
+		zheader.magic = COMPRESS_MAGIC;
+		zheader.uncompressed_len = cdatalen;
+		buffer_len = ((cdatalen * 101) / 100) + 100
+		    + sizeof(struct CtdlCompressHeader);
+		destLen = (uLongf) buffer_len;
+		compressed_data = malloc(buffer_len);
+		if (compress2((Bytef *) (compressed_data +
+					 sizeof(struct
+						CtdlCompressHeader)),
+			      &destLen, (Bytef *) cdata, (uLongf) cdatalen,
+			      1) != Z_OK) {
+			lprintf(CTDL_EMERG, "compress2() error\n");
+			abort();
+		}
+		zheader.compressed_len = (size_t) destLen;
+		memcpy(compressed_data, &zheader,
+		       sizeof(struct CtdlCompressHeader));
+		ddata.size = (size_t) (sizeof(struct CtdlCompressHeader) +
+				       zheader.compressed_len);
+		ddata.data = compressed_data;
+	}
+#endif
+
 	if (MYTID != NULL) {
-		ret = dbp[cdb]->put(dbp[cdb],		/* db */
-					MYTID,		/* transaction ID */
-					&dkey,		/* key */
-					&ddata,		/* data */
-					0);		/* flags */
+		ret = dbp[cdb]->put(dbp[cdb],	/* db */
+				    MYTID,	/* transaction ID */
+				    &dkey,	/* key */
+				    &ddata,	/* data */
+				    0);	/* flags */
 		if (ret) {
-			lprintf(1, "cdb_store(%d): %s\n", cdb,
+			lprintf(CTDL_EMERG, "cdb_store(%d): %s\n", cdb,
 				db_strerror(ret));
+			abort();
 		}
+#ifdef HAVE_ZLIB
+		if (compressing)
+			free(compressed_data);
+#endif
 		return ret;
+
 	} else {
-	    retry:
-		if (txbegin(&tid))
-			return -1;
+		bailIfCursor(MYCURSORS,
+			     "attempt to write during r/o cursor");
+
+	      retry:
+		txbegin(&tid);
 
 		if ((ret = dbp[cdb]->put(dbp[cdb],	/* db */
-					 tid,		/* transaction ID */
-					 &dkey,		/* key */
+					 tid,	/* transaction ID */
+					 &dkey,	/* key */
 					 &ddata,	/* data */
-					 0))) {		/* flags */
+					 0))) {	/* flags */
 			if (ret == DB_LOCK_DEADLOCK) {
-				if (txabort(tid))
-					return ret;
-				else
-					goto retry;
-			} else {
-				lprintf(1, "cdb_store(%d): %s\n", cdb,
-					db_strerror(ret));
 				txabort(tid);
-				return ret;
+				goto retry;
+			} else {
+				lprintf(CTDL_EMERG, "cdb_store(%d): %s\n",
+					cdb, db_strerror(ret));
+				abort();
 			}
 		} else {
-			return txcommit(tid);
+			txcommit(tid);
+#ifdef HAVE_ZLIB
+			if (compressing)
+				free(compressed_data);
+#endif
+			return ret;
 		}
 	}
 }
@@ -355,36 +622,61 @@ int cdb_delete(int cdb, void *key, int keylen)
 	DB_TXN *tid;
 	int ret;
 
+	memset(&dkey, 0, sizeof dkey);
 	dkey.size = keylen;
 	dkey.data = key;
 
 	if (MYTID != NULL) {
 		ret = dbp[cdb]->del(dbp[cdb], MYTID, &dkey, 0);
-		return (ret);
+		if (ret) {
+			lprintf(CTDL_EMERG, "cdb_delete(%d): %s\n", cdb,
+				db_strerror(ret));
+			if (ret != DB_NOTFOUND)
+				abort();
+		}
 	} else {
-	    retry:
-		if (txbegin(&tid))
-			return -1;
+		bailIfCursor(MYCURSORS,
+			     "attempt to delete during r/o cursor");
 
-		if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0))) {
+	      retry:
+		txbegin(&tid);
+
+		if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0))
+		    && ret != DB_NOTFOUND) {
 			if (ret == DB_LOCK_DEADLOCK) {
-					if (txabort(tid))
-						return ret;
-					else
-						goto retry;
-			} else {
-				lprintf(1, "cdb_store(%d): %s\n", cdb,
-					db_strerror(ret));
 				txabort(tid);
-				return ret;
+				goto retry;
+			} else {
+				lprintf(CTDL_EMERG, "cdb_delete(%d): %s\n",
+					cdb, db_strerror(ret));
+				abort();
 			}
 		} else {
-			return txcommit(tid);
+			txcommit(tid);
 		}
 	}
+	return ret;
 }
 
+static DBC *localcursor(int cdb)
+{
+	int ret;
+	DBC *curs;
+
+	if (MYCURSORS[cdb] == NULL)
+		ret = dbp[cdb]->cursor(dbp[cdb], MYTID, &curs, 0);
+	else
+		ret =
+		    MYCURSORS[cdb]->c_dup(MYCURSORS[cdb], &curs,
+					  DB_POSITION);
+
+	if (ret) {
+		lprintf(CTDL_EMERG, "localcursor: %s\n", db_strerror(ret));
+		abort();
+	}
 
+	return curs;
+}
 
 
 /*
@@ -397,57 +689,80 @@ struct cdbdata *cdb_fetch(int cdb, void *key, int keylen)
 
 	struct cdbdata *tempcdb;
 	DBT dkey, dret;
-	DB_TXN *tid;
 	int ret;
 
 	memset(&dkey, 0, sizeof(DBT));
-	memset(&dret, 0, sizeof(DBT));
 	dkey.size = keylen;
 	dkey.data = key;
-	dret.flags = DB_DBT_MALLOC;
 
 	if (MYTID != NULL) {
+		memset(&dret, 0, sizeof(DBT));
+		dret.flags = DB_DBT_MALLOC;
 		ret = dbp[cdb]->get(dbp[cdb], MYTID, &dkey, &dret, 0);
 	} else {
-	    retry:
-		if (txbegin(&tid))
-			return NULL;
+		DBC *curs;
 
-		ret = dbp[cdb]->get(dbp[cdb], tid, &dkey, &dret, 0);
+		do {
+			memset(&dret, 0, sizeof(DBT));
+			dret.flags = DB_DBT_MALLOC;
+
+			curs = localcursor(cdb);
+
+			ret = curs->c_get(curs, &dkey, &dret, DB_SET);
+			cclose(curs);
+		}
+		while (ret == DB_LOCK_DEADLOCK);
 
-		if (ret == DB_LOCK_DEADLOCK) {
-			if (txabort(tid))
-				return NULL;
-			else
-				goto retry;
-		} else if (txcommit(tid))
-			return NULL;
 	}
 
 	if ((ret != 0) && (ret != DB_NOTFOUND)) {
-		lprintf(1, "cdb_fetch: %s\n", db_strerror(ret));
+		lprintf(CTDL_EMERG, "cdb_fetch(%d): %s\n", cdb,
+			db_strerror(ret));
+		abort();
 	}
-	if (ret != 0) return NULL;
-	tempcdb = (struct cdbdata *) mallok(sizeof(struct cdbdata));
+
+	if (ret != 0)
+		return NULL;
+	tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
+
 	if (tempcdb == NULL) {
-		lprintf(2, "Cannot allocate memory!\n");
+		lprintf(CTDL_EMERG,
+			"cdb_fetch: Cannot allocate memory for tempcdb\n");
+		abort();
 	}
+
 	tempcdb->len = dret.size;
 	tempcdb->ptr = dret.data;
+#ifdef HAVE_ZLIB
+	cdb_decompress_if_necessary(tempcdb);
+#endif
 	return (tempcdb);
 }
 
 
 /*
- * Free a cdbdata item (ok, this is really no big deal, but we might need to do
- * more complex stuff with other database managers in the future).
+ * Free a cdbdata item.
+ *
+ * Note that we only free the 'ptr' portion if it is not NULL.  This allows
+ * other code to assume ownership of that memory simply by storing the
+ * pointer elsewhere and then setting 'ptr' to NULL.  cdb_free() will then
+ * avoid freeing it.
  */
 void cdb_free(struct cdbdata *cdb)
 {
-	phree(cdb->ptr);
-	phree(cdb);
+	if (cdb->ptr) {
+		free(cdb->ptr);
+	}
+	free(cdb);
 }
 
+void cdb_close_cursor(int cdb)
+{
+	if (MYCURSORS[cdb] != NULL)
+		cclose(MYCURSORS[cdb]);
+
+	MYCURSORS[cdb] = NULL;
+}
 
 /* 
  * Prepare for a sequential search of an entire database.
@@ -458,20 +773,22 @@ void cdb_rewind(int cdb)
 {
 	int ret = 0;
 
-	if (MYCURSOR != NULL)
-		MYCURSOR->c_close(MYCURSOR);
-
-	if (MYTID == NULL) {
-		lprintf(1, "ERROR: cursor use outside transaction\n");
+	if (MYCURSORS[cdb] != NULL) {
+		lprintf(CTDL_EMERG,
+			"cdb_rewind: must close cursor on database %d before reopening.\n",
+			cdb);
 		abort();
+		/* cclose(MYCURSORS[cdb]); */
 	}
 
 	/*
 	 * Now initialize the cursor
 	 */
-	ret = dbp[cdb]->cursor(dbp[cdb], MYTID, &MYCURSOR, 0);
+	ret = dbp[cdb]->cursor(dbp[cdb], MYTID, &MYCURSORS[cdb], 0);
 	if (ret) {
-		lprintf(1, "db_cursor: %s\n", db_strerror(ret));
+		lprintf(CTDL_EMERG, "cdb_rewind: db_cursor: %s\n",
+			db_strerror(ret));
+		abort();
 	}
 }
 
@@ -486,51 +803,113 @@ struct cdbdata *cdb_next_item(int cdb)
 	struct cdbdata *cdbret;
 	int ret = 0;
 
-        /* Initialize the key/data pair so the flags aren't set. */
-        memset(&key, 0, sizeof(key));
-        memset(&data, 0, sizeof(data));
+	/* Initialize the key/data pair so the flags aren't set. */
+	memset(&key, 0, sizeof(key));
+	memset(&data, 0, sizeof(data));
 	data.flags = DB_DBT_MALLOC;
 
-	ret = MYCURSOR->c_get(MYCURSOR,
-		&key, &data, DB_NEXT);
-	
+	ret = MYCURSORS[cdb]->c_get(MYCURSORS[cdb], &key, &data, DB_NEXT);
+
 	if (ret) {
-		MYCURSOR->c_close(MYCURSOR);
-		MYCURSOR = NULL;
-		return NULL;		/* presumably, end of file */
+		if (ret != DB_NOTFOUND) {
+			lprintf(CTDL_EMERG, "cdb_next_item(%d): %s\n",
+				cdb, db_strerror(ret));
+			abort();
+		}
+		cclose(MYCURSORS[cdb]);
+		MYCURSORS[cdb] = NULL;
+		return NULL;	/* presumably, end of file */
 	}
 
-	cdbret = (struct cdbdata *) mallok(sizeof(struct cdbdata));
+	cdbret = (struct cdbdata *) malloc(sizeof(struct cdbdata));
 	cdbret->len = data.size;
 	cdbret->ptr = data.data;
+#ifdef HAVE_ZLIB
+	cdb_decompress_if_necessary(cdbret);
+#endif
 
 	return (cdbret);
 }
 
 
+
 /*
  * Transaction-based stuff.  I'm writing this as I bake cookies...
  */
 
-void cdb_begin_transaction(void) {
+void cdb_begin_transaction(void)
+{
+
+	bailIfCursor(MYCURSORS,
+		     "can't begin transaction during r/o cursor");
 
-	if (MYTID != NULL) {	/* FIXME this slows it down, take it out */
-		lprintf(1, "ERROR: opening a new transaction with one already open!\n");
+	if (MYTID != NULL) {
+		lprintf(CTDL_EMERG,
+			"cdb_begin_transaction: ERROR: nested transaction\n");
 		abort();
 	}
-	else {
-		txbegin(&MYTID);
-	}
+
+	txbegin(&MYTID);
 }
 
-void cdb_end_transaction(void) {
-	if (MYCURSOR != NULL) {
-		lprintf(1, "WARNING: cursor still open at transaction end\n");
-		MYCURSOR->c_close(MYCURSOR);
-		MYCURSOR = NULL;
-	}
-	if (MYTID == NULL) lprintf(1, "ERROR: txcommit(NULL) !!\n");
-	else txcommit(MYTID);
+void cdb_end_transaction(void)
+{
+	int i;
+
+	for (i = 0; i < MAXCDB; i++)
+		if (MYCURSORS[i] != NULL) {
+			lprintf(CTDL_WARNING,
+				"cdb_end_transaction: WARNING: cursor %d still open at transaction end\n",
+				i);
+			cclose(MYCURSORS[i]);
+			MYCURSORS[i] = NULL;
+		}
+
+	if (MYTID == NULL) {
+		lprintf(CTDL_EMERG,
+			"cdb_end_transaction: ERROR: txcommit(NULL) !!\n");
+		abort();
+	} else
+		txcommit(MYTID);
+
 	MYTID = NULL;
 }
 
+/*
+ * Truncate (delete every record)
+ */
+void cdb_trunc(int cdb)
+{
+	/* DB_TXN *tid; */
+	int ret;
+	u_int32_t count;
+
+	if (MYTID != NULL) {
+		lprintf(CTDL_EMERG,
+			"cdb_trunc must not be called in a transaction.\n");
+		abort();
+	} else {
+		bailIfCursor(MYCURSORS,
+			     "attempt to write during r/o cursor");
+
+	      retry:
+		/* txbegin(&tid); */
+
+		if ((ret = dbp[cdb]->truncate(dbp[cdb],	/* db */
+					      NULL,	/* transaction ID */
+					      &count,	/* #rows deleted */
+					      0))) {	/* flags */
+			if (ret == DB_LOCK_DEADLOCK) {
+				/* txabort(tid); */
+				goto retry;
+			} else {
+				lprintf(CTDL_EMERG,
+					"cdb_truncate(%d): %s\n", cdb,
+					db_strerror(ret));
+				abort();
+			}
+		} else {
+			/* txcommit(tid); */
+		}
+	}
+}