Renamed database_sleepycat.c to database.c
authorArt Cancro <ajc@citadel.org>
Mon, 7 Jul 2008 13:20:07 +0000 (13:20 +0000)
committerArt Cancro <ajc@citadel.org>
Mon, 7 Jul 2008 13:20:07 +0000 (13:20 +0000)
because it reflects the fact that we only have one backend store available;
and because Sleepycat Software no longer exists.

citadel/configure.ac
citadel/database.c [new file with mode: 0644]
citadel/database_sleepycat.c [deleted file]

index 3a330ea8e7ad73bbbe4f7c4d6b974bd4c76df5ee..81e5eae6ac87123400f2446ba94c909c9b0c4c2b 100644 (file)
@@ -196,7 +196,7 @@ AC_ARG_ENABLE(pie, [  --enable-pie            build position-independent executa
 
 AC_ARG_WITH(pam, [  --with-pam              use PAM if present (see PAM.txt before you try this)])
 AC_ARG_WITH(kthread, [  --with-kthread          use kernel threads (on FreeBSD) (not recommended yet)])
-AC_ARG_WITH(db, [  --with-db@<:@=DIR@:>@         use Sleepycat DB 3.x @<:@DIR=/usr/local/BerkeleyDB.3.@<:@123@:>@@:>@])
+AC_ARG_WITH(db, [  --with-db@<:@=DIR@:>@         use Berkeley DB 3.x @<:@DIR=/usr/local/BerkeleyDB.3.@<:@123@:>@@:>@])
 AC_ARG_WITH(ssl,
        [  --with-ssl=PATH         Specify path to OpenSSL installation ],
        [
@@ -603,7 +603,7 @@ if test "x$with_db" != xno; then
 
        AC_CHECK_DB([db db-4.1 db-4 db4],
                    [
-                    DATABASE=database_sleepycat.c
+                    DATABASE=database.c
                    ],
                    AC_MSG_ERROR([[Can not locate a suitable Berkeley DB
                                  library.  Use --with-db=PATH to specify
diff --git a/citadel/database.c b/citadel/database.c
new file mode 100644 (file)
index 0000000..891e31f
--- /dev/null
@@ -0,0 +1,924 @@
+/*
+ * $Id$
+ *
+ * This is a data store backend for the Citadel server which uses Berkeley DB.
+ *
+ */
+
+/*****************************************************************************
+       Tunable configuration parameters for the Berkeley DB back end
+ *****************************************************************************/
+
+/* Citadel will checkpoint the db at the end of every session, but only if
+ * 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  256
+#define MAX_CHECKPOINT_MINUTES 15
+
+/*****************************************************************************/
+
+#include "sysdep.h"
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+
+#ifdef HAVE_DB_H
+#include <db.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 <libcitadel.h>
+#include "citadel.h"
+#include "server.h"
+#include "citserver.h"
+#include "database.h"
+#include "msgbase.h"
+#include "sysdep_decls.h"
+#include "threads.h"
+#include "config.h"
+#include "control.h"
+
+#include "ctdl_module.h"
+
+
+static DB *dbp[MAXCDB];                /* One DB handle for each Citadel database */
+static DB_ENV *dbenv;          /* The DB environment (global) */
+
+
+#ifdef HAVE_ZLIB
+#include <zlib.h>
+#endif
+
+
+/* Verbose logging callback */
+void cdb_verbose_log(const DB_ENV *dbenv, const char *msg)
+{
+       CtdlLogPrintf(CTDL_DEBUG, "BDB: %s\n", msg);
+}
+
+
+/* Verbose logging callback */
+void cdb_verbose_err(const DB_ENV *dbenv, const char *errpfx, const char *msg)
+{
+       CtdlLogPrintf(CTDL_ALERT, "BDB: %s\n", msg);
+}
+
+
+/* just a little helper function */
+static void txabort(DB_TXN * tid)
+{
+       int ret;
+
+       ret = tid->abort(tid);
+
+       if (ret) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_abort: %s\n",
+                       db_strerror(ret));
+               abort();
+       }
+}
+
+/* this one is even more helpful than the last. */
+static void txcommit(DB_TXN * tid)
+{
+       int ret;
+
+       ret = tid->commit(tid, 0);
+
+       if (ret) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_commit: %s\n",
+                       db_strerror(ret));
+               abort();
+       }
+}
+
+/* are you sensing a pattern yet? */
+static void txbegin(DB_TXN ** tid)
+{
+       int ret;
+
+       ret = dbenv->txn_begin(dbenv, NULL, tid, 0);
+
+       if (ret) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_begin: %s\n",
+                       db_strerror(ret));
+               abort();
+       }
+}
+
+static void dbpanic(DB_ENV * env, int errval)
+{
+       CtdlLogPrintf(CTDL_EMERG, "cdb_*: Berkeley DB panic: %d\n", errval);
+}
+
+static void cclose(DBC * cursor)
+{
+       int ret;
+
+       if ((ret = cursor->c_close(cursor))) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_*: c_close: %s\n",
+                       db_strerror(ret));
+               abort();
+       }
+}
+
+static void bailIfCursor(DBC ** cursors, const char *msg)
+{
+       int i;
+
+       for (i = 0; i < MAXCDB; i++)
+               if (cursors[i] != NULL) {
+                       CtdlLogPrintf(CTDL_EMERG,
+                               "cdb_*: cursor still in progress on cdb %02x: %s\n",
+                               i, msg);
+                       abort();
+               }
+}
+
+void check_handles(void *arg)
+{
+       if (arg != NULL) {
+               ThreadTSD *tsd = (ThreadTSD *) arg;
+
+               bailIfCursor(tsd->cursors, "in check_handles");
+
+               if (tsd->tid != NULL) {
+                       CtdlLogPrintf(CTDL_EMERG,
+                               "cdb_*: transaction still in progress!");
+                       abort();
+               }
+       }
+}
+
+void cdb_check_handles(void)
+{
+       check_handles(pthread_getspecific(ThreadKey));
+}
+
+
+/*
+ * 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) {
+               CtdlLogPrintf(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) {
+                       CtdlLogPrintf(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.
+ */
+void cdb_checkpoint(void)
+{
+       int ret;
+//     static time_t last_run = 0L;
+
+       /* 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);
+*/
+
+       CtdlLogPrintf(CTDL_DEBUG, "-- db checkpoint --\n");
+       ret = dbenv->txn_checkpoint(dbenv,
+                                   MAX_CHECKPOINT_KBYTES,
+                                   MAX_CHECKPOINT_MINUTES, 0);
+
+       if (ret != 0) {
+               CtdlLogPrintf(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 a
+ * critical section here, because there aren't any active threads
+ * manipulating the database yet.
+ */
+void open_databases(void)
+{
+       int ret;
+       int i;
+       char dbfilename[SIZ];
+       u_int32_t flags = 0;
+       int dbversion_major, dbversion_minor, dbversion_patch;
+       int current_dbversion = 0;
+
+       CtdlLogPrintf(CTDL_DEBUG, "cdb_*: open_databases() starting\n");
+       CtdlLogPrintf(CTDL_DEBUG, "Compiled db: %s\n", DB_VERSION_STRING);
+       CtdlLogPrintf(CTDL_INFO, "  Linked db: %s\n",
+               db_version(&dbversion_major, &dbversion_minor, &dbversion_patch));
+
+       current_dbversion = (dbversion_major * 1000000) + (dbversion_minor * 1000) + dbversion_patch;
+
+       CtdlLogPrintf(CTDL_DEBUG, "Calculated dbversion: %d\n", current_dbversion);
+       CtdlLogPrintf(CTDL_DEBUG, "  Previous dbversion: %d\n", CitControl.MMdbversion);
+
+       if ( (getenv("SUPPRESS_DBVERSION_CHECK") == NULL)
+          && (CitControl.MMdbversion > current_dbversion) ) {
+               CtdlLogPrintf(CTDL_EMERG, "You are attempting to run the Citadel server using a version\n"
+                                       "of Berkeley DB that is older than that which last created or\n"
+                                       "updated the database.  Because this would probably cause data\n"
+                                       "corruption or loss, the server is aborting execution now.\n");
+               exit(CTDLEXIT_DB);
+       }
+
+       CitControl.MMdbversion = current_dbversion;
+       put_control();
+
+#ifdef HAVE_ZLIB
+       CtdlLogPrintf(CTDL_INFO, "Linked zlib: %s\n", zlibVersion());
+#endif
+
+       /*
+        * 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));
+
+       CtdlLogPrintf(CTDL_DEBUG, "cdb_*: Setting up DB environment\n");
+       db_env_set_func_yield(sched_yield);
+       ret = db_env_create(&dbenv, 0);
+       if (ret) {
+               CtdlLogPrintf(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);
+       if (ret) {
+               CtdlLogPrintf(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))) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_*: set_lk_detect: %s\n",
+                       db_strerror(ret));
+               dbenv->close(dbenv, 0);
+               exit(CTDLEXIT_DB);
+       }
+
+       flags = DB_CREATE | DB_INIT_MPOOL | DB_PRIVATE | DB_INIT_TXN | DB_INIT_LOCK | DB_THREAD | DB_RECOVER;
+       CtdlLogPrintf(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) {
+               CtdlLogPrintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
+               CtdlLogPrintf(CTDL_ALERT, "Attempting recovery...\n");
+               flags |= DB_RECOVER;
+               ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
+       }
+       if (ret == DB_RUNRECOVERY) {
+               CtdlLogPrintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
+               CtdlLogPrintf(CTDL_ALERT, "Attempting catastrophic recovery...\n");
+               flags &= ~DB_RECOVER;
+               flags |= DB_RECOVER_FATAL;
+               ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
+       }
+       if (ret) {
+               CtdlLogPrintf(CTDL_DEBUG, "dbenv->open: %s\n", db_strerror(ret));
+               dbenv->close(dbenv, 0);
+               exit(CTDLEXIT_DB);
+       }
+
+       CtdlLogPrintf(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) {
+                       CtdlLogPrintf(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.
+                */
+               snprintf(dbfilename, sizeof dbfilename, "cdb.%02x", i);
+
+               ret = dbp[i]->open(dbp[i],
+                                  NULL,
+                                  dbfilename,
+                                  NULL,
+                                  DB_BTREE,
+                                  DB_CREATE | DB_AUTO_COMMIT | DB_THREAD,
+                                  0600);
+               if (ret) {
+                       CtdlLogPrintf(CTDL_EMERG, "db_open[%02x]: %s\n", i,
+                               db_strerror(ret));
+                       exit(CTDLEXIT_DB);
+               }
+       }
+
+}
+
+
+/* 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);
+                               CtdlLogPrintf(9, "chmod(%s, 0600) returned %d\n",
+                                       filename, chmod(filename, 0600)
+                               );
+                               CtdlLogPrintf(9, "chown(%s, CTDLUID, -1) returned %d\n",
+                                       filename, chown(filename, CTDLUID, (-1))
+                               );
+                       }
+               }
+               closedir(dp);
+       }
+
+       CtdlLogPrintf(CTDL_DEBUG, "open_databases() finished\n");
+
+       CtdlRegisterProtoHook(cmd_cull, "CULL", "Cull database logs");
+}
+
+
+/*
+ * 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)
+{
+       int a;
+       int ret;
+
+       ctdl_thread_internal_free_tsd();
+       
+       if ((ret = dbenv->txn_checkpoint(dbenv, 0, 0, 0))) {
+               CtdlLogPrintf(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) {
+               CtdlLogPrintf(CTDL_INFO, "Closing database %02x\n", a);
+               ret = dbp[a]->close(dbp[a], 0);
+               if (ret) {
+                       CtdlLogPrintf(CTDL_EMERG,
+                               "db_close: %s\n", db_strerror(ret));
+               }
+
+       }
+
+       /* Close the handle. */
+       ret = dbenv->close(dbenv, 0);
+       if (ret) {
+               CtdlLogPrintf(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) {
+               CtdlLogPrintf(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)
+{
+
+       DBT dkey, ddata;
+       DB_TXN *tid;
+       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));
+       dkey.size = ckeylen;
+       dkey.data = ckey;
+       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) {
+                       CtdlLogPrintf(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 */
+               if (ret) {
+                       CtdlLogPrintf(CTDL_EMERG, "cdb_store(%d): %s\n", cdb,
+                               db_strerror(ret));
+                       abort();
+               }
+#ifdef HAVE_ZLIB
+               if (compressing)
+                       free(compressed_data);
+#endif
+               return ret;
+
+       } else {
+               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 */
+                                        &ddata,        /* data */
+                                        0))) { /* flags */
+                       if (ret == DB_LOCK_DEADLOCK) {
+                               txabort(tid);
+                               goto retry;
+                       } else {
+                               CtdlLogPrintf(CTDL_EMERG, "cdb_store(%d): %s\n",
+                                       cdb, db_strerror(ret));
+                               abort();
+                       }
+               } else {
+                       txcommit(tid);
+#ifdef HAVE_ZLIB
+                       if (compressing)
+                               free(compressed_data);
+#endif
+                       return ret;
+               }
+       }
+}
+
+
+/*
+ * Delete a piece of data.  Returns 0 if the operation was successful.
+ */
+int cdb_delete(int cdb, void *key, int keylen)
+{
+
+       DBT dkey;
+       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);
+               if (ret) {
+                       CtdlLogPrintf(CTDL_EMERG, "cdb_delete(%d): %s\n", cdb,
+                               db_strerror(ret));
+                       if (ret != DB_NOTFOUND)
+                               abort();
+               }
+       } else {
+               bailIfCursor(MYCURSORS,
+                            "attempt to delete during r/o cursor");
+
+             retry:
+               txbegin(&tid);
+
+               if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0))
+                   && ret != DB_NOTFOUND) {
+                       if (ret == DB_LOCK_DEADLOCK) {
+                               txabort(tid);
+                               goto retry;
+                       } else {
+                               CtdlLogPrintf(CTDL_EMERG, "cdb_delete(%d): %s\n",
+                                       cdb, db_strerror(ret));
+                               abort();
+                       }
+               } else {
+                       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) {
+               CtdlLogPrintf(CTDL_EMERG, "localcursor: %s\n", db_strerror(ret));
+               abort();
+       }
+
+       return curs;
+}
+
+
+/*
+ * Fetch a piece of data.  If not found, returns NULL.  Otherwise, it returns
+ * a struct cdbdata which it is the caller's responsibility to free later on
+ * using the cdb_free() routine.
+ */
+struct cdbdata *cdb_fetch(int cdb, void *key, int keylen)
+{
+
+       struct cdbdata *tempcdb;
+       DBT dkey, dret;
+       int ret;
+
+       memset(&dkey, 0, sizeof(DBT));
+       dkey.size = keylen;
+       dkey.data = key;
+
+       if (MYTID != NULL) {
+               memset(&dret, 0, sizeof(DBT));
+               dret.flags = DB_DBT_MALLOC;
+               ret = dbp[cdb]->get(dbp[cdb], MYTID, &dkey, &dret, 0);
+       } else {
+               DBC *curs;
+
+               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 != 0) && (ret != DB_NOTFOUND)) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_fetch(%d): %s\n", cdb,
+                       db_strerror(ret));
+               abort();
+       }
+
+       if (ret != 0)
+               return NULL;
+       tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
+
+       if (tempcdb == NULL) {
+               CtdlLogPrintf(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.
+ *
+ * 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)
+{
+       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.
+ * (There is guaranteed to be no more than one traversal in
+ * progress per thread at any given time.)
+ */
+void cdb_rewind(int cdb)
+{
+       int ret = 0;
+
+       if (MYCURSORS[cdb] != NULL) {
+               CtdlLogPrintf(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, &MYCURSORS[cdb], 0);
+       if (ret) {
+               CtdlLogPrintf(CTDL_EMERG, "cdb_rewind: db_cursor: %s\n",
+                       db_strerror(ret));
+               abort();
+       }
+}
+
+
+/*
+ * Fetch the next item in a sequential search.  Returns a pointer to a 
+ * cdbdata structure, or NULL if we've hit the end.
+ */
+struct cdbdata *cdb_next_item(int cdb)
+{
+       DBT key, data;
+       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));
+       data.flags = DB_DBT_MALLOC;
+
+       ret = MYCURSORS[cdb]->c_get(MYCURSORS[cdb], &key, &data, DB_NEXT);
+
+       if (ret) {
+               if (ret != DB_NOTFOUND) {
+                       CtdlLogPrintf(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 *) 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)
+{
+
+       bailIfCursor(MYCURSORS,
+                    "can't begin transaction during r/o cursor");
+
+       if (MYTID != NULL) {
+               CtdlLogPrintf(CTDL_EMERG,
+                       "cdb_begin_transaction: ERROR: nested transaction\n");
+               abort();
+       }
+
+       txbegin(&MYTID);
+}
+
+void cdb_end_transaction(void)
+{
+       int i;
+
+       for (i = 0; i < MAXCDB; i++)
+               if (MYCURSORS[i] != NULL) {
+                       CtdlLogPrintf(CTDL_WARNING,
+                               "cdb_end_transaction: WARNING: cursor %d still open at transaction end\n",
+                               i);
+                       cclose(MYCURSORS[i]);
+                       MYCURSORS[i] = NULL;
+               }
+
+       if (MYTID == NULL) {
+               CtdlLogPrintf(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) {
+               CtdlLogPrintf(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 {
+                               CtdlLogPrintf(CTDL_EMERG,
+                                       "cdb_truncate(%d): %s\n", cdb,
+                                       db_strerror(ret));
+                               abort();
+                       }
+               } else {
+                       /* txcommit(tid); */
+               }
+       }
+}
diff --git a/citadel/database_sleepycat.c b/citadel/database_sleepycat.c
deleted file mode 100644 (file)
index 7b3823f..0000000
+++ /dev/null
@@ -1,924 +0,0 @@
-/*
- * $Id$
- *
- * Sleepycat (Berkeley) DB driver for Citadel
- *
- */
-
-/*****************************************************************************
-       Tunable configuration parameters for the Sleepycat DB back end
- *****************************************************************************/
-
-/* Citadel will checkpoint the db at the end of every session, but only if
- * 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  256
-#define MAX_CHECKPOINT_MINUTES 15
-
-/*****************************************************************************/
-
-#include "sysdep.h"
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <ctype.h>
-#include <string.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <dirent.h>
-
-#ifdef HAVE_DB_H
-#include <db.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 <libcitadel.h>
-#include "citadel.h"
-#include "server.h"
-#include "citserver.h"
-#include "database.h"
-#include "msgbase.h"
-#include "sysdep_decls.h"
-#include "threads.h"
-#include "config.h"
-#include "control.h"
-
-#include "ctdl_module.h"
-
-
-static DB *dbp[MAXCDB];                /* One DB handle for each Citadel database */
-static DB_ENV *dbenv;          /* The DB environment (global) */
-
-
-#ifdef HAVE_ZLIB
-#include <zlib.h>
-#endif
-
-
-/* Verbose logging callback */
-void cdb_verbose_log(const DB_ENV *dbenv, const char *msg)
-{
-       CtdlLogPrintf(CTDL_DEBUG, "BDB: %s\n", msg);
-}
-
-
-/* Verbose logging callback */
-void cdb_verbose_err(const DB_ENV *dbenv, const char *errpfx, const char *msg)
-{
-       CtdlLogPrintf(CTDL_ALERT, "BDB: %s\n", msg);
-}
-
-
-/* just a little helper function */
-static void txabort(DB_TXN * tid)
-{
-       int ret;
-
-       ret = tid->abort(tid);
-
-       if (ret) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_abort: %s\n",
-                       db_strerror(ret));
-               abort();
-       }
-}
-
-/* this one is even more helpful than the last. */
-static void txcommit(DB_TXN * tid)
-{
-       int ret;
-
-       ret = tid->commit(tid, 0);
-
-       if (ret) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_commit: %s\n",
-                       db_strerror(ret));
-               abort();
-       }
-}
-
-/* are you sensing a pattern yet? */
-static void txbegin(DB_TXN ** tid)
-{
-       int ret;
-
-       ret = dbenv->txn_begin(dbenv, NULL, tid, 0);
-
-       if (ret) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_*: txn_begin: %s\n",
-                       db_strerror(ret));
-               abort();
-       }
-}
-
-static void dbpanic(DB_ENV * env, int errval)
-{
-       CtdlLogPrintf(CTDL_EMERG, "cdb_*: Berkeley DB panic: %d\n", errval);
-}
-
-static void cclose(DBC * cursor)
-{
-       int ret;
-
-       if ((ret = cursor->c_close(cursor))) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_*: c_close: %s\n",
-                       db_strerror(ret));
-               abort();
-       }
-}
-
-static void bailIfCursor(DBC ** cursors, const char *msg)
-{
-       int i;
-
-       for (i = 0; i < MAXCDB; i++)
-               if (cursors[i] != NULL) {
-                       CtdlLogPrintf(CTDL_EMERG,
-                               "cdb_*: cursor still in progress on cdb %02x: %s\n",
-                               i, msg);
-                       abort();
-               }
-}
-
-void check_handles(void *arg)
-{
-       if (arg != NULL) {
-               ThreadTSD *tsd = (ThreadTSD *) arg;
-
-               bailIfCursor(tsd->cursors, "in check_handles");
-
-               if (tsd->tid != NULL) {
-                       CtdlLogPrintf(CTDL_EMERG,
-                               "cdb_*: transaction still in progress!");
-                       abort();
-               }
-       }
-}
-
-void cdb_check_handles(void)
-{
-       check_handles(pthread_getspecific(ThreadKey));
-}
-
-
-/*
- * 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) {
-               CtdlLogPrintf(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) {
-                       CtdlLogPrintf(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.
- */
-void cdb_checkpoint(void)
-{
-       int ret;
-//     static time_t last_run = 0L;
-
-       /* 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);
-*/
-
-       CtdlLogPrintf(CTDL_DEBUG, "-- db checkpoint --\n");
-       ret = dbenv->txn_checkpoint(dbenv,
-                                   MAX_CHECKPOINT_KBYTES,
-                                   MAX_CHECKPOINT_MINUTES, 0);
-
-       if (ret != 0) {
-               CtdlLogPrintf(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 a
- * critical section here, because there aren't any active threads
- * manipulating the database yet.
- */
-void open_databases(void)
-{
-       int ret;
-       int i;
-       char dbfilename[SIZ];
-       u_int32_t flags = 0;
-       int dbversion_major, dbversion_minor, dbversion_patch;
-       int current_dbversion = 0;
-
-       CtdlLogPrintf(CTDL_DEBUG, "cdb_*: open_databases() starting\n");
-       CtdlLogPrintf(CTDL_DEBUG, "Compiled db: %s\n", DB_VERSION_STRING);
-       CtdlLogPrintf(CTDL_INFO, "  Linked db: %s\n",
-               db_version(&dbversion_major, &dbversion_minor, &dbversion_patch));
-
-       current_dbversion = (dbversion_major * 1000000) + (dbversion_minor * 1000) + dbversion_patch;
-
-       CtdlLogPrintf(CTDL_DEBUG, "Calculated dbversion: %d\n", current_dbversion);
-       CtdlLogPrintf(CTDL_DEBUG, "  Previous dbversion: %d\n", CitControl.MMdbversion);
-
-       if ( (getenv("SUPPRESS_DBVERSION_CHECK") == NULL)
-          && (CitControl.MMdbversion > current_dbversion) ) {
-               CtdlLogPrintf(CTDL_EMERG, "You are attempting to run the Citadel server using a version\n"
-                                       "of Berkeley DB that is older than that which last created or\n"
-                                       "updated the database.  Because this would probably cause data\n"
-                                       "corruption or loss, the server is aborting execution now.\n");
-               exit(CTDLEXIT_DB);
-       }
-
-       CitControl.MMdbversion = current_dbversion;
-       put_control();
-
-#ifdef HAVE_ZLIB
-       CtdlLogPrintf(CTDL_INFO, "Linked zlib: %s\n", zlibVersion());
-#endif
-
-       /*
-        * 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));
-
-       CtdlLogPrintf(CTDL_DEBUG, "cdb_*: Setting up DB environment\n");
-       db_env_set_func_yield(sched_yield);
-       ret = db_env_create(&dbenv, 0);
-       if (ret) {
-               CtdlLogPrintf(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);
-       if (ret) {
-               CtdlLogPrintf(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))) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_*: set_lk_detect: %s\n",
-                       db_strerror(ret));
-               dbenv->close(dbenv, 0);
-               exit(CTDLEXIT_DB);
-       }
-
-       flags = DB_CREATE | DB_INIT_MPOOL | DB_PRIVATE | DB_INIT_TXN | DB_INIT_LOCK | DB_THREAD | DB_RECOVER;
-       CtdlLogPrintf(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) {
-               CtdlLogPrintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
-               CtdlLogPrintf(CTDL_ALERT, "Attempting recovery...\n");
-               flags |= DB_RECOVER;
-               ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
-       }
-       if (ret == DB_RUNRECOVERY) {
-               CtdlLogPrintf(CTDL_ALERT, "dbenv->open: %s\n", db_strerror(ret));
-               CtdlLogPrintf(CTDL_ALERT, "Attempting catastrophic recovery...\n");
-               flags &= ~DB_RECOVER;
-               flags |= DB_RECOVER_FATAL;
-               ret = dbenv->open(dbenv, ctdl_data_dir, flags, 0);
-       }
-       if (ret) {
-               CtdlLogPrintf(CTDL_DEBUG, "dbenv->open: %s\n", db_strerror(ret));
-               dbenv->close(dbenv, 0);
-               exit(CTDLEXIT_DB);
-       }
-
-       CtdlLogPrintf(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) {
-                       CtdlLogPrintf(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.
-                */
-               snprintf(dbfilename, sizeof dbfilename, "cdb.%02x", i);
-
-               ret = dbp[i]->open(dbp[i],
-                                  NULL,
-                                  dbfilename,
-                                  NULL,
-                                  DB_BTREE,
-                                  DB_CREATE | DB_AUTO_COMMIT | DB_THREAD,
-                                  0600);
-               if (ret) {
-                       CtdlLogPrintf(CTDL_EMERG, "db_open[%02x]: %s\n", i,
-                               db_strerror(ret));
-                       exit(CTDLEXIT_DB);
-               }
-       }
-
-}
-
-
-/* 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);
-                               CtdlLogPrintf(9, "chmod(%s, 0600) returned %d\n",
-                                       filename, chmod(filename, 0600)
-                               );
-                               CtdlLogPrintf(9, "chown(%s, CTDLUID, -1) returned %d\n",
-                                       filename, chown(filename, CTDLUID, (-1))
-                               );
-                       }
-               }
-               closedir(dp);
-       }
-
-       CtdlLogPrintf(CTDL_DEBUG, "open_databases() finished\n");
-
-       CtdlRegisterProtoHook(cmd_cull, "CULL", "Cull database logs");
-}
-
-
-/*
- * 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)
-{
-       int a;
-       int ret;
-
-       ctdl_thread_internal_free_tsd();
-       
-       if ((ret = dbenv->txn_checkpoint(dbenv, 0, 0, 0))) {
-               CtdlLogPrintf(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) {
-               CtdlLogPrintf(CTDL_INFO, "Closing database %02x\n", a);
-               ret = dbp[a]->close(dbp[a], 0);
-               if (ret) {
-                       CtdlLogPrintf(CTDL_EMERG,
-                               "db_close: %s\n", db_strerror(ret));
-               }
-
-       }
-
-       /* Close the handle. */
-       ret = dbenv->close(dbenv, 0);
-       if (ret) {
-               CtdlLogPrintf(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) {
-               CtdlLogPrintf(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)
-{
-
-       DBT dkey, ddata;
-       DB_TXN *tid;
-       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));
-       dkey.size = ckeylen;
-       dkey.data = ckey;
-       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) {
-                       CtdlLogPrintf(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 */
-               if (ret) {
-                       CtdlLogPrintf(CTDL_EMERG, "cdb_store(%d): %s\n", cdb,
-                               db_strerror(ret));
-                       abort();
-               }
-#ifdef HAVE_ZLIB
-               if (compressing)
-                       free(compressed_data);
-#endif
-               return ret;
-
-       } else {
-               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 */
-                                        &ddata,        /* data */
-                                        0))) { /* flags */
-                       if (ret == DB_LOCK_DEADLOCK) {
-                               txabort(tid);
-                               goto retry;
-                       } else {
-                               CtdlLogPrintf(CTDL_EMERG, "cdb_store(%d): %s\n",
-                                       cdb, db_strerror(ret));
-                               abort();
-                       }
-               } else {
-                       txcommit(tid);
-#ifdef HAVE_ZLIB
-                       if (compressing)
-                               free(compressed_data);
-#endif
-                       return ret;
-               }
-       }
-}
-
-
-/*
- * Delete a piece of data.  Returns 0 if the operation was successful.
- */
-int cdb_delete(int cdb, void *key, int keylen)
-{
-
-       DBT dkey;
-       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);
-               if (ret) {
-                       CtdlLogPrintf(CTDL_EMERG, "cdb_delete(%d): %s\n", cdb,
-                               db_strerror(ret));
-                       if (ret != DB_NOTFOUND)
-                               abort();
-               }
-       } else {
-               bailIfCursor(MYCURSORS,
-                            "attempt to delete during r/o cursor");
-
-             retry:
-               txbegin(&tid);
-
-               if ((ret = dbp[cdb]->del(dbp[cdb], tid, &dkey, 0))
-                   && ret != DB_NOTFOUND) {
-                       if (ret == DB_LOCK_DEADLOCK) {
-                               txabort(tid);
-                               goto retry;
-                       } else {
-                               CtdlLogPrintf(CTDL_EMERG, "cdb_delete(%d): %s\n",
-                                       cdb, db_strerror(ret));
-                               abort();
-                       }
-               } else {
-                       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) {
-               CtdlLogPrintf(CTDL_EMERG, "localcursor: %s\n", db_strerror(ret));
-               abort();
-       }
-
-       return curs;
-}
-
-
-/*
- * Fetch a piece of data.  If not found, returns NULL.  Otherwise, it returns
- * a struct cdbdata which it is the caller's responsibility to free later on
- * using the cdb_free() routine.
- */
-struct cdbdata *cdb_fetch(int cdb, void *key, int keylen)
-{
-
-       struct cdbdata *tempcdb;
-       DBT dkey, dret;
-       int ret;
-
-       memset(&dkey, 0, sizeof(DBT));
-       dkey.size = keylen;
-       dkey.data = key;
-
-       if (MYTID != NULL) {
-               memset(&dret, 0, sizeof(DBT));
-               dret.flags = DB_DBT_MALLOC;
-               ret = dbp[cdb]->get(dbp[cdb], MYTID, &dkey, &dret, 0);
-       } else {
-               DBC *curs;
-
-               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 != 0) && (ret != DB_NOTFOUND)) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_fetch(%d): %s\n", cdb,
-                       db_strerror(ret));
-               abort();
-       }
-
-       if (ret != 0)
-               return NULL;
-       tempcdb = (struct cdbdata *) malloc(sizeof(struct cdbdata));
-
-       if (tempcdb == NULL) {
-               CtdlLogPrintf(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.
- *
- * 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)
-{
-       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.
- * (There is guaranteed to be no more than one traversal in
- * progress per thread at any given time.)
- */
-void cdb_rewind(int cdb)
-{
-       int ret = 0;
-
-       if (MYCURSORS[cdb] != NULL) {
-               CtdlLogPrintf(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, &MYCURSORS[cdb], 0);
-       if (ret) {
-               CtdlLogPrintf(CTDL_EMERG, "cdb_rewind: db_cursor: %s\n",
-                       db_strerror(ret));
-               abort();
-       }
-}
-
-
-/*
- * Fetch the next item in a sequential search.  Returns a pointer to a 
- * cdbdata structure, or NULL if we've hit the end.
- */
-struct cdbdata *cdb_next_item(int cdb)
-{
-       DBT key, data;
-       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));
-       data.flags = DB_DBT_MALLOC;
-
-       ret = MYCURSORS[cdb]->c_get(MYCURSORS[cdb], &key, &data, DB_NEXT);
-
-       if (ret) {
-               if (ret != DB_NOTFOUND) {
-                       CtdlLogPrintf(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 *) 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)
-{
-
-       bailIfCursor(MYCURSORS,
-                    "can't begin transaction during r/o cursor");
-
-       if (MYTID != NULL) {
-               CtdlLogPrintf(CTDL_EMERG,
-                       "cdb_begin_transaction: ERROR: nested transaction\n");
-               abort();
-       }
-
-       txbegin(&MYTID);
-}
-
-void cdb_end_transaction(void)
-{
-       int i;
-
-       for (i = 0; i < MAXCDB; i++)
-               if (MYCURSORS[i] != NULL) {
-                       CtdlLogPrintf(CTDL_WARNING,
-                               "cdb_end_transaction: WARNING: cursor %d still open at transaction end\n",
-                               i);
-                       cclose(MYCURSORS[i]);
-                       MYCURSORS[i] = NULL;
-               }
-
-       if (MYTID == NULL) {
-               CtdlLogPrintf(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) {
-               CtdlLogPrintf(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 {
-                               CtdlLogPrintf(CTDL_EMERG,
-                                       "cdb_truncate(%d): %s\n", cdb,
-                                       db_strerror(ret));
-                               abort();
-                       }
-               } else {
-                       /* txcommit(tid); */
-               }
-       }
-}