+/*
+ * $Id$
+ *
+ * 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); */
+ }
+ }
+}