Remove ulog_check(); the ulog is not a DB journal

The db2 DB is not power-fail safe.  There's no point trying to
replay an incompletely committed entry from the ulog at kadmind
startup time.  For that matter, even if the db2 DB was power-fail
safe there'd be no point replaying an uncommitted entry from the
ulog as the libkadm5srv app (nor any client of it, as in the case of
kadmind) will not have received any notice of success -- it'd be
wrong to complete that operation later when the user thought it'd
failed.

[ghudson@mit.edu: merge with master, adjust comment]

ticket: 7552 (new)

src/lib/kdb/kdb_log.c

@@ -284,12 +284,8 @@ ulog_delete_update(krb5_context context, kdb_incr_update_t *upd)
     return ulog_add_update(context, upd);
 }
 
-/*
- * Used by the slave or master (during ulog_check) to update it's hash db from
- * the incr update log.
- *
- * Must be called with lock held.
- */
+/* Used by the slave to update its hash db from* the incr update log.  Must be
+ * called with lock held. */
 krb5_error_code
 ulog_replay(krb5_context context, kdb_incr_result_t *incr_ret, char **db_args)
 {
@@ -364,96 +360,11 @@ ulog_replay(krb5_context context, kdb_incr_result_t *incr_ret, char **db_args)
     if (fupd)
         ulog_free_entries(fupd, no_of_updates);
 
-    if (log_ctx && log_ctx->iproprole == IPROP_SLAVE) {
-        if (retval)
-            ulog_finish_update_slave(ulog, errlast);
-        else
-            ulog_finish_update_slave(ulog, incr_ret->lastentry);
-    }
-
-    return retval;
-}
-
-/*
- * Validate the log file and resync any uncommitted update entries to the
- * principal database.
- *
- * Must be called with lock held.
- */
-static krb5_error_code
-ulog_check(krb5_context context, kdb_hlog_t *ulog, char **db_args)
-{
-    XDR xdrs;
-    krb5_error_code retval = 0;
-    unsigned int i;
-    kdb_ent_header_t *indx_log;
-    kdb_incr_update_t *upd = NULL;
-    kdb_incr_result_t *incr_ret = NULL;
-
-    ulog->kdb_state = KDB_STABLE;
-
-    for (i = 0; i < ulog->kdb_num; i++) {
-        indx_log = (kdb_ent_header_t *)INDEX(ulog, i);
-
-        if (indx_log->kdb_umagic != KDB_ULOG_MAGIC) {
-            /* The update entry is corrupted; we should scream and die. */
-            ulog->kdb_state = KDB_CORRUPT;
-            retval = KRB5_LOG_CORRUPT;
-            break;
-        }
-
-        if (indx_log->kdb_commit)
-            continue;
-
-        ulog->kdb_state = KDB_UNSTABLE;
-
-        incr_ret = k5alloc(sizeof(kdb_incr_result_t), &retval);
-        if (incr_ret == NULL)
-            goto error;
-        upd = k5alloc(sizeof(kdb_incr_update_t), &retval);
-        if (upd == NULL)
-            goto error;
-
-        xdrmem_create(&xdrs, (char *)indx_log->entry_data,
-                      indx_log->kdb_entry_size, XDR_DECODE);
-        if (!xdr_kdb_incr_update_t(&xdrs, upd)) {
-            retval = KRB5_LOG_CONV;
-            goto error;
-        }
-
-        incr_ret->updates.kdb_ulog_t_len = 1;
-        incr_ret->updates.kdb_ulog_t_val = upd;
-
-        upd->kdb_commit = TRUE;
-
-        /* We don't want to re-add this update; just use the existing update to
-         * be propagated later on.  ulog_replay frees upd. */
-        ulog_set_role(context, IPROP_NULL);
-        retval = ulog_replay(context, incr_ret, db_args);
-        free(incr_ret);
-        incr_ret = NULL;
-        upd = NULL;
-        ulog_set_role(context, IPROP_MASTER);
-        if (retval)
-            goto error;
-
-        /*
-         * We flag this as committed since this was the last entry before
-         * kadmind crashed, ergo the slaves have not seen this update before.
-         */
-        indx_log->kdb_commit = TRUE;
-        retval = ulog_sync_update(ulog, indx_log);
-        if (retval)
-            goto error;
-
-        ulog->kdb_state = KDB_STABLE;
-    }
+    if (retval)
+        ulog_finish_update_slave(ulog, errlast);
+    else
+        ulog_finish_update_slave(ulog, incr_ret->lastentry);
 
-error:
-    if (upd)
-        ulog_free_entries(upd, 1);
-    free(incr_ret);
-    ulog_sync_header(ulog);
     return retval;
 }
 
@@ -609,25 +520,6 @@ ulog_map(krb5_context context, const char *logname, uint32_t ulogentries,
         return 0;
     }
 
-    if (caller == FKADMIND) {
-        switch (ulog->kdb_state) {
-        case KDB_STABLE:
-        case KDB_UNSTABLE:
-            /* Log is currently un/stable, check anyway. */
-            retval = ulog_check(context, ulog, db_args);
-            ulog_lock(context, KRB5_LOCKMODE_UNLOCK);
-            if (retval)
-                return retval;
-            break;
-        case KDB_CORRUPT:
-            ulog_lock(context, KRB5_LOCKMODE_UNLOCK);
-            return KRB5_LOG_CORRUPT;
-        default:
-            /* Invalid db state. */
-            ulog_lock(context, KRB5_LOCKMODE_UNLOCK);
-            return KRB5_LOG_ERROR;
-        }
-    }
     assert(caller == FKADMIND || caller == FKCOMMAND);
 
     /* Reinit ulog if the log is being truncated or expanded after we have