added storage of extended ltdb header information

(This used to be ctdb commit a18c9411081a4e5997bf030fa924abfc33fb3310)

diff --git a/ctdb/common/ctdb_call.c b/ctdb/common/ctdb_call.c
index a2219403a2509ff2b35a724c4acad7962e2fa3b5..441e22b613c6df4a748808ef52e853e5b8e5a7a2 100644 (file)
--- a/ctdb/common/ctdb_call.c
+++ b/ctdb/common/ctdb_call.c
@@ -34,18 +34,20 @@ static int ctdb_call_local(struct ctdb_context *ctdb, TDB_DATA key, int call_id,
        struct ctdb_call *c;
        struct ctdb_registered_call *fn;
        TDB_DATA data;
+       struct ctdb_ltdb_header header;
+       int ret;
 
        c = talloc(ctdb, struct ctdb_call);
        CTDB_NO_MEMORY(ctdb, c);
 
-       data = tdb_fetch(ctdb->ltdb, key);
+       ret = ctdb_ltdb_fetch(ctdb, c, key, &header, &data);
+       if (ret != 0) return -1;
        
        c->key = key;
        c->call_data = call_data;
        c->record_data.dptr = talloc_memdup(c, data.dptr, data.dsize);
        c->record_data.dsize = data.dsize;
        CTDB_NO_MEMORY(ctdb, c->record_data.dptr);
-       if (data.dptr) free(data.dptr);
        c->new_data = NULL;
        c->reply_data = NULL;
 
@@ -58,13 +60,12 @@ static int ctdb_call_local(struct ctdb_context *ctdb, TDB_DATA key, int call_id,
        }
 
        if (fn->fn(c) != 0) {
-               free(c->record_data.dptr);
                ctdb_set_error(ctdb, "ctdb_call %u failed\n", call_id);
                return -1;
        }
 
        if (c->new_data) {
-               if (tdb_store(ctdb->ltdb, key, *c->new_data, TDB_REPLACE) != 0) {
+               if (ctdb_ltdb_store(ctdb, key, &header, *c->new_data) != 0) {
                        ctdb_set_error(ctdb, "ctdb_call tdb_store failed\n");
                        return -1;
                }

diff --git a/ctdb/common/ctdb_ltdb.c b/ctdb/common/ctdb_ltdb.c
index 4fe316f4db99fc4da65d0836c82aff74d0302260..004ab254d5d6aafc9ce6dda2601dc0f7f39973b8 100644 (file)
--- a/ctdb/common/ctdb_ltdb.c
+++ b/ctdb/common/ctdb_ltdb.c
@@ -40,3 +40,72 @@ int ctdb_attach(struct ctdb_context *ctdb, const char *name, int tdb_flags,
        }
        return 0;
 }
+
+
+/*
+  construct an initial header for a record with no ltdb header yet
+*/
+static void ltdb_initial_header(struct ctdb_context *ctdb, 
+                               TDB_DATA key,
+                               struct ctdb_ltdb_header *header)
+{
+       header->rsn = 0;
+       header->dmaster = ctdb_hash(&key) % ctdb->num_nodes;
+       header->laccessor = header->dmaster;
+       header->lacount = 0;
+}
+
+
+/*
+  fetch a record from the ltdb, separating out the header information
+  and returning the body of the record. A valid (initial) header is
+  returned if the record is not present
+*/
+int ctdb_ltdb_fetch(struct ctdb_context *ctdb, TALLOC_CTX *mem_ctx,
+                   TDB_DATA key, struct ctdb_ltdb_header *header, TDB_DATA *data)
+{
+       TDB_DATA rec;
+
+       rec = tdb_fetch(ctdb->ltdb, key);
+       if (rec.dsize < sizeof(*header)) {
+               /* return an initial header */
+               ltdb_initial_header(ctdb, key, header);
+               data->dptr = NULL;
+               data->dsize = 0;
+               return 0;
+       }
+
+       *header = *(struct ctdb_ltdb_header *)rec.dptr;
+
+       data->dsize = rec.dsize - sizeof(struct ctdb_ltdb_header);
+       data->dptr = talloc_memdup(mem_ctx, sizeof(struct ctdb_ltdb_header)+rec.dptr,
+                                  data->dsize);
+       CTDB_NO_MEMORY(ctdb, data->dptr);
+
+       return 0;
+}
+
+
+/*
+  fetch a record from the ltdb, separating out the header information
+  and returning the body of the record. A valid (initial) header is
+  returned if the record is not present
+*/
+int ctdb_ltdb_store(struct ctdb_context *ctdb, TDB_DATA key, 
+                   struct ctdb_ltdb_header *header, TDB_DATA data)
+{
+       TDB_DATA rec;
+       int ret;
+
+       rec.dsize = sizeof(struct ctdb_ltdb_header) + data.dsize;
+       rec.dptr = talloc_size(ctdb, rec.dsize);
+       CTDB_NO_MEMORY(ctdb, rec.dptr);
+
+       memcpy(rec.dptr, header, sizeof(*header));
+       memcpy(rec.dptr + sizeof(*header), data.dptr, data.dsize);
+       
+       ret = tdb_store(ctdb->ltdb, key, rec, TDB_REPLACE);
+       talloc_free(rec.dptr);
+
+       return ret;
+}

diff --git a/ctdb/include/ctdb_private.h b/ctdb/include/ctdb_private.h
index 32f258b2bf801c91c89b052fbf706bcc75801903..bbddd74b589432b906c0b24e69bcd75262bbebab 100644 (file)
--- a/ctdb/include/ctdb_private.h
+++ b/ctdb/include/ctdb_private.h
@@ -101,13 +101,26 @@ struct ctdb_context {
 /* arbitrary maximum timeout for ctdb operations */
 #define CTDB_REQ_TIMEOUT 10
 
+/*
+  the extended header for records in the ltdb
+*/
+struct ctdb_ltdb_header {
+       uint64_t rsn;
+       uint32_t dmaster;
+       uint32_t laccessor;
+       uint32_t lacount;
+};
+
 
 /*
   operation IDs
 */
 enum ctdb_operation {
        CTDB_REQ_CALL   = 0,
-       CTDB_REPLY_CALL = 1
+       CTDB_REPLY_CALL = 1,
+       CTDB_REPLY_REDIRECT = 2,
+       CTDB_REQ_DMASTER = 3,
+       CTDB_REPLY_DMASTER = 4,
 };
 
 /*
@@ -145,3 +158,9 @@ uint32_t ctdb_hash(TDB_DATA *key);
 void ctdb_request_call(struct ctdb_context *ctdb, struct ctdb_req_header *hdr);
 void ctdb_reply_call(struct ctdb_context *ctdb, struct ctdb_req_header *hdr);
 
+int ctdb_ltdb_fetch(struct ctdb_context *ctdb, TALLOC_CTX *mem_ctx,
+                   TDB_DATA key, struct ctdb_ltdb_header *header, TDB_DATA *data);
+int ctdb_ltdb_store(struct ctdb_context *ctdb, TDB_DATA key, 
+                   struct ctdb_ltdb_header *header, TDB_DATA data);
+
+