"MALFORMED COMMUNICATION PACKET" ERROR

Description :- C API, "mysql_stmt_execute" fails with an
error, "malformed communication packet", even for a simple
query when prepared statments are used with libmysqld.

Analysis :- The packet size specified in
"emb_stmt_execute()" [libmysqld/lib_sql.cc] and "execute()
[libmysql/libmysql.c] should be consistent across libraries
(libmysqld/libmysql) because "mysql_stmt_execute()"
[sql/sql_prepare.cc ] is being called from both functions
depending upon the libaries (libmysqld/libmysql) used.
Currently the packet size used in "emb_stmt_execute() is 5
and in "execute()" is 9. When the C API,
"mysql_stmt_execute", is executed from an application which
is linked with libmysqld, it fails in the function
"mysql_stmt_execute()" because of incorrect packet size.
Another bug also exists in the "Protocol::net_store_data()"
[libmysqld/lib_sql.cc] due to dereferencing an undefined
"next_field" pointer which results in a segmentation fault.

Fix:-
(a)The packet size is made consistent across libmysqld
and libmysql.
(b) For the problem found internally:
Functions "prepare_for_resend(), "net_store_data()" (with
and without charset conversion) are defined seperately for
Protocol_binary class in case of embedded library.