2009/323 - rpcgen error reporting

[Jordan Brown]

I am sponsoring the following for fast track approval.  The timer expires 
Thursday 4 June 2009.

PSARC 2009/323 - rpcgen error reporting

Name:           rpcgen error reporting
Submitter:      Jordan Brown
Owner:          Jordan Brown
Interest:       Robert.Thurlow at sun.com
Status:         waiting fast-track 06/04/2009
Exposure:       open

SUMMARY

     Adds a mechanism to allow an application using rpcgen-created
     server code to control how errors are reported.

BACKGROUND

     rpcgen's generated service code (*_svc.c) includes a function _msgout
     that it calls to report errors it encounters.  The application is
     provided only limited and ill-documented ways to control the operation
     of this function; it either calls syslog() or writes to standard
     error.

PROBLEM

     If the developer wants more control over error reporting it is
     necessary to statically create the file, edit it to replace
     _msgout, and check in the resulting file.  This creates an ongoing
     maintenance headache, since changes to the *.x file must be
     hand-merged into this file.

PROPOSAL

     Define a public interface allowing the developer to intercept
     message output, by allowing the use of a compile-time macro to
     specify an alternate routine.

DETAILS

     If the *_svc.c file is compiled with a macro RPC_MSGOUT defined,
     perhaps using a compiler option like -DRPC_MSGOUT=mymsgfunc,
     the value specified will be used as the name of a printf-like
     function to be called with any errors to be reported.  That
     function must conform to the signature

extern void RPC_MSGOUT(const char *fmt, ...);

COMMENTS

     The existing _msgout function takes a single argument, a message to
     be printed.  If we're making this a public interface, it seems to
     make sense to provide for future expansion, which is why this case
     proposes to define the function as a printf-like function.

     Current error reporting behavior is formally undefined.  The
     suggested manual page text below slightly defines it, by specifying
     that standard error and/or the system log are used, but avoids
     specifying how that decision is made.

DELIVERY VEHICLE

     Solaris

RELEASE

     Patch

COMMITMENT LEVEL

     Committed

TESTIMONIALS

     Rob Thurlow has reviewed this proposal and endorses it.

MANUAL PAGE

     Add to the manual page text along the lines of:

     SERVER ERROR REPORTING

         By default, errors detected by proto_svc.c will be reported to
         standard error and/or the system log.

         This behavior can be overridden by compiling the file with a
         definition of RPC_MSGOUT, e.g. -DRPC_MSGOUT=mymsgfunc.  The
         function specified will be called to report errors.  It must
         conform to this printf-like signature:

             extern void RPC_MSGOUT(const char *fmt, ...);