This patch is another step towards the promised land of 
accurately-restored tracepoint definitions.  For those just tuning in, 
the problem is that in both the disconnected tracing and the trace file 
cases, it's very difficult to use tracepoints if the definitions in GDB 
do not match up with what was used to create the trace frames on the 
target or in the file.  This patch takes a more audacious approach that 
seems to work well in practice; it literally downloads and uploads the 
original source form of the tracepoint, whitespace and all.  As freaky 
as it sounds, it works because if the source strings don't parse 
(because the executable has changed, for instance), then there is almost 
no chance that the trace frame data is going to be meaningful at the 
symbolic level.

This is not quite the end of the story, the heuristic matchup of new/old 
tracepoints still needs work, and there are some minor patches still 
queued up.  For testing, I'll add to the tfile.exp test after 
incorporating Pedro's feedback from the previous patch.  I'll hold off 
committing this for a couple days in case anybody has comments.

Stan

2010-03-25  Stan Shebs  <stan@codesourcery.com>

        * tracepoint.h (struct uploaded_string): New struct.
        (struct uploaded_tp): New fields for source strings.
        * breakpoint.c (this_utp, next_cmd): New globals.
        (read_uploaded_action): New function.
        (create_tracepoint_from_upload): Fill in more parts
        of a tracepoint.
        * tracepoint.c (encode_source_string): New function.
        (trace_save): Write out source strings, fix error checks.
        (parse_tracepoint_definition): Add source string parsing.
        * remote.c (PACKET_TracepointSource): New packet type.
        (remote_download_command_source): New function.
        (remote_download_tracepoint): Download source pieces also.
        (_initialize_remote): Add packet config command.

        * gdb.texinfo (Tracepoint Packets): Describe QTDPsrc.
        (General Query Packets): Describe TracepointSource.