Add trace file support.

	Add trace file support.
	* tracepoint.h (enum trace_stop_reason): New enum.
	(struct trace_status): New struct.
	(parse_trace_status): Declare.
	(struct uploaded_tp): Move here from remote.c,
	add fields for actions.
	(struct uploaded_tsv): New struct.
	* tracepoint.c (tfile_ops): New target vector.
	(trace_fd): New global.
	(tfile_open): New function.
	(tfile_close): New function.
	(tfile_files_info): New function.
	(tfile_get_trace_status): New function.
	(tfile_get_traceframe_address): New function.
	(tfile_trace_find): New function.
	(tfile_fetch_registers): New function.
	(tfile_xfer_partial): New function.
	(tfile_get_trace_state_variable_value): New function.
	(init_tfile_ops): New function.
	(_initialize_tracepoint): Call it, add tfile target.
	(trace_status): New global.
	(current_trace_status): New function.
	(trace_running_p): Remove, change all users to get from
	current_trace_status()->running.
	(get_trace_status): Remove.
	(trace_status_command): Call target_get_trace_status directly,
	report more detail including tracing stop reasons.
	(trace_find_command): Always allow tfind on a file.
	(trace_find_pc_command): Ditto.
	(trace_find_tracepoint_command): Ditto.
	(trace_find_line_command): Ditto.
	(trace_find_range_command): Ditto.
	(trace_find_outside_command): Ditto.
	(trace_frames_offset, cur_offset): Declare as off_t.
	(trace_regblock_size): Rename from reg_size, update users.
	(parse_trace_status): New function.
	(tfile_interp_line): New function.
	(disconnect_or_stop_tracing): Ensure current trace
	status before asking what to do.
	(stop_reason_names): New global.
	(trace_save_command): New command.
	(get_uploaded_tp): Move here from remote.c.
	(find_matching_tracepoint): Ditto.
	(merge_uploaded_tracepoints): New function.
	(parse_trace_status): Use stop_reason_names.
	(_initialize_tracepoint): Define tsave command.
	* target.h (target_ops): New fields to_save_trace_data,
	to_upload_tracepoints, to_upload_trace_state_variables,
	to_get_raw_trace_data, change to_get_trace_status
	to take a pointer to a status struct.
	(target_save_trace_data): New macro.
	(target_upload_tracepoints): New macro.
	(target_upload_trace_state_variables): New macro.
	(target_get_raw_trace_data): New macro.
	* target.c (update_current_target): Add new methods, change
	signature of to_get_trace_status.
	* remote.c (hex2bin): Make globally visible.
	(bin2hex): Ditto.
	(remote_download_trace_state_variable): Download name also.
	(remote_get_trace_status): Update parameter, use
	parse_trace_status.
	(remote_save_trace_data): New function.
	(remote_upload_tracepoints): New function.
	(remote_upload_trace_state_variables): New function.
	(remote_get_raw_trace_data): New function.
	(remote_start_remote): Use them.
	(_initialize_remote_ops): Add operations.
	* ax-gdb.c: Include breakpoint.h.
	* breakpoint.c (create_tracepoint_from_upload): Use
	break_command_really, return tracepoint, warn about unimplemented
	parts.
	* NEWS: Mention trace file addition.

	* gdb.texinfo (Trace Files): New section.
	(Tracepoint Packets): Document QTSave and qTBuffer.
	(Trace File Format): New appendix.

	* generic/gdbtk-bp.c (gdb_trace_status): Use current_trace_status.

	* gdb.trace/tfile.c: New file.
	* gdb.trace/tfile.exp: New file.