Implement the multiprocess extensions, and add linux multiprocess
support.
* server.h (ULONGEST): Declare.
(struct ptid, ptid_t): New.
(minus_one_ptid, null_ptid): Declare.
(ptid_build, pid_to_ptid, ptid_get_pid, ptid_get_lwp)
(ptid_get_tid, ptid_equal, ptid_is_pid): Declare.
(struct inferior_list_entry): Change `id' type from unsigned from
to ptid_t.
(struct sym_cache, struct breakpoint, struct
process_info_private): Forward declare.
(struct process_info): Declare.
(current_process): Declare.
(all_processes): Declare.
(initialize_inferiors): Declare.
(add_thread): Adjust to use ptid_t.
(thread_id_to_gdb_id, thread_to_gdb_id, gdb_id_to_thread_id): Ditto.
(add_process, remove_process, find_thread_pid): Declare.
(find_inferior_id): Adjust to use ptid_t.
(cont_thread, general_thread, step_thread): Change type to ptid_t.
(multi_process): Declare.
(push_event): Adjust to use ptid_t.
(read_ptid, write_ptid): Declare.
(prepare_resume_reply): Adjust to use ptid_t.
(clear_symbol_cache): Declare.
* inferiors.c (all_processes): New.
(null_ptid, minus_one_ptid): New.
(ptid_build, pid_to_ptid, ptid_get_pid, ptid_get_lwp)
(ptid_get_tid, ptid_equal, ptid_is_pid): New.
(add_thread): Change unsigned long to ptid. Remove gdb_id
parameter. Adjust.
(thread_id_to_gdb_id, thread_to_gdb_id): Change unsigned long to ptid.
(gdb_id_to_thread): Rename to ...
(find_thread_pid): ... this. Change unsigned long to ptid.
(gdb_id_to_thread_id, find_inferior_id): Change unsigned long to ptid.
(loaded_dll, pull_pid_from_list): Adjust.
(add_process, remove_process, find_process_pid)
(get_thread_process, current_process, initialize_inferiors): New.
* target.h (struct thread_resume) <thread>: Change type to ptid_t.
(struct target_waitstatus) <related_pid>: Ditto.
(struct target_ops) <kill, detach>: Add `pid' argument. Change
return type to int.
(struct target_ops) <join>: Add `pid' argument.
(struct target_ops) <thread_alive>: Change pid's type to ptid_t.
(struct target_ops) <wait>: Add `ptid' field. Change return type
to ptid.
(kill_inferior, detach_inferior, join_inferior): Add `pid' argument.
(mywait): Add `ptid' argument. Change return type to ptid_t.
(target_pid_to_str): Declare.
* target.c (set_desired_inferior): Adjust to use ptids.
(mywait): Add new `ptid' argument. Adjust.
(target_pid_to_str): New.
* mem-break.h (free_all_breakpoints): Declare.
* mem-break.c (breakpoints): Delelete.
(set_breakpoint_at, delete_breakpoint, find_breakpoint_at)
(check_mem_read, check_mem_write, delete_all_breakpoints): Adjust
to use per-process breakpoint list.
(free_all_breakpoints): New.
* remote-utils.c (struct sym_cache) <name>: Drop `const'.
(symbol_cache, all_symbols_looked_up): Delete.
(hexchars): New.
(ishex, unpack_varlen_hex, write_ptid, hex_or_minus_one,
read_ptid): New.
(prepare_resume_reply): Change ptid argument's type from unsigned
long to ptid_t. Adjust. Implement W;process and X;process.
(free_sym_cache, clear_symbol_cache): New.
(look_up_one_symbol): Adjust to per-process symbol cache. *
* server.c (cont_thread, general_thread, step_thread): Change type
to ptid_t.
(attached): Delete.
(multi_process): New.
(last_ptid): Change type to ptid_t.
(struct vstop_notif) <ptid>: Change type to ptid_t.
(queue_stop_reply, push_event): Change `ptid' argument's type to
ptid_t.
(discard_queued_stop_replies): Add `pid' argument.
(start_inferior): Adjust to use ptids. Adjust to mywait interface
changes. Don't reference the `attached' global.
(attach_inferior): Adjust to mywait interface changes.
(handle_query): Adjust to use ptids. Parse GDB's qSupported
features. Handle and report "multiprocess+". Handle
"qAttached:PID".
(handle_v_cont): Adjust to use ptids. Adjust to mywait interface
changes.
(handle_v_kill): New.
(handle_v_stopped): Adjust to use target_pid_to_str.
(handle_v_requests): Allow multiple attaches and runs when
multiprocess extensions are in effect. Handle "vKill".
(myresume): Adjust to use ptids.
(queue_stop_reply_callback): Add `arg' parameter. Handle it.
(handle_status): Adjust to discard_queued_stop_replies interface
change.
(first_thread_of, kill_inferior_callback)
(detach_or_kill_inferior_callback, join_inferiors_callback): New.
(main): Call initialize_inferiors. Adjust to use ptids, killing
and detaching from all inferiors. Handle multiprocess packet
variants.
* linux-low.h: Include gdb_proc_service.h.
(struct process_info_private): New.
(struct linux_target_ops) <pid_of>: Use ptid_get_pid.
<lwpid_of>: Use ptid_get_lwp.
(get_lwp_thread): Adjust.
(struct lwp_info): Add `dead' member.
(find_lwp_pid): Declare.
* linux-low.c (thread_db_active): Delete.
(new_inferior): Adjust comment.
(inferior_pid): Delete.
(linux_add_process): New.
(handle_extended_wait): Adjust.
(add_lwp): Change unsigned long to ptid.
(linux_create_inferior): Add process to processes table. Adjust
to use ptids. Don't set new_inferior here.
(linux_attach_lwp): Rename to ...
(linux_attach_lwp_1): ... this. Add `initial' argument. Handle
it. Adjust to use ptids.
(linux_attach_lwp): New.
(linux_attach): Add process to processes table. Don't set
new_inferior here.
(struct counter): New.
(second_thread_of_pid_p, last_thread_of_process_p): New.
(linux_kill_one_lwp): Add `args' parameter. Handle it. Adjust to
multiple processes.
(linux_kill): Add `pid' argument. Handle it. Adjust to multiple
processes. Remove process from process table.
(linux_detach_one_lwp): Add `args' parameter. Handle it. Adjust
to multiple processes.
(any_thread_of): New.
(linux_detach): Add `pid' argument, and handle it. Remove process
from processes table.
(linux_join): Add `pid' argument. Handle it.
(linux_thread_alive): Change unsighed long argument to ptid_t.
Consider dead lwps as not being alive.
(status_pending_p): Rename `dummy' argument to `arg'. Filter out
threads we're not interested in.
(same_lwp, find_lwp_pid): New.
(linux_wait_for_lwp): Change `pid' argument's type from int to
ptid_t. Adjust.
(linux_wait_for_event): Rename to ...
(linux_wait_for_event_1): ... this. Change `pid' argument's type
from int to ptid_t. Adjust.
(linux_wait_for_event): New.
(linux_wait_1): Add `ptid' argument. Change return type to
ptid_t. Adjust. Use last_thread_of_process_p. Remove processes
that exit from the process table.
(linux_wait): Add `ptid' argument. Change return type to ptid_t.
Adjust.
(mark_lwp_dead): New.
(wait_for_sigstop): Adjust to use ptids. If a process exits while
stopping all threads, mark its main lwp as dead.
(linux_set_resume_request, linux_resume_one_thread): Adjust to use
ptids.
(fetch_register, usr_store_inferior_registers)
(regsets_fetch_inferior_registers)
(regsets_store_inferior_registers, linux_read_memory)
(linux_write_memory): Inline `inferior_pid'.
(linux_look_up_symbols): Adjust to use per-process
`thread_db_active'.
(linux_request_interrupt): Adjust to use ptids.
(linux_read_auxv): Inline `inferior_pid'.
(initialize_low): Don't reference thread_db_active.
* gdb_proc_service.h (struct ps_prochandle) <pid>: Remove.
* proc-service.c (ps_lgetregs): Use find_lwp_pid.
(ps_getpid): Return the pid of the current inferior.
* thread-db.c (proc_handle, thread_agent): Delete.
(thread_db_create_event, thread_db_enable_reporting): Adjust to
per-process data.
(find_one_thread): Change argument type to ptid_t. Adjust to
per-process data.
(maybe_attach_thread): Adjust to per-process data and ptids.
(thread_db_find_new_threads): Ditto.
(thread_db_init): Ditto.
* spu-low.c (spu_create_inferior, spu_attach): Add process to
processes table. Adjust to use ptids.
(spu_kill, spu_detach): Adjust interface. Remove process from
processes table.
(spu_join, spu_thread_alive): Adjust interface.
(spu_wait): Adjust interface. Remove process from processes
table. Adjust to use ptids.
* win32-low.c (current_inferior_tid): Delete.
(current_inferior_ptid): New.
(debug_event_ptid): New.
(thread_rec): Take a ptid. Adjust.
(child_add_thread): Add `pid' argument. Adjust to use ptids.
(child_delete_thread): Ditto.
(do_initial_child_stuff): Add `attached' argument. Add process to
processes table.
(child_fetch_inferior_registers, child_store_inferior_registers):
Adjust.
(win32_create_inferior): Pass 0 to do_initial_child_stuff.
(win32_attach): Pass 1 to do_initial_child_stuff.
(win32_kill): Adjust interface. Remove process from processes
table.
(win32_detach): Ditto.
(win32_join): Adjust interface.
(win32_thread_alive): Take a ptid.
(win32_resume): Adjust to use ptids.
(get_child_debug_event): Ditto.
(win32_wait): Adjust interface. Remove exiting process from
processes table.
* server.h (non_stop): Declare.
(gdb_client_data, handler_func): Declare.
(delete_file_handler, add_file_handler, start_event_loop):
Declare.
(handle_serial_event, handle_target_event, push_event)
(putpkt_notif): Declare.
* target.h (enum resume_kind): New.
(struct thread_resume): Replace `step' field by `kind' field.
(TARGET_WNOHANG): Define.
(struct target_ops) <wait>: Add `options' argument.
<supports_non_stop, async, start_non_stop>: New fields.
(target_supports_non_stop, target_async): New.
(start_non_stop): Declare.
(mywait): Add `options' argument.
* target.c (mywait): Add `options' argument. Print child exit
notifications here.
(start_non_stop): New.
* server.c (non_stop, own_buf, mem_buf): New globals.
(struct vstop_notif): New.
(notif_queue): New global.
(queue_stop_reply, push_event, discard_queued_stop_replies)
(send_next_stop_reply): New.
(start_inferior): Adjust to use resume_kind. Adjust to mywait
interface changes.
(attach_inferior): In non-stop mode, don't wait for the target
here.
(handle_general_set): Handle QNonStop.
(handle_query): When handling qC, return the current general
thread, instead of the first thread of the list.
(handle_query): If the backend supports non-stop mode, include
QNonStop+ in the qSupported query response.
(handle_v_cont): Adjust to use resume_kind. Handle resume_stop
and non-stop mode.
(handle_v_attach, handle_v_run): Handle non-stop mode.
(handle_v_stopped): New.
(handle_v_requests): Report support for vCont;t. Handle vStopped.
(myresume): Adjust to use resume_kind. Handle non-stop.
(queue_stop_reply_callback): New.
(handle_status): Handle non-stop mode.
(main): Clear non_stop flag on reconnection. Use the event-loop.
Refactor serial protocol handling from here ...
(process_serial_event): ... to this new function. When GDB
selects any thread, select one here. In non-stop mode, wait until
GDB acks all pending events before exiting.
(handle_serial_event, handle_target_event): New.
* remote-utils.c (remote_open): Install remote_desc in the event
loop.
(remote_close): Remove remote_desc from the event loop.
(putpkt_binary): Rename to...
(putpkt_binary_1): ... this. Add `is_notic' argument. Handle it.
(putpkt_binary): New as wrapper around putpkt_binary_1.
(putpkt_notif): New.
(prepare_resume_reply): In non-stop mode, don't change the
general_thread.
* event-loop.c: New.
* Makefile.in (OBJ): Add event-loop.o.
(event-loop.o): New rule.
* linux-low.h (pid_of): Moved here.
(lwpid_of): New.
(get_lwp_thread): Use lwpid_of.
(struct lwp_info): Delete `lwpid' field. Add `suspended' field.
* linux-low.c (pid_of): Delete.
(inferior_pid): Use lwpid_of.
(linux_event_pipe): New.
(target_is_async_p): New.
(delete_lwp): New.
(handle_extended_wait): Use lwpid_of.
(add_lwp): Don't set lwpid field.
(linux_attach_lwp): Adjust debug output. Use lwpid_of.
(linux_kill_one_lwp): If killing a running lwp, stop it first.
Use lwpid_of. Adjust to linux_wait_for_event interface changes.
(linux_detach_one_lwp): If detaching from a running lwp, stop it
first. Adjust to linux_wait_for_event interface changes. Use
lwpid_of.
(linux_detach): Don't delete the main lwp here.
(linux_join): Use my_waitpid. Avoid signal_pid. Use lwpid_of.
(status_pending_p): Don't consider explicitly suspended lwps.
(linux_wait_for_lwp): Take an integer pid instead of a lwp_info
pointer. Add OPTIONS argument. Change return type to int. Use
my_waitpid instead of sleeping. Handle WNOHANG. Use lwpid_of.
(linux_wait_for_event): Take an integer pid instead of a lwp_info
pointer. Add status pointer argument. Return a pid instead of a
status. Use lwpid_of. Adjust to linux_wait_for_lwp interface
changes. In non-stop mode, don't switch to a random thread.
(linux_wait): Rename to...
(linux_wait_1): ... this. Add target_options argument, and handle
it. Adjust to use resume_kind. Use lwpid_of. In non-stop mode,
don't handle the continue thread. Handle TARGET_WNOHANG. Merge
clean exit and signal exit code. Don't stop all threads in
non-stop mode. In all-stop mode, only stop all threads when
reporting a stop to GDB. Handle explicit thread stop requests.
(async_file_flush, async_file_mark): New.
(linux_wait): New.
(send_sigstop): Use lwpid_of.
(wait_for_sigstop): Use lwpid_of. Adjust to linux_wait_for_event
interface changes. In non-stop mode, don't switch to a random
thread.
(linux_resume_one_lwp): Use lwpid_of.
(linux_continue_one_thread, linux_queue_one_thread): Merge into ...
(linux_resume_one_thread): ... this. Handle resume_stop. In
non-stop mode, don't look for pending flag in all threads.
(resume_status_pending_p): Don't consider explicitly suspended
threads.
(my_waitpid): Reimplement. Emulate __WALL.
(linux_request_interrupt, linux_read_offsets, linux_xfer_siginfo):
Use lwpid_of.
(sigchld_handler, linux_supports_non_stop, linux_async)
(linux_start_non_stop): New.
(linux_target_ops): Register linux_supports_non_stop, linux_async
and linux_start_non_stop.
(initialize_low): Install SIGCHLD handler.
* thread-db.c (thread_db_create_event, find_one_thread)
(thread_db_get_tls_address): Use lwpid_of.
* win32-low.c (win32_detach): Adjust to use resume_kind.
(win32_wait): Add `options' argument.
* spu-low.c (spu_resume): Adjust to use resume_kind.
(spu_wait): Add `options' argument.
* target.h (enum target_waitkind): New.
(struct target_waitstatus): New.
(struct target_ops) <wait>: Return an unsigned long. Take a
target_waitstatus pointer instead of a char pointer.
(mywait): Likewise.
* target.c (mywait): Change prototype to return an unsigned long.
Take a target_waitstatus pointer instead of a char pointer. Adjust.
* server.h (thread_from_wait, old_thread_from_wait): Delete
declarations.
(prepare_resume_reply): Change prototype to take a
target_waitstatus.
* server.c (thread_from_wait, old_thread_from_wait): Delete.
(last_status, last_ptid): New.
(start_inferior): Remove "statusptr" argument. Adjust. Return a
pid instead of a signal.
(attach_inferior): Remove "status" and "signal" parameters.
Adjust.
(handle_query): For qGetTLSAddr, parse the thread id with strtol,
not as an address.
(handle_v_cont, handle_v_attach, handle_v_run, handle_v_kill)
(handle_v_requests, myresume): Remove "status" and "signal"
parameters. Adjust.
(handle_status): New.
(main): Delete local `status'. Adjust.
* remote-utils.c: Include target.h.
(prepare_resume_reply): Change prototype to take a
target_waitstatus. Adjust.
* linux-low.c (linux_wait): Adjust to new target_ops->wait
interface.
* spu-low.c (spu_wait): Adjust.
* win32-low.c (enum target_waitkind, struct target_waitstatus):
Delete.
(win32_wait): Adjust.
(struct target_ops): Add a `n' argument to the `resume' callback.
* server.c (start_inferior): Adjust.
(handle_v_cont, myresume): Adjust.
* linux-low.c (check_removed_breakpoint): Adjust to resume
interface change, and to removed leave_stopped field.
(resume_ptr): Delete.
(struct thread_resume_array): New.
(linux_set_resume_request): Add new `arg' parameter. Adjust to
resume interface change.
(linux_continue_one_thread, linux_queue_one_thread)
(resume_status_pending_p): Check if the resume field is NULL
instead of checking the leave_stopped member.
(linux_resume): Adjust to the target resume interface change.
* spu-low.c (spu_resume): Adjust to the target resume interface
change.
* win32-low.c (win32_detach, win32_resume): Ditto.
* linux-low.c (linux_wait_for_event): Don't clear the `stepping'
flag.
(wait_for_sigstop): Don't leave a finished single-step SIGTRAP
pending.
(linux_continue_one_thread): Only preserve the stepping flag if
there's a pending breakpoint.
gdb/testsuite/
* gdb.threads/pending-step.c, gdb.threads/pending-step.exp: New.
* linux-low.c (disabled_regsets, num_regsets): New.
(use_regsets_p): Delete.
(linux_wait_for_process): Clear disabled_regsets.
(regsets_fetch_inferior_registers): Check and set it.
(regsets_store_inferior_registers): Likewise.
(linux_fetch_registers, linux_store_registers): Do not use
use_regsets_p.
(initialize_low): Allocate disabled_regsets.
reg-s390.o and reg-s390x.o.
* linux-low.c (new_inferior): New global variable.
(linux_create_inferior, linux_attach): Set it.
(linux_wait_for_process): Call the_low_target.arch_setup after the
target has stopped for the first time.
(initialize_low): Do not call the_low_target.arch_setup.
* linux-s390-low.c (s390_get_pc): Support bi-arch operation.
(s390_set_pc): Likewise.
(s390_arch_setup): New function.
(the_low_target): Use s390_arch_setup as arch_setup routine.
* regcache.c (realloc_register_cache): New function.
(set_register_cache): Call it for each existing regcache.
(linux_kill, linux_detach): Clean up the process list.
* remote-utils.c (remote_open): Improve port number parsing.
(putpkt_binary, input_interrupt): Only send interrupts if the target
is running.
* server.c (extended_protocol): Make static.
(attached): Define earlier.
(exit_requested, response_needed, program_argv): New variables.
(target_running): New.
(start_inferior): Clear attached here.
(attach_inferior): Set attached here.
(require_running): Define.
(handle_query): Use require_running and target_running. Implement
"monitor exit".
(handle_v_attach, handle_v_run): New.
(handle_v_requests): Use require_running. Handle vAttach and vRun.
(gdbserver_usage): Update.
(main): Redo argument parsing. Handle --debug and --multi. Handle
--attach along with other options or after the port. Save
program_argv. Support no initial program. Resynchronize
communication with GDB after an error. Handle "monitor exit".
Use require_running and target_running. Always allow the extended
protocol. Do not error out for Hc0 or Hc-1. Do not automatically
restart in extended mode.
* README: Refer to the GDB manual. Update --attach usage.
* remote.c (struct remote_state): Add cached_wait_status.
(remote_exec_file): New variable.
(PACKET_vAttach, PACKET_vRun): New constants.
(extended_remote_restart): Do not query for status.
(struct start_remote_args): New.
(remote_start_remote): Take it as a second argument. Check
whether the target is running. Issue an error for non-running
non-extended targets. Cache the wait status. Set inferior_ptid
here.
(remote_open_1): Prompt to disconnect non-running targets. Make
sure the target is marked running. Do not set inferior_ptid here.
Update call to remote_start_remote. Do not call remote_check_symbols
if the target is not running.
(remote_detach_1): Rename from remote_detach. Take an EXTENDED
argument. Handle a non-running target.
(remote_detach): Use it.
(extended_remote_detach): New.
(remote_disconnect): Fix typo. Use remoute_mourn_1.
(extended_remote_attach_1, extended_remote_attach)
(extended_async_remote_attach): New.
(remote_vcont_resume): Remove unused variable.
(remote_wait, remote_async_wait): Use any cached wait status.
(putpkt_binary, getpkt): Clear any cached wait status.
(extended_remoute_mourn_1): New.
(extended_remote_mourn): Use it.
(extended_async_remote_mourn, extended_remote_run): New.
(extended_remote_create_inferior_1): New.
(extended_remote_create_inferior): Use it.
(extended_remote_async_create_inferior): Likewise.
(remote_xfer_partial): Skip for non-executing targets.
(init_extended_remote_ops): Set to_detach and to_attach.
(init_extended_async_remote_ops): Likewise. Use
extended_async_remote_mourn.
(_initialize_remote): Register vAttach, vRun, and
set remote exec-file.
* NEWS: Mention vAttach, vRun, and gdbserver extended-remote support.
* gdb.server/ext-attach.c, gdb.server/ext-attach.exp,
gdb.server/ext-run.exp: New files.
* lib/gdbserver-support.exp (gdbserver_download): New.
(gdbserver_start): New. Update gdbserver expected
output.
(gdbserver_spawn): Use them.
(gdbserver_start_extended): New.
* gdb.texinfo (Using the `gdbserver' Program): Add security
warning. Rearrange into subsections and subsubsections. Document
--multi and --debug. Correct --with-sysroot typo. Update --attach
usage. Make load reference clearer. Document monitor exit.
(Remote Configuration): Document set remote exec-file, attach-packet,
and run-packet.
(Packets): Document vAttach and vRun.
reinsert auto-delete breakpoints.
* mem-break.c (struct breakpoint): Change return type of handler to
int.
(set_breakpoint_at): Update handler type.
(reinsert_breakpoint_handler): Return 1 instead of calling
delete_breakpoint.
(reinsert_breakpoint_by_bp): Check for the original breakpoint before
setting a new one.
(check_breakpoints): Delete auto-delete breakpoints and return 2.
* mem-break.h (set_breakpoint_at): Update handler type.
* thread-db.c (thread_db_create_event, thread_db_create_event): Update.
* win32-low.c (auto_delete_breakpoint): New.
(get_child_debug_event): Use it.
(add_pid_to_list, pull_pid_from_list): New.
* linux-low.c (PTRACE_SETOPTIONS, PTRACE_GETEVENTMSG)
(PTRACE_O_TRACESYSGOOD, PTRACE_O_TRACEFORK, PTRACE_O_TRACEVFORK)
(PTRACE_O_TRACECLONE, PTRACE_O_TRACEEXEC, PTRACE_O_TRACEVFORKDONE)
(PTRACE_O_TRACEEXIT, PTRACE_EVENT_FORK, PTRACE_EVENT_VFORK)
(PTRACE_EVENT_CLONE, PTRACE_EVENT_EXEC, PTRACE_EVENT_VFORK_DONE)
(PTRACE_EVENT_EXIT, __WALL): Provide default definitions.
(stopped_pids, thread_db_active, must_set_ptrace_flags): New variables.
(using_threads): Always set to 1.
(handle_extended_wait): New.
(add_process): Do not set TID.
(linux_create_inferior): Set must_set_ptrace_flags.
(linux_attach_lwp): Remove TID argument. Do not check using_threads.
Use PTRACE_SETOPTIONS. Call new_thread_notify. Update all callers.
(linux_thread_alive): Rename TID argument to LWPID.
(linux_wait_for_process): Handle unknown processes. Do not use TID.
(linux_wait_for_event): Do not use TID or check using_threads. Update
call to dead_thread_notify. Call handle_extended_wait.
(linux_create_inferior): Use PTRACE_SETOPTIONS.
(send_sigstop): Delete sigstop_sent.
(wait_for_sigstop): Avoid TID.
(linux_supports_tracefork_flag, linux_tracefork_child, my_waitpid)
(linux_test_for_tracefork): New.
(linux_lookup_signals): Use thread_db_active and
linux_supports_tracefork_flag.
(initialize_low): Use thread_db_active and linux_test_for_tracefork.
* linux-low.h (get_process_thread): Avoid TID.
(struct process_ifo): Move thread_known and tid to the end. Remove
sigstop_sent.
(linux_attach_lwp, thread_db_init): Update prototypes.
* server.h (change_inferior_id): Delete prototype.
(add_pid_to_list, pull_pid_from_list): New prototypes.
* thread-db.c (thread_db_use_events): New.
(find_first_thread): Rename to...
(find_one_thread): ...this. Update callers and messages. Do not
call fatal. Check thread_db_use_events. Do not call
change_inferior_id or new_thread_notify.
(maybe_attach_thread): Update. Do not call new_thread_notify.
(thread_db_init): Set thread_db_use_events. Check use_events.
* utils.c (fatal, warning): Correct message prefix.
