From 4210d83ee607bffaf27a235f0475bf1e5ea8266d Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Thu, 12 Dec 2013 11:12:30 -0500 Subject: [PATCH] Do the target-waiting within do_initial_child_stuff on Windows. This is a preparatory patch that achieves two goals: . Makes the initial event handling more similar to GDB's; . Opens the door for implementing post-inititial-handling operations. At the moment, this is only done on Windows, where the post-initial-handling is going to be needed (in the context of Windows 2012). And because we're close to creating the gdb 7.7 branch, making that change for all platforms is a little more risk that we'd like. So the change is currently implemented on Windows. gdb/gdbserver/ChangeLog: * target.c (mywait): Set OURSTATUS->KIND to TARGET_WAITKIND_STOPPED if equal to TARGET_WAITKIND_LOADED. * win32-low.c (cached_status): New static global. (win32_wait): Add declaration. (do_initial_child_stuff): Flush all initial pending debug events up to the initial breakpoint. (win32_wait): If CACHED_STATUS was set, return that instead of doing a real wait. Remove the code resuming the execution of the inferior after receiving a TARGET_WAITKIND_LOADED event during the initial phase. Also remove the code changing OURSTATUS->KIND from TARGET_WAITKIND_LOADED to TARGET_WAITKIND_STOPPED. --- gdb/gdbserver/ChangeLog | 15 ++++++++++++ gdb/gdbserver/target.c | 5 ++++ gdb/gdbserver/win32-low.c | 61 +++++++++++++++++++++++++++++++++++------------ 3 files changed, 66 insertions(+), 15 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 26d305e..9f8eb9e 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,18 @@ +2013-12-13 Pedro Alves + + * target.c (mywait): Set OURSTATUS->KIND to TARGET_WAITKIND_STOPPED + if equal to TARGET_WAITKIND_LOADED. + * win32-low.c (cached_status): New static global. + (win32_wait): Add declaration. + (do_initial_child_stuff): Flush all initial pending debug events + up to the initial breakpoint. + (win32_wait): If CACHED_STATUS was set, return that instead + of doing a real wait. Remove the code resuming the execution + of the inferior after receiving a TARGET_WAITKIND_LOADED event + during the initial phase. Also remove the code changing + OURSTATUS->KIND from TARGET_WAITKIND_LOADED to + TARGET_WAITKIND_STOPPED. + 2013-12-11 Yao Qi * notif.c (handle_notif_ack): Return 0 if no notification diff --git a/gdb/gdbserver/target.c b/gdb/gdbserver/target.c index d4a2a98..d229933 100644 --- a/gdb/gdbserver/target.c +++ b/gdb/gdbserver/target.c @@ -82,6 +82,11 @@ mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options, ret = (*the_target->wait) (ptid, ourstatus, options); + /* We don't expose _LOADED events to gdbserver core. See the + `dlls_changed' global. */ + if (ourstatus->kind == TARGET_WAITKIND_LOADED) + ourstatus->kind = TARGET_WAITKIND_STOPPED; + /* If GDB is connected through TCP/serial, then GDBserver will most probably be running on its own terminal/console, so it's nice to print there why is GDBserver exiting. If however, GDB is diff --git a/gdb/gdbserver/win32-low.c b/gdb/gdbserver/win32-low.c index 979eedd..a4c9e77 100644 --- a/gdb/gdbserver/win32-low.c +++ b/gdb/gdbserver/win32-low.c @@ -80,6 +80,11 @@ static enum gdb_signal last_sig = GDB_SIGNAL_0; /* The current debug event from WaitForDebugEvent. */ static DEBUG_EVENT current_event; +/* A status that hasn't been reported to the core yet, and so + win32_wait should return it next, instead of fetching the next + debug event off the win32 API. */ +static struct target_waitstatus cached_status; + /* Non zero if an interrupt request is to be satisfied by suspending all threads. */ static int soft_interrupt_requested = 0; @@ -97,6 +102,8 @@ typedef BOOL (WINAPI *winapi_DebugSetProcessKillOnExit) (BOOL KillOnExit); typedef BOOL (WINAPI *winapi_DebugBreakProcess) (HANDLE); typedef BOOL (WINAPI *winapi_GenerateConsoleCtrlEvent) (DWORD, DWORD); +static ptid_t win32_wait (ptid_t ptid, struct target_waitstatus *ourstatus, + int options); static void win32_resume (struct thread_resume *resume_info, size_t n); /* Get the thread ID from the current selected inferior (the current @@ -336,6 +343,34 @@ do_initial_child_stuff (HANDLE proch, DWORD pid, int attached) if (the_low_target.initial_stuff != NULL) (*the_low_target.initial_stuff) (); + + cached_status.kind = TARGET_WAITKIND_IGNORE; + + /* Flush all currently pending debug events (thread and dll list) up + to the initial breakpoint. */ + while (1) + { + struct target_waitstatus status; + + win32_wait (minus_one_ptid, &status, 0); + + /* Note win32_wait doesn't return thread events. */ + if (status.kind != TARGET_WAITKIND_LOADED) + { + cached_status = status; + break; + } + + { + struct thread_resume resume; + + resume.thread = minus_one_ptid; + resume.kind = resume_continue; + resume.sig = 0; + + win32_resume (&resume, 1); + } + } } /* Resume all artificially suspended threads if we are continuing @@ -1593,6 +1628,17 @@ win32_wait (ptid_t ptid, struct target_waitstatus *ourstatus, int options) { struct regcache *regcache; + if (cached_status.kind != TARGET_WAITKIND_IGNORE) + { + /* The core always does a wait after creating the inferior, and + do_initial_child_stuff already ran the inferior to the + initial breakpoint (or an exit, if creating the process + fails). Report it now. */ + *ourstatus = cached_status; + cached_status.kind = TARGET_WAITKIND_IGNORE; + return debug_event_ptid (¤t_event); + } + while (1) { if (!get_child_debug_event (ourstatus)) @@ -1612,21 +1658,6 @@ win32_wait (ptid_t ptid, struct target_waitstatus *ourstatus, int options) regcache = get_thread_regcache (current_inferior, 1); child_fetch_inferior_registers (regcache, -1); - - if (ourstatus->kind == TARGET_WAITKIND_LOADED - && !server_waiting) - { - /* When gdb connects, we want to be stopped at the - initial breakpoint, not in some dll load event. */ - child_continue (DBG_CONTINUE, -1); - break; - } - - /* We don't expose _LOADED events to gdbserver core. See - the `dlls_changed' global. */ - if (ourstatus->kind == TARGET_WAITKIND_LOADED) - ourstatus->kind = TARGET_WAITKIND_STOPPED; - return debug_event_ptid (¤t_event); default: OUTMSG (("Ignoring unknown internal event, %d\n", ourstatus->kind)); -- 2.7.4