From 4d5d1aaa19eac2f7bbdace73e44d4057bcd7a9c4 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Mon, 3 Dec 2007 01:18:49 +0000 Subject: [PATCH] * win32-low.c (soft_interrupt_requested, faked_breakpoint): New global variables. (child_add_thread): Minor cleanup. (child_continue): Resume artificially suspended threads before calling ContinueDebugEvent. (suspend_one_thread): New. (fake_breakpoint_event): New. (get_child_debug_event): Change return type to int. Check here if gdb sent an interrupt request. If a soft interrupt was requested, fake a breakpoint event. Return 0 if there is no event to handle, and 1 otherwise. (win32_wait): Don't check here if gdb sent an interrupt request. Ensure there is a valid event to handle. (win32_request_interrupt): Add soft interruption method as last resort. --- gdb/gdbserver/ChangeLog | 19 ++++++++ gdb/gdbserver/win32-low.c | 98 +++++++++++++++++++++++++++++++-------- 2 files changed, 97 insertions(+), 20 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 86f4d72979..eb79471178 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,22 @@ +2007-12-03 Leo Zayas + Pedro Alves + + * win32-low.c (soft_interrupt_requested, faked_breakpoint): New + global variables. + (child_add_thread): Minor cleanup. + (child_continue): Resume artificially suspended threads before + calling ContinueDebugEvent. + (suspend_one_thread): New. + (fake_breakpoint_event): New. + (get_child_debug_event): Change return type to int. Check here if + gdb sent an interrupt request. If a soft interrupt was requested, + fake a breakpoint event. Return 0 if there is no event to handle, + and 1 otherwise. + (win32_wait): Don't check here if gdb sent an interrupt request. + Ensure there is a valid event to handle. + (win32_request_interrupt): Add soft interruption method as last + resort. + 2007-12-03 Leo Zayas Pedro Alves diff --git a/gdb/gdbserver/win32-low.c b/gdb/gdbserver/win32-low.c index cc959819c1..d125e9bdcc 100644 --- a/gdb/gdbserver/win32-low.c +++ b/gdb/gdbserver/win32-low.c @@ -72,6 +72,14 @@ static enum target_signal last_sig = TARGET_SIGNAL_0; /* The current debug event from WaitForDebugEvent. */ static DEBUG_EVENT current_event; +/* Non zero if an interrupt request is to be satisfied by suspending + all threads. */ +static int soft_interrupt_requested = 0; + +/* Non zero if the inferior is stopped in a simulated breakpoint done + by suspending all the threads. */ +static int faked_breakpoint = 0; + #define NUM_REGS (the_low_target.num_regs) typedef BOOL WINAPI (*winapi_DebugActiveProcessStop) (DWORD dwProcessId); @@ -134,8 +142,7 @@ child_add_thread (DWORD tid, HANDLE h) if ((th = thread_rec (tid, FALSE))) return th; - th = (win32_thread_info *) malloc (sizeof (*th)); - memset (th, 0, sizeof (*th)); + th = calloc (1, sizeof (*th)); th->tid = tid; th->h = h; @@ -293,14 +300,17 @@ continue_one_thread (struct inferior_list_entry *this_thread, void *id_ptr) static BOOL child_continue (DWORD continue_status, int thread_id) { - BOOL res; + /* The inferior will only continue after the ContinueDebugEvent + call. */ + find_inferior (&all_threads, continue_one_thread, &thread_id); + faked_breakpoint = 0; - res = ContinueDebugEvent (current_event.dwProcessId, - current_event.dwThreadId, continue_status); - if (res) - find_inferior (&all_threads, continue_one_thread, &thread_id); + if (!ContinueDebugEvent (current_event.dwProcessId, + current_event.dwThreadId, + continue_status)) + return FALSE; - return res; + return TRUE; } /* Fetch register(s) from the current thread context. */ @@ -1247,19 +1257,67 @@ handle_exception (struct target_waitstatus *ourstatus) last_sig = ourstatus->value.sig; } -/* Get the next event from the child. */ + static void -get_child_debug_event (struct target_waitstatus *ourstatus) +suspend_one_thread (struct inferior_list_entry *entry) +{ + struct thread_info *thread = (struct thread_info *) entry; + win32_thread_info *th = inferior_target_data (thread); + + if (!th->suspended) + { + if (SuspendThread (th->h) == (DWORD) -1) + { + DWORD err = GetLastError (); + OUTMSG (("warning: SuspendThread failed in suspend_one_thread, " + "(error %d): %s\n", (int) err, strwinerror (err))); + } + else + th->suspended = 1; + } +} + +static void +fake_breakpoint_event (void) { - BOOL debug_event; + OUTMSG2(("fake_breakpoint_event\n")); + faked_breakpoint = 1; + + memset (¤t_event, 0, sizeof (current_event)); + current_event.dwThreadId = main_thread_id; + current_event.dwDebugEventCode = EXCEPTION_DEBUG_EVENT; + current_event.u.Exception.ExceptionRecord.ExceptionCode + = EXCEPTION_BREAKPOINT; + + for_each_inferior (&all_threads, suspend_one_thread); +} + +/* Get the next event from the child. */ + +static int +get_child_debug_event (struct target_waitstatus *ourstatus) +{ last_sig = TARGET_SIGNAL_0; ourstatus->kind = TARGET_WAITKIND_SPURIOUS; - /* Keep the wait time low enough for confortable remote interruption, - but high enough so gdbserver doesn't become a bottleneck. */ - if (!(debug_event = WaitForDebugEvent (¤t_event, 250))) - return; + /* Check if GDB sent us an interrupt request. */ + check_remote_input_interrupt_request (); + + if (soft_interrupt_requested) + { + soft_interrupt_requested = 0; + fake_breakpoint_event (); + goto gotevent; + } + + /* Keep the wait time low enough for confortable remote + interruption, but high enough so gdbserver doesn't become a + bottleneck. */ + if (!WaitForDebugEvent (¤t_event, 250)) + return 0; + + gotevent: current_inferior = (struct thread_info *) find_inferior_id (&all_threads, @@ -1376,6 +1434,7 @@ get_child_debug_event (struct target_waitstatus *ourstatus) current_inferior = (struct thread_info *) find_inferior_id (&all_threads, current_event.dwThreadId); + return 1; } /* Wait for the inferior process to change state. @@ -1390,10 +1449,8 @@ win32_wait (char *status) while (1) { - /* Check if GDB sent us an interrupt request. */ - check_remote_input_interrupt_request (); - - get_child_debug_event (&our_status); + if (!get_child_debug_event (&our_status)) + continue; switch (our_status.kind) { @@ -1500,7 +1557,8 @@ win32_request_interrupt (void) && DebugBreakProcess (current_process_handle)) return; - OUTMSG (("Could not interrupt process.\n")); + /* Last resort, suspend all threads manually. */ + soft_interrupt_requested = 1; } static const char * -- 2.34.1