kernel: +arch_get_thread_debug_cpu_state()

Similar to arch_get_debug_cpu_state(), but the thread whose CPU state
to retrieve is specified. Works only for threads that aren't running,
and on x86-64 we can get the FPU state only when the thread was
interrupted in userland.
Not implemented for the incomplete architecture ports.

headers/private/kernel/arch/user_debugger.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2005-2011, Ingo Weinhold, [email protected].
+ * Copyright 2005-2016, Ingo Weinhold, [email protected].
  * Distributed under the terms of the MIT License.
  */
 #ifndef KERNEL_ARCH_USER_DEBUGGER_H
@@ -19,6 +19,11 @@ extern "C" {
 struct arch_team_debug_info;
 struct arch_thread_debug_info;
 
+namespace BKernel {
+    struct Thread;
+}
+using BKernel::Thread;
+
 
 void arch_clear_team_debug_info(struct arch_team_debug_info *info);
 void arch_destroy_team_debug_info(struct arch_team_debug_info *info);
@@ -29,6 +34,8 @@ void arch_update_thread_single_step();
 
 void arch_set_debug_cpu_state(const debug_cpu_state *cpuState);
 void arch_get_debug_cpu_state(debug_cpu_state *cpuState);
+status_t arch_get_thread_debug_cpu_state(Thread *thread,
+	debug_cpu_state *cpuState);
 
 status_t arch_set_breakpoint(void *address);
 status_t arch_clear_breakpoint(void *address);