Linux Sandbox: add RawSandboxDie()

sandbox/linux/seccomp-bpf/trap.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SANDBOX_LINUX_SECCOMP_BPF_TRAP_H__
 #define SANDBOX_LINUX_SECCOMP_BPF_TRAP_H__
 
 #include <signal.h>
 #include <stdint.h>
 
@@ skipping 72 matching lines @@
   // We only have a very small number of methods. We opt to make them static
   // and have them internally call GetInstance(). This is a little more
   // convenient than having each caller obtain short-lived reference to the
   // singleton.
   // It also gracefully deals with methods that should check for the singleton,
   // but avoid instantiating it, if it doesn't exist yet
   // (e.g. ErrorCodeFromTrapId()).
   static Trap *GetInstance();
   static void SigSysAction(int nr, siginfo_t *info, void *void_context);
 
-  void SigSys(int nr, siginfo_t *info, void *void_context);
+  // Make sure that SigSys is not inlined in order to get slightly better crash
+  // dumps.
+  void SigSys(int nr, siginfo_t *info, void *void_context)
+      __attribute__ ((noinline));
   ErrorCode MakeTrapImpl(TrapFnc fnc, const void *aux, bool safe);
   bool SandboxDebuggingAllowedByUser() const;
 
 
 
   // We have a global singleton that handles all of our SIGSYS traps. This
   // variable must never be deallocated after it has been set up initially, as
   // there is no way to reset in-kernel BPF filters that generate SIGSYS
   // events.
   static Trap *global_trap_;
 
   TrapIds   trap_ids_;             // Maps from TrapKeys to numeric ids
   ErrorCode *trap_array_;          // Array of ErrorCodes indexed by ids
   size_t    trap_array_size_;      // Currently used size of array
   size_t    trap_array_capacity_;  // Currently allocated capacity of array
   bool      has_unsafe_traps_;     // Whether unsafe traps have been enabled
 
   // Our constructor is private. A shared global instance is created
   // automatically as needed.
   // Copying and assigning is unimplemented. It doesn't make sense for a
   // singleton.
   DISALLOW_IMPLICIT_CONSTRUCTORS(Trap);
 };
 
 }  // namespace playground2
 
 #endif  // SANDBOX_LINUX_SECCOMP_BPF_TRAP_H__