libjava/include/x86_64-signal.h

   1 // x86_64-signal.h - Catch runtime signals and turn them into exceptions
   2 // on an x86_64 based GNU/Linux system.
   3
   4 /* Copyright (C) 2003, 2006  Free Software Foundation
   5
   6    This file is part of libgcj.
   7
   8 This software is copyrighted work licensed under the terms of the
   9 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
  10 details.  */
  11
  12
  13 #ifdef __x86_64__
  14
  15 #ifndef JAVA_SIGNAL_H
  16 #define JAVA_SIGNAL_H 1
  17
  18 #include <signal.h>
  19 #include <sys/syscall.h>
  20
  21 #define HANDLE_SEGV 1
  22
  23 #define SIGNAL_HANDLER(_name)   \
  24 static void _Jv_##_name (int, siginfo_t *, void *_p)
  25
  26 extern "C"
  27 {
  28   struct kernel_sigaction
  29   {
  30     void (*k_sa_sigaction)(int,siginfo_t *,void *);
  31     unsigned long k_sa_flags;
  32     void (*k_sa_restorer) (void);
  33     sigset_t k_sa_mask;
  34   };
  35 }
  36
  37 #define MAKE_THROW_FRAME(_exception)
  38
  39 #define RESTORE(name, syscall) RESTORE2 (name, syscall)
  40 #define RESTORE2(name, syscall)                 \
  41 asm                                             \
  42   (                                             \
  43    ".text\n"                                    \
  44    ".byte 0  # Yes, this really is necessary\n" \
  45    ".align 16\n"                                \
  46    "__" #name ":\n"                             \
  47    "    movq $" #syscall ", %rax\n"             \
  48    "    syscall\n"                              \
  49    );
  50
  51 /* The return code for realtime-signals.  */
  52 RESTORE (restore_rt, __NR_rt_sigreturn)
  53 void restore_rt (void) asm ("__restore_rt")
  54   __attribute__ ((visibility ("hidden")));
  55
  56 #define INIT_SEGV                                               \
  57 do                                                              \
  58   {                                                             \
  59     struct kernel_sigaction act;                                \
  60     act.k_sa_sigaction = _Jv_catch_segv;                        \
  61     sigemptyset (&act.k_sa_mask);                               \
  62     act.k_sa_flags = SA_SIGINFO|0x4000000;                      \
  63     act.k_sa_restorer = restore_rt;                             \
  64     syscall (SYS_rt_sigaction, SIGSEGV, &act, NULL, _NSIG / 8); \
  65   }                                                             \
  66 while (0)
  67
  68 /* We use syscall(SYS_rt_sigaction) in INIT_SEGV instead of
  69  * sigaction() because on some systems the pthreads wrappers for
  70  * signal handlers are not compiled with unwind information, so it's
  71  * not possible to unwind through them.  This is a problem that will
  72  * go away if all systems ever have pthreads libraries that are
  73  * compiled with unwind info.  */
  74
  75 #endif /* JAVA_SIGNAL_H */
  76
  77 #else /* __x86_64__ */
  78
  79 /* This is for the 32-bit subsystem on x86-64.  */
  80
  81 #define sigcontext_struct sigcontext
  82 #include <java-signal-aux.h>
  83
  84 #endif /* __x86_64__ */