libjava/include/mips-signal.h

   1 // mips-signal.h - Catch runtime signals and turn them into exceptions
   2 // on an mips based Linux system.
   3
   4 /* Copyright (C) 1998, 1999, 2001, 2002, 2003  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 /* Adapted from sparc-signal.h and powerpc-signal.h
  13    by David Daney <ddaney@avtrex.com> */
  14
  15 #ifndef JAVA_SIGNAL_H
  16 #define JAVA_SIGNAL_H 1
  17
  18 #include <signal.h>
  19 #include <unistd.h>
  20 #include <sys/syscall.h>
  21 /* #include <asm/ucontext.h> structures we use are here but clash with
  22    sys/ucontext.h included by java-signal.h from prims.cc */
  23
  24 #define HANDLE_SEGV 1
  25 #undef HANDLE_FPE
  26
  27 /* The third parameter to the signal handler points to something with
  28  * this structure defined in asm/ucontext.h, but the name clashes with
  29  * struct ucontext from sys/ucontext.h so this private copy is used. */
  30 typedef struct _sig_ucontext {
  31     unsigned long         uc_flags;
  32     struct _sig_ucontext  *uc_link;
  33     stack_t               uc_stack;
  34     struct sigcontext uc_mcontext;
  35     sigset_t      uc_sigmask;
  36 } sig_ucontext_t;
  37
  38 /* We use kernel_sigaction here because we're calling the kernel
  39    directly rather than via glibc. The sigaction structure that the
  40    syscall uses is a different shape from the one in userland and not
  41    visible to us in a header file so we define it here.
  42    Additionally we want a proper prototype for the handler function
  43    with the struct sigcontext pointer passed by the kernel as the 2nd
  44    argument, which isn't there in userland headers. */
  45
  46 struct kernel_sigaction {
  47     unsigned int k_sa_flags;
  48     void       (*k_sa_handler) (int, siginfo_t *, sig_ucontext_t *);
  49     sigset_t     k_sa_mask;
  50     void       (*k_sa_restorer)(void);
  51     int          k_sa_resv[1];  /* reserved */
  52 };
  53
  54
  55
  56 #define SIGNAL_HANDLER(_name) \
  57 static void _name (int _dummy, siginfo_t *_info, sig_ucontext_t *_arg)
  58
  59 /*
  60  *  MIPS leaves pc pointing at the faulting instruction, but the
  61  *  unwinder expects it to point to the following instruction
  62  */
  63
  64 #define MAKE_THROW_FRAME(_exception) \
  65 do                                   \
  66 {                                    \
  67   _arg->uc_mcontext.sc_pc += 4;      \
  68   (void)_dummy;                      \
  69   (void)_info;                       \
  70 }                                    \
  71 while (0)
  72
  73 /* For an explanation why we cannot simply use sigaction to
  74    install the handlers, see i386-signal.h.  */
  75
  76 #define INIT_SEGV                                    \
  77 do                                                   \
  78   {                                                  \
  79     struct kernel_sigaction kact;                    \
  80     kact.k_sa_handler = catch_segv;                  \
  81     kact.k_sa_flags = SA_SIGINFO | SA_NODEFER;       \
  82     sigemptyset (&kact.k_sa_mask);                   \
  83     syscall (SYS_sigaction, SIGSEGV, &kact, NULL);   \
  84   }                                                  \
  85 while (0)
  86
  87
  88 #endif /* JAVA_SIGNAL_H */
  89