diff options
Diffstat (limited to 'libjava/include/i386-signal.h')
| -rw-r--r-- | libjava/include/i386-signal.h | 67 |
1 files changed, 41 insertions, 26 deletions
diff --git a/libjava/include/i386-signal.h b/libjava/include/i386-signal.h index 737b3689d97..6ad496c47a4 100644 --- a/libjava/include/i386-signal.h +++ b/libjava/include/i386-signal.h @@ -1,6 +1,7 @@ -// i386-signal.h - Catch runtime signals and turn them into exceptions. +// i386-signal.h - Catch runtime signals and turn them into exceptions +// on an i386 based Linux system. -/* Copyright (C) 1998, 1999, 2001 Free Software Foundation +/* Copyright (C) 1998, 1999, 2001, 2002 Free Software Foundation This file is part of libgcj. @@ -8,10 +9,6 @@ This software is copyrighted work licensed under the terms of the Libgcj License. Please consult the file "LIBGCJ_LICENSE" for details. */ -/* This technique should work for all i386 based Unices which conform - * to iBCS2. This includes all versions of Linux more recent than 1.3 - */ - #ifndef JAVA_SIGNAL_H #define JAVA_SIGNAL_H 1 @@ -99,28 +96,40 @@ do \ } \ while (0) -#define INIT_SEGV \ -do \ - { \ - nullp = new java::lang::NullPointerException (); \ - struct sigaction act; \ - act.sa_handler = catch_segv; \ - sigemptyset (&act.sa_mask); \ - act.sa_flags = 0; \ - syscall (SYS_sigaction, SIGSEGV, &act, NULL); \ - } \ +/* We use old_kernel_sigaction here because we're calling the kernel + directly rather than via glibc. The sigaction structure that the + syscall uses is a different shape from the one in userland and not + visible to us in a header file so we define it here. */ + +struct old_i386_kernel_sigaction { + void (*k_sa_handler) (int); + unsigned long k_sa_mask; + unsigned long k_sa_flags; + void (*sa_restorer) (void); +}; + +#define INIT_SEGV \ +do \ + { \ + nullp = new java::lang::NullPointerException (); \ + struct old_i386_kernel_sigaction kact; \ + kact.k_sa_handler = catch_segv; \ + kact.k_sa_mask = 0; \ + kact.k_sa_flags = 0; \ + syscall (SYS_sigaction, SIGSEGV, &kact, NULL); \ + } \ while (0) #define INIT_FPE \ do \ - { \ - arithexception = new java::lang::ArithmeticException \ + { \ + arithexception = new java::lang::ArithmeticException \ (JvNewStringLatin1 ("/ by zero")); \ - struct sigaction act; \ - act.sa_handler = catch_fpe; \ - sigemptyset (&act.sa_mask); \ - act.sa_flags = 0; \ - syscall (SYS_sigaction, SIGFPE, &act, NULL); \ + struct old_i386_kernel_sigaction kact; \ + kact.k_sa_handler = catch_fpe; \ + kact.k_sa_mask = 0; \ + kact.k_sa_flags = 0; \ + syscall (SYS_sigaction, SIGFPE, &kact, NULL); \ } \ while (0) @@ -133,9 +142,15 @@ while (0) * when returning from a signal handler. If we return from our divide * handler to a linuxthreads wrapper, we will lose the PC adjustment * we made and return to the faulting instruction again. Using - * syscall(SYS_sigaction) causes our handler to be called directly by - * the kernel, bypassing any wrappers. This is a kludge, and a future - * version of this handler will do something better. */ + * syscall(SYS_sigaction) causes our handler to be called directly + * by the kernel, bypassing any wrappers. + + * Also, there is at the present time no unwind info in the + * linuxthreads library's signal handlers and so we can't unwind + * through them anyway. + + * Finally, the code that glibc uses to return from a signal handler + * is subject to change. */ #endif /* JAVA_SIGNAL_H */ |