src/runtime/interrupt.h

   1 /*
   2  * This software is part of the SBCL system. See the README file for
   3  * more information.
   4  *
   5  * This software is derived from the CMU CL system, which was
   6  * written at Carnegie Mellon University and released into the
   7  * public domain. The software is in the public domain and is
   8  * provided with absolutely no warranty. See the COPYING and CREDITS
   9  * files for more information.
  10  */
  11
  12 #if !defined(_INCLUDE_INTERRUPT_H_)
  13 #define _INCLUDE_INTERRUPT_H_
  14
  15 #include "runtime.h"
  16 #include <string.h>
  17
  18 extern void get_current_sigmask(sigset_t *sigset);
  19
  20 /* Set all deferrable signals into *s. */
  21 extern void sigaddset_deferrable(sigset_t *s);
  22 /* Set all blockable signals into *s. */
  23 extern void sigaddset_blockable(sigset_t *s);
  24 /* Set all gc signals into *s. */
  25 extern void sigaddset_gc(sigset_t *s);
  26
  27 extern sigset_t deferrable_sigset;
  28 extern sigset_t blockable_sigset;
  29 extern sigset_t gc_sigset;
  30
  31 extern boolean deferrables_blocked_p(sigset_t *sigset);
  32 extern boolean blockables_blocked_p(sigset_t *sigset);
  33 extern boolean gc_signals_blocked_p(sigset_t *sigset);
  34
  35 extern void check_deferrables_blocked_or_lose(sigset_t *sigset);
  36 extern void check_blockables_blocked_or_lose(sigset_t *sigset);
  37 extern void check_gc_signals_blocked_or_lose(sigset_t *sigset);
  38
  39 extern void check_deferrables_unblocked_or_lose(sigset_t *sigset);
  40 extern void check_blockables_unblocked_or_lose(sigset_t *sigset);
  41 extern void check_gc_signals_unblocked_or_lose(sigset_t *sigset);
  42
  43 extern void block_deferrable_signals(sigset_t *old);
  44 extern void block_blockable_signals(sigset_t *old);
  45
  46 extern void unblock_deferrable_signals(sigset_t *where, sigset_t *old);
  47 extern void unblock_gc_signals(sigset_t *where, sigset_t *old);
  48
  49 extern void maybe_save_gc_mask_and_block_deferrables(sigset_t *sigset);
  50
  51 /* maximum signal nesting depth
  52  *
  53  * FIXME: In CMUCL this was 4096, and it was first scaled down to 256
  54  * and then 32, until finally Stumpwm broke: it is possible to receive
  55  * interrupts in sufficiently quick succession that handler nesting
  56  * can become preposterous. Scaling this back up to 1024 is a bandaid:
  57  * for a real fix we should consider the following things:
  58  *
  59  *   We should almost certainly always use
  60  *   arrange_return_to_lisp_function, though it needs to be thought
  61  *   about arguments, and it needs to be able to pass a frobbable
  62  *   context to the callee...
  63  *
  64  *   There are cases when nesting handlers is exactly what we want:
  65  *   eg. SIGINT.
  66  *
  67  *   There are cases when we probably want to drop duplicate signals
  68  *   on the floor if they arrive before the previous one has been handled.
  69  *   Eg. SIGPROF.
  70  *
  71  *   There are cases when we probably want to handle duplicate signals
  72  *   after the previous handler has returned, not before. Eg. SIGALARM.
  73  *
  74  * -- NS 2007-01-29
  75  */
  76 /* No longer defined here, but in 'compiler/generic/parms.lisp' due to
  77    requirement that Lisp skip this many words when assigning thread-local
  78    storage indices */
  79 // #define MAX_INTERRUPTS 1024
  80
  81 union interrupt_handler {
  82     lispobj lisp;
  83     void (*c)(int, siginfo_t*, os_context_t*);
  84 };
  85
  86 extern union interrupt_handler interrupt_handlers[NSIG];
  87
  88 struct interrupt_data {
  89     /* signal information for pending signal.  pending_signal=0 when there
  90      * is no pending signal. */
  91     void (*pending_handler) (int, siginfo_t*, os_context_t*) ;
  92     int pending_signal;
  93     siginfo_t pending_info;
  94     sigset_t pending_mask;
  95     /* Was pending mask saved for gc request? True if GC_PENDING or
  96      * SIG_STOP_FOR_GC happened in a pseudo atomic with GC_INHIBIT NIL
  97      * and with no pending handler. Both deferrable interrupt handlers
  98      * and gc are careful not to clobber each other's pending_mask. */
  99     boolean gc_blocked_deferrables;
 100 #ifdef GENCGC_IS_PRECISE
 101     /* On PPC when consing wants to turn to alloc(), it does so via a
 102      * trap. When alloc() wants to save the sigmask it consults
 103      * allocation_trap_context. It does not look up the most recent
 104      * context, because alloc() can be called from other places
 105      * too. */
 106     os_context_t *allocation_trap_context;
 107 #endif
 108 };
 109
 110 typedef lispobj (*call_into_lisp_lookalike)(
 111     lispobj fun, lispobj *args, int nargs);
 112
 113 extern boolean interrupt_handler_pending_p(void);
 114 extern void interrupt_init(void);
 115 extern void fake_foreign_function_call(os_context_t* context);
 116 extern void undo_fake_foreign_function_call(os_context_t* context);
 117 extern void arrange_return_to_c_function(
 118     os_context_t *, call_into_lisp_lookalike, lispobj);
 119 extern void arrange_return_to_lisp_function(os_context_t *, lispobj);
 120 extern void interrupt_handle_now(int, siginfo_t*, os_context_t*);
 121 extern void interrupt_handle_pending(os_context_t*);
 122 extern void interrupt_internal_error(os_context_t*, boolean continuable);
 123 extern boolean handle_guard_page_triggered(os_context_t *,os_vm_address_t);
 124 extern boolean maybe_defer_handler(void *handler, struct interrupt_data *data,
 125                                    int signal, siginfo_t *info,
 126                                    os_context_t *context);
 127 #if defined LISP_FEATURE_GENCGC
 128 /* assembly language stub that executes trap_PendingInterrupt */
 129 extern void do_pending_interrupt(void);
 130 #endif
 131
 132 #ifdef LISP_FEATURE_SB_THREAD
 133 extern void sig_stop_for_gc_handler(int, siginfo_t*, os_context_t*);
 134 #endif
 135 typedef void (*interrupt_handler_t)(int, siginfo_t *, os_context_t *);
 136 extern void undoably_install_low_level_interrupt_handler (
 137                         int signal,
 138                         interrupt_handler_t handler);
 139 extern uword_t install_handler(int signal,
 140                                interrupt_handler_t handler,
 141                                int synchronous);
 142
 143 /* The void* casting here avoids having to mess with the various types
 144  * of function argument lists possible for signal handlers:
 145  * SA_SIGACTION handlers have one signature, and the default old-style
 146  * signal(..) handlers have another, and attempting to represent them
 147  * "cleanly" with union types is in fact a mess. */
 148 #define ARE_SAME_HANDLER(x, y) ((void*)(x) == (void*)(y))
 149
 150 extern void handle_trap(os_context_t *context, int trap);
 151
 152 #ifndef LISP_FEATURE_WIN32
 153 extern void lisp_memory_fault_error(os_context_t *context,
 154                                     os_vm_address_t addr);
 155 #endif
 156
 157 #include "thread.h"
 158
 159 extern void lower_thread_control_stack_guard_page(struct thread *th);
 160 extern void reset_thread_control_stack_guard_page(struct thread *th);
 161
 162 #if defined(LISP_FEATURE_SB_SAFEPOINT) && !defined(LISP_FEATURE_WIN32)
 163 # ifdef LISP_FEATURE_SB_THRUPTION
 164 void thruption_handler(int signal, siginfo_t *info, os_context_t *context);
 165 # endif
 166 #endif
 167
 168 #endif