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 *where, sigset_t *old);
  44 extern void block_blockable_signals(sigset_t *where, sigset_t *old);
  45 extern void block_gc_signals(sigset_t *where, sigset_t *old);
  46
  47 extern void unblock_deferrable_signals(sigset_t *where, sigset_t *old);
  48 extern void unblock_blockable_signals(sigset_t *where, sigset_t *old);
  49 extern void unblock_gc_signals(sigset_t *where, sigset_t *old);
  50
  51 extern void maybe_save_gc_mask_and_block_deferrables(sigset_t *sigset);
  52
  53 /* maximum signal nesting depth
  54  *
  55  * FIXME: In CMUCL this was 4096, and it was first scaled down to 256
  56  * and then 32, until finally Stumpwm broke: it is possible to receive
  57  * interrupts in sufficiently quick succession that handler nesting
  58  * can become preposterous. Scaling this back up to 1024 is a bandaid:
  59  * for a real fix we should consider the following things:
  60  *
  61  *   We should almost certainly always use
  62  *   arrange_return_to_lisp_function, though it needs to be thought
  63  *   about arguments, and it needs to be able to pass a frobbable
  64  *   context to the callee...
  65  *
  66  *   There are cases when nesting handlers is exactly what we want:
  67  *   eg. SIGINT.
  68  *
  69  *   There are cases when we probably want to drop duplicate signals
  70  *   on the floor if they arrive before the previous one has been handled.
  71  *   Eg. SIGPROF.
  72  *
  73  *   There are cases when we probably want to handle duplicate signals
  74  *   after the previous handler has returned, not before. Eg. SIGALARM.
  75  *
  76  * -- NS 2007-01-29
  77  */
  78 /* No longer defined here, but in 'compiler/generic/parms.lisp' due to
  79    requirement that Lisp skip this many words when assigning thread-local
  80    storage indices */
  81 // #define MAX_INTERRUPTS 1024
  82
  83 union interrupt_handler {
  84     lispobj lisp;
  85     void (*c)(int, siginfo_t*, os_context_t*);
  86 };
  87
  88 extern union interrupt_handler interrupt_handlers[NSIG];
  89
  90 struct interrupt_data {
  91     /* signal information for pending signal.  pending_signal=0 when there
  92      * is no pending signal. */
  93     void (*pending_handler) (int, siginfo_t*, os_context_t*) ;
  94     int pending_signal;
  95     siginfo_t pending_info;
  96     sigset_t pending_mask;
  97     /* Was pending mask saved for gc request? True if GC_PENDING or
  98      * SIG_STOP_FOR_GC happened in a pseudo atomic with GC_INHIBIT NIL
  99      * and with no pending handler. Both deferrable interrupt handlers
 100      * and gc are careful not to clobber each other's pending_mask. */
 101     boolean gc_blocked_deferrables;
 102 #ifdef GENCGC_IS_PRECISE
 103     /* On PPC when consing wants to turn to alloc(), it does so via a
 104      * trap. When alloc() wants to save the sigmask it consults
 105      * allocation_trap_context. It does not look up the most recent
 106      * context, because alloc() can be called from other places
 107      * too. */
 108     os_context_t *allocation_trap_context;
 109 #endif
 110 };
 111
 112 typedef lispobj (*call_into_lisp_lookalike)(
 113     lispobj fun, lispobj *args, int nargs);
 114
 115 extern boolean interrupt_handler_pending_p(void);
 116 extern void interrupt_init(void);
 117 extern void fake_foreign_function_call(os_context_t* context);
 118 extern void undo_fake_foreign_function_call(os_context_t* context);
 119 extern void arrange_return_to_c_function(
 120     os_context_t *, call_into_lisp_lookalike, lispobj);
 121 extern void arrange_return_to_lisp_function(os_context_t *, lispobj);
 122 extern void interrupt_handle_now(int, siginfo_t*, os_context_t*);
 123 extern void interrupt_handle_pending(os_context_t*);
 124 extern void interrupt_internal_error(os_context_t*, boolean continuable);
 125 extern boolean handle_guard_page_triggered(os_context_t *,os_vm_address_t);
 126 extern boolean maybe_defer_handler(void *handler, struct interrupt_data *data,
 127                                    int signal, siginfo_t *info,
 128                                    os_context_t *context);
 129 #if defined LISP_FEATURE_GENCGC
 130 /* assembly language stub that executes trap_PendingInterrupt */
 131 extern void do_pending_interrupt(void);
 132 #endif
 133
 134 #ifdef LISP_FEATURE_SB_THREAD
 135 extern void sig_stop_for_gc_handler(int, siginfo_t*, os_context_t*);
 136 #endif
 137 typedef void (*interrupt_handler_t)(int, siginfo_t *, os_context_t *);
 138 extern void undoably_install_low_level_interrupt_handler (
 139                         int signal,
 140                         interrupt_handler_t handler);
 141 extern uword_t install_handler(int signal,
 142                                interrupt_handler_t handler,
 143                                int synchronous);
 144
 145 /* The void* casting here avoids having to mess with the various types
 146  * of function argument lists possible for signal handlers:
 147  * SA_SIGACTION handlers have one signature, and the default old-style
 148  * signal(..) handlers have another, and attempting to represent them
 149  * "cleanly" with union types is in fact a mess. */
 150 #define ARE_SAME_HANDLER(x, y) ((void*)(x) == (void*)(y))
 151
 152 extern void handle_trap(os_context_t *context, int trap);
 153
 154 #ifndef LISP_FEATURE_WIN32
 155 extern void lisp_memory_fault_error(os_context_t *context,
 156                                     os_vm_address_t addr);
 157 #endif
 158
 159 #include "thread.h"
 160
 161 extern void lower_thread_control_stack_guard_page(struct thread *th);
 162 extern void reset_thread_control_stack_guard_page(struct thread *th);
 163
 164 #if defined(LISP_FEATURE_SB_SAFEPOINT) && !defined(LISP_FEATURE_WIN32)
 165 # ifdef LISP_FEATURE_SB_THRUPTION
 166 void thruption_handler(int signal, siginfo_t *info, os_context_t *context);
 167 # endif
 168 #endif
 169
 170 #endif