LXR qemu/linux-user/signal-common.h

   1/*
   2 *  Emulation of Linux signals
   3 *
   4 *  Copyright (c) 2003 Fabrice Bellard
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License as published by
   8 *  the Free Software Foundation; either version 2 of the License, or
   9 *  (at your option) any later version.
  10 *
  11 *  This program is distributed in the hope that it will be useful,
  12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *  GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20#ifndef SIGNAL_COMMON_H
  21#define SIGNAL_COMMON_H
  22
  23#include "special-errno.h"
  24
  25/* Fallback addresses into sigtramp page. */
  26extern abi_ulong default_sigreturn;
  27extern abi_ulong default_rt_sigreturn;
  28
  29void setup_sigtramp(abi_ulong tramp_page);
  30
  31int on_sig_stack(unsigned long sp);
  32int sas_ss_flags(unsigned long sp);
  33abi_ulong target_sigsp(abi_ulong sp, struct target_sigaction *ka);
  34void target_save_altstack(target_stack_t *uss, CPUArchState *env);
  35abi_long target_restore_altstack(target_stack_t *uss, CPUArchState *env);
  36
  37static inline void target_sigemptyset(target_sigset_t *set)
  38{
  39    memset(set, 0, sizeof(*set));
  40}
  41
  42void host_to_target_sigset_internal(target_sigset_t *d,
  43                                    const sigset_t *s);
  44void target_to_host_sigset_internal(sigset_t *d,
  45                                    const target_sigset_t *s);
  46void tswap_siginfo(target_siginfo_t *tinfo,
  47                   const target_siginfo_t *info);
  48void set_sigmask(const sigset_t *set);
  49void force_sig(int sig);
  50void force_sigsegv(int oldsig);
  51void force_sig_fault(int sig, int code, abi_ulong addr);
  52#if defined(TARGET_ARCH_HAS_SETUP_FRAME)
  53void setup_frame(int sig, struct target_sigaction *ka,
  54                 target_sigset_t *set, CPUArchState *env);
  55#endif
  56void setup_rt_frame(int sig, struct target_sigaction *ka,
  57                    target_siginfo_t *info,
  58                    target_sigset_t *set, CPUArchState *env);
  59
  60void process_pending_signals(CPUArchState *cpu_env);
  61void signal_init(void);
  62void queue_signal(CPUArchState *env, int sig, int si_type,
  63                  target_siginfo_t *info);
  64void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
  65void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
  66int target_to_host_signal(int sig);
  67int host_to_target_signal(int sig);
  68long do_sigreturn(CPUArchState *env);
  69long do_rt_sigreturn(CPUArchState *env);
  70abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr,
  71                        CPUArchState *env);
  72int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
  73abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx,
  74                        abi_ulong unew_ctx, abi_long ctx_size);
  75/**
  76 * block_signals: block all signals while handling this guest syscall
  77 *
  78 * Block all signals, and arrange that the signal mask is returned to
  79 * its correct value for the guest before we resume execution of guest code.
  80 * If this function returns non-zero, then the caller should immediately
  81 * return -QEMU_ERESTARTSYS to the main loop, which will take the pending
  82 * signal and restart execution of the syscall.
  83 * If block_signals() returns zero, then the caller can continue with
  84 * emulation of the system call knowing that no signals can be taken
  85 * (and therefore that no race conditions will result).
  86 * This should only be called once, because if it is called a second time
  87 * it will always return non-zero. (Think of it like a mutex that can't
  88 * be recursively locked.)
  89 * Signals will be unblocked again by process_pending_signals().
  90 *
  91 * Return value: non-zero if there was a pending signal, zero if not.
  92 */
  93int block_signals(void); /* Returns non zero if signal pending */
  94
  95/**
  96 * process_sigsuspend_mask: read and apply syscall-local signal mask
  97 *
  98 * Read the guest signal mask from @sigset, length @sigsize.
  99 * Convert that to a host signal mask and save it to sigpending_mask.
 100 *
 101 * Return value: negative target errno, or zero;
 102 *               store &sigpending_mask into *pset on success.
 103 */
 104int process_sigsuspend_mask(sigset_t **pset, target_ulong sigset,
 105                            target_ulong sigsize);
 106
 107/**
 108 * finish_sigsuspend_mask: finish a sigsuspend-like syscall
 109 *
 110 * Set in_sigsuspend if we need to use the modified sigset
 111 * during process_pending_signals.
 112 */
 113static inline void finish_sigsuspend_mask(int ret)
 114{
 115    if (ret != -QEMU_ERESTARTSYS) {
 116        TaskState *ts = (TaskState *)thread_cpu->opaque;
 117        ts->in_sigsuspend = 1;
 118    }
 119}
 120
 121#endif
 122