blob: 77d7c7a78b7f72778630633bcbb5a785ce82703e [file] [log] [blame]
* Emulation of BSD signals
* Copyright (c) 2013 Stacey Son
* SPDX-License-Identifier: GPL-2.0-or-later
* block_signals: block all signals while handling this guest syscall
* Block all signals, and arrange that the signal mask is returned to
* its correct value for the guest before we resume execution of guest code.
* If this function returns non-zero, then the caller should immediately
* return -TARGET_ERESTARTSYS to the main loop, which will take the pending
* signal and restart execution of the syscall.
* If block_signals() returns zero, then the caller can continue with
* emulation of the system call knowing that no signals can be taken
* (and therefore that no race conditions will result).
* This should only be called once, because if it is called a second time
* it will always return non-zero. (Think of it like a mutex that can't
* be recursively locked.)
* Signals will be unblocked again by process_pending_signals().
* Return value: non-zero if there was a pending signal, zero if not.
int block_signals(void); /* Returns non zero if signal pending */
long do_rt_sigreturn(CPUArchState *env);
int do_sigaction(int sig, const struct target_sigaction *act,
struct target_sigaction *oact);
abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
long do_sigreturn(CPUArchState *env, abi_ulong addr);
void force_sig_fault(int sig, int code, abi_ulong addr);
void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
int host_to_target_signal(int sig);
void host_to_target_sigset(target_sigset_t *d, const sigset_t *s);
void process_pending_signals(CPUArchState *env);
void queue_signal(CPUArchState *env, int sig, int si_type,
target_siginfo_t *info);
void signal_init(void);
int target_to_host_signal(int sig);
void target_to_host_sigset(sigset_t *d, const target_sigset_t *s);
* Within QEMU the top 8 bits of si_code indicate which of the parts of the
* union in target_siginfo is valid. This only applies between
* host_to_target_siginfo_noswap() and tswap_siginfo(); it does not appear
* either within host siginfo_t or in target_siginfo structures which we get
* from the guest userspace program. Linux kernels use this internally, but BSD
* kernels don't do this, but its a useful abstraction.
* The linux-user version of this uses the top 16 bits, but FreeBSD's SI_USER
* and other signal independent SI_ codes have bit 16 set, so we only use the top
* byte instead.
* For FreeBSD, we have si_pid, si_uid, si_status, and si_addr always. Linux and
* {Open,Net}BSD have a different approach (where their reason field is larger,
* but whose siginfo has fewer fields always).
* QEMU_SI_CAPSICUM is currently only FreeBSD 14 current only, so only define
* it where _capsicum is available.
#define QEMU_SI_NOINFO 0 /* nothing other than si_signo valid */
#define QEMU_SI_FAULT 1 /* _fault is valid in _reason */
#define QEMU_SI_TIMER 2 /* _timer is valid in _reason */
#define QEMU_SI_MESGQ 3 /* _mesgq is valid in _reason */
#define QEMU_SI_POLL 4 /* _poll is valid in _reason */
#if defined(__FreeBSD_version) && __FreeBSD_version >= 1400026
#define QEMU_SI_CAPSICUM 5 /* _capsicum is valid in _reason */