diff options
Diffstat (limited to 'bsd-user/signal-common.h')
-rw-r--r-- | bsd-user/signal-common.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/bsd-user/signal-common.h b/bsd-user/signal-common.h new file mode 100644 index 0000000000..7ff8e8f2e4 --- /dev/null +++ b/bsd-user/signal-common.h @@ -0,0 +1,70 @@ +/* + * Emulation of BSD signals + * + * Copyright (c) 2013 Stacey Son + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#ifndef SIGNAL_COMMON_H +#define SIGNAL_COMMON_H + +/** + * 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); +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 kenrels 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 indepenent 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). + */ +#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 */ +#define QEMU_SI_CAPSICUM 5 /* _capsicum is valid in _reason */ + +#endif |