From 394cf694273caf8ab8838588954d0fc2909ae2fa Mon Sep 17 00:00:00 2001 From: Warner Losh Date: Sat, 8 Jan 2022 23:59:42 -0700 Subject: bsd-user/signal.c: implement do_sigaction Implement the meat of the sigaction(2) system call with do_sigaction and helper routiner block_signals (which is also used to implemement signal masking so it's global). Signed-off-by: Stacey Son Signed-off-by: Kyle Evans Signed-off-by: Warner Losh Reviewed-by: Richard Henderson --- bsd-user/signal-common.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'bsd-user/signal-common.h') diff --git a/bsd-user/signal-common.h b/bsd-user/signal-common.h index 786ec592d1..7ff8e8f2e4 100644 --- a/bsd-user/signal-common.h +++ b/bsd-user/signal-common.h @@ -9,7 +9,29 @@ #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); -- cgit 1.4.1