/*
 * <signal.h> overlay for the MontaukOS git port.
 *
 * The libc supplies signal()/raise()/kill() and the signal numbers; this adds
 * the sigaction() family that git uses in a handful of places (fast-import's
 * SIGUSR1 checkpoint handler, sigchain's SIGPIPE and SIGINT handling).
 *
 * MontaukOS delivers only SIGINT, and has no signal masks: a handler is
 * either installed or it is not. sigaction() below is therefore a wrapper
 * around signal() that honours sa_handler and ignores sa_mask and sa_flags,
 * and the sigset_t operations manipulate a plain bitmask that nothing
 * consults. See montauk-compat.c.
 */
#ifndef _MONTAUK_GIT_SIGNAL_H_
#define _MONTAUK_GIT_SIGNAL_H_

#include_next <signal.h>

/* One past the highest signal number the libc names (SIGSTOP, 19). */
#define NSIG 32

typedef unsigned long sigset_t;

struct sigaction {
	sighandler_t sa_handler;
	sigset_t     sa_mask;
	int          sa_flags;
	void       (*sa_restorer)(void);
};

#define SA_RESTART   0x10000000
#define SA_NOCLDSTOP 0x00000001
#define SA_SIGINFO   0x00000004
#define SA_NODEFER   0x40000000
#define SA_RESETHAND 0x80000000

#define SIG_BLOCK   0
#define SIG_UNBLOCK 1
#define SIG_SETMASK 2

int sigemptyset(sigset_t *set);
int sigfillset(sigset_t *set);
int sigaddset(sigset_t *set, int signum);
int sigdelset(sigset_t *set, int signum);
int sigismember(const sigset_t *set, int signum);
int sigaction(int signum, const struct sigaction *act, struct sigaction *old);
int sigprocmask(int how, const sigset_t *set, sigset_t *old);

#endif /* _MONTAUK_GIT_SIGNAL_H_ */