/* -*- mode:c; c-file-style:"k&r"; c-basic-offset: 4; tab-width:4; indent-tabs-mode:nil; mode:auto-fill; fill-column:78; -*- */
/* vim: set ts=4 sw=4 et tw=78 fo=cqt wm=0: */

#ifndef _SHIM_SIGNAL_H_
#define _SHIM_SIGNAL_H_

#include <shim_types.h>
#include <shim_defs.h>
#include <shim_thread.h>

struct shim_signal_handle {
    /* sigaction */
    struct __kernel_sigaction * action;
};

# define BITS_PER_WORD sizeof(unsigned long)
/* The standard def of this macro is dumb */
#undef _SIGSET_NWORDS
# define _SIGSET_NWORDS (NUM_SIGS / BITS_PER_WORD)

/* Return a mask that includes the bit for SIG only.  */
# define __sigmask(sig)                                                \
    (((unsigned long int) 1) << (((sig) - 1) % (8 * sizeof (unsigned long int))))

/* Return the word index for SIG.  */
# define __sigword(sig) (((sig) - 1) / (8 * sizeof (unsigned long int)))

/* Clear all signals from SET.  */
#  define __sigemptyset(set)                                    \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            __sigset_t *__set = (set);                          \
            while (--__cnt >= 0) __set->__val[__cnt] = 0;       \
            0; }))

/* Set all signals in SET.  */
#  define __sigfillset(set)                                     \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            __sigset_t *__set = (set);                          \
            while (--__cnt >= 0) __set->__val[__cnt] = ~0UL;    \
            0; }))

#   define __sigisemptyset(set)                                 \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            const __sigset_t *__set = (set);                    \
            int __ret = __set->__val[--__cnt];                  \
            while (!__ret && --__cnt >= 0)                      \
                __ret = __set->__val[__cnt];                    \
            __ret == 0; }))

#   define __sigandset(dest, left, right)                       \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            __sigset_t *__dest = (dest);                        \
            const __sigset_t *__left = (left);                  \
            const __sigset_t *__right = (right);                \
            while (--__cnt >= 0)                                \
                __dest->__val[__cnt] = (__left->__val[__cnt]    \
                                        & __right->__val[__cnt]); \
            0; }))

#   define __sigorset(dest, left, right)                        \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            __sigset_t *__dest = (dest);                        \
            const __sigset_t *__left = (left);                  \
            const __sigset_t *__right = (right);                \
            while (--__cnt >= 0)                                \
                __dest->__val[__cnt] = (__left->__val[__cnt]    \
                                        | __right->__val[__cnt]); \
            0; }))

#   define __signotset(dest, left, right)                       \
    (__extension__ ({ int __cnt = _SIGSET_NWORDS;               \
            __sigset_t *__dest = (dest);                        \
            const __sigset_t *__left = (left);                  \
            const __sigset_t *__right = (right);                \
            while (--__cnt >= 0)                                \
                __dest->__val[__cnt] = (__left->__val[__cnt]    \
                                        & ~__right->__val[__cnt]); \
            0; }))

#  define __SIGSETFN(NAME, BODY, CONST)                     \
    static inline int                                       \
    NAME (CONST __sigset_t *__set, int __sig)               \
    {                                                       \
        unsigned long int __mask = __sigmask (__sig);       \
        unsigned long int __word = __sigword (__sig);       \
        return BODY;                                        \
    }

__SIGSETFN (shim_sigismember, (__set->__val[__word] & __mask) ? 1 : 0, __const)
__SIGSETFN (shim_sigaddset, ((__set->__val[__word] |= __mask), 0), )
__SIGSETFN (shim_sigdelset, ((__set->__val[__word] &= ~__mask), 0), )

#define __sigismember shim_sigismember
#define __sigaddset   shim_sigaddset
#define __sigdelset   shim_sigdelset

/* NB: Check shim_signal.c if this changes.  Some memset(0) elision*/
struct shim_signal {
    siginfo_t   info;
    bool        context_stored;
    ucontext_t  context;
    PAL_CONTEXT * pal_context;
};

#define MAX_SIGNAL_LOG      32

struct shim_signal_log {
    struct atomic_int head, tail;
    struct shim_signal * logs[MAX_SIGNAL_LOG];
};

extern const char * const siglist[NUM_KNOWN_SIGS + 1];

static_inline const char * signal_name (int sig)
{
    if (sig <= NUM_KNOWN_SIGS)
        return siglist[sig];

    if (sig >= NUM_SIGS)
        return "BAD SIGNAL";

    char * str = __alloca(6);

    str[0] = 'S';
    str[1] = 'I';
    str[2] = 'G';
    str[3] = '0' + sig / 10;
    str[4] = '0' + sig % 10;
    str[5] = 0;

    return str;
}

struct shim_thread;

int init_signal (void);

void __store_context (shim_tcb_t * tcb, PAL_CONTEXT * pal_context,
                      struct shim_signal * signal);

void append_signal (struct shim_thread * thread, int sig, siginfo_t * info,
                    bool wakeup);
void deliver_signal (siginfo_t * info, PAL_CONTEXT * context);

__sigset_t * get_sig_mask (struct shim_thread * thread);
__sigset_t * set_sig_mask (struct shim_thread * thread,
                           const __sigset_t * new_set);

int do_kill_thread (IDTYPE sender, IDTYPE tgid, IDTYPE tid, int sig,
                    bool use_ipc);
int do_kill_proc (IDTYPE sender, IDTYPE tgid, int sig, bool use_ipc);
int do_kill_pgroup (IDTYPE sender, IDTYPE pgid, int sig, bool use_ipc);

int broadcast_signal (IDTYPE sender, int sig);
int kill_all_threads (struct shim_thread * cur, IDTYPE sender, int sig);

#endif /* _SHIM_SIGNAL_H_ */