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#ifndef _SIGNAL_H
#define _SIGNAL_H
#include <stdc_common.h>
typedef long sig_atomic_t; // there are no "asynchronous interrupts"
#define SIG_DFL ((void *)0)
#define SIG_IGN _sig_ign
#define SIG_ERR ((void *)-1)
typedef void (*_Sighandler)(int);
struct sigaction {
void (*sa_handler)(int);
#define sa_sigaction sa_handler
unsigned long sa_flags;
void (*sa_restorer)(void);
unsigned long sa_mask;
};
unsigned char _signal_restorer[] = {
0x48,0xb8,15,0,0,0,0,0,0,0, // mov rax, 15 (sigreturn)
0x0f,0x05 // syscall
};
#define _SIGNAL_HANDLERS 0xfff000
#define _LE64(x) (x)&0xff, ((x)>> 8)&0xff, ((x)>>16)&0xff, ((x)>>24)&0xff, \
((x)>>32)&0xff, ((x)>>40)&0xff, ((x)>>48)&0xff, (x)>>56
// we need to do this weird indirection because linux has a different
// calling convention from us.
unsigned char _signal_handler[] = {
// signal # passed in rdi
0x48,0x89,0xf8, // mov rax, rdi (signal #)
0x50, // push rax
0x50, // push rax (allocate space for return value)
0x48,0xb8,_LE64(_SIGNAL_HANDLERS), // mov rax, _SIGNAL_HANDLERS
0x48,0x89,0xc3, // mov rbx, rax
0x48,0x89,0xf8, // mov rax, rdi (signal #)
0x48,0xc1,0xe0,0x03, // shl rax, 3
0x48,0x01,0xd8, // add rax, rbx
0x48,0x89,0xc3, // mov rbx, rax
0x48,0x8b,0x03, // mov rax, [rbx]
0xff,0xd0, // call rax
0x48,0x81,0xc4,16,0,0,0, // add rsp, 16
0xc3 // ret
};
#define _SA_RESTORER 0x04000000
#define SA_SIGINFO 4
#define SA_RESETHAND 0x80000000
int __sigaction(int signum, const struct sigaction *act, struct sigaction *oldact) {
return __syscall(13, signum, act, oldact, 8, 0, 0);
}
void sigemptyset(unsigned long *set) {
*set = 0;
}
void _sig_ign(int signal) {
return;
}
static unsigned long _sig_mask = 0;
_Sighandler signal(int sig, _Sighandler func) {
void **handlers = _SIGNAL_HANDLERS;
_Sighandler ret = handlers[sig];
if (func == SIG_IGN) {
func = _sig_ign;
}
handlers[sig] = func;
if (func == SIG_DFL) {
_sig_mask &= ~(1ul << (sig-1));
} else {
_sig_mask |= 1ul << (sig-1);
}
struct sigaction act = {0};
act.sa_handler = func == SIG_DFL ? SIG_DFL : (void*)_signal_handler;
act.sa_mask = _sig_mask;
act.sa_flags = _SA_RESTORER;
act.sa_restorer = _signal_restorer;
__sigaction(sig, &act, NULL);
return ret;
}
int raise(int signal) {
return kill(getpid(), signal);
}
#define FPE_INTDIV 1
#define FPE_FLTDIV 3
#define __SI_MAX_SIZE 128
#if __WORDSIZE == 64
# define __SI_PAD_SIZE ((__SI_MAX_SIZE / sizeof (int)) - 4)
#else
# define __SI_PAD_SIZE ((__SI_MAX_SIZE / sizeof (int)) - 3)
#endif
#ifndef __SI_ALIGNMENT
# define __SI_ALIGNMENT /* nothing */
#endif
#ifndef __SI_BAND_TYPE
# define __SI_BAND_TYPE long int
#endif
#ifndef __SI_CLOCK_T
# define __SI_CLOCK_T __clock_t
#endif
#ifndef __SI_ERRNO_THEN_CODE
# define __SI_ERRNO_THEN_CODE 1
#endif
#ifndef __SI_HAVE_SIGSYS
# define __SI_HAVE_SIGSYS 1
#endif
#ifndef __SI_SIGFAULT_ADDL
# define __SI_SIGFAULT_ADDL /* nothing */
#endif
typedef int __pid_t;
typedef unsigned __uid_t;
union __sigval
{
int __sival_int;
void *__sival_ptr;
};
typedef union __sigval __sigval_t;
typedef long __clock_t;
typedef struct
{
int si_signo; /* Signal number. */
#if __SI_ERRNO_THEN_CODE
int si_errno; /* If non-zero, an errno value associated with
this signal, as defined in <errno.h>. */
int si_code; /* Signal code. */
#else
int si_code;
int si_errno;
#endif
#if __WORDSIZE == 64
int __pad0; /* Explicit padding. */
#endif
union
{
int _pad[__SI_PAD_SIZE];
/* kill(). */
struct
{
__pid_t si_pid; /* Sending process ID. */
__uid_t si_uid; /* Real user ID of sending process. */
} _kill;
/* POSIX.1b timers. */
struct
{
int si_tid; /* Timer ID. */
int si_overrun; /* Overrun count. */
__sigval_t si_sigval; /* Signal value. */
} _timer;
/* POSIX.1b signals. */
struct
{
__pid_t si_pid; /* Sending process ID. */
__uid_t si_uid; /* Real user ID of sending process. */
__sigval_t si_sigval; /* Signal value. */
} _rt;
/* SIGCHLD. */
struct
{
__pid_t si_pid; /* Which child. */
__uid_t si_uid; /* Real user ID of sending process. */
int si_status; /* Exit value or signal. */
__SI_CLOCK_T si_utime;
__SI_CLOCK_T si_stime;
} _sigchld;
/* SIGILL, SIGFPE, SIGSEGV, SIGBUS. */
struct
{
void *si_addr; /* Faulting insn/memory ref. */
__SI_SIGFAULT_ADDL
short int si_addr_lsb; /* Valid LSB of the reported address. */
union
{
/* used when si_code=SEGV_BNDERR */
struct
{
void *_lower;
void *_upper;
} _addr_bnd;
/* used when si_code=SEGV_PKUERR */
uint32_t _pkey;
} _bounds;
} _sigfault;
/* SIGPOLL. */
struct
{
__SI_BAND_TYPE si_band; /* Band event for SIGPOLL. */
int si_fd;
} _sigpoll;
/* SIGSYS. */
#if __SI_HAVE_SIGSYS
struct
{
void *_call_addr; /* Calling user insn. */
int _syscall; /* Triggering system call number. */
unsigned int _arch; /* AUDIT_ARCH_* of syscall. */
} _sigsys;
#endif
} _sifields;
} siginfo_t __SI_ALIGNMENT;
/* X/Open requires some more fields with fixed names. */
#define si_pid _sifields._kill.si_pid
#define si_uid _sifields._kill.si_uid
#define si_timerid _sifields._timer.si_tid
#define si_overrun _sifields._timer.si_overrun
#define si_status _sifields._sigchld.si_status
#define si_utime _sifields._sigchld.si_utime
#define si_stime _sifields._sigchld.si_stime
#define si_value _sifields._rt.si_sigval
#define si_int _sifields._rt.si_sigval.sival_int
#define si_ptr _sifields._rt.si_sigval.sival_ptr
#define si_addr _sifields._sigfault.si_addr
#define si_addr_lsb _sifields._sigfault.si_addr_lsb
#define si_lower _sifields._sigfault._bounds._addr_bnd._lower
#define si_upper _sifields._sigfault._bounds._addr_bnd._upper
#define si_pkey _sifields._sigfault._bounds._pkey
#define si_band _sifields._sigpoll.si_band
#define si_fd _sifields._sigpoll.si_fd
#if __SI_HAVE_SIGSYS
# define si_call_addr _sifields._sigsys._call_addr
# define si_syscall _sifields._sigsys._syscall
# define si_arch _sifields._sigsys._arch
#endif
#endif // _SIGNAL_H
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