signal.c.svn-base

我们自己开发的一个OSEK操作系统！不知道可不可以？

    /* XXX: test errors */
    if(uoss_addr)
    {
        __put_user(target_sigaltstack_used.ss_sp, &oss.ss_sp);
        __put_user(target_sigaltstack_used.ss_size, &oss.ss_size);
        __put_user(sas_ss_flags(sp), &oss.ss_flags);
    }

    if(uss_addr)
    {
        struct target_sigaltstack *uss;
        struct target_sigaltstack ss;

	ret = -TARGET_EFAULT;
        if (!lock_user_struct(VERIFY_READ, uss, uss_addr, 1)
	    || __get_user(ss.ss_sp, &uss->ss_sp)
	    || __get_user(ss.ss_size, &uss->ss_size)
	    || __get_user(ss.ss_flags, &uss->ss_flags))
            goto out;
        unlock_user_struct(uss, uss_addr, 0);

	ret = -TARGET_EPERM;
	if (on_sig_stack(sp))
            goto out;

	ret = -TARGET_EINVAL;
	if (ss.ss_flags != TARGET_SS_DISABLE
            && ss.ss_flags != TARGET_SS_ONSTACK
            && ss.ss_flags != 0)
            goto out;

	if (ss.ss_flags == TARGET_SS_DISABLE) {
            ss.ss_size = 0;
            ss.ss_sp = 0;
	} else {
            ret = -TARGET_ENOMEM;
            if (ss.ss_size < MINSIGSTKSZ)
                goto out;
	}

        target_sigaltstack_used.ss_sp = ss.ss_sp;
        target_sigaltstack_used.ss_size = ss.ss_size;
    }

    if (uoss_addr) {
        ret = -TARGET_EFAULT;
        if (copy_to_user(uoss_addr, &oss, sizeof(oss)))
            goto out;
    }

    ret = 0;
out:
    return ret;
}

/* do_sigaction() return host values and errnos */
int do_sigaction(int sig, const struct target_sigaction *act,
                 struct target_sigaction *oact)
{
    struct emulated_sigaction *k;
    struct sigaction act1;
    int host_sig;
    int ret = 0;

    if (sig < 1 || sig > TARGET_NSIG || sig == SIGKILL || sig == SIGSTOP)
        return -EINVAL;
    k = &sigact_table[sig - 1];
#if defined(DEBUG_SIGNAL)
    fprintf(stderr, "sigaction sig=%d act=0x%08x, oact=0x%08x\n",
            sig, (int)act, (int)oact);
#endif
    if (oact) {
        oact->_sa_handler = tswapl(k->sa._sa_handler);
        oact->sa_flags = tswapl(k->sa.sa_flags);
#if !defined(TARGET_MIPS)
        oact->sa_restorer = tswapl(k->sa.sa_restorer);
#endif
        oact->sa_mask = k->sa.sa_mask;
    }
    if (act) {
        k->sa._sa_handler = tswapl(act->_sa_handler);
        k->sa.sa_flags = tswapl(act->sa_flags);
#if !defined(TARGET_MIPS)
        k->sa.sa_restorer = tswapl(act->sa_restorer);
#endif
        k->sa.sa_mask = act->sa_mask;

        /* we update the host linux signal state */
        host_sig = target_to_host_signal(sig);
        if (host_sig != SIGSEGV && host_sig != SIGBUS) {
            sigfillset(&act1.sa_mask);
            act1.sa_flags = SA_SIGINFO;
            if (k->sa.sa_flags & TARGET_SA_RESTART)
                act1.sa_flags |= SA_RESTART;
            /* NOTE: it is important to update the host kernel signal
               ignore state to avoid getting unexpected interrupted
               syscalls */
            if (k->sa._sa_handler == TARGET_SIG_IGN) {
                act1.sa_sigaction = (void *)SIG_IGN;
            } else if (k->sa._sa_handler == TARGET_SIG_DFL) {
                act1.sa_sigaction = (void *)SIG_DFL;
            } else {
                act1.sa_sigaction = host_signal_handler;
            }
            ret = sigaction(host_sig, &act1, NULL);
        }
    }
    return ret;
}

#ifndef offsetof
#define offsetof(type, field) ((size_t) &((type *)0)->field)
#endif

static inline int copy_siginfo_to_user(target_siginfo_t *tinfo,
                                       const target_siginfo_t *info)
{
    tswap_siginfo(tinfo, info);
    return 0;
}

static inline int current_exec_domain_sig(int sig)
{
    return /* current->exec_domain && current->exec_domain->signal_invmap
	      && sig < 32 ? current->exec_domain->signal_invmap[sig] : */ sig;
}

#if defined(TARGET_I386) && TARGET_ABI_BITS == 32

/* from the Linux kernel */

struct target_fpreg {
	uint16_t significand[4];
	uint16_t exponent;
};

struct target_fpxreg {
	uint16_t significand[4];
	uint16_t exponent;
	uint16_t padding[3];
};

struct target_xmmreg {
	abi_ulong element[4];
};

struct target_fpstate {
	/* Regular FPU environment */
        abi_ulong       cw;
        abi_ulong       sw;
        abi_ulong       tag;
        abi_ulong       ipoff;
        abi_ulong       cssel;
        abi_ulong       dataoff;
        abi_ulong       datasel;
	struct target_fpreg	_st[8];
	uint16_t	status;
	uint16_t	magic;		/* 0xffff = regular FPU data only */

	/* FXSR FPU environment */
        abi_ulong       _fxsr_env[6];   /* FXSR FPU env is ignored */
        abi_ulong       mxcsr;
        abi_ulong       reserved;
	struct target_fpxreg	_fxsr_st[8];	/* FXSR FPU reg data is ignored */
	struct target_xmmreg	_xmm[8];
        abi_ulong       padding[56];
};

#define X86_FXSR_MAGIC		0x0000

struct target_sigcontext {
	uint16_t gs, __gsh;
	uint16_t fs, __fsh;
	uint16_t es, __esh;
	uint16_t ds, __dsh;
        abi_ulong edi;
        abi_ulong esi;
        abi_ulong ebp;
        abi_ulong esp;
        abi_ulong ebx;
        abi_ulong edx;
        abi_ulong ecx;
        abi_ulong eax;
        abi_ulong trapno;
        abi_ulong err;
        abi_ulong eip;
	uint16_t cs, __csh;
        abi_ulong eflags;
        abi_ulong esp_at_signal;
	uint16_t ss, __ssh;
        abi_ulong fpstate; /* pointer */
        abi_ulong oldmask;
        abi_ulong cr2;
};

struct target_ucontext {
        abi_ulong         tuc_flags;
        abi_ulong         tuc_link;
	target_stack_t	  tuc_stack;
	struct target_sigcontext tuc_mcontext;
	target_sigset_t	  tuc_sigmask;	/* mask last for extensibility */
};

struct sigframe
{
    abi_ulong pretcode;
    int sig;
    struct target_sigcontext sc;
    struct target_fpstate fpstate;
    abi_ulong extramask[TARGET_NSIG_WORDS-1];
    char retcode[8];
};

struct rt_sigframe
{
    abi_ulong pretcode;
    int sig;
    abi_ulong pinfo;
    abi_ulong puc;
    struct target_siginfo info;
    struct target_ucontext uc;
    struct target_fpstate fpstate;
    char retcode[8];
};

/*
 * Set up a signal frame.
 */

/* XXX: save x87 state */
static int
setup_sigcontext(struct target_sigcontext *sc, struct target_fpstate *fpstate,
		 CPUX86State *env, abi_ulong mask, abi_ulong fpstate_addr)
{
	int err = 0;
        uint16_t magic;

	/* already locked in setup_frame() */
	err |= __put_user(env->segs[R_GS].selector, (unsigned int *)&sc->gs);
	err |= __put_user(env->segs[R_FS].selector, (unsigned int *)&sc->fs);
	err |= __put_user(env->segs[R_ES].selector, (unsigned int *)&sc->es);
	err |= __put_user(env->segs[R_DS].selector, (unsigned int *)&sc->ds);
	err |= __put_user(env->regs[R_EDI], &sc->edi);
	err |= __put_user(env->regs[R_ESI], &sc->esi);
	err |= __put_user(env->regs[R_EBP], &sc->ebp);
	err |= __put_user(env->regs[R_ESP], &sc->esp);
	err |= __put_user(env->regs[R_EBX], &sc->ebx);
	err |= __put_user(env->regs[R_EDX], &sc->edx);
	err |= __put_user(env->regs[R_ECX], &sc->ecx);
	err |= __put_user(env->regs[R_EAX], &sc->eax);
	err |= __put_user(env->exception_index, &sc->trapno);
	err |= __put_user(env->error_code, &sc->err);
	err |= __put_user(env->eip, &sc->eip);
	err |= __put_user(env->segs[R_CS].selector, (unsigned int *)&sc->cs);
	err |= __put_user(env->eflags, &sc->eflags);
	err |= __put_user(env->regs[R_ESP], &sc->esp_at_signal);
	err |= __put_user(env->segs[R_SS].selector, (unsigned int *)&sc->ss);

        cpu_x86_fsave(env, fpstate_addr, 1);
        fpstate->status = fpstate->sw;
        magic = 0xffff;
        err |= __put_user(magic, &fpstate->magic);
        err |= __put_user(fpstate_addr, &sc->fpstate);

	/* non-iBCS2 extensions.. */
	err |= __put_user(mask, &sc->oldmask);
	err |= __put_user(env->cr[2], &sc->cr2);
	return err;
}

/*
 * Determine which stack to use..
 */

static inline abi_ulong
get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size)
{
	unsigned long esp;

	/* Default to using normal stack */
	esp = env->regs[R_ESP];
	/* This is the X/Open sanctioned signal stack switching.  */
        if (ka->sa.sa_flags & TARGET_SA_ONSTACK) {
            if (sas_ss_flags(esp) == 0)
                esp = target_sigaltstack_used.ss_sp + target_sigaltstack_used.ss_size;
        }

	/* This is the legacy signal stack switching. */
	else
        if ((env->segs[R_SS].selector & 0xffff) != __USER_DS &&
            !(ka->sa.sa_flags & TARGET_SA_RESTORER) &&
            ka->sa.sa_restorer) {
            esp = (unsigned long) ka->sa.sa_restorer;
	}
        return (esp - frame_size) & -8ul;
}

/* compare linux/arch/i386/kernel/signal.c:setup_frame() */
static void setup_frame(int sig, struct emulated_sigaction *ka,
			target_sigset_t *set, CPUX86State *env)
{
	abi_ulong frame_addr;
	struct sigframe *frame;
	int i, err = 0;

	frame_addr = get_sigframe(ka, env, sizeof(*frame));

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
		goto give_sigsegv;

	err |= __put_user(current_exec_domain_sig(sig),
		          &frame->sig);
	if (err)
		goto give_sigsegv;

	setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0],
                         frame_addr + offsetof(struct sigframe, fpstate));
	if (err)
		goto give_sigsegv;

        for(i = 1; i < TARGET_NSIG_WORDS; i++) {
            if (__put_user(set->sig[i], &frame->extramask[i - 1]))
                goto give_sigsegv;
        }

	/* Set up to return from userspace.  If provided, use a stub
	   already in userspace.  */
	if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
		err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
	} else {
                uint16_t val16;
                abi_ulong retcode_addr;
                retcode_addr = frame_addr + offsetof(struct sigframe, retcode);
		err |= __put_user(retcode_addr, &frame->pretcode);
		/* This is popl %eax ; movl $,%eax ; int $0x80 */
                val16 = 0xb858;
		err |= __put_user(val16, (uint16_t *)(frame->retcode+0));
		err |= __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2));
                val16 = 0x80cd;
		err |= __put_user(val16, (uint16_t *)(frame->retcode+6));
	}

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	env->regs[R_ESP] = frame_addr;
	env->eip = ka->sa._sa_handler;

        cpu_x86_load_seg(env, R_DS, __USER_DS);
        cpu_x86_load_seg(env, R_ES, __USER_DS);
        cpu_x86_load_seg(env, R_SS, __USER_DS);
        cpu_x86_load_seg(env, R_CS, __USER_CS);
	env->eflags &= ~TF_MASK;

	unlock_user_struct(frame, frame_addr, 1);

	return;

give_sigsegv:
	unlock_user_struct(frame, frame_addr, 1);
	if (sig == TARGET_SIGSEGV)
		ka->sa._sa_handler = TARGET_SIG_DFL;
	force_sig(TARGET_SIGSEGV /* , current */);
}

/* compare linux/arch/i386/kernel/signal.c:setup_rt_frame() */
static void setup_rt_frame(int sig, struct emulated_sigaction *ka,
                           target_siginfo_t *info,
			   target_sigset_t *set, CPUX86State *env)
{
        abi_ulong frame_addr, addr;
	struct rt_sigframe *frame;
	int i, err = 0;

	frame_addr = get_sigframe(ka, env, sizeof(*frame));

	if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
		goto give_sigsegv;

	err |= __put_user(current_exec_domain_sig(sig),
			  &frame->sig);
        addr = frame_addr + offsetof(struct rt_sigframe, info);
	err |= __put_user(addr, &frame->pinfo);
        addr = frame_addr + offsetof(struct rt_sigframe, uc);
	err |= __put_user(addr, &frame->puc);
	err |= copy_siginfo_to_user(&frame->info, info);
	if (err)
		goto give_sigsegv;

	/* Create the ucontext.  */
	err |= __put_user(0, &frame->uc.tuc_flags);
	err |= __put_user(0, &frame->uc.tuc_link);
	err |= __put_user(target_sigaltstack_used.ss_sp,
			  &frame->uc.tuc_stack.ss_sp);
	err |= __put_user(sas_ss_flags(get_sp_from_cpustate(env)),
			  &frame->uc.tuc_stack.ss_flags);
	err |= __put_user(target_sigaltstack_used.ss_size,
			  &frame->uc.tuc_stack.ss_size);
	err |= setup_sigcontext(&frame->uc.tuc_mcontext, &frame->fpstate,
			        env, set->sig[0], 
                                frame_addr + offsetof(struct rt_sigframe, fpstate));
        for(i = 0; i < TARGET_NSIG_WORDS; i++) {
            if (__put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]))
                goto give_sigsegv;
        }

	/* Set up to return from userspace.  If provided, use a stub
	   already in userspace.  */
	if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
		err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
	} else {
                uint16_t val16;
                addr = frame_addr + offsetof(struct rt_sigframe, retcode);
		err |= __put_user(addr, &frame->pretcode);
		/* This is movl $,%eax ; int $0x80 */
                err |= __put_user(0xb8, (char *)(frame->retcode+0));
		err |= __put_user(TARGET_NR_rt_sigreturn, (int *)(frame->retcode+1));
                val16 = 0x80cd;
                err |= __put_user(val16, (uint16_t *)(frame->retcode+5));
	}

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	env->regs[R_ESP] = frame_addr;
	env->eip = ka->sa._sa_handler;

        cpu_x86_load_seg(env, R_DS, __USER_DS);
        cpu_x86_load_seg(env, R_ES, __USER_DS);
        cpu_x86_load_seg(env, R_SS, __USER_DS);
        cpu_x86_load_seg(env, R_CS, __USER_CS);
	env->eflags &= ~TF_MASK;

	unlock_user_struct(frame, frame_addr, 1);

	return;

give_sigsegv:
	unlock_user_struct(frame, frame_addr, 1);
	if (sig == TARGET_SIGSEGV)
		ka->sa._sa_handler = TARGET_SIG_DFL;