signal.c

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static int
setup_return(CPUState *env, struct emulated_sigaction *ka,
	     target_ulong *rc, void *frame, int usig)
{
	target_ulong handler = (target_ulong)ka->sa._sa_handler;
	target_ulong retcode;
	int thumb = 0;
#if defined(TARGET_CONFIG_CPU_32)
#if 0
	target_ulong cpsr = env->cpsr;

	/*
	 * Maybe we need to deliver a 32-bit signal to a 26-bit task.
	 */
	if (ka->sa.sa_flags & SA_THIRTYTWO)
		cpsr = (cpsr & ~MODE_MASK) | USR_MODE;

#ifdef CONFIG_ARM_THUMB
	if (elf_hwcap & HWCAP_THUMB) {
		/*
		 * The LSB of the handler determines if we're going to
		 * be using THUMB or ARM mode for this signal handler.
		 */
		thumb = handler & 1;

		if (thumb)
			cpsr |= T_BIT;
		else
			cpsr &= ~T_BIT;
	}
#endif
#endif
#endif /* TARGET_CONFIG_CPU_32 */

	if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
		retcode = (target_ulong)ka->sa.sa_restorer;
	} else {
		unsigned int idx = thumb;

		if (ka->sa.sa_flags & TARGET_SA_SIGINFO)
			idx += 2;

		if (__put_user(retcodes[idx], rc))
			return 1;
#if 0
		flush_icache_range((target_ulong)rc,
				   (target_ulong)(rc + 1));
#endif
		retcode = ((target_ulong)rc) + thumb;
	}

	env->regs[0] = usig;
	env->regs[13] = h2g(frame);
	env->regs[14] = retcode;
	env->regs[15] = handler & (thumb ? ~1 : ~3);

#if 0
#ifdef TARGET_CONFIG_CPU_32
	env->cpsr = cpsr;
#endif
#endif

	return 0;
}

static void setup_frame(int usig, struct emulated_sigaction *ka,
			target_sigset_t *set, CPUState *regs)
{
	struct sigframe *frame = get_sigframe(ka, regs, sizeof(*frame));
	int i, err = 0;

	err |= setup_sigcontext(&frame->sc, /*&frame->fpstate,*/ regs, set->sig[0]);

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

	if (err == 0)
            err = setup_return(regs, ka, &frame->retcode, frame, usig);
        //	return err;
}

static void setup_rt_frame(int usig, struct emulated_sigaction *ka, 
                           target_siginfo_t *info,
			   target_sigset_t *set, CPUState *env)
{
	struct rt_sigframe *frame = get_sigframe(ka, env, sizeof(*frame));
	int i, err = 0;

	if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
            return /* 1 */;

	__put_user_error(&frame->info, (target_ulong *)&frame->pinfo, err);
	__put_user_error(&frame->uc, (target_ulong *)&frame->puc, err);
	err |= copy_siginfo_to_user(&frame->info, info);

	/* Clear all the bits of the ucontext we don't use.  */
	memset(&frame->uc, 0, offsetof(struct target_ucontext, tuc_mcontext));

	err |= setup_sigcontext(&frame->uc.tuc_mcontext, /*&frame->fpstate,*/
				env, set->sig[0]);
        for(i = 0; i < TARGET_NSIG_WORDS; i++) {
            if (__put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]))
                return;
        }

	if (err == 0)
		err = setup_return(env, ka, &frame->retcode, frame, usig);

	if (err == 0) {
		/*
		 * For realtime signals we must also set the second and third
		 * arguments for the signal handler.
		 *   -- Peter Maydell <[e-mail]> 2000-12-06
		 */
            env->regs[1] = (target_ulong)frame->pinfo;
            env->regs[2] = (target_ulong)frame->puc;
	}

        //	return err;
}

static int
restore_sigcontext(CPUState *env, struct target_sigcontext *sc)
{
	int err = 0;
        uint32_t cpsr;

	__get_user_error(env->regs[0], &sc->arm_r0, err);
	__get_user_error(env->regs[1], &sc->arm_r1, err);
	__get_user_error(env->regs[2], &sc->arm_r2, err);
	__get_user_error(env->regs[3], &sc->arm_r3, err);
	__get_user_error(env->regs[4], &sc->arm_r4, err);
	__get_user_error(env->regs[5], &sc->arm_r5, err);
	__get_user_error(env->regs[6], &sc->arm_r6, err);
	__get_user_error(env->regs[7], &sc->arm_r7, err);
	__get_user_error(env->regs[8], &sc->arm_r8, err);
	__get_user_error(env->regs[9], &sc->arm_r9, err);
	__get_user_error(env->regs[10], &sc->arm_r10, err);
	__get_user_error(env->regs[11], &sc->arm_fp, err);
	__get_user_error(env->regs[12], &sc->arm_ip, err);
	__get_user_error(env->regs[13], &sc->arm_sp, err);
	__get_user_error(env->regs[14], &sc->arm_lr, err);
	__get_user_error(env->regs[15], &sc->arm_pc, err);
#ifdef TARGET_CONFIG_CPU_32
	__get_user_error(cpsr, &sc->arm_cpsr, err);
        cpsr_write(env, cpsr, 0xffffffff);
#endif

	err |= !valid_user_regs(env);

	return err;
}

long do_sigreturn(CPUState *env)
{
	struct sigframe *frame;
	target_sigset_t set;
        sigset_t host_set;
        int i;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

	frame = (struct sigframe *)g2h(env->regs[13]);

#if 0
	if (verify_area(VERIFY_READ, frame, sizeof (*frame)))
		goto badframe;
#endif
	if (__get_user(set.sig[0], &frame->sc.oldmask))
            goto badframe;
        for(i = 1; i < TARGET_NSIG_WORDS; i++) {
            if (__get_user(set.sig[i], &frame->extramask[i - 1]))
                goto badframe;
        }

        target_to_host_sigset_internal(&host_set, &set);
        sigprocmask(SIG_SETMASK, &host_set, NULL);

	if (restore_sigcontext(env, &frame->sc))
		goto badframe;

#if 0
	/* Send SIGTRAP if we're single-stepping */
	if (ptrace_cancel_bpt(current))
		send_sig(SIGTRAP, current, 1);
#endif
	return env->regs[0];

badframe:
        force_sig(SIGSEGV /* , current */);
	return 0;
}

long do_rt_sigreturn(CPUState *env)
{
	struct rt_sigframe *frame;
        sigset_t host_set;

	/*
	 * Since we stacked the signal on a 64-bit boundary,
	 * then 'sp' should be word aligned here.  If it's
	 * not, then the user is trying to mess with us.
	 */
	if (env->regs[13] & 7)
		goto badframe;

	frame = (struct rt_sigframe *)env->regs[13];

#if 0
	if (verify_area(VERIFY_READ, frame, sizeof (*frame)))
		goto badframe;
#endif
        target_to_host_sigset(&host_set, &frame->uc.tuc_sigmask);
        sigprocmask(SIG_SETMASK, &host_set, NULL);

	if (restore_sigcontext(env, &frame->uc.tuc_mcontext))
		goto badframe;

#if 0
	/* Send SIGTRAP if we're single-stepping */
	if (ptrace_cancel_bpt(current))
		send_sig(SIGTRAP, current, 1);
#endif
	return env->regs[0];

badframe:
        force_sig(SIGSEGV /* , current */);
	return 0;
}

#elif defined(TARGET_SPARC)

#define __SUNOS_MAXWIN   31

/* This is what SunOS does, so shall I. */
struct target_sigcontext {
        target_ulong sigc_onstack;      /* state to restore */

        target_ulong sigc_mask;         /* sigmask to restore */
        target_ulong sigc_sp;           /* stack pointer */
        target_ulong sigc_pc;           /* program counter */
        target_ulong sigc_npc;          /* next program counter */
        target_ulong sigc_psr;          /* for condition codes etc */
        target_ulong sigc_g1;           /* User uses these two registers */
        target_ulong sigc_o0;           /* within the trampoline code. */

        /* Now comes information regarding the users window set
         * at the time of the signal.
         */
        target_ulong sigc_oswins;       /* outstanding windows */

        /* stack ptrs for each regwin buf */
        char *sigc_spbuf[__SUNOS_MAXWIN];

        /* Windows to restore after signal */
        struct {
                target_ulong locals[8];
                target_ulong ins[8];
        } sigc_wbuf[__SUNOS_MAXWIN];
};
/* A Sparc stack frame */
struct sparc_stackf {
        target_ulong locals[8];
        target_ulong ins[6];
        struct sparc_stackf *fp;
        target_ulong callers_pc;
        char *structptr;
        target_ulong xargs[6];
        target_ulong xxargs[1];
};

typedef struct {
        struct {
                target_ulong psr;
                target_ulong pc;
                target_ulong npc;
                target_ulong y;
                target_ulong u_regs[16]; /* globals and ins */
        }               si_regs;
        int             si_mask;
} __siginfo_t;

typedef struct {
        unsigned   long si_float_regs [32];
        unsigned   long si_fsr;
        unsigned   long si_fpqdepth;
        struct {
                unsigned long *insn_addr;
                unsigned long insn;
        } si_fpqueue [16];
} qemu_siginfo_fpu_t;


struct target_signal_frame {
	struct sparc_stackf	ss;
	__siginfo_t		info;
	qemu_siginfo_fpu_t 	*fpu_save;
	target_ulong		insns[2] __attribute__ ((aligned (8)));
	target_ulong		extramask[TARGET_NSIG_WORDS - 1];
	target_ulong		extra_size; /* Should be 0 */
	qemu_siginfo_fpu_t	fpu_state;
};
struct target_rt_signal_frame {
	struct sparc_stackf	ss;
	siginfo_t		info;
	target_ulong		regs[20];
	sigset_t		mask;
	qemu_siginfo_fpu_t 	*fpu_save;
	unsigned int		insns[2];
	stack_t			stack;
	unsigned int		extra_size; /* Should be 0 */
	qemu_siginfo_fpu_t	fpu_state;
};

#define UREG_O0        16
#define UREG_O6        22
#define UREG_I0        0
#define UREG_I1        1
#define UREG_I2        2
#define UREG_I6        6
#define UREG_I7        7
#define UREG_L0	       8
#define UREG_FP        UREG_I6
#define UREG_SP        UREG_O6

static inline void *get_sigframe(struct emulated_sigaction *sa, CPUState *env, unsigned long framesize)
{
	unsigned long sp;

	sp = env->regwptr[UREG_FP];
#if 0

	/* This is the X/Open sanctioned signal stack switching.  */
	if (sa->sa_flags & TARGET_SA_ONSTACK) {
		if (!on_sig_stack(sp) && !((current->sas_ss_sp + current->sas_ss_size) & 7))
			sp = current->sas_ss_sp + current->sas_ss_size;
	}
#endif
	return g2h(sp - framesize);
}

static int
setup___siginfo(__siginfo_t *si, CPUState *env, target_ulong mask)
{
	int err = 0, i;

	err |= __put_user(env->psr, &si->si_regs.psr);
	err |= __put_user(env->pc, &si->si_regs.pc);
	err |= __put_user(env->npc, &si->si_regs.npc);
	err |= __put_user(env->y, &si->si_regs.y);
	for (i=0; i < 8; i++) {
		err |= __put_user(env->gregs[i], &si->si_regs.u_regs[i]);
	}
	for (i=0; i < 8; i++) {
		err |= __put_user(env->regwptr[UREG_I0 + i], &si->si_regs.u_regs[i+8]);
	}
	err |= __put_user(mask, &si->si_mask);
	return err;
}

#if 0
static int
setup_sigcontext(struct target_sigcontext *sc, /*struct _fpstate *fpstate,*/
		 CPUState *env, unsigned long mask)
{
	int err = 0;

	err |= __put_user(mask, &sc->sigc_mask);
	err |= __put_user(env->regwptr[UREG_SP], &sc->sigc_sp);
	err |= __put_user(env->pc, &sc->sigc_pc);
	err |= __put_user(env->npc, &sc->sigc_npc);
	err |= __put_user(env->psr, &sc->sigc_psr);
	err |= __put_user(env->gregs[1], &sc->sigc_g1);
	err |= __put_user(env->regwptr[UREG_O0], &sc->sigc_o0);

	return err;
}
#endif
#define NF_ALIGNEDSZ  (((sizeof(struct target_signal_frame) + 7) & (~7)))

static void setup_frame(int sig, struct emulated_sigaction *ka,
			target_sigset_t *set, CPUState *env)
{
	struct target_signal_frame *sf;
	int sigframe_size, err, i;

	/* 1. Make sure everything is clean */
	//synchronize_user_stack();

        sigframe_size = NF_ALIGNEDSZ;

	sf = (struct target_signal_frame *)
		get_sigframe(ka, env, sigframe_size);

	//fprintf(stderr, "sf: %x pc %x fp %x sp %x\n", sf, env->pc, env->regwptr[UREG_FP], env->regwptr[UREG_SP]);
#if 0
	if (invalid_frame_pointer(sf, sigframe_size))
		goto sigill_and_return;
#endif
	/* 2. Save the current process state */
	err = setup___siginfo(&sf->info, env, set->sig[0]);
	err |= __put_user(0, &sf->extra_size);

	//err |= save_fpu_state(regs, &sf->fpu_state);
	//err |= __put_user(&sf->fpu_state, &sf->fpu_save);

	err |= __put_user(set->sig[0], &sf->info.si_mask);
	for (i = 0; i < TARGET_NSIG_WORDS - 1; i++) {
		err |= __put_user(set->sig[i + 1], &sf->extramask[i]);
	}

	for (i = 0; i < 8; i++) {
	  	err |= __put_user(env->regwptr[i + UREG_L0], &sf->ss.locals[i]);
	}
	for (i = 0; i < 8; i++) {
	  	err |= __put_user(env->regwptr[i + UREG_I0], &sf->ss.ins[i]);
	}
	if (err)
		goto sigsegv;

	/* 3. signal handler back-trampoline and parameters */
	env->regwptr[UREG_FP] = h2g(sf);
	env->regwptr[UREG_I0] = sig;
	env->regwptr[UREG_I1] = h2g(&sf->info);
	env->regwptr[UREG_I2] = h2g(&sf->info);

	/* 4. signal handler */
	env->pc = (unsigned long) ka->sa._sa_handler;
	env->npc = (env->pc + 4);
	/* 5. return to kernel instructions */
	if (ka->sa.sa_restorer)
		env->regwptr[UREG_I7] = (unsigned long)ka->sa.sa_restorer;
	else {
		env->regwptr[UREG_I7] = h2g(&(sf->insns[0]) - 2);

		/* mov __NR_sigreturn, %g1 */
		err |= __put_user(0x821020d8, &sf->insns[0]);

		/* t 0x10 */
		err |= __put_user(0x91d02010, &sf->insns[1]);
		if (err)
			goto sigsegv;

		/* Flush instruction space. */
		//flush_sig_insns(current->mm, (unsigned long) &(sf->insns[0]));
                //		tb_flush(env);
	}
	return;

        //sigill_and_return:
	force_sig(TARGET_SIGILL);
sigsegv:
	//fprintf(stderr, "force_sig\n");
	force_sig(TARGET_SIGSEGV);
}
static inline int
restore_fpu_state(CPUState *env, qemu_siginfo_fpu_t *fpu)
{
        int err;
#if 0
#ifdef CONFIG_SMP
        if (current->flags & PF_USEDFPU)
                regs->psr &= ~PSR_EF;
#else
        if (current == last_task_used_math) {
                last_task_used_math = 0;
                regs->psr &= ~PSR_EF;
        }
#endif
        current->used_math = 1;
        current->flags &= ~PF_USEDFPU;
#endif
#if 0
        if (verify_area (VERIFY_READ, fpu, sizeof(*fpu)))
                return -EFAULT;
#endif

#if 0
        /* XXX: incorrect */
        err = __copy_from_user(&env->fpr[0], &fpu->si_float_regs[0],
	                             (sizeof(unsigned long) * 32));
#endif
        err |= __get_user(env->fsr, &fpu->si_fsr);
#if 0
        err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
        if (current->thread.fpqdepth != 0)
                err |= __copy_from_user(&current->thread.fpqueue[0],
                                        &fpu->si_fpqueue[0],
                                        ((sizeof(unsigned long) +
                                        (sizeof(unsigned long *)))*16));
#endif
        return err;
}


static void setup_rt_frame(int sig, struct emulated_sigaction *ka, 
                           target_siginfo_t *info,
			   target_sigset_t *set, CPUState *env)
{
    fprintf(stderr, "setup_rt_frame: not implemented\n");
}

long do_sigreturn(CPUState *env)
{
        struct target_signal_frame *sf;
        uint32_t up_psr, pc, npc;
        target_sigset_t set;
        sigset_t host_set;