signal.c

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	struct target_xmmreg	_xmm[8];
	target_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;
	target_ulong edi;
	target_ulong esi;
	target_ulong ebp;
	target_ulong esp;
	target_ulong ebx;
	target_ulong edx;
	target_ulong ecx;
	target_ulong eax;
	target_ulong trapno;
	target_ulong err;
	target_ulong eip;
	uint16_t cs, __csh;
	target_ulong eflags;
	target_ulong esp_at_signal;
	uint16_t ss, __ssh;
        target_ulong fpstate; /* pointer */
	target_ulong oldmask;
	target_ulong cr2;
};

typedef struct target_sigaltstack {
	target_ulong ss_sp;
	int ss_flags;
	target_ulong ss_size;
} target_stack_t;

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

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

struct rt_sigframe
{
    target_ulong pretcode;
    int sig;
    target_ulong pinfo;
    target_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, unsigned long mask)
{
	int err = 0;

	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, (void *)fpstate, 1);
        fpstate->status = fpstate->sw;
        err |= __put_user(0xffff, &fpstate->magic);
        err |= __put_user(fpstate, &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 void *
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];
#if 0
	/* This is the X/Open sanctioned signal stack switching.  */
	if (ka->sa.sa_flags & SA_ONSTACK) {
		if (sas_ss_flags(esp) == 0)
			esp = current->sas_ss_sp + current->sas_ss_size;
	}

	/* This is the legacy signal stack switching. */
	else 
#endif
        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 g2h((esp - frame_size) & -8ul);
}

static void setup_frame(int sig, struct emulated_sigaction *ka,
			target_sigset_t *set, CPUX86State *env)
{
	struct sigframe *frame;
	int i, err = 0;

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;
	err |= __put_user((/*current->exec_domain
		           && current->exec_domain->signal_invmap
		           && sig < 32
		           ? current->exec_domain->signal_invmap[sig]
		           : */ sig),
		          &frame->sig);
	if (err)
		goto give_sigsegv;

	setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0]);
	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 {
		err |= __put_user(frame->retcode, &frame->pretcode);
		/* This is popl %eax ; movl $,%eax ; int $0x80 */
		err |= __put_user(0xb858, (short *)(frame->retcode+0));
		err |= __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2));
		err |= __put_user(0x80cd, (short *)(frame->retcode+6));
	}

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	env->regs[R_ESP] = h2g(frame);
	env->eip = (unsigned long) 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;

	return;

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

static void setup_rt_frame(int sig, struct emulated_sigaction *ka, 
                           target_siginfo_t *info,
			   target_sigset_t *set, CPUX86State *env)
{
	struct rt_sigframe *frame;
	int i, err = 0;

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

	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
		goto give_sigsegv;

	err |= __put_user((/*current->exec_domain
		    	   && current->exec_domain->signal_invmap
		    	   && sig < 32
		    	   ? current->exec_domain->signal_invmap[sig]
			   : */sig),
			  &frame->sig);
	err |= __put_user((target_ulong)&frame->info, &frame->pinfo);
	err |= __put_user((target_ulong)&frame->uc, &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(/*current->sas_ss_sp*/ 0,
			  &frame->uc.tuc_stack.ss_sp);
	err |= __put_user(/* sas_ss_flags(regs->esp) */ 0,
			  &frame->uc.tuc_stack.ss_flags);
	err |= __put_user(/* current->sas_ss_size */ 0,
			  &frame->uc.tuc_stack.ss_size);
	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]))
                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 {
		err |= __put_user(frame->retcode, &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));
		err |= __put_user(0x80cd, (short *)(frame->retcode+5));
	}

	if (err)
		goto give_sigsegv;

	/* Set up registers for signal handler */
	env->regs[R_ESP] = (unsigned long) frame;
	env->eip = (unsigned long) 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;

	return;

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

static int
restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc, int *peax)
{
	unsigned int err = 0;

        cpu_x86_load_seg(env, R_GS, lduw(&sc->gs));
        cpu_x86_load_seg(env, R_FS, lduw(&sc->fs));
        cpu_x86_load_seg(env, R_ES, lduw(&sc->es));
        cpu_x86_load_seg(env, R_DS, lduw(&sc->ds));

        env->regs[R_EDI] = ldl(&sc->edi);
        env->regs[R_ESI] = ldl(&sc->esi);
        env->regs[R_EBP] = ldl(&sc->ebp);
        env->regs[R_ESP] = ldl(&sc->esp);
        env->regs[R_EBX] = ldl(&sc->ebx);
        env->regs[R_EDX] = ldl(&sc->edx);
        env->regs[R_ECX] = ldl(&sc->ecx);
        env->eip = ldl(&sc->eip);

        cpu_x86_load_seg(env, R_CS, lduw(&sc->cs) | 3);
        cpu_x86_load_seg(env, R_SS, lduw(&sc->ss) | 3);
	
	{
		unsigned int tmpflags;
                tmpflags = ldl(&sc->eflags);
		env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
                //		regs->orig_eax = -1;		/* disable syscall checks */
	}

	{
		struct _fpstate * buf;
                buf = (void *)ldl(&sc->fpstate);
		if (buf) {
#if 0
			if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
				goto badframe;
#endif
                        cpu_x86_frstor(env, (void *)buf, 1);
		}
	}

        *peax = ldl(&sc->eax);
	return err;
#if 0
badframe:
	return 1;
#endif
}

long do_sigreturn(CPUX86State *env)
{
    struct sigframe *frame = (struct sigframe *)g2h(env->regs[R_ESP] - 8);
    target_sigset_t target_set;
    sigset_t set;
    int eax, i;

#if defined(DEBUG_SIGNAL)
    fprintf(stderr, "do_sigreturn\n");
#endif
    /* set blocked signals */
    if (__get_user(target_set.sig[0], &frame->sc.oldmask))
        goto badframe;
    for(i = 1; i < TARGET_NSIG_WORDS; i++) {
        if (__get_user(target_set.sig[i], &frame->extramask[i - 1]))
            goto badframe;
    }

    target_to_host_sigset_internal(&set, &target_set);
    sigprocmask(SIG_SETMASK, &set, NULL);
    
    /* restore registers */
    if (restore_sigcontext(env, &frame->sc, &eax))
        goto badframe;
    return eax;

badframe:
    force_sig(TARGET_SIGSEGV);
    return 0;
}

long do_rt_sigreturn(CPUX86State *env)
{
	struct rt_sigframe *frame = (struct rt_sigframe *)g2h(env->regs[R_ESP] - 4);
        sigset_t set;
        //	stack_t st;
	int eax;

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

#if 0
	if (__copy_from_user(&st, &frame->uc.tuc_stack, sizeof(st)))
		goto badframe;
	/* It is more difficult to avoid calling this function than to
	   call it and ignore errors.  */
	do_sigaltstack(&st, NULL, regs->esp);
#endif
	return eax;

badframe:
	force_sig(TARGET_SIGSEGV);
	return 0;
}

#elif defined(TARGET_ARM)

struct target_sigcontext {
	target_ulong trap_no;
	target_ulong error_code;
	target_ulong oldmask;
	target_ulong arm_r0;
	target_ulong arm_r1;
	target_ulong arm_r2;
	target_ulong arm_r3;
	target_ulong arm_r4;
	target_ulong arm_r5;
	target_ulong arm_r6;
	target_ulong arm_r7;
	target_ulong arm_r8;
	target_ulong arm_r9;
	target_ulong arm_r10;
	target_ulong arm_fp;
	target_ulong arm_ip;
	target_ulong arm_sp;
	target_ulong arm_lr;
	target_ulong arm_pc;
	target_ulong arm_cpsr;
	target_ulong fault_address;
};

typedef struct target_sigaltstack {
	target_ulong ss_sp;
	int ss_flags;
	target_ulong ss_size;
} target_stack_t;

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

struct sigframe
{
    struct target_sigcontext sc;
    target_ulong extramask[TARGET_NSIG_WORDS-1];
    target_ulong retcode;
};

struct rt_sigframe
{
    struct target_siginfo *pinfo;
    void *puc;
    struct target_siginfo info;
    struct target_ucontext uc;
    target_ulong retcode;
};

#define TARGET_CONFIG_CPU_32 1

/*
 * For ARM syscalls, we encode the syscall number into the instruction.
 */
#define SWI_SYS_SIGRETURN	(0xef000000|(TARGET_NR_sigreturn + ARM_SYSCALL_BASE))
#define SWI_SYS_RT_SIGRETURN	(0xef000000|(TARGET_NR_rt_sigreturn + ARM_SYSCALL_BASE))

/*
 * For Thumb syscalls, we pass the syscall number via r7.  We therefore
 * need two 16-bit instructions.
 */
#define SWI_THUMB_SIGRETURN	(0xdf00 << 16 | 0x2700 | (TARGET_NR_sigreturn))
#define SWI_THUMB_RT_SIGRETURN	(0xdf00 << 16 | 0x2700 | (TARGET_NR_rt_sigreturn))

static const target_ulong retcodes[4] = {
	SWI_SYS_SIGRETURN,	SWI_THUMB_SIGRETURN,
	SWI_SYS_RT_SIGRETURN,	SWI_THUMB_RT_SIGRETURN
};


#define __put_user_error(x,p,e) __put_user(x, p)
#define __get_user_error(x,p,e) __get_user(x, p)

static inline int valid_user_regs(CPUState *regs)
{
    return 1;
}

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

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

	__put_user_error(/* current->thread.trap_no */ 0, &sc->trap_no, err);
	__put_user_error(/* current->thread.error_code */ 0, &sc->error_code, err);
	__put_user_error(/* current->thread.address */ 0, &sc->fault_address, err);
	__put_user_error(mask, &sc->oldmask, err);

	return err;
}

static inline void *
get_sigframe(struct emulated_sigaction *ka, CPUState *regs, int framesize)
{
	unsigned long sp = regs->regs[13];

#if 0
	/*
	 * This is the X/Open sanctioned signal stack switching.
	 */
	if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
		sp = current->sas_ss_sp + current->sas_ss_size;
#endif
	/*
	 * ATPCS B01 mandates 8-byte alignment
	 */
	return g2h((sp - framesize) & ~7);