basic signal handling

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@41 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 712 insertions, 27 deletions

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 2e0d599553..61baf995ae 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -1,5 +1,5 @@
 /*
- *  Emulation of Linux signal handling
+ *  Emulation of Linux signals
  * 
  *  Copyright (c) 2003 Fabrice Bellard
  *
@@ -19,22 +19,49 @@
  */
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 #include <stdarg.h>
 #include <signal.h>
+#include <errno.h>
 #include <sys/ucontext.h>
 
-/* Algorithm strongly inspired from em86 : we queue the signals so
-   that we can handle them at precise points in the emulated code. */
+#include "gemu.h"
+
+#include "syscall_defs.h"
+
+#ifdef TARGET_I386
+#include "cpu-i386.h"
+#include "syscall-i386.h"
+#endif
+
+/* signal handling inspired from em86. */
+
+//#define DEBUG_SIGNAL
+
+#define MAX_SIGQUEUE_SIZE 1024
+
+struct sigqueue {
+    struct sigqueue *next;
+    siginfo_t info;
+};
 
 struct emulated_sigaction {
     struct target_sigaction sa;
-    int nb_pending;
-    struct target_siginfo info;
+    int pending; /* true if signal is pending */
+    struct sigqueue *first;
+    struct sigqueue info; /* in order to always have memory for the
+                             first signal, we put it here */
 };
 
-struct emulated_sigaction sigact_table[NSIG];
-int signal_pending;
+static struct emulated_sigaction sigact_table[TARGET_NSIG];
+static struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */
+static struct sigqueue *first_free; /* first free siginfo queue entry */
+static int signal_pending; /* non zero if a signal may be pending */
 
+static void host_signal_handler(int host_signum, siginfo_t *info, 
+                                void *puc);
+
+/* XXX: do it properly */
 static inline int host_to_target_signal(int sig)
 {
     return sig;
@@ -45,6 +72,51 @@ static inline int target_to_host_signal(int sig)
     return sig;
 }
 
+void host_to_target_sigset(target_sigset_t *d, sigset_t *s)
+{
+    int i;
+    for(i = 0;i < TARGET_NSIG_WORDS; i++) {
+        d->sig[i] = tswapl(((unsigned long *)s)[i]);
+    }
+}
+
+void target_to_host_sigset(sigset_t *d, target_sigset_t *s)
+{
+    int i;
+    for(i = 0;i < TARGET_NSIG_WORDS; i++) {
+        ((unsigned long *)d)[i] = tswapl(s->sig[i]);
+    }
+}
+
+void host_to_target_old_sigset(target_ulong *old_sigset, 
+                               const sigset_t *sigset)
+{
+    *old_sigset = tswap32(*(unsigned long *)sigset & 0xffffffff);
+}
+
+void target_to_host_old_sigset(sigset_t *sigset, 
+                               const target_ulong *old_sigset)
+{
+    sigemptyset(sigset);
+    *(unsigned long *)sigset = tswapl(*old_sigset);
+}
+
+/* XXX: finish it */
+void host_to_target_siginfo(target_siginfo_t *tinfo, siginfo_t *info)
+{
+    tinfo->si_signo = tswap32(info->si_signo);
+    tinfo->si_errno = tswap32(info->si_errno);
+    tinfo->si_code = tswap32(info->si_code);
+}
+
+/* XXX: finish it */
+void target_to_host_siginfo(siginfo_t *info, target_siginfo_t *tinfo)
+{
+    info->si_signo = tswap32(tinfo->si_signo);
+    info->si_errno = tswap32(tinfo->si_errno);
+    info->si_code = tswap32(tinfo->si_code);
+}
+
 void signal_init(void)
 {
     struct sigaction act;
@@ -55,51 +127,664 @@ void signal_init(void)
     act.sa_flags = SA_SIGINFO;
     act.sa_sigaction = host_signal_handler;
     for(i = 1; i < NSIG; i++) {
-	sigaction(i, &sa, NULL);
+	sigaction(i, &act, NULL);
     }
     
     memset(sigact_table, 0, sizeof(sigact_table));
+
+    first_free = &sigqueue_table[0];
+    for(i = 0; i < MAX_SIGQUEUE_SIZE - 1; i++) 
+        sigqueue_table[i].next = &sigqueue_table[i + 1];
+    sigqueue_table[MAX_SIGQUEUE_SIZE - 1].next = NULL;
+}
+
+/* signal queue handling */
+
+static inline struct sigqueue *alloc_sigqueue(void)
+{
+    struct sigqueue *q = first_free;
+    if (!q)
+        return NULL;
+    first_free = q->next;
+    return q;
 }
 
+static inline void free_sigqueue(struct sigqueue *q)
+{
+    q->next = first_free;
+    first_free = q;
+}
+
+static int queue_signal(struct emulated_sigaction *k, int sig, siginfo_t *info)
+{
+    struct sigqueue *q, **pq;
+
+    pq = &k->first;
+    if (!k->pending || sig < TARGET_SIGRTMIN) {
+        /* first signal or non real time signal */
+        q = &k->info;
+    } else {
+        q = alloc_sigqueue();
+        if (!q)
+            return -EAGAIN;
+        while (*pq != NULL)
+            pq = &(*pq)->next;
+    }
+    *pq = q;
+    q->info = *info;
+    q->next = NULL;
+    k->pending = 1;
+    /* signal that a new signal is pending */
+    signal_pending = 1;
+    return 0;
+}
+
+void force_sig(int sig)
+{
+    int host_sig;
+    /* abort execution with signal */
+    host_sig = target_to_host_signal(sig);
+    fprintf(stderr, "gemu: uncaught target signal %d (%s) - exiting\n", 
+            sig, strsignal(host_sig));
+    _exit(-host_sig);
+}
+
+
 static void host_signal_handler(int host_signum, siginfo_t *info, 
                                 void *puc)
 {
-    struct ucontext *uc = puc;
-    int signum;
+    struct emulated_sigaction *k;
+    int sig;
+    target_ulong handler;
+
     /* get target signal number */
-    signum = host_to_target(host_signum);
-    if (signum >= TARGET_NSIG)
+    sig = host_to_target_signal(host_signum);
+    if (sig < 1 || sig > TARGET_NSIG)
         return;
-    /* we save the old mask */
-    
-    
+    k = &sigact_table[sig - 1];
+#ifdef DEBUG_SIGNAL
+    fprintf(stderr, "gemu: got signal %d\n", sig);
+#endif
+    handler = k->sa._sa_handler;
+    if (handler == TARGET_SIG_DFL) {
+        /* default handler : ignore some signal. The other are fatal */
+        if (sig != TARGET_SIGCHLD && 
+            sig != TARGET_SIGURG && 
+            sig != TARGET_SIGWINCH) {
+            force_sig(sig);
+        }
+    } else if (handler == TARGET_SIG_IGN) {
+        /* ignore signal */
+    } else if (handler == TARGET_SIG_ERR) {
+        force_sig(sig);
+    } else {
+        queue_signal(k, sig, info);
+    }
+}
+
+int do_sigaction(int sig, const struct target_sigaction *act,
+                 struct target_sigaction *oact)
+{
+    struct emulated_sigaction *k;
+
+    if (sig < 1 || sig > TARGET_NSIG)
+        return -EINVAL;
+    k = &sigact_table[sig - 1];
+#if defined(DEBUG_SIGNAL) && 0
+    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);
+        oact->sa_restorer = tswapl(k->sa.sa_restorer);
+        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);
+        k->sa.sa_restorer = tswapl(act->sa_restorer);
+        k->sa.sa_mask = act->sa_mask;
+    }
+    return 0;
+}
+
+#ifdef TARGET_I386
+
+/* 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 {
+	target_ulong element[4];
+};
+
+struct target_fpstate {
+	/* Regular FPU environment */
+	target_ulong 	cw;
+	target_ulong	sw;
+	target_ulong	tag;
+	target_ulong	ipoff;
+	target_ulong	cssel;
+	target_ulong	dataoff;
+	target_ulong	datasel;
+	struct target_fpreg	_st[8];
+	uint16_t	status;
+	uint16_t	magic;		/* 0xffff = regular FPU data only */
+
+	/* FXSR FPU environment */
+	target_ulong	_fxsr_env[6];	/* FXSR FPU env is ignored */
+	target_ulong	mxcsr;
+	target_ulong	reserved;
+	struct target_fpxreg	_fxsr_st[8];	/* FXSR FPU reg data is ignored */
+	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	  uc_flags;
+	target_ulong      uc_link;
+	target_stack_t	  uc_stack;
+	struct target_sigcontext uc_mcontext;
+	target_sigset_t	  uc_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.
+ */
+
+#define __put_user(x,ptr)\
+({\
+    int size = sizeof(*ptr);\
+    switch(size) {\
+    case 1:\
+        stb(ptr, (typeof(*ptr))(x));\
+        break;\
+    case 2:\
+        stw(ptr, (typeof(*ptr))(x));\
+        break;\
+    case 4:\
+        stl(ptr, (typeof(*ptr))(x));\
+        break;\
+    case 8:\
+        stq(ptr, (typeof(*ptr))(x));\
+        break;\
+    default:\
+        abort();\
+    }\
+    0;\
+})
+
+#define get_user(val, ptr) (typeof(*ptr))(*(ptr))
+
+
+#define __copy_to_user(dst, src, size)\
+({\
+    memcpy(dst, src, size);\
+    0;\
+})
+
+static inline int copy_siginfo_to_user(target_siginfo_t *tinfo, siginfo_t *info)
+{
+    host_to_target_siginfo(tinfo, info);
+    return 0;
+}
+
+/* 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], (unsigned int *)&sc->gs);
+	err |= __put_user(env->segs[R_FS], (unsigned int *)&sc->fs);
+	err |= __put_user(env->segs[R_ES], (unsigned int *)&sc->es);
+	err |= __put_user(env->segs[R_DS], (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(/*current->thread.trap_no*/ 0, &sc->trapno);
+	err |= __put_user(/*current->thread.error_code*/ 0, &sc->err);
+	err |= __put_user(env->eip, &sc->eip);
+	err |= __put_user(env->segs[R_CS], (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], (unsigned int *)&sc->ss);
+#if 0
+	tmp = save_i387(fpstate);
+	if (tmp < 0)
+	  err = 1;
+	else
+	  err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
+#else
+        err |= __put_user(0, &sc->fpstate);
+#endif
+	/* non-iBCS2 extensions.. */
+	err |= __put_user(mask, &sc->oldmask);
+	err |= __put_user(/*current->thread.cr2*/ 0, &sc->cr2);
+
+	return err;
 }
 
+/*
+ * Determine which stack to use..
+ */
 
-void process_pending_signals(void)
+static inline void *
+get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size)
 {
-    int signum;
-    target_ulong _sa_handler;
+	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 if ((regs->xss & 0xffff) != __USER_DS &&
+		 !(ka->sa.sa_flags & SA_RESTORER) &&
+		 ka->sa.sa_restorer) {
+		esp = (unsigned long) ka->sa.sa_restorer;
+	}
+#endif
+	return (void *)((esp - frame_size) & -8ul);
+}
+
+#define TF_MASK TRAP_FLAG
+
+static void setup_frame(int sig, struct emulated_sigaction *ka,
+			target_sigset_t *set, CPUX86State *env)
+{
+	struct sigframe *frame;
+	int err = 0;
+
+	frame = get_sigframe(ka, env, sizeof(*frame));
+
+#if 0
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+#endif
+	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;
+
+	if (TARGET_NSIG_WORDS > 1) {
+		err |= __copy_to_user(frame->extramask, &set->sig[1],
+				      sizeof(frame->extramask));
+	}
+	if (err)
+		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] = (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 void setup_rt_frame(int sig, struct emulated_sigaction *ka, siginfo_t *info,
+			   target_sigset_t *set, CPUX86State *env)
+{
+	struct rt_sigframe *frame;
+	int err = 0;
+
+	frame = get_sigframe(ka, env, sizeof(*frame));
+
+#if 0
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
+#endif
+
+	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;
 
-    struct emulated_sigaction *esig;
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |= __put_user(/*current->sas_ss_sp*/ 0, &frame->uc.uc_stack.ss_sp);
+	err |= __put_user(/* sas_ss_flags(regs->esp) */ 0,
+			  &frame->uc.uc_stack.ss_flags);
+	err |= __put_user(/* current->sas_ss_size */ 0, &frame->uc.uc_stack.ss_size);
+	err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+			        env, set->sig[0]);
+	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+	if (err)
+		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;
+
+
+        
+#define COPY(x)		err |= __get_user(regs->x, &sc->x)
+
+#define COPY_SEG(seg)							\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  regs->x##seg = tmp; }
+
+#define COPY_SEG_STRICT(seg)						\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  regs->x##seg = tmp|3; }
+
+#define GET_SEG(seg)							\
+	{ unsigned short tmp;						\
+	  err |= __get_user(tmp, &sc->seg);				\
+	  loadsegment(seg,tmp); }
+
+        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 */
+	}
+
+#if 0
+	{
+		struct _fpstate * buf;
+		err |= __get_user(buf, &sc->fpstate);
+		if (buf) {
+			if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
+				goto badframe;
+			err |= restore_i387(buf);
+		}
+	}
+#endif
+        *peax = ldl(&sc->eax);
+	return err;
+#if 0
+badframe:
+	return 1;
+#endif
+}
+
+long do_sigreturn(CPUX86State *env)
+{
+    struct sigframe *frame = (struct sigframe *)(env->regs[R_ESP] - 8);
+    target_sigset_t target_set;
+    sigset_t set;
+    int eax, i;
+
+    /* set blocked signals */
+    target_set.sig[0] = frame->sc.oldmask;
+    for(i = 1; i < TARGET_NSIG_WORDS; i++)
+        target_set.sig[i] = frame->extramask[i - 1];
+
+    target_to_host_sigset(&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 *)(env->regs[R_ESP] - 4);
+	target_sigset_t target_set;
+        sigset_t set;
+        //	stack_t st;
+	int eax;
+
+#if 0
+	if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
+		goto badframe;
+#endif
+        memcpy(&target_set, &frame->uc.uc_sigmask, sizeof(target_sigset_t));
+
+        target_to_host_sigset(&set, &target_set);
+        sigprocmask(SIG_SETMASK, &set, NULL);
+	
+	if (restore_sigcontext(env, &frame->uc.uc_mcontext, &eax))
+		goto badframe;
+
+#if 0
+	if (__copy_from_user(&st, &frame->uc.uc_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;
+}
+
+#endif
+
+void process_pending_signals(void *cpu_env)
+{
+    int sig;
+    target_ulong handler;
+    target_sigset_t set;
+    struct emulated_sigaction *k;
+    struct sigqueue *q;
+    
     if (!signal_pending)
         return;
 
-    esig = sigact_table;
-    for(signum = 1; signum < TARGET_NSIG; signum++) {
-        if (esig->nb_pending != 0)
+    k = sigact_table;
+    for(sig = 1; sig <= TARGET_NSIG; sig++) {
+        if (k->pending)
             goto handle_signal;
-        esig++;
+        k++;
     }
     /* if no signal is pending, just return */
     signal_pending = 0;
     return;
+
  handle_signal:
-    _sa_handler = esig->sa._sa_handler;
-    if (_sa_handler == TARGET_SIG_DFL) {
-        /* default handling
+#ifdef DEBUG_SIGNAL
+    fprintf(stderr, "gemu: process signal %d\n", sig);
+#endif
+    /* dequeue signal */
+    q = k->first;
+    k->first = q->next;
+    if (!k->first)
+        k->pending = 0;
+
+    handler = k->sa._sa_handler;
+    if (handler == TARGET_SIG_DFL) {
+        /* default handler : ignore some signal. The other are fatal */
+        if (sig != TARGET_SIGCHLD && 
+            sig != TARGET_SIGURG && 
+            sig != TARGET_SIGWINCH) {
+            force_sig(sig);
+        }
+    } else if (handler == TARGET_SIG_IGN) {
+        /* ignore sig */
+    } else if (handler == TARGET_SIG_ERR) {
+        force_sig(sig);
+    } else {
+        set = k->sa.sa_mask;
+        /* send the signal to the CPU */
+        if (k->sa.sa_flags & TARGET_SA_SIGINFO)
+            setup_rt_frame(sig, k, &q->info, &set, cpu_env);
+        else
+            setup_frame(sig, k, &set, cpu_env);
+	if (k->sa.sa_flags & TARGET_SA_RESETHAND)
+            k->sa._sa_handler = TARGET_SIG_DFL;
     }
+    if (q != &k->info)
+        free_sigqueue(q);
+}
 
 
-}