text: /*
   * i386 signal handling routines
   *
   * Copyright 1999 Alexandre Julliard
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
   */
  
  #ifdef __i386__
  
  #include "config.h"
  #include "wine/port.h"
  
  #include <errno.h>
  #include <signal.h>
  #include <stdlib.h>
  #include <stdarg.h>
  #include <stdio.h>
  #include <sys/types.h>
  #ifdef HAVE_UNISTD_H
  # include <unistd.h>
  #endif
  #ifdef HAVE_SYS_PARAM_H
  # include <sys/param.h>
  #endif
  #ifdef HAVE_SYSCALL_H
  # include <syscall.h>
  #else
  # ifdef HAVE_SYS_SYSCALL_H
  #  include <sys/syscall.h>
  # endif
  #endif
  #ifdef HAVE_SYS_VM86_H
  # include <sys/vm86.h>
  #endif
  #ifdef HAVE_SYS_SIGNAL_H
  # include <sys/signal.h>
  #endif
  #ifdef HAVE_SYS_SYSCTL_H
  # include <sys/sysctl.h>
  #endif
  #ifdef HAVE_SYS_UCONTEXT_H
  # include <sys/ucontext.h>
  #endif
  
  #include "ntstatus.h"
  #define WIN32_NO_STATUS
  #include "windef.h"
  #include "wine/library.h"
  #include "ntdll_misc.h"
  #include "wine/exception.h"
  #include "wine/debug.h"
  
  #ifdef HAVE_VALGRIND_MEMCHECK_H
  #include <valgrind/memcheck.h>
  #endif
  
  #undef ERR  /* Solaris needs to define this */
  
  WINE_DEFAULT_DEBUG_CHANNEL(seh);
  WINE_DECLARE_DEBUG_CHANNEL(relay);
  
  /* not defined for x86, so copy the x86_64 definition */
  typedef struct DECLSPEC_ALIGN(16) _M128A
  {
      ULONGLONG Low;
      LONGLONG High;
  } M128A;
  
  typedef struct
  {
      WORD ControlWord;
      WORD StatusWord;
      BYTE TagWord;
      BYTE Reserved1;
      WORD ErrorOpcode;
      DWORD ErrorOffset;
      WORD ErrorSelector;
      WORD Reserved2;
      DWORD DataOffset;
      WORD DataSelector;
      WORD Reserved3;
      DWORD MxCsr;
      DWORD MxCsr_Mask;
      M128A FloatRegisters[8];
      M128A XmmRegisters[16];
      BYTE Reserved4[96];
  } XMM_SAVE_AREA32;
  
  /***********************************************************************
   * signal context platform-specific definitions
   */
  
  #ifdef __linux__
  
  #ifndef HAVE_SYS_UCONTEXT_H
  
  enum
  {
      REG_GS, REG_FS, REG_ES, REG_DS, REG_EDI, REG_ESI, REG_EBP, REG_ESP,
      REG_EBX, REG_EDX, REG_ECX, REG_EAX, REG_TRAPNO, REG_ERR, REG_EIP,
      REG_CS, REG_EFL, REG_UESP, REG_SS, NGREG
  };
  
  typedef int greg_t;
  typedef greg_t gregset_t[NGREG];
  
  struct _libc_fpreg
  {
      unsigned short significand[4];
      unsigned short exponent;
  };
  
  struct _libc_fpstate
  {
      unsigned long cw;
      unsigned long sw;
      unsigned long tag;
      unsigned long ipoff;
      unsigned long cssel;
      unsigned long dataoff;
      unsigned long datasel;
      struct _libc_fpreg _st[8];
      unsigned long status;
  };
  
  typedef struct _libc_fpstate* fpregset_t;
  
  typedef struct
  {
      gregset_t     gregs;
      fpregset_t    fpregs;
      unsigned long oldmask;
      unsigned long cr2;
  } mcontext_t;
  
  typedef struct ucontext
  {
      unsigned long     uc_flags;
      struct ucontext  *uc_link;
      stack_t           uc_stack;
      mcontext_t        uc_mcontext;
      sigset_t          uc_sigmask;
  } ucontext_t;
  #endif /* HAVE_SYS_UCONTEXT_H */
  
  #define EAX_sig(context)     ((context)->uc_mcontext.gregs[REG_EAX])
  #define EBX_sig(context)     ((context)->uc_mcontext.gregs[REG_EBX])
  #define ECX_sig(context)     ((context)->uc_mcontext.gregs[REG_ECX])
  #define EDX_sig(context)     ((context)->uc_mcontext.gregs[REG_EDX])
  #define ESI_sig(context)     ((context)->uc_mcontext.gregs[REG_ESI])
  #define EDI_sig(context)     ((context)->uc_mcontext.gregs[REG_EDI])
  #define EBP_sig(context)     ((context)->uc_mcontext.gregs[REG_EBP])
  #define ESP_sig(context)     ((context)->uc_mcontext.gregs[REG_ESP])
  
  #define CS_sig(context)      ((context)->uc_mcontext.gregs[REG_CS])
  #define DS_sig(context)      ((context)->uc_mcontext.gregs[REG_DS])
  #define ES_sig(context)      ((context)->uc_mcontext.gregs[REG_ES])
  #define SS_sig(context)      ((context)->uc_mcontext.gregs[REG_SS])
  #define FS_sig(context)      ((context)->uc_mcontext.gregs[REG_FS])
  #define GS_sig(context)      ((context)->uc_mcontext.gregs[REG_GS])
  
  #define EFL_sig(context)     ((context)->uc_mcontext.gregs[REG_EFL])
  #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
  #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
  #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
  
  #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->uc_mcontext.fpregs))
  #define FPUX_sig(context)    (FPU_sig(context) && !((context)->uc_mcontext.fpregs->status >> 16) ? (XMM_SAVE_AREA32 *)(FPU_sig(context) + 1) : NULL)
  
  #define VIF_FLAG 0x00080000
  #define VIP_FLAG 0x00100000
  
  int vm86_enter( void **vm86_ptr );
  void vm86_return(void);
  void vm86_return_end(void);
  __ASM_GLOBAL_FUNC(vm86_enter,
                    "pushl %ebp\n\t"
                    __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                    __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                    "movl %esp,%ebp\n\t"
                    __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                    "pushl %ebx\n\t"
                    __ASM_CFI(".cfi_rel_offset %ebx,-4\n\t")
                    "movl $166,%eax\n\t"  /*SYS_vm86*/
                    "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
                    "movl (%ecx),%ecx\n\t"
                    "movl $1,%ebx\n\t"    /*VM86_ENTER*/
                    "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
                    "pushl %fs\n\t"
                    "pushl %gs\n\t"
                    "int $0x80\n"
                    ".globl " __ASM_NAME("vm86_return") "\n\t"
                    __ASM_FUNC("vm86_return") "\n"
                    __ASM_NAME("vm86_return") ":\n\t"
                    "popl %gs\n\t"
                    "popl %fs\n\t"
                    "popl %ecx\n\t"
                    "popl %ebx\n\t"
                    __ASM_CFI(".cfi_same_value %ebx\n\t")
                    "popl %ebp\n\t"
                    __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                    __ASM_CFI(".cfi_same_value %ebp\n\t")
                    "testl %eax,%eax\n\t"
                    "jl 0f\n\t"
                    "cmpb $0,%al\n\t" /* VM86_SIGNAL */
                    "je " __ASM_NAME("vm86_enter") "\n\t"
                    "0:\n\t"
                    "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
                    "movl $0,(%ecx)\n\t"
                    ".globl " __ASM_NAME("vm86_return_end") "\n\t"
                    __ASM_FUNC("vm86_return_end") "\n"
                    __ASM_NAME("vm86_return_end") ":\n\t"
                    "ret" )
  
  #ifdef HAVE_SYS_VM86_H
  # define __HAVE_VM86
  #endif
  
  #ifdef __ANDROID__
  /* custom signal restorer since we may have unmapped the one in vdso, and bionic doesn't check for that */
  void rt_sigreturn(void);
  __ASM_GLOBAL_FUNC( rt_sigreturn,
                     "movl $173,%eax\n\t"  /* NR_rt_sigreturn */
                     "int $0x80" );
  #endif
  
  #elif defined (__BSDI__)
  
  #include <machine/frame.h>
  typedef struct trapframe ucontext_t;
  
  #define EAX_sig(context)     ((context)->tf_eax)
  #define EBX_sig(context)     ((context)->tf_ebx)
  #define ECX_sig(context)     ((context)->tf_ecx)
  #define EDX_sig(context)     ((context)->tf_edx)
  #define ESI_sig(context)     ((context)->tf_esi)
  #define EDI_sig(context)     ((context)->tf_edi)
  #define EBP_sig(context)     ((context)->tf_ebp)
  
  #define CS_sig(context)      ((context)->tf_cs)
  #define DS_sig(context)      ((context)->tf_ds)
  #define ES_sig(context)      ((context)->tf_es)
  #define SS_sig(context)      ((context)->tf_ss)
  
  #define EFL_sig(context)     ((context)->tf_eflags)
  
  #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
  #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
  
  #define FPU_sig(context)     NULL  /* FIXME */
  #define FPUX_sig(context)    NULL  /* FIXME */
  
  #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
  
  #include <machine/trap.h>
  
  #define EAX_sig(context)     ((context)->uc_mcontext.mc_eax)
  #define EBX_sig(context)     ((context)->uc_mcontext.mc_ebx)
  #define ECX_sig(context)     ((context)->uc_mcontext.mc_ecx)
  #define EDX_sig(context)     ((context)->uc_mcontext.mc_edx)
  #define ESI_sig(context)     ((context)->uc_mcontext.mc_esi)
  #define EDI_sig(context)     ((context)->uc_mcontext.mc_edi)
  #define EBP_sig(context)     ((context)->uc_mcontext.mc_ebp)
  
  #define CS_sig(context)      ((context)->uc_mcontext.mc_cs)
  #define DS_sig(context)      ((context)->uc_mcontext.mc_ds)
  #define ES_sig(context)      ((context)->uc_mcontext.mc_es)
  #define FS_sig(context)      ((context)->uc_mcontext.mc_fs)
  #define GS_sig(context)      ((context)->uc_mcontext.mc_gs)
  #define SS_sig(context)      ((context)->uc_mcontext.mc_ss)
  
  #define TRAP_sig(context)    ((context)->uc_mcontext.mc_trapno)
  #define ERROR_sig(context)   ((context)->uc_mcontext.mc_err)
  #define EFL_sig(context)     ((context)->uc_mcontext.mc_eflags)
  
  #define EIP_sig(context)     ((context)->uc_mcontext.mc_eip)
  #define ESP_sig(context)     ((context)->uc_mcontext.mc_esp)
  
  #define FPU_sig(context)     NULL  /* FIXME */
  #define FPUX_sig(context)    NULL  /* FIXME */
  
  #elif defined (__OpenBSD__)
  
  #define EAX_sig(context)     ((context)->sc_eax)
  #define EBX_sig(context)     ((context)->sc_ebx)
  #define ECX_sig(context)     ((context)->sc_ecx)
  #define EDX_sig(context)     ((context)->sc_edx)
  #define ESI_sig(context)     ((context)->sc_esi)
  #define EDI_sig(context)     ((context)->sc_edi)
  #define EBP_sig(context)     ((context)->sc_ebp)
  
  #define CS_sig(context)      ((context)->sc_cs)
  #define DS_sig(context)      ((context)->sc_ds)
  #define ES_sig(context)      ((context)->sc_es)
  #define FS_sig(context)      ((context)->sc_fs)
  #define GS_sig(context)      ((context)->sc_gs)
  #define SS_sig(context)      ((context)->sc_ss)
  
  #define TRAP_sig(context)    ((context)->sc_trapno)
  #define ERROR_sig(context)   ((context)->sc_err)
  #define EFL_sig(context)     ((context)->sc_eflags)
  
  #define EIP_sig(context)     ((context)->sc_eip)
  #define ESP_sig(context)     ((context)->sc_esp)
  
  #define FPU_sig(context)     NULL  /* FIXME */
  #define FPUX_sig(context)    NULL  /* FIXME */
  
  #define T_MCHK T_MACHK
  #define T_XMMFLT T_XFTRAP
  
  #elif defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
  
  #ifdef _SCO_DS
  #include <sys/regset.h>
  #define gregs regs
  #endif
  
  #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
  #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
  #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
  #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
  #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
  #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
  #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
  
  #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
  #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
  #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
  #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
  
  #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
  #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
  
  #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
  
  #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
  #ifdef UESP
  #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
  #elif defined(R_ESP)
  #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
  #else
  #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
  #endif
  #ifdef ERR
  #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[ERR])
  #endif
  #ifdef TRAPNO
  #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
  #endif
  
  #define FPU_sig(context)     NULL  /* FIXME */
  #define FPUX_sig(context)    NULL  /* FIXME */
  
  #elif defined (__APPLE__)
  
  /* work around silly renaming of struct members in OS X 10.5 */
  #if __DARWIN_UNIX03 && defined(_STRUCT_X86_EXCEPTION_STATE32)
  #define EAX_sig(context)     ((context)->uc_mcontext->__ss.__eax)
  #define EBX_sig(context)     ((context)->uc_mcontext->__ss.__ebx)
  #define ECX_sig(context)     ((context)->uc_mcontext->__ss.__ecx)
  #define EDX_sig(context)     ((context)->uc_mcontext->__ss.__edx)
  #define ESI_sig(context)     ((context)->uc_mcontext->__ss.__esi)
  #define EDI_sig(context)     ((context)->uc_mcontext->__ss.__edi)
  #define EBP_sig(context)     ((context)->uc_mcontext->__ss.__ebp)
  #define CS_sig(context)      ((context)->uc_mcontext->__ss.__cs)
  #define DS_sig(context)      ((context)->uc_mcontext->__ss.__ds)
  #define ES_sig(context)      ((context)->uc_mcontext->__ss.__es)
  #define FS_sig(context)      ((context)->uc_mcontext->__ss.__fs)
  #define GS_sig(context)      ((context)->uc_mcontext->__ss.__gs)
  #define SS_sig(context)      ((context)->uc_mcontext->__ss.__ss)
  #define EFL_sig(context)     ((context)->uc_mcontext->__ss.__eflags)
  #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__eip))
  #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__esp))
  #define TRAP_sig(context)    ((context)->uc_mcontext->__es.__trapno)
  #define ERROR_sig(context)   ((context)->uc_mcontext->__es.__err)
  #define FPU_sig(context)     NULL
  #define FPUX_sig(context)    ((XMM_SAVE_AREA32 *)&(context)->uc_mcontext->__fs.__fpu_fcw)
  #else
  #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
  #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
  #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
  #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
  #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
  #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
  #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
  #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
  #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
  #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
  #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
  #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
  #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
  #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
  #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
  #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
  #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
  #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
  #define FPU_sig(context)     NULL
  #define FPUX_sig(context)    ((XMM_SAVE_AREA32 *)&(context)->uc_mcontext->fs.fpu_fcw)
  #endif
  
  #elif defined(__NetBSD__)
  
  #define EAX_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EAX])
  #define EBX_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EBX])
  #define ECX_sig(context)       ((context)->uc_mcontext.__gregs[_REG_ECX])
  #define EDX_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EDX])
  #define ESI_sig(context)       ((context)->uc_mcontext.__gregs[_REG_ESI])
  #define EDI_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EDI])
  #define EBP_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EBP])
  #define ESP_sig(context)       _UC_MACHINE_SP(context)
  
  #define CS_sig(context)        ((context)->uc_mcontext.__gregs[_REG_CS])
  #define DS_sig(context)        ((context)->uc_mcontext.__gregs[_REG_DS])
  #define ES_sig(context)        ((context)->uc_mcontext.__gregs[_REG_ES])
  #define SS_sig(context)        ((context)->uc_mcontext.__gregs[_REG_SS])
  #define FS_sig(context)        ((context)->uc_mcontext.__gregs[_REG_FS])
  #define GS_sig(context)        ((context)->uc_mcontext.__gregs[_REG_GS])
  
  #define EFL_sig(context)       ((context)->uc_mcontext.__gregs[_REG_EFL])
  #define EIP_sig(context)       _UC_MACHINE_PC(context)
  #define TRAP_sig(context)      ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
  #define ERROR_sig(context)     ((context)->uc_mcontext.__gregs[_REG_ERR])
  
  #define FPU_sig(context)     NULL
  #define FPUX_sig(context)    ((XMM_SAVE_AREA32 *)&((context)->uc_mcontext.__fpregs))
  
  #define T_MCHK T_MCA
  #define T_XMMFLT T_XMM
  
  #elif defined(__GNU__)
  
  #define EAX_sig(context)     ((context)->uc_mcontext.gregs[REG_EAX])
  #define EBX_sig(context)     ((context)->uc_mcontext.gregs[REG_EBX])
  #define ECX_sig(context)     ((context)->uc_mcontext.gregs[REG_ECX])
  #define EDX_sig(context)     ((context)->uc_mcontext.gregs[REG_EDX])
  #define ESI_sig(context)     ((context)->uc_mcontext.gregs[REG_ESI])
  #define EDI_sig(context)     ((context)->uc_mcontext.gregs[REG_EDI])
  #define EBP_sig(context)     ((context)->uc_mcontext.gregs[REG_EBP])
  #define ESP_sig(context)     ((context)->uc_mcontext.gregs[REG_ESP])
  
  #define CS_sig(context)      ((context)->uc_mcontext.gregs[REG_CS])
  #define DS_sig(context)      ((context)->uc_mcontext.gregs[REG_DS])
  #define ES_sig(context)      ((context)->uc_mcontext.gregs[REG_ES])
  #define SS_sig(context)      ((context)->uc_mcontext.gregs[REG_SS])
  #define FS_sig(context)      ((context)->uc_mcontext.gregs[REG_FS])
  #define GS_sig(context)      ((context)->uc_mcontext.gregs[REG_GS])
  
  #define EFL_sig(context)     ((context)->uc_mcontext.gregs[REG_EFL])
  #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
  #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
  #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
  
  #define FPU_sig(context)     ((FLOATING_SAVE_AREA *)&(context)->uc_mcontext.fpregs.fp_reg_set.fpchip_state)
  #define FPUX_sig(context)    NULL
  
  #else
  #error You must define the signal context functions for your platform
  #endif /* linux */
  
  typedef int (*wine_signal_handler)(unsigned int sig);
  
  static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
  static size_t signal_stack_mask;
  static size_t signal_stack_size;
  
  static wine_signal_handler handlers[256];
  
  static BOOL fpux_support;  /* whether the CPU supports extended fpu context */
  
  enum i386_trap_code
  {
      TRAP_x86_UNKNOWN    = -1,  /* Unknown fault (TRAP_sig not defined) */
  #if defined(__FreeBSD__) || defined (__FreeBSD_kernel__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
      TRAP_x86_DIVIDE     = T_DIVIDE,     /* Division by zero exception */
      TRAP_x86_TRCTRAP    = T_TRCTRAP,    /* Single-step exception */
      TRAP_x86_NMI        = T_NMI,        /* NMI interrupt */
      TRAP_x86_BPTFLT     = T_BPTFLT,     /* Breakpoint exception */
      TRAP_x86_OFLOW      = T_OFLOW,      /* Overflow exception */
      TRAP_x86_BOUND      = T_BOUND,      /* Bound range exception */
      TRAP_x86_PRIVINFLT  = T_PRIVINFLT,  /* Invalid opcode exception */
      TRAP_x86_DNA        = T_DNA,        /* Device not available exception */
      TRAP_x86_DOUBLEFLT  = T_DOUBLEFLT,  /* Double fault exception */
      TRAP_x86_FPOPFLT    = T_FPOPFLT,    /* Coprocessor segment overrun */
      TRAP_x86_TSSFLT     = T_TSSFLT,     /* Invalid TSS exception */
      TRAP_x86_SEGNPFLT   = T_SEGNPFLT,   /* Segment not present exception */
      TRAP_x86_STKFLT     = T_STKFLT,     /* Stack fault */
      TRAP_x86_PROTFLT    = T_PROTFLT,    /* General protection fault */
      TRAP_x86_PAGEFLT    = T_PAGEFLT,    /* Page fault */
      TRAP_x86_ARITHTRAP  = T_ARITHTRAP,  /* Floating point exception */
      TRAP_x86_ALIGNFLT   = T_ALIGNFLT,   /* Alignment check exception */
      TRAP_x86_MCHK       = T_MCHK,       /* Machine check exception */
      TRAP_x86_CACHEFLT   = T_XMMFLT      /* Cache flush exception */
  #else
      TRAP_x86_DIVIDE     = 0,   /* Division by zero exception */
      TRAP_x86_TRCTRAP    = 1,   /* Single-step exception */
      TRAP_x86_NMI        = 2,   /* NMI interrupt */
      TRAP_x86_BPTFLT     = 3,   /* Breakpoint exception */
      TRAP_x86_OFLOW      = 4,   /* Overflow exception */
      TRAP_x86_BOUND      = 5,   /* Bound range exception */
      TRAP_x86_PRIVINFLT  = 6,   /* Invalid opcode exception */
      TRAP_x86_DNA        = 7,   /* Device not available exception */
      TRAP_x86_DOUBLEFLT  = 8,   /* Double fault exception */
      TRAP_x86_FPOPFLT    = 9,   /* Coprocessor segment overrun */
      TRAP_x86_TSSFLT     = 10,  /* Invalid TSS exception */
      TRAP_x86_SEGNPFLT   = 11,  /* Segment not present exception */
      TRAP_x86_STKFLT     = 12,  /* Stack fault */
      TRAP_x86_PROTFLT    = 13,  /* General protection fault */
      TRAP_x86_PAGEFLT    = 14,  /* Page fault */
      TRAP_x86_ARITHTRAP  = 16,  /* Floating point exception */
      TRAP_x86_ALIGNFLT   = 17,  /* Alignment check exception */
      TRAP_x86_MCHK       = 18,  /* Machine check exception */
      TRAP_x86_CACHEFLT   = 19   /* SIMD exception (via SIGFPE) if CPU is SSE capable
                                    otherwise Cache flush exception (via SIGSEV) */
  #endif
  };
  
  struct x86_thread_data
  {
      DWORD              fs;            /* 1d4 TEB selector */
      DWORD              gs;            /* 1d8 libc selector; update winebuild if you move this! */
      DWORD              dr0;           /* 1dc debug registers */
      DWORD              dr1;           /* 1e0 */
      DWORD              dr2;           /* 1e4 */
      DWORD              dr3;           /* 1e8 */
      DWORD              dr6;           /* 1ec */
      DWORD              dr7;           /* 1f0 */
      void              *exit_frame;    /* 1f4 exit frame pointer */
  #ifdef __HAVE_VM86
      void              *vm86_ptr;      /* 1f8 data for vm86 mode */
      WINE_VM86_TEB_INFO vm86;          /* 1fc vm86 private data */
  #endif
      /* the ntdll_thread_data structure follows here */
  };
  
  C_ASSERT( offsetof( TEB, SystemReserved2 ) + offsetof( struct x86_thread_data, gs ) == 0x1d8 );
  #ifdef __HAVE_VM86
  C_ASSERT( offsetof( TEB, SystemReserved2 ) + offsetof( struct x86_thread_data, vm86 ) ==
            offsetof( TEB, GdiTebBatch ) + offsetof( struct ntdll_thread_data, __vm86 ));
  #endif
  
  static inline struct x86_thread_data *x86_thread_data(void)
  {
      return (struct x86_thread_data *)NtCurrentTeb()->SystemReserved2;
  }
  
  /* Exception record for handling exceptions happening inside exception handlers */
  typedef struct
  {
      EXCEPTION_REGISTRATION_RECORD frame;
      EXCEPTION_REGISTRATION_RECORD *prevFrame;
  } EXC_NESTED_FRAME;
  
  extern DWORD EXC_CallHandler( EXCEPTION_RECORD *record, EXCEPTION_REGISTRATION_RECORD *frame,
                                CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher,
                                PEXCEPTION_HANDLER handler, PEXCEPTION_HANDLER nested_handler );
  
  /***********************************************************************
   *           dispatch_signal
   */
  static inline int dispatch_signal(unsigned int sig)
  {
      if (handlers[sig] == NULL) return 0;
      return handlers[sig](sig);
  }
  
  
  /***********************************************************************
   *           get_trap_code
   *
   * Get the trap code for a signal.
   */
  static inline enum i386_trap_code get_trap_code( const ucontext_t *sigcontext )
  {
  #ifdef TRAP_sig
      return TRAP_sig(sigcontext);
  #else
      return TRAP_x86_UNKNOWN;  /* unknown trap code */
  #endif
  }
  
  /***********************************************************************
   *           get_error_code
   *
   * Get the error code for a signal.
   */
  static inline WORD get_error_code( const ucontext_t *sigcontext )
  {
  #ifdef ERROR_sig
      return ERROR_sig(sigcontext);
  #else
      return 0;
  #endif
  }
  
  /***********************************************************************
   *           get_signal_stack
   *
   * Get the base of the signal stack for the current thread.
   */
  static inline void *get_signal_stack(void)
  {
      return (char *)NtCurrentTeb() + 4096;
  }
  
  
  /***********************************************************************
   *           get_current_teb
   *
   * Get the current teb based on the stack pointer.
   */
  static inline TEB *get_current_teb(void)
  {
      unsigned long esp;
      __asm__("movl %%esp,%0" : "=g" (esp) );
      return (TEB *)(esp & ~signal_stack_mask);
  }
  
  
  /*******************************************************************
   *         is_valid_frame
   */
  static inline BOOL is_valid_frame( void *frame )
  {
      if ((ULONG_PTR)frame & 3) return FALSE;
      return (frame >= NtCurrentTeb()->Tib.StackLimit &&
              (void **)frame < (void **)NtCurrentTeb()->Tib.StackBase - 1);
  }
  
  /*******************************************************************
   *         raise_handler
   *
   * Handler for exceptions happening inside a handler.
   */
  static DWORD raise_handler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
                              CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
  {
      if (rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND))
          return ExceptionContinueSearch;
      /* We shouldn't get here so we store faulty frame in dispatcher */
      *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
      return ExceptionNestedException;
  }
  
  
  /*******************************************************************
   *         unwind_handler
   *
   * Handler for exceptions happening inside an unwind handler.
   */
  static DWORD unwind_handler( EXCEPTION_RECORD *rec, EXCEPTION_REGISTRATION_RECORD *frame,
                               CONTEXT *context, EXCEPTION_REGISTRATION_RECORD **dispatcher )
  {
      if (!(rec->ExceptionFlags & (EH_UNWINDING | EH_EXIT_UNWIND)))
          return ExceptionContinueSearch;
      /* We shouldn't get here so we store faulty frame in dispatcher */
      *dispatcher = ((EXC_NESTED_FRAME*)frame)->prevFrame;
      return ExceptionCollidedUnwind;
  }
  
  
  /**********************************************************************
   *           call_stack_handlers
   *
   * Call the stack handlers chain.
   */
  static NTSTATUS call_stack_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      EXCEPTION_REGISTRATION_RECORD *frame, *dispatch, *nested_frame;
      DWORD res;
  
      frame = NtCurrentTeb()->Tib.ExceptionList;
      nested_frame = NULL;
      while (frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL)
      {
          /* Check frame address */
          if (!is_valid_frame( frame ))
          {
              rec->ExceptionFlags |= EH_STACK_INVALID;
              break;
          }
  
          /* Call handler */
          TRACE( "calling handler at %p code=%x flags=%x\n",
                 frame->Handler, rec->ExceptionCode, rec->ExceptionFlags );
          res = EXC_CallHandler( rec, frame, context, &dispatch, frame->Handler, raise_handler );
          TRACE( "handler at %p returned %x\n", frame->Handler, res );
  
          if (frame == nested_frame)
          {
              /* no longer nested */
              nested_frame = NULL;
              rec->ExceptionFlags &= ~EH_NESTED_CALL;
          }
  
          switch(res)
          {
          case ExceptionContinueExecution:
              if (!(rec->ExceptionFlags & EH_NONCONTINUABLE)) return STATUS_SUCCESS;
              return STATUS_NONCONTINUABLE_EXCEPTION;
          case ExceptionContinueSearch:
              break;
          case ExceptionNestedException:
              if (nested_frame < dispatch) nested_frame = dispatch;
              rec->ExceptionFlags |= EH_NESTED_CALL;
              break;
          default:
              return STATUS_INVALID_DISPOSITION;
          }
          frame = frame->Prev;
      }
      return STATUS_UNHANDLED_EXCEPTION;
  }
  
  
  /*******************************************************************
   *		raise_exception
   *
   * Implementation of NtRaiseException.
   */
  static NTSTATUS raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
  {
      NTSTATUS status;
  
      if (first_chance)
      {
          DWORD c;
  
          TRACE( "code=%x flags=%x addr=%p ip=%08x tid=%04x\n",
                 rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress,
                 context->Eip, GetCurrentThreadId() );
          for (c = 0; c < rec->NumberParameters; c++)
              TRACE( " info[%d]=%08lx\n", c, rec->ExceptionInformation[c] );
          if (rec->ExceptionCode == EXCEPTION_WINE_STUB)
          {
              if (rec->ExceptionInformation[1] >> 16)
                  MESSAGE( "wine: Call from %p to unimplemented function %s.%s, aborting\n",
                           rec->ExceptionAddress,
                           (char*)rec->ExceptionInformation[0], (char*)rec->ExceptionInformation[1] );
              else
                  MESSAGE( "wine: Call from %p to unimplemented function %s.%ld, aborting\n",
                           rec->ExceptionAddress,
                           (char*)rec->ExceptionInformation[0], rec->ExceptionInformation[1] );
          }
          else
          {
              TRACE(" eax=%08x ebx=%08x ecx=%08x edx=%08x esi=%08x edi=%08x\n",
                    context->Eax, context->Ebx, context->Ecx,
                    context->Edx, context->Esi, context->Edi );
              TRACE(" ebp=%08x esp=%08x cs=%04x ds=%04x es=%04x fs=%04x gs=%04x flags=%08x\n",
                    context->Ebp, context->Esp, context->SegCs, context->SegDs,
                    context->SegEs, context->SegFs, context->SegGs, context->EFlags );
          }
          status = send_debug_event( rec, TRUE, context );
          if (status == DBG_CONTINUE || status == DBG_EXCEPTION_HANDLED)
              return STATUS_SUCCESS;
  
          /* fix up instruction pointer in context for EXCEPTION_BREAKPOINT */
          if (rec->ExceptionCode == EXCEPTION_BREAKPOINT) context->Eip--;
  
          if (call_vectored_handlers( rec, context ) == EXCEPTION_CONTINUE_EXECUTION)
              return STATUS_SUCCESS;
  
          if ((status = call_stack_handlers( rec, context )) != STATUS_UNHANDLED_EXCEPTION)
              return status;
      }
  
      /* last chance exception */
  
      status = send_debug_event( rec, FALSE, context );
      if (status != DBG_CONTINUE)
      {
          if (rec->ExceptionFlags & EH_STACK_INVALID)
              WINE_ERR("Exception frame is not in stack limits => unable to dispatch exception.\n");
          else if (rec->ExceptionCode == STATUS_NONCONTINUABLE_EXCEPTION)
              WINE_ERR("Process attempted to continue execution after noncontinuable exception.\n");
          else
              WINE_ERR("Unhandled exception code %x flags %x addr %p\n",
                       rec->ExceptionCode, rec->ExceptionFlags, rec->ExceptionAddress );
          NtTerminateProcess( NtCurrentProcess(), rec->ExceptionCode );
      }
      return STATUS_SUCCESS;
  }
  
  
  #ifdef __HAVE_VM86
  /***********************************************************************
   *           save_vm86_context
   *
   * Set the register values from a vm86 structure.
   */
  static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
  {
      context->ContextFlags = CONTEXT_FULL;
      context->Eax    = vm86->regs.eax;
      context->Ebx    = vm86->regs.ebx;
      context->Ecx    = vm86->regs.ecx;
      context->Edx    = vm86->regs.edx;
      context->Esi    = vm86->regs.esi;
      context->Edi    = vm86->regs.edi;
      context->Esp    = vm86->regs.esp;
      context->Ebp    = vm86->regs.ebp;
      context->Eip    = vm86->regs.eip;
      context->SegCs  = vm86->regs.cs;
      context->SegDs  = vm86->regs.ds;
      context->SegEs  = vm86->regs.es;
      context->SegFs  = vm86->regs.fs;
      context->SegGs  = vm86->regs.gs;
      context->SegSs  = vm86->regs.ss;
      context->EFlags = vm86->regs.eflags;
  }
  
  
  /***********************************************************************
   *           restore_vm86_context
   *
   * Build a vm86 structure from the register values.
   */
  static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
  {
      vm86->regs.eax    = context->Eax;
      vm86->regs.ebx    = context->Ebx;
      vm86->regs.ecx    = context->Ecx;
      vm86->regs.edx    = context->Edx;
      vm86->regs.esi    = context->Esi;
      vm86->regs.edi    = context->Edi;
      vm86->regs.esp    = context->Esp;
      vm86->regs.ebp    = context->Ebp;
      vm86->regs.eip    = context->Eip;
      vm86->regs.cs     = context->SegCs;
      vm86->regs.ds     = context->SegDs;
      vm86->regs.es     = context->SegEs;
      vm86->regs.fs     = context->SegFs;
      vm86->regs.gs     = context->SegGs;
      vm86->regs.ss     = context->SegSs;
      vm86->regs.eflags = context->EFlags;
  }
  
  
  /**********************************************************************
   *		merge_vm86_pending_flags
   *
   * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
   * raises exception if there are pending events and VIF flag
   * has been turned on.
   *
   * Called from __wine_enter_vm86 because vm86_enter
   * doesn't check for pending events. 
   *
   * Called from raise_vm86_sti_exception to check for
   * pending events in a signal safe way.
   */
  static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
  {
      BOOL check_pending = TRUE;
      struct vm86plus_struct *vm86 =
          (struct vm86plus_struct*)x86_thread_data()->vm86_ptr;
  
      /*
       * In order to prevent a race when SIGUSR2 occurs while
       * we are returning from exception handler, pending events
       * will be rechecked after each raised exception.
       */
      while (check_pending && get_vm86_teb_info()->vm86_pending)
      {
          check_pending = FALSE;
          x86_thread_data()->vm86_ptr = NULL;
  
          /*
           * If VIF is set, throw exception.
           * Note that SIGUSR2 may turn VIF flag off so
           * VIF check must occur only when TEB.vm86_ptr is NULL.
           */
          if (vm86->regs.eflags & VIF_FLAG)
          {
              CONTEXT vcontext;
              save_vm86_context( &vcontext, vm86 );
              
              rec->ExceptionCode    = EXCEPTION_VM86_STI;
              rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
              rec->ExceptionRecord  = NULL;
              rec->NumberParameters = 0;
              rec->ExceptionAddress = (LPVOID)vcontext.Eip;
  
              vcontext.EFlags &= ~VIP_FLAG;
              get_vm86_teb_info()->vm86_pending = 0;
              raise_exception( rec, &vcontext, TRUE );
  
              restore_vm86_context( &vcontext, vm86 );
              check_pending = TRUE;
          }
  
          x86_thread_data()->vm86_ptr = vm86;
      }
  
      /*
       * Merge VIP flags in a signal safe way. This requires
       * that the following operation compiles into atomic
       * instruction.
       */
      vm86->regs.eflags |= get_vm86_teb_info()->vm86_pending;
  }
  #endif /* __HAVE_VM86 */
  
  
  #ifdef __sun
  
  /* We have to workaround two Solaris breakages:
   * - Solaris doesn't restore %ds and %es before calling the signal handler so exceptions in 16-bit
   *   code crash badly.
   * - Solaris inserts a libc trampoline to call our handler, but the trampoline expects that registers
   *   are setup correctly. So we need to insert our own trampoline below the libc trampoline to set %gs.
   */
  
  extern int sigaction_syscall( int sig, const struct sigaction *new, struct sigaction *old );
  __ASM_GLOBAL_FUNC( sigaction_syscall,
                    "movl $0x62,%eax\n\t"
                    "int $0x91\n\t"
                    "ret" )
  
  /* assume the same libc handler is used for all signals */
  static void (*libc_sigacthandler)( int signal, siginfo_t *siginfo, void *context );
  
  static void wine_sigacthandler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      struct x86_thread_data *thread_data;
  
      __asm__ __volatile__("mov %ss,%ax; mov %ax,%ds; mov %ax,%es");
  
      thread_data = (struct x86_thread_data *)get_current_teb()->SystemReserved2;
      wine_set_fs( thread_data->fs );
      wine_set_gs( thread_data->gs );
  
      libc_sigacthandler( signal, siginfo, sigcontext );
  }
  
  static int solaris_sigaction( int sig, const struct sigaction *new, struct sigaction *old )
  {
      struct sigaction real_act;
  
      if (sigaction( sig, new, old ) == -1) return -1;
  
      /* retrieve the real handler and flags with a direct syscall */
      sigaction_syscall( sig, NULL, &real_act );
      libc_sigacthandler = real_act.sa_sigaction;
      real_act.sa_sigaction = wine_sigacthandler;
      sigaction_syscall( sig, &real_act, NULL );
      return 0;
  }
  #define sigaction(sig,new,old) solaris_sigaction(sig,new,old)
  
  #endif
  
  typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
  
  extern void clear_alignment_flag(void);
  __ASM_GLOBAL_FUNC( clear_alignment_flag,
                     "pushfl\n\t"
                     __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                     "andl $~0x40000,(%esp)\n\t"
                     "popfl\n\t"
                     __ASM_CFI(".cfi_adjust_cfa_offset -4\n\t")
                     "ret" )
  
  
  /***********************************************************************
   *           init_handler
   *
   * Handler initialization when the full context is not needed.
   * Return the stack pointer to use for pushing the exception data.
   */
  static inline void *init_handler( const ucontext_t *sigcontext, WORD *fs, WORD *gs )
  {
      TEB *teb = get_current_teb();
  
      clear_alignment_flag();
  
      /* get %fs and %gs at time of the fault */
  #ifdef FS_sig
      *fs = LOWORD(FS_sig(sigcontext));
  #else
      *fs = wine_get_fs();
  #endif
  #ifdef GS_sig
      *gs = LOWORD(GS_sig(sigcontext));
  #else
      *gs = wine_get_gs();
  #endif
  
  #ifndef __sun  /* see above for Solaris handling */
      {
          struct x86_thread_data *thread_data = (struct x86_thread_data *)teb->SystemReserved2;
          wine_set_fs( thread_data->fs );
          wine_set_gs( thread_data->gs );
      }
  #endif
  
      if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
          !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
      {
          /*
           * Win16 or DOS protected mode. Note that during switch
           * from 16-bit mode to linear mode, CS may be set to system
           * segment before FS is restored. Fortunately, in this case
           * SS is still non-system segment. This is why both CS and SS
           * are checked.
           */
          return teb->WOW32Reserved;
      }
      return (void *)(ESP_sig(sigcontext) & ~3);
  }
  
  
  /***********************************************************************
   *           save_fpu
   *
   * Save the thread FPU context.
   */
  static inline void save_fpu( CONTEXT *context )
  {
  #ifdef __GNUC__
      context->ContextFlags |= CONTEXT_FLOATING_POINT;
      __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
  #endif
  }
  
  
  /***********************************************************************
   *           restore_fpu
   *
   * Restore the FPU context to a sigcontext.
   */
  static inline void restore_fpu( const CONTEXT *context )
  {
      FLOATING_SAVE_AREA float_status = context->FloatSave;
      /* reset the current interrupt status */
      float_status.StatusWord &= float_status.ControlWord | 0xffffff80;
  #ifdef __GNUC__
      __asm__ __volatile__( "frstor %0; fwait" : : "m" (float_status) );
  #endif  /* __GNUC__ */
  }
  
  
  /***********************************************************************
   *           restore_fpux
   *
   * Restore the FPU extended context to a sigcontext.
   */
  static inline void restore_fpux( const CONTEXT *context )
  {
  #ifdef __GNUC__
      /* we have to enforce alignment by hand */
      char buffer[sizeof(XMM_SAVE_AREA32) + 16];
      XMM_SAVE_AREA32 *state = (XMM_SAVE_AREA32 *)(((ULONG_PTR)buffer + 15) & ~15);
  
      memcpy( state, context->ExtendedRegisters, sizeof(*state) );
      /* reset the current interrupt status */
      state->StatusWord &= state->ControlWord | 0xff80;
      __asm__ __volatile__( "fxrstor %0" : : "m" (*state) );
  #endif
  }
  
  
  /***********************************************************************
   *           fpux_to_fpu
   *
   * Build a standard FPU context from an extended one.
   */
  static void fpux_to_fpu( FLOATING_SAVE_AREA *fpu, const XMM_SAVE_AREA32 *fpux )
  {
      unsigned int i, tag, stack_top;
  
      fpu->ControlWord   = fpux->ControlWord | 0xffff0000;
      fpu->StatusWord    = fpux->StatusWord | 0xffff0000;
      fpu->ErrorOffset   = fpux->ErrorOffset;
      fpu->ErrorSelector = fpux->ErrorSelector | (fpux->ErrorOpcode << 16);
      fpu->DataOffset    = fpux->DataOffset;
      fpu->DataSelector  = fpux->DataSelector;
      fpu->Cr0NpxState   = fpux->StatusWord | 0xffff0000;
  
      stack_top = (fpux->StatusWord >> 11) & 7;
      fpu->TagWord = 0xffff0000;
      for (i = 0; i < 8; i++)
      {
          memcpy( &fpu->RegisterArea[10 * i], &fpux->FloatRegisters[i], 10 );
          if (!(fpux->TagWord & (1 << i))) tag = 3;  /* empty */
          else
          {
              const M128A *reg = &fpux->FloatRegisters[(i - stack_top) & 7];
              if ((reg->High & 0x7fff) == 0x7fff)  /* exponent all ones */
              {
                  tag = 2;  /* special */
              }
              else if (!(reg->High & 0x7fff))  /* exponent all zeroes */
              {
                  if (reg->Low) tag = 2;  /* special */
                  else tag = 1;  /* zero */
              }
              else
              {
                  if (reg->Low >> 63) tag = 0;  /* valid */
                  else tag = 2;  /* special */
              }
          }
          fpu->TagWord |= tag << (2 * i);
      }
  }
  
  
  /***********************************************************************
   *           save_context
   *
   * Build a context structure from the signal info.
   */
  static inline void save_context( CONTEXT *context, const ucontext_t *sigcontext, WORD fs, WORD gs )
  {
      FLOATING_SAVE_AREA *fpu = FPU_sig(sigcontext);
      XMM_SAVE_AREA32 *fpux = FPUX_sig(sigcontext);
  
      memset(context, 0, sizeof(*context));
      context->ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
      context->Eax          = EAX_sig(sigcontext);
      context->Ebx          = EBX_sig(sigcontext);
      context->Ecx          = ECX_sig(sigcontext);
      context->Edx          = EDX_sig(sigcontext);
      context->Esi          = ESI_sig(sigcontext);
      context->Edi          = EDI_sig(sigcontext);
      context->Ebp          = EBP_sig(sigcontext);
      context->EFlags       = EFL_sig(sigcontext);
      context->Eip          = EIP_sig(sigcontext);
      context->Esp          = ESP_sig(sigcontext);
      context->SegCs        = LOWORD(CS_sig(sigcontext));
      context->SegDs        = LOWORD(DS_sig(sigcontext));
      context->SegEs        = LOWORD(ES_sig(sigcontext));
      context->SegFs        = fs;
      context->SegGs        = gs;
      context->SegSs        = LOWORD(SS_sig(sigcontext));
      context->Dr0          = x86_thread_data()->dr0;
      context->Dr1          = x86_thread_data()->dr1;
      context->Dr2          = x86_thread_data()->dr2;
      context->Dr3          = x86_thread_data()->dr3;
      context->Dr6          = x86_thread_data()->dr6;
      context->Dr7          = x86_thread_data()->dr7;
  
      if (fpu)
      {
          context->ContextFlags |= CONTEXT_FLOATING_POINT;
          context->FloatSave = *fpu;
      }
      if (fpux)
      {
          context->ContextFlags |= CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS;
          memcpy( context->ExtendedRegisters, fpux, sizeof(*fpux) );
          fpux_support = TRUE;
          if (!fpu) fpux_to_fpu( &context->FloatSave, fpux );
      }
      if (!fpu && !fpux) save_fpu( context );
  }
  
  
  /***********************************************************************
   *           restore_context
   *
   * Restore the signal info from the context.
   */
  static inline void restore_context( const CONTEXT *context, ucontext_t *sigcontext )
  {
      FLOATING_SAVE_AREA *fpu = FPU_sig(sigcontext);
      XMM_SAVE_AREA32 *fpux = FPUX_sig(sigcontext);
  
      x86_thread_data()->dr0 = context->Dr0;
      x86_thread_data()->dr1 = context->Dr1;
      x86_thread_data()->dr2 = context->Dr2;
      x86_thread_data()->dr3 = context->Dr3;
      x86_thread_data()->dr6 = context->Dr6;
      x86_thread_data()->dr7 = context->Dr7;
      EAX_sig(sigcontext) = context->Eax;
      EBX_sig(sigcontext) = context->Ebx;
      ECX_sig(sigcontext) = context->Ecx;
      EDX_sig(sigcontext) = context->Edx;
      ESI_sig(sigcontext) = context->Esi;
      EDI_sig(sigcontext) = context->Edi;
      EBP_sig(sigcontext) = context->Ebp;
      EFL_sig(sigcontext) = context->EFlags;
      EIP_sig(sigcontext) = context->Eip;
      ESP_sig(sigcontext) = context->Esp;
      CS_sig(sigcontext)  = context->SegCs;
      DS_sig(sigcontext)  = context->SegDs;
      ES_sig(sigcontext)  = context->SegEs;
      SS_sig(sigcontext)  = context->SegSs;
  #ifdef GS_sig
      GS_sig(sigcontext)  = context->SegGs;
  #else
      wine_set_gs( context->SegGs );
  #endif
  #ifdef FS_sig
      FS_sig(sigcontext)  = context->SegFs;
  #else
      wine_set_fs( context->SegFs );
  #endif
  
      if (fpu) *fpu = context->FloatSave;
      if (fpux) memcpy( fpux, context->ExtendedRegisters, sizeof(*fpux) );
      if (!fpu && !fpux) restore_fpu( context );
  }
  
  
  /***********************************************************************
   *		RtlCaptureContext (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( RtlCaptureContext, 4,
                      "pushl %eax\n\t"
                      __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                      "movl 8(%esp),%eax\n\t"    /* context */
                      "movl $0x10007,(%eax)\n\t" /* context->ContextFlags */
                      "movw %gs,0x8c(%eax)\n\t"  /* context->SegGs */
                      "movw %fs,0x90(%eax)\n\t"  /* context->SegFs */
                      "movw %es,0x94(%eax)\n\t"  /* context->SegEs */
                      "movw %ds,0x98(%eax)\n\t"  /* context->SegDs */
                      "movl %edi,0x9c(%eax)\n\t" /* context->Edi */
                      "movl %esi,0xa0(%eax)\n\t" /* context->Esi */
                      "movl %ebx,0xa4(%eax)\n\t" /* context->Ebx */
                      "movl %edx,0xa8(%eax)\n\t" /* context->Edx */
                      "movl %ecx,0xac(%eax)\n\t" /* context->Ecx */
                      "movl 0(%ebp),%edx\n\t"
                      "movl %edx,0xb4(%eax)\n\t" /* context->Ebp */
                      "movl 4(%ebp),%edx\n\t"
                      "movl %edx,0xb8(%eax)\n\t" /* context->Eip */
                      "movw %cs,0xbc(%eax)\n\t"  /* context->SegCs */
                      "pushfl\n\t"
                      __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                      "popl 0xc0(%eax)\n\t"      /* context->EFlags */
                      __ASM_CFI(".cfi_adjust_cfa_offset -4\n\t")
                      "leal 8(%ebp),%edx\n\t"
                      "movl %edx,0xc4(%eax)\n\t" /* context->Esp */
                      "movw %ss,0xc8(%eax)\n\t"  /* context->SegSs */
                      "popl 0xb0(%eax)\n\t"      /* context->Eax */
                      __ASM_CFI(".cfi_adjust_cfa_offset -4\n\t")
                      "ret $4" )
  
  /***********************************************************************
   *           set_full_cpu_context
   *
   * Set the new CPU context.
   */
  extern void set_full_cpu_context( const CONTEXT *context );
  __ASM_GLOBAL_FUNC( set_full_cpu_context,
                     "movl 4(%esp),%ecx\n\t"
                     "movw 0x8c(%ecx),%gs\n\t"  /* SegGs */
                     "movw 0x90(%ecx),%fs\n\t"  /* SegFs */
                     "movw 0x94(%ecx),%es\n\t"  /* SegEs */
                     "movl 0x9c(%ecx),%edi\n\t" /* Edi */
                     "movl 0xa0(%ecx),%esi\n\t" /* Esi */
                     "movl 0xa4(%ecx),%ebx\n\t" /* Ebx */
                     "movl 0xb4(%ecx),%ebp\n\t" /* Ebp */
                     "movw %ss,%ax\n\t"
                     "cmpw 0xc8(%ecx),%ax\n\t"  /* SegSs */
                     "jne 1f\n\t"
                     /* As soon as we have switched stacks the context structure could
                      * be invalid (when signal handlers are executed for example). Copy
                      * values on the target stack before changing ESP. */
                     "movl 0xc4(%ecx),%eax\n\t" /* Esp */
                     "leal -4*4(%eax),%eax\n\t"
                     "movl 0xc0(%ecx),%edx\n\t" /* EFlags */
                     "movl %edx,3*4(%eax)\n\t"
                     "movl 0xbc(%ecx),%edx\n\t" /* SegCs */
                     "movl %edx,2*4(%eax)\n\t"
                     "movl 0xb8(%ecx),%edx\n\t" /* Eip */
                     "movl %edx,1*4(%eax)\n\t"
                     "movl 0xb0(%ecx),%edx\n\t" /* Eax */
                     "movl %edx,0*4(%eax)\n\t"
                     "pushl 0x98(%ecx)\n\t"     /* SegDs */
                     "movl 0xa8(%ecx),%edx\n\t" /* Edx */
                     "movl 0xac(%ecx),%ecx\n\t" /* Ecx */
                     "popl %ds\n\t"
                     "movl %eax,%esp\n\t"
                     "popl %eax\n\t"
                     "iret\n"
                     /* Restore the context when the stack segment changes. We can't use
                      * the same code as above because we do not know if the stack segment
                      * is 16 or 32 bit, and 'movl' will throw an exception when we try to
                      * access memory above the limit. */
                     "1:\n\t"
                     "movl 0xa8(%ecx),%edx\n\t" /* Edx */
                     "movl 0xb0(%ecx),%eax\n\t" /* Eax */
                     "movw 0xc8(%ecx),%ss\n\t"  /* SegSs */
                     "movl 0xc4(%ecx),%esp\n\t" /* Esp */
                     "pushl 0xc0(%ecx)\n\t"     /* EFlags */
                     "pushl 0xbc(%ecx)\n\t"     /* SegCs */
                     "pushl 0xb8(%ecx)\n\t"     /* Eip */
                     "pushl 0x98(%ecx)\n\t"     /* SegDs */
                     "movl 0xac(%ecx),%ecx\n\t" /* Ecx */
                     "popl %ds\n\t"
                     "iret" )
  
  
  /***********************************************************************
   *           set_cpu_context
   *
   * Set the new CPU context. Used by NtSetContextThread.
   */
  void DECLSPEC_HIDDEN set_cpu_context( const CONTEXT *context )
  {
      DWORD flags = context->ContextFlags & ~CONTEXT_i386;
  
      if ((flags & CONTEXT_EXTENDED_REGISTERS) && fpux_support) restore_fpux( context );
      else if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
  
      if (flags & CONTEXT_DEBUG_REGISTERS)
      {
          x86_thread_data()->dr0 = context->Dr0;
          x86_thread_data()->dr1 = context->Dr1;
          x86_thread_data()->dr2 = context->Dr2;
          x86_thread_data()->dr3 = context->Dr3;
          x86_thread_data()->dr6 = context->Dr6;
          x86_thread_data()->dr7 = context->Dr7;
      }
      if (flags & CONTEXT_FULL)
      {
          if (!(flags & CONTEXT_CONTROL))
              FIXME( "setting partial context (%x) not supported\n", flags );
          else if (flags & CONTEXT_SEGMENTS)
              set_full_cpu_context( context );
          else
          {
              CONTEXT newcontext = *context;
              newcontext.SegDs = wine_get_ds();
              newcontext.SegEs = wine_get_es();
              newcontext.SegFs = wine_get_fs();
              newcontext.SegGs = wine_get_gs();
              set_full_cpu_context( &newcontext );
          }
      }
  }
  
  
  /***********************************************************************
   *           context_to_server
   *
   * Convert a register context to the server format.
   */
  NTSTATUS context_to_server( context_t *to, const CONTEXT *from )
  {
      DWORD flags = from->ContextFlags & ~CONTEXT_i386;  /* get rid of CPU id */
  
      memset( to, 0, sizeof(*to) );
      to->cpu = CPU_x86;
  
      if (flags & CONTEXT_CONTROL)
      {
          to->flags |= SERVER_CTX_CONTROL;
          to->ctl.i386_regs.ebp    = from->Ebp;
          to->ctl.i386_regs.esp    = from->Esp;
          to->ctl.i386_regs.eip    = from->Eip;
          to->ctl.i386_regs.cs     = from->SegCs;
          to->ctl.i386_regs.ss     = from->SegSs;
          to->ctl.i386_regs.eflags = from->EFlags;
      }
      if (flags & CONTEXT_INTEGER)
      {
          to->flags |= SERVER_CTX_INTEGER;
          to->integer.i386_regs.eax = from->Eax;
          to->integer.i386_regs.ebx = from->Ebx;
          to->integer.i386_regs.ecx = from->Ecx;
          to->integer.i386_regs.edx = from->Edx;
          to->integer.i386_regs.esi = from->Esi;
          to->integer.i386_regs.edi = from->Edi;
      }
      if (flags & CONTEXT_SEGMENTS)
      {
          to->flags |= SERVER_CTX_SEGMENTS;
          to->seg.i386_regs.ds = from->SegDs;
          to->seg.i386_regs.es = from->SegEs;
          to->seg.i386_regs.fs = from->SegFs;
          to->seg.i386_regs.gs = from->SegGs;
      }
      if (flags & CONTEXT_FLOATING_POINT)
      {
          to->flags |= SERVER_CTX_FLOATING_POINT;
          to->fp.i386_regs.ctrl     = from->FloatSave.ControlWord;
          to->fp.i386_regs.status   = from->FloatSave.StatusWord;
          to->fp.i386_regs.tag      = from->FloatSave.TagWord;
          to->fp.i386_regs.err_off  = from->FloatSave.ErrorOffset;
          to->fp.i386_regs.err_sel  = from->FloatSave.ErrorSelector;
          to->fp.i386_regs.data_off = from->FloatSave.DataOffset;
          to->fp.i386_regs.data_sel = from->FloatSave.DataSelector;
          to->fp.i386_regs.cr0npx   = from->FloatSave.Cr0NpxState;
          memcpy( to->fp.i386_regs.regs, from->FloatSave.RegisterArea, sizeof(to->fp.i386_regs.regs) );
      }
      if (flags & CONTEXT_DEBUG_REGISTERS)
      {
          to->flags |= SERVER_CTX_DEBUG_REGISTERS;
          to->debug.i386_regs.dr0 = from->Dr0;
          to->debug.i386_regs.dr1 = from->Dr1;
          to->debug.i386_regs.dr2 = from->Dr2;
          to->debug.i386_regs.dr3 = from->Dr3;
          to->debug.i386_regs.dr6 = from->Dr6;
          to->debug.i386_regs.dr7 = from->Dr7;
      }
      if (flags & CONTEXT_EXTENDED_REGISTERS)
      {
          to->flags |= SERVER_CTX_EXTENDED_REGISTERS;
          memcpy( to->ext.i386_regs, from->ExtendedRegisters, sizeof(to->ext.i386_regs) );
      }
      return STATUS_SUCCESS;
  }
  
  
  /***********************************************************************
   *           context_from_server
   *
   * Convert a register context from the server format.
   */
  NTSTATUS context_from_server( CONTEXT *to, const context_t *from )
  {
      if (from->cpu != CPU_x86) return STATUS_INVALID_PARAMETER;
  
      to->ContextFlags = CONTEXT_i386;
      if (from->flags & SERVER_CTX_CONTROL)
      {
          to->ContextFlags |= CONTEXT_CONTROL;
          to->Ebp    = from->ctl.i386_regs.ebp;
          to->Esp    = from->ctl.i386_regs.esp;
          to->Eip    = from->ctl.i386_regs.eip;
          to->SegCs  = from->ctl.i386_regs.cs;
          to->SegSs  = from->ctl.i386_regs.ss;
          to->EFlags = from->ctl.i386_regs.eflags;
      }
      if (from->flags & SERVER_CTX_INTEGER)
      {
          to->ContextFlags |= CONTEXT_INTEGER;
          to->Eax = from->integer.i386_regs.eax;
          to->Ebx = from->integer.i386_regs.ebx;
          to->Ecx = from->integer.i386_regs.ecx;
          to->Edx = from->integer.i386_regs.edx;
          to->Esi = from->integer.i386_regs.esi;
          to->Edi = from->integer.i386_regs.edi;
      }
      if (from->flags & SERVER_CTX_SEGMENTS)
      {
          to->ContextFlags |= CONTEXT_SEGMENTS;
          to->SegDs = from->seg.i386_regs.ds;
          to->SegEs = from->seg.i386_regs.es;
          to->SegFs = from->seg.i386_regs.fs;
          to->SegGs = from->seg.i386_regs.gs;
      }
      if (from->flags & SERVER_CTX_FLOATING_POINT)
      {
          to->ContextFlags |= CONTEXT_FLOATING_POINT;
          to->FloatSave.ControlWord   = from->fp.i386_regs.ctrl;
          to->FloatSave.StatusWord    = from->fp.i386_regs.status;
          to->FloatSave.TagWord       = from->fp.i386_regs.tag;
          to->FloatSave.ErrorOffset   = from->fp.i386_regs.err_off;
          to->FloatSave.ErrorSelector = from->fp.i386_regs.err_sel;
          to->FloatSave.DataOffset    = from->fp.i386_regs.data_off;
          to->FloatSave.DataSelector  = from->fp.i386_regs.data_sel;
          to->FloatSave.Cr0NpxState   = from->fp.i386_regs.cr0npx;
          memcpy( to->FloatSave.RegisterArea, from->fp.i386_regs.regs, sizeof(to->FloatSave.RegisterArea) );
      }
      if (from->flags & SERVER_CTX_DEBUG_REGISTERS)
      {
          to->ContextFlags |= CONTEXT_DEBUG_REGISTERS;
          to->Dr0 = from->debug.i386_regs.dr0;
          to->Dr1 = from->debug.i386_regs.dr1;
          to->Dr2 = from->debug.i386_regs.dr2;
          to->Dr3 = from->debug.i386_regs.dr3;
          to->Dr6 = from->debug.i386_regs.dr6;
          to->Dr7 = from->debug.i386_regs.dr7;
      }
      if (from->flags & SERVER_CTX_EXTENDED_REGISTERS)
      {
          to->ContextFlags |= CONTEXT_EXTENDED_REGISTERS;
          memcpy( to->ExtendedRegisters, from->ext.i386_regs, sizeof(to->ExtendedRegisters) );
      }
      return STATUS_SUCCESS;
  }
  
  
  /***********************************************************************
   *              NtSetContextThread  (NTDLL.@)
   *              ZwSetContextThread  (NTDLL.@)
   */
  NTSTATUS WINAPI NtSetContextThread( HANDLE handle, const CONTEXT *context )
  {
      NTSTATUS ret = STATUS_SUCCESS;
      BOOL self = (handle == GetCurrentThread());
  
      /* debug registers require a server call */
      if (self && (context->ContextFlags & (CONTEXT_DEBUG_REGISTERS & ~CONTEXT_i386)))
          self = (x86_thread_data()->dr0 == context->Dr0 &&
                  x86_thread_data()->dr1 == context->Dr1 &&
                  x86_thread_data()->dr2 == context->Dr2 &&
                  x86_thread_data()->dr3 == context->Dr3 &&
                  x86_thread_data()->dr6 == context->Dr6 &&
                  x86_thread_data()->dr7 == context->Dr7);
  
      if (!self) ret = set_thread_context( handle, context, &self );
  
      if (self && ret == STATUS_SUCCESS) set_cpu_context( context );
      return ret;
  }
  
  
  /***********************************************************************
   *              NtGetContextThread  (NTDLL.@)
   *              ZwGetContextThread  (NTDLL.@)
   *
   * Note: we use a small assembly wrapper to save the necessary registers
   *       in case we are fetching the context of the current thread.
   */
  NTSTATUS CDECL DECLSPEC_HIDDEN __regs_NtGetContextThread( DWORD edi, DWORD esi, DWORD ebx, DWORD eflags,
                                                            DWORD ebp, DWORD retaddr, HANDLE handle,
                                                            CONTEXT *context )
  {
      NTSTATUS ret;
      DWORD needed_flags = context->ContextFlags & ~CONTEXT_i386;
      BOOL self = (handle == GetCurrentThread());
  
      /* debug registers require a server call */
      if (needed_flags & CONTEXT_DEBUG_REGISTERS) self = FALSE;
  
      if (!self)
      {
          if ((ret = get_thread_context( handle, context, &self ))) return ret;
          needed_flags &= ~context->ContextFlags;
      }
  
      if (self)
      {
          if (needed_flags & CONTEXT_INTEGER)
          {
              context->Eax = 0;
              context->Ebx = ebx;
              context->Ecx = 0;
              context->Edx = 0;
              context->Esi = esi;
              context->Edi = edi;
              context->ContextFlags |= CONTEXT_INTEGER;
          }
          if (needed_flags & CONTEXT_CONTROL)
          {
              context->Ebp    = ebp;
              context->Esp    = (DWORD)&retaddr;
              context->Eip    = *(&edi - 1);
              context->SegCs  = wine_get_cs();
              context->SegSs  = wine_get_ss();
              context->EFlags = eflags;
              context->ContextFlags |= CONTEXT_CONTROL;
          }
          if (needed_flags & CONTEXT_SEGMENTS)
          {
              context->SegDs = wine_get_ds();
              context->SegEs = wine_get_es();
              context->SegFs = wine_get_fs();
              context->SegGs = wine_get_gs();
              context->ContextFlags |= CONTEXT_SEGMENTS;
          }
          if (needed_flags & CONTEXT_FLOATING_POINT) save_fpu( context );
          /* FIXME: extended floating point */
          /* update the cached version of the debug registers */
          if (context->ContextFlags & (CONTEXT_DEBUG_REGISTERS & ~CONTEXT_i386))
          {
              x86_thread_data()->dr0 = context->Dr0;
              x86_thread_data()->dr1 = context->Dr1;
              x86_thread_data()->dr2 = context->Dr2;
              x86_thread_data()->dr3 = context->Dr3;
              x86_thread_data()->dr6 = context->Dr6;
              x86_thread_data()->dr7 = context->Dr7;
          }
      }
  
      if (context->ContextFlags & (CONTEXT_INTEGER & ~CONTEXT_i386))
          TRACE( "%p: eax=%08x ebx=%08x ecx=%08x edx=%08x esi=%08x edi=%08x\n", handle,
                 context->Eax, context->Ebx, context->Ecx, context->Edx, context->Esi, context->Edi );
      if (context->ContextFlags & (CONTEXT_CONTROL & ~CONTEXT_i386))
          TRACE( "%p: ebp=%08x esp=%08x eip=%08x cs=%04x ss=%04x flags=%08x\n", handle,
                 context->Ebp, context->Esp, context->Eip, context->SegCs, context->SegSs, context->EFlags );
      if (context->ContextFlags & (CONTEXT_SEGMENTS & ~CONTEXT_i386))
          TRACE( "%p: ds=%04x es=%04x fs=%04x gs=%04x\n", handle,
                 context->SegDs, context->SegEs, context->SegFs, context->SegGs );
      if (context->ContextFlags & (CONTEXT_DEBUG_REGISTERS & ~CONTEXT_i386))
          TRACE( "%p: dr0=%08x dr1=%08x dr2=%08x dr3=%08x dr6=%08x dr7=%08x\n", handle,
                 context->Dr0, context->Dr1, context->Dr2, context->Dr3, context->Dr6, context->Dr7 );
  
      return STATUS_SUCCESS;
  }
  __ASM_STDCALL_FUNC( NtGetContextThread, 8,
                      "pushl %ebp\n\t"
                      __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                      __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                      "movl %esp,%ebp\n\t"
                      __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                      "pushfl\n\t"
                      "pushl %ebx\n\t"
                      __ASM_CFI(".cfi_rel_offset %ebx,-8\n\t")
                      "pushl %esi\n\t"
                      __ASM_CFI(".cfi_rel_offset %esi,-12\n\t")
                      "pushl %edi\n\t"
                      __ASM_CFI(".cfi_rel_offset %edi,-16\n\t")
                      "call " __ASM_NAME("__regs_NtGetContextThread") "\n\t"
                      "leave\n\t"
                      __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                      __ASM_CFI(".cfi_same_value %ebp\n\t")
                      "ret $8" )
  
  
  /***********************************************************************
   *           is_privileged_instr
   *
   * Check if the fault location is a privileged instruction.
   * Based on the instruction emulation code in dlls/kernel/instr.c.
   */
  static inline DWORD is_privileged_instr( CONTEXT *context )
  {
      const BYTE *instr;
      unsigned int prefix_count = 0;
  
      if (!wine_ldt_is_system( context->SegCs )) return 0;
      instr = (BYTE *)context->Eip;
  
      for (;;) switch(*instr)
      {
      /* instruction prefixes */
      case 0x2e:  /* %cs: */
      case 0x36:  /* %ss: */
      case 0x3e:  /* %ds: */
      case 0x26:  /* %es: */
      case 0x64:  /* %fs: */
      case 0x65:  /* %gs: */
      case 0x66:  /* opcode size */
      case 0x67:  /* addr size */
      case 0xf0:  /* lock */
      case 0xf2:  /* repne */
      case 0xf3:  /* repe */
          if (++prefix_count >= 15) return EXCEPTION_ILLEGAL_INSTRUCTION;
          instr++;
          continue;
  
      case 0x0f: /* extended instruction */
          switch(instr[1])
          {
          case 0x20: /* mov crX, reg */
          case 0x21: /* mov drX, reg */
          case 0x22: /* mov reg, crX */
          case 0x23: /* mov reg drX */
              return EXCEPTION_PRIV_INSTRUCTION;
          }
          return 0;
      case 0x6c: /* insb (%dx) */
      case 0x6d: /* insl (%dx) */
      case 0x6e: /* outsb (%dx) */
      case 0x6f: /* outsl (%dx) */
      case 0xcd: /* int $xx */
      case 0xe4: /* inb al,XX */
      case 0xe5: /* in (e)ax,XX */
      case 0xe6: /* outb XX,al */
      case 0xe7: /* out XX,(e)ax */
      case 0xec: /* inb (%dx),%al */
      case 0xed: /* inl (%dx),%eax */
      case 0xee: /* outb %al,(%dx) */
      case 0xef: /* outl %eax,(%dx) */
      case 0xf4: /* hlt */
      case 0xfa: /* cli */
      case 0xfb: /* sti */
          return EXCEPTION_PRIV_INSTRUCTION;
      default:
          return 0;
      }
  }
  
  
  /***********************************************************************
   *           handle_interrupt
   *
   * Handle an interrupt.
   */
  static inline BOOL handle_interrupt( unsigned int interrupt, EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      switch(interrupt)
      {
      case 0x2d:
          context->Eip += 3;
          rec->ExceptionCode = EXCEPTION_BREAKPOINT;
          rec->ExceptionAddress = (void *)context->Eip;
          rec->NumberParameters = is_wow64 ? 1 : 3;
          rec->ExceptionInformation[0] = context->Eax;
          rec->ExceptionInformation[1] = context->Ecx;
          rec->ExceptionInformation[2] = context->Edx;
          return TRUE;
      default:
          return FALSE;
      }
  }
  
  
  /***********************************************************************
   *           check_invalid_gs
   *
   * Check for fault caused by invalid %gs value (some copy protection schemes mess with it).
   */
  static inline BOOL check_invalid_gs( CONTEXT *context )
  {
      unsigned int prefix_count = 0;
      const BYTE *instr = (BYTE *)context->Eip;
      WORD system_gs = x86_thread_data()->gs;
  
      if (context->SegGs == system_gs) return FALSE;
      if (!wine_ldt_is_system( context->SegCs )) return FALSE;
      /* only handle faults in system libraries */
      if (virtual_is_valid_code_address( instr, 1 )) return FALSE;
  
      for (;;) switch(*instr)
      {
      /* instruction prefixes */
      case 0x2e:  /* %cs: */
      case 0x36:  /* %ss: */
      case 0x3e:  /* %ds: */
      case 0x26:  /* %es: */
      case 0x64:  /* %fs: */
      case 0x66:  /* opcode size */
      case 0x67:  /* addr size */
      case 0xf0:  /* lock */
      case 0xf2:  /* repne */
      case 0xf3:  /* repe */
          if (++prefix_count >= 15) return FALSE;
          instr++;
          continue;
      case 0x65:  /* %gs: */
          TRACE( "%04x/%04x at %p, fixing up\n", context->SegGs, system_gs, instr );
          context->SegGs = system_gs;
          return TRUE;
      default:
          return FALSE;
      }
  }
  
  
  #include "pshpack1.h"
  union atl_thunk
  {
      struct
      {
          DWORD movl;  /* movl this,4(%esp) */
          DWORD this;
          BYTE  jmp;   /* jmp func */
          int   func;
      } t1;
      struct
      {
          BYTE  movl;  /* movl this,ecx */
          DWORD this;
          BYTE  jmp;   /* jmp func */
          int   func;
      } t2;
      struct
      {
          BYTE  movl1; /* movl this,edx */
          DWORD this;
          BYTE  movl2; /* movl func,ecx */
          DWORD func;
          WORD  jmp;   /* jmp ecx */
      } t3;
      struct
      {
          BYTE  movl1; /* movl this,ecx */
          DWORD this;
          BYTE  movl2; /* movl func,eax */
          DWORD func;
          WORD  jmp;   /* jmp eax */
      } t4;
      struct
      {
          DWORD inst1; /* pop ecx
                        * pop eax
                        * push ecx
                        * jmp 4(%eax) */
          WORD  inst2;
      } t5;
  };
  #include "poppack.h"
  
  /**********************************************************************
   *		check_atl_thunk
   *
   * Check if code destination is an ATL thunk, and emulate it if so.
   */
  static BOOL check_atl_thunk( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      const union atl_thunk *thunk = (const union atl_thunk *)rec->ExceptionInformation[1];
      union atl_thunk thunk_copy;
      SIZE_T thunk_len;
  
      thunk_len = virtual_uninterrupted_read_memory( thunk, &thunk_copy, sizeof(*thunk) );
      if (!thunk_len) return FALSE;
  
      if (thunk_len >= sizeof(thunk_copy.t1) && thunk_copy.t1.movl == 0x042444c7 &&
                                                thunk_copy.t1.jmp == 0xe9)
      {
          if (!virtual_uninterrupted_write_memory( (DWORD *)context->Esp + 1,
                                                   &thunk_copy.t1.this, sizeof(DWORD) ))
          {
              context->Eip = (DWORD_PTR)(&thunk->t1.func + 1) + thunk_copy.t1.func;
              TRACE( "emulating ATL thunk type 1 at %p, func=%08x arg=%08x\n",
                     thunk, context->Eip, thunk_copy.t1.this );
              return TRUE;
          }
      }
      else if (thunk_len >= sizeof(thunk_copy.t2) && thunk_copy.t2.movl == 0xb9 &&
                                                     thunk_copy.t2.jmp == 0xe9)
      {
          context->Ecx = thunk_copy.t2.this;
          context->Eip = (DWORD_PTR)(&thunk->t2.func + 1) + thunk_copy.t2.func;
          TRACE( "emulating ATL thunk type 2 at %p, func=%08x ecx=%08x\n",
                 thunk, context->Eip, context->Ecx );
          return TRUE;
      }
      else if (thunk_len >= sizeof(thunk_copy.t3) && thunk_copy.t3.movl1 == 0xba &&
                                                     thunk_copy.t3.movl2 == 0xb9 &&
                                                     thunk_copy.t3.jmp == 0xe1ff)
      {
          context->Edx = thunk_copy.t3.this;
          context->Ecx = thunk_copy.t3.func;
          context->Eip = thunk_copy.t3.func;
          TRACE( "emulating ATL thunk type 3 at %p, func=%08x ecx=%08x edx=%08x\n",
                 thunk, context->Eip, context->Ecx, context->Edx );
          return TRUE;
      }
      else if (thunk_len >= sizeof(thunk_copy.t4) && thunk_copy.t4.movl1 == 0xb9 &&
                                                     thunk_copy.t4.movl2 == 0xb8 &&
                                                     thunk_copy.t4.jmp == 0xe0ff)
      {
          context->Ecx = thunk_copy.t4.this;
          context->Eax = thunk_copy.t4.func;
          context->Eip = thunk_copy.t4.func;
          TRACE( "emulating ATL thunk type 4 at %p, func=%08x eax=%08x ecx=%08x\n",
                 thunk, context->Eip, context->Eax, context->Ecx );
          return TRUE;
      }
      else if (thunk_len >= sizeof(thunk_copy.t5) && thunk_copy.t5.inst1 == 0xff515859 &&
                                                     thunk_copy.t5.inst2 == 0x0460)
      {
          DWORD func, stack[2];
          if (virtual_uninterrupted_read_memory( (DWORD *)context->Esp,
              stack, sizeof(stack) ) == sizeof(stack) &&
              virtual_uninterrupted_read_memory( (DWORD *)stack[1] + 1,
              &func, sizeof(DWORD) ) == sizeof(DWORD) &&
              !virtual_uninterrupted_write_memory( (DWORD *)context->Esp + 1, &stack[0], sizeof(stack[0]) ))
          {
              context->Ecx = stack[0];
              context->Eax = stack[1];
              context->Esp = context->Esp + sizeof(DWORD);
              context->Eip = func;
              TRACE( "emulating ATL thunk type 5 at %p, func=%08x eax=%08x ecx=%08x esp=%08x\n",
                     thunk, context->Eip, context->Eax, context->Ecx, context->Esp );
              return TRUE;
          }
      }
  
      return FALSE;
  }
  
  
  /***********************************************************************
   *           setup_exception_record
   *
   * Setup the exception record and context on the thread stack.
   */
  static EXCEPTION_RECORD *setup_exception_record( ucontext_t *sigcontext, void *stack_ptr,
                                                   WORD fs, WORD gs, raise_func func )
  {
      struct stack_layout
      {
          void             *ret_addr;      /* return address from raise_func */
          EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
          CONTEXT          *context_ptr;   /* second arg for raise_func */
          CONTEXT           context;
          EXCEPTION_RECORD  rec;
          DWORD             ebp;
          DWORD             eip;
      } *stack = stack_ptr;
      DWORD exception_code = 0;
  
      /* stack sanity checks */
  
      if ((char *)stack >= (char *)get_signal_stack() &&
          (char *)stack < (char *)get_signal_stack() + signal_stack_size)
      {
          WINE_ERR( "nested exception on signal stack in thread %04x eip %08x esp %08x stack %p-%p\n",
                    GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
                    (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
                    NtCurrentTeb()->Tib.StackBase );
          abort_thread(1);
      }
  
      if (stack - 1 > stack || /* check for overflow in subtraction */
          (char *)stack <= (char *)NtCurrentTeb()->DeallocationStack ||
          (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
      {
          WARN( "exception outside of stack limits in thread %04x eip %08x esp %08x stack %p-%p\n",
                GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
                (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
                NtCurrentTeb()->Tib.StackBase );
      }
      else if ((char *)(stack - 1) < (char *)NtCurrentTeb()->DeallocationStack + 4096)
      {
          /* stack overflow on last page, unrecoverable */
          UINT diff = (char *)NtCurrentTeb()->DeallocationStack + 4096 - (char *)(stack - 1);
          WINE_ERR( "stack overflow %u bytes in thread %04x eip %08x esp %08x stack %p-%p-%p\n",
                    diff, GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
                    (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->DeallocationStack,
                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
          abort_thread(1);
      }
      else if ((char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit)
      {
          /* stack access below stack limit, may be recoverable */
          if (virtual_handle_stack_fault( stack - 1 )) exception_code = EXCEPTION_STACK_OVERFLOW;
          else
          {
              UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)(stack - 1);
              WINE_ERR( "stack overflow %u bytes in thread %04x eip %08x esp %08x stack %p-%p-%p\n",
                        diff, GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
                        (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->DeallocationStack,
                        NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
              abort_thread(1);
          }
      }
  
      stack--;  /* push the stack_layout structure */
  #if defined(VALGRIND_MAKE_MEM_UNDEFINED)
      VALGRIND_MAKE_MEM_UNDEFINED(stack, sizeof(*stack));
  #elif defined(VALGRIND_MAKE_WRITABLE)
      VALGRIND_MAKE_WRITABLE(stack, sizeof(*stack));
  #endif
      stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
      stack->rec_ptr      = &stack->rec;
      stack->context_ptr  = &stack->context;
  
      stack->rec.ExceptionRecord  = NULL;
      stack->rec.ExceptionCode    = exception_code;
      stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
      stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
      stack->rec.NumberParameters = 0;
  
      save_context( &stack->context, sigcontext, fs, gs );
  
      /* now modify the sigcontext to return to the raise function */
      ESP_sig(sigcontext) = (DWORD)stack;
      EIP_sig(sigcontext) = (DWORD)func;
      /* clear single-step, direction, and align check flag */
      EFL_sig(sigcontext) &= ~(0x100|0x400|0x40000);
      CS_sig(sigcontext)  = wine_get_cs();
      DS_sig(sigcontext)  = wine_get_ds();
      ES_sig(sigcontext)  = wine_get_es();
      FS_sig(sigcontext)  = wine_get_fs();
      GS_sig(sigcontext)  = wine_get_gs();
      SS_sig(sigcontext)  = wine_get_ss();
  
      return stack->rec_ptr;
  }
  
  
  /***********************************************************************
   *           setup_exception
   *
   * Setup a proper stack frame for the raise function, and modify the
   * sigcontext so that the return from the signal handler will call
   * the raise function.
   */
  static EXCEPTION_RECORD *setup_exception( ucontext_t *sigcontext, raise_func func )
  {
      WORD fs, gs;
      void *stack = init_handler( sigcontext, &fs, &gs );
  
      return setup_exception_record( sigcontext, stack, fs, gs, func );
  }
  
  
  /***********************************************************************
   *           get_exception_context
   *
   * Get a pointer to the context built by setup_exception.
   */
  static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
  {
      return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
  }
  
  
  /**********************************************************************
   *		get_fpu_code
   *
   * Get the FPU exception code from the FPU status.
   */
  static inline DWORD get_fpu_code( const CONTEXT *context )
  {
      DWORD status = context->FloatSave.StatusWord & ~(context->FloatSave.ControlWord & 0x3f);
  
      if (status & 0x01)  /* IE */
      {
          if (status & 0x40)  /* SF */
              return EXCEPTION_FLT_STACK_CHECK;
          else
              return EXCEPTION_FLT_INVALID_OPERATION;
      }
      if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
      if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
      if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
      if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
      if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
      return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
  }
  
  
  /**********************************************************************
   *		raise_segv_exception
   */
  static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      NTSTATUS status;
  
      switch(rec->ExceptionCode)
      {
      case EXCEPTION_ACCESS_VIOLATION:
          if (rec->NumberParameters == 2)
          {
              if (rec->ExceptionInformation[1] == 0xffffffff && check_invalid_gs( context ))
                  goto done;
              if (!(rec->ExceptionCode = virtual_handle_fault( (void *)rec->ExceptionInformation[1],
                                                               rec->ExceptionInformation[0], FALSE )))
                  goto done;
              if (rec->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
                  rec->ExceptionInformation[0] == EXCEPTION_EXECUTE_FAULT)
              {
                  ULONG flags;
                  NtQueryInformationProcess( GetCurrentProcess(), ProcessExecuteFlags,
                                             &flags, sizeof(flags), NULL );
  
                  if (!(flags & MEM_EXECUTE_OPTION_DISABLE_THUNK_EMULATION) && check_atl_thunk( rec, context ))
                      goto done;
  
                  /* send EXCEPTION_EXECUTE_FAULT only if data execution prevention is enabled */
                  if (!(flags & MEM_EXECUTE_OPTION_DISABLE))
                      rec->ExceptionInformation[0] = EXCEPTION_READ_FAULT;
              }
          }
          break;
      case EXCEPTION_DATATYPE_MISALIGNMENT:
          /* FIXME: pass through exception handler first? */
          if (context->EFlags & 0x00040000)
          {
              /* Disable AC flag, return */
              context->EFlags &= ~0x00040000;
              goto done;
          }
          break;
      case EXCEPTION_BREAKPOINT:
          if (!is_wow64)
          {
              /* On Wow64, the upper DWORD of Rax contains garbage, and the debug
               * service is usually not recognized when called from usermode. */
              switch (rec->ExceptionInformation[0])
              {
                  case 1: /* BREAKPOINT_PRINT */
                  case 3: /* BREAKPOINT_LOAD_SYMBOLS */
                  case 4: /* BREAKPOINT_UNLOAD_SYMBOLS */
                  case 5: /* BREAKPOINT_COMMAND_STRING (>= Win2003) */
                      goto done;
              }
          }
          break;
      }
      status = NtRaiseException( rec, context, TRUE );
      raise_status( status, rec );
  done:
      set_cpu_context( context );
  }
  
  
  /**********************************************************************
   *		raise_trap_exception
   */
  static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      NTSTATUS status;
  
      if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
      {
          /* when single stepping can't tell whether this is a hw bp or a
           * single step interrupt. try to avoid as much overhead as possible
           * and only do a server call if there is any hw bp enabled. */
  
          if( !(context->EFlags & 0x100) || (x86_thread_data()->dr7 & 0xff) )
          {
              /* (possible) hardware breakpoint, fetch the debug registers */
              DWORD saved_flags = context->ContextFlags;
              context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
              NtGetContextThread(GetCurrentThread(), context);
              context->ContextFlags |= saved_flags;  /* restore flags */
          }
  
          context->EFlags &= ~0x100;  /* clear single-step flag */
      }
  
      status = NtRaiseException( rec, context, TRUE );
      raise_status( status, rec );
  }
  
  
  /**********************************************************************
   *		raise_generic_exception
   *
   * Generic raise function for exceptions that don't need special treatment.
   */
  static void WINAPI raise_generic_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      NTSTATUS status;
  
      status = NtRaiseException( rec, context, TRUE );
      raise_status( status, rec );
  }
  
  
  #ifdef __HAVE_VM86
  /**********************************************************************
   *		raise_vm86_sti_exception
   */
  static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
  {
      /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
      get_vm86_teb_info()->vm86_pending |= VIP_FLAG;
  
      if (x86_thread_data()->vm86_ptr)
      {
          if (((char*)context->Eip >= (char*)vm86_return) &&
              ((char*)context->Eip <= (char*)vm86_return_end) &&
              (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
              /* exiting from VM86, can't throw */
              goto done;
          }
          merge_vm86_pending_flags( rec );
      }
      else if (get_vm86_teb_info()->dpmi_vif &&
               !wine_ldt_is_system(context->SegCs) &&
               !wine_ldt_is_system(context->SegSs))
      {
          /* Executing DPMI code and virtual interrupts are enabled. */
          get_vm86_teb_info()->vm86_pending = 0;
          NtRaiseException( rec, context, TRUE );
      }
  done:
      set_cpu_context( context );
  }
  
  
  /**********************************************************************
   *		usr2_handler
   *
   * Handler for SIGUSR2.
   * We use it to signal that the running __wine_enter_vm86() should
   * immediately set VIP_FLAG, causing pending events to be handled
   * as early as possible.
   */
  static void usr2_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_vm86_sti_exception );
      rec->ExceptionCode = EXCEPTION_VM86_STI;
  }
  #endif /* __HAVE_VM86 */
  
  
  /**********************************************************************
   *		segv_handler
   *
   * Handler for SIGSEGV and related errors.
   */
  static void segv_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      WORD fs, gs;
      EXCEPTION_RECORD *rec;
      ucontext_t *context = sigcontext;
      void *stack = init_handler( sigcontext, &fs, &gs );
  
      /* check for exceptions on the signal stack caused by write watches */
      if (get_trap_code(context) == TRAP_x86_PAGEFLT &&
          (char *)stack >= (char *)get_signal_stack() &&
          (char *)stack < (char *)get_signal_stack() + signal_stack_size &&
          !virtual_handle_fault( siginfo->si_addr, (get_error_code(context) >> 1) & 0x09, TRUE ))
      {
          return;
      }
  
      /* check for page fault inside the thread stack */
      if (get_trap_code(context) == TRAP_x86_PAGEFLT &&
          (char *)siginfo->si_addr >= (char *)NtCurrentTeb()->DeallocationStack &&
          (char *)siginfo->si_addr < (char *)NtCurrentTeb()->Tib.StackBase &&
          virtual_handle_stack_fault( siginfo->si_addr ))
      {
          /* check if this was the last guard page */
          if ((char *)siginfo->si_addr < (char *)NtCurrentTeb()->DeallocationStack + 2*4096)
          {
              rec = setup_exception_record( context, stack, fs, gs, raise_segv_exception );
              rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
          }
          return;
      }
  
      rec = setup_exception_record( context, stack, fs, gs, raise_segv_exception );
      if (rec->ExceptionCode == EXCEPTION_STACK_OVERFLOW) return;
  
      switch(get_trap_code(context))
      {
      case TRAP_x86_OFLOW:   /* Overflow exception */
          rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
          break;
      case TRAP_x86_BOUND:   /* Bound range exception */
          rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
          break;
      case TRAP_x86_PRIVINFLT:   /* Invalid opcode exception */
          rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
          break;
      case TRAP_x86_STKFLT:  /* Stack fault */
          rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
          break;
      case TRAP_x86_SEGNPFLT:  /* Segment not present exception */
      case TRAP_x86_PROTFLT:   /* General protection fault */
      case TRAP_x86_UNKNOWN:   /* Unknown fault code */
          {
              CONTEXT *win_context = get_exception_context( rec );
              WORD err = get_error_code(context);
              if (!err && (rec->ExceptionCode = is_privileged_instr( win_context ))) break;
              if ((err & 7) == 2 && handle_interrupt( err >> 3, rec, win_context )) break;
              rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
              rec->NumberParameters = 2;
              rec->ExceptionInformation[0] = 0;
              /* if error contains a LDT selector, use that as fault address */
              if ((err & 7) == 4 && !wine_ldt_is_system( err | 7 ))
                  rec->ExceptionInformation[1] = err & ~7;
              else
                  rec->ExceptionInformation[1] = 0xffffffff;
          }
          break;
      case TRAP_x86_PAGEFLT:  /* Page fault */
          rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
          rec->NumberParameters = 2;
          rec->ExceptionInformation[0] = (get_error_code(context) >> 1) & 0x09;
          rec->ExceptionInformation[1] = (ULONG_PTR)siginfo->si_addr;
          break;
      case TRAP_x86_ALIGNFLT:  /* Alignment check exception */
          rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
          break;
      default:
          WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
          /* fall through */
      case TRAP_x86_NMI:       /* NMI interrupt */
      case TRAP_x86_DNA:       /* Device not available exception */
      case TRAP_x86_DOUBLEFLT: /* Double fault exception */
      case TRAP_x86_TSSFLT:    /* Invalid TSS exception */
      case TRAP_x86_MCHK:      /* Machine check exception */
      case TRAP_x86_CACHEFLT:  /* Cache flush exception */
          rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
          break;
      }
  }
  
  
  /**********************************************************************
   *		trap_handler
   *
   * Handler for SIGTRAP.
   */
  static void trap_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      ucontext_t *context = sigcontext;
      EXCEPTION_RECORD *rec = setup_exception( context, raise_trap_exception );
  
      switch(get_trap_code(context))
      {
      case TRAP_x86_TRCTRAP:  /* Single-step exception */
          rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
          break;
      case TRAP_x86_BPTFLT:   /* Breakpoint exception */
          rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
          /* fall through */
      default:
          rec->ExceptionCode = EXCEPTION_BREAKPOINT;
          rec->NumberParameters = is_wow64 ? 1 : 3;
          rec->ExceptionInformation[0] = 0;
          rec->ExceptionInformation[1] = 0; /* FIXME */
          rec->ExceptionInformation[2] = 0; /* FIXME */
          break;
      }
  }
  
  
  /**********************************************************************
   *		fpe_handler
   *
   * Handler for SIGFPE.
   */
  static void fpe_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      CONTEXT *win_context;
      ucontext_t *context = sigcontext;
      EXCEPTION_RECORD *rec = setup_exception( context, raise_generic_exception );
  
      win_context = get_exception_context( rec );
  
      switch(get_trap_code(context))
      {
      case TRAP_x86_DIVIDE:   /* Division by zero exception */
          rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
          break;
      case TRAP_x86_FPOPFLT:   /* Coprocessor segment overrun */
          rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
          break;
      case TRAP_x86_ARITHTRAP:  /* Floating point exception */
      case TRAP_x86_UNKNOWN:    /* Unknown fault code */
          rec->ExceptionCode = get_fpu_code( win_context );
          rec->ExceptionAddress = (LPVOID)win_context->FloatSave.ErrorOffset;
          break;
      case TRAP_x86_CACHEFLT:  /* SIMD exception */
          /* TODO:
           * Behaviour only tested for divide-by-zero exceptions
           * Check for other SIMD exceptions as well */
          if(siginfo->si_code != FPE_FLTDIV && siginfo->si_code != FPE_FLTINV)
              FIXME("untested SIMD exception: %#x. Might not work correctly\n",
                    siginfo->si_code);
  
          rec->ExceptionCode = STATUS_FLOAT_MULTIPLE_TRAPS;
          rec->NumberParameters = 1;
          /* no idea what meaning is actually behind this but that's what native does */
          rec->ExceptionInformation[0] = 0;
          break;
      default:
          WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
          rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
          break;
      }
  }
  
  
  /**********************************************************************
   *		int_handler
   *
   * Handler for SIGINT.
   *
   * FIXME: should not be calling external functions on the signal stack.
   */
  static void int_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      WORD fs, gs;
      init_handler( sigcontext, &fs, &gs );
      if (!dispatch_signal(SIGINT))
      {
          EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_generic_exception );
          rec->ExceptionCode = CONTROL_C_EXIT;
      }
  }
  
  /**********************************************************************
   *		abrt_handler
   *
   * Handler for SIGABRT.
   */
  static void abrt_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_generic_exception );
      rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
      rec->ExceptionFlags = EH_NONCONTINUABLE;
  }
  
  
  /**********************************************************************
   *		quit_handler
   *
   * Handler for SIGQUIT.
   */
  static void quit_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      WORD fs, gs;
      init_handler( sigcontext, &fs, &gs );
      abort_thread(0);
  }
  
  
  /**********************************************************************
   *		usr1_handler
   *
   * Handler for SIGUSR1, used to signal a thread that it got suspended.
   */
  static void usr1_handler( int signal, siginfo_t *siginfo, void *sigcontext )
  {
      CONTEXT context;
      WORD fs, gs;
  
      init_handler( sigcontext, &fs, &gs );
      save_context( &context, sigcontext, fs, gs );
      wait_suspend( &context );
      restore_context( &context, sigcontext );
  }
  
  
  /***********************************************************************
   *           __wine_set_signal_handler   (NTDLL.@)
   */
  int CDECL __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
  {
      if (sig >= sizeof(handlers) / sizeof(handlers[0])) return -1;
      if (handlers[sig] != NULL) return -2;
      handlers[sig] = wsh;
      return 0;
  }
  
  
  /***********************************************************************
   *           locking for LDT routines
   */
  static RTL_CRITICAL_SECTION ldt_section;
  static RTL_CRITICAL_SECTION_DEBUG critsect_debug =
  {
      0, 0, &ldt_section,
      { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
        0, 0, { (DWORD_PTR)(__FILE__ ": ldt_section") }
  };
  static RTL_CRITICAL_SECTION ldt_section = { &critsect_debug, -1, 0, 0, 0, 0 };
  static sigset_t ldt_sigset;
  
  static void ldt_lock(void)
  {
      sigset_t sigset;
  
      pthread_sigmask( SIG_BLOCK, &server_block_set, &sigset );
      RtlEnterCriticalSection( &ldt_section );
      if (ldt_section.RecursionCount == 1) ldt_sigset = sigset;
  }
  
  static void ldt_unlock(void)
  {
      if (ldt_section.RecursionCount == 1)
      {
          sigset_t sigset = ldt_sigset;
          RtlLeaveCriticalSection( &ldt_section );
          pthread_sigmask( SIG_SETMASK, &sigset, NULL );
      }
      else RtlLeaveCriticalSection( &ldt_section );
  }
  
  
  /**********************************************************************
   *		signal_alloc_thread
   */
  NTSTATUS signal_alloc_thread( TEB **teb )
  {
      static size_t sigstack_zero_bits;
      struct x86_thread_data *thread_data;
      SIZE_T size;
      void *addr = NULL;
      NTSTATUS status;
  
      if (!sigstack_zero_bits)
      {
          size_t min_size = teb_size + max( MINSIGSTKSZ, 8192 );
          /* find the first power of two not smaller than min_size */
          sigstack_zero_bits = 12;
          while ((1u << sigstack_zero_bits) < min_size) sigstack_zero_bits++;
          signal_stack_mask = (1 << sigstack_zero_bits) - 1;
          signal_stack_size = (1 << sigstack_zero_bits) - teb_size;
      }
  
      size = signal_stack_mask + 1;
      if (!(status = NtAllocateVirtualMemory( NtCurrentProcess(), &addr, sigstack_zero_bits,
                                              &size, MEM_COMMIT | MEM_TOP_DOWN, PAGE_READWRITE )))
      {
          *teb = addr;
          (*teb)->Tib.Self = &(*teb)->Tib;
          (*teb)->Tib.ExceptionList = (void *)~0UL;
          thread_data = (struct x86_thread_data *)(*teb)->SystemReserved2;
          if (!(thread_data->fs = wine_ldt_alloc_fs()))
          {
              size = 0;
              NtFreeVirtualMemory( NtCurrentProcess(), &addr, &size, MEM_RELEASE );
              status = STATUS_TOO_MANY_THREADS;
          }
      }
      return status;
  }
  
  
  /**********************************************************************
   *		signal_free_thread
   */
  void signal_free_thread( TEB *teb )
  {
      SIZE_T size = 0;
      struct x86_thread_data *thread_data = (struct x86_thread_data *)teb->SystemReserved2;
  
      wine_ldt_free_fs( thread_data->fs );
      NtFreeVirtualMemory( NtCurrentProcess(), (void **)&teb, &size, MEM_RELEASE );
  }
  
  
  /**********************************************************************
   *		signal_init_thread
   */
  void signal_init_thread( TEB *teb )
  {
      const WORD fpu_cw = 0x27f;
      struct x86_thread_data *thread_data = (struct x86_thread_data *)teb->SystemReserved2;
      LDT_ENTRY fs_entry;
      stack_t ss;
  
  #ifdef __APPLE__
      int mib[2], val = 1;
  
      mib[0] = CTL_KERN;
      mib[1] = KERN_THALTSTACK;
      sysctl( mib, 2, NULL, NULL, &val, sizeof(val) );
  #endif
  
      ss.ss_sp    = (char *)teb + teb_size;
      ss.ss_size  = signal_stack_size;
      ss.ss_flags = 0;
      if (sigaltstack(&ss, NULL) == -1) perror( "sigaltstack" );
  
      wine_ldt_set_base( &fs_entry, teb );
      wine_ldt_set_limit( &fs_entry, teb_size - 1 );
      wine_ldt_set_flags( &fs_entry, WINE_LDT_FLAGS_DATA|WINE_LDT_FLAGS_32BIT );
      wine_ldt_init_fs( thread_data->fs, &fs_entry );
      thread_data->gs = wine_get_gs();
  
  #ifdef __GNUC__
      __asm__ volatile ("fninit; fldcw %0" : : "m" (fpu_cw));
  #else
      FIXME("FPU setup not implemented for this platform.\n");
  #endif
  }
  
  /**********************************************************************
   *		signal_init_process
   */
  void signal_init_process(void)
  {
      struct sigaction sig_act;
  
      sig_act.sa_mask = server_block_set;
      sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
  #ifdef SA_ONSTACK
      sig_act.sa_flags |= SA_ONSTACK;
  #endif
  #ifdef __ANDROID__
      sig_act.sa_flags |= SA_RESTORER;
      sig_act.sa_restorer = rt_sigreturn;
  #endif
      sig_act.sa_sigaction = int_handler;
      if (sigaction( SIGINT, &sig_act, NULL ) == -1) goto error;
      sig_act.sa_sigaction = fpe_handler;
      if (sigaction( SIGFPE, &sig_act, NULL ) == -1) goto error;
      sig_act.sa_sigaction = abrt_handler;
      if (sigaction( SIGABRT, &sig_act, NULL ) == -1) goto error;
      sig_act.sa_sigaction = quit_handler;
      if (sigaction( SIGQUIT, &sig_act, NULL ) == -1) goto error;
      sig_act.sa_sigaction = usr1_handler;
      if (sigaction( SIGUSR1, &sig_act, NULL ) == -1) goto error;
  
      sig_act.sa_sigaction = segv_handler;
      if (sigaction( SIGSEGV, &sig_act, NULL ) == -1) goto error;
      if (sigaction( SIGILL, &sig_act, NULL ) == -1) goto error;
  #ifdef SIGBUS
      if (sigaction( SIGBUS, &sig_act, NULL ) == -1) goto error;
  #endif
  
  #ifdef SIGTRAP
      sig_act.sa_sigaction = trap_handler;
      if (sigaction( SIGTRAP, &sig_act, NULL ) == -1) goto error;
  #endif
  
  #ifdef __HAVE_VM86
      sig_act.sa_sigaction = usr2_handler;
      if (sigaction( SIGUSR2, &sig_act, NULL ) == -1) goto error;
  #endif
  
      wine_ldt_init_locking( ldt_lock, ldt_unlock );
      return;
  
   error:
      perror("sigaction");
      exit(1);
  }
  
  
  
  #ifdef __HAVE_VM86
  /**********************************************************************
   *		__wine_enter_vm86   (NTDLL.@)
   *
   * Enter vm86 mode with the specified register context.
   */
  void __wine_enter_vm86( CONTEXT *context )
  {
      EXCEPTION_RECORD rec;
      int res;
      struct vm86plus_struct vm86;
  
      memset( &vm86, 0, sizeof(vm86) );
      for (;;)
      {
          restore_vm86_context( context, &vm86 );
  
          x86_thread_data()->vm86_ptr = &vm86;
          merge_vm86_pending_flags( &rec );
  
          res = vm86_enter( &x86_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
          if (res < 0)
          {
              errno = -res;
              return;
          }
  
          save_vm86_context( context, &vm86 );
  
          rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
          rec.ExceptionRecord  = NULL;
          rec.ExceptionAddress = (LPVOID)context->Eip;
          rec.NumberParameters = 0;
  
          switch(VM86_TYPE(res))
          {
          case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
              rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
              break;
          case VM86_TRAP: /* return due to DOS-debugger request */
              switch(VM86_ARG(res))
              {
              case TRAP_x86_TRCTRAP:  /* Single-step exception */
                  rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
                  break;
              case TRAP_x86_BPTFLT:   /* Breakpoint exception */
                  rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
                  /* fall through */
              default:
                  rec.ExceptionCode = EXCEPTION_BREAKPOINT;
                  break;
              }
              break;
          case VM86_INTx: /* int3/int x instruction (ARG = x) */
              rec.ExceptionCode = EXCEPTION_VM86_INTx;
              rec.NumberParameters = 1;
              rec.ExceptionInformation[0] = VM86_ARG(res);
              break;
          case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
              context->EFlags |= VIF_FLAG;
              context->EFlags &= ~VIP_FLAG;
              get_vm86_teb_info()->vm86_pending = 0;
              rec.ExceptionCode = EXCEPTION_VM86_STI;
              break;
          case VM86_PICRETURN: /* return due to pending PIC request */
              rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
              break;
          case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
          default:
              WINE_ERR( "unhandled result from vm86 mode %x\n", res );
              continue;
          }
          raise_exception( &rec, context, TRUE );
      }
  }
  
  #else /* __HAVE_VM86 */
  /**********************************************************************
   *		__wine_enter_vm86   (NTDLL.@)
   */
  void __wine_enter_vm86( CONTEXT *context )
  {
      MESSAGE("vm86 mode not supported on this platform\n");
  }
  #endif /* __HAVE_VM86 */
  
  
  /*******************************************************************
   *		RtlUnwind (NTDLL.@)
   */
  void WINAPI DECLSPEC_HIDDEN __regs_RtlUnwind( EXCEPTION_REGISTRATION_RECORD* pEndFrame, PVOID targetIp,
                                                PEXCEPTION_RECORD pRecord, PVOID retval, CONTEXT *context )
  {
      EXCEPTION_RECORD record;
      EXCEPTION_REGISTRATION_RECORD *frame, *dispatch;
      DWORD res;
  
      context->Eax = (DWORD)retval;
  
      /* build an exception record, if we do not have one */
      if (!pRecord)
      {
          record.ExceptionCode    = STATUS_UNWIND;
          record.ExceptionFlags   = 0;
          record.ExceptionRecord  = NULL;
          record.ExceptionAddress = (void *)context->Eip;
          record.NumberParameters = 0;
          pRecord = &record;
      }
  
      pRecord->ExceptionFlags |= EH_UNWINDING | (pEndFrame ? 0 : EH_EXIT_UNWIND);
  
      TRACE( "code=%x flags=%x\n", pRecord->ExceptionCode, pRecord->ExceptionFlags );
      TRACE( "eax=%08x ebx=%08x ecx=%08x edx=%08x esi=%08x edi=%08x\n",
             context->Eax, context->Ebx, context->Ecx, context->Edx, context->Esi, context->Edi );
      TRACE( "ebp=%08x esp=%08x eip=%08x cs=%04x ds=%04x fs=%04x gs=%04x flags=%08x\n",
             context->Ebp, context->Esp, context->Eip, LOWORD(context->SegCs), LOWORD(context->SegDs),
             LOWORD(context->SegFs), LOWORD(context->SegGs), context->EFlags );
  
      /* get chain of exception frames */
      frame = NtCurrentTeb()->Tib.ExceptionList;
      while ((frame != (EXCEPTION_REGISTRATION_RECORD*)~0UL) && (frame != pEndFrame))
      {
          /* Check frame address */
          if (pEndFrame && (frame > pEndFrame))
              raise_status( STATUS_INVALID_UNWIND_TARGET, pRecord );
  
          if (!is_valid_frame( frame )) raise_status( STATUS_BAD_STACK, pRecord );
  
          /* Call handler */
          TRACE( "calling handler at %p code=%x flags=%x\n",
                 frame->Handler, pRecord->ExceptionCode, pRecord->ExceptionFlags );
          res = EXC_CallHandler( pRecord, frame, context, &dispatch, frame->Handler, unwind_handler );
          TRACE( "handler at %p returned %x\n", frame->Handler, res );
  
          switch(res)
          {
          case ExceptionContinueSearch:
              break;
          case ExceptionCollidedUnwind:
              frame = dispatch;
              break;
          default:
              raise_status( STATUS_INVALID_DISPOSITION, pRecord );
              break;
          }
          frame = __wine_pop_frame( frame );
      }
  
      NtSetContextThread( GetCurrentThread(), context );
  }
  __ASM_STDCALL_FUNC( RtlUnwind, 16,
                      "pushl %ebp\n\t"
                      __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                      __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                      "movl %esp,%ebp\n\t"
                      __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                      "leal -(0x2cc+8)(%esp),%esp\n\t" /* sizeof(CONTEXT) + alignment */
                      "pushl %esp\n\t"                 /* context */
                      "call " __ASM_NAME("RtlCaptureContext") __ASM_STDCALL(4) "\n\t"
                      "leal 24(%ebp),%eax\n\t"
                      "movl %eax,0xc4(%esp)\n\t"       /* context->Esp */
                      "pushl %esp\n\t"
                      "pushl 20(%ebp)\n\t"
                      "pushl 16(%ebp)\n\t"
                      "pushl 12(%ebp)\n\t"
                      "pushl 8(%ebp)\n\t"
                      "call " __ASM_NAME("__regs_RtlUnwind") __ASM_STDCALL(20) "\n\t"
                      "leave\n\t"
                      __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                      __ASM_CFI(".cfi_same_value %ebp\n\t")
                      "ret $16" )  /* actually never returns */
  
  
  /*******************************************************************
   *		NtRaiseException (NTDLL.@)
   */
  NTSTATUS WINAPI NtRaiseException( EXCEPTION_RECORD *rec, CONTEXT *context, BOOL first_chance )
  {
      NTSTATUS status = raise_exception( rec, context, first_chance );
      if (status == STATUS_SUCCESS) NtSetContextThread( GetCurrentThread(), context );
      return status;
  }
  
  
  /***********************************************************************
   *		RtlRaiseException (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( RtlRaiseException, 4,
                      "pushl %ebp\n\t"
                      __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                      __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                      "movl %esp,%ebp\n\t"
                      __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                      "leal -0x2cc(%esp),%esp\n\t"  /* sizeof(CONTEXT) */
                      "pushl %esp\n\t"              /* context */
                      "call " __ASM_NAME("RtlCaptureContext") __ASM_STDCALL(4) "\n\t"
                      "movl 4(%ebp),%eax\n\t"       /* return address */
                      "movl 8(%ebp),%ecx\n\t"       /* rec */
                      "movl %eax,12(%ecx)\n\t"      /* rec->ExceptionAddress */
                      "leal 12(%ebp),%eax\n\t"
                      "movl %eax,0xc4(%esp)\n\t"    /* context->Esp */
                      "movl %esp,%eax\n\t"
                      "pushl $1\n\t"
                      "pushl %eax\n\t"
                      "pushl %ecx\n\t"
                      "call " __ASM_NAME("NtRaiseException") __ASM_STDCALL(12) "\n\t"
                      "pushl %eax\n\t"
                      "call " __ASM_NAME("RtlRaiseStatus") __ASM_STDCALL(4) "\n\t"
                      "leave\n\t"
                      __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                      __ASM_CFI(".cfi_same_value %ebp\n\t")
                      "ret $4" )  /* actually never returns */
  
  
  /*************************************************************************
   *		RtlCaptureStackBackTrace (NTDLL.@)
   */
  USHORT WINAPI RtlCaptureStackBackTrace( ULONG skip, ULONG count, PVOID *buffer, ULONG *hash )
  {
      CONTEXT context;
      ULONG i;
      ULONG *frame;
  
      RtlCaptureContext( &context );
      if (hash) *hash = 0;
      frame = (ULONG *)context.Ebp;
  
      while (skip--)
      {
          if (!is_valid_frame( frame )) return 0;
          frame = (ULONG *)*frame;
      }
  
      for (i = 0; i < count; i++)
      {
          if (!is_valid_frame( frame )) break;
          buffer[i] = (void *)frame[1];
          if (hash) *hash += frame[1];
          frame = (ULONG *)*frame;
      }
      return i;
  }
  
  
  extern void DECLSPEC_NORETURN start_thread( LPTHREAD_START_ROUTINE entry, void *arg, BOOL suspend,
                                              void *relay, void **exit_frame );
  __ASM_GLOBAL_FUNC( start_thread,
                     "pushl %ebp\n\t"
                     __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                     __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                     "movl %esp,%ebp\n\t"
                     __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                     "pushl %ebx\n\t"
                     __ASM_CFI(".cfi_rel_offset %ebx,-4\n\t")
                     "pushl %esi\n\t"
                     __ASM_CFI(".cfi_rel_offset %esi,-8\n\t")
                     "pushl %edi\n\t"
                     __ASM_CFI(".cfi_rel_offset %edi,-12\n\t")
                     /* store exit frame */
                     "movl 24(%ebp),%eax\n\t"
                     "movl %ebp,(%eax)\n\t"
                     /* build initial context on thread stack */
                     "movl %fs:4,%eax\n\t"        /* NtCurrentTeb()->StackBase */
                     "leal -0x2dc(%eax),%esi\n\t" /* sizeof(context) + 16 */
                     "movl $0x10007,(%esi)\n\t"   /* context->ContextFlags = CONTEXT_FULL */
                     "movw %cs,0xbc(%esi)\n\t"    /* context->SegCs */
                     "movw %ds,0x98(%esi)\n\t"    /* context->SegDs */
                     "movw %es,0x94(%esi)\n\t"    /* context->SegEs */
                     "movw %fs,0x90(%esi)\n\t"    /* context->SegFs */
                     "movw %gs,0x8c(%esi)\n\t"    /* context->SegGs */
                     "movw %ss,0xc8(%esi)\n\t"    /* context->SegSs */
                     "movl 8(%ebp),%eax\n\t"
                     "movl %eax,0xb0(%esi)\n\t"   /* context->Eax = entry */
                     "movl 12(%ebp),%eax\n\t"
                     "movl %eax,0xa4(%esi)\n\t"   /* context->Ebx = arg */
                     "movl 20(%ebp),%eax\n\t"
                     "movl %eax,0xb8(%esi)\n\t"   /* context->Eip = relay */
                     "leal 0x2cc(%esi),%eax\n\t"
                     "movl %eax,0xc4(%esi)\n\t"   /* context->Esp */
                     /* switch to thread stack */
                     "leal -12(%esi),%esp\n\t"
                     /* attach dlls */
                     "pushl 16(%ebp)\n\t"         /* suspend */
                     "pushl %esi\n\t"             /* context */
                     "xorl %ebp,%ebp\n\t"
                     "call " __ASM_NAME("attach_dlls") "\n\t"
                     "addl $20,%esp\n\t"
                     /* clear the stack */
                     "leal -0xd24(%esi),%eax\n\t"  /* round down to page size */
                     "pushl %eax\n\t"
                     "call " __ASM_NAME("virtual_clear_thread_stack") "\n\t"
                     /* switch to the initial context */
                     "movl %esi,(%esp)\n\t"
                     "call " __ASM_NAME("set_cpu_context") )
  
  extern void DECLSPEC_NORETURN call_thread_exit_func( int status, void (*func)(int), void *frame );
  __ASM_GLOBAL_FUNC( call_thread_exit_func,
                     "movl 4(%esp),%eax\n\t"
                     "movl 8(%esp),%ecx\n\t"
                     "movl 12(%esp),%ebp\n\t"
                     __ASM_CFI(".cfi_def_cfa %ebp,4\n\t")
                     __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                     __ASM_CFI(".cfi_rel_offset %ebx,-4\n\t")
                     __ASM_CFI(".cfi_rel_offset %esi,-8\n\t")
                     __ASM_CFI(".cfi_rel_offset %edi,-12\n\t")
                     "leal -20(%ebp),%esp\n\t"
                     "pushl %eax\n\t"
                     "call *%ecx" );
  
  extern void call_thread_entry(void) DECLSPEC_HIDDEN;
  __ASM_GLOBAL_FUNC( call_thread_entry,
                     "pushl %ebp\n\t"
                     __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                     __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                     "movl %esp,%ebp\n\t"
                     __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                     "pushl %ebx\n\t"  /* arg */
                     "pushl %eax\n\t"  /* entry */
                     "call " __ASM_NAME("call_thread_func") )
  
  /* wrapper for apps that don't declare the thread function correctly */
  extern DWORD call_thread_func_wrapper( LPTHREAD_START_ROUTINE entry, void *arg );
  __ASM_GLOBAL_FUNC(call_thread_func_wrapper,
                    "pushl %ebp\n\t"
                    __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                    __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                    "movl %esp,%ebp\n\t"
                    __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                    "subl $4,%esp\n\t"
                    "pushl 12(%ebp)\n\t"
                    "call *8(%ebp)\n\t"
                    "leave\n\t"
                    __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                    __ASM_CFI(".cfi_same_value %ebp\n\t")
                    "ret" )
  
  /***********************************************************************
   *           call_thread_func
   */
  void DECLSPEC_HIDDEN call_thread_func( LPTHREAD_START_ROUTINE entry, void *arg )
  {
      __TRY
      {
          TRACE_(relay)( "\1Starting thread proc %p (arg=%p)\n", entry, arg );
          RtlExitUserThread( call_thread_func_wrapper( entry, arg ));
      }
      __EXCEPT(unhandled_exception_filter)
      {
          NtTerminateThread( GetCurrentThread(), GetExceptionCode() );
      }
      __ENDTRY
      abort();  /* should not be reached */
  }
  
  
  /***********************************************************************
   *           signal_start_thread
   *
   * Thread startup sequence:
   * signal_start_thread()
   *   -> start_thread()
   *     -> call_thread_entry()
   *       -> call_thread_func()
   */
  void signal_start_thread( LPTHREAD_START_ROUTINE entry, void *arg, BOOL suspend )
  {
      start_thread( entry, arg, suspend, call_thread_entry, &x86_thread_data()->exit_frame );
  }
  
  /**********************************************************************
   *		signal_start_process
   *
   * Process startup sequence:
   * signal_start_process()
   *   -> start_thread()
   *     -> kernel32_start_process()
   */
  void signal_start_process( LPTHREAD_START_ROUTINE entry, BOOL suspend )
  {
      start_thread( entry, NtCurrentTeb()->Peb, suspend,
                    kernel32_start_process, &x86_thread_data()->exit_frame );
  }
  
  
  /***********************************************************************
   *           RtlExitUserThread  (NTDLL.@)
   */
  void WINAPI RtlExitUserThread( ULONG status )
  {
      if (!x86_thread_data()->exit_frame) exit_thread( status );
      call_thread_exit_func( status, exit_thread, x86_thread_data()->exit_frame );
  }
  
  /***********************************************************************
   *           abort_thread
   */
  void abort_thread( int status )
  {
      if (!x86_thread_data()->exit_frame) terminate_thread( status );
      call_thread_exit_func( status, terminate_thread, x86_thread_data()->exit_frame );
  }
  
  /**********************************************************************
   *		DbgBreakPoint   (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( DbgBreakPoint, 0, "int $3; ret")
  
  /**********************************************************************
   *		DbgUserBreakPoint   (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( DbgUserBreakPoint, 0, "int $3; ret")
  
  /**********************************************************************
   *           NtCurrentTeb   (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( NtCurrentTeb, 0, ".byte 0x64\n\tmovl 0x18,%eax\n\tret" )
  
  
  /**************************************************************************
   *           _chkstk   (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( _chkstk, 0,
                     "negl %eax\n\t"
                     "addl %esp,%eax\n\t"
                     "xchgl %esp,%eax\n\t"
                     "movl 0(%eax),%eax\n\t"  /* copy return address from old location */
                     "movl %eax,0(%esp)\n\t"
                     "ret" )
  
  /**************************************************************************
   *           _alloca_probe   (NTDLL.@)
   */
  __ASM_STDCALL_FUNC( _alloca_probe, 0,
                     "negl %eax\n\t"
                     "addl %esp,%eax\n\t"
                     "xchgl %esp,%eax\n\t"
                     "movl 0(%eax),%eax\n\t"  /* copy return address from old location */
                     "movl %eax,0(%esp)\n\t"
                     "ret" )
  
  
  /**********************************************************************
   *		EXC_CallHandler   (internal)
   *
   * Some exception handlers depend on EBP to have a fixed position relative to
   * the exception frame.
   * Shrinker depends on (*1) doing what it does,
   * (*2) being the exact instruction it is and (*3) beginning with 0x64
   * (i.e. the %fs prefix to the movl instruction). It also depends on the
   * function calling the handler having only 5 parameters (*4).
   */
  __ASM_GLOBAL_FUNC( EXC_CallHandler,
                    "pushl %ebp\n\t"
                    __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                    __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                    "movl %esp,%ebp\n\t"
                    __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                     "pushl %ebx\n\t"
                     __ASM_CFI(".cfi_rel_offset %ebx,-4\n\t")
                     "movl 28(%ebp), %edx\n\t" /* ugly hack to pass the 6th param needed because of Shrinker */
                     "pushl 24(%ebp)\n\t"
                     "pushl 20(%ebp)\n\t"
                     "pushl 16(%ebp)\n\t"
                     "pushl 12(%ebp)\n\t"
                     "pushl 8(%ebp)\n\t"
                     "call " __ASM_NAME("call_exception_handler") "\n\t"
                     "popl %ebx\n\t"
                     __ASM_CFI(".cfi_same_value %ebx\n\t")
                     "leave\n"
                     __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                     __ASM_CFI(".cfi_same_value %ebp\n\t")
                     "ret" )
  __ASM_GLOBAL_FUNC(call_exception_handler,
                    "pushl %ebp\n\t"
                    __ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
                    __ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
                    "movl %esp,%ebp\n\t"
                    __ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
                    "subl $12,%esp\n\t"
                    "pushl 12(%ebp)\n\t"      /* make any exceptions in this... */
                    "pushl %edx\n\t"          /* handler be handled by... */
                    ".byte 0x64\n\t"
                    "pushl (0)\n\t"           /* nested_handler (passed in edx). */
                    ".byte 0x64\n\t"
                    "movl %esp,(0)\n\t"       /* push the new exception frame onto the exception stack. */
                    "pushl 20(%ebp)\n\t"
                    "pushl 16(%ebp)\n\t"
                    "pushl 12(%ebp)\n\t"
                    "pushl 8(%ebp)\n\t"
                    "movl 24(%ebp), %ecx\n\t" /* (*1) */
                    "call *%ecx\n\t"          /* call handler. (*2) */
                    ".byte 0x64\n\t"
                    "movl (0), %esp\n\t"      /* restore previous... (*3) */
                    ".byte 0x64\n\t"
                    "popl (0)\n\t"            /* exception frame. */
                    "movl %ebp, %esp\n\t"     /* restore saved stack, in case it was corrupted */
                    "popl %ebp\n\t"
                     __ASM_CFI(".cfi_def_cfa %esp,4\n\t")
                     __ASM_CFI(".cfi_same_value %ebp\n\t")
                    "ret $20" )            /* (*4) */
  
  #endif  /* __i386__ */
  