dlls/ntdll/signal_i386.c

   1 /*
   2  * i386 signal handling routines
   3  *
   4  * Copyright 1999 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #ifdef __i386__
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdlib.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #include <sys/types.h>
  32 #ifdef HAVE_UNISTD_H
  33 # include <unistd.h>
  34 #endif
  35
  36 #ifdef HAVE_SYS_PARAM_H
  37 # include <sys/param.h>
  38 #endif
  39 #ifdef HAVE_SYSCALL_H
  40 # include <syscall.h>
  41 #else
  42 # ifdef HAVE_SYS_SYSCALL_H
  43 #  include <sys/syscall.h>
  44 # endif
  45 #endif
  46
  47 #ifdef HAVE_SYS_VM86_H
  48 # include <sys/vm86.h>
  49 #endif
  50
  51 #ifdef HAVE_SYS_SIGNAL_H
  52 # include <sys/signal.h>
  53 #endif
  54 #ifdef HAVE_SYS_SYSCTL_H
  55 # include <sys/sysctl.h>
  56 #endif
  57
  58 #include "windef.h"
  59 #include "wine/library.h"
  60 #include "ntdll_misc.h"
  61 #include "wine/exception.h"
  62 #include "wine/debug.h"
  63
  64 #ifdef HAVE_VALGRIND_MEMCHECK_H
  65 #include <valgrind/memcheck.h>
  66 #endif
  67
  68 #undef ERR  /* Solaris needs to define this */
  69
  70 /* not defined for x86, so copy the x86_64 definition */
  71 typedef struct DECLSPEC_ALIGN(16) _M128A
  72 {
  73     ULONGLONG Low;
  74     LONGLONG High;
  75 } M128A;
  76
  77 typedef struct
  78 {
  79     WORD ControlWord;
  80     WORD StatusWord;
  81     BYTE TagWord;
  82     BYTE Reserved1;
  83     WORD ErrorOpcode;
  84     DWORD ErrorOffset;
  85     WORD ErrorSelector;
  86     WORD Reserved2;
  87     DWORD DataOffset;
  88     WORD DataSelector;
  89     WORD Reserved3;
  90     DWORD MxCsr;
  91     DWORD MxCsr_Mask;
  92     M128A FloatRegisters[8];
  93     M128A XmmRegisters[16];
  94     BYTE Reserved4[96];
  95 } XMM_SAVE_AREA32;
  96
  97 /***********************************************************************
  98  * signal context platform-specific definitions
  99  */
 100
 101 #ifdef linux
 102
 103 typedef ucontext_t SIGCONTEXT;
 104
 105 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[REG_EAX])
 106 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[REG_EBX])
 107 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[REG_ECX])
 108 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[REG_EDX])
 109 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[REG_ESI])
 110 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[REG_EDI])
 111 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[REG_EBP])
 112 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[REG_ESP])
 113
 114 #define CS_sig(context)      ((context)->uc_mcontext.gregs[REG_CS])
 115 #define DS_sig(context)      ((context)->uc_mcontext.gregs[REG_DS])
 116 #define ES_sig(context)      ((context)->uc_mcontext.gregs[REG_ES])
 117 #define SS_sig(context)      ((context)->uc_mcontext.gregs[REG_SS])
 118 #define FS_sig(context)      ((context)->uc_mcontext.gregs[REG_FS])
 119 #define GS_sig(context)      ((context)->uc_mcontext.gregs[REG_GS])
 120
 121 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[REG_EFL])
 122 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
 123 #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
 124 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
 125
 126 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->uc_mcontext.fpregs))
 127 #define FPUX_sig(context)    (FPU_sig(context) && !((context)->uc_mcontext.fpregs->status >> 16) ? (XMM_SAVE_AREA32 *)(FPU_sig(context) + 1) : NULL)
 128
 129 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 130
 131 int vm86_enter( void **vm86_ptr );
 132 void vm86_return(void);
 133 void vm86_return_end(void);
 134 __ASM_GLOBAL_FUNC(vm86_enter,
 135                   "pushl %ebp\n\t"
 136                   "movl %esp, %ebp\n\t"
 137                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 138                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 139                   "movl (%ecx),%ecx\n\t"
 140                   "pushl %ebx\n\t"
 141                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 142                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 143                   "pushl %fs\n\t"
 144                   "pushl %gs\n\t"
 145                   "int $0x80\n"
 146                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 147                   __ASM_FUNC("vm86_return") "\n"
 148                   __ASM_NAME("vm86_return") ":\n\t"
 149                   "popl %gs\n\t"
 150                   "popl %fs\n\t"
 151                   "popl %ecx\n\t"
 152                   "popl %ebx\n\t"
 153                   "popl %ebp\n\t"
 154                   "testl %eax,%eax\n\t"
 155                   "jl 0f\n\t"
 156                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 157                   "je " __ASM_NAME("vm86_enter") "\n\t"
 158                   "0:\n\t"
 159                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 160                   "movl $0,(%ecx)\n\t"
 161                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 162                   __ASM_FUNC("vm86_return_end") "\n"
 163                   __ASM_NAME("vm86_return_end") ":\n\t"
 164                   "ret" )
 165
 166 #ifdef HAVE_SYS_VM86_H
 167 # define __HAVE_VM86
 168 #endif
 169
 170 #endif  /* linux */
 171
 172 #ifdef BSDI
 173
 174 #include <machine/frame.h>
 175 typedef struct trapframe SIGCONTEXT;
 176
 177 #define EAX_sig(context)     ((context)->tf_eax)
 178 #define EBX_sig(context)     ((context)->tf_ebx)
 179 #define ECX_sig(context)     ((context)->tf_ecx)
 180 #define EDX_sig(context)     ((context)->tf_edx)
 181 #define ESI_sig(context)     ((context)->tf_esi)
 182 #define EDI_sig(context)     ((context)->tf_edi)
 183 #define EBP_sig(context)     ((context)->tf_ebp)
 184
 185 #define CS_sig(context)      ((context)->tf_cs)
 186 #define DS_sig(context)      ((context)->tf_ds)
 187 #define ES_sig(context)      ((context)->tf_es)
 188 #define SS_sig(context)      ((context)->tf_ss)
 189
 190 #define EFL_sig(context)     ((context)->tf_eflags)
 191
 192 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 193 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 194
 195 #define FPU_sig(context)     NULL  /* FIXME */
 196 #define FPUX_sig(context)    NULL  /* FIXME */
 197
 198 #endif /* bsdi */
 199
 200 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 201
 202 typedef struct sigcontext SIGCONTEXT;
 203
 204 #define EAX_sig(context)     ((context)->sc_eax)
 205 #define EBX_sig(context)     ((context)->sc_ebx)
 206 #define ECX_sig(context)     ((context)->sc_ecx)
 207 #define EDX_sig(context)     ((context)->sc_edx)
 208 #define ESI_sig(context)     ((context)->sc_esi)
 209 #define EDI_sig(context)     ((context)->sc_edi)
 210 #define EBP_sig(context)     ((context)->sc_ebp)
 211
 212 #define CS_sig(context)      ((context)->sc_cs)
 213 #define DS_sig(context)      ((context)->sc_ds)
 214 #define ES_sig(context)      ((context)->sc_es)
 215 #define FS_sig(context)      ((context)->sc_fs)
 216 #define GS_sig(context)      ((context)->sc_gs)
 217 #define SS_sig(context)      ((context)->sc_ss)
 218
 219 #define TRAP_sig(context)    ((context)->sc_trapno)
 220 #define ERROR_sig(context)   ((context)->sc_err)
 221 #define EFL_sig(context)     ((context)->sc_eflags)
 222
 223 #define EIP_sig(context)     ((context)->sc_eip)
 224 #define ESP_sig(context)     ((context)->sc_esp)
 225
 226 #define FPU_sig(context)     NULL  /* FIXME */
 227 #define FPUX_sig(context)    NULL  /* FIXME */
 228
 229 #endif  /* *BSD */
 230
 231 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 232
 233 #ifdef _SCO_DS
 234 #include <sys/regset.h>
 235 #endif
 236 #include <sys/ucontext.h>
 237 typedef struct ucontext SIGCONTEXT;
 238
 239 #ifdef _SCO_DS
 240 #define gregs regs
 241 #endif
 242
 243 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 244 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 245 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 246 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 247 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 248 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 249 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 250
 251 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 252 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 253 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 254 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 255
 256 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 257 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 258
 259 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 260
 261 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 262 #ifdef UESP
 263 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 264 #elif defined(R_ESP)
 265 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 266 #else
 267 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 268 #endif
 269 #ifdef ERR
 270 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[ERR])
 271 #endif
 272 #ifdef TRAPNO
 273 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 274 #endif
 275
 276 #define FPU_sig(context)     NULL  /* FIXME */
 277 #define FPUX_sig(context)    NULL  /* FIXME */
 278
 279 #endif  /* svr4 || SCO_DS */
 280
 281 #ifdef __APPLE__
 282 # include <sys/ucontext.h>
 283
 284 typedef ucontext_t SIGCONTEXT;
 285
 286 /* work around silly renaming of struct members in OS X 10.5 */
 287 #if __DARWIN_UNIX03 && defined(_STRUCT_X86_EXCEPTION_STATE32)
 288 #define EAX_sig(context)     ((context)->uc_mcontext->__ss.__eax)
 289 #define EBX_sig(context)     ((context)->uc_mcontext->__ss.__ebx)
 290 #define ECX_sig(context)     ((context)->uc_mcontext->__ss.__ecx)
 291 #define EDX_sig(context)     ((context)->uc_mcontext->__ss.__edx)
 292 #define ESI_sig(context)     ((context)->uc_mcontext->__ss.__esi)
 293 #define EDI_sig(context)     ((context)->uc_mcontext->__ss.__edi)
 294 #define EBP_sig(context)     ((context)->uc_mcontext->__ss.__ebp)
 295 #define CS_sig(context)      ((context)->uc_mcontext->__ss.__cs)
 296 #define DS_sig(context)      ((context)->uc_mcontext->__ss.__ds)
 297 #define ES_sig(context)      ((context)->uc_mcontext->__ss.__es)
 298 #define FS_sig(context)      ((context)->uc_mcontext->__ss.__fs)
 299 #define GS_sig(context)      ((context)->uc_mcontext->__ss.__gs)
 300 #define SS_sig(context)      ((context)->uc_mcontext->__ss.__ss)
 301 #define EFL_sig(context)     ((context)->uc_mcontext->__ss.__eflags)
 302 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__eip))
 303 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__esp))
 304 #define TRAP_sig(context)    ((context)->uc_mcontext->__es.__trapno)
 305 #define ERROR_sig(context)   ((context)->uc_mcontext->__es.__err)
 306 #define FPU_sig(context)     NULL
 307 #define FPUX_sig(context)    ((XMM_SAVE_AREA32 *)&(context)->uc_mcontext->__fs.__fpu_fcw)
 308 #else
 309 #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
 310 #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
 311 #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
 312 #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
 313 #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
 314 #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
 315 #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
 316 #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
 317 #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
 318 #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
 319 #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
 320 #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
 321 #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
 322 #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
 323 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
 324 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
 325 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 326 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 327 #define FPU_sig(context)     NULL
 328 #define FPUX_sig(context)    ((XMM_SAVE_AREA32 *)&(context)->uc_mcontext->fs.fpu_fcw)
 329 #endif
 330
 331 #endif /* __APPLE__ */
 332
 333 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 334
 335 typedef int (*wine_signal_handler)(unsigned int sig);
 336
 337 static size_t signal_stack_mask;
 338 static size_t signal_stack_size;
 339
 340 static wine_signal_handler handlers[256];
 341
 342 static int fpux_support;  /* whether the CPU support extended fpu context */
 343
 344 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( const CONTEXT *context );
 345
 346 enum i386_trap_code
 347 {
 348     TRAP_x86_UNKNOWN    = -1,  /* Unknown fault (TRAP_sig not defined) */
 349 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 350     TRAP_x86_DIVIDE     = T_DIVIDE,     /* Division by zero exception */
 351     TRAP_x86_TRCTRAP    = T_TRCTRAP,    /* Single-step exception */
 352     TRAP_x86_NMI        = T_NMI,        /* NMI interrupt */
 353     TRAP_x86_BPTFLT     = T_BPTFLT,     /* Breakpoint exception */
 354     TRAP_x86_OFLOW      = T_OFLOW,      /* Overflow exception */
 355     TRAP_x86_BOUND      = T_BOUND,      /* Bound range exception */
 356     TRAP_x86_PRIVINFLT  = T_PRIVINFLT,  /* Invalid opcode exception */
 357     TRAP_x86_DNA        = T_DNA,        /* Device not available exception */
 358     TRAP_x86_DOUBLEFLT  = T_DOUBLEFLT,  /* Double fault exception */
 359     TRAP_x86_FPOPFLT    = T_FPOPFLT,    /* Coprocessor segment overrun */
 360     TRAP_x86_TSSFLT     = T_TSSFLT,     /* Invalid TSS exception */
 361     TRAP_x86_SEGNPFLT   = T_SEGNPFLT,   /* Segment not present exception */
 362     TRAP_x86_STKFLT     = T_STKFLT,     /* Stack fault */
 363     TRAP_x86_PROTFLT    = T_PROTFLT,    /* General protection fault */
 364     TRAP_x86_PAGEFLT    = T_PAGEFLT,    /* Page fault */
 365     TRAP_x86_ARITHTRAP  = T_ARITHTRAP,  /* Floating point exception */
 366     TRAP_x86_ALIGNFLT   = T_ALIGNFLT,   /* Alignment check exception */
 367     TRAP_x86_MCHK       = T_MCHK,       /* Machine check exception */
 368     TRAP_x86_CACHEFLT   = T_XMMFLT      /* Cache flush exception */
 369 #else
 370     TRAP_x86_DIVIDE     = 0,   /* Division by zero exception */
 371     TRAP_x86_TRCTRAP    = 1,   /* Single-step exception */
 372     TRAP_x86_NMI        = 2,   /* NMI interrupt */
 373     TRAP_x86_BPTFLT     = 3,   /* Breakpoint exception */
 374     TRAP_x86_OFLOW      = 4,   /* Overflow exception */
 375     TRAP_x86_BOUND      = 5,   /* Bound range exception */
 376     TRAP_x86_PRIVINFLT  = 6,   /* Invalid opcode exception */
 377     TRAP_x86_DNA        = 7,   /* Device not available exception */
 378     TRAP_x86_DOUBLEFLT  = 8,   /* Double fault exception */
 379     TRAP_x86_FPOPFLT    = 9,   /* Coprocessor segment overrun */
 380     TRAP_x86_TSSFLT     = 10,  /* Invalid TSS exception */
 381     TRAP_x86_SEGNPFLT   = 11,  /* Segment not present exception */
 382     TRAP_x86_STKFLT     = 12,  /* Stack fault */
 383     TRAP_x86_PROTFLT    = 13,  /* General protection fault */
 384     TRAP_x86_PAGEFLT    = 14,  /* Page fault */
 385     TRAP_x86_ARITHTRAP  = 16,  /* Floating point exception */
 386     TRAP_x86_ALIGNFLT   = 17,  /* Alignment check exception */
 387     TRAP_x86_MCHK       = 18,  /* Machine check exception */
 388     TRAP_x86_CACHEFLT   = 19   /* SIMD exception (via SIGFPE) if CPU is SSE capable
 389                                   otherwise Cache flush exception (via SIGSEV) */
 390 #endif
 391 };
 392
 393
 394 /***********************************************************************
 395  *           dispatch_signal
 396  */
 397 static inline int dispatch_signal(unsigned int sig)
 398 {
 399     if (handlers[sig] == NULL) return 0;
 400     return handlers[sig](sig);
 401 }
 402
 403
 404 /***********************************************************************
 405  *           get_trap_code
 406  *
 407  * Get the trap code for a signal.
 408  */
 409 static inline enum i386_trap_code get_trap_code( const SIGCONTEXT *sigcontext )
 410 {
 411 #ifdef TRAP_sig
 412     return TRAP_sig(sigcontext);
 413 #else
 414     return TRAP_x86_UNKNOWN;  /* unknown trap code */
 415 #endif
 416 }
 417
 418 /***********************************************************************
 419  *           get_error_code
 420  *
 421  * Get the error code for a signal.
 422  */
 423 static inline WORD get_error_code( const SIGCONTEXT *sigcontext )
 424 {
 425 #ifdef ERROR_sig
 426     return ERROR_sig(sigcontext);
 427 #else
 428     return 0;
 429 #endif
 430 }
 431
 432 /***********************************************************************
 433  *           get_signal_stack
 434  *
 435  * Get the base of the signal stack for the current thread.
 436  */
 437 static inline void *get_signal_stack(void)
 438 {
 439     return (char *)NtCurrentTeb() + 4096;
 440 }
 441
 442
 443 /***********************************************************************
 444  *           get_current_teb
 445  *
 446  * Get the current teb based on the stack pointer.
 447  */
 448 static inline TEB *get_current_teb(void)
 449 {
 450     unsigned long esp;
 451     __asm__("movl %%esp,%0" : "=g" (esp) );
 452     return (TEB *)(esp & ~signal_stack_mask);
 453 }
 454
 455
 456 #ifdef __HAVE_VM86
 457 /***********************************************************************
 458  *           save_vm86_context
 459  *
 460  * Set the register values from a vm86 structure.
 461  */
 462 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 463 {
 464     context->ContextFlags = CONTEXT_FULL;
 465     context->Eax    = vm86->regs.eax;
 466     context->Ebx    = vm86->regs.ebx;
 467     context->Ecx    = vm86->regs.ecx;
 468     context->Edx    = vm86->regs.edx;
 469     context->Esi    = vm86->regs.esi;
 470     context->Edi    = vm86->regs.edi;
 471     context->Esp    = vm86->regs.esp;
 472     context->Ebp    = vm86->regs.ebp;
 473     context->Eip    = vm86->regs.eip;
 474     context->SegCs  = vm86->regs.cs;
 475     context->SegDs  = vm86->regs.ds;
 476     context->SegEs  = vm86->regs.es;
 477     context->SegFs  = vm86->regs.fs;
 478     context->SegGs  = vm86->regs.gs;
 479     context->SegSs  = vm86->regs.ss;
 480     context->EFlags = vm86->regs.eflags;
 481 }
 482
 483
 484 /***********************************************************************
 485  *           restore_vm86_context
 486  *
 487  * Build a vm86 structure from the register values.
 488  */
 489 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 490 {
 491     vm86->regs.eax    = context->Eax;
 492     vm86->regs.ebx    = context->Ebx;
 493     vm86->regs.ecx    = context->Ecx;
 494     vm86->regs.edx    = context->Edx;
 495     vm86->regs.esi    = context->Esi;
 496     vm86->regs.edi    = context->Edi;
 497     vm86->regs.esp    = context->Esp;
 498     vm86->regs.ebp    = context->Ebp;
 499     vm86->regs.eip    = context->Eip;
 500     vm86->regs.cs     = context->SegCs;
 501     vm86->regs.ds     = context->SegDs;
 502     vm86->regs.es     = context->SegEs;
 503     vm86->regs.fs     = context->SegFs;
 504     vm86->regs.gs     = context->SegGs;
 505     vm86->regs.ss     = context->SegSs;
 506     vm86->regs.eflags = context->EFlags;
 507 }
 508
 509
 510 /**********************************************************************
 511  *              merge_vm86_pending_flags
 512  *
 513  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 514  * raises exception if there are pending events and VIF flag
 515  * has been turned on.
 516  *
 517  * Called from __wine_enter_vm86 because vm86_enter
 518  * doesn't check for pending events.
 519  *
 520  * Called from raise_vm86_sti_exception to check for
 521  * pending events in a signal safe way.
 522  */
 523 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 524 {
 525     BOOL check_pending = TRUE;
 526     struct vm86plus_struct *vm86 =
 527         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 528
 529     /*
 530      * In order to prevent a race when SIGUSR2 occurs while
 531      * we are returning from exception handler, pending events
 532      * will be rechecked after each raised exception.
 533      */
 534     while (check_pending && get_vm86_teb_info()->vm86_pending)
 535     {
 536         check_pending = FALSE;
 537         ntdll_get_thread_data()->vm86_ptr = NULL;
 538
 539         /*
 540          * If VIF is set, throw exception.
 541          * Note that SIGUSR2 may turn VIF flag off so
 542          * VIF check must occur only when TEB.vm86_ptr is NULL.
 543          */
 544         if (vm86->regs.eflags & VIF_MASK)
 545         {
 546             CONTEXT vcontext;
 547             save_vm86_context( &vcontext, vm86 );
 548
 549             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 550             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 551             rec->ExceptionRecord  = NULL;
 552             rec->NumberParameters = 0;
 553             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 554
 555             vcontext.EFlags &= ~VIP_MASK;
 556             get_vm86_teb_info()->vm86_pending = 0;
 557             __regs_RtlRaiseException( rec, &vcontext );
 558
 559             restore_vm86_context( &vcontext, vm86 );
 560             check_pending = TRUE;
 561         }
 562
 563         ntdll_get_thread_data()->vm86_ptr = vm86;
 564     }
 565
 566     /*
 567      * Merge VIP flags in a signal safe way. This requires
 568      * that the following operation compiles into atomic
 569      * instruction.
 570      */
 571     vm86->regs.eflags |= get_vm86_teb_info()->vm86_pending;
 572 }
 573 #endif /* __HAVE_VM86 */
 574
 575
 576 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 577
 578
 579 /***********************************************************************
 580  *           init_handler
 581  *
 582  * Handler initialization when the full context is not needed.
 583  */
 584 static inline void *init_handler( const SIGCONTEXT *sigcontext, WORD *fs, WORD *gs )
 585 {
 586     void *stack = (void *)(ESP_sig(sigcontext) & ~3);
 587     TEB *teb = get_current_teb();
 588     struct ntdll_thread_data *thread_data = (struct ntdll_thread_data *)teb->SystemReserved2;
 589
 590     /* get %fs and %gs at time of the fault */
 591 #ifdef FS_sig
 592     *fs = LOWORD(FS_sig(sigcontext));
 593 #else
 594     *fs = wine_get_fs();
 595 #endif
 596 #ifdef GS_sig
 597     *gs = LOWORD(GS_sig(sigcontext));
 598 #else
 599     *gs = wine_get_gs();
 600 #endif
 601
 602     wine_set_fs( thread_data->fs );
 603
 604     /* now restore a proper %gs for the fault handler */
 605     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 606         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 607     {
 608         /*
 609          * Win16 or DOS protected mode. Note that during switch
 610          * from 16-bit mode to linear mode, CS may be set to system
 611          * segment before FS is restored. Fortunately, in this case
 612          * SS is still non-system segment. This is why both CS and SS
 613          * are checked.
 614          */
 615         wine_set_gs( thread_data->gs );
 616         stack = teb->WOW32Reserved;
 617     }
 618 #ifdef __HAVE_VM86
 619     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 620     {
 621         unsigned int *int_stack = stack;
 622         /* fetch the saved %gs from the stack */
 623         wine_set_gs( int_stack[0] );
 624     }
 625 #endif
 626     else  /* 32-bit mode */
 627     {
 628 #ifdef GS_sig
 629         wine_set_gs( GS_sig(sigcontext) );
 630 #endif
 631     }
 632     return stack;
 633 }
 634
 635
 636 /***********************************************************************
 637  *           save_fpu
 638  *
 639  * Save the thread FPU context.
 640  */
 641 static inline void save_fpu( CONTEXT *context )
 642 {
 643 #ifdef __GNUC__
 644     context->ContextFlags |= CONTEXT_FLOATING_POINT;
 645     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 646 #endif
 647 }
 648
 649
 650 /***********************************************************************
 651  *           save_fpux
 652  *
 653  * Save the thread FPU extended context.
 654  */
 655 static inline void save_fpux( CONTEXT *context )
 656 {
 657 #ifdef __GNUC__
 658     /* we have to enforce alignment by hand */
 659     char buffer[sizeof(XMM_SAVE_AREA32) + 16];
 660     XMM_SAVE_AREA32 *state = (XMM_SAVE_AREA32 *)(((ULONG_PTR)buffer + 15) & ~15);
 661
 662     __asm__ __volatile__( "fxsave %0" : "=m" (*state) );
 663     context->ContextFlags |= CONTEXT_EXTENDED_REGISTERS;
 664     memcpy( context->ExtendedRegisters, state, sizeof(*state) );
 665 #endif
 666 }
 667
 668
 669 /***********************************************************************
 670  *           restore_fpu
 671  *
 672  * Restore the FPU context to a sigcontext.
 673  */
 674 static inline void restore_fpu( const CONTEXT *context )
 675 {
 676     FLOATING_SAVE_AREA float_status = context->FloatSave;
 677     /* reset the current interrupt status */
 678     float_status.StatusWord &= float_status.ControlWord | 0xffffff80;
 679 #ifdef __GNUC__
 680     __asm__ __volatile__( "frstor %0; fwait" : : "m" (float_status) );
 681 #endif  /* __GNUC__ */
 682 }
 683
 684
 685 /***********************************************************************
 686  *           restore_fpux
 687  *
 688  * Restore the FPU extended context to a sigcontext.
 689  */
 690 static inline void restore_fpux( const CONTEXT *context )
 691 {
 692 #ifdef __GNUC__
 693     /* we have to enforce alignment by hand */
 694     char buffer[sizeof(XMM_SAVE_AREA32) + 16];
 695     XMM_SAVE_AREA32 *state = (XMM_SAVE_AREA32 *)(((ULONG_PTR)buffer + 15) & ~15);
 696
 697     memcpy( state, context->ExtendedRegisters, sizeof(*state) );
 698     /* reset the current interrupt status */
 699     state->StatusWord &= state->ControlWord | 0xff80;
 700     __asm__ __volatile__( "fxrstor %0" : : "m" (*state) );
 701 #endif
 702 }
 703
 704
 705 /***********************************************************************
 706  *           fpux_to_fpu
 707  *
 708  * Build a standard FPU context from an extended one.
 709  */
 710 static void fpux_to_fpu( FLOATING_SAVE_AREA *fpu, const XMM_SAVE_AREA32 *fpux )
 711 {
 712     unsigned int i, tag, stack_top;
 713
 714     fpu->ControlWord   = fpux->ControlWord | 0xffff0000;
 715     fpu->StatusWord    = fpux->StatusWord | 0xffff0000;
 716     fpu->ErrorOffset   = fpux->ErrorOffset;
 717     fpu->ErrorSelector = fpux->ErrorSelector | (fpux->ErrorOpcode << 16);
 718     fpu->DataOffset    = fpux->DataOffset;
 719     fpu->DataSelector  = fpux->DataSelector;
 720     fpu->Cr0NpxState   = fpux->StatusWord | 0xffff0000;
 721
 722     stack_top = (fpux->StatusWord >> 11) & 7;
 723     fpu->TagWord = 0xffff0000;
 724     for (i = 0; i < 8; i++)
 725     {
 726         memcpy( &fpu->RegisterArea[10 * i], &fpux->FloatRegisters[i], 10 );
 727         if (!(fpux->TagWord & (1 << i))) tag = 3;  /* empty */
 728         else
 729         {
 730             const M128A *reg = &fpux->FloatRegisters[(i - stack_top) & 7];
 731             if ((reg->High & 0x7fff) == 0x7fff)  /* exponent all ones */
 732             {
 733                 tag = 2;  /* special */
 734             }
 735             else if (!(reg->High & 0x7fff))  /* exponent all zeroes */
 736             {
 737                 if (reg->Low) tag = 2;  /* special */
 738                 else tag = 1;  /* zero */
 739             }
 740             else
 741             {
 742                 if (reg->Low >> 63) tag = 0;  /* valid */
 743                 else tag = 2;  /* special */
 744             }
 745         }
 746         fpu->TagWord |= tag << (2 * i);
 747     }
 748 }
 749
 750
 751 /***********************************************************************
 752  *           save_context
 753  *
 754  * Build a context structure from the signal info.
 755  */
 756 static inline void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext, WORD fs, WORD gs )
 757 {
 758     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 759     FLOATING_SAVE_AREA *fpu = FPU_sig(sigcontext);
 760     XMM_SAVE_AREA32 *fpux = FPUX_sig(sigcontext);
 761
 762     memset(context, 0, sizeof(*context));
 763     context->ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
 764     context->Eax          = EAX_sig(sigcontext);
 765     context->Ebx          = EBX_sig(sigcontext);
 766     context->Ecx          = ECX_sig(sigcontext);
 767     context->Edx          = EDX_sig(sigcontext);
 768     context->Esi          = ESI_sig(sigcontext);
 769     context->Edi          = EDI_sig(sigcontext);
 770     context->Ebp          = EBP_sig(sigcontext);
 771     context->EFlags       = EFL_sig(sigcontext);
 772     context->Eip          = EIP_sig(sigcontext);
 773     context->Esp          = ESP_sig(sigcontext);
 774     context->SegCs        = LOWORD(CS_sig(sigcontext));
 775     context->SegDs        = LOWORD(DS_sig(sigcontext));
 776     context->SegEs        = LOWORD(ES_sig(sigcontext));
 777     context->SegFs        = fs;
 778     context->SegGs        = gs;
 779     context->SegSs        = LOWORD(SS_sig(sigcontext));
 780     context->Dr0          = regs->dr0;
 781     context->Dr1          = regs->dr1;
 782     context->Dr2          = regs->dr2;
 783     context->Dr3          = regs->dr3;
 784     context->Dr6          = regs->dr6;
 785     context->Dr7          = regs->dr7;
 786
 787     if (fpu)
 788     {
 789         context->ContextFlags |= CONTEXT_FLOATING_POINT;
 790         context->FloatSave = *fpu;
 791     }
 792     if (fpux)
 793     {
 794         context->ContextFlags |= CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS;
 795         memcpy( context->ExtendedRegisters, fpux, sizeof(*fpux) );
 796         fpux_support = 1;
 797         if (!fpu) fpux_to_fpu( &context->FloatSave, fpux );
 798     }
 799     if (!fpu && !fpux) save_fpu( context );
 800 }
 801
 802
 803 /***********************************************************************
 804  *           restore_context
 805  *
 806  * Restore the signal info from the context.
 807  */
 808 static inline void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 809 {
 810     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 811     FLOATING_SAVE_AREA *fpu = FPU_sig(sigcontext);
 812     XMM_SAVE_AREA32 *fpux = FPUX_sig(sigcontext);
 813
 814     regs->dr0 = context->Dr0;
 815     regs->dr1 = context->Dr1;
 816     regs->dr2 = context->Dr2;
 817     regs->dr3 = context->Dr3;
 818     regs->dr6 = context->Dr6;
 819     regs->dr7 = context->Dr7;
 820     EAX_sig(sigcontext) = context->Eax;
 821     EBX_sig(sigcontext) = context->Ebx;
 822     ECX_sig(sigcontext) = context->Ecx;
 823     EDX_sig(sigcontext) = context->Edx;
 824     ESI_sig(sigcontext) = context->Esi;
 825     EDI_sig(sigcontext) = context->Edi;
 826     EBP_sig(sigcontext) = context->Ebp;
 827     EFL_sig(sigcontext) = context->EFlags;
 828     EIP_sig(sigcontext) = context->Eip;
 829     ESP_sig(sigcontext) = context->Esp;
 830     CS_sig(sigcontext)  = context->SegCs;
 831     DS_sig(sigcontext)  = context->SegDs;
 832     ES_sig(sigcontext)  = context->SegEs;
 833     SS_sig(sigcontext)  = context->SegSs;
 834 #ifdef GS_sig
 835     GS_sig(sigcontext)  = context->SegGs;
 836 #else
 837     wine_set_gs( context->SegGs );
 838 #endif
 839 #ifdef FS_sig
 840     FS_sig(sigcontext)  = context->SegFs;
 841 #else
 842     wine_set_fs( context->SegFs );
 843 #endif
 844
 845     if (fpu) *fpu = context->FloatSave;
 846     if (fpux) memcpy( fpux, context->ExtendedRegisters, sizeof(*fpux) );
 847     if (!fpu && !fpux) restore_fpu( context );
 848 }
 849
 850
 851 /***********************************************************************
 852  *              get_cpu_context
 853  *
 854  * Register function to get the context of the current thread.
 855  */
 856 void WINAPI __regs_get_cpu_context( CONTEXT *context, CONTEXT *regs )
 857 {
 858     *context = *regs;
 859     if (fpux_support) save_fpux( context );
 860     else save_fpu( context );
 861 }
 862 DEFINE_REGS_ENTRYPOINT( get_cpu_context, 4, 4 )
 863
 864
 865 /***********************************************************************
 866  *           set_cpu_context
 867  *
 868  * Set the new CPU context. Used by NtSetContextThread.
 869  */
 870 void set_cpu_context( const CONTEXT *context )
 871 {
 872     DWORD flags = context->ContextFlags & ~CONTEXT_i386;
 873
 874     if ((flags & CONTEXT_EXTENDED_REGISTERS) && fpux_support) restore_fpux( context );
 875     else if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
 876
 877     if (flags & CONTEXT_DEBUG_REGISTERS)
 878     {
 879         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 880         regs->dr0 = context->Dr0;
 881         regs->dr1 = context->Dr1;
 882         regs->dr2 = context->Dr2;
 883         regs->dr3 = context->Dr3;
 884         regs->dr6 = context->Dr6;
 885         regs->dr7 = context->Dr7;
 886     }
 887     if (flags & CONTEXT_FULL)
 888     {
 889         if (!(flags & CONTEXT_CONTROL))
 890             FIXME( "setting partial context (%x) not supported\n", flags );
 891         else if (flags & CONTEXT_SEGMENTS)
 892             __wine_call_from_32_restore_regs( context );
 893         else
 894         {
 895             CONTEXT newcontext = *context;
 896             newcontext.SegDs = wine_get_ds();
 897             newcontext.SegEs = wine_get_es();
 898             newcontext.SegFs = wine_get_fs();
 899             newcontext.SegGs = wine_get_gs();
 900             __wine_call_from_32_restore_regs( &newcontext );
 901         }
 902     }
 903 }
 904
 905
 906 /***********************************************************************
 907  *           is_privileged_instr
 908  *
 909  * Check if the fault location is a privileged instruction.
 910  * Based on the instruction emulation code in dlls/kernel/instr.c.
 911  */
 912 static inline DWORD is_privileged_instr( CONTEXT86 *context )
 913 {
 914     const BYTE *instr;
 915     unsigned int prefix_count = 0;
 916
 917     if (!wine_ldt_is_system( context->SegCs )) return 0;
 918     instr = (BYTE *)context->Eip;
 919
 920     for (;;) switch(*instr)
 921     {
 922     /* instruction prefixes */
 923     case 0x2e:  /* %cs: */
 924     case 0x36:  /* %ss: */
 925     case 0x3e:  /* %ds: */
 926     case 0x26:  /* %es: */
 927     case 0x64:  /* %fs: */
 928     case 0x65:  /* %gs: */
 929     case 0x66:  /* opcode size */
 930     case 0x67:  /* addr size */
 931     case 0xf0:  /* lock */
 932     case 0xf2:  /* repne */
 933     case 0xf3:  /* repe */
 934         if (++prefix_count >= 15) return EXCEPTION_ILLEGAL_INSTRUCTION;
 935         instr++;
 936         continue;
 937
 938     case 0x0f: /* extended instruction */
 939         switch(instr[1])
 940         {
 941         case 0x20: /* mov crX, reg */
 942         case 0x21: /* mov drX, reg */
 943         case 0x22: /* mov reg, crX */
 944         case 0x23: /* mov reg drX */
 945             return EXCEPTION_PRIV_INSTRUCTION;
 946         }
 947         return 0;
 948     case 0x6c: /* insb (%dx) */
 949     case 0x6d: /* insl (%dx) */
 950     case 0x6e: /* outsb (%dx) */
 951     case 0x6f: /* outsl (%dx) */
 952     case 0xcd: /* int $xx */
 953     case 0xe4: /* inb al,XX */
 954     case 0xe5: /* in (e)ax,XX */
 955     case 0xe6: /* outb XX,al */
 956     case 0xe7: /* out XX,(e)ax */
 957     case 0xec: /* inb (%dx),%al */
 958     case 0xed: /* inl (%dx),%eax */
 959     case 0xee: /* outb %al,(%dx) */
 960     case 0xef: /* outl %eax,(%dx) */
 961     case 0xf4: /* hlt */
 962     case 0xfa: /* cli */
 963     case 0xfb: /* sti */
 964         return EXCEPTION_PRIV_INSTRUCTION;
 965     default:
 966         return 0;
 967     }
 968 }
 969
 970
 971 #include "pshpack1.h"
 972 struct atl_thunk
 973 {
 974     DWORD movl;  /* movl this,4(%esp) */
 975     DWORD this;
 976     BYTE  jmp;   /* jmp func */
 977     int   func;
 978 };
 979 #include "poppack.h"
 980
 981 /**********************************************************************
 982  *              check_atl_thunk
 983  *
 984  * Check if code destination is an ATL thunk, and emulate it if so.
 985  */
 986 static BOOL check_atl_thunk( EXCEPTION_RECORD *rec, CONTEXT *context )
 987 {
 988     const struct atl_thunk *thunk = (const struct atl_thunk *)rec->ExceptionInformation[1];
 989     BOOL ret = FALSE;
 990
 991     __TRY
 992     {
 993         if (thunk->movl == 0x042444c7 && thunk->jmp == 0xe9)
 994         {
 995             *((DWORD *)context->Esp + 1) = thunk->this;
 996             context->Eip = (DWORD_PTR)(&thunk->func + 1) + thunk->func;
 997             TRACE( "emulating ATL thunk at %p, func=%08x arg=%08x\n",
 998                    thunk, context->Eip, *((DWORD *)context->Esp + 1) );
 999             ret = TRUE;
1000         }
1001     }
1002     __EXCEPT_PAGE_FAULT
1003     {
1004         return FALSE;
1005     }
1006     __ENDTRY
1007     return ret;
1008 }
1009
1010
1011 /***********************************************************************
1012  *           setup_exception
1013  *
1014  * Setup a proper stack frame for the raise function, and modify the
1015  * sigcontext so that the return from the signal handler will call
1016  * the raise function.
1017  */
1018 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
1019 {
1020     struct stack_layout
1021     {
1022         void             *ret_addr;      /* return address from raise_func */
1023         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
1024         CONTEXT          *context_ptr;   /* second arg for raise_func */
1025         CONTEXT           context;
1026         EXCEPTION_RECORD  rec;
1027         DWORD             ebp;
1028         DWORD             eip;
1029     } *stack;
1030
1031     WORD fs, gs;
1032
1033     stack = init_handler( sigcontext, &fs, &gs );
1034
1035     /* stack sanity checks */
1036
1037     if ((char *)stack >= (char *)get_signal_stack() &&
1038         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
1039     {
1040         WINE_ERR( "nested exception on signal stack in thread %04x eip %08x esp %08x stack %p-%p\n",
1041                   GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
1042                   (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
1043                   NtCurrentTeb()->Tib.StackBase );
1044         server_abort_thread(1);
1045     }
1046
1047     if (stack - 1 > stack || /* check for overflow in subtraction */
1048         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
1049         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
1050     {
1051         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
1052         if (diff < 4096)
1053         {
1054             WINE_ERR( "stack overflow %u bytes in thread %04x eip %08x esp %08x stack %p-%p\n",
1055                       diff, GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
1056                       (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
1057                       NtCurrentTeb()->Tib.StackBase );
1058             server_abort_thread(1);
1059         }
1060         else WARN( "exception outside of stack limits in thread %04x eip %08x esp %08x stack %p-%p\n",
1061                    GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
1062                    (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
1063                    NtCurrentTeb()->Tib.StackBase );
1064     }
1065
1066     stack--;  /* push the stack_layout structure */
1067 #if defined(VALGRIND_MAKE_MEM_UNDEFINED)
1068     VALGRIND_MAKE_MEM_UNDEFINED(stack, sizeof(*stack));
1069 #elif defined(VALGRIND_MAKE_WRITABLE)
1070     VALGRIND_MAKE_WRITABLE(stack, sizeof(*stack));
1071 #endif
1072     stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
1073     stack->rec_ptr      = &stack->rec;
1074     stack->context_ptr  = &stack->context;
1075
1076     stack->rec.ExceptionRecord  = NULL;
1077     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1078     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
1079     stack->rec.NumberParameters = 0;
1080
1081     save_context( &stack->context, sigcontext, fs, gs );
1082
1083     /* now modify the sigcontext to return to the raise function */
1084     ESP_sig(sigcontext) = (DWORD)stack;
1085     EIP_sig(sigcontext) = (DWORD)func;
1086     /* clear single-step and align check flag */
1087     EFL_sig(sigcontext) &= ~(0x100|0x40000);
1088     CS_sig(sigcontext)  = wine_get_cs();
1089     DS_sig(sigcontext)  = wine_get_ds();
1090     ES_sig(sigcontext)  = wine_get_es();
1091     FS_sig(sigcontext)  = wine_get_fs();
1092     GS_sig(sigcontext)  = wine_get_gs();
1093     SS_sig(sigcontext)  = wine_get_ss();
1094
1095     return stack->rec_ptr;
1096 }
1097
1098
1099 /***********************************************************************
1100  *           get_exception_context
1101  *
1102  * Get a pointer to the context built by setup_exception.
1103  */
1104 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
1105 {
1106     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
1107 }
1108
1109
1110 /**********************************************************************
1111  *              get_fpu_code
1112  *
1113  * Get the FPU exception code from the FPU status.
1114  */
1115 static inline DWORD get_fpu_code( const CONTEXT *context )
1116 {
1117     DWORD status = context->FloatSave.StatusWord;
1118
1119     if (status & 0x01)  /* IE */
1120     {
1121         if (status & 0x40)  /* SF */
1122             return EXCEPTION_FLT_STACK_CHECK;
1123         else
1124             return EXCEPTION_FLT_INVALID_OPERATION;
1125     }
1126     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
1127     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
1128     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
1129     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
1130     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
1131     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
1132 }
1133
1134
1135 /**********************************************************************
1136  *              raise_segv_exception
1137  */
1138 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1139 {
1140     switch(rec->ExceptionCode)
1141     {
1142     case EXCEPTION_ACCESS_VIOLATION:
1143         if (rec->NumberParameters == 2)
1144         {
1145             if (rec->ExceptionInformation[0] == EXCEPTION_EXECUTE_FAULT && check_atl_thunk( rec, context ))
1146                 goto done;
1147             rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] );
1148         }
1149         break;
1150     case EXCEPTION_DATATYPE_MISALIGNMENT:
1151         /* FIXME: pass through exception handler first? */
1152         if (context->EFlags & 0x00040000)
1153         {
1154             /* Disable AC flag, return */
1155             context->EFlags &= ~0x00040000;
1156             goto done;
1157         }
1158         break;
1159     }
1160     __regs_RtlRaiseException( rec, context );
1161 done:
1162     NtSetContextThread( GetCurrentThread(), context );
1163 }
1164
1165
1166 /**********************************************************************
1167  *              raise_trap_exception
1168  */
1169 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1170 {
1171     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1172     {
1173         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
1174
1175         /* when single stepping can't tell whether this is a hw bp or a
1176          * single step interrupt. try to avoid as much overhead as possible
1177          * and only do a server call if there is any hw bp enabled. */
1178
1179         if( !(context->EFlags & 0x100) || (regs->dr7 & 0xff) )
1180         {
1181             /* (possible) hardware breakpoint, fetch the debug registers */
1182             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1183             NtGetContextThread(GetCurrentThread(), context);
1184             context->ContextFlags |= CONTEXT_FULL;  /* restore flags */
1185         }
1186
1187         context->EFlags &= ~0x100;  /* clear single-step flag */
1188     }
1189
1190     __regs_RtlRaiseException( rec, context );
1191     NtSetContextThread( GetCurrentThread(), context );
1192 }
1193
1194
1195 /**********************************************************************
1196  *              raise_exception
1197  *
1198  * Generic raise function for exceptions that don't need special treatment.
1199  */
1200 static void WINAPI raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1201 {
1202     __regs_RtlRaiseException( rec, context );
1203     NtSetContextThread( GetCurrentThread(), context );
1204 }
1205
1206
1207 #ifdef __HAVE_VM86
1208 /**********************************************************************
1209  *              raise_vm86_sti_exception
1210  */
1211 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1212 {
1213     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1214     get_vm86_teb_info()->vm86_pending |= VIP_MASK;
1215
1216     if (ntdll_get_thread_data()->vm86_ptr)
1217     {
1218         if (((char*)context->Eip >= (char*)vm86_return) &&
1219             ((char*)context->Eip <= (char*)vm86_return_end) &&
1220             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1221             /* exiting from VM86, can't throw */
1222             goto done;
1223         }
1224         merge_vm86_pending_flags( rec );
1225     }
1226     else if (get_vm86_teb_info()->dpmi_vif &&
1227              !wine_ldt_is_system(context->SegCs) &&
1228              !wine_ldt_is_system(context->SegSs))
1229     {
1230         /* Executing DPMI code and virtual interrupts are enabled. */
1231         get_vm86_teb_info()->vm86_pending = 0;
1232         __regs_RtlRaiseException( rec, context );
1233     }
1234 done:
1235     NtSetContextThread( GetCurrentThread(), context );
1236 }
1237
1238
1239 /**********************************************************************
1240  *              usr2_handler
1241  *
1242  * Handler for SIGUSR2.
1243  * We use it to signal that the running __wine_enter_vm86() should
1244  * immediately set VIP_MASK, causing pending events to be handled
1245  * as early as possible.
1246  */
1247 static void usr2_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1248 {
1249     EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_vm86_sti_exception );
1250     rec->ExceptionCode = EXCEPTION_VM86_STI;
1251 }
1252 #endif /* __HAVE_VM86 */
1253
1254
1255 /**********************************************************************
1256  *              segv_handler
1257  *
1258  * Handler for SIGSEGV and related errors.
1259  */
1260 static void segv_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1261 {
1262     SIGCONTEXT *context = sigcontext;
1263     EXCEPTION_RECORD *rec = setup_exception( context, raise_segv_exception );
1264
1265     switch(get_trap_code(context))
1266     {
1267     case TRAP_x86_OFLOW:   /* Overflow exception */
1268         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1269         break;
1270     case TRAP_x86_BOUND:   /* Bound range exception */
1271         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1272         break;
1273     case TRAP_x86_PRIVINFLT:   /* Invalid opcode exception */
1274         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1275         break;
1276     case TRAP_x86_STKFLT:  /* Stack fault */
1277         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1278         break;
1279     case TRAP_x86_SEGNPFLT:  /* Segment not present exception */
1280     case TRAP_x86_PROTFLT:   /* General protection fault */
1281     case TRAP_x86_UNKNOWN:   /* Unknown fault code */
1282         {
1283             WORD err = get_error_code(context);
1284             if (!err && (rec->ExceptionCode = is_privileged_instr( get_exception_context(rec) ))) break;
1285             rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1286             rec->NumberParameters = 2;
1287             rec->ExceptionInformation[0] = 0;
1288             /* if error contains a LDT selector, use that as fault address */
1289             if ((err & 7) == 4 && !wine_ldt_is_system( err | 7 ))
1290                 rec->ExceptionInformation[1] = err & ~7;
1291             else
1292                 rec->ExceptionInformation[1] = 0xffffffff;
1293         }
1294         break;
1295     case TRAP_x86_PAGEFLT:  /* Page fault */
1296         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1297         rec->NumberParameters = 2;
1298         rec->ExceptionInformation[0] = (get_error_code(context) >> 1) & 0x09;
1299         rec->ExceptionInformation[1] = (ULONG_PTR)siginfo->si_addr;
1300         break;
1301     case TRAP_x86_ALIGNFLT:  /* Alignment check exception */
1302         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1303         break;
1304     default:
1305         WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
1306         /* fall through */
1307     case TRAP_x86_NMI:       /* NMI interrupt */
1308     case TRAP_x86_DNA:       /* Device not available exception */
1309     case TRAP_x86_DOUBLEFLT: /* Double fault exception */
1310     case TRAP_x86_TSSFLT:    /* Invalid TSS exception */
1311     case TRAP_x86_MCHK:      /* Machine check exception */
1312     case TRAP_x86_CACHEFLT:  /* Cache flush exception */
1313         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1314         break;
1315     }
1316 }
1317
1318
1319 /**********************************************************************
1320  *              trap_handler
1321  *
1322  * Handler for SIGTRAP.
1323  */
1324 static void trap_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1325 {
1326     SIGCONTEXT *context = sigcontext;
1327     EXCEPTION_RECORD *rec = setup_exception( context, raise_trap_exception );
1328
1329     switch(get_trap_code(context))
1330     {
1331     case TRAP_x86_TRCTRAP:  /* Single-step exception */
1332         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1333         break;
1334     case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1335         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1336         /* fall through */
1337     default:
1338         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1339         break;
1340     }
1341 }
1342
1343
1344 /**********************************************************************
1345  *              fpe_handler
1346  *
1347  * Handler for SIGFPE.
1348  */
1349 static void fpe_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1350 {
1351     CONTEXT *win_context;
1352     SIGCONTEXT *context = sigcontext;
1353     EXCEPTION_RECORD *rec = setup_exception( context, raise_exception );
1354
1355     win_context = get_exception_context( rec );
1356
1357     switch(get_trap_code(context))
1358     {
1359     case TRAP_x86_DIVIDE:   /* Division by zero exception */
1360         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1361         break;
1362     case TRAP_x86_FPOPFLT:   /* Coprocessor segment overrun */
1363         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1364         break;
1365     case TRAP_x86_ARITHTRAP:  /* Floating point exception */
1366     case TRAP_x86_UNKNOWN:    /* Unknown fault code */
1367         rec->ExceptionCode = get_fpu_code( win_context );
1368         break;
1369     case TRAP_x86_CACHEFLT:  /* SIMD exception */
1370         /* TODO:
1371          * Behaviour only tested for divide-by-zero exceptions
1372          * Check for other SIMD exceptions as well */
1373         if(siginfo->si_code != FPE_FLTDIV)
1374             FIXME("untested SIMD exception: %#x. Might not work correctly\n",
1375                   siginfo->si_code);
1376
1377         rec->ExceptionCode = STATUS_FLOAT_MULTIPLE_TRAPS;
1378         rec->NumberParameters = 1;
1379         /* no idea what meaning is actually behind this but that's what native does */
1380         rec->ExceptionInformation[0] = 0;
1381         break;
1382     default:
1383         WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
1384         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1385         break;
1386     }
1387 }
1388
1389
1390 /**********************************************************************
1391  *              int_handler
1392  *
1393  * Handler for SIGINT.
1394  *
1395  * FIXME: should not be calling external functions on the signal stack.
1396  */
1397 static void int_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1398 {
1399     WORD fs, gs;
1400     init_handler( sigcontext, &fs, &gs );
1401     if (!dispatch_signal(SIGINT))
1402     {
1403         EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_exception );
1404         rec->ExceptionCode = CONTROL_C_EXIT;
1405     }
1406 }
1407
1408 /**********************************************************************
1409  *              abrt_handler
1410  *
1411  * Handler for SIGABRT.
1412  */
1413 static void abrt_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1414 {
1415     EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_exception );
1416     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1417     rec->ExceptionFlags = EH_NONCONTINUABLE;
1418 }
1419
1420
1421 /**********************************************************************
1422  *              quit_handler
1423  *
1424  * Handler for SIGQUIT.
1425  */
1426 static void quit_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1427 {
1428     WORD fs, gs;
1429     init_handler( sigcontext, &fs, &gs );
1430     server_abort_thread(0);
1431 }
1432
1433
1434 /**********************************************************************
1435  *              usr1_handler
1436  *
1437  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1438  */
1439 static void usr1_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1440 {
1441     CONTEXT context;
1442     WORD fs, gs;
1443
1444     init_handler( sigcontext, &fs, &gs );
1445     save_context( &context, sigcontext, fs, gs );
1446     wait_suspend( &context );
1447     restore_context( &context, sigcontext );
1448 }
1449
1450
1451 /**********************************************************************
1452  *              get_signal_stack_total_size
1453  *
1454  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1455  * Must be a power of two.
1456  */
1457 size_t get_signal_stack_total_size(void)
1458 {
1459     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1460
1461     if (!signal_stack_size)
1462     {
1463         size_t size = 8192, min_size = teb_size + max( MINSIGSTKSZ, 8192 );
1464         /* find the first power of two not smaller than min_size */
1465         while (size < min_size) size *= 2;
1466         signal_stack_mask = size - 1;
1467         signal_stack_size = size - teb_size;
1468     }
1469     return signal_stack_size + teb_size;
1470 }
1471
1472
1473 /***********************************************************************
1474  *           __wine_set_signal_handler   (NTDLL.@)
1475  */
1476 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1477 {
1478     if (sig >= sizeof(handlers) / sizeof(handlers[0])) return -1;
1479     if (handlers[sig] != NULL) return -2;
1480     handlers[sig] = wsh;
1481     return 0;
1482 }
1483
1484
1485 /**********************************************************************
1486  *              SIGNAL_Init
1487  */
1488 BOOL SIGNAL_Init(void)
1489 {
1490     struct sigaction sig_act;
1491
1492 #ifdef HAVE_SIGALTSTACK
1493     stack_t ss;
1494
1495 #ifdef __APPLE__
1496     int mib[2], val = 1;
1497
1498     mib[0] = CTL_KERN;
1499     mib[1] = KERN_THALTSTACK;
1500     sysctl( mib, 2, NULL, NULL, &val, sizeof(val) );
1501 #endif
1502
1503     ss.ss_sp    = get_signal_stack();
1504     ss.ss_size  = signal_stack_size;
1505     ss.ss_flags = 0;
1506     if (sigaltstack(&ss, NULL) == -1)
1507     {
1508         perror( "sigaltstack" );
1509         return FALSE;
1510     }
1511 #endif  /* HAVE_SIGALTSTACK */
1512
1513     sig_act.sa_mask = server_block_set;
1514     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1515 #ifdef SA_ONSTACK
1516     sig_act.sa_flags |= SA_ONSTACK;
1517 #endif
1518
1519     sig_act.sa_sigaction = int_handler;
1520     if (sigaction( SIGINT, &sig_act, NULL ) == -1) goto error;
1521     sig_act.sa_sigaction = fpe_handler;
1522     if (sigaction( SIGFPE, &sig_act, NULL ) == -1) goto error;
1523     sig_act.sa_sigaction = abrt_handler;
1524     if (sigaction( SIGABRT, &sig_act, NULL ) == -1) goto error;
1525     sig_act.sa_sigaction = quit_handler;
1526     if (sigaction( SIGQUIT, &sig_act, NULL ) == -1) goto error;
1527     sig_act.sa_sigaction = usr1_handler;
1528     if (sigaction( SIGUSR1, &sig_act, NULL ) == -1) goto error;
1529
1530     sig_act.sa_sigaction = segv_handler;
1531     if (sigaction( SIGSEGV, &sig_act, NULL ) == -1) goto error;
1532     if (sigaction( SIGILL, &sig_act, NULL ) == -1) goto error;
1533 #ifdef SIGBUS
1534     if (sigaction( SIGBUS, &sig_act, NULL ) == -1) goto error;
1535 #endif
1536
1537 #ifdef SIGTRAP
1538     sig_act.sa_sigaction = trap_handler;
1539     if (sigaction( SIGTRAP, &sig_act, NULL ) == -1) goto error;
1540 #endif
1541
1542 #ifdef __HAVE_VM86
1543     sig_act.sa_sigaction = usr2_handler;
1544     if (sigaction( SIGUSR2, &sig_act, NULL ) == -1) goto error;
1545 #endif
1546
1547     return TRUE;
1548
1549  error:
1550     perror("sigaction");
1551     return FALSE;
1552 }
1553
1554
1555 #ifdef __HAVE_VM86
1556 /**********************************************************************
1557  *              __wine_enter_vm86   (NTDLL.@)
1558  *
1559  * Enter vm86 mode with the specified register context.
1560  */
1561 void __wine_enter_vm86( CONTEXT *context )
1562 {
1563     EXCEPTION_RECORD rec;
1564     int res;
1565     struct vm86plus_struct vm86;
1566
1567     memset( &vm86, 0, sizeof(vm86) );
1568     for (;;)
1569     {
1570         restore_vm86_context( context, &vm86 );
1571
1572         ntdll_get_thread_data()->vm86_ptr = &vm86;
1573         merge_vm86_pending_flags( &rec );
1574
1575         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1576         if (res < 0)
1577         {
1578             errno = -res;
1579             return;
1580         }
1581
1582         save_vm86_context( context, &vm86 );
1583
1584         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1585         rec.ExceptionRecord  = NULL;
1586         rec.ExceptionAddress = (LPVOID)context->Eip;
1587         rec.NumberParameters = 0;
1588
1589         switch(VM86_TYPE(res))
1590         {
1591         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1592             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1593             break;
1594         case VM86_TRAP: /* return due to DOS-debugger request */
1595             switch(VM86_ARG(res))
1596             {
1597             case TRAP_x86_TRCTRAP:  /* Single-step exception */
1598                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1599                 break;
1600             case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1601                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1602                 /* fall through */
1603             default:
1604                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1605                 break;
1606             }
1607             break;
1608         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1609             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1610             rec.NumberParameters = 1;
1611             rec.ExceptionInformation[0] = VM86_ARG(res);
1612             break;
1613         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1614             context->EFlags |= VIF_MASK;
1615             context->EFlags &= ~VIP_MASK;
1616             get_vm86_teb_info()->vm86_pending = 0;
1617             rec.ExceptionCode = EXCEPTION_VM86_STI;
1618             break;
1619         case VM86_PICRETURN: /* return due to pending PIC request */
1620             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1621             break;
1622         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1623         default:
1624             WINE_ERR( "unhandled result from vm86 mode %x\n", res );
1625             continue;
1626         }
1627         __regs_RtlRaiseException( &rec, context );
1628     }
1629 }
1630
1631 #else /* __HAVE_VM86 */
1632 /**********************************************************************
1633  *              __wine_enter_vm86   (NTDLL.@)
1634  */
1635 void __wine_enter_vm86( CONTEXT *context )
1636 {
1637     MESSAGE("vm86 mode not supported on this platform\n");
1638 }
1639 #endif /* __HAVE_VM86 */
1640
1641 /**********************************************************************
1642  *              DbgBreakPoint   (NTDLL.@)
1643  */
1644 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret")
1645
1646 /**********************************************************************
1647  *              DbgUserBreakPoint   (NTDLL.@)
1648  */
1649 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret")
1650
1651
1652 /**********************************************************************
1653  *              EXC_CallHandler   (internal)
1654  *
1655  * Some exception handlers depend on EBP to have a fixed position relative to
1656  * the exception frame.
1657  * Shrinker depends on (*1) doing what it does,
1658  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1659  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1660  * function calling the handler having only 5 parameters (*4).
1661  */
1662 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1663 "       pushl   %ebp\n"
1664 "       movl    %esp, %ebp\n"
1665 "       pushl   %ebx\n"
1666 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1667 "       pushl   24(%ebp)\n"
1668 "       pushl   20(%ebp)\n"
1669 "       pushl   16(%ebp)\n"
1670 "       pushl   12(%ebp)\n"
1671 "       pushl   8(%ebp)\n"
1672 "       call    " __ASM_NAME("call_exception_handler") "\n"
1673 "       popl    %ebx\n"
1674 "       leave\n"
1675 "       ret\n"
1676 )
1677 __ASM_GLOBAL_FUNC(call_exception_handler,
1678 "       pushl   %ebp\n"
1679 "       movl    %esp, %ebp\n"
1680 "       subl    $12,%esp\n"
1681 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1682 "       pushl   %edx\n"           /* handler be handled by... */
1683 "       .byte   0x64\n"
1684 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1685 "       .byte   0x64\n"
1686 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1687 "       pushl   20(%ebp)\n"
1688 "       pushl   16(%ebp)\n"
1689 "       pushl   12(%ebp)\n"
1690 "       pushl   8(%ebp)\n"
1691 "       movl    24(%ebp), %ecx\n" /* (*1) */
1692 "       call    *%ecx\n"          /* call handler. (*2) */
1693 "       .byte   0x64\n"
1694 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1695 "       .byte   0x64\n"
1696 "       popl    (0)\n"            /* exception frame. */
1697 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1698 "       popl    %ebp\n"
1699 "       ret     $20\n"            /* (*4) */
1700 )
1701 #endif  /* __i386__ */