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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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 #ifdef HAVE_UNISTD_H
  32 # include <unistd.h>
  33 #endif
  34
  35 #ifdef HAVE_SYS_PARAM_H
  36 # include <sys/param.h>
  37 #endif
  38 #ifdef HAVE_SYSCALL_H
  39 # include <syscall.h>
  40 #else
  41 # ifdef HAVE_SYS_SYSCALL_H
  42 #  include <sys/syscall.h>
  43 # endif
  44 #endif
  45
  46 #ifdef HAVE_SYS_VM86_H
  47 # include <sys/vm86.h>
  48 #endif
  49
  50 #ifdef HAVE_SYS_SIGNAL_H
  51 # include <sys/signal.h>
  52 #endif
  53
  54 #include "windef.h"
  55 #include "thread.h"
  56 #include "wine/library.h"
  57 #include "ntdll_misc.h"
  58
  59 /***********************************************************************
  60  * signal context platform-specific definitions
  61  */
  62
  63 #ifdef linux
  64 typedef struct
  65 {
  66     unsigned short sc_gs, __gsh;
  67     unsigned short sc_fs, __fsh;
  68     unsigned short sc_es, __esh;
  69     unsigned short sc_ds, __dsh;
  70     unsigned long sc_edi;
  71     unsigned long sc_esi;
  72     unsigned long sc_ebp;
  73     unsigned long sc_esp;
  74     unsigned long sc_ebx;
  75     unsigned long sc_edx;
  76     unsigned long sc_ecx;
  77     unsigned long sc_eax;
  78     unsigned long sc_trapno;
  79     unsigned long sc_err;
  80     unsigned long sc_eip;
  81     unsigned short sc_cs, __csh;
  82     unsigned long sc_eflags;
  83     unsigned long esp_at_signal;
  84     unsigned short sc_ss, __ssh;
  85     unsigned long i387;
  86     unsigned long oldmask;
  87     unsigned long cr2;
  88 } SIGCONTEXT;
  89
  90 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  91 #define HANDLER_CONTEXT (&__context)
  92
  93 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  94 struct kernel_sigaction
  95 {
  96     void (*ksa_handler)();
  97     unsigned long ksa_mask;
  98     unsigned long ksa_flags;
  99     void *ksa_restorer;
 100 };
 101
 102 /* Similar to the sigaction function in libc, except it leaves alone the
 103    restorer field, which is used to specify the signal stack address */
 104 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
 105                                   struct kernel_sigaction *old )
 106 {
 107     __asm__ __volatile__( "pushl %%ebx\n\t"
 108                           "movl %2,%%ebx\n\t"
 109                           "int $0x80\n\t"
 110                           "popl %%ebx"
 111                           : "=a" (sig)
 112                           : "0" (SYS_sigaction), "S" (sig), "c" (new), "d" (old) );
 113     if (sig>=0) return 0;
 114     errno = -sig;
 115     return -1;
 116 }
 117
 118 #ifdef HAVE_SIGALTSTACK
 119 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
 120 static inline int wine_sigaltstack( const struct sigaltstack *new,
 121                                     struct sigaltstack *old )
 122 {
 123     int ret;
 124     __asm__ __volatile__( "pushl %%ebx\n\t"
 125                           "movl %2,%%ebx\n\t"
 126                           "int $0x80\n\t"
 127                           "popl %%ebx"
 128                           : "=a" (ret)
 129                           : "0" (SYS_sigaltstack), "q" (new), "c" (old) );
 130     if (ret >= 0) return 0;
 131     errno = -ret;
 132     return -1;
 133 }
 134 #endif
 135
 136 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 137
 138 int vm86_enter( void **vm86_ptr );
 139 void vm86_return(void);
 140 void vm86_return_end(void);
 141 __ASM_GLOBAL_FUNC(vm86_enter,
 142                   "pushl %ebp\n\t"
 143                   "movl %esp, %ebp\n\t"
 144                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 145                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 146                   "movl (%ecx),%ecx\n\t"
 147                   "pushl %ebx\n\t"
 148                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 149                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 150                   "pushl %fs\n\t"
 151                   "pushl %gs\n\t"
 152                   "int $0x80\n"
 153                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 154                   __ASM_FUNC("vm86_return") "\n"
 155                   __ASM_NAME("vm86_return") ":\n\t"
 156                   "popl %gs\n\t"
 157                   "popl %fs\n\t"
 158                   "popl %ecx\n\t"
 159                   "popl %ebx\n\t"
 160                   "popl %ebp\n\t"
 161                   "testl %eax,%eax\n\t"
 162                   "jl 0f\n\t"
 163                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 164                   "je " __ASM_NAME("vm86_enter") "\n\t"
 165                   "0:\n\t"
 166                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 167                   "movl $0,(%ecx)\n\t"
 168                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 169                   __ASM_FUNC("vm86_return_end") "\n"
 170                   __ASM_NAME("vm86_return_end") ":\n\t"
 171                   "ret" );
 172
 173 #ifdef HAVE_SYS_VM86_H
 174 # define __HAVE_VM86
 175 #endif
 176
 177 #endif  /* linux */
 178
 179 #ifdef BSDI
 180
 181 #define EAX_sig(context)     ((context)->tf_eax)
 182 #define EBX_sig(context)     ((context)->tf_ebx)
 183 #define ECX_sig(context)     ((context)->tf_ecx)
 184 #define EDX_sig(context)     ((context)->tf_edx)
 185 #define ESI_sig(context)     ((context)->tf_esi)
 186 #define EDI_sig(context)     ((context)->tf_edi)
 187 #define EBP_sig(context)     ((context)->tf_ebp)
 188
 189 #define CS_sig(context)      ((context)->tf_cs)
 190 #define DS_sig(context)      ((context)->tf_ds)
 191 #define ES_sig(context)      ((context)->tf_es)
 192 #define SS_sig(context)      ((context)->tf_ss)
 193
 194 #include <machine/frame.h>
 195 typedef struct trapframe SIGCONTEXT;
 196
 197 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 198 #define HANDLER_CONTEXT __context
 199
 200 #define EFL_sig(context)     ((context)->tf_eflags)
 201
 202 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 203 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 204
 205 #endif /* bsdi */
 206
 207 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 208
 209 typedef struct sigcontext SIGCONTEXT;
 210
 211 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 212 #define HANDLER_CONTEXT __context
 213
 214 #endif  /* *BSD */
 215
 216 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 217
 218 #ifdef _SCO_DS
 219 #include <sys/regset.h>
 220 #endif
 221 /* Solaris kludge */
 222 #undef ERR
 223 #include <sys/ucontext.h>
 224 #undef ERR
 225 typedef struct ucontext SIGCONTEXT;
 226
 227 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 228 #define HANDLER_CONTEXT __context
 229
 230 #endif  /* svr4 || SCO_DS */
 231
 232 #ifdef __EMX__
 233
 234 typedef struct
 235 {
 236     unsigned long ContextFlags;
 237     FLOATING_SAVE_AREA sc_float;
 238     unsigned long sc_gs;
 239     unsigned long sc_fs;
 240     unsigned long sc_es;
 241     unsigned long sc_ds;
 242     unsigned long sc_edi;
 243     unsigned long sc_esi;
 244     unsigned long sc_eax;
 245     unsigned long sc_ebx;
 246     unsigned long sc_ecx;
 247     unsigned long sc_edx;
 248     unsigned long sc_ebp;
 249     unsigned long sc_eip;
 250     unsigned long sc_cs;
 251     unsigned long sc_eflags;
 252     unsigned long sc_esp;
 253     unsigned long sc_ss;
 254 } SIGCONTEXT;
 255
 256 #endif  /* __EMX__ */
 257
 258 #ifdef __CYGWIN__
 259
 260 /* FIXME: This section is just here so it can compile, it's most likely
 261  * completely wrong. */
 262
 263 typedef struct
 264 {
 265     unsigned short sc_gs, __gsh;
 266     unsigned short sc_fs, __fsh;
 267     unsigned short sc_es, __esh;
 268     unsigned short sc_ds, __dsh;
 269     unsigned long sc_edi;
 270     unsigned long sc_esi;
 271     unsigned long sc_ebp;
 272     unsigned long sc_esp;
 273     unsigned long sc_ebx;
 274     unsigned long sc_edx;
 275     unsigned long sc_ecx;
 276     unsigned long sc_eax;
 277     unsigned long sc_trapno;
 278     unsigned long sc_err;
 279     unsigned long sc_eip;
 280     unsigned short sc_cs, __csh;
 281     unsigned long sc_eflags;
 282     unsigned long esp_at_signal;
 283     unsigned short sc_ss, __ssh;
 284     unsigned long i387;
 285     unsigned long oldmask;
 286     unsigned long cr2;
 287 } SIGCONTEXT;
 288
 289 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
 290 #define HANDLER_CONTEXT (&__context)
 291
 292 #endif /* __CYGWIN__ */
 293
 294 #ifdef __APPLE__
 295 # include <sys/ucontext.h>
 296 # include <sys/types.h>
 297 # include <signal.h>
 298
 299 typedef siginfo_t siginfo;
 300 typedef struct sigcontext SIGCONTEXT;
 301
 302 #define EAX_sig(context)     ((context)->sc_eax)
 303 #define EBX_sig(context)     ((context)->sc_ebx)
 304 #define ECX_sig(context)     ((context)->sc_ecx)
 305 #define EDX_sig(context)     ((context)->sc_edx)
 306 #define ESI_sig(context)     ((context)->sc_esi)
 307 #define EDI_sig(context)     ((context)->sc_edi)
 308 #define EBP_sig(context)     ((context)->sc_ebp)
 309
 310 #define CS_sig(context)      ((context)->sc_cs)
 311 #define DS_sig(context)      ((context)->sc_ds)
 312 #define ES_sig(context)      ((context)->sc_es)
 313 #define FS_sig(context)      ((context)->sc_fs)
 314 #define GS_sig(context)      ((context)->sc_gs)
 315 #define SS_sig(context)      ((context)->sc_ss)
 316
 317 #define EFL_sig(context)     ((context)->sc_eflags)
 318
 319 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 320 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 321
 322 # define HANDLER_DEF(name) void name( int __signal, siginfo *__siginfo, SIGCONTEXT *__context )
 323 # define HANDLER_CONTEXT (__context)
 324
 325 #endif /* __APPLE__ */
 326
 327 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) ||\
 328     defined(__OpenBSD__) || defined(__EMX__) || defined(__CYGWIN__)
 329
 330 #define EAX_sig(context)     ((context)->sc_eax)
 331 #define EBX_sig(context)     ((context)->sc_ebx)
 332 #define ECX_sig(context)     ((context)->sc_ecx)
 333 #define EDX_sig(context)     ((context)->sc_edx)
 334 #define ESI_sig(context)     ((context)->sc_esi)
 335 #define EDI_sig(context)     ((context)->sc_edi)
 336 #define EBP_sig(context)     ((context)->sc_ebp)
 337
 338 #define CS_sig(context)      ((context)->sc_cs)
 339 #define DS_sig(context)      ((context)->sc_ds)
 340 #define ES_sig(context)      ((context)->sc_es)
 341 #define FS_sig(context)      ((context)->sc_fs)
 342 #define GS_sig(context)      ((context)->sc_gs)
 343 #define SS_sig(context)      ((context)->sc_ss)
 344
 345 #define TRAP_sig(context)    ((context)->sc_trapno)
 346
 347 #ifdef __NetBSD__
 348 #define ERROR_sig(context)   ((context)->sc_err)
 349 #endif
 350
 351 #ifdef linux
 352 #define ERROR_sig(context)   ((context)->sc_err)
 353 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 354 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->cr2)
 355 #endif
 356
 357 #ifdef __FreeBSD__
 358 #define EFL_sig(context)     ((context)->sc_efl)
 359 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 360 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->sc_err)
 361 #else
 362 #define EFL_sig(context)     ((context)->sc_eflags)
 363 #endif
 364
 365 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 366 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 367
 368 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 369
 370 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 371
 372 #ifdef _SCO_DS
 373 #define gregs regs
 374 #endif
 375
 376 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 377 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 378 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 379 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 380 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 381 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 382 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 383
 384 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 385 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 386 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 387 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 388
 389 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 390 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 391
 392 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 393
 394 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 395 #ifdef UESP
 396 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 397 #elif defined(R_ESP)
 398 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 399 #else
 400 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 401 #endif
 402 #ifdef TRAPNO
 403 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 404 #endif
 405
 406 #define FAULT_ADDRESS         (__siginfo->si_addr)
 407
 408 #endif  /* svr4 || SCO_DS */
 409
 410 /* exception code definitions (already defined by FreeBSD/NetBSD) */
 411 #if !defined(__FreeBSD__) && !defined(__NetBSD__) /* FIXME: other BSDs? */
 412 #define T_DIVIDE        0   /* Division by zero exception */
 413 #define T_TRCTRAP       1   /* Single-step exception */
 414 #define T_NMI           2   /* NMI interrupt */
 415 #define T_BPTFLT        3   /* Breakpoint exception */
 416 #define T_OFLOW         4   /* Overflow exception */
 417 #define T_BOUND         5   /* Bound range exception */
 418 #define T_PRIVINFLT     6   /* Invalid opcode exception */
 419 #define T_DNA           7   /* Device not available exception */
 420 #define T_DOUBLEFLT     8   /* Double fault exception */
 421 #define T_FPOPFLT       9   /* Coprocessor segment overrun */
 422 #define T_TSSFLT        10  /* Invalid TSS exception */
 423 #define T_SEGNPFLT      11  /* Segment not present exception */
 424 #define T_STKFLT        12  /* Stack fault */
 425 #define T_PROTFLT       13  /* General protection fault */
 426 #define T_PAGEFLT       14  /* Page fault */
 427 #define T_RESERVED      15  /* Unknown exception */
 428 #define T_ARITHTRAP     16  /* Floating point exception */
 429 #define T_ALIGNFLT      17  /* Alignment check exception */
 430 #define T_MCHK          18  /* Machine check exception */
 431 #define T_CACHEFLT      19  /* Cache flush exception */
 432 #endif
 433 #if defined(__NetBSD__)
 434 #define T_MCHK          19  /* Machine check exception */
 435 #endif
 436
 437 #define T_UNKNOWN     (-1)  /* Unknown fault (TRAP_sig not defined) */
 438
 439 #include "wine/exception.h"
 440 #include "wine/debug.h"
 441
 442 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 443
 444 typedef int (*wine_signal_handler)(unsigned int sig);
 445
 446 static wine_signal_handler handlers[256];
 447
 448 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( CONTEXT context );
 449
 450
 451 /***********************************************************************
 452  *           dispatch_signal
 453  */
 454 inline static int dispatch_signal(unsigned int sig)
 455 {
 456     if (handlers[sig] == NULL) return 0;
 457     return handlers[sig](sig);
 458 }
 459
 460
 461 /***********************************************************************
 462  *           get_trap_code
 463  *
 464  * Get the trap code for a signal.
 465  */
 466 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 467 {
 468 #ifdef TRAP_sig
 469     return TRAP_sig(sigcontext);
 470 #else
 471     return T_UNKNOWN;  /* unknown trap code */
 472 #endif
 473 }
 474
 475 /***********************************************************************
 476  *           get_error_code
 477  *
 478  * Get the error code for a signal.
 479  */
 480 static inline int get_error_code( const SIGCONTEXT *sigcontext )
 481 {
 482 #ifdef ERROR_sig
 483     return ERROR_sig(sigcontext);
 484 #else
 485     return 0;
 486 #endif
 487 }
 488
 489 /***********************************************************************
 490  *           get_signal_stack
 491  *
 492  * Get the base of the signal stack for the current thread.
 493  */
 494 static inline void *get_signal_stack(void)
 495 {
 496     return (char *)NtCurrentTeb() + 4096;
 497 }
 498
 499
 500 /***********************************************************************
 501  *           get_current_teb
 502  *
 503  * Get the current teb based on the stack pointer.
 504  */
 505 static inline TEB *get_current_teb(void)
 506 {
 507     unsigned long esp;
 508     __asm__("movl %%esp,%0" : "=g" (esp) );
 509     return (TEB *)((esp & ~4095) - 4096);
 510 }
 511
 512
 513 #ifdef __HAVE_VM86
 514 /***********************************************************************
 515  *           save_vm86_context
 516  *
 517  * Set the register values from a vm86 structure.
 518  */
 519 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 520 {
 521     context->Eax    = vm86->regs.eax;
 522     context->Ebx    = vm86->regs.ebx;
 523     context->Ecx    = vm86->regs.ecx;
 524     context->Edx    = vm86->regs.edx;
 525     context->Esi    = vm86->regs.esi;
 526     context->Edi    = vm86->regs.edi;
 527     context->Esp    = vm86->regs.esp;
 528     context->Ebp    = vm86->regs.ebp;
 529     context->Eip    = vm86->regs.eip;
 530     context->SegCs  = vm86->regs.cs;
 531     context->SegDs  = vm86->regs.ds;
 532     context->SegEs  = vm86->regs.es;
 533     context->SegFs  = vm86->regs.fs;
 534     context->SegGs  = vm86->regs.gs;
 535     context->SegSs  = vm86->regs.ss;
 536     context->EFlags = vm86->regs.eflags;
 537 }
 538
 539
 540 /***********************************************************************
 541  *           restore_vm86_context
 542  *
 543  * Build a vm86 structure from the register values.
 544  */
 545 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 546 {
 547     vm86->regs.eax    = context->Eax;
 548     vm86->regs.ebx    = context->Ebx;
 549     vm86->regs.ecx    = context->Ecx;
 550     vm86->regs.edx    = context->Edx;
 551     vm86->regs.esi    = context->Esi;
 552     vm86->regs.edi    = context->Edi;
 553     vm86->regs.esp    = context->Esp;
 554     vm86->regs.ebp    = context->Ebp;
 555     vm86->regs.eip    = context->Eip;
 556     vm86->regs.cs     = context->SegCs;
 557     vm86->regs.ds     = context->SegDs;
 558     vm86->regs.es     = context->SegEs;
 559     vm86->regs.fs     = context->SegFs;
 560     vm86->regs.gs     = context->SegGs;
 561     vm86->regs.ss     = context->SegSs;
 562     vm86->regs.eflags = context->EFlags;
 563 }
 564
 565
 566 /**********************************************************************
 567  *              merge_vm86_pending_flags
 568  *
 569  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 570  * raises exception if there are pending events and VIF flag
 571  * has been turned on.
 572  *
 573  * Called from __wine_enter_vm86 because vm86_enter
 574  * doesn't check for pending events.
 575  *
 576  * Called from raise_vm86_sti_exception to check for
 577  * pending events in a signal safe way.
 578  */
 579 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 580 {
 581     BOOL check_pending = TRUE;
 582     struct vm86plus_struct *vm86 =
 583         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 584
 585     /*
 586      * In order to prevent a race when SIGUSR2 occurs while
 587      * we are returning from exception handler, pending events
 588      * will be rechecked after each raised exception.
 589      */
 590     while (check_pending && NtCurrentTeb()->vm86_pending)
 591     {
 592         check_pending = FALSE;
 593         ntdll_get_thread_data()->vm86_ptr = NULL;
 594
 595         /*
 596          * If VIF is set, throw exception.
 597          * Note that SIGUSR2 may turn VIF flag off so
 598          * VIF check must occur only when TEB.vm86_ptr is NULL.
 599          */
 600         if (vm86->regs.eflags & VIF_MASK)
 601         {
 602             CONTEXT vcontext;
 603             save_vm86_context( &vcontext, vm86 );
 604
 605             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 606             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 607             rec->ExceptionRecord  = NULL;
 608             rec->NumberParameters = 0;
 609             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 610
 611             vcontext.EFlags &= ~VIP_MASK;
 612             NtCurrentTeb()->vm86_pending = 0;
 613             __regs_RtlRaiseException( rec, &vcontext );
 614
 615             restore_vm86_context( &vcontext, vm86 );
 616             check_pending = TRUE;
 617         }
 618
 619         ntdll_get_thread_data()->vm86_ptr = vm86;
 620     }
 621
 622     /*
 623      * Merge VIP flags in a signal safe way. This requires
 624      * that the following operation compiles into atomic
 625      * instruction.
 626      */
 627     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 628 }
 629 #endif /* __HAVE_VM86 */
 630
 631
 632 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 633
 634
 635 /***********************************************************************
 636  *           init_handler
 637  *
 638  * Handler initialization when the full context is not needed.
 639  */
 640 static void *init_handler( const SIGCONTEXT *sigcontext )
 641 {
 642     void *stack = (void *)ESP_sig(sigcontext);
 643     TEB *teb = get_current_teb();
 644     struct ntdll_thread_data *thread_data = (struct ntdll_thread_data *)teb->SystemReserved2;
 645
 646     wine_set_fs( thread_data->teb_sel );
 647
 648     /* now restore a proper %gs for the fault handler */
 649     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 650         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 651     {
 652         /*
 653          * Win16 or DOS protected mode. Note that during switch
 654          * from 16-bit mode to linear mode, CS may be set to system
 655          * segment before FS is restored. Fortunately, in this case
 656          * SS is still non-system segment. This is why both CS and SS
 657          * are checked.
 658          */
 659         wine_set_gs( teb->gs_sel );
 660         stack = teb->WOW32Reserved;
 661     }
 662 #ifdef __HAVE_VM86
 663     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 664     {
 665         unsigned int *int_stack = stack;
 666         /* fetch the saved %gs from the stack */
 667         wine_set_gs( int_stack[0] );
 668     }
 669 #endif
 670     else  /* 32-bit mode */
 671     {
 672 #ifdef GS_sig
 673         wine_set_gs( GS_sig(sigcontext) );
 674 #endif
 675     }
 676     return stack;
 677 }
 678
 679
 680 /***********************************************************************
 681  *           save_fpu
 682  *
 683  * Set the FPU context from a sigcontext.
 684  */
 685 inline static void save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 686 {
 687 #ifdef FPU_sig
 688     if (FPU_sig(sigcontext))
 689     {
 690         context->FloatSave = *FPU_sig(sigcontext);
 691         return;
 692     }
 693 #endif  /* FPU_sig */
 694 #ifdef __GNUC__
 695     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 696 #endif  /* __GNUC__ */
 697 }
 698
 699
 700 /***********************************************************************
 701  *           restore_fpu
 702  *
 703  * Restore the FPU context to a sigcontext.
 704  */
 705 inline static void restore_fpu( CONTEXT *context )
 706 {
 707     /* reset the current interrupt status */
 708     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 709 #ifdef __GNUC__
 710     /* avoid nested exceptions */
 711     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 712 #endif  /* __GNUC__ */
 713 }
 714
 715
 716 /***********************************************************************
 717  *           setup_exception
 718  *
 719  * Setup a proper stack frame for the raise function, and modify the
 720  * sigcontext so that the return from the signal handler will call
 721  * the raise function.
 722  */
 723 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 724 {
 725     struct stack_layout
 726     {
 727         void             *ret_addr;      /* return address from raise_func */
 728         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 729         CONTEXT          *context_ptr;   /* second arg for raise_func */
 730         void             *dummy;         /* dummy ret addr for __wine_call_from_32_restore_regs */
 731         CONTEXT           context;
 732         EXCEPTION_RECORD  rec;
 733         DWORD             ebp;
 734         DWORD             eip;
 735     } *stack;
 736
 737     WORD fs, gs;
 738
 739     /* get %fs and %gs at time of the fault */
 740 #ifdef FS_sig
 741     fs = LOWORD(FS_sig(sigcontext));
 742 #else
 743     fs = wine_get_fs();
 744 #endif
 745 #ifdef GS_sig
 746     gs = LOWORD(GS_sig(sigcontext));
 747 #else
 748     gs = wine_get_gs();
 749 #endif
 750
 751     stack = init_handler( sigcontext );
 752
 753     /* stack sanity checks */
 754
 755     if ((char *)stack >= (char *)get_signal_stack() &&
 756         (char *)stack < (char *)get_signal_stack() + SIGNAL_STACK_SIZE)
 757     {
 758         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 759              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 760              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 761         server_abort_thread(1);
 762     }
 763
 764     if ((char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit + 4096 ||
 765         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 766     {
 767         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit + 4096 - (char *)stack;
 768         if (diff < 4096)
 769         {
 770             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 771                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 772                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 773             server_abort_thread(1);
 774         }
 775         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 776                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 777                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 778     }
 779
 780     stack--;  /* push the stack_layout structure */
 781     stack->ret_addr     = __wine_call_from_32_restore_regs;
 782     stack->rec_ptr      = &stack->rec;
 783     stack->context_ptr  = &stack->context;
 784
 785     stack->rec.ExceptionRecord  = NULL;
 786     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 787     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 788     stack->rec.NumberParameters = 0;
 789
 790     stack->context.ContextFlags = CONTEXT_FULL;
 791     stack->context.Eax          = EAX_sig(sigcontext);
 792     stack->context.Ebx          = EBX_sig(sigcontext);
 793     stack->context.Ecx          = ECX_sig(sigcontext);
 794     stack->context.Edx          = EDX_sig(sigcontext);
 795     stack->context.Esi          = ESI_sig(sigcontext);
 796     stack->context.Edi          = EDI_sig(sigcontext);
 797     stack->context.Ebp          = EBP_sig(sigcontext);
 798     stack->context.EFlags       = EFL_sig(sigcontext);
 799     stack->context.Eip          = EIP_sig(sigcontext);
 800     stack->context.Esp          = ESP_sig(sigcontext);
 801     stack->context.SegCs        = LOWORD(CS_sig(sigcontext));
 802     stack->context.SegDs        = LOWORD(DS_sig(sigcontext));
 803     stack->context.SegEs        = LOWORD(ES_sig(sigcontext));
 804     stack->context.SegFs        = fs;
 805     stack->context.SegGs        = gs;
 806     stack->context.SegSs        = LOWORD(SS_sig(sigcontext));
 807
 808     /* now modify the sigcontext to return to the raise function */
 809     ESP_sig(sigcontext) = (DWORD)stack;
 810     EIP_sig(sigcontext) = (DWORD)func;
 811     CS_sig(sigcontext)  = wine_get_cs();
 812     DS_sig(sigcontext)  = wine_get_ds();
 813     ES_sig(sigcontext)  = wine_get_es();
 814     FS_sig(sigcontext)  = wine_get_fs();
 815     GS_sig(sigcontext)  = wine_get_gs();
 816     SS_sig(sigcontext)  = wine_get_ss();
 817
 818     return stack->rec_ptr;
 819 }
 820
 821
 822 /***********************************************************************
 823  *           get_exception_context
 824  *
 825  * Get a pointer to the context built by setup_exception.
 826  */
 827 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 828 {
 829     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 830 }
 831
 832
 833 /**********************************************************************
 834  *              get_fpu_code
 835  *
 836  * Get the FPU exception code from the FPU status.
 837  */
 838 static inline DWORD get_fpu_code( const CONTEXT *context )
 839 {
 840     DWORD status = context->FloatSave.StatusWord;
 841
 842     if (status & 0x01)  /* IE */
 843     {
 844         if (status & 0x40)  /* SF */
 845             return EXCEPTION_FLT_STACK_CHECK;
 846         else
 847             return EXCEPTION_FLT_INVALID_OPERATION;
 848     }
 849     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 850     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 851     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 852     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 853     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 854     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 855 }
 856
 857
 858 /**********************************************************************
 859  *              raise_segv_exception
 860  */
 861 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 862 {
 863     switch(rec->ExceptionCode)
 864     {
 865     case EXCEPTION_ACCESS_VIOLATION:
 866         if (rec->NumberParameters == 2)
 867         {
 868             if (!(rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] )))
 869                 return;
 870         }
 871         break;
 872     case EXCEPTION_DATATYPE_MISALIGNMENT:
 873         /* FIXME: pass through exception handler first? */
 874         if (context->EFlags & 0x00040000)
 875         {
 876             /* Disable AC flag, return */
 877             context->EFlags &= ~0x00040000;
 878             return;
 879         }
 880         break;
 881     }
 882     __regs_RtlRaiseException( rec, context );
 883 }
 884
 885
 886 /**********************************************************************
 887  *              raise_trap_exception
 888  */
 889 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 890 {
 891     DWORD dr0, dr1, dr2, dr3, dr6, dr7;
 892
 893     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
 894     {
 895         if (context->EFlags & 0x100)
 896         {
 897             context->EFlags &= ~0x100;  /* clear single-step flag */
 898         }
 899         else  /* hardware breakpoint, fetch the debug registers */
 900         {
 901             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
 902             NtGetContextThread(GetCurrentThread(), context);
 903             /* do we really have a bp from a debug register ?
 904              * if not, then someone did a kill(SIGTRAP) on us, and we
 905              * shall return a breakpoint, not a single step exception
 906              */
 907             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
 908         }
 909     }
 910
 911     dr0 = context->Dr0;
 912     dr1 = context->Dr1;
 913     dr2 = context->Dr2;
 914     dr3 = context->Dr3;
 915     dr6 = context->Dr6;
 916     dr7 = context->Dr7;
 917
 918     __regs_RtlRaiseException( rec, context );
 919
 920     if (dr0 != context->Dr0 || dr1 != context->Dr1 || dr2 != context->Dr2 ||
 921         dr3 != context->Dr3 || dr6 != context->Dr6 || dr7 != context->Dr7)
 922     {
 923         /* the debug registers have changed, set the new values */
 924         context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
 925         NtSetContextThread(GetCurrentThread(), context);
 926     }
 927 }
 928
 929
 930 /**********************************************************************
 931  *              raise_fpu_exception
 932  */
 933 static void WINAPI raise_fpu_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 934 {
 935     __regs_RtlRaiseException( rec, context );
 936     restore_fpu( context );
 937 }
 938
 939
 940 #ifdef __HAVE_VM86
 941 /**********************************************************************
 942  *              raise_vm86_sti_exception
 943  */
 944 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 945 {
 946     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
 947     NtCurrentTeb()->vm86_pending |= VIP_MASK;
 948
 949     if (ntdll_get_thread_data()->vm86_ptr)
 950     {
 951         if (((char*)context->Eip >= (char*)vm86_return) &&
 952             ((char*)context->Eip <= (char*)vm86_return_end) &&
 953             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
 954             /* exiting from VM86, can't throw */
 955             return;
 956         }
 957         merge_vm86_pending_flags( rec );
 958     }
 959     else if (NtCurrentTeb()->dpmi_vif &&
 960              !wine_ldt_is_system(context->SegCs) &&
 961              !wine_ldt_is_system(context->SegSs))
 962     {
 963         /* Executing DPMI code and virtual interrupts are enabled. */
 964         NtCurrentTeb()->vm86_pending = 0;
 965         __regs_RtlRaiseException( rec, context );
 966     }
 967 }
 968
 969
 970 /**********************************************************************
 971  *              usr2_handler
 972  *
 973  * Handler for SIGUSR2.
 974  * We use it to signal that the running __wine_enter_vm86() should
 975  * immediately set VIP_MASK, causing pending events to be handled
 976  * as early as possible.
 977  */
 978 static HANDLER_DEF(usr2_handler)
 979 {
 980     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
 981     rec->ExceptionCode = EXCEPTION_VM86_STI;
 982 }
 983 #endif /* __HAVE_VM86 */
 984
 985
 986 /**********************************************************************
 987  *              segv_handler
 988  *
 989  * Handler for SIGSEGV and related errors.
 990  */
 991 static HANDLER_DEF(segv_handler)
 992 {
 993     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
 994
 995     switch(get_trap_code(HANDLER_CONTEXT))
 996     {
 997     case T_OFLOW:   /* Overflow exception */
 998         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
 999         break;
1000     case T_BOUND:   /* Bound range exception */
1001         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1002         break;
1003     case T_PRIVINFLT:   /* Invalid opcode exception */
1004         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1005         break;
1006     case T_STKFLT:  /* Stack fault */
1007         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1008         break;
1009     case T_SEGNPFLT:  /* Segment not present exception */
1010     case T_PROTFLT:   /* General protection fault */
1011     case T_UNKNOWN:   /* Unknown fault code */
1012         rec->ExceptionCode = get_error_code(HANDLER_CONTEXT) ? EXCEPTION_ACCESS_VIOLATION
1013                                                              : EXCEPTION_PRIV_INSTRUCTION;
1014         break;
1015     case T_PAGEFLT:  /* Page fault */
1016         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1017 #ifdef FAULT_ADDRESS
1018         rec->NumberParameters = 2;
1019         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) & 2) != 0;
1020         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1021 #endif
1022         break;
1023     case T_ALIGNFLT:  /* Alignment check exception */
1024         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1025         break;
1026     default:
1027         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1028         /* fall through */
1029     case T_NMI:       /* NMI interrupt */
1030     case T_DNA:       /* Device not available exception */
1031     case T_DOUBLEFLT: /* Double fault exception */
1032     case T_TSSFLT:    /* Invalid TSS exception */
1033     case T_RESERVED:  /* Unknown exception */
1034     case T_MCHK:      /* Machine check exception */
1035 #ifdef T_CACHEFLT
1036     case T_CACHEFLT:  /* Cache flush exception */
1037 #endif
1038         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1039         break;
1040     }
1041 }
1042
1043
1044 /**********************************************************************
1045  *              trap_handler
1046  *
1047  * Handler for SIGTRAP.
1048  */
1049 static HANDLER_DEF(trap_handler)
1050 {
1051     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1052
1053     switch(get_trap_code(HANDLER_CONTEXT))
1054     {
1055     case T_TRCTRAP:  /* Single-step exception */
1056         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1057         EFL_sig(HANDLER_CONTEXT) &= ~0x100;  /* clear single-step flag */
1058         break;
1059     case T_BPTFLT:   /* Breakpoint exception */
1060         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1061         /* fall through */
1062     default:
1063         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1064         break;
1065     }
1066 }
1067
1068
1069 /**********************************************************************
1070  *              fpe_handler
1071  *
1072  * Handler for SIGFPE.
1073  */
1074 static HANDLER_DEF(fpe_handler)
1075 {
1076     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_fpu_exception );
1077     CONTEXT *context;
1078
1079     context = get_exception_context( rec );
1080     save_fpu( context, HANDLER_CONTEXT );
1081
1082     switch(get_trap_code(HANDLER_CONTEXT))
1083     {
1084     case T_DIVIDE:   /* Division by zero exception */
1085         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1086         break;
1087     case T_FPOPFLT:   /* Coprocessor segment overrun */
1088         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1089         break;
1090     case T_ARITHTRAP:  /* Floating point exception */
1091     case T_UNKNOWN:    /* Unknown fault code */
1092         rec->ExceptionCode = get_fpu_code( context );
1093         break;
1094     default:
1095         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1096         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1097         break;
1098     }
1099 }
1100
1101
1102 /**********************************************************************
1103  *              int_handler
1104  *
1105  * Handler for SIGINT.
1106  */
1107 static HANDLER_DEF(int_handler)
1108 {
1109     init_handler( HANDLER_CONTEXT );
1110     if (!dispatch_signal(SIGINT))
1111     {
1112         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1113         rec->ExceptionCode = CONTROL_C_EXIT;
1114     }
1115 }
1116
1117 /**********************************************************************
1118  *              abrt_handler
1119  *
1120  * Handler for SIGABRT.
1121  */
1122 static HANDLER_DEF(abrt_handler)
1123 {
1124     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1125     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1126     rec->ExceptionFlags = EH_NONCONTINUABLE;
1127 }
1128
1129
1130 /**********************************************************************
1131  *              term_handler
1132  *
1133  * Handler for SIGTERM.
1134  */
1135 static HANDLER_DEF(term_handler)
1136 {
1137     init_handler( HANDLER_CONTEXT );
1138     server_abort_thread(0);
1139 }
1140
1141
1142 /**********************************************************************
1143  *              usr1_handler
1144  *
1145  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1146  */
1147 static HANDLER_DEF(usr1_handler)
1148 {
1149     LARGE_INTEGER timeout;
1150
1151     init_handler( HANDLER_CONTEXT );
1152     /* wait with 0 timeout, will only return once the thread is no longer suspended */
1153     timeout.QuadPart = 0;
1154     NTDLL_wait_for_multiple_objects( 0, NULL, 0, &timeout, 0 );
1155 }
1156
1157
1158 /***********************************************************************
1159  *           set_handler
1160  *
1161  * Set a signal handler
1162  */
1163 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1164 {
1165     struct sigaction sig_act;
1166
1167 #ifdef linux
1168     if (!have_sigaltstack)
1169     {
1170         struct kernel_sigaction sig_act;
1171         sig_act.ksa_handler = func;
1172         sig_act.ksa_flags   = SA_RESTART;
1173         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1174                               (1 << (SIGUSR2-1));
1175         /* point to the top of the signal stack */
1176         sig_act.ksa_restorer = (char *)get_signal_stack() + SIGNAL_STACK_SIZE;
1177         return wine_sigaction( sig, &sig_act, NULL );
1178     }
1179 #endif  /* linux */
1180     sig_act.sa_handler = func;
1181     sigemptyset( &sig_act.sa_mask );
1182     sigaddset( &sig_act.sa_mask, SIGINT );
1183     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1184
1185 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
1186     sig_act.sa_flags = SA_RESTART;
1187 #elif defined (__svr4__) || defined(_SCO_DS)
1188     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1189 #else
1190     sig_act.sa_flags = 0;
1191 #endif
1192
1193 #ifdef SA_ONSTACK
1194     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1195 #endif
1196     return sigaction( sig, &sig_act, NULL );
1197 }
1198
1199
1200 /***********************************************************************
1201  *           __wine_set_signal_handler   (NTDLL.@)
1202  */
1203 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1204 {
1205     if (sig > sizeof(handlers) / sizeof(handlers[0])) return -1;
1206     if (handlers[sig] != NULL) return -2;
1207     handlers[sig] = wsh;
1208     return 0;
1209 }
1210
1211
1212 /**********************************************************************
1213  *              SIGNAL_Init
1214  */
1215 BOOL SIGNAL_Init(void)
1216 {
1217     int have_sigaltstack = 0;
1218
1219 #ifdef HAVE_SIGALTSTACK
1220     struct sigaltstack ss;
1221     ss.ss_sp    = get_signal_stack();
1222     ss.ss_size  = SIGNAL_STACK_SIZE;
1223     ss.ss_flags = 0;
1224     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1225 #ifdef linux
1226     /* sigaltstack may fail because the kernel is too old, or
1227        because glibc is brain-dead. In the latter case a
1228        direct system call should succeed. */
1229     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1230 #endif  /* linux */
1231 #endif  /* HAVE_SIGALTSTACK */
1232
1233     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1234     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1235     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1236     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1237     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1238     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1239     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1240 #ifdef SIGBUS
1241     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1242 #endif
1243 #ifdef SIGTRAP
1244     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1245 #endif
1246
1247 #ifdef __HAVE_VM86
1248     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1249 #endif
1250
1251     return TRUE;
1252
1253  error:
1254     perror("sigaction");
1255     return FALSE;
1256 }
1257
1258
1259 #ifdef __HAVE_VM86
1260 /**********************************************************************
1261  *              __wine_enter_vm86   (NTDLL.@)
1262  *
1263  * Enter vm86 mode with the specified register context.
1264  */
1265 void __wine_enter_vm86( CONTEXT *context )
1266 {
1267     EXCEPTION_RECORD rec;
1268     int res;
1269     struct vm86plus_struct vm86;
1270
1271     memset( &vm86, 0, sizeof(vm86) );
1272     for (;;)
1273     {
1274         restore_vm86_context( context, &vm86 );
1275
1276         ntdll_get_thread_data()->vm86_ptr = &vm86;
1277         merge_vm86_pending_flags( &rec );
1278
1279         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1280         if (res < 0)
1281         {
1282             errno = -res;
1283             return;
1284         }
1285
1286         save_vm86_context( context, &vm86 );
1287
1288         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1289         rec.ExceptionRecord  = NULL;
1290         rec.ExceptionAddress = (LPVOID)context->Eip;
1291         rec.NumberParameters = 0;
1292
1293         switch(VM86_TYPE(res))
1294         {
1295         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1296             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1297             raise_segv_exception( &rec, context );
1298             continue;
1299         case VM86_TRAP: /* return due to DOS-debugger request */
1300             switch(VM86_ARG(res))
1301             {
1302             case T_TRCTRAP:  /* Single-step exception, single step flag is cleared by raise_trap_exception */
1303                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1304                 break;
1305             case T_BPTFLT:   /* Breakpoint exception */
1306                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1307                 /* fall through */
1308             default:
1309                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1310                 break;
1311             }
1312             raise_trap_exception( &rec, context );
1313             continue;
1314         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1315             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1316             rec.NumberParameters = 1;
1317             rec.ExceptionInformation[0] = VM86_ARG(res);
1318             break;
1319         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1320             context->EFlags |= VIF_MASK;
1321             context->EFlags &= ~VIP_MASK;
1322             NtCurrentTeb()->vm86_pending = 0;
1323             rec.ExceptionCode = EXCEPTION_VM86_STI;
1324             break;
1325         case VM86_PICRETURN: /* return due to pending PIC request */
1326             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1327             break;
1328         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1329         default:
1330             ERR( "unhandled result from vm86 mode %x\n", res );
1331             continue;
1332         }
1333         __regs_RtlRaiseException( &rec, context );
1334     }
1335 }
1336
1337 #else /* __HAVE_VM86 */
1338 /**********************************************************************
1339  *              __wine_enter_vm86   (NTDLL.@)
1340  */
1341 void __wine_enter_vm86( CONTEXT *context )
1342 {
1343     MESSAGE("vm86 mode not supported on this platform\n");
1344 }
1345 #endif /* __HAVE_VM86 */
1346
1347 /**********************************************************************
1348  *              DbgBreakPoint   (NTDLL.@)
1349  */
1350 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1351
1352 /**********************************************************************
1353  *              DbgUserBreakPoint   (NTDLL.@)
1354  */
1355 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1356
1357 #endif  /* __i386__ */