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 "winbase.h"
  56 #include "thread.h"
  57 #include "wine/library.h"
  58 #include "ntdll_misc.h"
  59
  60 /***********************************************************************
  61  * signal context platform-specific definitions
  62  */
  63
  64 #ifdef linux
  65 typedef struct
  66 {
  67     unsigned short sc_gs, __gsh;
  68     unsigned short sc_fs, __fsh;
  69     unsigned short sc_es, __esh;
  70     unsigned short sc_ds, __dsh;
  71     unsigned long sc_edi;
  72     unsigned long sc_esi;
  73     unsigned long sc_ebp;
  74     unsigned long sc_esp;
  75     unsigned long sc_ebx;
  76     unsigned long sc_edx;
  77     unsigned long sc_ecx;
  78     unsigned long sc_eax;
  79     unsigned long sc_trapno;
  80     unsigned long sc_err;
  81     unsigned long sc_eip;
  82     unsigned short sc_cs, __csh;
  83     unsigned long sc_eflags;
  84     unsigned long esp_at_signal;
  85     unsigned short sc_ss, __ssh;
  86     unsigned long i387;
  87     unsigned long oldmask;
  88     unsigned long cr2;
  89 } SIGCONTEXT;
  90
  91 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  92 #define HANDLER_CONTEXT (&__context)
  93
  94 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  95 struct kernel_sigaction
  96 {
  97     void (*ksa_handler)();
  98     unsigned long ksa_mask;
  99     unsigned long ksa_flags;
 100     void *ksa_restorer;
 101 };
 102
 103 /* Similar to the sigaction function in libc, except it leaves alone the
 104    restorer field, which is used to specify the signal stack address */
 105 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
 106                                   struct kernel_sigaction *old )
 107 {
 108     __asm__ __volatile__( "pushl %%ebx\n\t"
 109                           "movl %2,%%ebx\n\t"
 110                           "int $0x80\n\t"
 111                           "popl %%ebx"
 112                           : "=a" (sig)
 113                           : "0" (SYS_sigaction), "S" (sig), "c" (new), "d" (old) );
 114     if (sig>=0) return 0;
 115     errno = -sig;
 116     return -1;
 117 }
 118
 119 #ifdef HAVE_SIGALTSTACK
 120 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
 121 static inline int wine_sigaltstack( const struct sigaltstack *new,
 122                                     struct sigaltstack *old )
 123 {
 124     int ret;
 125     __asm__ __volatile__( "pushl %%ebx\n\t"
 126                           "movl %2,%%ebx\n\t"
 127                           "int $0x80\n\t"
 128                           "popl %%ebx"
 129                           : "=a" (ret)
 130                           : "0" (SYS_sigaltstack), "q" (new), "c" (old) );
 131     if (ret >= 0) return 0;
 132     errno = -ret;
 133     return -1;
 134 }
 135 #endif
 136
 137 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 138
 139 int vm86_enter( void **vm86_ptr );
 140 void vm86_return(void);
 141 void vm86_return_end(void);
 142 __ASM_GLOBAL_FUNC(vm86_enter,
 143                   "pushl %ebp\n\t"
 144                   "movl %esp, %ebp\n\t"
 145                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 146                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 147                   "movl (%ecx),%ecx\n\t"
 148                   "pushl %ebx\n\t"
 149                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 150                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 151                   "pushl %fs\n\t"
 152                   "pushl %gs\n\t"
 153                   "int $0x80\n"
 154                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 155                   __ASM_FUNC("vm86_return") "\n"
 156                   __ASM_NAME("vm86_return") ":\n\t"
 157                   "popl %gs\n\t"
 158                   "popl %fs\n\t"
 159                   "popl %ecx\n\t"
 160                   "popl %ebx\n\t"
 161                   "popl %ebp\n\t"
 162                   "testl %eax,%eax\n\t"
 163                   "jl 0f\n\t"
 164                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 165                   "je " __ASM_NAME("vm86_enter") "\n\t"
 166                   "0:\n\t"
 167                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 168                   "movl $0,(%ecx)\n\t"
 169                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 170                   __ASM_FUNC("vm86_return_end") "\n"
 171                   __ASM_NAME("vm86_return_end") ":\n\t"
 172                   "ret" );
 173
 174 #ifdef HAVE_SYS_VM86_H
 175 # define __HAVE_VM86
 176 #endif
 177
 178 #endif  /* linux */
 179
 180 #ifdef BSDI
 181
 182 #define EAX_sig(context)     ((context)->tf_eax)
 183 #define EBX_sig(context)     ((context)->tf_ebx)
 184 #define ECX_sig(context)     ((context)->tf_ecx)
 185 #define EDX_sig(context)     ((context)->tf_edx)
 186 #define ESI_sig(context)     ((context)->tf_esi)
 187 #define EDI_sig(context)     ((context)->tf_edi)
 188 #define EBP_sig(context)     ((context)->tf_ebp)
 189
 190 #define CS_sig(context)      ((context)->tf_cs)
 191 #define DS_sig(context)      ((context)->tf_ds)
 192 #define ES_sig(context)      ((context)->tf_es)
 193 #define SS_sig(context)      ((context)->tf_ss)
 194
 195 #include <machine/frame.h>
 196 typedef struct trapframe SIGCONTEXT;
 197
 198 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 199 #define HANDLER_CONTEXT __context
 200
 201 #define EFL_sig(context)     ((context)->tf_eflags)
 202
 203 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 204 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 205
 206 #endif /* bsdi */
 207
 208 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 209
 210 typedef struct sigcontext SIGCONTEXT;
 211
 212 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 213 #define HANDLER_CONTEXT __context
 214
 215 #endif  /* *BSD */
 216
 217 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 218
 219 #ifdef _SCO_DS
 220 #include <sys/regset.h>
 221 #endif
 222 /* Solaris kludge */
 223 #undef ERR
 224 #include <sys/ucontext.h>
 225 #undef ERR
 226 typedef struct ucontext SIGCONTEXT;
 227
 228 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 229 #define HANDLER_CONTEXT __context
 230
 231 #endif  /* svr4 || SCO_DS */
 232
 233 #ifdef __EMX__
 234
 235 typedef struct
 236 {
 237     unsigned long ContextFlags;
 238     FLOATING_SAVE_AREA sc_float;
 239     unsigned long sc_gs;
 240     unsigned long sc_fs;
 241     unsigned long sc_es;
 242     unsigned long sc_ds;
 243     unsigned long sc_edi;
 244     unsigned long sc_esi;
 245     unsigned long sc_eax;
 246     unsigned long sc_ebx;
 247     unsigned long sc_ecx;
 248     unsigned long sc_edx;
 249     unsigned long sc_ebp;
 250     unsigned long sc_eip;
 251     unsigned long sc_cs;
 252     unsigned long sc_eflags;
 253     unsigned long sc_esp;
 254     unsigned long sc_ss;
 255 } SIGCONTEXT;
 256
 257 #endif  /* __EMX__ */
 258
 259 #ifdef __CYGWIN__
 260
 261 /* FIXME: This section is just here so it can compile, it's most likely
 262  * completely wrong. */
 263
 264 typedef struct
 265 {
 266     unsigned short sc_gs, __gsh;
 267     unsigned short sc_fs, __fsh;
 268     unsigned short sc_es, __esh;
 269     unsigned short sc_ds, __dsh;
 270     unsigned long sc_edi;
 271     unsigned long sc_esi;
 272     unsigned long sc_ebp;
 273     unsigned long sc_esp;
 274     unsigned long sc_ebx;
 275     unsigned long sc_edx;
 276     unsigned long sc_ecx;
 277     unsigned long sc_eax;
 278     unsigned long sc_trapno;
 279     unsigned long sc_err;
 280     unsigned long sc_eip;
 281     unsigned short sc_cs, __csh;
 282     unsigned long sc_eflags;
 283     unsigned long esp_at_signal;
 284     unsigned short sc_ss, __ssh;
 285     unsigned long i387;
 286     unsigned long oldmask;
 287     unsigned long cr2;
 288 } SIGCONTEXT;
 289
 290 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
 291 #define HANDLER_CONTEXT (&__context)
 292
 293 #endif /* __CYGWIN__ */
 294
 295 #ifdef __APPLE__
 296 # include <sys/ucontext.h>
 297 # include <sys/types.h>
 298 # include <signal.h>
 299
 300 typedef siginfo_t siginfo;
 301 typedef struct ucontext SIGCONTEXT;
 302
 303 # define HANDLER_DEF(name) void name( int __signal, siginfo *__siginfo, SIGCONTEXT *__context )
 304 # define HANDLER_CONTEXT (__context)
 305
 306 #endif /* __APPLE__ */
 307
 308 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) ||\
 309     defined(__OpenBSD__) || defined(__EMX__) || defined(__CYGWIN__)
 310
 311 #define EAX_sig(context)     ((context)->sc_eax)
 312 #define EBX_sig(context)     ((context)->sc_ebx)
 313 #define ECX_sig(context)     ((context)->sc_ecx)
 314 #define EDX_sig(context)     ((context)->sc_edx)
 315 #define ESI_sig(context)     ((context)->sc_esi)
 316 #define EDI_sig(context)     ((context)->sc_edi)
 317 #define EBP_sig(context)     ((context)->sc_ebp)
 318
 319 #define CS_sig(context)      ((context)->sc_cs)
 320 #define DS_sig(context)      ((context)->sc_ds)
 321 #define ES_sig(context)      ((context)->sc_es)
 322 #define FS_sig(context)      ((context)->sc_fs)
 323 #define GS_sig(context)      ((context)->sc_gs)
 324 #define SS_sig(context)      ((context)->sc_ss)
 325
 326 #define TRAP_sig(context)    ((context)->sc_trapno)
 327
 328 #ifdef __NetBSD__
 329 #define ERROR_sig(context)   ((context)->sc_err)
 330 #endif
 331
 332 #ifdef linux
 333 #define ERROR_sig(context)   ((context)->sc_err)
 334 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 335 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->cr2)
 336 #endif
 337
 338 #ifdef __FreeBSD__
 339 #define EFL_sig(context)     ((context)->sc_efl)
 340 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 341 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->sc_err)
 342 #else
 343 #define EFL_sig(context)     ((context)->sc_eflags)
 344 #endif
 345
 346 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 347 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 348
 349 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 350
 351 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 352
 353 #ifdef _SCO_DS
 354 #define gregs regs
 355 #endif
 356
 357 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 358 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 359 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 360 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 361 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 362 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 363 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 364
 365 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 366 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 367 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 368 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 369
 370 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 371 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 372
 373 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 374
 375 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 376 #ifdef UESP
 377 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 378 #elif defined(R_ESP)
 379 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 380 #else
 381 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 382 #endif
 383 #ifdef TRAPNO
 384 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 385 #endif
 386
 387 #define FAULT_ADDRESS         (__siginfo->si_addr)
 388
 389 #endif  /* svr4 || SCO_DS */
 390
 391 #ifdef __APPLE__
 392 #define EAX_sig(context)     ((context)->uc_mcontext.sc_eax)
 393 #define EBX_sig(context)     ((context)->uc_mcontext.sc_ebx)
 394 #define ECX_sig(context)     ((context)->uc_mcontext.sc_ecx)
 395 #define EDX_sig(context)     ((context)->uc_mcontext.sc_edx)
 396 #define ESI_sig(context)     ((context)->uc_mcontext.sc_esi)
 397 #define EDI_sig(context)     ((context)->uc_mcontext.sc_edi)
 398 #define EBP_sig(context)     ((context)->uc_mcontext.sc_ebp)
 399
 400 #define CS_sig(context)      ((context)->uc_mcontext.sc_cs)
 401 #define DS_sig(context)      ((context)->uc_mcontext.sc_ds)
 402 #define ES_sig(context)      ((context)->uc_mcontext.sc_es)
 403 #define FS_sig(context)      ((context)->uc_mcontext.sc_fs)
 404 #define GS_sig(context)      ((context)->uc_mcontext.sc_gs)
 405 #define SS_sig(context)      ((context)->uc_mcontext.sc_ss)
 406
 407 #define EFL_sig(context)     ((context)->uc_mcontext.sc_eflags)
 408
 409 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext.sc_eip))
 410 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext.sc_esp))
 411
 412 #endif /* __APPLE__ */
 413
 414 /* exception code definitions (already defined by FreeBSD/NetBSD) */
 415 #if !defined(__FreeBSD__) && !defined(__NetBSD__) /* FIXME: other BSDs? */
 416 #define T_DIVIDE        0   /* Division by zero exception */
 417 #define T_TRCTRAP       1   /* Single-step exception */
 418 #define T_NMI           2   /* NMI interrupt */
 419 #define T_BPTFLT        3   /* Breakpoint exception */
 420 #define T_OFLOW         4   /* Overflow exception */
 421 #define T_BOUND         5   /* Bound range exception */
 422 #define T_PRIVINFLT     6   /* Invalid opcode exception */
 423 #define T_DNA           7   /* Device not available exception */
 424 #define T_DOUBLEFLT     8   /* Double fault exception */
 425 #define T_FPOPFLT       9   /* Coprocessor segment overrun */
 426 #define T_TSSFLT        10  /* Invalid TSS exception */
 427 #define T_SEGNPFLT      11  /* Segment not present exception */
 428 #define T_STKFLT        12  /* Stack fault */
 429 #define T_PROTFLT       13  /* General protection fault */
 430 #define T_PAGEFLT       14  /* Page fault */
 431 #define T_RESERVED      15  /* Unknown exception */
 432 #define T_ARITHTRAP     16  /* Floating point exception */
 433 #define T_ALIGNFLT      17  /* Alignment check exception */
 434 #define T_MCHK          18  /* Machine check exception */
 435 #define T_CACHEFLT      19  /* Cache flush exception */
 436 #endif
 437 #if defined(__NetBSD__)
 438 #define T_MCHK          19  /* Machine check exception */
 439 #endif
 440
 441 #define T_UNKNOWN     (-1)  /* Unknown fault (TRAP_sig not defined) */
 442
 443 #include "wine/exception.h"
 444 #include "wine/debug.h"
 445
 446 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 447
 448 typedef int (*wine_signal_handler)(unsigned int sig);
 449
 450 static wine_signal_handler handlers[256];
 451
 452 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( CONTEXT context );
 453
 454
 455 /***********************************************************************
 456  *           dispatch_signal
 457  */
 458 inline static int dispatch_signal(unsigned int sig)
 459 {
 460     if (handlers[sig] == NULL) return 0;
 461     return handlers[sig](sig);
 462 }
 463
 464
 465 /***********************************************************************
 466  *           get_trap_code
 467  *
 468  * Get the trap code for a signal.
 469  */
 470 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 471 {
 472 #ifdef TRAP_sig
 473     return TRAP_sig(sigcontext);
 474 #else
 475     return T_UNKNOWN;  /* unknown trap code */
 476 #endif
 477 }
 478
 479 /***********************************************************************
 480  *           get_error_code
 481  *
 482  * Get the error code for a signal.
 483  */
 484 static inline int get_error_code( const SIGCONTEXT *sigcontext )
 485 {
 486 #ifdef ERROR_sig
 487     return ERROR_sig(sigcontext);
 488 #else
 489     return 0;
 490 #endif
 491 }
 492
 493 /***********************************************************************
 494  *           get_signal_stack
 495  *
 496  * Get the base of the signal stack for the current thread.
 497  */
 498 static inline void *get_signal_stack(void)
 499 {
 500     return (char *)NtCurrentTeb() + 4096;
 501 }
 502
 503
 504 /***********************************************************************
 505  *           get_current_teb
 506  *
 507  * Get the current teb based on the stack pointer.
 508  */
 509 static inline TEB *get_current_teb(void)
 510 {
 511     unsigned long esp;
 512     __asm__("movl %%esp,%0" : "=g" (esp) );
 513     return (TEB *)((esp & ~4095) - 4096);
 514 }
 515
 516
 517 #ifdef __HAVE_VM86
 518 /***********************************************************************
 519  *           save_vm86_context
 520  *
 521  * Set the register values from a vm86 structure.
 522  */
 523 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 524 {
 525     context->Eax    = vm86->regs.eax;
 526     context->Ebx    = vm86->regs.ebx;
 527     context->Ecx    = vm86->regs.ecx;
 528     context->Edx    = vm86->regs.edx;
 529     context->Esi    = vm86->regs.esi;
 530     context->Edi    = vm86->regs.edi;
 531     context->Esp    = vm86->regs.esp;
 532     context->Ebp    = vm86->regs.ebp;
 533     context->Eip    = vm86->regs.eip;
 534     context->SegCs  = vm86->regs.cs;
 535     context->SegDs  = vm86->regs.ds;
 536     context->SegEs  = vm86->regs.es;
 537     context->SegFs  = vm86->regs.fs;
 538     context->SegGs  = vm86->regs.gs;
 539     context->SegSs  = vm86->regs.ss;
 540     context->EFlags = vm86->regs.eflags;
 541 }
 542
 543
 544 /***********************************************************************
 545  *           restore_vm86_context
 546  *
 547  * Build a vm86 structure from the register values.
 548  */
 549 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 550 {
 551     vm86->regs.eax    = context->Eax;
 552     vm86->regs.ebx    = context->Ebx;
 553     vm86->regs.ecx    = context->Ecx;
 554     vm86->regs.edx    = context->Edx;
 555     vm86->regs.esi    = context->Esi;
 556     vm86->regs.edi    = context->Edi;
 557     vm86->regs.esp    = context->Esp;
 558     vm86->regs.ebp    = context->Ebp;
 559     vm86->regs.eip    = context->Eip;
 560     vm86->regs.cs     = context->SegCs;
 561     vm86->regs.ds     = context->SegDs;
 562     vm86->regs.es     = context->SegEs;
 563     vm86->regs.fs     = context->SegFs;
 564     vm86->regs.gs     = context->SegGs;
 565     vm86->regs.ss     = context->SegSs;
 566     vm86->regs.eflags = context->EFlags;
 567 }
 568
 569
 570 /**********************************************************************
 571  *              merge_vm86_pending_flags
 572  *
 573  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 574  * raises exception if there are pending events and VIF flag
 575  * has been turned on.
 576  *
 577  * Called from __wine_enter_vm86 because vm86_enter
 578  * doesn't check for pending events.
 579  *
 580  * Called from raise_vm86_sti_exception to check for
 581  * pending events in a signal safe way.
 582  */
 583 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 584 {
 585     BOOL check_pending = TRUE;
 586     struct vm86plus_struct *vm86 =
 587         (struct vm86plus_struct*)(NtCurrentTeb()->vm86_ptr);
 588
 589     /*
 590      * In order to prevent a race when SIGUSR2 occurs while
 591      * we are returning from exception handler, pending events
 592      * will be rechecked after each raised exception.
 593      */
 594     while (check_pending && NtCurrentTeb()->vm86_pending)
 595     {
 596         check_pending = FALSE;
 597         NtCurrentTeb()->vm86_ptr = NULL;
 598
 599         /*
 600          * If VIF is set, throw exception.
 601          * Note that SIGUSR2 may turn VIF flag off so
 602          * VIF check must occur only when TEB.vm86_ptr is NULL.
 603          */
 604         if (vm86->regs.eflags & VIF_MASK)
 605         {
 606             CONTEXT vcontext;
 607             save_vm86_context( &vcontext, vm86 );
 608
 609             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 610             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 611             rec->ExceptionRecord  = NULL;
 612             rec->NumberParameters = 0;
 613             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 614
 615             vcontext.EFlags &= ~VIP_MASK;
 616             NtCurrentTeb()->vm86_pending = 0;
 617             __regs_RtlRaiseException( rec, &vcontext );
 618
 619             restore_vm86_context( &vcontext, vm86 );
 620             check_pending = TRUE;
 621         }
 622
 623         NtCurrentTeb()->vm86_ptr = vm86;
 624     }
 625
 626     /*
 627      * Merge VIP flags in a signal safe way. This requires
 628      * that the following operation compiles into atomic
 629      * instruction.
 630      */
 631     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 632 }
 633 #endif /* __HAVE_VM86 */
 634
 635
 636 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 637
 638
 639 /***********************************************************************
 640  *           init_handler
 641  *
 642  * Handler initialization when the full context is not needed.
 643  */
 644 static void *init_handler( const SIGCONTEXT *sigcontext )
 645 {
 646     void *stack = (void *)ESP_sig(sigcontext);
 647     TEB *teb = get_current_teb();
 648
 649     wine_set_fs( teb->teb_sel );
 650
 651     /* now restore a proper %gs for the fault handler */
 652     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 653         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 654     {
 655         /*
 656          * Win16 or DOS protected mode. Note that during switch
 657          * from 16-bit mode to linear mode, CS may be set to system
 658          * segment before FS is restored. Fortunately, in this case
 659          * SS is still non-system segment. This is why both CS and SS
 660          * are checked.
 661          */
 662         wine_set_gs( teb->gs_sel );
 663         stack = teb->WOW32Reserved;
 664     }
 665 #ifdef __HAVE_VM86
 666     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 667     {
 668         unsigned int *int_stack = stack;
 669         /* fetch the saved %gs from the stack */
 670         wine_set_gs( int_stack[0] );
 671     }
 672 #endif
 673     else  /* 32-bit mode */
 674     {
 675 #ifdef GS_sig
 676         wine_set_gs( GS_sig(sigcontext) );
 677 #endif
 678     }
 679     return stack;
 680 }
 681
 682
 683 /***********************************************************************
 684  *           save_fpu
 685  *
 686  * Set the FPU context from a sigcontext.
 687  */
 688 inline static void save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 689 {
 690 #ifdef FPU_sig
 691     if (FPU_sig(sigcontext))
 692     {
 693         context->FloatSave = *FPU_sig(sigcontext);
 694         return;
 695     }
 696 #endif  /* FPU_sig */
 697 #ifdef __GNUC__
 698     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 699 #endif  /* __GNUC__ */
 700 }
 701
 702
 703 /***********************************************************************
 704  *           restore_fpu
 705  *
 706  * Restore the FPU context to a sigcontext.
 707  */
 708 inline static void restore_fpu( CONTEXT *context )
 709 {
 710     /* reset the current interrupt status */
 711     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 712 #ifdef __GNUC__
 713     /* avoid nested exceptions */
 714     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 715 #endif  /* __GNUC__ */
 716 }
 717
 718
 719 /***********************************************************************
 720  *           setup_exception
 721  *
 722  * Setup a proper stack frame for the raise function, and modify the
 723  * sigcontext so that the return from the signal handler will call
 724  * the raise function.
 725  */
 726 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 727 {
 728     struct stack_layout
 729     {
 730         void             *ret_addr;      /* return address from raise_func */
 731         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 732         CONTEXT          *context_ptr;   /* second arg for raise_func */
 733         void             *dummy;         /* dummy ret addr for __wine_call_from_32_restore_regs */
 734         CONTEXT           context;
 735         EXCEPTION_RECORD  rec;
 736         DWORD             ebp;
 737         DWORD             eip;
 738     } *stack;
 739
 740     WORD fs, gs;
 741
 742     /* get %fs and %gs at time of the fault */
 743 #ifdef FS_sig
 744     fs = LOWORD(FS_sig(sigcontext));
 745 #else
 746     fs = wine_get_fs();
 747 #endif
 748 #ifdef GS_sig
 749     gs = LOWORD(GS_sig(sigcontext));
 750 #else
 751     gs = wine_get_gs();
 752 #endif
 753
 754     stack = init_handler( sigcontext );
 755
 756     /* stack sanity checks */
 757
 758     if ((char *)stack >= (char *)get_signal_stack() &&
 759         (char *)stack < (char *)get_signal_stack() + SIGNAL_STACK_SIZE)
 760     {
 761         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 762              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 763              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 764         server_abort_thread(1);
 765     }
 766
 767     if ((char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit + 4096 ||
 768         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 769     {
 770         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit + 4096 - (char *)stack;
 771         if (diff < 4096)
 772         {
 773             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 774                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 775                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 776             server_abort_thread(1);
 777         }
 778         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 779                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 780                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 781     }
 782
 783     stack--;  /* push the stack_layout structure */
 784     stack->ret_addr     = __wine_call_from_32_restore_regs;
 785     stack->rec_ptr      = &stack->rec;
 786     stack->context_ptr  = &stack->context;
 787
 788     stack->rec.ExceptionRecord  = NULL;
 789     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 790     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 791     stack->rec.NumberParameters = 0;
 792
 793     stack->context.ContextFlags = CONTEXT_FULL;
 794     stack->context.Eax          = EAX_sig(sigcontext);
 795     stack->context.Ebx          = EBX_sig(sigcontext);
 796     stack->context.Ecx          = ECX_sig(sigcontext);
 797     stack->context.Edx          = EDX_sig(sigcontext);
 798     stack->context.Esi          = ESI_sig(sigcontext);
 799     stack->context.Edi          = EDI_sig(sigcontext);
 800     stack->context.Ebp          = EBP_sig(sigcontext);
 801     stack->context.EFlags       = EFL_sig(sigcontext);
 802     stack->context.Eip          = EIP_sig(sigcontext);
 803     stack->context.Esp          = ESP_sig(sigcontext);
 804     stack->context.SegCs        = LOWORD(CS_sig(sigcontext));
 805     stack->context.SegDs        = LOWORD(DS_sig(sigcontext));
 806     stack->context.SegEs        = LOWORD(ES_sig(sigcontext));
 807     stack->context.SegFs        = fs;
 808     stack->context.SegGs        = gs;
 809     stack->context.SegSs        = LOWORD(SS_sig(sigcontext));
 810
 811     /* now modify the sigcontext to return to the raise function */
 812     ESP_sig(sigcontext) = (DWORD)stack;
 813     EIP_sig(sigcontext) = (DWORD)func;
 814     CS_sig(sigcontext)  = wine_get_cs();
 815     DS_sig(sigcontext)  = wine_get_ds();
 816     ES_sig(sigcontext)  = wine_get_es();
 817     FS_sig(sigcontext)  = wine_get_fs();
 818     GS_sig(sigcontext)  = wine_get_gs();
 819     SS_sig(sigcontext)  = wine_get_ss();
 820
 821     return stack->rec_ptr;
 822 }
 823
 824
 825 /***********************************************************************
 826  *           get_exception_context
 827  *
 828  * Get a pointer to the context built by setup_exception.
 829  */
 830 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 831 {
 832     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 833 }
 834
 835
 836 /**********************************************************************
 837  *              get_fpu_code
 838  *
 839  * Get the FPU exception code from the FPU status.
 840  */
 841 static inline DWORD get_fpu_code( const CONTEXT *context )
 842 {
 843     DWORD status = context->FloatSave.StatusWord;
 844
 845     if (status & 0x01)  /* IE */
 846     {
 847         if (status & 0x40)  /* SF */
 848             return EXCEPTION_FLT_STACK_CHECK;
 849         else
 850             return EXCEPTION_FLT_INVALID_OPERATION;
 851     }
 852     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 853     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 854     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 855     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 856     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 857     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 858 }
 859
 860
 861 /**********************************************************************
 862  *              raise_segv_exception
 863  */
 864 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 865 {
 866     switch(rec->ExceptionCode)
 867     {
 868     case EXCEPTION_ACCESS_VIOLATION:
 869         if (rec->NumberParameters == 2)
 870         {
 871             if (!(rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] )))
 872                 return;
 873         }
 874         break;
 875     case EXCEPTION_DATATYPE_MISALIGNMENT:
 876         /* FIXME: pass through exception handler first? */
 877         if (context->EFlags & 0x00040000)
 878         {
 879             /* Disable AC flag, return */
 880             context->EFlags &= ~0x00040000;
 881             return;
 882         }
 883         break;
 884     }
 885     __regs_RtlRaiseException( rec, context );
 886 }
 887
 888
 889 /**********************************************************************
 890  *              raise_trap_exception
 891  */
 892 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 893 {
 894     DWORD dr0, dr1, dr2, dr3, dr6, dr7;
 895
 896     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
 897     {
 898         if (context->EFlags & 0x100)
 899         {
 900             context->EFlags &= ~0x100;  /* clear single-step flag */
 901         }
 902         else  /* hardware breakpoint, fetch the debug registers */
 903         {
 904             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
 905             NtGetContextThread(GetCurrentThread(), context);
 906             /* do we really have a bp from a debug register ?
 907              * if not, then someone did a kill(SIGTRAP) on us, and we
 908              * shall return a breakpoint, not a single step exception
 909              */
 910             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
 911         }
 912     }
 913
 914     dr0 = context->Dr0;
 915     dr1 = context->Dr1;
 916     dr2 = context->Dr2;
 917     dr3 = context->Dr3;
 918     dr6 = context->Dr6;
 919     dr7 = context->Dr7;
 920
 921     __regs_RtlRaiseException( rec, context );
 922
 923     if (dr0 != context->Dr0 || dr1 != context->Dr1 || dr2 != context->Dr2 ||
 924         dr3 != context->Dr3 || dr6 != context->Dr6 || dr7 != context->Dr7)
 925     {
 926         /* the debug registers have changed, set the new values */
 927         context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
 928         NtSetContextThread(GetCurrentThread(), context);
 929     }
 930 }
 931
 932
 933 /**********************************************************************
 934  *              raise_fpu_exception
 935  */
 936 static void WINAPI raise_fpu_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 937 {
 938     __regs_RtlRaiseException( rec, context );
 939     restore_fpu( context );
 940 }
 941
 942
 943 #ifdef __HAVE_VM86
 944 /**********************************************************************
 945  *              raise_vm86_sti_exception
 946  */
 947 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 948 {
 949     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
 950     NtCurrentTeb()->vm86_pending |= VIP_MASK;
 951
 952     if (NtCurrentTeb()->vm86_ptr)
 953     {
 954         if (((char*)context->Eip >= (char*)vm86_return) &&
 955             ((char*)context->Eip <= (char*)vm86_return_end) &&
 956             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
 957             /* exiting from VM86, can't throw */
 958             return;
 959         }
 960         merge_vm86_pending_flags( rec );
 961     }
 962     else if (NtCurrentTeb()->dpmi_vif &&
 963              !wine_ldt_is_system(context->SegCs) &&
 964              !wine_ldt_is_system(context->SegSs))
 965     {
 966         /* Executing DPMI code and virtual interrupts are enabled. */
 967         NtCurrentTeb()->vm86_pending = 0;
 968         __regs_RtlRaiseException( rec, context );
 969     }
 970 }
 971
 972
 973 /**********************************************************************
 974  *              usr2_handler
 975  *
 976  * Handler for SIGUSR2.
 977  * We use it to signal that the running __wine_enter_vm86() should
 978  * immediately set VIP_MASK, causing pending events to be handled
 979  * as early as possible.
 980  */
 981 static HANDLER_DEF(usr2_handler)
 982 {
 983     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
 984     rec->ExceptionCode = EXCEPTION_VM86_STI;
 985 }
 986 #endif /* __HAVE_VM86 */
 987
 988
 989 /**********************************************************************
 990  *              segv_handler
 991  *
 992  * Handler for SIGSEGV and related errors.
 993  */
 994 static HANDLER_DEF(segv_handler)
 995 {
 996     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
 997
 998     switch(get_trap_code(HANDLER_CONTEXT))
 999     {
1000     case T_OFLOW:   /* Overflow exception */
1001         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1002         break;
1003     case T_BOUND:   /* Bound range exception */
1004         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1005         break;
1006     case T_PRIVINFLT:   /* Invalid opcode exception */
1007         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1008         break;
1009     case T_STKFLT:  /* Stack fault */
1010         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1011         break;
1012     case T_SEGNPFLT:  /* Segment not present exception */
1013     case T_PROTFLT:   /* General protection fault */
1014     case T_UNKNOWN:   /* Unknown fault code */
1015         rec->ExceptionCode = get_error_code(HANDLER_CONTEXT) ? EXCEPTION_ACCESS_VIOLATION
1016                                                              : EXCEPTION_PRIV_INSTRUCTION;
1017         break;
1018     case T_PAGEFLT:  /* Page fault */
1019         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1020 #ifdef FAULT_ADDRESS
1021         rec->NumberParameters = 2;
1022         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) & 2) != 0;
1023         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1024 #endif
1025         break;
1026     case T_ALIGNFLT:  /* Alignment check exception */
1027         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1028         break;
1029     default:
1030         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1031         /* fall through */
1032     case T_NMI:       /* NMI interrupt */
1033     case T_DNA:       /* Device not available exception */
1034     case T_DOUBLEFLT: /* Double fault exception */
1035     case T_TSSFLT:    /* Invalid TSS exception */
1036     case T_RESERVED:  /* Unknown exception */
1037     case T_MCHK:      /* Machine check exception */
1038 #ifdef T_CACHEFLT
1039     case T_CACHEFLT:  /* Cache flush exception */
1040 #endif
1041         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1042         break;
1043     }
1044 }
1045
1046
1047 /**********************************************************************
1048  *              trap_handler
1049  *
1050  * Handler for SIGTRAP.
1051  */
1052 static HANDLER_DEF(trap_handler)
1053 {
1054     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1055
1056     switch(get_trap_code(HANDLER_CONTEXT))
1057     {
1058     case T_TRCTRAP:  /* Single-step exception */
1059         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1060         EFL_sig(HANDLER_CONTEXT) &= ~0x100;  /* clear single-step flag */
1061         break;
1062     case T_BPTFLT:   /* Breakpoint exception */
1063         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1064         /* fall through */
1065     default:
1066         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1067         break;
1068     }
1069 }
1070
1071
1072 /**********************************************************************
1073  *              fpe_handler
1074  *
1075  * Handler for SIGFPE.
1076  */
1077 static HANDLER_DEF(fpe_handler)
1078 {
1079     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_fpu_exception );
1080     CONTEXT *context;
1081
1082     context = get_exception_context( rec );
1083     save_fpu( context, HANDLER_CONTEXT );
1084
1085     switch(get_trap_code(HANDLER_CONTEXT))
1086     {
1087     case T_DIVIDE:   /* Division by zero exception */
1088         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1089         break;
1090     case T_FPOPFLT:   /* Coprocessor segment overrun */
1091         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1092         break;
1093     case T_ARITHTRAP:  /* Floating point exception */
1094     case T_UNKNOWN:    /* Unknown fault code */
1095         rec->ExceptionCode = get_fpu_code( context );
1096         break;
1097     default:
1098         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1099         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1100         break;
1101     }
1102 }
1103
1104
1105 /**********************************************************************
1106  *              int_handler
1107  *
1108  * Handler for SIGINT.
1109  */
1110 static HANDLER_DEF(int_handler)
1111 {
1112     init_handler( HANDLER_CONTEXT );
1113     if (!dispatch_signal(SIGINT))
1114     {
1115         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1116         rec->ExceptionCode = CONTROL_C_EXIT;
1117     }
1118 }
1119
1120 /**********************************************************************
1121  *              abrt_handler
1122  *
1123  * Handler for SIGABRT.
1124  */
1125 static HANDLER_DEF(abrt_handler)
1126 {
1127     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1128     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1129     rec->ExceptionFlags = EH_NONCONTINUABLE;
1130 }
1131
1132
1133 /**********************************************************************
1134  *              term_handler
1135  *
1136  * Handler for SIGTERM.
1137  */
1138 static HANDLER_DEF(term_handler)
1139 {
1140     init_handler( HANDLER_CONTEXT );
1141     server_abort_thread(0);
1142 }
1143
1144
1145 /**********************************************************************
1146  *              usr1_handler
1147  *
1148  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1149  */
1150 static HANDLER_DEF(usr1_handler)
1151 {
1152     LARGE_INTEGER timeout;
1153
1154     init_handler( HANDLER_CONTEXT );
1155     /* wait with 0 timeout, will only return once the thread is no longer suspended */
1156     timeout.QuadPart = 0;
1157     NTDLL_wait_for_multiple_objects( 0, NULL, 0, &timeout, 0 );
1158 }
1159
1160
1161 /***********************************************************************
1162  *           set_handler
1163  *
1164  * Set a signal handler
1165  */
1166 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1167 {
1168     struct sigaction sig_act;
1169
1170 #ifdef linux
1171     if (!have_sigaltstack)
1172     {
1173         struct kernel_sigaction sig_act;
1174         sig_act.ksa_handler = func;
1175         sig_act.ksa_flags   = SA_RESTART;
1176         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1177                               (1 << (SIGUSR2-1));
1178         /* point to the top of the signal stack */
1179         sig_act.ksa_restorer = (char *)get_signal_stack() + SIGNAL_STACK_SIZE;
1180         return wine_sigaction( sig, &sig_act, NULL );
1181     }
1182 #endif  /* linux */
1183     sig_act.sa_handler = func;
1184     sigemptyset( &sig_act.sa_mask );
1185     sigaddset( &sig_act.sa_mask, SIGINT );
1186     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1187
1188 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
1189     sig_act.sa_flags = SA_RESTART;
1190 #elif defined (__svr4__) || defined(_SCO_DS)
1191     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1192 #else
1193     sig_act.sa_flags = 0;
1194 #endif
1195
1196 #ifdef SA_ONSTACK
1197     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1198 #endif
1199     return sigaction( sig, &sig_act, NULL );
1200 }
1201
1202
1203 /***********************************************************************
1204  *           __wine_set_signal_handler   (NTDLL.@)
1205  */
1206 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1207 {
1208     if (sig > sizeof(handlers) / sizeof(handlers[0])) return -1;
1209     if (handlers[sig] != NULL) return -2;
1210     handlers[sig] = wsh;
1211     return 0;
1212 }
1213
1214
1215 /**********************************************************************
1216  *              SIGNAL_Init
1217  */
1218 BOOL SIGNAL_Init(void)
1219 {
1220     int have_sigaltstack = 0;
1221
1222 #ifdef HAVE_SIGALTSTACK
1223     struct sigaltstack ss;
1224     ss.ss_sp    = get_signal_stack();
1225     ss.ss_size  = SIGNAL_STACK_SIZE;
1226     ss.ss_flags = 0;
1227     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1228 #ifdef linux
1229     /* sigaltstack may fail because the kernel is too old, or
1230        because glibc is brain-dead. In the latter case a
1231        direct system call should succeed. */
1232     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1233 #endif  /* linux */
1234 #endif  /* HAVE_SIGALTSTACK */
1235
1236     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1237     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1238     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1239     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1240     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1241     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1242     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1243 #ifdef SIGBUS
1244     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1245 #endif
1246 #ifdef SIGTRAP
1247     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1248 #endif
1249
1250 #ifdef __HAVE_VM86
1251     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1252 #endif
1253
1254     return TRUE;
1255
1256  error:
1257     perror("sigaction");
1258     return FALSE;
1259 }
1260
1261
1262 #ifdef __HAVE_VM86
1263 /**********************************************************************
1264  *              __wine_enter_vm86   (NTDLL.@)
1265  *
1266  * Enter vm86 mode with the specified register context.
1267  */
1268 void __wine_enter_vm86( CONTEXT *context )
1269 {
1270     EXCEPTION_RECORD rec;
1271     TEB *teb = NtCurrentTeb();
1272     int res;
1273     struct vm86plus_struct vm86;
1274
1275     memset( &vm86, 0, sizeof(vm86) );
1276     for (;;)
1277     {
1278         restore_vm86_context( context, &vm86 );
1279
1280         teb->vm86_ptr = &vm86;
1281         merge_vm86_pending_flags( &rec );
1282
1283         res = vm86_enter( &teb->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1284         if (res < 0)
1285         {
1286             errno = -res;
1287             return;
1288         }
1289
1290         save_vm86_context( context, &vm86 );
1291
1292         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1293         rec.ExceptionRecord  = NULL;
1294         rec.ExceptionAddress = (LPVOID)context->Eip;
1295         rec.NumberParameters = 0;
1296
1297         switch(VM86_TYPE(res))
1298         {
1299         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1300             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1301             raise_segv_exception( &rec, context );
1302             continue;
1303         case VM86_TRAP: /* return due to DOS-debugger request */
1304             switch(VM86_ARG(res))
1305             {
1306             case T_TRCTRAP:  /* Single-step exception, single step flag is cleared by raise_trap_exception */
1307                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1308                 break;
1309             case T_BPTFLT:   /* Breakpoint exception */
1310                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1311                 /* fall through */
1312             default:
1313                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1314                 break;
1315             }
1316             raise_trap_exception( &rec, context );
1317             continue;
1318         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1319             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1320             rec.NumberParameters = 1;
1321             rec.ExceptionInformation[0] = VM86_ARG(res);
1322             break;
1323         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1324             context->EFlags |= VIF_MASK;
1325             context->EFlags &= ~VIP_MASK;
1326             teb->vm86_pending = 0;
1327             rec.ExceptionCode = EXCEPTION_VM86_STI;
1328             break;
1329         case VM86_PICRETURN: /* return due to pending PIC request */
1330             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1331             break;
1332         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1333         default:
1334             ERR( "unhandled result from vm86 mode %x\n", res );
1335             continue;
1336         }
1337         __regs_RtlRaiseException( &rec, context );
1338     }
1339 }
1340
1341 #else /* __HAVE_VM86 */
1342 /**********************************************************************
1343  *              __wine_enter_vm86   (NTDLL.@)
1344  */
1345 void __wine_enter_vm86( CONTEXT *context )
1346 {
1347     MESSAGE("vm86 mode not supported on this platform\n");
1348 }
1349 #endif /* __HAVE_VM86 */
1350
1351 /**********************************************************************
1352  *              DbgBreakPoint   (NTDLL.@)
1353  */
1354 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1355
1356 /**********************************************************************
1357  *              DbgUserBreakPoint   (NTDLL.@)
1358  */
1359 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1360
1361 #endif  /* __i386__ */