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