dlls/ntdll/signal_i386.c

   1 /*
   2  * i386 signal handling routines
   3  *
   4  * Copyright 1999 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #ifdef __i386__
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdlib.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #ifdef HAVE_UNISTD_H
  32 # include <unistd.h>
  33 #endif
  34
  35 #ifdef HAVE_SYS_PARAM_H
  36 # include <sys/param.h>
  37 #endif
  38 #ifdef HAVE_SYSCALL_H
  39 # include <syscall.h>
  40 #else
  41 # ifdef HAVE_SYS_SYSCALL_H
  42 #  include <sys/syscall.h>
  43 # endif
  44 #endif
  45
  46 #ifdef HAVE_SYS_VM86_H
  47 # include <sys/vm86.h>
  48 #endif
  49
  50 #ifdef HAVE_SYS_SIGNAL_H
  51 # include <sys/signal.h>
  52 #endif
  53
  54 #include "windef.h"
  55 #include "thread.h"
  56 #include "wine/library.h"
  57 #include "ntdll_misc.h"
  58
  59 /***********************************************************************
  60  * signal context platform-specific definitions
  61  */
  62
  63 #ifdef linux
  64 typedef struct
  65 {
  66     unsigned short sc_gs, __gsh;
  67     unsigned short sc_fs, __fsh;
  68     unsigned short sc_es, __esh;
  69     unsigned short sc_ds, __dsh;
  70     unsigned long sc_edi;
  71     unsigned long sc_esi;
  72     unsigned long sc_ebp;
  73     unsigned long sc_esp;
  74     unsigned long sc_ebx;
  75     unsigned long sc_edx;
  76     unsigned long sc_ecx;
  77     unsigned long sc_eax;
  78     unsigned long sc_trapno;
  79     unsigned long sc_err;
  80     unsigned long sc_eip;
  81     unsigned short sc_cs, __csh;
  82     unsigned long sc_eflags;
  83     unsigned long esp_at_signal;
  84     unsigned short sc_ss, __ssh;
  85     unsigned long i387;
  86     unsigned long oldmask;
  87     unsigned long cr2;
  88 } volatile SIGCONTEXT;
  89
  90 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  91 #define HANDLER_CONTEXT (&__context)
  92
  93 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  94 struct kernel_sigaction
  95 {
  96     void (*ksa_handler)();
  97     unsigned long ksa_mask;
  98     unsigned long ksa_flags;
  99     void *ksa_restorer;
 100 };
 101
 102 /* Similar to the sigaction function in libc, except it leaves alone the
 103    restorer field, which is used to specify the signal stack address */
 104 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
 105                                   struct kernel_sigaction *old )
 106 {
 107     __asm__ __volatile__( "pushl %%ebx\n\t"
 108                           "movl %2,%%ebx\n\t"
 109                           "int $0x80\n\t"
 110                           "popl %%ebx"
 111                           : "=a" (sig)
 112                           : "0" (SYS_sigaction), "S" (sig), "c" (new), "d" (old) );
 113     if (sig>=0) return 0;
 114     errno = -sig;
 115     return -1;
 116 }
 117
 118 #ifdef HAVE_SIGALTSTACK
 119 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
 120 static inline int wine_sigaltstack( const struct sigaltstack *new,
 121                                     struct sigaltstack *old )
 122 {
 123     int ret;
 124     __asm__ __volatile__( "pushl %%ebx\n\t"
 125                           "movl %2,%%ebx\n\t"
 126                           "int $0x80\n\t"
 127                           "popl %%ebx"
 128                           : "=a" (ret)
 129                           : "0" (SYS_sigaltstack), "q" (new), "c" (old) );
 130     if (ret >= 0) return 0;
 131     errno = -ret;
 132     return -1;
 133 }
 134 #endif
 135
 136 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 137
 138 int vm86_enter( void **vm86_ptr );
 139 void vm86_return(void);
 140 void vm86_return_end(void);
 141 __ASM_GLOBAL_FUNC(vm86_enter,
 142                   "pushl %ebp\n\t"
 143                   "movl %esp, %ebp\n\t"
 144                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 145                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 146                   "movl (%ecx),%ecx\n\t"
 147                   "pushl %ebx\n\t"
 148                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 149                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 150                   "pushl %fs\n\t"
 151                   "pushl %gs\n\t"
 152                   "int $0x80\n"
 153                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 154                   __ASM_FUNC("vm86_return") "\n"
 155                   __ASM_NAME("vm86_return") ":\n\t"
 156                   "popl %gs\n\t"
 157                   "popl %fs\n\t"
 158                   "popl %ecx\n\t"
 159                   "popl %ebx\n\t"
 160                   "popl %ebp\n\t"
 161                   "testl %eax,%eax\n\t"
 162                   "jl 0f\n\t"
 163                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 164                   "je " __ASM_NAME("vm86_enter") "\n\t"
 165                   "0:\n\t"
 166                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 167                   "movl $0,(%ecx)\n\t"
 168                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 169                   __ASM_FUNC("vm86_return_end") "\n"
 170                   __ASM_NAME("vm86_return_end") ":\n\t"
 171                   "ret" );
 172
 173 #ifdef HAVE_SYS_VM86_H
 174 # define __HAVE_VM86
 175 #endif
 176
 177 #endif  /* linux */
 178
 179 #ifdef BSDI
 180
 181 #define EAX_sig(context)     ((context)->tf_eax)
 182 #define EBX_sig(context)     ((context)->tf_ebx)
 183 #define ECX_sig(context)     ((context)->tf_ecx)
 184 #define EDX_sig(context)     ((context)->tf_edx)
 185 #define ESI_sig(context)     ((context)->tf_esi)
 186 #define EDI_sig(context)     ((context)->tf_edi)
 187 #define EBP_sig(context)     ((context)->tf_ebp)
 188
 189 #define CS_sig(context)      ((context)->tf_cs)
 190 #define DS_sig(context)      ((context)->tf_ds)
 191 #define ES_sig(context)      ((context)->tf_es)
 192 #define SS_sig(context)      ((context)->tf_ss)
 193
 194 #include <machine/frame.h>
 195 typedef struct trapframe SIGCONTEXT;
 196
 197 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 198 #define HANDLER_CONTEXT __context
 199
 200 #define EFL_sig(context)     ((context)->tf_eflags)
 201
 202 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 203 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 204
 205 #endif /* bsdi */
 206
 207 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 208
 209 typedef struct sigcontext SIGCONTEXT;
 210
 211 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 212 #define HANDLER_CONTEXT __context
 213
 214 #endif  /* *BSD */
 215
 216 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 217
 218 #ifdef _SCO_DS
 219 #include <sys/regset.h>
 220 #endif
 221 /* Solaris kludge */
 222 #undef ERR
 223 #include <sys/ucontext.h>
 224 #undef ERR
 225 typedef struct ucontext SIGCONTEXT;
 226
 227 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 228 #define HANDLER_CONTEXT __context
 229
 230 #endif  /* svr4 || SCO_DS */
 231
 232 #ifdef __EMX__
 233
 234 typedef struct
 235 {
 236     unsigned long ContextFlags;
 237     FLOATING_SAVE_AREA sc_float;
 238     unsigned long sc_gs;
 239     unsigned long sc_fs;
 240     unsigned long sc_es;
 241     unsigned long sc_ds;
 242     unsigned long sc_edi;
 243     unsigned long sc_esi;
 244     unsigned long sc_eax;
 245     unsigned long sc_ebx;
 246     unsigned long sc_ecx;
 247     unsigned long sc_edx;
 248     unsigned long sc_ebp;
 249     unsigned long sc_eip;
 250     unsigned long sc_cs;
 251     unsigned long sc_eflags;
 252     unsigned long sc_esp;
 253     unsigned long sc_ss;
 254 } SIGCONTEXT;
 255
 256 #endif  /* __EMX__ */
 257
 258 #ifdef __CYGWIN__
 259
 260 /* FIXME: This section is just here so it can compile, it's most likely
 261  * completely wrong. */
 262
 263 typedef struct
 264 {
 265     unsigned short sc_gs, __gsh;
 266     unsigned short sc_fs, __fsh;
 267     unsigned short sc_es, __esh;
 268     unsigned short sc_ds, __dsh;
 269     unsigned long sc_edi;
 270     unsigned long sc_esi;
 271     unsigned long sc_ebp;
 272     unsigned long sc_esp;
 273     unsigned long sc_ebx;
 274     unsigned long sc_edx;
 275     unsigned long sc_ecx;
 276     unsigned long sc_eax;
 277     unsigned long sc_trapno;
 278     unsigned long sc_err;
 279     unsigned long sc_eip;
 280     unsigned short sc_cs, __csh;
 281     unsigned long sc_eflags;
 282     unsigned long esp_at_signal;
 283     unsigned short sc_ss, __ssh;
 284     unsigned long i387;
 285     unsigned long oldmask;
 286     unsigned long cr2;
 287 } SIGCONTEXT;
 288
 289 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
 290 #define HANDLER_CONTEXT (&__context)
 291
 292 #endif /* __CYGWIN__ */
 293
 294 #ifdef __APPLE__
 295 # include <sys/ucontext.h>
 296 # include <sys/types.h>
 297 # include <signal.h>
 298
 299 typedef ucontext_t SIGCONTEXT;
 300
 301 #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
 302 #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
 303 #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
 304 #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
 305 #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
 306 #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
 307 #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
 308
 309 #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
 310 #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
 311 #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
 312 #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
 313 #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
 314 #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
 315
 316 #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
 317
 318 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
 319 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
 320
 321 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 322 #define HANDLER_CONTEXT (__context)
 323
 324 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 325 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 326
 327 #define FAULT_ADDRESS        (__siginfo->si_addr)
 328
 329 #endif /* __APPLE__ */
 330
 331 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) ||\
 332     defined(__OpenBSD__) || defined(__EMX__) || defined(__CYGWIN__)
 333
 334 #define EAX_sig(context)     ((context)->sc_eax)
 335 #define EBX_sig(context)     ((context)->sc_ebx)
 336 #define ECX_sig(context)     ((context)->sc_ecx)
 337 #define EDX_sig(context)     ((context)->sc_edx)
 338 #define ESI_sig(context)     ((context)->sc_esi)
 339 #define EDI_sig(context)     ((context)->sc_edi)
 340 #define EBP_sig(context)     ((context)->sc_ebp)
 341
 342 #define CS_sig(context)      ((context)->sc_cs)
 343 #define DS_sig(context)      ((context)->sc_ds)
 344 #define ES_sig(context)      ((context)->sc_es)
 345 #define FS_sig(context)      ((context)->sc_fs)
 346 #define GS_sig(context)      ((context)->sc_gs)
 347 #define SS_sig(context)      ((context)->sc_ss)
 348
 349 #define TRAP_sig(context)    ((context)->sc_trapno)
 350
 351 #ifdef __NetBSD__
 352 #define ERROR_sig(context)   ((context)->sc_err)
 353 #endif
 354
 355 #ifdef linux
 356 #define ERROR_sig(context)   ((context)->sc_err)
 357 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 358 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->cr2)
 359 #endif
 360
 361 #ifdef __FreeBSD__
 362 #define EFL_sig(context)     ((context)->sc_efl)
 363 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 364 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->sc_err)
 365 #else
 366 #define EFL_sig(context)     ((context)->sc_eflags)
 367 #endif
 368
 369 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 370 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 371
 372 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 373
 374 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 375
 376 #ifdef _SCO_DS
 377 #define gregs regs
 378 #endif
 379
 380 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 381 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 382 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 383 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 384 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 385 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 386 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 387
 388 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 389 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 390 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 391 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 392
 393 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 394 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 395
 396 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 397
 398 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 399 #ifdef UESP
 400 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 401 #elif defined(R_ESP)
 402 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 403 #else
 404 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 405 #endif
 406 #ifdef TRAPNO
 407 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 408 #endif
 409
 410 #define FAULT_ADDRESS         (__siginfo->si_addr)
 411
 412 #endif  /* svr4 || SCO_DS */
 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 size_t signal_stack_mask;
 451 static size_t signal_stack_size;
 452
 453 static wine_signal_handler handlers[256];
 454
 455 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( const CONTEXT *context );
 456
 457
 458 /***********************************************************************
 459  *           dispatch_signal
 460  */
 461 inline static int dispatch_signal(unsigned int sig)
 462 {
 463     if (handlers[sig] == NULL) return 0;
 464     return handlers[sig](sig);
 465 }
 466
 467
 468 /***********************************************************************
 469  *           get_trap_code
 470  *
 471  * Get the trap code for a signal.
 472  */
 473 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 474 {
 475 #ifdef TRAP_sig
 476     return TRAP_sig(sigcontext);
 477 #else
 478     return T_UNKNOWN;  /* unknown trap code */
 479 #endif
 480 }
 481
 482 /***********************************************************************
 483  *           get_error_code
 484  *
 485  * Get the error code for a signal.
 486  */
 487 static inline WORD get_error_code( const SIGCONTEXT *sigcontext )
 488 {
 489 #ifdef ERROR_sig
 490     return ERROR_sig(sigcontext);
 491 #else
 492     return 0;
 493 #endif
 494 }
 495
 496 /***********************************************************************
 497  *           get_signal_stack
 498  *
 499  * Get the base of the signal stack for the current thread.
 500  */
 501 static inline void *get_signal_stack(void)
 502 {
 503     return (char *)NtCurrentTeb() + 4096;
 504 }
 505
 506
 507 /***********************************************************************
 508  *           get_current_teb
 509  *
 510  * Get the current teb based on the stack pointer.
 511  */
 512 static inline TEB *get_current_teb(void)
 513 {
 514     unsigned long esp;
 515     __asm__("movl %%esp,%0" : "=g" (esp) );
 516     return (TEB *)(esp & ~signal_stack_mask);
 517 }
 518
 519
 520 #ifdef __HAVE_VM86
 521 /***********************************************************************
 522  *           save_vm86_context
 523  *
 524  * Set the register values from a vm86 structure.
 525  */
 526 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 527 {
 528     context->Eax    = vm86->regs.eax;
 529     context->Ebx    = vm86->regs.ebx;
 530     context->Ecx    = vm86->regs.ecx;
 531     context->Edx    = vm86->regs.edx;
 532     context->Esi    = vm86->regs.esi;
 533     context->Edi    = vm86->regs.edi;
 534     context->Esp    = vm86->regs.esp;
 535     context->Ebp    = vm86->regs.ebp;
 536     context->Eip    = vm86->regs.eip;
 537     context->SegCs  = vm86->regs.cs;
 538     context->SegDs  = vm86->regs.ds;
 539     context->SegEs  = vm86->regs.es;
 540     context->SegFs  = vm86->regs.fs;
 541     context->SegGs  = vm86->regs.gs;
 542     context->SegSs  = vm86->regs.ss;
 543     context->EFlags = vm86->regs.eflags;
 544 }
 545
 546
 547 /***********************************************************************
 548  *           restore_vm86_context
 549  *
 550  * Build a vm86 structure from the register values.
 551  */
 552 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 553 {
 554     vm86->regs.eax    = context->Eax;
 555     vm86->regs.ebx    = context->Ebx;
 556     vm86->regs.ecx    = context->Ecx;
 557     vm86->regs.edx    = context->Edx;
 558     vm86->regs.esi    = context->Esi;
 559     vm86->regs.edi    = context->Edi;
 560     vm86->regs.esp    = context->Esp;
 561     vm86->regs.ebp    = context->Ebp;
 562     vm86->regs.eip    = context->Eip;
 563     vm86->regs.cs     = context->SegCs;
 564     vm86->regs.ds     = context->SegDs;
 565     vm86->regs.es     = context->SegEs;
 566     vm86->regs.fs     = context->SegFs;
 567     vm86->regs.gs     = context->SegGs;
 568     vm86->regs.ss     = context->SegSs;
 569     vm86->regs.eflags = context->EFlags;
 570 }
 571
 572
 573 /**********************************************************************
 574  *              merge_vm86_pending_flags
 575  *
 576  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 577  * raises exception if there are pending events and VIF flag
 578  * has been turned on.
 579  *
 580  * Called from __wine_enter_vm86 because vm86_enter
 581  * doesn't check for pending events.
 582  *
 583  * Called from raise_vm86_sti_exception to check for
 584  * pending events in a signal safe way.
 585  */
 586 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 587 {
 588     BOOL check_pending = TRUE;
 589     struct vm86plus_struct *vm86 =
 590         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 591
 592     /*
 593      * In order to prevent a race when SIGUSR2 occurs while
 594      * we are returning from exception handler, pending events
 595      * will be rechecked after each raised exception.
 596      */
 597     while (check_pending && NtCurrentTeb()->vm86_pending)
 598     {
 599         check_pending = FALSE;
 600         ntdll_get_thread_data()->vm86_ptr = NULL;
 601
 602         /*
 603          * If VIF is set, throw exception.
 604          * Note that SIGUSR2 may turn VIF flag off so
 605          * VIF check must occur only when TEB.vm86_ptr is NULL.
 606          */
 607         if (vm86->regs.eflags & VIF_MASK)
 608         {
 609             CONTEXT vcontext;
 610             save_vm86_context( &vcontext, vm86 );
 611
 612             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 613             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 614             rec->ExceptionRecord  = NULL;
 615             rec->NumberParameters = 0;
 616             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 617
 618             vcontext.EFlags &= ~VIP_MASK;
 619             NtCurrentTeb()->vm86_pending = 0;
 620             __regs_RtlRaiseException( rec, &vcontext );
 621
 622             restore_vm86_context( &vcontext, vm86 );
 623             check_pending = TRUE;
 624         }
 625
 626         ntdll_get_thread_data()->vm86_ptr = vm86;
 627     }
 628
 629     /*
 630      * Merge VIP flags in a signal safe way. This requires
 631      * that the following operation compiles into atomic
 632      * instruction.
 633      */
 634     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 635 }
 636 #endif /* __HAVE_VM86 */
 637
 638
 639 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 640
 641
 642 /***********************************************************************
 643  *           init_handler
 644  *
 645  * Handler initialization when the full context is not needed.
 646  */
 647 inline static void *init_handler( const SIGCONTEXT *sigcontext, WORD *fs, WORD *gs )
 648 {
 649     void *stack = (void *)ESP_sig(sigcontext);
 650     TEB *teb = get_current_teb();
 651     struct ntdll_thread_data *thread_data = (struct ntdll_thread_data *)teb->SystemReserved2;
 652
 653     /* get %fs and %gs at time of the fault */
 654 #ifdef FS_sig
 655     *fs = LOWORD(FS_sig(sigcontext));
 656 #else
 657     *fs = wine_get_fs();
 658 #endif
 659 #ifdef GS_sig
 660     *gs = LOWORD(GS_sig(sigcontext));
 661 #else
 662     *gs = wine_get_gs();
 663 #endif
 664
 665     wine_set_fs( thread_data->teb_sel );
 666
 667     /* now restore a proper %gs for the fault handler */
 668     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 669         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 670     {
 671         /*
 672          * Win16 or DOS protected mode. Note that during switch
 673          * from 16-bit mode to linear mode, CS may be set to system
 674          * segment before FS is restored. Fortunately, in this case
 675          * SS is still non-system segment. This is why both CS and SS
 676          * are checked.
 677          */
 678         wine_set_gs( teb->gs_sel );
 679         stack = teb->WOW32Reserved;
 680     }
 681 #ifdef __HAVE_VM86
 682     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 683     {
 684         unsigned int *int_stack = stack;
 685         /* fetch the saved %gs from the stack */
 686         wine_set_gs( int_stack[0] );
 687     }
 688 #endif
 689     else  /* 32-bit mode */
 690     {
 691 #ifdef GS_sig
 692         wine_set_gs( GS_sig(sigcontext) );
 693 #endif
 694     }
 695     return stack;
 696 }
 697
 698
 699 /***********************************************************************
 700  *           save_fpu
 701  *
 702  * Set the FPU context from a sigcontext.
 703  */
 704 inline static void save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 705 {
 706     context->ContextFlags |= CONTEXT86_FLOATING_POINT;
 707 #ifdef FPU_sig
 708     if (FPU_sig(sigcontext))
 709     {
 710         context->FloatSave = *FPU_sig(sigcontext);
 711         return;
 712     }
 713 #endif  /* FPU_sig */
 714 #ifdef __GNUC__
 715     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 716 #endif  /* __GNUC__ */
 717 }
 718
 719
 720 /***********************************************************************
 721  *           restore_fpu
 722  *
 723  * Restore the FPU context to a sigcontext.
 724  */
 725 inline static void restore_fpu( const CONTEXT *context )
 726 {
 727     FLOATING_SAVE_AREA float_status = context->FloatSave;
 728     /* reset the current interrupt status */
 729     float_status.StatusWord &= float_status.ControlWord | 0xffffff80;
 730 #ifdef __GNUC__
 731     __asm__ __volatile__( "frstor %0; fwait" : : "m" (float_status) );
 732 #endif  /* __GNUC__ */
 733 }
 734
 735
 736 /***********************************************************************
 737  *           save_context
 738  *
 739  * Build a context structure from the signal info.
 740  */
 741 inline static void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext, WORD fs, WORD gs )
 742 {
 743     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 744
 745     context->ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
 746     context->Eax          = EAX_sig(sigcontext);
 747     context->Ebx          = EBX_sig(sigcontext);
 748     context->Ecx          = ECX_sig(sigcontext);
 749     context->Edx          = EDX_sig(sigcontext);
 750     context->Esi          = ESI_sig(sigcontext);
 751     context->Edi          = EDI_sig(sigcontext);
 752     context->Ebp          = EBP_sig(sigcontext);
 753     context->EFlags       = EFL_sig(sigcontext);
 754     context->Eip          = EIP_sig(sigcontext);
 755     context->Esp          = ESP_sig(sigcontext);
 756     context->SegCs        = LOWORD(CS_sig(sigcontext));
 757     context->SegDs        = LOWORD(DS_sig(sigcontext));
 758     context->SegEs        = LOWORD(ES_sig(sigcontext));
 759     context->SegFs        = fs;
 760     context->SegGs        = gs;
 761     context->SegSs        = LOWORD(SS_sig(sigcontext));
 762     context->Dr0          = regs->dr0;
 763     context->Dr1          = regs->dr1;
 764     context->Dr2          = regs->dr2;
 765     context->Dr3          = regs->dr3;
 766     context->Dr6          = regs->dr6;
 767     context->Dr7          = regs->dr7;
 768 }
 769
 770
 771 /***********************************************************************
 772  *           restore_context
 773  *
 774  * Restore the signal info from the context.
 775  */
 776 inline static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 777 {
 778     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 779
 780     regs->dr0 = context->Dr0;
 781     regs->dr1 = context->Dr1;
 782     regs->dr2 = context->Dr2;
 783     regs->dr3 = context->Dr3;
 784     regs->dr6 = context->Dr6;
 785     regs->dr7 = context->Dr7;
 786     EAX_sig(sigcontext) = context->Eax;
 787     EBX_sig(sigcontext) = context->Ebx;
 788     ECX_sig(sigcontext) = context->Ecx;
 789     EDX_sig(sigcontext) = context->Edx;
 790     ESI_sig(sigcontext) = context->Esi;
 791     EDI_sig(sigcontext) = context->Edi;
 792     EBP_sig(sigcontext) = context->Ebp;
 793     EFL_sig(sigcontext) = context->EFlags;
 794     EIP_sig(sigcontext) = context->Eip;
 795     ESP_sig(sigcontext) = context->Esp;
 796     CS_sig(sigcontext)  = context->SegCs;
 797     DS_sig(sigcontext)  = context->SegDs;
 798     ES_sig(sigcontext)  = context->SegEs;
 799     SS_sig(sigcontext)  = context->SegSs;
 800 #ifdef GS_sig
 801     GS_sig(sigcontext)  = context->SegGs;
 802 #else
 803     wine_set_gs( context->SegGs );
 804 #endif
 805 #ifdef FS_sig
 806     FS_sig(sigcontext)  = context->SegFs;
 807 #else
 808     wine_set_fs( context->SegFs );
 809 #endif
 810 }
 811
 812
 813 /***********************************************************************
 814  *           set_cpu_context
 815  *
 816  * Set the new CPU context. Used by NtSetContextThread.
 817  */
 818 void set_cpu_context( const CONTEXT *context )
 819 {
 820     DWORD flags = context->ContextFlags & ~CONTEXT_i386;
 821
 822     if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
 823
 824     if (flags & CONTEXT_DEBUG_REGISTERS)
 825     {
 826         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 827         regs->dr0 = context->Dr0;
 828         regs->dr1 = context->Dr1;
 829         regs->dr2 = context->Dr2;
 830         regs->dr3 = context->Dr3;
 831         regs->dr6 = context->Dr6;
 832         regs->dr7 = context->Dr7;
 833     }
 834     if (flags & CONTEXT_FULL)
 835     {
 836         if ((flags & CONTEXT_FULL) != (CONTEXT_FULL & ~CONTEXT_i386))
 837             FIXME( "setting partial context (%lx) not supported\n", flags );
 838         else
 839             __wine_call_from_32_restore_regs( context );
 840     }
 841 }
 842
 843
 844 /***********************************************************************
 845  *           is_privileged_instr
 846  *
 847  * Check if the fault location is a privileged instruction.
 848  * Based on the instruction emulation code in dlls/kernel/instr.c.
 849  */
 850 static inline int is_privileged_instr( CONTEXT86 *context )
 851 {
 852     const BYTE *instr;
 853     unsigned int prefix_count = 0;
 854
 855     if (!wine_ldt_is_system( context->SegCs )) return 0;
 856     instr = (BYTE *)context->Eip;
 857
 858     for (;;) switch(*instr)
 859     {
 860     /* instruction prefixes */
 861     case 0x2e:  /* %cs: */
 862     case 0x36:  /* %ss: */
 863     case 0x3e:  /* %ds: */
 864     case 0x26:  /* %es: */
 865     case 0x64:  /* %fs: */
 866     case 0x65:  /* %gs: */
 867     case 0x66:  /* opcode size */
 868     case 0x67:  /* addr size */
 869     case 0xf0:  /* lock */
 870     case 0xf2:  /* repne */
 871     case 0xf3:  /* repe */
 872         if (++prefix_count >= 15) return 0;
 873         instr++;
 874         continue;
 875
 876     case 0x0f: /* extended instruction */
 877         switch(instr[1])
 878         {
 879         case 0x20: /* mov crX, reg */
 880         case 0x21: /* mov drX, reg */
 881         case 0x22: /* mov reg, crX */
 882         case 0x23: /* mov reg drX */
 883             return 1;
 884         }
 885         return 0;
 886     case 0x6c: /* insb (%dx) */
 887     case 0x6d: /* insl (%dx) */
 888     case 0x6e: /* outsb (%dx) */
 889     case 0x6f: /* outsl (%dx) */
 890     case 0xcd: /* int $xx */
 891     case 0xe4: /* inb al,XX */
 892     case 0xe5: /* in (e)ax,XX */
 893     case 0xe6: /* outb XX,al */
 894     case 0xe7: /* out XX,(e)ax */
 895     case 0xec: /* inb (%dx),%al */
 896     case 0xed: /* inl (%dx),%eax */
 897     case 0xee: /* outb %al,(%dx) */
 898     case 0xef: /* outl %eax,(%dx) */
 899     case 0xf4: /* hlt */
 900     case 0xfa: /* cli */
 901     case 0xfb: /* sti */
 902         return 1;
 903     default:
 904         return 0;
 905     }
 906 }
 907
 908
 909 /***********************************************************************
 910  *           setup_exception
 911  *
 912  * Setup a proper stack frame for the raise function, and modify the
 913  * sigcontext so that the return from the signal handler will call
 914  * the raise function.
 915  */
 916 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 917 {
 918     struct stack_layout
 919     {
 920         void             *ret_addr;      /* return address from raise_func */
 921         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 922         CONTEXT          *context_ptr;   /* second arg for raise_func */
 923         CONTEXT           context;
 924         EXCEPTION_RECORD  rec;
 925         DWORD             ebp;
 926         DWORD             eip;
 927     } *stack;
 928
 929     WORD fs, gs;
 930
 931     stack = init_handler( sigcontext, &fs, &gs );
 932
 933     /* stack sanity checks */
 934
 935     if ((char *)stack >= (char *)get_signal_stack() &&
 936         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
 937     {
 938         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 939              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 940              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 941         server_abort_thread(1);
 942     }
 943
 944     if (stack - 1 > stack || /* check for overflow in subtraction */
 945         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
 946         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 947     {
 948         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
 949         if (diff < 4096)
 950         {
 951             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 952                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 953                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 954             server_abort_thread(1);
 955         }
 956         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 957                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 958                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 959     }
 960
 961     stack--;  /* push the stack_layout structure */
 962     stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
 963     stack->rec_ptr      = &stack->rec;
 964     stack->context_ptr  = &stack->context;
 965
 966     stack->rec.ExceptionRecord  = NULL;
 967     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 968     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 969     stack->rec.NumberParameters = 0;
 970
 971     save_context( &stack->context, sigcontext, fs, gs );
 972
 973     /* now modify the sigcontext to return to the raise function */
 974     ESP_sig(sigcontext) = (DWORD)stack;
 975     EIP_sig(sigcontext) = (DWORD)func;
 976     EFL_sig(sigcontext) &= ~0x100;  /* clear single-step flag */
 977     CS_sig(sigcontext)  = wine_get_cs();
 978     DS_sig(sigcontext)  = wine_get_ds();
 979     ES_sig(sigcontext)  = wine_get_es();
 980     FS_sig(sigcontext)  = wine_get_fs();
 981     GS_sig(sigcontext)  = wine_get_gs();
 982     SS_sig(sigcontext)  = wine_get_ss();
 983
 984     return stack->rec_ptr;
 985 }
 986
 987
 988 /***********************************************************************
 989  *           get_exception_context
 990  *
 991  * Get a pointer to the context built by setup_exception.
 992  */
 993 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 994 {
 995     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 996 }
 997
 998
 999 /**********************************************************************
1000  *              get_fpu_code
1001  *
1002  * Get the FPU exception code from the FPU status.
1003  */
1004 static inline DWORD get_fpu_code( const CONTEXT *context )
1005 {
1006     DWORD status = context->FloatSave.StatusWord;
1007
1008     if (status & 0x01)  /* IE */
1009     {
1010         if (status & 0x40)  /* SF */
1011             return EXCEPTION_FLT_STACK_CHECK;
1012         else
1013             return EXCEPTION_FLT_INVALID_OPERATION;
1014     }
1015     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
1016     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
1017     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
1018     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
1019     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
1020     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
1021 }
1022
1023
1024 /**********************************************************************
1025  *              raise_segv_exception
1026  */
1027 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1028 {
1029     switch(rec->ExceptionCode)
1030     {
1031     case EXCEPTION_ACCESS_VIOLATION:
1032         if (rec->NumberParameters == 2)
1033             rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] );
1034         break;
1035     case EXCEPTION_DATATYPE_MISALIGNMENT:
1036         /* FIXME: pass through exception handler first? */
1037         if (context->EFlags & 0x00040000)
1038         {
1039             /* Disable AC flag, return */
1040             context->EFlags &= ~0x00040000;
1041             goto done;
1042         }
1043         break;
1044     }
1045     __regs_RtlRaiseException( rec, context );
1046 done:
1047     NtSetContextThread( GetCurrentThread(), context );
1048 }
1049
1050
1051 /**********************************************************************
1052  *              raise_trap_exception
1053  */
1054 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1055 {
1056     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1057     {
1058         if (context->EFlags & 0x100)
1059         {
1060             context->EFlags &= ~0x100;  /* clear single-step flag */
1061         }
1062         else  /* hardware breakpoint, fetch the debug registers */
1063         {
1064             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1065             NtGetContextThread(GetCurrentThread(), context);
1066             /* do we really have a bp from a debug register ?
1067              * if not, then someone did a kill(SIGTRAP) on us, and we
1068              * shall return a breakpoint, not a single step exception
1069              */
1070             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1071             context->ContextFlags |= CONTEXT_FULL;  /* restore flags */
1072         }
1073     }
1074
1075     __regs_RtlRaiseException( rec, context );
1076     NtSetContextThread( GetCurrentThread(), context );
1077 }
1078
1079
1080 /**********************************************************************
1081  *              raise_exception
1082  *
1083  * Generic raise function for exceptions that don't need special treatment.
1084  */
1085 static void WINAPI raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1086 {
1087     __regs_RtlRaiseException( rec, context );
1088     NtSetContextThread( GetCurrentThread(), context );
1089 }
1090
1091
1092 #ifdef __HAVE_VM86
1093 /**********************************************************************
1094  *              raise_vm86_sti_exception
1095  */
1096 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1097 {
1098     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1099     NtCurrentTeb()->vm86_pending |= VIP_MASK;
1100
1101     if (ntdll_get_thread_data()->vm86_ptr)
1102     {
1103         if (((char*)context->Eip >= (char*)vm86_return) &&
1104             ((char*)context->Eip <= (char*)vm86_return_end) &&
1105             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1106             /* exiting from VM86, can't throw */
1107             goto done;
1108         }
1109         merge_vm86_pending_flags( rec );
1110     }
1111     else if (NtCurrentTeb()->dpmi_vif &&
1112              !wine_ldt_is_system(context->SegCs) &&
1113              !wine_ldt_is_system(context->SegSs))
1114     {
1115         /* Executing DPMI code and virtual interrupts are enabled. */
1116         NtCurrentTeb()->vm86_pending = 0;
1117         __regs_RtlRaiseException( rec, context );
1118     }
1119 done:
1120     NtSetContextThread( GetCurrentThread(), context );
1121 }
1122
1123
1124 /**********************************************************************
1125  *              usr2_handler
1126  *
1127  * Handler for SIGUSR2.
1128  * We use it to signal that the running __wine_enter_vm86() should
1129  * immediately set VIP_MASK, causing pending events to be handled
1130  * as early as possible.
1131  */
1132 static HANDLER_DEF(usr2_handler)
1133 {
1134     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
1135     rec->ExceptionCode = EXCEPTION_VM86_STI;
1136 }
1137 #endif /* __HAVE_VM86 */
1138
1139
1140 /**********************************************************************
1141  *              segv_handler
1142  *
1143  * Handler for SIGSEGV and related errors.
1144  */
1145 static HANDLER_DEF(segv_handler)
1146 {
1147     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
1148
1149     switch(get_trap_code(HANDLER_CONTEXT))
1150     {
1151     case T_OFLOW:   /* Overflow exception */
1152         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1153         break;
1154     case T_BOUND:   /* Bound range exception */
1155         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1156         break;
1157     case T_PRIVINFLT:   /* Invalid opcode exception */
1158         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1159         break;
1160     case T_STKFLT:  /* Stack fault */
1161         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1162         break;
1163     case T_SEGNPFLT:  /* Segment not present exception */
1164     case T_PROTFLT:   /* General protection fault */
1165     case T_UNKNOWN:   /* Unknown fault code */
1166         if (!get_error_code(HANDLER_CONTEXT) && is_privileged_instr( get_exception_context(rec) ))
1167             rec->ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1168         else
1169         {
1170             WORD err = get_error_code(HANDLER_CONTEXT);
1171             rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1172             rec->NumberParameters = 2;
1173             rec->ExceptionInformation[0] = 0;
1174             /* if error contains a LDT selector, use that as fault address */
1175             rec->ExceptionInformation[1] = (err & 7) == 4 ? (err & ~7) : 0xffffffff;
1176         }
1177         break;
1178     case T_PAGEFLT:  /* Page fault */
1179         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1180 #ifdef FAULT_ADDRESS
1181         rec->NumberParameters = 2;
1182         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) & 2) != 0;
1183         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1184 #endif
1185         break;
1186     case T_ALIGNFLT:  /* Alignment check exception */
1187         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1188         break;
1189     default:
1190         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1191         /* fall through */
1192     case T_NMI:       /* NMI interrupt */
1193     case T_DNA:       /* Device not available exception */
1194     case T_DOUBLEFLT: /* Double fault exception */
1195     case T_TSSFLT:    /* Invalid TSS exception */
1196     case T_RESERVED:  /* Unknown exception */
1197     case T_MCHK:      /* Machine check exception */
1198 #ifdef T_CACHEFLT
1199     case T_CACHEFLT:  /* Cache flush exception */
1200 #endif
1201         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1202         break;
1203     }
1204 }
1205
1206
1207 /**********************************************************************
1208  *              trap_handler
1209  *
1210  * Handler for SIGTRAP.
1211  */
1212 static HANDLER_DEF(trap_handler)
1213 {
1214     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1215
1216     switch(get_trap_code(HANDLER_CONTEXT))
1217     {
1218     case T_TRCTRAP:  /* Single-step exception */
1219         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1220         break;
1221     case T_BPTFLT:   /* Breakpoint exception */
1222         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1223         /* fall through */
1224     default:
1225         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1226         break;
1227     }
1228 }
1229
1230
1231 /**********************************************************************
1232  *              fpe_handler
1233  *
1234  * Handler for SIGFPE.
1235  */
1236 static HANDLER_DEF(fpe_handler)
1237 {
1238     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1239     CONTEXT *context;
1240
1241     context = get_exception_context( rec );
1242     save_fpu( context, HANDLER_CONTEXT );
1243
1244     switch(get_trap_code(HANDLER_CONTEXT))
1245     {
1246     case T_DIVIDE:   /* Division by zero exception */
1247         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1248         break;
1249     case T_FPOPFLT:   /* Coprocessor segment overrun */
1250         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1251         break;
1252     case T_ARITHTRAP:  /* Floating point exception */
1253     case T_UNKNOWN:    /* Unknown fault code */
1254         rec->ExceptionCode = get_fpu_code( context );
1255         break;
1256     default:
1257         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1258         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1259         break;
1260     }
1261 }
1262
1263
1264 /**********************************************************************
1265  *              int_handler
1266  *
1267  * Handler for SIGINT.
1268  *
1269  * FIXME: should not be calling external functions on the signal stack.
1270  */
1271 static HANDLER_DEF(int_handler)
1272 {
1273     WORD fs, gs;
1274     init_handler( HANDLER_CONTEXT, &fs, &gs );
1275     if (!dispatch_signal(SIGINT))
1276     {
1277         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1278         rec->ExceptionCode = CONTROL_C_EXIT;
1279     }
1280 }
1281
1282 /**********************************************************************
1283  *              abrt_handler
1284  *
1285  * Handler for SIGABRT.
1286  */
1287 static HANDLER_DEF(abrt_handler)
1288 {
1289     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1290     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1291     rec->ExceptionFlags = EH_NONCONTINUABLE;
1292 }
1293
1294
1295 /**********************************************************************
1296  *              term_handler
1297  *
1298  * Handler for SIGTERM.
1299  */
1300 static HANDLER_DEF(term_handler)
1301 {
1302     WORD fs, gs;
1303     init_handler( HANDLER_CONTEXT, &fs, &gs );
1304     server_abort_thread(0);
1305 }
1306
1307
1308 /**********************************************************************
1309  *              usr1_handler
1310  *
1311  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1312  */
1313 static HANDLER_DEF(usr1_handler)
1314 {
1315     WORD fs, gs;
1316     CONTEXT context;
1317
1318     init_handler( HANDLER_CONTEXT, &fs, &gs );
1319     save_context( &context, HANDLER_CONTEXT, fs, gs );
1320     wait_suspend( &context );
1321     restore_context( &context, HANDLER_CONTEXT );
1322 }
1323
1324
1325 /**********************************************************************
1326  *              get_signal_stack_total_size
1327  *
1328  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1329  * Must be a power of two.
1330  */
1331 size_t get_signal_stack_total_size(void)
1332 {
1333     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1334
1335     if (!signal_stack_size)
1336     {
1337         size_t size = 4096, min_size = teb_size + max( MINSIGSTKSZ, 4096 );
1338         /* find the first power of two not smaller than min_size */
1339         while (size < min_size) size *= 2;
1340         signal_stack_mask = size - 1;
1341         signal_stack_size = size - teb_size;
1342     }
1343     return signal_stack_size + teb_size;
1344 }
1345
1346
1347 /***********************************************************************
1348  *           set_handler
1349  *
1350  * Set a signal handler
1351  */
1352 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1353 {
1354     struct sigaction sig_act;
1355
1356 #ifdef linux
1357     if (!have_sigaltstack)
1358     {
1359         struct kernel_sigaction sig_act;
1360         sig_act.ksa_handler = func;
1361         sig_act.ksa_flags   = SA_RESTART;
1362         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1363                               (1 << (SIGUSR1-1)) |
1364                               (1 << (SIGUSR2-1));
1365         /* point to the top of the signal stack */
1366         sig_act.ksa_restorer = (char *)get_signal_stack() + signal_stack_size;
1367         return wine_sigaction( sig, &sig_act, NULL );
1368     }
1369 #endif  /* linux */
1370     sig_act.sa_handler = func;
1371     sigemptyset( &sig_act.sa_mask );
1372     sigaddset( &sig_act.sa_mask, SIGINT );
1373     sigaddset( &sig_act.sa_mask, SIGUSR1 );
1374     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1375
1376 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
1377     sig_act.sa_flags = SA_RESTART;
1378 #elif defined (__svr4__) || defined(_SCO_DS) || defined(__APPLE__)
1379     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1380 #else
1381     sig_act.sa_flags = 0;
1382 #endif
1383
1384 #ifdef SA_ONSTACK
1385     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1386 #endif
1387     return sigaction( sig, &sig_act, NULL );
1388 }
1389
1390
1391 /***********************************************************************
1392  *           __wine_set_signal_handler   (NTDLL.@)
1393  */
1394 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1395 {
1396     if (sig > sizeof(handlers) / sizeof(handlers[0])) return -1;
1397     if (handlers[sig] != NULL) return -2;
1398     handlers[sig] = wsh;
1399     return 0;
1400 }
1401
1402
1403 /**********************************************************************
1404  *              SIGNAL_Init
1405  */
1406 BOOL SIGNAL_Init(void)
1407 {
1408     int have_sigaltstack = 0;
1409
1410 #ifdef HAVE_SIGALTSTACK
1411     struct sigaltstack ss;
1412     ss.ss_sp    = get_signal_stack();
1413     ss.ss_size  = signal_stack_size;
1414     ss.ss_flags = 0;
1415     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1416 #ifdef linux
1417     /* sigaltstack may fail because the kernel is too old, or
1418        because glibc is brain-dead. In the latter case a
1419        direct system call should succeed. */
1420     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1421 #endif  /* linux */
1422 #endif  /* HAVE_SIGALTSTACK */
1423
1424     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1425     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1426     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1427     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1428     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1429     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1430     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1431 #ifdef SIGBUS
1432     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1433 #endif
1434 #ifdef SIGTRAP
1435     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1436 #endif
1437
1438 #ifdef __HAVE_VM86
1439     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1440 #endif
1441
1442     return TRUE;
1443
1444  error:
1445     perror("sigaction");
1446     return FALSE;
1447 }
1448
1449
1450 #ifdef __HAVE_VM86
1451 /**********************************************************************
1452  *              __wine_enter_vm86   (NTDLL.@)
1453  *
1454  * Enter vm86 mode with the specified register context.
1455  */
1456 void __wine_enter_vm86( CONTEXT *context )
1457 {
1458     EXCEPTION_RECORD rec;
1459     int res;
1460     struct vm86plus_struct vm86;
1461
1462     memset( &vm86, 0, sizeof(vm86) );
1463     for (;;)
1464     {
1465         restore_vm86_context( context, &vm86 );
1466
1467         ntdll_get_thread_data()->vm86_ptr = &vm86;
1468         merge_vm86_pending_flags( &rec );
1469
1470         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1471         if (res < 0)
1472         {
1473             errno = -res;
1474             return;
1475         }
1476
1477         save_vm86_context( context, &vm86 );
1478
1479         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1480         rec.ExceptionRecord  = NULL;
1481         rec.ExceptionAddress = (LPVOID)context->Eip;
1482         rec.NumberParameters = 0;
1483
1484         switch(VM86_TYPE(res))
1485         {
1486         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1487             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1488             raise_segv_exception( &rec, context );
1489             continue;
1490         case VM86_TRAP: /* return due to DOS-debugger request */
1491             switch(VM86_ARG(res))
1492             {
1493             case T_TRCTRAP:  /* Single-step exception, single step flag is cleared by raise_trap_exception */
1494                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1495                 break;
1496             case T_BPTFLT:   /* Breakpoint exception */
1497                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1498                 /* fall through */
1499             default:
1500                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1501                 break;
1502             }
1503             raise_trap_exception( &rec, context );
1504             continue;
1505         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1506             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1507             rec.NumberParameters = 1;
1508             rec.ExceptionInformation[0] = VM86_ARG(res);
1509             break;
1510         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1511             context->EFlags |= VIF_MASK;
1512             context->EFlags &= ~VIP_MASK;
1513             NtCurrentTeb()->vm86_pending = 0;
1514             rec.ExceptionCode = EXCEPTION_VM86_STI;
1515             break;
1516         case VM86_PICRETURN: /* return due to pending PIC request */
1517             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1518             break;
1519         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1520         default:
1521             ERR( "unhandled result from vm86 mode %x\n", res );
1522             continue;
1523         }
1524         __regs_RtlRaiseException( &rec, context );
1525     }
1526 }
1527
1528 #else /* __HAVE_VM86 */
1529 /**********************************************************************
1530  *              __wine_enter_vm86   (NTDLL.@)
1531  */
1532 void __wine_enter_vm86( CONTEXT *context )
1533 {
1534     MESSAGE("vm86 mode not supported on this platform\n");
1535 }
1536 #endif /* __HAVE_VM86 */
1537
1538 /**********************************************************************
1539  *              DbgBreakPoint   (NTDLL.@)
1540  */
1541 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1542
1543 /**********************************************************************
1544  *              DbgUserBreakPoint   (NTDLL.@)
1545  */
1546 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1547
1548
1549 /**********************************************************************
1550  *              EXC_CallHandler   (internal)
1551  *
1552  * Some exception handlers depend on EBP to have a fixed position relative to
1553  * the exception frame.
1554  * Shrinker depends on (*1) doing what it does,
1555  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1556  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1557  * function calling the handler having only 5 parameters (*4).
1558  */
1559 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1560 "       pushl   %ebp\n"
1561 "       movl    %esp, %ebp\n"
1562 "       subl    $4,%esp\n"
1563 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1564 "       pushl   24(%ebp)\n"
1565 "       pushl   20(%ebp)\n"
1566 "       pushl   16(%ebp)\n"
1567 "       pushl   12(%ebp)\n"
1568 "       pushl   8(%ebp)\n"
1569 "       call    " __ASM_NAME("call_exception_handler") "\n"
1570 "       leave\n"
1571 "       ret\n"
1572 );
1573 __ASM_GLOBAL_FUNC(call_exception_handler,
1574 "       pushl   %ebp\n"
1575 "       movl    %esp, %ebp\n"
1576 "       subl    $12,%esp\n"
1577 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1578 "       pushl   %edx\n"           /* handler be handled by... */
1579 "       .byte   0x64\n"
1580 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1581 "       .byte   0x64\n"
1582 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1583 "       pushl   20(%ebp)\n"
1584 "       pushl   16(%ebp)\n"
1585 "       pushl   12(%ebp)\n"
1586 "       pushl   8(%ebp)\n"
1587 "       movl    24(%ebp), %ecx\n" /* (*1) */
1588 "       call    *%ecx\n"          /* call handler. (*2) */
1589 "       .byte   0x64\n"
1590 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1591 "       .byte   0x64\n"
1592 "       popl    (0)\n"            /* exception frame. */
1593 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1594 "       popl    %ebp\n"
1595 "       ret     $20\n"            /* (*4) */
1596 );
1597 #endif  /* __i386__ */