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( 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 #ifdef FPU_sig
 707     if (FPU_sig(sigcontext))
 708     {
 709         context->FloatSave = *FPU_sig(sigcontext);
 710         return;
 711     }
 712 #endif  /* FPU_sig */
 713 #ifdef __GNUC__
 714     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 715 #endif  /* __GNUC__ */
 716 }
 717
 718
 719 /***********************************************************************
 720  *           restore_fpu
 721  *
 722  * Restore the FPU context to a sigcontext.
 723  */
 724 inline static void restore_fpu( CONTEXT *context )
 725 {
 726     /* reset the current interrupt status */
 727     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 728 #ifdef __GNUC__
 729     /* avoid nested exceptions */
 730     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 731 #endif  /* __GNUC__ */
 732 }
 733
 734
 735 /***********************************************************************
 736  *           save_context
 737  *
 738  * Build a context structure from the signal info.
 739  */
 740 inline static void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext, WORD fs, WORD gs )
 741 {
 742     context->ContextFlags = CONTEXT_FULL;
 743     context->Eax          = EAX_sig(sigcontext);
 744     context->Ebx          = EBX_sig(sigcontext);
 745     context->Ecx          = ECX_sig(sigcontext);
 746     context->Edx          = EDX_sig(sigcontext);
 747     context->Esi          = ESI_sig(sigcontext);
 748     context->Edi          = EDI_sig(sigcontext);
 749     context->Ebp          = EBP_sig(sigcontext);
 750     context->EFlags       = EFL_sig(sigcontext);
 751     context->Eip          = EIP_sig(sigcontext);
 752     context->Esp          = ESP_sig(sigcontext);
 753     context->SegCs        = LOWORD(CS_sig(sigcontext));
 754     context->SegDs        = LOWORD(DS_sig(sigcontext));
 755     context->SegEs        = LOWORD(ES_sig(sigcontext));
 756     context->SegFs        = fs;
 757     context->SegGs        = gs;
 758     context->SegSs        = LOWORD(SS_sig(sigcontext));
 759 }
 760
 761
 762 /***********************************************************************
 763  *           restore_context
 764  *
 765  * Restore the signal info from the context.
 766  */
 767 inline static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 768 {
 769     EAX_sig(sigcontext) = context->Eax;
 770     EBX_sig(sigcontext) = context->Ebx;
 771     ECX_sig(sigcontext) = context->Ecx;
 772     EDX_sig(sigcontext) = context->Edx;
 773     ESI_sig(sigcontext) = context->Esi;
 774     EDI_sig(sigcontext) = context->Edi;
 775     EBP_sig(sigcontext) = context->Ebp;
 776     EFL_sig(sigcontext) = context->EFlags;
 777     EIP_sig(sigcontext) = context->Eip;
 778     ESP_sig(sigcontext) = context->Esp;
 779     CS_sig(sigcontext)  = context->SegCs;
 780     DS_sig(sigcontext)  = context->SegDs;
 781     ES_sig(sigcontext)  = context->SegEs;
 782     SS_sig(sigcontext)  = context->SegSs;
 783 #ifdef GS_sig
 784     GS_sig(sigcontext)  = context->SegGs;
 785 #else
 786     wine_set_gs( context->SegGs );
 787 #endif
 788 #ifdef FS_sig
 789     FS_sig(sigcontext)  = context->SegFs;
 790 #else
 791     wine_set_fs( context->SegFs );
 792 #endif
 793 }
 794
 795
 796 /***********************************************************************
 797  *           is_privileged_instr
 798  *
 799  * Check if the fault location is a privileged instruction.
 800  * Based on the instruction emulation code in dlls/kernel/instr.c.
 801  */
 802 static inline int is_privileged_instr( CONTEXT86 *context )
 803 {
 804     const BYTE *instr;
 805     unsigned int prefix_count = 0;
 806
 807     if (!wine_ldt_is_system( context->SegCs )) return 0;
 808     instr = (BYTE *)context->Eip;
 809
 810     for (;;) switch(*instr)
 811     {
 812     /* instruction prefixes */
 813     case 0x2e:  /* %cs: */
 814     case 0x36:  /* %ss: */
 815     case 0x3e:  /* %ds: */
 816     case 0x26:  /* %es: */
 817     case 0x64:  /* %fs: */
 818     case 0x65:  /* %gs: */
 819     case 0x66:  /* opcode size */
 820     case 0x67:  /* addr size */
 821     case 0xf0:  /* lock */
 822     case 0xf2:  /* repne */
 823     case 0xf3:  /* repe */
 824         if (++prefix_count >= 15) return 0;
 825         instr++;
 826         continue;
 827
 828     case 0x0f: /* extended instruction */
 829         switch(instr[1])
 830         {
 831         case 0x20: /* mov crX, reg */
 832         case 0x21: /* mov drX, reg */
 833         case 0x22: /* mov reg, crX */
 834         case 0x23: /* mov reg drX */
 835             return 1;
 836         }
 837         return 0;
 838     case 0x6c: /* insb (%dx) */
 839     case 0x6d: /* insl (%dx) */
 840     case 0x6e: /* outsb (%dx) */
 841     case 0x6f: /* outsl (%dx) */
 842     case 0xcd: /* int $xx */
 843     case 0xe4: /* inb al,XX */
 844     case 0xe5: /* in (e)ax,XX */
 845     case 0xe6: /* outb XX,al */
 846     case 0xe7: /* out XX,(e)ax */
 847     case 0xec: /* inb (%dx),%al */
 848     case 0xed: /* inl (%dx),%eax */
 849     case 0xee: /* outb %al,(%dx) */
 850     case 0xef: /* outl %eax,(%dx) */
 851     case 0xf4: /* hlt */
 852     case 0xfa: /* cli */
 853     case 0xfb: /* sti */
 854         return 1;
 855     default:
 856         return 0;
 857     }
 858 }
 859
 860
 861 /***********************************************************************
 862  *           setup_exception
 863  *
 864  * Setup a proper stack frame for the raise function, and modify the
 865  * sigcontext so that the return from the signal handler will call
 866  * the raise function.
 867  */
 868 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 869 {
 870     struct stack_layout
 871     {
 872         void             *ret_addr;      /* return address from raise_func */
 873         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 874         CONTEXT          *context_ptr;   /* second arg for raise_func */
 875         void             *dummy;         /* dummy ret addr for __wine_call_from_32_restore_regs */
 876         CONTEXT           context;
 877         EXCEPTION_RECORD  rec;
 878         DWORD             ebp;
 879         DWORD             eip;
 880     } *stack;
 881
 882     WORD fs, gs;
 883
 884     stack = init_handler( sigcontext, &fs, &gs );
 885
 886     /* stack sanity checks */
 887
 888     if ((char *)stack >= (char *)get_signal_stack() &&
 889         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
 890     {
 891         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 892              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 893              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 894         server_abort_thread(1);
 895     }
 896
 897     if (stack - 1 > stack || /* check for overflow in subtraction */
 898         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
 899         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 900     {
 901         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
 902         if (diff < 4096)
 903         {
 904             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 905                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 906                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 907             server_abort_thread(1);
 908         }
 909         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 910                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 911                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 912     }
 913
 914     stack--;  /* push the stack_layout structure */
 915     stack->ret_addr     = __wine_call_from_32_restore_regs;
 916     stack->rec_ptr      = &stack->rec;
 917     stack->context_ptr  = &stack->context;
 918
 919     stack->rec.ExceptionRecord  = NULL;
 920     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 921     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 922     stack->rec.NumberParameters = 0;
 923
 924     save_context( &stack->context, sigcontext, fs, gs );
 925
 926     /* now modify the sigcontext to return to the raise function */
 927     ESP_sig(sigcontext) = (DWORD)stack;
 928     EIP_sig(sigcontext) = (DWORD)func;
 929     EFL_sig(sigcontext) &= ~0x100;  /* clear single-step flag */
 930     CS_sig(sigcontext)  = wine_get_cs();
 931     DS_sig(sigcontext)  = wine_get_ds();
 932     ES_sig(sigcontext)  = wine_get_es();
 933     FS_sig(sigcontext)  = wine_get_fs();
 934     GS_sig(sigcontext)  = wine_get_gs();
 935     SS_sig(sigcontext)  = wine_get_ss();
 936
 937     return stack->rec_ptr;
 938 }
 939
 940
 941 /***********************************************************************
 942  *           get_exception_context
 943  *
 944  * Get a pointer to the context built by setup_exception.
 945  */
 946 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 947 {
 948     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 949 }
 950
 951
 952 /**********************************************************************
 953  *              get_fpu_code
 954  *
 955  * Get the FPU exception code from the FPU status.
 956  */
 957 static inline DWORD get_fpu_code( const CONTEXT *context )
 958 {
 959     DWORD status = context->FloatSave.StatusWord;
 960
 961     if (status & 0x01)  /* IE */
 962     {
 963         if (status & 0x40)  /* SF */
 964             return EXCEPTION_FLT_STACK_CHECK;
 965         else
 966             return EXCEPTION_FLT_INVALID_OPERATION;
 967     }
 968     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 969     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 970     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 971     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 972     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 973     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 974 }
 975
 976
 977 /**********************************************************************
 978  *              raise_segv_exception
 979  */
 980 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 981 {
 982     switch(rec->ExceptionCode)
 983     {
 984     case EXCEPTION_ACCESS_VIOLATION:
 985         if (rec->NumberParameters == 2)
 986         {
 987             if (!(rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] )))
 988                 return;
 989         }
 990         break;
 991     case EXCEPTION_DATATYPE_MISALIGNMENT:
 992         /* FIXME: pass through exception handler first? */
 993         if (context->EFlags & 0x00040000)
 994         {
 995             /* Disable AC flag, return */
 996             context->EFlags &= ~0x00040000;
 997             return;
 998         }
 999         break;
1000     }
1001     __regs_RtlRaiseException( rec, context );
1002 }
1003
1004
1005 /**********************************************************************
1006  *              raise_trap_exception
1007  */
1008 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1009 {
1010     DWORD dr0, dr1, dr2, dr3, dr6, dr7;
1011
1012     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1013     {
1014         if (context->EFlags & 0x100)
1015         {
1016             context->EFlags &= ~0x100;  /* clear single-step flag */
1017         }
1018         else  /* hardware breakpoint, fetch the debug registers */
1019         {
1020             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1021             NtGetContextThread(GetCurrentThread(), context);
1022             /* do we really have a bp from a debug register ?
1023              * if not, then someone did a kill(SIGTRAP) on us, and we
1024              * shall return a breakpoint, not a single step exception
1025              */
1026             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1027         }
1028     }
1029
1030     dr0 = context->Dr0;
1031     dr1 = context->Dr1;
1032     dr2 = context->Dr2;
1033     dr3 = context->Dr3;
1034     dr6 = context->Dr6;
1035     dr7 = context->Dr7;
1036
1037     __regs_RtlRaiseException( rec, context );
1038
1039     if (dr0 != context->Dr0 || dr1 != context->Dr1 || dr2 != context->Dr2 ||
1040         dr3 != context->Dr3 || dr6 != context->Dr6 || dr7 != context->Dr7)
1041     {
1042         /* the debug registers have changed, set the new values */
1043         context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1044         NtSetContextThread(GetCurrentThread(), context);
1045     }
1046 }
1047
1048
1049 /**********************************************************************
1050  *              raise_fpu_exception
1051  */
1052 static void WINAPI raise_fpu_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1053 {
1054     __regs_RtlRaiseException( rec, context );
1055     restore_fpu( context );
1056 }
1057
1058
1059 #ifdef __HAVE_VM86
1060 /**********************************************************************
1061  *              raise_vm86_sti_exception
1062  */
1063 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1064 {
1065     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1066     NtCurrentTeb()->vm86_pending |= VIP_MASK;
1067
1068     if (ntdll_get_thread_data()->vm86_ptr)
1069     {
1070         if (((char*)context->Eip >= (char*)vm86_return) &&
1071             ((char*)context->Eip <= (char*)vm86_return_end) &&
1072             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1073             /* exiting from VM86, can't throw */
1074             return;
1075         }
1076         merge_vm86_pending_flags( rec );
1077     }
1078     else if (NtCurrentTeb()->dpmi_vif &&
1079              !wine_ldt_is_system(context->SegCs) &&
1080              !wine_ldt_is_system(context->SegSs))
1081     {
1082         /* Executing DPMI code and virtual interrupts are enabled. */
1083         NtCurrentTeb()->vm86_pending = 0;
1084         __regs_RtlRaiseException( rec, context );
1085     }
1086 }
1087
1088
1089 /**********************************************************************
1090  *              usr2_handler
1091  *
1092  * Handler for SIGUSR2.
1093  * We use it to signal that the running __wine_enter_vm86() should
1094  * immediately set VIP_MASK, causing pending events to be handled
1095  * as early as possible.
1096  */
1097 static HANDLER_DEF(usr2_handler)
1098 {
1099     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
1100     rec->ExceptionCode = EXCEPTION_VM86_STI;
1101 }
1102 #endif /* __HAVE_VM86 */
1103
1104
1105 /**********************************************************************
1106  *              segv_handler
1107  *
1108  * Handler for SIGSEGV and related errors.
1109  */
1110 static HANDLER_DEF(segv_handler)
1111 {
1112     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
1113
1114     switch(get_trap_code(HANDLER_CONTEXT))
1115     {
1116     case T_OFLOW:   /* Overflow exception */
1117         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1118         break;
1119     case T_BOUND:   /* Bound range exception */
1120         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1121         break;
1122     case T_PRIVINFLT:   /* Invalid opcode exception */
1123         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1124         break;
1125     case T_STKFLT:  /* Stack fault */
1126         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1127         break;
1128     case T_SEGNPFLT:  /* Segment not present exception */
1129     case T_PROTFLT:   /* General protection fault */
1130     case T_UNKNOWN:   /* Unknown fault code */
1131         if (!get_error_code(HANDLER_CONTEXT) && is_privileged_instr( get_exception_context(rec) ))
1132             rec->ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1133         else
1134         {
1135             WORD err = get_error_code(HANDLER_CONTEXT);
1136             rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1137             rec->NumberParameters = 2;
1138             rec->ExceptionInformation[0] = 0;
1139             /* if error contains a LDT selector, use that as fault address */
1140             rec->ExceptionInformation[1] = (err & 7) == 4 ? (err & ~7) : 0xffffffff;
1141         }
1142         break;
1143     case T_PAGEFLT:  /* Page fault */
1144         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1145 #ifdef FAULT_ADDRESS
1146         rec->NumberParameters = 2;
1147         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) & 2) != 0;
1148         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1149 #endif
1150         break;
1151     case T_ALIGNFLT:  /* Alignment check exception */
1152         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1153         break;
1154     default:
1155         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1156         /* fall through */
1157     case T_NMI:       /* NMI interrupt */
1158     case T_DNA:       /* Device not available exception */
1159     case T_DOUBLEFLT: /* Double fault exception */
1160     case T_TSSFLT:    /* Invalid TSS exception */
1161     case T_RESERVED:  /* Unknown exception */
1162     case T_MCHK:      /* Machine check exception */
1163 #ifdef T_CACHEFLT
1164     case T_CACHEFLT:  /* Cache flush exception */
1165 #endif
1166         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1167         break;
1168     }
1169 }
1170
1171
1172 /**********************************************************************
1173  *              trap_handler
1174  *
1175  * Handler for SIGTRAP.
1176  */
1177 static HANDLER_DEF(trap_handler)
1178 {
1179     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1180
1181     switch(get_trap_code(HANDLER_CONTEXT))
1182     {
1183     case T_TRCTRAP:  /* Single-step exception */
1184         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1185         break;
1186     case T_BPTFLT:   /* Breakpoint exception */
1187         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1188         /* fall through */
1189     default:
1190         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1191         break;
1192     }
1193 }
1194
1195
1196 /**********************************************************************
1197  *              fpe_handler
1198  *
1199  * Handler for SIGFPE.
1200  */
1201 static HANDLER_DEF(fpe_handler)
1202 {
1203     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_fpu_exception );
1204     CONTEXT *context;
1205
1206     context = get_exception_context( rec );
1207     save_fpu( context, HANDLER_CONTEXT );
1208
1209     switch(get_trap_code(HANDLER_CONTEXT))
1210     {
1211     case T_DIVIDE:   /* Division by zero exception */
1212         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1213         break;
1214     case T_FPOPFLT:   /* Coprocessor segment overrun */
1215         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1216         break;
1217     case T_ARITHTRAP:  /* Floating point exception */
1218     case T_UNKNOWN:    /* Unknown fault code */
1219         rec->ExceptionCode = get_fpu_code( context );
1220         break;
1221     default:
1222         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1223         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1224         break;
1225     }
1226 }
1227
1228
1229 /**********************************************************************
1230  *              int_handler
1231  *
1232  * Handler for SIGINT.
1233  *
1234  * FIXME: should not be calling external functions on the signal stack.
1235  */
1236 static HANDLER_DEF(int_handler)
1237 {
1238     WORD fs, gs;
1239     init_handler( HANDLER_CONTEXT, &fs, &gs );
1240     if (!dispatch_signal(SIGINT))
1241     {
1242         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1243         rec->ExceptionCode = CONTROL_C_EXIT;
1244     }
1245 }
1246
1247 /**********************************************************************
1248  *              abrt_handler
1249  *
1250  * Handler for SIGABRT.
1251  */
1252 static HANDLER_DEF(abrt_handler)
1253 {
1254     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, __regs_RtlRaiseException );
1255     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1256     rec->ExceptionFlags = EH_NONCONTINUABLE;
1257 }
1258
1259
1260 /**********************************************************************
1261  *              term_handler
1262  *
1263  * Handler for SIGTERM.
1264  */
1265 static HANDLER_DEF(term_handler)
1266 {
1267     WORD fs, gs;
1268     init_handler( HANDLER_CONTEXT, &fs, &gs );
1269     server_abort_thread(0);
1270 }
1271
1272
1273 /**********************************************************************
1274  *              usr1_handler
1275  *
1276  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1277  */
1278 static HANDLER_DEF(usr1_handler)
1279 {
1280     WORD fs, gs;
1281     CONTEXT context;
1282
1283     init_handler( HANDLER_CONTEXT, &fs, &gs );
1284     save_context( &context, HANDLER_CONTEXT, fs, gs );
1285     wait_suspend( &context );
1286     restore_context( &context, HANDLER_CONTEXT );
1287 }
1288
1289
1290 /**********************************************************************
1291  *              get_signal_stack_total_size
1292  *
1293  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1294  * Must be a power of two.
1295  */
1296 size_t get_signal_stack_total_size(void)
1297 {
1298     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1299
1300     if (!signal_stack_size)
1301     {
1302         size_t size = 4096, min_size = teb_size + max( MINSIGSTKSZ, 4096 );
1303         /* find the first power of two not smaller than min_size */
1304         while (size < min_size) size *= 2;
1305         signal_stack_mask = size - 1;
1306         signal_stack_size = size - teb_size;
1307     }
1308     return signal_stack_size + teb_size;
1309 }
1310
1311
1312 /***********************************************************************
1313  *           set_handler
1314  *
1315  * Set a signal handler
1316  */
1317 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1318 {
1319     struct sigaction sig_act;
1320
1321 #ifdef linux
1322     if (!have_sigaltstack)
1323     {
1324         struct kernel_sigaction sig_act;
1325         sig_act.ksa_handler = func;
1326         sig_act.ksa_flags   = SA_RESTART;
1327         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1328                               (1 << (SIGUSR1-1)) |
1329                               (1 << (SIGUSR2-1));
1330         /* point to the top of the signal stack */
1331         sig_act.ksa_restorer = (char *)get_signal_stack() + signal_stack_size;
1332         return wine_sigaction( sig, &sig_act, NULL );
1333     }
1334 #endif  /* linux */
1335     sig_act.sa_handler = func;
1336     sigemptyset( &sig_act.sa_mask );
1337     sigaddset( &sig_act.sa_mask, SIGINT );
1338     sigaddset( &sig_act.sa_mask, SIGUSR1 );
1339     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1340
1341 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
1342     sig_act.sa_flags = SA_RESTART;
1343 #elif defined (__svr4__) || defined(_SCO_DS) || defined(__APPLE__)
1344     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1345 #else
1346     sig_act.sa_flags = 0;
1347 #endif
1348
1349 #ifdef SA_ONSTACK
1350     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1351 #endif
1352     return sigaction( sig, &sig_act, NULL );
1353 }
1354
1355
1356 /***********************************************************************
1357  *           __wine_set_signal_handler   (NTDLL.@)
1358  */
1359 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1360 {
1361     if (sig > sizeof(handlers) / sizeof(handlers[0])) return -1;
1362     if (handlers[sig] != NULL) return -2;
1363     handlers[sig] = wsh;
1364     return 0;
1365 }
1366
1367
1368 /**********************************************************************
1369  *              SIGNAL_Init
1370  */
1371 BOOL SIGNAL_Init(void)
1372 {
1373     int have_sigaltstack = 0;
1374
1375 #ifdef HAVE_SIGALTSTACK
1376     struct sigaltstack ss;
1377     ss.ss_sp    = get_signal_stack();
1378     ss.ss_size  = signal_stack_size;
1379     ss.ss_flags = 0;
1380     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1381 #ifdef linux
1382     /* sigaltstack may fail because the kernel is too old, or
1383        because glibc is brain-dead. In the latter case a
1384        direct system call should succeed. */
1385     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1386 #endif  /* linux */
1387 #endif  /* HAVE_SIGALTSTACK */
1388
1389     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1390     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1391     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1392     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1393     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1394     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1395     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1396 #ifdef SIGBUS
1397     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1398 #endif
1399 #ifdef SIGTRAP
1400     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1401 #endif
1402
1403 #ifdef __HAVE_VM86
1404     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1405 #endif
1406
1407     return TRUE;
1408
1409  error:
1410     perror("sigaction");
1411     return FALSE;
1412 }
1413
1414
1415 #ifdef __HAVE_VM86
1416 /**********************************************************************
1417  *              __wine_enter_vm86   (NTDLL.@)
1418  *
1419  * Enter vm86 mode with the specified register context.
1420  */
1421 void __wine_enter_vm86( CONTEXT *context )
1422 {
1423     EXCEPTION_RECORD rec;
1424     int res;
1425     struct vm86plus_struct vm86;
1426
1427     memset( &vm86, 0, sizeof(vm86) );
1428     for (;;)
1429     {
1430         restore_vm86_context( context, &vm86 );
1431
1432         ntdll_get_thread_data()->vm86_ptr = &vm86;
1433         merge_vm86_pending_flags( &rec );
1434
1435         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1436         if (res < 0)
1437         {
1438             errno = -res;
1439             return;
1440         }
1441
1442         save_vm86_context( context, &vm86 );
1443
1444         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1445         rec.ExceptionRecord  = NULL;
1446         rec.ExceptionAddress = (LPVOID)context->Eip;
1447         rec.NumberParameters = 0;
1448
1449         switch(VM86_TYPE(res))
1450         {
1451         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1452             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1453             raise_segv_exception( &rec, context );
1454             continue;
1455         case VM86_TRAP: /* return due to DOS-debugger request */
1456             switch(VM86_ARG(res))
1457             {
1458             case T_TRCTRAP:  /* Single-step exception, single step flag is cleared by raise_trap_exception */
1459                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1460                 break;
1461             case T_BPTFLT:   /* Breakpoint exception */
1462                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1463                 /* fall through */
1464             default:
1465                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1466                 break;
1467             }
1468             raise_trap_exception( &rec, context );
1469             continue;
1470         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1471             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1472             rec.NumberParameters = 1;
1473             rec.ExceptionInformation[0] = VM86_ARG(res);
1474             break;
1475         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1476             context->EFlags |= VIF_MASK;
1477             context->EFlags &= ~VIP_MASK;
1478             NtCurrentTeb()->vm86_pending = 0;
1479             rec.ExceptionCode = EXCEPTION_VM86_STI;
1480             break;
1481         case VM86_PICRETURN: /* return due to pending PIC request */
1482             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1483             break;
1484         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1485         default:
1486             ERR( "unhandled result from vm86 mode %x\n", res );
1487             continue;
1488         }
1489         __regs_RtlRaiseException( &rec, context );
1490     }
1491 }
1492
1493 #else /* __HAVE_VM86 */
1494 /**********************************************************************
1495  *              __wine_enter_vm86   (NTDLL.@)
1496  */
1497 void __wine_enter_vm86( CONTEXT *context )
1498 {
1499     MESSAGE("vm86 mode not supported on this platform\n");
1500 }
1501 #endif /* __HAVE_VM86 */
1502
1503 /**********************************************************************
1504  *              DbgBreakPoint   (NTDLL.@)
1505  */
1506 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1507
1508 /**********************************************************************
1509  *              DbgUserBreakPoint   (NTDLL.@)
1510  */
1511 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1512
1513
1514 /**********************************************************************
1515  *              EXC_CallHandler   (internal)
1516  *
1517  * Some exception handlers depend on EBP to have a fixed position relative to
1518  * the exception frame.
1519  * Shrinker depends on (*1) doing what it does,
1520  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1521  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1522  * function calling the handler having only 5 parameters (*4).
1523  */
1524 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1525 "       pushl   %ebp\n"
1526 "       movl    %esp, %ebp\n"
1527 "       subl    $4,%esp\n"
1528 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1529 "       pushl   24(%ebp)\n"
1530 "       pushl   20(%ebp)\n"
1531 "       pushl   16(%ebp)\n"
1532 "       pushl   12(%ebp)\n"
1533 "       pushl   8(%ebp)\n"
1534 "       call    " __ASM_NAME("call_exception_handler") "\n"
1535 "       leave\n"
1536 "       ret\n"
1537 );
1538 __ASM_GLOBAL_FUNC(call_exception_handler,
1539 "       pushl   %ebp\n"
1540 "       movl    %esp, %ebp\n"
1541 "       subl    $12,%esp\n"
1542 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1543 "       pushl   %edx\n"           /* handler be handled by... */
1544 "       .byte   0x64\n"
1545 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1546 "       .byte   0x64\n"
1547 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1548 "       pushl   20(%ebp)\n"
1549 "       pushl   16(%ebp)\n"
1550 "       pushl   12(%ebp)\n"
1551 "       pushl   8(%ebp)\n"
1552 "       movl    24(%ebp), %ecx\n" /* (*1) */
1553 "       call    *%ecx\n"          /* call handler. (*2) */
1554 "       .byte   0x64\n"
1555 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1556 "       .byte   0x64\n"
1557 "       popl    (0)\n"            /* exception frame. */
1558 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1559 "       popl    %ebp\n"
1560 "       ret     $20\n"            /* (*4) */
1561 );
1562 #endif  /* __i386__ */