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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, 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 #ifdef HAVE_VALGRIND_MEMCHECK_H
  60 #include <valgrind/memcheck.h>
  61 #endif
  62
  63 /***********************************************************************
  64  * signal context platform-specific definitions
  65  */
  66
  67 #ifdef linux
  68 typedef struct
  69 {
  70     unsigned short sc_gs, __gsh;
  71     unsigned short sc_fs, __fsh;
  72     unsigned short sc_es, __esh;
  73     unsigned short sc_ds, __dsh;
  74     unsigned long sc_edi;
  75     unsigned long sc_esi;
  76     unsigned long sc_ebp;
  77     unsigned long sc_esp;
  78     unsigned long sc_ebx;
  79     unsigned long sc_edx;
  80     unsigned long sc_ecx;
  81     unsigned long sc_eax;
  82     unsigned long sc_trapno;
  83     unsigned long sc_err;
  84     unsigned long sc_eip;
  85     unsigned short sc_cs, __csh;
  86     unsigned long sc_eflags;
  87     unsigned long esp_at_signal;
  88     unsigned short sc_ss, __ssh;
  89     unsigned long i387;
  90     unsigned long oldmask;
  91     unsigned long cr2;
  92 } volatile SIGCONTEXT;
  93
  94 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  95 #define HANDLER_CONTEXT (&__context)
  96
  97 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  98 struct kernel_sigaction
  99 {
 100     void (*ksa_handler)();
 101     unsigned long ksa_mask;
 102     unsigned long ksa_flags;
 103     void *ksa_restorer;
 104 };
 105
 106 #ifndef SYS_sigaction
 107 # ifndef __NR_sigaction
 108 #  error The sigaction syscall is part of the Linux i386 ABI, but your headers does not define it. Please raise a bug with your distribution.
 109 # endif
 110 # define SYS_sigaction __NR_sigaction
 111 #endif
 112
 113 /* Similar to the sigaction function in libc, except it leaves alone the
 114    restorer field, which is used to specify the signal stack address */
 115 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
 116                                   struct kernel_sigaction *old )
 117 {
 118     __asm__ __volatile__( "pushl %%ebx\n\t"
 119                           "movl %2,%%ebx\n\t"
 120                           "int $0x80\n\t"
 121                           "popl %%ebx"
 122                           : "=a" (sig)
 123                           : "0" (SYS_sigaction), "S" (sig), "c" (new), "d" (old) );
 124     if (sig>=0) return 0;
 125     errno = -sig;
 126     return -1;
 127 }
 128
 129 #ifdef HAVE_SIGALTSTACK
 130 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
 131 static inline int wine_sigaltstack( const struct sigaltstack *new,
 132                                     struct sigaltstack *old )
 133 {
 134     int ret;
 135     __asm__ __volatile__( "pushl %%ebx\n\t"
 136                           "movl %2,%%ebx\n\t"
 137                           "int $0x80\n\t"
 138                           "popl %%ebx"
 139                           : "=a" (ret)
 140                           : "0" (SYS_sigaltstack), "q" (new), "c" (old) );
 141     if (ret >= 0) return 0;
 142     errno = -ret;
 143     return -1;
 144 }
 145 #endif
 146
 147 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 148
 149 int vm86_enter( void **vm86_ptr );
 150 void vm86_return(void);
 151 void vm86_return_end(void);
 152 __ASM_GLOBAL_FUNC(vm86_enter,
 153                   "pushl %ebp\n\t"
 154                   "movl %esp, %ebp\n\t"
 155                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 156                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 157                   "movl (%ecx),%ecx\n\t"
 158                   "pushl %ebx\n\t"
 159                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 160                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 161                   "pushl %fs\n\t"
 162                   "pushl %gs\n\t"
 163                   "int $0x80\n"
 164                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 165                   __ASM_FUNC("vm86_return") "\n"
 166                   __ASM_NAME("vm86_return") ":\n\t"
 167                   "popl %gs\n\t"
 168                   "popl %fs\n\t"
 169                   "popl %ecx\n\t"
 170                   "popl %ebx\n\t"
 171                   "popl %ebp\n\t"
 172                   "testl %eax,%eax\n\t"
 173                   "jl 0f\n\t"
 174                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 175                   "je " __ASM_NAME("vm86_enter") "\n\t"
 176                   "0:\n\t"
 177                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 178                   "movl $0,(%ecx)\n\t"
 179                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 180                   __ASM_FUNC("vm86_return_end") "\n"
 181                   __ASM_NAME("vm86_return_end") ":\n\t"
 182                   "ret" );
 183
 184 #ifdef HAVE_SYS_VM86_H
 185 # define __HAVE_VM86
 186 #endif
 187
 188 #endif  /* linux */
 189
 190 #ifdef BSDI
 191
 192 #define EAX_sig(context)     ((context)->tf_eax)
 193 #define EBX_sig(context)     ((context)->tf_ebx)
 194 #define ECX_sig(context)     ((context)->tf_ecx)
 195 #define EDX_sig(context)     ((context)->tf_edx)
 196 #define ESI_sig(context)     ((context)->tf_esi)
 197 #define EDI_sig(context)     ((context)->tf_edi)
 198 #define EBP_sig(context)     ((context)->tf_ebp)
 199
 200 #define CS_sig(context)      ((context)->tf_cs)
 201 #define DS_sig(context)      ((context)->tf_ds)
 202 #define ES_sig(context)      ((context)->tf_es)
 203 #define SS_sig(context)      ((context)->tf_ss)
 204
 205 #include <machine/frame.h>
 206 typedef struct trapframe SIGCONTEXT;
 207
 208 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 209 #define HANDLER_CONTEXT __context
 210
 211 #define EFL_sig(context)     ((context)->tf_eflags)
 212
 213 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 214 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 215
 216 #endif /* bsdi */
 217
 218 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 219
 220 typedef struct sigcontext SIGCONTEXT;
 221
 222 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 223 #define HANDLER_CONTEXT __context
 224
 225 #endif  /* *BSD */
 226
 227 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 228
 229 #ifdef _SCO_DS
 230 #include <sys/regset.h>
 231 #endif
 232 /* Solaris kludge */
 233 #undef ERR
 234 #include <sys/ucontext.h>
 235 #undef ERR
 236 typedef struct ucontext SIGCONTEXT;
 237
 238 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 239 #define HANDLER_CONTEXT __context
 240
 241 #endif  /* svr4 || SCO_DS */
 242
 243 #ifdef __EMX__
 244
 245 typedef struct
 246 {
 247     unsigned long ContextFlags;
 248     FLOATING_SAVE_AREA sc_float;
 249     unsigned long sc_gs;
 250     unsigned long sc_fs;
 251     unsigned long sc_es;
 252     unsigned long sc_ds;
 253     unsigned long sc_edi;
 254     unsigned long sc_esi;
 255     unsigned long sc_eax;
 256     unsigned long sc_ebx;
 257     unsigned long sc_ecx;
 258     unsigned long sc_edx;
 259     unsigned long sc_ebp;
 260     unsigned long sc_eip;
 261     unsigned long sc_cs;
 262     unsigned long sc_eflags;
 263     unsigned long sc_esp;
 264     unsigned long sc_ss;
 265 } SIGCONTEXT;
 266
 267 #endif  /* __EMX__ */
 268
 269 #ifdef __CYGWIN__
 270
 271 /* FIXME: This section is just here so it can compile, it's most likely
 272  * completely wrong. */
 273
 274 typedef struct
 275 {
 276     unsigned short sc_gs, __gsh;
 277     unsigned short sc_fs, __fsh;
 278     unsigned short sc_es, __esh;
 279     unsigned short sc_ds, __dsh;
 280     unsigned long sc_edi;
 281     unsigned long sc_esi;
 282     unsigned long sc_ebp;
 283     unsigned long sc_esp;
 284     unsigned long sc_ebx;
 285     unsigned long sc_edx;
 286     unsigned long sc_ecx;
 287     unsigned long sc_eax;
 288     unsigned long sc_trapno;
 289     unsigned long sc_err;
 290     unsigned long sc_eip;
 291     unsigned short sc_cs, __csh;
 292     unsigned long sc_eflags;
 293     unsigned long esp_at_signal;
 294     unsigned short sc_ss, __ssh;
 295     unsigned long i387;
 296     unsigned long oldmask;
 297     unsigned long cr2;
 298 } SIGCONTEXT;
 299
 300 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
 301 #define HANDLER_CONTEXT (&__context)
 302
 303 #endif /* __CYGWIN__ */
 304
 305 #ifdef __APPLE__
 306 # include <sys/ucontext.h>
 307 # include <sys/types.h>
 308 # include <signal.h>
 309
 310 typedef ucontext_t SIGCONTEXT;
 311
 312 #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
 313 #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
 314 #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
 315 #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
 316 #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
 317 #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
 318 #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
 319
 320 #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
 321 #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
 322 #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
 323 #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
 324 #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
 325 #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
 326
 327 #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
 328
 329 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
 330 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
 331
 332 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 333 #define HANDLER_CONTEXT (__context)
 334
 335 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 336 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 337
 338 #define FAULT_ADDRESS        (__siginfo->si_addr)
 339
 340 #endif /* __APPLE__ */
 341
 342 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) ||\
 343     defined(__OpenBSD__) || defined(__EMX__) || defined(__CYGWIN__)
 344
 345 #define EAX_sig(context)     ((context)->sc_eax)
 346 #define EBX_sig(context)     ((context)->sc_ebx)
 347 #define ECX_sig(context)     ((context)->sc_ecx)
 348 #define EDX_sig(context)     ((context)->sc_edx)
 349 #define ESI_sig(context)     ((context)->sc_esi)
 350 #define EDI_sig(context)     ((context)->sc_edi)
 351 #define EBP_sig(context)     ((context)->sc_ebp)
 352
 353 #define CS_sig(context)      ((context)->sc_cs)
 354 #define DS_sig(context)      ((context)->sc_ds)
 355 #define ES_sig(context)      ((context)->sc_es)
 356 #define FS_sig(context)      ((context)->sc_fs)
 357 #define GS_sig(context)      ((context)->sc_gs)
 358 #define SS_sig(context)      ((context)->sc_ss)
 359
 360 #define TRAP_sig(context)    ((context)->sc_trapno)
 361
 362 #ifdef __NetBSD__
 363 #define ERROR_sig(context)   ((context)->sc_err)
 364 #endif
 365
 366 #ifdef linux
 367 #define ERROR_sig(context)   ((context)->sc_err)
 368 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 369 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->cr2)
 370 #endif
 371
 372 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 373 #define EFL_sig(context)     ((context)->sc_efl)
 374 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 375 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->sc_err)
 376 #else
 377 #define EFL_sig(context)     ((context)->sc_eflags)
 378 #endif
 379
 380 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 381 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 382
 383 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 384
 385 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 386
 387 #ifdef _SCO_DS
 388 #define gregs regs
 389 #endif
 390
 391 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 392 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 393 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 394 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 395 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 396 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 397 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 398
 399 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 400 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 401 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 402 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 403
 404 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 405 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 406
 407 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 408
 409 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 410 #ifdef UESP
 411 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 412 #elif defined(R_ESP)
 413 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 414 #else
 415 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 416 #endif
 417 #ifdef TRAPNO
 418 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 419 #endif
 420
 421 #define FAULT_ADDRESS         (__siginfo->si_addr)
 422
 423 #endif  /* svr4 || SCO_DS */
 424
 425 #include "wine/exception.h"
 426 #include "wine/debug.h"
 427
 428 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 429
 430 typedef int (*wine_signal_handler)(unsigned int sig);
 431
 432 static size_t signal_stack_mask;
 433 static size_t signal_stack_size;
 434
 435 static wine_signal_handler handlers[256];
 436
 437 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( const CONTEXT *context );
 438
 439 enum i386_trap_code
 440 {
 441     TRAP_x86_UNKNOWN    = -1,  /* Unknown fault (TRAP_sig not defined) */
 442     TRAP_x86_DIVIDE     = 0,   /* Division by zero exception */
 443     TRAP_x86_TRCTRAP    = 1,   /* Single-step exception */
 444     TRAP_x86_NMI        = 2,   /* NMI interrupt */
 445     TRAP_x86_BPTFLT     = 3,   /* Breakpoint exception */
 446     TRAP_x86_OFLOW      = 4,   /* Overflow exception */
 447     TRAP_x86_BOUND      = 5,   /* Bound range exception */
 448     TRAP_x86_PRIVINFLT  = 6,   /* Invalid opcode exception */
 449     TRAP_x86_DNA        = 7,   /* Device not available exception */
 450     TRAP_x86_DOUBLEFLT  = 8,   /* Double fault exception */
 451     TRAP_x86_FPOPFLT    = 9,   /* Coprocessor segment overrun */
 452     TRAP_x86_TSSFLT     = 10,  /* Invalid TSS exception */
 453     TRAP_x86_SEGNPFLT   = 11,  /* Segment not present exception */
 454     TRAP_x86_STKFLT     = 12,  /* Stack fault */
 455     TRAP_x86_PROTFLT    = 13,  /* General protection fault */
 456     TRAP_x86_PAGEFLT    = 14,  /* Page fault */
 457     TRAP_x86_ARITHTRAP  = 16,  /* Floating point exception */
 458     TRAP_x86_ALIGNFLT   = 17,  /* Alignment check exception */
 459     TRAP_x86_MCHK       = 18,  /* Machine check exception */
 460     TRAP_x86_CACHEFLT   = 19   /* Cache flush exception */
 461 };
 462
 463
 464 /***********************************************************************
 465  *           dispatch_signal
 466  */
 467 inline static int dispatch_signal(unsigned int sig)
 468 {
 469     if (handlers[sig] == NULL) return 0;
 470     return handlers[sig](sig);
 471 }
 472
 473
 474 /***********************************************************************
 475  *           get_trap_code
 476  *
 477  * Get the trap code for a signal.
 478  */
 479 static inline enum i386_trap_code get_trap_code( const SIGCONTEXT *sigcontext )
 480 {
 481 #ifdef TRAP_sig
 482     return TRAP_sig(sigcontext);
 483 #else
 484     return TRAP_x86_UNKNOWN;  /* unknown trap code */
 485 #endif
 486 }
 487
 488 /***********************************************************************
 489  *           get_error_code
 490  *
 491  * Get the error code for a signal.
 492  */
 493 static inline WORD get_error_code( const SIGCONTEXT *sigcontext )
 494 {
 495 #ifdef ERROR_sig
 496     return ERROR_sig(sigcontext);
 497 #else
 498     return 0;
 499 #endif
 500 }
 501
 502 /***********************************************************************
 503  *           get_signal_stack
 504  *
 505  * Get the base of the signal stack for the current thread.
 506  */
 507 static inline void *get_signal_stack(void)
 508 {
 509     return (char *)NtCurrentTeb() + 4096;
 510 }
 511
 512
 513 /***********************************************************************
 514  *           get_current_teb
 515  *
 516  * Get the current teb based on the stack pointer.
 517  */
 518 static inline TEB *get_current_teb(void)
 519 {
 520     unsigned long esp;
 521     __asm__("movl %%esp,%0" : "=g" (esp) );
 522     return (TEB *)(esp & ~signal_stack_mask);
 523 }
 524
 525
 526 #ifdef __HAVE_VM86
 527 /***********************************************************************
 528  *           save_vm86_context
 529  *
 530  * Set the register values from a vm86 structure.
 531  */
 532 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 533 {
 534     context->ContextFlags = CONTEXT_FULL;
 535     context->Eax    = vm86->regs.eax;
 536     context->Ebx    = vm86->regs.ebx;
 537     context->Ecx    = vm86->regs.ecx;
 538     context->Edx    = vm86->regs.edx;
 539     context->Esi    = vm86->regs.esi;
 540     context->Edi    = vm86->regs.edi;
 541     context->Esp    = vm86->regs.esp;
 542     context->Ebp    = vm86->regs.ebp;
 543     context->Eip    = vm86->regs.eip;
 544     context->SegCs  = vm86->regs.cs;
 545     context->SegDs  = vm86->regs.ds;
 546     context->SegEs  = vm86->regs.es;
 547     context->SegFs  = vm86->regs.fs;
 548     context->SegGs  = vm86->regs.gs;
 549     context->SegSs  = vm86->regs.ss;
 550     context->EFlags = vm86->regs.eflags;
 551 }
 552
 553
 554 /***********************************************************************
 555  *           restore_vm86_context
 556  *
 557  * Build a vm86 structure from the register values.
 558  */
 559 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 560 {
 561     vm86->regs.eax    = context->Eax;
 562     vm86->regs.ebx    = context->Ebx;
 563     vm86->regs.ecx    = context->Ecx;
 564     vm86->regs.edx    = context->Edx;
 565     vm86->regs.esi    = context->Esi;
 566     vm86->regs.edi    = context->Edi;
 567     vm86->regs.esp    = context->Esp;
 568     vm86->regs.ebp    = context->Ebp;
 569     vm86->regs.eip    = context->Eip;
 570     vm86->regs.cs     = context->SegCs;
 571     vm86->regs.ds     = context->SegDs;
 572     vm86->regs.es     = context->SegEs;
 573     vm86->regs.fs     = context->SegFs;
 574     vm86->regs.gs     = context->SegGs;
 575     vm86->regs.ss     = context->SegSs;
 576     vm86->regs.eflags = context->EFlags;
 577 }
 578
 579
 580 /**********************************************************************
 581  *              merge_vm86_pending_flags
 582  *
 583  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 584  * raises exception if there are pending events and VIF flag
 585  * has been turned on.
 586  *
 587  * Called from __wine_enter_vm86 because vm86_enter
 588  * doesn't check for pending events.
 589  *
 590  * Called from raise_vm86_sti_exception to check for
 591  * pending events in a signal safe way.
 592  */
 593 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 594 {
 595     BOOL check_pending = TRUE;
 596     struct vm86plus_struct *vm86 =
 597         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 598
 599     /*
 600      * In order to prevent a race when SIGUSR2 occurs while
 601      * we are returning from exception handler, pending events
 602      * will be rechecked after each raised exception.
 603      */
 604     while (check_pending && NtCurrentTeb()->vm86_pending)
 605     {
 606         check_pending = FALSE;
 607         ntdll_get_thread_data()->vm86_ptr = NULL;
 608
 609         /*
 610          * If VIF is set, throw exception.
 611          * Note that SIGUSR2 may turn VIF flag off so
 612          * VIF check must occur only when TEB.vm86_ptr is NULL.
 613          */
 614         if (vm86->regs.eflags & VIF_MASK)
 615         {
 616             CONTEXT vcontext;
 617             save_vm86_context( &vcontext, vm86 );
 618
 619             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 620             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 621             rec->ExceptionRecord  = NULL;
 622             rec->NumberParameters = 0;
 623             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 624
 625             vcontext.EFlags &= ~VIP_MASK;
 626             NtCurrentTeb()->vm86_pending = 0;
 627             __regs_RtlRaiseException( rec, &vcontext );
 628
 629             restore_vm86_context( &vcontext, vm86 );
 630             check_pending = TRUE;
 631         }
 632
 633         ntdll_get_thread_data()->vm86_ptr = vm86;
 634     }
 635
 636     /*
 637      * Merge VIP flags in a signal safe way. This requires
 638      * that the following operation compiles into atomic
 639      * instruction.
 640      */
 641     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 642 }
 643 #endif /* __HAVE_VM86 */
 644
 645
 646 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 647
 648
 649 /***********************************************************************
 650  *           init_handler
 651  *
 652  * Handler initialization when the full context is not needed.
 653  */
 654 inline static void *init_handler( const SIGCONTEXT *sigcontext, WORD *fs, WORD *gs )
 655 {
 656     void *stack = (void *)ESP_sig(sigcontext);
 657     TEB *teb = get_current_teb();
 658     struct ntdll_thread_regs *thread_regs = (struct ntdll_thread_regs *)teb->SpareBytes1;
 659
 660     /* get %fs and %gs at time of the fault */
 661 #ifdef FS_sig
 662     *fs = LOWORD(FS_sig(sigcontext));
 663 #else
 664     *fs = wine_get_fs();
 665 #endif
 666 #ifdef GS_sig
 667     *gs = LOWORD(GS_sig(sigcontext));
 668 #else
 669     *gs = wine_get_gs();
 670 #endif
 671
 672     wine_set_fs( thread_regs->fs );
 673
 674     /* now restore a proper %gs for the fault handler */
 675     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 676         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 677     {
 678         /*
 679          * Win16 or DOS protected mode. Note that during switch
 680          * from 16-bit mode to linear mode, CS may be set to system
 681          * segment before FS is restored. Fortunately, in this case
 682          * SS is still non-system segment. This is why both CS and SS
 683          * are checked.
 684          */
 685         wine_set_gs( thread_regs->gs );
 686         stack = teb->WOW32Reserved;
 687     }
 688 #ifdef __HAVE_VM86
 689     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 690     {
 691         unsigned int *int_stack = stack;
 692         /* fetch the saved %gs from the stack */
 693         wine_set_gs( int_stack[0] );
 694     }
 695 #endif
 696     else  /* 32-bit mode */
 697     {
 698 #ifdef GS_sig
 699         wine_set_gs( GS_sig(sigcontext) );
 700 #endif
 701     }
 702     return stack;
 703 }
 704
 705
 706 /***********************************************************************
 707  *           save_fpu
 708  *
 709  * Save the thread FPU context.
 710  */
 711 inline static void save_fpu( CONTEXT *context )
 712 {
 713 #ifdef __GNUC__
 714     context->ContextFlags |= CONTEXT_FLOATING_POINT;
 715     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 716 #endif
 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     memset(context, 0, sizeof(*context));
 746     context->ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
 747     context->Eax          = EAX_sig(sigcontext);
 748     context->Ebx          = EBX_sig(sigcontext);
 749     context->Ecx          = ECX_sig(sigcontext);
 750     context->Edx          = EDX_sig(sigcontext);
 751     context->Esi          = ESI_sig(sigcontext);
 752     context->Edi          = EDI_sig(sigcontext);
 753     context->Ebp          = EBP_sig(sigcontext);
 754     context->EFlags       = EFL_sig(sigcontext);
 755     context->Eip          = EIP_sig(sigcontext);
 756     context->Esp          = ESP_sig(sigcontext);
 757     context->SegCs        = LOWORD(CS_sig(sigcontext));
 758     context->SegDs        = LOWORD(DS_sig(sigcontext));
 759     context->SegEs        = LOWORD(ES_sig(sigcontext));
 760     context->SegFs        = fs;
 761     context->SegGs        = gs;
 762     context->SegSs        = LOWORD(SS_sig(sigcontext));
 763     context->Dr0          = regs->dr0;
 764     context->Dr1          = regs->dr1;
 765     context->Dr2          = regs->dr2;
 766     context->Dr3          = regs->dr3;
 767     context->Dr6          = regs->dr6;
 768     context->Dr7          = regs->dr7;
 769
 770 #ifdef FPU_sig
 771     if (FPU_sig(sigcontext))
 772     {
 773         context->ContextFlags |= CONTEXT_FLOATING_POINT;
 774         context->FloatSave = *FPU_sig(sigcontext);
 775     }
 776     else
 777 #endif
 778     {
 779         save_fpu( context );
 780     }
 781 }
 782
 783
 784 /***********************************************************************
 785  *           restore_context
 786  *
 787  * Restore the signal info from the context.
 788  */
 789 inline static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 790 {
 791     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 792
 793     regs->dr0 = context->Dr0;
 794     regs->dr1 = context->Dr1;
 795     regs->dr2 = context->Dr2;
 796     regs->dr3 = context->Dr3;
 797     regs->dr6 = context->Dr6;
 798     regs->dr7 = context->Dr7;
 799     EAX_sig(sigcontext) = context->Eax;
 800     EBX_sig(sigcontext) = context->Ebx;
 801     ECX_sig(sigcontext) = context->Ecx;
 802     EDX_sig(sigcontext) = context->Edx;
 803     ESI_sig(sigcontext) = context->Esi;
 804     EDI_sig(sigcontext) = context->Edi;
 805     EBP_sig(sigcontext) = context->Ebp;
 806     EFL_sig(sigcontext) = context->EFlags;
 807     EIP_sig(sigcontext) = context->Eip;
 808     ESP_sig(sigcontext) = context->Esp;
 809     CS_sig(sigcontext)  = context->SegCs;
 810     DS_sig(sigcontext)  = context->SegDs;
 811     ES_sig(sigcontext)  = context->SegEs;
 812     SS_sig(sigcontext)  = context->SegSs;
 813 #ifdef GS_sig
 814     GS_sig(sigcontext)  = context->SegGs;
 815 #else
 816     wine_set_gs( context->SegGs );
 817 #endif
 818 #ifdef FS_sig
 819     FS_sig(sigcontext)  = context->SegFs;
 820 #else
 821     wine_set_fs( context->SegFs );
 822 #endif
 823
 824 #ifdef FPU_sig
 825     if (FPU_sig(sigcontext))
 826     {
 827         *FPU_sig(sigcontext) = context->FloatSave;
 828     }
 829     else
 830 #endif
 831     {
 832         restore_fpu( context );
 833     }
 834 }
 835
 836
 837 /***********************************************************************
 838  *              get_cpu_context
 839  *
 840  * Register function to get the context of the current thread.
 841  */
 842 void WINAPI __regs_get_cpu_context( CONTEXT *context, CONTEXT *regs )
 843 {
 844     *context = *regs;
 845     save_fpu( context );
 846 }
 847 DEFINE_REGS_ENTRYPOINT( get_cpu_context, 4, 4 );
 848
 849
 850 /***********************************************************************
 851  *           set_cpu_context
 852  *
 853  * Set the new CPU context. Used by NtSetContextThread.
 854  */
 855 void set_cpu_context( const CONTEXT *context )
 856 {
 857     DWORD flags = context->ContextFlags & ~CONTEXT_i386;
 858
 859     if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
 860
 861     if (flags & CONTEXT_DEBUG_REGISTERS)
 862     {
 863         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 864         regs->dr0 = context->Dr0;
 865         regs->dr1 = context->Dr1;
 866         regs->dr2 = context->Dr2;
 867         regs->dr3 = context->Dr3;
 868         regs->dr6 = context->Dr6;
 869         regs->dr7 = context->Dr7;
 870     }
 871     if (flags & CONTEXT_FULL)
 872     {
 873         if ((flags & CONTEXT_FULL) != (CONTEXT_FULL & ~CONTEXT_i386))
 874             FIXME( "setting partial context (%lx) not supported\n", flags );
 875         else
 876             __wine_call_from_32_restore_regs( context );
 877     }
 878 }
 879
 880
 881 /***********************************************************************
 882  *           is_privileged_instr
 883  *
 884  * Check if the fault location is a privileged instruction.
 885  * Based on the instruction emulation code in dlls/kernel/instr.c.
 886  */
 887 static inline int is_privileged_instr( CONTEXT86 *context )
 888 {
 889     const BYTE *instr;
 890     unsigned int prefix_count = 0;
 891
 892     if (!wine_ldt_is_system( context->SegCs )) return 0;
 893     instr = (BYTE *)context->Eip;
 894
 895     for (;;) switch(*instr)
 896     {
 897     /* instruction prefixes */
 898     case 0x2e:  /* %cs: */
 899     case 0x36:  /* %ss: */
 900     case 0x3e:  /* %ds: */
 901     case 0x26:  /* %es: */
 902     case 0x64:  /* %fs: */
 903     case 0x65:  /* %gs: */
 904     case 0x66:  /* opcode size */
 905     case 0x67:  /* addr size */
 906     case 0xf0:  /* lock */
 907     case 0xf2:  /* repne */
 908     case 0xf3:  /* repe */
 909         if (++prefix_count >= 15) return 0;
 910         instr++;
 911         continue;
 912
 913     case 0x0f: /* extended instruction */
 914         switch(instr[1])
 915         {
 916         case 0x20: /* mov crX, reg */
 917         case 0x21: /* mov drX, reg */
 918         case 0x22: /* mov reg, crX */
 919         case 0x23: /* mov reg drX */
 920             return 1;
 921         }
 922         return 0;
 923     case 0x6c: /* insb (%dx) */
 924     case 0x6d: /* insl (%dx) */
 925     case 0x6e: /* outsb (%dx) */
 926     case 0x6f: /* outsl (%dx) */
 927     case 0xcd: /* int $xx */
 928     case 0xe4: /* inb al,XX */
 929     case 0xe5: /* in (e)ax,XX */
 930     case 0xe6: /* outb XX,al */
 931     case 0xe7: /* out XX,(e)ax */
 932     case 0xec: /* inb (%dx),%al */
 933     case 0xed: /* inl (%dx),%eax */
 934     case 0xee: /* outb %al,(%dx) */
 935     case 0xef: /* outl %eax,(%dx) */
 936     case 0xf4: /* hlt */
 937     case 0xfa: /* cli */
 938     case 0xfb: /* sti */
 939         return 1;
 940     default:
 941         return 0;
 942     }
 943 }
 944
 945
 946 #include "pshpack1.h"
 947 struct atl_thunk
 948 {
 949     DWORD movl;  /* movl this,4(%esp) */
 950     DWORD this;
 951     BYTE  jmp;   /* jmp func */
 952     int   func;
 953 };
 954 #include "poppack.h"
 955
 956 /**********************************************************************
 957  *              check_atl_thunk
 958  *
 959  * Check if code destination is an ATL thunk, and emulate it if so.
 960  */
 961 static BOOL check_atl_thunk( EXCEPTION_RECORD *rec, CONTEXT *context )
 962 {
 963     struct atl_thunk *thunk = (struct atl_thunk *)rec->ExceptionInformation[1];
 964
 965     if (thunk->movl != 0x042444c7 || thunk->jmp != 0xe9) return FALSE;
 966     *((DWORD *)context->Esp + 1) = thunk->this;
 967     context->Eip = (DWORD_PTR)(&thunk->func + 1) + thunk->func;
 968     TRACE( "emulating ATL thunk at %p, func=%08lx arg=%08lx\n",
 969            thunk, context->Eip, *((DWORD *)context->Esp + 1) );
 970     return TRUE;
 971 }
 972
 973
 974 /***********************************************************************
 975  *           setup_exception
 976  *
 977  * Setup a proper stack frame for the raise function, and modify the
 978  * sigcontext so that the return from the signal handler will call
 979  * the raise function.
 980  */
 981 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 982 {
 983     struct stack_layout
 984     {
 985         void             *ret_addr;      /* return address from raise_func */
 986         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 987         CONTEXT          *context_ptr;   /* second arg for raise_func */
 988         CONTEXT           context;
 989         EXCEPTION_RECORD  rec;
 990         DWORD             ebp;
 991         DWORD             eip;
 992     } *stack;
 993
 994     WORD fs, gs;
 995
 996     stack = init_handler( sigcontext, &fs, &gs );
 997
 998     /* stack sanity checks */
 999
1000     if ((char *)stack >= (char *)get_signal_stack() &&
1001         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
1002     {
1003         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
1004              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
1005              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
1006         server_abort_thread(1);
1007     }
1008
1009     if (stack - 1 > stack || /* check for overflow in subtraction */
1010         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
1011         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
1012     {
1013         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
1014         if (diff < 4096)
1015         {
1016             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
1017                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
1018                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
1019             server_abort_thread(1);
1020         }
1021         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
1022                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
1023                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
1024     }
1025
1026     stack--;  /* push the stack_layout structure */
1027 #ifdef HAVE_VALGRIND_MEMCHECK_H
1028     VALGRIND_MAKE_WRITABLE(stack, sizeof(*stack));
1029 #endif
1030     stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
1031     stack->rec_ptr      = &stack->rec;
1032     stack->context_ptr  = &stack->context;
1033
1034     stack->rec.ExceptionRecord  = NULL;
1035     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1036     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
1037     stack->rec.NumberParameters = 0;
1038
1039     save_context( &stack->context, sigcontext, fs, gs );
1040
1041     /* now modify the sigcontext to return to the raise function */
1042     ESP_sig(sigcontext) = (DWORD)stack;
1043     EIP_sig(sigcontext) = (DWORD)func;
1044     EFL_sig(sigcontext) &= ~0x100;  /* clear single-step flag */
1045     CS_sig(sigcontext)  = wine_get_cs();
1046     DS_sig(sigcontext)  = wine_get_ds();
1047     ES_sig(sigcontext)  = wine_get_es();
1048     FS_sig(sigcontext)  = wine_get_fs();
1049     GS_sig(sigcontext)  = wine_get_gs();
1050     SS_sig(sigcontext)  = wine_get_ss();
1051
1052     return stack->rec_ptr;
1053 }
1054
1055
1056 /***********************************************************************
1057  *           get_exception_context
1058  *
1059  * Get a pointer to the context built by setup_exception.
1060  */
1061 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
1062 {
1063     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
1064 }
1065
1066
1067 /**********************************************************************
1068  *              get_fpu_code
1069  *
1070  * Get the FPU exception code from the FPU status.
1071  */
1072 static inline DWORD get_fpu_code( const CONTEXT *context )
1073 {
1074     DWORD status = context->FloatSave.StatusWord;
1075
1076     if (status & 0x01)  /* IE */
1077     {
1078         if (status & 0x40)  /* SF */
1079             return EXCEPTION_FLT_STACK_CHECK;
1080         else
1081             return EXCEPTION_FLT_INVALID_OPERATION;
1082     }
1083     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
1084     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
1085     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
1086     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
1087     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
1088     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
1089 }
1090
1091
1092 /**********************************************************************
1093  *              raise_segv_exception
1094  */
1095 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1096 {
1097     switch(rec->ExceptionCode)
1098     {
1099     case EXCEPTION_ACCESS_VIOLATION:
1100         if (rec->NumberParameters == 2)
1101         {
1102             if ((rec->ExceptionInformation[0] == 8) && check_atl_thunk( rec, context )) goto done;
1103             rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] );
1104         }
1105         break;
1106     case EXCEPTION_DATATYPE_MISALIGNMENT:
1107         /* FIXME: pass through exception handler first? */
1108         if (context->EFlags & 0x00040000)
1109         {
1110             /* Disable AC flag, return */
1111             context->EFlags &= ~0x00040000;
1112             goto done;
1113         }
1114         break;
1115     }
1116     __regs_RtlRaiseException( rec, context );
1117 done:
1118     NtSetContextThread( GetCurrentThread(), context );
1119 }
1120
1121
1122 /**********************************************************************
1123  *              raise_trap_exception
1124  */
1125 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1126 {
1127     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1128     {
1129         if (context->EFlags & 0x100)
1130         {
1131             context->EFlags &= ~0x100;  /* clear single-step flag */
1132         }
1133         else  /* hardware breakpoint, fetch the debug registers */
1134         {
1135             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1136             NtGetContextThread(GetCurrentThread(), context);
1137             /* do we really have a bp from a debug register ?
1138              * if not, then someone did a kill(SIGTRAP) on us, and we
1139              * shall return a breakpoint, not a single step exception
1140              */
1141             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1142             context->ContextFlags |= CONTEXT_FULL;  /* restore flags */
1143         }
1144     }
1145
1146     __regs_RtlRaiseException( rec, context );
1147     NtSetContextThread( GetCurrentThread(), context );
1148 }
1149
1150
1151 /**********************************************************************
1152  *              raise_exception
1153  *
1154  * Generic raise function for exceptions that don't need special treatment.
1155  */
1156 static void WINAPI raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1157 {
1158     __regs_RtlRaiseException( rec, context );
1159     NtSetContextThread( GetCurrentThread(), context );
1160 }
1161
1162
1163 #ifdef __HAVE_VM86
1164 /**********************************************************************
1165  *              raise_vm86_sti_exception
1166  */
1167 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1168 {
1169     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1170     NtCurrentTeb()->vm86_pending |= VIP_MASK;
1171
1172     if (ntdll_get_thread_data()->vm86_ptr)
1173     {
1174         if (((char*)context->Eip >= (char*)vm86_return) &&
1175             ((char*)context->Eip <= (char*)vm86_return_end) &&
1176             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1177             /* exiting from VM86, can't throw */
1178             goto done;
1179         }
1180         merge_vm86_pending_flags( rec );
1181     }
1182     else if (NtCurrentTeb()->dpmi_vif &&
1183              !wine_ldt_is_system(context->SegCs) &&
1184              !wine_ldt_is_system(context->SegSs))
1185     {
1186         /* Executing DPMI code and virtual interrupts are enabled. */
1187         NtCurrentTeb()->vm86_pending = 0;
1188         __regs_RtlRaiseException( rec, context );
1189     }
1190 done:
1191     NtSetContextThread( GetCurrentThread(), context );
1192 }
1193
1194
1195 /**********************************************************************
1196  *              usr2_handler
1197  *
1198  * Handler for SIGUSR2.
1199  * We use it to signal that the running __wine_enter_vm86() should
1200  * immediately set VIP_MASK, causing pending events to be handled
1201  * as early as possible.
1202  */
1203 static HANDLER_DEF(usr2_handler)
1204 {
1205     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
1206     rec->ExceptionCode = EXCEPTION_VM86_STI;
1207 }
1208 #endif /* __HAVE_VM86 */
1209
1210
1211 /**********************************************************************
1212  *              segv_handler
1213  *
1214  * Handler for SIGSEGV and related errors.
1215  */
1216 static HANDLER_DEF(segv_handler)
1217 {
1218     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
1219
1220     switch(get_trap_code(HANDLER_CONTEXT))
1221     {
1222     case TRAP_x86_OFLOW:   /* Overflow exception */
1223         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1224         break;
1225     case TRAP_x86_BOUND:   /* Bound range exception */
1226         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1227         break;
1228     case TRAP_x86_PRIVINFLT:   /* Invalid opcode exception */
1229         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1230         break;
1231     case TRAP_x86_STKFLT:  /* Stack fault */
1232         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1233         break;
1234     case TRAP_x86_SEGNPFLT:  /* Segment not present exception */
1235     case TRAP_x86_PROTFLT:   /* General protection fault */
1236     case TRAP_x86_UNKNOWN:   /* Unknown fault code */
1237         if (!get_error_code(HANDLER_CONTEXT) && is_privileged_instr( get_exception_context(rec) ))
1238             rec->ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1239         else
1240         {
1241             WORD err = get_error_code(HANDLER_CONTEXT);
1242             rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1243             rec->NumberParameters = 2;
1244             rec->ExceptionInformation[0] = 0;
1245             /* if error contains a LDT selector, use that as fault address */
1246             rec->ExceptionInformation[1] = (err & 7) == 4 ? (err & ~7) : 0xffffffff;
1247         }
1248         break;
1249     case TRAP_x86_PAGEFLT:  /* Page fault */
1250         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1251 #ifdef FAULT_ADDRESS
1252         rec->NumberParameters = 2;
1253         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) >> 1) & 0x09;
1254         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1255 #endif
1256         break;
1257     case TRAP_x86_ALIGNFLT:  /* Alignment check exception */
1258         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1259         break;
1260     default:
1261         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1262         /* fall through */
1263     case TRAP_x86_NMI:       /* NMI interrupt */
1264     case TRAP_x86_DNA:       /* Device not available exception */
1265     case TRAP_x86_DOUBLEFLT: /* Double fault exception */
1266     case TRAP_x86_TSSFLT:    /* Invalid TSS exception */
1267     case TRAP_x86_MCHK:      /* Machine check exception */
1268     case TRAP_x86_CACHEFLT:  /* Cache flush exception */
1269         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1270         break;
1271     }
1272 }
1273
1274
1275 /**********************************************************************
1276  *              trap_handler
1277  *
1278  * Handler for SIGTRAP.
1279  */
1280 static HANDLER_DEF(trap_handler)
1281 {
1282     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1283
1284     switch(get_trap_code(HANDLER_CONTEXT))
1285     {
1286     case TRAP_x86_TRCTRAP:  /* Single-step exception */
1287         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1288         break;
1289     case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1290         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1291         /* fall through */
1292     default:
1293         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1294         break;
1295     }
1296 }
1297
1298
1299 /**********************************************************************
1300  *              fpe_handler
1301  *
1302  * Handler for SIGFPE.
1303  */
1304 static HANDLER_DEF(fpe_handler)
1305 {
1306     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1307     CONTEXT *context;
1308
1309     context = get_exception_context( rec );
1310
1311     switch(get_trap_code(HANDLER_CONTEXT))
1312     {
1313     case TRAP_x86_DIVIDE:   /* Division by zero exception */
1314         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1315         break;
1316     case TRAP_x86_FPOPFLT:   /* Coprocessor segment overrun */
1317         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1318         break;
1319     case TRAP_x86_ARITHTRAP:  /* Floating point exception */
1320     case TRAP_x86_UNKNOWN:    /* Unknown fault code */
1321         rec->ExceptionCode = get_fpu_code( context );
1322         break;
1323     default:
1324         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1325         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1326         break;
1327     }
1328 }
1329
1330
1331 /**********************************************************************
1332  *              int_handler
1333  *
1334  * Handler for SIGINT.
1335  *
1336  * FIXME: should not be calling external functions on the signal stack.
1337  */
1338 static HANDLER_DEF(int_handler)
1339 {
1340     WORD fs, gs;
1341     init_handler( HANDLER_CONTEXT, &fs, &gs );
1342     if (!dispatch_signal(SIGINT))
1343     {
1344         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1345         rec->ExceptionCode = CONTROL_C_EXIT;
1346     }
1347 }
1348
1349 /**********************************************************************
1350  *              abrt_handler
1351  *
1352  * Handler for SIGABRT.
1353  */
1354 static HANDLER_DEF(abrt_handler)
1355 {
1356     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1357     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1358     rec->ExceptionFlags = EH_NONCONTINUABLE;
1359 }
1360
1361
1362 /**********************************************************************
1363  *              term_handler
1364  *
1365  * Handler for SIGTERM.
1366  */
1367 static HANDLER_DEF(term_handler)
1368 {
1369     WORD fs, gs;
1370     init_handler( HANDLER_CONTEXT, &fs, &gs );
1371     server_abort_thread(0);
1372 }
1373
1374
1375 /**********************************************************************
1376  *              usr1_handler
1377  *
1378  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1379  */
1380 static HANDLER_DEF(usr1_handler)
1381 {
1382     WORD fs, gs;
1383     CONTEXT context;
1384
1385     init_handler( HANDLER_CONTEXT, &fs, &gs );
1386     save_context( &context, HANDLER_CONTEXT, fs, gs );
1387     wait_suspend( &context );
1388     restore_context( &context, HANDLER_CONTEXT );
1389 }
1390
1391
1392 /**********************************************************************
1393  *              get_signal_stack_total_size
1394  *
1395  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1396  * Must be a power of two.
1397  */
1398 size_t get_signal_stack_total_size(void)
1399 {
1400     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1401
1402     if (!signal_stack_size)
1403     {
1404         size_t size = 4096, min_size = teb_size + max( MINSIGSTKSZ, 4096 );
1405         /* find the first power of two not smaller than min_size */
1406         while (size < min_size) size *= 2;
1407         signal_stack_mask = size - 1;
1408         signal_stack_size = size - teb_size;
1409     }
1410     return signal_stack_size + teb_size;
1411 }
1412
1413
1414 /***********************************************************************
1415  *           set_handler
1416  *
1417  * Set a signal handler
1418  */
1419 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1420 {
1421     struct sigaction sig_act;
1422
1423 #ifdef linux
1424     if (!have_sigaltstack)
1425     {
1426         struct kernel_sigaction sig_act;
1427         sig_act.ksa_handler = func;
1428         sig_act.ksa_flags   = SA_RESTART;
1429         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1430                               (1 << (SIGUSR1-1)) |
1431                               (1 << (SIGUSR2-1));
1432         /* point to the top of the signal stack */
1433         sig_act.ksa_restorer = (char *)get_signal_stack() + signal_stack_size;
1434         return wine_sigaction( sig, &sig_act, NULL );
1435     }
1436 #endif  /* linux */
1437     sig_act.sa_handler = func;
1438     sigemptyset( &sig_act.sa_mask );
1439     sigaddset( &sig_act.sa_mask, SIGINT );
1440     sigaddset( &sig_act.sa_mask, SIGUSR1 );
1441     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1442
1443 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
1444     sig_act.sa_flags = SA_RESTART;
1445 #elif defined (__svr4__) || defined(_SCO_DS) || defined(__APPLE__)
1446     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1447 #else
1448     sig_act.sa_flags = 0;
1449 #endif
1450
1451 #ifdef SA_ONSTACK
1452     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1453 #endif
1454     return sigaction( sig, &sig_act, NULL );
1455 }
1456
1457
1458 /***********************************************************************
1459  *           __wine_set_signal_handler   (NTDLL.@)
1460  */
1461 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1462 {
1463     if (sig >= sizeof(handlers) / sizeof(handlers[0])) return -1;
1464     if (handlers[sig] != NULL) return -2;
1465     handlers[sig] = wsh;
1466     return 0;
1467 }
1468
1469
1470 /**********************************************************************
1471  *              SIGNAL_Init
1472  */
1473 BOOL SIGNAL_Init(void)
1474 {
1475     int have_sigaltstack = 0;
1476
1477 #ifdef HAVE_SIGALTSTACK
1478     struct sigaltstack ss;
1479     ss.ss_sp    = get_signal_stack();
1480     ss.ss_size  = signal_stack_size;
1481     ss.ss_flags = 0;
1482     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1483 #ifdef linux
1484     /* sigaltstack may fail because the kernel is too old, or
1485        because glibc is brain-dead. In the latter case a
1486        direct system call should succeed. */
1487     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1488 #endif  /* linux */
1489 #endif  /* HAVE_SIGALTSTACK */
1490
1491     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1492     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1493     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1494     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1495     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1496     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1497     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1498 #ifdef SIGBUS
1499     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1500 #endif
1501 #ifdef SIGTRAP
1502     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1503 #endif
1504
1505 #ifdef __HAVE_VM86
1506     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1507 #endif
1508
1509     return TRUE;
1510
1511  error:
1512     perror("sigaction");
1513     return FALSE;
1514 }
1515
1516
1517 #ifdef __HAVE_VM86
1518 /**********************************************************************
1519  *              __wine_enter_vm86   (NTDLL.@)
1520  *
1521  * Enter vm86 mode with the specified register context.
1522  */
1523 void __wine_enter_vm86( CONTEXT *context )
1524 {
1525     EXCEPTION_RECORD rec;
1526     int res;
1527     struct vm86plus_struct vm86;
1528
1529     memset( &vm86, 0, sizeof(vm86) );
1530     for (;;)
1531     {
1532         restore_vm86_context( context, &vm86 );
1533
1534         ntdll_get_thread_data()->vm86_ptr = &vm86;
1535         merge_vm86_pending_flags( &rec );
1536
1537         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1538         if (res < 0)
1539         {
1540             errno = -res;
1541             return;
1542         }
1543
1544         save_vm86_context( context, &vm86 );
1545
1546         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1547         rec.ExceptionRecord  = NULL;
1548         rec.ExceptionAddress = (LPVOID)context->Eip;
1549         rec.NumberParameters = 0;
1550
1551         switch(VM86_TYPE(res))
1552         {
1553         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1554             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1555             raise_segv_exception( &rec, context );
1556             continue;
1557         case VM86_TRAP: /* return due to DOS-debugger request */
1558             switch(VM86_ARG(res))
1559             {
1560             case TRAP_x86_TRCTRAP:  /* Single-step exception */
1561                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1562                 break;
1563             case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1564                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1565                 /* fall through */
1566             default:
1567                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1568                 break;
1569             }
1570             break;
1571         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1572             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1573             rec.NumberParameters = 1;
1574             rec.ExceptionInformation[0] = VM86_ARG(res);
1575             break;
1576         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1577             context->EFlags |= VIF_MASK;
1578             context->EFlags &= ~VIP_MASK;
1579             NtCurrentTeb()->vm86_pending = 0;
1580             rec.ExceptionCode = EXCEPTION_VM86_STI;
1581             break;
1582         case VM86_PICRETURN: /* return due to pending PIC request */
1583             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1584             break;
1585         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1586         default:
1587             ERR( "unhandled result from vm86 mode %x\n", res );
1588             continue;
1589         }
1590         __regs_RtlRaiseException( &rec, context );
1591     }
1592 }
1593
1594 #else /* __HAVE_VM86 */
1595 /**********************************************************************
1596  *              __wine_enter_vm86   (NTDLL.@)
1597  */
1598 void __wine_enter_vm86( CONTEXT *context )
1599 {
1600     MESSAGE("vm86 mode not supported on this platform\n");
1601 }
1602 #endif /* __HAVE_VM86 */
1603
1604 /**********************************************************************
1605  *              DbgBreakPoint   (NTDLL.@)
1606  */
1607 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1608
1609 /**********************************************************************
1610  *              DbgUserBreakPoint   (NTDLL.@)
1611  */
1612 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1613
1614
1615 /**********************************************************************
1616  *              EXC_CallHandler   (internal)
1617  *
1618  * Some exception handlers depend on EBP to have a fixed position relative to
1619  * the exception frame.
1620  * Shrinker depends on (*1) doing what it does,
1621  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1622  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1623  * function calling the handler having only 5 parameters (*4).
1624  */
1625 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1626 "       pushl   %ebp\n"
1627 "       movl    %esp, %ebp\n"
1628 "       subl    $4,%esp\n"
1629 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1630 "       pushl   24(%ebp)\n"
1631 "       pushl   20(%ebp)\n"
1632 "       pushl   16(%ebp)\n"
1633 "       pushl   12(%ebp)\n"
1634 "       pushl   8(%ebp)\n"
1635 "       call    " __ASM_NAME("call_exception_handler") "\n"
1636 "       leave\n"
1637 "       ret\n"
1638 );
1639 __ASM_GLOBAL_FUNC(call_exception_handler,
1640 "       pushl   %ebp\n"
1641 "       movl    %esp, %ebp\n"
1642 "       subl    $12,%esp\n"
1643 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1644 "       pushl   %edx\n"           /* handler be handled by... */
1645 "       .byte   0x64\n"
1646 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1647 "       .byte   0x64\n"
1648 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1649 "       pushl   20(%ebp)\n"
1650 "       pushl   16(%ebp)\n"
1651 "       pushl   12(%ebp)\n"
1652 "       pushl   8(%ebp)\n"
1653 "       movl    24(%ebp), %ecx\n" /* (*1) */
1654 "       call    *%ecx\n"          /* call handler. (*2) */
1655 "       .byte   0x64\n"
1656 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1657 "       .byte   0x64\n"
1658 "       popl    (0)\n"            /* exception frame. */
1659 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1660 "       popl    %ebp\n"
1661 "       ret     $20\n"            /* (*4) */
1662 );
1663 #endif  /* __i386__ */