dlls/ntdll/signal_i386.c

   1 /*
   2  * i386 signal handling routines
   3  *
   4  * Copyright 1999 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #ifdef __i386__
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdlib.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #ifdef HAVE_UNISTD_H
  32 # include <unistd.h>
  33 #endif
  34
  35 #ifdef HAVE_SYS_PARAM_H
  36 # include <sys/param.h>
  37 #endif
  38 #ifdef HAVE_SYSCALL_H
  39 # include <syscall.h>
  40 #else
  41 # ifdef HAVE_SYS_SYSCALL_H
  42 #  include <sys/syscall.h>
  43 # endif
  44 #endif
  45
  46 #ifdef HAVE_SYS_VM86_H
  47 # include <sys/vm86.h>
  48 #endif
  49
  50 #ifdef HAVE_SYS_SIGNAL_H
  51 # include <sys/signal.h>
  52 #endif
  53
  54 #include "windef.h"
  55 #include "thread.h"
  56 #include "wine/library.h"
  57 #include "ntdll_misc.h"
  58
  59 /***********************************************************************
  60  * signal context platform-specific definitions
  61  */
  62
  63 #ifdef linux
  64 typedef struct
  65 {
  66     unsigned short sc_gs, __gsh;
  67     unsigned short sc_fs, __fsh;
  68     unsigned short sc_es, __esh;
  69     unsigned short sc_ds, __dsh;
  70     unsigned long sc_edi;
  71     unsigned long sc_esi;
  72     unsigned long sc_ebp;
  73     unsigned long sc_esp;
  74     unsigned long sc_ebx;
  75     unsigned long sc_edx;
  76     unsigned long sc_ecx;
  77     unsigned long sc_eax;
  78     unsigned long sc_trapno;
  79     unsigned long sc_err;
  80     unsigned long sc_eip;
  81     unsigned short sc_cs, __csh;
  82     unsigned long sc_eflags;
  83     unsigned long esp_at_signal;
  84     unsigned short sc_ss, __ssh;
  85     unsigned long i387;
  86     unsigned long oldmask;
  87     unsigned long cr2;
  88 } volatile SIGCONTEXT;
  89
  90 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  91 #define HANDLER_CONTEXT (&__context)
  92
  93 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  94 struct kernel_sigaction
  95 {
  96     void (*ksa_handler)();
  97     unsigned long ksa_mask;
  98     unsigned long ksa_flags;
  99     void *ksa_restorer;
 100 };
 101
 102 /* Similar to the sigaction function in libc, except it leaves alone the
 103    restorer field, which is used to specify the signal stack address */
 104 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
 105                                   struct kernel_sigaction *old )
 106 {
 107     __asm__ __volatile__( "pushl %%ebx\n\t"
 108                           "movl %2,%%ebx\n\t"
 109                           "int $0x80\n\t"
 110                           "popl %%ebx"
 111                           : "=a" (sig)
 112                           : "0" (SYS_sigaction), "S" (sig), "c" (new), "d" (old) );
 113     if (sig>=0) return 0;
 114     errno = -sig;
 115     return -1;
 116 }
 117
 118 #ifdef HAVE_SIGALTSTACK
 119 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
 120 static inline int wine_sigaltstack( const struct sigaltstack *new,
 121                                     struct sigaltstack *old )
 122 {
 123     int ret;
 124     __asm__ __volatile__( "pushl %%ebx\n\t"
 125                           "movl %2,%%ebx\n\t"
 126                           "int $0x80\n\t"
 127                           "popl %%ebx"
 128                           : "=a" (ret)
 129                           : "0" (SYS_sigaltstack), "q" (new), "c" (old) );
 130     if (ret >= 0) return 0;
 131     errno = -ret;
 132     return -1;
 133 }
 134 #endif
 135
 136 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 137
 138 int vm86_enter( void **vm86_ptr );
 139 void vm86_return(void);
 140 void vm86_return_end(void);
 141 __ASM_GLOBAL_FUNC(vm86_enter,
 142                   "pushl %ebp\n\t"
 143                   "movl %esp, %ebp\n\t"
 144                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 145                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 146                   "movl (%ecx),%ecx\n\t"
 147                   "pushl %ebx\n\t"
 148                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 149                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 150                   "pushl %fs\n\t"
 151                   "pushl %gs\n\t"
 152                   "int $0x80\n"
 153                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 154                   __ASM_FUNC("vm86_return") "\n"
 155                   __ASM_NAME("vm86_return") ":\n\t"
 156                   "popl %gs\n\t"
 157                   "popl %fs\n\t"
 158                   "popl %ecx\n\t"
 159                   "popl %ebx\n\t"
 160                   "popl %ebp\n\t"
 161                   "testl %eax,%eax\n\t"
 162                   "jl 0f\n\t"
 163                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 164                   "je " __ASM_NAME("vm86_enter") "\n\t"
 165                   "0:\n\t"
 166                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 167                   "movl $0,(%ecx)\n\t"
 168                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 169                   __ASM_FUNC("vm86_return_end") "\n"
 170                   __ASM_NAME("vm86_return_end") ":\n\t"
 171                   "ret" );
 172
 173 #ifdef HAVE_SYS_VM86_H
 174 # define __HAVE_VM86
 175 #endif
 176
 177 #endif  /* linux */
 178
 179 #ifdef BSDI
 180
 181 #define EAX_sig(context)     ((context)->tf_eax)
 182 #define EBX_sig(context)     ((context)->tf_ebx)
 183 #define ECX_sig(context)     ((context)->tf_ecx)
 184 #define EDX_sig(context)     ((context)->tf_edx)
 185 #define ESI_sig(context)     ((context)->tf_esi)
 186 #define EDI_sig(context)     ((context)->tf_edi)
 187 #define EBP_sig(context)     ((context)->tf_ebp)
 188
 189 #define CS_sig(context)      ((context)->tf_cs)
 190 #define DS_sig(context)      ((context)->tf_ds)
 191 #define ES_sig(context)      ((context)->tf_es)
 192 #define SS_sig(context)      ((context)->tf_ss)
 193
 194 #include <machine/frame.h>
 195 typedef struct trapframe SIGCONTEXT;
 196
 197 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 198 #define HANDLER_CONTEXT __context
 199
 200 #define EFL_sig(context)     ((context)->tf_eflags)
 201
 202 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 203 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 204
 205 #endif /* bsdi */
 206
 207 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 208
 209 typedef struct sigcontext SIGCONTEXT;
 210
 211 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 212 #define HANDLER_CONTEXT __context
 213
 214 #endif  /* *BSD */
 215
 216 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 217
 218 #ifdef _SCO_DS
 219 #include <sys/regset.h>
 220 #endif
 221 /* Solaris kludge */
 222 #undef ERR
 223 #include <sys/ucontext.h>
 224 #undef ERR
 225 typedef struct ucontext SIGCONTEXT;
 226
 227 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 228 #define HANDLER_CONTEXT __context
 229
 230 #endif  /* svr4 || SCO_DS */
 231
 232 #ifdef __EMX__
 233
 234 typedef struct
 235 {
 236     unsigned long ContextFlags;
 237     FLOATING_SAVE_AREA sc_float;
 238     unsigned long sc_gs;
 239     unsigned long sc_fs;
 240     unsigned long sc_es;
 241     unsigned long sc_ds;
 242     unsigned long sc_edi;
 243     unsigned long sc_esi;
 244     unsigned long sc_eax;
 245     unsigned long sc_ebx;
 246     unsigned long sc_ecx;
 247     unsigned long sc_edx;
 248     unsigned long sc_ebp;
 249     unsigned long sc_eip;
 250     unsigned long sc_cs;
 251     unsigned long sc_eflags;
 252     unsigned long sc_esp;
 253     unsigned long sc_ss;
 254 } SIGCONTEXT;
 255
 256 #endif  /* __EMX__ */
 257
 258 #ifdef __CYGWIN__
 259
 260 /* FIXME: This section is just here so it can compile, it's most likely
 261  * completely wrong. */
 262
 263 typedef struct
 264 {
 265     unsigned short sc_gs, __gsh;
 266     unsigned short sc_fs, __fsh;
 267     unsigned short sc_es, __esh;
 268     unsigned short sc_ds, __dsh;
 269     unsigned long sc_edi;
 270     unsigned long sc_esi;
 271     unsigned long sc_ebp;
 272     unsigned long sc_esp;
 273     unsigned long sc_ebx;
 274     unsigned long sc_edx;
 275     unsigned long sc_ecx;
 276     unsigned long sc_eax;
 277     unsigned long sc_trapno;
 278     unsigned long sc_err;
 279     unsigned long sc_eip;
 280     unsigned short sc_cs, __csh;
 281     unsigned long sc_eflags;
 282     unsigned long esp_at_signal;
 283     unsigned short sc_ss, __ssh;
 284     unsigned long i387;
 285     unsigned long oldmask;
 286     unsigned long cr2;
 287 } SIGCONTEXT;
 288
 289 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
 290 #define HANDLER_CONTEXT (&__context)
 291
 292 #endif /* __CYGWIN__ */
 293
 294 #ifdef __APPLE__
 295 # include <sys/ucontext.h>
 296 # include <sys/types.h>
 297 # include <signal.h>
 298
 299 typedef ucontext_t SIGCONTEXT;
 300
 301 #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
 302 #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
 303 #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
 304 #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
 305 #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
 306 #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
 307 #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
 308
 309 #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
 310 #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
 311 #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
 312 #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
 313 #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
 314 #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
 315
 316 #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
 317
 318 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
 319 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
 320
 321 #define HANDLER_DEF(name) void name( int __signal, siginfo_t *__siginfo, SIGCONTEXT *__context )
 322 #define HANDLER_CONTEXT (__context)
 323
 324 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 325 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 326
 327 #define FAULT_ADDRESS        (__siginfo->si_addr)
 328
 329 #endif /* __APPLE__ */
 330
 331 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) ||\
 332     defined(__OpenBSD__) || defined(__EMX__) || defined(__CYGWIN__)
 333
 334 #define EAX_sig(context)     ((context)->sc_eax)
 335 #define EBX_sig(context)     ((context)->sc_ebx)
 336 #define ECX_sig(context)     ((context)->sc_ecx)
 337 #define EDX_sig(context)     ((context)->sc_edx)
 338 #define ESI_sig(context)     ((context)->sc_esi)
 339 #define EDI_sig(context)     ((context)->sc_edi)
 340 #define EBP_sig(context)     ((context)->sc_ebp)
 341
 342 #define CS_sig(context)      ((context)->sc_cs)
 343 #define DS_sig(context)      ((context)->sc_ds)
 344 #define ES_sig(context)      ((context)->sc_es)
 345 #define FS_sig(context)      ((context)->sc_fs)
 346 #define GS_sig(context)      ((context)->sc_gs)
 347 #define SS_sig(context)      ((context)->sc_ss)
 348
 349 #define TRAP_sig(context)    ((context)->sc_trapno)
 350
 351 #ifdef __NetBSD__
 352 #define ERROR_sig(context)   ((context)->sc_err)
 353 #endif
 354
 355 #ifdef linux
 356 #define ERROR_sig(context)   ((context)->sc_err)
 357 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 358 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->cr2)
 359 #endif
 360
 361 #ifdef __FreeBSD__
 362 #define EFL_sig(context)     ((context)->sc_efl)
 363 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 364 #define FAULT_ADDRESS        ((void *)HANDLER_CONTEXT->sc_err)
 365 #else
 366 #define EFL_sig(context)     ((context)->sc_eflags)
 367 #endif
 368
 369 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 370 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 371
 372 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 373
 374 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 375
 376 #ifdef _SCO_DS
 377 #define gregs regs
 378 #endif
 379
 380 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 381 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 382 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 383 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 384 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 385 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 386 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 387
 388 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 389 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 390 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 391 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 392
 393 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 394 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 395
 396 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 397
 398 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 399 #ifdef UESP
 400 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 401 #elif defined(R_ESP)
 402 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 403 #else
 404 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 405 #endif
 406 #ifdef TRAPNO
 407 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 408 #endif
 409
 410 #define FAULT_ADDRESS         (__siginfo->si_addr)
 411
 412 #endif  /* svr4 || SCO_DS */
 413
 414 /* exception code definitions (already defined by FreeBSD/NetBSD) */
 415 #if !defined(__FreeBSD__) && !defined(__NetBSD__) /* FIXME: other BSDs? */
 416 #define T_DIVIDE        0   /* Division by zero exception */
 417 #define T_TRCTRAP       1   /* Single-step exception */
 418 #define T_NMI           2   /* NMI interrupt */
 419 #define T_BPTFLT        3   /* Breakpoint exception */
 420 #define T_OFLOW         4   /* Overflow exception */
 421 #define T_BOUND         5   /* Bound range exception */
 422 #define T_PRIVINFLT     6   /* Invalid opcode exception */
 423 #define T_DNA           7   /* Device not available exception */
 424 #define T_DOUBLEFLT     8   /* Double fault exception */
 425 #define T_FPOPFLT       9   /* Coprocessor segment overrun */
 426 #define T_TSSFLT        10  /* Invalid TSS exception */
 427 #define T_SEGNPFLT      11  /* Segment not present exception */
 428 #define T_STKFLT        12  /* Stack fault */
 429 #define T_PROTFLT       13  /* General protection fault */
 430 #define T_PAGEFLT       14  /* Page fault */
 431 #define T_RESERVED      15  /* Unknown exception */
 432 #define T_ARITHTRAP     16  /* Floating point exception */
 433 #define T_ALIGNFLT      17  /* Alignment check exception */
 434 #define T_MCHK          18  /* Machine check exception */
 435 #define T_CACHEFLT      19  /* Cache flush exception */
 436 #endif
 437 #if defined(__NetBSD__)
 438 #define T_MCHK          19  /* Machine check exception */
 439 #endif
 440
 441 #define T_UNKNOWN     (-1)  /* Unknown fault (TRAP_sig not defined) */
 442
 443 #include "wine/exception.h"
 444 #include "wine/debug.h"
 445
 446 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 447
 448 typedef int (*wine_signal_handler)(unsigned int sig);
 449
 450 static size_t signal_stack_mask;
 451 static size_t signal_stack_size;
 452
 453 static wine_signal_handler handlers[256];
 454
 455 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( const CONTEXT *context );
 456
 457
 458 /***********************************************************************
 459  *           dispatch_signal
 460  */
 461 inline static int dispatch_signal(unsigned int sig)
 462 {
 463     if (handlers[sig] == NULL) return 0;
 464     return handlers[sig](sig);
 465 }
 466
 467
 468 /***********************************************************************
 469  *           get_trap_code
 470  *
 471  * Get the trap code for a signal.
 472  */
 473 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 474 {
 475 #ifdef TRAP_sig
 476     return TRAP_sig(sigcontext);
 477 #else
 478     return T_UNKNOWN;  /* unknown trap code */
 479 #endif
 480 }
 481
 482 /***********************************************************************
 483  *           get_error_code
 484  *
 485  * Get the error code for a signal.
 486  */
 487 static inline WORD get_error_code( const SIGCONTEXT *sigcontext )
 488 {
 489 #ifdef ERROR_sig
 490     return ERROR_sig(sigcontext);
 491 #else
 492     return 0;
 493 #endif
 494 }
 495
 496 /***********************************************************************
 497  *           get_signal_stack
 498  *
 499  * Get the base of the signal stack for the current thread.
 500  */
 501 static inline void *get_signal_stack(void)
 502 {
 503     return (char *)NtCurrentTeb() + 4096;
 504 }
 505
 506
 507 /***********************************************************************
 508  *           get_current_teb
 509  *
 510  * Get the current teb based on the stack pointer.
 511  */
 512 static inline TEB *get_current_teb(void)
 513 {
 514     unsigned long esp;
 515     __asm__("movl %%esp,%0" : "=g" (esp) );
 516     return (TEB *)(esp & ~signal_stack_mask);
 517 }
 518
 519
 520 #ifdef __HAVE_VM86
 521 /***********************************************************************
 522  *           save_vm86_context
 523  *
 524  * Set the register values from a vm86 structure.
 525  */
 526 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 527 {
 528     context->Eax    = vm86->regs.eax;
 529     context->Ebx    = vm86->regs.ebx;
 530     context->Ecx    = vm86->regs.ecx;
 531     context->Edx    = vm86->regs.edx;
 532     context->Esi    = vm86->regs.esi;
 533     context->Edi    = vm86->regs.edi;
 534     context->Esp    = vm86->regs.esp;
 535     context->Ebp    = vm86->regs.ebp;
 536     context->Eip    = vm86->regs.eip;
 537     context->SegCs  = vm86->regs.cs;
 538     context->SegDs  = vm86->regs.ds;
 539     context->SegEs  = vm86->regs.es;
 540     context->SegFs  = vm86->regs.fs;
 541     context->SegGs  = vm86->regs.gs;
 542     context->SegSs  = vm86->regs.ss;
 543     context->EFlags = vm86->regs.eflags;
 544 }
 545
 546
 547 /***********************************************************************
 548  *           restore_vm86_context
 549  *
 550  * Build a vm86 structure from the register values.
 551  */
 552 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 553 {
 554     vm86->regs.eax    = context->Eax;
 555     vm86->regs.ebx    = context->Ebx;
 556     vm86->regs.ecx    = context->Ecx;
 557     vm86->regs.edx    = context->Edx;
 558     vm86->regs.esi    = context->Esi;
 559     vm86->regs.edi    = context->Edi;
 560     vm86->regs.esp    = context->Esp;
 561     vm86->regs.ebp    = context->Ebp;
 562     vm86->regs.eip    = context->Eip;
 563     vm86->regs.cs     = context->SegCs;
 564     vm86->regs.ds     = context->SegDs;
 565     vm86->regs.es     = context->SegEs;
 566     vm86->regs.fs     = context->SegFs;
 567     vm86->regs.gs     = context->SegGs;
 568     vm86->regs.ss     = context->SegSs;
 569     vm86->regs.eflags = context->EFlags;
 570 }
 571
 572
 573 /**********************************************************************
 574  *              merge_vm86_pending_flags
 575  *
 576  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 577  * raises exception if there are pending events and VIF flag
 578  * has been turned on.
 579  *
 580  * Called from __wine_enter_vm86 because vm86_enter
 581  * doesn't check for pending events.
 582  *
 583  * Called from raise_vm86_sti_exception to check for
 584  * pending events in a signal safe way.
 585  */
 586 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 587 {
 588     BOOL check_pending = TRUE;
 589     struct vm86plus_struct *vm86 =
 590         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 591
 592     /*
 593      * In order to prevent a race when SIGUSR2 occurs while
 594      * we are returning from exception handler, pending events
 595      * will be rechecked after each raised exception.
 596      */
 597     while (check_pending && NtCurrentTeb()->vm86_pending)
 598     {
 599         check_pending = FALSE;
 600         ntdll_get_thread_data()->vm86_ptr = NULL;
 601
 602         /*
 603          * If VIF is set, throw exception.
 604          * Note that SIGUSR2 may turn VIF flag off so
 605          * VIF check must occur only when TEB.vm86_ptr is NULL.
 606          */
 607         if (vm86->regs.eflags & VIF_MASK)
 608         {
 609             CONTEXT vcontext;
 610             save_vm86_context( &vcontext, vm86 );
 611
 612             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 613             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 614             rec->ExceptionRecord  = NULL;
 615             rec->NumberParameters = 0;
 616             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 617
 618             vcontext.EFlags &= ~VIP_MASK;
 619             NtCurrentTeb()->vm86_pending = 0;
 620             __regs_RtlRaiseException( rec, &vcontext );
 621
 622             restore_vm86_context( &vcontext, vm86 );
 623             check_pending = TRUE;
 624         }
 625
 626         ntdll_get_thread_data()->vm86_ptr = vm86;
 627     }
 628
 629     /*
 630      * Merge VIP flags in a signal safe way. This requires
 631      * that the following operation compiles into atomic
 632      * instruction.
 633      */
 634     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 635 }
 636 #endif /* __HAVE_VM86 */
 637
 638
 639 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 640
 641
 642 /***********************************************************************
 643  *           init_handler
 644  *
 645  * Handler initialization when the full context is not needed.
 646  */
 647 inline static void *init_handler( const SIGCONTEXT *sigcontext, WORD *fs, WORD *gs )
 648 {
 649     void *stack = (void *)ESP_sig(sigcontext);
 650     TEB *teb = get_current_teb();
 651     struct ntdll_thread_data *thread_data = (struct ntdll_thread_data *)teb->SystemReserved2;
 652
 653     /* get %fs and %gs at time of the fault */
 654 #ifdef FS_sig
 655     *fs = LOWORD(FS_sig(sigcontext));
 656 #else
 657     *fs = wine_get_fs();
 658 #endif
 659 #ifdef GS_sig
 660     *gs = LOWORD(GS_sig(sigcontext));
 661 #else
 662     *gs = wine_get_gs();
 663 #endif
 664
 665     wine_set_fs( thread_data->teb_sel );
 666
 667     /* now restore a proper %gs for the fault handler */
 668     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 669         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 670     {
 671         /*
 672          * Win16 or DOS protected mode. Note that during switch
 673          * from 16-bit mode to linear mode, CS may be set to system
 674          * segment before FS is restored. Fortunately, in this case
 675          * SS is still non-system segment. This is why both CS and SS
 676          * are checked.
 677          */
 678         wine_set_gs( teb->gs_sel );
 679         stack = teb->WOW32Reserved;
 680     }
 681 #ifdef __HAVE_VM86
 682     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 683     {
 684         unsigned int *int_stack = stack;
 685         /* fetch the saved %gs from the stack */
 686         wine_set_gs( int_stack[0] );
 687     }
 688 #endif
 689     else  /* 32-bit mode */
 690     {
 691 #ifdef GS_sig
 692         wine_set_gs( GS_sig(sigcontext) );
 693 #endif
 694     }
 695     return stack;
 696 }
 697
 698
 699 /***********************************************************************
 700  *           save_fpu
 701  *
 702  * Set the FPU context from a sigcontext.
 703  */
 704 inline static void save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 705 {
 706     context->ContextFlags |= CONTEXT86_FLOATING_POINT;
 707 #ifdef FPU_sig
 708     if (FPU_sig(sigcontext))
 709     {
 710         context->FloatSave = *FPU_sig(sigcontext);
 711         return;
 712     }
 713 #endif  /* FPU_sig */
 714 #ifdef __GNUC__
 715     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 716 #endif  /* __GNUC__ */
 717 }
 718
 719
 720 /***********************************************************************
 721  *           restore_fpu
 722  *
 723  * Restore the FPU context to a sigcontext.
 724  */
 725 inline static void restore_fpu( CONTEXT *context )
 726 {
 727     /* reset the current interrupt status */
 728     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 729 #ifdef __GNUC__
 730     /* avoid nested exceptions */
 731     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 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     context->ContextFlags = CONTEXT_FULL;
 744     context->Eax          = EAX_sig(sigcontext);
 745     context->Ebx          = EBX_sig(sigcontext);
 746     context->Ecx          = ECX_sig(sigcontext);
 747     context->Edx          = EDX_sig(sigcontext);
 748     context->Esi          = ESI_sig(sigcontext);
 749     context->Edi          = EDI_sig(sigcontext);
 750     context->Ebp          = EBP_sig(sigcontext);
 751     context->EFlags       = EFL_sig(sigcontext);
 752     context->Eip          = EIP_sig(sigcontext);
 753     context->Esp          = ESP_sig(sigcontext);
 754     context->SegCs        = LOWORD(CS_sig(sigcontext));
 755     context->SegDs        = LOWORD(DS_sig(sigcontext));
 756     context->SegEs        = LOWORD(ES_sig(sigcontext));
 757     context->SegFs        = fs;
 758     context->SegGs        = gs;
 759     context->SegSs        = LOWORD(SS_sig(sigcontext));
 760 }
 761
 762
 763 /***********************************************************************
 764  *           restore_context
 765  *
 766  * Restore the signal info from the context.
 767  */
 768 inline static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 769 {
 770     EAX_sig(sigcontext) = context->Eax;
 771     EBX_sig(sigcontext) = context->Ebx;
 772     ECX_sig(sigcontext) = context->Ecx;
 773     EDX_sig(sigcontext) = context->Edx;
 774     ESI_sig(sigcontext) = context->Esi;
 775     EDI_sig(sigcontext) = context->Edi;
 776     EBP_sig(sigcontext) = context->Ebp;
 777     EFL_sig(sigcontext) = context->EFlags;
 778     EIP_sig(sigcontext) = context->Eip;
 779     ESP_sig(sigcontext) = context->Esp;
 780     CS_sig(sigcontext)  = context->SegCs;
 781     DS_sig(sigcontext)  = context->SegDs;
 782     ES_sig(sigcontext)  = context->SegEs;
 783     SS_sig(sigcontext)  = context->SegSs;
 784 #ifdef GS_sig
 785     GS_sig(sigcontext)  = context->SegGs;
 786 #else
 787     wine_set_gs( context->SegGs );
 788 #endif
 789 #ifdef FS_sig
 790     FS_sig(sigcontext)  = context->SegFs;
 791 #else
 792     wine_set_fs( context->SegFs );
 793 #endif
 794 }
 795
 796
 797 /***********************************************************************
 798  *           set_cpu_context
 799  *
 800  * Set the new CPU context.
 801  */
 802 inline static void DECLSPEC_NORETURN set_cpu_context( CONTEXT *context )
 803 {
 804     DWORD flags = context->ContextFlags & ~CONTEXT_i386;
 805
 806     if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
 807     __wine_call_from_32_restore_regs( context );
 808 }
 809
 810
 811 /***********************************************************************
 812  *           is_privileged_instr
 813  *
 814  * Check if the fault location is a privileged instruction.
 815  * Based on the instruction emulation code in dlls/kernel/instr.c.
 816  */
 817 static inline int is_privileged_instr( CONTEXT86 *context )
 818 {
 819     const BYTE *instr;
 820     unsigned int prefix_count = 0;
 821
 822     if (!wine_ldt_is_system( context->SegCs )) return 0;
 823     instr = (BYTE *)context->Eip;
 824
 825     for (;;) switch(*instr)
 826     {
 827     /* instruction prefixes */
 828     case 0x2e:  /* %cs: */
 829     case 0x36:  /* %ss: */
 830     case 0x3e:  /* %ds: */
 831     case 0x26:  /* %es: */
 832     case 0x64:  /* %fs: */
 833     case 0x65:  /* %gs: */
 834     case 0x66:  /* opcode size */
 835     case 0x67:  /* addr size */
 836     case 0xf0:  /* lock */
 837     case 0xf2:  /* repne */
 838     case 0xf3:  /* repe */
 839         if (++prefix_count >= 15) return 0;
 840         instr++;
 841         continue;
 842
 843     case 0x0f: /* extended instruction */
 844         switch(instr[1])
 845         {
 846         case 0x20: /* mov crX, reg */
 847         case 0x21: /* mov drX, reg */
 848         case 0x22: /* mov reg, crX */
 849         case 0x23: /* mov reg drX */
 850             return 1;
 851         }
 852         return 0;
 853     case 0x6c: /* insb (%dx) */
 854     case 0x6d: /* insl (%dx) */
 855     case 0x6e: /* outsb (%dx) */
 856     case 0x6f: /* outsl (%dx) */
 857     case 0xcd: /* int $xx */
 858     case 0xe4: /* inb al,XX */
 859     case 0xe5: /* in (e)ax,XX */
 860     case 0xe6: /* outb XX,al */
 861     case 0xe7: /* out XX,(e)ax */
 862     case 0xec: /* inb (%dx),%al */
 863     case 0xed: /* inl (%dx),%eax */
 864     case 0xee: /* outb %al,(%dx) */
 865     case 0xef: /* outl %eax,(%dx) */
 866     case 0xf4: /* hlt */
 867     case 0xfa: /* cli */
 868     case 0xfb: /* sti */
 869         return 1;
 870     default:
 871         return 0;
 872     }
 873 }
 874
 875
 876 /***********************************************************************
 877  *           setup_exception
 878  *
 879  * Setup a proper stack frame for the raise function, and modify the
 880  * sigcontext so that the return from the signal handler will call
 881  * the raise function.
 882  */
 883 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 884 {
 885     struct stack_layout
 886     {
 887         void             *ret_addr;      /* return address from raise_func */
 888         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 889         CONTEXT          *context_ptr;   /* second arg for raise_func */
 890         CONTEXT           context;
 891         EXCEPTION_RECORD  rec;
 892         DWORD             ebp;
 893         DWORD             eip;
 894     } *stack;
 895
 896     WORD fs, gs;
 897
 898     stack = init_handler( sigcontext, &fs, &gs );
 899
 900     /* stack sanity checks */
 901
 902     if ((char *)stack >= (char *)get_signal_stack() &&
 903         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
 904     {
 905         ERR( "nested exception on signal stack in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 906              GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 907              NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 908         server_abort_thread(1);
 909     }
 910
 911     if (stack - 1 > stack || /* check for overflow in subtraction */
 912         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
 913         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 914     {
 915         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
 916         if (diff < 4096)
 917         {
 918             ERR( "stack overflow %u bytes in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 919                  diff, GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 920                  NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 921             server_abort_thread(1);
 922         }
 923         else WARN( "exception outside of stack limits in thread %04lx eip %08lx esp %08lx stack %p-%p\n",
 924                    GetCurrentThreadId(), EIP_sig(sigcontext), ESP_sig(sigcontext),
 925                    NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
 926     }
 927
 928     stack--;  /* push the stack_layout structure */
 929     stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
 930     stack->rec_ptr      = &stack->rec;
 931     stack->context_ptr  = &stack->context;
 932
 933     stack->rec.ExceptionRecord  = NULL;
 934     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 935     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 936     stack->rec.NumberParameters = 0;
 937
 938     save_context( &stack->context, sigcontext, fs, gs );
 939
 940     /* now modify the sigcontext to return to the raise function */
 941     ESP_sig(sigcontext) = (DWORD)stack;
 942     EIP_sig(sigcontext) = (DWORD)func;
 943     EFL_sig(sigcontext) &= ~0x100;  /* clear single-step flag */
 944     CS_sig(sigcontext)  = wine_get_cs();
 945     DS_sig(sigcontext)  = wine_get_ds();
 946     ES_sig(sigcontext)  = wine_get_es();
 947     FS_sig(sigcontext)  = wine_get_fs();
 948     GS_sig(sigcontext)  = wine_get_gs();
 949     SS_sig(sigcontext)  = wine_get_ss();
 950
 951     return stack->rec_ptr;
 952 }
 953
 954
 955 /***********************************************************************
 956  *           get_exception_context
 957  *
 958  * Get a pointer to the context built by setup_exception.
 959  */
 960 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 961 {
 962     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 963 }
 964
 965
 966 /**********************************************************************
 967  *              get_fpu_code
 968  *
 969  * Get the FPU exception code from the FPU status.
 970  */
 971 static inline DWORD get_fpu_code( const CONTEXT *context )
 972 {
 973     DWORD status = context->FloatSave.StatusWord;
 974
 975     if (status & 0x01)  /* IE */
 976     {
 977         if (status & 0x40)  /* SF */
 978             return EXCEPTION_FLT_STACK_CHECK;
 979         else
 980             return EXCEPTION_FLT_INVALID_OPERATION;
 981     }
 982     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 983     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 984     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 985     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 986     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 987     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 988 }
 989
 990
 991 /**********************************************************************
 992  *              raise_segv_exception
 993  */
 994 static void WINAPI DECLSPEC_NORETURN raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
 995 {
 996     switch(rec->ExceptionCode)
 997     {
 998     case EXCEPTION_ACCESS_VIOLATION:
 999         if (rec->NumberParameters == 2)
1000             rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] );
1001         break;
1002     case EXCEPTION_DATATYPE_MISALIGNMENT:
1003         /* FIXME: pass through exception handler first? */
1004         if (context->EFlags & 0x00040000)
1005         {
1006             /* Disable AC flag, return */
1007             context->EFlags &= ~0x00040000;
1008             goto done;
1009         }
1010         break;
1011     }
1012     __regs_RtlRaiseException( rec, context );
1013 done:
1014     set_cpu_context( context );
1015 }
1016
1017
1018 /**********************************************************************
1019  *              raise_trap_exception
1020  */
1021 static void WINAPI DECLSPEC_NORETURN raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1022 {
1023     DWORD dr0, dr1, dr2, dr3, dr6, dr7;
1024
1025     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1026     {
1027         if (context->EFlags & 0x100)
1028         {
1029             context->EFlags &= ~0x100;  /* clear single-step flag */
1030         }
1031         else  /* hardware breakpoint, fetch the debug registers */
1032         {
1033             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1034             NtGetContextThread(GetCurrentThread(), context);
1035             /* do we really have a bp from a debug register ?
1036              * if not, then someone did a kill(SIGTRAP) on us, and we
1037              * shall return a breakpoint, not a single step exception
1038              */
1039             if (!(context->Dr6 & 0xf)) rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1040         }
1041     }
1042
1043     dr0 = context->Dr0;
1044     dr1 = context->Dr1;
1045     dr2 = context->Dr2;
1046     dr3 = context->Dr3;
1047     dr6 = context->Dr6;
1048     dr7 = context->Dr7;
1049
1050     __regs_RtlRaiseException( rec, context );
1051
1052     if (dr0 != context->Dr0 || dr1 != context->Dr1 || dr2 != context->Dr2 ||
1053         dr3 != context->Dr3 || dr6 != context->Dr6 || dr7 != context->Dr7)
1054     {
1055         /* the debug registers have changed, set the new values */
1056         context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1057         NtSetContextThread(GetCurrentThread(), context);
1058     }
1059     context->ContextFlags = CONTEXT_FULL;  /* restore flags */
1060     set_cpu_context( context );
1061 }
1062
1063
1064 /**********************************************************************
1065  *              raise_exception
1066  *
1067  * Generic raise function for exceptions that don't need special treatment.
1068  */
1069 static void WINAPI DECLSPEC_NORETURN raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1070 {
1071     __regs_RtlRaiseException( rec, context );
1072     set_cpu_context( context );
1073 }
1074
1075
1076 #ifdef __HAVE_VM86
1077 /**********************************************************************
1078  *              raise_vm86_sti_exception
1079  */
1080 static void WINAPI DECLSPEC_NORETURN raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1081 {
1082     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1083     NtCurrentTeb()->vm86_pending |= VIP_MASK;
1084
1085     if (ntdll_get_thread_data()->vm86_ptr)
1086     {
1087         if (((char*)context->Eip >= (char*)vm86_return) &&
1088             ((char*)context->Eip <= (char*)vm86_return_end) &&
1089             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1090             /* exiting from VM86, can't throw */
1091             goto done;
1092         }
1093         merge_vm86_pending_flags( rec );
1094     }
1095     else if (NtCurrentTeb()->dpmi_vif &&
1096              !wine_ldt_is_system(context->SegCs) &&
1097              !wine_ldt_is_system(context->SegSs))
1098     {
1099         /* Executing DPMI code and virtual interrupts are enabled. */
1100         NtCurrentTeb()->vm86_pending = 0;
1101         __regs_RtlRaiseException( rec, context );
1102     }
1103 done:
1104     set_cpu_context( context );
1105 }
1106
1107
1108 /**********************************************************************
1109  *              usr2_handler
1110  *
1111  * Handler for SIGUSR2.
1112  * We use it to signal that the running __wine_enter_vm86() should
1113  * immediately set VIP_MASK, causing pending events to be handled
1114  * as early as possible.
1115  */
1116 static HANDLER_DEF(usr2_handler)
1117 {
1118     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_vm86_sti_exception );
1119     rec->ExceptionCode = EXCEPTION_VM86_STI;
1120 }
1121 #endif /* __HAVE_VM86 */
1122
1123
1124 /**********************************************************************
1125  *              segv_handler
1126  *
1127  * Handler for SIGSEGV and related errors.
1128  */
1129 static HANDLER_DEF(segv_handler)
1130 {
1131     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_segv_exception );
1132
1133     switch(get_trap_code(HANDLER_CONTEXT))
1134     {
1135     case T_OFLOW:   /* Overflow exception */
1136         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1137         break;
1138     case T_BOUND:   /* Bound range exception */
1139         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1140         break;
1141     case T_PRIVINFLT:   /* Invalid opcode exception */
1142         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1143         break;
1144     case T_STKFLT:  /* Stack fault */
1145         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1146         break;
1147     case T_SEGNPFLT:  /* Segment not present exception */
1148     case T_PROTFLT:   /* General protection fault */
1149     case T_UNKNOWN:   /* Unknown fault code */
1150         if (!get_error_code(HANDLER_CONTEXT) && is_privileged_instr( get_exception_context(rec) ))
1151             rec->ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1152         else
1153         {
1154             WORD err = get_error_code(HANDLER_CONTEXT);
1155             rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1156             rec->NumberParameters = 2;
1157             rec->ExceptionInformation[0] = 0;
1158             /* if error contains a LDT selector, use that as fault address */
1159             rec->ExceptionInformation[1] = (err & 7) == 4 ? (err & ~7) : 0xffffffff;
1160         }
1161         break;
1162     case T_PAGEFLT:  /* Page fault */
1163         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1164 #ifdef FAULT_ADDRESS
1165         rec->NumberParameters = 2;
1166         rec->ExceptionInformation[0] = (get_error_code(HANDLER_CONTEXT) & 2) != 0;
1167         rec->ExceptionInformation[1] = (ULONG_PTR)FAULT_ADDRESS;
1168 #endif
1169         break;
1170     case T_ALIGNFLT:  /* Alignment check exception */
1171         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1172         break;
1173     default:
1174         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1175         /* fall through */
1176     case T_NMI:       /* NMI interrupt */
1177     case T_DNA:       /* Device not available exception */
1178     case T_DOUBLEFLT: /* Double fault exception */
1179     case T_TSSFLT:    /* Invalid TSS exception */
1180     case T_RESERVED:  /* Unknown exception */
1181     case T_MCHK:      /* Machine check exception */
1182 #ifdef T_CACHEFLT
1183     case T_CACHEFLT:  /* Cache flush exception */
1184 #endif
1185         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1186         break;
1187     }
1188 }
1189
1190
1191 /**********************************************************************
1192  *              trap_handler
1193  *
1194  * Handler for SIGTRAP.
1195  */
1196 static HANDLER_DEF(trap_handler)
1197 {
1198     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_trap_exception );
1199
1200     switch(get_trap_code(HANDLER_CONTEXT))
1201     {
1202     case T_TRCTRAP:  /* Single-step exception */
1203         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1204         break;
1205     case T_BPTFLT:   /* Breakpoint exception */
1206         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1207         /* fall through */
1208     default:
1209         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1210         break;
1211     }
1212 }
1213
1214
1215 /**********************************************************************
1216  *              fpe_handler
1217  *
1218  * Handler for SIGFPE.
1219  */
1220 static HANDLER_DEF(fpe_handler)
1221 {
1222     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1223     CONTEXT *context;
1224
1225     context = get_exception_context( rec );
1226     save_fpu( context, HANDLER_CONTEXT );
1227
1228     switch(get_trap_code(HANDLER_CONTEXT))
1229     {
1230     case T_DIVIDE:   /* Division by zero exception */
1231         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1232         break;
1233     case T_FPOPFLT:   /* Coprocessor segment overrun */
1234         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1235         break;
1236     case T_ARITHTRAP:  /* Floating point exception */
1237     case T_UNKNOWN:    /* Unknown fault code */
1238         rec->ExceptionCode = get_fpu_code( context );
1239         break;
1240     default:
1241         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
1242         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1243         break;
1244     }
1245 }
1246
1247
1248 /**********************************************************************
1249  *              int_handler
1250  *
1251  * Handler for SIGINT.
1252  *
1253  * FIXME: should not be calling external functions on the signal stack.
1254  */
1255 static HANDLER_DEF(int_handler)
1256 {
1257     WORD fs, gs;
1258     init_handler( HANDLER_CONTEXT, &fs, &gs );
1259     if (!dispatch_signal(SIGINT))
1260     {
1261         EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1262         rec->ExceptionCode = CONTROL_C_EXIT;
1263     }
1264 }
1265
1266 /**********************************************************************
1267  *              abrt_handler
1268  *
1269  * Handler for SIGABRT.
1270  */
1271 static HANDLER_DEF(abrt_handler)
1272 {
1273     EXCEPTION_RECORD *rec = setup_exception( HANDLER_CONTEXT, raise_exception );
1274     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1275     rec->ExceptionFlags = EH_NONCONTINUABLE;
1276 }
1277
1278
1279 /**********************************************************************
1280  *              term_handler
1281  *
1282  * Handler for SIGTERM.
1283  */
1284 static HANDLER_DEF(term_handler)
1285 {
1286     WORD fs, gs;
1287     init_handler( HANDLER_CONTEXT, &fs, &gs );
1288     server_abort_thread(0);
1289 }
1290
1291
1292 /**********************************************************************
1293  *              usr1_handler
1294  *
1295  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1296  */
1297 static HANDLER_DEF(usr1_handler)
1298 {
1299     WORD fs, gs;
1300     CONTEXT context;
1301
1302     init_handler( HANDLER_CONTEXT, &fs, &gs );
1303     save_context( &context, HANDLER_CONTEXT, fs, gs );
1304     wait_suspend( &context );
1305     restore_context( &context, HANDLER_CONTEXT );
1306 }
1307
1308
1309 /**********************************************************************
1310  *              get_signal_stack_total_size
1311  *
1312  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1313  * Must be a power of two.
1314  */
1315 size_t get_signal_stack_total_size(void)
1316 {
1317     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1318
1319     if (!signal_stack_size)
1320     {
1321         size_t size = 4096, min_size = teb_size + max( MINSIGSTKSZ, 4096 );
1322         /* find the first power of two not smaller than min_size */
1323         while (size < min_size) size *= 2;
1324         signal_stack_mask = size - 1;
1325         signal_stack_size = size - teb_size;
1326     }
1327     return signal_stack_size + teb_size;
1328 }
1329
1330
1331 /***********************************************************************
1332  *           set_handler
1333  *
1334  * Set a signal handler
1335  */
1336 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
1337 {
1338     struct sigaction sig_act;
1339
1340 #ifdef linux
1341     if (!have_sigaltstack)
1342     {
1343         struct kernel_sigaction sig_act;
1344         sig_act.ksa_handler = func;
1345         sig_act.ksa_flags   = SA_RESTART;
1346         sig_act.ksa_mask    = (1 << (SIGINT-1)) |
1347                               (1 << (SIGUSR1-1)) |
1348                               (1 << (SIGUSR2-1));
1349         /* point to the top of the signal stack */
1350         sig_act.ksa_restorer = (char *)get_signal_stack() + signal_stack_size;
1351         return wine_sigaction( sig, &sig_act, NULL );
1352     }
1353 #endif  /* linux */
1354     sig_act.sa_handler = func;
1355     sigemptyset( &sig_act.sa_mask );
1356     sigaddset( &sig_act.sa_mask, SIGINT );
1357     sigaddset( &sig_act.sa_mask, SIGUSR1 );
1358     sigaddset( &sig_act.sa_mask, SIGUSR2 );
1359
1360 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
1361     sig_act.sa_flags = SA_RESTART;
1362 #elif defined (__svr4__) || defined(_SCO_DS) || defined(__APPLE__)
1363     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1364 #else
1365     sig_act.sa_flags = 0;
1366 #endif
1367
1368 #ifdef SA_ONSTACK
1369     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
1370 #endif
1371     return sigaction( sig, &sig_act, NULL );
1372 }
1373
1374
1375 /***********************************************************************
1376  *           __wine_set_signal_handler   (NTDLL.@)
1377  */
1378 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1379 {
1380     if (sig > sizeof(handlers) / sizeof(handlers[0])) return -1;
1381     if (handlers[sig] != NULL) return -2;
1382     handlers[sig] = wsh;
1383     return 0;
1384 }
1385
1386
1387 /**********************************************************************
1388  *              SIGNAL_Init
1389  */
1390 BOOL SIGNAL_Init(void)
1391 {
1392     int have_sigaltstack = 0;
1393
1394 #ifdef HAVE_SIGALTSTACK
1395     struct sigaltstack ss;
1396     ss.ss_sp    = get_signal_stack();
1397     ss.ss_size  = signal_stack_size;
1398     ss.ss_flags = 0;
1399     if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1400 #ifdef linux
1401     /* sigaltstack may fail because the kernel is too old, or
1402        because glibc is brain-dead. In the latter case a
1403        direct system call should succeed. */
1404     else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
1405 #endif  /* linux */
1406 #endif  /* HAVE_SIGALTSTACK */
1407
1408     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
1409     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
1410     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1411     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1412     if (set_handler( SIGABRT, have_sigaltstack, (void (*)())abrt_handler ) == -1) goto error;
1413     if (set_handler( SIGTERM, have_sigaltstack, (void (*)())term_handler ) == -1) goto error;
1414     if (set_handler( SIGUSR1, have_sigaltstack, (void (*)())usr1_handler ) == -1) goto error;
1415 #ifdef SIGBUS
1416     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
1417 #endif
1418 #ifdef SIGTRAP
1419     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
1420 #endif
1421
1422 #ifdef __HAVE_VM86
1423     if (set_handler( SIGUSR2, have_sigaltstack, (void (*)())usr2_handler ) == -1) goto error;
1424 #endif
1425
1426     return TRUE;
1427
1428  error:
1429     perror("sigaction");
1430     return FALSE;
1431 }
1432
1433
1434 #ifdef __HAVE_VM86
1435 /**********************************************************************
1436  *              __wine_enter_vm86   (NTDLL.@)
1437  *
1438  * Enter vm86 mode with the specified register context.
1439  */
1440 void __wine_enter_vm86( CONTEXT *context )
1441 {
1442     EXCEPTION_RECORD rec;
1443     int res;
1444     struct vm86plus_struct vm86;
1445
1446     memset( &vm86, 0, sizeof(vm86) );
1447     for (;;)
1448     {
1449         restore_vm86_context( context, &vm86 );
1450
1451         ntdll_get_thread_data()->vm86_ptr = &vm86;
1452         merge_vm86_pending_flags( &rec );
1453
1454         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1455         if (res < 0)
1456         {
1457             errno = -res;
1458             return;
1459         }
1460
1461         save_vm86_context( context, &vm86 );
1462
1463         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1464         rec.ExceptionRecord  = NULL;
1465         rec.ExceptionAddress = (LPVOID)context->Eip;
1466         rec.NumberParameters = 0;
1467
1468         switch(VM86_TYPE(res))
1469         {
1470         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1471             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1472             raise_segv_exception( &rec, context );
1473             continue;
1474         case VM86_TRAP: /* return due to DOS-debugger request */
1475             switch(VM86_ARG(res))
1476             {
1477             case T_TRCTRAP:  /* Single-step exception, single step flag is cleared by raise_trap_exception */
1478                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1479                 break;
1480             case T_BPTFLT:   /* Breakpoint exception */
1481                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1482                 /* fall through */
1483             default:
1484                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1485                 break;
1486             }
1487             raise_trap_exception( &rec, context );
1488             continue;
1489         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1490             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1491             rec.NumberParameters = 1;
1492             rec.ExceptionInformation[0] = VM86_ARG(res);
1493             break;
1494         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1495             context->EFlags |= VIF_MASK;
1496             context->EFlags &= ~VIP_MASK;
1497             NtCurrentTeb()->vm86_pending = 0;
1498             rec.ExceptionCode = EXCEPTION_VM86_STI;
1499             break;
1500         case VM86_PICRETURN: /* return due to pending PIC request */
1501             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1502             break;
1503         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1504         default:
1505             ERR( "unhandled result from vm86 mode %x\n", res );
1506             continue;
1507         }
1508         __regs_RtlRaiseException( &rec, context );
1509     }
1510 }
1511
1512 #else /* __HAVE_VM86 */
1513 /**********************************************************************
1514  *              __wine_enter_vm86   (NTDLL.@)
1515  */
1516 void __wine_enter_vm86( CONTEXT *context )
1517 {
1518     MESSAGE("vm86 mode not supported on this platform\n");
1519 }
1520 #endif /* __HAVE_VM86 */
1521
1522 /**********************************************************************
1523  *              DbgBreakPoint   (NTDLL.@)
1524  */
1525 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
1526
1527 /**********************************************************************
1528  *              DbgUserBreakPoint   (NTDLL.@)
1529  */
1530 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
1531
1532
1533 /**********************************************************************
1534  *              EXC_CallHandler   (internal)
1535  *
1536  * Some exception handlers depend on EBP to have a fixed position relative to
1537  * the exception frame.
1538  * Shrinker depends on (*1) doing what it does,
1539  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1540  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1541  * function calling the handler having only 5 parameters (*4).
1542  */
1543 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1544 "       pushl   %ebp\n"
1545 "       movl    %esp, %ebp\n"
1546 "       subl    $4,%esp\n"
1547 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1548 "       pushl   24(%ebp)\n"
1549 "       pushl   20(%ebp)\n"
1550 "       pushl   16(%ebp)\n"
1551 "       pushl   12(%ebp)\n"
1552 "       pushl   8(%ebp)\n"
1553 "       call    " __ASM_NAME("call_exception_handler") "\n"
1554 "       leave\n"
1555 "       ret\n"
1556 );
1557 __ASM_GLOBAL_FUNC(call_exception_handler,
1558 "       pushl   %ebp\n"
1559 "       movl    %esp, %ebp\n"
1560 "       subl    $12,%esp\n"
1561 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1562 "       pushl   %edx\n"           /* handler be handled by... */
1563 "       .byte   0x64\n"
1564 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1565 "       .byte   0x64\n"
1566 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1567 "       pushl   20(%ebp)\n"
1568 "       pushl   16(%ebp)\n"
1569 "       pushl   12(%ebp)\n"
1570 "       pushl   8(%ebp)\n"
1571 "       movl    24(%ebp), %ecx\n" /* (*1) */
1572 "       call    *%ecx\n"          /* call handler. (*2) */
1573 "       .byte   0x64\n"
1574 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1575 "       .byte   0x64\n"
1576 "       popl    (0)\n"            /* exception frame. */
1577 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1578 "       popl    %ebp\n"
1579 "       ret     $20\n"            /* (*4) */
1580 );
1581 #endif  /* __i386__ */