dlls/ntdll/signal_i386.c

   1 /*
   2  * i386 signal handling routines
   3  *
   4  * Copyright 1999 Alexandre Julliard
   5  */
   6
   7 #ifdef __i386__
   8
   9 #include "config.h"
  10
  11 #include <errno.h>
  12 #include <signal.h>
  13 #include <stdlib.h>
  14 #include <stdio.h>
  15 #include <unistd.h>
  16
  17 #ifdef HAVE_SYS_PARAM_H
  18 # include <sys/param.h>
  19 #endif
  20 #ifdef HAVE_SYSCALL_H
  21 # include <syscall.h>
  22 #else
  23 # ifdef HAVE_SYS_SYSCALL_H
  24 #  include <sys/syscall.h>
  25 # endif
  26 #endif
  27
  28 #include "selectors.h"
  29
  30 /***********************************************************************
  31  * signal context platform-specific definitions
  32  */
  33
  34 #ifdef linux
  35 typedef struct
  36 {
  37     unsigned short sc_gs, __gsh;
  38     unsigned short sc_fs, __fsh;
  39     unsigned short sc_es, __esh;
  40     unsigned short sc_ds, __dsh;
  41     unsigned long sc_edi;
  42     unsigned long sc_esi;
  43     unsigned long sc_ebp;
  44     unsigned long sc_esp;
  45     unsigned long sc_ebx;
  46     unsigned long sc_edx;
  47     unsigned long sc_ecx;
  48     unsigned long sc_eax;
  49     unsigned long sc_trapno;
  50     unsigned long sc_err;
  51     unsigned long sc_eip;
  52     unsigned short sc_cs, __csh;
  53     unsigned long sc_eflags;
  54     unsigned long esp_at_signal;
  55     unsigned short sc_ss, __ssh;
  56     unsigned long i387;
  57     unsigned long oldmask;
  58     unsigned long cr2;
  59 } SIGCONTEXT;
  60
  61 #define HANDLER_DEF(name) void name( int __signal, SIGCONTEXT __context )
  62 #define HANDLER_CONTEXT (&__context)
  63
  64 /* this is the sigaction structure from the Linux 2.1.20 kernel.  */
  65 #undef sa_handler
  66 struct kernel_sigaction
  67 {
  68     void (*sa_handler)();
  69     unsigned long sa_mask;
  70     unsigned long sa_flags;
  71     void *sa_restorer;
  72 };
  73
  74 /* Similar to the sigaction function in libc, except it leaves alone the
  75    restorer field, which is used to specify the signal stack address */
  76 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
  77                                   struct kernel_sigaction *old )
  78 {
  79     __asm__ __volatile__( "pushl %%ebx\n\t"
  80                           "movl %2,%%ebx\n\t"
  81                           "int $0x80\n\t"
  82                           "popl %%ebx"
  83                           : "=a" (sig)
  84                           : "0" (SYS_sigaction), "r" (sig), "c" (new), "d" (old) );
  85     if (sig>=0) return 0;
  86     errno = -sig;
  87     return -1;
  88 }
  89
  90 #endif  /* linux */
  91
  92 #ifdef BSDI
  93
  94 #define EAX_sig(context)     ((context)->tf_eax)
  95 #define EBX_sig(context)     ((context)->tf_ebx)
  96 #define ECX_sig(context)     ((context)->tf_ecx)
  97 #define EDX_sig(context)     ((context)->tf_edx)
  98 #define ESI_sig(context)     ((context)->tf_esi)
  99 #define EDI_sig(context)     ((context)->tf_edi)
 100 #define EBP_sig(context)     ((context)->tf_ebp)
 101
 102 #define CS_sig(context)      ((context)->tf_cs)
 103 #define DS_sig(context)      ((context)->tf_ds)
 104 #define ES_sig(context)      ((context)->tf_es)
 105 #define SS_sig(context)      ((context)->tf_ss)
 106
 107 #include <machine/frame.h>
 108 typedef struct trapframe SIGCONTEXT;
 109
 110 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 111 #define HANDLER_CONTEXT __context
 112
 113 #define EFL_sig(context)     ((context)->tf_eflags)
 114
 115 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 116 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 117
 118 #endif /* bsdi */
 119
 120 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 121
 122 typedef struct sigcontext SIGCONTEXT;
 123
 124 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 125 #define HANDLER_CONTEXT __context
 126
 127 #endif  /* FreeBSD */
 128
 129 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 130
 131 #ifdef _SCO_DS
 132 #include <sys/regset.h>
 133 #endif
 134 /* Solaris kludge */
 135 #undef ERR
 136 #include <sys/ucontext.h>
 137 #undef ERR
 138 typedef struct ucontext SIGCONTEXT;
 139
 140 #define HANDLER_DEF(name) void name( int __signal, void *__siginfo, SIGCONTEXT *__context )
 141 #define HANDLER_CONTEXT __context
 142
 143 #endif  /* svr4 || SCO_DS */
 144
 145 #ifdef __EMX__
 146
 147 typedef struct
 148 {
 149     unsigned long ContextFlags;
 150     FLOATING_SAVE_AREA sc_float;
 151     unsigned long sc_gs;
 152     unsigned long sc_fs;
 153     unsigned long sc_es;
 154     unsigned long sc_ds;
 155     unsigned long sc_edi;
 156     unsigned long sc_esi;
 157     unsigned long sc_eax;
 158     unsigned long sc_ebx;
 159     unsigned long sc_ecx;
 160     unsigned long sc_edx;
 161     unsigned long sc_ebp;
 162     unsigned long sc_eip;
 163     unsigned long sc_cs;
 164     unsigned long sc_eflags;
 165     unsigned long sc_esp;
 166     unsigned long sc_ss;
 167 } SIGCONTEXT;
 168
 169 #endif  /* __EMX__ */
 170
 171
 172 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__EMX__)
 173
 174 #define EAX_sig(context)     ((context)->sc_eax)
 175 #define EBX_sig(context)     ((context)->sc_ebx)
 176 #define ECX_sig(context)     ((context)->sc_ecx)
 177 #define EDX_sig(context)     ((context)->sc_edx)
 178 #define ESI_sig(context)     ((context)->sc_esi)
 179 #define EDI_sig(context)     ((context)->sc_edi)
 180 #define EBP_sig(context)     ((context)->sc_ebp)
 181
 182 #define CS_sig(context)      ((context)->sc_cs)
 183 #define DS_sig(context)      ((context)->sc_ds)
 184 #define ES_sig(context)      ((context)->sc_es)
 185 #define SS_sig(context)      ((context)->sc_ss)
 186
 187 /* FS and GS are now in the sigcontext struct of FreeBSD, but not
 188  * saved by the exception handling. duh.
 189  * Actually they are in -current (have been for a while), and that
 190  * patch now finally has been MFC'd to -stable too (Nov 15 1999).
 191  * If you're running a system from the -stable branch older than that,
 192  * like a 3.3-RELEASE, grab the patch from the ports tree:
 193  * ftp://ftp.freebsd.org/pub/FreeBSD/FreeBSD-current/ports/emulators/wine/files/patch-3.3-sys-fsgs
 194  * (If its not yet there when you look, go here:
 195  * http://www.jelal.kn-bremen.de/freebsd/ports/emulators/wine/files/ )
 196  */
 197 #ifdef __FreeBSD__
 198 #define FS_sig(context)      ((context)->sc_fs)
 199 #define GS_sig(context)      ((context)->sc_gs)
 200 #endif
 201
 202 #ifdef linux
 203 #define FS_sig(context)      ((context)->sc_fs)
 204 #define GS_sig(context)      ((context)->sc_gs)
 205 #define CR2_sig(context)     ((context)->cr2)
 206 #define TRAP_sig(context)    ((context)->sc_trapno)
 207 #define ERROR_sig(context)   ((context)->sc_err)
 208 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 209 #endif
 210
 211 #ifndef __FreeBSD__
 212 #define EFL_sig(context)     ((context)->sc_eflags)
 213 #else
 214 #define EFL_sig(context)     ((context)->sc_efl)
 215 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 216 #define CR2_sig(context)     ((context)->sc_err)
 217 #define TRAP_sig(context)    ((context)->sc_trapno)
 218 #endif
 219
 220 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 221 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 222
 223 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 224
 225 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 226
 227 #ifdef _SCO_DS
 228 #define gregs regs
 229 #endif
 230
 231 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 232 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 233 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 234 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 235 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 236 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 237 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 238
 239 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 240 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 241 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 242 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 243
 244 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 245 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 246
 247 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 248
 249 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 250 #ifdef R_ESP
 251 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 252 #else
 253 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 254 #endif
 255 #ifdef TRAPNO
 256 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 257 #endif
 258
 259 #endif  /* svr4 || SCO_DS */
 260
 261
 262 /* exception code definitions (already defined by FreeBSD) */
 263 #ifndef __FreeBSD__  /* FIXME: other BSDs? */
 264 #define T_DIVIDE        0   /* Division by zero exception */
 265 #define T_TRCTRAP       1   /* Single-step exception */
 266 #define T_NMI           2   /* NMI interrupt */
 267 #define T_BPTFLT        3   /* Breakpoint exception */
 268 #define T_OFLOW         4   /* Overflow exception */
 269 #define T_BOUND         5   /* Bound range exception */
 270 #define T_PRIVINFLT     6   /* Invalid opcode exception */
 271 #define T_DNA           7   /* Device not available exception */
 272 #define T_DOUBLEFLT     8   /* Double fault exception */
 273 #define T_FPOPFLT       9   /* Coprocessor segment overrun */
 274 #define T_TSSFLT        10  /* Invalid TSS exception */
 275 #define T_SEGNPFLT      11  /* Segment not present exception */
 276 #define T_STKFLT        12  /* Stack fault */
 277 #define T_PROTFLT       13  /* General protection fault */
 278 #define T_PAGEFLT       14  /* Page fault */
 279 #define T_RESERVED      15  /* Unknown exception */
 280 #define T_ARITHTRAP     16  /* Floating point exception */
 281 #define T_ALIGNFLT      17  /* Alignment check exception */
 282 #define T_MCHK          18  /* Machine check exception */
 283 #define T_CACHEFLT      19  /* Cache flush exception */
 284 #endif
 285
 286 #define T_UNKNOWN     (-1)  /* Unknown fault (TRAP_sig not defined) */
 287
 288 #include "wine/exception.h"
 289 #include "winnt.h"
 290 #include "stackframe.h"
 291 #include "global.h"
 292 #include "miscemu.h"
 293 #include "ntddk.h"
 294 #include "syslevel.h"
 295 #include "debugtools.h"
 296
 297 DEFAULT_DEBUG_CHANNEL(seh)
 298
 299
 300
 301 /***********************************************************************
 302  *           handler_init
 303  *
 304  * Initialization code for a signal handler.
 305  * Restores the proper %fs value for the current thread.
 306  */
 307 static inline void handler_init( CONTEXT *context, const SIGCONTEXT *sigcontext )
 308 {
 309     WORD fs;
 310     /* get %fs at time of the fault */
 311 #ifdef FS_sig
 312     fs = FS_sig(sigcontext);
 313 #else
 314     fs = __get_fs();
 315 #endif
 316     context->SegFs = fs;
 317     /* now restore a proper %fs for the fault handler */
 318     if (!IS_SELECTOR_SYSTEM(CS_sig(sigcontext))) fs = SYSLEVEL_Win16CurrentTeb;
 319     if (!fs) fs = SYSLEVEL_EmergencyTeb;
 320     __set_fs(fs);
 321 }
 322
 323 /***********************************************************************
 324  *           get_trap_code
 325  *
 326  * Get the trap code for a signal.
 327  */
 328 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 329 {
 330 #ifdef TRAP_sig
 331     return TRAP_sig(sigcontext);
 332 #else
 333     return T_UNKNOWN;  /* unknown trap code */
 334 #endif
 335 }
 336
 337 /***********************************************************************
 338  *           save_context
 339  *
 340  * Set the register values from a sigcontext.
 341  */
 342 static void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext )
 343 {
 344     context->Eax    = EAX_sig(sigcontext);
 345     context->Ebx    = EBX_sig(sigcontext);
 346     context->Ecx    = ECX_sig(sigcontext);
 347     context->Edx    = EDX_sig(sigcontext);
 348     context->Esi    = ESI_sig(sigcontext);
 349     context->Edi    = EDI_sig(sigcontext);
 350     context->Ebp    = EBP_sig(sigcontext);
 351     context->EFlags = EFL_sig(sigcontext);
 352     context->Eip    = EIP_sig(sigcontext);
 353     context->Esp    = ESP_sig(sigcontext);
 354     context->SegCs  = LOWORD(CS_sig(sigcontext));
 355     context->SegDs  = LOWORD(DS_sig(sigcontext));
 356     context->SegEs  = LOWORD(ES_sig(sigcontext));
 357     context->SegSs  = LOWORD(SS_sig(sigcontext));
 358     /* %fs already handled in handler_init */
 359 #ifdef GS_sig
 360     context->SegGs  = LOWORD(GS_sig(sigcontext));
 361 #else
 362     context->SegGs  = __get_gs();
 363 #endif
 364     if (ISV86(context)) V86BASE(context) = (DWORD)DOSMEM_MemoryBase(0);
 365 }
 366
 367
 368 /***********************************************************************
 369  *           restore_context
 370  *
 371  * Build a sigcontext from the register values.
 372  */
 373 static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 374 {
 375     EAX_sig(sigcontext) = context->Eax;
 376     EBX_sig(sigcontext) = context->Ebx;
 377     ECX_sig(sigcontext) = context->Ecx;
 378     EDX_sig(sigcontext) = context->Edx;
 379     ESI_sig(sigcontext) = context->Esi;
 380     EDI_sig(sigcontext) = context->Edi;
 381     EBP_sig(sigcontext) = context->Ebp;
 382     EFL_sig(sigcontext) = context->EFlags;
 383     EIP_sig(sigcontext) = context->Eip;
 384     ESP_sig(sigcontext) = context->Esp;
 385     CS_sig(sigcontext)  = context->SegCs;
 386     DS_sig(sigcontext)  = context->SegDs;
 387     ES_sig(sigcontext)  = context->SegEs;
 388     SS_sig(sigcontext)  = context->SegSs;
 389 #ifdef FS_sig
 390     FS_sig(sigcontext)  = context->SegFs;
 391 #else
 392     __set_fs( context->SegFs );
 393 #endif
 394 #ifdef GS_sig
 395     GS_sig(sigcontext)  = context->SegGs;
 396 #else
 397     __set_gs( context->SegGs );
 398 #endif
 399 }
 400
 401
 402 /***********************************************************************
 403  *           save_fpu
 404  *
 405  * Set the FPU context from a sigcontext.
 406  */
 407 static void inline save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 408 {
 409 #ifdef FPU_sig
 410     if (FPU_sig(sigcontext))
 411     {
 412         context->FloatSave = *FPU_sig(sigcontext);
 413         return;
 414     }
 415 #endif  /* FPU_sig */
 416 #ifdef __GNUC__
 417     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 418 #endif  /* __GNUC__ */
 419 }
 420
 421
 422 /***********************************************************************
 423  *           restore_fpu
 424  *
 425  * Restore the FPU context to a sigcontext.
 426  */
 427 static void inline restore_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 428 {
 429 #ifdef FPU_sig
 430     if (FPU_sig(sigcontext))
 431     {
 432         *FPU_sig(sigcontext) = context->FloatSave;
 433         return;
 434     }
 435 #endif  /* FPU_sig */
 436 #ifdef __GNUC__
 437     /* avoid nested exceptions */
 438     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 439     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 440 #endif  /* __GNUC__ */
 441 }
 442
 443
 444 /**********************************************************************
 445  *              get_fpu_code
 446  *
 447  * Get the FPU exception code from the FPU status.
 448  */
 449 static inline DWORD get_fpu_code( const CONTEXT *context )
 450 {
 451     DWORD status = context->FloatSave.StatusWord;
 452
 453     if (status & 0x01)  /* IE */
 454     {
 455         if (status & 0x40)  /* SF */
 456             return EXCEPTION_FLT_STACK_CHECK;
 457         else
 458             return EXCEPTION_FLT_INVALID_OPERATION;
 459     }
 460     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 461     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 462     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 463     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 464     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 465     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 466 }
 467
 468
 469 /**********************************************************************
 470  *              segv_handler
 471  *
 472  * Handler for SIGSEGV and related errors.
 473  */
 474 static HANDLER_DEF(segv_handler)
 475 {
 476     EXCEPTION_RECORD rec;
 477     CONTEXT context;
 478
 479     handler_init( &context, HANDLER_CONTEXT );
 480
 481 #ifdef CR2_sig
 482     /* we want the page-fault case to be fast */
 483     if (get_trap_code(HANDLER_CONTEXT) == T_PAGEFLT)
 484         if (VIRTUAL_HandleFault( (LPVOID)CR2_sig(HANDLER_CONTEXT) )) return;
 485 #endif
 486
 487     save_context( &context, HANDLER_CONTEXT );
 488     rec.ExceptionRecord  = NULL;
 489     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 490     rec.ExceptionAddress = (LPVOID)context.Eip;
 491     rec.NumberParameters = 0;
 492
 493     switch(get_trap_code(HANDLER_CONTEXT))
 494     {
 495     case T_OFLOW:   /* Overflow exception */
 496         rec.ExceptionCode = EXCEPTION_INT_OVERFLOW;
 497         break;
 498     case T_BOUND:   /* Bound range exception */
 499         rec.ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
 500         break;
 501     case T_PRIVINFLT:   /* Invalid opcode exception */
 502         rec.ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
 503         break;
 504     case T_STKFLT:  /* Stack fault */
 505         rec.ExceptionCode = EXCEPTION_STACK_OVERFLOW;
 506         break;
 507     case T_SEGNPFLT:  /* Segment not present exception */
 508     case T_PROTFLT:   /* General protection fault */
 509     case T_UNKNOWN:   /* Unknown fault code */
 510         if (INSTR_EmulateInstruction( &context )) goto restore;
 511         rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
 512         break;
 513     case T_PAGEFLT:  /* Page fault */
 514 #ifdef CR2_sig
 515         rec.NumberParameters = 2;
 516 #ifdef ERROR_sig
 517         rec.ExceptionInformation[0] = (ERROR_sig(HANDLER_CONTEXT) & 2) != 0;
 518 #else
 519         rec.ExceptionInformation[0] = 0;
 520 #endif /* ERROR_sig */
 521         rec.ExceptionInformation[1] = CR2_sig(HANDLER_CONTEXT);
 522 #endif /* CR2_sig */
 523         rec.ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
 524         break;
 525     case T_ALIGNFLT:  /* Alignment check exception */
 526         /* FIXME: pass through exception handler first? */
 527         if (context.EFlags & 0x00040000)
 528         {
 529             /* Disable AC flag, return */
 530             context.EFlags &= ~0x00040000;
 531             goto restore;
 532         }
 533         rec.ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
 534         break;
 535     default:
 536         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
 537         /* fall through */
 538     case T_NMI:       /* NMI interrupt */
 539     case T_DNA:       /* Device not available exception */
 540     case T_DOUBLEFLT: /* Double fault exception */
 541     case T_TSSFLT:    /* Invalid TSS exception */
 542     case T_RESERVED:  /* Unknown exception */
 543     case T_MCHK:      /* Machine check exception */
 544 #ifdef T_CACHEFLT
 545     case T_CACHEFLT:  /* Cache flush exception */
 546 #endif
 547         rec.ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
 548         break;
 549     }
 550
 551     EXC_RtlRaiseException( &rec, &context );
 552  restore:
 553     restore_context( &context, HANDLER_CONTEXT );
 554 }
 555
 556
 557 /**********************************************************************
 558  *              trap_handler
 559  *
 560  * Handler for SIGTRAP.
 561  */
 562 static HANDLER_DEF(trap_handler)
 563 {
 564     EXCEPTION_RECORD rec;
 565     CONTEXT context;
 566
 567     handler_init( &context, HANDLER_CONTEXT );
 568
 569     save_context( &context, HANDLER_CONTEXT );
 570     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 571     rec.ExceptionRecord  = NULL;
 572     rec.ExceptionAddress = (LPVOID)context.Eip;
 573     rec.NumberParameters = 0;
 574
 575     switch(get_trap_code(HANDLER_CONTEXT))
 576     {
 577     case T_TRCTRAP:  /* Single-step exception */
 578         rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
 579         context.EFlags &= ~0x100;  /* clear single-step flag */
 580         break;
 581     case T_BPTFLT:   /* Breakpoint exception */
 582         rec.ExceptionAddress = (char *) rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
 583         /* fall through */
 584     default:
 585         rec.ExceptionCode = EXCEPTION_BREAKPOINT;
 586         break;
 587     }
 588     EXC_RtlRaiseException( &rec, &context );
 589     restore_context( &context, HANDLER_CONTEXT );
 590 }
 591
 592
 593 /**********************************************************************
 594  *              fpe_handler
 595  *
 596  * Handler for SIGFPE.
 597  */
 598 static HANDLER_DEF(fpe_handler)
 599 {
 600     EXCEPTION_RECORD rec;
 601     CONTEXT context;
 602
 603     handler_init( &context, HANDLER_CONTEXT );
 604
 605     save_fpu( &context, HANDLER_CONTEXT );
 606
 607     switch(get_trap_code(HANDLER_CONTEXT))
 608     {
 609     case T_DIVIDE:   /* Division by zero exception */
 610         rec.ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
 611         break;
 612     case T_FPOPFLT:   /* Coprocessor segment overrun */
 613         rec.ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
 614         break;
 615     case T_ARITHTRAP:  /* Floating point exception */
 616     case T_UNKNOWN:    /* Unknown fault code */
 617         rec.ExceptionCode = get_fpu_code( &context );
 618         break;
 619     default:
 620         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
 621         rec.ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
 622         break;
 623     }
 624     save_context( &context, HANDLER_CONTEXT );
 625     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 626     rec.ExceptionRecord  = NULL;
 627     rec.ExceptionAddress = (LPVOID)context.Eip;
 628     rec.NumberParameters = 0;
 629     EXC_RtlRaiseException( &rec, &context );
 630     restore_context( &context, HANDLER_CONTEXT );
 631     restore_fpu( &context, HANDLER_CONTEXT );
 632 }
 633
 634
 635 /**********************************************************************
 636  *              int_handler
 637  *
 638  * Handler for SIGINT.
 639  */
 640 static HANDLER_DEF(int_handler)
 641 {
 642     EXCEPTION_RECORD rec;
 643     CONTEXT context;
 644
 645     handler_init( &context, HANDLER_CONTEXT );
 646     save_context( &context, HANDLER_CONTEXT );
 647     rec.ExceptionCode    = CONTROL_C_EXIT;
 648     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 649     rec.ExceptionRecord  = NULL;
 650     rec.ExceptionAddress = (LPVOID)context.Eip;
 651     rec.NumberParameters = 0;
 652     EXC_RtlRaiseException( &rec, &context );
 653     restore_context( &context, HANDLER_CONTEXT );
 654 }
 655
 656
 657 /***********************************************************************
 658  *           set_handler
 659  *
 660  * Set a signal handler
 661  */
 662 static int set_handler( int sig, void (*func)() )
 663 {
 664 #ifdef linux
 665     struct kernel_sigaction sig_act;
 666     sig_act.sa_handler = func;
 667     sig_act.sa_flags   = SA_RESTART | SA_NOMASK;
 668     sig_act.sa_mask    = 0;
 669     /* point to the top of the stack */
 670     sig_act.sa_restorer = (char *)NtCurrentTeb()->signal_stack + SIGNAL_STACK_SIZE;
 671     return wine_sigaction( sig, &sig_act, NULL );
 672 #else  /* linux */
 673     struct sigaction sig_act;
 674     sig_act.sa_handler = func;
 675     sigemptyset( &sig_act.sa_mask );
 676
 677 # if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 678     sig_act.sa_flags = SA_ONSTACK;
 679 # elif defined (__svr4__) || defined(_SCO_DS)
 680     sig_act.sa_flags = SA_SIGINFO | SA_ONSTACK | SA_RESTART;
 681 # elif defined(__EMX__)
 682     sig_act.sa_flags = 0; /* FIXME: EMX has only SA_ACK and SA_SYSV */
 683 # else
 684     sig_act.sa_flags = 0;
 685 # endif
 686     return sigaction( sig, &sig_act, NULL );
 687 #endif  /* linux */
 688 }
 689
 690
 691 /**********************************************************************
 692  *              SIGNAL_Init
 693  */
 694 BOOL SIGNAL_Init(void)
 695 {
 696 #ifdef HAVE_WORKING_SIGALTSTACK
 697     struct sigaltstack ss;
 698     if ((ss.ss_sp = NtCurrentTeb()->signal_stack))
 699     {
 700         ss.ss_size  = SIGNAL_STACK_SIZE;
 701         ss.ss_flags = 0;
 702         if (sigaltstack(&ss, NULL) < 0)
 703         {
 704             perror("sigaltstack");
 705             /* fall through on error and try it differently */
 706         }
 707     }
 708 #endif  /* HAVE_SIGALTSTACK */
 709
 710     /* ignore SIGPIPE so that WINSOCK can get a EPIPE error instead  */
 711     signal( SIGPIPE, SIG_IGN );
 712     /* automatic child reaping to avoid zombies */
 713     signal( SIGCHLD, SIG_IGN );
 714
 715     if (set_handler( SIGINT,  (void (*)())int_handler ) == -1) goto error;
 716     if (set_handler( SIGFPE,  (void (*)())fpe_handler ) == -1) goto error;
 717     if (set_handler( SIGSEGV, (void (*)())segv_handler ) == -1) goto error;
 718     if (set_handler( SIGILL,  (void (*)())segv_handler ) == -1) goto error;
 719 #ifdef SIGBUS
 720     if (set_handler( SIGBUS,  (void (*)())segv_handler ) == -1) goto error;
 721 #endif
 722 #ifdef SIGTRAP
 723     if (set_handler( SIGTRAP, (void (*)())trap_handler ) == -1) goto error;
 724 #endif
 725     return TRUE;
 726
 727  error:
 728     perror("sigaction");
 729     return FALSE;
 730 }
 731
 732 /**********************************************************************
 733  *              DbgBreakPoint   (NTDLL)
 734  */
 735 void WINAPI DbgBreakPoint(void);
 736 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
 737
 738 /**********************************************************************
 739  *              DbgUserBreakPoint   (NTDLL)
 740  */
 741 void WINAPI DbgUserBreakPoint(void);
 742 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
 743
 744 #endif  /* __i386__ */