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 struct kernel_sigaction
  66 {
  67     void (*ksa_handler)();
  68     unsigned long ksa_mask;
  69     unsigned long ksa_flags;
  70     void *ksa_restorer;
  71 };
  72
  73 /* Similar to the sigaction function in libc, except it leaves alone the
  74    restorer field, which is used to specify the signal stack address */
  75 static inline int wine_sigaction( int sig, struct kernel_sigaction *new,
  76                                   struct kernel_sigaction *old )
  77 {
  78     __asm__ __volatile__( "pushl %%ebx\n\t"
  79                           "movl %2,%%ebx\n\t"
  80                           "int $0x80\n\t"
  81                           "popl %%ebx"
  82                           : "=a" (sig)
  83                           : "0" (SYS_sigaction), "r" (sig), "c" (new), "d" (old) );
  84     if (sig>=0) return 0;
  85     errno = -sig;
  86     return -1;
  87 }
  88
  89 #ifdef HAVE_SIGALTSTACK
  90 /* direct syscall for sigaltstack to work around glibc 2.0 brain-damage */
  91 static inline int wine_sigaltstack( const struct sigaltstack *new,
  92                                     struct sigaltstack *old )
  93 {
  94     int ret;
  95     __asm__ __volatile__( "pushl %%ebx\n\t"
  96                           "movl %2,%%ebx\n\t"
  97                           "int $0x80\n\t"
  98                           "popl %%ebx"
  99                           : "=a" (ret)
 100                           : "0" (SYS_sigaltstack), "r" (new), "c" (old) );
 101     if (ret >= 0) return 0;
 102     errno = -ret;
 103     return -1;
 104 }
 105 #endif
 106
 107 #endif  /* linux */
 108
 109 #ifdef BSDI
 110
 111 #define EAX_sig(context)     ((context)->tf_eax)
 112 #define EBX_sig(context)     ((context)->tf_ebx)
 113 #define ECX_sig(context)     ((context)->tf_ecx)
 114 #define EDX_sig(context)     ((context)->tf_edx)
 115 #define ESI_sig(context)     ((context)->tf_esi)
 116 #define EDI_sig(context)     ((context)->tf_edi)
 117 #define EBP_sig(context)     ((context)->tf_ebp)
 118
 119 #define CS_sig(context)      ((context)->tf_cs)
 120 #define DS_sig(context)      ((context)->tf_ds)
 121 #define ES_sig(context)      ((context)->tf_es)
 122 #define SS_sig(context)      ((context)->tf_ss)
 123
 124 #include <machine/frame.h>
 125 typedef struct trapframe SIGCONTEXT;
 126
 127 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 128 #define HANDLER_CONTEXT __context
 129
 130 #define EFL_sig(context)     ((context)->tf_eflags)
 131
 132 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 133 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 134
 135 #endif /* bsdi */
 136
 137 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
 138
 139 typedef struct sigcontext SIGCONTEXT;
 140
 141 #define HANDLER_DEF(name) void name( int __signal, int code, SIGCONTEXT *__context )
 142 #define HANDLER_CONTEXT __context
 143
 144 #endif  /* FreeBSD */
 145
 146 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 147
 148 #ifdef _SCO_DS
 149 #include <sys/regset.h>
 150 #endif
 151 /* Solaris kludge */
 152 #undef ERR
 153 #include <sys/ucontext.h>
 154 #undef ERR
 155 typedef struct ucontext SIGCONTEXT;
 156
 157 #define HANDLER_DEF(name) void name( int __signal, void *__siginfo, SIGCONTEXT *__context )
 158 #define HANDLER_CONTEXT __context
 159
 160 #endif  /* svr4 || SCO_DS */
 161
 162 #ifdef __EMX__
 163
 164 typedef struct
 165 {
 166     unsigned long ContextFlags;
 167     FLOATING_SAVE_AREA sc_float;
 168     unsigned long sc_gs;
 169     unsigned long sc_fs;
 170     unsigned long sc_es;
 171     unsigned long sc_ds;
 172     unsigned long sc_edi;
 173     unsigned long sc_esi;
 174     unsigned long sc_eax;
 175     unsigned long sc_ebx;
 176     unsigned long sc_ecx;
 177     unsigned long sc_edx;
 178     unsigned long sc_ebp;
 179     unsigned long sc_eip;
 180     unsigned long sc_cs;
 181     unsigned long sc_eflags;
 182     unsigned long sc_esp;
 183     unsigned long sc_ss;
 184 } SIGCONTEXT;
 185
 186 #endif  /* __EMX__ */
 187
 188
 189 #if defined(linux) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__EMX__)
 190
 191 #define EAX_sig(context)     ((context)->sc_eax)
 192 #define EBX_sig(context)     ((context)->sc_ebx)
 193 #define ECX_sig(context)     ((context)->sc_ecx)
 194 #define EDX_sig(context)     ((context)->sc_edx)
 195 #define ESI_sig(context)     ((context)->sc_esi)
 196 #define EDI_sig(context)     ((context)->sc_edi)
 197 #define EBP_sig(context)     ((context)->sc_ebp)
 198
 199 #define CS_sig(context)      ((context)->sc_cs)
 200 #define DS_sig(context)      ((context)->sc_ds)
 201 #define ES_sig(context)      ((context)->sc_es)
 202 #define SS_sig(context)      ((context)->sc_ss)
 203
 204 /* FS and GS are now in the sigcontext struct of FreeBSD, but not
 205  * saved by the exception handling. duh.
 206  * Actually they are in -current (have been for a while), and that
 207  * patch now finally has been MFC'd to -stable too (Nov 15 1999).
 208  * If you're running a system from the -stable branch older than that,
 209  * like a 3.3-RELEASE, grab the patch from the ports tree:
 210  * ftp://ftp.freebsd.org/pub/FreeBSD/FreeBSD-current/ports/emulators/wine/files/patch-3.3-sys-fsgs
 211  * (If its not yet there when you look, go here:
 212  * http://www.jelal.kn-bremen.de/freebsd/ports/emulators/wine/files/ )
 213  */
 214 #ifdef __FreeBSD__
 215 #define FS_sig(context)      ((context)->sc_fs)
 216 #define GS_sig(context)      ((context)->sc_gs)
 217 #endif
 218
 219 #ifdef linux
 220 #define FS_sig(context)      ((context)->sc_fs)
 221 #define GS_sig(context)      ((context)->sc_gs)
 222 #define CR2_sig(context)     ((context)->cr2)
 223 #define TRAP_sig(context)    ((context)->sc_trapno)
 224 #define ERROR_sig(context)   ((context)->sc_err)
 225 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->i387))
 226 #endif
 227
 228 #ifndef __FreeBSD__
 229 #define EFL_sig(context)     ((context)->sc_eflags)
 230 #else
 231 #define EFL_sig(context)     ((context)->sc_efl)
 232 /* FreeBSD, see i386/i386/traps.c::trap_pfault va->err kludge  */
 233 #define CR2_sig(context)     ((context)->sc_err)
 234 #define TRAP_sig(context)    ((context)->sc_trapno)
 235 #endif
 236
 237 #define EIP_sig(context)     (*((unsigned long*)&(context)->sc_eip))
 238 #define ESP_sig(context)     (*((unsigned long*)&(context)->sc_esp))
 239
 240 #endif  /* linux || __NetBSD__ || __FreeBSD__ || __OpenBSD__ */
 241
 242 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 243
 244 #ifdef _SCO_DS
 245 #define gregs regs
 246 #endif
 247
 248 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 249 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 250 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 251 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 252 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 253 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 254 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 255
 256 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 257 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 258 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 259 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 260
 261 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 262 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 263
 264 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 265
 266 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 267 #ifdef R_ESP
 268 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 269 #else
 270 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 271 #endif
 272 #ifdef TRAPNO
 273 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 274 #endif
 275
 276 #endif  /* svr4 || SCO_DS */
 277
 278
 279 /* exception code definitions (already defined by FreeBSD) */
 280 #ifndef __FreeBSD__  /* FIXME: other BSDs? */
 281 #define T_DIVIDE        0   /* Division by zero exception */
 282 #define T_TRCTRAP       1   /* Single-step exception */
 283 #define T_NMI           2   /* NMI interrupt */
 284 #define T_BPTFLT        3   /* Breakpoint exception */
 285 #define T_OFLOW         4   /* Overflow exception */
 286 #define T_BOUND         5   /* Bound range exception */
 287 #define T_PRIVINFLT     6   /* Invalid opcode exception */
 288 #define T_DNA           7   /* Device not available exception */
 289 #define T_DOUBLEFLT     8   /* Double fault exception */
 290 #define T_FPOPFLT       9   /* Coprocessor segment overrun */
 291 #define T_TSSFLT        10  /* Invalid TSS exception */
 292 #define T_SEGNPFLT      11  /* Segment not present exception */
 293 #define T_STKFLT        12  /* Stack fault */
 294 #define T_PROTFLT       13  /* General protection fault */
 295 #define T_PAGEFLT       14  /* Page fault */
 296 #define T_RESERVED      15  /* Unknown exception */
 297 #define T_ARITHTRAP     16  /* Floating point exception */
 298 #define T_ALIGNFLT      17  /* Alignment check exception */
 299 #define T_MCHK          18  /* Machine check exception */
 300 #define T_CACHEFLT      19  /* Cache flush exception */
 301 #endif
 302
 303 #define T_UNKNOWN     (-1)  /* Unknown fault (TRAP_sig not defined) */
 304
 305 #include "wine/exception.h"
 306 #include "winnt.h"
 307 #include "stackframe.h"
 308 #include "global.h"
 309 #include "miscemu.h"
 310 #include "ntddk.h"
 311 #include "syslevel.h"
 312 #include "debugtools.h"
 313
 314 DEFAULT_DEBUG_CHANNEL(seh)
 315
 316
 317
 318 /***********************************************************************
 319  *           handler_init
 320  *
 321  * Initialization code for a signal handler.
 322  * Restores the proper %fs value for the current thread.
 323  */
 324 static inline void handler_init( CONTEXT *context, const SIGCONTEXT *sigcontext )
 325 {
 326     WORD fs;
 327     /* get %fs at time of the fault */
 328 #ifdef FS_sig
 329     fs = FS_sig(sigcontext);
 330 #else
 331     fs = __get_fs();
 332 #endif
 333     context->SegFs = fs;
 334     /* now restore a proper %fs for the fault handler */
 335     if (!IS_SELECTOR_SYSTEM(CS_sig(sigcontext))) fs = SYSLEVEL_Win16CurrentTeb;
 336     if (!fs) fs = SYSLEVEL_EmergencyTeb;
 337     __set_fs(fs);
 338 }
 339
 340 /***********************************************************************
 341  *           get_trap_code
 342  *
 343  * Get the trap code for a signal.
 344  */
 345 static inline int get_trap_code( const SIGCONTEXT *sigcontext )
 346 {
 347 #ifdef TRAP_sig
 348     return TRAP_sig(sigcontext);
 349 #else
 350     return T_UNKNOWN;  /* unknown trap code */
 351 #endif
 352 }
 353
 354 /***********************************************************************
 355  *           save_context
 356  *
 357  * Set the register values from a sigcontext.
 358  */
 359 static void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext )
 360 {
 361     context->Eax    = EAX_sig(sigcontext);
 362     context->Ebx    = EBX_sig(sigcontext);
 363     context->Ecx    = ECX_sig(sigcontext);
 364     context->Edx    = EDX_sig(sigcontext);
 365     context->Esi    = ESI_sig(sigcontext);
 366     context->Edi    = EDI_sig(sigcontext);
 367     context->Ebp    = EBP_sig(sigcontext);
 368     context->EFlags = EFL_sig(sigcontext);
 369     context->Eip    = EIP_sig(sigcontext);
 370     context->Esp    = ESP_sig(sigcontext);
 371     context->SegCs  = LOWORD(CS_sig(sigcontext));
 372     context->SegDs  = LOWORD(DS_sig(sigcontext));
 373     context->SegEs  = LOWORD(ES_sig(sigcontext));
 374     context->SegSs  = LOWORD(SS_sig(sigcontext));
 375     /* %fs already handled in handler_init */
 376 #ifdef GS_sig
 377     context->SegGs  = LOWORD(GS_sig(sigcontext));
 378 #else
 379     context->SegGs  = __get_gs();
 380 #endif
 381     if (ISV86(context)) V86BASE(context) = (DWORD)DOSMEM_MemoryBase(0);
 382 }
 383
 384
 385 /***********************************************************************
 386  *           restore_context
 387  *
 388  * Build a sigcontext from the register values.
 389  */
 390 static void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 391 {
 392     EAX_sig(sigcontext) = context->Eax;
 393     EBX_sig(sigcontext) = context->Ebx;
 394     ECX_sig(sigcontext) = context->Ecx;
 395     EDX_sig(sigcontext) = context->Edx;
 396     ESI_sig(sigcontext) = context->Esi;
 397     EDI_sig(sigcontext) = context->Edi;
 398     EBP_sig(sigcontext) = context->Ebp;
 399     EFL_sig(sigcontext) = context->EFlags;
 400     EIP_sig(sigcontext) = context->Eip;
 401     ESP_sig(sigcontext) = context->Esp;
 402     CS_sig(sigcontext)  = context->SegCs;
 403     DS_sig(sigcontext)  = context->SegDs;
 404     ES_sig(sigcontext)  = context->SegEs;
 405     SS_sig(sigcontext)  = context->SegSs;
 406 #ifdef FS_sig
 407     FS_sig(sigcontext)  = context->SegFs;
 408 #else
 409     __set_fs( context->SegFs );
 410 #endif
 411 #ifdef GS_sig
 412     GS_sig(sigcontext)  = context->SegGs;
 413 #else
 414     __set_gs( context->SegGs );
 415 #endif
 416 }
 417
 418
 419 /***********************************************************************
 420  *           save_fpu
 421  *
 422  * Set the FPU context from a sigcontext.
 423  */
 424 static void inline save_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 425 {
 426 #ifdef FPU_sig
 427     if (FPU_sig(sigcontext))
 428     {
 429         context->FloatSave = *FPU_sig(sigcontext);
 430         return;
 431     }
 432 #endif  /* FPU_sig */
 433 #ifdef __GNUC__
 434     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 435 #endif  /* __GNUC__ */
 436 }
 437
 438
 439 /***********************************************************************
 440  *           restore_fpu
 441  *
 442  * Restore the FPU context to a sigcontext.
 443  */
 444 static void inline restore_fpu( CONTEXT *context, const SIGCONTEXT *sigcontext )
 445 {
 446 #ifdef FPU_sig
 447     if (FPU_sig(sigcontext))
 448     {
 449         *FPU_sig(sigcontext) = context->FloatSave;
 450         return;
 451     }
 452 #endif  /* FPU_sig */
 453 #ifdef __GNUC__
 454     /* avoid nested exceptions */
 455     context->FloatSave.StatusWord &= context->FloatSave.ControlWord | 0xffffff80;
 456     __asm__ __volatile__( "frstor %0; fwait" : : "m" (context->FloatSave) );
 457 #endif  /* __GNUC__ */
 458 }
 459
 460
 461 /**********************************************************************
 462  *              get_fpu_code
 463  *
 464  * Get the FPU exception code from the FPU status.
 465  */
 466 static inline DWORD get_fpu_code( const CONTEXT *context )
 467 {
 468     DWORD status = context->FloatSave.StatusWord;
 469
 470     if (status & 0x01)  /* IE */
 471     {
 472         if (status & 0x40)  /* SF */
 473             return EXCEPTION_FLT_STACK_CHECK;
 474         else
 475             return EXCEPTION_FLT_INVALID_OPERATION;
 476     }
 477     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 478     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 479     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 480     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
 481     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
 482     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
 483 }
 484
 485
 486 /**********************************************************************
 487  *              segv_handler
 488  *
 489  * Handler for SIGSEGV and related errors.
 490  */
 491 static HANDLER_DEF(segv_handler)
 492 {
 493     EXCEPTION_RECORD rec;
 494     CONTEXT context;
 495     DWORD page_fault_code = EXCEPTION_ACCESS_VIOLATION;
 496
 497     handler_init( &context, HANDLER_CONTEXT );
 498
 499 #ifdef CR2_sig
 500     /* we want the page-fault case to be fast */
 501     if (get_trap_code(HANDLER_CONTEXT) == T_PAGEFLT)
 502         if (!(page_fault_code = VIRTUAL_HandleFault( (LPVOID)CR2_sig(HANDLER_CONTEXT) ))) return;
 503 #endif
 504
 505     save_context( &context, HANDLER_CONTEXT );
 506     rec.ExceptionRecord  = NULL;
 507     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 508     rec.ExceptionAddress = (LPVOID)context.Eip;
 509     rec.NumberParameters = 0;
 510
 511     switch(get_trap_code(HANDLER_CONTEXT))
 512     {
 513     case T_OFLOW:   /* Overflow exception */
 514         rec.ExceptionCode = EXCEPTION_INT_OVERFLOW;
 515         break;
 516     case T_BOUND:   /* Bound range exception */
 517         rec.ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
 518         break;
 519     case T_PRIVINFLT:   /* Invalid opcode exception */
 520         rec.ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
 521         break;
 522     case T_STKFLT:  /* Stack fault */
 523         rec.ExceptionCode = EXCEPTION_STACK_OVERFLOW;
 524         break;
 525     case T_SEGNPFLT:  /* Segment not present exception */
 526     case T_PROTFLT:   /* General protection fault */
 527     case T_UNKNOWN:   /* Unknown fault code */
 528         if (INSTR_EmulateInstruction( &context )) goto restore;
 529         rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
 530         break;
 531     case T_PAGEFLT:  /* Page fault */
 532 #ifdef CR2_sig
 533         rec.NumberParameters = 2;
 534 #ifdef ERROR_sig
 535         rec.ExceptionInformation[0] = (ERROR_sig(HANDLER_CONTEXT) & 2) != 0;
 536 #else
 537         rec.ExceptionInformation[0] = 0;
 538 #endif /* ERROR_sig */
 539         rec.ExceptionInformation[1] = CR2_sig(HANDLER_CONTEXT);
 540 #endif /* CR2_sig */
 541         rec.ExceptionCode = page_fault_code;
 542         break;
 543     case T_ALIGNFLT:  /* Alignment check exception */
 544         /* FIXME: pass through exception handler first? */
 545         if (context.EFlags & 0x00040000)
 546         {
 547             /* Disable AC flag, return */
 548             context.EFlags &= ~0x00040000;
 549             goto restore;
 550         }
 551         rec.ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
 552         break;
 553     default:
 554         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
 555         /* fall through */
 556     case T_NMI:       /* NMI interrupt */
 557     case T_DNA:       /* Device not available exception */
 558     case T_DOUBLEFLT: /* Double fault exception */
 559     case T_TSSFLT:    /* Invalid TSS exception */
 560     case T_RESERVED:  /* Unknown exception */
 561     case T_MCHK:      /* Machine check exception */
 562 #ifdef T_CACHEFLT
 563     case T_CACHEFLT:  /* Cache flush exception */
 564 #endif
 565         rec.ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
 566         break;
 567     }
 568
 569     EXC_RtlRaiseException( &rec, &context );
 570  restore:
 571     restore_context( &context, HANDLER_CONTEXT );
 572 }
 573
 574
 575 /**********************************************************************
 576  *              trap_handler
 577  *
 578  * Handler for SIGTRAP.
 579  */
 580 static HANDLER_DEF(trap_handler)
 581 {
 582     EXCEPTION_RECORD rec;
 583     CONTEXT context;
 584
 585     handler_init( &context, HANDLER_CONTEXT );
 586
 587     save_context( &context, HANDLER_CONTEXT );
 588     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 589     rec.ExceptionRecord  = NULL;
 590     rec.ExceptionAddress = (LPVOID)context.Eip;
 591     rec.NumberParameters = 0;
 592
 593     switch(get_trap_code(HANDLER_CONTEXT))
 594     {
 595     case T_TRCTRAP:  /* Single-step exception */
 596         rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
 597         context.EFlags &= ~0x100;  /* clear single-step flag */
 598         break;
 599     case T_BPTFLT:   /* Breakpoint exception */
 600         rec.ExceptionAddress = (char *) rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
 601         /* fall through */
 602     default:
 603         rec.ExceptionCode = EXCEPTION_BREAKPOINT;
 604         break;
 605     }
 606     EXC_RtlRaiseException( &rec, &context );
 607     restore_context( &context, HANDLER_CONTEXT );
 608 }
 609
 610
 611 /**********************************************************************
 612  *              fpe_handler
 613  *
 614  * Handler for SIGFPE.
 615  */
 616 static HANDLER_DEF(fpe_handler)
 617 {
 618     EXCEPTION_RECORD rec;
 619     CONTEXT context;
 620
 621     handler_init( &context, HANDLER_CONTEXT );
 622
 623     save_fpu( &context, HANDLER_CONTEXT );
 624
 625     switch(get_trap_code(HANDLER_CONTEXT))
 626     {
 627     case T_DIVIDE:   /* Division by zero exception */
 628         rec.ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
 629         break;
 630     case T_FPOPFLT:   /* Coprocessor segment overrun */
 631         rec.ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
 632         break;
 633     case T_ARITHTRAP:  /* Floating point exception */
 634     case T_UNKNOWN:    /* Unknown fault code */
 635         rec.ExceptionCode = get_fpu_code( &context );
 636         break;
 637     default:
 638         ERR( "Got unexpected trap %d\n", get_trap_code(HANDLER_CONTEXT) );
 639         rec.ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
 640         break;
 641     }
 642     save_context( &context, HANDLER_CONTEXT );
 643     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 644     rec.ExceptionRecord  = NULL;
 645     rec.ExceptionAddress = (LPVOID)context.Eip;
 646     rec.NumberParameters = 0;
 647     EXC_RtlRaiseException( &rec, &context );
 648     restore_context( &context, HANDLER_CONTEXT );
 649     restore_fpu( &context, HANDLER_CONTEXT );
 650 }
 651
 652
 653 /**********************************************************************
 654  *              int_handler
 655  *
 656  * Handler for SIGINT.
 657  */
 658 static HANDLER_DEF(int_handler)
 659 {
 660     EXCEPTION_RECORD rec;
 661     CONTEXT context;
 662
 663     handler_init( &context, HANDLER_CONTEXT );
 664     save_context( &context, HANDLER_CONTEXT );
 665     rec.ExceptionCode    = CONTROL_C_EXIT;
 666     rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 667     rec.ExceptionRecord  = NULL;
 668     rec.ExceptionAddress = (LPVOID)context.Eip;
 669     rec.NumberParameters = 0;
 670     EXC_RtlRaiseException( &rec, &context );
 671     restore_context( &context, HANDLER_CONTEXT );
 672 }
 673
 674
 675 /***********************************************************************
 676  *           set_handler
 677  *
 678  * Set a signal handler
 679  */
 680 static int set_handler( int sig, int have_sigaltstack, void (*func)() )
 681 {
 682     struct sigaction sig_act;
 683
 684 #ifdef linux
 685     if (!have_sigaltstack && NtCurrentTeb()->signal_stack)
 686     {
 687         struct kernel_sigaction sig_act;
 688         sig_act.ksa_handler = func;
 689         sig_act.ksa_flags   = SA_RESTART | SA_NOMASK;
 690         sig_act.ksa_mask    = 0;
 691         /* point to the top of the stack */
 692         sig_act.ksa_restorer = (char *)NtCurrentTeb()->signal_stack + SIGNAL_STACK_SIZE;
 693         return wine_sigaction( sig, &sig_act, NULL );
 694     }
 695 #endif  /* linux */
 696     sig_act.sa_handler = func;
 697     sigemptyset( &sig_act.sa_mask );
 698
 699 #ifdef linux
 700     sig_act.sa_flags = SA_RESTART | SA_NOMASK;
 701 #elif defined (__svr4__) || defined(_SCO_DS)
 702     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
 703 #else
 704     sig_act.sa_flags = 0;
 705 #endif
 706
 707 #ifdef SA_ONSTACK
 708     if (have_sigaltstack) sig_act.sa_flags |= SA_ONSTACK;
 709 #endif
 710     return sigaction( sig, &sig_act, NULL );
 711 }
 712
 713
 714 /**********************************************************************
 715  *              SIGNAL_Init
 716  */
 717 BOOL SIGNAL_Init(void)
 718 {
 719     int have_sigaltstack = 0;
 720
 721 #ifdef HAVE_SIGALTSTACK
 722     struct sigaltstack ss;
 723     if ((ss.ss_sp = NtCurrentTeb()->signal_stack))
 724     {
 725         ss.ss_size  = SIGNAL_STACK_SIZE;
 726         ss.ss_flags = 0;
 727         if (!sigaltstack(&ss, NULL)) have_sigaltstack = 1;
 728 #ifdef linux
 729         /* sigaltstack may fail because the kernel is too old, or
 730            because glibc is brain-dead. In the latter case a
 731            direct system call should succeed. */
 732         else if (!wine_sigaltstack(&ss, NULL)) have_sigaltstack = 1;
 733 #endif  /* linux */
 734     }
 735 #endif  /* HAVE_SIGALTSTACK */
 736
 737     /* ignore SIGPIPE so that WINSOCK can get a EPIPE error instead  */
 738     signal( SIGPIPE, SIG_IGN );
 739     /* automatic child reaping to avoid zombies */
 740     signal( SIGCHLD, SIG_IGN );
 741
 742     if (set_handler( SIGINT,  have_sigaltstack, (void (*)())int_handler ) == -1) goto error;
 743     if (set_handler( SIGFPE,  have_sigaltstack, (void (*)())fpe_handler ) == -1) goto error;
 744     if (set_handler( SIGSEGV, have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
 745     if (set_handler( SIGILL,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
 746 #ifdef SIGBUS
 747     if (set_handler( SIGBUS,  have_sigaltstack, (void (*)())segv_handler ) == -1) goto error;
 748 #endif
 749 #ifdef SIGTRAP
 750     if (set_handler( SIGTRAP, have_sigaltstack, (void (*)())trap_handler ) == -1) goto error;
 751 #endif
 752     return TRUE;
 753
 754  error:
 755     perror("sigaction");
 756     return FALSE;
 757 }
 758
 759 /**********************************************************************
 760  *              DbgBreakPoint   (NTDLL)
 761  */
 762 void WINAPI DbgBreakPoint(void);
 763 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret");
 764
 765 /**********************************************************************
 766  *              DbgUserBreakPoint   (NTDLL)
 767  */
 768 void WINAPI DbgUserBreakPoint(void);
 769 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret");
 770
 771 #endif  /* __i386__ */