dlls/ntdll/signal_i386.c

   1 /*
   2  * i386 signal handling routines
   3  *
   4  * Copyright 1999 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #ifdef __i386__
  22
  23 #include "config.h"
  24 #include "wine/port.h"
  25
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdlib.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #include <sys/types.h>
  32 #ifdef HAVE_UNISTD_H
  33 # include <unistd.h>
  34 #endif
  35
  36 #ifdef HAVE_SYS_PARAM_H
  37 # include <sys/param.h>
  38 #endif
  39 #ifdef HAVE_SYSCALL_H
  40 # include <syscall.h>
  41 #else
  42 # ifdef HAVE_SYS_SYSCALL_H
  43 #  include <sys/syscall.h>
  44 # endif
  45 #endif
  46
  47 #ifdef HAVE_SYS_VM86_H
  48 # include <sys/vm86.h>
  49 #endif
  50
  51 #ifdef HAVE_SYS_SIGNAL_H
  52 # include <sys/signal.h>
  53 #endif
  54 #ifdef HAVE_SYS_SYSCTL_H
  55 # include <sys/sysctl.h>
  56 #endif
  57
  58 #include "windef.h"
  59 #include "thread.h"
  60 #include "wine/library.h"
  61 #include "ntdll_misc.h"
  62 #include "wine/exception.h"
  63 #include "wine/debug.h"
  64
  65 #ifdef HAVE_VALGRIND_MEMCHECK_H
  66 #include <valgrind/memcheck.h>
  67 #endif
  68
  69 #undef ERR  /* Solaris needs to define this */
  70
  71 /***********************************************************************
  72  * signal context platform-specific definitions
  73  */
  74
  75 #ifdef linux
  76
  77 typedef ucontext_t SIGCONTEXT;
  78
  79 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[REG_EAX])
  80 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[REG_EBX])
  81 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[REG_ECX])
  82 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[REG_EDX])
  83 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[REG_ESI])
  84 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[REG_EDI])
  85 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[REG_EBP])
  86 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[REG_ESP])
  87
  88 #define CS_sig(context)      ((context)->uc_mcontext.gregs[REG_CS])
  89 #define DS_sig(context)      ((context)->uc_mcontext.gregs[REG_DS])
  90 #define ES_sig(context)      ((context)->uc_mcontext.gregs[REG_ES])
  91 #define SS_sig(context)      ((context)->uc_mcontext.gregs[REG_SS])
  92 #define FS_sig(context)      ((context)->uc_mcontext.gregs[REG_FS])
  93 #define GS_sig(context)      ((context)->uc_mcontext.gregs[REG_GS])
  94
  95 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[REG_EFL])
  96 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
  97 #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
  98 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
  99
 100 #define FPU_sig(context)     ((FLOATING_SAVE_AREA*)((context)->uc_mcontext.fpregs))
 101
 102 #define VM86_EAX 0 /* the %eax value while vm86_enter is executing */
 103
 104 int vm86_enter( void **vm86_ptr );
 105 void vm86_return(void);
 106 void vm86_return_end(void);
 107 __ASM_GLOBAL_FUNC(vm86_enter,
 108                   "pushl %ebp\n\t"
 109                   "movl %esp, %ebp\n\t"
 110                   "movl $166,%eax\n\t"  /*SYS_vm86*/
 111                   "movl 8(%ebp),%ecx\n\t" /* vm86_ptr */
 112                   "movl (%ecx),%ecx\n\t"
 113                   "pushl %ebx\n\t"
 114                   "movl $1,%ebx\n\t"    /*VM86_ENTER*/
 115                   "pushl %ecx\n\t"      /* put vm86plus_struct ptr somewhere we can find it */
 116                   "pushl %fs\n\t"
 117                   "pushl %gs\n\t"
 118                   "int $0x80\n"
 119                   ".globl " __ASM_NAME("vm86_return") "\n\t"
 120                   __ASM_FUNC("vm86_return") "\n"
 121                   __ASM_NAME("vm86_return") ":\n\t"
 122                   "popl %gs\n\t"
 123                   "popl %fs\n\t"
 124                   "popl %ecx\n\t"
 125                   "popl %ebx\n\t"
 126                   "popl %ebp\n\t"
 127                   "testl %eax,%eax\n\t"
 128                   "jl 0f\n\t"
 129                   "cmpb $0,%al\n\t" /* VM86_SIGNAL */
 130                   "je " __ASM_NAME("vm86_enter") "\n\t"
 131                   "0:\n\t"
 132                   "movl 4(%esp),%ecx\n\t"  /* vm86_ptr */
 133                   "movl $0,(%ecx)\n\t"
 134                   ".globl " __ASM_NAME("vm86_return_end") "\n\t"
 135                   __ASM_FUNC("vm86_return_end") "\n"
 136                   __ASM_NAME("vm86_return_end") ":\n\t"
 137                   "ret" )
 138
 139 #ifdef HAVE_SYS_VM86_H
 140 # define __HAVE_VM86
 141 #endif
 142
 143 #endif  /* linux */
 144
 145 #ifdef BSDI
 146
 147 #include <machine/frame.h>
 148 typedef struct trapframe SIGCONTEXT;
 149
 150 #define EAX_sig(context)     ((context)->tf_eax)
 151 #define EBX_sig(context)     ((context)->tf_ebx)
 152 #define ECX_sig(context)     ((context)->tf_ecx)
 153 #define EDX_sig(context)     ((context)->tf_edx)
 154 #define ESI_sig(context)     ((context)->tf_esi)
 155 #define EDI_sig(context)     ((context)->tf_edi)
 156 #define EBP_sig(context)     ((context)->tf_ebp)
 157
 158 #define CS_sig(context)      ((context)->tf_cs)
 159 #define DS_sig(context)      ((context)->tf_ds)
 160 #define ES_sig(context)      ((context)->tf_es)
 161 #define SS_sig(context)      ((context)->tf_ss)
 162
 163 #define EFL_sig(context)     ((context)->tf_eflags)
 164
 165 #define EIP_sig(context)     (*((unsigned long*)&(context)->tf_eip))
 166 #define ESP_sig(context)     (*((unsigned long*)&(context)->tf_esp))
 167
 168 #endif /* bsdi */
 169
 170 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 171
 172 typedef struct sigcontext SIGCONTEXT;
 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 FS_sig(context)      ((context)->sc_fs)
 186 #define GS_sig(context)      ((context)->sc_gs)
 187 #define SS_sig(context)      ((context)->sc_ss)
 188
 189 #define TRAP_sig(context)    ((context)->sc_trapno)
 190 #define ERROR_sig(context)   ((context)->sc_err)
 191 #define EFL_sig(context)     ((context)->sc_eflags)
 192
 193 #define EIP_sig(context)     ((context)->sc_eip)
 194 #define ESP_sig(context)     ((context)->sc_esp)
 195
 196 #endif  /* *BSD */
 197
 198 #if defined(__svr4__) || defined(_SCO_DS) || defined(__sun)
 199
 200 #ifdef _SCO_DS
 201 #include <sys/regset.h>
 202 #endif
 203 #include <sys/ucontext.h>
 204 typedef struct ucontext SIGCONTEXT;
 205
 206 #ifdef _SCO_DS
 207 #define gregs regs
 208 #endif
 209
 210 #define EAX_sig(context)     ((context)->uc_mcontext.gregs[EAX])
 211 #define EBX_sig(context)     ((context)->uc_mcontext.gregs[EBX])
 212 #define ECX_sig(context)     ((context)->uc_mcontext.gregs[ECX])
 213 #define EDX_sig(context)     ((context)->uc_mcontext.gregs[EDX])
 214 #define ESI_sig(context)     ((context)->uc_mcontext.gregs[ESI])
 215 #define EDI_sig(context)     ((context)->uc_mcontext.gregs[EDI])
 216 #define EBP_sig(context)     ((context)->uc_mcontext.gregs[EBP])
 217
 218 #define CS_sig(context)      ((context)->uc_mcontext.gregs[CS])
 219 #define DS_sig(context)      ((context)->uc_mcontext.gregs[DS])
 220 #define ES_sig(context)      ((context)->uc_mcontext.gregs[ES])
 221 #define SS_sig(context)      ((context)->uc_mcontext.gregs[SS])
 222
 223 #define FS_sig(context)      ((context)->uc_mcontext.gregs[FS])
 224 #define GS_sig(context)      ((context)->uc_mcontext.gregs[GS])
 225
 226 #define EFL_sig(context)     ((context)->uc_mcontext.gregs[EFL])
 227
 228 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[EIP])
 229 #ifdef UESP
 230 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[UESP])
 231 #elif defined(R_ESP)
 232 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[R_ESP])
 233 #else
 234 #define ESP_sig(context)     ((context)->uc_mcontext.gregs[ESP])
 235 #endif
 236 #ifdef ERR
 237 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[ERR])
 238 #endif
 239 #ifdef TRAPNO
 240 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[TRAPNO])
 241 #endif
 242
 243 #endif  /* svr4 || SCO_DS */
 244
 245 #ifdef __APPLE__
 246 # include <sys/ucontext.h>
 247
 248 typedef ucontext_t SIGCONTEXT;
 249
 250 /* work around silly renaming of struct members in OS X 10.5 */
 251 #if __DARWIN_UNIX03 && defined(_STRUCT_X86_EXCEPTION_STATE32)
 252 #define EAX_sig(context)     ((context)->uc_mcontext->__ss.__eax)
 253 #define EBX_sig(context)     ((context)->uc_mcontext->__ss.__ebx)
 254 #define ECX_sig(context)     ((context)->uc_mcontext->__ss.__ecx)
 255 #define EDX_sig(context)     ((context)->uc_mcontext->__ss.__edx)
 256 #define ESI_sig(context)     ((context)->uc_mcontext->__ss.__esi)
 257 #define EDI_sig(context)     ((context)->uc_mcontext->__ss.__edi)
 258 #define EBP_sig(context)     ((context)->uc_mcontext->__ss.__ebp)
 259 #define CS_sig(context)      ((context)->uc_mcontext->__ss.__cs)
 260 #define DS_sig(context)      ((context)->uc_mcontext->__ss.__ds)
 261 #define ES_sig(context)      ((context)->uc_mcontext->__ss.__es)
 262 #define FS_sig(context)      ((context)->uc_mcontext->__ss.__fs)
 263 #define GS_sig(context)      ((context)->uc_mcontext->__ss.__gs)
 264 #define SS_sig(context)      ((context)->uc_mcontext->__ss.__ss)
 265 #define EFL_sig(context)     ((context)->uc_mcontext->__ss.__eflags)
 266 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__eip))
 267 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->__ss.__esp))
 268 #define TRAP_sig(context)    ((context)->uc_mcontext->__es.__trapno)
 269 #define ERROR_sig(context)   ((context)->uc_mcontext->__es.__err)
 270 #else
 271 #define EAX_sig(context)     ((context)->uc_mcontext->ss.eax)
 272 #define EBX_sig(context)     ((context)->uc_mcontext->ss.ebx)
 273 #define ECX_sig(context)     ((context)->uc_mcontext->ss.ecx)
 274 #define EDX_sig(context)     ((context)->uc_mcontext->ss.edx)
 275 #define ESI_sig(context)     ((context)->uc_mcontext->ss.esi)
 276 #define EDI_sig(context)     ((context)->uc_mcontext->ss.edi)
 277 #define EBP_sig(context)     ((context)->uc_mcontext->ss.ebp)
 278 #define CS_sig(context)      ((context)->uc_mcontext->ss.cs)
 279 #define DS_sig(context)      ((context)->uc_mcontext->ss.ds)
 280 #define ES_sig(context)      ((context)->uc_mcontext->ss.es)
 281 #define FS_sig(context)      ((context)->uc_mcontext->ss.fs)
 282 #define GS_sig(context)      ((context)->uc_mcontext->ss.gs)
 283 #define SS_sig(context)      ((context)->uc_mcontext->ss.ss)
 284 #define EFL_sig(context)     ((context)->uc_mcontext->ss.eflags)
 285 #define EIP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.eip))
 286 #define ESP_sig(context)     (*((unsigned long*)&(context)->uc_mcontext->ss.esp))
 287 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 288 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 289 #endif
 290
 291 #endif /* __APPLE__ */
 292
 293 WINE_DEFAULT_DEBUG_CHANNEL(seh);
 294
 295 typedef int (*wine_signal_handler)(unsigned int sig);
 296
 297 static size_t signal_stack_mask;
 298 static size_t signal_stack_size;
 299
 300 static wine_signal_handler handlers[256];
 301
 302 extern void DECLSPEC_NORETURN __wine_call_from_32_restore_regs( const CONTEXT *context );
 303
 304 enum i386_trap_code
 305 {
 306     TRAP_x86_UNKNOWN    = -1,  /* Unknown fault (TRAP_sig not defined) */
 307 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 308     TRAP_x86_DIVIDE     = T_DIVIDE,     /* Division by zero exception */
 309     TRAP_x86_TRCTRAP    = T_TRCTRAP,    /* Single-step exception */
 310     TRAP_x86_NMI        = T_NMI,        /* NMI interrupt */
 311     TRAP_x86_BPTFLT     = T_BPTFLT,     /* Breakpoint exception */
 312     TRAP_x86_OFLOW      = T_OFLOW,      /* Overflow exception */
 313     TRAP_x86_BOUND      = T_BOUND,      /* Bound range exception */
 314     TRAP_x86_PRIVINFLT  = T_PRIVINFLT,  /* Invalid opcode exception */
 315     TRAP_x86_DNA        = T_DNA,        /* Device not available exception */
 316     TRAP_x86_DOUBLEFLT  = T_DOUBLEFLT,  /* Double fault exception */
 317     TRAP_x86_FPOPFLT    = T_FPOPFLT,    /* Coprocessor segment overrun */
 318     TRAP_x86_TSSFLT     = T_TSSFLT,     /* Invalid TSS exception */
 319     TRAP_x86_SEGNPFLT   = T_SEGNPFLT,   /* Segment not present exception */
 320     TRAP_x86_STKFLT     = T_STKFLT,     /* Stack fault */
 321     TRAP_x86_PROTFLT    = T_PROTFLT,    /* General protection fault */
 322     TRAP_x86_PAGEFLT    = T_PAGEFLT,    /* Page fault */
 323     TRAP_x86_ARITHTRAP  = T_ARITHTRAP,  /* Floating point exception */
 324     TRAP_x86_ALIGNFLT   = T_ALIGNFLT,   /* Alignment check exception */
 325     TRAP_x86_MCHK       = T_MCHK,       /* Machine check exception */
 326     TRAP_x86_CACHEFLT   = T_XMMFLT      /* Cache flush exception */
 327 #else
 328     TRAP_x86_DIVIDE     = 0,   /* Division by zero exception */
 329     TRAP_x86_TRCTRAP    = 1,   /* Single-step exception */
 330     TRAP_x86_NMI        = 2,   /* NMI interrupt */
 331     TRAP_x86_BPTFLT     = 3,   /* Breakpoint exception */
 332     TRAP_x86_OFLOW      = 4,   /* Overflow exception */
 333     TRAP_x86_BOUND      = 5,   /* Bound range exception */
 334     TRAP_x86_PRIVINFLT  = 6,   /* Invalid opcode exception */
 335     TRAP_x86_DNA        = 7,   /* Device not available exception */
 336     TRAP_x86_DOUBLEFLT  = 8,   /* Double fault exception */
 337     TRAP_x86_FPOPFLT    = 9,   /* Coprocessor segment overrun */
 338     TRAP_x86_TSSFLT     = 10,  /* Invalid TSS exception */
 339     TRAP_x86_SEGNPFLT   = 11,  /* Segment not present exception */
 340     TRAP_x86_STKFLT     = 12,  /* Stack fault */
 341     TRAP_x86_PROTFLT    = 13,  /* General protection fault */
 342     TRAP_x86_PAGEFLT    = 14,  /* Page fault */
 343     TRAP_x86_ARITHTRAP  = 16,  /* Floating point exception */
 344     TRAP_x86_ALIGNFLT   = 17,  /* Alignment check exception */
 345     TRAP_x86_MCHK       = 18,  /* Machine check exception */
 346     TRAP_x86_CACHEFLT   = 19   /* SIMD exception (via SIGFPE) if CPU is SSE capable
 347                                   otherwise Cache flush exception (via SIGSEV) */
 348 #endif
 349 };
 350
 351
 352 /***********************************************************************
 353  *           dispatch_signal
 354  */
 355 static inline int dispatch_signal(unsigned int sig)
 356 {
 357     if (handlers[sig] == NULL) return 0;
 358     return handlers[sig](sig);
 359 }
 360
 361
 362 /***********************************************************************
 363  *           get_trap_code
 364  *
 365  * Get the trap code for a signal.
 366  */
 367 static inline enum i386_trap_code get_trap_code( const SIGCONTEXT *sigcontext )
 368 {
 369 #ifdef TRAP_sig
 370     return TRAP_sig(sigcontext);
 371 #else
 372     return TRAP_x86_UNKNOWN;  /* unknown trap code */
 373 #endif
 374 }
 375
 376 /***********************************************************************
 377  *           get_error_code
 378  *
 379  * Get the error code for a signal.
 380  */
 381 static inline WORD get_error_code( const SIGCONTEXT *sigcontext )
 382 {
 383 #ifdef ERROR_sig
 384     return ERROR_sig(sigcontext);
 385 #else
 386     return 0;
 387 #endif
 388 }
 389
 390 /***********************************************************************
 391  *           get_signal_stack
 392  *
 393  * Get the base of the signal stack for the current thread.
 394  */
 395 static inline void *get_signal_stack(void)
 396 {
 397     return (char *)NtCurrentTeb() + 4096;
 398 }
 399
 400
 401 /***********************************************************************
 402  *           get_current_teb
 403  *
 404  * Get the current teb based on the stack pointer.
 405  */
 406 static inline TEB *get_current_teb(void)
 407 {
 408     unsigned long esp;
 409     __asm__("movl %%esp,%0" : "=g" (esp) );
 410     return (TEB *)(esp & ~signal_stack_mask);
 411 }
 412
 413
 414 #ifdef __HAVE_VM86
 415 /***********************************************************************
 416  *           save_vm86_context
 417  *
 418  * Set the register values from a vm86 structure.
 419  */
 420 static void save_vm86_context( CONTEXT *context, const struct vm86plus_struct *vm86 )
 421 {
 422     context->ContextFlags = CONTEXT_FULL;
 423     context->Eax    = vm86->regs.eax;
 424     context->Ebx    = vm86->regs.ebx;
 425     context->Ecx    = vm86->regs.ecx;
 426     context->Edx    = vm86->regs.edx;
 427     context->Esi    = vm86->regs.esi;
 428     context->Edi    = vm86->regs.edi;
 429     context->Esp    = vm86->regs.esp;
 430     context->Ebp    = vm86->regs.ebp;
 431     context->Eip    = vm86->regs.eip;
 432     context->SegCs  = vm86->regs.cs;
 433     context->SegDs  = vm86->regs.ds;
 434     context->SegEs  = vm86->regs.es;
 435     context->SegFs  = vm86->regs.fs;
 436     context->SegGs  = vm86->regs.gs;
 437     context->SegSs  = vm86->regs.ss;
 438     context->EFlags = vm86->regs.eflags;
 439 }
 440
 441
 442 /***********************************************************************
 443  *           restore_vm86_context
 444  *
 445  * Build a vm86 structure from the register values.
 446  */
 447 static void restore_vm86_context( const CONTEXT *context, struct vm86plus_struct *vm86 )
 448 {
 449     vm86->regs.eax    = context->Eax;
 450     vm86->regs.ebx    = context->Ebx;
 451     vm86->regs.ecx    = context->Ecx;
 452     vm86->regs.edx    = context->Edx;
 453     vm86->regs.esi    = context->Esi;
 454     vm86->regs.edi    = context->Edi;
 455     vm86->regs.esp    = context->Esp;
 456     vm86->regs.ebp    = context->Ebp;
 457     vm86->regs.eip    = context->Eip;
 458     vm86->regs.cs     = context->SegCs;
 459     vm86->regs.ds     = context->SegDs;
 460     vm86->regs.es     = context->SegEs;
 461     vm86->regs.fs     = context->SegFs;
 462     vm86->regs.gs     = context->SegGs;
 463     vm86->regs.ss     = context->SegSs;
 464     vm86->regs.eflags = context->EFlags;
 465 }
 466
 467
 468 /**********************************************************************
 469  *              merge_vm86_pending_flags
 470  *
 471  * Merges TEB.vm86_ptr and TEB.vm86_pending VIP flags and
 472  * raises exception if there are pending events and VIF flag
 473  * has been turned on.
 474  *
 475  * Called from __wine_enter_vm86 because vm86_enter
 476  * doesn't check for pending events.
 477  *
 478  * Called from raise_vm86_sti_exception to check for
 479  * pending events in a signal safe way.
 480  */
 481 static void merge_vm86_pending_flags( EXCEPTION_RECORD *rec )
 482 {
 483     BOOL check_pending = TRUE;
 484     struct vm86plus_struct *vm86 =
 485         (struct vm86plus_struct*)(ntdll_get_thread_data()->vm86_ptr);
 486
 487     /*
 488      * In order to prevent a race when SIGUSR2 occurs while
 489      * we are returning from exception handler, pending events
 490      * will be rechecked after each raised exception.
 491      */
 492     while (check_pending && NtCurrentTeb()->vm86_pending)
 493     {
 494         check_pending = FALSE;
 495         ntdll_get_thread_data()->vm86_ptr = NULL;
 496
 497         /*
 498          * If VIF is set, throw exception.
 499          * Note that SIGUSR2 may turn VIF flag off so
 500          * VIF check must occur only when TEB.vm86_ptr is NULL.
 501          */
 502         if (vm86->regs.eflags & VIF_MASK)
 503         {
 504             CONTEXT vcontext;
 505             save_vm86_context( &vcontext, vm86 );
 506
 507             rec->ExceptionCode    = EXCEPTION_VM86_STI;
 508             rec->ExceptionFlags   = EXCEPTION_CONTINUABLE;
 509             rec->ExceptionRecord  = NULL;
 510             rec->NumberParameters = 0;
 511             rec->ExceptionAddress = (LPVOID)vcontext.Eip;
 512
 513             vcontext.EFlags &= ~VIP_MASK;
 514             NtCurrentTeb()->vm86_pending = 0;
 515             __regs_RtlRaiseException( rec, &vcontext );
 516
 517             restore_vm86_context( &vcontext, vm86 );
 518             check_pending = TRUE;
 519         }
 520
 521         ntdll_get_thread_data()->vm86_ptr = vm86;
 522     }
 523
 524     /*
 525      * Merge VIP flags in a signal safe way. This requires
 526      * that the following operation compiles into atomic
 527      * instruction.
 528      */
 529     vm86->regs.eflags |= NtCurrentTeb()->vm86_pending;
 530 }
 531 #endif /* __HAVE_VM86 */
 532
 533
 534 typedef void (WINAPI *raise_func)( EXCEPTION_RECORD *rec, CONTEXT *context );
 535
 536
 537 /***********************************************************************
 538  *           init_handler
 539  *
 540  * Handler initialization when the full context is not needed.
 541  */
 542 static inline void *init_handler( const SIGCONTEXT *sigcontext, WORD *fs, WORD *gs )
 543 {
 544     void *stack = (void *)(ESP_sig(sigcontext) & ~3);
 545     TEB *teb = get_current_teb();
 546     struct ntdll_thread_data *thread_data = (struct ntdll_thread_data *)teb->SystemReserved2;
 547
 548     /* get %fs and %gs at time of the fault */
 549 #ifdef FS_sig
 550     *fs = LOWORD(FS_sig(sigcontext));
 551 #else
 552     *fs = wine_get_fs();
 553 #endif
 554 #ifdef GS_sig
 555     *gs = LOWORD(GS_sig(sigcontext));
 556 #else
 557     *gs = wine_get_gs();
 558 #endif
 559
 560     wine_set_fs( thread_data->fs );
 561
 562     /* now restore a proper %gs for the fault handler */
 563     if (!wine_ldt_is_system(CS_sig(sigcontext)) ||
 564         !wine_ldt_is_system(SS_sig(sigcontext)))  /* 16-bit mode */
 565     {
 566         /*
 567          * Win16 or DOS protected mode. Note that during switch
 568          * from 16-bit mode to linear mode, CS may be set to system
 569          * segment before FS is restored. Fortunately, in this case
 570          * SS is still non-system segment. This is why both CS and SS
 571          * are checked.
 572          */
 573         wine_set_gs( thread_data->gs );
 574         stack = teb->WOW32Reserved;
 575     }
 576 #ifdef __HAVE_VM86
 577     else if ((void *)EIP_sig(sigcontext) == vm86_return)  /* vm86 mode */
 578     {
 579         unsigned int *int_stack = stack;
 580         /* fetch the saved %gs from the stack */
 581         wine_set_gs( int_stack[0] );
 582     }
 583 #endif
 584     else  /* 32-bit mode */
 585     {
 586 #ifdef GS_sig
 587         wine_set_gs( GS_sig(sigcontext) );
 588 #endif
 589     }
 590     return stack;
 591 }
 592
 593
 594 /***********************************************************************
 595  *           save_fpu
 596  *
 597  * Save the thread FPU context.
 598  */
 599 static inline void save_fpu( CONTEXT *context )
 600 {
 601 #ifdef __GNUC__
 602     context->ContextFlags |= CONTEXT_FLOATING_POINT;
 603     __asm__ __volatile__( "fnsave %0; fwait" : "=m" (context->FloatSave) );
 604 #endif
 605 }
 606
 607
 608 /***********************************************************************
 609  *           restore_fpu
 610  *
 611  * Restore the FPU context to a sigcontext.
 612  */
 613 static inline void restore_fpu( const CONTEXT *context )
 614 {
 615     FLOATING_SAVE_AREA float_status = context->FloatSave;
 616     /* reset the current interrupt status */
 617     float_status.StatusWord &= float_status.ControlWord | 0xffffff80;
 618 #ifdef __GNUC__
 619     __asm__ __volatile__( "frstor %0; fwait" : : "m" (float_status) );
 620 #endif  /* __GNUC__ */
 621 }
 622
 623
 624 /***********************************************************************
 625  *           save_context
 626  *
 627  * Build a context structure from the signal info.
 628  */
 629 static inline void save_context( CONTEXT *context, const SIGCONTEXT *sigcontext, WORD fs, WORD gs )
 630 {
 631     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 632
 633     memset(context, 0, sizeof(*context));
 634     context->ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
 635     context->Eax          = EAX_sig(sigcontext);
 636     context->Ebx          = EBX_sig(sigcontext);
 637     context->Ecx          = ECX_sig(sigcontext);
 638     context->Edx          = EDX_sig(sigcontext);
 639     context->Esi          = ESI_sig(sigcontext);
 640     context->Edi          = EDI_sig(sigcontext);
 641     context->Ebp          = EBP_sig(sigcontext);
 642     context->EFlags       = EFL_sig(sigcontext);
 643     context->Eip          = EIP_sig(sigcontext);
 644     context->Esp          = ESP_sig(sigcontext);
 645     context->SegCs        = LOWORD(CS_sig(sigcontext));
 646     context->SegDs        = LOWORD(DS_sig(sigcontext));
 647     context->SegEs        = LOWORD(ES_sig(sigcontext));
 648     context->SegFs        = fs;
 649     context->SegGs        = gs;
 650     context->SegSs        = LOWORD(SS_sig(sigcontext));
 651     context->Dr0          = regs->dr0;
 652     context->Dr1          = regs->dr1;
 653     context->Dr2          = regs->dr2;
 654     context->Dr3          = regs->dr3;
 655     context->Dr6          = regs->dr6;
 656     context->Dr7          = regs->dr7;
 657
 658 #ifdef FPU_sig
 659     if (FPU_sig(sigcontext))
 660     {
 661         context->ContextFlags |= CONTEXT_FLOATING_POINT;
 662         context->FloatSave = *FPU_sig(sigcontext);
 663     }
 664     else
 665 #endif
 666     {
 667         save_fpu( context );
 668     }
 669 }
 670
 671
 672 /***********************************************************************
 673  *           restore_context
 674  *
 675  * Restore the signal info from the context.
 676  */
 677 static inline void restore_context( const CONTEXT *context, SIGCONTEXT *sigcontext )
 678 {
 679     struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 680
 681     regs->dr0 = context->Dr0;
 682     regs->dr1 = context->Dr1;
 683     regs->dr2 = context->Dr2;
 684     regs->dr3 = context->Dr3;
 685     regs->dr6 = context->Dr6;
 686     regs->dr7 = context->Dr7;
 687     EAX_sig(sigcontext) = context->Eax;
 688     EBX_sig(sigcontext) = context->Ebx;
 689     ECX_sig(sigcontext) = context->Ecx;
 690     EDX_sig(sigcontext) = context->Edx;
 691     ESI_sig(sigcontext) = context->Esi;
 692     EDI_sig(sigcontext) = context->Edi;
 693     EBP_sig(sigcontext) = context->Ebp;
 694     EFL_sig(sigcontext) = context->EFlags;
 695     EIP_sig(sigcontext) = context->Eip;
 696     ESP_sig(sigcontext) = context->Esp;
 697     CS_sig(sigcontext)  = context->SegCs;
 698     DS_sig(sigcontext)  = context->SegDs;
 699     ES_sig(sigcontext)  = context->SegEs;
 700     SS_sig(sigcontext)  = context->SegSs;
 701 #ifdef GS_sig
 702     GS_sig(sigcontext)  = context->SegGs;
 703 #else
 704     wine_set_gs( context->SegGs );
 705 #endif
 706 #ifdef FS_sig
 707     FS_sig(sigcontext)  = context->SegFs;
 708 #else
 709     wine_set_fs( context->SegFs );
 710 #endif
 711
 712 #ifdef FPU_sig
 713     if (FPU_sig(sigcontext))
 714     {
 715         *FPU_sig(sigcontext) = context->FloatSave;
 716     }
 717     else
 718 #endif
 719     {
 720         restore_fpu( context );
 721     }
 722 }
 723
 724
 725 /***********************************************************************
 726  *              get_cpu_context
 727  *
 728  * Register function to get the context of the current thread.
 729  */
 730 void WINAPI __regs_get_cpu_context( CONTEXT *context, CONTEXT *regs )
 731 {
 732     *context = *regs;
 733     save_fpu( context );
 734 }
 735 DEFINE_REGS_ENTRYPOINT( get_cpu_context, 4, 4 )
 736
 737
 738 /***********************************************************************
 739  *           set_cpu_context
 740  *
 741  * Set the new CPU context. Used by NtSetContextThread.
 742  */
 743 void set_cpu_context( const CONTEXT *context )
 744 {
 745     DWORD flags = context->ContextFlags & ~CONTEXT_i386;
 746
 747     if (flags & CONTEXT_FLOATING_POINT) restore_fpu( context );
 748
 749     if (flags & CONTEXT_DEBUG_REGISTERS)
 750     {
 751         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
 752         regs->dr0 = context->Dr0;
 753         regs->dr1 = context->Dr1;
 754         regs->dr2 = context->Dr2;
 755         regs->dr3 = context->Dr3;
 756         regs->dr6 = context->Dr6;
 757         regs->dr7 = context->Dr7;
 758     }
 759     if (flags & CONTEXT_FULL)
 760     {
 761         if (!(flags & CONTEXT_CONTROL))
 762             FIXME( "setting partial context (%x) not supported\n", flags );
 763         else if (flags & CONTEXT_SEGMENTS)
 764             __wine_call_from_32_restore_regs( context );
 765         else
 766         {
 767             CONTEXT newcontext = *context;
 768             newcontext.SegDs = wine_get_ds();
 769             newcontext.SegEs = wine_get_es();
 770             newcontext.SegFs = wine_get_fs();
 771             newcontext.SegGs = wine_get_gs();
 772             __wine_call_from_32_restore_regs( &newcontext );
 773         }
 774     }
 775 }
 776
 777
 778 /***********************************************************************
 779  *           is_privileged_instr
 780  *
 781  * Check if the fault location is a privileged instruction.
 782  * Based on the instruction emulation code in dlls/kernel/instr.c.
 783  */
 784 static inline DWORD is_privileged_instr( CONTEXT86 *context )
 785 {
 786     const BYTE *instr;
 787     unsigned int prefix_count = 0;
 788
 789     if (!wine_ldt_is_system( context->SegCs )) return 0;
 790     instr = (BYTE *)context->Eip;
 791
 792     for (;;) switch(*instr)
 793     {
 794     /* instruction prefixes */
 795     case 0x2e:  /* %cs: */
 796     case 0x36:  /* %ss: */
 797     case 0x3e:  /* %ds: */
 798     case 0x26:  /* %es: */
 799     case 0x64:  /* %fs: */
 800     case 0x65:  /* %gs: */
 801     case 0x66:  /* opcode size */
 802     case 0x67:  /* addr size */
 803     case 0xf0:  /* lock */
 804     case 0xf2:  /* repne */
 805     case 0xf3:  /* repe */
 806         if (++prefix_count >= 15) return EXCEPTION_ILLEGAL_INSTRUCTION;
 807         instr++;
 808         continue;
 809
 810     case 0x0f: /* extended instruction */
 811         switch(instr[1])
 812         {
 813         case 0x20: /* mov crX, reg */
 814         case 0x21: /* mov drX, reg */
 815         case 0x22: /* mov reg, crX */
 816         case 0x23: /* mov reg drX */
 817             return EXCEPTION_PRIV_INSTRUCTION;
 818         }
 819         return 0;
 820     case 0x6c: /* insb (%dx) */
 821     case 0x6d: /* insl (%dx) */
 822     case 0x6e: /* outsb (%dx) */
 823     case 0x6f: /* outsl (%dx) */
 824     case 0xcd: /* int $xx */
 825     case 0xe4: /* inb al,XX */
 826     case 0xe5: /* in (e)ax,XX */
 827     case 0xe6: /* outb XX,al */
 828     case 0xe7: /* out XX,(e)ax */
 829     case 0xec: /* inb (%dx),%al */
 830     case 0xed: /* inl (%dx),%eax */
 831     case 0xee: /* outb %al,(%dx) */
 832     case 0xef: /* outl %eax,(%dx) */
 833     case 0xf4: /* hlt */
 834     case 0xfa: /* cli */
 835     case 0xfb: /* sti */
 836         return EXCEPTION_PRIV_INSTRUCTION;
 837     default:
 838         return 0;
 839     }
 840 }
 841
 842
 843 #include "pshpack1.h"
 844 struct atl_thunk
 845 {
 846     DWORD movl;  /* movl this,4(%esp) */
 847     DWORD this;
 848     BYTE  jmp;   /* jmp func */
 849     int   func;
 850 };
 851 #include "poppack.h"
 852
 853 /**********************************************************************
 854  *              check_atl_thunk
 855  *
 856  * Check if code destination is an ATL thunk, and emulate it if so.
 857  */
 858 static BOOL check_atl_thunk( EXCEPTION_RECORD *rec, CONTEXT *context )
 859 {
 860     const struct atl_thunk *thunk = (const struct atl_thunk *)rec->ExceptionInformation[1];
 861     BOOL ret = FALSE;
 862
 863     __TRY
 864     {
 865         if (thunk->movl == 0x042444c7 && thunk->jmp == 0xe9)
 866         {
 867             *((DWORD *)context->Esp + 1) = thunk->this;
 868             context->Eip = (DWORD_PTR)(&thunk->func + 1) + thunk->func;
 869             TRACE( "emulating ATL thunk at %p, func=%08x arg=%08x\n",
 870                    thunk, context->Eip, *((DWORD *)context->Esp + 1) );
 871             ret = TRUE;
 872         }
 873     }
 874     __EXCEPT_PAGE_FAULT
 875     {
 876         return FALSE;
 877     }
 878     __ENDTRY
 879     return ret;
 880 }
 881
 882
 883 /***********************************************************************
 884  *           setup_exception
 885  *
 886  * Setup a proper stack frame for the raise function, and modify the
 887  * sigcontext so that the return from the signal handler will call
 888  * the raise function.
 889  */
 890 static EXCEPTION_RECORD *setup_exception( SIGCONTEXT *sigcontext, raise_func func )
 891 {
 892     struct stack_layout
 893     {
 894         void             *ret_addr;      /* return address from raise_func */
 895         EXCEPTION_RECORD *rec_ptr;       /* first arg for raise_func */
 896         CONTEXT          *context_ptr;   /* second arg for raise_func */
 897         CONTEXT           context;
 898         EXCEPTION_RECORD  rec;
 899         DWORD             ebp;
 900         DWORD             eip;
 901     } *stack;
 902
 903     WORD fs, gs;
 904
 905     stack = init_handler( sigcontext, &fs, &gs );
 906
 907     /* stack sanity checks */
 908
 909     if ((char *)stack >= (char *)get_signal_stack() &&
 910         (char *)stack < (char *)get_signal_stack() + signal_stack_size)
 911     {
 912         WINE_ERR( "nested exception on signal stack in thread %04x eip %08x esp %08x stack %p-%p\n",
 913                   GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
 914                   (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
 915                   NtCurrentTeb()->Tib.StackBase );
 916         server_abort_thread(1);
 917     }
 918
 919     if (stack - 1 > stack || /* check for overflow in subtraction */
 920         (char *)(stack - 1) < (char *)NtCurrentTeb()->Tib.StackLimit ||
 921         (char *)stack > (char *)NtCurrentTeb()->Tib.StackBase)
 922     {
 923         UINT diff = (char *)NtCurrentTeb()->Tib.StackLimit - (char *)stack;
 924         if (diff < 4096)
 925         {
 926             WINE_ERR( "stack overflow %u bytes in thread %04x eip %08x esp %08x stack %p-%p\n",
 927                       diff, GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
 928                       (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
 929                       NtCurrentTeb()->Tib.StackBase );
 930             server_abort_thread(1);
 931         }
 932         else WARN( "exception outside of stack limits in thread %04x eip %08x esp %08x stack %p-%p\n",
 933                    GetCurrentThreadId(), (unsigned int) EIP_sig(sigcontext),
 934                    (unsigned int) ESP_sig(sigcontext), NtCurrentTeb()->Tib.StackLimit,
 935                    NtCurrentTeb()->Tib.StackBase );
 936     }
 937
 938     stack--;  /* push the stack_layout structure */
 939 #ifdef HAVE_VALGRIND_MEMCHECK_H
 940     VALGRIND_MAKE_WRITABLE(stack, sizeof(*stack));
 941 #endif
 942     stack->ret_addr     = (void *)0xdeadbabe;  /* raise_func must not return */
 943     stack->rec_ptr      = &stack->rec;
 944     stack->context_ptr  = &stack->context;
 945
 946     stack->rec.ExceptionRecord  = NULL;
 947     stack->rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
 948     stack->rec.ExceptionAddress = (LPVOID)EIP_sig(sigcontext);
 949     stack->rec.NumberParameters = 0;
 950
 951     save_context( &stack->context, sigcontext, fs, gs );
 952
 953     /* now modify the sigcontext to return to the raise function */
 954     ESP_sig(sigcontext) = (DWORD)stack;
 955     EIP_sig(sigcontext) = (DWORD)func;
 956     /* clear single-step and align check flag */
 957     EFL_sig(sigcontext) &= ~(0x100|0x40000);
 958     CS_sig(sigcontext)  = wine_get_cs();
 959     DS_sig(sigcontext)  = wine_get_ds();
 960     ES_sig(sigcontext)  = wine_get_es();
 961     FS_sig(sigcontext)  = wine_get_fs();
 962     GS_sig(sigcontext)  = wine_get_gs();
 963     SS_sig(sigcontext)  = wine_get_ss();
 964
 965     return stack->rec_ptr;
 966 }
 967
 968
 969 /***********************************************************************
 970  *           get_exception_context
 971  *
 972  * Get a pointer to the context built by setup_exception.
 973  */
 974 static inline CONTEXT *get_exception_context( EXCEPTION_RECORD *rec )
 975 {
 976     return (CONTEXT *)rec - 1;  /* cf. stack_layout structure */
 977 }
 978
 979
 980 /**********************************************************************
 981  *              get_fpu_code
 982  *
 983  * Get the FPU exception code from the FPU status.
 984  */
 985 static inline DWORD get_fpu_code( const CONTEXT *context )
 986 {
 987     DWORD status = context->FloatSave.StatusWord;
 988
 989     if (status & 0x01)  /* IE */
 990     {
 991         if (status & 0x40)  /* SF */
 992             return EXCEPTION_FLT_STACK_CHECK;
 993         else
 994             return EXCEPTION_FLT_INVALID_OPERATION;
 995     }
 996     if (status & 0x02) return EXCEPTION_FLT_DENORMAL_OPERAND;  /* DE flag */
 997     if (status & 0x04) return EXCEPTION_FLT_DIVIDE_BY_ZERO;    /* ZE flag */
 998     if (status & 0x08) return EXCEPTION_FLT_OVERFLOW;          /* OE flag */
 999     if (status & 0x10) return EXCEPTION_FLT_UNDERFLOW;         /* UE flag */
1000     if (status & 0x20) return EXCEPTION_FLT_INEXACT_RESULT;    /* PE flag */
1001     return EXCEPTION_FLT_INVALID_OPERATION;  /* generic error */
1002 }
1003
1004
1005 /**********************************************************************
1006  *              raise_segv_exception
1007  */
1008 static void WINAPI raise_segv_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1009 {
1010     switch(rec->ExceptionCode)
1011     {
1012     case EXCEPTION_ACCESS_VIOLATION:
1013         if (rec->NumberParameters == 2)
1014         {
1015             if (rec->ExceptionInformation[0] == EXCEPTION_EXECUTE_FAULT && check_atl_thunk( rec, context ))
1016                 goto done;
1017             rec->ExceptionCode = VIRTUAL_HandleFault( (void *)rec->ExceptionInformation[1] );
1018         }
1019         break;
1020     case EXCEPTION_DATATYPE_MISALIGNMENT:
1021         /* FIXME: pass through exception handler first? */
1022         if (context->EFlags & 0x00040000)
1023         {
1024             /* Disable AC flag, return */
1025             context->EFlags &= ~0x00040000;
1026             goto done;
1027         }
1028         break;
1029     }
1030     __regs_RtlRaiseException( rec, context );
1031 done:
1032     NtSetContextThread( GetCurrentThread(), context );
1033 }
1034
1035
1036 /**********************************************************************
1037  *              raise_trap_exception
1038  */
1039 static void WINAPI raise_trap_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1040 {
1041     if (rec->ExceptionCode == EXCEPTION_SINGLE_STEP)
1042     {
1043         struct ntdll_thread_regs * const regs = ntdll_get_thread_regs();
1044
1045         /* when single stepping can't tell whether this is a hw bp or a
1046          * single step interrupt. try to avoid as much overhead as possible
1047          * and only do a server call if there is any hw bp enabled. */
1048
1049         if( !(context->EFlags & 0x100) || (regs->dr7 & 0xff) )
1050         {
1051             /* (possible) hardware breakpoint, fetch the debug registers */
1052             context->ContextFlags = CONTEXT_DEBUG_REGISTERS;
1053             NtGetContextThread(GetCurrentThread(), context);
1054             context->ContextFlags |= CONTEXT_FULL;  /* restore flags */
1055         }
1056
1057         context->EFlags &= ~0x100;  /* clear single-step flag */
1058     }
1059
1060     __regs_RtlRaiseException( rec, context );
1061     NtSetContextThread( GetCurrentThread(), context );
1062 }
1063
1064
1065 /**********************************************************************
1066  *              raise_exception
1067  *
1068  * Generic raise function for exceptions that don't need special treatment.
1069  */
1070 static void WINAPI raise_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1071 {
1072     __regs_RtlRaiseException( rec, context );
1073     NtSetContextThread( GetCurrentThread(), context );
1074 }
1075
1076
1077 #ifdef __HAVE_VM86
1078 /**********************************************************************
1079  *              raise_vm86_sti_exception
1080  */
1081 static void WINAPI raise_vm86_sti_exception( EXCEPTION_RECORD *rec, CONTEXT *context )
1082 {
1083     /* merge_vm86_pending_flags merges the vm86_pending flag in safely */
1084     NtCurrentTeb()->vm86_pending |= VIP_MASK;
1085
1086     if (ntdll_get_thread_data()->vm86_ptr)
1087     {
1088         if (((char*)context->Eip >= (char*)vm86_return) &&
1089             ((char*)context->Eip <= (char*)vm86_return_end) &&
1090             (VM86_TYPE(context->Eax) != VM86_SIGNAL)) {
1091             /* exiting from VM86, can't throw */
1092             goto done;
1093         }
1094         merge_vm86_pending_flags( rec );
1095     }
1096     else if (NtCurrentTeb()->dpmi_vif &&
1097              !wine_ldt_is_system(context->SegCs) &&
1098              !wine_ldt_is_system(context->SegSs))
1099     {
1100         /* Executing DPMI code and virtual interrupts are enabled. */
1101         NtCurrentTeb()->vm86_pending = 0;
1102         __regs_RtlRaiseException( rec, context );
1103     }
1104 done:
1105     NtSetContextThread( GetCurrentThread(), context );
1106 }
1107
1108
1109 /**********************************************************************
1110  *              usr2_handler
1111  *
1112  * Handler for SIGUSR2.
1113  * We use it to signal that the running __wine_enter_vm86() should
1114  * immediately set VIP_MASK, causing pending events to be handled
1115  * as early as possible.
1116  */
1117 static void usr2_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1118 {
1119     EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_vm86_sti_exception );
1120     rec->ExceptionCode = EXCEPTION_VM86_STI;
1121 }
1122 #endif /* __HAVE_VM86 */
1123
1124
1125 /**********************************************************************
1126  *              segv_handler
1127  *
1128  * Handler for SIGSEGV and related errors.
1129  */
1130 static void segv_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1131 {
1132     SIGCONTEXT *context = sigcontext;
1133     EXCEPTION_RECORD *rec = setup_exception( context, raise_segv_exception );
1134
1135     switch(get_trap_code(context))
1136     {
1137     case TRAP_x86_OFLOW:   /* Overflow exception */
1138         rec->ExceptionCode = EXCEPTION_INT_OVERFLOW;
1139         break;
1140     case TRAP_x86_BOUND:   /* Bound range exception */
1141         rec->ExceptionCode = EXCEPTION_ARRAY_BOUNDS_EXCEEDED;
1142         break;
1143     case TRAP_x86_PRIVINFLT:   /* Invalid opcode exception */
1144         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1145         break;
1146     case TRAP_x86_STKFLT:  /* Stack fault */
1147         rec->ExceptionCode = EXCEPTION_STACK_OVERFLOW;
1148         break;
1149     case TRAP_x86_SEGNPFLT:  /* Segment not present exception */
1150     case TRAP_x86_PROTFLT:   /* General protection fault */
1151     case TRAP_x86_UNKNOWN:   /* Unknown fault code */
1152         {
1153             WORD err = get_error_code(context);
1154             if (!err && (rec->ExceptionCode = is_privileged_instr( get_exception_context(rec) ))) break;
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             if ((err & 7) == 4 && !wine_ldt_is_system( err | 7 ))
1160                 rec->ExceptionInformation[1] = err & ~7;
1161             else
1162                 rec->ExceptionInformation[1] = 0xffffffff;
1163         }
1164         break;
1165     case TRAP_x86_PAGEFLT:  /* Page fault */
1166         rec->ExceptionCode = EXCEPTION_ACCESS_VIOLATION;
1167         rec->NumberParameters = 2;
1168         rec->ExceptionInformation[0] = (get_error_code(context) >> 1) & 0x09;
1169         rec->ExceptionInformation[1] = (ULONG_PTR)siginfo->si_addr;
1170         break;
1171     case TRAP_x86_ALIGNFLT:  /* Alignment check exception */
1172         rec->ExceptionCode = EXCEPTION_DATATYPE_MISALIGNMENT;
1173         break;
1174     default:
1175         WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
1176         /* fall through */
1177     case TRAP_x86_NMI:       /* NMI interrupt */
1178     case TRAP_x86_DNA:       /* Device not available exception */
1179     case TRAP_x86_DOUBLEFLT: /* Double fault exception */
1180     case TRAP_x86_TSSFLT:    /* Invalid TSS exception */
1181     case TRAP_x86_MCHK:      /* Machine check exception */
1182     case TRAP_x86_CACHEFLT:  /* Cache flush exception */
1183         rec->ExceptionCode = EXCEPTION_ILLEGAL_INSTRUCTION;
1184         break;
1185     }
1186 }
1187
1188
1189 /**********************************************************************
1190  *              trap_handler
1191  *
1192  * Handler for SIGTRAP.
1193  */
1194 static void trap_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1195 {
1196     SIGCONTEXT *context = sigcontext;
1197     EXCEPTION_RECORD *rec = setup_exception( context, raise_trap_exception );
1198
1199     switch(get_trap_code(context))
1200     {
1201     case TRAP_x86_TRCTRAP:  /* Single-step exception */
1202         rec->ExceptionCode = EXCEPTION_SINGLE_STEP;
1203         break;
1204     case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1205         rec->ExceptionAddress = (char *)rec->ExceptionAddress - 1;  /* back up over the int3 instruction */
1206         /* fall through */
1207     default:
1208         rec->ExceptionCode = EXCEPTION_BREAKPOINT;
1209         break;
1210     }
1211 }
1212
1213
1214 /**********************************************************************
1215  *              fpe_handler
1216  *
1217  * Handler for SIGFPE.
1218  */
1219 static void fpe_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1220 {
1221     CONTEXT *win_context;
1222     SIGCONTEXT *context = sigcontext;
1223     EXCEPTION_RECORD *rec = setup_exception( context, raise_exception );
1224
1225     win_context = get_exception_context( rec );
1226
1227     switch(get_trap_code(context))
1228     {
1229     case TRAP_x86_DIVIDE:   /* Division by zero exception */
1230         rec->ExceptionCode = EXCEPTION_INT_DIVIDE_BY_ZERO;
1231         break;
1232     case TRAP_x86_FPOPFLT:   /* Coprocessor segment overrun */
1233         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1234         break;
1235     case TRAP_x86_ARITHTRAP:  /* Floating point exception */
1236     case TRAP_x86_UNKNOWN:    /* Unknown fault code */
1237         rec->ExceptionCode = get_fpu_code( win_context );
1238         break;
1239     case TRAP_x86_CACHEFLT:  /* SIMD exception */
1240         /* TODO:
1241          * Behaviour only tested for divide-by-zero exceptions
1242          * Check for other SIMD exceptions as well */
1243         if(siginfo->si_code != FPE_FLTDIV)
1244             FIXME("untested SIMD exception: %#x. Might not work correctly\n",
1245                   siginfo->si_code);
1246
1247         rec->ExceptionCode = STATUS_FLOAT_MULTIPLE_TRAPS;
1248         rec->NumberParameters = 1;
1249         /* no idea what meaning is actually behind this but that's what native does */
1250         rec->ExceptionInformation[0] = 0;
1251         break;
1252     default:
1253         WINE_ERR( "Got unexpected trap %d\n", get_trap_code(context) );
1254         rec->ExceptionCode = EXCEPTION_FLT_INVALID_OPERATION;
1255         break;
1256     }
1257 }
1258
1259
1260 /**********************************************************************
1261  *              int_handler
1262  *
1263  * Handler for SIGINT.
1264  *
1265  * FIXME: should not be calling external functions on the signal stack.
1266  */
1267 static void int_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1268 {
1269     WORD fs, gs;
1270     init_handler( sigcontext, &fs, &gs );
1271     if (!dispatch_signal(SIGINT))
1272     {
1273         EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_exception );
1274         rec->ExceptionCode = CONTROL_C_EXIT;
1275     }
1276 }
1277
1278 /**********************************************************************
1279  *              abrt_handler
1280  *
1281  * Handler for SIGABRT.
1282  */
1283 static void abrt_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1284 {
1285     EXCEPTION_RECORD *rec = setup_exception( sigcontext, raise_exception );
1286     rec->ExceptionCode  = EXCEPTION_WINE_ASSERTION;
1287     rec->ExceptionFlags = EH_NONCONTINUABLE;
1288 }
1289
1290
1291 /**********************************************************************
1292  *              term_handler
1293  *
1294  * Handler for SIGTERM.
1295  */
1296 static void term_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1297 {
1298     WORD fs, gs;
1299     init_handler( sigcontext, &fs, &gs );
1300     server_abort_thread(0);
1301 }
1302
1303
1304 /**********************************************************************
1305  *              usr1_handler
1306  *
1307  * Handler for SIGUSR1, used to signal a thread that it got suspended.
1308  */
1309 static void usr1_handler( int signal, siginfo_t *siginfo, void *sigcontext )
1310 {
1311     CONTEXT context;
1312     WORD fs, gs;
1313
1314     init_handler( sigcontext, &fs, &gs );
1315     save_context( &context, sigcontext, fs, gs );
1316     wait_suspend( &context );
1317     restore_context( &context, sigcontext );
1318 }
1319
1320
1321 /**********************************************************************
1322  *              get_signal_stack_total_size
1323  *
1324  * Retrieve the size to allocate for the signal stack, including the TEB at the bottom.
1325  * Must be a power of two.
1326  */
1327 size_t get_signal_stack_total_size(void)
1328 {
1329     static const size_t teb_size = 4096;  /* we reserve one page for the TEB */
1330
1331     if (!signal_stack_size)
1332     {
1333         size_t size = 8192, min_size = teb_size + max( MINSIGSTKSZ, 8192 );
1334         /* find the first power of two not smaller than min_size */
1335         while (size < min_size) size *= 2;
1336         signal_stack_mask = size - 1;
1337         signal_stack_size = size - teb_size;
1338     }
1339     return signal_stack_size + teb_size;
1340 }
1341
1342
1343 /***********************************************************************
1344  *           __wine_set_signal_handler   (NTDLL.@)
1345  */
1346 int __wine_set_signal_handler(unsigned int sig, wine_signal_handler wsh)
1347 {
1348     if (sig >= sizeof(handlers) / sizeof(handlers[0])) return -1;
1349     if (handlers[sig] != NULL) return -2;
1350     handlers[sig] = wsh;
1351     return 0;
1352 }
1353
1354
1355 /**********************************************************************
1356  *              SIGNAL_Init
1357  */
1358 BOOL SIGNAL_Init(void)
1359 {
1360     struct sigaction sig_act;
1361
1362 #ifdef HAVE_SIGALTSTACK
1363     stack_t ss;
1364
1365 #ifdef __APPLE__
1366     int mib[2], val = 1;
1367
1368     mib[0] = CTL_KERN;
1369     mib[1] = KERN_THALTSTACK;
1370     sysctl( mib, 2, NULL, NULL, &val, sizeof(val) );
1371 #endif
1372
1373     ss.ss_sp    = get_signal_stack();
1374     ss.ss_size  = signal_stack_size;
1375     ss.ss_flags = 0;
1376     if (sigaltstack(&ss, NULL) == -1)
1377     {
1378         perror( "sigaltstack" );
1379         return FALSE;
1380     }
1381 #endif  /* HAVE_SIGALTSTACK */
1382
1383     sig_act.sa_mask = server_block_set;
1384     sig_act.sa_flags = SA_SIGINFO | SA_RESTART;
1385 #ifdef SA_ONSTACK
1386     sig_act.sa_flags |= SA_ONSTACK;
1387 #endif
1388
1389     sig_act.sa_sigaction = int_handler;
1390     if (sigaction( SIGINT, &sig_act, NULL ) == -1) goto error;
1391     sig_act.sa_sigaction = fpe_handler;
1392     if (sigaction( SIGFPE, &sig_act, NULL ) == -1) goto error;
1393     sig_act.sa_sigaction = abrt_handler;
1394     if (sigaction( SIGABRT, &sig_act, NULL ) == -1) goto error;
1395     sig_act.sa_sigaction = term_handler;
1396     if (sigaction( SIGTERM, &sig_act, NULL ) == -1) goto error;
1397     sig_act.sa_sigaction = usr1_handler;
1398     if (sigaction( SIGUSR1, &sig_act, NULL ) == -1) goto error;
1399
1400     sig_act.sa_sigaction = segv_handler;
1401     if (sigaction( SIGSEGV, &sig_act, NULL ) == -1) goto error;
1402     if (sigaction( SIGILL, &sig_act, NULL ) == -1) goto error;
1403 #ifdef SIGBUS
1404     if (sigaction( SIGBUS, &sig_act, NULL ) == -1) goto error;
1405 #endif
1406
1407 #ifdef SIGTRAP
1408     sig_act.sa_sigaction = trap_handler;
1409     if (sigaction( SIGTRAP, &sig_act, NULL ) == -1) goto error;
1410 #endif
1411
1412 #ifdef __HAVE_VM86
1413     sig_act.sa_sigaction = usr2_handler;
1414     if (sigaction( SIGUSR2, &sig_act, NULL ) == -1) goto error;
1415 #endif
1416
1417     return TRUE;
1418
1419  error:
1420     perror("sigaction");
1421     return FALSE;
1422 }
1423
1424
1425 #ifdef __HAVE_VM86
1426 /**********************************************************************
1427  *              __wine_enter_vm86   (NTDLL.@)
1428  *
1429  * Enter vm86 mode with the specified register context.
1430  */
1431 void __wine_enter_vm86( CONTEXT *context )
1432 {
1433     EXCEPTION_RECORD rec;
1434     int res;
1435     struct vm86plus_struct vm86;
1436
1437     memset( &vm86, 0, sizeof(vm86) );
1438     for (;;)
1439     {
1440         restore_vm86_context( context, &vm86 );
1441
1442         ntdll_get_thread_data()->vm86_ptr = &vm86;
1443         merge_vm86_pending_flags( &rec );
1444
1445         res = vm86_enter( &ntdll_get_thread_data()->vm86_ptr ); /* uses and clears teb->vm86_ptr */
1446         if (res < 0)
1447         {
1448             errno = -res;
1449             return;
1450         }
1451
1452         save_vm86_context( context, &vm86 );
1453
1454         rec.ExceptionFlags   = EXCEPTION_CONTINUABLE;
1455         rec.ExceptionRecord  = NULL;
1456         rec.ExceptionAddress = (LPVOID)context->Eip;
1457         rec.NumberParameters = 0;
1458
1459         switch(VM86_TYPE(res))
1460         {
1461         case VM86_UNKNOWN: /* unhandled GP fault - IO-instruction or similar */
1462             rec.ExceptionCode = EXCEPTION_PRIV_INSTRUCTION;
1463             break;
1464         case VM86_TRAP: /* return due to DOS-debugger request */
1465             switch(VM86_ARG(res))
1466             {
1467             case TRAP_x86_TRCTRAP:  /* Single-step exception */
1468                 rec.ExceptionCode = EXCEPTION_SINGLE_STEP;
1469                 break;
1470             case TRAP_x86_BPTFLT:   /* Breakpoint exception */
1471                 rec.ExceptionAddress = (char *)rec.ExceptionAddress - 1;  /* back up over the int3 instruction */
1472                 /* fall through */
1473             default:
1474                 rec.ExceptionCode = EXCEPTION_BREAKPOINT;
1475                 break;
1476             }
1477             break;
1478         case VM86_INTx: /* int3/int x instruction (ARG = x) */
1479             rec.ExceptionCode = EXCEPTION_VM86_INTx;
1480             rec.NumberParameters = 1;
1481             rec.ExceptionInformation[0] = VM86_ARG(res);
1482             break;
1483         case VM86_STI: /* sti/popf/iret instruction enabled virtual interrupts */
1484             context->EFlags |= VIF_MASK;
1485             context->EFlags &= ~VIP_MASK;
1486             NtCurrentTeb()->vm86_pending = 0;
1487             rec.ExceptionCode = EXCEPTION_VM86_STI;
1488             break;
1489         case VM86_PICRETURN: /* return due to pending PIC request */
1490             rec.ExceptionCode = EXCEPTION_VM86_PICRETURN;
1491             break;
1492         case VM86_SIGNAL: /* cannot happen because vm86_enter handles this case */
1493         default:
1494             WINE_ERR( "unhandled result from vm86 mode %x\n", res );
1495             continue;
1496         }
1497         __regs_RtlRaiseException( &rec, context );
1498     }
1499 }
1500
1501 #else /* __HAVE_VM86 */
1502 /**********************************************************************
1503  *              __wine_enter_vm86   (NTDLL.@)
1504  */
1505 void __wine_enter_vm86( CONTEXT *context )
1506 {
1507     MESSAGE("vm86 mode not supported on this platform\n");
1508 }
1509 #endif /* __HAVE_VM86 */
1510
1511 /**********************************************************************
1512  *              DbgBreakPoint   (NTDLL.@)
1513  */
1514 __ASM_GLOBAL_FUNC( DbgBreakPoint, "int $3; ret")
1515
1516 /**********************************************************************
1517  *              DbgUserBreakPoint   (NTDLL.@)
1518  */
1519 __ASM_GLOBAL_FUNC( DbgUserBreakPoint, "int $3; ret")
1520
1521
1522 /**********************************************************************
1523  *              EXC_CallHandler   (internal)
1524  *
1525  * Some exception handlers depend on EBP to have a fixed position relative to
1526  * the exception frame.
1527  * Shrinker depends on (*1) doing what it does,
1528  * (*2) being the exact instruction it is and (*3) beginning with 0x64
1529  * (i.e. the %fs prefix to the movl instruction). It also depends on the
1530  * function calling the handler having only 5 parameters (*4).
1531  */
1532 __ASM_GLOBAL_FUNC( EXC_CallHandler,
1533 "       pushl   %ebp\n"
1534 "       movl    %esp, %ebp\n"
1535 "       pushl   %ebx\n"
1536 "       movl    28(%ebp), %edx\n" /* ugly hack to pass the 6th param needed because of Shrinker */
1537 "       pushl   24(%ebp)\n"
1538 "       pushl   20(%ebp)\n"
1539 "       pushl   16(%ebp)\n"
1540 "       pushl   12(%ebp)\n"
1541 "       pushl   8(%ebp)\n"
1542 "       call    " __ASM_NAME("call_exception_handler") "\n"
1543 "       popl    %ebx\n"
1544 "       leave\n"
1545 "       ret\n"
1546 )
1547 __ASM_GLOBAL_FUNC(call_exception_handler,
1548 "       pushl   %ebp\n"
1549 "       movl    %esp, %ebp\n"
1550 "       subl    $12,%esp\n"
1551 "       pushl   12(%ebp)\n"       /* make any exceptions in this... */
1552 "       pushl   %edx\n"           /* handler be handled by... */
1553 "       .byte   0x64\n"
1554 "       pushl   (0)\n"            /* nested_handler (passed in edx). */
1555 "       .byte   0x64\n"
1556 "       movl    %esp,(0)\n"       /* push the new exception frame onto the exception stack. */
1557 "       pushl   20(%ebp)\n"
1558 "       pushl   16(%ebp)\n"
1559 "       pushl   12(%ebp)\n"
1560 "       pushl   8(%ebp)\n"
1561 "       movl    24(%ebp), %ecx\n" /* (*1) */
1562 "       call    *%ecx\n"          /* call handler. (*2) */
1563 "       .byte   0x64\n"
1564 "       movl    (0), %esp\n"      /* restore previous... (*3) */
1565 "       .byte   0x64\n"
1566 "       popl    (0)\n"            /* exception frame. */
1567 "       movl    %ebp, %esp\n"     /* restore saved stack, in case it was corrupted */
1568 "       popl    %ebp\n"
1569 "       ret     $20\n"            /* (*4) */
1570 )
1571 #endif  /* __i386__ */