dlls/ntdll/exception.c

   1 /*
   2  * NT exception handling routines
   3  *
   4  * Copyright 1999 Turchanov Sergey
   5  * Copyright 1999 Alexandre Julliard
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "config.h"
  23 #include "wine/port.h"
  24
  25 #include <assert.h>
  26 #include <errno.h>
  27 #include <signal.h>
  28 #include <stdarg.h>
  29
  30 #include "ntstatus.h"
  31 #define WIN32_NO_STATUS
  32 #include "windef.h"
  33 #include "winternl.h"
  34 #include "wine/exception.h"
  35 #include "wine/server.h"
  36 #include "wine/list.h"
  37 #include "wine/debug.h"
  38 #include "excpt.h"
  39 #include "ntdll_misc.h"
  40
  41 WINE_DEFAULT_DEBUG_CHANNEL(seh);
  42
  43 typedef struct
  44 {
  45     struct list                 entry;
  46     PVECTORED_EXCEPTION_HANDLER func;
  47     ULONG                       count;
  48 } VECTORED_HANDLER;
  49
  50 static struct list vectored_handlers = LIST_INIT(vectored_handlers);
  51
  52 static RTL_CRITICAL_SECTION vectored_handlers_section;
  53 static RTL_CRITICAL_SECTION_DEBUG critsect_debug =
  54 {
  55     0, 0, &vectored_handlers_section,
  56     { &critsect_debug.ProcessLocksList, &critsect_debug.ProcessLocksList },
  57       0, 0, { (DWORD_PTR)(__FILE__ ": vectored_handlers_section") }
  58 };
  59 static RTL_CRITICAL_SECTION vectored_handlers_section = { &critsect_debug, -1, 0, 0, 0, 0 };
  60
  61 /**********************************************************************
  62  *           wait_suspend
  63  *
  64  * Wait until the thread is no longer suspended.
  65  */
  66 void wait_suspend( CONTEXT *context )
  67 {
  68     LARGE_INTEGER timeout;
  69     int saved_errno = errno;
  70     context_t server_context;
  71
  72     context_to_server( &server_context, context );
  73
  74     /* store the context we got at suspend time */
  75     SERVER_START_REQ( set_suspend_context )
  76     {
  77         wine_server_add_data( req, &server_context, sizeof(server_context) );
  78         wine_server_call( req );
  79     }
  80     SERVER_END_REQ;
  81
  82     /* wait with 0 timeout, will only return once the thread is no longer suspended */
  83     timeout.QuadPart = 0;
  84     NTDLL_wait_for_multiple_objects( 0, NULL, SELECT_INTERRUPTIBLE, &timeout, 0 );
  85
  86     /* retrieve the new context */
  87     SERVER_START_REQ( get_suspend_context )
  88     {
  89         wine_server_set_reply( req, &server_context, sizeof(server_context) );
  90         wine_server_call( req );
  91     }
  92     SERVER_END_REQ;
  93
  94     context_from_server( context, &server_context );
  95     errno = saved_errno;
  96 }
  97
  98
  99 /**********************************************************************
 100  *           send_debug_event
 101  *
 102  * Send an EXCEPTION_DEBUG_EVENT event to the debugger.
 103  */
 104 NTSTATUS send_debug_event( EXCEPTION_RECORD *rec, int first_chance, CONTEXT *context )
 105 {
 106     NTSTATUS ret;
 107     DWORD i;
 108     HANDLE handle = 0;
 109     client_ptr_t params[EXCEPTION_MAXIMUM_PARAMETERS];
 110     context_t server_context;
 111
 112     if (!NtCurrentTeb()->Peb->BeingDebugged) return 0;  /* no debugger present */
 113
 114     for (i = 0; i < min( rec->NumberParameters, EXCEPTION_MAXIMUM_PARAMETERS ); i++)
 115         params[i] = rec->ExceptionInformation[i];
 116
 117     context_to_server( &server_context, context );
 118
 119     SERVER_START_REQ( queue_exception_event )
 120     {
 121         req->first   = first_chance;
 122         req->code    = rec->ExceptionCode;
 123         req->flags   = rec->ExceptionFlags;
 124         req->record  = wine_server_client_ptr( rec->ExceptionRecord );
 125         req->address = wine_server_client_ptr( rec->ExceptionAddress );
 126         req->len     = i * sizeof(params[0]);
 127         wine_server_add_data( req, params, req->len );
 128         wine_server_add_data( req, &server_context, sizeof(server_context) );
 129         if (!wine_server_call( req )) handle = wine_server_ptr_handle( reply->handle );
 130     }
 131     SERVER_END_REQ;
 132     if (!handle) return 0;
 133
 134     NTDLL_wait_for_multiple_objects( 1, &handle, SELECT_INTERRUPTIBLE, NULL, 0 );
 135
 136     SERVER_START_REQ( get_exception_status )
 137     {
 138         req->handle = wine_server_obj_handle( handle );
 139         wine_server_set_reply( req, &server_context, sizeof(server_context) );
 140         ret = wine_server_call( req );
 141     }
 142     SERVER_END_REQ;
 143     if (ret >= 0) context_from_server( context, &server_context );
 144     return ret;
 145 }
 146
 147
 148 /**********************************************************************
 149  *           call_vectored_handlers
 150  *
 151  * Call the vectored handlers chain.
 152  */
 153 LONG call_vectored_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 154 {
 155     struct list *ptr;
 156     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 157     EXCEPTION_POINTERS except_ptrs;
 158     PVECTORED_EXCEPTION_HANDLER func;
 159     VECTORED_HANDLER *handler, *to_free = NULL;
 160
 161     except_ptrs.ExceptionRecord = rec;
 162     except_ptrs.ContextRecord = context;
 163
 164     RtlEnterCriticalSection( &vectored_handlers_section );
 165     ptr = list_head( &vectored_handlers );
 166     while (ptr)
 167     {
 168         handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 169         handler->count++;
 170         func = RtlDecodePointer( handler->func );
 171         RtlLeaveCriticalSection( &vectored_handlers_section );
 172         RtlFreeHeap( GetProcessHeap(), 0, to_free );
 173         to_free = NULL;
 174
 175         TRACE( "calling handler at %p code=%x flags=%x\n",
 176                func, rec->ExceptionCode, rec->ExceptionFlags );
 177         ret = func( &except_ptrs );
 178         TRACE( "handler at %p returned %x\n", func, ret );
 179
 180         RtlEnterCriticalSection( &vectored_handlers_section );
 181         ptr = list_next( &vectored_handlers, ptr );
 182         if (!--handler->count)  /* removed during execution */
 183         {
 184             list_remove( &handler->entry );
 185             to_free = handler;
 186         }
 187         if (ret == EXCEPTION_CONTINUE_EXECUTION) break;
 188     }
 189     RtlLeaveCriticalSection( &vectored_handlers_section );
 190     RtlFreeHeap( GetProcessHeap(), 0, to_free );
 191     return ret;
 192 }
 193
 194
 195 /*******************************************************************
 196  *              raise_status
 197  *
 198  * Implementation of RtlRaiseStatus with a specific exception record.
 199  */
 200 void raise_status( NTSTATUS status, EXCEPTION_RECORD *rec )
 201 {
 202     EXCEPTION_RECORD ExceptionRec;
 203
 204     ExceptionRec.ExceptionCode    = status;
 205     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 206     ExceptionRec.ExceptionRecord  = rec;
 207     ExceptionRec.NumberParameters = 0;
 208     for (;;) RtlRaiseException( &ExceptionRec );  /* never returns */
 209 }
 210
 211
 212 /***********************************************************************
 213  *            RtlRaiseStatus  (NTDLL.@)
 214  *
 215  * Raise an exception with ExceptionCode = status
 216  */
 217 void WINAPI RtlRaiseStatus( NTSTATUS status )
 218 {
 219     raise_status( status, NULL );
 220 }
 221
 222
 223 /*******************************************************************
 224  *         RtlAddVectoredExceptionHandler   (NTDLL.@)
 225  */
 226 PVOID WINAPI RtlAddVectoredExceptionHandler( ULONG first, PVECTORED_EXCEPTION_HANDLER func )
 227 {
 228     VECTORED_HANDLER *handler = RtlAllocateHeap( GetProcessHeap(), 0, sizeof(*handler) );
 229     if (handler)
 230     {
 231         handler->func = RtlEncodePointer( func );
 232         handler->count = 1;
 233         RtlEnterCriticalSection( &vectored_handlers_section );
 234         if (first) list_add_head( &vectored_handlers, &handler->entry );
 235         else list_add_tail( &vectored_handlers, &handler->entry );
 236         RtlLeaveCriticalSection( &vectored_handlers_section );
 237     }
 238     return handler;
 239 }
 240
 241
 242 /*******************************************************************
 243  *         RtlRemoveVectoredExceptionHandler   (NTDLL.@)
 244  */
 245 ULONG WINAPI RtlRemoveVectoredExceptionHandler( PVOID handler )
 246 {
 247     struct list *ptr;
 248     ULONG ret = FALSE;
 249
 250     RtlEnterCriticalSection( &vectored_handlers_section );
 251     LIST_FOR_EACH( ptr, &vectored_handlers )
 252     {
 253         VECTORED_HANDLER *curr_handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 254         if (curr_handler == handler)
 255         {
 256             if (!--curr_handler->count) list_remove( ptr );
 257             else handler = NULL;  /* don't free it yet */
 258             ret = TRUE;
 259             break;
 260         }
 261     }
 262     RtlLeaveCriticalSection( &vectored_handlers_section );
 263     if (ret) RtlFreeHeap( GetProcessHeap(), 0, handler );
 264     return ret;
 265 }
 266
 267
 268 /*************************************************************
 269  *            __wine_spec_unimplemented_stub
 270  *
 271  * ntdll-specific implementation to avoid depending on kernel functions.
 272  * Can be removed once ntdll.spec no longer contains stubs.
 273  */
 274 void __wine_spec_unimplemented_stub( const char *module, const char *function )
 275 {
 276     EXCEPTION_RECORD record;
 277
 278     record.ExceptionCode    = EXCEPTION_WINE_STUB;
 279     record.ExceptionFlags   = EH_NONCONTINUABLE;
 280     record.ExceptionRecord  = NULL;
 281     record.ExceptionAddress = __wine_spec_unimplemented_stub;
 282     record.NumberParameters = 2;
 283     record.ExceptionInformation[0] = (ULONG_PTR)module;
 284     record.ExceptionInformation[1] = (ULONG_PTR)function;
 285     for (;;) RtlRaiseException( &record );
 286 }