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     server_select( NULL, 0, SELECT_INTERRUPTIBLE, &timeout );
  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     obj_handle_t handle = 0;
 109     client_ptr_t params[EXCEPTION_MAXIMUM_PARAMETERS];
 110     context_t server_context;
 111     select_op_t select_op;
 112
 113     if (!NtCurrentTeb()->Peb->BeingDebugged) return 0;  /* no debugger present */
 114
 115     for (i = 0; i < min( rec->NumberParameters, EXCEPTION_MAXIMUM_PARAMETERS ); i++)
 116         params[i] = rec->ExceptionInformation[i];
 117
 118     context_to_server( &server_context, context );
 119
 120     SERVER_START_REQ( queue_exception_event )
 121     {
 122         req->first   = first_chance;
 123         req->code    = rec->ExceptionCode;
 124         req->flags   = rec->ExceptionFlags;
 125         req->record  = wine_server_client_ptr( rec->ExceptionRecord );
 126         req->address = wine_server_client_ptr( rec->ExceptionAddress );
 127         req->len     = i * sizeof(params[0]);
 128         wine_server_add_data( req, params, req->len );
 129         wine_server_add_data( req, &server_context, sizeof(server_context) );
 130         if (!wine_server_call( req )) handle = reply->handle;
 131     }
 132     SERVER_END_REQ;
 133     if (!handle) return 0;
 134
 135     select_op.wait.op = SELECT_WAIT;
 136     select_op.wait.handles[0] = handle;
 137     server_select( &select_op, offsetof( select_op_t, wait.handles[1] ), SELECT_INTERRUPTIBLE, NULL );
 138
 139     SERVER_START_REQ( get_exception_status )
 140     {
 141         req->handle = handle;
 142         wine_server_set_reply( req, &server_context, sizeof(server_context) );
 143         ret = wine_server_call( req );
 144     }
 145     SERVER_END_REQ;
 146     if (ret >= 0) context_from_server( context, &server_context );
 147     return ret;
 148 }
 149
 150
 151 /**********************************************************************
 152  *           call_vectored_handlers
 153  *
 154  * Call the vectored handlers chain.
 155  */
 156 LONG call_vectored_handlers( EXCEPTION_RECORD *rec, CONTEXT *context )
 157 {
 158     struct list *ptr;
 159     LONG ret = EXCEPTION_CONTINUE_SEARCH;
 160     EXCEPTION_POINTERS except_ptrs;
 161     PVECTORED_EXCEPTION_HANDLER func;
 162     VECTORED_HANDLER *handler, *to_free = NULL;
 163
 164     except_ptrs.ExceptionRecord = rec;
 165     except_ptrs.ContextRecord = context;
 166
 167     RtlEnterCriticalSection( &vectored_handlers_section );
 168     ptr = list_head( &vectored_handlers );
 169     while (ptr)
 170     {
 171         handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 172         handler->count++;
 173         func = RtlDecodePointer( handler->func );
 174         RtlLeaveCriticalSection( &vectored_handlers_section );
 175         RtlFreeHeap( GetProcessHeap(), 0, to_free );
 176         to_free = NULL;
 177
 178         TRACE( "calling handler at %p code=%x flags=%x\n",
 179                func, rec->ExceptionCode, rec->ExceptionFlags );
 180         ret = func( &except_ptrs );
 181         TRACE( "handler at %p returned %x\n", func, ret );
 182
 183         RtlEnterCriticalSection( &vectored_handlers_section );
 184         ptr = list_next( &vectored_handlers, ptr );
 185         if (!--handler->count)  /* removed during execution */
 186         {
 187             list_remove( &handler->entry );
 188             to_free = handler;
 189         }
 190         if (ret == EXCEPTION_CONTINUE_EXECUTION) break;
 191     }
 192     RtlLeaveCriticalSection( &vectored_handlers_section );
 193     RtlFreeHeap( GetProcessHeap(), 0, to_free );
 194     return ret;
 195 }
 196
 197
 198 /*******************************************************************
 199  *              raise_status
 200  *
 201  * Implementation of RtlRaiseStatus with a specific exception record.
 202  */
 203 void raise_status( NTSTATUS status, EXCEPTION_RECORD *rec )
 204 {
 205     EXCEPTION_RECORD ExceptionRec;
 206
 207     ExceptionRec.ExceptionCode    = status;
 208     ExceptionRec.ExceptionFlags   = EH_NONCONTINUABLE;
 209     ExceptionRec.ExceptionRecord  = rec;
 210     ExceptionRec.NumberParameters = 0;
 211     for (;;) RtlRaiseException( &ExceptionRec );  /* never returns */
 212 }
 213
 214
 215 /***********************************************************************
 216  *            RtlRaiseStatus  (NTDLL.@)
 217  *
 218  * Raise an exception with ExceptionCode = status
 219  */
 220 void WINAPI RtlRaiseStatus( NTSTATUS status )
 221 {
 222     raise_status( status, NULL );
 223 }
 224
 225
 226 /*******************************************************************
 227  *         RtlAddVectoredExceptionHandler   (NTDLL.@)
 228  */
 229 PVOID WINAPI RtlAddVectoredExceptionHandler( ULONG first, PVECTORED_EXCEPTION_HANDLER func )
 230 {
 231     VECTORED_HANDLER *handler = RtlAllocateHeap( GetProcessHeap(), 0, sizeof(*handler) );
 232     if (handler)
 233     {
 234         handler->func = RtlEncodePointer( func );
 235         handler->count = 1;
 236         RtlEnterCriticalSection( &vectored_handlers_section );
 237         if (first) list_add_head( &vectored_handlers, &handler->entry );
 238         else list_add_tail( &vectored_handlers, &handler->entry );
 239         RtlLeaveCriticalSection( &vectored_handlers_section );
 240     }
 241     return handler;
 242 }
 243
 244
 245 /*******************************************************************
 246  *         RtlRemoveVectoredExceptionHandler   (NTDLL.@)
 247  */
 248 ULONG WINAPI RtlRemoveVectoredExceptionHandler( PVOID handler )
 249 {
 250     struct list *ptr;
 251     ULONG ret = FALSE;
 252
 253     RtlEnterCriticalSection( &vectored_handlers_section );
 254     LIST_FOR_EACH( ptr, &vectored_handlers )
 255     {
 256         VECTORED_HANDLER *curr_handler = LIST_ENTRY( ptr, VECTORED_HANDLER, entry );
 257         if (curr_handler == handler)
 258         {
 259             if (!--curr_handler->count) list_remove( ptr );
 260             else handler = NULL;  /* don't free it yet */
 261             ret = TRUE;
 262             break;
 263         }
 264     }
 265     RtlLeaveCriticalSection( &vectored_handlers_section );
 266     if (ret) RtlFreeHeap( GetProcessHeap(), 0, handler );
 267     return ret;
 268 }
 269
 270
 271 /*************************************************************
 272  *            __wine_spec_unimplemented_stub
 273  *
 274  * ntdll-specific implementation to avoid depending on kernel functions.
 275  * Can be removed once ntdll.spec no longer contains stubs.
 276  */
 277 void __wine_spec_unimplemented_stub( const char *module, const char *function )
 278 {
 279     EXCEPTION_RECORD record;
 280
 281     record.ExceptionCode    = EXCEPTION_WINE_STUB;
 282     record.ExceptionFlags   = EH_NONCONTINUABLE;
 283     record.ExceptionRecord  = NULL;
 284     record.ExceptionAddress = __wine_spec_unimplemented_stub;
 285     record.NumberParameters = 2;
 286     record.ExceptionInformation[0] = (ULONG_PTR)module;
 287     record.ExceptionInformation[1] = (ULONG_PTR)function;
 288     for (;;) RtlRaiseException( &record );
 289 }