dlls/winhttp/handle.c

   1 /*
   2  * Copyright 2008 Hans Leidekker for CodeWeavers
   3  *
   4  * Based on the handle implementation from wininet.
   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 #include <stdarg.h>
  22
  23 #include "windef.h"
  24 #include "winbase.h"
  25 #include "ws2tcpip.h"
  26 #include "winhttp.h"
  27
  28 #include "wine/debug.h"
  29 #include "winhttp_private.h"
  30
  31 WINE_DEFAULT_DEBUG_CHANNEL(winhttp);
  32
  33 #define HANDLE_CHUNK_SIZE 0x10
  34
  35 static CRITICAL_SECTION handle_cs;
  36 static CRITICAL_SECTION_DEBUG handle_cs_debug =
  37 {
  38     0, 0, &handle_cs,
  39     { &handle_cs_debug.ProcessLocksList, &handle_cs_debug.ProcessLocksList },
  40       0, 0, { (ULONG_PTR)(__FILE__ ": handle_cs") }
  41 };
  42 static CRITICAL_SECTION handle_cs = { &handle_cs_debug, -1, 0, 0, 0, 0 };
  43
  44 static struct object_header **handles;
  45 static ULONG_PTR next_handle;
  46 static ULONG_PTR max_handles;
  47
  48 struct object_header *addref_object( struct object_header *hdr )
  49 {
  50     ULONG refs = InterlockedIncrement( &hdr->refs );
  51     TRACE( "%p -> refcount = %lu\n", hdr, refs );
  52     return hdr;
  53 }
  54
  55 struct object_header *grab_object( HINTERNET hinternet )
  56 {
  57     struct object_header *hdr = NULL;
  58     ULONG_PTR handle = (ULONG_PTR)hinternet;
  59
  60     EnterCriticalSection( &handle_cs );
  61
  62     if ((handle > 0) && (handle <= max_handles) && handles[handle - 1])
  63         hdr = addref_object( handles[handle - 1] );
  64
  65     LeaveCriticalSection( &handle_cs );
  66
  67     TRACE( "handle %Ix -> %p\n", handle, hdr );
  68     return hdr;
  69 }
  70
  71 void release_object( struct object_header *hdr )
  72 {
  73     ULONG refs = InterlockedDecrement( &hdr->refs );
  74     TRACE( "object %p refcount = %lu\n", hdr, refs );
  75     if (!refs)
  76     {
  77         if (hdr->type == WINHTTP_HANDLE_TYPE_REQUEST) close_connection( (struct request *)hdr );
  78
  79         send_callback( hdr, WINHTTP_CALLBACK_STATUS_HANDLE_CLOSING, &hdr->handle, sizeof(HINTERNET) );
  80
  81         TRACE( "destroying object %p\n", hdr );
  82         hdr->vtbl->destroy( hdr );
  83     }
  84 }
  85
  86 HINTERNET alloc_handle( struct object_header *hdr )
  87 {
  88     struct object_header **p;
  89     ULONG_PTR handle, num;
  90
  91     hdr->handle = NULL;
  92
  93     EnterCriticalSection( &handle_cs );
  94     if (!max_handles)
  95     {
  96         num = HANDLE_CHUNK_SIZE;
  97         if (!(p = calloc( 1, sizeof(ULONG_PTR) * num ))) goto end;
  98         handles = p;
  99         max_handles = num;
 100     }
 101     if (max_handles == next_handle)
 102     {
 103         size_t new_size, old_size = max_handles * sizeof(ULONG_PTR);
 104         num = max_handles * 2;
 105         new_size = num * sizeof(ULONG_PTR);
 106         if (!(p = realloc( handles, new_size ))) goto end;
 107         memset( (char *)p + old_size, 0, new_size - old_size );
 108         handles = p;
 109         max_handles = num;
 110     }
 111     handle = next_handle;
 112     if (handles[handle]) ERR("handle isn't free but should be\n");
 113
 114     handles[handle] = addref_object( hdr );
 115     hdr->handle = (HINTERNET)(handle + 1);
 116     while ((next_handle < max_handles) && handles[next_handle]) next_handle++;
 117
 118 end:
 119     LeaveCriticalSection( &handle_cs );
 120     return hdr->handle;
 121 }
 122
 123 BOOL free_handle( HINTERNET hinternet )
 124 {
 125     BOOL ret = FALSE;
 126     ULONG_PTR handle = (ULONG_PTR)hinternet;
 127     struct object_header *hdr = NULL;
 128
 129     EnterCriticalSection( &handle_cs );
 130
 131     if ((handle > 0) && (handle <= max_handles))
 132     {
 133         handle--;
 134         if (handles[handle])
 135         {
 136             hdr = handles[handle];
 137             TRACE( "destroying handle %Ix for object %p\n", handle + 1, hdr );
 138             handles[handle] = NULL;
 139             ret = TRUE;
 140         }
 141     }
 142
 143     LeaveCriticalSection( &handle_cs );
 144
 145     if (hdr) release_object( hdr );
 146
 147     EnterCriticalSection( &handle_cs );
 148     if (next_handle > handle && !handles[handle]) next_handle = handle;
 149     LeaveCriticalSection( &handle_cs );
 150
 151     return ret;
 152 }