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 = %d\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 0x%lx -> %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 = %d\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 = heap_alloc_zero( sizeof(ULONG_PTR) * num ))) goto end;
  98         handles = p;
  99         max_handles = num;
 100     }
 101     if (max_handles == next_handle)
 102     {
 103         num = max_handles * 2;
 104         if (!(p = heap_realloc_zero( handles, sizeof(ULONG_PTR) * num ))) goto end;
 105         handles = p;
 106         max_handles = num;
 107     }
 108     handle = next_handle;
 109     if (handles[handle]) ERR("handle isn't free but should be\n");
 110
 111     handles[handle] = addref_object( hdr );
 112     hdr->handle = (HINTERNET)(handle + 1);
 113     while ((next_handle < max_handles) && handles[next_handle]) next_handle++;
 114
 115 end:
 116     LeaveCriticalSection( &handle_cs );
 117     return hdr->handle;
 118 }
 119
 120 BOOL free_handle( HINTERNET hinternet )
 121 {
 122     BOOL ret = FALSE;
 123     ULONG_PTR handle = (ULONG_PTR)hinternet;
 124     struct object_header *hdr = NULL;
 125
 126     EnterCriticalSection( &handle_cs );
 127
 128     if ((handle > 0) && (handle <= max_handles))
 129     {
 130         handle--;
 131         if (handles[handle])
 132         {
 133             hdr = handles[handle];
 134             TRACE("destroying handle 0x%lx for object %p\n", handle + 1, hdr);
 135             handles[handle] = NULL;
 136             ret = TRUE;
 137         }
 138     }
 139
 140     LeaveCriticalSection( &handle_cs );
 141
 142     if (hdr) release_object( hdr );
 143
 144     EnterCriticalSection( &handle_cs );
 145     if (next_handle > handle && !handles[handle]) next_handle = handle;
 146     LeaveCriticalSection( &handle_cs );
 147
 148     return ret;
 149 }