reactos/dll/win32/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 "winhttp_private.h"
  22
  23 #define HANDLE_CHUNK_SIZE 0x10
  24
  25 static CRITICAL_SECTION handle_cs;
  26 static CRITICAL_SECTION_DEBUG handle_cs_debug =
  27 {
  28     0, 0, &handle_cs,
  29     { &handle_cs_debug.ProcessLocksList, &handle_cs_debug.ProcessLocksList },
  30       0, 0, { (ULONG_PTR)(__FILE__ ": handle_cs") }
  31 };
  32 static CRITICAL_SECTION handle_cs = { &handle_cs_debug, -1, 0, 0, 0, 0 };
  33
  34 static object_header_t **handles;
  35 static ULONG_PTR next_handle;
  36 static ULONG_PTR max_handles;
  37
  38 object_header_t *addref_object( object_header_t *hdr )
  39 {
  40     ULONG refs = InterlockedIncrement( &hdr->refs );
  41     TRACE("%p -> refcount = %d\n", hdr, refs);
  42     return hdr;
  43 }
  44
  45 object_header_t *grab_object( HINTERNET hinternet )
  46 {
  47     object_header_t *hdr = NULL;
  48     ULONG_PTR handle = (ULONG_PTR)hinternet;
  49
  50     EnterCriticalSection( &handle_cs );
  51
  52     if ((handle > 0) && (handle <= max_handles) && handles[handle - 1])
  53         hdr = addref_object( handles[handle - 1] );
  54
  55     LeaveCriticalSection( &handle_cs );
  56
  57     TRACE("handle 0x%lx -> %p\n", handle, hdr);
  58     return hdr;
  59 }
  60
  61 void release_object( object_header_t *hdr )
  62 {
  63     ULONG refs = InterlockedDecrement( &hdr->refs );
  64     TRACE("object %p refcount = %d\n", hdr, refs);
  65     if (!refs)
  66     {
  67         if (hdr->type == WINHTTP_HANDLE_TYPE_REQUEST) close_connection( (request_t *)hdr );
  68
  69         send_callback( hdr, WINHTTP_CALLBACK_STATUS_HANDLE_CLOSING, &hdr->handle, sizeof(HINTERNET) );
  70
  71         TRACE("destroying object %p\n", hdr);
  72         if (hdr->type != WINHTTP_HANDLE_TYPE_SESSION) list_remove( &hdr->entry );
  73         hdr->vtbl->destroy( hdr );
  74     }
  75 }
  76
  77 HINTERNET alloc_handle( object_header_t *hdr )
  78 {
  79     object_header_t **p;
  80     ULONG_PTR handle, num;
  81
  82     list_init( &hdr->children );
  83     hdr->handle = NULL;
  84
  85     EnterCriticalSection( &handle_cs );
  86     if (!max_handles)
  87     {
  88         num = HANDLE_CHUNK_SIZE;
  89         if (!(p = heap_alloc_zero( sizeof(ULONG_PTR) * num ))) goto end;
  90         handles = p;
  91         max_handles = num;
  92     }
  93     if (max_handles == next_handle)
  94     {
  95         num = max_handles * 2;
  96         if (!(p = heap_realloc_zero( handles, sizeof(ULONG_PTR) * num ))) goto end;
  97         handles = p;
  98         max_handles = num;
  99     }
 100     handle = next_handle;
 101     if (handles[handle]) ERR("handle isn't free but should be\n");
 102
 103     handles[handle] = addref_object( hdr );
 104     hdr->handle = (HINTERNET)(handle + 1);
 105     while ((next_handle < max_handles) && handles[next_handle]) next_handle++;
 106
 107 end:
 108     LeaveCriticalSection( &handle_cs );
 109     return hdr->handle;
 110 }
 111
 112 BOOL free_handle( HINTERNET hinternet )
 113 {
 114     BOOL ret = FALSE;
 115     ULONG_PTR handle = (ULONG_PTR)hinternet;
 116     object_header_t *hdr = NULL, *child, *next;
 117
 118     EnterCriticalSection( &handle_cs );
 119
 120     if ((handle > 0) && (handle <= max_handles))
 121     {
 122         handle--;
 123         if (handles[handle])
 124         {
 125             hdr = handles[handle];
 126             TRACE("destroying handle 0x%lx for object %p\n", handle + 1, hdr);
 127             handles[handle] = NULL;
 128             ret = TRUE;
 129         }
 130     }
 131
 132     LeaveCriticalSection( &handle_cs );
 133
 134     if (hdr)
 135     {
 136         LIST_FOR_EACH_ENTRY_SAFE( child, next, &hdr->children, object_header_t, entry )
 137         {
 138             TRACE("freeing child handle %p for parent handle 0x%lx\n", child->handle, handle + 1);
 139             free_handle( child->handle );
 140         }
 141         release_object( hdr );
 142     }
 143
 144     EnterCriticalSection( &handle_cs );
 145     if (next_handle > handle && !handles[handle]) next_handle = handle;
 146     LeaveCriticalSection( &handle_cs );
 147
 148     return ret;
 149 }