2 /* Copyright 1998 by the Massachusetts Institute of Technology.
3 * Copyright (C) 2004-2009 by Daniel Stenberg
5 * Permission to use, copy, modify, and distribute this
6 * software and its documentation for any purpose and without
7 * fee is hereby granted, provided that the above copyright
8 * notice appear in all copies and that both that copyright
9 * notice and this permission notice appear in supporting
10 * documentation, and that the name of M.I.T. not be used in
11 * advertising or publicity pertaining to distribution of the
12 * software without specific, written prior permission.
13 * M.I.T. makes no representations about the suitability of
14 * this software for any purpose. It is provided "as is"
15 * without express or implied warranty.
18 #include "ares_setup.h"
21 #include "ares_library_init.h"
22 #include "ares_private.h"
24 /* library-private global and unique instance vars */
27 fpGetNetworkParams_t ares_fpGetNetworkParams = ZERO_NULL;
28 fpSystemFunction036_t ares_fpSystemFunction036 = ZERO_NULL;
31 /* library-private global vars with source visibility restricted to this file */
33 static unsigned int ares_initialized;
34 static int ares_init_flags;
37 static HMODULE hnd_iphlpapi;
38 static HMODULE hnd_advapi32;
42 static int ares_win32_init(void)
47 hnd_iphlpapi = LoadLibrary("iphlpapi.dll");
49 return ARES_ELOADIPHLPAPI;
51 ares_fpGetNetworkParams = (fpGetNetworkParams_t)
52 GetProcAddress(hnd_iphlpapi, "GetNetworkParams");
53 if (!ares_fpGetNetworkParams)
55 FreeLibrary(hnd_iphlpapi);
56 return ARES_EADDRGETNETWORKPARAMS;
60 * When advapi32.dll is unavailable or advapi32.dll has no SystemFunction036,
61 * also known as RtlGenRandom, which is the case for Windows versions prior
62 * to WinXP then c-ares uses portable rand() function. Then don't error here.
66 hnd_advapi32 = LoadLibrary("advapi32.dll");
69 ares_fpSystemFunction036 = (fpSystemFunction036_t)
70 GetProcAddress(hnd_advapi32, "SystemFunction036");
78 static void ares_win32_cleanup(void)
82 FreeLibrary(hnd_advapi32);
84 FreeLibrary(hnd_iphlpapi);
89 int ares_library_init(int flags)
97 if (flags & ARES_LIB_INIT_WIN32)
99 res = ares_win32_init();
100 if (res != ARES_SUCCESS)
104 ares_init_flags = flags;
110 void ares_library_cleanup(void)
112 if (!ares_initialized)
116 if (ares_init_flags & ARES_LIB_INIT_WIN32)
117 ares_win32_cleanup();
119 ares_init_flags = ARES_LIB_INIT_NONE;
123 int ares_library_initialized(void)
126 if (!ares_initialized)
127 return ARES_ENOTINITIALIZED;