diff options
Diffstat (limited to 'src/c-ares/ares_library_init.c')
-rw-r--r-- | src/c-ares/ares_library_init.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/src/c-ares/ares_library_init.c b/src/c-ares/ares_library_init.c new file mode 100644 index 000000000..c885a16c8 --- /dev/null +++ b/src/c-ares/ares_library_init.c @@ -0,0 +1,167 @@ + +/* Copyright 1998 by the Massachusetts Institute of Technology. + * Copyright (C) 2004-2009 by Daniel Stenberg + * + * Permission to use, copy, modify, and distribute this + * software and its documentation for any purpose and without + * fee is hereby granted, provided that the above copyright + * notice appear in all copies and that both that copyright + * notice and this permission notice appear in supporting + * documentation, and that the name of M.I.T. not be used in + * advertising or publicity pertaining to distribution of the + * software without specific, written prior permission. + * M.I.T. makes no representations about the suitability of + * this software for any purpose. It is provided "as is" + * without express or implied warranty. + */ + +#include "ares_setup.h" + +#include "ares.h" +#include "ares_library_init.h" +#include "ares_private.h" + +/* library-private global and unique instance vars */ + +#ifdef USE_WINSOCK +fpGetNetworkParams_t ares_fpGetNetworkParams = ZERO_NULL; +fpSystemFunction036_t ares_fpSystemFunction036 = ZERO_NULL; +fpGetAdaptersAddresses_t ares_fpGetAdaptersAddresses = ZERO_NULL; +#endif + +/* library-private global vars with source visibility restricted to this file */ + +static unsigned int ares_initialized; +static int ares_init_flags; + +/* library-private global vars with visibility across the whole library */ +void *(*ares_malloc)(size_t size) = malloc; +void *(*ares_realloc)(void *ptr, size_t size) = realloc; +void (*ares_free)(void *ptr) = free; + +#ifdef USE_WINSOCK +static HMODULE hnd_iphlpapi; +static HMODULE hnd_advapi32; +#endif + + +static int ares_win32_init(void) +{ +#ifdef USE_WINSOCK + + hnd_iphlpapi = 0; + hnd_iphlpapi = LoadLibraryW(L"iphlpapi.dll"); + if (!hnd_iphlpapi) + return ARES_ELOADIPHLPAPI; + + ares_fpGetNetworkParams = (fpGetNetworkParams_t) + GetProcAddress(hnd_iphlpapi, "GetNetworkParams"); + if (!ares_fpGetNetworkParams) + { + FreeLibrary(hnd_iphlpapi); + return ARES_EADDRGETNETWORKPARAMS; + } + + ares_fpGetAdaptersAddresses = (fpGetAdaptersAddresses_t) + GetProcAddress(hnd_iphlpapi, "GetAdaptersAddresses"); + if (!ares_fpGetAdaptersAddresses) + { + /* This can happen on clients before WinXP, I don't + think it should be an error, unless we don't want to + support Windows 2000 anymore */ + } + + /* + * When advapi32.dll is unavailable or advapi32.dll has no SystemFunction036, + * also known as RtlGenRandom, which is the case for Windows versions prior + * to WinXP then c-ares uses portable rand() function. Then don't error here. + */ + + hnd_advapi32 = 0; + hnd_advapi32 = LoadLibraryW(L"advapi32.dll"); + if (hnd_advapi32) + { + ares_fpSystemFunction036 = (fpSystemFunction036_t) + GetProcAddress(hnd_advapi32, "SystemFunction036"); + } + +#endif + return ARES_SUCCESS; +} + + +static void ares_win32_cleanup(void) +{ +#ifdef USE_WINSOCK + if (hnd_advapi32) + FreeLibrary(hnd_advapi32); + if (hnd_iphlpapi) + FreeLibrary(hnd_iphlpapi); +#endif +} + + +int ares_library_init(int flags) +{ + int res; + + if (ares_initialized) + { + ares_initialized++; + return ARES_SUCCESS; + } + ares_initialized++; + + if (flags & ARES_LIB_INIT_WIN32) + { + res = ares_win32_init(); + if (res != ARES_SUCCESS) + return res; /* LCOV_EXCL_LINE: can't test Win32 init failure */ + } + + ares_init_flags = flags; + + return ARES_SUCCESS; +} + +int ares_library_init_mem(int flags, + void *(*amalloc)(size_t size), + void (*afree)(void *ptr), + void *(*arealloc)(void *ptr, size_t size)) +{ + if (amalloc) + ares_malloc = amalloc; + if (arealloc) + ares_realloc = arealloc; + if (afree) + ares_free = afree; + return ares_library_init(flags); +} + + +void ares_library_cleanup(void) +{ + if (!ares_initialized) + return; + ares_initialized--; + if (ares_initialized) + return; + + if (ares_init_flags & ARES_LIB_INIT_WIN32) + ares_win32_cleanup(); + + ares_init_flags = ARES_LIB_INIT_NONE; + ares_malloc = malloc; + ares_realloc = realloc; + ares_free = free; +} + + +int ares_library_initialized(void) +{ +#ifdef USE_WINSOCK + if (!ares_initialized) + return ARES_ENOTINITIALIZED; +#endif + return ARES_SUCCESS; +} |