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Diffstat (limited to 'Utilities/cmexpat/lib/loadlibrary.c')
| -rw-r--r-- | Utilities/cmexpat/lib/loadlibrary.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/Utilities/cmexpat/lib/loadlibrary.c b/Utilities/cmexpat/lib/loadlibrary.c new file mode 100644 index 0000000..ffce868 --- /dev/null +++ b/Utilities/cmexpat/lib/loadlibrary.c @@ -0,0 +1,141 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 2016 - 2017, Steve Holme, <steve_holme@hotmail.com>. + * + * All rights reserved. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF + * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF + * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH + * THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the name of a copyright holder shall + * not be used in advertising or otherwise to promote the sale, use or other + * dealings in this Software without prior written authorization of the + * copyright holder. + * + ***************************************************************************/ + +#if defined(_WIN32) + +#include <windows.h> +#include <tchar.h> + + +HMODULE _Expat_LoadLibrary(LPCTSTR filename); + + +#if !defined(LOAD_WITH_ALTERED_SEARCH_PATH) +#define LOAD_WITH_ALTERED_SEARCH_PATH 0x00000008 +#endif + +#if !defined(LOAD_LIBRARY_SEARCH_SYSTEM32) +#define LOAD_LIBRARY_SEARCH_SYSTEM32 0x00000800 +#endif + +/* We use our own typedef here since some headers might lack these */ +typedef HMODULE (APIENTRY *LOADLIBRARYEX_FN)(LPCTSTR, HANDLE, DWORD); + +/* See function definitions in winbase.h */ +#ifdef UNICODE +# ifdef _WIN32_WCE +# define LOADLIBARYEX L"LoadLibraryExW" +# else +# define LOADLIBARYEX "LoadLibraryExW" +# endif +#else +# define LOADLIBARYEX "LoadLibraryExA" +#endif + + +/* + * _Expat_LoadLibrary() + * + * This is used to dynamically load DLLs using the most secure method available + * for the version of Windows that we are running on. + * + * Parameters: + * + * filename [in] - The filename or full path of the DLL to load. If only the + * filename is passed then the DLL will be loaded from the + * Windows system directory. + * + * Returns the handle of the module on success; otherwise NULL. + */ +HMODULE _Expat_LoadLibrary(LPCTSTR filename) +{ + HMODULE hModule = NULL; + LOADLIBRARYEX_FN pLoadLibraryEx = NULL; + + /* Get a handle to kernel32 so we can access it's functions at runtime */ + HMODULE hKernel32 = GetModuleHandle(TEXT("kernel32")); + if(!hKernel32) + return NULL; + + /* Attempt to find LoadLibraryEx() which is only available on Windows 2000 + and above */ + pLoadLibraryEx = (LOADLIBRARYEX_FN) GetProcAddress(hKernel32, LOADLIBARYEX); + + /* Detect if there's already a path in the filename and load the library if + there is. Note: Both back slashes and forward slashes have been supported + since the earlier days of DOS at an API level although they are not + supported by command prompt */ + if(_tcspbrk(filename, TEXT("\\/"))) { + /** !checksrc! disable BANNEDFUNC 1 **/ + hModule = pLoadLibraryEx ? + pLoadLibraryEx(filename, NULL, LOAD_WITH_ALTERED_SEARCH_PATH) : + LoadLibrary(filename); + } + /* Detect if KB2533623 is installed, as LOAD_LIBARY_SEARCH_SYSTEM32 is only + supported on Windows Vista, Windows Server 2008, Windows 7 and Windows + Server 2008 R2 with this patch or natively on Windows 8 and above */ + else if(pLoadLibraryEx && GetProcAddress(hKernel32, "AddDllDirectory")) { + /* Load the DLL from the Windows system directory */ + hModule = pLoadLibraryEx(filename, NULL, LOAD_LIBRARY_SEARCH_SYSTEM32); + } + else { + /* Attempt to get the Windows system path */ + UINT systemdirlen = GetSystemDirectory(NULL, 0); + if(systemdirlen) { + /* Allocate space for the full DLL path (Room for the null terminator + is included in systemdirlen) */ + size_t filenamelen = _tcslen(filename); + TCHAR *path = malloc(sizeof(TCHAR) * (systemdirlen + 1 + filenamelen)); + if(path && GetSystemDirectory(path, systemdirlen)) { + /* Calculate the full DLL path */ + _tcscpy(path + _tcslen(path), TEXT("\\")); + _tcscpy(path + _tcslen(path), filename); + + /* Load the DLL from the Windows system directory */ + /** !checksrc! disable BANNEDFUNC 1 **/ + hModule = pLoadLibraryEx ? + pLoadLibraryEx(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH) : + LoadLibrary(path); + + } + free(path); + } + } + + return hModule; +} + +#else /* defined(_WIN32) */ + +/* ISO C requires a translation unit to contain at least one declaration + [-Wempty-translation-unit] */ +typedef int _TRANSLATION_UNIT_LOAD_LIBRARY_C_NOT_EMTPY; + +#endif /* defined(_WIN32) */ |