blob: bc9bb8c9f51e8a78627bbeabe61348cb42999729
| 1 | /* |
| 2 | * This file is part of FFmpeg. |
| 3 | * |
| 4 | * FFmpeg is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * FFmpeg is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with FFmpeg; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | #ifndef COMPAT_W32DLFCN_H |
| 20 | #define COMPAT_W32DLFCN_H |
| 21 | |
| 22 | #ifdef _WIN32 |
| 23 | #include <windows.h> |
| 24 | #if _WIN32_WINNT < 0x0602 |
| 25 | #include "libavutil/wchar_filename.h" |
| 26 | #endif |
| 27 | /** |
| 28 | * Safe function used to open dynamic libs. This attempts to improve program security |
| 29 | * by removing the current directory from the dll search path. Only dll's found in the |
| 30 | * executable or system directory are allowed to be loaded. |
| 31 | * @param name The dynamic lib name. |
| 32 | * @return A handle to the opened lib. |
| 33 | */ |
| 34 | static inline HMODULE win32_dlopen(const char *name) |
| 35 | { |
| 36 | #if _WIN32_WINNT < 0x0602 |
| 37 | // Need to check if KB2533623 is available |
| 38 | if (!GetProcAddress(GetModuleHandleW(L"kernel32.dll"), "SetDefaultDllDirectories")) { |
| 39 | HMODULE module = NULL; |
| 40 | wchar_t *path = NULL, *name_w = NULL; |
| 41 | DWORD pathlen; |
| 42 | if (utf8towchar(name, &name_w)) |
| 43 | goto exit; |
| 44 | path = (wchar_t *)av_mallocz_array(MAX_PATH, sizeof(wchar_t)); |
| 45 | // Try local directory first |
| 46 | pathlen = GetModuleFileNameW(NULL, path, MAX_PATH); |
| 47 | pathlen = wcsrchr(path, '\\') - path; |
| 48 | if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH) |
| 49 | goto exit; |
| 50 | path[pathlen] = '\\'; |
| 51 | wcscpy(path + pathlen + 1, name_w); |
| 52 | module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH); |
| 53 | if (module == NULL) { |
| 54 | // Next try System32 directory |
| 55 | pathlen = GetSystemDirectoryW(path, MAX_PATH); |
| 56 | if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH) |
| 57 | goto exit; |
| 58 | path[pathlen] = '\\'; |
| 59 | wcscpy(path + pathlen + 1, name_w); |
| 60 | module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH); |
| 61 | } |
| 62 | exit: |
| 63 | av_free(path); |
| 64 | av_free(name_w); |
| 65 | return module; |
| 66 | } |
| 67 | #endif |
| 68 | #ifndef LOAD_LIBRARY_SEARCH_APPLICATION_DIR |
| 69 | # define LOAD_LIBRARY_SEARCH_APPLICATION_DIR 0x00000200 |
| 70 | #endif |
| 71 | #ifndef LOAD_LIBRARY_SEARCH_SYSTEM32 |
| 72 | # define LOAD_LIBRARY_SEARCH_SYSTEM32 0x00000800 |
| 73 | #endif |
| 74 | return LoadLibraryExA(name, NULL, LOAD_LIBRARY_SEARCH_APPLICATION_DIR | LOAD_LIBRARY_SEARCH_SYSTEM32); |
| 75 | } |
| 76 | #define dlopen(name, flags) win32_dlopen(name) |
| 77 | #define dlclose FreeLibrary |
| 78 | #define dlsym GetProcAddress |
| 79 | #else |
| 80 | #include <dlfcn.h> |
| 81 | #endif |
| 82 | |
| 83 | #endif /* COMPAT_W32DLFCN_H */ |
| 84 |