On Fri, 15 Apr 2022, Nil Admirari wrote:
--- compat/w32dlfcn.h | 78 ++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 64 insertions(+), 14 deletions(-)diff --git a/compat/w32dlfcn.h b/compat/w32dlfcn.h index 52a94efa..0f41f50b 100644 --- a/compat/w32dlfcn.h +++ b/compat/w32dlfcn.h @@ -25,6 +25,30 @@ #if (_WIN32_WINNT < 0x0602) || HAVE_WINRT #include "libavutil/wchar_filename.h" #endif + +static inline wchar_t *get_module_filename(const HMODULE module) +{ + wchar_t *path = NULL, *new_path = NULL; + DWORD path_size = 0, path_len = 0; + + do { + path_size = path_size ? 2 * path_size : MAX_PATH; + new_path = av_realloc_array(path, path_size, sizeof *path); + if (!new_path) { + av_free(path); + return NULL; + } + path = new_path; + path_len = GetModuleFileNameW(module, path, path_size); + } while (path_len && path_size <= 32768 && path_size <= path_len); + + if (!path_len) { + av_free(path); + return NULL; + } + return path; +} + /** * Safe function used to open dynamic libs. This attempts to improve program security * by removing the current directory from the dll search path. Only dll's found in the @@ -34,29 +58,53 @@ */ static inline HMODULE win32_dlopen(const char *name) { + wchar_t *name_w = NULL; + if (utf8towchar(name, &name_w)) + name_w = NULL; #if _WIN32_WINNT < 0x0602 // Need to check if KB2533623 is available if (!GetProcAddress(GetModuleHandleW(L"kernel32.dll"), "SetDefaultDllDirectories")) { HMODULE module = NULL; - wchar_t *path = NULL, *name_w = NULL; - DWORD pathlen; - if (utf8towchar(name, &name_w)) + wchar_t *path = NULL, *new_path = NULL; + DWORD pathlen, pathsize, namelen; + if (!name_w) goto exit; - path = (wchar_t *)av_calloc(MAX_PATH, sizeof(wchar_t)); + namelen = wcslen(name_w); // Try local directory first - pathlen = GetModuleFileNameW(NULL, path, MAX_PATH); - pathlen = wcsrchr(path, '\\') - path; - if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH) + path = get_module_filename(NULL); + if (!path) goto exit; - path[pathlen] = '\\'; + new_path = wcsrchr(path, '\\'); + if (!new_path) + goto exit; + pathlen = new_path - path; + pathsize = pathlen + namelen + 2; + new_path = av_realloc_array(path, pathsize, sizeof *path); + if (!new_path) + goto exit; + path = new_path; wcscpy(path + pathlen + 1, name_w); module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH); if (module == NULL) { // Next try System32 directory - pathlen = GetSystemDirectoryW(path, MAX_PATH); - if (pathlen == 0 || pathlen + wcslen(name_w) + 2 > MAX_PATH) + pathlen = GetSystemDirectoryW(path, pathsize); + if (!pathlen) goto exit; - path[pathlen] = '\\'; + // Buffer is not enough in two cases: + // 1. system directory + \ + module name + // 2. system directory even without module name. + if (pathlen + namelen + 2 > pathsize) { + pathsize = pathlen + namelen + 2; + new_path = av_realloc_array(path, pathsize, sizeof *path); + if (!new_path) + goto exit; + path = new_path; + // Query again to handle case #2. + pathlen = GetSystemDirectoryW(path, pathsize); + if (!pathlen) + goto exit; + } + path[pathlen] = L'\\'; wcscpy(path + pathlen + 1, name_w); module = LoadLibraryExW(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH); } @@ -73,15 +121,17 @@ exit: # define LOAD_LIBRARY_SEARCH_SYSTEM32 0x00000800 #endif #if HAVE_WINRT - wchar_t *name_w = NULL; int ret; - if (utf8towchar(name, &name_w)) + if (!name_w) return NULL; ret = LoadPackagedLibrary(name_w, 0); av_free(name_w); return ret; #else - return LoadLibraryExA(name, NULL, LOAD_LIBRARY_SEARCH_APPLICATION_DIR | LOAD_LIBRARY_SEARCH_SYSTEM32); + /* filename may be be in CP_ACP */ + if (!name_w) + return LoadLibraryExA(name, NULL, LOAD_LIBRARY_SEARCH_APPLICATION_DIR | LOAD_LIBRARY_SEARCH_SYSTEM32); + return LoadLibraryExW(name_w, NULL, LOAD_LIBRARY_SEARCH_APPLICATION_DIR | LOAD_LIBRARY_SEARCH_SYSTEM32); #endif } #define dlopen(name, flags) win32_dlopen(name) -- 2.32.0
This looks ok to me. // Martin _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
