Function GetOpenFds

module/src/main/cpp/external/fdutils/fd_utils.cpp:300–323

static int ParseFd(dirent* dir_entry, int dir_fd);

std::unique_ptr<std::set<int>> GetOpenFds(fail_fn_t fail_fn) {
	DIR* proc_fd_dir = opendir(kFdPath);
	if (proc_fd_dir == nullptr) {
		fail_fn(android::base::StringPrintf("Unable to open directory %s: %s",
											kFdPath,
											strerror(errno)));
        return nullptr; // Return nullptr on error
	}
	auto result = std::make_unique<std::set<int>>();
	int dir_fd = dirfd(proc_fd_dir);
	dirent* dir_entry;
	while ((dir_entry = readdir(proc_fd_dir)) != nullptr) {
		const int fd = ParseFd(dir_entry, dir_fd);
		if (fd == -1) {
			continue;
		}

		result->insert(fd);
	}
	if (closedir(proc_fd_dir) == -1) {
		fail_fn(android::base::StringPrintf("Unable to close directory: %s", strerror(errno)));
        	}
	return result;
}

static int ParseFd(dirent* dir_entry, int dir_fd) {
	char* end;