WinINet APIを使用してHTTPSプロトコルのコンテンツ（https://～）を取得するコードです。
#include <string> #include <span> #include <optional> #include <vector> #define STRICT #define NOMINMAX #include <Windows.h> #pragma comment(lib, "wininet.lib") #include <wininet.h> #include "wil/resource.h" // wil::unique_hinternet // URL_COMPONENTSWを簡単に扱うためのクラス。 template <DWORD BUFFER_SIZE = 256> class URLComponentsW { public: URLComponentsW(std::wstring_view url, DWORD flags = 0) { URL_COMPONENTSW urlComps{ sizeof(URL_COMPONENTSW) }; m_scheme.resize(BUFFER_SIZE); m_hostname.resize(BUFFER_SIZE); m_username.resize(BUFFER_SIZE); m_password.resize(BUFFER_SIZE); m_path.resize(BUFFER_SIZE); m_extrainfo.resize(BUFFER_SIZE); urlComps.lpszScheme = m_scheme.data(); urlComps.dwSchemeLength = BUFFER_SIZE; urlComps.lpszHostName = m_hostname.data(); urlComps.dwHostNameLength = BUFFER_SIZE; urlComps.lpszUserName = m_username.data(); urlComps.dwUserNameLength = BUFFER_SIZE; urlComps.lpszPassword = m_password.data(); urlComps.dwPasswordLength = BUFFER_SIZE; urlComps.lpszUrlPath = m_path.data(); urlComps.dwUrlPathLength = BUFFER_SIZE; urlComps.lpszExtraInfo = m_extrainfo.data(); urlComps.dwExtraInfoLength = BUFFER_SIZE; if (!::InternetCrackUrlW(url.data(), 0, flags, &urlComps)) { m_nscheme = INTERNET_SCHEME_UNKNOWN; m_nport = 0; m_scheme.clear(); m_hostname.clear(); m_username.clear(); m_password.clear(); m_path.clear(); m_extrainfo.clear(); return; } m_nscheme = urlComps.nScheme; m_nport = urlComps.nPort; m_scheme.resize(urlComps.dwSchemeLength); m_hostname.resize(urlComps.dwHostNameLength); m_username.resize(urlComps.dwUserNameLength); m_password.resize(urlComps.dwPasswordLength); m_path.resize(urlComps.dwUrlPathLength); m_extrainfo.resize(urlComps.dwExtraInfoLength); m_scheme.shrink_to_fit(); m_hostname.shrink_to_fit(); m_username.shrink_to_fit(); m_password.shrink_to_fit(); m_path.shrink_to_fit(); m_extrainfo.shrink_to_fit(); } constexpr INTERNET_SCHEME nscheme() const noexcept { return m_nscheme; } constexpr INTERNET_PORT nport() const noexcept { return m_nport; } constexpr const std::wstring& scheme() const noexcept { return m_scheme; } constexpr const std::wstring& hostname() const noexcept { return m_hostname; } constexpr const std::wstring& username() const noexcept { return m_username; } constexpr const std::wstring& password() const noexcept { return m_password; } constexpr const std::wstring& path() const noexcept { return m_path; } constexpr const std::wstring& extrainfo() const noexcept { return m_extrainfo; } constexpr bool empty() const noexcept { return m_nscheme == INTERNET_SCHEME_UNKNOWN && m_nport == 0 && m_scheme.empty() && m_hostname.empty() && m_username.empty() && m_password.empty() && m_path.empty() && m_extrainfo.empty(); } private: INTERNET_SCHEME m_nscheme; INTERNET_PORT m_nport; std::wstring m_scheme; std::wstring m_hostname; std::wstring m_username; std::wstring m_password; std::wstring m_path; std::wstring m_extrainfo; }; template <DWORD BUFFER_LEN = 1024> std::wstring HttpQueryInfoW(HINTERNET hinternet, DWORD infoLevel) { std::wstring data; DWORD index = 0; std::wstring buffer(BUFFER_LEN, 0); for (;;) { DWORD bufferLen = BUFFER_LEN; auto f = ::HttpQueryInfoW(hinternet, infoLevel, buffer.data(), &bufferLen, &index); if (f) buffer.resize(bufferLen); else if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) return {}; data.append(buffer); if (f) break; } return data; } std::optional<DWORD> HttpQueryInfoAsNumber(HINTERNET hinternet, DWORD infoLevel, LPDWORD index = nullptr) { DWORD dw; DWORD bufferLen = sizeof(DWORD); if (!::HttpQueryInfoW(hinternet, infoLevel | HTTP_QUERY_FLAG_NUMBER, &dw, &bufferLen, index)) return {}; return dw; } template <DWORD BUFFER_SIZE = 1024> std::vector<BYTE> InternetReadAllFile(HINTERNET hfile) { std::vector<BYTE> data; for (;;) { std::vector<BYTE> buffer(BUFFER_SIZE, 0); DWORD bytesRead = 0; if (!InternetReadFile(hfile, buffer.data(), BUFFER_SIZE, &bytesRead)) return {}; if (bytesRead == 0) break; data.insert(data.cend(), buffer.cbegin(), buffer.cend()); } data.shrink_to_fit(); return data; } bool FetchHttpsResponseHeaderAndContent( HINTERNET hinternet, std::wstring_view url, std::wstring& responseHeader, std::vector<BYTE>& content) { responseHeader.clear(); content.clear(); // URLの分解 URLComponentsW urlComp(url); if (urlComp.empty() || urlComp.nscheme() != INTERNET_SCHEME_HTTPS) return false; // 接続の確立 wil::unique_hinternet hconnect; hconnect.reset(::InternetConnectW(hinternet, urlComp.hostname().data(), INTERNET_DEFAULT_HTTPS_PORT, urlComp.username().data(), urlComp.password().data(), INTERNET_SERVICE_HTTP, INTERNET_FLAG_RELOAD // キャッシュの無視 | INTERNET_FLAG_NO_AUTO_REDIRECT, // リダイレクトの無効化 0)); if (!hconnect) return {}; // リクエストの作成 wil::unique_hinternet hrequest; hrequest.reset(::HttpOpenRequestW(hconnect.get(), L"GET", (urlComp.path() + urlComp.extrainfo()).data(), nullptr, nullptr, nullptr, INTERNET_FLAG_SECURE, 0)); if (!hrequest) return {}; // リクエストの送信 if (!::HttpSendRequestW(hrequest.get(), nullptr, 0, nullptr, 0)) return false; // ステータスコードの確認 auto statusCode = HttpQueryInfoAsNumber(hrequest.get(), HTTP_QUERY_STATUS_CODE); if (statusCode != HTTP_STATUS_OK) return false; responseHeader = HttpQueryInfoW(hrequest.get(), HTTP_QUERY_RAW_HEADERS_CRLF); content = InternetReadAllFile(hrequest.get()); return true; } std::optional<std::wstring> ConvUTF8ToUTF16(std::span<BYTE> buffer) { if (buffer.size() > INT_MAX) return {}; auto len = ::MultiByteToWideChar(CP_UTF8, 0, std::bit_cast<LPCCH>(buffer.data()), buffer.size(), nullptr, 0); if (len == 0 && ::GetLastError() != 0) return {}; std::wstring s(len, L'\0'); if (!::MultiByteToWideChar(CP_UTF8, 0, std::bit_cast<LPCCH>(buffer.data()), buffer.size(), s.data(), len)) return {}; return s; } int main() { // 適当なHTTPSプロトコルのURLを指定します。 const auto url = L<"https://～">; // Windows Internet APIの初期化 wil::unique_hinternet hinternet; hinternet.reset(::InternetOpenW(nullptr, INTERNET_OPEN_TYPE_PRECONFIG, nullptr, nullptr, 0)); if (!hinternet) return -1; std::wstring responseHeader; std::vector<BYTE> content; if (!FetchHttpsResponseHeaderAndContent(hinternet.get(), url, responseHeader, content)) return - 1; // UTF-8エンコーディングと決め打ちして変換 auto html = ConvUTF8ToUTF16(content); return 0; }
