qswiki/gateway/httplib.h

//
//  httplib.h
//  Copyright (c) 2018 Albert S. All rights reserved. 
//  Copyright (c) 2017 Yuji Hirose. All rights reserved.
//  MIT License
//

#ifndef _CPPHTTPLIB_HTTPLIB_H_
#define _CPPHTTPLIB_HTTPLIB_H_

#ifdef _WIN32
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#endif
#ifndef _CRT_NONSTDC_NO_DEPRECATE
#define _CRT_NONSTDC_NO_DEPRECATE
#endif

#if defined(_MSC_VER) && _MSC_VER < 1900
#define snprintf _snprintf_s
#endif

#ifndef S_ISREG
#define S_ISREG(m)  (((m)&S_IFREG)==S_IFREG)
#endif
#ifndef S_ISDIR
#define S_ISDIR(m)  (((m)&S_IFDIR)==S_IFDIR)
#endif

#include <io.h>
#include <winsock2.h>
#include <ws2tcpip.h>

#undef min
#undef max

#ifndef strcasecmp
#define strcasecmp _stricmp
#endif

typedef SOCKET socket_t;
#else
#include <pthread.h>
#include <unistd.h>
#include <netdb.h>
#include <cstring>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <signal.h>
#include <sys/socket.h>
#include <sys/select.h>

typedef int socket_t;
#define INVALID_SOCKET (-1)
#endif

#include <fstream>
#include <functional>
#include <map>
#include <memory>
#include <mutex>
#include <boost/regex.hpp>
#include <string>
#include <thread>
#include <sys/stat.h>
#include <fcntl.h>
#include <assert.h>

#ifdef CPPHTTPLIB_OPENSSL_SUPPORT
#include <openssl/ssl.h>
#endif

#ifdef CPPHTTPLIB_ZLIB_SUPPORT
#include <zlib.h>
#endif

/*
 * Configuration
 */
#define CPPHTTPLIB_KEEPALIVE_TIMEOUT_SECOND 5
#define CPPHTTPLIB_KEEPALIVE_TIMEOUT_USECOND 0

namespace httplib
{

namespace detail {

struct ci {
	bool operator() (const std::string & s1, const std::string & s2) const {
		return std::lexicographical_compare(
			s1.begin(), s1.end(),
			s2.begin(), s2.end(),
			[](char c1, char c2) {
				return ::tolower(c1) < ::tolower(c2);
			});
	}
};

} // namespace detail

enum class HttpVersion { v1_0 = 0, v1_1 };

typedef std::multimap<std::string, std::string, detail::ci>  Headers;

template<typename uint64_t, typename... Args>
std::pair<std::string, std::string> make_range_header(uint64_t value, Args... args);

typedef std::multimap<std::string, std::string>				Params;
typedef boost::smatch											Match;
typedef std::function<bool (uint64_t current, uint64_t total)> Progress;

struct MultipartFile {
	std::string filename;
	std::string content_type;
	size_t offset = 0;
	size_t length = 0;
};
typedef std::multimap<std::string, MultipartFile> MultipartFiles;

struct Request {
	std::string	version;
	std::string	method;
	std::string	target;
	std::string	path;
	Headers		headers;
	std::string	body;
	Params		 params;
	MultipartFiles files;
	Match		  matches;

	Progress	   progress;

	bool has_header(const char* key) const;
	std::string get_header_value(const char* key) const;
	void set_header(const char* key, const char* val);

	bool has_param(const char* key) const;
	std::string get_param_value(const char* key) const;

	bool has_file(const char* key) const;
	MultipartFile get_file_value(const char* key) const;
};

struct Response {
	std::string version;
	int		 status;
	Headers	 headers;
	std::string body;
	std::function<std::string (uint64_t offset)> streamcb;

	bool has_header(const char* key) const;
	std::string get_header_value(const char* key) const;
	void set_header(const char* key, const char* val);

	void set_redirect(const char* uri);
	void set_content(const char* s, size_t n, const char* content_type);
	void set_content(const std::string& s, const char* content_type);

	Response() : status(-1) {}
};

class Stream {
public:
	virtual ~Stream() {}
	virtual int read(char* ptr, size_t size) = 0;
	virtual int write(const char* ptr, size_t size1) = 0;
	virtual int write(const char* ptr) = 0;
	virtual std::string get_remote_addr() = 0;

	template <typename ...Args>
	void write_format(const char* fmt, const Args& ...args);
};

class SocketStream : public Stream {
public:
	SocketStream(socket_t sock);
	virtual ~SocketStream();

	virtual int read(char* ptr, size_t size);
	virtual int write(const char* ptr, size_t size);
	virtual int write(const char* ptr);
	virtual std::string get_remote_addr();

private:
	socket_t sock_;
};

class Server {
public:
	typedef std::function<void (const Request&, Response&)> Handler;
	typedef std::function<void (const Request&, const Response&)> Logger;

	Server();

	virtual ~Server();

	virtual bool is_valid() const;

	Server& Get(const char* pattern, Handler handler);
	Server& Post(const char* pattern, Handler handler);

	Server& Put(const char* pattern, Handler handler);
	Server& Delete(const char* pattern, Handler handler);
	Server& Options(const char* pattern, Handler handler);

	bool set_base_dir(const char* path);

	void set_error_handler(Handler handler);
	void set_logger(Logger logger);

	void set_keep_alive_max_count(size_t count);

	int bind_to_any_port(const char* host, int socket_flags = 0);
	bool listen_after_bind();

	bool listen(const char* host, int port, int socket_flags = 0);

	bool is_running() const;
	void stop();

protected:
	bool process_request(Stream& strm, bool last_connection, bool& connection_close);

	size_t keep_alive_max_count_;

private:
	typedef std::vector<std::pair<boost::regex, Handler>> Handlers;

	socket_t create_server_socket(const char* host, int port, int socket_flags) const;
	int bind_internal(const char* host, int port, int socket_flags);
	bool listen_internal();

	bool routing(Request& req, Response& res);
	bool handle_file_request(Request& req, Response& res);
	bool dispatch_request(Request& req, Response& res, Handlers& handlers);

	bool parse_request_line(const char* s, Request& req);
	void write_response(Stream& strm, bool last_connection, const Request& req, Response& res);

	virtual bool read_and_close_socket(socket_t sock);

	bool		is_running_;
	socket_t	svr_sock_;
	std::string base_dir_;
	Handlers	get_handlers_;
	Handlers	post_handlers_;
	Handlers	put_handlers_;
	Handlers	delete_handlers_;
	Handlers	options_handlers_;
	Handler	 error_handler_;
	Logger	  logger_;

	// TODO: Use thread pool...
	std::mutex  running_threads_mutex_;
	int		 running_threads_;
};

class Client {
public:
	Client(
		const char* host,
		int port = 80,
		time_t timeout_sec = 300);

	virtual ~Client();

	virtual bool is_valid() const;

	std::shared_ptr<Response> Get(const char* path, Progress progress = nullptr);
	std::shared_ptr<Response> Get(const char* path, const Headers& headers, Progress progress = nullptr);

	std::shared_ptr<Response> Head(const char* path);
	std::shared_ptr<Response> Head(const char* path, const Headers& headers);

	std::shared_ptr<Response> Post(const char* path, const std::string& body, const char* content_type);
	std::shared_ptr<Response> Post(const char* path, const Headers& headers, const std::string& body, const char* content_type);

	std::shared_ptr<Response> Post(const char* path, const Params& params);
	std::shared_ptr<Response> Post(const char* path, const Headers& headers, const Params& params);

	std::shared_ptr<Response> Put(const char* path, const std::string& body, const char* content_type);
	std::shared_ptr<Response> Put(const char* path, const Headers& headers, const std::string& body, const char* content_type);

	std::shared_ptr<Response> Delete(const char* path);
	std::shared_ptr<Response> Delete(const char* path, const Headers& headers);

	std::shared_ptr<Response> Options(const char* path);
	std::shared_ptr<Response> Options(const char* path, const Headers& headers);

	bool send(Request& req, Response& res);

protected:
	bool process_request(Stream& strm, Request& req, Response& res, bool& connection_close);

	const std::string host_;
	const int		 port_;
	time_t			timeout_sec_;
	const std::string host_and_port_;

private:
	socket_t create_client_socket() const;
	bool read_response_line(Stream& strm, Response& res);
	void write_request(Stream& strm, Request& req);

	virtual bool read_and_close_socket(socket_t sock, Request& req, Response& res);
};

#ifdef CPPHTTPLIB_OPENSSL_SUPPORT
class SSLSocketStream : public Stream {
public:
	SSLSocketStream(socket_t sock, SSL* ssl);
	virtual ~SSLSocketStream();

	virtual int read(char* ptr, size_t size);
	virtual int write(const char* ptr, size_t size);
	virtual int write(const char* ptr);
	virtual std::string get_remote_addr();

private:
	socket_t sock_;
	SSL* ssl_;
};

class SSLServer : public Server {
public:
	SSLServer(
		const char* cert_path, const char* private_key_path);

	virtual ~SSLServer();

	virtual bool is_valid() const;

private:
	virtual bool read_and_close_socket(socket_t sock);

	SSL_CTX* ctx_;
	std::mutex ctx_mutex_;
};

class SSLClient : public Client {
public:
	SSLClient(
		const char* host,
		int port = 80,
		time_t timeout_sec = 300);

	virtual ~SSLClient();

	virtual bool is_valid() const;

private:
	virtual bool read_and_close_socket(socket_t sock, Request& req, Response& res);

	SSL_CTX* ctx_;
	std::mutex ctx_mutex_;
};
#endif

/*
 * Implementation
 */
namespace detail {

template <class Fn>
void split(const char* b, const char* e, char d, Fn fn)
{
	int i = 0;
	int beg = 0;

	while (e ? (b + i != e) : (b[i] != '\0')) {
		if (b[i] == d) {
			fn(&b[beg], &b[i]);
			beg = i + 1;
		}
		i++;
	}

	if (i) {
		fn(&b[beg], &b[i]);
	}
}

// NOTE: until the read size reaches `fixed_buffer_size`, use `fixed_buffer`
// to store data. The call can set memory on stack for performance.
class stream_line_reader {
public:
	stream_line_reader(Stream& strm, char* fixed_buffer, size_t fixed_buffer_size)
		: strm_(strm)
		, fixed_buffer_(fixed_buffer)
		, fixed_buffer_size_(fixed_buffer_size) {
	}

	const char* ptr() const {
		if (glowable_buffer_.empty()) {
			return fixed_buffer_;
		} else {
			return glowable_buffer_.data();
		}
	}

	bool getline() {
		fixed_buffer_used_size_ = 0;
		glowable_buffer_.clear();

		for (size_t i = 0; ; i++) {
			char byte;
			auto n = strm_.read(&byte, 1);

			if (n < 0) {
				return false;
			} else if (n == 0) {
				if (i == 0) {
					return false;
				} else {
					break;
				}
			}

			append(byte);

			if (byte == '\n') {
				break;
			}
		}

		return true;
	}

private:
	void append(char c) {
		if (fixed_buffer_used_size_ < fixed_buffer_size_ - 1) {
			fixed_buffer_[fixed_buffer_used_size_++] = c;
			fixed_buffer_[fixed_buffer_used_size_] = '\0';
		} else {
			if (glowable_buffer_.empty()) {
				assert(fixed_buffer_[fixed_buffer_used_size_] == '\0');
				glowable_buffer_.assign(fixed_buffer_, fixed_buffer_used_size_);
			}
			glowable_buffer_ += c;
		}
	}

	Stream& strm_;
	char* fixed_buffer_;
	const size_t fixed_buffer_size_;
	size_t fixed_buffer_used_size_;
	std::string glowable_buffer_;
};

inline int close_socket(socket_t sock)
{
#ifdef _WIN32
	return closesocket(sock);
#else
	return close(sock);
#endif
}

inline int select_read(socket_t sock, time_t sec, time_t usec)
{
	fd_set fds;
	FD_ZERO(&fds);
	FD_SET(sock, &fds);

	timeval tv;
	tv.tv_sec = sec;
	tv.tv_usec = usec;

	return select(sock + 1, &fds, NULL, NULL, &tv);
}

inline bool wait_until_socket_is_ready(socket_t sock, time_t sec, time_t usec)
{
	fd_set fdsr;
	FD_ZERO(&fdsr);
	FD_SET(sock, &fdsr);

	auto fdsw = fdsr;
	auto fdse = fdsr;

	timeval tv;
	tv.tv_sec = sec;
	tv.tv_usec = usec;

	if (select(sock + 1, &fdsr, &fdsw, &fdse, &tv) < 0) {
		return false;
	} else if (FD_ISSET(sock, &fdsr) || FD_ISSET(sock, &fdsw)) {
		int error = 0;
		socklen_t len = sizeof(error);
		if (getsockopt(sock, SOL_SOCKET, SO_ERROR, (char*)&error, &len) < 0 || error) {
			return false;
		}
	} else {
		return false;
	}

	return true;
}

template <typename T>
inline bool read_and_close_socket(socket_t sock, size_t keep_alive_max_count, T callback)
{
	bool ret = false;

	if (keep_alive_max_count > 0) {
		auto count = keep_alive_max_count;
		while (count > 0 &&
			   detail::select_read(sock,
				   CPPHTTPLIB_KEEPALIVE_TIMEOUT_SECOND,
				   CPPHTTPLIB_KEEPALIVE_TIMEOUT_USECOND) > 0) {
			SocketStream strm(sock);
			auto last_connection = count == 1;
			auto connection_close = false;

			ret = callback(strm, last_connection, connection_close);
			if (!ret || connection_close) {
				break;
			}

			count--;
		}
	} else {
		SocketStream strm(sock);
		auto dummy_connection_close = false;
		ret = callback(strm, true, dummy_connection_close);
	}

	close_socket(sock);
	return ret;
}

inline int shutdown_socket(socket_t sock)
{
#ifdef _WIN32
	return shutdown(sock, SD_BOTH);
#else
	return shutdown(sock, SHUT_RDWR);
#endif
}

template <typename Fn>
socket_t create_socket(const char* host, int port, Fn fn, int socket_flags = 0)
{
#ifdef _WIN32
#define SO_SYNCHRONOUS_NONALERT 0x20
#define SO_OPENTYPE 0x7008

	int opt = SO_SYNCHRONOUS_NONALERT;
	setsockopt(INVALID_SOCKET, SOL_SOCKET, SO_OPENTYPE, (char*)&opt, sizeof(opt));
#endif

	// Get address info
	struct addrinfo hints;
	struct addrinfo *result;

	memset(&hints, 0, sizeof(struct addrinfo));
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_flags = socket_flags;
	hints.ai_protocol = 0;

	auto service = std::to_string(port);

	if (getaddrinfo(host, service.c_str(), &hints, &result)) {
		return INVALID_SOCKET;
	}

	for (auto rp = result; rp; rp = rp->ai_next) {
	   // Create a socket
	   auto sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
	   if (sock == INVALID_SOCKET) {
		  continue;
	   }

	   // Make 'reuse address' option available
	   int yes = 1;
	   setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char*)&yes, sizeof(yes));

	   // bind or connect
	   if (fn(sock, *rp)) {
		  freeaddrinfo(result);
		  return sock;
	   }

	   close_socket(sock);
	}

	freeaddrinfo(result);
	return INVALID_SOCKET;
}

inline void set_nonblocking(socket_t sock, bool nonblocking)
{
#ifdef _WIN32
	auto flags = nonblocking ? 1UL : 0UL;
	ioctlsocket(sock, FIONBIO, &flags);
#else
	auto flags = fcntl(sock, F_GETFL, 0);
	fcntl(sock, F_SETFL, nonblocking ? (flags | O_NONBLOCK) : (flags & (~O_NONBLOCK)));
#endif
}

inline bool is_connection_error()
{
#ifdef _WIN32
	return WSAGetLastError() != WSAEWOULDBLOCK;
#else
	return errno != EINPROGRESS;
#endif
}

inline std::string get_remote_addr(socket_t sock) {
	struct sockaddr_storage addr;
	socklen_t len = sizeof(addr);

	if (!getpeername(sock, (struct sockaddr*)&addr, &len)) {
		char ipstr[NI_MAXHOST];

		if (!getnameinfo((struct sockaddr*)&addr, len,
			ipstr, sizeof(ipstr), nullptr, 0, NI_NUMERICHOST)) {
			return ipstr;
		}
	}

	return std::string();
}

inline bool is_file(const std::string& path)
{
	struct stat st;
	return stat(path.c_str(), &st) >= 0 && S_ISREG(st.st_mode);
}

inline bool is_dir(const std::string& path)
{
	struct stat st;
	return stat(path.c_str(), &st) >= 0 && S_ISDIR(st.st_mode);
}

inline bool is_valid_path(const std::string& path) {
	size_t level = 0;
	size_t i = 0;

	// Skip slash
	while (i < path.size() && path[i] == '/') {
		i++;
	}

	while (i < path.size()) {
		// Read component
		auto beg = i;
		while (i < path.size() && path[i] != '/') {
			i++;
		}

		auto len = i - beg;
		assert(len > 0);

		if (!path.compare(beg, len, ".")) {
			;
		} else if (!path.compare(beg, len, "..")) {
			if (level == 0) {
				return false;
			}
			level--;
		} else {
			level++;
		}

		// Skip slash
		while (i < path.size() && path[i] == '/') {
			i++;
		}
	}

	return true;
}

inline void read_file(const std::string& path, std::string& out)
{
	std::ifstream fs(path, std::ios_base::binary);
	fs.seekg(0, std::ios_base::end);
	auto size = fs.tellg();
	fs.seekg(0);
	out.resize(static_cast<size_t>(size));
	fs.read(&out[0], size);
}

inline std::string file_extension(const std::string& path)
{
	boost::smatch m;
	auto pat = boost::regex("\\.([a-zA-Z0-9]+)$");
	if (boost::regex_search(path, m, pat)) {
		return m[1].str();
	}
	return std::string();
}

inline const char* find_content_type(const std::string& path)
{
	auto ext = file_extension(path);
	if (ext == "txt") {
		return "text/plain";
	} else if (ext == "html") {
		return "text/html";
	} else if (ext == "css") {
		return "text/css";
	} else if (ext == "jpeg" || ext == "jpg") {
		return "image/jpg";
	} else if (ext == "png") {
		return "image/png";
	} else if (ext == "gif") {
		return "image/gif";
	} else if (ext == "svg") {
		return "image/svg+xml";
	} else if (ext == "ico") {
		return "image/x-icon";
	} else if (ext == "json") {
		return "application/json";
	} else if (ext == "pdf") {
		return "application/pdf";
	} else if (ext == "js") {
		return "application/javascript";
	} else if (ext == "xml") {
		return "application/xml";
	} else if (ext == "xhtml") {
		return "application/xhtml+xml";
	}
	return nullptr;
}

inline const char* status_message(int status)
{
	switch (status) {
	case 200: return "OK";
	case 301: return "Moved Permanently";
	case 302: return "Found";
	case 303: return "See Other";
	case 304: return "Not Modified";
	case 400: return "Bad Request";
	case 403: return "Forbidden";
	case 404: return "Not Found";
	case 415: return "Unsupported Media Type";
	default:
		case 500: return "Internal Server Error";
	}
}

inline bool has_header(const Headers& headers, const char* key)
{
	return headers.find(key) != headers.end();
}

inline const char* get_header_value(
	const Headers& headers, const char* key, const char* def = nullptr)
{
	auto it = headers.find(key);
	if (it != headers.end()) {
		return it->second.c_str();
	}
	return def;
}

inline int get_header_value_int(const Headers& headers, const char* key, int def = 0)
{
	auto it = headers.find(key);
	if (it != headers.end()) {
		return std::stoi(it->second);
	}
	return def;
}

inline bool read_headers(Stream& strm, Headers& headers)
{
	static boost::regex re(R"((.+?):\s*(.+?)\s*\r\n)");

	const auto bufsiz = 2048;
	char buf[bufsiz];

	stream_line_reader reader(strm, buf, bufsiz);

	for (;;) {
		if (!reader.getline()) {
			return false;
		}
		if (!strcmp(reader.ptr(), "\r\n")) {
			break;
		}
		boost::cmatch m;
		if (boost::regex_match(reader.ptr(), m, re)) {
			auto key = std::string(m[1]);
			auto val = std::string(m[2]);
			headers.emplace(key, val);
		}
	}

	return true;
}

inline bool read_content_with_length(Stream& strm, std::string& out, size_t len, Progress progress)
{
	out.assign(len, 0);
	size_t r = 0;
	while (r < len){
		auto n = strm.read(&out[r], len - r);
		if (n <= 0) {
			return false;
		}

		r += n;

		if (progress) {
			if (!progress(r, len)) {
				return false;
			}
		}
	}

	return true;
}

inline bool read_content_without_length(Stream& strm, std::string& out)
{
	for (;;) {
		char byte;
		auto n = strm.read(&byte, 1);
		if (n < 0) {
			return false;
		} else if (n == 0) {
			return true;
		}
		out += byte;
	}

	return true;
}

inline bool read_content_chunked(Stream& strm, std::string& out)
{
	const auto bufsiz = 16;
	char buf[bufsiz];

	stream_line_reader reader(strm, buf, bufsiz);

	if (!reader.getline()) {
		return false;
	}

	auto chunk_len = std::stoi(reader.ptr(), 0, 16);

	while (chunk_len > 0){
		std::string chunk;
		if (!read_content_with_length(strm, chunk, chunk_len, nullptr)) {
			return false;
		}

		if (!reader.getline()) {
			return false;
		}

		if (strcmp(reader.ptr(), "\r\n")) {
			break;
		}

		out += chunk;

		if (!reader.getline()) {
			return false;
		}

		chunk_len = std::stoi(reader.ptr(), 0, 16);
	}

	if (chunk_len == 0) {
		// Reader terminator after chunks
		if (!reader.getline() || strcmp(reader.ptr(), "\r\n"))
			return false;
	}

	return true;
}

template <typename T>
bool read_content(Stream& strm, T& x, Progress progress = Progress())
{
	if (has_header(x.headers, "Content-Length")) {
		auto len = get_header_value_int(x.headers, "Content-Length", 0);
		if (len == 0) {
			const auto& encoding = get_header_value(x.headers, "Transfer-Encoding", "");
			if (!strcasecmp(encoding, "chunked")) {
				return read_content_chunked(strm, x.body);
			}
		}
		return read_content_with_length(strm, x.body, len, progress);
	} else {
		const auto& encoding = get_header_value(x.headers, "Transfer-Encoding", "");
		if (!strcasecmp(encoding, "chunked")) {
			return read_content_chunked(strm, x.body);
		}
		return read_content_without_length(strm, x.body);
	}
	return true;
}

template <typename T>
inline void write_headers(Stream& strm, const T& info)
{
	for (const auto& x: info.headers) {
		strm.write_format("%s: %s\r\n", x.first.c_str(), x.second.c_str());
	}
	strm.write("\r\n");
}

inline std::string encode_url(const std::string& s)
{
	std::string result;

	for (auto i = 0; s[i]; i++) {
		switch (s[i]) {
		case ' ':  result += "+"; break;
		case '\'': result += "%27"; break;
		case ',':  result += "%2C"; break;
		case ':':  result += "%3A"; break;
		case ';':  result += "%3B"; break;
		default:
			auto c = static_cast<uint8_t>(s[i]);
			if (c >= 0x80) {
				result += '%';
				char hex[4];
				size_t len = snprintf(hex, sizeof(hex) - 1, "%02X", c);
				assert(len == 2);
				result.append(hex, len);
			} else {
				result += s[i];
			}
			break;
		}
   }

	return result;
}

inline bool is_hex(char c, int& v)
{
	if (0x20 <= c && isdigit(c)) {
		v = c - '0';
		return true;
	} else if ('A' <= c && c <= 'F') {
		v = c - 'A' + 10;
		return true;
	} else if ('a' <= c && c <= 'f') {
		v = c - 'a' + 10;
		return true;
	}
	return false;
}

inline bool from_hex_to_i(const std::string& s, size_t i, size_t cnt, int& val)
{
	if (i >= s.size()) {
		return false;
	}

	val = 0;
	for (; cnt; i++, cnt--) {
		if (!s[i]) {
			return false;
		}
		int v = 0;
		if (is_hex(s[i], v)) {
			val = val * 16 + v;
		} else {
			return false;
		}
	}
	return true;
}

inline std::string from_i_to_hex(uint64_t n)
{
	const char *charset = "0123456789abcdef";
	std::string ret;
	do {
		ret = charset[n & 15] + ret;
		n >>= 4;
	} while (n > 0);
	return ret;
}

inline size_t to_utf8(int code, char* buff)
{
	if (code < 0x0080) {
		buff[0] = (code & 0x7F);
		return 1;
	} else if (code < 0x0800) {
		buff[0] = (0xC0 | ((code >> 6) & 0x1F));
		buff[1] = (0x80 | (code & 0x3F));
		return 2;
	} else if (code < 0xD800) {
		buff[0] = (0xE0 | ((code >> 12) & 0xF));
		buff[1] = (0x80 | ((code >> 6) & 0x3F));
		buff[2] = (0x80 | (code & 0x3F));
		return 3;
	} else if (code < 0xE000)  { // D800 - DFFF is invalid...
		return 0;
	} else if (code < 0x10000) {
		buff[0] = (0xE0 | ((code >> 12) & 0xF));
		buff[1] = (0x80 | ((code >> 6) & 0x3F));
		buff[2] = (0x80 | (code & 0x3F));
		return 3;
	} else if (code < 0x110000) {
		buff[0] = (0xF0 | ((code >> 18) & 0x7));
		buff[1] = (0x80 | ((code >> 12) & 0x3F));
		buff[2] = (0x80 | ((code >> 6) & 0x3F));
		buff[3] = (0x80 | (code & 0x3F));
		return 4;
	}

	// NOTREACHED
	return 0;
}

inline std::string decode_url(const std::string& s)
{
	std::string result;

	for (size_t i = 0; i < s.size(); i++) {
		if (s[i] == '%' && i + 1 < s.size()) {
			if (s[i + 1] == 'u') {
				int val = 0;
				if (from_hex_to_i(s, i + 2, 4, val)) {
					// 4 digits Unicode codes
					char buff[4];
					size_t len = to_utf8(val, buff);
					if (len > 0) {
						result.append(buff, len);
					}
					i += 5; // 'u0000'
				} else {
					result += s[i];
				}
			} else {
				int val = 0;
				if (from_hex_to_i(s, i + 1, 2, val)) {
					// 2 digits hex codes
					result += val;
					i += 2; // '00'
				} else {
					result += s[i];
				}
			}
		} else if (s[i] == '+') {
			result += ' ';
		} else {
			result += s[i];
		}
	}

	return result;
}

inline void parse_query_text(const std::string& s, Params& params)
{
	split(&s[0], &s[s.size()], '&', [&](const char* b, const char* e) {
		std::string key;
		std::string val;
		split(b, e, '=', [&](const char* b, const char* e) {
			if (key.empty()) {
				key.assign(b, e);
			} else {
				val.assign(b, e);
			}
		});
		params.emplace(key, decode_url(val));
	});
}

inline bool parse_multipart_boundary(const std::string& content_type, std::string& boundary)
{
	auto pos = content_type.find("boundary=");
	if (pos == std::string::npos) {
		return false;
	}

	boundary = content_type.substr(pos + 9);
	return true;
}

inline bool parse_multipart_formdata(
	const std::string& boundary, const std::string& body, MultipartFiles& files)
{
	static std::string dash = "--";
	static std::string crlf = "\r\n";

	static boost::regex re_content_type(
		"Content-Type: (.*?)", boost::regex_constants::icase);

	static boost::regex re_content_disposition(
		"Content-Disposition: form-data; name=\"(.*?)\"(?:; filename=\"(.*?)\")?",
		boost::regex_constants::icase);

	auto dash_boundary = dash + boundary;

	auto pos = body.find(dash_boundary);
	if (pos != 0) {
		return false;
	}

	pos += dash_boundary.size();

	auto next_pos = body.find(crlf, pos);
	if (next_pos == std::string::npos) {
		return false;
	}

	pos = next_pos + crlf.size();

	while (pos < body.size()) {
		next_pos = body.find(crlf, pos);
		if (next_pos == std::string::npos) {
			return false;
		}

		std::string name;
		MultipartFile file;

		auto header = body.substr(pos, (next_pos - pos));

		while (pos != next_pos) {
			boost::smatch m;
			if (boost::regex_match(header, m, re_content_type)) {
				file.content_type = m[1];
			} else if (boost::regex_match(header, m, re_content_disposition)) {
				name = m[1];
				file.filename = m[2];
			}

			pos = next_pos + crlf.size();

			next_pos = body.find(crlf, pos);
			if (next_pos == std::string::npos) {
				return false;
			}

			header = body.substr(pos, (next_pos - pos));
		}

		pos = next_pos + crlf.size();

		next_pos = body.find(crlf + dash_boundary, pos);

		if (next_pos == std::string::npos) {
			return false;
		}

		file.offset = pos;
		file.length = next_pos - pos;

		pos = next_pos + crlf.size() + dash_boundary.size();

		next_pos = body.find(crlf, pos);
		if (next_pos == std::string::npos) {
			return false;
		}

		files.emplace(name, file);

		pos = next_pos + crlf.size();
	}

	return true;
}

inline std::string to_lower(const char* beg, const char* end)
{
	std::string out;
	auto it = beg;
	while (it != end) {
		out += ::tolower(*it);
		it++;
	}
	return out;
}

inline void make_range_header_core(std::string&) {}

template<typename uint64_t>
inline void make_range_header_core(std::string& field, uint64_t value)
{
	if (!field.empty()) {
		field += ", ";
	}
	field += std::to_string(value) + "-";
}

template<typename uint64_t, typename... Args>
inline void make_range_header_core(std::string& field, uint64_t value1, uint64_t value2, Args... args)
{
	if (!field.empty()) {
		field += ", ";
	}
	field += std::to_string(value1) + "-" + std::to_string(value2);
	make_range_header_core(field, args...);
}

#ifdef CPPHTTPLIB_ZLIB_SUPPORT
inline bool can_compress(const std::string& content_type) {
	return !content_type.find("text/") ||
		content_type == "image/svg+xml" ||
		content_type == "application/javascript" ||
		content_type == "application/json" ||
		content_type == "application/xml" ||
		content_type == "application/xhtml+xml";
}

inline void compress(std::string& content)
{
	z_stream strm;
	strm.zalloc = Z_NULL;
	strm.zfree = Z_NULL;
	strm.opaque = Z_NULL;

	auto ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY);
	if (ret != Z_OK) {
		return;
	}

	strm.avail_in = content.size();
	strm.next_in = (Bytef *)content.data();

	std::string compressed;

	const auto bufsiz = 16384;
	char buff[bufsiz];
	do {
		strm.avail_out = bufsiz;
		strm.next_out = (Bytef *)buff;
		deflate(&strm, Z_FINISH);
		compressed.append(buff, bufsiz - strm.avail_out);
	} while (strm.avail_out == 0);

	content.swap(compressed);

	deflateEnd(&strm);
}

inline void decompress(std::string& content)
{
	z_stream strm;
	strm.zalloc = Z_NULL;
	strm.zfree = Z_NULL;
	strm.opaque = Z_NULL;

	// 15 is the value of wbits, which should be at the maximum possible value to ensure
	// that any gzip stream can be decoded. The offset of 16 specifies that the stream
	// to decompress will be formatted with a gzip wrapper.
	auto ret = inflateInit2(&strm, 16 + 15);
	if (ret != Z_OK) {
		return;
	}

	strm.avail_in = content.size();
	strm.next_in = (Bytef *)content.data();

	std::string decompressed;

	const auto bufsiz = 16384;
	char buff[bufsiz];
	do {
		strm.avail_out = bufsiz;
		strm.next_out = (Bytef *)buff;
		inflate(&strm, Z_NO_FLUSH);
		decompressed.append(buff, bufsiz - strm.avail_out);
	} while (strm.avail_out == 0);

	content.swap(decompressed);

	inflateEnd(&strm);
}
#endif

#ifdef _WIN32
class WSInit {
public:
	WSInit() {
		WSADATA wsaData;
		WSAStartup(0x0002, &wsaData);
	}

	~WSInit() {
		WSACleanup();
	}
};

static WSInit wsinit_;
#endif

} // namespace detail

// Header utilities
template<typename uint64_t, typename... Args>
inline std::pair<std::string, std::string> make_range_header(uint64_t value, Args... args)
{
	std::string field;
	detail::make_range_header_core(field, value, args...);
	field.insert(0, "bytes=");
	return std::make_pair("Range", field);
}

// Request implementation
inline bool Request::has_header(const char* key) const
{
	return detail::has_header(headers, key);
}

inline std::string Request::get_header_value(const char* key) const
{
	return detail::get_header_value(headers, key, "");
}

inline void Request::set_header(const char* key, const char* val)
{
	headers.emplace(key, val);
}

inline bool Request::has_param(const char* key) const
{
	return params.find(key) != params.end();
}

inline std::string Request::get_param_value(const char* key) const
{
	auto it = params.find(key);
	if (it != params.end()) {
		return it->second;
	}
	return std::string();
}

inline bool Request::has_file(const char* key) const
{
	return files.find(key) != files.end();
}

inline MultipartFile Request::get_file_value(const char* key) const
{
	auto it = files.find(key);
	if (it != files.end()) {
		return it->second;
	}
	return MultipartFile();
}

// Response implementation
inline bool Response::has_header(const char* key) const
{
	return headers.find(key) != headers.end();
}

inline std::string Response::get_header_value(const char* key) const
{
	return detail::get_header_value(headers, key, "");
}

inline void Response::set_header(const char* key, const char* val)
{
	headers.emplace(key, val);
}

inline void Response::set_redirect(const char* url)
{
	set_header("Location", url);
	status = 302;
}

inline void Response::set_content(const char* s, size_t n, const char* content_type)
{
	body.assign(s, n);
	set_header("Content-Type", content_type);
}

inline void Response::set_content(const std::string& s, const char* content_type)
{
	body = s;
	set_header("Content-Type", content_type);
}

// Rstream implementation
template <typename ...Args>
inline void Stream::write_format(const char* fmt, const Args& ...args)
{
	const auto bufsiz = 2048;
	char buf[bufsiz];

#if defined(_MSC_VER) && _MSC_VER < 1900
	auto n = _snprintf_s(buf, bufsiz, bufsiz - 1, fmt, args...);
#else
	auto n = snprintf(buf, bufsiz - 1, fmt, args...);
#endif
	if (n > 0) {
		if (n >= bufsiz - 1) {
			std::vector<char> glowable_buf(bufsiz);

			while (n >= static_cast<int>(glowable_buf.size() - 1)) {
				glowable_buf.resize(glowable_buf.size() * 2);
#if defined(_MSC_VER) && _MSC_VER < 1900
				n = _snprintf_s(&glowable_buf[0], glowable_buf.size(), glowable_buf.size() - 1, fmt, args...);
#else
				n = snprintf(&glowable_buf[0], glowable_buf.size() - 1, fmt, args...);
#endif
			}
			write(&glowable_buf[0], n);
		} else {
			write(buf, n);
		}
	}
}

// Socket stream implementation
inline SocketStream::SocketStream(socket_t sock): sock_(sock)
{
}

inline SocketStream::~SocketStream()
{
}

inline int SocketStream::read(char* ptr, size_t size)
{
	return recv(sock_, ptr, size, 0);
}

inline int SocketStream::write(const char* ptr, size_t size)
{
	return send(sock_, ptr, size, 0);
}

inline int SocketStream::write(const char* ptr)
{
	return write(ptr, strlen(ptr));
}

inline std::string SocketStream::get_remote_addr() {
	return detail::get_remote_addr(sock_);
}

// HTTP server implementation
inline Server::Server()
	: keep_alive_max_count_(5)
	, is_running_(false)
	, svr_sock_(INVALID_SOCKET)
	, running_threads_(0)
{
#ifndef _WIN32
	signal(SIGPIPE, SIG_IGN);
#endif
}

inline Server::~Server()
{
}

inline Server& Server::Get(const char* pattern, Handler handler)
{
	get_handlers_.push_back(std::make_pair(boost::regex(pattern), handler));
	return *this;
}

inline Server& Server::Post(const char* pattern, Handler handler)
{
	post_handlers_.push_back(std::make_pair(boost::regex(pattern), handler));
	return *this;
}

inline Server& Server::Put(const char* pattern, Handler handler)
{
	put_handlers_.push_back(std::make_pair(boost::regex(pattern), handler));
	return *this;
}

inline Server& Server::Delete(const char* pattern, Handler handler)
{
	delete_handlers_.push_back(std::make_pair(boost::regex(pattern), handler));
	return *this;
}

inline Server& Server::Options(const char* pattern, Handler handler)
{
	options_handlers_.push_back(std::make_pair(boost::regex(pattern), handler));
	return *this;
}

inline bool Server::set_base_dir(const char* path)
{
	if (detail::is_dir(path)) {
		base_dir_ = path;
		return true;
	}
	return false;
}

inline void Server::set_error_handler(Handler handler)
{
	error_handler_ = handler;
}

inline void Server::set_logger(Logger logger)
{
	logger_ = logger;
}

inline void Server::set_keep_alive_max_count(size_t count)
{
	keep_alive_max_count_ = count;
}

inline int Server::bind_to_any_port(const char* host, int socket_flags)
{
	return bind_internal(host, 0, socket_flags);
}

inline bool Server::listen_after_bind() {
	return listen_internal();
}

inline bool Server::listen(const char* host, int port, int socket_flags)
{
	if (bind_internal(host, port, socket_flags) < 0)
		return false;
	return listen_internal();
}

inline bool Server::is_running() const
{
	return is_running_;
}

inline void Server::stop()
{
	if (is_running_) {
		assert(svr_sock_ != INVALID_SOCKET);
		auto sock = svr_sock_;
		svr_sock_ = INVALID_SOCKET;
		detail::shutdown_socket(sock);
		detail::close_socket(sock);
	}
}

inline bool Server::parse_request_line(const char* s, Request& req)
{
	static boost::regex re("(GET|HEAD|POST|PUT|DELETE|OPTIONS) (([^?]+)(?:\\?(.+?))?) (HTTP/1\\.[01])\r\n");

	boost::cmatch m;
	if (boost::regex_match(s, m, re)) {
		req.version = std::string(m[5]);
		req.method = std::string(m[1]);
		req.target = std::string(m[2]);
		req.path = detail::decode_url(m[3]);

		// Parse query text
		auto len = std::distance(m[4].first, m[4].second);
		if (len > 0) {
			detail::parse_query_text(m[4], req.params);
		}

		return true;
	}

	return false;
}

inline void Server::write_response(Stream& strm, bool last_connection, const Request& req, Response& res)
{
	assert(res.status != -1);

	if (400 <= res.status && error_handler_) {
		error_handler_(req, res);
	}

	// Response line
	strm.write_format("HTTP/1.1 %d %s\r\n",
		res.status,
		detail::status_message(res.status));

	// Headers
	if (last_connection ||
		req.get_header_value("Connection") == "close") {
		res.set_header("Connection", "close");
	}

	if (!last_connection &&
		req.get_header_value("Connection") == "Keep-Alive") {
		res.set_header("Connection", "Keep-Alive");
	}

	if (!res.body.empty()) {
#ifdef CPPHTTPLIB_ZLIB_SUPPORT
		// TODO: 'Accpet-Encoding' has gzip, not gzip;q=0
		const auto& encodings = req.get_header_value("Accept-Encoding");
		if (encodings.find("gzip") != std::string::npos &&
			detail::can_compress(res.get_header_value("Content-Type"))) {
			detail::compress(res.body);
			res.set_header("Content-Encoding", "gzip");
		}
#endif

		if (!res.has_header("Content-Type")) {
			res.set_header("Content-Type", "text/plain");
		}

		auto length = std::to_string(res.body.size());
		res.set_header("Content-Length", length.c_str());
	} else if (res.streamcb) {
		// Streamed response
		bool chunked_response = !res.has_header("Content-Length");
		if (chunked_response)
			res.set_header("Transfer-Encoding", "chunked");
	}

	detail::write_headers(strm, res);

	// Body
	if (req.method != "HEAD") {
		if (!res.body.empty()) {
			strm.write(res.body.c_str(), res.body.size());
		} else if (res.streamcb) {
			bool chunked_response = !res.has_header("Content-Length");
			uint64_t offset = 0;
			bool data_available = true;
			while (data_available) {
				std::string chunk = res.streamcb(offset);
				offset += chunk.size();
				data_available = !chunk.empty();
				// Emit chunked response header and footer for each chunk
				if (chunked_response)
					chunk = detail::from_i_to_hex(chunk.size()) + "\r\n" + chunk + "\r\n";
				if (strm.write(chunk.c_str(), chunk.size()) < 0)
					break;  // Stop on error
			}
		}
	}

	// Log
	if (logger_) {
		logger_(req, res);
	}
}

inline bool Server::handle_file_request(Request& req, Response& res)
{
	if (!base_dir_.empty() && detail::is_valid_path(req.path)) {
		std::string path = base_dir_ + req.path;

		if (!path.empty() && path.back() == '/') {
			path += "index.html";
		}

		if (detail::is_file(path)) {
			detail::read_file(path, res.body);
			auto type = detail::find_content_type(path);
			if (type) {
				res.set_header("Content-Type", type);
			}
			res.status = 200;
			return true;
		}
	}

	return false;
}

inline socket_t Server::create_server_socket(const char* host, int port, int socket_flags) const
{
	return detail::create_socket(host, port,
		[](socket_t sock, struct addrinfo& ai) -> bool {
			if (::bind(sock, ai.ai_addr, ai.ai_addrlen)) {
				  return false;
			}
			if (::listen(sock, 5)) { // Listen through 5 channels
				return false;
			}
			return true;
		}, socket_flags);
}

inline int Server::bind_internal(const char* host, int port, int socket_flags)
{
	if (!is_valid()) {
		return -1;
	}

	svr_sock_ = create_server_socket(host, port, socket_flags);
	if (svr_sock_ == INVALID_SOCKET) {
		return -1;
	}

	if (port == 0) {
		struct sockaddr_storage address;
		socklen_t len = sizeof(address);
		if (getsockname(svr_sock_, reinterpret_cast<struct sockaddr *>(&address), &len) == -1) {
			return -1;
		}
		if (address.ss_family == AF_INET) {
		  return ntohs(reinterpret_cast<struct sockaddr_in*>(&address)->sin_port);
		} else if (address.ss_family == AF_INET6) {
		  return ntohs(reinterpret_cast<struct sockaddr_in6*>(&address)->sin6_port);
		} else {
		  return -1;
		}
	} else {
		return port;
	}
}

inline bool Server::listen_internal()
{
	auto ret = true;

	is_running_ = true;

	for (;;) {
		auto val = detail::select_read(svr_sock_, 0, 100000);

		if (val == 0) { // Timeout
			if (svr_sock_ == INVALID_SOCKET) {
				// The server socket was closed by 'stop' method.
				break;
			}
			continue;
		}

		socket_t sock = accept(svr_sock_, NULL, NULL);

		if (sock == INVALID_SOCKET) {
			if (svr_sock_ != INVALID_SOCKET) {
				detail::close_socket(svr_sock_);
				ret = false;
			} else {
				; // The server socket was closed by user.
			}
			break;
		}

		// TODO: Use thread pool...
		std::thread([=]() {
			{
				std::lock_guard<std::mutex> guard(running_threads_mutex_);
				running_threads_++;
			}

			read_and_close_socket(sock);

			{
				std::lock_guard<std::mutex> guard(running_threads_mutex_);
				running_threads_--;
			}
		}).detach();
	}

	// TODO: Use thread pool...
	for (;;) {
		std::this_thread::sleep_for(std::chrono::milliseconds(10));
		std::lock_guard<std::mutex> guard(running_threads_mutex_);
		if (!running_threads_) {
			break;
		}
	}

	is_running_ = false;

	return ret;
}

inline bool Server::routing(Request& req, Response& res)
{
	if (req.method == "GET" && handle_file_request(req, res)) {
		return true;
	}

	if (req.method == "GET" || req.method == "HEAD") {
		return dispatch_request(req, res, get_handlers_);
	} else if (req.method == "POST") {
		return dispatch_request(req, res, post_handlers_);
	} else if (req.method == "PUT") {
		return dispatch_request(req, res, put_handlers_);
	} else if (req.method == "DELETE") {
		return dispatch_request(req, res, delete_handlers_);
	} else if (req.method == "OPTIONS") {
		return dispatch_request(req, res, options_handlers_);
	}
	return false;
}

inline bool Server::dispatch_request(Request& req, Response& res, Handlers& handlers)
{
	for (const auto& x: handlers) {
		const auto& pattern = x.first;
		const auto& handler = x.second;

		if (boost::regex_match(req.path, req.matches, pattern)) {
			handler(req, res);
			return true;
		}
	}
	return false;
}

inline bool Server::process_request(Stream& strm, bool last_connection, bool& connection_close)
{
	const auto bufsiz = 2048;
	char buf[bufsiz];

	detail::stream_line_reader reader(strm, buf, bufsiz);

	// Connection has been closed on client
	if (!reader.getline()) {
		return false;
	}

	Request req;
	Response res;

	res.version = "HTTP/1.1";

	// Request line and headers
	if (!parse_request_line(reader.ptr(), req) || !detail::read_headers(strm, req.headers)) {
		res.status = 400;
		write_response(strm, last_connection, req, res);
		return true;
	}

	if (req.get_header_value("Connection") == "close") {
		connection_close = true;
	}

	req.set_header("REMOTE_ADDR", strm.get_remote_addr().c_str());

	// Body
	if (req.method == "POST" || req.method == "PUT") {
		if (!detail::read_content(strm, req)) {
			res.status = 400;
			write_response(strm, last_connection, req, res);
			return true;
		}

		const auto& content_type = req.get_header_value("Content-Type");

		if (req.get_header_value("Content-Encoding") == "gzip") {
#ifdef CPPHTTPLIB_ZLIB_SUPPORT
			detail::decompress(req.body);
#else
			res.status = 415;
			write_response(strm, last_connection, req, res);
			return true;
#endif
		}

		if (!content_type.find("application/x-www-form-urlencoded")) {
			detail::parse_query_text(req.body, req.params);
		} else if(!content_type.find("multipart/form-data")) {
			std::string boundary;
			if (!detail::parse_multipart_boundary(content_type, boundary) ||
				!detail::parse_multipart_formdata(boundary, req.body, req.files)) {
				res.status = 400;
				write_response(strm, last_connection, req, res);
				return true;
			}
		}
	}

	if (routing(req, res)) {
		if (res.status == -1) {
			res.status = 200;
		}
	} else {
		res.status = 404;
	}

	write_response(strm, last_connection, req, res);
	return true;
}

inline bool Server::is_valid() const
{
	return true;
}

inline bool Server::read_and_close_socket(socket_t sock)
{
	return detail::read_and_close_socket(
		sock,
		keep_alive_max_count_,
		[this](Stream& strm, bool last_connection, bool& connection_close) {
			return process_request(strm, last_connection, connection_close);
		});
}

// HTTP client implementation
inline Client::Client(
	const char* host, int port, time_t timeout_sec)
	: host_(host)
	, port_(port)
	, timeout_sec_(timeout_sec)
	, host_and_port_(host_ + ":" + std::to_string(port_))
{
}

inline Client::~Client()
{
}

inline bool Client::is_valid() const
{
	return true;
}

inline socket_t Client::create_client_socket() const
{
	return detail::create_socket(host_.c_str(), port_,
		[=](socket_t sock, struct addrinfo& ai) -> bool {
			detail::set_nonblocking(sock, true);

			auto ret = connect(sock, ai.ai_addr, ai.ai_addrlen);
			if (ret < 0) {
				if (detail::is_connection_error() ||
					!detail::wait_until_socket_is_ready(sock, timeout_sec_, 0)) {
					detail::close_socket(sock);
					return false;
				}
			}

			detail::set_nonblocking(sock, false);
			return true;
		});
}

inline bool Client::read_response_line(Stream& strm, Response& res)
{
	const auto bufsiz = 2048;
	char buf[bufsiz];

	detail::stream_line_reader reader(strm, buf, bufsiz);

	if (!reader.getline()) {
		return false;
	}

	const static boost::regex re("(HTTP/1\\.[01]) (\\d+?) .+\r\n");

	boost::cmatch m;
	if (boost::regex_match(reader.ptr(), m, re)) {
		res.version = std::string(m[1]);
		res.status = std::stoi(std::string(m[2]));
	}

	return true;
}

inline bool Client::send(Request& req, Response& res)
{
	if (req.path.empty()) {
		return false;
	}

	auto sock = create_client_socket();
	if (sock == INVALID_SOCKET) {
		return false;
	}

	return read_and_close_socket(sock, req, res);
}

inline void Client::write_request(Stream& strm, Request& req)
{
	auto path = detail::encode_url(req.path);

	// Request line
	strm.write_format("%s %s HTTP/1.1\r\n",
		req.method.c_str(),
		path.c_str());

	// Headers
	req.set_header("Host", host_and_port_.c_str());

	if (!req.has_header("Accept")) {
		req.set_header("Accept", "*/*");
	}

	if (!req.has_header("User-Agent")) {
		req.set_header("User-Agent", "cpp-httplib/0.2");
	}

	// TODO: Support KeepAlive connection
	// if (!req.has_header("Connection")) {
		req.set_header("Connection", "close");
	// }

	if (req.body.empty()) {
		if (req.method == "POST" || req.method == "PUT") {
			req.set_header("Content-Length", "0");
		}
	} else {
		if (!req.has_header("Content-Type")) {
			req.set_header("Content-Type", "text/plain");
		}

		auto length = std::to_string(req.body.size());
		req.set_header("Content-Length", length.c_str());
	}

	detail::write_headers(strm, req);

	// Body
	if (!req.body.empty()) {
		if (req.get_header_value("Content-Type") == "application/x-www-form-urlencoded") {
			auto str = detail::encode_url(req.body);
			strm.write(str.c_str(), str.size());
		} else {
			strm.write(req.body.c_str(), req.body.size());
		}
	}
}

inline bool Client::process_request(Stream& strm, Request& req, Response& res, bool& connection_close)
{
	// Send request
	write_request(strm, req);

	// Receive response and headers
	if (!read_response_line(strm, res) || !detail::read_headers(strm, res.headers)) {
		return false;
	}

	if (res.get_header_value("Connection") == "close" || res.version == "HTTP/1.0") {
		connection_close = true;
	}

	// Body
	if (req.method != "HEAD") {
		if (!detail::read_content(strm, res, req.progress)) {
			return false;
		}

		if (res.get_header_value("Content-Encoding") == "gzip") {
#ifdef CPPHTTPLIB_ZLIB_SUPPORT
			detail::decompress(res.body);
#else
			return false;
#endif
		}
	}

	return true;
}

inline bool Client::read_and_close_socket(socket_t sock, Request& req, Response& res)
{
	return detail::read_and_close_socket(
		sock,
		0,
		[&](Stream& strm, bool /*last_connection*/, bool& connection_close) {
			return process_request(strm, req, res, connection_close);
		});
}

inline std::shared_ptr<Response> Client::Get(const char* path, Progress progress)
{
	return Get(path, Headers(), progress);
}

inline std::shared_ptr<Response> Client::Get(const char* path, const Headers& headers, Progress progress)
{
	Request req;
	req.method = "GET";
	req.path = path;
	req.headers = headers;
	req.progress = progress;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

inline std::shared_ptr<Response> Client::Head(const char* path)
{
	return Head(path, Headers());
}

inline std::shared_ptr<Response> Client::Head(const char* path, const Headers& headers)
{
	Request req;
	req.method = "HEAD";
	req.headers = headers;
	req.path = path;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

inline std::shared_ptr<Response> Client::Post(
	const char* path, const std::string& body, const char* content_type)
{
	return Post(path, Headers(), body, content_type);
}

inline std::shared_ptr<Response> Client::Post(
	const char* path, const Headers& headers, const std::string& body, const char* content_type)
{
	Request req;
	req.method = "POST";
	req.headers = headers;
	req.path = path;

	req.headers.emplace("Content-Type", content_type);
	req.body = body;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

inline std::shared_ptr<Response> Client::Post(const char* path, const Params& params)
{
	return Post(path, Headers(), params);
}

inline std::shared_ptr<Response> Client::Post(const char* path, const Headers& headers, const Params& params)
{
	std::string query;
	for (auto it = params.begin(); it != params.end(); ++it) {
		if (it != params.begin()) {
			query += "&";
		}
		query += it->first;
		query += "=";
		query += it->second;
	}

	return Post(path, headers, query, "application/x-www-form-urlencoded");
}

inline std::shared_ptr<Response> Client::Put(
	const char* path, const std::string& body, const char* content_type)
{
	return Put(path, Headers(), body, content_type);
}

inline std::shared_ptr<Response> Client::Put(
	const char* path, const Headers& headers, const std::string& body, const char* content_type)
{
	Request req;
	req.method = "PUT";
	req.headers = headers;
	req.path = path;

	req.headers.emplace("Content-Type", content_type);
	req.body = body;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

inline std::shared_ptr<Response> Client::Delete(const char* path)
{
	return Delete(path, Headers());
}

inline std::shared_ptr<Response> Client::Delete(const char* path, const Headers& headers)
{
	Request req;
	req.method = "DELETE";
	req.path = path;
	req.headers = headers;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

inline std::shared_ptr<Response> Client::Options(const char* path)
{
	return Options(path, Headers());
}

inline std::shared_ptr<Response> Client::Options(const char* path, const Headers& headers)
{
	Request req;
	req.method = "OPTIONS";
	req.path = path;
	req.headers = headers;

	auto res = std::make_shared<Response>();

	return send(req, *res) ? res : nullptr;
}

/*
 * SSL Implementation
 */
#ifdef CPPHTTPLIB_OPENSSL_SUPPORT
namespace detail {

template <typename U, typename V, typename T>
inline bool read_and_close_socket_ssl(
	socket_t sock, size_t keep_alive_max_count,
	// TODO: OpenSSL 1.0.2 occasionally crashes...
	// The upcoming 1.1.0 is going to be thread safe.
	SSL_CTX* ctx, std::mutex& ctx_mutex,
	U SSL_connect_or_accept, V setup,
	T callback)
{
	SSL* ssl = nullptr;
	{
		std::lock_guard<std::mutex> guard(ctx_mutex);

		ssl = SSL_new(ctx);
		if (!ssl) {
			return false;
		}
	}

	auto bio = BIO_new_socket(sock, BIO_NOCLOSE);
	SSL_set_bio(ssl, bio, bio);

	setup(ssl);

	SSL_connect_or_accept(ssl);

	bool ret = false;

	if (keep_alive_max_count > 0) {
		auto count = keep_alive_max_count;
		while (count > 0 &&
			   detail::select_read(sock,
				   CPPHTTPLIB_KEEPALIVE_TIMEOUT_SECOND,
				   CPPHTTPLIB_KEEPALIVE_TIMEOUT_USECOND) > 0) {
			SSLSocketStream strm(sock, ssl);
			auto last_connection = count == 1;
			auto connection_close = false;

			ret = callback(strm, last_connection, connection_close);
			if (!ret || connection_close) {
				break;
			}

			count--;
		}
	} else {
		SSLSocketStream strm(sock, ssl);
		auto dummy_connection_close = false;
		ret = callback(strm, true, dummy_connection_close);
	}

	SSL_shutdown(ssl);

	{
		std::lock_guard<std::mutex> guard(ctx_mutex);
		SSL_free(ssl);
	}

	close_socket(sock);

	return ret;
}

class SSLInit {
public:
	SSLInit() {
		SSL_load_error_strings();
		SSL_library_init();
	}
};

static SSLInit sslinit_;

} // namespace detail

// SSL socket stream implementation
inline SSLSocketStream::SSLSocketStream(socket_t sock, SSL* ssl)
	: sock_(sock), ssl_(ssl)
{
}

inline SSLSocketStream::~SSLSocketStream()
{
}

inline int SSLSocketStream::read(char* ptr, size_t size)
{
	return SSL_read(ssl_, ptr, size);
}

inline int SSLSocketStream::write(const char* ptr, size_t size)
{
	return SSL_write(ssl_, ptr, size);
}

inline int SSLSocketStream::write(const char* ptr)
{
	return write(ptr, strlen(ptr));
}

inline std::string SSLSocketStream::get_remote_addr() {
	return detail::get_remote_addr(sock_);
}

// SSL HTTP server implementation
inline SSLServer::SSLServer(const char* cert_path, const char* private_key_path)
{
	ctx_ = SSL_CTX_new(SSLv23_server_method());

	if (ctx_) {
		SSL_CTX_set_options(ctx_,
							SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
							SSL_OP_NO_COMPRESSION |
							SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION);

		// auto ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
		// SSL_CTX_set_tmp_ecdh(ctx_, ecdh);
		// EC_KEY_free(ecdh);

		if (SSL_CTX_use_certificate_file(ctx_, cert_path, SSL_FILETYPE_PEM) != 1 ||
			SSL_CTX_use_PrivateKey_file(ctx_, private_key_path, SSL_FILETYPE_PEM) != 1) {
			SSL_CTX_free(ctx_);
			ctx_ = nullptr;
		}
	}
}

inline SSLServer::~SSLServer()
{
	if (ctx_) {
		SSL_CTX_free(ctx_);
	}
}

inline bool SSLServer::is_valid() const
{
	return ctx_;
}

inline bool SSLServer::read_and_close_socket(socket_t sock)
{
	return detail::read_and_close_socket_ssl(
		sock,
		keep_alive_max_count_,
		ctx_, ctx_mutex_,
		SSL_accept,
		[](SSL* /*ssl*/) {},
		[this](Stream& strm, bool last_connection, bool& connection_close) {
			return process_request(strm, last_connection, connection_close);
		});
}

// SSL HTTP client implementation
inline SSLClient::SSLClient(const char* host, int port, time_t timeout_sec)
	: Client(host, port, timeout_sec)
{
	ctx_ = SSL_CTX_new(SSLv23_client_method());
}

inline SSLClient::~SSLClient()
{
	if (ctx_) {
		SSL_CTX_free(ctx_);
	}
}

inline bool SSLClient::is_valid() const
{
	return ctx_;
}

inline bool SSLClient::read_and_close_socket(socket_t sock, Request& req, Response& res)
{
	return is_valid() && detail::read_and_close_socket_ssl(
		sock, 0,
		ctx_, ctx_mutex_,
		SSL_connect,
		[&](SSL* ssl) {
			SSL_set_tlsext_host_name(ssl, host_.c_str());
		},
		[&](Stream& strm, bool /*last_connection*/, bool& connection_close) {
			return process_request(strm, req, res, connection_close);
		});
}
#endif

} // namespace httplib

#endif

// vim: et ts=4 sw=4 cin cino={1s ff=unix