#ifndef GNUTLS_TESTS_EAGAIN_COMMON_H
#define GNUTLS_TESTS_EAGAIN_COMMON_H

#include <errno.h>
#include <time.h>
#include <stdio.h>

#define min(x, y) ((x) < (y) ? (x) : (y))

extern const char *side;

#ifdef USE_CMOCKA
#define failure() fail()
#define client_transfer_failure(r)                               \
	{                                                        \
		fprintf(stderr, "client transfer failure: %s\n", \
			gnutls_strerror(r));                     \
		fail();                                          \
	}
#define server_transfer_failure(r)                               \
	{                                                        \
		fprintf(stderr, "server transfer failure: %s\n", \
			gnutls_strerror(r));                     \
		fail();                                          \
	}
#define switch_side(str)
#else
#define failure() fail("Handshake failed\n")
#define client_transfer_failure(r) \
	fail("client transfer failure: %s\n", gnutls_strerror(r))
#define server_transfer_failure(r) \
	fail("client transfer failure: %s\n", gnutls_strerror(r))
#define switch_side(str) side = str
#endif

#define HANDSHAKE_EXPECT(c, s, clierr, serverr)             \
	sret = cret = GNUTLS_E_AGAIN;                       \
	do {                                                \
		if (cret == GNUTLS_E_AGAIN) {               \
			switch_side("client");              \
			cret = gnutls_handshake(c);         \
			if (cret == GNUTLS_E_INTERRUPTED)   \
				cret = GNUTLS_E_AGAIN;      \
		}                                           \
		if (sret == GNUTLS_E_AGAIN) {               \
			switch_side("server");              \
			sret = gnutls_handshake(s);         \
			if (sret == GNUTLS_E_INTERRUPTED)   \
				sret = GNUTLS_E_AGAIN;      \
		}                                           \
	} while ((cret == GNUTLS_E_AGAIN ||                 \
		  (cret == 0 && sret == GNUTLS_E_AGAIN)) && \
		 (sret == GNUTLS_E_AGAIN ||                 \
		  (sret == 0 && cret == GNUTLS_E_AGAIN)));  \
	if ((clierr != -1 && cret != clierr) ||             \
	    (serverr != -1 && sret != serverr)) {           \
		fprintf(stderr, "client[%d]: %s\n", cret,   \
			gnutls_strerror(cret));             \
		fprintf(stderr, "server[%d]: %s\n", sret,   \
			gnutls_strerror(sret));             \
		failure();                                  \
	}

#define HANDSHAKE(c, s) HANDSHAKE_EXPECT(c, s, 0, 0)

#define HANDSHAKE_DTLS_EXPECT(c, s, clierr, serverr)                    \
	sret = cret = GNUTLS_E_AGAIN;                                   \
	do {                                                            \
		if (cret == GNUTLS_E_LARGE_PACKET) {                    \
			unsigned int mtu = gnutls_dtls_get_mtu(s);      \
			gnutls_dtls_set_mtu(s, mtu / 2);                \
		}                                                       \
		if (cret < 0 && gnutls_error_is_fatal(cret) == 0) {     \
			switch_side("client");                          \
			cret = gnutls_handshake(c);                     \
		}                                                       \
		if (sret == GNUTLS_E_LARGE_PACKET) {                    \
			unsigned int mtu = gnutls_dtls_get_mtu(s);      \
			gnutls_dtls_set_mtu(s, mtu / 2);                \
		}                                                       \
		if (sret < 0 && gnutls_error_is_fatal(sret) == 0) {     \
			switch_side("server");                          \
			sret = gnutls_handshake(s);                     \
		}                                                       \
	} while (((gnutls_error_is_fatal(cret) == 0 &&                  \
		   gnutls_error_is_fatal(sret) == 0)) &&                \
		 (cret < 0 || sret < 0));                               \
	if (cret != clierr || sret != serverr) {                        \
		fprintf(stderr, "client: %s\n", gnutls_strerror(cret)); \
		fprintf(stderr, "server: %s\n", gnutls_strerror(sret)); \
		failure();                                              \
	}

#define HANDSHAKE_DTLS(c, s) HANDSHAKE_DTLS_EXPECT(c, s, 0, 0)

#define HANDSHAKE(c, s) HANDSHAKE_EXPECT(c, s, 0, 0)

#define TRANSFER2(c, s, msg, msglen, buf, buflen, retry_send_with_null)        \
	{                                                                      \
		int _ret;                                                      \
		switch_side("client");                                         \
		_ret = record_send_loop(c, msg, msglen, retry_send_with_null); \
                                                                               \
		if (_ret < 0)                                                  \
			client_transfer_failure(_ret);                         \
                                                                               \
		do {                                                           \
			do {                                                   \
				switch_side("server");                         \
				_ret = gnutls_record_recv(s, buf, buflen);     \
			} while (_ret == GNUTLS_E_AGAIN);                      \
			if (_ret <= 0) {                                       \
				server_transfer_failure(_ret);                 \
			} else {                                               \
				transferred += _ret;                           \
			}                                                      \
			switch_side("server");                                 \
			_ret = record_send_loop(server, msg, msglen,           \
						retry_send_with_null);         \
			if (_ret < 0)                                          \
				server_transfer_failure(_ret);                 \
			do {                                                   \
				switch_side("client");                         \
				_ret = gnutls_record_recv(client, buf,         \
							  buflen);             \
			} while (_ret == GNUTLS_E_AGAIN);                      \
			if (_ret <= 0) {                                       \
				client_transfer_failure(_ret);                 \
			} else {                                               \
				if (msglen != _ret ||                          \
				    memcmp(buf, msg, msglen) != 0) {           \
					failure();                             \
				}                                              \
				/* echo back */                                \
				switch_side("client");                         \
				_ret = record_send_loop(client, buf, msglen,   \
							retry_send_with_null); \
				if (_ret < 0)                                  \
					client_transfer_failure(_ret);         \
				transferred += _ret;                           \
			}                                                      \
		} while (transferred < 70000);                                 \
	}

#define EMPTY_BUF(s, c, buf, buflen)                                    \
	{                                                               \
		switch_side("client");                                  \
		int _ret = 0;                                           \
		while ((_ret == GNUTLS_E_AGAIN && to_server_len > 0) || \
		       to_server_len > 0) {                             \
			switch_side("server");                          \
			_ret = gnutls_record_recv(s, buf, buflen);      \
		}                                                       \
		if (_ret < 0 && _ret != GNUTLS_E_AGAIN) {               \
			server_transfer_failure(_ret);                  \
		}                                                       \
		switch_side("server");                                  \
		_ret = 0;                                               \
		while ((to_client_len > 0 && _ret == GNUTLS_E_AGAIN) || \
		       to_client_len > 0) {                             \
			switch_side("client");                          \
			_ret = gnutls_record_recv(client, buf, buflen); \
		}                                                       \
		if (_ret < 0 && _ret != GNUTLS_E_AGAIN) {               \
			client_transfer_failure(_ret);                  \
		}                                                       \
	}

#define TRANSFER(c, s, msg, msglen, buf, buflen)      \
	TRANSFER2(c, s, msg, msglen, buf, buflen, 0); \
	TRANSFER2(c, s, msg, msglen, buf, buflen, 1)

static char to_server[64 * 1024];
static size_t to_server_len = 0;

static char to_client[64 * 1024];
static size_t to_client_len = 0;

#ifdef RANDOMIZE
#define RETURN_RND_EAGAIN(session)                           \
	unsigned int rnd = time(0);                          \
	if (rnd++ % 3 == 0) {                                \
		gnutls_transport_set_errno(session, EAGAIN); \
		return -1;                                   \
	}
#else
#define RETURN_RND_EAGAIN(session)
#endif

#ifndef IGNORE_PUSH
static ssize_t client_push(gnutls_transport_ptr_t tr, const void *data,
			   size_t len)
{
	size_t newlen;
	RETURN_RND_EAGAIN(tr);

	len = min(len, sizeof(to_server) - to_server_len);

	newlen = to_server_len + len;
	memcpy(to_server + to_server_len, data, len);
	to_server_len = newlen;
#ifdef EAGAIN_DEBUG
	fprintf(stderr, "eagain: pushed %d bytes to server (avail: %d)\n",
		(int)len, (int)to_server_len);
#endif
	return len;
}

#endif

static ssize_t client_pull(gnutls_transport_ptr_t tr, void *data, size_t len)
{
	RETURN_RND_EAGAIN(tr);

	if (to_client_len == 0) {
#ifdef EAGAIN_DEBUG
		fprintf(stderr,
			"eagain: Not enough data by server (asked for: %d, have: %d)\n",
			(int)len, (int)to_client_len);
#endif
		gnutls_transport_set_errno((gnutls_session_t)tr, EAGAIN);
		return -1;
	}

	len = min(len, to_client_len);

	memcpy(data, to_client, len);

	memmove(to_client, to_client + len, to_client_len - len);
	to_client_len -= len;
#ifdef EAGAIN_DEBUG
	fprintf(stderr, "eagain: pulled %d bytes by client (avail: %d)\n",
		(int)len, (int)to_client_len);
#endif
	return len;
}

static ssize_t server_pull(gnutls_transport_ptr_t tr, void *data, size_t len)
{
	//success ("server_pull len %d has %d\n", len, to_server_len);
	RETURN_RND_EAGAIN(tr);

	if (to_server_len == 0) {
#ifdef EAGAIN_DEBUG
		fprintf(stderr,
			"eagain: Not enough data by client (asked for: %d, have: %d)\n",
			(int)len, (int)to_server_len);
#endif
		gnutls_transport_set_errno((gnutls_session_t)tr, EAGAIN);
		return -1;
	}

	len = min(len, to_server_len);
#ifdef EAGAIN_DEBUG
	fprintf(stderr, "eagain: pulled %d bytes by server (avail: %d)\n",
		(int)len, (int)to_server_len);
#endif
	memcpy(data, to_server, len);

	memmove(to_server, to_server + len, to_server_len - len);
	to_server_len -= len;

	return len;
}

#ifndef IGNORE_PUSH
static ssize_t server_push(gnutls_transport_ptr_t tr, const void *data,
			   size_t len)
{
	size_t newlen;
	RETURN_RND_EAGAIN(tr);

	//  hexprint (data, len);

	len = min(len, sizeof(to_client) - to_client_len);

	newlen = to_client_len + len;
	memcpy(to_client + to_client_len, data, len);
	to_client_len = newlen;
#ifdef EAGAIN_DEBUG
	fprintf(stderr, "eagain: pushed %d bytes to client (avail: %d)\n",
		(int)len, (int)to_client_len);
#endif

#ifdef SERVER_PUSH_ADD
	SERVER_PUSH_ADD
#endif
	return len;
}

#endif

/* inline is used to avoid a gcc warning if used in mini-eagain */
inline static int server_pull_timeout_func(gnutls_transport_ptr_t ptr,
					   unsigned int ms)
{
	int ret;

	if (to_server_len > 0)
		ret = 1; /* available data */
	else
		ret = 0; /* timeout */

#ifdef EAGAIN_DEBUG
	fprintf(stderr,
		"eagain: server_pull_timeout: %d (avail: cli %d, serv %d)\n",
		ret, (int)to_client_len, (int)to_server_len);
#endif

	return ret;
}

inline static int client_pull_timeout_func(gnutls_transport_ptr_t ptr,
					   unsigned int ms)
{
	int ret;

	if (to_client_len > 0)
		ret = 1;
	else
		ret = 0;

#ifdef EAGAIN_DEBUG
	fprintf(stderr,
		"eagain: client_pull_timeout: %d (avail: cli %d, serv %d)\n",
		ret, (int)to_client_len, (int)to_server_len);
#endif

	return ret;
}

inline static void reset_buffers(void)
{
	to_server_len = 0;
	to_client_len = 0;
}

inline static int record_send_loop(gnutls_session_t session, const void *data,
				   size_t sizeofdata, int use_null_on_retry)
{
	int ret;
	const void *retry_data;
	size_t retry_sizeofdata;

	if (use_null_on_retry) {
		retry_data = 0;
		retry_sizeofdata = 0;
	} else {
		retry_data = data;
		retry_sizeofdata = sizeofdata;
	}

	ret = gnutls_record_send(session, data, sizeofdata);
	while (ret == GNUTLS_E_AGAIN) {
		ret = gnutls_record_send(session, retry_data, retry_sizeofdata);
	}

	return ret;
}

#endif /* GNUTLS_TESTS_EAGAIN_COMMON_H */