/*
   +----------------------------------------------------------------------+
   | Copyright © The PHP Group and Contributors.                          |
   +----------------------------------------------------------------------+
   | This source file is subject to the Modified BSD License that is      |
   | bundled with this package in the file LICENSE, and is available      |
   | through the World Wide Web at <https://www.php.net/license/>.        |
   |                                                                      |
   | SPDX-License-Identifier: BSD-3-Clause                                |
   +----------------------------------------------------------------------+
   | Author: Stig Venaas <venaas@uninett.no>                              |
   +----------------------------------------------------------------------+
 */

#ifndef _PHP_NETWORK_H
#define _PHP_NETWORK_H

#include <php.h>

#ifndef PHP_WIN32
# undef closesocket
# define closesocket close
# include <netinet/tcp.h>
#endif

#ifndef HAVE_SHUTDOWN
#undef shutdown
#define shutdown(s,n)	/* nothing */
#endif

#ifdef PHP_WIN32
# ifdef EWOULDBLOCK
#  undef EWOULDBLOCK
# endif
# ifdef EINPROGRESS
#  undef EINPROGRESS
# endif
# define EWOULDBLOCK WSAEWOULDBLOCK
# define EINPROGRESS	WSAEWOULDBLOCK
# define fsync _commit
# define ftruncate(a, b) chsize(a, b)
#endif /* defined(PHP_WIN32) */

#ifndef EWOULDBLOCK
# define EWOULDBLOCK EAGAIN
#endif

/* This is a workaround for GCC bug 69602: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602 */
#if EAGAIN != EWOULDBLOCK
# define PHP_IS_TRANSIENT_ERROR(err) (err == EAGAIN || err == EWOULDBLOCK)
#else
# define PHP_IS_TRANSIENT_ERROR(err) (err == EAGAIN)
#endif

#ifdef PHP_WIN32
#define php_socket_errno() WSAGetLastError()
#else
#define php_socket_errno() errno
#endif

/* like strerror, but caller must efree the returned string,
 * unless buf is not NULL.
 * Also works sensibly for win32 */
BEGIN_EXTERN_C()
#ifdef PHP_WIN32
char *php_socket_strerror_s(long err, char *buf, size_t bufsize);
#else
#define php_socket_strerror_s php_socket_strerror
#endif
PHPAPI char *php_socket_strerror(long err, char *buf, size_t bufsize);
PHPAPI zend_string *php_socket_error_str(long err);
END_EXTERN_C()

#ifdef HAVE_NETINET_IN_H
# include <netinet/in.h>
#endif

#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif

#ifdef HAVE_GETHOSTBYNAME_R
#include <netdb.h>
#endif

/* These are here, rather than with the win32 counterparts above,
 * since <sys/socket.h> defines them. */
#ifndef SHUT_RD
# define SHUT_RD 0
# define SHUT_WR 1
# define SHUT_RDWR 2
#endif

#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif

#include <stddef.h>

#ifdef PHP_WIN32
typedef SOCKET php_socket_t;
#define PHP_SOCKET_FMT "%" PRIxPTR
#else
typedef int php_socket_t;
#define PHP_SOCKET_FMT "%d"
#endif

#ifdef PHP_WIN32
# define SOCK_ERR INVALID_SOCKET
# define SOCK_CONN_ERR SOCKET_ERROR
# define SOCK_RECV_ERR SOCKET_ERROR
#else
# define SOCK_ERR -1
# define SOCK_CONN_ERR -1
# define SOCK_RECV_ERR -1
#endif

#define STREAM_SOCKOP_NONE                (1 << 0)
#define STREAM_SOCKOP_SO_REUSEPORT        (1 << 1)
#define STREAM_SOCKOP_SO_BROADCAST        (1 << 2)
#define STREAM_SOCKOP_IPV6_V6ONLY         (1 << 3)
#define STREAM_SOCKOP_IPV6_V6ONLY_ENABLED (1 << 4)
#define STREAM_SOCKOP_TCP_NODELAY         (1 << 5)
#define STREAM_SOCKOP_SO_REUSEADDR        (1 << 6)
#define STREAM_SOCKOP_SO_KEEPALIVE        (1 << 7)

/* uncomment this to debug poll(2) emulation on systems that have poll(2) */
/* #define PHP_USE_POLL_2_EMULATION 1 */

#if defined(HAVE_POLL)
# if defined(HAVE_POLL_H)
#  include <poll.h>
# elif defined(HAVE_SYS_POLL_H)
#  include <sys/poll.h>
# endif
typedef struct pollfd php_pollfd;
#else
typedef struct _php_pollfd {
	php_socket_t fd;
	short events;
	short revents;
} php_pollfd;

PHPAPI int php_poll2(php_pollfd *ufds, unsigned int nfds, int timeout);

#ifndef POLLIN
# define POLLIN      0x0001    /* There is data to read */
# define POLLPRI     0x0002    /* There is urgent data to read */
# define POLLOUT     0x0004    /* Writing now will not block */
# define POLLERR     0x0008    /* Error condition */
# define POLLHUP     0x0010    /* Hung up */
# define POLLNVAL    0x0020    /* Invalid request: fd not open */
#endif

# ifndef PHP_USE_POLL_2_EMULATION
#  define PHP_USE_POLL_2_EMULATION 1
# endif
#endif

#define PHP_POLLREADABLE	(POLLIN|POLLERR|POLLHUP)

#ifndef PHP_USE_POLL_2_EMULATION
# define php_poll2(ufds, nfds, timeout)		poll(ufds, nfds, timeout)
#endif

/* timeval-to-timeout (for poll(2)) */
static inline int php_tvtoto(struct timeval *timeouttv)
{
	if (timeouttv && timeouttv->tv_sec >= 0 && timeouttv->tv_sec <= ((INT_MAX - 1000) / 1000)) {
		return (timeouttv->tv_sec * 1000) + (timeouttv->tv_usec / 1000);
	}
	return -1;
}

/* hybrid select(2)/poll(2) for a single descriptor.
 * timeouttv follows same rules as select(2), but is reduced to millisecond accuracy.
 * Returns 0 on timeout, -1 on error, or the event mask (ala poll(2)).
 */
static inline int php_pollfd_for(php_socket_t fd, int events, struct timeval *timeouttv)
{
	php_pollfd p;
	int n;

	p.fd = fd;
	p.events = events;
	p.revents = 0;

	n = php_poll2(&p, 1, php_tvtoto(timeouttv));

	if (n > 0) {
		return p.revents;
	}

	return n;
}

static inline int php_pollfd_for_ms(php_socket_t fd, int events, int timeout)
{
	php_pollfd p;
	int n;

	p.fd = fd;
	p.events = events;
	p.revents = 0;

	n = php_poll2(&p, 1, timeout);

	if (n > 0) {
		return p.revents;
	}

	return n;
}

/* emit warning and suggestion for unsafe select(2) usage */
PHPAPI void _php_emit_fd_setsize_warning(int max_fd);

static inline bool _php_check_fd_setsize(php_socket_t *max_fd, int setsize)
{
#ifdef PHP_WIN32
	(void)(max_fd); // Unused
	if (setsize + 1 >= FD_SETSIZE) {
		_php_emit_fd_setsize_warning(setsize);
		return false;
	}
#else
	(void)(setsize); // Unused
	if (*max_fd >= FD_SETSIZE) {
		_php_emit_fd_setsize_warning(*max_fd);
		*max_fd = FD_SETSIZE - 1;
		return false;
	}
#endif
	return true;
}

#ifdef PHP_WIN32
/* it is safe to FD_SET too many fd's under win32; the macro will simply ignore
 * descriptors that go beyond the default FD_SETSIZE */
# define PHP_SAFE_FD_SET(fd, set)	FD_SET(fd, set)
# define PHP_SAFE_FD_CLR(fd, set)	FD_CLR(fd, set)
# define PHP_SAFE_FD_ISSET(fd, set)	FD_ISSET(fd, set)
# define PHP_SAFE_MAX_FD(m, n)		_php_check_fd_setsize(&m, n)
#else
# define PHP_SAFE_FD_SET(fd, set)	do { if (fd < FD_SETSIZE) FD_SET(fd, set); } while(0)
# define PHP_SAFE_FD_CLR(fd, set)	do { if (fd < FD_SETSIZE) FD_CLR(fd, set); } while(0)
# define PHP_SAFE_FD_ISSET(fd, set)	((fd < FD_SETSIZE) && FD_ISSET(fd, set))
# define PHP_SAFE_MAX_FD(m, n)		_php_check_fd_setsize(&m, n)
#endif

/* A growable fd_set for stream_select(), without the FD_SETSIZE limit.
 *
 * On POSIX, fd_set is a bitset indexed by descriptor, and select() takes any nfds: the set
 * is a bitset that grows to hold the highest descriptor added.
 * On Windows, fd_set is an array of SOCKETs ({ u_int fd_count; SOCKET fd_array[]; }), and
 * select() reads fd_count of them: the set is that array, grown to hold every socket added.
 * Either way, `set` can be passed to select() as it is. */
#ifdef PHP_WIN32
typedef struct {
	u_int capacity; /* SOCKET slots in set->fd_array */
	fd_set *set;
} php_growable_fd_set;

# define PHP_GROWABLE_FD_SET_ALLOC_SIZE(cap) \
	(offsetof(fd_set, fd_array) + (size_t)(cap) * sizeof(SOCKET))

static zend_always_inline void php_growable_fd_set_init(php_growable_fd_set *s, u_int capacity)
{
	s->capacity = MAX(capacity, FD_SETSIZE);
	s->set = (fd_set *) pemalloc(PHP_GROWABLE_FD_SET_ALLOC_SIZE(s->capacity), 1);
	s->set->fd_count = 0;
}

/* Makes room for capacity sockets */
static zend_always_inline void php_growable_fd_set_reserve(php_growable_fd_set *s, u_int capacity)
{
	if (capacity > s->capacity) {
		do {
			s->capacity *= 2;
		} while (capacity > s->capacity);
		s->set = (fd_set *) perealloc(s->set, PHP_GROWABLE_FD_SET_ALLOC_SIZE(s->capacity), 1);
	}
}

static zend_always_inline void php_growable_fd_set_add(php_growable_fd_set *s, php_socket_t fd)
{
	/* Appends without the duplicate scan of winsock's FD_SET(); the set is
	 * de-duplicated in one pass later by php_growable_fd_set_sort_unique(). */
	php_growable_fd_set_reserve(s, s->set->fd_count + 1);
	s->set->fd_array[s->set->fd_count++] = fd;
}

static zend_always_inline int php_growable_fd_set_cmp(const void *a, const void *b)
{
	SOCKET x = *(const SOCKET *) a;
	SOCKET y = *(const SOCKET *) b;
	return (x > y) - (x < y);
}

/* Sorts the sockets ascending and drops duplicates. This makes select() count a
 * socket listed more than once (e.g. stream_select([$a, $a], ...)) a single time
 * - as the POSIX bitset does - and lets php_growable_fd_set_isset() binary-search
 * instead of scanning, so a whole stream_select() call is O(n log n), not O(n^2). */
static zend_always_inline void php_growable_fd_set_sort_unique(php_growable_fd_set *s)
{
	u_int n = s->set->fd_count;
	if (n < 2) {
		return;
	}
	qsort(s->set->fd_array, n, sizeof(SOCKET), php_growable_fd_set_cmp);
	u_int w = 1;
	for (u_int r = 1; r < n; r++) {
		if (s->set->fd_array[r] != s->set->fd_array[w - 1]) {
			s->set->fd_array[w++] = s->set->fd_array[r];
		}
	}
	s->set->fd_count = w;
}

/* Binary search; the set must have been sorted by php_growable_fd_set_sort_unique(). */
static zend_always_inline bool php_growable_fd_set_isset(const php_growable_fd_set *s, php_socket_t fd)
{
	SOCKET target = (SOCKET) fd;
	u_int lo = 0, hi = s->set->fd_count;
	while (lo < hi) {
		u_int mid = lo + (hi - lo) / 2;
		SOCKET v = s->set->fd_array[mid];
		if (v < target) {
			lo = mid + 1;
		} else if (v > target) {
			hi = mid;
		} else {
			return true;
		}
	}
	return false;
}

static zend_always_inline void php_growable_fd_set_zero(php_growable_fd_set *s)
{
	s->set->fd_count = 0;
}

static zend_always_inline void php_growable_fd_set_copy(php_growable_fd_set *dst, const php_growable_fd_set *src)
{
	php_growable_fd_set_reserve(dst, src->set->fd_count);
	memcpy(dst->set, src->set, PHP_GROWABLE_FD_SET_ALLOC_SIZE(src->set->fd_count));
}

static zend_always_inline void php_growable_fd_set_destroy(php_growable_fd_set *s)
{
	if (s->set) {
		pefree(s->set, 1);
		s->set = NULL;
	}
	s->capacity = 0;
}
#else
typedef struct {
	size_t size; /* bytes in set */
	fd_set *set;
} php_growable_fd_set;

/* Use the platform's fd_mask: on big-endian systems the bit positions depend on the word size */
# ifdef NFDBITS
typedef fd_mask php_growable_fd_mask;
#  define PHP_GROWABLE_FD_SET_WORD_BITS NFDBITS
# else
typedef unsigned long php_growable_fd_mask;
#  define PHP_GROWABLE_FD_SET_WORD_BITS (CHAR_BIT * sizeof(unsigned long))
# endif
/* select() operates on whole words so the size must be a multiple of sizeof(php_growable_fd_mask) */
# define PHP_GROWABLE_FD_SET_SIZE(nfds) (ZEND_MM_ALIGNED_SIZE_EX((size_t)(nfds), PHP_GROWABLE_FD_SET_WORD_BITS) / CHAR_BIT)

static zend_always_inline void php_growable_fd_set_init(php_growable_fd_set *s, unsigned int capacity)
{
	s->size = PHP_GROWABLE_FD_SET_SIZE(capacity);
	s->set = (fd_set *) ecalloc(1, s->size);
}

/* Makes room for the descriptors below capacity */
static zend_always_inline void php_growable_fd_set_reserve(php_growable_fd_set *s, unsigned int capacity)
{
	size_t size = PHP_GROWABLE_FD_SET_SIZE(capacity);
	if (size > s->size) {
		size_t old_size = s->size;
		s->size = MAX(size, old_size * 2);
		s->set = (fd_set *) erealloc(s->set, s->size);
		memset((char *) s->set + old_size, 0, s->size - old_size);
	}
}

static zend_always_inline void php_growable_fd_set_add(php_growable_fd_set *s, php_socket_t fd)
{
	php_growable_fd_set_reserve(s, fd + 1);
	((php_growable_fd_mask *) s->set)[fd / PHP_GROWABLE_FD_SET_WORD_BITS] |= (php_growable_fd_mask) (1UL << (fd % PHP_GROWABLE_FD_SET_WORD_BITS));
}

static zend_always_inline bool php_growable_fd_set_isset(const php_growable_fd_set *s, php_socket_t fd)
{
	return (size_t) fd < s->size * CHAR_BIT
		&& (((const php_growable_fd_mask *) s->set)[fd / PHP_GROWABLE_FD_SET_WORD_BITS] >> (fd % PHP_GROWABLE_FD_SET_WORD_BITS)) & 1;
}

static zend_always_inline void php_growable_fd_set_destroy(php_growable_fd_set *s)
{
	efree(s->set);
}
#endif


#define PHP_SOCK_CHUNK_SIZE	8192

#ifdef HAVE_STRUCT_SOCKADDR_STORAGE
typedef struct sockaddr_storage php_sockaddr_storage;
#else
typedef struct {
#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
		unsigned char ss_len;
		unsigned char ss_family;
#else
        unsigned short ss_family;
#endif
        char info[126];
} php_sockaddr_storage;
#endif

#define PHP_SOCKVAL_TCP_NODELAY   (1 << 0)
#define PHP_SOCKVAL_TCP_KEEPIDLE  (1 << 1)
#define PHP_SOCKVAL_TCP_KEEPCNT   (1 << 2)
#define PHP_SOCKVAL_TCP_KEEPINTVL (1 << 3)
#define PHP_SOCKVAL_SO_LINGER     (1 << 4)
#define PHP_SOCKVAL_SO_RCVBUF     (1 << 5)
#define PHP_SOCKVAL_SO_SNDBUF     (1 << 6)

#define PHP_SOCKVAL_IS_SET(sockvals, opt) ((sockvals)->mask & (opt))

typedef struct {
	unsigned int mask;
	int tcp_nodelay;
	int linger;
	int rcvbuf;
	int sndbuf;
	struct {
		int keepidle;
		int keepcnt;
		int keepintvl;
	} keepalive;
} php_sockvals;

BEGIN_EXTERN_C()
PHPAPI int php_network_getaddresses(const char *host, int socktype, struct sockaddr ***sal, zend_string **error_string);
PHPAPI void php_network_freeaddresses(struct sockaddr **sal);

PHPAPI void php_network_apply_sockvals(php_socket_t sock, const php_sockvals *sockvals);

PHPAPI php_socket_t php_network_connect_socket_to_host_ex(const char *host, unsigned short port,
		int socktype, int asynchronous, struct timeval *timeout, zend_string **error_string,
		int *error_code, const char *bindto, unsigned short bindport, long sockopts, php_sockvals *sockvals
		);

PHPAPI php_socket_t php_network_connect_socket_to_host(const char *host, unsigned short port,
		int socktype, int asynchronous, struct timeval *timeout, zend_string **error_string,
		int *error_code, const char *bindto, unsigned short bindport, long sockopts
		);

PHPAPI int php_network_connect_socket(php_socket_t sockfd,
		const struct sockaddr *addr,
		socklen_t addrlen,
		int asynchronous,
		struct timeval *timeout,
		zend_string **error_string,
		int *error_code);

#define php_connect_nonb(sock, addr, addrlen, timeout) \
	php_network_connect_socket((sock), (addr), (addrlen), 0, (timeout), NULL, NULL)

PHPAPI php_socket_t php_network_bind_socket_to_local_addr_ex(const char *host, unsigned port,
		int socktype, long sockopts, php_sockvals *sockvals, zend_string **error_string, int *error_code
		);

PHPAPI php_socket_t php_network_bind_socket_to_local_addr(const char *host, unsigned port,
		int socktype, long sockopts, zend_string **error_string, int *error_code
		);

PHPAPI php_socket_t php_network_accept_incoming_ex(php_socket_t srvsock,
		zend_string **textaddr,
		struct sockaddr **addr,
		socklen_t *addrlen,
		struct timeval *timeout,
		zend_string **error_string,
		int *error_code,
		php_sockvals *sockvals
		);

PHPAPI php_socket_t php_network_accept_incoming(php_socket_t srvsock,
		zend_string **textaddr,
		struct sockaddr **addr,
		socklen_t *addrlen,
		struct timeval *timeout,
		zend_string **error_string,
		int *error_code,
		int tcp_nodelay
		);

PHPAPI int php_network_get_sock_name(php_socket_t sock,
		zend_string **textaddr,
		struct sockaddr **addr,
		socklen_t *addrlen
		);

PHPAPI int php_network_get_peer_name(php_socket_t sock,
		zend_string **textaddr,
		struct sockaddr **addr,
		socklen_t *addrlen
		);

PHPAPI void php_any_addr(int family, php_sockaddr_storage *addr, unsigned short port);
PHPAPI socklen_t php_sockaddr_size(php_sockaddr_storage *addr);
END_EXTERN_C()

struct _php_netstream_data_t	{
	php_socket_t socket;
	bool is_blocked;
	bool timeout_event;
	struct timeval timeout;
	size_t ownsize;
};
typedef struct _php_netstream_data_t php_netstream_data_t;
PHPAPI extern const php_stream_ops php_stream_socket_ops;
extern const php_stream_ops php_stream_generic_socket_ops;
#define PHP_STREAM_IS_SOCKET	(&php_stream_socket_ops)

BEGIN_EXTERN_C()
PHPAPI php_stream *_php_stream_sock_open_from_socket(php_socket_t socket, const char *persistent_id STREAMS_DC );
/* open a connection to a host using php_hostconnect and return a stream */
PHPAPI php_stream *_php_stream_sock_open_host(const char *host, unsigned short port,
		int socktype, struct timeval *timeout, const char *persistent_id STREAMS_DC);
PHPAPI void php_network_populate_name_from_sockaddr(
		/* input address */
		struct sockaddr *sa, socklen_t sl,
		/* output readable address */
		zend_string **textaddr,
		/* output address */
		struct sockaddr **addr,
		socklen_t *addrlen
		);

PHPAPI zend_result php_network_parse_network_address_with_port(const char *addr,
		size_t addrlen, struct sockaddr *sa, socklen_t *sl);

PHPAPI struct hostent*	php_network_gethostbyname(const char *name);

PHPAPI zend_result php_set_sock_blocking(php_socket_t socketd, bool block);
END_EXTERN_C()

#define php_stream_sock_open_from_socket(socket, persistent)	_php_stream_sock_open_from_socket((socket), (persistent) STREAMS_CC)
#define php_stream_sock_open_host(host, port, socktype, timeout, persistent)	_php_stream_sock_open_host((host), (port), (socktype), (timeout), (persistent) STREAMS_CC)

/* {{{ memory debug */
#define php_stream_sock_open_from_socket_rel(socket, persistent)	_php_stream_sock_open_from_socket((socket), (persistent) STREAMS_REL_CC)
#define php_stream_sock_open_host_rel(host, port, socktype, timeout, persistent)	_php_stream_sock_open_host((host), (port), (socktype), (timeout), (persistent) STREAMS_REL_CC)
#define php_stream_sock_open_unix_rel(path, pathlen, persistent, timeval)	_php_stream_sock_open_unix((path), (pathlen), (persistent), (timeval) STREAMS_REL_CC)

/* }}} */

#ifndef MAXFQDNLEN
#define MAXFQDNLEN 255
#endif

#endif /* _PHP_NETWORK_H */