// SPDX-License-Identifier: GPL-3.0-or-later

#ifndef NETDATA_SOCKET_H
#define NETDATA_SOCKET_H

#include "../libnetdata.h"

#ifndef MAX_LISTEN_FDS
#define MAX_LISTEN_FDS 50
#endif

#define ND_CHECK_CANCELLABILITY_WHILE_WAITING_EVERY_MS 100

typedef struct listen_sockets {
    struct config *config;              // the config file to use
    const char *config_section;         // the netdata configuration section to read settings from
    const char *default_bind_to;        // the default bind to configuration string
    uint16_t default_port;              // the default port to use
    int backlog;                        // the default listen backlog to use

    size_t opened;                      // the number of sockets opened
    size_t failed;                      // the number of sockets attempted to open, but failed
    int fds[MAX_LISTEN_FDS];            // the open sockets
    char *fds_names[MAX_LISTEN_FDS];    // descriptions for the open sockets
    int fds_types[MAX_LISTEN_FDS];      // the socktype for the open sockets (SOCK_STREAM, SOCK_DGRAM)
    int fds_families[MAX_LISTEN_FDS];   // the family of the open sockets (AF_UNIX, AF_INET, AF_INET6)
    HTTP_ACL fds_acl_flags[MAX_LISTEN_FDS];  // the acl to apply to the open sockets (dashboard, badges, streaming, netdata.conf, management)
} LISTEN_SOCKETS;

char *strdup_client_description(int family, const char *protocol, const char *ip, uint16_t port);

int listen_sockets_setup(LISTEN_SOCKETS *sockets);
void listen_sockets_close(LISTEN_SOCKETS *sockets);

void foreach_entry_in_connection_string(const char *destination, bool (*callback)(char *entry, void *data), void *data);
int connect_to_this_ip46(
    int protocol,
    int socktype,
    const char *host,
    uint32_t scope_id,
    const char *service,
    struct timeval *timeout,
    bool *fallback_ipv4);
int connect_to_this(const char *definition, int default_port, struct timeval *timeout);
int connect_to_one_of(const char *destination, int default_port, struct timeval *timeout, size_t *reconnects_counter, char *connected_to, size_t connected_to_size);
int connect_to_one_of_urls(const char *destination, int default_port, struct timeval *timeout, size_t *reconnects_counter, char *connected_to, size_t connected_to_size);


#ifdef ENABLE_HTTPS
ssize_t recv_timeout(NETDATA_SSL *ssl,int sockfd, void *buf, size_t len, int flags, int timeout);
ssize_t send_timeout(NETDATA_SSL *ssl,int sockfd, void *buf, size_t len, int flags, int timeout);
int wait_on_socket_or_cancel_with_timeout(NETDATA_SSL *ssl, int fd, int timeout_ms, short int poll_events, short int *revents);
#else
ssize_t recv_timeout(int sockfd, void *buf, size_t len, int flags, int timeout);
ssize_t send_timeout(int sockfd, void *buf, size_t len, int flags, int timeout);
int wait_on_socket_or_cancel_with_timeout(int fd, int timeout_ms, short int poll_events, short int *revents);
#endif

bool fd_is_socket(int fd);
bool sock_has_output_error(int fd);

int sock_setnonblock(int fd);
int sock_delnonblock(int fd);
int sock_setreuse(int fd, int reuse);
void sock_setcloexec(int fd);
int sock_setreuse_port(int fd, int reuse);
int sock_enlarge_in(int fd);
int sock_enlarge_out(int fd);

int connection_allowed(int fd, char *client_ip, char *client_host, size_t hostsize,
                              SIMPLE_PATTERN *access_list, const char *patname, int allow_dns);
int accept_socket(int fd, int flags, char *client_ip, size_t ipsize, char *client_port, size_t portsize,
                         char *client_host, size_t hostsize, SIMPLE_PATTERN *access_list, int allow_dns);

#ifndef HAVE_ACCEPT4
int accept4(int sock, struct sockaddr *addr, socklen_t *addrlen, int flags);
#endif /* #ifndef HAVE_ACCEPT4 */

#ifdef SOCK_CLOEXEC
#define DEFAULT_SOCKET_FLAGS SOCK_CLOEXEC
#else
#define DEFAULT_SOCKET_FLAGS 0
#endif


// ----------------------------------------------------------------------------
// poll() based listener

#define POLLINFO_FLAG_SERVER_SOCKET 0x00000001
#define POLLINFO_FLAG_CLIENT_SOCKET 0x00000002
#define POLLINFO_FLAG_DONT_CLOSE    0x00000004

typedef struct poll POLLJOB;

typedef struct pollinfo {
    POLLJOB *p;             // the parent
    size_t slot;            // the slot id

    int fd;                 // the file descriptor
    int socktype;           // the client socket type
    HTTP_ACL port_acl; // the access lists permitted on this web server port (it's -1 for client sockets)
    char *client_ip;         // Max INET6_ADDRSTRLEN bytes
    char *client_port;       // Max NI_MAXSERV bytes
    char *client_host;       // Max NI_MAXHOST bytes

    time_t connected_t;     // the time the socket connected
    time_t last_received_t; // the time the socket last received data
    time_t last_sent_t;     // the time the socket last sent data

    size_t recv_count;      // the number of times the socket was ready for inbound traffic
    size_t send_count;      // the number of times the socket was ready for outbound traffic

    uint32_t flags;         // internal flags

    // callbacks for this socket
    void  (*del_callback)(struct pollinfo *pi);
    int   (*rcv_callback)(struct pollinfo *pi, short int *events);
    int   (*snd_callback)(struct pollinfo *pi, short int *events);

    // the user data
    void *data;

    // linking of free pollinfo structures
    // for quickly finding the next available
    // this is like a stack, it grows and shrinks
    // (with gaps - lower empty slots are preferred)
    struct pollinfo *next;
} POLLINFO;

struct poll {
    size_t slots;
    size_t used;
    size_t min;
    size_t max;

    size_t limit;

    time_t complete_request_timeout;
    time_t idle_timeout;
    time_t checks_every;

    time_t timer_milliseconds;
    void *timer_data;

    struct pollfd *fds;
    struct pollinfo *inf;
    struct pollinfo *first_free;

    SIMPLE_PATTERN *access_list;
    int allow_dns;

    void *(*add_callback)(POLLINFO *pi, short int *events, void *data);
    void  (*del_callback)(POLLINFO *pi);
    int   (*rcv_callback)(POLLINFO *pi, short int *events);
    int   (*snd_callback)(POLLINFO *pi, short int *events);
    void  (*tmr_callback)(void *timer_data);
};

#define pollinfo_from_slot(p, slot) (&((p)->inf[(slot)]))

int poll_default_snd_callback(POLLINFO *pi, short int *events);
int poll_default_rcv_callback(POLLINFO *pi, short int *events);
void poll_default_del_callback(POLLINFO *pi);
void *poll_default_add_callback(POLLINFO *pi, short int *events, void *data);

POLLINFO *poll_add_fd(POLLJOB *p
                             , int fd
                             , int socktype
                             , HTTP_ACL port_acl
                             , uint32_t flags
                             , const char *client_ip
                             , const char *client_port
                             , const char *client_host
                             , void *(*add_callback)(POLLINFO *pi, short int *events, void *data)
                             , void  (*del_callback)(POLLINFO *pi)
                             , int   (*rcv_callback)(POLLINFO *pi, short int *events)
                             , int   (*snd_callback)(POLLINFO *pi, short int *events)
                             , void *data
);
void poll_close_fd(POLLINFO *pi);

void poll_events(LISTEN_SOCKETS *sockets
        , void *(*add_callback)(POLLINFO *pi, short int *events, void *data)
        , void  (*del_callback)(POLLINFO *pi)
        , int   (*rcv_callback)(POLLINFO *pi, short int *events)
        , int   (*snd_callback)(POLLINFO *pi, short int *events)
        , void  (*tmr_callback)(void *timer_data)
        , bool  (*check_to_stop_callback)(void)
        , SIMPLE_PATTERN *access_list
        , int allow_dns
        , void *data
        , time_t tcp_request_timeout_seconds
        , time_t tcp_idle_timeout_seconds
        , time_t timer_milliseconds
        , void *timer_data
        , size_t max_tcp_sockets
);

#ifndef INET6_ADDRSTRLEN
#define INET6_ADDRSTRLEN 46
#endif

typedef struct socket_peers {
    struct {
        char ip[INET6_ADDRSTRLEN];
        int port;
    } local;

    struct {
        char ip[INET6_ADDRSTRLEN];
        int port;
    } peer;
} SOCKET_PEERS;

SOCKET_PEERS socket_peers(int sock_fd);
bool ip_to_hostname(const char *ip, char *dst, size_t dst_len);

#endif //NETDATA_SOCKET_H
