src/network/socket.h

   1 #ifndef EL__NETWORK_SOCKET_H
   2 #define EL__NETWORK_SOCKET_H
   3
   4 #include <sys/types.h>
   5 #ifdef HAVE_SYS_SOCKET_H
   6 #include <sys/socket.h> /* OS/2 needs this after sys/types.h */
   7 #endif
   8
   9 #include "network/state.h"
  10
  11 struct connect_info;
  12 struct read_buffer;
  13 struct socket;
  14 struct uri;
  15
  16
  17 /* Use internally for error return values. */
  18 enum socket_error {
  19         SOCKET_SYSCALL_ERROR    = -1,   /* Retry with connection_state_for_errno(errno). */
  20         SOCKET_INTERNAL_ERROR   = -2,   /* Stop with connection_state(errno). */
  21         SOCKET_SSL_WANT_READ    = -3,   /* Try to read some more. */
  22         SOCKET_CANT_READ        = -4,   /* Retry with S_CANT_READ state. */
  23         SOCKET_CANT_WRITE       = -5,   /* Retry with S_CANT_WRITE state. */
  24 };
  25
  26 enum socket_state {
  27         /* If a zero-byte message is read prematurely the connection will be
  28          * retried with error state S_CANT_READ. */
  29         SOCKET_RETRY_ONCLOSE,
  30         /* If a zero-byte message is read flush the remaining bytes in the
  31          * buffer and tell the protocol handler to end the reading by calling
  32          * read_buffer->done(). */
  33         SOCKET_END_ONCLOSE,
  34         /* Used for signaling to protocols - via the read_buffer->done()
  35          * callback - that a zero-byte message was read. */
  36         SOCKET_CLOSED,
  37 };
  38
  39 typedef void (*socket_read_T)(struct socket *, struct read_buffer *);
  40 typedef void (*socket_write_T)(struct socket *);
  41 typedef void (*socket_connect_T)(struct socket *);
  42 typedef void (*socket_operation_T)(struct socket *, struct connection_state);
  43
  44 struct socket_operations {
  45         /* Report change in the state of the socket. */
  46         socket_operation_T set_state;
  47         /* Reset the timeout for the socket. */
  48         socket_operation_T set_timeout;
  49         /* Some system related error occurred; advise to reconnect. */
  50         socket_operation_T retry;
  51         /* A fatal error occurred, like a memory allocation failure; advise to
  52          * abort the connection. */
  53         socket_operation_T done;
  54 };
  55
  56 struct read_buffer {
  57         /* A routine called *each time new data comes in*, therefore
  58          * usually many times, not only when all the data arrives. */
  59         socket_read_T done;
  60
  61         int length;
  62         int freespace;
  63
  64         unsigned char data[1]; /* must be at end of struct */
  65 };
  66
  67 struct socket {
  68         /* The socket descriptor */
  69         int fd;
  70
  71         /* Somewhat read-specific socket state management and signaling. */
  72         enum socket_state state;
  73
  74         /* Information for resolving the connection with which the socket is
  75          * associated. */
  76         void *conn;
  77
  78         /* Information used during the connection establishing phase. */
  79         struct connect_info *connect_info;
  80
  81         /* Use for read and write buffers. */
  82         struct read_buffer *read_buffer;
  83         void *write_buffer;
  84
  85         /* Callbacks to the connection management: */
  86         struct socket_operations *ops;
  87
  88         /* Used by the request/response interface for saving the read_done
  89          * operation. */
  90         socket_read_T read_done;
  91
  92         /* For connections using SSL this is in fact (ssl_t *), but we don't
  93          * want to know. Noone cares and inclusion of SSL header files costs a
  94          * lot of compilation time. --pasky */
  95         void *ssl;
  96
  97         unsigned int protocol_family:1; /* EL_PF_INET, EL_PF_INET6 */
  98         unsigned int need_ssl:1;        /* If the socket needs SSL support */
  99         unsigned int no_tls:1;          /* Internal SSL flag. */
 100         unsigned int set_no_tls:1;      /* Was the blacklist checked yet? */
 101         unsigned int duplex:1;          /* Allow simultaneous reads & writes. */
 102 };
 103
 104 #define EL_PF_INET      0
 105 #define EL_PF_INET6     1
 106
 107 /* Socket management: */
 108
 109 /* Allocate and setup a socket. */
 110 struct socket *init_socket(void *conn, struct socket_operations *ops);
 111
 112 /* Reset a socket so it can be reused. XXX: Does not free() it! */
 113 void done_socket(struct socket *socket);
 114
 115 /* Closes socket if open and clear any associated handlers. */
 116 void close_socket(struct socket *socket);
 117
 118 /* Timeout handler. Will try to reconnect if possible. */
 119 void timeout_socket(struct socket *socket);
 120
 121
 122 /* Connection establishing: */
 123
 124 /* End successful connect() attempt to socket. */
 125 void complete_connect_socket(struct socket *socket, struct uri *uri,
 126                              socket_connect_T done);
 127
 128 /* Establish connection with the host and port in @uri. Storing the socket
 129  * descriptor in @socket. When the connection has been established the @done
 130  * callback will be run. @no_cache specifies whether the DNS cache should be
 131  * ignored. */
 132 void make_connection(struct socket *socket, struct uri *uri,
 133                      socket_connect_T connect_done, int no_cache);
 134
 135 /* Creates and returns a listening socket in the same IP family as the passed
 136  * ctrl_socket and stores info about the created socket in @addr. @ctrl_socket
 137  * is used for getting bind() information. */
 138 int get_pasv_socket(struct socket *ctrl_socket, struct sockaddr_storage *addr);
 139
 140 /* Try to connect to the next available address or force the connection to retry
 141  * if all has already been tried. Updates the connection state to
 142  * @connection_state. */
 143 void connect_socket(struct socket *socket, struct connection_state state);
 144
 145 /* Used by the SSL layer when negotiating. */
 146 void dns_exception(struct socket *socket);
 147
 148
 149 /* Reading and writing to sockets: */
 150
 151 /* Reads data from @socket into @buffer. Calls @done each time new data is
 152  * ready. */
 153 void read_from_socket(struct socket *socket, struct read_buffer *buffer,
 154                       struct connection_state state, socket_read_T done);
 155
 156 /* Writes @datalen bytes from @data buffer to the passed @socket. When all data
 157  * is written the @done callback will be called. */
 158 void write_to_socket(struct socket *socket,
 159                      unsigned char *data, int datalen,
 160                      struct connection_state state, socket_write_T write_done);
 161
 162 /* Send request and get response. */
 163 void request_from_socket(struct socket *socket, unsigned char *data, int datalen,
 164                          struct connection_state state, enum socket_state sock_state,
 165                          socket_read_T read_done);
 166
 167 /* Initialize a read buffer. */
 168 struct read_buffer *alloc_read_buffer(struct socket *socket);
 169
 170 /* Remove @bytes number of bytes from @buffer. */
 171 void kill_buffer_data(struct read_buffer *buffer, int bytes);
 172
 173 #endif