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 -errno state. */
  20         SOCKET_INTERNAL_ERROR   = -2,   /* Stop with -errno state. */
  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 *, enum connection_state 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 duplex:1;          /* Allow simultaneous reads & writes. */
 101 };
 102
 103 #define EL_PF_INET      0
 104 #define EL_PF_INET6     1
 105
 106 /* Socket management: */
 107
 108 /* Allocate and setup a socket. */
 109 struct socket *init_socket(void *conn, struct socket_operations *ops);
 110
 111 /* Reset a socket so it can be reused. XXX: Does not free() it! */
 112 void done_socket(struct socket *socket);
 113
 114 /* Closes socket if open and clear any associated handlers. */
 115 void close_socket(struct socket *socket);
 116
 117 /* Timeout handler. Will try to reconnect if possible. */
 118 void timeout_socket(struct socket *socket);
 119
 120
 121 /* Connection establishing: */
 122
 123 /* End successful connect() attempt to socket. */
 124 void complete_connect_socket(struct socket *socket, struct uri *uri,
 125                              socket_connect_T done);
 126
 127 /* Establish connection with the host and port in @uri. Storing the socket
 128  * descriptor in @socket. When the connection has been established the @done
 129  * callback will be run. @no_cache specifies whether the DNS cache should be
 130  * ignored. */
 131 void make_connection(struct socket *socket, struct uri *uri,
 132                      socket_connect_T connect_done, int no_cache);
 133
 134 /* Creates and returns a listening socket in the same IP family as the passed
 135  * ctrl_socket and stores info about the created socket in @addr. @ctrl_socket
 136  * is used for getting bind() information. */
 137 int get_pasv_socket(struct socket *ctrl_socket, struct sockaddr_storage *addr);
 138
 139 /* Try to connect to the next available address or force the connection to retry
 140  * if all has already been tried. Updates the connection state to
 141  * @connection_state. */
 142 void connect_socket(struct socket *socket, enum connection_state state);
 143
 144 /* Used by the SSL layer when negotiating. */
 145 void dns_exception(struct socket *socket);
 146
 147
 148 /* Reading and writing to sockets: */
 149
 150 /* Reads data from @socket into @buffer. Calls @done each time new data is
 151  * ready. */
 152 void read_from_socket(struct socket *socket, struct read_buffer *buffer,
 153                       enum connection_state state, socket_read_T done);
 154
 155 /* Writes @datalen bytes from @data buffer to the passed @socket. When all data
 156  * is written the @done callback will be called. */
 157 void write_to_socket(struct socket *socket,
 158                      unsigned char *data, int datalen,
 159                      enum connection_state state, socket_write_T write_done);
 160
 161 /* Send request and get response. */
 162 void request_from_socket(struct socket *socket, unsigned char *data, int datalen,
 163                          enum connection_state state, enum socket_state sock_state,
 164                          socket_read_T read_done);
 165
 166 /* Initialize a read buffer. */
 167 struct read_buffer *alloc_read_buffer(struct socket *socket);
 168
 169 /* Remove @bytes number of bytes from @buffer. */
 170 void kill_buffer_data(struct read_buffer *buffer, int bytes);
 171
 172 #endif