X-Git-Url: http://developer.intra2net.com/git/?p=libt2n;a=blobdiff_plain;f=src%2Fsocket_handler.cpp;h=00828860e757337e084482b3313c4286da8e172a;hp=11acc81790422af2eb9a0374c0ffb8e9e0114609;hb=517d1214577af263bb4d6821e4e7ad9ba8c94901;hpb=d535333ffe637c9e547e68b792f334c229641520 diff --git a/src/socket_handler.cpp b/src/socket_handler.cpp index 11acc81..0082886 100644 --- a/src/socket_handler.cpp +++ b/src/socket_handler.cpp @@ -35,6 +35,7 @@ #include #include +#include #include "socket_handler.hxx" #include "t2n_exception.hxx" @@ -45,6 +46,15 @@ using namespace std; namespace libt2n { +socket_handler::socket_handler(int _sock, socket_type_value _socket_type) +: sock(_sock) +, recv_buffer_size( default_recv_buffer_size ) +, write_block_size( default_write_block_size ) +, socket_type(_socket_type) +{ +} + + /// set options like fast reuse and keepalive every socket should have void socket_handler::set_socket_options(int sock) { @@ -96,12 +106,45 @@ bool socket_handler::is_closed() return !(r & O_ACCMODE); } + +/** + * @brief set a new size for the receive buffer. + * @param new_recv_buffer_size the new size for the receive buffer. + * + * The receive buffer determines the amount of data which is tried to read at once + * from the underlying socket. + * + * The value is normalized to be at least 512 bytes and at max 32K bytes. + */ +void socket_handler::set_recv_buffer_size(unsigned int new_recv_buffer_size) +{ + recv_buffer_size= std::max( 512u, std::min( 32u * 1024u, new_recv_buffer_size )); +} // + + +/** + * @brief set new size for the data chunks when writeing. + * @param new_write_block_size the new chunk size. + * + * The write block size determines the amound of data which is tried to write + * to the socket when data needs to be sended. + * Since writeing data is done in a loop, this does not limit the amunt of data which can + * be written. + * + * The value is normalized to be at least 512 bytes and at max 32K bytes. + */ +void socket_handler::set_write_block_size(unsigned int new_write_block_size) +{ + write_block_size= std::max( 512u, std::min( 32u * 1024u, new_write_block_size )); +} // + + /** @brief check if new data is waiting on the raw socket - @param usec_timeout wait until new data is found, max timeout usecs. + @param[in,out] usec_timeout wait until new data is found, max timeout usecs. -1: wait endless - NULL: no timeout + 0: return instantly */ -bool socket_handler::data_waiting(long long usec_timeout) +bool socket_handler::data_waiting(long long usec_timeout,long long* usec_timeout_remaining) { // just our socket fd_set active_fd_set; @@ -118,12 +161,19 @@ bool socket_handler::data_waiting(long long usec_timeout) { timeout_ptr = &tval; - // timeout von long long usec in int sec + int usec umrechnen + // convert timeout from long long usec to int sec + int usec tval.tv_sec = usec_timeout / 1000000; tval.tv_usec = usec_timeout % 1000000; } - if(select (FD_SETSIZE, &active_fd_set, NULL, NULL, timeout_ptr) > 0) + int ret=select (FD_SETSIZE, &active_fd_set, NULL, NULL, timeout_ptr); + + // return the timeout we did not use + // todo: this is linux specific according to man 2 select + if (usec_timeout > 0 && usec_timeout_remaining != NULL) + *usec_timeout_remaining=(tval.tv_sec*1000000)+tval.tv_usec; + + if (ret > 0) return true; else return false; @@ -131,14 +181,14 @@ bool socket_handler::data_waiting(long long usec_timeout) /** @brief read data from the raw socket and copy it into the provided buffer @param buffer the buffer where to append the new data - @param usec_timeout wait until new data is found, max timeout usecs. + @param[in,out] usec_timeout wait until new data is found, max timeout usecs. -1: wait endless - NULL: no timeout + 0: return instantly */ -bool socket_handler::fill_buffer(std::string& buffer, long long usec_timeout) +bool socket_handler::fill_buffer(std::string& buffer, long long usec_timeout, long long *timeout_remaining) { // fast path for timeout==0 - if (usec_timeout==0 || data_waiting(usec_timeout)) + if (usec_timeout==0 || data_waiting(usec_timeout,timeout_remaining)) return fill_buffer(buffer); else return false; @@ -184,7 +234,7 @@ bool socket_handler::fill_buffer(std::string& buffer) // Data read -> store it if (nbytes > 0) { - buffer.assign(socket_buffer,nbytes); + buffer.append(socket_buffer,nbytes); LOGSTREAM(debug,nbytes << " bytes read"); } @@ -214,7 +264,23 @@ void socket_handler::socket_write(const std::string& data) while ((rtn=::write(sock, data.data()+offset, write_size)) && rtn == -1 && (errno == EAGAIN || errno == EINTR)) { - usleep (80000); + fd_set write_set[1]; + fd_set except_set[1]; + FD_ZERO(write_set); + FD_ZERO(except_set); + FD_SET(sock, write_set); + FD_SET(sock, except_set); + // let's wait for the socket to become writable again... + //TODO: use a timeout here? + int n= ::select(sock+1, NULL, write_set, except_set, NULL); + if (n==1 && ! FD_ISSET(sock,write_set) && FD_ISSET(sock, except_set)) + { + // if we are selected but cannot write and have an exception + // we have serious trouble... + LOGSTREAM(error,"exception on socket; cannot write any more."); + //TODO: exception? + return; + } LOGSTREAM(debug,"resuming write() call after EAGAIN or EINTR"); } @@ -226,11 +292,10 @@ void socket_handler::socket_write(const std::string& data) } else if (rtn != write_size) { - LOGSTREAM(error,"write() wrote " << rtn << " bytes, should have been " + LOGSTREAM(debug,"write() wrote " << rtn << " bytes, should have been " << write_size << " (complete: " << data.size() << ")"); - // TODO: exception? - return; + write_size = rtn; } offset += write_size; @@ -239,6 +304,6 @@ void socket_handler::socket_write(const std::string& data) LOGSTREAM(debug,"wrote " << data.size() << " bytes"); return; -} +} // eo socket_handler::socket_write(const std::string&) }