diff options
| -rw-r--r-- | src/plugins/xfer/xfer-dcc.c | 193 |
1 files changed, 132 insertions, 61 deletions
diff --git a/src/plugins/xfer/xfer-dcc.c b/src/plugins/xfer/xfer-dcc.c index 644518ad9..f477f918b 100644 --- a/src/plugins/xfer/xfer-dcc.c +++ b/src/plugins/xfer/xfer-dcc.c @@ -24,6 +24,7 @@ #include <sys/types.h> #include <sys/stat.h> #include <sys/socket.h> +#include <sys/select.h> #include <netinet/in.h> #include <fcntl.h> #include <time.h> @@ -173,18 +174,61 @@ xfer_dcc_send_file_child (struct t_xfer *xfer) } /* + * Sends ACK to sender using current position in file received. + * + * Returns: + * 2: ACK sent successfully (the 4 bytes) + * 1: ACK not sent, but we consider it's not a problem + * 0: ACK not sent with socket error (DCC will be closed) + */ + +int +xfer_dcc_recv_file_send_ack (struct t_xfer *xfer) +{ + int length, num_sent, total_sent; + uint32_t pos; + const void *ptr_buf; + + pos = htonl (xfer->pos); + ptr_buf = &pos; + length = 4; + total_sent = 0; + num_sent = send (xfer->sock, ptr_buf, length, 0); + if (num_sent > 0) + total_sent += num_sent; + while (total_sent < length) + { + if ((num_sent == -1) && (errno != EAGAIN) && (errno != EWOULDBLOCK)) + return 0; + + /* if we can't send ACK now, just return with partial failure code */ + if (total_sent == 0) + return 1; + + /* at least one byte has been sent, we must send whole ACK */ + usleep (1000); + num_sent = send (xfer->sock, ptr_buf + total_sent, + length - total_sent, 0); + if (num_sent > 0) + total_sent += num_sent; + } + + /* ACK successfully sent */ + return 2; +} + +/* * Child process for receiving file with DCC protocol. */ void xfer_dcc_recv_file_child (struct t_xfer *xfer) { - int flags, num_read, num_sent, total_sent, length; + int flags, num_read, ack_enabled, ready; static char buffer[XFER_BLOCKSIZE_MAX]; - uint32_t pos; - const void *ptr_buf; time_t last_sent, new_time; - unsigned long long bytes_remaining; + unsigned long long pos_last_ack; + fd_set read_fds, write_fds, except_fds; /* first connect to sender (blocking) */ if (!weechat_network_connect_to (xfer->proxy, xfer->sock, @@ -206,80 +250,107 @@ xfer_dcc_recv_file_child (struct t_xfer *xfer) fcntl (xfer->sock, F_SETFL, flags | O_NONBLOCK); last_sent = time (NULL); + ack_enabled = 1; + pos_last_ack = 0; + while (1) { - bytes_remaining = xfer->size - xfer->pos; - num_read = recv (xfer->sock, buffer, - (bytes_remaining >= sizeof (buffer)) ? sizeof (buffer) : bytes_remaining, - 0); - if (num_read == -1) + /* wait until there is something to read on socket (or error) */ + FD_ZERO (&read_fds); + FD_ZERO (&write_fds); + FD_ZERO (&except_fds); + FD_SET (xfer->sock, &read_fds); + ready = select (xfer->sock + 1, &read_fds, &write_fds, &except_fds, NULL); + if (ready == 0) { - /* socket is temporarily not available (sender is not fast ?!) */ - if ((errno == EAGAIN) || (errno == EWOULDBLOCK) || (errno == EINTR)) - usleep (1000); - else - { - xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, - XFER_ERROR_RECV_BLOCK); - return; - } + xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, + XFER_ERROR_RECV_BLOCK); + return; } - else + + /* read maximum data on socket (until nothing is available) */ + while (1) { - if (num_read == 0) + num_read = recv (xfer->sock, buffer, sizeof (buffer), 0); + if (num_read == -1) { - xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, - XFER_ERROR_RECV_BLOCK); - return; + if ((errno != EAGAIN) && (errno != EWOULDBLOCK) && (errno != EINTR)) + { + xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, + XFER_ERROR_RECV_BLOCK); + return; + } + /* + * no more data available on socket: exit look, send ACK, and + * wait for new data on socket + */ + break; } - - if (write (xfer->file, buffer, num_read) == -1) + else { - xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, - XFER_ERROR_WRITE_LOCAL); - return; - } + if (num_read == 0) + { + xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, + XFER_ERROR_RECV_BLOCK); + return; + } - xfer->pos += (unsigned long long) num_read; - pos = htonl (xfer->pos); - - /* send the ACK (and ensure the 4 bytes are sent) */ - ptr_buf = &pos; - length = 4; - total_sent = 0; - num_sent = send (xfer->sock, ptr_buf, length, 0); - if (num_sent > 0) - total_sent += num_sent; - while (total_sent < length) - { - if ((num_sent == -1) && (errno != EAGAIN) - && (errno != EWOULDBLOCK)) + if (write (xfer->file, buffer, num_read) == -1) { xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, - XFER_ERROR_SEND_ACK); + XFER_ERROR_WRITE_LOCAL); return; } - usleep (1000); - num_sent = send (xfer->sock, ptr_buf + total_sent, - length - total_sent, 0); - if (num_sent > 0) - total_sent += num_sent; - } - /* file received ok? */ - if (xfer->pos >= xfer->size) - { - xfer_network_write_pipe (xfer, XFER_STATUS_DONE, - XFER_NO_ERROR); - return; + xfer->pos += (unsigned long long) num_read; + + /* file received ok? */ + if (xfer->pos >= xfer->size) + { + /* + * extra delay before sending ACK, otherwise the send of ACK + * may fail + */ + usleep (100000); + + /* send ACK to sender without checking return code (file OK) */ + xfer_dcc_recv_file_send_ack (xfer); + + /* set status done and return */ + xfer_network_write_pipe (xfer, XFER_STATUS_DONE, + XFER_NO_ERROR); + return; + } + + /* update status of DCC (parent process) */ + new_time = time (NULL); + if (last_sent != new_time) + { + last_sent = new_time; + xfer_network_write_pipe (xfer, XFER_STATUS_ACTIVE, + XFER_NO_ERROR); + } } + } - new_time = time (NULL); - if (last_sent != new_time) + /* send ACK to sender (if needed) */ + if (ack_enabled && (xfer->pos > pos_last_ack)) + { + switch (xfer_dcc_recv_file_send_ack (xfer)) { - last_sent = new_time; - xfer_network_write_pipe (xfer, XFER_STATUS_ACTIVE, - XFER_NO_ERROR); + case 0: + /* send error, socket down? */ + xfer_network_write_pipe (xfer, XFER_STATUS_FAILED, + XFER_ERROR_SEND_ACK); + return; + case 1: + /* send error, not fatal (buffer full?): disable ACKs */ + ack_enabled = 0; + break; + case 2: + /* send OK: save position in file as last ACK sent */ + pos_last_ack = xfer->pos; + break; } } } |