From 7de13094210537ea2cc290e57481c2408e285565 Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Fri, 3 Jul 2015 23:30:54 +0200 Subject: degesch: clean up the async code a bit --- degesch.c | 142 +++++++++++++++++++++++++++++++++++--------------------------- 1 file changed, 81 insertions(+), 61 deletions(-) diff --git a/degesch.c b/degesch.c index aee0343..f548f9e 100644 --- a/degesch.c +++ b/degesch.c @@ -1065,9 +1065,9 @@ struct transport void (*cleanup) (struct server *s); /// The underlying socket may have become readable, update `read_buffer' - enum transport_io_result (*on_readable) (struct server *s); + enum transport_io_result (*try_read) (struct server *s); /// The underlying socket may have become writeable, flush `write_buffer' - enum transport_io_result (*on_writeable) (struct server *s); + enum transport_io_result (*try_write) (struct server *s); /// Return event mask to use in the poller int (*get_poll_events) (struct server *s); @@ -3203,7 +3203,9 @@ irc_send (struct server *s, const char *format, ...) print_debug ("tried sending a message to a dead server connection"); return; } - if (s->state == IRC_CLOSING) + + if (s->state == IRC_CLOSING + || s->state == IRC_HALF_CLOSED) return; va_list ap; @@ -3329,7 +3331,7 @@ initiate_quit (struct app_context *ctx) } static void -on_irc_disconnected (struct server *s) +irc_disconnect (struct server *s) { hard_assert (irc_is_connected (s)); @@ -3337,6 +3339,7 @@ on_irc_disconnected (struct server *s) if (s->transport && s->transport->cleanup) s->transport->cleanup (s); + s->transport = NULL; xclose (s->socket); s->socket = -1; @@ -3403,7 +3406,7 @@ on_irc_ping_timeout (void *user_data) { struct server *s = user_data; log_server_error (s, s->buffer, "Connection timeout"); - on_irc_disconnected (s); + irc_disconnect (s); } static void @@ -3419,74 +3422,91 @@ on_irc_timeout (void *user_data) static void irc_process_message (const struct irc_message *msg, const char *raw, void *user_data); -static void -on_irc_ready (const struct pollfd *pfd, struct server *s) +static enum transport_io_result +irc_try_read (struct server *s) { - struct transport *transport = s->transport; - enum transport_io_result result; - - if ((result = transport->on_readable (s)) == TRANSPORT_IO_ERROR) - goto error; - bool read_eof = result == TRANSPORT_IO_EOF; - - if (s->read_buffer.len >= (1 << 20)) + enum transport_io_result result = s->transport->try_read (s); + if (result == TRANSPORT_IO_OK) { - // XXX: this is stupid; if anything, count it in dependence of time - log_server_error (s, s->buffer, - "The IRC server seems to spew out data frantically"); - goto disconnect; + if (s->read_buffer.len >= (1 << 20)) + { + // XXX: this is stupid; if anything, count it in dependence of time + log_server_error (s, s->buffer, + "The IRC server seems to spew out data frantically"); + return TRANSPORT_IO_ERROR; + } + if (s->read_buffer.len) + irc_process_buffer (&s->read_buffer, irc_process_message, s); } - if (s->read_buffer.len) - irc_process_buffer (&s->read_buffer, irc_process_message, s); + return result; +} - if ((result = transport->on_writeable (s)) == TRANSPORT_IO_ERROR) - goto error; - bool write_eof = result == TRANSPORT_IO_EOF; +static enum transport_io_result +irc_try_write (struct server *s) +{ + enum transport_io_result result = s->transport->try_write (s); + if (result == TRANSPORT_IO_OK) + { + // If we're flushing the write buffer and our job is complete, we send + // an EOF to the server, changing the state to IRC_HALF_CLOSED + if (s->state == IRC_CLOSING && !s->write_buffer.len) + irc_real_shutdown (s); + } + return result; +} - // FIXME: this may probably fire multiple times if we're flushing after it, - // we should probably store this information next to the state - if (read_eof || write_eof) - log_server_error (s, s->buffer, "The IRC server closed the connection"); +static bool +irc_try_read_write (struct server *s) +{ + enum transport_io_result read_result; + enum transport_io_result write_result; + if ((read_result = irc_try_read (s)) == TRANSPORT_IO_ERROR + || (write_result = irc_try_write (s)) == TRANSPORT_IO_ERROR) + { + log_server_error (s, s->buffer, "Server connection failed"); + return false; + } - // It makes no sense to flush anything if the write needs to read - // and we receive an EOF -> disconnect right away - if (write_eof) - goto disconnect; + // FIXME: this may probably fire multiple times when we're flushing, + // we should probably store a flag next to the state + if (read_result == TRANSPORT_IO_EOF + || write_result == TRANSPORT_IO_EOF) + log_server_error (s, s->buffer, "Server closed the connection"); - // If we've been asked to flush the write buffer and our job is complete, - // we send an EOF to the server, changing the state to IRC_HALF_CLOSED - if (s->state == IRC_CLOSING && !s->write_buffer.len) - irc_real_shutdown (s); + // If the write needs to read and we receive an EOF, we can't flush + if (write_result == TRANSPORT_IO_EOF) + return false; - if (read_eof) + if (read_result == TRANSPORT_IO_EOF) { - // Both ends closed, we're done - if (s->state == IRC_HALF_CLOSED) - goto disconnect; - - // Otherwise we want to flush the write buffer + // Eventually initiate shutdown to flush the write buffer irc_shutdown (s); - // If that went well, we can disconnect now + // If there's nothing to write, we can disconnect now if (s->state == IRC_HALF_CLOSED) - goto disconnect; + return false; } + return true; +} - // XXX: shouldn't we rather wait for PONG messages? - irc_reset_connection_timeouts (s); - irc_update_poller (s, pfd); - return; - -error: - log_server_error (s, s->buffer, "Reading from the IRC server failed"); -disconnect: - on_irc_disconnected (s); +static void +on_irc_ready (const struct pollfd *pfd, struct server *s) +{ + if (irc_try_read_write (s)) + { + // XXX: shouldn't we rather wait for PONG messages? + irc_reset_connection_timeouts (s); + irc_update_poller (s, pfd); + } + else + // We don't want to keep the socket anymore + irc_disconnect (s); } // --- Plain transport --------------------------------------------------------- static enum transport_io_result -transport_plain_on_readable (struct server *s) +transport_plain_try_read (struct server *s) { struct str *buf = &s->read_buffer; ssize_t n_read; @@ -3516,7 +3536,7 @@ transport_plain_on_readable (struct server *s) } static enum transport_io_result -transport_plain_on_writeable (struct server *s) +transport_plain_try_write (struct server *s) { struct str *buf = &s->write_buffer; ssize_t n_written; @@ -3552,8 +3572,8 @@ transport_plain_get_poll_events (struct server *s) static struct transport g_transport_plain = { - .on_readable = transport_plain_on_readable, - .on_writeable = transport_plain_on_writeable, + .try_read = transport_plain_try_read, + .try_write = transport_plain_try_write, .get_poll_events = transport_plain_get_poll_events, }; @@ -3696,7 +3716,7 @@ transport_tls_cleanup (struct server *s) } static enum transport_io_result -transport_tls_on_readable (struct server *s) +transport_tls_try_read (struct server *s) { struct transport_tls_data *data = s->transport_data; if (data->ssl_tx_want_rx) @@ -3733,7 +3753,7 @@ transport_tls_on_readable (struct server *s) } static enum transport_io_result -transport_tls_on_writeable (struct server *s) +transport_tls_try_write (struct server *s) { struct transport_tls_data *data = s->transport_data; if (data->ssl_rx_want_tx) @@ -3794,8 +3814,8 @@ static struct transport g_transport_tls = { .init = transport_tls_init, .cleanup = transport_tls_cleanup, - .on_readable = transport_tls_on_readable, - .on_writeable = transport_tls_on_writeable, + .try_read = transport_tls_try_read, + .try_write = transport_tls_try_write, .get_poll_events = transport_tls_get_poll_events, .in_before_shutdown = transport_tls_in_before_shutdown, }; -- cgit v1.2.3-70-g09d2