commit 3b300151438304ff9b4612746478f4a6068e1cf7 Author: Nick Mathewson nickm@torproject.org Date: Wed Sep 6 09:31:02 2017 -0400

Refactor connection_write_to_buf_impl_(); add one that takes a buf_t --- src/or/connection.c | 130 +++++++++++++++++++++++++++++++++++++--------------- src/or/connection.h | 1 + 2 files changed, 94 insertions(+), 37 deletions(-)

diff --git a/src/or/connection.c b/src/or/connection.c index e2392b52e..5bf84a1fc 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -4045,6 +4045,68 @@ connection_flush(connection_t *conn) return connection_handle_write(conn, 1); }

+/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf: + * + * Return true iff it is okay to queue bytes on <b>conn</b>'s outbuf for + * writing. + */ +static int +connection_may_write_to_buf(connection_t *conn) +{ + /* if it's marked for close, only allow write if we mean to flush it */ + if (conn->marked_for_close && !conn->hold_open_until_flushed) + return 0; + + return 1; +} + +/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf: + * + * Called when an attempt to add bytes on <b>conn</b>'s outbuf has failed; + * mark the connection and warn as appropriate. + */ +static void +connection_write_to_buf_failed(connection_t *conn) +{ + if (CONN_IS_EDGE(conn)) { + /* if it failed, it means we have our package/delivery windows set + wrong compared to our max outbuf size. close the whole circuit. */ + log_warn(LD_NET, + "write_to_buf failed. Closing circuit (fd %d).", (int)conn->s); + circuit_mark_for_close(circuit_get_by_edge_conn(TO_EDGE_CONN(conn)), + END_CIRC_REASON_INTERNAL); + } else if (conn->type == CONN_TYPE_OR) { + or_connection_t *orconn = TO_OR_CONN(conn); + log_warn(LD_NET, + "write_to_buf failed on an orconn; notifying of error " + "(fd %d)", (int)(conn->s)); + connection_or_close_for_error(orconn, 0); + } else { + log_warn(LD_NET, + "write_to_buf failed. Closing connection (fd %d).", + (int)conn->s); + connection_mark_for_close(conn); + } +} + +/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf: + * + * Called when an attempt to add bytes on <b>conn</b>'s outbuf has succeeded: + * record the number of bytes added. + */ +static void +connection_write_to_buf_commit(connection_t *conn, size_t len) +{ + /* If we receive optimistic data in the EXIT_CONN_STATE_RESOLVING + * state, we don't want to try to write it right away, since + * conn->write_event won't be set yet. Otherwise, write data from + * this conn as the socket is available. */ + if (conn->write_event) { + connection_start_writing(conn); + } + conn->outbuf_flushlen += len; +} + /** Append <b>len</b> bytes of <b>string</b> onto <b>conn</b>'s * outbuf, and ask it to start writing. * @@ -4059,58 +4121,52 @@ connection_write_to_buf_impl_,(const char *string, size_t len, { /* XXXX This function really needs to return -1 on failure. */ int r; - size_t old_datalen; if (!len && !(zlib<0)) return; - /* if it's marked for close, only allow write if we mean to flush it */ - if (conn->marked_for_close && !conn->hold_open_until_flushed) + + if (!connection_may_write_to_buf(conn)) return;

- old_datalen = buf_datalen(conn->outbuf); + size_t written; + if (zlib) { + size_t old_datalen = buf_datalen(conn->outbuf); dir_connection_t *dir_conn = TO_DIR_CONN(conn); int done = zlib < 0; CONN_LOG_PROTECT(conn, r = buf_add_compress(conn->outbuf, - dir_conn->compress_state, - string, len, done)); + dir_conn->compress_state, + string, len, done)); + written = buf_datalen(conn->outbuf) - old_datalen; } else { CONN_LOG_PROTECT(conn, r = buf_add(conn->outbuf, string, len)); + written = len; } if (r < 0) { - if (CONN_IS_EDGE(conn)) { - /* if it failed, it means we have our package/delivery windows set - wrong compared to our max outbuf size. close the whole circuit. */ - log_warn(LD_NET, - "write_to_buf failed. Closing circuit (fd %d).", (int)conn->s); - circuit_mark_for_close(circuit_get_by_edge_conn(TO_EDGE_CONN(conn)), - END_CIRC_REASON_INTERNAL); - } else if (conn->type == CONN_TYPE_OR) { - or_connection_t *orconn = TO_OR_CONN(conn); - log_warn(LD_NET, - "write_to_buf failed on an orconn; notifying of error " - "(fd %d)", (int)(conn->s)); - connection_or_close_for_error(orconn, 0); - } else { - log_warn(LD_NET, - "write_to_buf failed. Closing connection (fd %d).", - (int)conn->s); - connection_mark_for_close(conn); - } + connection_write_to_buf_failed(conn); return; } + connection_write_to_buf_commit(conn, written); +}

- /* If we receive optimistic data in the EXIT_CONN_STATE_RESOLVING - * state, we don't want to try to write it right away, since - * conn->write_event won't be set yet. Otherwise, write data from - * this conn as the socket is available. */ - if (conn->write_event) { - connection_start_writing(conn); - } - if (zlib) { - conn->outbuf_flushlen += buf_datalen(conn->outbuf) - old_datalen; - } else { - conn->outbuf_flushlen += len; - } +/** + * Add all bytes from <b>buf</b> to <b>conn</b>'s outbuf, draining them + * from <b>buf</b>. (If the connection is marked and will soon be closed, + * nothing is drained.) + */ +void +connection_buf_add_buf(connection_t *conn, buf_t *buf) +{ + tor_assert(conn); + tor_assert(buf); + size_t len = buf_datalen(buf); + if (len == 0) + return; + + if (!connection_may_write_to_buf(conn)) + return; + + buf_move_all(conn->outbuf, buf); + connection_write_to_buf_commit(conn, len); }

#define CONN_GET_ALL_TEMPLATE(var, test) \ diff --git a/src/or/connection.h b/src/or/connection.h index 57b9a4a1d..d5b05998e 100644 --- a/src/or/connection.h +++ b/src/or/connection.h @@ -155,6 +155,7 @@ connection_buf_add_compress(const char *string, size_t len, { connection_write_to_buf_impl_(string, len, TO_CONN(conn), done ? -1 : 1); } +void connection_buf_add_buf(connection_t *conn, buf_t *buf);

/* DOCDOC connection_get_inbuf_len */ static size_t connection_get_inbuf_len(connection_t *conn);