From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Fri, 27 Oct 2017 22:15:14 +0000 (+0300)
Subject: lib: Add o_stream_finish()
X-Git-Tag: 2.3.0.rc1~708
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=84717f00ddbf5cd0ebe3f285090d5e97e458e19c;p=thirdparty%2Fdovecot%2Fcore.git

lib: Add o_stream_finish()

This marks the ostream as fully finished, with no further writes coming to
it. Otherwise it behaves like o_stream_flush().

The ostream.flush() methods are supposed to write their trailer (if the
ostream has one) when they see that ostream.finished is set. These will be
implemented by the following commits.
---

diff --git a/src/lib/ostream-private.h b/src/lib/ostream-private.h
index f35d472362..d9d4fa5f7c 100644
--- a/src/lib/ostream-private.h
+++ b/src/lib/ostream-private.h
@@ -38,6 +38,7 @@ struct ostream_private {
 	void *context;
 
 	bool corked:1;
+	bool finished:1;
 	bool closing:1;
 	bool last_errors_not_checked:1;
 	bool error_handling_disabled:1;
diff --git a/src/lib/ostream.c b/src/lib/ostream.c
index 9b27293ff9..15e23d44f7 100644
--- a/src/lib/ostream.c
+++ b/src/lib/ostream.c
@@ -264,6 +264,7 @@ o_stream_sendv_int(struct ostream *stream, const struct const_iovec *iov,
 	if (total_size == 0)
 		return 0;
 
+	i_assert(!_stream->finished);
 	ret = _stream->sendv(_stream, iov, iov_count);
 	if (unlikely(ret != (ssize_t)total_size)) {
 		if (ret < 0) {
@@ -325,6 +326,12 @@ void o_stream_nsend_str(struct ostream *stream, const char *str)
 	o_stream_nsend(stream, str, strlen(str));
 }
 
+int o_stream_finish(struct ostream *stream)
+{
+	stream->real_stream->finished = TRUE;
+	return o_stream_flush(stream);
+}
+
 void o_stream_ignore_last_errors(struct ostream *stream)
 {
 	while (stream != NULL) {
@@ -355,6 +362,7 @@ o_stream_send_istream(struct ostream *outstream, struct istream *instream)
 		return OSTREAM_SEND_ISTREAM_RESULT_ERROR_OUTPUT;
 	}
 
+	i_assert(!_outstream->finished);
 	res = _outstream->send_istream(_outstream, instream);
 	switch (res) {
 	case OSTREAM_SEND_ISTREAM_RESULT_FINISHED:
@@ -417,6 +425,7 @@ int o_stream_pwrite(struct ostream *stream, const void *data, size_t size,
 		return -1;
 	}
 
+	i_assert(!stream->real_stream->finished);
 	ret = stream->real_stream->write_at(stream->real_stream,
 					    data, size, offset);
 	if (unlikely(ret < 0)) {
diff --git a/src/lib/ostream.h b/src/lib/ostream.h
index 586747f373..b93fd2d4e4 100644
--- a/src/lib/ostream.h
+++ b/src/lib/ostream.h
@@ -159,6 +159,11 @@ static inline int o_stream_nfinish(struct ostream *stream)
 {
 	return o_stream_flush(stream) < 0 ? -1 : 0;
 }
+/* Mark the ostream as finished and flush it. If the ostream has a footer,
+   it's written here. Any further write attempts to the ostream will
+   assert-crash. Returns the same as o_stream_flush(). Afterwards any calls to
+   this function are identical to o_stream_flush(). */
+int o_stream_finish(struct ostream *stream);
 /* Marks the stream's error handling as completed to avoid i_panic() on
    destroy. */
 void o_stream_ignore_last_errors(struct ostream *stream);