From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Tue, 5 Jun 2018 11:22:08 +0000 (+0300)
Subject: lib-compression: deflate ostream - Use Z_FINISH on final flush
X-Git-Tag: 2.3.9~1737
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3b9fd6391ca2ab34c324013b6567451c489e427a;p=thirdparty%2Fdovecot%2Fcore.git

lib-compression: deflate ostream - Use Z_FINISH on final flush

Nowadays we have o_stream_finish(), so we can differentiate between
intermediate flush and final flush. Using this allows istream-zlib to
cleanly see that the stream ends.
---

diff --git a/src/lib-compression/ostream-zlib.c b/src/lib-compression/ostream-zlib.c
index c34937c9bb..67584d4667 100644
--- a/src/lib-compression/ostream-zlib.c
+++ b/src/lib-compression/ostream-zlib.c
@@ -161,8 +161,7 @@ o_stream_zlib_send_chunk(struct zlib_ostream *zstream,
 
 	zstream->crc = crc32_data_more(zstream->crc, data, size);
 	zstream->bytes32 += size;
-	zstream->flushed = flush == Z_SYNC_FLUSH && zs->avail_in == 0 &&
-		zs->avail_out == sizeof(zstream->outbuf);
+	zstream->flushed = FALSE;
 	return size;
 }
 
@@ -189,8 +188,8 @@ o_stream_zlib_send_flush(struct zlib_ostream *zstream, bool final)
 	if ((ret = o_stream_zlib_send_outbuf(zstream)) <= 0)
 		return ret;
 
-	flush = !zstream->gz ? Z_SYNC_FLUSH :
-		(final ? Z_FINISH : Z_NO_FLUSH);
+	flush = final ? Z_FINISH :
+		(!zstream->gz ? Z_SYNC_FLUSH : Z_NO_FLUSH);
 
 	i_assert(zstream->outbuf_used == 0);
 	do {
@@ -222,7 +221,7 @@ o_stream_zlib_send_flush(struct zlib_ostream *zstream, bool final)
 		if (o_stream_zlib_send_gz_trailer(zstream) < 0)
 			return -1;
 	}
-	if (final || flush != Z_NO_FLUSH)
+	if (final)
 		zstream->flushed = TRUE;
 	return 0;
 }
diff --git a/src/lib-compression/test-compression.c b/src/lib-compression/test-compression.c
index 11141c0cca..2996e49e92 100644
--- a/src/lib-compression/test-compression.c
+++ b/src/lib-compression/test-compression.c
@@ -76,6 +76,7 @@ static void test_compression_handler(const struct compression_handler *handler)
 		i_stream_skip(input, size);
 	}
 	test_assert(ret == -1);
+	test_assert(input->stream_errno == 0);
 	i_stream_destroy(&input);
 	i_stream_destroy(&file_input);
 	sha1_result(&sha1, input_sha1);