From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Fri, 28 Aug 2020 14:13:32 +0000 (+0300)
Subject: lib-compression: ostreams - Add asserts to clarify how buffer flushing works
X-Git-Tag: 2.3.13~260
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=154109921da276492f31fc055d7cbbb92b5f3903;p=thirdparty%2Fdovecot%2Fcore.git

lib-compression: ostreams - Add asserts to clarify how buffer flushing works

If the output buffer isn't fully sent, the flush function returns 0 early
on, before setting flushed=TRUE.
---

diff --git a/src/lib-compression/ostream-bzlib.c b/src/lib-compression/ostream-bzlib.c
index 749999017a..eef9269b10 100644
--- a/src/lib-compression/ostream-bzlib.c
+++ b/src/lib-compression/ostream-bzlib.c
@@ -107,8 +107,10 @@ static int o_stream_bzlib_send_flush(struct bzlib_ostream *zstream, bool final)
 
 	i_assert(zs->avail_in == 0);
 
-	if (zstream->flushed)
+	if (zstream->flushed) {
+		i_assert(zstream->outbuf_used == 0);
 		return 1;
+	}
 
 	if ((ret = o_stream_flush_parent_if_needed(&zstream->ostream)) <= 0)
 		return ret;
@@ -152,7 +154,8 @@ static int o_stream_bzlib_send_flush(struct bzlib_ostream *zstream, bool final)
 
 	if (final)
 		zstream->flushed = TRUE;
-	return zstream->outbuf_used == 0 ? 1 : 0;
+	i_assert(zstream->outbuf_used == 0);
+	return 1;
 }
 
 static int o_stream_bzlib_flush(struct ostream_private *stream)
diff --git a/src/lib-compression/ostream-lzma.c b/src/lib-compression/ostream-lzma.c
index b3e7b932a1..5571642258 100644
--- a/src/lib-compression/ostream-lzma.c
+++ b/src/lib-compression/ostream-lzma.c
@@ -111,8 +111,10 @@ static int o_stream_lzma_send_flush(struct lzma_ostream *zstream, bool final)
 
 	i_assert(zs->avail_in == 0);
 
-	if (zstream->flushed)
+	if (zstream->flushed) {
+		i_assert(zstream->outbuf_used == 0);
 		return 1;
+	}
 
 	if ((ret = o_stream_flush_parent_if_needed(&zstream->ostream)) <= 0)
 		return ret;
@@ -153,7 +155,8 @@ static int o_stream_lzma_send_flush(struct lzma_ostream *zstream, bool final)
 
 	if (final)
 		zstream->flushed = TRUE;
-	return zstream->outbuf_used == 0 ? 1 : 0;
+	i_assert(zstream->outbuf_used == 0);
+	return 1;
 }
 
 static int o_stream_lzma_flush(struct ostream_private *stream)
diff --git a/src/lib-compression/ostream-zlib.c b/src/lib-compression/ostream-zlib.c
index 2b584ec183..f3bf432108 100644
--- a/src/lib-compression/ostream-zlib.c
+++ b/src/lib-compression/ostream-zlib.c
@@ -177,8 +177,10 @@ o_stream_zlib_send_flush(struct zlib_ostream *zstream, bool final)
 
 	i_assert(zs->avail_in == 0);
 
-	if (zstream->flushed)
+	if (zstream->flushed) {
+		i_assert(zstream->outbuf_used == 0);
 		return 1;
+	}
 
 	if ((ret = o_stream_flush_parent_if_needed(&zstream->ostream)) <= 0)
 		return ret;
@@ -227,7 +229,8 @@ o_stream_zlib_send_flush(struct zlib_ostream *zstream, bool final)
 	}
 	if (final)
 		zstream->flushed = TRUE;
-	return zstream->outbuf_used == 0 ? 1 : 0;
+	i_assert(zstream->outbuf_used == 0);
+	return 1;
 }
 
 static int o_stream_zlib_flush(struct ostream_private *stream)
diff --git a/src/lib-compression/ostream-zstd.c b/src/lib-compression/ostream-zstd.c
index 24dc1cccb1..bc3c5e2c43 100644
--- a/src/lib-compression/ostream-zstd.c
+++ b/src/lib-compression/ostream-zstd.c
@@ -107,8 +107,10 @@ static int o_stream_zstd_send_flush(struct zstd_ostream *zstream, bool final)
 {
 	int ret;
 
-	if (zstream->flushed)
+	if (zstream->flushed) {
+		i_assert(zstream->output.pos == 0);
 		return 1;
+	}
 
 	if ((ret = o_stream_flush_parent_if_needed(&zstream->ostream)) <= 0)
 		return ret;
@@ -136,6 +138,7 @@ static int o_stream_zstd_send_flush(struct zstd_ostream *zstream, bool final)
 
 	if (final)
 		zstream->flushed = TRUE;
+	i_assert(zstream->output.pos == 0);
 	return 1;
 }