From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Mon, 4 Oct 2021 15:17:49 +0000 (+0300)
Subject: lib: istream-chain - Fix snapshot handling when combining two istreams
X-Git-Tag: 2.3.18~217
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=504c0e6424c46a8ad58c98577b2d6d92b6faec91;p=thirdparty%2Fdovecot%2Fcore.git

lib: istream-chain - Fix snapshot handling when combining two istreams

Snapshotting wasn't handled correctly when two (or more) istreams' contents
were combined into the same buffer.
---

diff --git a/src/lib/istream-chain.c b/src/lib/istream-chain.c
index 543a99a6e7..ea141f53e2 100644
--- a/src/lib/istream-chain.c
+++ b/src/lib/istream-chain.c
@@ -2,6 +2,7 @@
 
 #include "lib.h"
 #include "llist.h"
+#include "memarea.h"
 #include "istream-private.h"
 #include "istream-chain.h"
 
@@ -153,6 +154,9 @@ static void i_stream_chain_read_next(struct chain_istream *cstream)
 	}
 
 	if (data_size > 0) {
+		if (cstream->istream.memarea != NULL &&
+		    memarea_get_refcount(cstream->istream.memarea) > 1)
+			i_stream_memarea_detach(&cstream->istream);
 		memcpy(i_stream_alloc(&cstream->istream, data_size),
 		       data, data_size);
 		cstream->istream.pos += data_size;
@@ -319,6 +323,5 @@ struct istream *i_stream_create_chain(struct istream_chain **chain_r)
 	cstream->istream.istream.seekable = FALSE;
 
 	*chain_r = &cstream->chain;
-	return i_stream_create(&cstream->istream, NULL, -1,
-			       ISTREAM_CREATE_FLAG_NOOP_SNAPSHOT);
+	return i_stream_create(&cstream->istream, NULL, -1, 0);
 }
diff --git a/src/lib/test-istream-chain.c b/src/lib/test-istream-chain.c
index 0da4d3f9ed..162fc6522c 100644
--- a/src/lib/test-istream-chain.c
+++ b/src/lib/test-istream-chain.c
@@ -112,7 +112,17 @@ static void test_istream_chain_accumulate(void)
 
 	/* second stream */
 	i_stream_chain_append(chain, test_input2);
+	test_istream_set_size(test_input2, 0);
+	test_assert(i_stream_read_data(input, &data, &size, 10) == 0);
+	test_assert(size == 8);
+	test_istream_set_size(test_input2, 10);
 	test_assert(i_stream_read_data(input, &data, &size, 10) == 1);
+	test_assert(size == 18);
+	test_istream_set_allow_eof(test_input2, FALSE);
+	test_assert(i_stream_read(input) == 0);
+	test_istream_set_size(test_input2, 25);
+	test_istream_set_allow_eof(test_input2, TRUE);
+	test_assert(i_stream_read_data(input, &data, &size, 30) == 1);
 	test_assert(size == 33);
 	test_assert(memcmp(data, "mnopqrst"
 		"ABCDEFGHIJKLMNOPQRSTUVWXY", 33) == 0);
@@ -122,10 +132,14 @@ static void test_istream_chain_accumulate(void)
 
 	/* third stream */
 	i_stream_chain_append(chain, test_input3);
+	test_istream_set_size(test_input3, 0);
+	test_assert(i_stream_read(input) == 0);
+	test_istream_set_size(test_input3, 30);
 	test_assert(i_stream_read_data(input, &data, &size, 25) == 1);
 	test_assert(size == 51);
 	test_assert(memcmp(data, "EFGHIJKLMNOPQRSTUVWXY"
 		"!\"#$%&'()*+,-./01234567890:;<=", 51) == 0);
+	test_assert(i_stream_read(input) == 0);
 
 	/* partially skip */
 	i_stream_skip(input, 12);