From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Fri, 27 Oct 2017 17:45:41 +0000 (+0300)
Subject: lib: Add i_stream_try_alloc_avoid_compress()
X-Git-Tag: 2.3.0.rc1~640
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=51d379cbc50242a13462d0fded50e013eb00cc07;p=thirdparty%2Fdovecot%2Fcore.git

lib: Add i_stream_try_alloc_avoid_compress()
---

diff --git a/src/lib/istream-private.h b/src/lib/istream-private.h
index 14b57df9ce..b86676b3aa 100644
--- a/src/lib/istream-private.h
+++ b/src/lib/istream-private.h
@@ -77,6 +77,12 @@ void i_stream_grow_buffer(struct istream_private *stream, size_t bytes);
 bool ATTR_NOWARN_UNUSED_RESULT
 i_stream_try_alloc(struct istream_private *stream,
 		   size_t wanted_size, size_t *size_r);
+/* Like i_stream_try_alloc(), but compress only if it's the only way to get
+   more space. This can be useful when stream is marked with
+   i_stream_seek_mark() */
+bool ATTR_NOWARN_UNUSED_RESULT
+i_stream_try_alloc_avoid_compress(struct istream_private *stream,
+				  size_t wanted_size, size_t *size_r);
 void *i_stream_alloc(struct istream_private *stream, size_t size);
 /* Free memory allocated by i_stream_*alloc() */
 void i_stream_free_buffer(struct istream_private *stream);
diff --git a/src/lib/istream.c b/src/lib/istream.c
index 56711082ce..dc0d3c74d5 100644
--- a/src/lib/istream.c
+++ b/src/lib/istream.c
@@ -783,6 +783,22 @@ bool i_stream_try_alloc(struct istream_private *stream,
 	return *size_r > 0;
 }
 
+bool ATTR_NOWARN_UNUSED_RESULT
+i_stream_try_alloc_avoid_compress(struct istream_private *stream,
+				  size_t wanted_size, size_t *size_r)
+{
+	size_t old_skip = stream->skip;
+
+	/* try first with skip=0, so no compression is done */
+	stream->skip = 0;
+	bool ret = i_stream_try_alloc(stream, wanted_size, size_r);
+	stream->skip = old_skip;
+	if (ret || old_skip == 0)
+		return ret;
+	/* it's full. try with compression. */
+	return i_stream_try_alloc(stream, wanted_size, size_r);
+}
+
 void *i_stream_alloc(struct istream_private *stream, size_t size)
 {
 	size_t old_size, avail_size;