From: Timo Sirainen <timo.sirainen@dovecot.fi>
Date: Wed, 1 Jun 2016 15:09:48 +0000 (+0300)
Subject: lib: i_stream_get_max_buffer_size() checks also parents' max sizes
X-Git-Tag: 2.3.0.rc1~3592
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=71aed7ba87b5fd5e96e97a22d89ac025b883d60a;p=thirdparty%2Fdovecot%2Fcore.git

lib: i_stream_get_max_buffer_size() checks also parents' max sizes

This fixes i_stream_get_max_buffer_size() to work correctly with
istream-chain.
---

diff --git a/src/lib/istream.c b/src/lib/istream.c
index 9b66f79af8..83a4892d62 100644
--- a/src/lib/istream.c
+++ b/src/lib/istream.c
@@ -123,7 +123,14 @@ void i_stream_set_max_buffer_size(struct istream *stream, size_t max_size)
 
 size_t i_stream_get_max_buffer_size(struct istream *stream)
 {
-	return stream->real_stream->max_buffer_size;
+	size_t max_size = 0;
+
+	do {
+		if (max_size < stream->real_stream->max_buffer_size)
+			max_size = stream->real_stream->max_buffer_size;
+		stream = stream->real_stream->parent;
+	} while (stream != NULL);
+	return max_size;
 }
 
 void i_stream_set_return_partial_line(struct istream *stream, bool set)
diff --git a/src/lib/istream.h b/src/lib/istream.h
index 4db812005d..34f95715d1 100644
--- a/src/lib/istream.h
+++ b/src/lib/istream.h
@@ -94,9 +94,13 @@ void i_stream_sync(struct istream *stream);
    unless it's called before reading anything. */
 void i_stream_set_init_buffer_size(struct istream *stream, size_t size);
 /* Change the maximum size for stream's input buffer to grow. Useful only
-   for buffered streams (currently only file). */
+   for buffered streams (currently only file). This changes also all the
+   parent streams' max buffer size. */
 void i_stream_set_max_buffer_size(struct istream *stream, size_t max_size);
-/* Returns the current max. buffer size. */
+/* Returns the current max. buffer size for the stream. This function also
+   goesthrough all of the parent streams and returns the highest seen max
+   buffer size. This is needed because some streams (e.g. istream-chain) change
+   their max buffer size dynamically. */
 size_t i_stream_get_max_buffer_size(struct istream *stream);
 /* Enable/disable i_stream[_read]_next_line() returning the last line if it
    doesn't end with LF. */