From edfcd768ba394150df34d59f08765c3e061e6c72 Mon Sep 17 00:00:00 2001
From: Giulio Camuffo
Date: Sat, 26 Jan 2013 19:00:22 +0100
Subject: COMMON: Make BufferedSeekableReadStream use the buffer with SEEK_SET
 and SEEK_END

---
 common/stream.cpp | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

(limited to 'common/stream.cpp')

diff --git a/common/stream.cpp b/common/stream.cpp
index 85647bfe3a..d3cfce4066 100644
--- a/common/stream.cpp
+++ b/common/stream.cpp
@@ -379,12 +379,25 @@ BufferedSeekableReadStream::BufferedSeekableReadStream(SeekableReadStream *paren
 bool BufferedSeekableReadStream::seek(int32 offset, int whence) {
 	// If it is a "local" seek, we may get away with "seeking" around
 	// in the buffer only.
-	// Note: We could try to handle SEEK_END and SEEK_SET, too, but
-	// since they are rarely used, it seems not worth the effort.
 	_eos = false;	// seeking always cancels EOS
 
-	if (whence == SEEK_CUR && (int)_pos + offset >= 0 && _pos + offset <= _bufSize) {
-		_pos += offset;
+	int relOffset = 0;
+	switch (whence) {
+	case SEEK_SET:
+		relOffset = offset - pos();
+		break;
+	case SEEK_CUR:
+		relOffset = offset;
+		break;
+	case SEEK_END:
+		relOffset = (size() + offset) - pos();
+		break;
+	default:
+		break;
+	}
+
+	if ((int)_pos + relOffset >= 0 && _pos + relOffset <= _bufSize) {
+		_pos += relOffset;
 
 		// Note: we do not need to reset parent's eos flag here. It is
 		// sufficient that it is reset when actually seeking in the parent.
-- 
cgit v1.2.3


From b4d0a8ba66e2c99949d1fa14d801c7de77db76ba Mon Sep 17 00:00:00 2001
From: Johannes Schickel
Date: Sat, 26 Jan 2013 19:33:27 +0100
Subject: JANITORIAL: Enforce "} // End of namespace" with a single space after
 }.

---
 common/stream.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

(limited to 'common/stream.cpp')

diff --git a/common/stream.cpp b/common/stream.cpp
index 85647bfe3a..a240d4e790 100644
--- a/common/stream.cpp
+++ b/common/stream.cpp
@@ -342,7 +342,7 @@ uint32 BufferedReadStream::read(void *dataPtr, uint32 dataSize) {
 	return alreadyRead + dataSize;
 }
 
-}	// End of nameless namespace
+} // End of nameless namespace
 
 
 ReadStream *wrapBufferedReadStream(ReadStream *parentStream, uint32 bufSize, DisposeAfterUse::Flag disposeParentStream) {
@@ -400,7 +400,7 @@ bool BufferedSeekableReadStream::seek(int32 offset, int whence) {
 	return true;
 }
 
-}	// End of nameless namespace
+} // End of nameless namespace
 
 SeekableReadStream *wrapBufferedSeekableReadStream(SeekableReadStream *parentStream, uint32 bufSize, DisposeAfterUse::Flag disposeParentStream) {
 	if (parentStream)
@@ -482,7 +482,7 @@ public:
 
 };
 
-}	// End of nameless namespace
+} // End of nameless namespace
 
 WriteStream *wrapBufferedWriteStream(WriteStream *parentStream, uint32 bufSize) {
 	if (parentStream)
@@ -490,4 +490,4 @@ WriteStream *wrapBufferedWriteStream(WriteStream *parentStream, uint32 bufSize)
 	return 0;
 }
 
-}	// End of namespace Common
+} // End of namespace Common
-- 
cgit v1.2.3


From 354aa0f5f34d33e32b6f35bcbf4e6f18e2bac783 Mon Sep 17 00:00:00 2001
From: Johannes Schickel
Date: Sat, 26 Jan 2013 19:36:12 +0100
Subject: JANITORIAL: Use "End of anonymous namespace" as comment for anonymous
 namespaces.

---
 common/stream.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

(limited to 'common/stream.cpp')

diff --git a/common/stream.cpp b/common/stream.cpp
index a240d4e790..57b1b8ba93 100644
--- a/common/stream.cpp
+++ b/common/stream.cpp
@@ -342,7 +342,7 @@ uint32 BufferedReadStream::read(void *dataPtr, uint32 dataSize) {
 	return alreadyRead + dataSize;
 }
 
-} // End of nameless namespace
+} // End of anonymous namespace
 
 
 ReadStream *wrapBufferedReadStream(ReadStream *parentStream, uint32 bufSize, DisposeAfterUse::Flag disposeParentStream) {
@@ -400,7 +400,7 @@ bool BufferedSeekableReadStream::seek(int32 offset, int whence) {
 	return true;
 }
 
-} // End of nameless namespace
+} // End of anonymous namespace
 
 SeekableReadStream *wrapBufferedSeekableReadStream(SeekableReadStream *parentStream, uint32 bufSize, DisposeAfterUse::Flag disposeParentStream) {
 	if (parentStream)
@@ -482,7 +482,7 @@ public:
 
 };
 
-} // End of nameless namespace
+} // End of anonymous namespace
 
 WriteStream *wrapBufferedWriteStream(WriteStream *parentStream, uint32 bufSize) {
 	if (parentStream)
-- 
cgit v1.2.3


From 5bfd2f675620f69e23cefbaf8553cb341a9f992c Mon Sep 17 00:00:00 2001
From: Johannes Schickel
Date: Mon, 28 Jan 2013 17:30:57 +0100
Subject: COMMON: Fix successive seeks in BufferedSeekableReadStream.

This fixes the failing test case added in
da8eeb9dbed2102764b3ca0697d6882bae0402cc.

Thanks to wjp for his input on this.
---
 common/stream.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

(limited to 'common/stream.cpp')

diff --git a/common/stream.cpp b/common/stream.cpp
index 57b1b8ba93..2851b3a320 100644
--- a/common/stream.cpp
+++ b/common/stream.cpp
@@ -393,7 +393,14 @@ bool BufferedSeekableReadStream::seek(int32 offset, int whence) {
 		// just seek normally in the parent stream.
 		if (whence == SEEK_CUR)
 			offset -= (_bufSize - _pos);
-		_pos = _bufSize;
+		// We invalidate the buffer here. This assures that successive seeks
+		// do not have the chance to incorrectly think they seeked back into
+		// the buffer.
+		// Note: This does not take full advantage of the buffer. But it is
+		// a simple way to prevent nasty errors. It would be possible to take
+		// full advantage of the buffer by saving its actual start position.
+		// This seems not worth the effort for this seemingly uncommon use.
+		_pos = _bufSize = 0;
 		_parentStream->seek(offset, whence);
 	}
 
-- 
cgit v1.2.3