From 9b45dd2849359c1dd2405ef9f957625c9ca80b6e Mon Sep 17 00:00:00 2001
From: Max Horn <max@quendi.de>
Date: Sun, 22 Feb 2009 16:48:02 +0000
Subject: [PATCH] Modified FSDirectory::lookupCache to return a FSNode
 *pointer*, so that we can distinguish between lookup failures and invalid
 cache entries. Also changed SearchSet::createReadStreamForMember to not use
 hasFile anymore, based on the assumption that any
 Archive::createReadStreamForMember implementation has to verify whether the
 member name is valid anyway (clarified the doxygen docs accordingly)

svn-id: r38787
---
 common/archive.cpp | 36 +++++++++++++++++++++---------------
 common/archive.h   |  3 ++-
 common/fs.h        |  2 +-
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/common/archive.cpp b/common/archive.cpp
index 8add12e570d..88c56d4908e 100644
--- a/common/archive.cpp
+++ b/common/archive.cpp
@@ -99,49 +99,51 @@ FSNode FSDirectory::getFSNode() const {
 	return _node;
 }
 
-FSNode FSDirectory::lookupCache(NodeCache &cache, const String &name) const {
+FSNode *FSDirectory::lookupCache(NodeCache &cache, const String &name) const {
 	// make caching as lazy as possible
 	if (!name.empty()) {
 		ensureCached();
 
 		if (cache.contains(name))
-			return cache[name];
+			return &cache[name];
 	}
 
-	return FSNode();
+	return 0;
 }
 
 bool FSDirectory::hasFile(const String &name) {
 	if (name.empty() || !_node.isDirectory())
 		return false;
 
-	FSNode node = lookupCache(_fileCache, name);
-	return node.exists();
+	FSNode *node = lookupCache(_fileCache, name);
+	return node && node->exists();
 }
 
 ArchiveMemberPtr FSDirectory::getMember(const String &name) {
 	if (name.empty() || !_node.isDirectory())
 		return ArchiveMemberPtr();
 
-	FSNode node = lookupCache(_fileCache, name);
+	FSNode *node = lookupCache(_fileCache, name);
 
-	if (!node.exists()) {
+	if (!node || !node->exists()) {
 		warning("FSDirectory::getMember: FSNode does not exist");
 		return ArchiveMemberPtr();
-	} else if (node.isDirectory()) {
+	} else if (node->isDirectory()) {
 		warning("FSDirectory::getMember: FSNode is a directory");
 		return ArchiveMemberPtr();
 	}
 
-	return ArchiveMemberPtr(new FSNode(node));
+	return ArchiveMemberPtr(new FSNode(*node));
 }
 
 SeekableReadStream *FSDirectory::createReadStreamForMember(const String &name) const {
 	if (name.empty() || !_node.isDirectory())
 		return 0;
 
-	FSNode node = lookupCache(_fileCache, name);
-	SeekableReadStream *stream = node.createReadStream();
+	FSNode *node = lookupCache(_fileCache, name);
+	if (!node)
+		return 0;
+	SeekableReadStream *stream = node->createReadStream();
 	if (!stream)
 		warning("FSDirectory::createReadStreamForMember: Can't create stream for file '%s'", name.c_str());
 
@@ -156,8 +158,11 @@ FSDirectory *FSDirectory::getSubDirectory(const String &prefix, const String &na
 	if (name.empty() || !_node.isDirectory())
 		return 0;
 
-	FSNode node = lookupCache(_subDirCache, name);
-	return new FSDirectory(prefix, node, depth);
+	FSNode *node = lookupCache(_subDirCache, name);
+	if (!node)
+		return 0;
+
+	return new FSDirectory(prefix, *node, depth);
 }
 
 void FSDirectory::cacheDirectoryRecursive(FSNode node, int depth, const String& prefix) const {
@@ -380,8 +385,9 @@ SeekableReadStream *SearchSet::createReadStreamForMember(const String &name) con
 
 	ArchiveNodeList::iterator it = _list.begin();
 	for ( ; it != _list.end(); ++it) {
-		if (it->_arc->hasFile(name))
-			return it->_arc->createReadStreamForMember(name);
+		SeekableReadStream *stream = it->_arc->createReadStreamForMember(name);
+		if (stream)
+			return stream;
 	}
 
 	return 0;
diff --git a/common/archive.h b/common/archive.h
index a7ebb8aa75d..ba3445cc16c 100644
--- a/common/archive.h
+++ b/common/archive.h
@@ -116,7 +116,8 @@ public:
 	virtual ArchiveMemberPtr getMember(const String &name) = 0;
 
 	/**
-	 * Create a stream bound to a file in the archive.
+	 * Create a stream bound to a member in the archive. If no member with the
+	 * specified name exists, then 0 is returned.
 	 * @return the newly created input stream
 	 */
 	virtual SeekableReadStream *createReadStreamForMember(const String &name) const = 0;
diff --git a/common/fs.h b/common/fs.h
index bfbbb532e0b..1dcd07b1cf7 100644
--- a/common/fs.h
+++ b/common/fs.h
@@ -268,7 +268,7 @@ class FSDirectory : public Archive {
 	mutable int	_depth;
 
 	// look for a match
-	FSNode lookupCache(NodeCache &cache, const String &name) const;
+	FSNode *lookupCache(NodeCache &cache, const String &name) const;
 
 	// cache management
 	void cacheDirectoryRecursive(FSNode node, int depth, const String& prefix) const;