From d8e4604b18ccdcf3d8c714ff1a265fc49321d1a0 Mon Sep 17 00:00:00 2001
From: Ryan Huffman <ryanhuffman@gmail.com>
Date: Thu, 27 Apr 2017 13:03:04 -0700
Subject: [PATCH] Fix gpu access of ktx file not being thread-safe

---
 libraries/gpu/src/gpu/Texture.h       | 8 ++++----
 libraries/gpu/src/gpu/Texture_ktx.cpp | 5 +++--
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/libraries/gpu/src/gpu/Texture.h b/libraries/gpu/src/gpu/Texture.h
index 9b23b4e695..3b8ae508eb 100755
--- a/libraries/gpu/src/gpu/Texture.h
+++ b/libraries/gpu/src/gpu/Texture.h
@@ -324,11 +324,11 @@ public:
         void reset() override { }
 
     protected:
-        std::shared_ptr<storage::FileStorage> maybeOpenFile();
+        std::shared_ptr<storage::FileStorage> maybeOpenFile() const;
 
-        std::mutex _cacheFileCreateMutex;
-        std::mutex _cacheFileWriteMutex;
-        std::weak_ptr<storage::FileStorage> _cacheFile;
+        mutable std::mutex _cacheFileCreateMutex;
+        mutable std::mutex _cacheFileWriteMutex;
+        mutable std::weak_ptr<storage::FileStorage> _cacheFile;
 
         std::string _filename;
         std::atomic<uint8_t> _minMipLevelAvailable;
diff --git a/libraries/gpu/src/gpu/Texture_ktx.cpp b/libraries/gpu/src/gpu/Texture_ktx.cpp
index efff6c7afe..d2f93c0036 100644
--- a/libraries/gpu/src/gpu/Texture_ktx.cpp
+++ b/libraries/gpu/src/gpu/Texture_ktx.cpp
@@ -128,7 +128,7 @@ KtxStorage::KtxStorage(const std::string& filename) : _filename(filename) {
     }
 }
 
-std::shared_ptr<storage::FileStorage> KtxStorage::maybeOpenFile() {
+std::shared_ptr<storage::FileStorage> KtxStorage::maybeOpenFile() const {
     std::shared_ptr<storage::FileStorage> file = _cacheFile.lock();
     if (file) {
         return file;
@@ -154,7 +154,8 @@ PixelsPointer KtxStorage::getMipFace(uint16 level, uint8 face) const {
     auto faceOffset = _ktxDescriptor->getMipFaceTexelsOffset(level, face);
     auto faceSize = _ktxDescriptor->getMipFaceTexelsSize(level, face);
     if (faceSize != 0 && faceOffset != 0) {
-        result = std::make_shared<storage::FileStorage>(_filename.c_str())->createView(faceSize, faceOffset)->toMemoryStorage();
+        auto file = maybeOpenFile();
+        result = file->createView(faceSize, faceOffset)->toMemoryStorage();
     }
     return result;
 }