From 52c4aef72125ed834c444e3a1868aab827621bdb Mon Sep 17 00:00:00 2001
From: SamGondelman <samuel_gondelman@alumni.brown.edu>
Date: Fri, 15 Dec 2017 16:23:53 -0800
Subject: [PATCH] keep _cacheFile alive

---
 libraries/gpu/src/gpu/Texture.h       |  5 ++---
 libraries/gpu/src/gpu/Texture_ktx.cpp | 29 +++++----------------------
 2 files changed, 7 insertions(+), 27 deletions(-)

diff --git a/libraries/gpu/src/gpu/Texture.h b/libraries/gpu/src/gpu/Texture.h
index 1877b494cf..26de5a0804 100755
--- a/libraries/gpu/src/gpu/Texture.h
+++ b/libraries/gpu/src/gpu/Texture.h
@@ -324,9 +324,8 @@ public:
     protected:
         std::shared_ptr<storage::FileStorage> maybeOpenFile() const;
 
-        mutable std::mutex _cacheFileCreateMutex;
-        mutable std::mutex _cacheFileWriteMutex;
-        mutable std::weak_ptr<storage::FileStorage> _cacheFile;
+        mutable std::mutex _cacheFileMutex;
+        mutable std::shared_ptr<storage::FileStorage> _cacheFile;
 
         std::string _filename;
         cache::FilePointer _cacheEntry;
diff --git a/libraries/gpu/src/gpu/Texture_ktx.cpp b/libraries/gpu/src/gpu/Texture_ktx.cpp
index 08fc4ec101..49e18aaf78 100644
--- a/libraries/gpu/src/gpu/Texture_ktx.cpp
+++ b/libraries/gpu/src/gpu/Texture_ktx.cpp
@@ -188,35 +188,17 @@ KtxStorage::KtxStorage(const std::string& filename) : _filename(filename) {
 }
 
 std::shared_ptr<storage::FileStorage> KtxStorage::maybeOpenFile() const {
-    // 1. Try to get the shared ptr
-    // 2. If it doesn't exist, grab the mutex around its creation
-    // 3. If it was created before we got the mutex, return it
-    // 4. Otherwise, create it
-
-    std::shared_ptr<storage::FileStorage> file = _cacheFile.lock();
-    if (file) {
-        return file;
+    if (!_cacheFile) {
+        _cacheFile = std::make_shared<storage::FileStorage>(_filename.c_str());
     }
-
-    {
-        std::lock_guard<std::mutex> lock{ _cacheFileCreateMutex };
-
-        file = _cacheFile.lock();
-        if (file) {
-            return file;
-        }
-
-        file = std::make_shared<storage::FileStorage>(_filename.c_str());
-        _cacheFile = file;
-    }
-
-    return file;
+    return _cacheFile;
 }
 
 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) {
+        std::lock_guard<std::mutex> lock(_cacheFileMutex);
         auto file = maybeOpenFile();
         if (file) {
             auto storageView = file->createView(faceSize, faceOffset);
@@ -262,6 +244,7 @@ void KtxStorage::assignMipData(uint16 level, const storage::StoragePointer& stor
         return;
     }
 
+    std::lock_guard<std::mutex> lock(_cacheFileMutex);
     auto file = maybeOpenFile();
     if (!file) {
         qWarning() << "Failed to open file to assign mip data " << QString::fromStdString(_filename);
@@ -279,8 +262,6 @@ void KtxStorage::assignMipData(uint16 level, const storage::StoragePointer& stor
     imageData += ktx::IMAGE_SIZE_WIDTH;
 
     {
-        std::lock_guard<std::mutex> lock { _cacheFileWriteMutex };
-
         if (level != _minMipLevelAvailable - 1) {
             qWarning() << "Invalid level to be stored";
             return;