Fix thumbnail cache retrieval

Use direct reading of thumbnail-cache files, instead of using libCurl

simgear/io/iostreams/sgstream.cxx

@@ -227,6 +227,20 @@ void sg_ifstream::open( const SGPath& name, ios_openmode io_mode )
     std::ifstream::open(ps.c_str(), io_mode);
 }
 
+std::string sg_ifstream::read_all()
+{
+	this->seekg(0, std::ios::end); // seek to end
+	const auto pos = this->tellg();
+
+	std::string result;
+	result.resize(pos);
+
+	this->seekg(0, std::ios::beg);
+	this->read(const_cast<char*>(result.data()), pos);
+    return result;
+}
+
+
 sg_ofstream::sg_ofstream(const SGPath& path, ios_openmode io_mode)
 {
 #if defined(SG_WINDOWS)

simgear/io/iostreams/sgstream.hxx

@@ -196,6 +196,10 @@ public:
 
     void open( const SGPath& name,
 	       ios_openmode io_mode = ios_in|ios_binary );
+    
+    /// read the entire stream into a buffer. Use on files, etc - not recommended on streams
+    /// which never EOF, will bvlock forever.
+    std::string read_all();
 };
 
 class sg_ofstream : public std::ofstream

simgear/package/Root.cxx

@@ -178,8 +178,7 @@ public:
                 SG_LOG(SG_IO, SG_WARN, "Download failed for: " << u << ", will use old cached data");
                 cachePath.touch(); // touch the file so we don't repeat this danxce
                 // kick a load from the cache
-                
-                queueLoadFromPersistentCache(u, cachePath);
+                loadFromPersistentCache(u, cachePath);
             }
         }
 
@@ -202,6 +201,7 @@ public:
 
         std::string u = pendingThumbnails.front();
         pendingThumbnails.pop_front();
+        
         thumbnailDownloadRequest = new Root::ThumbnailDownloader(this, u);
 
         if (http) {
@@ -260,11 +260,11 @@ public:
             return false;
         }
         
-        queueLoadFromPersistentCache(url, cachePath);
+        loadFromPersistentCache(url, cachePath);
         return true;
     }
     
-    void queueLoadFromPersistentCache(const std::string& url, const SGPath& path)
+    void loadFromPersistentCache(const std::string& url, const SGPath& path)
     {
         assert(path.exists());
         
@@ -277,17 +277,9 @@ public:
             assert(it->second.pathOnDisk.isNull() || (it->second.pathOnDisk == path));
         }
         
-        if (it->second.requestPending) {
-            return; // all done
-        }
-        
-        it->second.requestPending = true;
-        auto dl = new Root::ThumbnailDownloader(this, path.fileUrl(), url);
-        if (http) {
-            http->makeRequest(dl);
-        } else {
-            httpPendingRequests.push_back(dl);
-        }
+        sg_ifstream thumbnailStream(path, std::ios::in | std::ios::binary);
+        string bytes = thumbnailStream.read_all();
+        fireDataForThumbnail(url, reinterpret_cast<const uint8_t*>(bytes.data()), bytes.size());
     }
     
     DelegateVec delegates;
@@ -813,7 +805,7 @@ void Root::requestThumbnailData(const std::string& aUrl)
         }
     } else {
         if (!it->second.requestPending && it->second.pathOnDisk.exists()) {
-            d->queueLoadFromPersistentCache(aUrl, it->second.pathOnDisk);
+            d->loadFromPersistentCache(aUrl, it->second.pathOnDisk);
         }
     }
 }

simgear/scene/material/Effect.cxx

@@ -107,14 +107,7 @@ bool loadShaderFromUTF8File(osg::Shader* shader, const std::string& fileName)
     if (!inStream.is_open())
         return false;
     
-    string shaderSource;
-    while (!inStream.eof()) {
-        char bytes[8192];
-        inStream.read(bytes, 8192);
-        shaderSource.append(bytes, inStream.gcount());
-    }
-    inStream.close();
-    shader->setShaderSource(shaderSource);
+    shader->setShaderSource(inStream.read_all());
     return true;
 }