data: indexer processes

* TaskBuildIndex starts seperate indexer processes and communicates via shared memory
* indexer processes get restarted if they fail
* indexer processes are killed when the app closes or crashes
* added utility class SharedMemory to allocate and access shared memory, providing basic data structures
* added SharedMemoryGarbageCollector for keeping track of running instances and cleaning up shared memory in case of a crash
* show errors for source files that crashed during indexing
* added basic exception handling to task scheduling
* added option to turn off processes and use threads in preferences, but still use shared memory

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src/lib_java/data/indexer/IndexerCommandJava.cpp

@@ -25,6 +25,18 @@ std::string IndexerCommandJava::getKindString() const
 	return getIndexerKindString();
 }
 
+size_t IndexerCommandJava::getByteSize() const
+{
+	size_t size = IndexerCommand::getByteSize() + sizeof(*this);
+
+	for (auto i : m_classPath)
+	{
+		size += i.str().size();
+	}
+
+	return size;
+}
+
 std::vector<FilePath> IndexerCommandJava::getClassPath() const
 {
 	return m_classPath;

src/lib_java/data/indexer/IndexerCommandJava.h

@@ -20,7 +20,8 @@ public:
 		const std::vector<FilePath>& classPath);
 	virtual ~IndexerCommandJava();
 
-	std::string getKindString() const override;
+	virtual std::string getKindString() const override;
+	virtual size_t getByteSize() const override;
 
 	std::vector<FilePath> getClassPath() const;