Added a basic config file, config class, and some stubs

for object storage functionality.

src/Config.cpp

@@ -0,0 +1,70 @@
+
+#include "Config.h"
+#include <boost/thread/mutex.hpp>
+#include <boost/property_tree/ini_parser.hpp>
+#include <boost/filesystem.hpp>
+
+#include <stdlib.h>
+#include <vector>
+
+using namespace std;
+
+namespace
+{
+    boost::mutex m;
+    storagemanager::Config *inst = NULL;
+}
+    
+namespace storagemanager
+{
+
+Config * Config::get()
+{
+    if (inst)
+        return inst;
+    boost::mutex::scoped_lock s(m);
+    if (inst)
+        return inst;
+    inst = new Config();
+    return inst;
+}
+
+Config::Config()
+{
+    /* This will search the current directory,
+       then the $COLUMNSTORE_INSTALL_DIR/etc,
+       then /etc
+       looking for storagemanager.cnf
+       
+       We can change this however we need later.
+    */
+    char *cs_install_dir = getenv("COLUMNSTORE_INSTALL_DIR");
+    
+    vector<string> paths;
+    
+    // the paths to search in order
+    paths.push_back("./");
+    if (cs_install_dir)
+        paths.push_back(cs_install_dir);
+    paths.push_back("/etc");
+    
+    for (int i = 0; i < paths.size(); i++)
+    {
+        if (boost::filesystem::exists(paths[i] + "/storagemanager.cnf"))
+        {
+            filename = paths[i] + "/storagemanager.cnf";
+            break;
+        }
+    }
+    if (filename.empty())
+        throw runtime_error("Config: Could not find the config file for StorageManager");
+        
+    boost::property_tree::ini_parser::read_ini(filename, contents);
+}
+
+string Config::getValue(const string &section, const string &key) const
+{
+    return contents.get<string>(section + "." + key);
+}
+
+}