Created a new branch to act as a submodule of common classes

utilities/config_utility.cpp

@@ -0,0 +1,188 @@
+/* Copyright: (c) Kayne Ruse 2013-2015
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#include "config_utility.hpp"
+
+#include <cstdlib>
+#include <cstring>
+#include <fstream>
+#include <sstream>
+#include <stdexcept>
+
+void ConfigUtility::Load(std::string fname, bool skipMissingFile, int argc, char* argv[]) {
+	//clear the stored configuration
+	configMap.clear();
+
+	//use the default file
+	if (argc < 2) {
+		configMap = Read(fname, skipMissingFile);
+		return;
+	}
+
+	//some variables to use
+	table_t redirectedFile;
+	table_t cmdLineParams;
+	char key[256], val[256];
+	bool redirectUsed = false;
+
+	//reading from the command line
+	for (int i = 1; i < argc; ++i) {
+		//read from a specified config file
+		if (!strncmp(argv[i], "-config=", 8)) {
+			//older specified files take precedence
+			table_t tmp = Read(argv[i] + 8, skipMissingFile);
+			redirectedFile.insert(tmp.begin(), tmp.end());
+			redirectUsed = true;
+			continue;
+		}
+
+		//set some specific values
+		if (!strncmp(argv[i], "-", 1)) {
+			//wipe the variables
+			memset(key, 0, 256);
+			memset(key, 0, 256);
+
+			//read the key-value pair
+			if (sscanf(argv[i], "-%[^=]=%[^\\0]", key, val) != 2) {
+				std::ostringstream os;
+				os << "Failed to read a command line config argument (expected -%s=%s):" << std::endl;
+				os << "\targv[" << i << "]: " << argv[i] << std::endl;
+				os << "\tkey: " << key << std::endl;
+				os << "\tval: " << val << std::endl;
+				throw(std::runtime_error( os.str() ));
+			}
+			cmdLineParams[key] = val;
+		}
+	}
+
+	//finally, construct the final config table
+	if (!redirectUsed) {
+		redirectedFile = Read(fname, skipMissingFile);
+	}
+	configMap.insert(cmdLineParams.begin(), cmdLineParams.end());
+	configMap.insert(redirectedFile.begin(), redirectedFile.end());
+}
+
+ConfigUtility::table_t ConfigUtility::Read(std::string fname, bool skipMissingFile) {
+	//read in and return this file's data
+	table_t retTable;
+	std::ifstream is(fname);
+
+	if (!is.is_open()) {
+		if (skipMissingFile) {
+			return {}; //empty table
+		}
+		std::ostringstream os;
+		os << "Failed to open a config file: " << fname;
+		throw(std::runtime_error( os.str() ));
+	}
+
+	std::string key, val;
+
+	while(true) { //forever
+		//eat whitespace
+		while(isspace(is.peek())) {
+			is.ignore();
+		}
+
+		//end of file
+		if (is.eof()) {
+			break;
+		}
+
+		//skip comment lines
+		if (is.peek() == '#') {
+			while(is.peek() != '\n' && !is.eof()) {
+				is.ignore();
+			}
+			continue;
+		}
+
+		//read in the pair
+		getline(is, key,'=');
+		getline(is, val);
+
+		//eat the whitespace at the start & end
+		while(key.size() && isspace( *key.begin() )) {
+			key.erase(0, 1);
+		}
+		while(val.size() && isspace( *val.begin() )) {
+			val.erase(0, 1);
+		}
+
+		while(key.size() && isspace( *(key.end()-1) )) {
+			key.erase(key.end() - 1);
+		}
+		while(val.size() && isspace( *(val.end()-1) )) {
+			val.erase(val.end() - 1);
+		}
+
+		//disallow empty/wiped pairs
+		if (key.size() == 0 || val.size() == 0) {
+			continue;
+		}
+
+		//save the pair
+		retTable[key] = val;
+	}
+
+	is.close();
+
+	//load in any subordinate config files
+	if (retTable.find("config.next") != retTable.end()) {
+		table_t subTable = Read(retTable["config.next"], skipMissingFile);
+		retTable.insert(subTable.begin(), subTable.end());
+	}
+
+	return retTable;
+}
+
+//-------------------------
+//Convert to a type
+//-------------------------
+
+std::string& ConfigUtility::String(std::string s) {
+	return configMap[s];
+}
+
+int ConfigUtility::Integer(std::string s) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
+		return 0;
+	}
+	return atoi(it->second.c_str());
+}
+
+double ConfigUtility::Double(std::string s) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
+		return 0.0;
+	}
+	return atof(it->second.c_str());
+}
+
+bool ConfigUtility::Boolean(std::string s) {
+	table_t::iterator it = configMap.find(s);
+	if (it == configMap.end()) {
+		return false;
+	}
+	return it->second == "true";
+}