method to enforce float

ConfigFileParser.cpp

@@ -2,6 +2,8 @@
 // info@patrickbrosi.de
 
 #include <algorithm>
+#include <cmath>
+#include <cstdlib>
 #include <fstream>
 #include <iostream>
 #include <limits>
@@ -230,14 +232,37 @@ void ConfigFileParser::parse(std::istream& is, const std::string& path) {
 const std::string& ConfigFileParser::getStr(Sec sec, const Key& key) const {
   return _kvs[_secs.find(sec)->second].find(key)->second.val;
 }
+
 // _____________________________________________________________________________
 int ConfigFileParser::getInt(Sec sec, const Key& key) const {
   return atoi(_kvs[_secs.find(sec)->second].find(key)->second.val.c_str());
 }
+
 // _____________________________________________________________________________
 double ConfigFileParser::getDouble(Sec sec, const Key& key) const {
+  auto v = _kvs[_secs.find(sec)->second].find(key)->second;
+  if (!isFloat(v.val)) {
+    throw ParseExc(v.line, v.pos, "floating number for '" + key + "'",
+                   std::string("'") + v.val + "'", v.file);
+  }
   return atof(_kvs[_secs.find(sec)->second].find(key)->second.val.c_str());
 }
+
+// _____________________________________________________________________________
+double ConfigFileParser::getPosDouble(Sec sec, const Key& key) const {
+  auto v = _kvs[_secs.find(sec)->second].find(key)->second;
+  if (!isFloat(v.val)) {
+    throw ParseExc(v.line, v.pos, "positive floating number for '" + key + "'",
+                   std::string("'") + v.val + "'", v.file);
+  }
+  double d = atof(_kvs[_secs.find(sec)->second].find(key)->second.val.c_str());
+  if (d < 0) {
+    throw ParseExc(v.line, v.pos, "positive floating number for '" + key + "'",
+                   std::string("'") + v.val + "'", v.file);
+  }
+  return d;
+}
+
 // _____________________________________________________________________________
 bool ConfigFileParser::getBool(Sec sec, const Key& key) const {
   return toBool(getStr(sec, key));
@@ -368,6 +393,13 @@ void ConfigFileParser::updateVals(size_t sec, const KeyVals& kvs) {
 }
 
 // _____________________________________________________________________________
+bool ConfigFileParser::isFloat(const std::string& str) const {
+  char* l = 0;
+  auto v = std::strtod(str.c_str(), &l);
+  return l != str.c_str() && *l == 0 && v != HUGE_VAL;
+}
+
+// _____________________________________________________________________________
 std::string ConfigFileParser::relPath(const std::string& file,
                                       std::string curF) const {
   // pass absolute paths through unchanged

ConfigFileParser.h

@@ -78,6 +78,7 @@ class ConfigFileParser {
   const std::string& getStr(Sec sec, const Key& key) const;
   int getInt(Sec sec, const Key& key) const;
   double getDouble(Sec sec, const Key& key) const;
+  double getPosDouble(Sec sec, const Key& key) const;
   bool getBool(Sec sec, const Key& key) const;
 
   std::vector<std::string> getStrArr(Sec sec, const Key& key, char del) const;
@@ -102,6 +103,8 @@ class ConfigFileParser {
   std::string trim(const std::string& str) const;
   bool toBool(std::string str) const;
 
+  bool isFloat(const std::string& str) const;
+
   void updateVals(size_t sec, const KeyVals& kvs);
   std::string relPath(const std::string& file, std::string curFile) const;
 };