Rewrite config file parser

I noticed it didn't work correctly in some cases...

include/util.h

@@ -10,7 +10,7 @@ inline std::string read_setting_default(const std::string &name, std::istream &i
 {
 	try {
 		return read_setting(name, is);
-	} catch(std::runtime_error &e) {
+	} catch(const std::runtime_error &e) {
 		return def;
 	}
 }

util.cpp

@@ -3,61 +3,43 @@
 
 #include "util.h"
 
-inline std::string trim(const std::string &s)
+static inline std::string trim(const std::string &s)
 {
-  size_t front = 0;
-  while(s[front] == ' '    ||
-        s[front] == '\t'   ||
-        s[front] == '\r'   ||
-        s[front] == '\n'
-       )
-    ++front;
+	auto isspace = [] (char c) -> bool { return c == ' ' || c == '\t' || c == '\r' || c == '\n'; };
 
-  size_t back = s.size();
-  while(back > front &&
-        (s[back-1] == ' '  ||
-         s[back-1] == '\t' ||
-         s[back-1] == '\r' ||
-         s[back-1] == '\n'
-        )
-       )
-    --back;
+	size_t front = 0;
+	while(isspace(s[front]))
+		++front;
+	size_t back = s.size() - 1;
+	while(back > front && isspace(s[back]))
+		--back;
 
-  return s.substr(front, back - front);
+	return s.substr(front, back - front + 1);
 }
 
-#define EOFCHECK() do { \
-    if (is.eof()) { \
-      std::ostringstream oss; \
-      oss << "Setting '" << name << "' not found."; \
-      throw std::runtime_error(oss.str()); \
-    } \
-  } while(0)
-
 std::string read_setting(const std::string &name, std::istream &is)
 {
-  char c;
-  char s[256];
-  std::string nm, value;
+	char linebuf[512];
+	while (is.good()) {
+		is.getline(linebuf, sizeof(linebuf));
 
-  next:
-  while((c = is.get()) == ' ' || c == '\t' || c == '\r' || c == '\n')
-    ;
-  EOFCHECK();
-  if(c == '#') // Ignore comments
-    is.ignore(0xffff, '\n');
-  EOFCHECK();
-  s[0] = c; // The current char belongs to the name too
-  is.get(&s[1], 255, '=');
-  is.ignore(1); // Jump over the =
-  EOFCHECK();
-  nm = trim(std::string(s));
-  is.get(s, 256, '\n');
-  value = trim(std::string(s));
-  if(name == nm)
-    return value;
-  else
-    goto next;
+		for(char *p = linebuf; *p; p++) {
+			if(*p != '#')
+				continue;
+			*p = '\0'; // Cut off at the first #
+			break;
+		}
+		std::string line(linebuf);
+
+		auto pos = line.find('=');
+		if (pos == std::string::npos)
+			continue;
+		auto key = trim(line.substr(0, pos));
+		if (key != name)
+			continue;
+		return trim(line.substr(pos+1));
+	}
+	std::ostringstream oss;
+	oss << "Setting '" << name << "' not found";
+	throw std::runtime_error(oss.str());
 }
-
-#undef EOFCHECK