Add check for absolute path of config file

src/utils/configfile.cc

@@ -43,6 +43,7 @@ const OptionId kConfigFileId{
     "parameter per line, e.g.:\n--weights=/path/to/weights",
     'c'};
 const char* kDefaultConfigFile = "lc0.config";
+const char* kDefaultConfigFileParam = "<default>";
 }  // namespace
 
 std::vector<std::string> ConfigFile::arguments_;
@@ -55,7 +56,7 @@ void ConfigFile::PopulateOptions(OptionsParser* options) {
 // ProcessAllFlags() that should be called only once, and needs the config file.
 std::string ConfigFile::ProcessConfigFlag(
     const std::vector<std::string>& args) {
-  std::string filename = kDefaultConfigFile;
+  std::string filename = kDefaultConfigFileParam;
   for (auto iter = args.begin(), end = args.end(); iter != end; ++iter) {
     std::string param = *iter;
 
@@ -81,28 +82,33 @@ std::string ConfigFile::ProcessConfigFlag(
 bool ConfigFile::Init(OptionsParser* options) {
   arguments_.clear();
 
-  // Get the relative path from the config file parameter.
+  // Get the path from the config file parameter.
   std::string filename = ProcessConfigFlag(CommandLine::Arguments());
 
-  // If filename is an empty string then return true.  This is to override
+  // If filename is an empty string then return true. This is to override
   // loading the default configuration file.
   if (filename == "") return true;
 
-  filename = CommandLine::BinaryDirectory() + "/" + filename;
-
   // Parses the file into the arguments_ vector.
   if (!ParseFile(filename, options)) return false;
 
   return true;
 }
 
-bool ConfigFile::ParseFile(const std::string& filename,
+bool ConfigFile::ParseFile(std::string& filename,
                            OptionsParser* options) {
-  std::ifstream input(filename);
 
   // Check to see if we are using the default config file or not.
-  OptionsDict dict = options->GetOptionsDict();
-  const bool using_default_config = dict.IsDefault<std::string>(kConfigFileId);
+  const bool using_default_config = 
+      filename == std::string(kDefaultConfigFileParam);
+
+  // If no logfile was set on the command line, then the default is
+  // to check in the binary directory.
+  if (using_default_config) {
+    filename = CommandLine::BinaryDirectory() + '/' + kDefaultConfigFile;
+  }
+
+  std::ifstream input(filename);
 
   if (!input.is_open()) {
     // It is okay if we cannot open the default file since it is normal

src/utils/configfile.h

@@ -49,8 +49,9 @@ class ConfigFile {
 
  private:
   // Parses the config file into the arguments_ vector.
-  static bool ParseFile(const std::string& filename, OptionsParser* options);
+  static bool ParseFile(std::string& filename, OptionsParser* options);
 
+  // Returns the absolute path to the config file argument given.
   static std::string ProcessConfigFlag(const std::vector<std::string>& args);
 
   static std::vector<std::string> arguments_;