added logging module and a sandbox project

source/core/logger/file_sink.cpp

@@ -0,0 +1,68 @@
+#include "matador/logger/file_sink.hpp"
+
+#include "matador/utils/os.hpp"
+#include "matador/utils/string.hpp"
+
+#include <vector>
+
+namespace matador::logger {
+
+file_sink::file_sink(const std::string &path)
+: path_(path)
+{
+  std::string filename(path);
+  // find last dir delimiter
+  const char *last = strrchr(path.c_str(), os::DIR_SEPARATOR);
+  if (last != nullptr) {
+    path_.assign(path.data(), last-path.data());
+  } else {
+    path_.clear();
+  }
+
+  if (last != nullptr) {
+    filename = (last + 1);
+  }
+  // extract base path and extension
+  if (std::vector<std::string> result; utils::split(filename, '.', result) != 2) {
+    throw std::logic_error("split path must consists of two elements");
+  }
+  // get the current path
+  const auto pwd = os::get_current_dir();
+  // make the path
+  os::mkpath(path_);
+  // change into the path
+  os::chdir(path_);
+  // create the file
+  stream = os::fopen(filename, "a");
+  if (stream == nullptr) {
+    os::chdir(pwd);
+    throw std::logic_error("error opening file");
+  }
+  os::chdir(pwd);
+}
+
+file_sink::file_sink(const char *path)
+  : file_sink(std::string(path))
+{}
+
+file_sink::~file_sink()
+{
+  if (stream) {
+    fclose(stream);
+    stream = nullptr;
+  }
+}
+
+std::string file_sink::path() const
+{
+  return path_;
+}
+
+stdout_sink::stdout_sink()
+  : basic_file_sink(stdout)
+{}
+
+stderr_sink::stderr_sink()
+  : basic_file_sink(stderr)
+{}
+}