1 files changed, 52 insertions, 0 deletions
diff --git a/src/logger_file.cc b/src/logger_file.cc
new file mode 100644
index 0000000..ad11398
--- /dev/null
+++ b/src/logger_file.cc
@@ -0,0 +1,52 @@
+#include "common.hh"
+
+#include "logger_base.hh"
+
+#include <fstream>
+#include <mutex>
+
+namespace {
+
+class LoggerFile : public LoggerBase {
+public:
+  explicit LoggerFile(std::filesystem::path const& path)
+    : out_(path, std::ios::out | std::ios::app) {}
+
+  bool good() const {
+    return out_.good();
+  }
+
+protected:
+  void msg(Level lvl, std::string_view msg) override {
+    std::lock_guard<std::mutex> lock(mutex_);
+    switch (lvl) {
+    case Level::ERR:
+      out_ << "Error: " << msg << std::endl;
+      break;
+    case Level::WARN:
+      out_ << "Warning: " << msg << std::endl;
+      break;
+    case Level::INFO:
+      out_ << msg << std::endl;
+      break;
+    case Level::DBG:
+      out_ << "Debug: " << msg << std::endl;
+      break;
+    }
+  }
+
+private:
+  std::mutex mutex_;
+  std::fstream out_;
+};
+
+}  // namespace
+
+std::unique_ptr<Logger> Logger::create_file(std::filesystem::path const& path,
+                                            Logger* fallback) {
+  auto logger = std::make_unique<LoggerFile>(path);
+  if (logger->good())
+    return logger;
+  fallback->warn("Unable to open %s for appending.", path.c_str());
+  return nullptr;
+}