- Enable NAG parsing

- Add the LargeFileStream interface to handle large file
- Debug parsing

1 files changed, 52 insertions, 0 deletions

diff --git a/src/LargeFileStream.hpp b/src/LargeFileStream.hpp
new file mode 100644
index 0000000..6ac87e8
--- /dev/null
+++ b/src/LargeFileStream.hpp
@@ -0,0 +1,52 @@
+#define BUFFER_SIZE (1024 * 1024 / 2)
+
+#include <fstream>
+#include <iostream>
+#include <string>
+
+namespace pgnp {
+using namespace std;
+
+class LargeFileStream {
+  /// @brief File to load
+  ifstream file;
+  /// @brief In memory buffer
+  char buffer[BUFFER_SIZE];
+  /// @brief Number of chuck read minus 1
+  long chuck_count;
+  /// @brief Number of byte read during the last file access
+  long last_read_size;
+  /// @brief Keep track of the file offset (to prevent backward read)
+  long last_loc;
+  /// @brief Use a string as file content
+  std::string content;
+  /// @brief Use to shortcut some methods
+  bool use_string;
+  /// @brief End Of File ?
+  bool eof;
+
+  /// @brief Load the next chuck of data from disk to memory
+  void ReadNextChunk();
+
+public:
+  LargeFileStream();
+  void FromFile(std::string filepath);
+  /// @brief Emulate file access with a string
+  void FromString(std::string content);
+  /// @brief Allow array like access to the file
+  char operator[](long loc);
+  /// @brief Check if we reach the EOF
+  bool IsEOF(long loc);
+
+  // Various Exceptions
+  struct BackwardRead : public std::exception {
+    const char *what() const throw() {
+      return "LargeFileStream cannot read backward";
+    }
+  };
+  struct ReadToFar : public std::exception {
+    const char *what() const throw() { return "You reach the end of the file"; }
+  };
+};
+
+} // namespace pgnp
\ No newline at end of file