Add unicode general category lookup

Generate the lookup tables from UnicodeData.txt, do to that,
add gen_ugc, which uses csv, buffers, line, io and other modules
to do the job.

1 files changed, 52 insertions, 0 deletions

diff --git a/src/io.hh b/src/io.hh
new file mode 100644
index 0000000..315d0bb
--- /dev/null
+++ b/src/io.hh
@@ -0,0 +1,52 @@
+#ifndef IO_HH
+#define IO_HH
+
+#include <cstddef>
+#include <expected>
+#include <memory>
+#include <string>
+
+namespace io {
+
+enum class ReadError {
+  Error,
+  InvalidData,  // Used by decompress and such
+};
+
+enum class OpenError {
+  NoSuchFile,
+  NoAccess,
+  Error,
+};
+
+class Reader {
+ public:
+  virtual ~Reader() = default;
+
+  [[nodiscard]] virtual std::expected<size_t, ReadError> read(void* dst,
+                                                              size_t max) = 0;
+  [[nodiscard]] virtual std::expected<size_t, ReadError> skip(size_t max) = 0;
+
+  [[nodiscard]] std::expected<size_t, ReadError> read(std::string& str);
+
+  [[nodiscard]] std::expected<size_t, ReadError> repeat_read(void* dst,
+                                                             size_t max);
+  [[nodiscard]] std::expected<size_t, ReadError> repeat_read(std::string& str);
+  [[nodiscard]] std::expected<size_t, ReadError> repeat_skip(size_t max);
+
+ protected:
+  Reader() = default;
+
+  Reader(Reader const&) = delete;
+  Reader& operator=(Reader const&) = delete;
+};
+
+[[nodiscard]] std::expected<std::unique_ptr<Reader>, OpenError> open(
+    const std::string& file_path);
+[[nodiscard]] std::expected<std::unique_ptr<Reader>, OpenError> openat(
+    int dirfd, const std::string& file_path);
+[[nodiscard]] std::unique_ptr<Reader> memory(std::string data);
+
+}  // namespace io
+
+#endif  // IO_HH