RawFileReader.hpp

Go to the documentation of this file.

#ifndef BYTEME_RAW_FILE_READER_HPP
#define BYTEME_RAW_FILE_READER_HPP
 
#include <vector>
#include <stdexcept>
#include <cstdio>
#include <cstddef>
#include <optional>
 
#include "Reader.hpp"
#include "SelfClosingFILE.hpp"
#include "check_buffer_size.hpp"
 
namespace byteme {
 
struct RawFileReaderOptions {
    std::size_t buffer_size = 65536;
 
    std::optional<unsigned> bufsiz;
};
 
class RawFileReader final : public Reader {
public:
    RawFileReader(const char* path, const RawFileReaderOptions& options) :
        my_file(path, "rb"),
        my_buffer(check_buffer_size(options.buffer_size))
    {
        set_optional_bufsiz(my_file, options.bufsiz);
    }
 
public:
    bool load() {
        if (!my_okay) {
            return false;
        }
 
        auto& handle = my_file.handle;
        my_read = std::fread(my_buffer.data(), sizeof(unsigned char), my_buffer.size(), handle);
 
        if (my_read < my_buffer.size()) {
            if (std::feof(handle)) {
                my_okay = false;
            } else {
                throw std::runtime_error("failed to read raw binary file (fread error " + std::to_string(std::ferror(handle)) + ")");
            }
        }
 
        return true;
    }
 
    const unsigned char* buffer() const {
        return my_buffer.data();
    }
 
    std::size_t available() const {
        return my_read;
    }
 
private:
    SelfClosingFILE my_file;
    std::vector<unsigned char> my_buffer;
    std::size_t my_read = 0;
    bool my_okay = true;
};
 
}
 
#endif