#pragma once #include <stdio.h> #include <memory> #include "../files.hpp" class stream { public: virtual int read(void *buf, size_t len); virtual int write(const void *buf, size_t len); virtual off_t seek(off_t off, int whence); virtual ~stream() = default; }; using stream_ptr = std::unique_ptr<stream>; // Delegates all operations to base stream class filter_stream : public stream { public: filter_stream(stream_ptr &&base) : base(std::move(base)) {} int read(void *buf, size_t len) override; int write(const void *buf, size_t len) override; protected: stream_ptr base; }; // Byte stream that dynamically allocates memory class byte_stream : public stream { public: byte_stream(uint8_t *&buf, size_t &len); template <class byte> byte_stream(byte *&buf, size_t &len) : byte_stream(reinterpret_cast<uint8_t *&>(buf), len) {} int read(void *buf, size_t len) override; int write(const void *buf, size_t len) override; off_t seek(off_t off, int whence) override; private: uint8_t *&_buf; size_t &_len; size_t _pos = 0; size_t _cap = 0; void resize(size_t new_pos, bool zero = false); }; // File stream but does not close the file descriptor at any time class fd_stream : public stream { public: fd_stream(int fd) : fd(fd) {} int read(void *buf, size_t len) override; int write(const void *buf, size_t len) override; off_t seek(off_t off, int whence) override; private: int fd; }; /* **************************************** * Bridge between stream class and C stdio * ****************************************/ // sFILE -> stream_ptr class fp_stream final : public stream { public: fp_stream(FILE *fp = nullptr) : fp(fp, fclose) {} fp_stream(sFILE &&fp) : fp(std::move(fp)) {} int read(void *buf, size_t len) override; int write(const void *buf, size_t len) override; off_t seek(off_t off, int whence) override; private: sFILE fp; }; // stream_ptr -> sFILE sFILE make_stream_fp(stream_ptr &&strm); template <class T, class... Args> sFILE make_stream_fp(Args &&... args) { return make_stream_fp(stream_ptr(new T(std::forward<Args>(args)...))); }