bytestream.h

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/* SPDX-License-Identifier: MIT */
#ifndef AJA_BYTESTREAM_H
#define AJA_BYTESTREAM_H
 
#include <stddef.h>
#include <string.h>
#include "ajabase/common/types.h"
 
class AJAByteStream {
    public:
        AJAByteStream(void *buf = NULL, size_t pos = 0);
 
        size_t Pos() const;
        void *Buffer() const;
        
        void Reset();
        void Seek(size_t val);      // Seeks to an absolute position
        void SeekFwd(size_t val);   // Seeks forward n bytes
        void SeekRev(size_t val);   // Seeks backwards n bytes
 
        void Set(uint8_t val, size_t bytes);
        void Write(const void *buf, size_t bytes);
        void Write8(uint8_t val);
        void Write16LE(uint16_t val);
        void Write16BE(uint16_t val);
        void Write32LE(uint32_t val);
        void Write32BE(uint32_t val);
        void Write64LE(uint64_t val);
        void Write64BE(uint64_t val);
 
        void Read(void *buf, size_t LEn);
        uint8_t Read8();
        uint16_t Read16LE();
        uint16_t Read16BE();
        uint32_t Read32LE();
        uint32_t Read32BE();
        uint64_t Read64LE();
        uint64_t Read64BE();
 
    private:
        uint8_t     *b; // Beginning buffer position
        uint8_t     *c; // Current buffer position
};
 
inline AJAByteStream::AJAByteStream(void *buf, size_t pos) : b((uint8_t *)buf) {
    Seek(pos);
}
 
inline size_t AJAByteStream::Pos() const {
    return (size_t)(c - b);
}
 
inline void *AJAByteStream::Buffer() const {
    return b;
}
 
inline void AJAByteStream::Reset() {
    c = b;
    return;
}
 
inline void AJAByteStream::Seek(size_t val) {
    c = b + val;
    return;
}
 
inline void AJAByteStream::SeekFwd(size_t val) {
    c += val;
    return;
}
 
inline void AJAByteStream::SeekRev(size_t val) {
    c -= val;
    return;
}
 
inline void AJAByteStream::Set(uint8_t val, size_t bytes) {
    uint8_t *last = c + bytes;
    while(c != last) *c++ = val;
    return;
}
 
inline void AJAByteStream::Write(const void *buf, size_t bytes) {
    memcpy(c, buf, bytes);
    c += bytes;
    return;
}
 
inline void AJAByteStream::Write8(uint8_t val) {
    *c++ = val;
    return;
}
 
inline void AJAByteStream::Write16LE(uint16_t val) {
    c[0] = val & 0xFF;
    c[1] = (val >> 8) & 0xFF;
    c += 2;
    return;
}
 
inline void AJAByteStream::Write16BE(uint16_t val) {
    c[0] = (val >> 8) & 0xFF;
    c[1] = val & 0xFF;
    c += 2;
    return;
}
 
inline void AJAByteStream::Write32LE(uint32_t val) {
    c[0] = val & 0xFF;
    c[1] = (val >> 8) & 0xFF;
    c[2] = (val >> 16) & 0xFF;
    c[3] = (val >> 24) & 0xFF;
    c += 4;
    return;
}
 
inline void AJAByteStream::Write32BE(uint32_t val) {
    c[0] = (val >> 24) & 0xFF;
    c[1] = (val >> 16) & 0xFF;
    c[2] = (val >> 8) & 0xFF;
    c[3] = val & 0xFF;
    c += 4;
    return;
}
 
inline void AJAByteStream::Write64LE(uint64_t val) {
    c[0] = val & 0xFF;
    c[1] = (val >> 8) & 0xFF;
    c[2] = (val >> 16) & 0xFF;
    c[3] = (val >> 24) & 0xFF;
    c[4] = (val >> 32) & 0xFF;
    c[5] = (val >> 40) & 0xFF;
    c[6] = (val >> 48) & 0xFF;
    c[7] = (val >> 56) & 0xFF;
    c += 8;
    return;
}
 
inline void AJAByteStream::Write64BE(uint64_t val) {
    c[0] = (val >> 56) & 0xFF;
    c[1] = (val >> 48) & 0xFF;
    c[2] = (val >> 40) & 0xFF;
    c[3] = (val >> 32) & 0xFF;
    c[4] = (val >> 24) & 0xFF;
    c[5] = (val >> 16) & 0xFF;
    c[6] = (val >> 8) & 0xFF;
    c[7] = val & 0xFF;
    c += 8;
    return;
}
 
inline void AJAByteStream::Read(void *buf, size_t bytes) {
    uint8_t *last = c + bytes, *o = (uint8_t *)buf;
    while(c != last) *o++ = *c++;
    return;
}
 
inline uint8_t AJAByteStream::Read8() {
    return *c++;
}
 
inline uint16_t AJAByteStream::Read16LE() {
    uint16_t ret;
    ret = (uint16_t)c[0];
    ret |= (uint16_t)c[1] << 8;
    c += 2;
    return ret;
}
 
inline uint16_t AJAByteStream::Read16BE() {
    uint16_t ret;
    ret = (uint16_t)c[0] << 8;
    ret |= (uint16_t)c[1];
    c += 2;
    return ret;
}
 
inline uint32_t AJAByteStream::Read32LE() {
    uint32_t ret;
    ret = (uint32_t)c[0];
    ret |= (uint32_t)c[1] << 8;
    ret |= (uint32_t)c[2] << 16;
    ret |= (uint32_t)c[3] << 24;
    c += 4;
    return ret;
}
 
inline uint32_t AJAByteStream::Read32BE() {
    uint32_t ret;
    ret = (uint32_t)c[0] << 24;
    ret |= (uint32_t)c[1] << 16;
    ret |= (uint32_t)c[2] << 8;
    ret |= (uint32_t)c[3];
    c += 4;
    return ret;
}
 
inline uint64_t AJAByteStream::Read64LE() {
    uint64_t ret;
    ret = (uint64_t)c[0];
    ret |= (uint64_t)c[1] << 8;
    ret |= (uint64_t)c[2] << 16;
    ret |= (uint64_t)c[3] << 24;
    ret |= (uint64_t)c[4] << 32;
    ret |= (uint64_t)c[5] << 40;
    ret |= (uint64_t)c[6] << 48;
    ret |= (uint64_t)c[7] << 56;
    c += 8;
    return ret;
}
 
inline uint64_t AJAByteStream::Read64BE() {
    uint64_t ret;
    ret = (uint64_t)c[0] << 56;
    ret |= (uint64_t)c[1] << 48;
    ret |= (uint64_t)c[2] << 40;
    ret |= (uint64_t)c[3] << 32;
    ret |= (uint64_t)c[4] << 24;
    ret |= (uint64_t)c[5] << 16;
    ret |= (uint64_t)c[6] << 8;
    ret |= (uint64_t)c[7];
    c += 8;
    return ret;
}
 
#endif /* ifndef AJA_BYTESTREAM_H */