45 lines
978 B
C++
45 lines
978 B
C++
#include <bit>
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#include <climits>
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#include <cmath>
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#include <cstdio>
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class BinaryEncoder {
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private:
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unsigned char *const buffer;
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std::size_t index;
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public:
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BinaryEncoder(unsigned char *b) noexcept : buffer(b) {}
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void write(unsigned char val, unsigned char width = 0)
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{
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if (width == 0)
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width = std::bit_width(val);
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const unsigned char bitindex = index % CHAR_BIT;
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const std::size_t byteindex = index / CHAR_BIT;
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buffer[byteindex] &= compl(UCHAR_MAX << bitindex);
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buffer[byteindex] |= val << bitindex;
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const unsigned char bitsWritten = CHAR_BIT - bitindex;
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if (width <= bitsWritten) {
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index += width;
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} else {
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index += bitsWritten;
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this->write(val >> bitsWritten);
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}
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}
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};
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int main() {
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unsigned char buf[1];
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BinaryEncoder be(buf);
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be.write(0b111u);
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be.write(0b100u);
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if (buf[0] == 39) std::puts("miku");
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} |