git

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#include "git-compat-util.h"
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#include "varint.h"
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uintmax_t decode_varint(const unsigned char **bufp)
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{
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	const unsigned char *buf = *bufp;
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	unsigned char c = *buf++;
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	uintmax_t val = c & 127;
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	while (c & 128) {
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		val += 1;
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		if (!val || MSB(val, 7))
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			return 0; /* overflow */
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		c = *buf++;
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		val = (val << 7) + (c & 127);
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	}
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	*bufp = buf;
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	return val;
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}
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int encode_varint(uintmax_t value, unsigned char *buf)
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{
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	unsigned char varint[16];
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	unsigned pos = sizeof(varint) - 1;
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	varint[pos] = value & 127;
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	while (value >>= 7)
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		varint[--pos] = 128 | (--value & 127);
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	if (buf)
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		memcpy(buf, varint + pos, sizeof(varint) - pos);
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	return sizeof(varint) - pos;
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}
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