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/*
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* Copyright (C) the libgit2 contributors. All rights reserved.
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*
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* This file is part of libgit2, distributed under the GNU GPL v2 with
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* a Linking Exception. For full terms see the included COPYING file.
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*/
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#include "varint.h"
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uintmax_t git_decode_varint(const unsigned char *bufp, size_t *varint_len)
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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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37 |
2,7 |
while (c & 128) {
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val += 1;
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if (!val || MSB(val, 7)) {
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/* This is not a valid varint_len, so it signals
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the error */
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*varint_len = 0;
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return 0; /* overflow */
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}
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c = *buf++;
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val = (val << 7) + (c & 127);
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}
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*varint_len = buf - bufp;
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return val;
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}
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int git_encode_varint(unsigned char *buf, size_t bufsize, uintmax_t value)
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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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if (bufsize < (sizeof(varint) - pos))
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return -1;
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memcpy(buf, varint + pos, sizeof(varint) - pos);
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}
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return sizeof(varint) - pos;
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}
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