git/varint.c
Junio C Hamano d2c1898571 varint: make it available outside the context of pack
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-03 16:24:44 -07:00

30 lines
631 B
C

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