diff options
author | Pieter Wuille <pieter.wuille@gmail.com> | 2012-06-15 14:19:11 +0200 |
---|---|---|
committer | Pieter Wuille <pieter.wuille@gmail.com> | 2012-10-20 23:08:56 +0200 |
commit | 4d6144f97faf9d2a6c89f41d7d2360f21f0b71e2 (patch) | |
tree | 02f4f8d5cb22c9ca152e1cb55f9d62943ee5458e /src/key.cpp | |
parent | 43b7905e98d827df45e970dbaf5f08561ecc6cda (diff) | |
download | bitcoin-4d6144f97faf9d2a6c89f41d7d2360f21f0b71e2.tar.xz |
Compact serialization for variable-length integers
Variable-length integers: bytes are a MSB base-128 encoding of the number.
The high bit in each byte signifies whether another digit follows. To make
the encoding is one-to-one, one is subtracted from all but the last digit.
Thus, the byte sequence a[] with length len, where all but the last byte
has bit 128 set, encodes the number:
(a[len-1] & 0x7F) + sum(i=1..len-1, 128^i*((a[len-i-1] & 0x7F)+1))
Properties:
* Very small (0-127: 1 byte, 128-16511: 2 bytes, 16512-2113663: 3 bytes)
* Every integer has exactly one encoding
* Encoding does not depend on size of original integer type
Diffstat (limited to 'src/key.cpp')
0 files changed, 0 insertions, 0 deletions