Skip to content

Instantly share code, notes, and snippets.

Show Gist options
  • Save itoonx/3754906d179355affdca4630d045c71c to your computer and use it in GitHub Desktop.
Save itoonx/3754906d179355affdca4630d045c71c to your computer and use it in GitHub Desktop.
/** pruned version of CTransaction: only retains metadata and unspent transaction outputs
*
* Serialized format:
* - VARINT(nVersion)
* - VARINT(nCode)
* - unspentness bitvector, for vout[2] and further; least significant byte first
* - the non-spent CTxOuts (via CTxOutCompressor)
* - VARINT(nHeight)
*
* The nCode value consists of:
* - bit 1: IsCoinBase()
* - bit 2: vout[0] is not spent
* - bit 4: vout[1] is not spent
* - The higher bits encode N, the number of non-zero bytes in the following bitvector.
* - In case both bit 2 and bit 4 are unset, they encode N-1, as there must be at
* least one non-spent output).
*
* Example: 0104835800816115944e077fe7c803cfa57f29b36bf87c1d358bb85e
* <><><--------------------------------------------><---->
* | \ | /
* version code vout[1] height
*
* - version = 1
* - code = 4 (vout[1] is not spent, and 0 non-zero bytes of bitvector follow)
* - unspentness bitvector: as 0 non-zero bytes follow, it has length 0
* - vout[1]: 835800816115944e077fe7c803cfa57f29b36bf87c1d35
* * 8358: compact amount representation for 60000000000 (600 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 816115944e077fe7c803cfa57f29b36bf87c1d35: address uint160
* - height = 203998
*
*
* Example: 0109044086ef97d5790061b01caab50f1b8e9c50a5057eb43c2d9563a4eebbd123008c988f1a4a4de2161e0f50aac7f17e7f9555caa486af3b
* <><><--><--------------------------------------------------><----------------------------------------------><---->
* / \ \ | | /
* version code unspentness vout[4] vout[16] height
*
* - version = 1
* - code = 9 (coinbase, neither vout[0] or vout[1] are unspent,
* 2 (1, +1 because both bit 2 and bit 4 are unset) non-zero bitvector bytes follow)
* - unspentness bitvector: bits 2 (0x04) and 14 (0x4000) are set, so vout[2+2] and vout[14+2] are unspent
* - vout[4]: 86ef97d5790061b01caab50f1b8e9c50a5057eb43c2d9563a4ee
* * 86ef97d579: compact amount representation for 234925952 (2.35 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 61b01caab50f1b8e9c50a5057eb43c2d9563a4ee: address uint160
* - vout[16]: bbd123008c988f1a4a4de2161e0f50aac7f17e7f9555caa4
* * bbd123: compact amount representation for 110397 (0.001 BTC)
* * 00: special txout type pay-to-pubkey-hash
* * 8c988f1a4a4de2161e0f50aac7f17e7f9555caa4: address uint160
* - height = 120891
*/
@itoonx
Copy link
Author

itoonx commented Mar 3, 2019

SegWit input scriptSigs will have one of these patterns:

0x160014<20 bytes> (P2WPKH)
0x220020<32 bytes> (P2WSH)

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment