Merge #14934: Descriptor expansion cache clarifications

2e68ffaf20 [doc] descriptor: explain GetPubKey() usage with cached public key (Sjors Provoost)
2290269759 scripted-diff: rename DescriptorImpl m_script_arg to m_subdescriptor_arg (Sjors Provoost)

Pull request description:

  I found the name `m_script_arg` to be confusing while reviewing https://github.com/bitcoin/bitcoin/pull/14646#discussion_r240677238. @sipa let me know if `m_subdescriptor_arg` is completely wrong.

  I also added an explanation of why we call `GetPubKey` when we don't ask it for a public key.

ACKs for top commit:
  laanwj:
    ACK 2e68ffaf20

Tree-SHA512: 06698e9a91cdda93c043a82732793f0ad3cd91daa2513565953e9fa048d5573322fb534e9d0ea9ab736e6366be5921e2b8699c4f4b3693edab48039aaae06f78
This commit is contained in:
Wladimir J. van der Laan
2019-08-14 13:30:23 +02:00
2 changed files with 21 additions and 17 deletions

View File

@@ -47,9 +47,9 @@ struct Descriptor {
*
* pos: the position at which to expand the descriptor. If IsRange() is false, this is ignored.
* provider: the provider to query for private keys in case of hardened derivation.
* output_script: the expanded scriptPubKeys will be put here.
* output_scripts: the expanded scriptPubKeys will be put here.
* out: scripts and public keys necessary for solving the expanded scriptPubKeys will be put here (may be equal to provider).
* cache: vector which will be overwritten with cache data necessary to-evaluate the descriptor at this point without access to private keys.
* cache: vector which will be overwritten with cache data necessary to evaluate the descriptor at this point without access to private keys.
*/
virtual bool Expand(int pos, const SigningProvider& provider, std::vector<CScript>& output_scripts, FlatSigningProvider& out, std::vector<unsigned char>* cache = nullptr) const = 0;
@@ -57,7 +57,7 @@ struct Descriptor {
*
* pos: the position at which to expand the descriptor. If IsRange() is false, this is ignored.
* cache: vector from which cached expansion data will be read.
* output_script: the expanded scriptPubKeys will be put here.
* output_scripts: the expanded scriptPubKeys will be put here.
* out: scripts and public keys necessary for solving the expanded scriptPubKeys will be put here (may be equal to provider).
*/
virtual bool ExpandFromCache(int pos, const std::vector<unsigned char>& cache, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const = 0;