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MoreBC2

src/hash.h

CategoryDeveloper / Source AtlasStatusReviewed / Source-confirmed structuralLast reviewed2026-09-12

Purpose

Section titled “Purpose”

src/hash.h defines hashing helpers used throughout BitcoinII Core. For current MoreBC2 documentation it is an important source anchor for the double-SHA256 block-header hashing path.

Current reviewed behavior

Section titled “Current reviewed behavior”

Release-pinned/current review establishes:

  • CHash256 implements the double-SHA256 construction used by Bitcoin-style 256-bit hashing helpers;
  • HashWriter::GetHash() finalizes SHA-256, resets/writes the first digest, and finalizes SHA-256 again;
  • HashWriter::GetSHA256() exposes a single-SHA256 result;
  • CBlockHeader::GetHash() routes through HashWriter::GetHash().

Accordingly, MoreBC2 uses double-SHA256 (or SHA-256d where context makes that abbreviation clear) for BitcoinII block-header proof-of-work wording.

v31 boundary

Section titled “v31 boundary”

BitcoinII Core v31.1.0 changes current mining behavior through ShockWave difficulty calculation, not by replacing the block-header hash function.

The distinction matters:

  • hashing answers whether a candidate header hash satisfies its target;
  • ShockWave determines the target/nBits required for the next candidate block from height 57750;
  • accumulated chain work determines best-chain selection among valid candidates.

Do not describe “SHA-256 compatibility” as proof that generic Bitcoin mining/template software is fully BC2-compatible. Candidate-time/required-work behavior must also be correct.

Other hashing helpers

Section titled “Other hashing helpers”

The file also contains single-SHA256 and SHA-256/RIPEMD-160-related helpers used elsewhere in Bitcoin-style key/script/data processing. This page does not attempt to enumerate every call site.

Section titled “Related pages”

Primary source

Section titled “Primary source”
  • BitcoinII Core v31.1.0/src/hash.h

Canonical tag: https://github.com/Bitcoin-II/BitcoinII-Core/tree/v31.1.0

Verification

Section titled “Verification”

Status: Reviewed / Source-confirmed structural
Primary evidence: BitcoinII Core v31.1.0 hash and block-primitives paths
Notes: Double-SHA256 block-header hashing is source-confirmed. This page does not claim a runtime benchmark, source-build reproduction, or blanket third-party miner compatibility.