Change Details

> tests: Set errno in FuzzedFileProvider. Implement seek(..., ..., SEEK_END). > validation: Make DumpMempool(...) and LoadMempool(...) easier to test/fuzz/mock > tests: Add fuzzing harness for LoadMempool(...) and DumpMempool(...) This is a backport of core#19259 With minor changes from other PRs backported out of sequence or not yet backported: - core#21866: `::Chainstateactive()` no longer exists - core#25290: mempool constructor now takes a `MemPoolOptions` parameter - core#19065: `ConsumeTime` helper function

> tests: Set errno in FuzzedFileProvider. Implement seek(..., ..., SEEK_END). > validation: Make DumpMempool(...) and LoadMempool(...) easier to test/fuzz/mock > tests: Add fuzzing harness for LoadMempool(...) and DumpMempool(...) This is a backport of [[https://github.com/bitcoin/bitcoin/pull/19259 | core#19259]] With minor changes from other PRs backported out of sequence or not yet backported: - [[https://github.com/bitcoin/bitcoin/pull/21866 | core#21866]]: `::Chainstateactive()` no longer exists - [[https://github.com/bitcoin/bitcoin/pull/25290 | core#25290]]: mempool constructor now takes a `MemPoolOptions` parameter - [[https://github.com/bitcoin/bitcoin/pull/19065 | core#19065]]: `ConsumeTime` helper function

> tests: Set errno in FuzzedFileProvider. Implement seek(..., ..., SEEK_END). > validation: Make DumpMempool(...) and LoadMempool(...) easier to test/fuzz/mock > tests: Add fuzzing harness for LoadMempool(...) and DumpMempool(...) This is a backport of [[https://github.com/bitcoin/bitcoin/pull/19259 | core#19259]] With minor changes from other PRs backported out of sequence or not yet backported: -- [[https://github.com/bitcoin/bitcoin/pull/21866 | core#21866:]]: `::Chainstateactive()` no longer exists -- [[https://github.com/bitcoin/bitcoin/pull/25290 | core#25290:]]: mempool constructor now takes a `MemPoolOptions` parameter -- [[https://github.com/bitcoin/bitcoin/pull/19065 | core#19065]]: `ConsumeTime` helper function