highperfocused/bitcoin
1
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2026-06-03 09:43:55 +02:00
Code Issues Packages Projects Releases Wiki Activity

wallet: Add DatabaseBatch::ErasePrefix method

Browse Source 
This new function is not used yet this commit, but next commit adds usages and
test coverage for both BDB and sqlite.
This commit is contained in:
Ryan Ofsky
2020-04-12 13:40:43 -04:00
parent cae0608ad4
commit 5938ad0bdb
6 changed files with 51 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/wallet/bdb.cpp
View File

@@ -665,12 +665,14 @@ void BerkeleyDatabase::ReloadDbEnv()
env->ReloadDbEnv();
}
BerkeleyCursor::BerkeleyCursor(BerkeleyDatabase& database)
BerkeleyCursor::BerkeleyCursor(BerkeleyDatabase& database, BerkeleyBatch* batch)
{
if (!database.m_db.get()) {
throw std::runtime_error(STR_INTERNAL_BUG("BerkeleyDatabase does not exist"));
}
int ret = database.m_db->cursor(nullptr, &m_cursor, 0);
// Transaction argument to cursor is only needed when using the cursor to
// write to the database. Read-only cursors do not need a txn pointer.
int ret = database.m_db->cursor(batch ? batch->txn() : nullptr, &m_cursor, 0);
if (ret != 0) {
throw std::runtime_error(STR_INTERNAL_BUG(strprintf("BDB Cursor could not be created. Returned %d", ret)));
}
@@ -817,6 +819,25 @@ bool BerkeleyBatch::HasKey(DataStream&& key)
return ret == 0;
}
bool BerkeleyBatch::ErasePrefix(Span<const std::byte> prefix)
{
if (!TxnBegin()) return false;
auto cursor{std::make_unique<BerkeleyCursor>(m_database, this)};
// const_cast is safe below even though prefix_key is an in/out parameter,
// because we are not using the DB_DBT_USERMEM flag, so BDB will allocate
// and return a different output data pointer
Dbt prefix_key{const_cast<std::byte*>(prefix.data()), static_cast<uint32_t>(prefix.size())}, prefix_value{};
int ret{cursor->dbc()->get(&prefix_key, &prefix_value, DB_SET_RANGE)};
for (int flag{DB_CURRENT}; ret == 0; flag = DB_NEXT) {
SafeDbt key, value;
ret = cursor->dbc()->get(key, value, flag);
if (ret != 0 || key.get_size() < prefix.size() || memcmp(key.get_data(), prefix.data(), prefix.size()) != 0) break;
ret = cursor->dbc()->del(0);
}
cursor.reset();
return TxnCommit() && (ret == 0 || ret == DB_NOTFOUND);
}
void BerkeleyDatabase::AddRef()
{
LOCK(cs_db);