#include "table/block_based/index_reader_common.h"
#include "block_cache.h"
namespace ROCKSDB_NAMESPACE {
Status BlockBasedTable::IndexReaderCommon::ReadIndexBlock(
const BlockBasedTable* table, FilePrefetchBuffer* prefetch_buffer,
const ReadOptions& read_options, bool use_cache, GetContext* get_context,
BlockCacheLookupContext* lookup_context,
CachableEntry<Block>* index_block) {
PERF_TIMER_GUARD(read_index_block_nanos);
assert(table != nullptr);
assert(index_block != nullptr);
assert(index_block->IsEmpty());
const Rep* const rep = table->get_rep();
assert(rep != nullptr);
const Status s = table->RetrieveBlock(
prefetch_buffer, read_options, rep->index_handle, rep->decompressor.get(),
&index_block->As<Block_kIndex>(), get_context, lookup_context,
false, use_cache,
false, true);
return s;
}
Status BlockBasedTable::IndexReaderCommon::GetOrReadIndexBlock(
GetContext* get_context, BlockCacheLookupContext* lookup_context,
CachableEntry<Block>* index_block, const ReadOptions& ro) const {
assert(index_block != nullptr);
if (!index_block_.IsEmpty()) {
index_block->SetUnownedValue(index_block_.GetValue());
return Status::OK();
}
return ReadIndexBlock(table_, nullptr, ro,
cache_index_blocks(), get_context, lookup_context,
index_block);
}
void BlockBasedTable::IndexReaderCommon::EraseFromCacheBeforeDestruction(
uint32_t uncache_aggressiveness) {
if (uncache_aggressiveness > 0) {
if (index_block_.IsCached()) {
index_block_.ResetEraseIfLastRef();
} else {
table()->EraseFromCache(table()->get_rep()->index_handle);
}
}
}
}