Method GetSoFunctionPtr

be/src/runtime/lib-cache.cc:142–179

}

Status LibCache::GetSoFunctionPtr(const string& hdfs_lib_file, const string& symbol,
    time_t exp_mtime, void** fn_ptr, LibCacheEntry** ent, bool quiet) {
  if (hdfs_lib_file.empty()) {
    // Just loading a function ptr in the current process. No need to take any locks.
    DCHECK(current_process_handle_ != nullptr);
    RETURN_IF_ERROR(DynamicLookup(current_process_handle_, symbol.c_str(), fn_ptr, quiet));
    return Status::OK();
  }

  LibCacheEntry* entry = nullptr;
  unique_lock<mutex> lock;
  if (ent != nullptr && *ent != nullptr) {
    // Reuse already-cached entry provided by user
    entry = *ent;
    unique_lock<mutex> l(entry->lock);
    lock.swap(l);
  } else {
    RETURN_IF_ERROR(GetCacheEntry(hdfs_lib_file, TYPE_SO, exp_mtime, &lock, &entry));
  }
  DCHECK(entry != nullptr);
  DCHECK_EQ(entry->type, TYPE_SO);
  LibCacheEntry::SymbolMap::iterator it = entry->symbol_cache.find(symbol);
  if (it != entry->symbol_cache.end()) {
    *fn_ptr = it->second;
  } else {
    RETURN_IF_ERROR(
        DynamicLookup(entry->shared_object_handle, symbol.c_str(), fn_ptr, quiet));
    entry->symbol_cache[symbol] = *fn_ptr;
  }

  DCHECK(*fn_ptr != nullptr);
  if (ent != nullptr && *ent == nullptr) {
    // Only set and increment user's entry if it wasn't already cached
    *ent = entry;
    ++(*ent)->use_count;
  }
  return Status::OK();
}

void LibCache::DecrementUseCount(LibCacheEntry* entry) {
  if (entry == nullptr) return;