| 197 | } |
| 198 | |
| 199 | char get(size_t pos) const override { |
| 200 | /* |
| 201 | auto self = const_cast<PushedSequentialImpl*>(this); |
| 202 | // We do not do this automatically because all variable width tokens: |
| 203 | // ENUM/STRING/BINARY/KEYWORD are stored as file offsets until a full |
| 204 | // entity instance is finalized. |
| 205 | if (this->shared_from_this().use_count() == 2) { |
| 206 | // only drop pages when there is only one active client. |
| 207 | // NB this->shared_from_this() increases count by 1 |
| 208 | self->drop_consumed_up_to(pos); |
| 209 | } |
| 210 | */ |
| 211 | |
| 212 | const size_t avail_end = size(); |
| 213 | if (pos >= avail_end) throw std::out_of_range("pushed backend: position not committed yet"); |
| 214 | |
| 215 | pos -= discarded_page_bytes_; |
| 216 | |
| 217 | size_t page_start = 0; |
| 218 | for (const auto& pg : pages_) { |
| 219 | if (pos < page_start + pg.data.size()) { |
| 220 | const size_t off = pos - page_start; |
| 221 | return pg.data[off]; |
| 222 | } else { |
| 223 | page_start += pg.data.size(); |
| 224 | } |
| 225 | } |
| 226 | |
| 227 | throw std::out_of_range("pushed backend: internal inconsistency"); |
| 228 | } |
| 229 | |
| 230 | void pushNextPage(const std::string& data) override { |
| 231 | FileReader::Page p; p.data.assign(data.data(), data.data() + data.size()); |