| 2305 | } |
| 2306 | |
| 2307 | uint64_t StreamIndexedIO::Index::allocate( uint64_t sz ) |
| 2308 | { |
| 2309 | uint64_t loc = 0; |
| 2310 | |
| 2311 | FreePagesSizeMap::iterator it = m_freePagesSize.find( sz ); |
| 2312 | |
| 2313 | if (it == m_freePagesSize.end()) |
| 2314 | { |
| 2315 | it = m_freePagesSize.upper_bound( sz ); |
| 2316 | } |
| 2317 | |
| 2318 | if (it != m_freePagesSize.end()) |
| 2319 | { |
| 2320 | assert( it->first >= sz ); |
| 2321 | assert( m_freePagesOffset.find(it->second->m_offset) != m_freePagesOffset.end() ); |
| 2322 | |
| 2323 | uint64_t pageSize = it->first; |
| 2324 | FreePage *page = it->second; |
| 2325 | |
| 2326 | assert( page ); |
| 2327 | assert( page->m_size == it->first ); |
| 2328 | |
| 2329 | pageSize -= sz; |
| 2330 | |
| 2331 | if (pageSize == 0) |
| 2332 | { |
| 2333 | /// Page now used entirely, so delete from the free pages list |
| 2334 | m_freePagesSize.erase(it); |
| 2335 | m_freePagesOffset.erase( page->m_offset ); |
| 2336 | |
| 2337 | assert( m_freePagesOffset.size() == m_freePagesSize.size() ); |
| 2338 | |
| 2339 | loc = page->m_offset; |
| 2340 | delete page; |
| 2341 | } |
| 2342 | else |
| 2343 | { |
| 2344 | /// Adjust the page to account for the consumed space, and reinsert into the sorted structures |
| 2345 | m_freePagesSize.erase( it ); |
| 2346 | m_freePagesOffset.erase( page->m_offset ); |
| 2347 | |
| 2348 | assert( m_freePagesOffset.size() == m_freePagesSize.size() ); |
| 2349 | |
| 2350 | loc = page->m_offset; |
| 2351 | |
| 2352 | addFreePage( page->m_offset+sz, page->m_size-sz ); |
| 2353 | |
| 2354 | delete page; |
| 2355 | |
| 2356 | |
| 2357 | } |
| 2358 | |
| 2359 | assert( m_freePagesOffset.size() == m_freePagesSize.size() ); |
| 2360 | } |
| 2361 | else |
| 2362 | { |
| 2363 | loc = m_next; |
| 2364 | |