Method openROCached

core/src/main/java/io/questdb/std/FdCache.java:187–207

Opens file in read-only mode with caching support.

(LPSZ lpsz)

     * Opens file in read-only mode with caching support.
     */
    public synchronized long openROCached(LPSZ lpsz) {
        final FdCacheRecord holder = getFdCacheRecord(lpsz);
        if (holder == null) {
            // Failed to open
            return -1;
        }

        holder.count++;

        // find a unique key even if the index generator wrapped over
        long uniqROFd;
        int keyIndex;
        do {
            uniqROFd = Numbers.encodeLowHighInts(nextIndex(), holder.osFd);
            keyIndex = openFdMapByFd.keyIndex(uniqROFd);
        } while (keyIndex < 0);

        openFdMapByFd.putAt(keyIndex, uniqROFd, holder);

        return uniqROFd;
    }

    /**
     * Removes file path from cache when file is deleted.