Reader::findMetadataStart runs forever on faulty files

[eteubert]

If the database file is faulty, findMetadataStart has to go through the whole file byte by byte, which is extremely slow and creates a timeout exception (for servers with default config of 30 seconds timeout).

I know I can (and probably should) check for the validity of the database file before using the reader. However, it would be nice if it could handle that case more gracefully.

[oschwald]

Per the MaxMind DB spec, the metadata will always be in the last 128 KB. We should probably just stop searching at that point.

[eteubert]

I am still hoping for a patch :)

Is it as simple as changing the outer search loop?

// from this
for ($i = 0; $i < $fileSize - $markerLength + 1; $i++) {

// ... to this?
for ($i = 0; $i < 128000 + 1; $i++) {

[oschwald]

You'd want the minimum the current number and 128k as a file could be less than 128k.