LSC process hangs indefinitely when ouput overflow the available buffer

[soisik]

During the clean phase, if the LIST script returns many entries, LSC will stop reading and hangs indefinitely.

Cause is explained in this SOF answer : https://stackoverflow.com/a/5483880:

the process is blocked as soon as the buffer is full and waits for your process to continue reading. Your process in turn waits for the other process to finish (which it won't because it waits for your process, ...). This is a classical deadlock situation. You need to continually read from the processes input stream to ensure that it doesn't block.

The problem is located in AbstractExecutableLdifService.execute(String[] runtime, String[] env, String input, StringBuffer datas) method: p.waitFor(); is called before p.getInputStream() is invoked, and inputstream is not read using BufferedReader.

Many thanks to Lior Dotan who has first reported this issue on LSC ML https://www.mail-archive.com/[email protected]/msg03763.html.

PR is following.