This is a cleaned up version of JoelKatz’ work, originally found in pull request #568.
A few minor didnt-check-error-return bugs were fixed. All other changes were comment- or coding style-related changes unrelated to behavior.
Should be upstream-ready at this point. Is in use at a few pools and other places.
There is no limit to the threads spawned – but note that threads are spawned only after checking the IP filter list.
The first resource likely to be exhausted is a thread-group or systemwide thread limit, not memory. But yes, if you pass the IP filter list, that can be DoS’d.
Should not be a problem to add a simple simultaneous-threads limit here, though.
Still getting an error:
bitcoinrpc.cpp: In function ‘void ThreadRPCServer3(void*)’: bitcoinrpc.cpp:2610: warning: suggest a space before ‘;’ or explicit braces around empty body in ‘while’ statement
Line 2610 is: while (0);
… which looks to me like it should be deleted, since loop is defined as: for(;;) in util.h
Change internal HTTP JSON-RPC server from single-threaded to
thread-per-connection model. The IP filter list is applied prior to starting
the thread, which then processes the RPC.
A mutex covers the entire RPC operation, because not all RPC operations are
thread-safe.
[minor modifications by jgarzik, to make change upstream-ready]
2599 }
2600 }
2601 catch (Object& objError)
2602 {
2603- ErrorReply(stream, objError, id);
2604+ ErrorReply(conn->stream, objError, id);
2605+ break;
2606 }
2607 catch (std::exception& e)
2608 {
2609- ErrorReply(stream, JSONRPCError(-32700, e.what()), id);
2610+ ErrorReply(conn->stream, JSONRPCError(-32700, e.what()), id);