proxy: redo libevent handling code

The event handling code was unoptimized and temporary; it was slated for
a rewrite for performance and non-critical bugs alone. However the old
code may be causing critical bugs so it's being rewritten now.

Fixes:
- backend disconnects are detected immediately instead of on the next
  time they are used.
- backend reconnects happen _after_ the retry timeout, not before
- use a persistent read handler and a temporary write handler to avoid
  constantly calling epoll_ctl syscalls for potential performance boost.

Updated some tests for proxyconfig.t as it was picking up the
disconnects immediately.

Unrelated to a timing issue I resolved to the benchmark.

1 files changed, 3 insertions, 1 deletions

diff --git a/proxy_lua.c b/proxy_lua.c
index 2d38b8e..e6b50ae 100644
--- a/proxy_lua.c
+++ b/proxy_lua.c
@@ -337,7 +337,9 @@ static mcp_backend_wrap_t *_mcplib_make_backendconn(lua_State *L, mcp_backend_la
     }
 
     // initialize libevent.
-    memset(&be->event, 0, sizeof(be->event));
+    memset(&be->main_event, 0, sizeof(be->main_event));
+    memset(&be->write_event, 0, sizeof(be->write_event));
+    memset(&be->timeout_event, 0, sizeof(be->timeout_event));
 
     // initialize the client
     be->client = malloc(mcmc_size(MCMC_OPTION_BLANK));