From 4a64b4f07b4bb56a8e7d560f543a99d8ae92bf65 Mon Sep 17 00:00:00 2001
From: Joris Vink <joris@coders.se>
Date: Thu, 13 Jun 2019 12:59:17 +0200
Subject: [PATCH] Improve curl timeout handling.

In case libcurl instructs us to call the timeout function as soon
as possible (timeout == 0 in curl_timeout), don't try to be clever
with a timeout value of 10ms.

Instead call the timeout function once we get back in the worker
event loop. This makes things a lot snappier as we don't depend
on epoll/kqueue waiting for io for 10ms (which actually isn't 10ms...).
---
 include/kore/curl.h |  1 +
 src/curl.c          | 17 +++++++++++++++--
 src/worker.c        | 12 ++++++++++--
 3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/include/kore/curl.h b/include/kore/curl.h
index 5bf9083..6f4257c 100644
--- a/include/kore/curl.h
+++ b/include/kore/curl.h
@@ -67,6 +67,7 @@ extern u_int16_t	kore_curl_timeout;
 extern u_int64_t	kore_curl_recv_max;
 
 void	kore_curl_sysinit(void);
+void	kore_curl_do_timeout(void);
 void	kore_curl_run(struct kore_curl *);
 void	kore_curl_cleanup(struct kore_curl *);
 int	kore_curl_success(struct kore_curl *);
diff --git a/src/curl.c b/src/curl.c
index a082f5a..5c9446b 100644
--- a/src/curl.c
+++ b/src/curl.c
@@ -33,6 +33,7 @@ struct fd_cache {
 
 static void	curl_process(void);
 static void	curl_event_handle(void *, int);
+static void	curl_timeout(void *, u_int64_t);
 static int	curl_timer(CURLM *, long, void *);
 static int	curl_socket(CURL *, curl_socket_t, int, void *, void *);
 
@@ -43,6 +44,7 @@ static CURLM			*multi = NULL;
 static struct kore_timer	*timer = NULL;
 static struct kore_pool		fd_cache_pool;
 static char			user_agent[64];
+static int			timeout_immediate = 0;
 static LIST_HEAD(, fd_cache)	cache[FD_CACHE_BUCKETS];
 
 u_int16_t	kore_curl_timeout = KORE_CURL_TIMEOUT;
@@ -146,6 +148,13 @@ kore_curl_cleanup(struct kore_curl *client)
 	}
 }
 
+void
+kore_curl_do_timeout(void)
+{
+	while (timeout_immediate)
+		curl_timeout(NULL, kore_time_ms());
+}
+
 size_t
 kore_curl_tobuf(char *ptr, size_t size, size_t nmemb, void *udata)
 {
@@ -560,6 +569,8 @@ curl_timeout(void *uarg, u_int64_t now)
 static int
 curl_timer(CURLM *mctx, long timeout, void *arg)
 {
+	timeout_immediate = 0;
+
 	if (timeout < 0) {
 		if (timer != NULL) {
 			kore_timer_remove(timer);
@@ -573,8 +584,10 @@ curl_timer(CURLM *mctx, long timeout, void *arg)
 		timer = NULL;
 	}
 
-	if (timeout == 0)
-		timeout = 10;
+	if (timeout == 0) {
+		timeout_immediate = 1;
+		return (CURLM_OK);
+	}
 
 	timer = kore_timer_add(curl_timeout, timeout, mctx, KORE_TIMER_ONESHOT);
 
diff --git a/src/worker.c b/src/worker.c
index b11ab07..7f18158 100644
--- a/src/worker.c
+++ b/src/worker.c
@@ -49,6 +49,10 @@
 #include "python_api.h"
 #endif
 
+#if defined(KORE_USE_CURL)
+#include "curl.h"
+#endif
+
 #if !defined(WAIT_ANY)
 #define WAIT_ANY		(-1)
 #endif
@@ -471,14 +475,18 @@ kore_worker_entry(struct kore_worker *kw)
 			break;
 
 		kore_timer_run(now);
-
+#if defined(KORE_USE_CURL)
+		kore_curl_do_timeout();
+#endif
 #if !defined(KORE_NO_HTTP)
 		http_process();
 #endif
 #if defined(KORE_USE_PYTHON)
 		kore_python_coro_run();
 #endif
-
+#if defined(KORE_USE_CURL)
+		kore_curl_do_timeout();
+#endif
 		if (next_prune <= now) {
 			kore_connection_check_timeout(now);
 			kore_connection_prune(KORE_CONNECTION_PRUNE_DISCONNECT);