From: bones_was_here <bones_was_here@xonotic.au>
Date: Sat, 21 Jan 2023 01:49:27 +0000 (+1000)
Subject: Improve client/listen curl transfer speed at low FPS
X-Git-Url: https://git.xonotic.org/?a=commitdiff_plain;h=025fbac31da7f654e296e20b3037b5ce88074f8b;hp=a2bb7fbbe9c477aaa2ebb4d9aaa2fa0423dd6f0a;p=xonotic%2Fdarkplaces.git

Improve client/listen curl transfer speed at low FPS

This is a huge boost for some libcurl versions, eg 7.74 in Debian 11

Fixes https://gitlab.com/xonotic/darkplaces/-/issues/375

Signed-off-by: bones_was_here <bones_was_here@xonotic.au>
---

diff --git a/cl_main.c b/cl_main.c
index 2f00941e..dd2ea6a5 100644
--- a/cl_main.c
+++ b/cl_main.c
@@ -2814,6 +2814,11 @@ double CL_Frame (double time)
 	SndSys_SendKeyEvents();
 	Sys_SendKeyEvents();
 
+	/*
+	 * If the accumulator hasn't become positive, don't
+	 * run the frame. Everything that happens before this
+	 * point will happen even if we're sleeping this frame.
+	 */
 	if((cl_timer += time) < 0)
 		return cl_timer;
 
diff --git a/host.c b/host.c
index aa8fb4c3..e34f712b 100644
--- a/host.c
+++ b/host.c
@@ -681,7 +681,11 @@ static inline void Host_Sleep(double time)
 		// TODO can we do the same for ServerFrame? Probably not.
 	}
 	else
+	{
+		if (cls.state != ca_dedicated)
+			Curl_Select(&time);
 		Sys_Sleep((int)time);
+	}
 	delta = Sys_DirtyTime() - time0;
 	if (delta < 0 || delta >= 1800)
 		delta = 0;
diff --git a/libcurl.c b/libcurl.c
index 3ad3c5ff..53674299 100644
--- a/libcurl.c
+++ b/libcurl.c
@@ -158,6 +158,7 @@ static const char * (*qcurl_easy_strerror) (CURLcode);
 
 static CURLM * (*qcurl_multi_init) (void);
 static CURLMcode (*qcurl_multi_perform) (CURLM *multi_handle, int *running_handles);
+static CURLMcode (*qcurl_multi_poll) (CURLM *multi_handle, void*, unsigned int extra_nfds, int timeout_ms, int *ret);
 static CURLMcode (*qcurl_multi_add_handle) (CURLM *multi_handle, CURL *easy_handle);
 static CURLMcode (*qcurl_multi_remove_handle) (CURLM *multi_handle, CURL *easy_handle);
 static CURLMsg * (*qcurl_multi_info_read) (CURLM *multi_handle, int *msgs_in_queue);
@@ -177,6 +178,7 @@ static dllfunction_t curlfuncs[] =
 	{"curl_easy_getinfo",		(void **) &qcurl_easy_getinfo},
 	{"curl_multi_init",			(void **) &qcurl_multi_init},
 	{"curl_multi_perform",		(void **) &qcurl_multi_perform},
+	{"curl_multi_poll",		(void **) &qcurl_multi_poll},
 	{"curl_multi_add_handle",	(void **) &qcurl_multi_add_handle},
 	{"curl_multi_remove_handle",(void **) &qcurl_multi_remove_handle},
 	{"curl_multi_info_read",	(void **) &qcurl_multi_info_read},
@@ -432,6 +434,8 @@ static size_t CURL_fwrite(void *data, size_t size, size_t nmemb, void *vdi)
 
 	di->bytes_received += bytes;
 
+	//Con_Printf("CURL_fwrite callback timestamp: %f bytes: %ld\n", host.realtime, ret);
+
 	return ret;
 	// Why not ret / nmemb?
 	// Because CURLOPT_WRITEFUNCTION docs say to return the number of bytes.
@@ -1235,6 +1239,25 @@ void Curl_Frame(void)
 	if (curl_mutex) Thread_UnlockMutex(curl_mutex);
 }
 
+/*
+====================
+Curl_Select
+
+Sleeps until there's some transfer progress or a timeout is reached,
+unfortunately the timeout is only in milliseconds.
+This allows good throughput even at very low FPS.
+====================
+*/
+void Curl_Select(double *microseconds)
+{
+	if (List_Is_Empty(&downloads))
+		return;
+	if (qcurl_multi_poll(curlm, NULL, 0, *microseconds / 1000, NULL) == CURLM_OK)
+		*microseconds = 0; // either we finished waiting or a transfer progressed
+	else
+		Con_Print("There's an emergency going on!\nIt's still going on!\nMaybe you need to upgrade libcurl?\n");
+}
+
 /*
 ====================
 Curl_CancelAll
diff --git a/libcurl.h b/libcurl.h
index d960be8a..21b8c6fe 100644
--- a/libcurl.h
+++ b/libcurl.h
@@ -14,6 +14,7 @@ typedef void (*curl_callback_t) (int status, size_t length_received, unsigned ch
 // code is one of the CURLCBSTATUS constants, or the HTTP error code (when > 0).
 
 void Curl_Frame(void);
+void Curl_Select(double *microseconds);
 qbool Curl_Running(void);
 qbool Curl_Begin_ToFile(const char *URL, double maxspeed, const char *name, int loadtype, qbool forthismap);