From: bones_was_here <bones_was_here@xonotic.au>
Date: Sat, 9 Dec 2023 07:49:56 +0000 (+1000)
Subject: cbuf: recycle node after it executes, clear commands on Host_Error()
X-Git-Url: http://git.xonotic.org/?a=commitdiff_plain;h=7e1f7d12f57c064a6855d9850d28387ca6092c45;p=xonotic%2Fdarkplaces.git

cbuf: recycle node after it executes, clear commands on Host_Error()

This reverts 626658074c8dd5c2288becd836103e2efdb9b741 which looks like a
potentially racy or non-threadsafe approach, and instead prevents
problems by clearing the command buffers if Host_Error() is called and
doesn't shut down DP.

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

diff --git a/cmd.c b/cmd.c
index 66dfaa82..e1e2c0a0 100644
--- a/cmd.c
+++ b/cmd.c
@@ -406,10 +406,7 @@ void Cbuf_Execute (cmd_buf_t *cbuf)
 		 * can insert data at the beginning of the text buffer
 		 */
 		current = List_Entry(cbuf->start.next, cmd_input_t, list);
-		
-		// Recycle memory so using WASD doesn't cause a malloc and free
-		List_Move_Tail(&current->list, &cbuf->free);
-		
+
 		/*
 		 * Assume we're rolling with the current command-line and
 		 * always set this false because alias expansion or cbuf insertion
@@ -434,6 +431,9 @@ void Cbuf_Execute (cmd_buf_t *cbuf)
 			Cmd_ExecuteString (current->source, current->text, src_local, false);
 		}
 
+		// Recycle memory so using WASD doesn't cause a malloc and free
+		List_Move_Tail(&current->list, &cbuf->free);
+
 		current = NULL;
 
 		if (cbuf->wait)
@@ -449,11 +449,7 @@ void Cbuf_Execute (cmd_buf_t *cbuf)
 		if (++i == 1000000 && prvm_runawaycheck)
 		{
 			Con_Printf(CON_WARN "Cbuf_Execute: runaway loop counter hit limit of %d commands, clearing command buffers!\n", i);
-			while (!List_Is_Empty(&cbuf->start))
-				List_Move_Tail(cbuf->start.next, &cbuf->free);
-			while (!List_Is_Empty(&cbuf->deferred))
-				List_Move_Tail(cbuf->deferred.next, &cbuf->free);
-			cbuf->size = 0;
+			Cbuf_Clear(cbuf);
 		}
 	}
 }
@@ -492,6 +488,15 @@ void Cbuf_Frame(cmd_buf_t *cbuf)
 //	R_TimeReport("console");
 }
 
+void Cbuf_Clear(cmd_buf_t *cbuf)
+{
+	while (!List_Is_Empty(&cbuf->start))
+		List_Move_Tail(cbuf->start.next, &cbuf->free);
+	while (!List_Is_Empty(&cbuf->deferred))
+		List_Move_Tail(cbuf->deferred.next, &cbuf->free);
+	cbuf->size = 0;
+}
+
 /*
 ==============================================================================
 
diff --git a/cmd.h b/cmd.h
index 99241fcf..b3502919 100644
--- a/cmd.h
+++ b/cmd.h
@@ -199,6 +199,8 @@ void Cbuf_InsertText (cmd_state_t *cmd, const char *text);
 void Cbuf_Execute (cmd_buf_t *cbuf);
 /*! Performs deferred commands and runs Cbuf_Execute, called by Host_Frame */
 void Cbuf_Frame (cmd_buf_t *cbuf);
+/// Clears all command buffers
+void Cbuf_Clear(cmd_buf_t *cbuf);
 
 //===========================================================================
 
diff --git a/host.c b/host.c
index 3e2c5f99..e7dd4a42 100644
--- a/host.c
+++ b/host.c
@@ -133,6 +133,9 @@ void Host_Error (const char *error, ...)
 	if (cls.state == ca_dedicated)
 		Sys_Error ("Host_Error: %s",hosterrorstring2);	// dedicated servers exit
 
+	// prevent an endless loop if the error was triggered by a command
+	Cbuf_Clear(cmd_local->cbuf);
+
 	CL_Disconnect();
 	cls.demonum = -1;