From 733d21810f10c5eaccc7cf6c90e2629d3210a219 Mon Sep 17 00:00:00 2001
From: divverent <divverent@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Thu, 8 Jan 2009 19:06:17 +0000
Subject: [PATCH] Add a comment explaining how the compression algorithms are
 negotiated

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@8639 d7cf8633-e32d-0410-b094-e92efae38249
---
 cl_parse.c |  2 +-
 sv_main.c  | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/cl_parse.c b/cl_parse.c
index 55b832ef..9bf28867 100644
--- a/cl_parse.c
+++ b/cl_parse.c
@@ -995,7 +995,7 @@ void CL_BeginDownloads(qboolean aborteddownload)
 		 && !FS_FileExists(va("dlcache/%s.%i.%i", csqc_progname.string, csqc_progsize.integer, csqc_progcrc.integer)))
 		{
 			Con_Printf("Downloading new CSQC code to dlcache/%s.%i.%i\n", csqc_progname.string, csqc_progsize.integer, csqc_progcrc.integer);
-			if(cl_serverextension_download.integer >= 2 && FS_HasZlib())
+			if(cl_serverextension_download.integer == 2 && FS_HasZlib())
 				Cmd_ForwardStringToServer(va("download %s deflate", csqc_progname.string));
 			else
 				Cmd_ForwardStringToServer(va("download %s", csqc_progname.string));
diff --git a/sv_main.c b/sv_main.c
index e0fd7e76..c35976fe 100644
--- a/sv_main.c
+++ b/sv_main.c
@@ -2121,6 +2121,31 @@ static void SV_StartDownload_f(void)
 		host_client->download_started = true;
 }
 
+/*
+ * Compression extension negotiation:
+ *
+ * Server to client:
+ *   cl_serverextension_download 2
+ *
+ * Client to server:
+ *   download <filename> <list of zero or more suppported compressions in order of preference>
+ * e.g.
+ *   download maps/map1.bsp lzo deflate huffman
+ *
+ * Server to client:
+ *   cl_downloadbegin <compressed size> <filename> <compression method actually used>
+ * e.g.
+ *   cl_downloadbegin 123456 maps/map1.bsp deflate
+ *
+ * The server may choose not to compress the file by sending no compression name, like:
+ *   cl_downloadbegin 345678 maps/map1.bsp
+ *
+ * NOTE: the "download" command may only specify compression algorithms if
+ *       cl_serverextension_download is 2!
+ *       If cl_serverextension_download has a different value, the client must
+ *       assume this extension is not supported!
+ */
+
 static void Download_CheckExtensions(void)
 {
 	int i;
-- 
2.39.2