Fix infinite loop in case an invalid pk3 file has been downloaded from the server. Thanks tjw for reporting (#3074)

code/client/cl_curl.c

@@ -332,8 +332,7 @@ void CL_cURL_PerformDownload(void)
 			qcurl_easy_strerror(msg->data.result),
 			code, clc.downloadURL);
 	}
-	*clc.downloadTempName = *clc.downloadName = 0;
-	Cvar_Set( "cl_downloadName", "" );
+
 	CL_NextDownload();
 }
 #endif /* USE_CURL */

code/client/cl_main.c

@@ -1916,11 +1916,25 @@ CL_NextDownload
 A download completed or failed
 =================
 */
-void CL_NextDownload(void) {
+void CL_NextDownload(void)
+{
 	char *s;
 	char *remoteName, *localName;
 	qboolean useCURL = qfalse;
 
+	// A download has finished, check whether this matches a referenced checksum
+	if(*clc.downloadName)
+	{
+		char *zippath = FS_BuildOSPath(Cvar_VariableString("fs_homepath"), clc.downloadName, "");
+		zippath[strlen(zippath)-1] = '\0';
+
+		if(!FS_CompareZipChecksum(zippath))
+			Com_Error(ERR_DROP, "Incorrect checksum for file: %s", clc.downloadName);
+	}
+
+	*clc.downloadTempName = *clc.downloadName = 0;
+	Cvar_Set("cl_downloadName", "");
+
 	// We are looking to start a download here
 	if (*clc.downloadList) {
 		s = clc.downloadList;
@@ -2027,6 +2041,10 @@ void CL_InitDownloads(void) {
 		if ( *clc.downloadList ) {
 			// if autodownloading is not enabled on the server
 			cls.state = CA_CONNECTED;
+
+			*clc.downloadTempName = *clc.downloadName = 0;
+			Cvar_Set( "cl_downloadName", "" );
+
 			CL_NextDownload();
 			return;
 		}

code/client/cl_parse.c

@@ -619,8 +619,6 @@ void CL_ParseDownload ( msg_t *msg ) {
 			// rename the file
 			FS_SV_Rename ( clc.downloadTempName, clc.downloadName );
 		}
-		*clc.downloadTempName = *clc.downloadName = 0;
-		Cvar_Set( "cl_downloadName", "" );
 
 		// send intentions now
 		// We need this because without it, we would hold the last nextdl and then start