mod_cgi: make read buffer as big as incoming data block

git-svn-id: svn://svn.lighttpd.net/lighttpd/branches/lighttpd-1.4.x@2778 152afb58-edef-0310-8abb-c4023f1b3aa9

NEWS

@@ -6,6 +6,7 @@ NEWS
 - 1.4.29 -
   * Fix mod_proxy waiting for response even if content-length is 0 (fixes #2259)
   * Silence annoying "connection closed: poll() -> ERR" error.log message (fixes #2257)
+  * mod_cgi: make read buffer as big as incoming data block
 
 - 1.4.28 - 2010-08-22
   * Rename fdevent_event_add to _set to reflect what the function does. Fix some handlers. (fixes #2249)

src/mod_cgi.c

@@ -341,8 +341,19 @@ static int cgi_demux_response(server *srv, handler_ctx *hctx) {
 
 	while(1) {
 		int n;
+		int toread;
+
+#if defined(__WIN32)
+		buffer_prepare_copy(hctx->response, 4 * 1024);
+#else
+		if (ioctl(con->fd, FIONREAD, &toread) || toread == 0 || toread <= 4*1024) {
+			buffer_prepare_copy(hctx->response, 4 * 1024);
+		} else {
+			if (toread > MAX_READ_LIMIT) toread = MAX_READ_LIMIT;
+			buffer_prepare_copy(hctx->response, toread + 1);
+		}
+#endif
 
-		buffer_prepare_copy(hctx->response, 1024);
 		if (-1 == (n = read(hctx->fd, hctx->response->ptr, hctx->response->size - 1))) {
 			if (errno == EAGAIN || errno == EINTR) {
 				/* would block, wait for signal */