tweaks: set the file format only when unset, so it doesn't need saving

When inserting a file into the current buffer, the 'fmt' element will
already be set.  When we avoid overwriting the current value of 'fmt'
(when it's other than UNSPECIFIED), we don't need to save and restore
the value when inserting a file.

src/files.c

@@ -824,10 +824,6 @@ void read_file(FILE *f, int fd, const char *filename, bool undoable)
 		statusline(HUSH, P_("Read %zu line", "Read %zu lines",
 						num_lines), num_lines);
 
-#ifndef NANO_TINY
-	openfile->fmt = format;
-#endif
-
 	/* If we inserted less than a screenful, don't center the cursor. */
 	if (undoable && less_than_a_screenful(was_lineno, was_leftedge))
 		focusing = FALSE;
@@ -842,6 +838,8 @@ void read_file(FILE *f, int fd, const char *filename, bool undoable)
 
 	if (ISSET(MAKE_IT_UNIX))
 		openfile->fmt = NIX_FILE;
+	else if (openfile->fmt == UNSPECIFIED)
+		openfile->fmt = format;
 #endif
 }
 
@@ -1121,9 +1119,6 @@ void do_insertfile(bool execute)
 #ifdef ENABLE_MULTIBUFFER
 	bool was_multibuffer = ISSET(MULTIBUFFER);
 #endif
-#ifndef NANO_TINY
-	format_type was_fmt = openfile->fmt;
-#endif
 
 	/* Display newlines in filenames as ^J. */
 	as_an_at = FALSE;
@@ -1293,10 +1288,7 @@ void do_insertfile(bool execute)
 				if (openfile->current->lineno != was_current_lineno ||
 								openfile->current_x != was_current_x)
 					set_modified();
-#ifndef NANO_TINY
+
-				/* Ensure that the buffer retains the format that it had. */
-				openfile->fmt = was_fmt;
-#endif
 				refresh_needed = TRUE;
 			}