console: do not fill buffer if not required

We allow NULL lines in the buffer so we no longer have to create empty
lines when writing anywhere in the buffer.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>

diff --git a/src/console_cell.c b/src/console_cell.c
index 1cbe0d7..1ea0b53 100644 (file)
--- a/src/console_cell.c
+++ b/src/console_cell.c
@@ -568,19 +568,18 @@ void kmscon_buffer_write(struct kmscon_buffer *buf, unsigned int x,
                return;
        }
 
-       if (!buf->current[y]) {
-               while (buf->fill <= y) {
-                       ret = new_line(&line);
-                       if (ret) {
-                               log_warn("console: cannot allocate line "
-                                               "(%d); dropping input\n", ret);
-                               return;
-                       }
-                       buf->current[buf->fill] = line;
-                       buf->fill++;
+       line = buf->current[y];
+       if (!line) {
+               ret = new_line(&line);
+               if (ret) {
+                       log_warn("console: cannot allocate line (%d); dropping input\n", ret);
+                       return;
                }
+
+               buf->current[y] = line;
+               if (buf->fill <= y)
+                       buf->fill = y + 1;
        }
-       line = buf->current[y];
 
        if (x >= line->size) {
                ret = resize_line(line, buf->size_x);
@@ -619,7 +618,7 @@ kmscon_symbol_t kmscon_buffer_read(struct kmscon_buffer *buf, unsigned int x,
 
 void kmscon_buffer_newline(struct kmscon_buffer *buf)
 {
-       struct line *line, *nl;
+       struct line *nl;
        int ret;
 
        if (!buf)
@@ -633,11 +632,7 @@ void kmscon_buffer_newline(struct kmscon_buffer *buf)
        }
 
        if (buf->fill >= buf->size_y) {
-               line = buf->current[0];
-               if (!line)
-                       return;
-
-               link_to_scrollback(buf, line);
+               link_to_scrollback(buf, buf->current[0]);
                memmove(buf->current, &buf->current[1],
                                (buf->size_y - 1) * sizeof(struct line*));
                buf->current[buf->size_y - 1] = NULL;