Handle \e[J and \e[H so we can clear the terminal.

diff --git a/terminal.c b/terminal.c
index 923539e..82227e3 100644 (file)
--- a/terminal.c
+++ b/terminal.c
@@ -60,6 +60,8 @@ struct terminal {
        struct buffer *buffer;
        GIOChannel *channel;
        uint32_t modifiers;
+       char escape[64];
+       int escape_length;
        int state;
 };
 
@@ -70,7 +72,7 @@ terminal_draw_contents(struct terminal *terminal)
        cairo_surface_t *surface;
        cairo_t *cr;
        cairo_font_extents_t extents;
-       int i, line;
+       int i, row;
 
        window_get_child_rectangle(terminal->window, &rectangle);
 
@@ -89,10 +91,10 @@ terminal_draw_contents(struct terminal *terminal)
        cairo_set_font_size(cr, 14);
 
        cairo_font_extents(cr, &extents);
-       for (i = 0; i < terminal->height; i++) {
-               line = (terminal->tail + i) % terminal->height;
+       for (i = 0; i < terminal->total_rows; i++) {
+               row = (terminal->tail + i) % terminal->height;
                cairo_move_to(cr, 0, extents.ascent + extents.height * i);
-               cairo_show_text(cr, &terminal->data[line * (terminal->width + 1)]);
+               cairo_show_text(cr, &terminal->data[row * (terminal->width + 1)]);
        }
        cairo_destroy(cr);
 
@@ -123,7 +125,10 @@ idle_redraw(void *data)
 }
 
 #define STATE_NORMAL 0
-#define STATE_SKIP_TO_ALPHA 1
+#define STATE_ESCAPE 1
+
+static void
+terminal_data(struct terminal *terminal, const char *data, size_t length);
 
 static void
 terminal_schedule_redraw(struct terminal *terminal)
@@ -137,6 +142,32 @@ terminal_schedule_redraw(struct terminal *terminal)
 }
 
 static void
+handle_escape(struct terminal *terminal)
+{
+       char *row;
+       int i, j;
+
+       terminal->escape[terminal->escape_length++] = '\0';
+       if (strcmp(terminal->escape, "\e[J") == 0) {
+               row = &terminal->data[terminal->row * (terminal->width + 1)];
+               memset(&row[terminal->column], 0, terminal->width - terminal->column);
+               for (i = terminal->total_rows; i < terminal->height; i++) {
+
+                       j = terminal->row + i;
+                       if (j >= terminal->height)
+                               j -= terminal->height;
+                       
+                       row = &terminal->data[j * (terminal->width + 1)];
+                       memset(row, 0, terminal->width);
+               }
+       } else if (strcmp(terminal->escape, "\e[H") == 0) {
+               terminal->row = terminal->tail;
+               terminal->total_rows = 1;
+               terminal->column = 0;
+       }
+}
+
+static void
 terminal_data(struct terminal *terminal, const char *data, size_t length)
 {
        int i;
@@ -145,27 +176,39 @@ terminal_data(struct terminal *terminal, const char *data, size_t length)
        for (i = 0; i < length; i++) {
                row = &terminal->data[terminal->row * (terminal->width + 1)];
 
-               if (terminal->state == STATE_SKIP_TO_ALPHA) {
-                       if (isalpha(data[i]))
+               if (terminal->state == STATE_ESCAPE) {
+                       terminal->escape[terminal->escape_length++] = data[i];
+                       if (terminal->escape_length == 2 && data[i] != '[') {
+                               /* Bad escape sequence. */
+                               terminal->state = STATE_NORMAL;
+                               goto cancel_escape;
+                       }
+
+                       if (isalpha(data[i])) {
                                terminal->state = STATE_NORMAL;
+                               handle_escape(terminal);
+                       } 
                        continue;
                }
 
+       cancel_escape:
                switch (data[i]) {
                case '\r':
                        terminal->column = 0;
                        break;
                case '\n':
-                       terminal->row++;
-                       terminal->total_rows++;
                        terminal->column = 0;
+                       terminal->row++;
                        if (terminal->row == terminal->height)
                                terminal->row = 0;
-                       if (terminal->row == terminal->tail && terminal->total_rows > 0) {
+                       if (terminal->total_rows == terminal->height) {
                                memset(&terminal->data[terminal->row * (terminal->width + 1)],
                                       0, terminal->width);
                                terminal->tail++;
+                       } else {
+                               terminal->total_rows++;
                        }
+
                        if (terminal->tail == terminal->height)
                                terminal->tail = 0;
                        break;
@@ -174,7 +217,9 @@ terminal_data(struct terminal *terminal, const char *data, size_t length)
                        terminal->column = (terminal->column + 7) & ~7;
                        break;
                case '\e':
-                       terminal->state = STATE_SKIP_TO_ALPHA;
+                       terminal->state = STATE_ESCAPE;
+                       terminal->escape[0] = '\e';
+                       terminal->escape_length = 1;
                        break;
                default:
                        if (terminal->column < terminal->width)
@@ -337,6 +382,7 @@ terminal_create(struct wl_display *display, int fd)
        terminal->redraw_scheduled = 1;
        terminal->width = 80;
        terminal->height = 25;
+       terminal->total_rows = 1;
        size = (terminal->width + 1) * terminal->height;
        terminal->data = malloc(size);
        memset(terminal->data, 0, size);