text-progress-bar: Try to be more defensive about text leaks

We try to prevent text from showing through in the text splash,
by disable dmesg to screen and by redirecting console messages to
a log file.

Still, occasionally a kernel message may leak through.  This
commit tries to harden against that by moving the cursor up to
home when we aren't using it.

diff --git a/src/libply-splash-core/ply-text-display.c b/src/libply-splash-core/ply-text-display.c
index 7cabd98f4a67bfff41bfcf3e487053317f81458e..fcaff22ec309b04847261716eac69abceceaaaaa 100644 (file)
--- a/src/libply-splash-core/ply-text-display.c
+++ b/src/libply-splash-core/ply-text-display.c
@@ -58,6 +58,10 @@
 #define MOVE_CURSOR_SEQUENCE "\033[%d;%df"
 #endif
 
+#ifndef SET_TOP_AND_BOTTOM_MARGINS_SEQUENCE
+#define SET_TOP_AND_BOTTOM_MARGINS_SEQUENCE "\033[%d;%dr"
+#endif
+
 #ifndef HIDE_CURSOR_SEQUENCE
 #define HIDE_CURSOR_SEQUENCE "\033[?25l"
 #endif
@@ -70,6 +74,14 @@
 #define COLOR_SEQUENCE_FORMAT "\033[%dm"
 #endif
 
+#ifndef ENABLE_WRAPPING_SEQUENCE
+#define ENABLE_WRAPPING_SEQUENCE "\033[?7h"
+#endif
+
+#ifndef DISABLE_WRAPPING_SEQUENCE
+#define DISABLE_WRAPPING_SEQUENCE "\033[?7l"
+#endif
+
 #ifndef PAUSE_SEQUENCE
 #define PAUSE_SEQUENCE "\023"
 #endif
@@ -147,6 +159,37 @@ ply_text_display_set_cursor_position (ply_text_display_t *display,
                       row, column);
 }
 
+void
+ply_text_display_set_scrollable_area (ply_text_display_t *display,
+                                      int                 top_row,
+                                      int                 bottom_row)
+{
+  int number_of_rows;
+
+  number_of_rows = ply_text_display_get_number_of_rows (display);
+
+  top_row = CLAMP (top_row, 0, bottom_row);
+  bottom_row = CLAMP (bottom_row, top_row, number_of_rows - 1);
+
+  ply_terminal_write (display->terminal,
+                      SET_TOP_AND_BOTTOM_MARGINS_SEQUENCE,
+                      top_row, bottom_row);
+}
+
+void
+ply_text_display_enable_wrapping (ply_text_display_t *display)
+{
+  ply_terminal_write (display->terminal,
+                      ENABLE_WRAPPING_SEQUENCE);
+}
+
+void
+ply_text_display_disable_wrapping (ply_text_display_t *display)
+{
+  ply_terminal_write (display->terminal,
+                      DISABLE_WRAPPING_SEQUENCE);
+}
+
 void
 ply_text_display_clear_screen (ply_text_display_t *display)
 {

diff --git a/src/libply-splash-core/ply-text-display.h b/src/libply-splash-core/ply-text-display.h
index 3fd7dab23d5ccc107cc600e966106a59b74fed84..7f1e20b7f5bf25d898157c4c9369d599a5a62663 100644 (file)
--- a/src/libply-splash-core/ply-text-display.h
+++ b/src/libply-splash-core/ply-text-display.h
@@ -54,6 +54,12 @@ int  ply_text_display_get_number_of_columns (ply_text_display_t *display);
 void ply_text_display_set_cursor_position (ply_text_display_t *display,
                                            int                 column,
                                            int                 row);
+void ply_text_display_set_scrollable_area (ply_text_display_t *display,
+                                           int                 top_row,
+                                           int                 bottom_row);
+void ply_text_display_enable_wrapping (ply_text_display_t *display);
+void ply_text_display_disable_wrapping (ply_text_display_t *display);
+
 __attribute__((__format__ (__printf__, 2, 3)))
 void ply_text_display_write (ply_text_display_t *display,
                              const char         *format,

diff --git a/src/libply-splash-core/ply-text-progress-bar.c b/src/libply-splash-core/ply-text-progress-bar.c
index bf4b37810a94bff8d25e68a1cbbd58ca12156657..852f016b816e9639d5d694f8d66a6b31a672beb2 100644 (file)
--- a/src/libply-splash-core/ply-text-progress-bar.c
+++ b/src/libply-splash-core/ply-text-progress-bar.c
@@ -184,6 +184,8 @@ ply_text_progress_bar_draw (ply_text_progress_bar_t *progress_bar)
 
     width = progress_bar->number_of_columns - 2 - strlen (os_string);
 
+    ply_text_display_disable_wrapping (progress_bar->display);
+    ply_text_display_set_scrollable_area (progress_bar->display, 0, progress_bar->row);
     ply_text_display_set_cursor_position (progress_bar->display,
                                           progress_bar->column,
                                           progress_bar->row);
@@ -210,6 +212,7 @@ ply_text_progress_bar_draw (ply_text_progress_bar_t *progress_bar)
 
         ply_text_display_write (progress_bar->display, "%c", ' ');
     }
+    ply_text_display_set_cursor_position (progress_bar->display, 0, 0);
 
     ply_text_display_set_background_color (progress_bar->display,
                                            PLY_TERMINAL_COLOR_BLACK);
@@ -230,10 +233,18 @@ ply_text_progress_bar_draw (ply_text_progress_bar_t *progress_bar)
                                               progress_bar->row);
 
         ply_text_display_write (progress_bar->display, "%s", os_string);
+        ply_text_display_set_cursor_position (progress_bar->display, 0, 0);
 
         ply_text_display_set_foreground_color (progress_bar->display,
                                                PLY_TERMINAL_COLOR_DEFAULT);
     }
+
+    ply_text_display_set_background_color (progress_bar->display,
+                                           PLY_TERMINAL_COLOR_DEFAULT);
+
+    ply_text_display_set_scrollable_area (progress_bar->display, 0, progress_bar->row - 1);
+    ply_text_display_set_cursor_position (progress_bar->display, 0, 0);
+    ply_text_display_enable_wrapping (progress_bar->display);
 }
 
 void