menu: Center boot menu

common/menu.c

@@ -495,12 +495,18 @@ char *config_entry_editor(const char *title, const char *orig_entry) {
 
 static size_t print_tree(size_t offset, size_t window, const char *shift, size_t level, size_t base_index, size_t selected_entry,
  struct menu_entry *current_entry,
- struct menu_entry **selected_menu_entry) {
+ struct menu_entry **selected_menu_entry,
+ size_t *max_len) {
  size_t max_entries = 0;
 
  bool no_print = false;
+ size_t dummy_max_len;
  if (shift == NULL) {
  no_print = true;
+ if (max_len == NULL) {
+ max_len = &dummy_max_len;
+ }
+ *max_len = 0;
  }
 
  for (;;) {
@@ -513,6 +519,7 @@ static size_t print_tree(size_t offset, size_t window, const char *shift, size_t
  goto skip_line;
  }
  if (!no_print) print("%s", shift);
+ size_t cur_len = strlen(shift);
  if (level) {
  for (size_t i = level - 1; i > 0; i--) {
  struct menu_entry *actual_parent = current_entry;
@@ -523,12 +530,14 @@ static size_t print_tree(size_t offset, size_t window, const char *shift, size_t
  } else {
  if (!no_print) print(" ");
  }
+ cur_len += 2;
  }
  if (current_entry->next == NULL) {
  if (!no_print) print(serial ? " `" : " └");
  } else {
  if (!no_print) print(serial ? " |" : " ├");
  }
+ cur_len += 2;
  }
  if (current_entry->sub) {
  if (!no_print) print(current_entry->expanded ? "[-]" : "[+]");
@@ -537,20 +546,26 @@ static size_t print_tree(size_t offset, size_t window, const char *shift, size_t
  } else {
  if (!no_print) print(" ");
  }
+ cur_len += 3;
  if (base_index + max_entries == selected_entry) {
  *selected_menu_entry = current_entry;
  if (!no_print) print("\e[7m");
  }
  if (!no_print) print(" %s \e[27m\n", current_entry->name);
+ cur_len += 1 + strlen(current_entry->name) + 1;
 skip_line:
  if (current_entry->sub && current_entry->expanded) {
  max_entries += print_tree(offset, window, shift, level + 1, base_index + max_entries + 1,
  selected_entry,
  current_entry->sub,
- selected_menu_entry);
+ selected_menu_entry,
+ max_len);
  }
  max_entries++;
  current_entry = current_entry->next;
+ if (cur_len > *max_len) {
+ *max_len = cur_len;
+ }
  }
  return max_entries;
 }
@@ -706,7 +721,7 @@ noreturn void _menu(bool first_run) {
  if (!skip_timeout && !timeout) {
  // Use print tree to load up selected_menu_entry and determine if the
  // default entry is valid.
- print_tree(0, 0, NULL, 0, 0, selected_entry, menu_tree, &selected_menu_entry);
+ print_tree(0, 0, NULL, 0, 0, selected_entry, menu_tree, &selected_menu_entry, NULL);
  if (selected_menu_entry == NULL || selected_menu_entry->sub != NULL) {
  quiet = false;
  print("Default entry is not valid or directory, booting to menu.\n");
@@ -794,8 +809,20 @@ noreturn void _menu(bool first_run) {
  set_cursor_pos_helper(x, y + 2);
  }
 
- size_t max_entries = print_tree(tree_offset, terms[0]->rows - 10, serial ? "| " : "│ ", 0, 0, selected_entry, menu_tree,
- &selected_menu_entry);
+ size_t max_tree_len;
+ print_tree(tree_offset, terms[0]->rows - 10, NULL, 0, 0, selected_entry, menu_tree,
+ &selected_menu_entry, &max_tree_len);
+
+ size_t tree_prefix_len = terms[0]->cols / 2 - max_tree_len / 2;
+ if (!serial) tree_prefix_len += strlen("│") - 1;
+ char *tree_prefix = ext_mem_alloc(tree_prefix_len);
+ memset(tree_prefix, ' ', tree_prefix_len);
+ memcpy(tree_prefix, serial ? "|" : "│", strlen(serial ? "|" : "│"));
+
+ size_t max_entries = print_tree(tree_offset, terms[0]->rows - 10, tree_prefix, 0, 0, selected_entry, menu_tree,
+ &selected_menu_entry, NULL);
+
+ pmm_free(tree_prefix, tree_prefix_len);
 
  {
  size_t x, y;
@@ -865,7 +892,7 @@ noreturn void _menu(bool first_run) {
  if (ent < (int)max_entries) {
  selected_entry = ent;
  print_tree(0, 0, NULL, 0, 0, selected_entry, menu_tree,
- &selected_menu_entry);
+ &selected_menu_entry, NULL);
  goto autoboot;
  }
  goto refresh;