src/x-list-font.c

   1 DEFUN ("x-list-fonts", Fx_list_fonts, Sx_list_fonts, 1, 5, 0,
   2   "Return a list of the names of available fonts matching PATTERN.\n\
   3 If optional arguments FACE and FRAME are specified, return only fonts\n\
   4 the same size as FACE on FRAME.\n\
   5 PATTERN is a string, perhaps with wildcard characters;\n\
   6   the * character matches any substring, and\n\
   7   the ? character matches any single character.\n\
   8   PATTERN is case-insensitive.\n\
   9 FACE is a face name--a symbol.\n\
  10 \n\
  11 The return value is a list of strings, suitable as arguments to\n\
  12 set-face-font.\n\
  13 \n\
  14 Fonts Emacs can't use (i.e. proportional fonts) may or may not be excluded\n\
  15 even if they match PATTERN and FACE.\n\
  16 The optional fourth argument MAXIMUM sets a limit on how many\n\
  17 fonts to match.  The first MAXIMUM fonts are reported.\n\
  18 The optional fifth argument WIDTH, if specified, is a number of columns\n\
  19 occupied by a character of a font.  In that case, return only fonts\n\
  20 the WIDTH times as wide as FACE on FRAME.")
  21   (pattern, face, frame, maximum, width)
  22     Lisp_Object pattern, face, frame, maximum, width;
  23 {
  24   FRAME_PTR f;
  25   int size, cols;
  26   int maxnames;
  27
  28   (*check_window_system_func) ();
  29   CHECK_STRING (pattern, 0);
  30   if (!NILP (face))
  31     CHECK_SYMBOL (face, 1);
  32
  33   if (NILP (maximum))
  34     maxnames = 2000;
  35   else
  36     {
  37       CHECK_NATNUM (maximum, 0);
  38       maxnames = XINT (maximum);
  39     }
  40
  41   if (!NILP (width))
  42     CHECK_NUMBER (width, 4);
  43
  44   /* We can't simply call check_x_frame because this function may be
  45      called before any frame is created.  */
  46   if (NILP (frame))
  47     f = selected_frame;
  48   else
  49     {
  50       CHECK_LIVE_FRAME (frame, 0);
  51       f = XFRAME (frame);
  52     }
  53   if (! FRAME_WINDOW_P (f))
  54     {
  55       /* Perhaps we have not yet created any frame.  */
  56       f = NULL;
  57       face = Qnil;
  58     }
  59
  60   /* Determine the width standard for comparison with the fonts we find.  */
  61
  62   if (NILP (face))
  63     size = 0;
  64   else
  65     {
  66       int face_id;
  67
  68       face_id = face_name_id_number (f, face);
  69
  70       if (face_id < 0 || face_id >= FRAME_N_PARAM_FACES (f)
  71           || FRAME_PARAM_FACES (f) [face_id] == 0
  72           || FRAME_PARAM_FACES (f) [face_id]->font == (XFontStruct *) (~0))
  73         size = FONT_WIDTH (FRAME_FONT (f));
  74       else
  75         size = FONT_WIDTH (FRAME_PARAM_FACES (f) [face_id]->font);
  76
  77       if (!NILP (width))
  78           size *= XINT (width);
  79     }
  80
  81   {
  82     Lisp_Object args[2];
  83
  84     args[0] = (*list_fonts_func) (f, pattern, size, maxnames);
  85     if (f == NULL)
  86       /* We don't have to check fontsets.  */
  87       return args[0];
  88     args[1] = list_fontsets (f, pattern, size);
  89     return Fnconc (2, args);
  90   }
  91 }