lib/readline/examples/manexamp.c

   1 /* manexamp.c -- The examples which appear in the documentation are here. */
   2
   3 #include <stdio.h>
   4 #include <readline/readline.h>
   5
   6 /* **************************************************************** */
   7 /*                                                                  */
   8 /*                      How to Emulate gets ()                      */
   9 /*                                                                  */
  10 /* **************************************************************** */
  11
  12 /* A static variable for holding the line. */
  13 static char *line_read = (char *)NULL;
  14
  15 /* Read a string, and return a pointer to it.  Returns NULL on EOF. */
  16 char *
  17 rl_gets ()
  18 {
  19   /* If the buffer has already been allocated, return the memory
  20      to the free pool. */
  21   if (line_read)
  22     {
  23       free (line_read);
  24       line_read = (char *)NULL;
  25     }
  26
  27   /* Get a line from the user. */
  28   line_read = readline ("");
  29
  30   /* If the line has any text in it, save it on the history. */
  31   if (line_read && *line_read)
  32     add_history (line_read);
  33
  34   return (line_read);
  35 }
  36
  37 /* **************************************************************** */
  38 /*                                                                  */
  39 /*        Writing a Function to be Called by Readline.              */
  40 /*                                                                  */
  41 /* **************************************************************** */
  42
  43 /* Invert the case of the COUNT following characters. */
  44 invert_case_line (count, key)
  45      int count, key;
  46 {
  47   register int start, end;
  48
  49   start = rl_point;
  50
  51   if (count < 0)
  52     {
  53       direction = -1;
  54       count = -count;
  55     }
  56   else
  57     direction = 1;
  58
  59   /* Find the end of the range to modify. */
  60   end = start + (count * direction);
  61
  62   /* Force it to be within range. */
  63   if (end > rl_end)
  64     end = rl_end;
  65   else if (end < 0)
  66     end = -1;
  67
  68   if (start > end)
  69     {
  70       int temp = start;
  71       start = end;
  72       end = temp;
  73     }
  74
  75   if (start == end)
  76     return;
  77
  78   /* Tell readline that we are modifying the line, so save the undo
  79      information. */
  80   rl_modifying (start, end);
  81
  82   for (; start != end; start += direction)
  83     {
  84       if (_rl_uppercase_p (rl_line_buffer[start]))
  85         rl_line_buffer[start] = _rl_to_lower (rl_line_buffer[start]);
  86       else if (_rl_lowercase_p (rl_line_buffer[start]))
  87         rl_line_buffer[start] = _rl_to_upper (rl_line_buffer[start]);
  88     }
  89
  90   /* Move point to on top of the last character changed. */
  91   rl_point = end - direction;
  92 }