readline/readline/examples/rl-callbacktest.c

   1 /* Standard include files. stdio.h is required. */
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <string.h>
   5 #include <locale.h>
   6
   7 /* Used for select(2) */
   8 #include <sys/types.h>
   9 #include <sys/select.h>
  10
  11 #include <signal.h>
  12
  13 #include <errno.h>
  14 #include <stdio.h>
  15
  16 /* Standard readline include files. */
  17 #if defined (READLINE_LIBRARY)
  18 #  include "readline.h"
  19 #  include "history.h"
  20 #else
  21 #  include <readline/readline.h>
  22 #  include <readline/history.h>
  23 #endif
  24
  25 extern int errno;
  26
  27 static void cb_linehandler (char *);
  28 static void signandler (int);
  29
  30 int running, sigwinch_received;
  31 const char *prompt = "rltest$ ";
  32
  33 /* Handle SIGWINCH and window size changes when readline is not active and
  34    reading a character. */
  35 static void
  36 sighandler (int sig)
  37 {
  38   sigwinch_received = 1;
  39 }
  40
  41 /* Callback function called for each line when accept-line executed, EOF
  42    seen, or EOF character read.  This sets a flag and returns; it could
  43    also call exit(3). */
  44 static void
  45 cb_linehandler (char *line)
  46 {
  47   /* Can use ^D (stty eof) or `exit' to exit. */
  48   if (line == NULL || strcmp (line, "exit") == 0)
  49     {
  50       if (line == 0)
  51         printf ("\n");
  52       printf ("exit\n");
  53       /* This function needs to be called to reset the terminal settings,
  54          and calling it from the line handler keeps one extra prompt from
  55          being displayed. */
  56       rl_callback_handler_remove ();
  57
  58       running = 0;
  59     }
  60   else
  61     {
  62       if (*line)
  63         add_history (line);
  64       printf ("input line: %s\n", line);
  65       free (line);
  66     }
  67 }
  68
  69 int
  70 main (int c, char **v)
  71 {
  72   fd_set fds;
  73   int r;
  74
  75
  76   setlocale (LC_ALL, "");
  77
  78   /* Handle SIGWINCH */
  79   signal (SIGWINCH, sighandler);
  80
  81   /* Install the line handler. */
  82   rl_callback_handler_install (prompt, cb_linehandler);
  83
  84   /* Enter a simple event loop.  This waits until something is available
  85      to read on readline's input stream (defaults to standard input) and
  86      calls the builtin character read callback to read it.  It does not
  87      have to modify the user's terminal settings. */
  88   running = 1;
  89   while (running)
  90     {
  91       FD_ZERO (&fds);
  92       FD_SET (fileno (rl_instream), &fds);
  93
  94       r = select (FD_SETSIZE, &fds, NULL, NULL, NULL);
  95       if (r < 0 && errno != EINTR)
  96         {
  97           perror ("rltest: select");
  98           rl_callback_handler_remove ();
  99           break;
 100         }
 101       if (sigwinch_received)
 102         {
 103           rl_resize_terminal ();
 104           sigwinch_received = 0;
 105         }
 106       if (r < 0)
 107         continue;
 108
 109       if (FD_ISSET (fileno (rl_instream), &fds))
 110         rl_callback_read_char ();
 111     }
 112
 113   printf ("rltest: Event loop has exited\n");
 114   return 0;
 115 }