1/*
2 *
3 * Another test harness for the readline callback interface.
4 *
5 * Author: Bob Rossi <bob@brasko.net>
6 */
7
8#if defined (HAVE_CONFIG_H)
9#include <config.h>
10#endif
11
12#include <stdio.h>
13#include <sys/types.h>
14#include <errno.h>
15#include <curses.h>
16
17#include <stdlib.h>
18#include <unistd.h>
19
20#include <signal.h>
21
22#if 0	/* LINUX */
23#include <pty.h>
24#else
25#include <util.h>
26#endif
27
28#ifdef READLINE_LIBRARY
29#  include "readline.h"
30#else
31#  include <readline/readline.h>
32#endif
33
34/**
35 * Master/Slave PTY used to keep readline off of stdin/stdout.
36 */
37static int masterfd = -1;
38static int slavefd;
39
40void
41sigint (s)
42     int s;
43{
44  tty_reset (STDIN_FILENO);
45  close (masterfd);
46  close (slavefd);
47  printf ("\n");
48  exit (0);
49}
50
51static int
52user_input()
53{
54  int size;
55  const int MAX = 1024;
56  char *buf = (char *)malloc(MAX+1);
57
58  size = read (STDIN_FILENO, buf, MAX);
59  if (size == -1)
60    return -1;
61
62  size = write (masterfd, buf, size);
63  if (size == -1)
64    return -1;
65
66  return 0;
67}
68
69static int
70readline_input()
71{
72  const int MAX = 1024;
73  char *buf = (char *)malloc(MAX+1);
74  int size;
75
76  size = read (masterfd, buf, MAX);
77  if (size == -1)
78    {
79      free( buf );
80      buf = NULL;
81      return -1;
82    }
83
84  buf[size] = 0;
85
86  /* Display output from readline */
87  if ( size > 0 )
88    fprintf(stderr, "%s", buf);
89
90  free( buf );
91  buf = NULL;
92  return 0;
93}
94
95static void
96rlctx_send_user_command(char *line)
97{
98  /* This happens when rl_callback_read_char gets EOF */
99  if ( line == NULL )
100    return;
101
102  if (strcmp (line, "exit") == 0) {
103  	tty_reset (STDIN_FILENO);
104  	close (masterfd);
105  	close (slavefd);
106  	printf ("\n");
107	exit (0);
108  }
109
110  /* Don't add the enter command */
111  if ( line && *line != '\0' )
112    add_history(line);
113}
114
115static void
116custom_deprep_term_function ()
117{
118}
119
120static int
121init_readline (int inputfd, int outputfd)
122{
123  FILE *inputFILE, *outputFILE;
124
125  inputFILE = fdopen (inputfd, "r");
126  if (!inputFILE)
127    return -1;
128
129  outputFILE = fdopen (outputfd, "w");
130  if (!outputFILE)
131    return -1;
132
133  rl_instream = inputFILE;
134  rl_outstream = outputFILE;
135
136  /* Tell readline what the prompt is if it needs to put it back */
137  rl_callback_handler_install("(rltest):  ", rlctx_send_user_command);
138
139  /* Set the terminal type to dumb so the output of readline can be
140   * understood by tgdb */
141  if ( rl_reset_terminal("dumb") == -1 )
142    return -1;
143
144  /* For some reason, readline can not deprep the terminal.
145   * However, it doesn't matter because no other application is working on
146   * the terminal besides readline */
147  rl_deprep_term_function = custom_deprep_term_function;
148
149  using_history();
150  read_history(".history");
151
152  return 0;
153}
154
155static int
156main_loop(void)
157{
158  fd_set rset;
159  int max;
160
161  max = (masterfd > STDIN_FILENO) ? masterfd : STDIN_FILENO;
162  max = (max > slavefd) ? max : slavefd;
163
164  for (;;)
165    {
166      /* Reset the fd_set, and watch for input from GDB or stdin */
167      FD_ZERO(&rset);
168
169      FD_SET(STDIN_FILENO, &rset);
170      FD_SET(slavefd, &rset);
171      FD_SET(masterfd, &rset);
172
173      /* Wait for input */
174      if (select(max + 1, &rset, NULL, NULL, NULL) == -1)
175        {
176          if (errno == EINTR)
177             continue;
178          else
179            return -1;
180        }
181
182      /* Input received through the pty:  Handle it
183       * Wrote to masterfd, slave fd has that input, alert readline to read it.
184       */
185      if (FD_ISSET(slavefd, &rset))
186        rl_callback_read_char();
187
188      /* Input received through the pty.
189       * Readline read from slavefd, and it wrote to the masterfd.
190       */
191      if (FD_ISSET(masterfd, &rset))
192        if ( readline_input() == -1 )
193          return -1;
194
195      /* Input received:  Handle it, write to masterfd (input to readline) */
196      if (FD_ISSET(STDIN_FILENO, &rset))
197        if ( user_input() == -1 )
198          return -1;
199  }
200
201  return 0;
202}
203
204/* The terminal attributes before calling tty_cbreak */
205static struct termios save_termios;
206static struct winsize size;
207static enum { RESET, TCBREAK } ttystate = RESET;
208
209/* tty_cbreak: Sets terminal to cbreak mode. Also known as noncanonical mode.
210 *    1. Signal handling is still turned on, so the user can still type those.
211 *    2. echo is off
212 *    3. Read in one char at a time.
213 *
214 * fd    - The file descriptor of the terminal
215 *
216 * Returns: 0 on sucess, -1 on error
217 */
218int tty_cbreak(int fd){
219   struct termios buf;
220    int ttysavefd = -1;
221
222   if(tcgetattr(fd, &save_termios) < 0)
223      return -1;
224
225   buf = save_termios;
226   buf.c_lflag &= ~(ECHO | ICANON);
227   buf.c_iflag &= ~(ICRNL | INLCR);
228   buf.c_cc[VMIN] = 1;
229   buf.c_cc[VTIME] = 0;
230
231#if defined (VLNEXT) && defined (_POSIX_VDISABLE)
232   buf.c_cc[VLNEXT] = _POSIX_VDISABLE;
233#endif
234
235#if defined (VDSUSP) && defined (_POSIX_VDISABLE)
236   buf.c_cc[VDSUSP] = _POSIX_VDISABLE;
237#endif
238
239  /* enable flow control; only stty start char can restart output */
240#if 0
241  buf.c_iflag |= (IXON|IXOFF);
242#ifdef IXANY
243  buf.c_iflag &= ~IXANY;
244#endif
245#endif
246
247  /* disable flow control; let ^S and ^Q through to pty */
248  buf.c_iflag &= ~(IXON|IXOFF);
249#ifdef IXANY
250  buf.c_iflag &= ~IXANY;
251#endif
252
253  if(tcsetattr(fd, TCSAFLUSH, &buf) < 0)
254      return -1;
255
256   ttystate = TCBREAK;
257   ttysavefd = fd;
258
259   /* set size */
260   if(ioctl(fd, TIOCGWINSZ, (char *)&size) < 0)
261      return -1;
262
263#ifdef DEBUG
264   err_msg("%d rows and %d cols\n", size.ws_row, size.ws_col);
265#endif
266
267   return (0);
268}
269
270int
271tty_off_xon_xoff (int fd)
272{
273  struct termios buf;
274  int ttysavefd = -1;
275
276  if(tcgetattr(fd, &buf) < 0)
277    return -1;
278
279  buf.c_iflag &= ~(IXON|IXOFF);
280
281  if(tcsetattr(fd, TCSAFLUSH, &buf) < 0)
282    return -1;
283
284  return 0;
285}
286
287/* tty_reset: Sets the terminal attributes back to their previous state.
288 * PRE: tty_cbreak must have already been called.
289 *
290 * fd    - The file descrioptor of the terminal to reset.
291 *
292 * Returns: 0 on success, -1 on error
293 */
294int tty_reset(int fd)
295{
296   if(ttystate != TCBREAK)
297      return (0);
298
299   if(tcsetattr(fd, TCSAFLUSH, &save_termios) < 0)
300      return (-1);
301
302   ttystate = RESET;
303
304   return 0;
305}
306
307int
308main()
309{
310  int val;
311  val = openpty (&masterfd, &slavefd, NULL, NULL, NULL);
312  if (val == -1)
313    return -1;
314
315  val = tty_off_xon_xoff (masterfd);
316  if (val == -1)
317    return -1;
318
319  val = init_readline (slavefd, slavefd);
320  if (val == -1)
321    return -1;
322
323  val = tty_cbreak (STDIN_FILENO);
324  if (val == -1)
325    return -1;
326
327  signal (SIGINT, sigint);
328
329  val = main_loop ();
330
331  tty_reset (STDIN_FILENO);
332
333  if (val == -1)
334    return -1;
335
336  return 0;
337}
338