aboutsummaryrefslogtreecommitdiff
path: root/readline/examples/rlptytest.c
blob: 9c42f8a2795385dc0ae49eb339264a72f77f8ead (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
/*
 *
 * Another test harness for the readline callback interface.
 *
 * Author: Bob Rossi <bob@brasko.net>
 */

#if defined (HAVE_CONFIG_H)
#include <config.h>
#endif

#include <stdio.h>
#include <sys/types.h>
#include <errno.h>
#include <curses.h>

#include <stdlib.h>
#include <unistd.h>

#include <signal.h>

#if 1	/* LINUX */
#include <pty.h>
#else
#include <util.h>
#endif

#ifdef READLINE_LIBRARY
#  include "readline.h"
#else
#  include <readline/readline.h>
#endif

/**
 * Master/Slave PTY used to keep readline off of stdin/stdout.
 */
static int masterfd = -1;
static int slavefd;

void
sigint (s)
     int s;
{
  tty_reset (STDIN_FILENO);
  close (masterfd);
  close (slavefd);
  printf ("\n");
  exit (0);
}

void
sigwinch (s)
     int s;
{
  rl_resize_terminal ();
}

static int 
user_input()
{
  int size;
  const int MAX = 1024;
  char *buf = (char *)malloc(MAX+1);

  size = read (STDIN_FILENO, buf, MAX);
  if (size == -1)
    return -1;

  size = write (masterfd, buf, size);
  if (size == -1)
    return -1;

  return 0;
}

static int 
readline_input()
{
  const int MAX = 1024;
  char *buf = (char *)malloc(MAX+1);
  int size;

  size = read (masterfd, buf, MAX);
  if (size == -1)
    {
      free( buf );
      buf = NULL;
      return -1;
    }

  buf[size] = 0;

  /* Display output from readline */
  if ( size > 0 )
    fprintf(stderr, "%s", buf);

  free( buf );
  buf = NULL;
  return 0;
}

static void 
rlctx_send_user_command(char *line)
{
  /* This happens when rl_callback_read_char gets EOF */
  if ( line == NULL )
    return;
    
  if (strcmp (line, "exit") == 0) {
  	tty_reset (STDIN_FILENO);
  	close (masterfd);
  	close (slavefd);
  	printf ("\n");
	exit (0);
  }
  
  /* Don't add the enter command */
  if ( line && *line != '\0' )
    add_history(line);
}

static void 
custom_deprep_term_function ()
{
}

static int 
init_readline (int inputfd, int outputfd) 
{
  FILE *inputFILE, *outputFILE;

  inputFILE = fdopen (inputfd, "r");
  if (!inputFILE)
    return -1;

  outputFILE = fdopen (outputfd, "w");
  if (!outputFILE)
    return -1;

  rl_instream = inputFILE;
  rl_outstream = outputFILE;

  /* Tell readline what the prompt is if it needs to put it back */
  rl_callback_handler_install("(rltest):  ", rlctx_send_user_command);

  /* Set the terminal type to dumb so the output of readline can be
   * understood by tgdb */
  if ( rl_reset_terminal("dumb") == -1 )
    return -1;

  /* For some reason, readline can not deprep the terminal.
   * However, it doesn't matter because no other application is working on
   * the terminal besides readline */
  rl_deprep_term_function = custom_deprep_term_function;

  using_history();
  read_history(".history"); 

  return 0;
}

static int 
main_loop(void)
{
  fd_set rset;
  int max;
    
  max = (masterfd > STDIN_FILENO) ? masterfd : STDIN_FILENO;
  max = (max > slavefd) ? max : slavefd;

  for (;;)
    {
      /* Reset the fd_set, and watch for input from GDB or stdin */
      FD_ZERO(&rset);
        
      FD_SET(STDIN_FILENO, &rset);
      FD_SET(slavefd, &rset);
      FD_SET(masterfd, &rset);

      /* Wait for input */
      if (select(max + 1, &rset, NULL, NULL, NULL) == -1)
        {
          if (errno == EINTR)
             continue;
          else
            return -1;
        }

      /* Input received through the pty:  Handle it 
       * Wrote to masterfd, slave fd has that input, alert readline to read it. 
       */
      if (FD_ISSET(slavefd, &rset))
        rl_callback_read_char();

      /* Input received through the pty.
       * Readline read from slavefd, and it wrote to the masterfd. 
       */
      if (FD_ISSET(masterfd, &rset))
        if ( readline_input() == -1 )
          return -1;

      /* Input received:  Handle it, write to masterfd (input to readline) */
      if (FD_ISSET(STDIN_FILENO, &rset))
        if ( user_input() == -1 )
          return -1;
  }

  return 0;
}

/* The terminal attributes before calling tty_cbreak */
static struct termios save_termios;
static struct winsize size;
static enum { RESET, TCBREAK } ttystate = RESET;

/* tty_cbreak: Sets terminal to cbreak mode. Also known as noncanonical mode.
 *    1. Signal handling is still turned on, so the user can still type those.
 *    2. echo is off
 *    3. Read in one char at a time.
 *
 * fd    - The file descriptor of the terminal
 * 
 * Returns: 0 on sucess, -1 on error
 */
int tty_cbreak(int fd){
   struct termios buf;
    int ttysavefd = -1;
   
   if(tcgetattr(fd, &save_termios) < 0)
      return -1;
      
   buf = save_termios;
   buf.c_lflag &= ~(ECHO | ICANON);
   buf.c_iflag &= ~(ICRNL | INLCR);
   buf.c_cc[VMIN] = 1;
   buf.c_cc[VTIME] = 0;

#if defined (VLNEXT) && defined (_POSIX_VDISABLE)
   buf.c_cc[VLNEXT] = _POSIX_VDISABLE;
#endif

#if defined (VDSUSP) && defined (_POSIX_VDISABLE)
   buf.c_cc[VDSUSP] = _POSIX_VDISABLE;
#endif

  /* enable flow control; only stty start char can restart output */
#if 0
  buf.c_iflag |= (IXON|IXOFF);
#ifdef IXANY
  buf.c_iflag &= ~IXANY;
#endif
#endif

  /* disable flow control; let ^S and ^Q through to pty */
  buf.c_iflag &= ~(IXON|IXOFF);
#ifdef IXANY
  buf.c_iflag &= ~IXANY;
#endif

  if(tcsetattr(fd, TCSAFLUSH, &buf) < 0)
      return -1;

   ttystate = TCBREAK;
   ttysavefd = fd;

   /* set size */
   if(ioctl(fd, TIOCGWINSZ, (char *)&size) < 0)
      return -1;

#ifdef DEBUG
   err_msg("%d rows and %d cols\n", size.ws_row, size.ws_col);   
#endif
   
   return (0);   
}

int 
tty_off_xon_xoff (int fd)
{
  struct termios buf;
  int ttysavefd = -1;

  if(tcgetattr(fd, &buf) < 0)
    return -1;
     
  buf.c_iflag &= ~(IXON|IXOFF);

  if(tcsetattr(fd, TCSAFLUSH, &buf) < 0)
    return -1;

  return 0;   
}

/* tty_reset: Sets the terminal attributes back to their previous state.
 * PRE: tty_cbreak must have already been called.
 * 
 * fd    - The file descrioptor of the terminal to reset.
 * 
 * Returns: 0 on success, -1 on error
 */
int tty_reset(int fd)
{
   if(ttystate != TCBREAK)
      return (0);

   if(tcsetattr(fd, TCSAFLUSH, &save_termios) < 0)
      return (-1);
      
   ttystate = RESET;
   
   return 0;   
}

int 
main()
{
  int val;
  val = openpty (&masterfd, &slavefd, NULL, NULL, NULL);
  if (val == -1)
    return -1;

  val = tty_off_xon_xoff (masterfd);
  if (val == -1)
    return -1;

  signal (SIGWINCH, sigwinch);
  signal (SIGINT, sigint);

  val = init_readline (slavefd, slavefd);
  if (val == -1)
    return -1;

  val = tty_cbreak (STDIN_FILENO);
  if (val == -1)
    return -1;

  val = main_loop ();

  tty_reset (STDIN_FILENO);

  if (val == -1)
    return -1;

  return 0;
}