readline/examples/rlptytest.c

   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  */
  37 static int masterfd = -1;
  38 static int slavefd;
  39
  40 void
  41 sigint (s)
  42      int s;
  43 {
  44   tty_reset (STDIN_FILENO);
  45   close (masterfd);
  46   close (slavefd);
  47   printf ("\n");
  48   exit (0);
  49 }
  50
  51 static int
  52 user_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
  69 static int
  70 readline_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
  95 static void
  96 rlctx_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
 115 static void
 116 custom_deprep_term_function ()
 117 {
 118 }
 119
 120 static int
 121 init_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
 155 static int
 156 main_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 */
 205 static struct termios save_termios;
 206 static struct winsize size;
 207 static 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  */
 218 int 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
 270 int
 271 tty_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  */
 294 int 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
 307 int
 308 main()
 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 }