guile-readline/readline.c

   1 /* readline.c --- line editing support for Guile */
   2
   3 /*      Copyright (C) 1997,1999 Free Software Foundation, Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software; see the file COPYING.  If not, write to
  17  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307 USA
  19  *
  20  */
  21
  22 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  23    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  24
  25 \f
  26
  27 #include "libguile/_scm.h"
  28 #if defined (HAVE_RL_GETC_FUNCTION)
  29 #include "libguile/libguile.h"
  30 #include "libguile/gh.h"
  31 #include "libguile/iselect.h"
  32
  33 #include <readline/readline.h>
  34 #include <readline/history.h>
  35 #include <sys/time.h>
  36
  37 #include "libguile/scm_validate.h"
  38 #include "readline.h"
  39
  40 scm_option scm_readline_opts[] = {
  41   { SCM_OPTION_BOOLEAN, "history-file", 1,
  42     "Use history file." },
  43   { SCM_OPTION_INTEGER, "history-length", 200,
  44     "History length." },
  45   { SCM_OPTION_INTEGER, "bounce-parens", 500,
  46     "Time (ms) to show matching opening parenthesis (0 = off)."}
  47 };
  48
  49 extern void stifle_history (int max);
  50
  51 SCM_DEFINE (scm_readline_options, "readline-options-interface", 0, 1, 0,
  52             (SCM setting),
  53 "")
  54 #define FUNC_NAME s_scm_readline_options
  55 {
  56   SCM ans = scm_options (setting,
  57                          scm_readline_opts,
  58                          SCM_N_READLINE_OPTIONS,
  59                          FUNC_NAME);
  60   stifle_history (SCM_HISTORY_LENGTH);
  61   return ans;
  62 }
  63 #undef FUNC_NAME
  64
  65 #ifndef HAVE_STRDUP
  66 static char *
  67 strdup (char *s)
  68 {
  69   int len = strlen (s);
  70   char *new = malloc (len + 1);
  71   strcpy (new, s);
  72   return new;
  73 }
  74 #endif /* HAVE_STRDUP */
  75
  76 #ifndef HAVE_RL_CLEANUP_AFTER_SIGNAL
  77
  78 /* These are readline functions added in release 2.3.  They will work
  79  * together with readline-2.1 and 2.2.  (The readline interface is
  80  * disabled for earlier releases.)
  81  * They are declared static; if we want to use them elsewhere, then
  82  * we need external declarations for them, but at the moment, I don't
  83  * think anything else in Guile ought to use these.
  84  */
  85
  86 extern void _rl_clean_up_for_exit ();
  87 extern void _rl_kill_kbd_macro ();
  88 extern int _rl_init_argument ();
  89
  90 void
  91 rl_cleanup_after_signal ()
  92 {
  93 #ifdef HAVE_RL_CLEAR_SIGNALS
  94   _rl_clean_up_for_exit ();
  95 #endif
  96   (*rl_deprep_term_function) ();
  97 #ifdef HAVE_RL_CLEAR_SIGNALS
  98   rl_clear_signals ();
  99 #endif
 100   rl_pending_input = 0;
 101 }
 102
 103 void
 104 rl_free_line_state ()
 105 {
 106   register HIST_ENTRY *entry;
 107
 108   free_undo_list ();
 109
 110   entry = current_history ();
 111   if (entry)
 112     entry->data = (char *)NULL;
 113
 114   _rl_kill_kbd_macro ();
 115   rl_clear_message ();
 116   _rl_init_argument ();
 117 }
 118
 119 #endif /* !HAVE_RL_CLEANUP_AFTER_SIGNAL */
 120
 121 static int promptp;
 122 static SCM input_port;
 123 static SCM before_read;
 124
 125 static int
 126 current_input_getc (FILE *in)
 127 {
 128   SCM ans;
 129   if (promptp && SCM_NIMP (before_read))
 130     {
 131       scm_apply (before_read, SCM_EOL, SCM_EOL);
 132       promptp = 0;
 133     }
 134   ans = scm_getc (input_port);
 135   return ans;
 136 }
 137
 138 static void
 139 redisplay ()
 140 {
 141   rl_redisplay ();
 142   /* promptp = 1; */
 143 }
 144
 145 static int in_readline = 0;
 146 #ifdef USE_THREADS
 147 static scm_mutex_t reentry_barrier_mutex;
 148 #endif
 149
 150 static SCM internal_readline (SCM text);
 151 static SCM handle_error (void *data, SCM tag, SCM args);
 152 static void reentry_barrier ();
 153
 154
 155 SCM_DEFINE (scm_readline, "%readline", 0, 4, 0,
 156             (SCM text, SCM inp, SCM outp, SCM read_hook),
 157 "")
 158 #define FUNC_NAME s_scm_readline
 159 {
 160   SCM ans;
 161
 162   reentry_barrier ();
 163
 164   before_read = SCM_BOOL_F;
 165
 166   if (!SCM_UNBNDP (text))
 167     {
 168       if (!(SCM_NIMP (text) && SCM_STRINGP (text)))
 169         {
 170           --in_readline;
 171           scm_wrong_type_arg (s_scm_readline, SCM_ARG1, text);
 172         }
 173       SCM_COERCE_SUBSTR (text);
 174     }
 175
 176   if (!((SCM_UNBNDP (inp) && SCM_NIMP (scm_cur_inp) && SCM_OPINFPORTP (inp))
 177         || SCM_NIMP (inp) && SCM_OPINFPORTP (inp)))
 178     {
 179       --in_readline;
 180       scm_misc_error (s_scm_readline,
 181                       "Input port is not open or not a file port",
 182                       SCM_EOL);
 183     }
 184
 185   if (!((SCM_UNBNDP (outp) && SCM_NIMP (scm_cur_outp) && SCM_OPINFPORTP (outp))
 186         || (SCM_NIMP (outp) && SCM_OPOUTFPORTP (outp))))
 187     {
 188       --in_readline;
 189       scm_misc_error (s_scm_readline,
 190                       "Output port is not open or not a file port",
 191                       SCM_EOL);
 192     }
 193
 194   if (!(SCM_UNBNDP (read_hook) || SCM_FALSEP (read_hook)))
 195     {
 196       if (!(SCM_NFALSEP (scm_thunk_p (read_hook))))
 197         {
 198           --in_readline;
 199           scm_wrong_type_arg (s_scm_readline, SCM_ARG4, read_hook);
 200         }
 201       before_read = read_hook;
 202     }
 203
 204   scm_readline_init_ports (inp, outp);
 205
 206   ans = scm_internal_catch (SCM_BOOL_T,
 207                             (scm_catch_body_t) internal_readline,
 208                             (void *) text,
 209                             handle_error, 0);
 210
 211   fclose (rl_instream);
 212   fclose (rl_outstream);
 213
 214   --in_readline;
 215   return ans;
 216 }
 217 #undef FUNC_NAME
 218
 219
 220 static void
 221 reentry_barrier ()
 222 {
 223   int reentryp = 0;
 224 #ifdef USE_THREADS
 225   /* We should rather use scm_mutex_try_lock when it becomes available */
 226   scm_mutex_lock (&reentry_barrier_mutex);
 227 #endif
 228   if (in_readline)
 229     reentryp = 1;
 230   else
 231     ++in_readline;
 232 #ifdef USE_THREADS
 233   scm_mutex_unlock (&reentry_barrier_mutex);
 234 #endif
 235   if (reentryp)
 236     scm_misc_error (s_scm_readline, "readline is not reentrant", SCM_EOL);
 237 }
 238
 239 static SCM
 240 handle_error (void *data, SCM tag, SCM args)
 241 {
 242   rl_free_line_state ();
 243   rl_cleanup_after_signal ();
 244   fputc ('\n', rl_outstream); /* We don't want next output on this line */
 245   fclose (rl_instream);
 246   fclose (rl_outstream);
 247   --in_readline;
 248   scm_handle_by_throw (data, tag, args);
 249   return SCM_UNSPECIFIED; /* never reached */
 250 }
 251
 252 static SCM
 253 internal_readline (SCM text)
 254 {
 255   SCM ret;
 256   char *s;
 257   char *prompt = SCM_UNBNDP (text) ? "" : SCM_CHARS (text);
 258
 259   promptp = 1;
 260   s = readline (prompt);
 261   if (s)
 262     ret = scm_makfrom0str (s);
 263   else
 264     ret = SCM_EOF_VAL;
 265
 266   free (s);
 267
 268   return ret;
 269 }
 270
 271 static FILE *
 272 stream_from_fport (SCM port, char *mode, const char *subr)
 273 {
 274   int fd;
 275   FILE *f;
 276
 277   fd = dup (((struct scm_fport *) SCM_STREAM (port))->fdes);
 278   if (fd == -1)
 279     {
 280       --in_readline;
 281       scm_syserror (subr);
 282     }
 283
 284   f = fdopen (fd, mode);
 285   if (f == NULL)
 286     {
 287       --in_readline;
 288       scm_syserror (subr);
 289     }
 290
 291   return f;
 292 }
 293
 294 void
 295 scm_readline_init_ports (SCM inp, SCM outp)
 296 {
 297   if (SCM_UNBNDP (inp))
 298     inp = scm_cur_inp;
 299
 300   if (SCM_UNBNDP (outp))
 301     outp = scm_cur_outp;
 302
 303   if (!(SCM_NIMP (inp) && SCM_OPINFPORTP (inp))) {
 304     scm_misc_error (0,
 305                     "Input port is not open or not a file port",
 306                     SCM_EOL);
 307   }
 308
 309   if (!(SCM_NIMP (outp) && SCM_OPOUTFPORTP (outp))) {
 310     scm_misc_error (0,
 311                     "Output port is not open or not a file port",
 312                     SCM_EOL);
 313   }
 314
 315   input_port = inp;
 316   rl_instream = stream_from_fport (inp, "r", s_scm_readline);
 317   rl_outstream = stream_from_fport (outp, "w", s_scm_readline);
 318 }
 319
 320
 321
 322 SCM_DEFINE (scm_add_history, "add-history", 1, 0, 0,
 323             (SCM text),
 324 "")
 325 #define FUNC_NAME s_scm_add_history
 326 {
 327   char* s;
 328   SCM_VALIDATE_STRING (1,text);
 329   SCM_COERCE_SUBSTR (text);
 330
 331   s = SCM_CHARS (text);
 332   add_history (strdup (s));
 333
 334   return SCM_UNSPECIFIED;
 335 }
 336 #undef FUNC_NAME
 337
 338
 339 SCM_DEFINE (scm_read_history, "read-history", 1, 0, 0,
 340             (SCM file),
 341 "")
 342 #define FUNC_NAME s_scm_read_history
 343 {
 344   SCM_VALIDATE_STRING (1,file);
 345   return SCM_NEGATE_BOOL(read_history (SCM_ROCHARS (file)));
 346 }
 347 #undef FUNC_NAME
 348
 349
 350 SCM_DEFINE (scm_write_history, "write-history", 1, 0, 0,
 351             (SCM file),
 352 "")
 353 #define FUNC_NAME s_scm_write_history
 354 {
 355   SCM_VALIDATE_STRING (1,file);
 356   return SCM_NEGATE_BOOL(write_history (SCM_ROCHARS (file)));
 357 }
 358 #undef FUNC_NAME
 359
 360
 361 SCM_DEFINE (scm_filename_completion_function, "filename-completion-function", 2, 0, 0,
 362             (SCM text, SCM continuep),
 363 "")
 364 #define FUNC_NAME s_scm_filename_completion_function
 365 {
 366   char *s;
 367   SCM ans;
 368   SCM_VALIDATE_STRING (1,text);
 369   SCM_COERCE_SUBSTR (text);
 370   s = filename_completion_function (SCM_CHARS (text), SCM_NFALSEP (continuep));
 371   ans = scm_makfrom0str (s);
 372   free (s);
 373   return ans;
 374 }
 375 #undef FUNC_NAME
 376
 377 /*
 378  * The following has been modified from code contributed by
 379  * Andrew Archibald <aarchiba@undergrad.math.uwaterloo.ca>
 380  */
 381
 382 SCM scm_readline_completion_function_var;
 383
 384 static char *
 385 completion_function (char *text, int continuep)
 386 {
 387   SCM compfunc = SCM_CDR (scm_readline_completion_function_var);
 388   SCM res;
 389
 390   if (SCM_FALSEP (compfunc))
 391     return NULL; /* #f => completion disabled */
 392   else
 393     {
 394       SCM t = scm_makfrom0str (text);
 395       SCM c = continuep ? SCM_BOOL_T : SCM_BOOL_F;
 396       res = scm_apply (compfunc, SCM_LIST2 (t, c), SCM_EOL);
 397
 398       if (SCM_FALSEP (res))
 399         return NULL;
 400
 401       if (!(SCM_NIMP (res) && SCM_STRINGP (res)))
 402         scm_misc_error (s_scm_readline,
 403                         "Completion function returned bogus value: %S",
 404                         SCM_LIST1 (res));
 405       SCM_COERCE_SUBSTR (res);
 406       return strdup (SCM_CHARS (res));
 407     }
 408 }
 409
 410 /*Bouncing parenthesis (reimplemented by GH, 11/23/98, since readline is strict gpl)*/
 411
 412 static void match_paren(int x, int k);
 413 static int find_matching_paren(int k);
 414 static void init_bouncing_parens();
 415
 416 static void
 417 init_bouncing_parens()
 418 {
 419   if(strncmp(rl_get_keymap_name(rl_get_keymap()), "vi", 2)) {
 420     rl_bind_key(')', match_paren);
 421     rl_bind_key(']', match_paren);
 422     rl_bind_key('}', match_paren);
 423   }
 424 }
 425
 426 static int
 427 find_matching_paren(int k)
 428 {
 429   register int i;
 430   register char c = 0;
 431   int end_parens_found = 0;
 432
 433   /* Choose the corresponding opening bracket.  */
 434   if (k == ')') c = '(';
 435   else if (k == ']') c = '[';
 436   else if (k == '}') c = '{';
 437
 438   for (i=rl_point-2; i>=0; i--)
 439     {
 440       /* Is the current character part of a character literal?  */
 441       if (i - 2 >= 0
 442           && rl_line_buffer[i - 1] == '\\'
 443           && rl_line_buffer[i - 2] == '#')
 444         ;
 445       else if (rl_line_buffer[i] == k)
 446         end_parens_found++;
 447       else if (rl_line_buffer[i] == '"')
 448         {
 449           /* Skip over a string literal.  */
 450           for (i--; i >= 0; i--)
 451             if (rl_line_buffer[i] == '"'
 452                 && ! (i - 1 >= 0
 453                       && rl_line_buffer[i - 1] == '\\'))
 454               break;
 455         }
 456       else if (rl_line_buffer[i] == c)
 457         {
 458           if (end_parens_found==0) return i;
 459           else --end_parens_found;
 460         }
 461     }
 462   return -1;
 463 }
 464
 465 static void
 466 match_paren(int x, int k)
 467 {
 468   int tmp;
 469   fd_set readset;
 470   struct timeval timeout;
 471
 472   rl_insert(x, k);
 473   if (!SCM_READLINE_BOUNCE_PARENS)
 474     return;
 475
 476   /* Did we just insert a quoted paren?  If so, then don't bounce.  */
 477   if (rl_point - 1 >= 1
 478       && rl_line_buffer[rl_point - 2] == '\\')
 479     return;
 480
 481   tmp = 1000 * SCM_READLINE_BOUNCE_PARENS;
 482   timeout.tv_sec = tmp / 1000000;
 483   timeout.tv_usec = tmp % 1000000;
 484   FD_ZERO(&readset);
 485   FD_SET(fileno(rl_instream), &readset);
 486
 487   if(rl_point > 1) {
 488     tmp = rl_point;
 489     rl_point = find_matching_paren(k);
 490     if(rl_point > -1) {
 491       rl_redisplay();
 492       scm_internal_select(1, &readset, NULL, NULL, &timeout);
 493     }
 494     rl_point = tmp;
 495   }
 496 }
 497
 498
 499 void
 500 scm_init_readline ()
 501 {
 502 #include "readline.x"
 503   scm_readline_completion_function_var
 504     = scm_sysintern ("*readline-completion-function*", SCM_BOOL_F);
 505   rl_getc_function = current_input_getc;
 506   rl_redisplay_function = redisplay;
 507   rl_completion_entry_function = (Function*) completion_function;
 508   rl_basic_word_break_characters = "\t\n\"'`;()";
 509   rl_readline_name = "Guile";
 510
 511 #ifdef USE_THREADS
 512   scm_mutex_init (&reentry_barrier_mutex);
 513 #endif
 514   scm_init_opts (scm_readline_options,
 515                  scm_readline_opts,
 516                  SCM_N_READLINE_OPTIONS);
 517   init_bouncing_parens();
 518   scm_add_feature ("readline");
 519 }
 520
 521 #endif