shell/cmdedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Termios command line History and Editting, originally
   4  * intended for NetBSD sh (ash)
   5  * Copyright (c) 1999
   6  *      Main code:            Adam Rogoyski <rogoyski@cs.utexas.edu>
   7  *      Etc:                  Dave Cinege <dcinege@psychosis.com>
   8  *  Majorly adjusted/re-written for busybox:
   9  *                            Erik Andersen <andersee@debian.org>
  10  *
  11  * You may use this code as you wish, so long as the original author(s)
  12  * are attributed in any redistributions of the source code.
  13  * This code is 'as is' with no warranty.
  14  * This code may safely be consumed by a BSD or GPL license.
  15  *
  16  * v 0.5  19990328      Initial release
  17  *
  18  * Future plans: Simple file and path name completion. (like BASH)
  19  *
  20  */
  21
  22 /*
  23    Usage and Known bugs:
  24    Terminal key codes are not extensive, and more will probably
  25    need to be added. This version was created on Debian GNU/Linux 2.x.
  26    Delete, Backspace, Home, End, and the arrow keys were tested
  27    to work in an Xterm and console. Ctrl-A also works as Home.
  28    Ctrl-E also works as End. The binary size increase is <3K.
  29
  30    Editting will not display correctly for lines greater then the
  31    terminal width. (more then one line.) However, history will.
  32  */
  33
  34 #include "internal.h"
  35 #ifdef BB_FEATURE_SH_COMMAND_EDITING
  36
  37 #include <stdio.h>
  38 #include <errno.h>
  39 #include <unistd.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <sys/ioctl.h>
  43 #include <ctype.h>
  44 #include <signal.h>
  45
  46
  47 #define  MAX_HISTORY   15               /* Maximum length of the linked list for the command line history */
  48
  49 #define ESC     27
  50 #define DEL     127
  51 #define member(c, s) ((c) ? ((char *)strchr ((s), (c)) != (char *)NULL) : 0)
  52 #define whitespace(c) (((c) == ' ') || ((c) == '\t'))
  53
  54 static struct history *his_front = NULL;        /* First element in command line list */
  55 static struct history *his_end = NULL;  /* Last element in command line list */
  56
  57 /* ED: sparc termios is broken: revert back to old termio handling. */
  58 #ifdef BB_FEATURE_USE_TERMIOS
  59
  60 #if #cpu(sparc)
  61 #      include <termio.h>
  62 #      define termios termio
  63 #      define setTermSettings(fd,argp) ioctl(fd,TCSETAF,argp)
  64 #      define getTermSettings(fd,argp) ioctl(fd,TCGETA,argp)
  65 #else
  66 #      include <termios.h>
  67 #      define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
  68 #      define getTermSettings(fd,argp) tcgetattr(fd, argp);
  69 #endif
  70
  71 /* Current termio and the previous termio before starting sh */
  72 struct termios initial_settings, new_settings;
  73
  74
  75 #ifndef _POSIX_VDISABLE
  76 #define _POSIX_VDISABLE '\0'
  77 #endif
  78
  79 #endif
  80
  81
  82
  83 static int cmdedit_termw = 80;  /* actual terminal width */
  84 static int cmdedit_scroll = 27; /* width of EOL scrolling region */
  85 static int history_counter = 0; /* Number of commands in history list */
  86 static int reset_term = 0;              /* Set to true if the terminal needs to be reset upon exit */
  87 static int exithandler_set = 0; /* Set to true when atexit() has been called */
  88
  89 struct history {
  90         char *s;
  91         struct history *p;
  92         struct history *n;
  93 };
  94
  95 #define xwrite write
  96
  97 /*
  98  * TODO: Someday we want to implement 'horizontal scrolling' of the
  99  * command-line when the user has typed more than the current width. This
 100  * would allow the user to see a 'window' of what he has typed.
 101  */
 102 void
 103 cmdedit_setwidth(int w)
 104 {
 105         if (w > 20) {
 106                 cmdedit_termw = w;
 107                 cmdedit_scroll = w / 3;
 108         } else {
 109                 errorMsg("\n*** Error: minimum screen width is 21\n");
 110         }
 111 }
 112
 113
 114 void cmdedit_reset_term(void)
 115 {
 116         if (reset_term)
 117                 /* sparc and other have broken termios support: use old termio handling. */
 118                 setTermSettings(fileno(stdin), (void*) &initial_settings);
 119 #ifdef BB_FEATURE_CLEAN_UP
 120         if (his_front) {
 121                 struct history *n;
 122                 //while(his_front!=his_end) {
 123                 while(his_front!=his_end) {
 124                         n = his_front->n;
 125                         free(his_front->s);
 126                         free(his_front);
 127                         his_front=n;
 128                 }
 129         }
 130 #endif
 131 }
 132
 133 void clean_up_and_die(int sig)
 134 {
 135         cmdedit_reset_term();
 136         fprintf(stdout, "\n");
 137         if (sig!=SIGINT)
 138                 exit(TRUE);
 139 }
 140
 141 /* Go to HOME position */
 142 void input_home(int outputFd, int *cursor)
 143 {
 144         while (*cursor > 0) {
 145                 xwrite(outputFd, "\b", 1);
 146                 --*cursor;
 147         }
 148 }
 149
 150 /* Go to END position */
 151 void input_end(int outputFd, int *cursor, int len)
 152 {
 153         while (*cursor < len) {
 154                 xwrite(outputFd, "\033[C", 3);
 155                 ++*cursor;
 156         }
 157 }
 158
 159 /* Delete the char in back of the cursor */
 160 void input_backspace(char* command, int outputFd, int *cursor, int *len)
 161 {
 162         int j = 0;
 163
 164 /* Debug crap */
 165 //fprintf(stderr, "\nerik: len=%d, cursor=%d, strlen(command)='%d'\n", *len, *cursor, strlen(command));
 166 //xwrite(outputFd, command, *len);
 167 //*cursor = *len;
 168
 169
 170         if (*cursor > 0) {
 171                 xwrite(outputFd, "\b \b", 3);
 172                 --*cursor;
 173                 memmove(command + *cursor, command + *cursor + 1,
 174                                 BUFSIZ - *cursor + 1);
 175
 176                 for (j = *cursor; j < (BUFSIZ - 1); j++) {
 177                         if (!*(command + j))
 178                                 break;
 179                         else
 180                                 xwrite(outputFd, (command + j), 1);
 181                 }
 182
 183                 xwrite(outputFd, " \b", 2);
 184
 185                 while (j-- > *cursor)
 186                         xwrite(outputFd, "\b", 1);
 187
 188                 --*len;
 189         }
 190 }
 191
 192 /* Delete the char in front of the cursor */
 193 void input_delete(char* command, int outputFd, int cursor, int *len)
 194 {
 195         int j = 0;
 196
 197         if (cursor == *len)
 198                 return;
 199
 200         memmove(command + cursor, command + cursor + 1,
 201                         BUFSIZ - cursor - 1);
 202         for (j = cursor; j < (BUFSIZ - 1); j++) {
 203                 if (!*(command + j))
 204                         break;
 205                 else
 206                         xwrite(outputFd, (command + j), 1);
 207         }
 208
 209         xwrite(outputFd, " \b", 2);
 210
 211         while (j-- > cursor)
 212                 xwrite(outputFd, "\b", 1);
 213         --*len;
 214 }
 215
 216 /* Move forward one charactor */
 217 void input_forward(int outputFd, int *cursor, int len)
 218 {
 219         if (*cursor < len) {
 220                 xwrite(outputFd, "\033[C", 3);
 221                 ++*cursor;
 222         }
 223 }
 224
 225 /* Move back one charactor */
 226 void input_backward(int outputFd, int *cursor)
 227 {
 228         if (*cursor > 0) {
 229                 xwrite(outputFd, "\033[D", 3);
 230                 --*cursor;
 231         }
 232 }
 233
 234
 235
 236 #ifdef BB_FEATURE_SH_TAB_COMPLETION
 237 char** username_tab_completion(char* command, int *num_matches)
 238 {
 239         char **matches = (char **) NULL;
 240         *num_matches=0;
 241         fprintf(stderr, "\nin username_tab_completion\n");
 242         return (matches);
 243 }
 244
 245 #include <dirent.h>
 246 char** exe_n_cwd_tab_completion(char* command, int *num_matches)
 247 {
 248         char *dirName;
 249         char **matches;
 250         DIR *dir;
 251         struct dirent *next;
 252
 253         matches = xmalloc( sizeof(char*)*50);
 254
 255         /* Stick a wildcard onto the command, for later use */
 256         strcat( command, "*");
 257
 258         /* Now wall the current directory */
 259         dirName = get_current_dir_name();
 260         dir = opendir(dirName);
 261         if (!dir) {
 262                 /* Don't print an error, just shut up and return */
 263                 *num_matches=0;
 264                 return (matches);
 265         }
 266         while ((next = readdir(dir)) != NULL) {
 267
 268                 /* Some quick sanity checks */
 269                 if ((strcmp(next->d_name, "..") == 0)
 270                         || (strcmp(next->d_name, ".") == 0)) {
 271                         continue;
 272                 }
 273                 /* See if this matches */
 274                 if (check_wildcard_match(next->d_name, command) == TRUE) {
 275                         /* Cool, found a match.  Add it to the list */
 276                         matches[*num_matches] = xmalloc(strlen(next->d_name)+1);
 277                         strcpy( matches[*num_matches], next->d_name);
 278                         ++*num_matches;
 279                         //matches = realloc( matches, sizeof(char*)*(*num_matches));
 280                 }
 281         }
 282
 283         return (matches);
 284 }
 285
 286 void input_tab(char* command, char* prompt, int outputFd, int *cursor, int *len)
 287 {
 288         /* Do TAB completion */
 289         static int num_matches=0;
 290         static char **matches = (char **) NULL;
 291         int pos = cursor;
 292
 293
 294         if (lastWasTab == FALSE) {
 295                 char *tmp, *tmp1, *matchBuf;
 296
 297                 /* For now, we will not bother with trying to distinguish
 298                  * whether the cursor is in/at a command extression -- we
 299                  * will always try all possible matches.  If you don't like
 300                  * that then feel free to fix it.
 301                  */
 302
 303                 /* Make a local copy of the string -- up
 304                  * to the position of the cursor */
 305                 matchBuf = (char *) xcalloc(BUFSIZ, sizeof(char));
 306                 strncpy(matchBuf, command, cursor);
 307                 tmp=matchBuf;
 308
 309                 /* skip past any command seperator tokens */
 310                 while (*tmp && (tmp1=strpbrk(tmp, ";|&{(`")) != NULL) {
 311                         tmp=++tmp1;
 312                         /* skip any leading white space */
 313                         while (*tmp && isspace(*tmp))
 314                                 ++tmp;
 315                 }
 316
 317                 /* skip any leading white space */
 318                 while (*tmp && isspace(*tmp))
 319                         ++tmp;
 320
 321                 /* Free up any memory already allocated */
 322                 if (matches) {
 323                         free(matches);
 324                         matches = (char **) NULL;
 325                 }
 326
 327                 /* If the word starts with `~' and there is no slash in the word,
 328                  * then try completing this word as a username. */
 329
 330                 /* FIXME -- this check is broken! */
 331                 if (*tmp == '~' && !strchr(tmp, '/'))
 332                         matches = username_tab_completion(tmp, &num_matches);
 333
 334                 /* Try to match any executable in our path and everything
 335                  * in the current working directory that matches.  */
 336                 if (!matches)
 337                         matches = exe_n_cwd_tab_completion(tmp, &num_matches);
 338
 339                 /* Don't leak memory */
 340                 free( matchBuf);
 341
 342                 /* Did we find exactly one match? */
 343                 if (matches && num_matches==1) {
 344                         /* write out the matched command */
 345                         strncpy(command+pos, matches[0]+pos, strlen(matches[0])-pos);
 346                         len=strlen(command);
 347                         cursor=len;
 348                         xwrite(outputFd, matches[0]+pos, strlen(matches[0])-pos);
 349                         break;
 350                 }
 351         } else {
 352                 /* Ok -- the last char was a TAB.  Since they
 353                  * just hit TAB again, print a list of all the
 354                  * available choices... */
 355                 if ( matches && num_matches>0 ) {
 356                         int i, col;
 357
 358                         /* Go to the next line */
 359                         xwrite(outputFd, "\n", 1);
 360                         /* Print the list of matches */
 361                         for (i=0,col=0; i<num_matches; i++) {
 362                                 char foo[17];
 363                                 sprintf(foo, "%-14s  ", matches[i]);
 364                                 col += xwrite(outputFd, foo, strlen(foo));
 365                                 if (col > 60 && matches[i+1] != NULL) {
 366                                         xwrite(outputFd, "\n", 1);
 367                                         col = 0;
 368                                 }
 369                         }
 370                         /* Go to the next line */
 371                         xwrite(outputFd, "\n", 1);
 372                         /* Rewrite the prompt */
 373                         xwrite(outputFd, prompt, strlen(prompt));
 374                         /* Rewrite the command */
 375                         xwrite(outputFd, command, len);
 376                         /* Put the cursor back to where it used to be */
 377                         for (cursor=len; cursor > pos; cursor--)
 378                                 xwrite(outputFd, "\b", 1);
 379                 }
 380         }
 381 }
 382 #endif
 383
 384 void get_previous_history(struct history **hp, char* command)
 385 {
 386         if ((*hp)->s)
 387                 free((*hp)->s);
 388         (*hp)->s = strdup(command);
 389         *hp = (*hp)->p;
 390 }
 391
 392 void get_next_history(struct history **hp, char* command)
 393 {
 394         if ((*hp)->s)
 395                 free((*hp)->s);
 396         (*hp)->s = strdup(command);
 397         *hp = (*hp)->n;
 398 }
 399
 400 /*
 401  * This function is used to grab a character buffer
 402  * from the input file descriptor and allows you to
 403  * a string with full command editing (sortof like
 404  * a mini readline).
 405  *
 406  * The following standard commands are not implemented:
 407  * ESC-b -- Move back one word
 408  * ESC-f -- Move forward one word
 409  * ESC-d -- Delete back one word
 410  * ESC-h -- Delete forward one word
 411  * CTL-t -- Transpose two characters
 412  *
 413  * Furthermore, the "vi" command editing keys are not implemented.
 414  *
 415  * TODO: implement TAB command completion. :)
 416  */
 417 extern void cmdedit_read_input(char* prompt, char command[BUFSIZ])
 418 {
 419
 420         int inputFd=fileno(stdin);
 421         int outputFd=fileno(stdout);
 422         int nr = 0;
 423         int len = 0;
 424         int j = 0;
 425         int cursor = 0;
 426         int break_out = 0;
 427         int ret = 0;
 428         int lastWasTab = FALSE;
 429         char c = 0;
 430         struct history *hp = his_end;
 431
 432         if (!reset_term) {
 433
 434                 getTermSettings(inputFd, (void*) &initial_settings);
 435                 memcpy(&new_settings, &initial_settings, sizeof(struct termios));
 436                 new_settings.c_cc[VMIN] = 1;
 437                 new_settings.c_cc[VTIME] = 0;
 438                 new_settings.c_cc[VINTR] = _POSIX_VDISABLE; /* Turn off CTRL-C, so we can trap it */
 439                 new_settings.c_lflag &= ~ICANON;        /* unbuffered input */
 440                 new_settings.c_lflag &= ~(ECHO|ECHOCTL|ECHONL); /* Turn off echoing */
 441                 reset_term = 1;
 442         }
 443         setTermSettings(inputFd, (void*) &new_settings);
 444
 445         memset(command, 0, BUFSIZ);
 446
 447         while (1) {
 448
 449                 if ((ret = read(inputFd, &c, 1)) < 1)
 450                         return;
 451                 //fprintf(stderr, "got a '%c' (%d)\n", c, c);
 452
 453                 switch (c) {
 454                 case '\n':
 455                 case '\r':
 456                         /* Enter */
 457                         *(command + len++ + 1) = c;
 458                         xwrite(outputFd, &c, 1);
 459                         break_out = 1;
 460                         break;
 461                 case 1:
 462                         /* Control-a -- Beginning of line */
 463                         input_home(outputFd, &cursor);
 464                 case 2:
 465                         /* Control-b -- Move back one character */
 466                         input_backward(outputFd, &cursor);
 467                         break;
 468                 case 3:
 469                         /* Control-c -- leave the current line,
 470                          * and start over on the next line */
 471
 472                         /* Go to the next line */
 473                         xwrite(outputFd, "\n", 1);
 474
 475                         /* Rewrite the prompt */
 476                         xwrite(outputFd, prompt, strlen(prompt));
 477
 478                         /* Reset the command string */
 479                         memset(command, 0, BUFSIZ);
 480                         len = cursor = 0;
 481
 482                         break;
 483                 case 4:
 484                         /* Control-d -- Delete one character, or exit
 485                          * if the len=0 and no chars to delete */
 486                         if (len == 0) {
 487                                 xwrite(outputFd, "exit", 4);
 488                                 clean_up_and_die(0);
 489                         } else {
 490                                 input_delete(command, outputFd, cursor, &len);
 491                         }
 492                         break;
 493                 case 5:
 494                         /* Control-e -- End of line */
 495                         input_end(outputFd, &cursor, len);
 496                         break;
 497                 case 6:
 498                         /* Control-f -- Move forward one character */
 499                         input_forward(outputFd, &cursor, len);
 500                         break;
 501                 case '\b':
 502                 case DEL:
 503                         /* Control-h and DEL */
 504                         input_backspace(command, outputFd, &cursor, &len);
 505                         break;
 506                 case '\t':
 507 #ifdef BB_FEATURE_SH_TAB_COMPLETION
 508                         input_tab(command, prompt, outputFd, &cursor, &len);
 509 #endif
 510                         break;
 511                 case 14:
 512                         /* Control-n -- Get next command in history */
 513                         if (hp && hp->n && hp->n->s) {
 514                                 get_next_history(&hp, command);
 515                                 goto rewrite_line;
 516                         } else {
 517                                 xwrite(outputFd, "\007", 1);
 518                         }
 519                         break;
 520                 case 16:
 521                         /* Control-p -- Get previous command from history */
 522                         if (hp && hp->p) {
 523                                 get_previous_history(&hp, command);
 524                                 goto rewrite_line;
 525                         } else {
 526                                 xwrite(outputFd, "\007", 1);
 527                         }
 528                         break;
 529                 case ESC:{
 530                                 /* escape sequence follows */
 531                                 if ((ret = read(inputFd, &c, 1)) < 1)
 532                                         return;
 533
 534                                 if (c == '[') { /* 91 */
 535                                         if ((ret = read(inputFd, &c, 1)) < 1)
 536                                                 return;
 537
 538                                         switch (c) {
 539                                         case 'A':
 540                                                 /* Up Arrow -- Get previous command from history */
 541                                                 if (hp && hp->p) {
 542                                                         get_previous_history(&hp, command);
 543                                                         goto rewrite_line;
 544                                                 } else {
 545                                                         xwrite(outputFd, "\007", 1);
 546                                                 }
 547                                                 break;
 548                                         case 'B':
 549                                                 /* Down Arrow -- Get next command in history */
 550                                                 if (hp && hp->n && hp->n->s) {
 551                                                         get_next_history(&hp, command);
 552                                                         goto rewrite_line;
 553                                                 } else {
 554                                                         xwrite(outputFd, "\007", 1);
 555                                                 }
 556                                                 break;
 557
 558                                                 /* Rewrite the line with the selected history item */
 559                                           rewrite_line:
 560                                                 /* erase old command from command line */
 561                                                 len = strlen(command)-strlen(hp->s);
 562
 563                                                 while (len>cursor)
 564                                                         input_delete(command, outputFd, cursor, &len);
 565                                                 while (cursor>0)
 566                                                         input_backspace(command, outputFd, &cursor, &len);
 567                                                 input_home(outputFd, &cursor);
 568
 569                                                 /* write new command */
 570                                                 strcpy(command, hp->s);
 571                                                 len = strlen(hp->s);
 572                                                 xwrite(outputFd, command, len);
 573                                                 cursor = len;
 574                                                 break;
 575                                         case 'C':
 576                                                 /* Right Arrow -- Move forward one character */
 577                                                 input_forward(outputFd, &cursor, len);
 578                                                 break;
 579                                         case 'D':
 580                                                 /* Left Arrow -- Move back one character */
 581                                                 input_backward(outputFd, &cursor);
 582                                                 break;
 583                                         case '3':
 584                                                 /* Delete */
 585                                                 input_delete(command, outputFd, cursor, &len);
 586                                                 break;
 587                                         case '1':
 588                                                 /* Home (Ctrl-A) */
 589                                                 input_home(outputFd, &cursor);
 590                                                 break;
 591                                         case '4':
 592                                                 /* End (Ctrl-E) */
 593                                                 input_end(outputFd, &cursor, len);
 594                                                 break;
 595                                         default:
 596                                                 xwrite(outputFd, "\007", 1);
 597                                         }
 598                                         if (c == '1' || c == '3' || c == '4')
 599                                                 if ((ret = read(inputFd, &c, 1)) < 1)
 600                                                         return; /* read 126 (~) */
 601                                 }
 602                                 if (c == 'O') {
 603                                         /* 79 */
 604                                         if ((ret = read(inputFd, &c, 1)) < 1)
 605                                                 return;
 606                                         switch (c) {
 607                                         case 'H':
 608                                                 /* Home (xterm) */
 609                                                 input_home(outputFd, &cursor);
 610                                                 break;
 611                                         case 'F':
 612                                                 /* End (xterm) */
 613                                                 input_end(outputFd, &cursor, len);
 614                                                 break;
 615                                         default:
 616                                                 xwrite(outputFd, "\007", 1);
 617                                         }
 618                                 }
 619                                 c = 0;
 620                                 break;
 621                         }
 622
 623                 default:                                /* If it's regular input, do the normal thing */
 624
 625                         if (!isprint(c)) {      /* Skip non-printable characters */
 626                                 break;
 627                         }
 628
 629                         if (len >= (BUFSIZ - 2))        /* Need to leave space for enter */
 630                                 break;
 631
 632                         len++;
 633
 634                         if (cursor == (len - 1)) {      /* Append if at the end of the line */
 635                                 *(command + cursor) = c;
 636                         } else {                        /* Insert otherwise */
 637                                 memmove(command + cursor + 1, command + cursor,
 638                                                 len - cursor - 1);
 639
 640                                 *(command + cursor) = c;
 641
 642                                 for (j = cursor; j < len; j++)
 643                                         xwrite(outputFd, command + j, 1);
 644                                 for (; j > cursor; j--)
 645                                         xwrite(outputFd, "\033[D", 3);
 646                         }
 647
 648                         cursor++;
 649                         xwrite(outputFd, &c, 1);
 650                         break;
 651                 }
 652                 if (c == '\t')
 653                         lastWasTab = TRUE;
 654                 else
 655                         lastWasTab = FALSE;
 656
 657                 if (break_out)                  /* Enter is the command terminator, no more input. */
 658                         break;
 659         }
 660
 661         nr = len + 1;
 662         setTermSettings(inputFd, (void *) &initial_settings);
 663         reset_term = 0;
 664
 665
 666         /* Handle command history log */
 667         if (*(command)) {
 668
 669                 struct history *h = his_end;
 670
 671                 if (!h) {
 672                         /* No previous history -- this memory is never freed */
 673                         h = his_front = xmalloc(sizeof(struct history));
 674                         h->n = xmalloc(sizeof(struct history));
 675
 676                         h->p = NULL;
 677                         h->s = strdup(command);
 678                         h->n->p = h;
 679                         h->n->n = NULL;
 680                         h->n->s = NULL;
 681                         his_end = h->n;
 682                         history_counter++;
 683                 } else {
 684                         /* Add a new history command -- this memory is never freed */
 685                         h->n = xmalloc(sizeof(struct history));
 686
 687                         h->n->p = h;
 688                         h->n->n = NULL;
 689                         h->n->s = NULL;
 690                         h->s = strdup(command);
 691                         his_end = h->n;
 692
 693                         /* After max history, remove the oldest command */
 694                         if (history_counter >= MAX_HISTORY) {
 695
 696                                 struct history *p = his_front->n;
 697
 698                                 p->p = NULL;
 699                                 free(his_front->s);
 700                                 free(his_front);
 701                                 his_front = p;
 702                         } else {
 703                                 history_counter++;
 704                         }
 705                 }
 706         }
 707
 708         return;
 709 }
 710
 711 extern void cmdedit_init(void)
 712 {
 713         if(exithandler_set == 0) {
 714                 atexit(cmdedit_reset_term);     /* be sure to do this only once */
 715                 exithandler_set = 1;
 716         }
 717         signal(SIGKILL, clean_up_and_die);
 718         signal(SIGINT, clean_up_and_die);
 719         signal(SIGQUIT, clean_up_and_die);
 720         signal(SIGTERM, clean_up_and_die);
 721 }
 722
 723 /*
 724 ** Undo the effects of cmdedit_init() as good as we can:
 725 ** I am not aware of a way to revoke an atexit() handler,
 726 ** but, fortunately, our particular handler can be made
 727 ** a no-op by setting reset_term = 0.
 728 */
 729 extern void cmdedit_terminate(void)
 730 {
 731         cmdedit_reset_term();
 732         reset_term = 0;
 733         signal(SIGKILL, SIG_DFL);
 734         signal(SIGINT, SIG_DFL);
 735         signal(SIGQUIT, SIG_DFL);
 736         signal(SIGTERM, SIG_DFL);
 737 }
 738
 739
 740
 741 #endif                                                  /* BB_FEATURE_SH_COMMAND_EDITING */