libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16
  17 /*
  18  * Usage and known bugs:
  19  * Terminal key codes are not extensive, more needs to be added.
  20  * This version was created on Debian GNU/Linux 2.x.
  21  * Delete, Backspace, Home, End, and the arrow keys were tested
  22  * to work in an Xterm and console. Ctrl-A also works as Home.
  23  * Ctrl-E also works as End.
  24  *
  25  * The following readline-like commands are not implemented:
  26  * ESC-b -- Move back one word
  27  * ESC-f -- Move forward one word
  28  * ESC-d -- Delete forward one word
  29  * CTL-t -- Transpose two characters
  30  *
  31  * lineedit does not know that the terminal escape sequences do not
  32  * take up space on the screen. The redisplay code assumes, unless
  33  * told otherwise, that each character in the prompt is a printable
  34  * character that takes up one character position on the screen.
  35  * You need to tell lineedit that some sequences of characters
  36  * in the prompt take up no screen space. Compatibly with readline,
  37  * use the \[ escape to begin a sequence of non-printing characters,
  38  * and the \] escape to signal the end of such a sequence. Example:
  39  *
  40  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  41  *
  42  * Unicode in PS1 is not fully supported: prompt length calulation is wrong,
  43  * resulting in line wrap problems with long (multi-line) input.
  44  *
  45  * Multi-line PS1 (e.g. PS1="\n[\w]\n$ ") has problems with history
  46  * browsing: up/down arrows result in scrolling.
  47  * It stems from simplistic "cmdedit_y = cmdedit_prmt_len / cmdedit_termw"
  48  * calculation of how many lines the prompt takes.
  49  */
  50 #include "libbb.h"
  51 #include "unicode.h"
  52 #ifndef _POSIX_VDISABLE
  53 # define _POSIX_VDISABLE '\0'
  54 #endif
  55
  56
  57 #ifdef TEST
  58 # define ENABLE_FEATURE_EDITING 0
  59 # define ENABLE_FEATURE_TAB_COMPLETION 0
  60 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  61 #endif
  62
  63
  64 /* Entire file (except TESTing part) sits inside this #if */
  65 #if ENABLE_FEATURE_EDITING
  66
  67
  68 #define ENABLE_USERNAME_OR_HOMEDIR \
  69         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  70 #define IF_USERNAME_OR_HOMEDIR(...)
  71 #if ENABLE_USERNAME_OR_HOMEDIR
  72 # undef IF_USERNAME_OR_HOMEDIR
  73 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  74 #endif
  75
  76
  77 #undef CHAR_T
  78 #if ENABLE_UNICODE_SUPPORT
  79 # define BB_NUL ((wchar_t)0)
  80 # define CHAR_T wchar_t
  81 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  82 # if ENABLE_FEATURE_EDITING_VI
  83 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  84 # endif
  85 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  86 # undef isspace
  87 # undef isalnum
  88 # undef ispunct
  89 # undef isprint
  90 # define isspace isspace_must_not_be_used
  91 # define isalnum isalnum_must_not_be_used
  92 # define ispunct ispunct_must_not_be_used
  93 # define isprint isprint_must_not_be_used
  94 #else
  95 # define BB_NUL '\0'
  96 # define CHAR_T char
  97 # define BB_isspace(c) isspace(c)
  98 # define BB_isalnum(c) isalnum(c)
  99 # define BB_ispunct(c) ispunct(c)
 100 #endif
 101 #if ENABLE_UNICODE_PRESERVE_BROKEN
 102 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
 103 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
 104 #else
 105 # define unicode_is_raw_byte(wc)     0
 106 #endif
 107
 108
 109 #define ESC "\033"
 110
 111 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 112 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 113
 114
 115 enum {
 116         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 117                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 118                       : 0x7ff0
 119 };
 120
 121 #if ENABLE_USERNAME_OR_HOMEDIR
 122 static const char null_str[] ALIGN1 = "";
 123 #endif
 124
 125 /* We try to minimize both static and stack usage. */
 126 struct lineedit_statics {
 127         line_input_t *state;
 128
 129         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 130         sighandler_t previous_SIGWINCH_handler;
 131
 132         unsigned cmdedit_x;        /* real x (col) terminal position */
 133         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 134         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 135
 136         unsigned cursor;
 137         int command_len; /* must be signed */
 138         /* signed maxsize: we want x in "if (x > S.maxsize)"
 139          * to _not_ be promoted to unsigned */
 140         int maxsize;
 141         CHAR_T *command_ps;
 142
 143         const char *cmdedit_prompt;
 144
 145 #if ENABLE_USERNAME_OR_HOMEDIR
 146         char *user_buf;
 147         char *home_pwd_buf; /* = (char*)null_str; */
 148 #endif
 149
 150 #if ENABLE_FEATURE_TAB_COMPLETION
 151         char **matches;
 152         unsigned num_matches;
 153 #endif
 154
 155 #if ENABLE_FEATURE_EDITING_VI
 156 # define DELBUFSIZ 128
 157         CHAR_T *delptr;
 158         smallint newdelflag;     /* whether delbuf should be reused yet */
 159         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 160 #endif
 161 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 162         smallint sent_ESC_br6n;
 163 #endif
 164 };
 165
 166 /* See lineedit_ptr_hack.c */
 167 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 168
 169 #define S (*lineedit_ptr_to_statics)
 170 #define state            (S.state           )
 171 #define cmdedit_termw    (S.cmdedit_termw   )
 172 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 173 #define cmdedit_x        (S.cmdedit_x       )
 174 #define cmdedit_y        (S.cmdedit_y       )
 175 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 176 #define cursor           (S.cursor          )
 177 #define command_len      (S.command_len     )
 178 #define command_ps       (S.command_ps      )
 179 #define cmdedit_prompt   (S.cmdedit_prompt  )
 180 #define user_buf         (S.user_buf        )
 181 #define home_pwd_buf     (S.home_pwd_buf    )
 182 #define matches          (S.matches         )
 183 #define num_matches      (S.num_matches     )
 184 #define delptr           (S.delptr          )
 185 #define newdelflag       (S.newdelflag      )
 186 #define delbuf           (S.delbuf          )
 187
 188 #define INIT_S() do { \
 189         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 190         barrier(); \
 191         cmdedit_termw = 80; \
 192         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 193         IF_FEATURE_EDITING_VI(delptr = delbuf;) \
 194 } while (0)
 195
 196 static void deinit_S(void)
 197 {
 198 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 199         /* This one is allocated only if FANCY_PROMPT is on
 200          * (otherwise it points to verbatim prompt (NOT malloced)) */
 201         free((char*)cmdedit_prompt);
 202 #endif
 203 #if ENABLE_USERNAME_OR_HOMEDIR
 204         free(user_buf);
 205         if (home_pwd_buf != null_str)
 206                 free(home_pwd_buf);
 207 #endif
 208         free(lineedit_ptr_to_statics);
 209 }
 210 #define DEINIT_S() deinit_S()
 211
 212
 213 #if ENABLE_UNICODE_SUPPORT
 214 static size_t load_string(const char *src)
 215 {
 216         if (unicode_status == UNICODE_ON) {
 217                 ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
 218                 if (len < 0)
 219                         len = 0;
 220                 command_ps[len] = BB_NUL;
 221                 return len;
 222         } else {
 223                 unsigned i = 0;
 224                 while (src[i] && i < S.maxsize - 1) {
 225                         command_ps[i] = src[i];
 226                         i++;
 227                 }
 228                 command_ps[i] = BB_NUL;
 229                 return i;
 230         }
 231 }
 232 static unsigned save_string(char *dst, unsigned maxsize)
 233 {
 234         if (unicode_status == UNICODE_ON) {
 235 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 236                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 237                 if (len < 0)
 238                         len = 0;
 239                 dst[len] = '\0';
 240                 return len;
 241 # else
 242                 unsigned dstpos = 0;
 243                 unsigned srcpos = 0;
 244
 245                 maxsize--;
 246                 while (dstpos < maxsize) {
 247                         wchar_t wc;
 248                         int n = srcpos;
 249
 250                         /* Convert up to 1st invalid byte (or up to end) */
 251                         while ((wc = command_ps[srcpos]) != BB_NUL
 252                             && !unicode_is_raw_byte(wc)
 253                         ) {
 254                                 srcpos++;
 255                         }
 256                         command_ps[srcpos] = BB_NUL;
 257                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 258                         if (n < 0) /* should not happen */
 259                                 break;
 260                         dstpos += n;
 261                         if (wc == BB_NUL) /* usually is */
 262                                 break;
 263
 264                         /* We do have invalid byte here! */
 265                         command_ps[srcpos] = wc; /* restore it */
 266                         srcpos++;
 267                         if (dstpos == maxsize)
 268                                 break;
 269                         dst[dstpos++] = (char) wc;
 270                 }
 271                 dst[dstpos] = '\0';
 272                 return dstpos;
 273 # endif
 274         } else {
 275                 unsigned i = 0;
 276                 while ((dst[i] = command_ps[i]) != 0)
 277                         i++;
 278                 return i;
 279         }
 280 }
 281 /* I thought just fputwc(c, stdout) would work. But no... */
 282 static void BB_PUTCHAR(wchar_t c)
 283 {
 284         if (unicode_status == UNICODE_ON) {
 285                 char buf[MB_CUR_MAX + 1];
 286                 mbstate_t mbst = { 0 };
 287                 ssize_t len = wcrtomb(buf, c, &mbst);
 288                 if (len > 0) {
 289                         buf[len] = '\0';
 290                         fputs(buf, stdout);
 291                 }
 292         } else {
 293                 /* In this case, c is always one byte */
 294                 putchar(c);
 295         }
 296 }
 297 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 298 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 299 # else
 300 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 301 #  define adjust_width_and_validate_wc(width_adj, wc) \
 302         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 303 # endif
 304 {
 305         int w = 1;
 306
 307         if (unicode_status == UNICODE_ON) {
 308                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 309                         /* note: also true for unicode_is_raw_byte(wc) */
 310                         goto subst;
 311                 }
 312                 w = wcwidth(wc);
 313                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 314                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 315                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 316                 ) {
 317  subst:
 318                         w = 1;
 319                         wc = CONFIG_SUBST_WCHAR;
 320                 }
 321         }
 322
 323 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 324         *width_adj += w;
 325 #endif
 326         return wc;
 327 }
 328 #else /* !UNICODE */
 329 static size_t load_string(const char *src)
 330 {
 331         safe_strncpy(command_ps, src, S.maxsize);
 332         return strlen(command_ps);
 333 }
 334 # if ENABLE_FEATURE_TAB_COMPLETION
 335 static void save_string(char *dst, unsigned maxsize)
 336 {
 337         safe_strncpy(dst, command_ps, maxsize);
 338 }
 339 # endif
 340 # define BB_PUTCHAR(c) bb_putchar(c)
 341 /* Should never be called: */
 342 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 343 #endif
 344
 345
 346 /* Put 'command_ps[cursor]', cursor++.
 347  * Advance cursor on screen. If we reached right margin, scroll text up
 348  * and remove terminal margin effect by printing 'next_char' */
 349 #define HACK_FOR_WRONG_WIDTH 1
 350 static void put_cur_glyph_and_inc_cursor(void)
 351 {
 352         CHAR_T c = command_ps[cursor];
 353         unsigned width = 0;
 354         int ofs_to_right;
 355
 356         if (c == BB_NUL) {
 357                 /* erase character after end of input string */
 358                 c = ' ';
 359         } else {
 360                 /* advance cursor only if we aren't at the end yet */
 361                 cursor++;
 362                 if (unicode_status == UNICODE_ON) {
 363                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 364                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 365                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 366                 } else {
 367                         cmdedit_x++;
 368                 }
 369         }
 370
 371         ofs_to_right = cmdedit_x - cmdedit_termw;
 372         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 373                 /* c fits on this line */
 374                 BB_PUTCHAR(c);
 375         }
 376
 377         if (ofs_to_right >= 0) {
 378                 /* we go to the next line */
 379 #if HACK_FOR_WRONG_WIDTH
 380                 /* This works better if our idea of term width is wrong
 381                  * and it is actually wider (often happens on serial lines).
 382                  * Printing CR,LF *forces* cursor to next line.
 383                  * OTOH if terminal width is correct AND terminal does NOT
 384                  * have automargin (IOW: it is moving cursor to next line
 385                  * by itself (which is wrong for VT-10x terminals)),
 386                  * this will break things: there will be one extra empty line */
 387                 puts("\r"); /* + implicit '\n' */
 388 #else
 389                 /* VT-10x terminals don't wrap cursor to next line when last char
 390                  * on the line is printed - cursor stays "over" this char.
 391                  * Need to print _next_ char too (first one to appear on next line)
 392                  * to make cursor move down to next line.
 393                  */
 394                 /* Works ok only if cmdedit_termw is correct. */
 395                 c = command_ps[cursor];
 396                 if (c == BB_NUL)
 397                         c = ' ';
 398                 BB_PUTCHAR(c);
 399                 bb_putchar('\b');
 400 #endif
 401                 cmdedit_y++;
 402                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 403                         width = 0;
 404                 } else { /* ofs_to_right > 0 */
 405                         /* wide char c didn't fit on prev line */
 406                         BB_PUTCHAR(c);
 407                 }
 408                 cmdedit_x = width;
 409         }
 410 }
 411
 412 /* Move to end of line (by printing all chars till the end) */
 413 static void put_till_end_and_adv_cursor(void)
 414 {
 415         while (cursor < command_len)
 416                 put_cur_glyph_and_inc_cursor();
 417 }
 418
 419 /* Go to the next line */
 420 static void goto_new_line(void)
 421 {
 422         put_till_end_and_adv_cursor();
 423         if (cmdedit_x != 0)
 424                 bb_putchar('\n');
 425 }
 426
 427 static void beep(void)
 428 {
 429         bb_putchar('\007');
 430 }
 431
 432 static void put_prompt(void)
 433 {
 434         unsigned w;
 435
 436         fputs(cmdedit_prompt, stdout);
 437         fflush_all();
 438         cursor = 0;
 439         w = cmdedit_termw; /* read volatile var once */
 440         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 441         cmdedit_x = cmdedit_prmt_len % w;
 442 }
 443
 444 /* Move back one character */
 445 /* (optimized for slow terminals) */
 446 static void input_backward(unsigned num)
 447 {
 448         if (num > cursor)
 449                 num = cursor;
 450         if (num == 0)
 451                 return;
 452         cursor -= num;
 453
 454         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 455          && unicode_status == UNICODE_ON
 456         ) {
 457                 /* correct NUM to be equal to _screen_ width */
 458                 int n = num;
 459                 num = 0;
 460                 while (--n >= 0)
 461                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 462                 if (num == 0)
 463                         return;
 464         }
 465
 466         if (cmdedit_x >= num) {
 467                 cmdedit_x -= num;
 468                 if (num <= 4) {
 469                         /* This is longer by 5 bytes on x86.
 470                          * Also gets miscompiled for ARM users
 471                          * (busybox.net/bugs/view.php?id=2274).
 472                          * printf(("\b\b\b\b" + 4) - num);
 473                          * return;
 474                          */
 475                         do {
 476                                 bb_putchar('\b');
 477                         } while (--num);
 478                         return;
 479                 }
 480                 printf(ESC"[%uD", num);
 481                 return;
 482         }
 483
 484         /* Need to go one or more lines up */
 485         if (ENABLE_UNICODE_WIDE_WCHARS) {
 486                 /* With wide chars, it is hard to "backtrack"
 487                  * and reliably figure out where to put cursor.
 488                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 489                  * |prompt: <><> |
 490                  * |<><><><><><> |
 491                  * |_            |
 492                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 493                  * We need to go up one line, and then - how do we know that
 494                  * we need to go *10* positions to the right? Because
 495                  * |prompt: <>#<>|
 496                  * |<><><>#<><><>|
 497                  * |_            |
 498                  * in this situation we need to go *11* positions to the right.
 499                  *
 500                  * A simpler thing to do is to redraw everything from the start
 501                  * up to new cursor position (which is already known):
 502                  */
 503                 unsigned sv_cursor;
 504                 /* go to 1st column; go up to first line */
 505                 printf("\r" ESC"[%uA", cmdedit_y);
 506                 cmdedit_y = 0;
 507                 sv_cursor = cursor;
 508                 put_prompt(); /* sets cursor to 0 */
 509                 while (cursor < sv_cursor)
 510                         put_cur_glyph_and_inc_cursor();
 511         } else {
 512                 int lines_up;
 513                 unsigned width;
 514                 /* num = chars to go back from the beginning of current line: */
 515                 num -= cmdedit_x;
 516                 width = cmdedit_termw; /* read volatile var once */
 517                 /* num=1...w: one line up, w+1...2w: two, etc: */
 518                 lines_up = 1 + (num - 1) / width;
 519                 cmdedit_x = (width * cmdedit_y - num) % width;
 520                 cmdedit_y -= lines_up;
 521                 /* go to 1st column; go up */
 522                 printf("\r" ESC"[%uA", lines_up);
 523                 /* go to correct column.
 524                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 525                  * need to *make sure* we skip it if cmdedit_x == 0 */
 526                 if (cmdedit_x)
 527                         printf(ESC"[%uC", cmdedit_x);
 528         }
 529 }
 530
 531 /* draw prompt, editor line, and clear tail */
 532 static void redraw(int y, int back_cursor)
 533 {
 534         if (y > 0) /* up y lines */
 535                 printf(ESC"[%uA", y);
 536         bb_putchar('\r');
 537         put_prompt();
 538         put_till_end_and_adv_cursor();
 539         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 540         input_backward(back_cursor);
 541 }
 542
 543 /* Delete the char in front of the cursor, optionally saving it
 544  * for later putback */
 545 #if !ENABLE_FEATURE_EDITING_VI
 546 static void input_delete(void)
 547 #define input_delete(save) input_delete()
 548 #else
 549 static void input_delete(int save)
 550 #endif
 551 {
 552         int j = cursor;
 553
 554         if (j == (int)command_len)
 555                 return;
 556
 557 #if ENABLE_FEATURE_EDITING_VI
 558         if (save) {
 559                 if (newdelflag) {
 560                         delptr = delbuf;
 561                         newdelflag = 0;
 562                 }
 563                 if ((delptr - delbuf) < DELBUFSIZ)
 564                         *delptr++ = command_ps[j];
 565         }
 566 #endif
 567
 568         memmove(command_ps + j, command_ps + j + 1,
 569                         /* (command_len + 1 [because of NUL]) - (j + 1)
 570                          * simplified into (command_len - j) */
 571                         (command_len - j) * sizeof(command_ps[0]));
 572         command_len--;
 573         put_till_end_and_adv_cursor();
 574         /* Last char is still visible, erase it (and more) */
 575         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 576         input_backward(cursor - j);     /* back to old pos cursor */
 577 }
 578
 579 #if ENABLE_FEATURE_EDITING_VI
 580 static void put(void)
 581 {
 582         int ocursor;
 583         int j = delptr - delbuf;
 584
 585         if (j == 0)
 586                 return;
 587         ocursor = cursor;
 588         /* open hole and then fill it */
 589         memmove(command_ps + cursor + j, command_ps + cursor,
 590                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 591         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 592         command_len += j;
 593         put_till_end_and_adv_cursor();
 594         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 595 }
 596 #endif
 597
 598 /* Delete the char in back of the cursor */
 599 static void input_backspace(void)
 600 {
 601         if (cursor > 0) {
 602                 input_backward(1);
 603                 input_delete(0);
 604         }
 605 }
 606
 607 /* Move forward one character */
 608 static void input_forward(void)
 609 {
 610         if (cursor < command_len)
 611                 put_cur_glyph_and_inc_cursor();
 612 }
 613
 614 #if ENABLE_FEATURE_TAB_COMPLETION
 615
 616 //FIXME:
 617 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 618 //matches the file named "foo bar", which is untrue.
 619 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 620 //not "foo bar <cursor>...
 621
 622 static void free_tab_completion_data(void)
 623 {
 624         if (matches) {
 625                 while (num_matches)
 626                         free(matches[--num_matches]);
 627                 free(matches);
 628                 matches = NULL;
 629         }
 630 }
 631
 632 static void add_match(char *matched)
 633 {
 634         matches = xrealloc_vector(matches, 4, num_matches);
 635         matches[num_matches] = matched;
 636         num_matches++;
 637 }
 638
 639 # if ENABLE_FEATURE_USERNAME_COMPLETION
 640 /* Replace "~user/..." with "/homedir/...".
 641  * The parameter is malloced, free it or return it
 642  * unchanged if no user is matched.
 643  */
 644 static char *username_path_completion(char *ud)
 645 {
 646         struct passwd *entry;
 647         char *tilde_name = ud;
 648         char *home = NULL;
 649
 650         ud++; /* skip ~ */
 651         if (*ud == '/') {       /* "~/..." */
 652                 home = home_pwd_buf;
 653         } else {
 654                 /* "~user/..." */
 655                 ud = strchr(ud, '/');
 656                 *ud = '\0';           /* "~user" */
 657                 entry = getpwnam(tilde_name + 1);
 658                 *ud = '/';            /* restore "~user/..." */
 659                 if (entry)
 660                         home = entry->pw_dir;
 661         }
 662         if (home) {
 663                 ud = concat_path_file(home, ud);
 664                 free(tilde_name);
 665                 tilde_name = ud;
 666         }
 667         return tilde_name;
 668 }
 669
 670 /* ~use<tab> - find all users with this prefix.
 671  * Return the length of the prefix used for matching.
 672  */
 673 static NOINLINE unsigned complete_username(const char *ud)
 674 {
 675         /* Using _r function to avoid pulling in static buffers */
 676         char line_buff[256];
 677         struct passwd pwd;
 678         struct passwd *result;
 679         unsigned userlen;
 680
 681         ud++; /* skip ~ */
 682         userlen = strlen(ud);
 683
 684         setpwent();
 685         while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
 686                 /* Null usernames should result in all users as possible completions. */
 687                 if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
 688                         add_match(xasprintf("~%s/", pwd.pw_name));
 689                 }
 690         }
 691         endpwent();
 692
 693         return 1 + userlen;
 694 }
 695 # endif  /* FEATURE_USERNAME_COMPLETION */
 696
 697 enum {
 698         FIND_EXE_ONLY = 0,
 699         FIND_DIR_ONLY = 1,
 700         FIND_FILE_ONLY = 2,
 701 };
 702
 703 static int path_parse(char ***p)
 704 {
 705         int npth;
 706         const char *pth;
 707         char *tmp;
 708         char **res;
 709
 710         if (state->flags & WITH_PATH_LOOKUP)
 711                 pth = state->path_lookup;
 712         else
 713                 pth = getenv("PATH");
 714
 715         /* PATH="" or PATH=":"? */
 716         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 717                 return 1;
 718
 719         tmp = (char*)pth;
 720         npth = 1; /* path component count */
 721         while (1) {
 722                 tmp = strchr(tmp, ':');
 723                 if (!tmp)
 724                         break;
 725                 tmp++;
 726                 if (*tmp == '\0')
 727                         break;  /* :<empty> */
 728                 npth++;
 729         }
 730
 731         *p = res = xmalloc(npth * sizeof(res[0]));
 732         res[0] = tmp = xstrdup(pth);
 733         npth = 1;
 734         while (1) {
 735                 tmp = strchr(tmp, ':');
 736                 if (!tmp)
 737                         break;
 738                 *tmp++ = '\0'; /* ':' -> '\0' */
 739                 if (*tmp == '\0')
 740                         break; /* :<empty> */
 741                 res[npth++] = tmp;
 742         }
 743         return npth;
 744 }
 745
 746 /* Complete command, directory or file name.
 747  * Return the length of the prefix used for matching.
 748  */
 749 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 750 {
 751         char *path1[1];
 752         char **paths = path1;
 753         int npaths;
 754         int i;
 755         unsigned pf_len;
 756         const char *pfind;
 757         char *dirbuf = NULL;
 758
 759         npaths = 1;
 760         path1[0] = (char*)".";
 761
 762         pfind = strrchr(command, '/');
 763         if (!pfind) {
 764                 if (type == FIND_EXE_ONLY)
 765                         npaths = path_parse(&paths);
 766                 pfind = command;
 767         } else {
 768                 /* point to 'l' in "..../last_component" */
 769                 pfind++;
 770                 /* dirbuf = ".../.../.../" */
 771                 dirbuf = xstrndup(command, pfind - command);
 772 # if ENABLE_FEATURE_USERNAME_COMPLETION
 773                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 774                         dirbuf = username_path_completion(dirbuf);
 775 # endif
 776                 path1[0] = dirbuf;
 777         }
 778         pf_len = strlen(pfind);
 779
 780         for (i = 0; i < npaths; i++) {
 781                 DIR *dir;
 782                 struct dirent *next;
 783                 struct stat st;
 784                 char *found;
 785
 786                 dir = opendir(paths[i]);
 787                 if (!dir)
 788                         continue; /* don't print an error */
 789
 790                 while ((next = readdir(dir)) != NULL) {
 791                         unsigned len;
 792                         const char *name_found = next->d_name;
 793
 794                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 795                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 796                                 continue;
 797                         /* match? */
 798                         if (strncmp(name_found, pfind, pf_len) != 0)
 799                                 continue; /* no */
 800
 801                         found = concat_path_file(paths[i], name_found);
 802                         /* NB: stat() first so that we see is it a directory;
 803                          * but if that fails, use lstat() so that
 804                          * we still match dangling links */
 805                         if (stat(found, &st) && lstat(found, &st))
 806                                 goto cont; /* hmm, remove in progress? */
 807
 808                         /* Save only name */
 809                         len = strlen(name_found);
 810                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 811                         strcpy(found, name_found);
 812
 813                         if (S_ISDIR(st.st_mode)) {
 814                                 /* name is a directory, add slash */
 815                                 found[len] = '/';
 816                                 found[len + 1] = '\0';
 817                         } else {
 818                                 /* skip files if looking for dirs only (example: cd) */
 819                                 if (type == FIND_DIR_ONLY)
 820                                         goto cont;
 821                         }
 822                         /* add it to the list */
 823                         add_match(found);
 824                         continue;
 825  cont:
 826                         free(found);
 827                 }
 828                 closedir(dir);
 829         } /* for every path */
 830
 831         if (paths != path1) {
 832                 free(paths[0]); /* allocated memory is only in first member */
 833                 free(paths);
 834         }
 835         free(dirbuf);
 836
 837         return pf_len;
 838 }
 839
 840 /* build_match_prefix:
 841  * On entry, match_buf contains everything up to cursor at the moment <tab>
 842  * was pressed. This function looks at it, figures out what part of it
 843  * constitutes the command/file/directory prefix to use for completion,
 844  * and rewrites match_buf to contain only that part.
 845  */
 846 #define dbg_bmp 0
 847 /* Helpers: */
 848 /* QUOT is used on elements of int_buf[], which are bytes,
 849  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 850  */
 851 #define QUOT (UCHAR_MAX+1)
 852 static void remove_chunk(int16_t *int_buf, int beg, int end)
 853 {
 854         /* beg must be <= end */
 855         if (beg == end)
 856                 return;
 857
 858         while ((int_buf[beg] = int_buf[end]) != 0)
 859                 beg++, end++;
 860
 861         if (dbg_bmp) {
 862                 int i;
 863                 for (i = 0; int_buf[i]; i++)
 864                         bb_putchar((unsigned char)int_buf[i]);
 865                 bb_putchar('\n');
 866         }
 867 }
 868 /* Caller ensures that match_buf points to a malloced buffer
 869  * big enough to hold strlen(match_buf)*2 + 2
 870  */
 871 static NOINLINE int build_match_prefix(char *match_buf)
 872 {
 873         int i, j;
 874         int command_mode;
 875         int16_t *int_buf = (int16_t*)match_buf;
 876
 877         if (dbg_bmp) printf("\n%s\n", match_buf);
 878
 879         /* Copy in reverse order, since they overlap */
 880         i = strlen(match_buf);
 881         do {
 882                 int_buf[i] = (unsigned char)match_buf[i];
 883                 i--;
 884         } while (i >= 0);
 885
 886         /* Mark every \c as "quoted c" */
 887         for (i = 0; int_buf[i]; i++) {
 888                 if (int_buf[i] == '\\') {
 889                         remove_chunk(int_buf, i, i + 1);
 890                         int_buf[i] |= QUOT;
 891                 }
 892         }
 893         /* Quote-mark "chars" and 'chars', drop delimiters */
 894         {
 895                 int in_quote = 0;
 896                 i = 0;
 897                 while (int_buf[i]) {
 898                         int cur = int_buf[i];
 899                         if (!cur)
 900                                 break;
 901                         if (cur == '\'' || cur == '"') {
 902                                 if (!in_quote || (cur == in_quote)) {
 903                                         in_quote ^= cur;
 904                                         remove_chunk(int_buf, i, i + 1);
 905                                         continue;
 906                                 }
 907                         }
 908                         if (in_quote)
 909                                 int_buf[i] = cur | QUOT;
 910                         i++;
 911                 }
 912         }
 913
 914         /* Remove everything up to command delimiters:
 915          * ';' ';;' '&' '|' '&&' '||',
 916          * but careful with '>&' '<&' '>|'
 917          */
 918         for (i = 0; int_buf[i]; i++) {
 919                 int cur = int_buf[i];
 920                 if (cur == ';' || cur == '&' || cur == '|') {
 921                         int prev = i ? int_buf[i - 1] : 0;
 922                         if (cur == '&' && (prev == '>' || prev == '<')) {
 923                                 continue;
 924                         } else if (cur == '|' && prev == '>') {
 925                                 continue;
 926                         }
 927                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 928                         i = -1;  /* back to square 1 */
 929                 }
 930         }
 931         /* Remove all `cmd` */
 932         for (i = 0; int_buf[i]; i++) {
 933                 if (int_buf[i] == '`') {
 934                         for (j = i + 1; int_buf[j]; j++) {
 935                                 if (int_buf[j] == '`') {
 936                                         /* `cmd` should count as a word:
 937                                          * `cmd` c<tab> should search for files c*,
 938                                          * not commands c*. Therefore we don't drop
 939                                          * `cmd` entirely, we replace it with single `.
 940                                          */
 941                                         remove_chunk(int_buf, i, j);
 942                                         goto next;
 943                                 }
 944                         }
 945                         /* No closing ` - command mode, remove all up to ` */
 946                         remove_chunk(int_buf, 0, i + 1);
 947                         break;
 948  next: ;
 949                 }
 950         }
 951
 952         /* Remove "cmd (" and "cmd {"
 953          * Example: "if { c<tab>"
 954          * In this example, c should be matched as command pfx.
 955          */
 956         for (i = 0; int_buf[i]; i++) {
 957                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 958                         remove_chunk(int_buf, 0, i + 1);
 959                         i = -1;  /* back to square 1 */
 960                 }
 961         }
 962
 963         /* Remove leading unquoted spaces */
 964         for (i = 0; int_buf[i]; i++)
 965                 if (int_buf[i] != ' ')
 966                         break;
 967         remove_chunk(int_buf, 0, i);
 968
 969         /* Determine completion mode */
 970         command_mode = FIND_EXE_ONLY;
 971         for (i = 0; int_buf[i]; i++) {
 972                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 973                         if (int_buf[i] == ' '
 974                          && command_mode == FIND_EXE_ONLY
 975                          && (char)int_buf[0] == 'c'
 976                          && (char)int_buf[1] == 'd'
 977                          && i == 2 /* -> int_buf[2] == ' ' */
 978                         ) {
 979                                 command_mode = FIND_DIR_ONLY;
 980                         } else {
 981                                 command_mode = FIND_FILE_ONLY;
 982                                 break;
 983                         }
 984                 }
 985         }
 986         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 987
 988         /* Remove everything except last word */
 989         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
 990                 continue;
 991         for (--i; i >= 0; i--) {
 992                 int cur = int_buf[i];
 993                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
 994                         remove_chunk(int_buf, 0, i + 1);
 995                         break;
 996                 }
 997         }
 998
 999         /* Convert back to string of _chars_ */
1000         i = 0;
1001         while ((match_buf[i] = int_buf[i]) != '\0')
1002                 i++;
1003
1004         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
1005
1006         return command_mode;
1007 }
1008
1009 /*
1010  * Display by column (original idea from ls applet,
1011  * very optimized by me [Vladimir] :)
1012  */
1013 static void showfiles(void)
1014 {
1015         int ncols, row;
1016         int column_width = 0;
1017         int nfiles = num_matches;
1018         int nrows = nfiles;
1019         int l;
1020
1021         /* find the longest file name - use that as the column width */
1022         for (row = 0; row < nrows; row++) {
1023                 l = unicode_strwidth(matches[row]);
1024                 if (column_width < l)
1025                         column_width = l;
1026         }
1027         column_width += 2;              /* min space for columns */
1028         ncols = cmdedit_termw / column_width;
1029
1030         if (ncols > 1) {
1031                 nrows /= ncols;
1032                 if (nfiles % ncols)
1033                         nrows++;        /* round up fractionals */
1034         } else {
1035                 ncols = 1;
1036         }
1037         for (row = 0; row < nrows; row++) {
1038                 int n = row;
1039                 int nc;
1040
1041                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1042                         printf("%s%-*s", matches[n],
1043                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1044                         );
1045                 }
1046                 if (ENABLE_UNICODE_SUPPORT)
1047                         puts(printable_string(NULL, matches[n]));
1048                 else
1049                         puts(matches[n]);
1050         }
1051 }
1052
1053 static const char *is_special_char(char c)
1054 {
1055         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1056 }
1057
1058 static char *quote_special_chars(char *found)
1059 {
1060         int l = 0;
1061         char *s = xzalloc((strlen(found) + 1) * 2);
1062
1063         while (*found) {
1064                 if (is_special_char(*found))
1065                         s[l++] = '\\';
1066                 s[l++] = *found++;
1067         }
1068         /* s[l] = '\0'; - already is */
1069         return s;
1070 }
1071
1072 /* Do TAB completion */
1073 static NOINLINE void input_tab(smallint *lastWasTab)
1074 {
1075         char *chosen_match;
1076         char *match_buf;
1077         size_t len_found;
1078         /* Length of string used for matching */
1079         unsigned match_pfx_len = match_pfx_len;
1080         int find_type;
1081 # if ENABLE_UNICODE_SUPPORT
1082         /* cursor pos in command converted to multibyte form */
1083         int cursor_mb;
1084 # endif
1085         if (!(state->flags & TAB_COMPLETION))
1086                 return;
1087
1088         if (*lastWasTab) {
1089                 /* The last char was a TAB too.
1090                  * Print a list of all the available choices.
1091                  */
1092                 if (num_matches > 0) {
1093                         /* cursor will be changed by goto_new_line() */
1094                         int sav_cursor = cursor;
1095                         goto_new_line();
1096                         showfiles();
1097                         redraw(0, command_len - sav_cursor);
1098                 }
1099                 return;
1100         }
1101
1102         *lastWasTab = 1;
1103         chosen_match = NULL;
1104
1105         /* Make a local copy of the string up to the position of the cursor.
1106          * build_match_prefix will expand it into int16_t's, need to allocate
1107          * twice as much as the string_len+1.
1108          * (we then also (ab)use this extra space later - see (**))
1109          */
1110         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1111 # if !ENABLE_UNICODE_SUPPORT
1112         save_string(match_buf, cursor + 1); /* +1 for NUL */
1113 # else
1114         {
1115                 CHAR_T wc = command_ps[cursor];
1116                 command_ps[cursor] = BB_NUL;
1117                 save_string(match_buf, MAX_LINELEN);
1118                 command_ps[cursor] = wc;
1119                 cursor_mb = strlen(match_buf);
1120         }
1121 # endif
1122         find_type = build_match_prefix(match_buf);
1123
1124         /* Free up any memory already allocated */
1125         free_tab_completion_data();
1126
1127 # if ENABLE_FEATURE_USERNAME_COMPLETION
1128         /* If the word starts with ~ and there is no slash in the word,
1129          * then try completing this word as a username. */
1130         if (state->flags & USERNAME_COMPLETION)
1131                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1132                         match_pfx_len = complete_username(match_buf);
1133 # endif
1134         /* If complete_username() did not match,
1135          * try to match a command in $PATH, or a directory, or a file */
1136         if (!matches)
1137                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1138
1139         /* Account for backslashes which will be inserted
1140          * by quote_special_chars() later */
1141         {
1142                 const char *e = match_buf + strlen(match_buf);
1143                 const char *s = e - match_pfx_len;
1144                 while (s < e)
1145                         if (is_special_char(*s++))
1146                                 match_pfx_len++;
1147         }
1148
1149         /* Remove duplicates */
1150         if (matches) {
1151                 unsigned i, n = 0;
1152                 qsort_string_vector(matches, num_matches);
1153                 for (i = 0; i < num_matches - 1; ++i) {
1154                         //if (matches[i] && matches[i+1]) { /* paranoia */
1155                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1156                                         free(matches[i]);
1157                                         //matches[i] = NULL; /* paranoia */
1158                                 } else {
1159                                         matches[n++] = matches[i];
1160                                 }
1161                         //}
1162                 }
1163                 matches[n++] = matches[i];
1164                 num_matches = n;
1165         }
1166
1167         /* Did we find exactly one match? */
1168         if (num_matches != 1) { /* no */
1169                 char *cp;
1170                 beep();
1171                 if (!matches)
1172                         goto ret; /* no matches at all */
1173                 /* Find common prefix */
1174                 chosen_match = xstrdup(matches[0]);
1175                 for (cp = chosen_match; *cp; cp++) {
1176                         unsigned n;
1177                         for (n = 1; n < num_matches; n++) {
1178                                 if (matches[n][cp - chosen_match] != *cp) {
1179                                         goto stop;
1180                                 }
1181                         }
1182                 }
1183  stop:
1184                 if (cp == chosen_match) { /* have unique prefix? */
1185                         goto ret; /* no */
1186                 }
1187                 *cp = '\0';
1188                 cp = quote_special_chars(chosen_match);
1189                 free(chosen_match);
1190                 chosen_match = cp;
1191                 len_found = strlen(chosen_match);
1192         } else {                        /* exactly one match */
1193                 /* Next <tab> is not a double-tab */
1194                 *lastWasTab = 0;
1195
1196                 chosen_match = quote_special_chars(matches[0]);
1197                 len_found = strlen(chosen_match);
1198                 if (chosen_match[len_found-1] != '/') {
1199                         chosen_match[len_found] = ' ';
1200                         chosen_match[++len_found] = '\0';
1201                 }
1202         }
1203
1204 # if !ENABLE_UNICODE_SUPPORT
1205         /* Have space to place the match? */
1206         /* The result consists of three parts with these lengths: */
1207         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1208         /* it simplifies into: */
1209         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1210                 int pos;
1211                 /* save tail */
1212                 strcpy(match_buf, &command_ps[cursor]);
1213                 /* add match and tail */
1214                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1215                 command_len = strlen(command_ps);
1216                 /* new pos */
1217                 pos = cursor + len_found - match_pfx_len;
1218                 /* write out the matched command */
1219                 redraw(cmdedit_y, command_len - pos);
1220         }
1221 # else
1222         {
1223                 /* Use 2nd half of match_buf as scratch space - see (**) */
1224                 char *command = match_buf + MAX_LINELEN;
1225                 int len = save_string(command, MAX_LINELEN);
1226                 /* Have space to place the match? */
1227                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1228                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1229                         int pos;
1230                         /* save tail */
1231                         strcpy(match_buf, &command[cursor_mb]);
1232                         /* where do we want to have cursor after all? */
1233                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1234                         len = load_string(command);
1235                         /* add match and tail */
1236                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1237                         command_len = load_string(command);
1238                         /* write out the matched command */
1239                         /* paranoia: load_string can return 0 on conv error,
1240                          * prevent passing pos = (0 - 12) to redraw */
1241                         pos = command_len - len;
1242                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1243                 }
1244         }
1245 # endif
1246  ret:
1247         free(chosen_match);
1248         free(match_buf);
1249 }
1250
1251 #endif  /* FEATURE_TAB_COMPLETION */
1252
1253
1254 line_input_t* FAST_FUNC new_line_input_t(int flags)
1255 {
1256         line_input_t *n = xzalloc(sizeof(*n));
1257         n->flags = flags;
1258 #if MAX_HISTORY > 0
1259         n->max_history = MAX_HISTORY;
1260 #endif
1261         return n;
1262 }
1263
1264
1265 #if MAX_HISTORY > 0
1266
1267 unsigned FAST_FUNC size_from_HISTFILESIZE(const char *hp)
1268 {
1269         int size = MAX_HISTORY;
1270         if (hp) {
1271                 size = atoi(hp);
1272                 if (size <= 0)
1273                         return 1;
1274                 if (size > MAX_HISTORY)
1275                         return MAX_HISTORY;
1276         }
1277         return size;
1278 }
1279
1280 static void save_command_ps_at_cur_history(void)
1281 {
1282         if (command_ps[0] != BB_NUL) {
1283                 int cur = state->cur_history;
1284                 free(state->history[cur]);
1285
1286 # if ENABLE_UNICODE_SUPPORT
1287                 {
1288                         char tbuf[MAX_LINELEN];
1289                         save_string(tbuf, sizeof(tbuf));
1290                         state->history[cur] = xstrdup(tbuf);
1291                 }
1292 # else
1293                 state->history[cur] = xstrdup(command_ps);
1294 # endif
1295         }
1296 }
1297
1298 /* state->flags is already checked to be nonzero */
1299 static int get_previous_history(void)
1300 {
1301         if ((state->flags & DO_HISTORY) && state->cur_history) {
1302                 save_command_ps_at_cur_history();
1303                 state->cur_history--;
1304                 return 1;
1305         }
1306         beep();
1307         return 0;
1308 }
1309
1310 static int get_next_history(void)
1311 {
1312         if (state->flags & DO_HISTORY) {
1313                 if (state->cur_history < state->cnt_history) {
1314                         save_command_ps_at_cur_history(); /* save the current history line */
1315                         return ++state->cur_history;
1316                 }
1317         }
1318         beep();
1319         return 0;
1320 }
1321
1322 /* Lists command history. Used by shell 'history' builtins */
1323 void FAST_FUNC show_history(const line_input_t *st)
1324 {
1325         int i;
1326
1327         if (!st)
1328                 return;
1329         for (i = 0; i < st->cnt_history; i++)
1330                 printf("%4d %s\n", i, st->history[i]);
1331 }
1332
1333 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1334 /* We try to ensure that concurrent additions to the history
1335  * do not overwrite each other.
1336  * Otherwise shell users get unhappy.
1337  *
1338  * History file is trimmed lazily, when it grows several times longer
1339  * than configured MAX_HISTORY lines.
1340  */
1341
1342 static void free_line_input_t(line_input_t *n)
1343 {
1344         int i = n->cnt_history;
1345         while (i > 0)
1346                 free(n->history[--i]);
1347         free(n);
1348 }
1349
1350 /* state->flags is already checked to be nonzero */
1351 static void load_history(line_input_t *st_parm)
1352 {
1353         char *temp_h[MAX_HISTORY];
1354         char *line;
1355         FILE *fp;
1356         unsigned idx, i, line_len;
1357
1358         /* NB: do not trash old history if file can't be opened */
1359
1360         fp = fopen_for_read(st_parm->hist_file);
1361         if (fp) {
1362                 /* clean up old history */
1363                 for (idx = st_parm->cnt_history; idx > 0;) {
1364                         idx--;
1365                         free(st_parm->history[idx]);
1366                         st_parm->history[idx] = NULL;
1367                 }
1368
1369                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1370                 memset(temp_h, 0, sizeof(temp_h));
1371                 idx = 0;
1372                 st_parm->cnt_history_in_file = 0;
1373                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1374                         if (line[0] == '\0') {
1375                                 free(line);
1376                                 continue;
1377                         }
1378                         free(temp_h[idx]);
1379                         temp_h[idx] = line;
1380                         st_parm->cnt_history_in_file++;
1381                         idx++;
1382                         if (idx == st_parm->max_history)
1383                                 idx = 0;
1384                 }
1385                 fclose(fp);
1386
1387                 /* find first non-NULL temp_h[], if any */
1388                 if (st_parm->cnt_history_in_file) {
1389                         while (temp_h[idx] == NULL) {
1390                                 idx++;
1391                                 if (idx == st_parm->max_history)
1392                                         idx = 0;
1393                         }
1394                 }
1395
1396                 /* copy temp_h[] to st_parm->history[] */
1397                 for (i = 0; i < st_parm->max_history;) {
1398                         line = temp_h[idx];
1399                         if (!line)
1400                                 break;
1401                         idx++;
1402                         if (idx == st_parm->max_history)
1403                                 idx = 0;
1404                         line_len = strlen(line);
1405                         if (line_len >= MAX_LINELEN)
1406                                 line[MAX_LINELEN-1] = '\0';
1407                         st_parm->history[i++] = line;
1408                 }
1409                 st_parm->cnt_history = i;
1410                 if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
1411                         st_parm->cnt_history_in_file = i;
1412         }
1413 }
1414
1415 #  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1416 void save_history(line_input_t *st)
1417 {
1418         FILE *fp;
1419
1420         if (!st->hist_file)
1421                 return;
1422         if (st->cnt_history <= st->cnt_history_in_file)
1423                 return;
1424
1425         fp = fopen(st->hist_file, "a");
1426         if (fp) {
1427                 int i, fd;
1428                 char *new_name;
1429                 line_input_t *st_temp;
1430
1431                 for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
1432                         fprintf(fp, "%s\n", st->history[i]);
1433                 fclose(fp);
1434
1435                 /* we may have concurrently written entries from others.
1436                  * load them */
1437                 st_temp = new_line_input_t(st->flags);
1438                 st_temp->hist_file = st->hist_file;
1439                 st_temp->max_history = st->max_history;
1440                 load_history(st_temp);
1441
1442                 /* write out temp file and replace hist_file atomically */
1443                 new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
1444                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1445                 if (fd >= 0) {
1446                         fp = xfdopen_for_write(fd);
1447                         for (i = 0; i < st_temp->cnt_history; i++)
1448                                 fprintf(fp, "%s\n", st_temp->history[i]);
1449                         fclose(fp);
1450                         if (rename(new_name, st->hist_file) == 0)
1451                                 st->cnt_history_in_file = st_temp->cnt_history;
1452                 }
1453                 free(new_name);
1454                 free_line_input_t(st_temp);
1455         }
1456 }
1457 #  else
1458 static void save_history(char *str)
1459 {
1460         int fd;
1461         int len, len2;
1462
1463         if (!state->hist_file)
1464                 return;
1465
1466         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1467         if (fd < 0)
1468                 return;
1469         xlseek(fd, 0, SEEK_END); /* paranoia */
1470         len = strlen(str);
1471         str[len] = '\n'; /* we (try to) do atomic write */
1472         len2 = full_write(fd, str, len + 1);
1473         str[len] = '\0';
1474         close(fd);
1475         if (len2 != len + 1)
1476                 return; /* "wtf?" */
1477
1478         /* did we write so much that history file needs trimming? */
1479         state->cnt_history_in_file++;
1480         if (state->cnt_history_in_file > state->max_history * 4) {
1481                 char *new_name;
1482                 line_input_t *st_temp;
1483
1484                 /* we may have concurrently written entries from others.
1485                  * load them */
1486                 st_temp = new_line_input_t(state->flags);
1487                 st_temp->hist_file = state->hist_file;
1488                 st_temp->max_history = state->max_history;
1489                 load_history(st_temp);
1490
1491                 /* write out temp file and replace hist_file atomically */
1492                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1493                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1494                 if (fd >= 0) {
1495                         FILE *fp;
1496                         int i;
1497
1498                         fp = xfdopen_for_write(fd);
1499                         for (i = 0; i < st_temp->cnt_history; i++)
1500                                 fprintf(fp, "%s\n", st_temp->history[i]);
1501                         fclose(fp);
1502                         if (rename(new_name, state->hist_file) == 0)
1503                                 state->cnt_history_in_file = st_temp->cnt_history;
1504                 }
1505                 free(new_name);
1506                 free_line_input_t(st_temp);
1507         }
1508 }
1509 #  endif
1510 # else
1511 #  define load_history(a) ((void)0)
1512 #  define save_history(a) ((void)0)
1513 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1514
1515 static void remember_in_history(char *str)
1516 {
1517         int i;
1518
1519         if (!(state->flags & DO_HISTORY))
1520                 return;
1521         if (str[0] == '\0')
1522                 return;
1523         i = state->cnt_history;
1524         /* Don't save dupes */
1525         if (i && strcmp(state->history[i-1], str) == 0)
1526                 return;
1527
1528         free(state->history[state->max_history]); /* redundant, paranoia */
1529         state->history[state->max_history] = NULL; /* redundant, paranoia */
1530
1531         /* If history[] is full, remove the oldest command */
1532         /* we need to keep history[state->max_history] empty, hence >=, not > */
1533         if (i >= state->max_history) {
1534                 free(state->history[0]);
1535                 for (i = 0; i < state->max_history-1; i++)
1536                         state->history[i] = state->history[i+1];
1537                 /* i == state->max_history-1 */
1538 # if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1539                 if (state->cnt_history_in_file)
1540                         state->cnt_history_in_file--;
1541 # endif
1542         }
1543         /* i <= state->max_history-1 */
1544         state->history[i++] = xstrdup(str);
1545         /* i <= state->max_history */
1546         state->cur_history = i;
1547         state->cnt_history = i;
1548 # if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1549         save_history(str);
1550 # endif
1551 }
1552
1553 #else /* MAX_HISTORY == 0 */
1554 # define remember_in_history(a) ((void)0)
1555 #endif /* MAX_HISTORY */
1556
1557
1558 #if ENABLE_FEATURE_EDITING_VI
1559 /*
1560  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1561  */
1562 static void
1563 vi_Word_motion(int eat)
1564 {
1565         CHAR_T *command = command_ps;
1566
1567         while (cursor < command_len && !BB_isspace(command[cursor]))
1568                 input_forward();
1569         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1570                 input_forward();
1571 }
1572
1573 static void
1574 vi_word_motion(int eat)
1575 {
1576         CHAR_T *command = command_ps;
1577
1578         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1579                 while (cursor < command_len
1580                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1581                 ) {
1582                         input_forward();
1583                 }
1584         } else if (BB_ispunct(command[cursor])) {
1585                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1586                         input_forward();
1587         }
1588
1589         if (cursor < command_len)
1590                 input_forward();
1591
1592         if (eat) {
1593                 while (cursor < command_len && BB_isspace(command[cursor]))
1594                         input_forward();
1595         }
1596 }
1597
1598 static void
1599 vi_End_motion(void)
1600 {
1601         CHAR_T *command = command_ps;
1602
1603         input_forward();
1604         while (cursor < command_len && BB_isspace(command[cursor]))
1605                 input_forward();
1606         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1607                 input_forward();
1608 }
1609
1610 static void
1611 vi_end_motion(void)
1612 {
1613         CHAR_T *command = command_ps;
1614
1615         if (cursor >= command_len-1)
1616                 return;
1617         input_forward();
1618         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1619                 input_forward();
1620         if (cursor >= command_len-1)
1621                 return;
1622         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1623                 while (cursor < command_len-1
1624                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1625                 ) {
1626                         input_forward();
1627                 }
1628         } else if (BB_ispunct(command[cursor])) {
1629                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1630                         input_forward();
1631         }
1632 }
1633
1634 static void
1635 vi_Back_motion(void)
1636 {
1637         CHAR_T *command = command_ps;
1638
1639         while (cursor > 0 && BB_isspace(command[cursor-1]))
1640                 input_backward(1);
1641         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1642                 input_backward(1);
1643 }
1644
1645 static void
1646 vi_back_motion(void)
1647 {
1648         CHAR_T *command = command_ps;
1649
1650         if (cursor <= 0)
1651                 return;
1652         input_backward(1);
1653         while (cursor > 0 && BB_isspace(command[cursor]))
1654                 input_backward(1);
1655         if (cursor <= 0)
1656                 return;
1657         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1658                 while (cursor > 0
1659                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1660                 ) {
1661                         input_backward(1);
1662                 }
1663         } else if (BB_ispunct(command[cursor])) {
1664                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1665                         input_backward(1);
1666         }
1667 }
1668 #endif
1669
1670 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1671 static void ctrl_left(void)
1672 {
1673         CHAR_T *command = command_ps;
1674
1675         while (1) {
1676                 CHAR_T c;
1677
1678                 input_backward(1);
1679                 if (cursor == 0)
1680                         break;
1681                 c = command[cursor];
1682                 if (c != ' ' && !BB_ispunct(c)) {
1683                         /* we reached a "word" delimited by spaces/punct.
1684                          * go to its beginning */
1685                         while (1) {
1686                                 c = command[cursor - 1];
1687                                 if (c == ' ' || BB_ispunct(c))
1688                                         break;
1689                                 input_backward(1);
1690                                 if (cursor == 0)
1691                                         break;
1692                         }
1693                         break;
1694                 }
1695         }
1696 }
1697 static void ctrl_right(void)
1698 {
1699         CHAR_T *command = command_ps;
1700
1701         while (1) {
1702                 CHAR_T c;
1703
1704                 c = command[cursor];
1705                 if (c == BB_NUL)
1706                         break;
1707                 if (c != ' ' && !BB_ispunct(c)) {
1708                         /* we reached a "word" delimited by spaces/punct.
1709                          * go to its end + 1 */
1710                         while (1) {
1711                                 input_forward();
1712                                 c = command[cursor];
1713                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1714                                         break;
1715                         }
1716                         break;
1717                 }
1718                 input_forward();
1719         }
1720 }
1721
1722
1723 /*
1724  * read_line_input and its helpers
1725  */
1726
1727 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1728 static void ask_terminal(void)
1729 {
1730         /* Ask terminal where is the cursor now.
1731          * lineedit_read_key handles response and corrects
1732          * our idea of current cursor position.
1733          * Testcase: run "echo -n long_line_long_line_long_line",
1734          * then type in a long, wrapping command and try to
1735          * delete it using backspace key.
1736          * Note: we print it _after_ prompt, because
1737          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1738          */
1739         /* Problem: if there is buffered input on stdin,
1740          * the response will be delivered later,
1741          * possibly to an unsuspecting application.
1742          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1743          * Result:
1744          * ~/srcdevel/bbox/fix/busybox.t4 #
1745          * ~/srcdevel/bbox/fix/busybox.t4 #
1746          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1747          * ~/srcdevel/bbox/fix/busybox.t4 #
1748          *
1749          * Checking for input with poll only makes the race narrower,
1750          * I still can trigger it. Strace:
1751          *
1752          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1753          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1754          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1755          * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
1756          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1757          */
1758         struct pollfd pfd;
1759
1760         pfd.fd = STDIN_FILENO;
1761         pfd.events = POLLIN;
1762         if (safe_poll(&pfd, 1, 0) == 0) {
1763                 S.sent_ESC_br6n = 1;
1764                 fputs(ESC"[6n", stdout);
1765                 fflush_all(); /* make terminal see it ASAP! */
1766         }
1767 }
1768 #else
1769 #define ask_terminal() ((void)0)
1770 #endif
1771
1772 /* Called just once at read_line_input() init time */
1773 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1774 static void parse_and_put_prompt(const char *prmt_ptr)
1775 {
1776         const char *p;
1777         cmdedit_prompt = prmt_ptr;
1778         p = strrchr(prmt_ptr, '\n');
1779         cmdedit_prmt_len = unicode_strwidth(p ? p+1 : prmt_ptr);
1780         put_prompt();
1781 }
1782 #else
1783 static void parse_and_put_prompt(const char *prmt_ptr)
1784 {
1785         int prmt_size = 0;
1786         char *prmt_mem_ptr = xzalloc(1);
1787 # if ENABLE_USERNAME_OR_HOMEDIR
1788         char *cwd_buf = NULL;
1789 # endif
1790         char flg_not_length = '[';
1791         char cbuf[2];
1792
1793         /*cmdedit_prmt_len = 0; - already is */
1794
1795         cbuf[1] = '\0'; /* never changes */
1796
1797         while (*prmt_ptr) {
1798                 char timebuf[sizeof("HH:MM:SS")];
1799                 char *free_me = NULL;
1800                 char *pbuf;
1801                 char c;
1802
1803                 pbuf = cbuf;
1804                 c = *prmt_ptr++;
1805                 if (c == '\\') {
1806                         const char *cp;
1807                         int l;
1808 /*
1809  * Supported via bb_process_escape_sequence:
1810  * \a   ASCII bell character (07)
1811  * \e   ASCII escape character (033)
1812  * \n   newline
1813  * \r   carriage return
1814  * \\   backslash
1815  * \nnn char with octal code nnn
1816  * Supported:
1817  * \$   if the effective UID is 0, a #, otherwise a $
1818  * \w   current working directory, with $HOME abbreviated with a tilde
1819  *      Note: we do not support $PROMPT_DIRTRIM=n feature
1820  * \W   basename of the current working directory, with $HOME abbreviated with a tilde
1821  * \h   hostname up to the first '.'
1822  * \H   hostname
1823  * \u   username
1824  * \[   begin a sequence of non-printing characters
1825  * \]   end a sequence of non-printing characters
1826  * \T   current time in 12-hour HH:MM:SS format
1827  * \@   current time in 12-hour am/pm format
1828  * \A   current time in 24-hour HH:MM format
1829  * \t   current time in 24-hour HH:MM:SS format
1830  *      (all of the above work as \A)
1831  * Not supported:
1832  * \!   history number of this command
1833  * \#   command number of this command
1834  * \j   number of jobs currently managed by the shell
1835  * \l   basename of the shell's terminal device name
1836  * \s   name of the shell, the basename of $0 (the portion following the final slash)
1837  * \V   release of bash, version + patch level (e.g., 2.00.0)
1838  * \d   date in "Weekday Month Date" format (e.g., "Tue May 26")
1839  * \D{format}
1840  *      format is passed to strftime(3).
1841  *      An empty format results in a locale-specific time representation.
1842  *      The braces are required.
1843  * Mishandled by bb_process_escape_sequence:
1844  * \v   version of bash (e.g., 2.00)
1845  */
1846                         cp = prmt_ptr;
1847                         c = *cp;
1848                         if (c != 't') /* don't treat \t as tab */
1849                                 c = bb_process_escape_sequence(&prmt_ptr);
1850                         if (prmt_ptr == cp) {
1851                                 if (*cp == '\0')
1852                                         break;
1853                                 c = *prmt_ptr++;
1854
1855                                 switch (c) {
1856 # if ENABLE_USERNAME_OR_HOMEDIR
1857                                 case 'u':
1858                                         pbuf = user_buf ? user_buf : (char*)"";
1859                                         break;
1860 # endif
1861                                 case 'H':
1862                                 case 'h':
1863                                         pbuf = free_me = safe_gethostname();
1864                                         if (c == 'h')
1865                                                 strchrnul(pbuf, '.')[0] = '\0';
1866                                         break;
1867                                 case '$':
1868                                         c = (geteuid() == 0 ? '#' : '$');
1869                                         break;
1870                                 case 'T': /* 12-hour HH:MM:SS format */
1871                                 case '@': /* 12-hour am/pm format */
1872                                 case 'A': /* 24-hour HH:MM format */
1873                                 case 't': /* 24-hour HH:MM:SS format */
1874                                         /* We show all of them as 24-hour HH:MM */
1875                                         strftime_HHMMSS(timebuf, sizeof(timebuf), NULL)[-3] = '\0';
1876                                         pbuf = timebuf;
1877                                         break;
1878 # if ENABLE_USERNAME_OR_HOMEDIR
1879                                 case 'w': /* current dir */
1880                                 case 'W': /* basename of cur dir */
1881                                         if (!cwd_buf) {
1882                                                 cwd_buf = xrealloc_getcwd_or_warn(NULL);
1883                                                 if (!cwd_buf)
1884                                                         cwd_buf = (char *)bb_msg_unknown;
1885                                                 else {
1886                                                         /* /home/user[/something] -> ~[/something] */
1887                                                         l = strlen(home_pwd_buf);
1888                                                         if (l != 0
1889                                                          && strncmp(home_pwd_buf, cwd_buf, l) == 0
1890                                                          && (cwd_buf[l] == '/' || cwd_buf[l] == '\0')
1891                                                         ) {
1892                                                                 cwd_buf[0] = '~';
1893                                                                 overlapping_strcpy(cwd_buf + 1, cwd_buf + l);
1894                                                         }
1895                                                 }
1896                                         }
1897                                         pbuf = cwd_buf;
1898                                         if (c == 'w')
1899                                                 break;
1900                                         cp = strrchr(pbuf, '/');
1901                                         if (cp)
1902                                                 pbuf = (char*)cp + 1;
1903                                         break;
1904 # endif
1905 // bb_process_escape_sequence does this now:
1906 //                              case 'e': case 'E':     /* \e \E = \033 */
1907 //                                      c = '\033';
1908 //                                      break;
1909                                 case 'x': case 'X': {
1910                                         char buf2[4];
1911                                         for (l = 0; l < 3;) {
1912                                                 unsigned h;
1913                                                 buf2[l++] = *prmt_ptr;
1914                                                 buf2[l] = '\0';
1915                                                 h = strtoul(buf2, &pbuf, 16);
1916                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1917                                                         buf2[--l] = '\0';
1918                                                         break;
1919                                                 }
1920                                                 prmt_ptr++;
1921                                         }
1922                                         c = (char)strtoul(buf2, NULL, 16);
1923                                         if (c == 0)
1924                                                 c = '?';
1925                                         pbuf = cbuf;
1926                                         break;
1927                                 }
1928                                 case '[': case ']':
1929                                         if (c == flg_not_length) {
1930                                                 /* Toggle '['/']' hex 5b/5d */
1931                                                 flg_not_length ^= 6;
1932                                                 continue;
1933                                         }
1934                                         break;
1935                                 } /* switch */
1936                         } /* if */
1937                 } /* if */
1938                 cbuf[0] = c;
1939                 {
1940                         int n = strlen(pbuf);
1941                         prmt_size += n;
1942                         if (c == '\n')
1943                                 cmdedit_prmt_len = 0;
1944                         else if (flg_not_length != ']') {
1945 #if 0 /*ENABLE_UNICODE_SUPPORT*/
1946 /* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
1947 /* FIXME */
1948                                 cmdedit_prmt_len += unicode_strwidth(pbuf);
1949 #else
1950                                 cmdedit_prmt_len += n;
1951 #endif
1952                         }
1953                 }
1954                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_size+1), pbuf);
1955                 free(free_me);
1956         } /* while */
1957
1958 # if ENABLE_USERNAME_OR_HOMEDIR
1959         if (cwd_buf != (char *)bb_msg_unknown)
1960                 free(cwd_buf);
1961 # endif
1962         cmdedit_prompt = prmt_mem_ptr;
1963         put_prompt();
1964 }
1965 #endif
1966
1967 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1968 {
1969         cmdedit_termw = w;
1970         if (redraw_flg) {
1971                 /* new y for current cursor */
1972                 int new_y = (cursor + cmdedit_prmt_len) / w;
1973                 /* redraw */
1974                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1975                 fflush_all();
1976         }
1977 }
1978
1979 static void win_changed(int nsig)
1980 {
1981         int sv_errno = errno;
1982         unsigned width;
1983
1984         get_terminal_width_height(0, &width, NULL);
1985 //FIXME: cmdedit_setwidth() -> redraw() -> printf() -> KABOOM! (we are in signal handler!)
1986         cmdedit_setwidth(width, /*redraw_flg:*/ nsig);
1987
1988         errno = sv_errno;
1989 }
1990
1991 static int lineedit_read_key(char *read_key_buffer, int timeout)
1992 {
1993         int64_t ic;
1994 #if ENABLE_UNICODE_SUPPORT
1995         char unicode_buf[MB_CUR_MAX + 1];
1996         int unicode_idx = 0;
1997 #endif
1998
1999         while (1) {
2000                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
2001                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
2002                  * insist on full MB_CUR_MAX buffer to declare input like
2003                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
2004                  *
2005                  * Note: read_key sets errno to 0 on success.
2006                  */
2007                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
2008                 if (errno) {
2009 #if ENABLE_UNICODE_SUPPORT
2010                         if (errno == EAGAIN && unicode_idx != 0)
2011                                 goto pushback;
2012 #endif
2013                         break;
2014                 }
2015
2016 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2017                 if ((int32_t)ic == KEYCODE_CURSOR_POS
2018                  && S.sent_ESC_br6n
2019                 ) {
2020                         S.sent_ESC_br6n = 0;
2021                         if (cursor == 0) { /* otherwise it may be bogus */
2022                                 int col = ((ic >> 32) & 0x7fff) - 1;
2023                                 /*
2024                                  * Is col > cmdedit_prmt_len?
2025                                  * If yes (terminal says cursor is farther to the right
2026                                  * of where we think it should be),
2027                                  * the prompt wasn't printed starting at col 1,
2028                                  * there was additional text before it.
2029                                  */
2030                                 if ((int)(col - cmdedit_prmt_len) > 0) {
2031                                         /* Fix our understanding of current x position */
2032                                         cmdedit_x += (col - cmdedit_prmt_len);
2033                                         while (cmdedit_x >= cmdedit_termw) {
2034                                                 cmdedit_x -= cmdedit_termw;
2035                                                 cmdedit_y++;
2036                                         }
2037                                 }
2038                         }
2039                         continue;
2040                 }
2041 #endif
2042
2043 #if ENABLE_UNICODE_SUPPORT
2044                 if (unicode_status == UNICODE_ON) {
2045                         wchar_t wc;
2046
2047                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
2048                                 break;
2049                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
2050
2051                         unicode_buf[unicode_idx++] = ic;
2052                         unicode_buf[unicode_idx] = '\0';
2053                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
2054                                 /* Not (yet?) a valid unicode char */
2055                                 if (unicode_idx < MB_CUR_MAX) {
2056                                         timeout = 50;
2057                                         continue;
2058                                 }
2059  pushback:
2060                                 /* Invalid sequence. Save all "bad bytes" except first */
2061                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
2062 # if !ENABLE_UNICODE_PRESERVE_BROKEN
2063                                 ic = CONFIG_SUBST_WCHAR;
2064 # else
2065                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
2066 # endif
2067                         } else {
2068                                 /* Valid unicode char, return its code */
2069                                 ic = wc;
2070                         }
2071                 }
2072 #endif
2073                 break;
2074         }
2075
2076         return ic;
2077 }
2078
2079 #if ENABLE_UNICODE_BIDI_SUPPORT
2080 static int isrtl_str(void)
2081 {
2082         int idx = cursor;
2083
2084         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
2085                 idx++;
2086         return unicode_bidi_isrtl(command_ps[idx]);
2087 }
2088 #else
2089 # define isrtl_str() 0
2090 #endif
2091
2092 /* leave out the "vi-mode"-only case labels if vi editing isn't
2093  * configured. */
2094 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
2095
2096 /* convert uppercase ascii to equivalent control char, for readability */
2097 #undef CTRL
2098 #define CTRL(a) ((a) & ~0x40)
2099
2100 enum {
2101         VI_CMDMODE_BIT = 0x40000000,
2102         /* 0x80000000 bit flags KEYCODE_xxx */
2103 };
2104
2105 #if ENABLE_FEATURE_REVERSE_SEARCH
2106 /* Mimic readline Ctrl-R reverse history search.
2107  * When invoked, it shows the following prompt:
2108  * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
2109  * and typing results in search being performed:
2110  * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
2111  * Search is performed by looking at progressively older lines in history.
2112  * Ctrl-R again searches for the next match in history.
2113  * Backspace deletes last matched char.
2114  * Control keys exit search and return to normal editing (at current history line).
2115  */
2116 static int32_t reverse_i_search(void)
2117 {
2118         char match_buf[128]; /* for user input */
2119         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2120         const char *matched_history_line;
2121         const char *saved_prompt;
2122         unsigned saved_prmt_len;
2123         int32_t ic;
2124
2125         matched_history_line = NULL;
2126         read_key_buffer[0] = 0;
2127         match_buf[0] = '\0';
2128
2129         /* Save and replace the prompt */
2130         saved_prompt = cmdedit_prompt;
2131         saved_prmt_len = cmdedit_prmt_len;
2132         goto set_prompt;
2133
2134         while (1) {
2135                 int h;
2136                 unsigned match_buf_len = strlen(match_buf);
2137
2138                 fflush_all();
2139 //FIXME: correct timeout?
2140                 ic = lineedit_read_key(read_key_buffer, -1);
2141
2142                 switch (ic) {
2143                 case CTRL('R'): /* searching for the next match */
2144                         break;
2145
2146                 case '\b':
2147                 case '\x7f':
2148                         /* Backspace */
2149                         if (unicode_status == UNICODE_ON) {
2150                                 while (match_buf_len != 0) {
2151                                         uint8_t c = match_buf[--match_buf_len];
2152                                         if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
2153                                                 break; /* yes */
2154                                 }
2155                         } else {
2156                                 if (match_buf_len != 0)
2157                                         match_buf_len--;
2158                         }
2159                         match_buf[match_buf_len] = '\0';
2160                         break;
2161
2162                 default:
2163                         if (ic < ' '
2164                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2165                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2166                         ) {
2167                                 goto ret;
2168                         }
2169
2170                         /* Append this char */
2171 #if ENABLE_UNICODE_SUPPORT
2172                         if (unicode_status == UNICODE_ON) {
2173                                 mbstate_t mbstate = { 0 };
2174                                 char buf[MB_CUR_MAX + 1];
2175                                 int len = wcrtomb(buf, ic, &mbstate);
2176                                 if (len > 0) {
2177                                         buf[len] = '\0';
2178                                         if (match_buf_len + len < sizeof(match_buf))
2179                                                 strcpy(match_buf + match_buf_len, buf);
2180                                 }
2181                         } else
2182 #endif
2183                         if (match_buf_len < sizeof(match_buf) - 1) {
2184                                 match_buf[match_buf_len] = ic;
2185                                 match_buf[match_buf_len + 1] = '\0';
2186                         }
2187                         break;
2188                 } /* switch (ic) */
2189
2190                 /* Search in history for match_buf */
2191                 h = state->cur_history;
2192                 if (ic == CTRL('R'))
2193                         h--;
2194                 while (h >= 0) {
2195                         if (state->history[h]) {
2196                                 char *match = strstr(state->history[h], match_buf);
2197                                 if (match) {
2198                                         state->cur_history = h;
2199                                         matched_history_line = state->history[h];
2200                                         command_len = load_string(matched_history_line);
2201                                         cursor = match - matched_history_line;
2202 //FIXME: cursor position for Unicode case
2203
2204                                         free((char*)cmdedit_prompt);
2205  set_prompt:
2206                                         cmdedit_prompt = xasprintf("(reverse-i-search)'%s': ", match_buf);
2207                                         cmdedit_prmt_len = unicode_strwidth(cmdedit_prompt);
2208                                         goto do_redraw;
2209                                 }
2210                         }
2211                         h--;
2212                 }
2213
2214                 /* Not found */
2215                 match_buf[match_buf_len] = '\0';
2216                 beep();
2217                 continue;
2218
2219  do_redraw:
2220                 redraw(cmdedit_y, command_len - cursor);
2221         } /* while (1) */
2222
2223  ret:
2224         if (matched_history_line)
2225                 command_len = load_string(matched_history_line);
2226
2227         free((char*)cmdedit_prompt);
2228         cmdedit_prompt = saved_prompt;
2229         cmdedit_prmt_len = saved_prmt_len;
2230         redraw(cmdedit_y, command_len - cursor);
2231
2232         return ic;
2233 }
2234 #endif
2235
2236 /* maxsize must be >= 2.
2237  * Returns:
2238  * -1 on read errors or EOF, or on bare Ctrl-D,
2239  * 0  on ctrl-C (the line entered is still returned in 'command'),
2240  * >0 length of input string, including terminating '\n'
2241  */
2242 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize, int timeout)
2243 {
2244         int len;
2245 #if ENABLE_FEATURE_TAB_COMPLETION
2246         smallint lastWasTab = 0;
2247 #endif
2248         smallint break_out = 0;
2249 #if ENABLE_FEATURE_EDITING_VI
2250         smallint vi_cmdmode = 0;
2251 #endif
2252         struct termios initial_settings;
2253         struct termios new_settings;
2254         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2255
2256         INIT_S();
2257
2258         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
2259          || !(initial_settings.c_lflag & ECHO)
2260         ) {
2261                 /* Happens when e.g. stty -echo was run before */
2262                 parse_and_put_prompt(prompt);
2263                 /* fflush_all(); - done by parse_and_put_prompt */
2264                 if (fgets(command, maxsize, stdin) == NULL)
2265                         len = -1; /* EOF or error */
2266                 else
2267                         len = strlen(command);
2268                 DEINIT_S();
2269                 return len;
2270         }
2271
2272         init_unicode();
2273
2274 // FIXME: audit & improve this
2275         if (maxsize > MAX_LINELEN)
2276                 maxsize = MAX_LINELEN;
2277         S.maxsize = maxsize;
2278
2279         /* With zero flags, no other fields are ever used */
2280         state = st ? st : (line_input_t*) &const_int_0;
2281 #if MAX_HISTORY > 0
2282 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
2283         if (state->hist_file)
2284                 if (state->cnt_history == 0)
2285                         load_history(state);
2286 # endif
2287         if (state->flags & DO_HISTORY)
2288                 state->cur_history = state->cnt_history;
2289 #endif
2290
2291         /* prepare before init handlers */
2292         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
2293         command_len = 0;
2294 #if ENABLE_UNICODE_SUPPORT
2295         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
2296 #else
2297         command_ps = command;
2298         command[0] = '\0';
2299 #endif
2300 #define command command_must_not_be_used
2301
2302         new_settings = initial_settings;
2303         /* ~ICANON: unbuffered input (most c_cc[] are disabled, VMIN/VTIME are enabled) */
2304         /* ~ECHO, ~ECHONL: turn off echoing, including newline echoing */
2305         /* ~ISIG: turn off INTR (ctrl-C), QUIT, SUSP */
2306         new_settings.c_lflag &= ~(ICANON | ECHO | ECHONL | ISIG);
2307         /* reads would block only if < 1 char is available */
2308         new_settings.c_cc[VMIN] = 1;
2309         /* no timeout (reads block forever) */
2310         new_settings.c_cc[VTIME] = 0;
2311         /* Should be not needed if ISIG is off: */
2312         /* Turn off CTRL-C */
2313         /* new_settings.c_cc[VINTR] = _POSIX_VDISABLE; */
2314         tcsetattr_stdin_TCSANOW(&new_settings);
2315
2316 #if ENABLE_USERNAME_OR_HOMEDIR
2317         {
2318                 struct passwd *entry;
2319
2320                 entry = getpwuid(geteuid());
2321                 if (entry) {
2322                         user_buf = xstrdup(entry->pw_name);
2323                         home_pwd_buf = xstrdup(entry->pw_dir);
2324                 }
2325         }
2326 #endif
2327
2328 #if 0
2329         for (i = 0; i <= state->max_history; i++)
2330                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2331         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2332 #endif
2333
2334         /* Print out the command prompt, optionally ask where cursor is */
2335         parse_and_put_prompt(prompt);
2336         ask_terminal();
2337
2338         /* Install window resize handler (NB: after *all* init is complete) */
2339 //FIXME: save entire sigaction!
2340         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
2341         win_changed(0); /* get initial window size */
2342
2343         read_key_buffer[0] = 0;
2344         while (1) {
2345                 /*
2346                  * The emacs and vi modes share much of the code in the big
2347                  * command loop.  Commands entered when in vi's command mode
2348                  * (aka "escape mode") get an extra bit added to distinguish
2349                  * them - this keeps them from being self-inserted. This
2350                  * clutters the big switch a bit, but keeps all the code
2351                  * in one place.
2352                  */
2353                 int32_t ic, ic_raw;
2354
2355                 fflush_all();
2356                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2357
2358 #if ENABLE_FEATURE_REVERSE_SEARCH
2359  again:
2360 #endif
2361 #if ENABLE_FEATURE_EDITING_VI
2362                 newdelflag = 1;
2363                 if (vi_cmdmode) {
2364                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2365                          * change ic if it contains one of them: */
2366                         ic |= VI_CMDMODE_BIT;
2367                 }
2368 #endif
2369
2370                 switch (ic) {
2371                 case '\n':
2372                 case '\r':
2373                 vi_case('\n'|VI_CMDMODE_BIT:)
2374                 vi_case('\r'|VI_CMDMODE_BIT:)
2375                         /* Enter */
2376                         goto_new_line();
2377                         break_out = 1;
2378                         break;
2379                 case CTRL('A'):
2380                 vi_case('0'|VI_CMDMODE_BIT:)
2381                         /* Control-a -- Beginning of line */
2382                         input_backward(cursor);
2383                         break;
2384                 case CTRL('B'):
2385                 vi_case('h'|VI_CMDMODE_BIT:)
2386                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2387                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2388                         input_backward(1); /* Move back one character */
2389                         break;
2390                 case CTRL('E'):
2391                 vi_case('$'|VI_CMDMODE_BIT:)
2392                         /* Control-e -- End of line */
2393                         put_till_end_and_adv_cursor();
2394                         break;
2395                 case CTRL('F'):
2396                 vi_case('l'|VI_CMDMODE_BIT:)
2397                 vi_case(' '|VI_CMDMODE_BIT:)
2398                         input_forward(); /* Move forward one character */
2399                         break;
2400                 case '\b':   /* ^H */
2401                 case '\x7f': /* DEL */
2402                         if (!isrtl_str())
2403                                 input_backspace();
2404                         else
2405                                 input_delete(0);
2406                         break;
2407                 case KEYCODE_DELETE:
2408                         if (!isrtl_str())
2409                                 input_delete(0);
2410                         else
2411                                 input_backspace();
2412                         break;
2413 #if ENABLE_FEATURE_TAB_COMPLETION
2414                 case '\t':
2415                         input_tab(&lastWasTab);
2416                         break;
2417 #endif
2418                 case CTRL('K'):
2419                         /* Control-k -- clear to end of line */
2420                         command_ps[cursor] = BB_NUL;
2421                         command_len = cursor;
2422                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2423                         break;
2424                 case CTRL('L'):
2425                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2426                         /* Control-l -- clear screen */
2427                         printf(ESC"[H"); /* cursor to top,left */
2428                         redraw(0, command_len - cursor);
2429                         break;
2430 #if MAX_HISTORY > 0
2431                 case CTRL('N'):
2432                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2433                 vi_case('j'|VI_CMDMODE_BIT:)
2434                         /* Control-n -- Get next command in history */
2435                         if (get_next_history())
2436                                 goto rewrite_line;
2437                         break;
2438                 case CTRL('P'):
2439                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2440                 vi_case('k'|VI_CMDMODE_BIT:)
2441                         /* Control-p -- Get previous command from history */
2442                         if (get_previous_history())
2443                                 goto rewrite_line;
2444                         break;
2445 #endif
2446                 case CTRL('U'):
2447                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2448                         /* Control-U -- Clear line before cursor */
2449                         if (cursor) {
2450                                 command_len -= cursor;
2451                                 memmove(command_ps, command_ps + cursor,
2452                                         (command_len + 1) * sizeof(command_ps[0]));
2453                                 redraw(cmdedit_y, command_len);
2454                         }
2455                         break;
2456                 case CTRL('W'):
2457                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2458                         /* Control-W -- Remove the last word */
2459                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2460                                 input_backspace();
2461                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2462                                 input_backspace();
2463                         break;
2464 #if ENABLE_FEATURE_REVERSE_SEARCH
2465                 case CTRL('R'):
2466                         ic = ic_raw = reverse_i_search();
2467                         goto again;
2468 #endif
2469
2470 #if ENABLE_FEATURE_EDITING_VI
2471                 case 'i'|VI_CMDMODE_BIT:
2472                         vi_cmdmode = 0;
2473                         break;
2474                 case 'I'|VI_CMDMODE_BIT:
2475                         input_backward(cursor);
2476                         vi_cmdmode = 0;
2477                         break;
2478                 case 'a'|VI_CMDMODE_BIT:
2479                         input_forward();
2480                         vi_cmdmode = 0;
2481                         break;
2482                 case 'A'|VI_CMDMODE_BIT:
2483                         put_till_end_and_adv_cursor();
2484                         vi_cmdmode = 0;
2485                         break;
2486                 case 'x'|VI_CMDMODE_BIT:
2487                         input_delete(1);
2488                         break;
2489                 case 'X'|VI_CMDMODE_BIT:
2490                         if (cursor > 0) {
2491                                 input_backward(1);
2492                                 input_delete(1);
2493                         }
2494                         break;
2495                 case 'W'|VI_CMDMODE_BIT:
2496                         vi_Word_motion(1);
2497                         break;
2498                 case 'w'|VI_CMDMODE_BIT:
2499                         vi_word_motion(1);
2500                         break;
2501                 case 'E'|VI_CMDMODE_BIT:
2502                         vi_End_motion();
2503                         break;
2504                 case 'e'|VI_CMDMODE_BIT:
2505                         vi_end_motion();
2506                         break;
2507                 case 'B'|VI_CMDMODE_BIT:
2508                         vi_Back_motion();
2509                         break;
2510                 case 'b'|VI_CMDMODE_BIT:
2511                         vi_back_motion();
2512                         break;
2513                 case 'C'|VI_CMDMODE_BIT:
2514                         vi_cmdmode = 0;
2515                         /* fall through */
2516                 case 'D'|VI_CMDMODE_BIT:
2517                         goto clear_to_eol;
2518
2519                 case 'c'|VI_CMDMODE_BIT:
2520                         vi_cmdmode = 0;
2521                         /* fall through */
2522                 case 'd'|VI_CMDMODE_BIT: {
2523                         int nc, sc;
2524
2525                         ic = lineedit_read_key(read_key_buffer, timeout);
2526                         if (errno) /* error */
2527                                 goto return_error_indicator;
2528                         if (ic == ic_raw) { /* "cc", "dd" */
2529                                 input_backward(cursor);
2530                                 goto clear_to_eol;
2531                                 break;
2532                         }
2533
2534                         sc = cursor;
2535                         switch (ic) {
2536                         case 'w':
2537                         case 'W':
2538                         case 'e':
2539                         case 'E':
2540                                 switch (ic) {
2541                                 case 'w':   /* "dw", "cw" */
2542                                         vi_word_motion(vi_cmdmode);
2543                                         break;
2544                                 case 'W':   /* 'dW', 'cW' */
2545                                         vi_Word_motion(vi_cmdmode);
2546                                         break;
2547                                 case 'e':   /* 'de', 'ce' */
2548                                         vi_end_motion();
2549                                         input_forward();
2550                                         break;
2551                                 case 'E':   /* 'dE', 'cE' */
2552                                         vi_End_motion();
2553                                         input_forward();
2554                                         break;
2555                                 }
2556                                 nc = cursor;
2557                                 input_backward(cursor - sc);
2558                                 while (nc-- > cursor)
2559                                         input_delete(1);
2560                                 break;
2561                         case 'b':  /* "db", "cb" */
2562                         case 'B':  /* implemented as B */
2563                                 if (ic == 'b')
2564                                         vi_back_motion();
2565                                 else
2566                                         vi_Back_motion();
2567                                 while (sc-- > cursor)
2568                                         input_delete(1);
2569                                 break;
2570                         case ' ':  /* "d ", "c " */
2571                                 input_delete(1);
2572                                 break;
2573                         case '$':  /* "d$", "c$" */
2574  clear_to_eol:
2575                                 while (cursor < command_len)
2576                                         input_delete(1);
2577                                 break;
2578                         }
2579                         break;
2580                 }
2581                 case 'p'|VI_CMDMODE_BIT:
2582                         input_forward();
2583                         /* fallthrough */
2584                 case 'P'|VI_CMDMODE_BIT:
2585                         put();
2586                         break;
2587                 case 'r'|VI_CMDMODE_BIT:
2588 //FIXME: unicode case?
2589                         ic = lineedit_read_key(read_key_buffer, timeout);
2590                         if (errno) /* error */
2591                                 goto return_error_indicator;
2592                         if (ic < ' ' || ic > 255) {
2593                                 beep();
2594                         } else {
2595                                 command_ps[cursor] = ic;
2596                                 bb_putchar(ic);
2597                                 bb_putchar('\b');
2598                         }
2599                         break;
2600                 case '\x1b': /* ESC */
2601                         if (state->flags & VI_MODE) {
2602                                 /* insert mode --> command mode */
2603                                 vi_cmdmode = 1;
2604                                 input_backward(1);
2605                         }
2606                         /* Handle a few ESC-<key> combinations the same way
2607                          * standard readline bindings (IOW: bash) do.
2608                          * Often, Alt-<key> generates ESC-<key>.
2609                          */
2610                         ic = lineedit_read_key(read_key_buffer, timeout);
2611                         switch (ic) {
2612                                 //case KEYCODE_LEFT: - bash doesn't do this
2613                                 case 'b':
2614                                         ctrl_left();
2615                                         break;
2616                                 //case KEYCODE_RIGHT: - bash doesn't do this
2617                                 case 'f':
2618                                         ctrl_right();
2619                                         break;
2620                                 //case KEYCODE_DELETE: - bash doesn't do this
2621                                 case 'd':  /* Alt-D */
2622                                 {
2623                                         /* Delete word forward */
2624                                         int nc, sc = cursor;
2625                                         ctrl_right();
2626                                         nc = cursor - sc;
2627                                         input_backward(nc);
2628                                         while (--nc >= 0)
2629                                                 input_delete(1);
2630                                         break;
2631                                 }
2632                                 case '\b':   /* Alt-Backspace(?) */
2633                                 case '\x7f': /* Alt-Backspace(?) */
2634                                 //case 'w': - bash doesn't do this
2635                                 {
2636                                         /* Delete word backward */
2637                                         int sc = cursor;
2638                                         ctrl_left();
2639                                         while (sc-- > cursor)
2640                                                 input_delete(1);
2641                                         break;
2642                                 }
2643                         }
2644                         break;
2645 #endif /* FEATURE_COMMAND_EDITING_VI */
2646
2647 #if MAX_HISTORY > 0
2648                 case KEYCODE_UP:
2649                         if (get_previous_history())
2650                                 goto rewrite_line;
2651                         beep();
2652                         break;
2653                 case KEYCODE_DOWN:
2654                         if (!get_next_history())
2655                                 break;
2656  rewrite_line:
2657                         /* Rewrite the line with the selected history item */
2658                         /* change command */
2659                         command_len = load_string(state->history[state->cur_history] ?
2660                                         state->history[state->cur_history] : "");
2661                         /* redraw and go to eol (bol, in vi) */
2662                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2663                         break;
2664 #endif
2665                 case KEYCODE_RIGHT:
2666                         input_forward();
2667                         break;
2668                 case KEYCODE_LEFT:
2669                         input_backward(1);
2670                         break;
2671                 case KEYCODE_CTRL_LEFT:
2672                 case KEYCODE_ALT_LEFT: /* bash doesn't do it */
2673                         ctrl_left();
2674                         break;
2675                 case KEYCODE_CTRL_RIGHT:
2676                 case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
2677                         ctrl_right();
2678                         break;
2679                 case KEYCODE_HOME:
2680                         input_backward(cursor);
2681                         break;
2682                 case KEYCODE_END:
2683                         put_till_end_and_adv_cursor();
2684                         break;
2685
2686                 default:
2687                         if (initial_settings.c_cc[VINTR] != 0
2688                          && ic_raw == initial_settings.c_cc[VINTR]
2689                         ) {
2690                                 /* Ctrl-C (usually) - stop gathering input */
2691                                 goto_new_line();
2692                                 command_len = 0;
2693                                 break_out = -1; /* "do not append '\n'" */
2694                                 break;
2695                         }
2696                         if (initial_settings.c_cc[VEOF] != 0
2697                          && ic_raw == initial_settings.c_cc[VEOF]
2698                         ) {
2699                                 /* Ctrl-D (usually) - delete one character,
2700                                  * or exit if len=0 and no chars to delete */
2701                                 if (command_len == 0) {
2702                                         errno = 0;
2703
2704                 case -1: /* error (e.g. EIO when tty is destroyed) */
2705  IF_FEATURE_EDITING_VI(return_error_indicator:)
2706                                         break_out = command_len = -1;
2707                                         break;
2708                                 }
2709                                 input_delete(0);
2710                                 break;
2711                         }
2712 //                      /* Control-V -- force insert of next char */
2713 //                      if (c == CTRL('V')) {
2714 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2715 //                                      goto return_error_indicator;
2716 //                              if (c == 0) {
2717 //                                      beep();
2718 //                                      break;
2719 //                              }
2720 //                      }
2721                         if (ic < ' '
2722                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2723                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2724                         ) {
2725                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2726                                  * and vi mode ignores unexpected chars.
2727                                  * Otherwise, we are here if ic is a
2728                                  * control char or an unhandled ESC sequence,
2729                                  * which is also ignored.
2730                                  */
2731                                 break;
2732                         }
2733                         if ((int)command_len >= (maxsize - 2)) {
2734                                 /* Not enough space for the char and EOL */
2735                                 break;
2736                         }
2737
2738                         command_len++;
2739                         if (cursor == (command_len - 1)) {
2740                                 /* We are at the end, append */
2741                                 command_ps[cursor] = ic;
2742                                 command_ps[cursor + 1] = BB_NUL;
2743                                 put_cur_glyph_and_inc_cursor();
2744                                 if (unicode_bidi_isrtl(ic))
2745                                         input_backward(1);
2746                         } else {
2747                                 /* In the middle, insert */
2748                                 int sc = cursor;
2749
2750                                 memmove(command_ps + sc + 1, command_ps + sc,
2751                                         (command_len - sc) * sizeof(command_ps[0]));
2752                                 command_ps[sc] = ic;
2753                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2754                                 if (!isrtl_str())
2755                                         sc++; /* no */
2756                                 put_till_end_and_adv_cursor();
2757                                 /* to prev x pos + 1 */
2758                                 input_backward(cursor - sc);
2759                         }
2760                         break;
2761                 } /* switch (ic) */
2762
2763                 if (break_out)
2764                         break;
2765
2766 #if ENABLE_FEATURE_TAB_COMPLETION
2767                 if (ic_raw != '\t')
2768                         lastWasTab = 0;
2769 #endif
2770         } /* while (1) */
2771
2772 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2773         if (S.sent_ESC_br6n) {
2774                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2775                  * We sent "ESC [ 6 n", but got '\n' first, and
2776                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2777                  * It's bad already and not much can be done with it
2778                  * (it _will_ be visible for the next process to read stdin),
2779                  * but without this delay it even shows up on the screen
2780                  * as garbage because we restore echo settings with tcsetattr
2781                  * before it comes in. UGLY!
2782                  */
2783                 usleep(20*1000);
2784         }
2785 #endif
2786
2787 /* End of bug-catching "command_must_not_be_used" trick */
2788 #undef command
2789
2790 #if ENABLE_UNICODE_SUPPORT
2791         command[0] = '\0';
2792         if (command_len > 0)
2793                 command_len = save_string(command, maxsize - 1);
2794         free(command_ps);
2795 #endif
2796
2797         if (command_len > 0) {
2798                 remember_in_history(command);
2799         }
2800
2801         if (break_out > 0) {
2802                 command[command_len++] = '\n';
2803                 command[command_len] = '\0';
2804         }
2805
2806 #if ENABLE_FEATURE_TAB_COMPLETION
2807         free_tab_completion_data();
2808 #endif
2809
2810         /* restore initial_settings */
2811         tcsetattr_stdin_TCSANOW(&initial_settings);
2812         /* restore SIGWINCH handler */
2813         signal(SIGWINCH, previous_SIGWINCH_handler);
2814         fflush_all();
2815
2816         len = command_len;
2817         DEINIT_S();
2818
2819         return len; /* can't return command_len, DEINIT_S() destroys it */
2820 }
2821
2822 #else  /* !FEATURE_EDITING */
2823
2824 #undef read_line_input
2825 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2826 {
2827         fputs(prompt, stdout);
2828         fflush_all();
2829         if (!fgets(command, maxsize, stdin))
2830                 return -1;
2831         return strlen(command);
2832 }
2833
2834 #endif  /* !FEATURE_EDITING */
2835
2836
2837 /*
2838  * Testing
2839  */
2840
2841 #ifdef TEST
2842
2843 #include <locale.h>
2844
2845 const char *applet_name = "debug stuff usage";
2846
2847 int main(int argc, char **argv)
2848 {
2849         char buff[MAX_LINELEN];
2850         char *prompt =
2851 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2852                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2853                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2854                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2855 #else
2856                 "% ";
2857 #endif
2858
2859         while (1) {
2860                 int l;
2861                 l = read_line_input(prompt, buff);
2862                 if (l <= 0 || buff[l-1] != '\n')
2863                         break;
2864                 buff[l-1] = '\0';
2865                 printf("*** read_line_input() returned line =%s=\n", buff);
2866         }
2867         printf("*** read_line_input() detect ^D\n");
2868         return 0;
2869 }
2870
2871 #endif  /* TEST */