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  * Usage and known bugs:
  18  * Terminal key codes are not extensive, more needs to be added.
  19  * This version was created on Debian GNU/Linux 2.x.
  20  * Delete, Backspace, Home, End, and the arrow keys were tested
  21  * to work in an Xterm and console. Ctrl-A also works as Home.
  22  * Ctrl-E also works as End.
  23  *
  24  * The following readline-like commands are not implemented:
  25  * CTL-t -- Transpose two characters
  26  *
  27  * lineedit does not know that the terminal escape sequences do not
  28  * take up space on the screen. The redisplay code assumes, unless
  29  * told otherwise, that each character in the prompt is a printable
  30  * character that takes up one character position on the screen.
  31  * You need to tell lineedit that some sequences of characters
  32  * in the prompt take up no screen space. Compatibly with readline,
  33  * use the \[ escape to begin a sequence of non-printing characters,
  34  * and the \] escape to signal the end of such a sequence. Example:
  35  *
  36  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  37  *
  38  * Unicode in PS1 is not fully supported: prompt length calulation is wrong,
  39  * resulting in line wrap problems with long (multi-line) input.
  40  *
  41  * Multi-line PS1 (e.g. PS1="\n[\w]\n$ ") has problems with history
  42  * browsing: up/down arrows result in scrolling.
  43  * It stems from simplistic "cmdedit_y = cmdedit_prmt_len / cmdedit_termw"
  44  * calculation of how many lines the prompt takes.
  45  */
  46 #include "busybox.h"
  47 #include "NUM_APPLETS.h"
  48 #include "unicode.h"
  49 #ifndef _POSIX_VDISABLE
  50 # define _POSIX_VDISABLE '\0'
  51 #endif
  52
  53
  54 #ifdef TEST
  55 # define ENABLE_FEATURE_EDITING 0
  56 # define ENABLE_FEATURE_TAB_COMPLETION 0
  57 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  58 #endif
  59
  60
  61 /* Entire file (except TESTing part) sits inside this #if */
  62 #if ENABLE_FEATURE_EDITING
  63
  64
  65 #define ENABLE_USERNAME_OR_HOMEDIR \
  66         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  67 #define IF_USERNAME_OR_HOMEDIR(...)
  68 #if ENABLE_USERNAME_OR_HOMEDIR
  69 # undef IF_USERNAME_OR_HOMEDIR
  70 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  71 #endif
  72
  73
  74 #undef CHAR_T
  75 #if ENABLE_UNICODE_SUPPORT
  76 # define BB_NUL ((wchar_t)0)
  77 # define CHAR_T wchar_t
  78 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  79 # if ENABLE_FEATURE_EDITING_VI
  80 static bool BB_isalnum_or_underscore(CHAR_T c) {
  81         return ((unsigned)c < 256 && isalnum(c)) || c == '_';
  82 }
  83 # endif
  84 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  85 # undef isspace
  86 # undef isalnum
  87 # undef ispunct
  88 # undef isprint
  89 # define isspace isspace_must_not_be_used
  90 # define isalnum isalnum_must_not_be_used
  91 # define ispunct ispunct_must_not_be_used
  92 # define isprint isprint_must_not_be_used
  93 #else
  94 # define BB_NUL '\0'
  95 # define CHAR_T char
  96 # define BB_isspace(c) isspace(c)
  97 # if ENABLE_FEATURE_EDITING_VI
  98 static bool BB_isalnum_or_underscore(CHAR_T c) {
  99         return ((unsigned)c < 256 && isalnum(c)) || c == '_';
 100 }
 101 # endif
 102 # define BB_ispunct(c) ispunct(c)
 103 #endif
 104 #if ENABLE_UNICODE_PRESERVE_BROKEN
 105 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
 106 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
 107 #else
 108 # define unicode_is_raw_byte(wc)     0
 109 #endif
 110
 111
 112 #define ESC "\033"
 113
 114 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 115 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 116
 117
 118 enum {
 119         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 120                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 121                       : 0x7ff0
 122 };
 123
 124 #if ENABLE_USERNAME_OR_HOMEDIR
 125 static const char null_str[] ALIGN1 = "";
 126 #endif
 127
 128 /* We try to minimize both static and stack usage. */
 129 struct lineedit_statics {
 130         line_input_t *state;
 131
 132         unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 133
 134         unsigned cmdedit_x;        /* real x (col) terminal position */
 135         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 136         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 137
 138         unsigned cursor;
 139         int command_len; /* must be signed */
 140         /* signed maxsize: we want x in "if (x > S.maxsize)"
 141          * to _not_ be promoted to unsigned */
 142         int maxsize;
 143         CHAR_T *command_ps;
 144
 145         const char *cmdedit_prompt;
 146
 147 #if ENABLE_USERNAME_OR_HOMEDIR
 148         char *user_buf;
 149         char *home_pwd_buf; /* = (char*)null_str; */
 150 #endif
 151
 152 #if ENABLE_FEATURE_TAB_COMPLETION
 153         char **matches;
 154         unsigned num_matches;
 155 #endif
 156
 157         unsigned SIGWINCH_saved;
 158         volatile unsigned SIGWINCH_count;
 159         volatile smallint ok_to_redraw;
 160
 161 #if ENABLE_FEATURE_EDITING_VI
 162 # define DELBUFSIZ 128
 163         smallint newdelflag;     /* whether delbuf should be reused yet */
 164         CHAR_T *delptr;
 165         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 166 #endif
 167 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 168         smallint sent_ESC_br6n;
 169 #endif
 170
 171         /* Largish struct, keeping it last results in smaller code */
 172         struct sigaction SIGWINCH_handler;
 173 };
 174
 175 /* See lineedit_ptr_hack.c */
 176 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 177
 178 #define S (*lineedit_ptr_to_statics)
 179 #define state            (S.state           )
 180 #define cmdedit_termw    (S.cmdedit_termw   )
 181 #define cmdedit_x        (S.cmdedit_x       )
 182 #define cmdedit_y        (S.cmdedit_y       )
 183 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 184 #define cursor           (S.cursor          )
 185 #define command_len      (S.command_len     )
 186 #define command_ps       (S.command_ps      )
 187 #define cmdedit_prompt   (S.cmdedit_prompt  )
 188 #define user_buf         (S.user_buf        )
 189 #define home_pwd_buf     (S.home_pwd_buf    )
 190 #define matches          (S.matches         )
 191 #define num_matches      (S.num_matches     )
 192 #define delptr           (S.delptr          )
 193 #define newdelflag       (S.newdelflag      )
 194 #define delbuf           (S.delbuf          )
 195
 196 #define INIT_S() do { \
 197         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 198         barrier(); \
 199         cmdedit_termw = 80; \
 200         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 201         IF_FEATURE_EDITING_VI(delptr = delbuf;) \
 202 } while (0)
 203
 204 static void deinit_S(void)
 205 {
 206 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 207         /* This one is allocated only if FANCY_PROMPT is on
 208          * (otherwise it points to verbatim prompt (NOT malloced)) */
 209         free((char*)cmdedit_prompt);
 210 #endif
 211 #if ENABLE_USERNAME_OR_HOMEDIR
 212         free(user_buf);
 213         if (home_pwd_buf != null_str)
 214                 free(home_pwd_buf);
 215 #endif
 216         free(lineedit_ptr_to_statics);
 217 }
 218 #define DEINIT_S() deinit_S()
 219
 220
 221 #if ENABLE_UNICODE_SUPPORT
 222 static size_t load_string(const char *src)
 223 {
 224         if (unicode_status == UNICODE_ON) {
 225                 ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
 226                 if (len < 0)
 227                         len = 0;
 228                 command_ps[len] = BB_NUL;
 229                 return len;
 230         } else {
 231                 unsigned i = 0;
 232                 while (src[i] && i < S.maxsize - 1) {
 233                         command_ps[i] = src[i];
 234                         i++;
 235                 }
 236                 command_ps[i] = BB_NUL;
 237                 return i;
 238         }
 239 }
 240 static unsigned save_string(char *dst, unsigned maxsize)
 241 {
 242         if (unicode_status == UNICODE_ON) {
 243 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 244                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 245                 if (len < 0)
 246                         len = 0;
 247                 dst[len] = '\0';
 248                 return len;
 249 # else
 250                 unsigned dstpos = 0;
 251                 unsigned srcpos = 0;
 252
 253                 maxsize--;
 254                 while (dstpos < maxsize) {
 255                         wchar_t wc;
 256                         int n = srcpos;
 257
 258                         /* Convert up to 1st invalid byte (or up to end) */
 259                         while ((wc = command_ps[srcpos]) != BB_NUL
 260                             && !unicode_is_raw_byte(wc)
 261                         ) {
 262                                 srcpos++;
 263                         }
 264                         command_ps[srcpos] = BB_NUL;
 265                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 266                         if (n < 0) /* should not happen */
 267                                 break;
 268                         dstpos += n;
 269                         if (wc == BB_NUL) /* usually is */
 270                                 break;
 271
 272                         /* We do have invalid byte here! */
 273                         command_ps[srcpos] = wc; /* restore it */
 274                         srcpos++;
 275                         if (dstpos == maxsize)
 276                                 break;
 277                         dst[dstpos++] = (char) wc;
 278                 }
 279                 dst[dstpos] = '\0';
 280                 return dstpos;
 281 # endif
 282         } else {
 283                 unsigned i = 0;
 284                 while ((dst[i] = command_ps[i]) != 0)
 285                         i++;
 286                 return i;
 287         }
 288 }
 289 /* I thought just fputwc(c, stdout) would work. But no... */
 290 static void BB_PUTCHAR(wchar_t c)
 291 {
 292         if (unicode_status == UNICODE_ON) {
 293                 char buf[MB_CUR_MAX + 1];
 294                 mbstate_t mbst = { 0 };
 295                 ssize_t len = wcrtomb(buf, c, &mbst);
 296                 if (len > 0) {
 297                         buf[len] = '\0';
 298                         fputs(buf, stdout);
 299                 }
 300         } else {
 301                 /* In this case, c is always one byte */
 302                 putchar(c);
 303         }
 304 }
 305 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 306 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 307 # else
 308 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 309 #  define adjust_width_and_validate_wc(width_adj, wc) \
 310         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 311 # endif
 312 {
 313         int w = 1;
 314
 315         if (unicode_status == UNICODE_ON) {
 316                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 317                         /* note: also true for unicode_is_raw_byte(wc) */
 318                         goto subst;
 319                 }
 320                 w = wcwidth(wc);
 321                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 322                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 323                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 324                 ) {
 325  subst:
 326                         w = 1;
 327                         wc = CONFIG_SUBST_WCHAR;
 328                 }
 329         }
 330
 331 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 332         *width_adj += w;
 333 #endif
 334         return wc;
 335 }
 336 #else /* !UNICODE */
 337 static size_t load_string(const char *src)
 338 {
 339         safe_strncpy(command_ps, src, S.maxsize);
 340         return strlen(command_ps);
 341 }
 342 # if ENABLE_FEATURE_TAB_COMPLETION
 343 static void save_string(char *dst, unsigned maxsize)
 344 {
 345         safe_strncpy(dst, command_ps, maxsize);
 346 }
 347 # endif
 348 # define BB_PUTCHAR(c) bb_putchar(c)
 349 /* Should never be called: */
 350 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 351 #endif
 352
 353
 354 /* Put 'command_ps[cursor]', cursor++.
 355  * Advance cursor on screen. If we reached right margin, scroll text up
 356  * and remove terminal margin effect by printing 'next_char' */
 357 #define HACK_FOR_WRONG_WIDTH 1
 358 static void put_cur_glyph_and_inc_cursor(void)
 359 {
 360         CHAR_T c = command_ps[cursor];
 361         unsigned width = 0;
 362         int ofs_to_right;
 363
 364         if (c == BB_NUL) {
 365                 /* erase character after end of input string */
 366                 c = ' ';
 367         } else {
 368                 /* advance cursor only if we aren't at the end yet */
 369                 cursor++;
 370                 if (unicode_status == UNICODE_ON) {
 371                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 372                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 373                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 374                 } else {
 375                         cmdedit_x++;
 376                 }
 377         }
 378
 379         ofs_to_right = cmdedit_x - cmdedit_termw;
 380         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 381                 /* c fits on this line */
 382                 BB_PUTCHAR(c);
 383         }
 384
 385         if (ofs_to_right >= 0) {
 386                 /* we go to the next line */
 387 #if HACK_FOR_WRONG_WIDTH
 388                 /* This works better if our idea of term width is wrong
 389                  * and it is actually wider (often happens on serial lines).
 390                  * Printing CR,LF *forces* cursor to next line.
 391                  * OTOH if terminal width is correct AND terminal does NOT
 392                  * have automargin (IOW: it is moving cursor to next line
 393                  * by itself (which is wrong for VT-10x terminals)),
 394                  * this will break things: there will be one extra empty line */
 395                 puts("\r"); /* + implicit '\n' */
 396 #else
 397                 /* VT-10x terminals don't wrap cursor to next line when last char
 398                  * on the line is printed - cursor stays "over" this char.
 399                  * Need to print _next_ char too (first one to appear on next line)
 400                  * to make cursor move down to next line.
 401                  */
 402                 /* Works ok only if cmdedit_termw is correct. */
 403                 c = command_ps[cursor];
 404                 if (c == BB_NUL)
 405                         c = ' ';
 406                 BB_PUTCHAR(c);
 407                 bb_putchar('\b');
 408 #endif
 409                 cmdedit_y++;
 410                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 411                         width = 0;
 412                 } else { /* ofs_to_right > 0 */
 413                         /* wide char c didn't fit on prev line */
 414                         BB_PUTCHAR(c);
 415                 }
 416                 cmdedit_x = width;
 417         }
 418 }
 419
 420 /* Move to end of line (by printing all chars till the end) */
 421 static void put_till_end_and_adv_cursor(void)
 422 {
 423         while (cursor < command_len)
 424                 put_cur_glyph_and_inc_cursor();
 425 }
 426
 427 /* Go to the next line */
 428 static void goto_new_line(void)
 429 {
 430         put_till_end_and_adv_cursor();
 431         if (cmdedit_x != 0)
 432                 bb_putchar('\n');
 433 }
 434
 435 static void beep(void)
 436 {
 437         bb_putchar('\007');
 438 }
 439
 440 static void put_prompt(void)
 441 {
 442         fputs(cmdedit_prompt, stdout);
 443         cursor = 0;
 444         cmdedit_y = cmdedit_prmt_len / cmdedit_termw; /* new quasireal y */
 445         cmdedit_x = cmdedit_prmt_len % cmdedit_termw;
 446 }
 447
 448 /* Move back one character */
 449 /* (optimized for slow terminals) */
 450 static void input_backward(unsigned num)
 451 {
 452         if (num > cursor)
 453                 num = cursor;
 454         if (num == 0)
 455                 return;
 456         cursor -= num;
 457
 458         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 459          && unicode_status == UNICODE_ON
 460         ) {
 461                 /* correct NUM to be equal to _screen_ width */
 462                 int n = num;
 463                 num = 0;
 464                 while (--n >= 0)
 465                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 466                 if (num == 0)
 467                         return;
 468         }
 469
 470         if (cmdedit_x >= num) {
 471                 cmdedit_x -= num;
 472                 if (num <= 4) {
 473                         /* This is longer by 5 bytes on x86.
 474                          * Also gets miscompiled for ARM users
 475                          * (busybox.net/bugs/view.php?id=2274).
 476                          * printf(("\b\b\b\b" + 4) - num);
 477                          * return;
 478                          */
 479                         do {
 480                                 bb_putchar('\b');
 481                         } while (--num);
 482                         return;
 483                 }
 484                 printf(ESC"[%uD", num);
 485                 return;
 486         }
 487
 488         /* Need to go one or more lines up */
 489         if (ENABLE_UNICODE_WIDE_WCHARS) {
 490                 /* With wide chars, it is hard to "backtrack"
 491                  * and reliably figure out where to put cursor.
 492                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 493                  * |prompt: <><> |
 494                  * |<><><><><><> |
 495                  * |_            |
 496                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 497                  * We need to go up one line, and then - how do we know that
 498                  * we need to go *10* positions to the right? Because
 499                  * |prompt: <>#<>|
 500                  * |<><><>#<><><>|
 501                  * |_            |
 502                  * in this situation we need to go *11* positions to the right.
 503                  *
 504                  * A simpler thing to do is to redraw everything from the start
 505                  * up to new cursor position (which is already known):
 506                  */
 507                 unsigned sv_cursor;
 508                 /* go to 1st column; go up to first line */
 509                 printf("\r" ESC"[%uA", cmdedit_y);
 510                 cmdedit_y = 0;
 511                 sv_cursor = cursor;
 512                 put_prompt(); /* sets cursor to 0 */
 513                 while (cursor < sv_cursor)
 514                         put_cur_glyph_and_inc_cursor();
 515         } else {
 516                 int lines_up;
 517                 /* num = chars to go back from the beginning of current line: */
 518                 num -= cmdedit_x;
 519                 /* num=1...w: one line up, w+1...2w: two, etc: */
 520                 lines_up = 1 + (num - 1) / cmdedit_termw;
 521                 cmdedit_x = (cmdedit_termw * cmdedit_y - num) % cmdedit_termw;
 522                 cmdedit_y -= lines_up;
 523                 /* go to 1st column; go up */
 524                 printf("\r" ESC"[%uA", lines_up);
 525                 /* go to correct column.
 526                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 527                  * need to *make sure* we skip it if cmdedit_x == 0 */
 528                 if (cmdedit_x)
 529                         printf(ESC"[%uC", cmdedit_x);
 530         }
 531 }
 532
 533 /* draw prompt, editor line, and clear tail */
 534 static void redraw(int y, int back_cursor)
 535 {
 536         if (y > 0) /* up y lines */
 537                 printf(ESC"[%uA", y);
 538         bb_putchar('\r');
 539         put_prompt();
 540         put_till_end_and_adv_cursor();
 541         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 542         input_backward(back_cursor);
 543 }
 544
 545 /* Delete the char in front of the cursor, optionally saving it
 546  * for later putback */
 547 #if !ENABLE_FEATURE_EDITING_VI
 548 static void input_delete(void)
 549 #define input_delete(save) input_delete()
 550 #else
 551 static void input_delete(int save)
 552 #endif
 553 {
 554         int j = cursor;
 555
 556         if (j == (int)command_len)
 557                 return;
 558
 559 #if ENABLE_FEATURE_EDITING_VI
 560         if (save) {
 561                 if (newdelflag) {
 562                         delptr = delbuf;
 563                         newdelflag = 0;
 564                 }
 565                 if ((delptr - delbuf) < DELBUFSIZ)
 566                         *delptr++ = command_ps[j];
 567         }
 568 #endif
 569
 570         memmove(command_ps + j, command_ps + j + 1,
 571                         /* (command_len + 1 [because of NUL]) - (j + 1)
 572                          * simplified into (command_len - j) */
 573                         (command_len - j) * sizeof(command_ps[0]));
 574         command_len--;
 575         put_till_end_and_adv_cursor();
 576         /* Last char is still visible, erase it (and more) */
 577         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 578         input_backward(cursor - j);     /* back to old pos cursor */
 579 }
 580
 581 #if ENABLE_FEATURE_EDITING_VI
 582 static void put(void)
 583 {
 584         int ocursor;
 585         int j = delptr - delbuf;
 586
 587         if (j == 0)
 588                 return;
 589         ocursor = cursor;
 590         /* open hole and then fill it */
 591         memmove(command_ps + cursor + j, command_ps + cursor,
 592                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 593         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 594         command_len += j;
 595         put_till_end_and_adv_cursor();
 596         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 597 }
 598 #endif
 599
 600 /* Delete the char in back of the cursor */
 601 static void input_backspace(void)
 602 {
 603         if (cursor > 0) {
 604                 input_backward(1);
 605                 input_delete(0);
 606         }
 607 }
 608
 609 /* Move forward one character */
 610 static void input_forward(void)
 611 {
 612         if (cursor < command_len)
 613                 put_cur_glyph_and_inc_cursor();
 614 }
 615
 616 #if ENABLE_FEATURE_TAB_COMPLETION
 617
 618 //FIXME:
 619 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 620 //matches the file named "foo bar", which is untrue.
 621 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 622 //not "foo bar <cursor>...
 623
 624 static void free_tab_completion_data(void)
 625 {
 626         if (matches) {
 627                 while (num_matches)
 628                         free(matches[--num_matches]);
 629                 free(matches);
 630                 matches = NULL;
 631         }
 632 }
 633
 634 static void add_match(char *matched)
 635 {
 636         matches = xrealloc_vector(matches, 4, num_matches);
 637         matches[num_matches] = matched;
 638         num_matches++;
 639 }
 640
 641 # if ENABLE_FEATURE_USERNAME_COMPLETION
 642 /* Replace "~user/..." with "/homedir/...".
 643  * The parameter is malloced, free it or return it
 644  * unchanged if no user is matched.
 645  */
 646 static char *username_path_completion(char *ud)
 647 {
 648         struct passwd *entry;
 649         char *tilde_name = ud;
 650         char *home = NULL;
 651
 652         ud++; /* skip ~ */
 653         if (*ud == '/') {       /* "~/..." */
 654                 home = home_pwd_buf;
 655         } else {
 656                 /* "~user/..." */
 657                 ud = strchr(ud, '/');
 658                 *ud = '\0';           /* "~user" */
 659                 entry = getpwnam(tilde_name + 1);
 660                 *ud = '/';            /* restore "~user/..." */
 661                 if (entry)
 662                         home = entry->pw_dir;
 663         }
 664         if (home) {
 665                 ud = concat_path_file(home, ud);
 666                 free(tilde_name);
 667                 tilde_name = ud;
 668         }
 669         return tilde_name;
 670 }
 671
 672 /* ~use<tab> - find all users with this prefix.
 673  * Return the length of the prefix used for matching.
 674  */
 675 static NOINLINE unsigned complete_username(const char *ud)
 676 {
 677         struct passwd *pw;
 678         unsigned userlen;
 679
 680         ud++; /* skip ~ */
 681         userlen = strlen(ud);
 682
 683         setpwent();
 684         while ((pw = getpwent()) != NULL) {
 685                 /* Null usernames should result in all users as possible completions. */
 686                 if (/* !ud[0] || */ is_prefixed_with(pw->pw_name, ud)) {
 687                         add_match(xasprintf("~%s/", pw->pw_name));
 688                 }
 689         }
 690         endpwent(); /* don't keep password file open */
 691
 692         return 1 + userlen;
 693 }
 694 # endif  /* FEATURE_USERNAME_COMPLETION */
 695
 696 enum {
 697         FIND_EXE_ONLY = 0,
 698         FIND_DIR_ONLY = 1,
 699         FIND_FILE_ONLY = 2,
 700 };
 701
 702 static int path_parse(char ***p)
 703 {
 704         int npth;
 705         const char *pth;
 706         char *tmp;
 707         char **res;
 708
 709         if (state->flags & WITH_PATH_LOOKUP)
 710                 pth = state->path_lookup;
 711         else
 712                 pth = getenv("PATH");
 713
 714         /* PATH="" or PATH=":"? */
 715         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 716                 return 1;
 717
 718         tmp = (char*)pth;
 719         npth = 1; /* path component count */
 720         while (1) {
 721                 tmp = strchr(tmp, ':');
 722                 if (!tmp)
 723                         break;
 724                 tmp++;
 725                 if (*tmp == '\0')
 726                         break;  /* :<empty> */
 727                 npth++;
 728         }
 729
 730         *p = res = xmalloc(npth * sizeof(res[0]));
 731         res[0] = tmp = xstrdup(pth);
 732         npth = 1;
 733         while (1) {
 734                 tmp = strchr(tmp, ':');
 735                 if (!tmp)
 736                         break;
 737                 *tmp++ = '\0'; /* ':' -> '\0' */
 738                 if (*tmp == '\0')
 739                         break; /* :<empty> */
 740                 res[npth++] = tmp;
 741         }
 742         return npth;
 743 }
 744
 745 /* Complete command, directory or file name.
 746  * Return the length of the prefix used for matching.
 747  */
 748 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 749 {
 750         char *path1[1];
 751         char **paths = path1;
 752         int npaths;
 753         int i;
 754         unsigned pf_len;
 755         const char *pfind;
 756         char *dirbuf = NULL;
 757
 758         npaths = 1;
 759         path1[0] = (char*)".";
 760
 761         pfind = strrchr(command, '/');
 762         if (!pfind) {
 763                 if (type == FIND_EXE_ONLY)
 764                         npaths = path_parse(&paths);
 765                 pfind = command;
 766         } else {
 767                 /* point to 'l' in "..../last_component" */
 768                 pfind++;
 769                 /* dirbuf = ".../.../.../" */
 770                 dirbuf = xstrndup(command, pfind - command);
 771 # if ENABLE_FEATURE_USERNAME_COMPLETION
 772                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 773                         dirbuf = username_path_completion(dirbuf);
 774 # endif
 775                 path1[0] = dirbuf;
 776         }
 777         pf_len = strlen(pfind);
 778
 779 #if ENABLE_FEATURE_SH_STANDALONE && NUM_APPLETS != 1
 780         if (type == FIND_EXE_ONLY && !dirbuf) {
 781                 const char *p = applet_names;
 782
 783                 while (*p) {
 784                         if (strncmp(pfind, p, pf_len) == 0)
 785                                 add_match(xstrdup(p));
 786                         while (*p++ != '\0')
 787                                 continue;
 788                 }
 789         }
 790 #endif
 791
 792         for (i = 0; i < npaths; i++) {
 793                 DIR *dir;
 794                 struct dirent *next;
 795                 struct stat st;
 796                 char *found;
 797
 798                 dir = opendir(paths[i]);
 799                 if (!dir)
 800                         continue; /* don't print an error */
 801
 802                 while ((next = readdir(dir)) != NULL) {
 803                         unsigned len;
 804                         const char *name_found = next->d_name;
 805
 806                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 807                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 808                                 continue;
 809                         /* match? */
 810                         if (!is_prefixed_with(name_found, pfind))
 811                                 continue; /* no */
 812
 813                         found = concat_path_file(paths[i], name_found);
 814                         /* NB: stat() first so that we see is it a directory;
 815                          * but if that fails, use lstat() so that
 816                          * we still match dangling links */
 817                         if (stat(found, &st) && lstat(found, &st))
 818                                 goto cont; /* hmm, remove in progress? */
 819
 820                         /* Save only name */
 821                         len = strlen(name_found);
 822                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 823                         strcpy(found, name_found);
 824
 825                         if (S_ISDIR(st.st_mode)) {
 826                                 /* name is a directory, add slash */
 827                                 found[len] = '/';
 828                                 found[len + 1] = '\0';
 829                         } else {
 830                                 /* skip files if looking for dirs only (example: cd) */
 831                                 if (type == FIND_DIR_ONLY)
 832                                         goto cont;
 833                         }
 834                         /* add it to the list */
 835                         add_match(found);
 836                         continue;
 837  cont:
 838                         free(found);
 839                 }
 840                 closedir(dir);
 841         } /* for every path */
 842
 843         if (paths != path1) {
 844                 free(paths[0]); /* allocated memory is only in first member */
 845                 free(paths);
 846         }
 847         free(dirbuf);
 848
 849         return pf_len;
 850 }
 851
 852 /* build_match_prefix:
 853  * On entry, match_buf contains everything up to cursor at the moment <tab>
 854  * was pressed. This function looks at it, figures out what part of it
 855  * constitutes the command/file/directory prefix to use for completion,
 856  * and rewrites match_buf to contain only that part.
 857  */
 858 #define dbg_bmp 0
 859 /* Helpers: */
 860 /* QUOT is used on elements of int_buf[], which are bytes,
 861  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 862  */
 863 #define QUOT (UCHAR_MAX+1)
 864 static void remove_chunk(int16_t *int_buf, int beg, int end)
 865 {
 866         /* beg must be <= end */
 867         if (beg == end)
 868                 return;
 869
 870         while ((int_buf[beg] = int_buf[end]) != 0)
 871                 beg++, end++;
 872
 873         if (dbg_bmp) {
 874                 int i;
 875                 for (i = 0; int_buf[i]; i++)
 876                         bb_putchar((unsigned char)int_buf[i]);
 877                 bb_putchar('\n');
 878         }
 879 }
 880 /* Caller ensures that match_buf points to a malloced buffer
 881  * big enough to hold strlen(match_buf)*2 + 2
 882  */
 883 static NOINLINE int build_match_prefix(char *match_buf)
 884 {
 885         int i, j;
 886         int command_mode;
 887         int16_t *int_buf = (int16_t*)match_buf;
 888
 889         if (dbg_bmp) printf("\n%s\n", match_buf);
 890
 891         /* Copy in reverse order, since they overlap */
 892         i = strlen(match_buf);
 893         do {
 894                 int_buf[i] = (unsigned char)match_buf[i];
 895                 i--;
 896         } while (i >= 0);
 897
 898         /* Mark every \c as "quoted c" */
 899         for (i = 0; int_buf[i]; i++) {
 900                 if (int_buf[i] == '\\') {
 901                         remove_chunk(int_buf, i, i + 1);
 902                         int_buf[i] |= QUOT;
 903                 }
 904         }
 905         /* Quote-mark "chars" and 'chars', drop delimiters */
 906         {
 907                 int in_quote = 0;
 908                 i = 0;
 909                 while (int_buf[i]) {
 910                         int cur = int_buf[i];
 911                         if (!cur)
 912                                 break;
 913                         if (cur == '\'' || cur == '"') {
 914                                 if (!in_quote || (cur == in_quote)) {
 915                                         in_quote ^= cur;
 916                                         remove_chunk(int_buf, i, i + 1);
 917                                         continue;
 918                                 }
 919                         }
 920                         if (in_quote)
 921                                 int_buf[i] = cur | QUOT;
 922                         i++;
 923                 }
 924         }
 925
 926         /* Remove everything up to command delimiters:
 927          * ';' ';;' '&' '|' '&&' '||',
 928          * but careful with '>&' '<&' '>|'
 929          */
 930         for (i = 0; int_buf[i]; i++) {
 931                 int cur = int_buf[i];
 932                 if (cur == ';' || cur == '&' || cur == '|') {
 933                         int prev = i ? int_buf[i - 1] : 0;
 934                         if (cur == '&' && (prev == '>' || prev == '<')) {
 935                                 continue;
 936                         } else if (cur == '|' && prev == '>') {
 937                                 continue;
 938                         }
 939                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 940                         i = -1;  /* back to square 1 */
 941                 }
 942         }
 943         /* Remove all `cmd` */
 944         for (i = 0; int_buf[i]; i++) {
 945                 if (int_buf[i] == '`') {
 946                         for (j = i + 1; int_buf[j]; j++) {
 947                                 if (int_buf[j] == '`') {
 948                                         /* `cmd` should count as a word:
 949                                          * `cmd` c<tab> should search for files c*,
 950                                          * not commands c*. Therefore we don't drop
 951                                          * `cmd` entirely, we replace it with single `.
 952                                          */
 953                                         remove_chunk(int_buf, i, j);
 954                                         goto next;
 955                                 }
 956                         }
 957                         /* No closing ` - command mode, remove all up to ` */
 958                         remove_chunk(int_buf, 0, i + 1);
 959                         break;
 960  next: ;
 961                 }
 962         }
 963
 964         /* Remove "cmd (" and "cmd {"
 965          * Example: "if { c<tab>"
 966          * In this example, c should be matched as command pfx.
 967          */
 968         for (i = 0; int_buf[i]; i++) {
 969                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 970                         remove_chunk(int_buf, 0, i + 1);
 971                         i = -1;  /* back to square 1 */
 972                 }
 973         }
 974
 975         /* Remove leading unquoted spaces */
 976         for (i = 0; int_buf[i]; i++)
 977                 if (int_buf[i] != ' ')
 978                         break;
 979         remove_chunk(int_buf, 0, i);
 980
 981         /* Determine completion mode */
 982         command_mode = FIND_EXE_ONLY;
 983         for (i = 0; int_buf[i]; i++) {
 984                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 985                         if (int_buf[i] == ' '
 986                          && command_mode == FIND_EXE_ONLY
 987                          && (char)int_buf[0] == 'c'
 988                          && (char)int_buf[1] == 'd'
 989                          && i == 2 /* -> int_buf[2] == ' ' */
 990                         ) {
 991                                 command_mode = FIND_DIR_ONLY;
 992                         } else {
 993                                 command_mode = FIND_FILE_ONLY;
 994                                 break;
 995                         }
 996                 }
 997         }
 998         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 999
1000         /* Remove everything except last word */
1001         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
1002                 continue;
1003         for (--i; i >= 0; i--) {
1004                 int cur = int_buf[i];
1005                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
1006                         remove_chunk(int_buf, 0, i + 1);
1007                         break;
1008                 }
1009         }
1010
1011         /* Convert back to string of _chars_ */
1012         i = 0;
1013         while ((match_buf[i] = int_buf[i]) != '\0')
1014                 i++;
1015
1016         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
1017
1018         return command_mode;
1019 }
1020
1021 /*
1022  * Display by column (original idea from ls applet,
1023  * very optimized by me [Vladimir] :)
1024  */
1025 static void showfiles(void)
1026 {
1027         int ncols, row;
1028         int column_width = 0;
1029         int nfiles = num_matches;
1030         int nrows = nfiles;
1031         int l;
1032
1033         /* find the longest file name - use that as the column width */
1034         for (row = 0; row < nrows; row++) {
1035                 l = unicode_strwidth(matches[row]);
1036                 if (column_width < l)
1037                         column_width = l;
1038         }
1039         column_width += 2;              /* min space for columns */
1040         ncols = cmdedit_termw / column_width;
1041
1042         if (ncols > 1) {
1043                 nrows /= ncols;
1044                 if (nfiles % ncols)
1045                         nrows++;        /* round up fractionals */
1046         } else {
1047                 ncols = 1;
1048         }
1049         for (row = 0; row < nrows; row++) {
1050                 int n = row;
1051                 int nc;
1052
1053                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1054                         printf("%s%-*s", matches[n],
1055                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1056                         );
1057                 }
1058                 if (ENABLE_UNICODE_SUPPORT)
1059                         puts(printable_string(NULL, matches[n]));
1060                 else
1061                         puts(matches[n]);
1062         }
1063 }
1064
1065 static const char *is_special_char(char c)
1066 {
1067         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1068 }
1069
1070 static char *quote_special_chars(char *found)
1071 {
1072         int l = 0;
1073         char *s = xzalloc((strlen(found) + 1) * 2);
1074
1075         while (*found) {
1076                 if (is_special_char(*found))
1077                         s[l++] = '\\';
1078                 s[l++] = *found++;
1079         }
1080         /* s[l] = '\0'; - already is */
1081         return s;
1082 }
1083
1084 /* Do TAB completion */
1085 static NOINLINE void input_tab(smallint *lastWasTab)
1086 {
1087         char *chosen_match;
1088         char *match_buf;
1089         size_t len_found;
1090         /* Length of string used for matching */
1091         unsigned match_pfx_len = match_pfx_len;
1092         int find_type;
1093 # if ENABLE_UNICODE_SUPPORT
1094         /* cursor pos in command converted to multibyte form */
1095         int cursor_mb;
1096 # endif
1097         if (!(state->flags & TAB_COMPLETION))
1098                 return;
1099
1100         if (*lastWasTab) {
1101                 /* The last char was a TAB too.
1102                  * Print a list of all the available choices.
1103                  */
1104                 if (num_matches > 0) {
1105                         /* cursor will be changed by goto_new_line() */
1106                         int sav_cursor = cursor;
1107                         goto_new_line();
1108                         showfiles();
1109                         redraw(0, command_len - sav_cursor);
1110                 }
1111                 return;
1112         }
1113
1114         *lastWasTab = 1;
1115         chosen_match = NULL;
1116
1117         /* Make a local copy of the string up to the position of the cursor.
1118          * build_match_prefix will expand it into int16_t's, need to allocate
1119          * twice as much as the string_len+1.
1120          * (we then also (ab)use this extra space later - see (**))
1121          */
1122         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1123 # if !ENABLE_UNICODE_SUPPORT
1124         save_string(match_buf, cursor + 1); /* +1 for NUL */
1125 # else
1126         {
1127                 CHAR_T wc = command_ps[cursor];
1128                 command_ps[cursor] = BB_NUL;
1129                 save_string(match_buf, MAX_LINELEN);
1130                 command_ps[cursor] = wc;
1131                 cursor_mb = strlen(match_buf);
1132         }
1133 # endif
1134         find_type = build_match_prefix(match_buf);
1135
1136         /* Free up any memory already allocated */
1137         free_tab_completion_data();
1138
1139 # if ENABLE_FEATURE_USERNAME_COMPLETION
1140         /* If the word starts with ~ and there is no slash in the word,
1141          * then try completing this word as a username. */
1142         if (state->flags & USERNAME_COMPLETION)
1143                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1144                         match_pfx_len = complete_username(match_buf);
1145 # endif
1146         /* If complete_username() did not match,
1147          * try to match a command in $PATH, or a directory, or a file */
1148         if (!matches)
1149                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1150
1151         /* Account for backslashes which will be inserted
1152          * by quote_special_chars() later */
1153         {
1154                 const char *e = match_buf + strlen(match_buf);
1155                 const char *s = e - match_pfx_len;
1156                 while (s < e)
1157                         if (is_special_char(*s++))
1158                                 match_pfx_len++;
1159         }
1160
1161         /* Remove duplicates */
1162         if (matches) {
1163                 unsigned i, n = 0;
1164                 qsort_string_vector(matches, num_matches);
1165                 for (i = 0; i < num_matches - 1; ++i) {
1166                         //if (matches[i] && matches[i+1]) { /* paranoia */
1167                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1168                                         free(matches[i]);
1169                                         //matches[i] = NULL; /* paranoia */
1170                                 } else {
1171                                         matches[n++] = matches[i];
1172                                 }
1173                         //}
1174                 }
1175                 matches[n++] = matches[i];
1176                 num_matches = n;
1177         }
1178
1179         /* Did we find exactly one match? */
1180         if (num_matches != 1) { /* no */
1181                 char *cp;
1182                 beep();
1183                 if (!matches)
1184                         goto ret; /* no matches at all */
1185                 /* Find common prefix */
1186                 chosen_match = xstrdup(matches[0]);
1187                 for (cp = chosen_match; *cp; cp++) {
1188                         unsigned n;
1189                         for (n = 1; n < num_matches; n++) {
1190                                 if (matches[n][cp - chosen_match] != *cp) {
1191                                         goto stop;
1192                                 }
1193                         }
1194                 }
1195  stop:
1196                 if (cp == chosen_match) { /* have unique prefix? */
1197                         goto ret; /* no */
1198                 }
1199                 *cp = '\0';
1200                 cp = quote_special_chars(chosen_match);
1201                 free(chosen_match);
1202                 chosen_match = cp;
1203                 len_found = strlen(chosen_match);
1204         } else {                        /* exactly one match */
1205                 /* Next <tab> is not a double-tab */
1206                 *lastWasTab = 0;
1207
1208                 chosen_match = quote_special_chars(matches[0]);
1209                 len_found = strlen(chosen_match);
1210                 if (chosen_match[len_found-1] != '/') {
1211                         chosen_match[len_found] = ' ';
1212                         chosen_match[++len_found] = '\0';
1213                 }
1214         }
1215
1216 # if !ENABLE_UNICODE_SUPPORT
1217         /* Have space to place the match? */
1218         /* The result consists of three parts with these lengths: */
1219         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1220         /* it simplifies into: */
1221         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1222                 int pos;
1223                 /* save tail */
1224                 strcpy(match_buf, &command_ps[cursor]);
1225                 /* add match and tail */
1226                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1227                 command_len = strlen(command_ps);
1228                 /* new pos */
1229                 pos = cursor + len_found - match_pfx_len;
1230                 /* write out the matched command */
1231                 redraw(cmdedit_y, command_len - pos);
1232         }
1233 # else
1234         {
1235                 /* Use 2nd half of match_buf as scratch space - see (**) */
1236                 char *command = match_buf + MAX_LINELEN;
1237                 int len = save_string(command, MAX_LINELEN);
1238                 /* Have space to place the match? */
1239                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1240                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1241                         int pos;
1242                         /* save tail */
1243                         strcpy(match_buf, &command[cursor_mb]);
1244                         /* where do we want to have cursor after all? */
1245                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1246                         len = load_string(command);
1247                         /* add match and tail */
1248                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1249                         command_len = load_string(command);
1250                         /* write out the matched command */
1251                         /* paranoia: load_string can return 0 on conv error,
1252                          * prevent passing pos = (0 - 12) to redraw */
1253                         pos = command_len - len;
1254                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1255                 }
1256         }
1257 # endif
1258  ret:
1259         free(chosen_match);
1260         free(match_buf);
1261 }
1262
1263 #endif  /* FEATURE_TAB_COMPLETION */
1264
1265
1266 line_input_t* FAST_FUNC new_line_input_t(int flags)
1267 {
1268         line_input_t *n = xzalloc(sizeof(*n));
1269         n->flags = flags;
1270 #if MAX_HISTORY > 0
1271         n->max_history = MAX_HISTORY;
1272 #endif
1273         return n;
1274 }
1275
1276
1277 #if MAX_HISTORY > 0
1278
1279 unsigned FAST_FUNC size_from_HISTFILESIZE(const char *hp)
1280 {
1281         int size = MAX_HISTORY;
1282         if (hp) {
1283                 size = atoi(hp);
1284                 if (size <= 0)
1285                         return 1;
1286                 if (size > MAX_HISTORY)
1287                         return MAX_HISTORY;
1288         }
1289         return size;
1290 }
1291
1292 static void save_command_ps_at_cur_history(void)
1293 {
1294         if (command_ps[0] != BB_NUL) {
1295                 int cur = state->cur_history;
1296                 free(state->history[cur]);
1297
1298 # if ENABLE_UNICODE_SUPPORT
1299                 {
1300                         char tbuf[MAX_LINELEN];
1301                         save_string(tbuf, sizeof(tbuf));
1302                         state->history[cur] = xstrdup(tbuf);
1303                 }
1304 # else
1305                 state->history[cur] = xstrdup(command_ps);
1306 # endif
1307         }
1308 }
1309
1310 /* state->flags is already checked to be nonzero */
1311 static int get_previous_history(void)
1312 {
1313         if ((state->flags & DO_HISTORY) && state->cur_history) {
1314                 save_command_ps_at_cur_history();
1315                 state->cur_history--;
1316                 return 1;
1317         }
1318         beep();
1319         return 0;
1320 }
1321
1322 static int get_next_history(void)
1323 {
1324         if (state->flags & DO_HISTORY) {
1325                 if (state->cur_history < state->cnt_history) {
1326                         save_command_ps_at_cur_history(); /* save the current history line */
1327                         return ++state->cur_history;
1328                 }
1329         }
1330         beep();
1331         return 0;
1332 }
1333
1334 /* Lists command history. Used by shell 'history' builtins */
1335 void FAST_FUNC show_history(const line_input_t *st)
1336 {
1337         int i;
1338
1339         if (!st)
1340                 return;
1341         for (i = 0; i < st->cnt_history; i++)
1342                 printf("%4d %s\n", i, st->history[i]);
1343 }
1344
1345 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1346 /* We try to ensure that concurrent additions to the history
1347  * do not overwrite each other.
1348  * Otherwise shell users get unhappy.
1349  *
1350  * History file is trimmed lazily, when it grows several times longer
1351  * than configured MAX_HISTORY lines.
1352  */
1353
1354 static void free_line_input_t(line_input_t *n)
1355 {
1356         int i = n->cnt_history;
1357         while (i > 0)
1358                 free(n->history[--i]);
1359         free(n);
1360 }
1361
1362 /* state->flags is already checked to be nonzero */
1363 static void load_history(line_input_t *st_parm)
1364 {
1365         char *temp_h[MAX_HISTORY];
1366         char *line;
1367         FILE *fp;
1368         unsigned idx, i, line_len;
1369
1370         /* NB: do not trash old history if file can't be opened */
1371
1372         fp = fopen_for_read(st_parm->hist_file);
1373         if (fp) {
1374                 /* clean up old history */
1375                 for (idx = st_parm->cnt_history; idx > 0;) {
1376                         idx--;
1377                         free(st_parm->history[idx]);
1378                         st_parm->history[idx] = NULL;
1379                 }
1380
1381                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1382                 memset(temp_h, 0, sizeof(temp_h));
1383                 idx = 0;
1384                 st_parm->cnt_history_in_file = 0;
1385                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1386                         if (line[0] == '\0') {
1387                                 free(line);
1388                                 continue;
1389                         }
1390                         free(temp_h[idx]);
1391                         temp_h[idx] = line;
1392                         st_parm->cnt_history_in_file++;
1393                         idx++;
1394                         if (idx == st_parm->max_history)
1395                                 idx = 0;
1396                 }
1397                 fclose(fp);
1398
1399                 /* find first non-NULL temp_h[], if any */
1400                 if (st_parm->cnt_history_in_file) {
1401                         while (temp_h[idx] == NULL) {
1402                                 idx++;
1403                                 if (idx == st_parm->max_history)
1404                                         idx = 0;
1405                         }
1406                 }
1407
1408                 /* copy temp_h[] to st_parm->history[] */
1409                 for (i = 0; i < st_parm->max_history;) {
1410                         line = temp_h[idx];
1411                         if (!line)
1412                                 break;
1413                         idx++;
1414                         if (idx == st_parm->max_history)
1415                                 idx = 0;
1416                         line_len = strlen(line);
1417                         if (line_len >= MAX_LINELEN)
1418                                 line[MAX_LINELEN-1] = '\0';
1419                         st_parm->history[i++] = line;
1420                 }
1421                 st_parm->cnt_history = i;
1422                 if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
1423                         st_parm->cnt_history_in_file = i;
1424         }
1425 }
1426
1427 #  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1428 void save_history(line_input_t *st)
1429 {
1430         FILE *fp;
1431
1432         if (!st->hist_file)
1433                 return;
1434         if (st->cnt_history <= st->cnt_history_in_file)
1435                 return;
1436
1437         fp = fopen(st->hist_file, "a");
1438         if (fp) {
1439                 int i, fd;
1440                 char *new_name;
1441                 line_input_t *st_temp;
1442
1443                 for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
1444                         fprintf(fp, "%s\n", st->history[i]);
1445                 fclose(fp);
1446
1447                 /* we may have concurrently written entries from others.
1448                  * load them */
1449                 st_temp = new_line_input_t(st->flags);
1450                 st_temp->hist_file = st->hist_file;
1451                 st_temp->max_history = st->max_history;
1452                 load_history(st_temp);
1453
1454                 /* write out temp file and replace hist_file atomically */
1455                 new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
1456                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1457                 if (fd >= 0) {
1458                         fp = xfdopen_for_write(fd);
1459                         for (i = 0; i < st_temp->cnt_history; i++)
1460                                 fprintf(fp, "%s\n", st_temp->history[i]);
1461                         fclose(fp);
1462                         if (rename(new_name, st->hist_file) == 0)
1463                                 st->cnt_history_in_file = st_temp->cnt_history;
1464                 }
1465                 free(new_name);
1466                 free_line_input_t(st_temp);
1467         }
1468 }
1469 #  else
1470 static void save_history(char *str)
1471 {
1472         int fd;
1473         int len, len2;
1474
1475         if (!state->hist_file)
1476                 return;
1477
1478         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1479         if (fd < 0)
1480                 return;
1481         xlseek(fd, 0, SEEK_END); /* paranoia */
1482         len = strlen(str);
1483         str[len] = '\n'; /* we (try to) do atomic write */
1484         len2 = full_write(fd, str, len + 1);
1485         str[len] = '\0';
1486         close(fd);
1487         if (len2 != len + 1)
1488                 return; /* "wtf?" */
1489
1490         /* did we write so much that history file needs trimming? */
1491         state->cnt_history_in_file++;
1492         if (state->cnt_history_in_file > state->max_history * 4) {
1493                 char *new_name;
1494                 line_input_t *st_temp;
1495
1496                 /* we may have concurrently written entries from others.
1497                  * load them */
1498                 st_temp = new_line_input_t(state->flags);
1499                 st_temp->hist_file = state->hist_file;
1500                 st_temp->max_history = state->max_history;
1501                 load_history(st_temp);
1502
1503                 /* write out temp file and replace hist_file atomically */
1504                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1505                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1506                 if (fd >= 0) {
1507                         FILE *fp;
1508                         int i;
1509
1510                         fp = xfdopen_for_write(fd);
1511                         for (i = 0; i < st_temp->cnt_history; i++)
1512                                 fprintf(fp, "%s\n", st_temp->history[i]);
1513                         fclose(fp);
1514                         if (rename(new_name, state->hist_file) == 0)
1515                                 state->cnt_history_in_file = st_temp->cnt_history;
1516                 }
1517                 free(new_name);
1518                 free_line_input_t(st_temp);
1519         }
1520 }
1521 #  endif
1522 # else
1523 #  define load_history(a) ((void)0)
1524 #  define save_history(a) ((void)0)
1525 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1526
1527 static void remember_in_history(char *str)
1528 {
1529         int i;
1530
1531         if (!(state->flags & DO_HISTORY))
1532                 return;
1533         if (str[0] == '\0')
1534                 return;
1535         i = state->cnt_history;
1536         /* Don't save dupes */
1537         if (i && strcmp(state->history[i-1], str) == 0)
1538                 return;
1539
1540         free(state->history[state->max_history]); /* redundant, paranoia */
1541         state->history[state->max_history] = NULL; /* redundant, paranoia */
1542
1543         /* If history[] is full, remove the oldest command */
1544         /* we need to keep history[state->max_history] empty, hence >=, not > */
1545         if (i >= state->max_history) {
1546                 free(state->history[0]);
1547                 for (i = 0; i < state->max_history-1; i++)
1548                         state->history[i] = state->history[i+1];
1549                 /* i == state->max_history-1 */
1550 # if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1551                 if (state->cnt_history_in_file)
1552                         state->cnt_history_in_file--;
1553 # endif
1554         }
1555         /* i <= state->max_history-1 */
1556         state->history[i++] = xstrdup(str);
1557         /* i <= state->max_history */
1558         state->cur_history = i;
1559         state->cnt_history = i;
1560 # if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1561         save_history(str);
1562 # endif
1563 }
1564
1565 #else /* MAX_HISTORY == 0 */
1566 # define remember_in_history(a) ((void)0)
1567 #endif /* MAX_HISTORY */
1568
1569
1570 #if ENABLE_FEATURE_EDITING_VI
1571 /*
1572  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1573  */
1574 static void
1575 vi_Word_motion(int eat)
1576 {
1577         CHAR_T *command = command_ps;
1578
1579         while (cursor < command_len && !BB_isspace(command[cursor]))
1580                 input_forward();
1581         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1582                 input_forward();
1583 }
1584
1585 static void
1586 vi_word_motion(int eat)
1587 {
1588         CHAR_T *command = command_ps;
1589
1590         if (BB_isalnum_or_underscore(command[cursor])) {
1591                 while (cursor < command_len
1592                  && (BB_isalnum_or_underscore(command[cursor+1]))
1593                 ) {
1594                         input_forward();
1595                 }
1596         } else if (BB_ispunct(command[cursor])) {
1597                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1598                         input_forward();
1599         }
1600
1601         if (cursor < command_len)
1602                 input_forward();
1603
1604         if (eat) {
1605                 while (cursor < command_len && BB_isspace(command[cursor]))
1606                         input_forward();
1607         }
1608 }
1609
1610 static void
1611 vi_End_motion(void)
1612 {
1613         CHAR_T *command = command_ps;
1614
1615         input_forward();
1616         while (cursor < command_len && BB_isspace(command[cursor]))
1617                 input_forward();
1618         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1619                 input_forward();
1620 }
1621
1622 static void
1623 vi_end_motion(void)
1624 {
1625         CHAR_T *command = command_ps;
1626
1627         if (cursor >= command_len-1)
1628                 return;
1629         input_forward();
1630         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1631                 input_forward();
1632         if (cursor >= command_len-1)
1633                 return;
1634         if (BB_isalnum_or_underscore(command[cursor])) {
1635                 while (cursor < command_len-1
1636                  && (BB_isalnum_or_underscore(command[cursor+1]))
1637                 ) {
1638                         input_forward();
1639                 }
1640         } else if (BB_ispunct(command[cursor])) {
1641                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1642                         input_forward();
1643         }
1644 }
1645
1646 static void
1647 vi_Back_motion(void)
1648 {
1649         CHAR_T *command = command_ps;
1650
1651         while (cursor > 0 && BB_isspace(command[cursor-1]))
1652                 input_backward(1);
1653         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1654                 input_backward(1);
1655 }
1656
1657 static void
1658 vi_back_motion(void)
1659 {
1660         CHAR_T *command = command_ps;
1661
1662         if (cursor <= 0)
1663                 return;
1664         input_backward(1);
1665         while (cursor > 0 && BB_isspace(command[cursor]))
1666                 input_backward(1);
1667         if (cursor <= 0)
1668                 return;
1669         if (BB_isalnum_or_underscore(command[cursor])) {
1670                 while (cursor > 0
1671                  && (BB_isalnum_or_underscore(command[cursor-1]))
1672                 ) {
1673                         input_backward(1);
1674                 }
1675         } else if (BB_ispunct(command[cursor])) {
1676                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1677                         input_backward(1);
1678         }
1679 }
1680 #endif
1681
1682 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1683 static void ctrl_left(void)
1684 {
1685         CHAR_T *command = command_ps;
1686
1687         while (1) {
1688                 CHAR_T c;
1689
1690                 input_backward(1);
1691                 if (cursor == 0)
1692                         break;
1693                 c = command[cursor];
1694                 if (c != ' ' && !BB_ispunct(c)) {
1695                         /* we reached a "word" delimited by spaces/punct.
1696                          * go to its beginning */
1697                         while (1) {
1698                                 c = command[cursor - 1];
1699                                 if (c == ' ' || BB_ispunct(c))
1700                                         break;
1701                                 input_backward(1);
1702                                 if (cursor == 0)
1703                                         break;
1704                         }
1705                         break;
1706                 }
1707         }
1708 }
1709 static void ctrl_right(void)
1710 {
1711         CHAR_T *command = command_ps;
1712
1713         while (1) {
1714                 CHAR_T c;
1715
1716                 c = command[cursor];
1717                 if (c == BB_NUL)
1718                         break;
1719                 if (c != ' ' && !BB_ispunct(c)) {
1720                         /* we reached a "word" delimited by spaces/punct.
1721                          * go to its end + 1 */
1722                         while (1) {
1723                                 input_forward();
1724                                 c = command[cursor];
1725                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1726                                         break;
1727                         }
1728                         break;
1729                 }
1730                 input_forward();
1731         }
1732 }
1733
1734
1735 /*
1736  * read_line_input and its helpers
1737  */
1738
1739 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1740 static void ask_terminal(void)
1741 {
1742         /* Ask terminal where is the cursor now.
1743          * lineedit_read_key handles response and corrects
1744          * our idea of current cursor position.
1745          * Testcase: run "echo -n long_line_long_line_long_line",
1746          * then type in a long, wrapping command and try to
1747          * delete it using backspace key.
1748          * Note: we print it _after_ prompt, because
1749          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1750          */
1751         /* Problem: if there is buffered input on stdin,
1752          * the response will be delivered later,
1753          * possibly to an unsuspecting application.
1754          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1755          * Result:
1756          * ~/srcdevel/bbox/fix/busybox.t4 #
1757          * ~/srcdevel/bbox/fix/busybox.t4 #
1758          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1759          * ~/srcdevel/bbox/fix/busybox.t4 #
1760          *
1761          * Checking for input with poll only makes the race narrower,
1762          * I still can trigger it. Strace:
1763          *
1764          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1765          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1766          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1767          * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
1768          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1769          */
1770         struct pollfd pfd;
1771
1772         pfd.fd = STDIN_FILENO;
1773         pfd.events = POLLIN;
1774         if (safe_poll(&pfd, 1, 0) == 0) {
1775                 S.sent_ESC_br6n = 1;
1776                 fputs(ESC"[6n", stdout);
1777                 fflush_all(); /* make terminal see it ASAP! */
1778         }
1779 }
1780 #else
1781 #define ask_terminal() ((void)0)
1782 #endif
1783
1784 /* Called just once at read_line_input() init time */
1785 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1786 static void parse_and_put_prompt(const char *prmt_ptr)
1787 {
1788         const char *p;
1789         cmdedit_prompt = prmt_ptr;
1790         p = strrchr(prmt_ptr, '\n');
1791         cmdedit_prmt_len = unicode_strwidth(p ? p+1 : prmt_ptr);
1792         put_prompt();
1793 }
1794 #else
1795 static void parse_and_put_prompt(const char *prmt_ptr)
1796 {
1797         int prmt_size = 0;
1798         char *prmt_mem_ptr = xzalloc(1);
1799 # if ENABLE_USERNAME_OR_HOMEDIR
1800         char *cwd_buf = NULL;
1801 # endif
1802         char flg_not_length = '[';
1803         char cbuf[2];
1804
1805         /*cmdedit_prmt_len = 0; - already is */
1806
1807         cbuf[1] = '\0'; /* never changes */
1808
1809         while (*prmt_ptr) {
1810                 char timebuf[sizeof("HH:MM:SS")];
1811                 char *free_me = NULL;
1812                 char *pbuf;
1813                 char c;
1814
1815                 pbuf = cbuf;
1816                 c = *prmt_ptr++;
1817                 if (c == '\\') {
1818                         const char *cp;
1819                         int l;
1820 /*
1821  * Supported via bb_process_escape_sequence:
1822  * \a   ASCII bell character (07)
1823  * \e   ASCII escape character (033)
1824  * \n   newline
1825  * \r   carriage return
1826  * \\   backslash
1827  * \nnn char with octal code nnn
1828  * Supported:
1829  * \$   if the effective UID is 0, a #, otherwise a $
1830  * \w   current working directory, with $HOME abbreviated with a tilde
1831  *      Note: we do not support $PROMPT_DIRTRIM=n feature
1832  * \W   basename of the current working directory, with $HOME abbreviated with a tilde
1833  * \h   hostname up to the first '.'
1834  * \H   hostname
1835  * \u   username
1836  * \[   begin a sequence of non-printing characters
1837  * \]   end a sequence of non-printing characters
1838  * \T   current time in 12-hour HH:MM:SS format
1839  * \@   current time in 12-hour am/pm format
1840  * \A   current time in 24-hour HH:MM format
1841  * \t   current time in 24-hour HH:MM:SS format
1842  *      (all of the above work as \A)
1843  * Not supported:
1844  * \!   history number of this command
1845  * \#   command number of this command
1846  * \j   number of jobs currently managed by the shell
1847  * \l   basename of the shell's terminal device name
1848  * \s   name of the shell, the basename of $0 (the portion following the final slash)
1849  * \V   release of bash, version + patch level (e.g., 2.00.0)
1850  * \d   date in "Weekday Month Date" format (e.g., "Tue May 26")
1851  * \D{format}
1852  *      format is passed to strftime(3).
1853  *      An empty format results in a locale-specific time representation.
1854  *      The braces are required.
1855  * Mishandled by bb_process_escape_sequence:
1856  * \v   version of bash (e.g., 2.00)
1857  */
1858                         cp = prmt_ptr;
1859                         c = *cp;
1860                         if (c != 't') /* don't treat \t as tab */
1861                                 c = bb_process_escape_sequence(&prmt_ptr);
1862                         if (prmt_ptr == cp) {
1863                                 if (*cp == '\0')
1864                                         break;
1865                                 c = *prmt_ptr++;
1866
1867                                 switch (c) {
1868 # if ENABLE_USERNAME_OR_HOMEDIR
1869                                 case 'u':
1870                                         pbuf = user_buf ? user_buf : (char*)"";
1871                                         break;
1872 # endif
1873                                 case 'H':
1874                                 case 'h':
1875                                         pbuf = free_me = safe_gethostname();
1876                                         if (c == 'h')
1877                                                 strchrnul(pbuf, '.')[0] = '\0';
1878                                         break;
1879                                 case '$':
1880                                         c = (geteuid() == 0 ? '#' : '$');
1881                                         break;
1882                                 case 'T': /* 12-hour HH:MM:SS format */
1883                                 case '@': /* 12-hour am/pm format */
1884                                 case 'A': /* 24-hour HH:MM format */
1885                                 case 't': /* 24-hour HH:MM:SS format */
1886                                         /* We show all of them as 24-hour HH:MM */
1887                                         strftime_HHMMSS(timebuf, sizeof(timebuf), NULL)[-3] = '\0';
1888                                         pbuf = timebuf;
1889                                         break;
1890 # if ENABLE_USERNAME_OR_HOMEDIR
1891                                 case 'w': /* current dir */
1892                                 case 'W': /* basename of cur dir */
1893                                         if (!cwd_buf) {
1894                                                 cwd_buf = xrealloc_getcwd_or_warn(NULL);
1895                                                 if (!cwd_buf)
1896                                                         cwd_buf = (char *)bb_msg_unknown;
1897                                                 else if (home_pwd_buf[0]) {
1898                                                         char *after_home_user;
1899
1900                                                         /* /home/user[/something] -> ~[/something] */
1901                                                         after_home_user = is_prefixed_with(cwd_buf, home_pwd_buf);
1902                                                         if (after_home_user
1903                                                          && (*after_home_user == '/' || *after_home_user == '\0')
1904                                                         ) {
1905                                                                 cwd_buf[0] = '~';
1906                                                                 overlapping_strcpy(cwd_buf + 1, after_home_user);
1907                                                         }
1908                                                 }
1909                                         }
1910                                         pbuf = cwd_buf;
1911                                         if (c == 'w')
1912                                                 break;
1913                                         cp = strrchr(pbuf, '/');
1914                                         if (cp)
1915                                                 pbuf = (char*)cp + 1;
1916                                         break;
1917 # endif
1918 // bb_process_escape_sequence does this now:
1919 //                              case 'e': case 'E':     /* \e \E = \033 */
1920 //                                      c = '\033';
1921 //                                      break;
1922                                 case 'x': case 'X': {
1923                                         char buf2[4];
1924                                         for (l = 0; l < 3;) {
1925                                                 unsigned h;
1926                                                 buf2[l++] = *prmt_ptr;
1927                                                 buf2[l] = '\0';
1928                                                 h = strtoul(buf2, &pbuf, 16);
1929                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1930                                                         buf2[--l] = '\0';
1931                                                         break;
1932                                                 }
1933                                                 prmt_ptr++;
1934                                         }
1935                                         c = (char)strtoul(buf2, NULL, 16);
1936                                         if (c == 0)
1937                                                 c = '?';
1938                                         pbuf = cbuf;
1939                                         break;
1940                                 }
1941                                 case '[': case ']':
1942                                         if (c == flg_not_length) {
1943                                                 /* Toggle '['/']' hex 5b/5d */
1944                                                 flg_not_length ^= 6;
1945                                                 continue;
1946                                         }
1947                                         break;
1948                                 } /* switch */
1949                         } /* if */
1950                 } /* if */
1951                 cbuf[0] = c;
1952                 {
1953                         int n = strlen(pbuf);
1954                         prmt_size += n;
1955                         if (c == '\n')
1956                                 cmdedit_prmt_len = 0;
1957                         else if (flg_not_length != ']') {
1958 #if 0 /*ENABLE_UNICODE_SUPPORT*/
1959 /* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
1960 /* FIXME */
1961                                 cmdedit_prmt_len += unicode_strwidth(pbuf);
1962 #else
1963                                 cmdedit_prmt_len += n;
1964 #endif
1965                         }
1966                 }
1967                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_size+1), pbuf);
1968                 free(free_me);
1969         } /* while */
1970
1971 # if ENABLE_USERNAME_OR_HOMEDIR
1972         if (cwd_buf != (char *)bb_msg_unknown)
1973                 free(cwd_buf);
1974 # endif
1975         cmdedit_prompt = prmt_mem_ptr;
1976         put_prompt();
1977 }
1978 #endif
1979
1980 static void cmdedit_setwidth(void)
1981 {
1982         int new_y;
1983
1984         cmdedit_termw = get_terminal_width(STDIN_FILENO);
1985         /* new y for current cursor */
1986         new_y = (cursor + cmdedit_prmt_len) / cmdedit_termw;
1987         /* redraw */
1988         redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1989 }
1990
1991 static void win_changed(int nsig UNUSED_PARAM)
1992 {
1993         if (S.ok_to_redraw) {
1994                 /* We are in read_key(), safe to redraw immediately */
1995                 int sv_errno = errno;
1996                 cmdedit_setwidth();
1997                 fflush_all();
1998                 errno = sv_errno;
1999         } else {
2000                 /* Signal main loop that redraw is necessary */
2001                 S.SIGWINCH_count++;
2002         }
2003 }
2004
2005 static int lineedit_read_key(char *read_key_buffer, int timeout)
2006 {
2007         int64_t ic;
2008 #if ENABLE_UNICODE_SUPPORT
2009         char unicode_buf[MB_CUR_MAX + 1];
2010         int unicode_idx = 0;
2011 #endif
2012
2013         fflush_all();
2014         while (1) {
2015                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
2016                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
2017                  * insist on full MB_CUR_MAX buffer to declare input like
2018                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
2019                  *
2020                  * Note: read_key sets errno to 0 on success.
2021                  */
2022                 S.ok_to_redraw = 1;
2023                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
2024                 S.ok_to_redraw = 0;
2025                 if (errno) {
2026 #if ENABLE_UNICODE_SUPPORT
2027                         if (errno == EAGAIN && unicode_idx != 0)
2028                                 goto pushback;
2029 #endif
2030                         break;
2031                 }
2032
2033 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2034                 if ((int32_t)ic == KEYCODE_CURSOR_POS
2035                  && S.sent_ESC_br6n
2036                 ) {
2037                         S.sent_ESC_br6n = 0;
2038                         if (cursor == 0) { /* otherwise it may be bogus */
2039                                 int col = ((ic >> 32) & 0x7fff) - 1;
2040                                 /*
2041                                  * Is col > cmdedit_prmt_len?
2042                                  * If yes (terminal says cursor is farther to the right
2043                                  * of where we think it should be),
2044                                  * the prompt wasn't printed starting at col 1,
2045                                  * there was additional text before it.
2046                                  */
2047                                 if ((int)(col - cmdedit_prmt_len) > 0) {
2048                                         /* Fix our understanding of current x position */
2049                                         cmdedit_x += (col - cmdedit_prmt_len);
2050                                         while (cmdedit_x >= cmdedit_termw) {
2051                                                 cmdedit_x -= cmdedit_termw;
2052                                                 cmdedit_y++;
2053                                         }
2054                                 }
2055                         }
2056                         continue;
2057                 }
2058 #endif
2059
2060 #if ENABLE_UNICODE_SUPPORT
2061                 if (unicode_status == UNICODE_ON) {
2062                         wchar_t wc;
2063
2064                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
2065                                 break;
2066                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
2067
2068                         unicode_buf[unicode_idx++] = ic;
2069                         unicode_buf[unicode_idx] = '\0';
2070                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
2071                                 /* Not (yet?) a valid unicode char */
2072                                 if (unicode_idx < MB_CUR_MAX) {
2073                                         timeout = 50;
2074                                         continue;
2075                                 }
2076  pushback:
2077                                 /* Invalid sequence. Save all "bad bytes" except first */
2078                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
2079 # if !ENABLE_UNICODE_PRESERVE_BROKEN
2080                                 ic = CONFIG_SUBST_WCHAR;
2081 # else
2082                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
2083 # endif
2084                         } else {
2085                                 /* Valid unicode char, return its code */
2086                                 ic = wc;
2087                         }
2088                 }
2089 #endif
2090                 break;
2091         }
2092
2093         return ic;
2094 }
2095
2096 #if ENABLE_UNICODE_BIDI_SUPPORT
2097 static int isrtl_str(void)
2098 {
2099         int idx = cursor;
2100
2101         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
2102                 idx++;
2103         return unicode_bidi_isrtl(command_ps[idx]);
2104 }
2105 #else
2106 # define isrtl_str() 0
2107 #endif
2108
2109 /* leave out the "vi-mode"-only case labels if vi editing isn't
2110  * configured. */
2111 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
2112
2113 /* convert uppercase ascii to equivalent control char, for readability */
2114 #undef CTRL
2115 #define CTRL(a) ((a) & ~0x40)
2116
2117 enum {
2118         VI_CMDMODE_BIT = 0x40000000,
2119         /* 0x80000000 bit flags KEYCODE_xxx */
2120 };
2121
2122 #if ENABLE_FEATURE_REVERSE_SEARCH
2123 /* Mimic readline Ctrl-R reverse history search.
2124  * When invoked, it shows the following prompt:
2125  * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
2126  * and typing results in search being performed:
2127  * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
2128  * Search is performed by looking at progressively older lines in history.
2129  * Ctrl-R again searches for the next match in history.
2130  * Backspace deletes last matched char.
2131  * Control keys exit search and return to normal editing (at current history line).
2132  */
2133 static int32_t reverse_i_search(void)
2134 {
2135         char match_buf[128]; /* for user input */
2136         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2137         const char *matched_history_line;
2138         const char *saved_prompt;
2139         unsigned saved_prmt_len;
2140         int32_t ic;
2141
2142         matched_history_line = NULL;
2143         read_key_buffer[0] = 0;
2144         match_buf[0] = '\0';
2145
2146         /* Save and replace the prompt */
2147         saved_prompt = cmdedit_prompt;
2148         saved_prmt_len = cmdedit_prmt_len;
2149         goto set_prompt;
2150
2151         while (1) {
2152                 int h;
2153                 unsigned match_buf_len = strlen(match_buf);
2154
2155 //FIXME: correct timeout?
2156                 ic = lineedit_read_key(read_key_buffer, -1);
2157
2158                 switch (ic) {
2159                 case CTRL('R'): /* searching for the next match */
2160                         break;
2161
2162                 case '\b':
2163                 case '\x7f':
2164                         /* Backspace */
2165                         if (unicode_status == UNICODE_ON) {
2166                                 while (match_buf_len != 0) {
2167                                         uint8_t c = match_buf[--match_buf_len];
2168                                         if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
2169                                                 break; /* yes */
2170                                 }
2171                         } else {
2172                                 if (match_buf_len != 0)
2173                                         match_buf_len--;
2174                         }
2175                         match_buf[match_buf_len] = '\0';
2176                         break;
2177
2178                 default:
2179                         if (ic < ' '
2180                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2181                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2182                         ) {
2183                                 goto ret;
2184                         }
2185
2186                         /* Append this char */
2187 #if ENABLE_UNICODE_SUPPORT
2188                         if (unicode_status == UNICODE_ON) {
2189                                 mbstate_t mbstate = { 0 };
2190                                 char buf[MB_CUR_MAX + 1];
2191                                 int len = wcrtomb(buf, ic, &mbstate);
2192                                 if (len > 0) {
2193                                         buf[len] = '\0';
2194                                         if (match_buf_len + len < sizeof(match_buf))
2195                                                 strcpy(match_buf + match_buf_len, buf);
2196                                 }
2197                         } else
2198 #endif
2199                         if (match_buf_len < sizeof(match_buf) - 1) {
2200                                 match_buf[match_buf_len] = ic;
2201                                 match_buf[match_buf_len + 1] = '\0';
2202                         }
2203                         break;
2204                 } /* switch (ic) */
2205
2206                 /* Search in history for match_buf */
2207                 h = state->cur_history;
2208                 if (ic == CTRL('R'))
2209                         h--;
2210                 while (h >= 0) {
2211                         if (state->history[h]) {
2212                                 char *match = strstr(state->history[h], match_buf);
2213                                 if (match) {
2214                                         state->cur_history = h;
2215                                         matched_history_line = state->history[h];
2216                                         command_len = load_string(matched_history_line);
2217                                         cursor = match - matched_history_line;
2218 //FIXME: cursor position for Unicode case
2219
2220                                         free((char*)cmdedit_prompt);
2221  set_prompt:
2222                                         cmdedit_prompt = xasprintf("(reverse-i-search)'%s': ", match_buf);
2223                                         cmdedit_prmt_len = unicode_strwidth(cmdedit_prompt);
2224                                         goto do_redraw;
2225                                 }
2226                         }
2227                         h--;
2228                 }
2229
2230                 /* Not found */
2231                 match_buf[match_buf_len] = '\0';
2232                 beep();
2233                 continue;
2234
2235  do_redraw:
2236                 redraw(cmdedit_y, command_len - cursor);
2237         } /* while (1) */
2238
2239  ret:
2240         if (matched_history_line)
2241                 command_len = load_string(matched_history_line);
2242
2243         free((char*)cmdedit_prompt);
2244         cmdedit_prompt = saved_prompt;
2245         cmdedit_prmt_len = saved_prmt_len;
2246         redraw(cmdedit_y, command_len - cursor);
2247
2248         return ic;
2249 }
2250 #endif
2251
2252 /* maxsize must be >= 2.
2253  * Returns:
2254  * -1 on read errors or EOF, or on bare Ctrl-D,
2255  * 0  on ctrl-C (the line entered is still returned in 'command'),
2256  * (in both cases the cursor remains on the input line, '\n' is not printed)
2257  * >0 length of input string, including terminating '\n'
2258  */
2259 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize, int timeout)
2260 {
2261         int len;
2262 #if ENABLE_FEATURE_TAB_COMPLETION
2263         smallint lastWasTab = 0;
2264 #endif
2265         smallint break_out = 0;
2266 #if ENABLE_FEATURE_EDITING_VI
2267         smallint vi_cmdmode = 0;
2268 #endif
2269         struct termios initial_settings;
2270         struct termios new_settings;
2271         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2272
2273         INIT_S();
2274
2275         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
2276          || (initial_settings.c_lflag & (ECHO|ICANON)) == ICANON
2277         ) {
2278                 /* Happens when e.g. stty -echo was run before.
2279                  * But if ICANON is not set, we don't come here.
2280                  * (example: interactive python ^Z-backgrounded,
2281                  * tty is still in "raw mode").
2282                  */
2283                 parse_and_put_prompt(prompt);
2284                 fflush_all();
2285                 if (fgets(command, maxsize, stdin) == NULL)
2286                         len = -1; /* EOF or error */
2287                 else
2288                         len = strlen(command);
2289                 DEINIT_S();
2290                 return len;
2291         }
2292
2293         init_unicode();
2294
2295 // FIXME: audit & improve this
2296         if (maxsize > MAX_LINELEN)
2297                 maxsize = MAX_LINELEN;
2298         S.maxsize = maxsize;
2299
2300         /* With zero flags, no other fields are ever used */
2301         state = st ? st : (line_input_t*) &const_int_0;
2302 #if MAX_HISTORY > 0
2303 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
2304         if (state->hist_file)
2305                 if (state->cnt_history == 0)
2306                         load_history(state);
2307 # endif
2308         if (state->flags & DO_HISTORY)
2309                 state->cur_history = state->cnt_history;
2310 #endif
2311
2312         /* prepare before init handlers */
2313         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
2314         command_len = 0;
2315 #if ENABLE_UNICODE_SUPPORT
2316         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
2317 #else
2318         command_ps = command;
2319         command[0] = '\0';
2320 #endif
2321 #define command command_must_not_be_used
2322
2323         new_settings = initial_settings;
2324         /* ~ICANON: unbuffered input (most c_cc[] are disabled, VMIN/VTIME are enabled) */
2325         /* ~ECHO, ~ECHONL: turn off echoing, including newline echoing */
2326         /* ~ISIG: turn off INTR (ctrl-C), QUIT, SUSP */
2327         new_settings.c_lflag &= ~(ICANON | ECHO | ECHONL | ISIG);
2328         /* reads will block only if < 1 char is available */
2329         new_settings.c_cc[VMIN] = 1;
2330         /* no timeout (reads block forever) */
2331         new_settings.c_cc[VTIME] = 0;
2332         /* Should be not needed if ISIG is off: */
2333         /* Turn off CTRL-C */
2334         /* new_settings.c_cc[VINTR] = _POSIX_VDISABLE; */
2335         tcsetattr_stdin_TCSANOW(&new_settings);
2336
2337 #if ENABLE_USERNAME_OR_HOMEDIR
2338         {
2339                 struct passwd *entry;
2340
2341                 entry = getpwuid(geteuid());
2342                 if (entry) {
2343                         user_buf = xstrdup(entry->pw_name);
2344                         home_pwd_buf = xstrdup(entry->pw_dir);
2345                 }
2346         }
2347 #endif
2348
2349 #if 0
2350         for (i = 0; i <= state->max_history; i++)
2351                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2352         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2353 #endif
2354
2355         /* Print out the command prompt, optionally ask where cursor is */
2356         parse_and_put_prompt(prompt);
2357         ask_terminal();
2358
2359         /* Install window resize handler (NB: after *all* init is complete) */
2360         S.SIGWINCH_handler.sa_handler = win_changed;
2361         S.SIGWINCH_handler.sa_flags = SA_RESTART;
2362         sigaction(SIGWINCH, &S.SIGWINCH_handler, &S.SIGWINCH_handler);
2363
2364         cmdedit_termw = get_terminal_width(STDIN_FILENO);
2365
2366         read_key_buffer[0] = 0;
2367         while (1) {
2368                 /*
2369                  * The emacs and vi modes share much of the code in the big
2370                  * command loop.  Commands entered when in vi's command mode
2371                  * (aka "escape mode") get an extra bit added to distinguish
2372                  * them - this keeps them from being self-inserted. This
2373                  * clutters the big switch a bit, but keeps all the code
2374                  * in one place.
2375                  */
2376                 int32_t ic, ic_raw;
2377                 unsigned count;
2378
2379                 count = S.SIGWINCH_count;
2380                 if (S.SIGWINCH_saved != count) {
2381                         S.SIGWINCH_saved = count;
2382                         cmdedit_setwidth();
2383                 }
2384
2385                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2386
2387 #if ENABLE_FEATURE_REVERSE_SEARCH
2388  again:
2389 #endif
2390 #if ENABLE_FEATURE_EDITING_VI
2391                 newdelflag = 1;
2392                 if (vi_cmdmode) {
2393                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2394                          * change ic if it contains one of them: */
2395                         ic |= VI_CMDMODE_BIT;
2396                 }
2397 #endif
2398
2399                 switch (ic) {
2400                 case '\n':
2401                 case '\r':
2402                 vi_case('\n'|VI_CMDMODE_BIT:)
2403                 vi_case('\r'|VI_CMDMODE_BIT:)
2404                         /* Enter */
2405                         goto_new_line();
2406                         break_out = 1;
2407                         break;
2408                 case CTRL('A'):
2409                 vi_case('0'|VI_CMDMODE_BIT:)
2410                         /* Control-a -- Beginning of line */
2411                         input_backward(cursor);
2412                         break;
2413                 case CTRL('B'):
2414                 vi_case('h'|VI_CMDMODE_BIT:)
2415                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2416                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2417                         input_backward(1); /* Move back one character */
2418                         break;
2419                 case CTRL('E'):
2420                 vi_case('$'|VI_CMDMODE_BIT:)
2421                         /* Control-e -- End of line */
2422                         put_till_end_and_adv_cursor();
2423                         break;
2424                 case CTRL('F'):
2425                 vi_case('l'|VI_CMDMODE_BIT:)
2426                 vi_case(' '|VI_CMDMODE_BIT:)
2427                         input_forward(); /* Move forward one character */
2428                         break;
2429                 case '\b':   /* ^H */
2430                 case '\x7f': /* DEL */
2431                         if (!isrtl_str())
2432                                 input_backspace();
2433                         else
2434                                 input_delete(0);
2435                         break;
2436                 case KEYCODE_DELETE:
2437                         if (!isrtl_str())
2438                                 input_delete(0);
2439                         else
2440                                 input_backspace();
2441                         break;
2442 #if ENABLE_FEATURE_TAB_COMPLETION
2443                 case '\t':
2444                         input_tab(&lastWasTab);
2445                         break;
2446 #endif
2447                 case CTRL('K'):
2448                         /* Control-k -- clear to end of line */
2449                         command_ps[cursor] = BB_NUL;
2450                         command_len = cursor;
2451                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2452                         break;
2453                 case CTRL('L'):
2454                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2455                         /* Control-l -- clear screen */
2456                         printf(ESC"[H"); /* cursor to top,left */
2457                         redraw(0, command_len - cursor);
2458                         break;
2459 #if MAX_HISTORY > 0
2460                 case CTRL('N'):
2461                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2462                 vi_case('j'|VI_CMDMODE_BIT:)
2463                         /* Control-n -- Get next command in history */
2464                         if (get_next_history())
2465                                 goto rewrite_line;
2466                         break;
2467                 case CTRL('P'):
2468                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2469                 vi_case('k'|VI_CMDMODE_BIT:)
2470                         /* Control-p -- Get previous command from history */
2471                         if (get_previous_history())
2472                                 goto rewrite_line;
2473                         break;
2474 #endif
2475                 case CTRL('U'):
2476                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2477                         /* Control-U -- Clear line before cursor */
2478                         if (cursor) {
2479                                 command_len -= cursor;
2480                                 memmove(command_ps, command_ps + cursor,
2481                                         (command_len + 1) * sizeof(command_ps[0]));
2482                                 redraw(cmdedit_y, command_len);
2483                         }
2484                         break;
2485                 case CTRL('W'):
2486                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2487                         /* Control-W -- Remove the last word */
2488                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2489                                 input_backspace();
2490                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2491                                 input_backspace();
2492                         break;
2493                 case KEYCODE_ALT_D: {
2494                         /* Delete word forward */
2495                         int nc, sc = cursor;
2496                         ctrl_right();
2497                         nc = cursor - sc;
2498                         input_backward(nc);
2499                         while (--nc >= 0)
2500                                 input_delete(1);
2501                         break;
2502                 }
2503                 case KEYCODE_ALT_BACKSPACE: {
2504                         /* Delete word backward */
2505                         int sc = cursor;
2506                         ctrl_left();
2507                         while (sc-- > cursor)
2508                                 input_delete(1);
2509                         break;
2510                 }
2511 #if ENABLE_FEATURE_REVERSE_SEARCH
2512                 case CTRL('R'):
2513                         ic = ic_raw = reverse_i_search();
2514                         goto again;
2515 #endif
2516
2517 #if ENABLE_FEATURE_EDITING_VI
2518                 case 'i'|VI_CMDMODE_BIT:
2519                         vi_cmdmode = 0;
2520                         break;
2521                 case 'I'|VI_CMDMODE_BIT:
2522                         input_backward(cursor);
2523                         vi_cmdmode = 0;
2524                         break;
2525                 case 'a'|VI_CMDMODE_BIT:
2526                         input_forward();
2527                         vi_cmdmode = 0;
2528                         break;
2529                 case 'A'|VI_CMDMODE_BIT:
2530                         put_till_end_and_adv_cursor();
2531                         vi_cmdmode = 0;
2532                         break;
2533                 case 'x'|VI_CMDMODE_BIT:
2534                         input_delete(1);
2535                         break;
2536                 case 'X'|VI_CMDMODE_BIT:
2537                         if (cursor > 0) {
2538                                 input_backward(1);
2539                                 input_delete(1);
2540                         }
2541                         break;
2542                 case 'W'|VI_CMDMODE_BIT:
2543                         vi_Word_motion(1);
2544                         break;
2545                 case 'w'|VI_CMDMODE_BIT:
2546                         vi_word_motion(1);
2547                         break;
2548                 case 'E'|VI_CMDMODE_BIT:
2549                         vi_End_motion();
2550                         break;
2551                 case 'e'|VI_CMDMODE_BIT:
2552                         vi_end_motion();
2553                         break;
2554                 case 'B'|VI_CMDMODE_BIT:
2555                         vi_Back_motion();
2556                         break;
2557                 case 'b'|VI_CMDMODE_BIT:
2558                         vi_back_motion();
2559                         break;
2560                 case 'C'|VI_CMDMODE_BIT:
2561                         vi_cmdmode = 0;
2562                         /* fall through */
2563                 case 'D'|VI_CMDMODE_BIT:
2564                         goto clear_to_eol;
2565
2566                 case 'c'|VI_CMDMODE_BIT:
2567                         vi_cmdmode = 0;
2568                         /* fall through */
2569                 case 'd'|VI_CMDMODE_BIT: {
2570                         int nc, sc;
2571
2572                         ic = lineedit_read_key(read_key_buffer, timeout);
2573                         if (errno) /* error */
2574                                 goto return_error_indicator;
2575                         if (ic == ic_raw) { /* "cc", "dd" */
2576                                 input_backward(cursor);
2577                                 goto clear_to_eol;
2578                                 break;
2579                         }
2580
2581                         sc = cursor;
2582                         switch (ic) {
2583                         case 'w':
2584                         case 'W':
2585                         case 'e':
2586                         case 'E':
2587                                 switch (ic) {
2588                                 case 'w':   /* "dw", "cw" */
2589                                         vi_word_motion(vi_cmdmode);
2590                                         break;
2591                                 case 'W':   /* 'dW', 'cW' */
2592                                         vi_Word_motion(vi_cmdmode);
2593                                         break;
2594                                 case 'e':   /* 'de', 'ce' */
2595                                         vi_end_motion();
2596                                         input_forward();
2597                                         break;
2598                                 case 'E':   /* 'dE', 'cE' */
2599                                         vi_End_motion();
2600                                         input_forward();
2601                                         break;
2602                                 }
2603                                 nc = cursor;
2604                                 input_backward(cursor - sc);
2605                                 while (nc-- > cursor)
2606                                         input_delete(1);
2607                                 break;
2608                         case 'b':  /* "db", "cb" */
2609                         case 'B':  /* implemented as B */
2610                                 if (ic == 'b')
2611                                         vi_back_motion();
2612                                 else
2613                                         vi_Back_motion();
2614                                 while (sc-- > cursor)
2615                                         input_delete(1);
2616                                 break;
2617                         case ' ':  /* "d ", "c " */
2618                                 input_delete(1);
2619                                 break;
2620                         case '$':  /* "d$", "c$" */
2621  clear_to_eol:
2622                                 while (cursor < command_len)
2623                                         input_delete(1);
2624                                 break;
2625                         }
2626                         break;
2627                 }
2628                 case 'p'|VI_CMDMODE_BIT:
2629                         input_forward();
2630                         /* fallthrough */
2631                 case 'P'|VI_CMDMODE_BIT:
2632                         put();
2633                         break;
2634                 case 'r'|VI_CMDMODE_BIT:
2635 //FIXME: unicode case?
2636                         ic = lineedit_read_key(read_key_buffer, timeout);
2637                         if (errno) /* error */
2638                                 goto return_error_indicator;
2639                         if (ic < ' ' || ic > 255) {
2640                                 beep();
2641                         } else {
2642                                 command_ps[cursor] = ic;
2643                                 bb_putchar(ic);
2644                                 bb_putchar('\b');
2645                         }
2646                         break;
2647                 case '\x1b': /* ESC */
2648                         if (state->flags & VI_MODE) {
2649                                 /* insert mode --> command mode */
2650                                 vi_cmdmode = 1;
2651                                 input_backward(1);
2652                         }
2653                         break;
2654 #endif /* FEATURE_COMMAND_EDITING_VI */
2655
2656 #if MAX_HISTORY > 0
2657                 case KEYCODE_UP:
2658                         if (get_previous_history())
2659                                 goto rewrite_line;
2660                         beep();
2661                         break;
2662                 case KEYCODE_DOWN:
2663                         if (!get_next_history())
2664                                 break;
2665  rewrite_line:
2666                         /* Rewrite the line with the selected history item */
2667                         /* change command */
2668                         command_len = load_string(state->history[state->cur_history] ?
2669                                         state->history[state->cur_history] : "");
2670                         /* redraw and go to eol (bol, in vi) */
2671                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2672                         break;
2673 #endif
2674                 case KEYCODE_RIGHT:
2675                         input_forward();
2676                         break;
2677                 case KEYCODE_LEFT:
2678                         input_backward(1);
2679                         break;
2680                 case KEYCODE_CTRL_LEFT:
2681                 case KEYCODE_ALT_LEFT: /* bash doesn't do it */
2682                         ctrl_left();
2683                         break;
2684                 case KEYCODE_CTRL_RIGHT:
2685                 case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
2686                         ctrl_right();
2687                         break;
2688                 case KEYCODE_HOME:
2689                         input_backward(cursor);
2690                         break;
2691                 case KEYCODE_END:
2692                         put_till_end_and_adv_cursor();
2693                         break;
2694
2695                 default:
2696                         if (initial_settings.c_cc[VINTR] != 0
2697                          && ic_raw == initial_settings.c_cc[VINTR]
2698                         ) {
2699                                 /* Ctrl-C (usually) - stop gathering input */
2700                                 command_len = 0;
2701                                 break_out = -1; /* "do not append '\n'" */
2702                                 break;
2703                         }
2704                         if (initial_settings.c_cc[VEOF] != 0
2705                          && ic_raw == initial_settings.c_cc[VEOF]
2706                         ) {
2707                                 /* Ctrl-D (usually) - delete one character,
2708                                  * or exit if len=0 and no chars to delete */
2709                                 if (command_len == 0) {
2710                                         errno = 0;
2711
2712                 case -1: /* error (e.g. EIO when tty is destroyed) */
2713  IF_FEATURE_EDITING_VI(return_error_indicator:)
2714                                         break_out = command_len = -1;
2715                                         break;
2716                                 }
2717                                 input_delete(0);
2718                                 break;
2719                         }
2720 //                      /* Control-V -- force insert of next char */
2721 //                      if (c == CTRL('V')) {
2722 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2723 //                                      goto return_error_indicator;
2724 //                              if (c == 0) {
2725 //                                      beep();
2726 //                                      break;
2727 //                              }
2728 //                      }
2729                         if (ic < ' '
2730                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2731                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2732                         ) {
2733                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2734                                  * and vi mode ignores unexpected chars.
2735                                  * Otherwise, we are here if ic is a
2736                                  * control char or an unhandled ESC sequence,
2737                                  * which is also ignored.
2738                                  */
2739                                 break;
2740                         }
2741                         if ((int)command_len >= (maxsize - 2)) {
2742                                 /* Not enough space for the char and EOL */
2743                                 break;
2744                         }
2745
2746                         command_len++;
2747                         if (cursor == (command_len - 1)) {
2748                                 /* We are at the end, append */
2749                                 command_ps[cursor] = ic;
2750                                 command_ps[cursor + 1] = BB_NUL;
2751                                 put_cur_glyph_and_inc_cursor();
2752                                 if (unicode_bidi_isrtl(ic))
2753                                         input_backward(1);
2754                         } else {
2755                                 /* In the middle, insert */
2756                                 int sc = cursor;
2757
2758                                 memmove(command_ps + sc + 1, command_ps + sc,
2759                                         (command_len - sc) * sizeof(command_ps[0]));
2760                                 command_ps[sc] = ic;
2761                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2762                                 if (!isrtl_str())
2763                                         sc++; /* no */
2764                                 put_till_end_and_adv_cursor();
2765                                 /* to prev x pos + 1 */
2766                                 input_backward(cursor - sc);
2767                         }
2768                         break;
2769                 } /* switch (ic) */
2770
2771                 if (break_out)
2772                         break;
2773
2774 #if ENABLE_FEATURE_TAB_COMPLETION
2775                 if (ic_raw != '\t')
2776                         lastWasTab = 0;
2777 #endif
2778         } /* while (1) */
2779
2780 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2781         if (S.sent_ESC_br6n) {
2782                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2783                  * We sent "ESC [ 6 n", but got '\n' first, and
2784                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2785                  * It's bad already and not much can be done with it
2786                  * (it _will_ be visible for the next process to read stdin),
2787                  * but without this delay it even shows up on the screen
2788                  * as garbage because we restore echo settings with tcsetattr
2789                  * before it comes in. UGLY!
2790                  */
2791                 usleep(20*1000);
2792         }
2793 #endif
2794
2795 /* End of bug-catching "command_must_not_be_used" trick */
2796 #undef command
2797
2798 #if ENABLE_UNICODE_SUPPORT
2799         command[0] = '\0';
2800         if (command_len > 0)
2801                 command_len = save_string(command, maxsize - 1);
2802         free(command_ps);
2803 #endif
2804
2805         if (command_len > 0) {
2806                 remember_in_history(command);
2807         }
2808
2809         if (break_out > 0) {
2810                 command[command_len++] = '\n';
2811                 command[command_len] = '\0';
2812         }
2813
2814 #if ENABLE_FEATURE_TAB_COMPLETION
2815         free_tab_completion_data();
2816 #endif
2817
2818         /* restore initial_settings */
2819         tcsetattr_stdin_TCSANOW(&initial_settings);
2820         /* restore SIGWINCH handler */
2821         sigaction_set(SIGWINCH, &S.SIGWINCH_handler);
2822         fflush_all();
2823
2824         len = command_len;
2825         DEINIT_S();
2826
2827         return len; /* can't return command_len, DEINIT_S() destroys it */
2828 }
2829
2830 #else  /* !FEATURE_EDITING */
2831
2832 #undef read_line_input
2833 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2834 {
2835         fputs(prompt, stdout);
2836         fflush_all();
2837         if (!fgets(command, maxsize, stdin))
2838                 return -1;
2839         return strlen(command);
2840 }
2841
2842 #endif  /* !FEATURE_EDITING */
2843
2844
2845 /*
2846  * Testing
2847  */
2848
2849 #ifdef TEST
2850
2851 #include <locale.h>
2852
2853 const char *applet_name = "debug stuff usage";
2854
2855 int main(int argc, char **argv)
2856 {
2857         char buff[MAX_LINELEN];
2858         char *prompt =
2859 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2860                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2861                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2862                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2863 #else
2864                 "% ";
2865 #endif
2866
2867         while (1) {
2868                 int l;
2869                 l = read_line_input(prompt, buff);
2870                 if (l <= 0 || buff[l-1] != '\n')
2871                         break;
2872                 buff[l-1] = '\0';
2873                 printf("*** read_line_input() returned line =%s=\n", buff);
2874         }
2875         printf("*** read_line_input() detect ^D\n");
2876         return 0;
2877 }
2878
2879 #endif  /* TEST */