libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16
  17 /*
  18  * Usage and known bugs:
  19  * Terminal key codes are not extensive, more needs to be added.
  20  * This version was created on Debian GNU/Linux 2.x.
  21  * Delete, Backspace, Home, End, and the arrow keys were tested
  22  * to work in an Xterm and console. Ctrl-A also works as Home.
  23  * Ctrl-E also works as End.
  24  *
  25  * The following readline-like commands are not implemented:
  26  * ESC-b -- Move back one word
  27  * ESC-f -- Move forward one word
  28  * ESC-d -- Delete forward one word
  29  * CTL-t -- Transpose two characters
  30  *
  31  * lineedit does not know that the terminal escape sequences do not
  32  * take up space on the screen. The redisplay code assumes, unless
  33  * told otherwise, that each character in the prompt is a printable
  34  * character that takes up one character position on the screen.
  35  * You need to tell lineedit that some sequences of characters
  36  * in the prompt take up no screen space. Compatibly with readline,
  37  * use the \[ escape to begin a sequence of non-printing characters,
  38  * and the \] escape to signal the end of such a sequence. Example:
  39  *
  40  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  41  *
  42  * Unicode in PS1 is not fully supported: prompt length calulation is wrong,
  43  * resulting in line wrap problems with long (multi-line) input.
  44  *
  45  * Multi-line PS1 (e.g. PS1="\n[\w]\n$ ") has problems with history
  46  * browsing: up/down arrows result in scrolling.
  47  * It stems from simplistic "cmdedit_y = cmdedit_prmt_len / cmdedit_termw"
  48  * calculation of how many lines the prompt takes.
  49  */
  50 #include "busybox.h"
  51 #include "NUM_APPLETS.h"
  52 #include "unicode.h"
  53 #ifndef _POSIX_VDISABLE
  54 # define _POSIX_VDISABLE '\0'
  55 #endif
  56
  57
  58 #ifdef TEST
  59 # define ENABLE_FEATURE_EDITING 0
  60 # define ENABLE_FEATURE_TAB_COMPLETION 0
  61 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  62 #endif
  63
  64
  65 /* Entire file (except TESTing part) sits inside this #if */
  66 #if ENABLE_FEATURE_EDITING
  67
  68
  69 #define ENABLE_USERNAME_OR_HOMEDIR \
  70         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  71 #define IF_USERNAME_OR_HOMEDIR(...)
  72 #if ENABLE_USERNAME_OR_HOMEDIR
  73 # undef IF_USERNAME_OR_HOMEDIR
  74 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  75 #endif
  76
  77
  78 #undef CHAR_T
  79 #if ENABLE_UNICODE_SUPPORT
  80 # define BB_NUL ((wchar_t)0)
  81 # define CHAR_T wchar_t
  82 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  83 # if ENABLE_FEATURE_EDITING_VI
  84 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  85 # endif
  86 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  87 # undef isspace
  88 # undef isalnum
  89 # undef ispunct
  90 # undef isprint
  91 # define isspace isspace_must_not_be_used
  92 # define isalnum isalnum_must_not_be_used
  93 # define ispunct ispunct_must_not_be_used
  94 # define isprint isprint_must_not_be_used
  95 #else
  96 # define BB_NUL '\0'
  97 # define CHAR_T char
  98 # define BB_isspace(c) isspace(c)
  99 # define BB_isalnum(c) isalnum(c)
 100 # define BB_ispunct(c) ispunct(c)
 101 #endif
 102 #if ENABLE_UNICODE_PRESERVE_BROKEN
 103 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
 104 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
 105 #else
 106 # define unicode_is_raw_byte(wc)     0
 107 #endif
 108
 109
 110 #define ESC "\033"
 111
 112 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 113 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 114
 115
 116 enum {
 117         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 118                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 119                       : 0x7ff0
 120 };
 121
 122 #if ENABLE_USERNAME_OR_HOMEDIR
 123 static const char null_str[] ALIGN1 = "";
 124 #endif
 125
 126 /* We try to minimize both static and stack usage. */
 127 struct lineedit_statics {
 128         line_input_t *state;
 129
 130         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 131         sighandler_t previous_SIGWINCH_handler;
 132
 133         unsigned cmdedit_x;        /* real x (col) terminal position */
 134         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 135         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 136
 137         unsigned cursor;
 138         int command_len; /* must be signed */
 139         /* signed maxsize: we want x in "if (x > S.maxsize)"
 140          * to _not_ be promoted to unsigned */
 141         int maxsize;
 142         CHAR_T *command_ps;
 143
 144         const char *cmdedit_prompt;
 145
 146 #if ENABLE_USERNAME_OR_HOMEDIR
 147         char *user_buf;
 148         char *home_pwd_buf; /* = (char*)null_str; */
 149 #endif
 150
 151 #if ENABLE_FEATURE_TAB_COMPLETION
 152         char **matches;
 153         unsigned num_matches;
 154 #endif
 155
 156 #if ENABLE_FEATURE_EDITING_VI
 157 # define DELBUFSIZ 128
 158         CHAR_T *delptr;
 159         smallint newdelflag;     /* whether delbuf should be reused yet */
 160         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 161 #endif
 162 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 163         smallint sent_ESC_br6n;
 164 #endif
 165 };
 166
 167 /* See lineedit_ptr_hack.c */
 168 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 169
 170 #define S (*lineedit_ptr_to_statics)
 171 #define state            (S.state           )
 172 #define cmdedit_termw    (S.cmdedit_termw   )
 173 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 174 #define cmdedit_x        (S.cmdedit_x       )
 175 #define cmdedit_y        (S.cmdedit_y       )
 176 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 177 #define cursor           (S.cursor          )
 178 #define command_len      (S.command_len     )
 179 #define command_ps       (S.command_ps      )
 180 #define cmdedit_prompt   (S.cmdedit_prompt  )
 181 #define user_buf         (S.user_buf        )
 182 #define home_pwd_buf     (S.home_pwd_buf    )
 183 #define matches          (S.matches         )
 184 #define num_matches      (S.num_matches     )
 185 #define delptr           (S.delptr          )
 186 #define newdelflag       (S.newdelflag      )
 187 #define delbuf           (S.delbuf          )
 188
 189 #define INIT_S() do { \
 190         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 191         barrier(); \
 192         cmdedit_termw = 80; \
 193         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 194         IF_FEATURE_EDITING_VI(delptr = delbuf;) \
 195 } while (0)
 196
 197 static void deinit_S(void)
 198 {
 199 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 200         /* This one is allocated only if FANCY_PROMPT is on
 201          * (otherwise it points to verbatim prompt (NOT malloced)) */
 202         free((char*)cmdedit_prompt);
 203 #endif
 204 #if ENABLE_USERNAME_OR_HOMEDIR
 205         free(user_buf);
 206         if (home_pwd_buf != null_str)
 207                 free(home_pwd_buf);
 208 #endif
 209         free(lineedit_ptr_to_statics);
 210 }
 211 #define DEINIT_S() deinit_S()
 212
 213
 214 #if ENABLE_UNICODE_SUPPORT
 215 static size_t load_string(const char *src)
 216 {
 217         if (unicode_status == UNICODE_ON) {
 218                 ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
 219                 if (len < 0)
 220                         len = 0;
 221                 command_ps[len] = BB_NUL;
 222                 return len;
 223         } else {
 224                 unsigned i = 0;
 225                 while (src[i] && i < S.maxsize - 1) {
 226                         command_ps[i] = src[i];
 227                         i++;
 228                 }
 229                 command_ps[i] = BB_NUL;
 230                 return i;
 231         }
 232 }
 233 static unsigned save_string(char *dst, unsigned maxsize)
 234 {
 235         if (unicode_status == UNICODE_ON) {
 236 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 237                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 238                 if (len < 0)
 239                         len = 0;
 240                 dst[len] = '\0';
 241                 return len;
 242 # else
 243                 unsigned dstpos = 0;
 244                 unsigned srcpos = 0;
 245
 246                 maxsize--;
 247                 while (dstpos < maxsize) {
 248                         wchar_t wc;
 249                         int n = srcpos;
 250
 251                         /* Convert up to 1st invalid byte (or up to end) */
 252                         while ((wc = command_ps[srcpos]) != BB_NUL
 253                             && !unicode_is_raw_byte(wc)
 254                         ) {
 255                                 srcpos++;
 256                         }
 257                         command_ps[srcpos] = BB_NUL;
 258                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 259                         if (n < 0) /* should not happen */
 260                                 break;
 261                         dstpos += n;
 262                         if (wc == BB_NUL) /* usually is */
 263                                 break;
 264
 265                         /* We do have invalid byte here! */
 266                         command_ps[srcpos] = wc; /* restore it */
 267                         srcpos++;
 268                         if (dstpos == maxsize)
 269                                 break;
 270                         dst[dstpos++] = (char) wc;
 271                 }
 272                 dst[dstpos] = '\0';
 273                 return dstpos;
 274 # endif
 275         } else {
 276                 unsigned i = 0;
 277                 while ((dst[i] = command_ps[i]) != 0)
 278                         i++;
 279                 return i;
 280         }
 281 }
 282 /* I thought just fputwc(c, stdout) would work. But no... */
 283 static void BB_PUTCHAR(wchar_t c)
 284 {
 285         if (unicode_status == UNICODE_ON) {
 286                 char buf[MB_CUR_MAX + 1];
 287                 mbstate_t mbst = { 0 };
 288                 ssize_t len = wcrtomb(buf, c, &mbst);
 289                 if (len > 0) {
 290                         buf[len] = '\0';
 291                         fputs(buf, stdout);
 292                 }
 293         } else {
 294                 /* In this case, c is always one byte */
 295                 putchar(c);
 296         }
 297 }
 298 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 299 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 300 # else
 301 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 302 #  define adjust_width_and_validate_wc(width_adj, wc) \
 303         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 304 # endif
 305 {
 306         int w = 1;
 307
 308         if (unicode_status == UNICODE_ON) {
 309                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 310                         /* note: also true for unicode_is_raw_byte(wc) */
 311                         goto subst;
 312                 }
 313                 w = wcwidth(wc);
 314                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 315                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 316                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 317                 ) {
 318  subst:
 319                         w = 1;
 320                         wc = CONFIG_SUBST_WCHAR;
 321                 }
 322         }
 323
 324 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 325         *width_adj += w;
 326 #endif
 327         return wc;
 328 }
 329 #else /* !UNICODE */
 330 static size_t load_string(const char *src)
 331 {
 332         safe_strncpy(command_ps, src, S.maxsize);
 333         return strlen(command_ps);
 334 }
 335 # if ENABLE_FEATURE_TAB_COMPLETION
 336 static void save_string(char *dst, unsigned maxsize)
 337 {
 338         safe_strncpy(dst, command_ps, maxsize);
 339 }
 340 # endif
 341 # define BB_PUTCHAR(c) bb_putchar(c)
 342 /* Should never be called: */
 343 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 344 #endif
 345
 346
 347 /* Put 'command_ps[cursor]', cursor++.
 348  * Advance cursor on screen. If we reached right margin, scroll text up
 349  * and remove terminal margin effect by printing 'next_char' */
 350 #define HACK_FOR_WRONG_WIDTH 1
 351 static void put_cur_glyph_and_inc_cursor(void)
 352 {
 353         CHAR_T c = command_ps[cursor];
 354         unsigned width = 0;
 355         int ofs_to_right;
 356
 357         if (c == BB_NUL) {
 358                 /* erase character after end of input string */
 359                 c = ' ';
 360         } else {
 361                 /* advance cursor only if we aren't at the end yet */
 362                 cursor++;
 363                 if (unicode_status == UNICODE_ON) {
 364                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 365                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 366                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 367                 } else {
 368                         cmdedit_x++;
 369                 }
 370         }
 371
 372         ofs_to_right = cmdedit_x - cmdedit_termw;
 373         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 374                 /* c fits on this line */
 375                 BB_PUTCHAR(c);
 376         }
 377
 378         if (ofs_to_right >= 0) {
 379                 /* we go to the next line */
 380 #if HACK_FOR_WRONG_WIDTH
 381                 /* This works better if our idea of term width is wrong
 382                  * and it is actually wider (often happens on serial lines).
 383                  * Printing CR,LF *forces* cursor to next line.
 384                  * OTOH if terminal width is correct AND terminal does NOT
 385                  * have automargin (IOW: it is moving cursor to next line
 386                  * by itself (which is wrong for VT-10x terminals)),
 387                  * this will break things: there will be one extra empty line */
 388                 puts("\r"); /* + implicit '\n' */
 389 #else
 390                 /* VT-10x terminals don't wrap cursor to next line when last char
 391                  * on the line is printed - cursor stays "over" this char.
 392                  * Need to print _next_ char too (first one to appear on next line)
 393                  * to make cursor move down to next line.
 394                  */
 395                 /* Works ok only if cmdedit_termw is correct. */
 396                 c = command_ps[cursor];
 397                 if (c == BB_NUL)
 398                         c = ' ';
 399                 BB_PUTCHAR(c);
 400                 bb_putchar('\b');
 401 #endif
 402                 cmdedit_y++;
 403                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 404                         width = 0;
 405                 } else { /* ofs_to_right > 0 */
 406                         /* wide char c didn't fit on prev line */
 407                         BB_PUTCHAR(c);
 408                 }
 409                 cmdedit_x = width;
 410         }
 411 }
 412
 413 /* Move to end of line (by printing all chars till the end) */
 414 static void put_till_end_and_adv_cursor(void)
 415 {
 416         while (cursor < command_len)
 417                 put_cur_glyph_and_inc_cursor();
 418 }
 419
 420 /* Go to the next line */
 421 static void goto_new_line(void)
 422 {
 423         put_till_end_and_adv_cursor();
 424         if (cmdedit_x != 0)
 425                 bb_putchar('\n');
 426 }
 427
 428 static void beep(void)
 429 {
 430         bb_putchar('\007');
 431 }
 432
 433 static void put_prompt(void)
 434 {
 435         unsigned w;
 436
 437         fputs(cmdedit_prompt, stdout);
 438         fflush_all();
 439         cursor = 0;
 440         w = cmdedit_termw; /* read volatile var once */
 441         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 442         cmdedit_x = cmdedit_prmt_len % w;
 443 }
 444
 445 /* Move back one character */
 446 /* (optimized for slow terminals) */
 447 static void input_backward(unsigned num)
 448 {
 449         if (num > cursor)
 450                 num = cursor;
 451         if (num == 0)
 452                 return;
 453         cursor -= num;
 454
 455         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 456          && unicode_status == UNICODE_ON
 457         ) {
 458                 /* correct NUM to be equal to _screen_ width */
 459                 int n = num;
 460                 num = 0;
 461                 while (--n >= 0)
 462                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 463                 if (num == 0)
 464                         return;
 465         }
 466
 467         if (cmdedit_x >= num) {
 468                 cmdedit_x -= num;
 469                 if (num <= 4) {
 470                         /* This is longer by 5 bytes on x86.
 471                          * Also gets miscompiled for ARM users
 472                          * (busybox.net/bugs/view.php?id=2274).
 473                          * printf(("\b\b\b\b" + 4) - num);
 474                          * return;
 475                          */
 476                         do {
 477                                 bb_putchar('\b');
 478                         } while (--num);
 479                         return;
 480                 }
 481                 printf(ESC"[%uD", num);
 482                 return;
 483         }
 484
 485         /* Need to go one or more lines up */
 486         if (ENABLE_UNICODE_WIDE_WCHARS) {
 487                 /* With wide chars, it is hard to "backtrack"
 488                  * and reliably figure out where to put cursor.
 489                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 490                  * |prompt: <><> |
 491                  * |<><><><><><> |
 492                  * |_            |
 493                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 494                  * We need to go up one line, and then - how do we know that
 495                  * we need to go *10* positions to the right? Because
 496                  * |prompt: <>#<>|
 497                  * |<><><>#<><><>|
 498                  * |_            |
 499                  * in this situation we need to go *11* positions to the right.
 500                  *
 501                  * A simpler thing to do is to redraw everything from the start
 502                  * up to new cursor position (which is already known):
 503                  */
 504                 unsigned sv_cursor;
 505                 /* go to 1st column; go up to first line */
 506                 printf("\r" ESC"[%uA", cmdedit_y);
 507                 cmdedit_y = 0;
 508                 sv_cursor = cursor;
 509                 put_prompt(); /* sets cursor to 0 */
 510                 while (cursor < sv_cursor)
 511                         put_cur_glyph_and_inc_cursor();
 512         } else {
 513                 int lines_up;
 514                 unsigned width;
 515                 /* num = chars to go back from the beginning of current line: */
 516                 num -= cmdedit_x;
 517                 width = cmdedit_termw; /* read volatile var once */
 518                 /* num=1...w: one line up, w+1...2w: two, etc: */
 519                 lines_up = 1 + (num - 1) / width;
 520                 cmdedit_x = (width * cmdedit_y - num) % width;
 521                 cmdedit_y -= lines_up;
 522                 /* go to 1st column; go up */
 523                 printf("\r" ESC"[%uA", lines_up);
 524                 /* go to correct column.
 525                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 526                  * need to *make sure* we skip it if cmdedit_x == 0 */
 527                 if (cmdedit_x)
 528                         printf(ESC"[%uC", cmdedit_x);
 529         }
 530 }
 531
 532 /* draw prompt, editor line, and clear tail */
 533 static void redraw(int y, int back_cursor)
 534 {
 535         if (y > 0) /* up y lines */
 536                 printf(ESC"[%uA", y);
 537         bb_putchar('\r');
 538         put_prompt();
 539         put_till_end_and_adv_cursor();
 540         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 541         input_backward(back_cursor);
 542 }
 543
 544 /* Delete the char in front of the cursor, optionally saving it
 545  * for later putback */
 546 #if !ENABLE_FEATURE_EDITING_VI
 547 static void input_delete(void)
 548 #define input_delete(save) input_delete()
 549 #else
 550 static void input_delete(int save)
 551 #endif
 552 {
 553         int j = cursor;
 554
 555         if (j == (int)command_len)
 556                 return;
 557
 558 #if ENABLE_FEATURE_EDITING_VI
 559         if (save) {
 560                 if (newdelflag) {
 561                         delptr = delbuf;
 562                         newdelflag = 0;
 563                 }
 564                 if ((delptr - delbuf) < DELBUFSIZ)
 565                         *delptr++ = command_ps[j];
 566         }
 567 #endif
 568
 569         memmove(command_ps + j, command_ps + j + 1,
 570                         /* (command_len + 1 [because of NUL]) - (j + 1)
 571                          * simplified into (command_len - j) */
 572                         (command_len - j) * sizeof(command_ps[0]));
 573         command_len--;
 574         put_till_end_and_adv_cursor();
 575         /* Last char is still visible, erase it (and more) */
 576         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 577         input_backward(cursor - j);     /* back to old pos cursor */
 578 }
 579
 580 #if ENABLE_FEATURE_EDITING_VI
 581 static void put(void)
 582 {
 583         int ocursor;
 584         int j = delptr - delbuf;
 585
 586         if (j == 0)
 587                 return;
 588         ocursor = cursor;
 589         /* open hole and then fill it */
 590         memmove(command_ps + cursor + j, command_ps + cursor,
 591                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 592         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 593         command_len += j;
 594         put_till_end_and_adv_cursor();
 595         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 596 }
 597 #endif
 598
 599 /* Delete the char in back of the cursor */
 600 static void input_backspace(void)
 601 {
 602         if (cursor > 0) {
 603                 input_backward(1);
 604                 input_delete(0);
 605         }
 606 }
 607
 608 /* Move forward one character */
 609 static void input_forward(void)
 610 {
 611         if (cursor < command_len)
 612                 put_cur_glyph_and_inc_cursor();
 613 }
 614
 615 #if ENABLE_FEATURE_TAB_COMPLETION
 616
 617 //FIXME:
 618 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 619 //matches the file named "foo bar", which is untrue.
 620 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 621 //not "foo bar <cursor>...
 622
 623 static void free_tab_completion_data(void)
 624 {
 625         if (matches) {
 626                 while (num_matches)
 627                         free(matches[--num_matches]);
 628                 free(matches);
 629                 matches = NULL;
 630         }
 631 }
 632
 633 static void add_match(char *matched)
 634 {
 635         matches = xrealloc_vector(matches, 4, num_matches);
 636         matches[num_matches] = matched;
 637         num_matches++;
 638 }
 639
 640 # if ENABLE_FEATURE_USERNAME_COMPLETION
 641 /* Replace "~user/..." with "/homedir/...".
 642  * The parameter is malloced, free it or return it
 643  * unchanged if no user is matched.
 644  */
 645 static char *username_path_completion(char *ud)
 646 {
 647         struct passwd *entry;
 648         char *tilde_name = ud;
 649         char *home = NULL;
 650
 651         ud++; /* skip ~ */
 652         if (*ud == '/') {       /* "~/..." */
 653                 home = home_pwd_buf;
 654         } else {
 655                 /* "~user/..." */
 656                 ud = strchr(ud, '/');
 657                 *ud = '\0';           /* "~user" */
 658                 entry = getpwnam(tilde_name + 1);
 659                 *ud = '/';            /* restore "~user/..." */
 660                 if (entry)
 661                         home = entry->pw_dir;
 662         }
 663         if (home) {
 664                 ud = concat_path_file(home, ud);
 665                 free(tilde_name);
 666                 tilde_name = ud;
 667         }
 668         return tilde_name;
 669 }
 670
 671 /* ~use<tab> - find all users with this prefix.
 672  * Return the length of the prefix used for matching.
 673  */
 674 static NOINLINE unsigned complete_username(const char *ud)
 675 {
 676         struct passwd *pw;
 677         unsigned userlen;
 678
 679         ud++; /* skip ~ */
 680         userlen = strlen(ud);
 681
 682         setpwent();
 683         while ((pw = getpwent()) != NULL) {
 684                 /* Null usernames should result in all users as possible completions. */
 685                 if (/* !ud[0] || */ is_prefixed_with(pw->pw_name, ud)) {
 686                         add_match(xasprintf("~%s/", pw->pw_name));
 687                 }
 688         }
 689         endpwent(); /* don't keep password file open */
 690
 691         return 1 + userlen;
 692 }
 693 # endif  /* FEATURE_USERNAME_COMPLETION */
 694
 695 enum {
 696         FIND_EXE_ONLY = 0,
 697         FIND_DIR_ONLY = 1,
 698         FIND_FILE_ONLY = 2,
 699 };
 700
 701 static int path_parse(char ***p)
 702 {
 703         int npth;
 704         const char *pth;
 705         char *tmp;
 706         char **res;
 707
 708         if (state->flags & WITH_PATH_LOOKUP)
 709                 pth = state->path_lookup;
 710         else
 711                 pth = getenv("PATH");
 712
 713         /* PATH="" or PATH=":"? */
 714         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 715                 return 1;
 716
 717         tmp = (char*)pth;
 718         npth = 1; /* path component count */
 719         while (1) {
 720                 tmp = strchr(tmp, ':');
 721                 if (!tmp)
 722                         break;
 723                 tmp++;
 724                 if (*tmp == '\0')
 725                         break;  /* :<empty> */
 726                 npth++;
 727         }
 728
 729         *p = res = xmalloc(npth * sizeof(res[0]));
 730         res[0] = tmp = xstrdup(pth);
 731         npth = 1;
 732         while (1) {
 733                 tmp = strchr(tmp, ':');
 734                 if (!tmp)
 735                         break;
 736                 *tmp++ = '\0'; /* ':' -> '\0' */
 737                 if (*tmp == '\0')
 738                         break; /* :<empty> */
 739                 res[npth++] = tmp;
 740         }
 741         return npth;
 742 }
 743
 744 /* Complete command, directory or file name.
 745  * Return the length of the prefix used for matching.
 746  */
 747 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 748 {
 749         char *path1[1];
 750         char **paths = path1;
 751         int npaths;
 752         int i;
 753         unsigned pf_len;
 754         const char *pfind;
 755         char *dirbuf = NULL;
 756
 757         npaths = 1;
 758         path1[0] = (char*)".";
 759
 760         pfind = strrchr(command, '/');
 761         if (!pfind) {
 762                 if (type == FIND_EXE_ONLY)
 763                         npaths = path_parse(&paths);
 764                 pfind = command;
 765         } else {
 766                 /* point to 'l' in "..../last_component" */
 767                 pfind++;
 768                 /* dirbuf = ".../.../.../" */
 769                 dirbuf = xstrndup(command, pfind - command);
 770 # if ENABLE_FEATURE_USERNAME_COMPLETION
 771                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 772                         dirbuf = username_path_completion(dirbuf);
 773 # endif
 774                 path1[0] = dirbuf;
 775         }
 776         pf_len = strlen(pfind);
 777
 778 #if ENABLE_FEATURE_SH_STANDALONE && NUM_APPLETS != 1
 779         if (type == FIND_EXE_ONLY) {
 780                 const char *p = applet_names;
 781
 782                 while (*p) {
 783                         if (strncmp(pfind, p, pf_len) == 0)
 784                                 add_match(xstrdup(p));
 785                         while (*p++ != '\0')
 786                                 continue;
 787                 }
 788         }
 789 #endif
 790
 791         for (i = 0; i < npaths; i++) {
 792                 DIR *dir;
 793                 struct dirent *next;
 794                 struct stat st;
 795                 char *found;
 796
 797                 dir = opendir(paths[i]);
 798                 if (!dir)
 799                         continue; /* don't print an error */
 800
 801                 while ((next = readdir(dir)) != NULL) {
 802                         unsigned len;
 803                         const char *name_found = next->d_name;
 804
 805                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 806                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 807                                 continue;
 808                         /* match? */
 809                         if (!is_prefixed_with(name_found, pfind))
 810                                 continue; /* no */
 811
 812                         found = concat_path_file(paths[i], name_found);
 813                         /* NB: stat() first so that we see is it a directory;
 814                          * but if that fails, use lstat() so that
 815                          * we still match dangling links */
 816                         if (stat(found, &st) && lstat(found, &st))
 817                                 goto cont; /* hmm, remove in progress? */
 818
 819                         /* Save only name */
 820                         len = strlen(name_found);
 821                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 822                         strcpy(found, name_found);
 823
 824                         if (S_ISDIR(st.st_mode)) {
 825                                 /* name is a directory, add slash */
 826                                 found[len] = '/';
 827                                 found[len + 1] = '\0';
 828                         } else {
 829                                 /* skip files if looking for dirs only (example: cd) */
 830                                 if (type == FIND_DIR_ONLY)
 831                                         goto cont;
 832                         }
 833                         /* add it to the list */
 834                         add_match(found);
 835                         continue;
 836  cont:
 837                         free(found);
 838                 }
 839                 closedir(dir);
 840         } /* for every path */
 841
 842         if (paths != path1) {
 843                 free(paths[0]); /* allocated memory is only in first member */
 844                 free(paths);
 845         }
 846         free(dirbuf);
 847
 848         return pf_len;
 849 }
 850
 851 /* build_match_prefix:
 852  * On entry, match_buf contains everything up to cursor at the moment <tab>
 853  * was pressed. This function looks at it, figures out what part of it
 854  * constitutes the command/file/directory prefix to use for completion,
 855  * and rewrites match_buf to contain only that part.
 856  */
 857 #define dbg_bmp 0
 858 /* Helpers: */
 859 /* QUOT is used on elements of int_buf[], which are bytes,
 860  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 861  */
 862 #define QUOT (UCHAR_MAX+1)
 863 static void remove_chunk(int16_t *int_buf, int beg, int end)
 864 {
 865         /* beg must be <= end */
 866         if (beg == end)
 867                 return;
 868
 869         while ((int_buf[beg] = int_buf[end]) != 0)
 870                 beg++, end++;
 871
 872         if (dbg_bmp) {
 873                 int i;
 874                 for (i = 0; int_buf[i]; i++)
 875                         bb_putchar((unsigned char)int_buf[i]);
 876                 bb_putchar('\n');
 877         }
 878 }
 879 /* Caller ensures that match_buf points to a malloced buffer
 880  * big enough to hold strlen(match_buf)*2 + 2
 881  */
 882 static NOINLINE int build_match_prefix(char *match_buf)
 883 {
 884         int i, j;
 885         int command_mode;
 886         int16_t *int_buf = (int16_t*)match_buf;
 887
 888         if (dbg_bmp) printf("\n%s\n", match_buf);
 889
 890         /* Copy in reverse order, since they overlap */
 891         i = strlen(match_buf);
 892         do {
 893                 int_buf[i] = (unsigned char)match_buf[i];
 894                 i--;
 895         } while (i >= 0);
 896
 897         /* Mark every \c as "quoted c" */
 898         for (i = 0; int_buf[i]; i++) {
 899                 if (int_buf[i] == '\\') {
 900                         remove_chunk(int_buf, i, i + 1);
 901                         int_buf[i] |= QUOT;
 902                 }
 903         }
 904         /* Quote-mark "chars" and 'chars', drop delimiters */
 905         {
 906                 int in_quote = 0;
 907                 i = 0;
 908                 while (int_buf[i]) {
 909                         int cur = int_buf[i];
 910                         if (!cur)
 911                                 break;
 912                         if (cur == '\'' || cur == '"') {
 913                                 if (!in_quote || (cur == in_quote)) {
 914                                         in_quote ^= cur;
 915                                         remove_chunk(int_buf, i, i + 1);
 916                                         continue;
 917                                 }
 918                         }
 919                         if (in_quote)
 920                                 int_buf[i] = cur | QUOT;
 921                         i++;
 922                 }
 923         }
 924
 925         /* Remove everything up to command delimiters:
 926          * ';' ';;' '&' '|' '&&' '||',
 927          * but careful with '>&' '<&' '>|'
 928          */
 929         for (i = 0; int_buf[i]; i++) {
 930                 int cur = int_buf[i];
 931                 if (cur == ';' || cur == '&' || cur == '|') {
 932                         int prev = i ? int_buf[i - 1] : 0;
 933                         if (cur == '&' && (prev == '>' || prev == '<')) {
 934                                 continue;
 935                         } else if (cur == '|' && prev == '>') {
 936                                 continue;
 937                         }
 938                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 939                         i = -1;  /* back to square 1 */
 940                 }
 941         }
 942         /* Remove all `cmd` */
 943         for (i = 0; int_buf[i]; i++) {
 944                 if (int_buf[i] == '`') {
 945                         for (j = i + 1; int_buf[j]; j++) {
 946                                 if (int_buf[j] == '`') {
 947                                         /* `cmd` should count as a word:
 948                                          * `cmd` c<tab> should search for files c*,
 949                                          * not commands c*. Therefore we don't drop
 950                                          * `cmd` entirely, we replace it with single `.
 951                                          */
 952                                         remove_chunk(int_buf, i, j);
 953                                         goto next;
 954                                 }
 955                         }
 956                         /* No closing ` - command mode, remove all up to ` */
 957                         remove_chunk(int_buf, 0, i + 1);
 958                         break;
 959  next: ;
 960                 }
 961         }
 962
 963         /* Remove "cmd (" and "cmd {"
 964          * Example: "if { c<tab>"
 965          * In this example, c should be matched as command pfx.
 966          */
 967         for (i = 0; int_buf[i]; i++) {
 968                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 969                         remove_chunk(int_buf, 0, i + 1);
 970                         i = -1;  /* back to square 1 */
 971                 }
 972         }
 973
 974         /* Remove leading unquoted spaces */
 975         for (i = 0; int_buf[i]; i++)
 976                 if (int_buf[i] != ' ')
 977                         break;
 978         remove_chunk(int_buf, 0, i);
 979
 980         /* Determine completion mode */
 981         command_mode = FIND_EXE_ONLY;
 982         for (i = 0; int_buf[i]; i++) {
 983                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 984                         if (int_buf[i] == ' '
 985                          && command_mode == FIND_EXE_ONLY
 986                          && (char)int_buf[0] == 'c'
 987                          && (char)int_buf[1] == 'd'
 988                          && i == 2 /* -> int_buf[2] == ' ' */
 989                         ) {
 990                                 command_mode = FIND_DIR_ONLY;
 991                         } else {
 992                                 command_mode = FIND_FILE_ONLY;
 993                                 break;
 994                         }
 995                 }
 996         }
 997         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 998
 999         /* Remove everything except last word */
1000         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
1001                 continue;
1002         for (--i; i >= 0; i--) {
1003                 int cur = int_buf[i];
1004                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
1005                         remove_chunk(int_buf, 0, i + 1);
1006                         break;
1007                 }
1008         }
1009
1010         /* Convert back to string of _chars_ */
1011         i = 0;
1012         while ((match_buf[i] = int_buf[i]) != '\0')
1013                 i++;
1014
1015         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
1016
1017         return command_mode;
1018 }
1019
1020 /*
1021  * Display by column (original idea from ls applet,
1022  * very optimized by me [Vladimir] :)
1023  */
1024 static void showfiles(void)
1025 {
1026         int ncols, row;
1027         int column_width = 0;
1028         int nfiles = num_matches;
1029         int nrows = nfiles;
1030         int l;
1031
1032         /* find the longest file name - use that as the column width */
1033         for (row = 0; row < nrows; row++) {
1034                 l = unicode_strwidth(matches[row]);
1035                 if (column_width < l)
1036                         column_width = l;
1037         }
1038         column_width += 2;              /* min space for columns */
1039         ncols = cmdedit_termw / column_width;
1040
1041         if (ncols > 1) {
1042                 nrows /= ncols;
1043                 if (nfiles % ncols)
1044                         nrows++;        /* round up fractionals */
1045         } else {
1046                 ncols = 1;
1047         }
1048         for (row = 0; row < nrows; row++) {
1049                 int n = row;
1050                 int nc;
1051
1052                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1053                         printf("%s%-*s", matches[n],
1054                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1055                         );
1056                 }
1057                 if (ENABLE_UNICODE_SUPPORT)
1058                         puts(printable_string(NULL, matches[n]));
1059                 else
1060                         puts(matches[n]);
1061         }
1062 }
1063
1064 static const char *is_special_char(char c)
1065 {
1066         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1067 }
1068
1069 static char *quote_special_chars(char *found)
1070 {
1071         int l = 0;
1072         char *s = xzalloc((strlen(found) + 1) * 2);
1073
1074         while (*found) {
1075                 if (is_special_char(*found))
1076                         s[l++] = '\\';
1077                 s[l++] = *found++;
1078         }
1079         /* s[l] = '\0'; - already is */
1080         return s;
1081 }
1082
1083 /* Do TAB completion */
1084 static NOINLINE void input_tab(smallint *lastWasTab)
1085 {
1086         char *chosen_match;
1087         char *match_buf;
1088         size_t len_found;
1089         /* Length of string used for matching */
1090         unsigned match_pfx_len = match_pfx_len;
1091         int find_type;
1092 # if ENABLE_UNICODE_SUPPORT
1093         /* cursor pos in command converted to multibyte form */
1094         int cursor_mb;
1095 # endif
1096         if (!(state->flags & TAB_COMPLETION))
1097                 return;
1098
1099         if (*lastWasTab) {
1100                 /* The last char was a TAB too.
1101                  * Print a list of all the available choices.
1102                  */
1103                 if (num_matches > 0) {
1104                         /* cursor will be changed by goto_new_line() */
1105                         int sav_cursor = cursor;
1106                         goto_new_line();
1107                         showfiles();
1108                         redraw(0, command_len - sav_cursor);
1109                 }
1110                 return;
1111         }
1112
1113         *lastWasTab = 1;
1114         chosen_match = NULL;
1115
1116         /* Make a local copy of the string up to the position of the cursor.
1117          * build_match_prefix will expand it into int16_t's, need to allocate
1118          * twice as much as the string_len+1.
1119          * (we then also (ab)use this extra space later - see (**))
1120          */
1121         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1122 # if !ENABLE_UNICODE_SUPPORT
1123         save_string(match_buf, cursor + 1); /* +1 for NUL */
1124 # else
1125         {
1126                 CHAR_T wc = command_ps[cursor];
1127                 command_ps[cursor] = BB_NUL;
1128                 save_string(match_buf, MAX_LINELEN);
1129                 command_ps[cursor] = wc;
1130                 cursor_mb = strlen(match_buf);
1131         }
1132 # endif
1133         find_type = build_match_prefix(match_buf);
1134
1135         /* Free up any memory already allocated */
1136         free_tab_completion_data();
1137
1138 # if ENABLE_FEATURE_USERNAME_COMPLETION
1139         /* If the word starts with ~ and there is no slash in the word,
1140          * then try completing this word as a username. */
1141         if (state->flags & USERNAME_COMPLETION)
1142                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1143                         match_pfx_len = complete_username(match_buf);
1144 # endif
1145         /* If complete_username() did not match,
1146          * try to match a command in $PATH, or a directory, or a file */
1147         if (!matches)
1148                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1149
1150         /* Account for backslashes which will be inserted
1151          * by quote_special_chars() later */
1152         {
1153                 const char *e = match_buf + strlen(match_buf);
1154                 const char *s = e - match_pfx_len;
1155                 while (s < e)
1156                         if (is_special_char(*s++))
1157                                 match_pfx_len++;
1158         }
1159
1160         /* Remove duplicates */
1161         if (matches) {
1162                 unsigned i, n = 0;
1163                 qsort_string_vector(matches, num_matches);
1164                 for (i = 0; i < num_matches - 1; ++i) {
1165                         //if (matches[i] && matches[i+1]) { /* paranoia */
1166                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1167                                         free(matches[i]);
1168                                         //matches[i] = NULL; /* paranoia */
1169                                 } else {
1170                                         matches[n++] = matches[i];
1171                                 }
1172                         //}
1173                 }
1174                 matches[n++] = matches[i];
1175                 num_matches = n;
1176         }
1177
1178         /* Did we find exactly one match? */
1179         if (num_matches != 1) { /* no */
1180                 char *cp;
1181                 beep();
1182                 if (!matches)
1183                         goto ret; /* no matches at all */
1184                 /* Find common prefix */
1185                 chosen_match = xstrdup(matches[0]);
1186                 for (cp = chosen_match; *cp; cp++) {
1187                         unsigned n;
1188                         for (n = 1; n < num_matches; n++) {
1189                                 if (matches[n][cp - chosen_match] != *cp) {
1190                                         goto stop;
1191                                 }
1192                         }
1193                 }
1194  stop:
1195                 if (cp == chosen_match) { /* have unique prefix? */
1196                         goto ret; /* no */
1197                 }
1198                 *cp = '\0';
1199                 cp = quote_special_chars(chosen_match);
1200                 free(chosen_match);
1201                 chosen_match = cp;
1202                 len_found = strlen(chosen_match);
1203         } else {                        /* exactly one match */
1204                 /* Next <tab> is not a double-tab */
1205                 *lastWasTab = 0;
1206
1207                 chosen_match = quote_special_chars(matches[0]);
1208                 len_found = strlen(chosen_match);
1209                 if (chosen_match[len_found-1] != '/') {
1210                         chosen_match[len_found] = ' ';
1211                         chosen_match[++len_found] = '\0';
1212                 }
1213         }
1214
1215 # if !ENABLE_UNICODE_SUPPORT
1216         /* Have space to place the match? */
1217         /* The result consists of three parts with these lengths: */
1218         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1219         /* it simplifies into: */
1220         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1221                 int pos;
1222                 /* save tail */
1223                 strcpy(match_buf, &command_ps[cursor]);
1224                 /* add match and tail */
1225                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1226                 command_len = strlen(command_ps);
1227                 /* new pos */
1228                 pos = cursor + len_found - match_pfx_len;
1229                 /* write out the matched command */
1230                 redraw(cmdedit_y, command_len - pos);
1231         }
1232 # else
1233         {
1234                 /* Use 2nd half of match_buf as scratch space - see (**) */
1235                 char *command = match_buf + MAX_LINELEN;
1236                 int len = save_string(command, MAX_LINELEN);
1237                 /* Have space to place the match? */
1238                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1239                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1240                         int pos;
1241                         /* save tail */
1242                         strcpy(match_buf, &command[cursor_mb]);
1243                         /* where do we want to have cursor after all? */
1244                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1245                         len = load_string(command);
1246                         /* add match and tail */
1247                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1248                         command_len = load_string(command);
1249                         /* write out the matched command */
1250                         /* paranoia: load_string can return 0 on conv error,
1251                          * prevent passing pos = (0 - 12) to redraw */
1252                         pos = command_len - len;
1253                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1254                 }
1255         }
1256 # endif
1257  ret:
1258         free(chosen_match);
1259         free(match_buf);
1260 }
1261
1262 #endif  /* FEATURE_TAB_COMPLETION */
1263
1264
1265 line_input_t* FAST_FUNC new_line_input_t(int flags)
1266 {
1267         line_input_t *n = xzalloc(sizeof(*n));
1268         n->flags = flags;
1269 #if MAX_HISTORY > 0
1270         n->max_history = MAX_HISTORY;
1271 #endif
1272         return n;
1273 }
1274
1275
1276 #if MAX_HISTORY > 0
1277
1278 unsigned FAST_FUNC size_from_HISTFILESIZE(const char *hp)
1279 {
1280         int size = MAX_HISTORY;
1281         if (hp) {
1282                 size = atoi(hp);
1283                 if (size <= 0)
1284                         return 1;
1285                 if (size > MAX_HISTORY)
1286                         return MAX_HISTORY;
1287         }
1288         return size;
1289 }
1290
1291 static void save_command_ps_at_cur_history(void)
1292 {
1293         if (command_ps[0] != BB_NUL) {
1294                 int cur = state->cur_history;
1295                 free(state->history[cur]);
1296
1297 # if ENABLE_UNICODE_SUPPORT
1298                 {
1299                         char tbuf[MAX_LINELEN];
1300                         save_string(tbuf, sizeof(tbuf));
1301                         state->history[cur] = xstrdup(tbuf);
1302                 }
1303 # else
1304                 state->history[cur] = xstrdup(command_ps);
1305 # endif
1306         }
1307 }
1308
1309 /* state->flags is already checked to be nonzero */
1310 static int get_previous_history(void)
1311 {
1312         if ((state->flags & DO_HISTORY) && state->cur_history) {
1313                 save_command_ps_at_cur_history();
1314                 state->cur_history--;
1315                 return 1;
1316         }
1317         beep();
1318         return 0;
1319 }
1320
1321 static int get_next_history(void)
1322 {
1323         if (state->flags & DO_HISTORY) {
1324                 if (state->cur_history < state->cnt_history) {
1325                         save_command_ps_at_cur_history(); /* save the current history line */
1326                         return ++state->cur_history;
1327                 }
1328         }
1329         beep();
1330         return 0;
1331 }
1332
1333 /* Lists command history. Used by shell 'history' builtins */
1334 void FAST_FUNC show_history(const line_input_t *st)
1335 {
1336         int i;
1337
1338         if (!st)
1339                 return;
1340         for (i = 0; i < st->cnt_history; i++)
1341                 printf("%4d %s\n", i, st->history[i]);
1342 }
1343
1344 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1345 /* We try to ensure that concurrent additions to the history
1346  * do not overwrite each other.
1347  * Otherwise shell users get unhappy.
1348  *
1349  * History file is trimmed lazily, when it grows several times longer
1350  * than configured MAX_HISTORY lines.
1351  */
1352
1353 static void free_line_input_t(line_input_t *n)
1354 {
1355         int i = n->cnt_history;
1356         while (i > 0)
1357                 free(n->history[--i]);
1358         free(n);
1359 }
1360
1361 /* state->flags is already checked to be nonzero */
1362 static void load_history(line_input_t *st_parm)
1363 {
1364         char *temp_h[MAX_HISTORY];
1365         char *line;
1366         FILE *fp;
1367         unsigned idx, i, line_len;
1368
1369         /* NB: do not trash old history if file can't be opened */
1370
1371         fp = fopen_for_read(st_parm->hist_file);
1372         if (fp) {
1373                 /* clean up old history */
1374                 for (idx = st_parm->cnt_history; idx > 0;) {
1375                         idx--;
1376                         free(st_parm->history[idx]);
1377                         st_parm->history[idx] = NULL;
1378                 }
1379
1380                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1381                 memset(temp_h, 0, sizeof(temp_h));
1382                 idx = 0;
1383                 st_parm->cnt_history_in_file = 0;
1384                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1385                         if (line[0] == '\0') {
1386                                 free(line);
1387                                 continue;
1388                         }
1389                         free(temp_h[idx]);
1390                         temp_h[idx] = line;
1391                         st_parm->cnt_history_in_file++;
1392                         idx++;
1393                         if (idx == st_parm->max_history)
1394                                 idx = 0;
1395                 }
1396                 fclose(fp);
1397
1398                 /* find first non-NULL temp_h[], if any */
1399                 if (st_parm->cnt_history_in_file) {
1400                         while (temp_h[idx] == NULL) {
1401                                 idx++;
1402                                 if (idx == st_parm->max_history)
1403                                         idx = 0;
1404                         }
1405                 }
1406
1407                 /* copy temp_h[] to st_parm->history[] */
1408                 for (i = 0; i < st_parm->max_history;) {
1409                         line = temp_h[idx];
1410                         if (!line)
1411                                 break;
1412                         idx++;
1413                         if (idx == st_parm->max_history)
1414                                 idx = 0;
1415                         line_len = strlen(line);
1416                         if (line_len >= MAX_LINELEN)
1417                                 line[MAX_LINELEN-1] = '\0';
1418                         st_parm->history[i++] = line;
1419                 }
1420                 st_parm->cnt_history = i;
1421                 if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
1422                         st_parm->cnt_history_in_file = i;
1423         }
1424 }
1425
1426 #  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1427 void save_history(line_input_t *st)
1428 {
1429         FILE *fp;
1430
1431         if (!st->hist_file)
1432                 return;
1433         if (st->cnt_history <= st->cnt_history_in_file)
1434                 return;
1435
1436         fp = fopen(st->hist_file, "a");
1437         if (fp) {
1438                 int i, fd;
1439                 char *new_name;
1440                 line_input_t *st_temp;
1441
1442                 for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
1443                         fprintf(fp, "%s\n", st->history[i]);
1444                 fclose(fp);
1445
1446                 /* we may have concurrently written entries from others.
1447                  * load them */
1448                 st_temp = new_line_input_t(st->flags);
1449                 st_temp->hist_file = st->hist_file;
1450                 st_temp->max_history = st->max_history;
1451                 load_history(st_temp);
1452
1453                 /* write out temp file and replace hist_file atomically */
1454                 new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
1455                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1456                 if (fd >= 0) {
1457                         fp = xfdopen_for_write(fd);
1458                         for (i = 0; i < st_temp->cnt_history; i++)
1459                                 fprintf(fp, "%s\n", st_temp->history[i]);
1460                         fclose(fp);
1461                         if (rename(new_name, st->hist_file) == 0)
1462                                 st->cnt_history_in_file = st_temp->cnt_history;
1463                 }
1464                 free(new_name);
1465                 free_line_input_t(st_temp);
1466         }
1467 }
1468 #  else
1469 static void save_history(char *str)
1470 {
1471         int fd;
1472         int len, len2;
1473
1474         if (!state->hist_file)
1475                 return;
1476
1477         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1478         if (fd < 0)
1479                 return;
1480         xlseek(fd, 0, SEEK_END); /* paranoia */
1481         len = strlen(str);
1482         str[len] = '\n'; /* we (try to) do atomic write */
1483         len2 = full_write(fd, str, len + 1);
1484         str[len] = '\0';
1485         close(fd);
1486         if (len2 != len + 1)
1487                 return; /* "wtf?" */
1488
1489         /* did we write so much that history file needs trimming? */
1490         state->cnt_history_in_file++;
1491         if (state->cnt_history_in_file > state->max_history * 4) {
1492                 char *new_name;
1493                 line_input_t *st_temp;
1494
1495                 /* we may have concurrently written entries from others.
1496                  * load them */
1497                 st_temp = new_line_input_t(state->flags);
1498                 st_temp->hist_file = state->hist_file;
1499                 st_temp->max_history = state->max_history;
1500                 load_history(st_temp);
1501
1502                 /* write out temp file and replace hist_file atomically */
1503                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1504                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1505                 if (fd >= 0) {
1506                         FILE *fp;
1507                         int i;
1508
1509                         fp = xfdopen_for_write(fd);
1510                         for (i = 0; i < st_temp->cnt_history; i++)
1511                                 fprintf(fp, "%s\n", st_temp->history[i]);
1512                         fclose(fp);
1513                         if (rename(new_name, state->hist_file) == 0)
1514                                 state->cnt_history_in_file = st_temp->cnt_history;
1515                 }
1516                 free(new_name);
1517                 free_line_input_t(st_temp);
1518         }
1519 }
1520 #  endif
1521 # else
1522 #  define load_history(a) ((void)0)
1523 #  define save_history(a) ((void)0)
1524 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1525
1526 static void remember_in_history(char *str)
1527 {
1528         int i;
1529
1530         if (!(state->flags & DO_HISTORY))
1531                 return;
1532         if (str[0] == '\0')
1533                 return;
1534         i = state->cnt_history;
1535         /* Don't save dupes */
1536         if (i && strcmp(state->history[i-1], str) == 0)
1537                 return;
1538
1539         free(state->history[state->max_history]); /* redundant, paranoia */
1540         state->history[state->max_history] = NULL; /* redundant, paranoia */
1541
1542         /* If history[] is full, remove the oldest command */
1543         /* we need to keep history[state->max_history] empty, hence >=, not > */
1544         if (i >= state->max_history) {
1545                 free(state->history[0]);
1546                 for (i = 0; i < state->max_history-1; i++)
1547                         state->history[i] = state->history[i+1];
1548                 /* i == state->max_history-1 */
1549 # if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1550                 if (state->cnt_history_in_file)
1551                         state->cnt_history_in_file--;
1552 # endif
1553         }
1554         /* i <= state->max_history-1 */
1555         state->history[i++] = xstrdup(str);
1556         /* i <= state->max_history */
1557         state->cur_history = i;
1558         state->cnt_history = i;
1559 # if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1560         save_history(str);
1561 # endif
1562 }
1563
1564 #else /* MAX_HISTORY == 0 */
1565 # define remember_in_history(a) ((void)0)
1566 #endif /* MAX_HISTORY */
1567
1568
1569 #if ENABLE_FEATURE_EDITING_VI
1570 /*
1571  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1572  */
1573 static void
1574 vi_Word_motion(int eat)
1575 {
1576         CHAR_T *command = command_ps;
1577
1578         while (cursor < command_len && !BB_isspace(command[cursor]))
1579                 input_forward();
1580         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1581                 input_forward();
1582 }
1583
1584 static void
1585 vi_word_motion(int eat)
1586 {
1587         CHAR_T *command = command_ps;
1588
1589         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1590                 while (cursor < command_len
1591                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1592                 ) {
1593                         input_forward();
1594                 }
1595         } else if (BB_ispunct(command[cursor])) {
1596                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1597                         input_forward();
1598         }
1599
1600         if (cursor < command_len)
1601                 input_forward();
1602
1603         if (eat) {
1604                 while (cursor < command_len && BB_isspace(command[cursor]))
1605                         input_forward();
1606         }
1607 }
1608
1609 static void
1610 vi_End_motion(void)
1611 {
1612         CHAR_T *command = command_ps;
1613
1614         input_forward();
1615         while (cursor < command_len && BB_isspace(command[cursor]))
1616                 input_forward();
1617         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1618                 input_forward();
1619 }
1620
1621 static void
1622 vi_end_motion(void)
1623 {
1624         CHAR_T *command = command_ps;
1625
1626         if (cursor >= command_len-1)
1627                 return;
1628         input_forward();
1629         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1630                 input_forward();
1631         if (cursor >= command_len-1)
1632                 return;
1633         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1634                 while (cursor < command_len-1
1635                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1636                 ) {
1637                         input_forward();
1638                 }
1639         } else if (BB_ispunct(command[cursor])) {
1640                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1641                         input_forward();
1642         }
1643 }
1644
1645 static void
1646 vi_Back_motion(void)
1647 {
1648         CHAR_T *command = command_ps;
1649
1650         while (cursor > 0 && BB_isspace(command[cursor-1]))
1651                 input_backward(1);
1652         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1653                 input_backward(1);
1654 }
1655
1656 static void
1657 vi_back_motion(void)
1658 {
1659         CHAR_T *command = command_ps;
1660
1661         if (cursor <= 0)
1662                 return;
1663         input_backward(1);
1664         while (cursor > 0 && BB_isspace(command[cursor]))
1665                 input_backward(1);
1666         if (cursor <= 0)
1667                 return;
1668         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1669                 while (cursor > 0
1670                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1671                 ) {
1672                         input_backward(1);
1673                 }
1674         } else if (BB_ispunct(command[cursor])) {
1675                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1676                         input_backward(1);
1677         }
1678 }
1679 #endif
1680
1681 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1682 static void ctrl_left(void)
1683 {
1684         CHAR_T *command = command_ps;
1685
1686         while (1) {
1687                 CHAR_T c;
1688
1689                 input_backward(1);
1690                 if (cursor == 0)
1691                         break;
1692                 c = command[cursor];
1693                 if (c != ' ' && !BB_ispunct(c)) {
1694                         /* we reached a "word" delimited by spaces/punct.
1695                          * go to its beginning */
1696                         while (1) {
1697                                 c = command[cursor - 1];
1698                                 if (c == ' ' || BB_ispunct(c))
1699                                         break;
1700                                 input_backward(1);
1701                                 if (cursor == 0)
1702                                         break;
1703                         }
1704                         break;
1705                 }
1706         }
1707 }
1708 static void ctrl_right(void)
1709 {
1710         CHAR_T *command = command_ps;
1711
1712         while (1) {
1713                 CHAR_T c;
1714
1715                 c = command[cursor];
1716                 if (c == BB_NUL)
1717                         break;
1718                 if (c != ' ' && !BB_ispunct(c)) {
1719                         /* we reached a "word" delimited by spaces/punct.
1720                          * go to its end + 1 */
1721                         while (1) {
1722                                 input_forward();
1723                                 c = command[cursor];
1724                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1725                                         break;
1726                         }
1727                         break;
1728                 }
1729                 input_forward();
1730         }
1731 }
1732
1733
1734 /*
1735  * read_line_input and its helpers
1736  */
1737
1738 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1739 static void ask_terminal(void)
1740 {
1741         /* Ask terminal where is the cursor now.
1742          * lineedit_read_key handles response and corrects
1743          * our idea of current cursor position.
1744          * Testcase: run "echo -n long_line_long_line_long_line",
1745          * then type in a long, wrapping command and try to
1746          * delete it using backspace key.
1747          * Note: we print it _after_ prompt, because
1748          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1749          */
1750         /* Problem: if there is buffered input on stdin,
1751          * the response will be delivered later,
1752          * possibly to an unsuspecting application.
1753          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1754          * Result:
1755          * ~/srcdevel/bbox/fix/busybox.t4 #
1756          * ~/srcdevel/bbox/fix/busybox.t4 #
1757          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1758          * ~/srcdevel/bbox/fix/busybox.t4 #
1759          *
1760          * Checking for input with poll only makes the race narrower,
1761          * I still can trigger it. Strace:
1762          *
1763          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1764          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1765          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1766          * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
1767          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1768          */
1769         struct pollfd pfd;
1770
1771         pfd.fd = STDIN_FILENO;
1772         pfd.events = POLLIN;
1773         if (safe_poll(&pfd, 1, 0) == 0) {
1774                 S.sent_ESC_br6n = 1;
1775                 fputs(ESC"[6n", stdout);
1776                 fflush_all(); /* make terminal see it ASAP! */
1777         }
1778 }
1779 #else
1780 #define ask_terminal() ((void)0)
1781 #endif
1782
1783 /* Called just once at read_line_input() init time */
1784 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1785 static void parse_and_put_prompt(const char *prmt_ptr)
1786 {
1787         const char *p;
1788         cmdedit_prompt = prmt_ptr;
1789         p = strrchr(prmt_ptr, '\n');
1790         cmdedit_prmt_len = unicode_strwidth(p ? p+1 : prmt_ptr);
1791         put_prompt();
1792 }
1793 #else
1794 static void parse_and_put_prompt(const char *prmt_ptr)
1795 {
1796         int prmt_size = 0;
1797         char *prmt_mem_ptr = xzalloc(1);
1798 # if ENABLE_USERNAME_OR_HOMEDIR
1799         char *cwd_buf = NULL;
1800 # endif
1801         char flg_not_length = '[';
1802         char cbuf[2];
1803
1804         /*cmdedit_prmt_len = 0; - already is */
1805
1806         cbuf[1] = '\0'; /* never changes */
1807
1808         while (*prmt_ptr) {
1809                 char timebuf[sizeof("HH:MM:SS")];
1810                 char *free_me = NULL;
1811                 char *pbuf;
1812                 char c;
1813
1814                 pbuf = cbuf;
1815                 c = *prmt_ptr++;
1816                 if (c == '\\') {
1817                         const char *cp;
1818                         int l;
1819 /*
1820  * Supported via bb_process_escape_sequence:
1821  * \a   ASCII bell character (07)
1822  * \e   ASCII escape character (033)
1823  * \n   newline
1824  * \r   carriage return
1825  * \\   backslash
1826  * \nnn char with octal code nnn
1827  * Supported:
1828  * \$   if the effective UID is 0, a #, otherwise a $
1829  * \w   current working directory, with $HOME abbreviated with a tilde
1830  *      Note: we do not support $PROMPT_DIRTRIM=n feature
1831  * \W   basename of the current working directory, with $HOME abbreviated with a tilde
1832  * \h   hostname up to the first '.'
1833  * \H   hostname
1834  * \u   username
1835  * \[   begin a sequence of non-printing characters
1836  * \]   end a sequence of non-printing characters
1837  * \T   current time in 12-hour HH:MM:SS format
1838  * \@   current time in 12-hour am/pm format
1839  * \A   current time in 24-hour HH:MM format
1840  * \t   current time in 24-hour HH:MM:SS format
1841  *      (all of the above work as \A)
1842  * Not supported:
1843  * \!   history number of this command
1844  * \#   command number of this command
1845  * \j   number of jobs currently managed by the shell
1846  * \l   basename of the shell's terminal device name
1847  * \s   name of the shell, the basename of $0 (the portion following the final slash)
1848  * \V   release of bash, version + patch level (e.g., 2.00.0)
1849  * \d   date in "Weekday Month Date" format (e.g., "Tue May 26")
1850  * \D{format}
1851  *      format is passed to strftime(3).
1852  *      An empty format results in a locale-specific time representation.
1853  *      The braces are required.
1854  * Mishandled by bb_process_escape_sequence:
1855  * \v   version of bash (e.g., 2.00)
1856  */
1857                         cp = prmt_ptr;
1858                         c = *cp;
1859                         if (c != 't') /* don't treat \t as tab */
1860                                 c = bb_process_escape_sequence(&prmt_ptr);
1861                         if (prmt_ptr == cp) {
1862                                 if (*cp == '\0')
1863                                         break;
1864                                 c = *prmt_ptr++;
1865
1866                                 switch (c) {
1867 # if ENABLE_USERNAME_OR_HOMEDIR
1868                                 case 'u':
1869                                         pbuf = user_buf ? user_buf : (char*)"";
1870                                         break;
1871 # endif
1872                                 case 'H':
1873                                 case 'h':
1874                                         pbuf = free_me = safe_gethostname();
1875                                         if (c == 'h')
1876                                                 strchrnul(pbuf, '.')[0] = '\0';
1877                                         break;
1878                                 case '$':
1879                                         c = (geteuid() == 0 ? '#' : '$');
1880                                         break;
1881                                 case 'T': /* 12-hour HH:MM:SS format */
1882                                 case '@': /* 12-hour am/pm format */
1883                                 case 'A': /* 24-hour HH:MM format */
1884                                 case 't': /* 24-hour HH:MM:SS format */
1885                                         /* We show all of them as 24-hour HH:MM */
1886                                         strftime_HHMMSS(timebuf, sizeof(timebuf), NULL)[-3] = '\0';
1887                                         pbuf = timebuf;
1888                                         break;
1889 # if ENABLE_USERNAME_OR_HOMEDIR
1890                                 case 'w': /* current dir */
1891                                 case 'W': /* basename of cur dir */
1892                                         if (!cwd_buf) {
1893                                                 cwd_buf = xrealloc_getcwd_or_warn(NULL);
1894                                                 if (!cwd_buf)
1895                                                         cwd_buf = (char *)bb_msg_unknown;
1896                                                 else if (home_pwd_buf[0]) {
1897                                                         char *after_home_user;
1898
1899                                                         /* /home/user[/something] -> ~[/something] */
1900                                                         after_home_user = is_prefixed_with(cwd_buf, home_pwd_buf);
1901                                                         if (after_home_user
1902                                                          && (*after_home_user == '/' || *after_home_user == '\0')
1903                                                         ) {
1904                                                                 cwd_buf[0] = '~';
1905                                                                 overlapping_strcpy(cwd_buf + 1, after_home_user);
1906                                                         }
1907                                                 }
1908                                         }
1909                                         pbuf = cwd_buf;
1910                                         if (c == 'w')
1911                                                 break;
1912                                         cp = strrchr(pbuf, '/');
1913                                         if (cp)
1914                                                 pbuf = (char*)cp + 1;
1915                                         break;
1916 # endif
1917 // bb_process_escape_sequence does this now:
1918 //                              case 'e': case 'E':     /* \e \E = \033 */
1919 //                                      c = '\033';
1920 //                                      break;
1921                                 case 'x': case 'X': {
1922                                         char buf2[4];
1923                                         for (l = 0; l < 3;) {
1924                                                 unsigned h;
1925                                                 buf2[l++] = *prmt_ptr;
1926                                                 buf2[l] = '\0';
1927                                                 h = strtoul(buf2, &pbuf, 16);
1928                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1929                                                         buf2[--l] = '\0';
1930                                                         break;
1931                                                 }
1932                                                 prmt_ptr++;
1933                                         }
1934                                         c = (char)strtoul(buf2, NULL, 16);
1935                                         if (c == 0)
1936                                                 c = '?';
1937                                         pbuf = cbuf;
1938                                         break;
1939                                 }
1940                                 case '[': case ']':
1941                                         if (c == flg_not_length) {
1942                                                 /* Toggle '['/']' hex 5b/5d */
1943                                                 flg_not_length ^= 6;
1944                                                 continue;
1945                                         }
1946                                         break;
1947                                 } /* switch */
1948                         } /* if */
1949                 } /* if */
1950                 cbuf[0] = c;
1951                 {
1952                         int n = strlen(pbuf);
1953                         prmt_size += n;
1954                         if (c == '\n')
1955                                 cmdedit_prmt_len = 0;
1956                         else if (flg_not_length != ']') {
1957 #if 0 /*ENABLE_UNICODE_SUPPORT*/
1958 /* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
1959 /* FIXME */
1960                                 cmdedit_prmt_len += unicode_strwidth(pbuf);
1961 #else
1962                                 cmdedit_prmt_len += n;
1963 #endif
1964                         }
1965                 }
1966                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_size+1), pbuf);
1967                 free(free_me);
1968         } /* while */
1969
1970 # if ENABLE_USERNAME_OR_HOMEDIR
1971         if (cwd_buf != (char *)bb_msg_unknown)
1972                 free(cwd_buf);
1973 # endif
1974         cmdedit_prompt = prmt_mem_ptr;
1975         put_prompt();
1976 }
1977 #endif
1978
1979 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1980 {
1981         cmdedit_termw = w;
1982         if (redraw_flg) {
1983                 /* new y for current cursor */
1984                 int new_y = (cursor + cmdedit_prmt_len) / w;
1985                 /* redraw */
1986                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1987                 fflush_all();
1988         }
1989 }
1990
1991 static void win_changed(int nsig)
1992 {
1993         int sv_errno = errno;
1994         unsigned width;
1995
1996         get_terminal_width_height(0, &width, NULL);
1997 //FIXME: cmdedit_setwidth() -> redraw() -> printf() -> KABOOM! (we are in signal handler!)
1998         cmdedit_setwidth(width, /*redraw_flg:*/ nsig);
1999
2000         errno = sv_errno;
2001 }
2002
2003 static int lineedit_read_key(char *read_key_buffer, int timeout)
2004 {
2005         int64_t ic;
2006 #if ENABLE_UNICODE_SUPPORT
2007         char unicode_buf[MB_CUR_MAX + 1];
2008         int unicode_idx = 0;
2009 #endif
2010
2011         while (1) {
2012                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
2013                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
2014                  * insist on full MB_CUR_MAX buffer to declare input like
2015                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
2016                  *
2017                  * Note: read_key sets errno to 0 on success.
2018                  */
2019                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
2020                 if (errno) {
2021 #if ENABLE_UNICODE_SUPPORT
2022                         if (errno == EAGAIN && unicode_idx != 0)
2023                                 goto pushback;
2024 #endif
2025                         break;
2026                 }
2027
2028 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2029                 if ((int32_t)ic == KEYCODE_CURSOR_POS
2030                  && S.sent_ESC_br6n
2031                 ) {
2032                         S.sent_ESC_br6n = 0;
2033                         if (cursor == 0) { /* otherwise it may be bogus */
2034                                 int col = ((ic >> 32) & 0x7fff) - 1;
2035                                 /*
2036                                  * Is col > cmdedit_prmt_len?
2037                                  * If yes (terminal says cursor is farther to the right
2038                                  * of where we think it should be),
2039                                  * the prompt wasn't printed starting at col 1,
2040                                  * there was additional text before it.
2041                                  */
2042                                 if ((int)(col - cmdedit_prmt_len) > 0) {
2043                                         /* Fix our understanding of current x position */
2044                                         cmdedit_x += (col - cmdedit_prmt_len);
2045                                         while (cmdedit_x >= cmdedit_termw) {
2046                                                 cmdedit_x -= cmdedit_termw;
2047                                                 cmdedit_y++;
2048                                         }
2049                                 }
2050                         }
2051                         continue;
2052                 }
2053 #endif
2054
2055 #if ENABLE_UNICODE_SUPPORT
2056                 if (unicode_status == UNICODE_ON) {
2057                         wchar_t wc;
2058
2059                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
2060                                 break;
2061                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
2062
2063                         unicode_buf[unicode_idx++] = ic;
2064                         unicode_buf[unicode_idx] = '\0';
2065                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
2066                                 /* Not (yet?) a valid unicode char */
2067                                 if (unicode_idx < MB_CUR_MAX) {
2068                                         timeout = 50;
2069                                         continue;
2070                                 }
2071  pushback:
2072                                 /* Invalid sequence. Save all "bad bytes" except first */
2073                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
2074 # if !ENABLE_UNICODE_PRESERVE_BROKEN
2075                                 ic = CONFIG_SUBST_WCHAR;
2076 # else
2077                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
2078 # endif
2079                         } else {
2080                                 /* Valid unicode char, return its code */
2081                                 ic = wc;
2082                         }
2083                 }
2084 #endif
2085                 break;
2086         }
2087
2088         return ic;
2089 }
2090
2091 #if ENABLE_UNICODE_BIDI_SUPPORT
2092 static int isrtl_str(void)
2093 {
2094         int idx = cursor;
2095
2096         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
2097                 idx++;
2098         return unicode_bidi_isrtl(command_ps[idx]);
2099 }
2100 #else
2101 # define isrtl_str() 0
2102 #endif
2103
2104 /* leave out the "vi-mode"-only case labels if vi editing isn't
2105  * configured. */
2106 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
2107
2108 /* convert uppercase ascii to equivalent control char, for readability */
2109 #undef CTRL
2110 #define CTRL(a) ((a) & ~0x40)
2111
2112 enum {
2113         VI_CMDMODE_BIT = 0x40000000,
2114         /* 0x80000000 bit flags KEYCODE_xxx */
2115 };
2116
2117 #if ENABLE_FEATURE_REVERSE_SEARCH
2118 /* Mimic readline Ctrl-R reverse history search.
2119  * When invoked, it shows the following prompt:
2120  * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
2121  * and typing results in search being performed:
2122  * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
2123  * Search is performed by looking at progressively older lines in history.
2124  * Ctrl-R again searches for the next match in history.
2125  * Backspace deletes last matched char.
2126  * Control keys exit search and return to normal editing (at current history line).
2127  */
2128 static int32_t reverse_i_search(void)
2129 {
2130         char match_buf[128]; /* for user input */
2131         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2132         const char *matched_history_line;
2133         const char *saved_prompt;
2134         unsigned saved_prmt_len;
2135         int32_t ic;
2136
2137         matched_history_line = NULL;
2138         read_key_buffer[0] = 0;
2139         match_buf[0] = '\0';
2140
2141         /* Save and replace the prompt */
2142         saved_prompt = cmdedit_prompt;
2143         saved_prmt_len = cmdedit_prmt_len;
2144         goto set_prompt;
2145
2146         while (1) {
2147                 int h;
2148                 unsigned match_buf_len = strlen(match_buf);
2149
2150                 fflush_all();
2151 //FIXME: correct timeout?
2152                 ic = lineedit_read_key(read_key_buffer, -1);
2153
2154                 switch (ic) {
2155                 case CTRL('R'): /* searching for the next match */
2156                         break;
2157
2158                 case '\b':
2159                 case '\x7f':
2160                         /* Backspace */
2161                         if (unicode_status == UNICODE_ON) {
2162                                 while (match_buf_len != 0) {
2163                                         uint8_t c = match_buf[--match_buf_len];
2164                                         if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
2165                                                 break; /* yes */
2166                                 }
2167                         } else {
2168                                 if (match_buf_len != 0)
2169                                         match_buf_len--;
2170                         }
2171                         match_buf[match_buf_len] = '\0';
2172                         break;
2173
2174                 default:
2175                         if (ic < ' '
2176                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2177                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2178                         ) {
2179                                 goto ret;
2180                         }
2181
2182                         /* Append this char */
2183 #if ENABLE_UNICODE_SUPPORT
2184                         if (unicode_status == UNICODE_ON) {
2185                                 mbstate_t mbstate = { 0 };
2186                                 char buf[MB_CUR_MAX + 1];
2187                                 int len = wcrtomb(buf, ic, &mbstate);
2188                                 if (len > 0) {
2189                                         buf[len] = '\0';
2190                                         if (match_buf_len + len < sizeof(match_buf))
2191                                                 strcpy(match_buf + match_buf_len, buf);
2192                                 }
2193                         } else
2194 #endif
2195                         if (match_buf_len < sizeof(match_buf) - 1) {
2196                                 match_buf[match_buf_len] = ic;
2197                                 match_buf[match_buf_len + 1] = '\0';
2198                         }
2199                         break;
2200                 } /* switch (ic) */
2201
2202                 /* Search in history for match_buf */
2203                 h = state->cur_history;
2204                 if (ic == CTRL('R'))
2205                         h--;
2206                 while (h >= 0) {
2207                         if (state->history[h]) {
2208                                 char *match = strstr(state->history[h], match_buf);
2209                                 if (match) {
2210                                         state->cur_history = h;
2211                                         matched_history_line = state->history[h];
2212                                         command_len = load_string(matched_history_line);
2213                                         cursor = match - matched_history_line;
2214 //FIXME: cursor position for Unicode case
2215
2216                                         free((char*)cmdedit_prompt);
2217  set_prompt:
2218                                         cmdedit_prompt = xasprintf("(reverse-i-search)'%s': ", match_buf);
2219                                         cmdedit_prmt_len = unicode_strwidth(cmdedit_prompt);
2220                                         goto do_redraw;
2221                                 }
2222                         }
2223                         h--;
2224                 }
2225
2226                 /* Not found */
2227                 match_buf[match_buf_len] = '\0';
2228                 beep();
2229                 continue;
2230
2231  do_redraw:
2232                 redraw(cmdedit_y, command_len - cursor);
2233         } /* while (1) */
2234
2235  ret:
2236         if (matched_history_line)
2237                 command_len = load_string(matched_history_line);
2238
2239         free((char*)cmdedit_prompt);
2240         cmdedit_prompt = saved_prompt;
2241         cmdedit_prmt_len = saved_prmt_len;
2242         redraw(cmdedit_y, command_len - cursor);
2243
2244         return ic;
2245 }
2246 #endif
2247
2248 /* maxsize must be >= 2.
2249  * Returns:
2250  * -1 on read errors or EOF, or on bare Ctrl-D,
2251  * 0  on ctrl-C (the line entered is still returned in 'command'),
2252  * >0 length of input string, including terminating '\n'
2253  */
2254 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize, int timeout)
2255 {
2256         int len;
2257 #if ENABLE_FEATURE_TAB_COMPLETION
2258         smallint lastWasTab = 0;
2259 #endif
2260         smallint break_out = 0;
2261 #if ENABLE_FEATURE_EDITING_VI
2262         smallint vi_cmdmode = 0;
2263 #endif
2264         struct termios initial_settings;
2265         struct termios new_settings;
2266         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2267
2268         INIT_S();
2269
2270         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
2271          || (initial_settings.c_lflag & (ECHO|ICANON)) == ICANON
2272         ) {
2273                 /* Happens when e.g. stty -echo was run before.
2274                  * But if ICANON is not set, we don't come here.
2275                  * (example: interactive python ^Z-backgrounded,
2276                  * tty is still in "raw mode").
2277                  */
2278                 parse_and_put_prompt(prompt);
2279                 /* fflush_all(); - done by parse_and_put_prompt */
2280                 if (fgets(command, maxsize, stdin) == NULL)
2281                         len = -1; /* EOF or error */
2282                 else
2283                         len = strlen(command);
2284                 DEINIT_S();
2285                 return len;
2286         }
2287
2288         init_unicode();
2289
2290 // FIXME: audit & improve this
2291         if (maxsize > MAX_LINELEN)
2292                 maxsize = MAX_LINELEN;
2293         S.maxsize = maxsize;
2294
2295         /* With zero flags, no other fields are ever used */
2296         state = st ? st : (line_input_t*) &const_int_0;
2297 #if MAX_HISTORY > 0
2298 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
2299         if (state->hist_file)
2300                 if (state->cnt_history == 0)
2301                         load_history(state);
2302 # endif
2303         if (state->flags & DO_HISTORY)
2304                 state->cur_history = state->cnt_history;
2305 #endif
2306
2307         /* prepare before init handlers */
2308         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
2309         command_len = 0;
2310 #if ENABLE_UNICODE_SUPPORT
2311         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
2312 #else
2313         command_ps = command;
2314         command[0] = '\0';
2315 #endif
2316 #define command command_must_not_be_used
2317
2318         new_settings = initial_settings;
2319         /* ~ICANON: unbuffered input (most c_cc[] are disabled, VMIN/VTIME are enabled) */
2320         /* ~ECHO, ~ECHONL: turn off echoing, including newline echoing */
2321         /* ~ISIG: turn off INTR (ctrl-C), QUIT, SUSP */
2322         new_settings.c_lflag &= ~(ICANON | ECHO | ECHONL | ISIG);
2323         /* reads would block only if < 1 char is available */
2324         new_settings.c_cc[VMIN] = 1;
2325         /* no timeout (reads block forever) */
2326         new_settings.c_cc[VTIME] = 0;
2327         /* Should be not needed if ISIG is off: */
2328         /* Turn off CTRL-C */
2329         /* new_settings.c_cc[VINTR] = _POSIX_VDISABLE; */
2330         tcsetattr_stdin_TCSANOW(&new_settings);
2331
2332 #if ENABLE_USERNAME_OR_HOMEDIR
2333         {
2334                 struct passwd *entry;
2335
2336                 entry = getpwuid(geteuid());
2337                 if (entry) {
2338                         user_buf = xstrdup(entry->pw_name);
2339                         home_pwd_buf = xstrdup(entry->pw_dir);
2340                 }
2341         }
2342 #endif
2343
2344 #if 0
2345         for (i = 0; i <= state->max_history; i++)
2346                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2347         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2348 #endif
2349
2350         /* Print out the command prompt, optionally ask where cursor is */
2351         parse_and_put_prompt(prompt);
2352         ask_terminal();
2353
2354         /* Install window resize handler (NB: after *all* init is complete) */
2355 //FIXME: save entire sigaction!
2356         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
2357         win_changed(0); /* get initial window size */
2358
2359         read_key_buffer[0] = 0;
2360         while (1) {
2361                 /*
2362                  * The emacs and vi modes share much of the code in the big
2363                  * command loop.  Commands entered when in vi's command mode
2364                  * (aka "escape mode") get an extra bit added to distinguish
2365                  * them - this keeps them from being self-inserted. This
2366                  * clutters the big switch a bit, but keeps all the code
2367                  * in one place.
2368                  */
2369                 int32_t ic, ic_raw;
2370
2371                 fflush_all();
2372                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2373
2374 #if ENABLE_FEATURE_REVERSE_SEARCH
2375  again:
2376 #endif
2377 #if ENABLE_FEATURE_EDITING_VI
2378                 newdelflag = 1;
2379                 if (vi_cmdmode) {
2380                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2381                          * change ic if it contains one of them: */
2382                         ic |= VI_CMDMODE_BIT;
2383                 }
2384 #endif
2385
2386                 switch (ic) {
2387                 case '\n':
2388                 case '\r':
2389                 vi_case('\n'|VI_CMDMODE_BIT:)
2390                 vi_case('\r'|VI_CMDMODE_BIT:)
2391                         /* Enter */
2392                         goto_new_line();
2393                         break_out = 1;
2394                         break;
2395                 case CTRL('A'):
2396                 vi_case('0'|VI_CMDMODE_BIT:)
2397                         /* Control-a -- Beginning of line */
2398                         input_backward(cursor);
2399                         break;
2400                 case CTRL('B'):
2401                 vi_case('h'|VI_CMDMODE_BIT:)
2402                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2403                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2404                         input_backward(1); /* Move back one character */
2405                         break;
2406                 case CTRL('E'):
2407                 vi_case('$'|VI_CMDMODE_BIT:)
2408                         /* Control-e -- End of line */
2409                         put_till_end_and_adv_cursor();
2410                         break;
2411                 case CTRL('F'):
2412                 vi_case('l'|VI_CMDMODE_BIT:)
2413                 vi_case(' '|VI_CMDMODE_BIT:)
2414                         input_forward(); /* Move forward one character */
2415                         break;
2416                 case '\b':   /* ^H */
2417                 case '\x7f': /* DEL */
2418                         if (!isrtl_str())
2419                                 input_backspace();
2420                         else
2421                                 input_delete(0);
2422                         break;
2423                 case KEYCODE_DELETE:
2424                         if (!isrtl_str())
2425                                 input_delete(0);
2426                         else
2427                                 input_backspace();
2428                         break;
2429 #if ENABLE_FEATURE_TAB_COMPLETION
2430                 case '\t':
2431                         input_tab(&lastWasTab);
2432                         break;
2433 #endif
2434                 case CTRL('K'):
2435                         /* Control-k -- clear to end of line */
2436                         command_ps[cursor] = BB_NUL;
2437                         command_len = cursor;
2438                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2439                         break;
2440                 case CTRL('L'):
2441                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2442                         /* Control-l -- clear screen */
2443                         printf(ESC"[H"); /* cursor to top,left */
2444                         redraw(0, command_len - cursor);
2445                         break;
2446 #if MAX_HISTORY > 0
2447                 case CTRL('N'):
2448                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2449                 vi_case('j'|VI_CMDMODE_BIT:)
2450                         /* Control-n -- Get next command in history */
2451                         if (get_next_history())
2452                                 goto rewrite_line;
2453                         break;
2454                 case CTRL('P'):
2455                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2456                 vi_case('k'|VI_CMDMODE_BIT:)
2457                         /* Control-p -- Get previous command from history */
2458                         if (get_previous_history())
2459                                 goto rewrite_line;
2460                         break;
2461 #endif
2462                 case CTRL('U'):
2463                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2464                         /* Control-U -- Clear line before cursor */
2465                         if (cursor) {
2466                                 command_len -= cursor;
2467                                 memmove(command_ps, command_ps + cursor,
2468                                         (command_len + 1) * sizeof(command_ps[0]));
2469                                 redraw(cmdedit_y, command_len);
2470                         }
2471                         break;
2472                 case CTRL('W'):
2473                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2474                         /* Control-W -- Remove the last word */
2475                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2476                                 input_backspace();
2477                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2478                                 input_backspace();
2479                         break;
2480 #if ENABLE_FEATURE_REVERSE_SEARCH
2481                 case CTRL('R'):
2482                         ic = ic_raw = reverse_i_search();
2483                         goto again;
2484 #endif
2485
2486 #if ENABLE_FEATURE_EDITING_VI
2487                 case 'i'|VI_CMDMODE_BIT:
2488                         vi_cmdmode = 0;
2489                         break;
2490                 case 'I'|VI_CMDMODE_BIT:
2491                         input_backward(cursor);
2492                         vi_cmdmode = 0;
2493                         break;
2494                 case 'a'|VI_CMDMODE_BIT:
2495                         input_forward();
2496                         vi_cmdmode = 0;
2497                         break;
2498                 case 'A'|VI_CMDMODE_BIT:
2499                         put_till_end_and_adv_cursor();
2500                         vi_cmdmode = 0;
2501                         break;
2502                 case 'x'|VI_CMDMODE_BIT:
2503                         input_delete(1);
2504                         break;
2505                 case 'X'|VI_CMDMODE_BIT:
2506                         if (cursor > 0) {
2507                                 input_backward(1);
2508                                 input_delete(1);
2509                         }
2510                         break;
2511                 case 'W'|VI_CMDMODE_BIT:
2512                         vi_Word_motion(1);
2513                         break;
2514                 case 'w'|VI_CMDMODE_BIT:
2515                         vi_word_motion(1);
2516                         break;
2517                 case 'E'|VI_CMDMODE_BIT:
2518                         vi_End_motion();
2519                         break;
2520                 case 'e'|VI_CMDMODE_BIT:
2521                         vi_end_motion();
2522                         break;
2523                 case 'B'|VI_CMDMODE_BIT:
2524                         vi_Back_motion();
2525                         break;
2526                 case 'b'|VI_CMDMODE_BIT:
2527                         vi_back_motion();
2528                         break;
2529                 case 'C'|VI_CMDMODE_BIT:
2530                         vi_cmdmode = 0;
2531                         /* fall through */
2532                 case 'D'|VI_CMDMODE_BIT:
2533                         goto clear_to_eol;
2534
2535                 case 'c'|VI_CMDMODE_BIT:
2536                         vi_cmdmode = 0;
2537                         /* fall through */
2538                 case 'd'|VI_CMDMODE_BIT: {
2539                         int nc, sc;
2540
2541                         ic = lineedit_read_key(read_key_buffer, timeout);
2542                         if (errno) /* error */
2543                                 goto return_error_indicator;
2544                         if (ic == ic_raw) { /* "cc", "dd" */
2545                                 input_backward(cursor);
2546                                 goto clear_to_eol;
2547                                 break;
2548                         }
2549
2550                         sc = cursor;
2551                         switch (ic) {
2552                         case 'w':
2553                         case 'W':
2554                         case 'e':
2555                         case 'E':
2556                                 switch (ic) {
2557                                 case 'w':   /* "dw", "cw" */
2558                                         vi_word_motion(vi_cmdmode);
2559                                         break;
2560                                 case 'W':   /* 'dW', 'cW' */
2561                                         vi_Word_motion(vi_cmdmode);
2562                                         break;
2563                                 case 'e':   /* 'de', 'ce' */
2564                                         vi_end_motion();
2565                                         input_forward();
2566                                         break;
2567                                 case 'E':   /* 'dE', 'cE' */
2568                                         vi_End_motion();
2569                                         input_forward();
2570                                         break;
2571                                 }
2572                                 nc = cursor;
2573                                 input_backward(cursor - sc);
2574                                 while (nc-- > cursor)
2575                                         input_delete(1);
2576                                 break;
2577                         case 'b':  /* "db", "cb" */
2578                         case 'B':  /* implemented as B */
2579                                 if (ic == 'b')
2580                                         vi_back_motion();
2581                                 else
2582                                         vi_Back_motion();
2583                                 while (sc-- > cursor)
2584                                         input_delete(1);
2585                                 break;
2586                         case ' ':  /* "d ", "c " */
2587                                 input_delete(1);
2588                                 break;
2589                         case '$':  /* "d$", "c$" */
2590  clear_to_eol:
2591                                 while (cursor < command_len)
2592                                         input_delete(1);
2593                                 break;
2594                         }
2595                         break;
2596                 }
2597                 case 'p'|VI_CMDMODE_BIT:
2598                         input_forward();
2599                         /* fallthrough */
2600                 case 'P'|VI_CMDMODE_BIT:
2601                         put();
2602                         break;
2603                 case 'r'|VI_CMDMODE_BIT:
2604 //FIXME: unicode case?
2605                         ic = lineedit_read_key(read_key_buffer, timeout);
2606                         if (errno) /* error */
2607                                 goto return_error_indicator;
2608                         if (ic < ' ' || ic > 255) {
2609                                 beep();
2610                         } else {
2611                                 command_ps[cursor] = ic;
2612                                 bb_putchar(ic);
2613                                 bb_putchar('\b');
2614                         }
2615                         break;
2616                 case '\x1b': /* ESC */
2617                         if (state->flags & VI_MODE) {
2618                                 /* insert mode --> command mode */
2619                                 vi_cmdmode = 1;
2620                                 input_backward(1);
2621                         }
2622                         /* Handle a few ESC-<key> combinations the same way
2623                          * standard readline bindings (IOW: bash) do.
2624                          * Often, Alt-<key> generates ESC-<key>.
2625                          */
2626                         ic = lineedit_read_key(read_key_buffer, 50);
2627                         switch (ic) {
2628                                 //case KEYCODE_LEFT: - bash doesn't do this
2629                                 case 'b':
2630                                         ctrl_left();
2631                                         break;
2632                                 //case KEYCODE_RIGHT: - bash doesn't do this
2633                                 case 'f':
2634                                         ctrl_right();
2635                                         break;
2636                                 //case KEYCODE_DELETE: - bash doesn't do this
2637                                 case 'd':  /* Alt-D */
2638                                 {
2639                                         /* Delete word forward */
2640                                         int nc, sc = cursor;
2641                                         ctrl_right();
2642                                         nc = cursor - sc;
2643                                         input_backward(nc);
2644                                         while (--nc >= 0)
2645                                                 input_delete(1);
2646                                         break;
2647                                 }
2648                                 case '\b':   /* Alt-Backspace(?) */
2649                                 case '\x7f': /* Alt-Backspace(?) */
2650                                 //case 'w': - bash doesn't do this
2651                                 {
2652                                         /* Delete word backward */
2653                                         int sc = cursor;
2654                                         ctrl_left();
2655                                         while (sc-- > cursor)
2656                                                 input_delete(1);
2657                                         break;
2658                                 }
2659                         }
2660                         break;
2661 #endif /* FEATURE_COMMAND_EDITING_VI */
2662
2663 #if MAX_HISTORY > 0
2664                 case KEYCODE_UP:
2665                         if (get_previous_history())
2666                                 goto rewrite_line;
2667                         beep();
2668                         break;
2669                 case KEYCODE_DOWN:
2670                         if (!get_next_history())
2671                                 break;
2672  rewrite_line:
2673                         /* Rewrite the line with the selected history item */
2674                         /* change command */
2675                         command_len = load_string(state->history[state->cur_history] ?
2676                                         state->history[state->cur_history] : "");
2677                         /* redraw and go to eol (bol, in vi) */
2678                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2679                         break;
2680 #endif
2681                 case KEYCODE_RIGHT:
2682                         input_forward();
2683                         break;
2684                 case KEYCODE_LEFT:
2685                         input_backward(1);
2686                         break;
2687                 case KEYCODE_CTRL_LEFT:
2688                 case KEYCODE_ALT_LEFT: /* bash doesn't do it */
2689                         ctrl_left();
2690                         break;
2691                 case KEYCODE_CTRL_RIGHT:
2692                 case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
2693                         ctrl_right();
2694                         break;
2695                 case KEYCODE_HOME:
2696                         input_backward(cursor);
2697                         break;
2698                 case KEYCODE_END:
2699                         put_till_end_and_adv_cursor();
2700                         break;
2701
2702                 default:
2703                         if (initial_settings.c_cc[VINTR] != 0
2704                          && ic_raw == initial_settings.c_cc[VINTR]
2705                         ) {
2706                                 /* Ctrl-C (usually) - stop gathering input */
2707                                 goto_new_line();
2708                                 command_len = 0;
2709                                 break_out = -1; /* "do not append '\n'" */
2710                                 break;
2711                         }
2712                         if (initial_settings.c_cc[VEOF] != 0
2713                          && ic_raw == initial_settings.c_cc[VEOF]
2714                         ) {
2715                                 /* Ctrl-D (usually) - delete one character,
2716                                  * or exit if len=0 and no chars to delete */
2717                                 if (command_len == 0) {
2718                                         errno = 0;
2719
2720                 case -1: /* error (e.g. EIO when tty is destroyed) */
2721  IF_FEATURE_EDITING_VI(return_error_indicator:)
2722                                         break_out = command_len = -1;
2723                                         break;
2724                                 }
2725                                 input_delete(0);
2726                                 break;
2727                         }
2728 //                      /* Control-V -- force insert of next char */
2729 //                      if (c == CTRL('V')) {
2730 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2731 //                                      goto return_error_indicator;
2732 //                              if (c == 0) {
2733 //                                      beep();
2734 //                                      break;
2735 //                              }
2736 //                      }
2737                         if (ic < ' '
2738                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2739                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2740                         ) {
2741                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2742                                  * and vi mode ignores unexpected chars.
2743                                  * Otherwise, we are here if ic is a
2744                                  * control char or an unhandled ESC sequence,
2745                                  * which is also ignored.
2746                                  */
2747                                 break;
2748                         }
2749                         if ((int)command_len >= (maxsize - 2)) {
2750                                 /* Not enough space for the char and EOL */
2751                                 break;
2752                         }
2753
2754                         command_len++;
2755                         if (cursor == (command_len - 1)) {
2756                                 /* We are at the end, append */
2757                                 command_ps[cursor] = ic;
2758                                 command_ps[cursor + 1] = BB_NUL;
2759                                 put_cur_glyph_and_inc_cursor();
2760                                 if (unicode_bidi_isrtl(ic))
2761                                         input_backward(1);
2762                         } else {
2763                                 /* In the middle, insert */
2764                                 int sc = cursor;
2765
2766                                 memmove(command_ps + sc + 1, command_ps + sc,
2767                                         (command_len - sc) * sizeof(command_ps[0]));
2768                                 command_ps[sc] = ic;
2769                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2770                                 if (!isrtl_str())
2771                                         sc++; /* no */
2772                                 put_till_end_and_adv_cursor();
2773                                 /* to prev x pos + 1 */
2774                                 input_backward(cursor - sc);
2775                         }
2776                         break;
2777                 } /* switch (ic) */
2778
2779                 if (break_out)
2780                         break;
2781
2782 #if ENABLE_FEATURE_TAB_COMPLETION
2783                 if (ic_raw != '\t')
2784                         lastWasTab = 0;
2785 #endif
2786         } /* while (1) */
2787
2788 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2789         if (S.sent_ESC_br6n) {
2790                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2791                  * We sent "ESC [ 6 n", but got '\n' first, and
2792                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2793                  * It's bad already and not much can be done with it
2794                  * (it _will_ be visible for the next process to read stdin),
2795                  * but without this delay it even shows up on the screen
2796                  * as garbage because we restore echo settings with tcsetattr
2797                  * before it comes in. UGLY!
2798                  */
2799                 usleep(20*1000);
2800         }
2801 #endif
2802
2803 /* End of bug-catching "command_must_not_be_used" trick */
2804 #undef command
2805
2806 #if ENABLE_UNICODE_SUPPORT
2807         command[0] = '\0';
2808         if (command_len > 0)
2809                 command_len = save_string(command, maxsize - 1);
2810         free(command_ps);
2811 #endif
2812
2813         if (command_len > 0) {
2814                 remember_in_history(command);
2815         }
2816
2817         if (break_out > 0) {
2818                 command[command_len++] = '\n';
2819                 command[command_len] = '\0';
2820         }
2821
2822 #if ENABLE_FEATURE_TAB_COMPLETION
2823         free_tab_completion_data();
2824 #endif
2825
2826         /* restore initial_settings */
2827         tcsetattr_stdin_TCSANOW(&initial_settings);
2828         /* restore SIGWINCH handler */
2829         signal(SIGWINCH, previous_SIGWINCH_handler);
2830         fflush_all();
2831
2832         len = command_len;
2833         DEINIT_S();
2834
2835         return len; /* can't return command_len, DEINIT_S() destroys it */
2836 }
2837
2838 #else  /* !FEATURE_EDITING */
2839
2840 #undef read_line_input
2841 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2842 {
2843         fputs(prompt, stdout);
2844         fflush_all();
2845         if (!fgets(command, maxsize, stdin))
2846                 return -1;
2847         return strlen(command);
2848 }
2849
2850 #endif  /* !FEATURE_EDITING */
2851
2852
2853 /*
2854  * Testing
2855  */
2856
2857 #ifdef TEST
2858
2859 #include <locale.h>
2860
2861 const char *applet_name = "debug stuff usage";
2862
2863 int main(int argc, char **argv)
2864 {
2865         char buff[MAX_LINELEN];
2866         char *prompt =
2867 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2868                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2869                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2870                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2871 #else
2872                 "% ";
2873 #endif
2874
2875         while (1) {
2876                 int l;
2877                 l = read_line_input(prompt, buff);
2878                 if (l <= 0 || buff[l-1] != '\n')
2879                         break;
2880                 buff[l-1] = '\0';
2881                 printf("*** read_line_input() returned line =%s=\n", buff);
2882         }
2883         printf("*** read_line_input() detect ^D\n");
2884         return 0;
2885 }
2886
2887 #endif  /* TEST */