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 #include "libbb.h"
  43 #include "unicode.h"
  44
  45 #ifdef TEST
  46 # define ENABLE_FEATURE_EDITING 0
  47 # define ENABLE_FEATURE_TAB_COMPLETION 0
  48 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  49 #endif
  50
  51
  52 /* Entire file (except TESTing part) sits inside this #if */
  53 #if ENABLE_FEATURE_EDITING
  54
  55
  56 #define ENABLE_USERNAME_OR_HOMEDIR \
  57         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  58 #define IF_USERNAME_OR_HOMEDIR(...)
  59 #if ENABLE_USERNAME_OR_HOMEDIR
  60 # undef IF_USERNAME_OR_HOMEDIR
  61 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  62 #endif
  63
  64
  65 #undef CHAR_T
  66 #if ENABLE_UNICODE_SUPPORT
  67 # define BB_NUL ((wchar_t)0)
  68 # define CHAR_T wchar_t
  69 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  70 # if ENABLE_FEATURE_EDITING_VI
  71 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  72 # endif
  73 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  74 # undef isspace
  75 # undef isalnum
  76 # undef ispunct
  77 # undef isprint
  78 # define isspace isspace_must_not_be_used
  79 # define isalnum isalnum_must_not_be_used
  80 # define ispunct ispunct_must_not_be_used
  81 # define isprint isprint_must_not_be_used
  82 #else
  83 # define BB_NUL '\0'
  84 # define CHAR_T char
  85 # define BB_isspace(c) isspace(c)
  86 # define BB_isalnum(c) isalnum(c)
  87 # define BB_ispunct(c) ispunct(c)
  88 #endif
  89 #if ENABLE_UNICODE_PRESERVE_BROKEN
  90 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
  91 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
  92 #else
  93 # define unicode_is_raw_byte(wc)     0
  94 #endif
  95
  96
  97 #define SEQ_CLEAR_TILL_END_OF_SCREEN "\033[J"
  98 //#define SEQ_CLEAR_TILL_END_OF_LINE   "\033[K"
  99
 100
 101 enum {
 102         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 103                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 104                       : 0x7ff0
 105 };
 106
 107 #if ENABLE_USERNAME_OR_HOMEDIR
 108 static const char null_str[] ALIGN1 = "";
 109 #endif
 110
 111 /* We try to minimize both static and stack usage. */
 112 struct lineedit_statics {
 113         line_input_t *state;
 114
 115         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 116         sighandler_t previous_SIGWINCH_handler;
 117
 118         unsigned cmdedit_x;        /* real x (col) terminal position */
 119         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 120         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 121
 122         unsigned cursor;
 123         int command_len; /* must be signed */
 124         /* signed maxsize: we want x in "if (x > S.maxsize)"
 125          * to _not_ be promoted to unsigned */
 126         int maxsize;
 127         CHAR_T *command_ps;
 128
 129         const char *cmdedit_prompt;
 130 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 131         int num_ok_lines; /* = 1; */
 132 #endif
 133
 134 #if ENABLE_USERNAME_OR_HOMEDIR
 135         char *user_buf;
 136         char *home_pwd_buf; /* = (char*)null_str; */
 137 #endif
 138
 139 #if ENABLE_FEATURE_TAB_COMPLETION
 140         char **matches;
 141         unsigned num_matches;
 142 #endif
 143
 144 #if ENABLE_FEATURE_EDITING_VI
 145 # define DELBUFSIZ 128
 146         CHAR_T *delptr;
 147         smallint newdelflag;     /* whether delbuf should be reused yet */
 148         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 149 #endif
 150 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 151         smallint sent_ESC_br6n;
 152 #endif
 153
 154         /* Formerly these were big buffers on stack: */
 155 #if ENABLE_FEATURE_TAB_COMPLETION
 156         char input_tab__matchBuf[MAX_LINELEN];
 157         int16_t find_match__int_buf[MAX_LINELEN + 1]; /* need to have 9 bits at least */
 158 #endif
 159 };
 160
 161 /* See lineedit_ptr_hack.c */
 162 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 163
 164 #define S (*lineedit_ptr_to_statics)
 165 #define state            (S.state           )
 166 #define cmdedit_termw    (S.cmdedit_termw   )
 167 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 168 #define cmdedit_x        (S.cmdedit_x       )
 169 #define cmdedit_y        (S.cmdedit_y       )
 170 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 171 #define cursor           (S.cursor          )
 172 #define command_len      (S.command_len     )
 173 #define command_ps       (S.command_ps      )
 174 #define cmdedit_prompt   (S.cmdedit_prompt  )
 175 #define num_ok_lines     (S.num_ok_lines    )
 176 #define user_buf         (S.user_buf        )
 177 #define home_pwd_buf     (S.home_pwd_buf    )
 178 #define matches          (S.matches         )
 179 #define num_matches      (S.num_matches     )
 180 #define delptr           (S.delptr          )
 181 #define newdelflag       (S.newdelflag      )
 182 #define delbuf           (S.delbuf          )
 183
 184 #define INIT_S() do { \
 185         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 186         barrier(); \
 187         cmdedit_termw = 80; \
 188         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
 189         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 190 } while (0)
 191 static void deinit_S(void)
 192 {
 193 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 194         /* This one is allocated only if FANCY_PROMPT is on
 195          * (otherwise it points to verbatim prompt (NOT malloced)) */
 196         free((char*)cmdedit_prompt);
 197 #endif
 198 #if ENABLE_USERNAME_OR_HOMEDIR
 199         free(user_buf);
 200         if (home_pwd_buf != null_str)
 201                 free(home_pwd_buf);
 202 #endif
 203         free(lineedit_ptr_to_statics);
 204 }
 205 #define DEINIT_S() deinit_S()
 206
 207
 208 #if ENABLE_UNICODE_SUPPORT
 209 static size_t load_string(const char *src, int maxsize)
 210 {
 211         ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
 212         if (len < 0)
 213                 len = 0;
 214         command_ps[len] = BB_NUL;
 215         return len;
 216 }
 217 static unsigned save_string(char *dst, unsigned maxsize)
 218 {
 219 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 220         ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 221         if (len < 0)
 222                 len = 0;
 223         dst[len] = '\0';
 224         return len;
 225 # else
 226         unsigned dstpos = 0;
 227         unsigned srcpos = 0;
 228
 229         maxsize--;
 230         while (dstpos < maxsize) {
 231                 wchar_t wc;
 232                 int n = srcpos;
 233
 234                 /* Convert up to 1st invalid byte (or up to end) */
 235                 while ((wc = command_ps[srcpos]) != BB_NUL
 236                     && !unicode_is_raw_byte(wc)
 237                 ) {
 238                         srcpos++;
 239                 }
 240                 command_ps[srcpos] = BB_NUL;
 241                 n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 242                 if (n < 0) /* should not happen */
 243                         break;
 244                 dstpos += n;
 245                 if (wc == BB_NUL) /* usually is */
 246                         break;
 247
 248                 /* We do have invalid byte here! */
 249                 command_ps[srcpos] = wc; /* restore it */
 250                 srcpos++;
 251                 if (dstpos == maxsize)
 252                         break;
 253                 dst[dstpos++] = (char) wc;
 254         }
 255         dst[dstpos] = '\0';
 256         return dstpos;
 257 # endif
 258 }
 259 /* I thought just fputwc(c, stdout) would work. But no... */
 260 static void BB_PUTCHAR(wchar_t c)
 261 {
 262         char buf[MB_CUR_MAX + 1];
 263         mbstate_t mbst = { 0 };
 264         ssize_t len;
 265
 266         len = wcrtomb(buf, c, &mbst);
 267         if (len > 0) {
 268                 buf[len] = '\0';
 269                 fputs(buf, stdout);
 270         }
 271 }
 272 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 273 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 274 # else
 275 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 276 #  define adjust_width_and_validate_wc(width_adj, wc) \
 277         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 278 # endif
 279 {
 280         int w = 1;
 281
 282         if (unicode_status == UNICODE_ON) {
 283                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 284                         /* note: also true for unicode_is_raw_byte(wc) */
 285                         goto subst;
 286                 }
 287                 w = wcwidth(wc);
 288                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 289                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 290                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 291                 ) {
 292  subst:
 293                         w = 1;
 294                         wc = CONFIG_SUBST_WCHAR;
 295                 }
 296         }
 297
 298 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 299         *width_adj += w;
 300 #endif
 301         return wc;
 302 }
 303 #else /* !UNICODE */
 304 static size_t load_string(const char *src, int maxsize)
 305 {
 306         safe_strncpy(command_ps, src, maxsize);
 307         return strlen(command_ps);
 308 }
 309 # if ENABLE_FEATURE_TAB_COMPLETION
 310 static void save_string(char *dst, unsigned maxsize)
 311 {
 312         safe_strncpy(dst, command_ps, maxsize);
 313 }
 314 # endif
 315 # define BB_PUTCHAR(c) bb_putchar(c)
 316 /* Should never be called: */
 317 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 318 #endif
 319
 320
 321 /* Put 'command_ps[cursor]', cursor++.
 322  * Advance cursor on screen. If we reached right margin, scroll text up
 323  * and remove terminal margin effect by printing 'next_char' */
 324 #define HACK_FOR_WRONG_WIDTH 1
 325 static void put_cur_glyph_and_inc_cursor(void)
 326 {
 327         CHAR_T c = command_ps[cursor];
 328         unsigned width = 0;
 329         int ofs_to_right;
 330
 331         if (c == BB_NUL) {
 332                 /* erase character after end of input string */
 333                 c = ' ';
 334         } else {
 335                 /* advance cursor only if we aren't at the end yet */
 336                 cursor++;
 337                 if (unicode_status == UNICODE_ON) {
 338                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 339                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 340                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 341                 } else {
 342                         cmdedit_x++;
 343                 }
 344         }
 345
 346         ofs_to_right = cmdedit_x - cmdedit_termw;
 347         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 348                 /* c fits on this line */
 349                 BB_PUTCHAR(c);
 350         }
 351
 352         if (ofs_to_right >= 0) {
 353                 /* we go to the next line */
 354 #if HACK_FOR_WRONG_WIDTH
 355                 /* This works better if our idea of term width is wrong
 356                  * and it is actually wider (often happens on serial lines).
 357                  * Printing CR,LF *forces* cursor to next line.
 358                  * OTOH if terminal width is correct AND terminal does NOT
 359                  * have automargin (IOW: it is moving cursor to next line
 360                  * by itself (which is wrong for VT-10x terminals)),
 361                  * this will break things: there will be one extra empty line */
 362                 puts("\r"); /* + implicit '\n' */
 363 #else
 364                 /* VT-10x terminals don't wrap cursor to next line when last char
 365                  * on the line is printed - cursor stays "over" this char.
 366                  * Need to print _next_ char too (first one to appear on next line)
 367                  * to make cursor move down to next line.
 368                  */
 369                 /* Works ok only if cmdedit_termw is correct. */
 370                 c = command_ps[cursor];
 371                 if (c == BB_NUL)
 372                         c = ' ';
 373                 BB_PUTCHAR(c);
 374                 bb_putchar('\b');
 375 #endif
 376                 cmdedit_y++;
 377                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 378                         width = 0;
 379                 } else { /* ofs_to_right > 0 */
 380                         /* wide char c didn't fit on prev line */
 381                         BB_PUTCHAR(c);
 382                 }
 383                 cmdedit_x = width;
 384         }
 385 }
 386
 387 /* Move to end of line (by printing all chars till the end) */
 388 static void put_till_end_and_adv_cursor(void)
 389 {
 390         while (cursor < command_len)
 391                 put_cur_glyph_and_inc_cursor();
 392 }
 393
 394 /* Go to the next line */
 395 static void goto_new_line(void)
 396 {
 397         put_till_end_and_adv_cursor();
 398         if (cmdedit_x != 0)
 399                 bb_putchar('\n');
 400 }
 401
 402 static void beep(void)
 403 {
 404         bb_putchar('\007');
 405 }
 406
 407 static void put_prompt(void)
 408 {
 409         unsigned w;
 410
 411         fputs(cmdedit_prompt, stdout);
 412         fflush_all();
 413         cursor = 0;
 414         w = cmdedit_termw; /* read volatile var once */
 415         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 416         cmdedit_x = cmdedit_prmt_len % w;
 417 }
 418
 419 /* Move back one character */
 420 /* (optimized for slow terminals) */
 421 static void input_backward(unsigned num)
 422 {
 423         if (num > cursor)
 424                 num = cursor;
 425         if (num == 0)
 426                 return;
 427         cursor -= num;
 428
 429         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 430          && unicode_status == UNICODE_ON
 431         ) {
 432                 /* correct NUM to be equal to _screen_ width */
 433                 int n = num;
 434                 num = 0;
 435                 while (--n >= 0)
 436                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 437                 if (num == 0)
 438                         return;
 439         }
 440
 441         if (cmdedit_x >= num) {
 442                 cmdedit_x -= num;
 443                 if (num <= 4) {
 444                         /* This is longer by 5 bytes on x86.
 445                          * Also gets miscompiled for ARM users
 446                          * (busybox.net/bugs/view.php?id=2274).
 447                          * printf(("\b\b\b\b" + 4) - num);
 448                          * return;
 449                          */
 450                         do {
 451                                 bb_putchar('\b');
 452                         } while (--num);
 453                         return;
 454                 }
 455                 printf("\033[%uD", num);
 456                 return;
 457         }
 458
 459         /* Need to go one or more lines up */
 460         if (ENABLE_UNICODE_WIDE_WCHARS) {
 461                 /* With wide chars, it is hard to "backtrack"
 462                  * and reliably figure out where to put cursor.
 463                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 464                  * |prompt: <><> |
 465                  * |<><><><><><> |
 466                  * |_            |
 467                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 468                  * We need to go up one line, and then - how do we know that
 469                  * we need to go *10* positions to the right? Because
 470                  * |prompt: <>#<>|
 471                  * |<><><>#<><><>|
 472                  * |_            |
 473                  * in this situation we need to go *11* positions to the right.
 474                  *
 475                  * A simpler thing to do is to redraw everything from the start
 476                  * up to new cursor position (which is already known):
 477                  */
 478                 unsigned sv_cursor;
 479                 /* go to 1st column; go up to first line */
 480                 printf("\r" "\033[%uA", cmdedit_y);
 481                 cmdedit_y = 0;
 482                 sv_cursor = cursor;
 483                 put_prompt(); /* sets cursor to 0 */
 484                 while (cursor < sv_cursor)
 485                         put_cur_glyph_and_inc_cursor();
 486         } else {
 487                 int lines_up;
 488                 unsigned width;
 489                 /* num = chars to go back from the beginning of current line: */
 490                 num -= cmdedit_x;
 491                 width = cmdedit_termw; /* read volatile var once */
 492                 /* num=1...w: one line up, w+1...2w: two, etc: */
 493                 lines_up = 1 + (num - 1) / width;
 494                 cmdedit_x = (width * cmdedit_y - num) % width;
 495                 cmdedit_y -= lines_up;
 496                 /* go to 1st column; go up */
 497                 printf("\r" "\033[%uA", lines_up);
 498                 /* go to correct column.
 499                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 500                  * need to *make sure* we skip it if cmdedit_x == 0 */
 501                 if (cmdedit_x)
 502                         printf("\033[%uC", cmdedit_x);
 503         }
 504 }
 505
 506 /* draw prompt, editor line, and clear tail */
 507 static void redraw(int y, int back_cursor)
 508 {
 509         if (y > 0) /* up y lines */
 510                 printf("\033[%uA", y);
 511         bb_putchar('\r');
 512         put_prompt();
 513         put_till_end_and_adv_cursor();
 514         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 515         input_backward(back_cursor);
 516 }
 517
 518 /* Delete the char in front of the cursor, optionally saving it
 519  * for later putback */
 520 #if !ENABLE_FEATURE_EDITING_VI
 521 static void input_delete(void)
 522 #define input_delete(save) input_delete()
 523 #else
 524 static void input_delete(int save)
 525 #endif
 526 {
 527         int j = cursor;
 528
 529         if (j == (int)command_len)
 530                 return;
 531
 532 #if ENABLE_FEATURE_EDITING_VI
 533         if (save) {
 534                 if (newdelflag) {
 535                         delptr = delbuf;
 536                         newdelflag = 0;
 537                 }
 538                 if ((delptr - delbuf) < DELBUFSIZ)
 539                         *delptr++ = command_ps[j];
 540         }
 541 #endif
 542
 543         memmove(command_ps + j, command_ps + j + 1,
 544                         /* (command_len + 1 [because of NUL]) - (j + 1)
 545                          * simplified into (command_len - j) */
 546                         (command_len - j) * sizeof(command_ps[0]));
 547         command_len--;
 548         put_till_end_and_adv_cursor();
 549         /* Last char is still visible, erase it (and more) */
 550         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 551         input_backward(cursor - j);     /* back to old pos cursor */
 552 }
 553
 554 #if ENABLE_FEATURE_EDITING_VI
 555 static void put(void)
 556 {
 557         int ocursor;
 558         int j = delptr - delbuf;
 559
 560         if (j == 0)
 561                 return;
 562         ocursor = cursor;
 563         /* open hole and then fill it */
 564         memmove(command_ps + cursor + j, command_ps + cursor,
 565                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 566         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 567         command_len += j;
 568         put_till_end_and_adv_cursor();
 569         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 570 }
 571 #endif
 572
 573 /* Delete the char in back of the cursor */
 574 static void input_backspace(void)
 575 {
 576         if (cursor > 0) {
 577                 input_backward(1);
 578                 input_delete(0);
 579         }
 580 }
 581
 582 /* Move forward one character */
 583 static void input_forward(void)
 584 {
 585         if (cursor < command_len)
 586                 put_cur_glyph_and_inc_cursor();
 587 }
 588
 589 #if ENABLE_FEATURE_TAB_COMPLETION
 590
 591 static void free_tab_completion_data(void)
 592 {
 593         if (matches) {
 594                 while (num_matches)
 595                         free(matches[--num_matches]);
 596                 free(matches);
 597                 matches = NULL;
 598         }
 599 }
 600
 601 static void add_match(char *matched)
 602 {
 603         matches = xrealloc_vector(matches, 4, num_matches);
 604         matches[num_matches] = matched;
 605         num_matches++;
 606 }
 607
 608 #if ENABLE_FEATURE_USERNAME_COMPLETION
 609 /* Replace "~user/..." with "/homedir/...".
 610  * The parameter is malloced, free it or return it
 611  * unchanged if no user is matched.
 612  */
 613 static char *username_path_completion(char *ud)
 614 {
 615         struct passwd *entry;
 616         char *tilde_name = ud;
 617         char *home = NULL;
 618
 619         ud++; /* skip ~ */
 620         if (*ud == '/') {       /* "~/..." */
 621                 home = home_pwd_buf;
 622         } else {
 623                 /* "~user/..." */
 624                 ud = strchr(ud, '/');
 625                 *ud = '\0';           /* "~user" */
 626                 entry = getpwnam(tilde_name + 1);
 627                 *ud = '/';            /* restore "~user/..." */
 628                 if (entry)
 629                         home = entry->pw_dir;
 630         }
 631         if (home) {
 632                 ud = concat_path_file(home, ud);
 633                 free(tilde_name);
 634                 tilde_name = ud;
 635         }
 636         return tilde_name;
 637 }
 638
 639 /* ~use<tab> - find all users with this prefix.
 640  * Return the length of the prefix used for matching.
 641  */
 642 static NOINLINE unsigned complete_username(const char *ud)
 643 {
 644         /* Using _r function to avoid pulling in static buffers */
 645         char line_buff[256];
 646         struct passwd pwd;
 647         struct passwd *result;
 648         unsigned userlen;
 649
 650         ud++; /* skip ~ */
 651         userlen = strlen(ud);
 652
 653         setpwent();
 654         while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
 655                 /* Null usernames should result in all users as possible completions. */
 656                 if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
 657                         add_match(xasprintf("~%s/", pwd.pw_name));
 658                 }
 659         }
 660         endpwent();
 661
 662         return 1 + userlen;
 663 }
 664 #endif  /* FEATURE_USERNAME_COMPLETION */
 665
 666 enum {
 667         FIND_EXE_ONLY = 0,
 668         FIND_DIR_ONLY = 1,
 669         FIND_FILE_ONLY = 2,
 670 };
 671
 672 static int path_parse(char ***p)
 673 {
 674         int npth;
 675         const char *pth;
 676         char *tmp;
 677         char **res;
 678
 679         if (state->flags & WITH_PATH_LOOKUP)
 680                 pth = state->path_lookup;
 681         else
 682                 pth = getenv("PATH");
 683
 684         /* PATH="" or PATH=":"? */
 685         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 686                 return 1;
 687
 688         tmp = (char*)pth;
 689         npth = 1; /* path component count */
 690         while (1) {
 691                 tmp = strchr(tmp, ':');
 692                 if (!tmp)
 693                         break;
 694                 tmp++;
 695                 if (*tmp == '\0')
 696                         break;  /* :<empty> */
 697                 npth++;
 698         }
 699
 700         *p = res = xmalloc(npth * sizeof(res[0]));
 701         res[0] = tmp = xstrdup(pth);
 702         npth = 1;
 703         while (1) {
 704                 tmp = strchr(tmp, ':');
 705                 if (!tmp)
 706                         break;
 707                 *tmp++ = '\0'; /* ':' -> '\0' */
 708                 if (*tmp == '\0')
 709                         break; /* :<empty> */
 710                 res[npth++] = tmp;
 711         }
 712         return npth;
 713 }
 714
 715 /* Complete command, directory or file name.
 716  * Return the length of the prefix used for matching.
 717  */
 718 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 719 {
 720         char *path1[1];
 721         char **paths = path1;
 722         int npaths;
 723         int i;
 724         unsigned pf_len;
 725         const char *pfind;
 726         char *dirbuf = NULL;
 727
 728         npaths = 1;
 729         path1[0] = (char*)".";
 730
 731         pfind = strrchr(command, '/');
 732         if (!pfind) {
 733                 if (type == FIND_EXE_ONLY)
 734                         npaths = path_parse(&paths);
 735                 pfind = command;
 736         } else {
 737                 /* point to 'l' in "..../last_component" */
 738                 pfind++;
 739                 /* dirbuf = ".../.../.../" */
 740                 dirbuf = xstrndup(command, pfind - command);
 741 #if ENABLE_FEATURE_USERNAME_COMPLETION
 742                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 743                         dirbuf = username_path_completion(dirbuf);
 744 #endif
 745                 path1[0] = dirbuf;
 746         }
 747         pf_len = strlen(pfind);
 748
 749         for (i = 0; i < npaths; i++) {
 750                 DIR *dir;
 751                 struct dirent *next;
 752                 struct stat st;
 753                 char *found;
 754
 755                 dir = opendir(paths[i]);
 756                 if (!dir)
 757                         continue; /* don't print an error */
 758
 759                 while ((next = readdir(dir)) != NULL) {
 760                         const char *name_found = next->d_name;
 761
 762                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 763                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 764                                 continue;
 765                         /* match? */
 766                         if (strncmp(name_found, pfind, pf_len) != 0)
 767                                 continue; /* no */
 768
 769                         found = concat_path_file(paths[i], name_found);
 770                         /* NB: stat() first so that we see is it a directory;
 771                          * but if that fails, use lstat() so that
 772                          * we still match dangling links */
 773                         if (stat(found, &st) && lstat(found, &st))
 774                                 goto cont; /* hmm, remove in progress? */
 775
 776                         /* save only name if we scan PATH */
 777                         if (paths[i] != dirbuf)
 778                                 strcpy(found, name_found);
 779
 780                         if (S_ISDIR(st.st_mode)) {
 781                                 unsigned len1 = strlen(found);
 782                                 /* name is a directory */
 783                                 if (found[len1-1] != '/') {
 784                                         found = xrealloc(found, len1 + 2);
 785                                         found[len1] = '/';
 786                                         found[len1 + 1] = '\0';
 787                                 }
 788                         } else {
 789                                 /* skip files if looking for dirs only (example: cd) */
 790                                 if (type == FIND_DIR_ONLY)
 791                                         goto cont;
 792                         }
 793                         /* add it to the list */
 794                         add_match(found);
 795                         continue;
 796  cont:
 797                         free(found);
 798                 }
 799                 closedir(dir);
 800         } /* for every path */
 801
 802         if (paths != path1) {
 803                 free(paths[0]); /* allocated memory is only in first member */
 804                 free(paths);
 805         } else if (dirbuf) {
 806                 pf_len += strlen(dirbuf);
 807                 free(dirbuf);
 808         }
 809
 810         return pf_len;
 811 }
 812
 813 /* build_match_prefix:
 814  * On entry, matchBuf contains everything up to cursor at the moment <tab>
 815  * was pressed. This function looks at it, figures out what part of it
 816  * constitutes the command/file/directory prefix to use for completion,
 817  * and rewrites matchBuf to contain only that part.
 818  */
 819 /* Helpers: */
 820 /* QUOT is used on elements of int_buf[], which are bytes,
 821  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 822  */
 823 #define QUOT (UCHAR_MAX+1)
 824 #define int_buf (S.find_match__int_buf)
 825 #define dbg_bmp 0
 826 static void remove_chunk(int beg, int end)
 827 {
 828         /* beg must be <= end */
 829         if (beg == end)
 830                 return;
 831
 832         while ((int_buf[beg] = int_buf[end]) != 0)
 833                 beg++, end++;
 834
 835         if (dbg_bmp) {
 836                 int i;
 837                 for (i = 0; int_buf[i]; i++)
 838                         bb_putchar((unsigned char)int_buf[i]);
 839                 bb_putchar('\n');
 840         }
 841 }
 842 static NOINLINE int build_match_prefix(char *matchBuf)
 843 {
 844         int i, j;
 845         int command_mode;
 846 /*      Were local, but it used too much stack */
 847 /*      int16_t int_buf[MAX_LINELEN + 1]; */
 848
 849         if (dbg_bmp) printf("\n%s\n", matchBuf);
 850
 851         i = 0;
 852         while ((int_buf[i] = (unsigned char)matchBuf[i]) != '\0')
 853                 i++;
 854
 855         /* Mark every \c as "quoted c" */
 856         for (i = j = 0; matchBuf[i]; i++, j++) {
 857                 if (matchBuf[i] == '\\') {
 858                         remove_chunk(j, j + 1);
 859                         int_buf[j] |= QUOT;
 860                         i++;
 861                 }
 862         }
 863         /* Quote-mark "chars" and 'chars', drop delimiters */
 864         {
 865                 int in_quote = 0;
 866                 i = 0;
 867                 while (int_buf[i]) {
 868                         int cur = int_buf[i];
 869                         if (!cur)
 870                                 break;
 871                         if (cur == '\'' || cur == '"') {
 872                                 if (!in_quote || (cur == in_quote)) {
 873                                         in_quote ^= cur;
 874                                         remove_chunk(i, i + 1);
 875                                         continue;
 876                                 }
 877                         }
 878                         if (in_quote)
 879                                 int_buf[i] = cur | QUOT;
 880                         i++;
 881                 }
 882         }
 883
 884         /* Remove everything up to command delimiters:
 885          * ';' ';;' '&' '|' '&&' '||',
 886          * but careful with '>&' '<&' '>|'
 887          */
 888         for (i = 0; int_buf[i]; i++) {
 889                 int cur = int_buf[i];
 890                 if (cur == ';' || cur == '&' || cur == '|') {
 891                         int prev = i ? int_buf[i - 1] : 0;
 892                         if (cur == '&' && (prev == '>' || prev == '<')) {
 893                                 continue;
 894                         } else if (cur == '|' && prev == '>') {
 895                                 continue;
 896                         }
 897                         remove_chunk(0, i + 1 + (cur == int_buf[i + 1]));
 898                         i = -1;  /* back to square 1 */
 899                 }
 900         }
 901         /* Remove all `cmd` */
 902         for (i = 0; int_buf[i]; i++) {
 903                 if (int_buf[i] == '`') {
 904                         for (j = i + 1; int_buf[j]; j++) {
 905                                 if (int_buf[j] == '`') {
 906                                         /* `cmd` should count as a word:
 907                                          * `cmd` c<tab> should search for files c*,
 908                                          * not commands c*. Therefore we don't drop
 909                                          * `cmd` entirely, we replace it with single `.
 910                                          */
 911                                         remove_chunk(i, j);
 912                                         goto next;
 913                                 }
 914                         }
 915                         /* No closing ` - command mode, remove all up to ` */
 916                         remove_chunk(0, i + 1);
 917                         break;
 918  next: ;
 919                 }
 920         }
 921
 922         /* Remove "cmd (" and "cmd {"
 923          * Example: "if { c<tab>"
 924          * In this example, c should be matched as command pfx.
 925          */
 926         for (i = 0; int_buf[i]; i++) {
 927                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 928                         remove_chunk(0, i + 1);
 929                         i = -1;  /* hack increment */
 930                 }
 931         }
 932
 933         /* Remove leading unquoted spaces */
 934         for (i = 0; int_buf[i]; i++)
 935                 if (int_buf[i] != ' ')
 936                         break;
 937         remove_chunk(0, i);
 938
 939         /* Determine completion mode */
 940         command_mode = FIND_EXE_ONLY;
 941         for (i = 0; int_buf[i]; i++) {
 942                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 943                         if (int_buf[i] == ' '
 944                          && command_mode == FIND_EXE_ONLY
 945                          && (char)int_buf[0] == 'c'
 946                          && (char)int_buf[1] == 'd'
 947                          && i == 2 /* -> int_buf[2] == ' ' */
 948                         ) {
 949                                 command_mode = FIND_DIR_ONLY;
 950                         } else {
 951                                 command_mode = FIND_FILE_ONLY;
 952                                 break;
 953                         }
 954                 }
 955         }
 956         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 957
 958         /* Remove everything except last word */
 959         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
 960                 continue;
 961         for (--i; i >= 0; i--) {
 962                 int cur = int_buf[i];
 963                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
 964                         remove_chunk(0, i + 1);
 965                         break;
 966                 }
 967         }
 968
 969         /* Store only match prefix */
 970         i = 0;
 971         while ((matchBuf[i] = int_buf[i]) != '\0')
 972                 i++;
 973         if (dbg_bmp) printf("final matchBuf:'%s'\n", matchBuf);
 974
 975         return command_mode;
 976 }
 977 #undef int_buf
 978
 979 /*
 980  * Display by column (original idea from ls applet,
 981  * very optimized by me [Vladimir] :)
 982  */
 983 static void showfiles(void)
 984 {
 985         int ncols, row;
 986         int column_width = 0;
 987         int nfiles = num_matches;
 988         int nrows = nfiles;
 989         int l;
 990
 991         /* find the longest file name - use that as the column width */
 992         for (row = 0; row < nrows; row++) {
 993                 l = unicode_strwidth(matches[row]);
 994                 if (column_width < l)
 995                         column_width = l;
 996         }
 997         column_width += 2;              /* min space for columns */
 998         ncols = cmdedit_termw / column_width;
 999
1000         if (ncols > 1) {
1001                 nrows /= ncols;
1002                 if (nfiles % ncols)
1003                         nrows++;        /* round up fractionals */
1004         } else {
1005                 ncols = 1;
1006         }
1007         for (row = 0; row < nrows; row++) {
1008                 int n = row;
1009                 int nc;
1010
1011                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1012                         printf("%s%-*s", matches[n],
1013                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1014                         );
1015                 }
1016                 if (ENABLE_UNICODE_SUPPORT)
1017                         puts(printable_string(NULL, matches[n]));
1018                 else
1019                         puts(matches[n]);
1020         }
1021 }
1022
1023 static char *add_quote_for_spec_chars(char *found)
1024 {
1025         int l = 0;
1026         char *s = xzalloc((strlen(found) + 1) * 2);
1027
1028         while (*found) {
1029                 if (strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", *found))
1030                         s[l++] = '\\';
1031                 s[l++] = *found++;
1032         }
1033         /* s[l] = '\0'; - already is */
1034         return s;
1035 }
1036
1037 /* Do TAB completion */
1038 static NOINLINE void input_tab(smallint *lastWasTab)
1039 {
1040         if (!(state->flags & TAB_COMPLETION))
1041                 return;
1042
1043         if (!*lastWasTab) {
1044                 char *tmp;
1045                 size_t len_found;
1046 /*              char matchBuf[MAX_LINELEN]; */
1047 #define matchBuf (S.input_tab__matchBuf)
1048                 /* Length of string used for matching */
1049                 unsigned match_pfx_len = match_pfx_len;
1050                 int find_type;
1051 #if ENABLE_UNICODE_SUPPORT
1052                 /* cursor pos in command converted to multibyte form */
1053                 int cursor_mb;
1054 #endif
1055
1056                 *lastWasTab = 1;
1057
1058                 /* Make a local copy of the string --
1059                  * up to the position of the cursor */
1060 #if !ENABLE_UNICODE_SUPPORT
1061                 save_string(matchBuf, cursor + 1);
1062 #else
1063                 {
1064                         CHAR_T wc = command_ps[cursor];
1065                         command_ps[cursor] = BB_NUL;
1066                         save_string(matchBuf, MAX_LINELEN);
1067                         command_ps[cursor] = wc;
1068                         cursor_mb = strlen(matchBuf);
1069                 }
1070 #endif
1071                 tmp = matchBuf;
1072
1073                 find_type = build_match_prefix(matchBuf);
1074
1075                 /* Free up any memory already allocated */
1076                 free_tab_completion_data();
1077
1078 #if ENABLE_FEATURE_USERNAME_COMPLETION
1079                 /* If the word starts with `~' and there is no slash in the word,
1080                  * then try completing this word as a username. */
1081                 if (state->flags & USERNAME_COMPLETION)
1082                         if (matchBuf[0] == '~' && strchr(matchBuf, '/') == NULL)
1083                                 match_pfx_len = complete_username(matchBuf);
1084 #endif
1085                 /* Try to match a command in $PATH, or a directory, or a file */
1086                 if (!matches)
1087                         match_pfx_len = complete_cmd_dir_file(matchBuf, find_type);
1088                 /* Remove duplicates */
1089                 if (matches) {
1090                         unsigned i;
1091                         unsigned n = 0;
1092                         qsort_string_vector(matches, num_matches);
1093                         for (i = 0; i < num_matches - 1; ++i) {
1094                                 //if (matches[i] && matches[i+1]) { /* paranoia */
1095                                         if (strcmp(matches[i], matches[i+1]) == 0) {
1096                                                 free(matches[i]);
1097                                                 //matches[i] = NULL; /* paranoia */
1098                                         } else {
1099                                                 matches[n++] = matches[i];
1100                                         }
1101                                 //}
1102                         }
1103                         matches[n++] = matches[i];
1104                         num_matches = n;
1105                 }
1106                 /* Did we find exactly one match? */
1107                 if (num_matches != 1) { /* no */
1108                         char *tmp1;
1109                         beep();
1110                         if (!matches)
1111                                 return; /* no matches at all */
1112                         /* Find common prefix */
1113                         tmp1 = xstrdup(matches[0]);
1114                         for (tmp = tmp1; *tmp; tmp++) {
1115                                 unsigned n;
1116                                 for (n = 1; n < num_matches; n++) {
1117                                         if (matches[n][tmp - tmp1] != *tmp) {
1118                                                 goto stop;
1119                                         }
1120                                 }
1121                         }
1122  stop:
1123                         if (tmp1 == tmp) { /* have unique prefix? */
1124                                 free(tmp1); /* no */
1125                                 return;
1126                         }
1127                         *tmp = '\0';
1128                         tmp = add_quote_for_spec_chars(tmp1);
1129                         free(tmp1);
1130                         len_found = strlen(tmp);
1131                 } else {                        /* exactly one match */
1132                         /* Next <tab> is not a double-tab */
1133                         *lastWasTab = 0;
1134
1135                         tmp = add_quote_for_spec_chars(matches[0]);
1136                         len_found = strlen(tmp);
1137                         if (tmp[len_found-1] != '/') {
1138                                 tmp[len_found] = ' ';
1139                                 tmp[++len_found] = '\0';
1140                         }
1141                 }
1142
1143 #if !ENABLE_UNICODE_SUPPORT
1144                 /* Have space to place the match? */
1145                 /* The result consists of three parts with these lengths: */
1146                 /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1147                 /* it simplifies into: */
1148                 if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1149                         int pos;
1150                         /* save tail */
1151                         strcpy(matchBuf, &command_ps[cursor]);
1152                         /* add match and tail */
1153                         sprintf(&command_ps[cursor], "%s%s", tmp + match_pfx_len, matchBuf);
1154                         command_len = strlen(command_ps);
1155                         /* new pos */
1156                         pos = cursor + len_found - match_pfx_len;
1157                         /* write out the matched command */
1158                         redraw(cmdedit_y, command_len - pos);
1159                 }
1160 #else
1161                 {
1162                         char command[MAX_LINELEN];
1163                         int len = save_string(command, sizeof(command));
1164                         /* Have space to place the match? */
1165                         /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1166                         if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1167                                 int pos;
1168                                 /* save tail */
1169                                 strcpy(matchBuf, &command[cursor_mb]);
1170                                 /* where do we want to have cursor after all? */
1171                                 strcpy(&command[cursor_mb], tmp + match_pfx_len);
1172                                 len = load_string(command, S.maxsize);
1173                                 /* add match and tail */
1174                                 sprintf(&command[cursor_mb], "%s%s", tmp + match_pfx_len, matchBuf);
1175                                 command_len = load_string(command, S.maxsize);
1176                                 /* write out the matched command */
1177                                 /* paranoia: load_string can return 0 on conv error,
1178                                  * prevent passing pos = (0 - 12) to redraw */
1179                                 pos = command_len - len;
1180                                 redraw(cmdedit_y, pos >= 0 ? pos : 0);
1181                         }
1182                 }
1183 #endif
1184                 free(tmp);
1185 #undef matchBuf
1186         } else {
1187                 /* Ok -- the last char was a TAB.  Since they
1188                  * just hit TAB again, print a list of all the
1189                  * available choices... */
1190                 if (matches && num_matches > 0) {
1191                         /* changed by goto_new_line() */
1192                         int sav_cursor = cursor;
1193
1194                         /* Go to the next line */
1195                         goto_new_line();
1196                         showfiles();
1197                         redraw(0, command_len - sav_cursor);
1198                 }
1199         }
1200 }
1201
1202 #endif  /* FEATURE_TAB_COMPLETION */
1203
1204
1205 line_input_t* FAST_FUNC new_line_input_t(int flags)
1206 {
1207         line_input_t *n = xzalloc(sizeof(*n));
1208         n->flags = flags;
1209         return n;
1210 }
1211
1212
1213 #if MAX_HISTORY > 0
1214
1215 static void save_command_ps_at_cur_history(void)
1216 {
1217         if (command_ps[0] != BB_NUL) {
1218                 int cur = state->cur_history;
1219                 free(state->history[cur]);
1220
1221 # if ENABLE_UNICODE_SUPPORT
1222                 {
1223                         char tbuf[MAX_LINELEN];
1224                         save_string(tbuf, sizeof(tbuf));
1225                         state->history[cur] = xstrdup(tbuf);
1226                 }
1227 # else
1228                 state->history[cur] = xstrdup(command_ps);
1229 # endif
1230         }
1231 }
1232
1233 /* state->flags is already checked to be nonzero */
1234 static int get_previous_history(void)
1235 {
1236         if ((state->flags & DO_HISTORY) && state->cur_history) {
1237                 save_command_ps_at_cur_history();
1238                 state->cur_history--;
1239                 return 1;
1240         }
1241         beep();
1242         return 0;
1243 }
1244
1245 static int get_next_history(void)
1246 {
1247         if (state->flags & DO_HISTORY) {
1248                 if (state->cur_history < state->cnt_history) {
1249                         save_command_ps_at_cur_history(); /* save the current history line */
1250                         return ++state->cur_history;
1251                 }
1252         }
1253         beep();
1254         return 0;
1255 }
1256
1257 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1258 /* We try to ensure that concurrent additions to the history
1259  * do not overwrite each other.
1260  * Otherwise shell users get unhappy.
1261  *
1262  * History file is trimmed lazily, when it grows several times longer
1263  * than configured MAX_HISTORY lines.
1264  */
1265
1266 static void free_line_input_t(line_input_t *n)
1267 {
1268         int i = n->cnt_history;
1269         while (i > 0)
1270                 free(n->history[--i]);
1271         free(n);
1272 }
1273
1274 /* state->flags is already checked to be nonzero */
1275 static void load_history(line_input_t *st_parm)
1276 {
1277         char *temp_h[MAX_HISTORY];
1278         char *line;
1279         FILE *fp;
1280         unsigned idx, i, line_len;
1281
1282         /* NB: do not trash old history if file can't be opened */
1283
1284         fp = fopen_for_read(st_parm->hist_file);
1285         if (fp) {
1286                 /* clean up old history */
1287                 for (idx = st_parm->cnt_history; idx > 0;) {
1288                         idx--;
1289                         free(st_parm->history[idx]);
1290                         st_parm->history[idx] = NULL;
1291                 }
1292
1293                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1294                 memset(temp_h, 0, sizeof(temp_h));
1295                 st_parm->cnt_history_in_file = idx = 0;
1296                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1297                         if (line[0] == '\0') {
1298                                 free(line);
1299                                 continue;
1300                         }
1301                         free(temp_h[idx]);
1302                         temp_h[idx] = line;
1303                         st_parm->cnt_history_in_file++;
1304                         idx++;
1305                         if (idx == MAX_HISTORY)
1306                                 idx = 0;
1307                 }
1308                 fclose(fp);
1309
1310                 /* find first non-NULL temp_h[], if any */
1311                 if (st_parm->cnt_history_in_file) {
1312                         while (temp_h[idx] == NULL) {
1313                                 idx++;
1314                                 if (idx == MAX_HISTORY)
1315                                         idx = 0;
1316                         }
1317                 }
1318
1319                 /* copy temp_h[] to st_parm->history[] */
1320                 for (i = 0; i < MAX_HISTORY;) {
1321                         line = temp_h[idx];
1322                         if (!line)
1323                                 break;
1324                         idx++;
1325                         if (idx == MAX_HISTORY)
1326                                 idx = 0;
1327                         line_len = strlen(line);
1328                         if (line_len >= MAX_LINELEN)
1329                                 line[MAX_LINELEN-1] = '\0';
1330                         st_parm->history[i++] = line;
1331                 }
1332                 st_parm->cnt_history = i;
1333         }
1334 }
1335
1336 /* state->flags is already checked to be nonzero */
1337 static void save_history(char *str)
1338 {
1339         int fd;
1340         int len, len2;
1341
1342         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0666);
1343         if (fd < 0)
1344                 return;
1345         xlseek(fd, 0, SEEK_END); /* paranoia */
1346         len = strlen(str);
1347         str[len] = '\n'; /* we (try to) do atomic write */
1348         len2 = full_write(fd, str, len + 1);
1349         str[len] = '\0';
1350         close(fd);
1351         if (len2 != len + 1)
1352                 return; /* "wtf?" */
1353
1354         /* did we write so much that history file needs trimming? */
1355         state->cnt_history_in_file++;
1356         if (state->cnt_history_in_file > MAX_HISTORY * 4) {
1357                 FILE *fp;
1358                 char *new_name;
1359                 line_input_t *st_temp;
1360                 int i;
1361
1362                 /* we may have concurrently written entries from others.
1363                  * load them */
1364                 st_temp = new_line_input_t(state->flags);
1365                 st_temp->hist_file = state->hist_file;
1366                 load_history(st_temp);
1367
1368                 /* write out temp file and replace hist_file atomically */
1369                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1370                 fp = fopen_for_write(new_name);
1371                 if (fp) {
1372                         for (i = 0; i < st_temp->cnt_history; i++)
1373                                 fprintf(fp, "%s\n", st_temp->history[i]);
1374                         fclose(fp);
1375                         if (rename(new_name, state->hist_file) == 0)
1376                                 state->cnt_history_in_file = st_temp->cnt_history;
1377                 }
1378                 free(new_name);
1379                 free_line_input_t(st_temp);
1380         }
1381 }
1382 # else
1383 #  define load_history(a) ((void)0)
1384 #  define save_history(a) ((void)0)
1385 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1386
1387 static void remember_in_history(char *str)
1388 {
1389         int i;
1390
1391         if (!(state->flags & DO_HISTORY))
1392                 return;
1393         if (str[0] == '\0')
1394                 return;
1395         i = state->cnt_history;
1396         /* Don't save dupes */
1397         if (i && strcmp(state->history[i-1], str) == 0)
1398                 return;
1399
1400         free(state->history[MAX_HISTORY]); /* redundant, paranoia */
1401         state->history[MAX_HISTORY] = NULL; /* redundant, paranoia */
1402
1403         /* If history[] is full, remove the oldest command */
1404         /* we need to keep history[MAX_HISTORY] empty, hence >=, not > */
1405         if (i >= MAX_HISTORY) {
1406                 free(state->history[0]);
1407                 for (i = 0; i < MAX_HISTORY-1; i++)
1408                         state->history[i] = state->history[i+1];
1409                 /* i == MAX_HISTORY-1 */
1410         }
1411         /* i <= MAX_HISTORY-1 */
1412         state->history[i++] = xstrdup(str);
1413         /* i <= MAX_HISTORY */
1414         state->cur_history = i;
1415         state->cnt_history = i;
1416 # if MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
1417         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1418                 save_history(str);
1419 # endif
1420         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines++;)
1421 }
1422
1423 #else /* MAX_HISTORY == 0 */
1424 # define remember_in_history(a) ((void)0)
1425 #endif /* MAX_HISTORY */
1426
1427
1428 #if ENABLE_FEATURE_EDITING_VI
1429 /*
1430  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1431  */
1432 static void
1433 vi_Word_motion(int eat)
1434 {
1435         CHAR_T *command = command_ps;
1436
1437         while (cursor < command_len && !BB_isspace(command[cursor]))
1438                 input_forward();
1439         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1440                 input_forward();
1441 }
1442
1443 static void
1444 vi_word_motion(int eat)
1445 {
1446         CHAR_T *command = command_ps;
1447
1448         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1449                 while (cursor < command_len
1450                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1451                 ) {
1452                         input_forward();
1453                 }
1454         } else if (BB_ispunct(command[cursor])) {
1455                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1456                         input_forward();
1457         }
1458
1459         if (cursor < command_len)
1460                 input_forward();
1461
1462         if (eat) {
1463                 while (cursor < command_len && BB_isspace(command[cursor]))
1464                         input_forward();
1465         }
1466 }
1467
1468 static void
1469 vi_End_motion(void)
1470 {
1471         CHAR_T *command = command_ps;
1472
1473         input_forward();
1474         while (cursor < command_len && BB_isspace(command[cursor]))
1475                 input_forward();
1476         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1477                 input_forward();
1478 }
1479
1480 static void
1481 vi_end_motion(void)
1482 {
1483         CHAR_T *command = command_ps;
1484
1485         if (cursor >= command_len-1)
1486                 return;
1487         input_forward();
1488         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1489                 input_forward();
1490         if (cursor >= command_len-1)
1491                 return;
1492         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1493                 while (cursor < command_len-1
1494                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1495                 ) {
1496                         input_forward();
1497                 }
1498         } else if (BB_ispunct(command[cursor])) {
1499                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1500                         input_forward();
1501         }
1502 }
1503
1504 static void
1505 vi_Back_motion(void)
1506 {
1507         CHAR_T *command = command_ps;
1508
1509         while (cursor > 0 && BB_isspace(command[cursor-1]))
1510                 input_backward(1);
1511         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1512                 input_backward(1);
1513 }
1514
1515 static void
1516 vi_back_motion(void)
1517 {
1518         CHAR_T *command = command_ps;
1519
1520         if (cursor <= 0)
1521                 return;
1522         input_backward(1);
1523         while (cursor > 0 && BB_isspace(command[cursor]))
1524                 input_backward(1);
1525         if (cursor <= 0)
1526                 return;
1527         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1528                 while (cursor > 0
1529                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1530                 ) {
1531                         input_backward(1);
1532                 }
1533         } else if (BB_ispunct(command[cursor])) {
1534                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1535                         input_backward(1);
1536         }
1537 }
1538 #endif
1539
1540 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1541 static void ctrl_left(void)
1542 {
1543         CHAR_T *command = command_ps;
1544
1545         while (1) {
1546                 CHAR_T c;
1547
1548                 input_backward(1);
1549                 if (cursor == 0)
1550                         break;
1551                 c = command[cursor];
1552                 if (c != ' ' && !BB_ispunct(c)) {
1553                         /* we reached a "word" delimited by spaces/punct.
1554                          * go to its beginning */
1555                         while (1) {
1556                                 c = command[cursor - 1];
1557                                 if (c == ' ' || BB_ispunct(c))
1558                                         break;
1559                                 input_backward(1);
1560                                 if (cursor == 0)
1561                                         break;
1562                         }
1563                         break;
1564                 }
1565         }
1566 }
1567 static void ctrl_right(void)
1568 {
1569         CHAR_T *command = command_ps;
1570
1571         while (1) {
1572                 CHAR_T c;
1573
1574                 c = command[cursor];
1575                 if (c == BB_NUL)
1576                         break;
1577                 if (c != ' ' && !BB_ispunct(c)) {
1578                         /* we reached a "word" delimited by spaces/punct.
1579                          * go to its end + 1 */
1580                         while (1) {
1581                                 input_forward();
1582                                 c = command[cursor];
1583                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1584                                         break;
1585                         }
1586                         break;
1587                 }
1588                 input_forward();
1589         }
1590 }
1591
1592
1593 /*
1594  * read_line_input and its helpers
1595  */
1596
1597 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1598 static void ask_terminal(void)
1599 {
1600         /* Ask terminal where is the cursor now.
1601          * lineedit_read_key handles response and corrects
1602          * our idea of current cursor position.
1603          * Testcase: run "echo -n long_line_long_line_long_line",
1604          * then type in a long, wrapping command and try to
1605          * delete it using backspace key.
1606          * Note: we print it _after_ prompt, because
1607          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1608          */
1609         /* Problem: if there is buffered input on stdin,
1610          * the response will be delivered later,
1611          * possibly to an unsuspecting application.
1612          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1613          * Result:
1614          * ~/srcdevel/bbox/fix/busybox.t4 #
1615          * ~/srcdevel/bbox/fix/busybox.t4 #
1616          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1617          * ~/srcdevel/bbox/fix/busybox.t4 #
1618          *
1619          * Checking for input with poll only makes the race narrower,
1620          * I still can trigger it. Strace:
1621          *
1622          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1623          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1624          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1625          * poll([{fd=0, events=POLLIN}], 1, 4294967295) = 1 ([{fd=0, revents=POLLIN}])
1626          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1627          */
1628         struct pollfd pfd;
1629
1630         pfd.fd = STDIN_FILENO;
1631         pfd.events = POLLIN;
1632         if (safe_poll(&pfd, 1, 0) == 0) {
1633                 S.sent_ESC_br6n = 1;
1634                 fputs("\033" "[6n", stdout);
1635                 fflush_all(); /* make terminal see it ASAP! */
1636         }
1637 }
1638 #else
1639 #define ask_terminal() ((void)0)
1640 #endif
1641
1642 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1643 static void parse_and_put_prompt(const char *prmt_ptr)
1644 {
1645         cmdedit_prompt = prmt_ptr;
1646         cmdedit_prmt_len = strlen(prmt_ptr);
1647         put_prompt();
1648 }
1649 #else
1650 static void parse_and_put_prompt(const char *prmt_ptr)
1651 {
1652         int prmt_len = 0;
1653         size_t cur_prmt_len = 0;
1654         char flg_not_length = '[';
1655         char *prmt_mem_ptr = xzalloc(1);
1656         char *cwd_buf = xrealloc_getcwd_or_warn(NULL);
1657         char cbuf[2];
1658         char c;
1659         char *pbuf;
1660
1661         cmdedit_prmt_len = 0;
1662
1663         if (!cwd_buf) {
1664                 cwd_buf = (char *)bb_msg_unknown;
1665         }
1666
1667         cbuf[1] = '\0'; /* never changes */
1668
1669         while (*prmt_ptr) {
1670                 char *free_me = NULL;
1671
1672                 pbuf = cbuf;
1673                 c = *prmt_ptr++;
1674                 if (c == '\\') {
1675                         const char *cp = prmt_ptr;
1676                         int l;
1677
1678                         c = bb_process_escape_sequence(&prmt_ptr);
1679                         if (prmt_ptr == cp) {
1680                                 if (*cp == '\0')
1681                                         break;
1682                                 c = *prmt_ptr++;
1683
1684                                 switch (c) {
1685 # if ENABLE_USERNAME_OR_HOMEDIR
1686                                 case 'u':
1687                                         pbuf = user_buf ? user_buf : (char*)"";
1688                                         break;
1689 # endif
1690                                 case 'h':
1691                                         pbuf = free_me = safe_gethostname();
1692                                         *strchrnul(pbuf, '.') = '\0';
1693                                         break;
1694                                 case '$':
1695                                         c = (geteuid() == 0 ? '#' : '$');
1696                                         break;
1697 # if ENABLE_USERNAME_OR_HOMEDIR
1698                                 case 'w':
1699                                         /* /home/user[/something] -> ~[/something] */
1700                                         pbuf = cwd_buf;
1701                                         l = strlen(home_pwd_buf);
1702                                         if (l != 0
1703                                          && strncmp(home_pwd_buf, cwd_buf, l) == 0
1704                                          && (cwd_buf[l]=='/' || cwd_buf[l]=='\0')
1705                                          && strlen(cwd_buf + l) < PATH_MAX
1706                                         ) {
1707                                                 pbuf = free_me = xasprintf("~%s", cwd_buf + l);
1708                                         }
1709                                         break;
1710 # endif
1711                                 case 'W':
1712                                         pbuf = cwd_buf;
1713                                         cp = strrchr(pbuf, '/');
1714                                         if (cp != NULL && cp != pbuf)
1715                                                 pbuf += (cp-pbuf) + 1;
1716                                         break;
1717                                 case '!':
1718                                         pbuf = free_me = xasprintf("%d", num_ok_lines);
1719                                         break;
1720                                 case 'e': case 'E':     /* \e \E = \033 */
1721                                         c = '\033';
1722                                         break;
1723                                 case 'x': case 'X': {
1724                                         char buf2[4];
1725                                         for (l = 0; l < 3;) {
1726                                                 unsigned h;
1727                                                 buf2[l++] = *prmt_ptr;
1728                                                 buf2[l] = '\0';
1729                                                 h = strtoul(buf2, &pbuf, 16);
1730                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1731                                                         buf2[--l] = '\0';
1732                                                         break;
1733                                                 }
1734                                                 prmt_ptr++;
1735                                         }
1736                                         c = (char)strtoul(buf2, NULL, 16);
1737                                         if (c == 0)
1738                                                 c = '?';
1739                                         pbuf = cbuf;
1740                                         break;
1741                                 }
1742                                 case '[': case ']':
1743                                         if (c == flg_not_length) {
1744                                                 flg_not_length = (flg_not_length == '[' ? ']' : '[');
1745                                                 continue;
1746                                         }
1747                                         break;
1748                                 } /* switch */
1749                         } /* if */
1750                 } /* if */
1751                 cbuf[0] = c;
1752                 cur_prmt_len = strlen(pbuf);
1753                 prmt_len += cur_prmt_len;
1754                 if (flg_not_length != ']')
1755                         cmdedit_prmt_len += cur_prmt_len;
1756                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_len+1), pbuf);
1757                 free(free_me);
1758         } /* while */
1759
1760         if (cwd_buf != (char *)bb_msg_unknown)
1761                 free(cwd_buf);
1762         cmdedit_prompt = prmt_mem_ptr;
1763         put_prompt();
1764 }
1765 #endif
1766
1767 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1768 {
1769         cmdedit_termw = w;
1770         if (redraw_flg) {
1771                 /* new y for current cursor */
1772                 int new_y = (cursor + cmdedit_prmt_len) / w;
1773                 /* redraw */
1774                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1775                 fflush_all();
1776         }
1777 }
1778
1779 static void win_changed(int nsig)
1780 {
1781         int sv_errno = errno;
1782         unsigned width;
1783         get_terminal_width_height(0, &width, NULL);
1784         cmdedit_setwidth(width, nsig /* - just a yes/no flag */);
1785         if (nsig == SIGWINCH)
1786                 signal(SIGWINCH, win_changed); /* rearm ourself */
1787         errno = sv_errno;
1788 }
1789
1790 static int lineedit_read_key(char *read_key_buffer)
1791 {
1792         int64_t ic;
1793         int timeout = -1;
1794 #if ENABLE_UNICODE_SUPPORT
1795         char unicode_buf[MB_CUR_MAX + 1];
1796         int unicode_idx = 0;
1797 #endif
1798
1799         while (1) {
1800                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
1801                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
1802                  * insist on full MB_CUR_MAX buffer to declare input like
1803                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
1804                  *
1805                  * Note: read_key sets errno to 0 on success.
1806                  */
1807                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
1808                 if (errno) {
1809 #if ENABLE_UNICODE_SUPPORT
1810                         if (errno == EAGAIN && unicode_idx != 0)
1811                                 goto pushback;
1812 #endif
1813                         break;
1814                 }
1815
1816 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1817                 if ((int32_t)ic == KEYCODE_CURSOR_POS
1818                  && S.sent_ESC_br6n
1819                 ) {
1820                         S.sent_ESC_br6n = 0;
1821                         if (cursor == 0) { /* otherwise it may be bogus */
1822                                 int col = ((ic >> 32) & 0x7fff) - 1;
1823                                 if (col > cmdedit_prmt_len) {
1824                                         cmdedit_x += (col - cmdedit_prmt_len);
1825                                         while (cmdedit_x >= cmdedit_termw) {
1826                                                 cmdedit_x -= cmdedit_termw;
1827                                                 cmdedit_y++;
1828                                         }
1829                                 }
1830                         }
1831                         continue;
1832                 }
1833 #endif
1834
1835 #if ENABLE_UNICODE_SUPPORT
1836                 if (unicode_status == UNICODE_ON) {
1837                         wchar_t wc;
1838
1839                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
1840                                 break;
1841                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
1842
1843                         unicode_buf[unicode_idx++] = ic;
1844                         unicode_buf[unicode_idx] = '\0';
1845                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
1846                                 /* Not (yet?) a valid unicode char */
1847                                 if (unicode_idx < MB_CUR_MAX) {
1848                                         timeout = 50;
1849                                         continue;
1850                                 }
1851  pushback:
1852                                 /* Invalid sequence. Save all "bad bytes" except first */
1853                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
1854 # if !ENABLE_UNICODE_PRESERVE_BROKEN
1855                                 ic = CONFIG_SUBST_WCHAR;
1856 # else
1857                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
1858 # endif
1859                         } else {
1860                                 /* Valid unicode char, return its code */
1861                                 ic = wc;
1862                         }
1863                 }
1864 #endif
1865                 break;
1866         }
1867
1868         return ic;
1869 }
1870
1871 #if ENABLE_UNICODE_BIDI_SUPPORT
1872 static int isrtl_str(void)
1873 {
1874         int idx = cursor;
1875
1876         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
1877                 idx++;
1878         return unicode_bidi_isrtl(command_ps[idx]);
1879 }
1880 #else
1881 # define isrtl_str() 0
1882 #endif
1883
1884 /* leave out the "vi-mode"-only case labels if vi editing isn't
1885  * configured. */
1886 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
1887
1888 /* convert uppercase ascii to equivalent control char, for readability */
1889 #undef CTRL
1890 #define CTRL(a) ((a) & ~0x40)
1891
1892 /* maxsize must be >= 2.
1893  * Returns:
1894  * -1 on read errors or EOF, or on bare Ctrl-D,
1895  * 0  on ctrl-C (the line entered is still returned in 'command'),
1896  * >0 length of input string, including terminating '\n'
1897  */
1898 int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, line_input_t *st)
1899 {
1900         int len;
1901 #if ENABLE_FEATURE_TAB_COMPLETION
1902         smallint lastWasTab = 0;
1903 #endif
1904         smallint break_out = 0;
1905 #if ENABLE_FEATURE_EDITING_VI
1906         smallint vi_cmdmode = 0;
1907 #endif
1908         struct termios initial_settings;
1909         struct termios new_settings;
1910         char read_key_buffer[KEYCODE_BUFFER_SIZE];
1911
1912         INIT_S();
1913
1914         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
1915          || !(initial_settings.c_lflag & ECHO)
1916         ) {
1917                 /* Happens when e.g. stty -echo was run before */
1918                 parse_and_put_prompt(prompt);
1919                 /* fflush_all(); - done by parse_and_put_prompt */
1920                 if (fgets(command, maxsize, stdin) == NULL)
1921                         len = -1; /* EOF or error */
1922                 else
1923                         len = strlen(command);
1924                 DEINIT_S();
1925                 return len;
1926         }
1927
1928         init_unicode();
1929
1930 // FIXME: audit & improve this
1931         if (maxsize > MAX_LINELEN)
1932                 maxsize = MAX_LINELEN;
1933         S.maxsize = maxsize;
1934
1935         /* With null flags, no other fields are ever used */
1936         state = st ? st : (line_input_t*) &const_int_0;
1937 #if MAX_HISTORY > 0
1938 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1939         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1940                 if (state->cnt_history == 0)
1941                         load_history(state);
1942 # endif
1943         if (state->flags & DO_HISTORY)
1944                 state->cur_history = state->cnt_history;
1945 #endif
1946
1947         /* prepare before init handlers */
1948         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
1949         command_len = 0;
1950 #if ENABLE_UNICODE_SUPPORT
1951         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
1952 #else
1953         command_ps = command;
1954         command[0] = '\0';
1955 #endif
1956 #define command command_must_not_be_used
1957
1958         new_settings = initial_settings;
1959         new_settings.c_lflag &= ~ICANON;        /* unbuffered input */
1960         /* Turn off echoing and CTRL-C, so we can trap it */
1961         new_settings.c_lflag &= ~(ECHO | ECHONL | ISIG);
1962         /* Hmm, in linux c_cc[] is not parsed if ICANON is off */
1963         new_settings.c_cc[VMIN] = 1;
1964         new_settings.c_cc[VTIME] = 0;
1965         /* Turn off CTRL-C, so we can trap it */
1966 #ifndef _POSIX_VDISABLE
1967 # define _POSIX_VDISABLE '\0'
1968 #endif
1969         new_settings.c_cc[VINTR] = _POSIX_VDISABLE;
1970         tcsetattr_stdin_TCSANOW(&new_settings);
1971
1972         /* Now initialize things */
1973         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
1974         win_changed(0); /* do initial resizing */
1975 #if ENABLE_USERNAME_OR_HOMEDIR
1976         {
1977                 struct passwd *entry;
1978
1979                 entry = getpwuid(geteuid());
1980                 if (entry) {
1981                         user_buf = xstrdup(entry->pw_name);
1982                         home_pwd_buf = xstrdup(entry->pw_dir);
1983                 }
1984         }
1985 #endif
1986
1987 #if 0
1988         for (i = 0; i <= MAX_HISTORY; i++)
1989                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
1990         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
1991 #endif
1992
1993         /* Print out the command prompt, optionally ask where cursor is */
1994         parse_and_put_prompt(prompt);
1995         ask_terminal();
1996
1997         read_key_buffer[0] = 0;
1998         while (1) {
1999                 /*
2000                  * The emacs and vi modes share much of the code in the big
2001                  * command loop.  Commands entered when in vi's command mode
2002                  * (aka "escape mode") get an extra bit added to distinguish
2003                  * them - this keeps them from being self-inserted. This
2004                  * clutters the big switch a bit, but keeps all the code
2005                  * in one place.
2006                  */
2007                 enum {
2008                         VI_CMDMODE_BIT = 0x40000000,
2009                         /* 0x80000000 bit flags KEYCODE_xxx */
2010                 };
2011                 int32_t ic, ic_raw;
2012
2013                 fflush_all();
2014                 ic = ic_raw = lineedit_read_key(read_key_buffer);
2015
2016 #if ENABLE_FEATURE_EDITING_VI
2017                 newdelflag = 1;
2018                 if (vi_cmdmode) {
2019                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2020                          * change ic if it contains one of them: */
2021                         ic |= VI_CMDMODE_BIT;
2022                 }
2023 #endif
2024
2025                 switch (ic) {
2026                 case '\n':
2027                 case '\r':
2028                 vi_case('\n'|VI_CMDMODE_BIT:)
2029                 vi_case('\r'|VI_CMDMODE_BIT:)
2030                         /* Enter */
2031                         goto_new_line();
2032                         break_out = 1;
2033                         break;
2034                 case CTRL('A'):
2035                 vi_case('0'|VI_CMDMODE_BIT:)
2036                         /* Control-a -- Beginning of line */
2037                         input_backward(cursor);
2038                         break;
2039                 case CTRL('B'):
2040                 vi_case('h'|VI_CMDMODE_BIT:)
2041                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2042                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2043                         input_backward(1); /* Move back one character */
2044                         break;
2045                 case CTRL('E'):
2046                 vi_case('$'|VI_CMDMODE_BIT:)
2047                         /* Control-e -- End of line */
2048                         put_till_end_and_adv_cursor();
2049                         break;
2050                 case CTRL('F'):
2051                 vi_case('l'|VI_CMDMODE_BIT:)
2052                 vi_case(' '|VI_CMDMODE_BIT:)
2053                         input_forward(); /* Move forward one character */
2054                         break;
2055                 case '\b':   /* ^H */
2056                 case '\x7f': /* DEL */
2057                         if (!isrtl_str())
2058                                 input_backspace();
2059                         else
2060                                 input_delete(0);
2061                         break;
2062                 case KEYCODE_DELETE:
2063                         if (!isrtl_str())
2064                                 input_delete(0);
2065                         else
2066                                 input_backspace();
2067                         break;
2068 #if ENABLE_FEATURE_TAB_COMPLETION
2069                 case '\t':
2070                         input_tab(&lastWasTab);
2071                         break;
2072 #endif
2073                 case CTRL('K'):
2074                         /* Control-k -- clear to end of line */
2075                         command_ps[cursor] = BB_NUL;
2076                         command_len = cursor;
2077                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2078                         break;
2079                 case CTRL('L'):
2080                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2081                         /* Control-l -- clear screen */
2082                         printf("\033[H"); /* cursor to top,left */
2083                         redraw(0, command_len - cursor);
2084                         break;
2085 #if MAX_HISTORY > 0
2086                 case CTRL('N'):
2087                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2088                 vi_case('j'|VI_CMDMODE_BIT:)
2089                         /* Control-n -- Get next command in history */
2090                         if (get_next_history())
2091                                 goto rewrite_line;
2092                         break;
2093                 case CTRL('P'):
2094                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2095                 vi_case('k'|VI_CMDMODE_BIT:)
2096                         /* Control-p -- Get previous command from history */
2097                         if (get_previous_history())
2098                                 goto rewrite_line;
2099                         break;
2100 #endif
2101                 case CTRL('U'):
2102                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2103                         /* Control-U -- Clear line before cursor */
2104                         if (cursor) {
2105                                 command_len -= cursor;
2106                                 memmove(command_ps, command_ps + cursor,
2107                                         (command_len + 1) * sizeof(command_ps[0]));
2108                                 redraw(cmdedit_y, command_len);
2109                         }
2110                         break;
2111                 case CTRL('W'):
2112                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2113                         /* Control-W -- Remove the last word */
2114                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2115                                 input_backspace();
2116                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2117                                 input_backspace();
2118                         break;
2119
2120 #if ENABLE_FEATURE_EDITING_VI
2121                 case 'i'|VI_CMDMODE_BIT:
2122                         vi_cmdmode = 0;
2123                         break;
2124                 case 'I'|VI_CMDMODE_BIT:
2125                         input_backward(cursor);
2126                         vi_cmdmode = 0;
2127                         break;
2128                 case 'a'|VI_CMDMODE_BIT:
2129                         input_forward();
2130                         vi_cmdmode = 0;
2131                         break;
2132                 case 'A'|VI_CMDMODE_BIT:
2133                         put_till_end_and_adv_cursor();
2134                         vi_cmdmode = 0;
2135                         break;
2136                 case 'x'|VI_CMDMODE_BIT:
2137                         input_delete(1);
2138                         break;
2139                 case 'X'|VI_CMDMODE_BIT:
2140                         if (cursor > 0) {
2141                                 input_backward(1);
2142                                 input_delete(1);
2143                         }
2144                         break;
2145                 case 'W'|VI_CMDMODE_BIT:
2146                         vi_Word_motion(1);
2147                         break;
2148                 case 'w'|VI_CMDMODE_BIT:
2149                         vi_word_motion(1);
2150                         break;
2151                 case 'E'|VI_CMDMODE_BIT:
2152                         vi_End_motion();
2153                         break;
2154                 case 'e'|VI_CMDMODE_BIT:
2155                         vi_end_motion();
2156                         break;
2157                 case 'B'|VI_CMDMODE_BIT:
2158                         vi_Back_motion();
2159                         break;
2160                 case 'b'|VI_CMDMODE_BIT:
2161                         vi_back_motion();
2162                         break;
2163                 case 'C'|VI_CMDMODE_BIT:
2164                         vi_cmdmode = 0;
2165                         /* fall through */
2166                 case 'D'|VI_CMDMODE_BIT:
2167                         goto clear_to_eol;
2168
2169                 case 'c'|VI_CMDMODE_BIT:
2170                         vi_cmdmode = 0;
2171                         /* fall through */
2172                 case 'd'|VI_CMDMODE_BIT: {
2173                         int nc, sc;
2174
2175                         ic = lineedit_read_key(read_key_buffer);
2176                         if (errno) /* error */
2177                                 goto prepare_to_die;
2178                         if (ic == ic_raw) { /* "cc", "dd" */
2179                                 input_backward(cursor);
2180                                 goto clear_to_eol;
2181                                 break;
2182                         }
2183
2184                         sc = cursor;
2185                         switch (ic) {
2186                         case 'w':
2187                         case 'W':
2188                         case 'e':
2189                         case 'E':
2190                                 switch (ic) {
2191                                 case 'w':   /* "dw", "cw" */
2192                                         vi_word_motion(vi_cmdmode);
2193                                         break;
2194                                 case 'W':   /* 'dW', 'cW' */
2195                                         vi_Word_motion(vi_cmdmode);
2196                                         break;
2197                                 case 'e':   /* 'de', 'ce' */
2198                                         vi_end_motion();
2199                                         input_forward();
2200                                         break;
2201                                 case 'E':   /* 'dE', 'cE' */
2202                                         vi_End_motion();
2203                                         input_forward();
2204                                         break;
2205                                 }
2206                                 nc = cursor;
2207                                 input_backward(cursor - sc);
2208                                 while (nc-- > cursor)
2209                                         input_delete(1);
2210                                 break;
2211                         case 'b':  /* "db", "cb" */
2212                         case 'B':  /* implemented as B */
2213                                 if (ic == 'b')
2214                                         vi_back_motion();
2215                                 else
2216                                         vi_Back_motion();
2217                                 while (sc-- > cursor)
2218                                         input_delete(1);
2219                                 break;
2220                         case ' ':  /* "d ", "c " */
2221                                 input_delete(1);
2222                                 break;
2223                         case '$':  /* "d$", "c$" */
2224  clear_to_eol:
2225                                 while (cursor < command_len)
2226                                         input_delete(1);
2227                                 break;
2228                         }
2229                         break;
2230                 }
2231                 case 'p'|VI_CMDMODE_BIT:
2232                         input_forward();
2233                         /* fallthrough */
2234                 case 'P'|VI_CMDMODE_BIT:
2235                         put();
2236                         break;
2237                 case 'r'|VI_CMDMODE_BIT:
2238 //FIXME: unicode case?
2239                         ic = lineedit_read_key(read_key_buffer);
2240                         if (errno) /* error */
2241                                 goto prepare_to_die;
2242                         if (ic < ' ' || ic > 255) {
2243                                 beep();
2244                         } else {
2245                                 command_ps[cursor] = ic;
2246                                 bb_putchar(ic);
2247                                 bb_putchar('\b');
2248                         }
2249                         break;
2250                 case '\x1b': /* ESC */
2251                         if (state->flags & VI_MODE) {
2252                                 /* insert mode --> command mode */
2253                                 vi_cmdmode = 1;
2254                                 input_backward(1);
2255                         }
2256                         break;
2257 #endif /* FEATURE_COMMAND_EDITING_VI */
2258
2259 #if MAX_HISTORY > 0
2260                 case KEYCODE_UP:
2261                         if (get_previous_history())
2262                                 goto rewrite_line;
2263                         beep();
2264                         break;
2265                 case KEYCODE_DOWN:
2266                         if (!get_next_history())
2267                                 break;
2268  rewrite_line:
2269                         /* Rewrite the line with the selected history item */
2270                         /* change command */
2271                         command_len = load_string(state->history[state->cur_history] ?
2272                                         state->history[state->cur_history] : "", maxsize);
2273                         /* redraw and go to eol (bol, in vi) */
2274                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2275                         break;
2276 #endif
2277                 case KEYCODE_RIGHT:
2278                         input_forward();
2279                         break;
2280                 case KEYCODE_LEFT:
2281                         input_backward(1);
2282                         break;
2283                 case KEYCODE_CTRL_LEFT:
2284                         ctrl_left();
2285                         break;
2286                 case KEYCODE_CTRL_RIGHT:
2287                         ctrl_right();
2288                         break;
2289                 case KEYCODE_HOME:
2290                         input_backward(cursor);
2291                         break;
2292                 case KEYCODE_END:
2293                         put_till_end_and_adv_cursor();
2294                         break;
2295
2296                 default:
2297                         if (initial_settings.c_cc[VINTR] != 0
2298                          && ic_raw == initial_settings.c_cc[VINTR]
2299                         ) {
2300                                 /* Ctrl-C (usually) - stop gathering input */
2301                                 goto_new_line();
2302                                 command_len = 0;
2303                                 break_out = -1; /* "do not append '\n'" */
2304                                 break;
2305                         }
2306                         if (initial_settings.c_cc[VEOF] != 0
2307                          && ic_raw == initial_settings.c_cc[VEOF]
2308                         ) {
2309                                 /* Ctrl-D (usually) - delete one character,
2310                                  * or exit if len=0 and no chars to delete */
2311                                 if (command_len == 0) {
2312                                         errno = 0;
2313 #if ENABLE_FEATURE_EDITING_VI
2314  prepare_to_die:
2315 #endif
2316                                         break_out = command_len = -1;
2317                                         break;
2318                                 }
2319                                 input_delete(0);
2320                                 break;
2321                         }
2322 //                      /* Control-V -- force insert of next char */
2323 //                      if (c == CTRL('V')) {
2324 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2325 //                                      goto prepare_to_die;
2326 //                              if (c == 0) {
2327 //                                      beep();
2328 //                                      break;
2329 //                              }
2330 //                      }
2331                         if (ic < ' '
2332                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2333                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2334                         ) {
2335                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2336                                  * and vi mode ignores unexpected chars.
2337                                  * Otherwise, we are here if ic is a
2338                                  * control char or an unhandled ESC sequence,
2339                                  * which is also ignored.
2340                                  */
2341                                 break;
2342                         }
2343                         if ((int)command_len >= (maxsize - 2)) {
2344                                 /* Not enough space for the char and EOL */
2345                                 break;
2346                         }
2347
2348                         command_len++;
2349                         if (cursor == (command_len - 1)) {
2350                                 /* We are at the end, append */
2351                                 command_ps[cursor] = ic;
2352                                 command_ps[cursor + 1] = BB_NUL;
2353                                 put_cur_glyph_and_inc_cursor();
2354                                 if (unicode_bidi_isrtl(ic))
2355                                         input_backward(1);
2356                         } else {
2357                                 /* In the middle, insert */
2358                                 int sc = cursor;
2359
2360                                 memmove(command_ps + sc + 1, command_ps + sc,
2361                                         (command_len - sc) * sizeof(command_ps[0]));
2362                                 command_ps[sc] = ic;
2363                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2364                                 if (!isrtl_str())
2365                                         sc++; /* no */
2366                                 put_till_end_and_adv_cursor();
2367                                 /* to prev x pos + 1 */
2368                                 input_backward(cursor - sc);
2369                         }
2370                         break;
2371                 } /* switch (ic) */
2372
2373                 if (break_out)
2374                         break;
2375
2376 #if ENABLE_FEATURE_TAB_COMPLETION
2377                 if (ic_raw != '\t')
2378                         lastWasTab = 0;
2379 #endif
2380         } /* while (1) */
2381
2382 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2383         if (S.sent_ESC_br6n) {
2384                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2385                  * We sent "ESC [ 6 n", but got '\n' first, and
2386                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2387                  * It's bad already and not much can be done with it
2388                  * (it _will_ be visible for the next process to read stdin),
2389                  * but without this delay it even shows up on the screen
2390                  * as garbage because we restore echo settings with tcsetattr
2391                  * before it comes in. UGLY!
2392                  */
2393                 usleep(20*1000);
2394         }
2395 #endif
2396
2397 /* End of bug-catching "command_must_not_be_used" trick */
2398 #undef command
2399
2400 #if ENABLE_UNICODE_SUPPORT
2401         command[0] = '\0';
2402         if (command_len > 0)
2403                 command_len = save_string(command, maxsize - 1);
2404         free(command_ps);
2405 #endif
2406
2407         if (command_len > 0)
2408                 remember_in_history(command);
2409
2410         if (break_out > 0) {
2411                 command[command_len++] = '\n';
2412                 command[command_len] = '\0';
2413         }
2414
2415 #if ENABLE_FEATURE_TAB_COMPLETION
2416         free_tab_completion_data();
2417 #endif
2418
2419         /* restore initial_settings */
2420         tcsetattr_stdin_TCSANOW(&initial_settings);
2421         /* restore SIGWINCH handler */
2422         signal(SIGWINCH, previous_SIGWINCH_handler);
2423         fflush_all();
2424
2425         len = command_len;
2426         DEINIT_S();
2427
2428         return len; /* can't return command_len, DEINIT_S() destroys it */
2429 }
2430
2431 #else  /* !FEATURE_EDITING */
2432
2433 #undef read_line_input
2434 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2435 {
2436         fputs(prompt, stdout);
2437         fflush_all();
2438         fgets(command, maxsize, stdin);
2439         return strlen(command);
2440 }
2441
2442 #endif  /* !FEATURE_EDITING */
2443
2444
2445 /*
2446  * Testing
2447  */
2448
2449 #ifdef TEST
2450
2451 #include <locale.h>
2452
2453 const char *applet_name = "debug stuff usage";
2454
2455 int main(int argc, char **argv)
2456 {
2457         char buff[MAX_LINELEN];
2458         char *prompt =
2459 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2460                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2461                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2462                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2463 #else
2464                 "% ";
2465 #endif
2466
2467         while (1) {
2468                 int l;
2469                 l = read_line_input(prompt, buff);
2470                 if (l <= 0 || buff[l-1] != '\n')
2471                         break;
2472                 buff[l-1] = '\0';
2473                 printf("*** read_line_input() returned line =%s=\n", buff);
2474         }
2475         printf("*** read_line_input() detect ^D\n");
2476         return 0;
2477 }
2478
2479 #endif  /* TEST */