libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Termios command line History and 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_FEATURE_GETUSERNAME_AND_HOMEDIR \
  57         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  58 #define IF_FEATURE_GETUSERNAME_AND_HOMEDIR(...)
  59 #if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
  60 #undef IF_FEATURE_GETUSERNAME_AND_HOMEDIR
  61 #define IF_FEATURE_GETUSERNAME_AND_HOMEDIR(...) __VA_ARGS__
  62 #endif
  63
  64
  65 #define SEQ_CLEAR_TILL_END_OF_SCREEN "\033[J"
  66 //#define SEQ_CLEAR_TILL_END_OF_LINE   "\033[K"
  67
  68
  69 #undef CHAR_T
  70 #if ENABLE_UNICODE_SUPPORT
  71 # define BB_NUL ((wchar_t)0)
  72 # define CHAR_T wchar_t
  73 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  74 # if ENABLE_FEATURE_EDITING_VI
  75 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  76 # endif
  77 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  78 # undef isspace
  79 # undef isalnum
  80 # undef ispunct
  81 # undef isprint
  82 # define isspace isspace_must_not_be_used
  83 # define isalnum isalnum_must_not_be_used
  84 # define ispunct ispunct_must_not_be_used
  85 # define isprint isprint_must_not_be_used
  86 #else
  87 # define BB_NUL '\0'
  88 # define CHAR_T char
  89 # define BB_isspace(c) isspace(c)
  90 # define BB_isalnum(c) isalnum(c)
  91 # define BB_ispunct(c) ispunct(c)
  92 #endif
  93
  94
  95 # if ENABLE_UNICODE_PRESERVE_BROKEN
  96 #  define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
  97 #  define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
  98 # else
  99 #  define unicode_is_raw_byte(wc)     0
 100 # endif
 101
 102
 103 enum {
 104         /* We use int16_t for positions, need to limit line len */
 105         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 106                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 107                       : 0x7ff0
 108 };
 109
 110 #if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
 111 static const char null_str[] ALIGN1 = "";
 112 #endif
 113
 114 /* We try to minimize both static and stack usage. */
 115 struct lineedit_statics {
 116         line_input_t *state;
 117
 118         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 119         sighandler_t previous_SIGWINCH_handler;
 120
 121         unsigned cmdedit_x;        /* real x (col) terminal position */
 122         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 123         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 124
 125         unsigned cursor;
 126         int command_len; /* must be signed */
 127         /* signed maxsize: we want x in "if (x > S.maxsize)"
 128          * to _not_ be promoted to unsigned */
 129         int maxsize;
 130         CHAR_T *command_ps;
 131
 132         const char *cmdedit_prompt;
 133 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 134         int num_ok_lines; /* = 1; */
 135 #endif
 136
 137 #if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
 138         char *user_buf;
 139         char *home_pwd_buf; /* = (char*)null_str; */
 140 #endif
 141
 142 #if ENABLE_FEATURE_TAB_COMPLETION
 143         char **matches;
 144         unsigned num_matches;
 145 #endif
 146
 147 #if ENABLE_FEATURE_EDITING_VI
 148 #define DELBUFSIZ 128
 149         CHAR_T *delptr;
 150         smallint newdelflag;     /* whether delbuf should be reused yet */
 151         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 152 #endif
 153 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 154         smallint sent_ESC_br6n;
 155 #endif
 156
 157         /* Formerly these were big buffers on stack: */
 158 #if ENABLE_FEATURE_TAB_COMPLETION
 159         char exe_n_cwd_tab_completion__dirbuf[MAX_LINELEN];
 160         char input_tab__matchBuf[MAX_LINELEN];
 161         int16_t find_match__int_buf[MAX_LINELEN + 1]; /* need to have 9 bits at least */
 162         int16_t find_match__pos_buf[MAX_LINELEN + 1];
 163 #endif
 164 };
 165
 166 /* See lineedit_ptr_hack.c */
 167 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 168
 169 #define S (*lineedit_ptr_to_statics)
 170 #define state            (S.state           )
 171 #define cmdedit_termw    (S.cmdedit_termw   )
 172 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 173 #define cmdedit_x        (S.cmdedit_x       )
 174 #define cmdedit_y        (S.cmdedit_y       )
 175 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 176 #define cursor           (S.cursor          )
 177 #define command_len      (S.command_len     )
 178 #define command_ps       (S.command_ps      )
 179 #define cmdedit_prompt   (S.cmdedit_prompt  )
 180 #define num_ok_lines     (S.num_ok_lines    )
 181 #define user_buf         (S.user_buf        )
 182 #define home_pwd_buf     (S.home_pwd_buf    )
 183 #define matches          (S.matches         )
 184 #define num_matches      (S.num_matches     )
 185 #define delptr           (S.delptr          )
 186 #define newdelflag       (S.newdelflag      )
 187 #define delbuf           (S.delbuf          )
 188
 189 #define INIT_S() do { \
 190         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 191         barrier(); \
 192         cmdedit_termw = 80; \
 193         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
 194         IF_FEATURE_GETUSERNAME_AND_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 195 } while (0)
 196 static void deinit_S(void)
 197 {
 198 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 199         /* This one is allocated only if FANCY_PROMPT is on
 200          * (otherwise it points to verbatim prompt (NOT malloced) */
 201         free((char*)cmdedit_prompt);
 202 #endif
 203 #if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
 204         free(user_buf);
 205         if (home_pwd_buf != null_str)
 206                 free(home_pwd_buf);
 207 #endif
 208         free(lineedit_ptr_to_statics);
 209 }
 210 #define DEINIT_S() deinit_S()
 211
 212
 213 #if ENABLE_UNICODE_SUPPORT
 214 static size_t load_string(const char *src, int maxsize)
 215 {
 216         ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
 217         if (len < 0)
 218                 len = 0;
 219         command_ps[len] = 0;
 220         return len;
 221 }
 222 static unsigned save_string(char *dst, unsigned maxsize)
 223 {
 224 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 225         ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 226         if (len < 0)
 227                 len = 0;
 228         dst[len] = '\0';
 229         return len;
 230 # else
 231         unsigned dstpos = 0;
 232         unsigned srcpos = 0;
 233
 234         maxsize--;
 235         while (dstpos < maxsize) {
 236                 wchar_t wc;
 237                 int n = srcpos;
 238                 while ((wc = command_ps[srcpos]) != 0
 239                     && !unicode_is_raw_byte(wc)
 240                 ) {
 241                         srcpos++;
 242                 }
 243                 command_ps[srcpos] = 0;
 244                 n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 245                 if (n < 0) /* should not happen */
 246                         break;
 247                 dstpos += n;
 248                 if (wc == 0) /* usually is */
 249                         break;
 250                 /* We do have invalid byte here! */
 251                 command_ps[srcpos] = wc; /* restore it */
 252                 srcpos++;
 253                 if (dstpos == maxsize)
 254                         break;
 255                 dst[dstpos++] = (char) wc;
 256         }
 257         dst[dstpos] = '\0';
 258         return dstpos;
 259 # endif
 260 }
 261 /* I thought just fputwc(c, stdout) would work. But no... */
 262 static void BB_PUTCHAR(wchar_t c)
 263 {
 264         char buf[MB_CUR_MAX + 1];
 265         mbstate_t mbst = { 0 };
 266         ssize_t len;
 267
 268         len = wcrtomb(buf, c, &mbst);
 269         if (len > 0) {
 270                 buf[len] = '\0';
 271                 fputs(buf, stdout);
 272         }
 273 }
 274 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 275 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 276 # else
 277 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 278 #  define adjust_width_and_validate_wc(width_adj, wc) \
 279         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 280 # endif
 281 {
 282         int w = 1;
 283
 284         if (unicode_status == UNICODE_ON) {
 285                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 286                         /* note: also true for unicode_is_raw_byte(wc) */
 287                         goto subst;
 288                 }
 289                 w = wcwidth(wc);
 290                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 291                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 292                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 293                 ) {
 294  subst:
 295                         w = 1;
 296                         wc = CONFIG_SUBST_WCHAR;
 297                 }
 298         }
 299
 300 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 301         *width_adj += w;
 302 #endif
 303         return wc;
 304 }
 305 #else /* !UNICODE */
 306 static size_t load_string(const char *src, int maxsize)
 307 {
 308         safe_strncpy(command_ps, src, maxsize);
 309         return strlen(command_ps);
 310 }
 311 # if ENABLE_FEATURE_TAB_COMPLETION
 312 static void save_string(char *dst, unsigned maxsize)
 313 {
 314         safe_strncpy(dst, command_ps, maxsize);
 315 }
 316 # endif
 317 # define BB_PUTCHAR(c) bb_putchar(c)
 318 /* Should never be called: */
 319 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 320 #endif
 321
 322
 323 /* Put 'command_ps[cursor]', cursor++.
 324  * Advance cursor on screen. If we reached right margin, scroll text up
 325  * and remove terminal margin effect by printing 'next_char' */
 326 #define HACK_FOR_WRONG_WIDTH 1
 327 static void put_cur_glyph_and_inc_cursor(void)
 328 {
 329         CHAR_T c = command_ps[cursor];
 330         unsigned width = 0;
 331         int ofs_to_right;
 332
 333         if (c == BB_NUL) {
 334                 /* erase character after end of input string */
 335                 c = ' ';
 336         } else {
 337                 /* advance cursor only if we aren't at the end yet */
 338                 cursor++;
 339                 if (unicode_status == UNICODE_ON) {
 340                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 341                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 342                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 343                 } else {
 344                         cmdedit_x++;
 345                 }
 346         }
 347
 348         ofs_to_right = cmdedit_x - cmdedit_termw;
 349         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 350                 /* c fits on this line */
 351                 BB_PUTCHAR(c);
 352         }
 353
 354         if (ofs_to_right >= 0) {
 355                 /* we go to the next line */
 356 #if HACK_FOR_WRONG_WIDTH
 357                 /* This works better if our idea of term width is wrong
 358                  * and it is actually wider (often happens on serial lines).
 359                  * Printing CR,LF *forces* cursor to next line.
 360                  * OTOH if terminal width is correct AND terminal does NOT
 361                  * have automargin (IOW: it is moving cursor to next line
 362                  * by itself (which is wrong for VT-10x terminals)),
 363                  * this will break things: there will be one extra empty line */
 364                 puts("\r"); /* + implicit '\n' */
 365 #else
 366                 /* VT-10x terminals don't wrap cursor to next line when last char
 367                  * on the line is printed - cursor stays "over" this char.
 368                  * Need to print _next_ char too (first one to appear on next line)
 369                  * to make cursor move down to next line.
 370                  */
 371                 /* Works ok only if cmdedit_termw is correct. */
 372                 c = command_ps[cursor];
 373                 if (c == BB_NUL)
 374                         c = ' ';
 375                 BB_PUTCHAR(c);
 376                 bb_putchar('\b');
 377 #endif
 378                 cmdedit_y++;
 379                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 380                         width = 0;
 381                 } else { /* ofs_to_right > 0 */
 382                         /* wide char c didn't fit on prev line */
 383                         BB_PUTCHAR(c);
 384                 }
 385                 cmdedit_x = width;
 386         }
 387 }
 388
 389 /* Move to end of line (by printing all chars till the end) */
 390 static void put_till_end_and_adv_cursor(void)
 391 {
 392         while (cursor < command_len)
 393                 put_cur_glyph_and_inc_cursor();
 394 }
 395
 396 /* Go to the next line */
 397 static void goto_new_line(void)
 398 {
 399         put_till_end_and_adv_cursor();
 400         if (cmdedit_x)
 401                 bb_putchar('\n');
 402 }
 403
 404
 405 static void out1str(const char *s)
 406 {
 407         if (s)
 408                 fputs(s, stdout);
 409 }
 410
 411 static void beep(void)
 412 {
 413         bb_putchar('\007');
 414 }
 415
 416 /* Move back one character */
 417 /* (optimized for slow terminals) */
 418 static void input_backward(unsigned num)
 419 {
 420         int count_y;
 421
 422         if (num > cursor)
 423                 num = cursor;
 424         if (num == 0)
 425                 return;
 426         cursor -= num;
 427
 428         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 429          && unicode_status == UNICODE_ON
 430         ) {
 431                 /* correct NUM to be equal to _screen_ width */
 432                 int n = num;
 433                 num = 0;
 434                 while (--n >= 0)
 435                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 436                 if (num == 0)
 437                         return;
 438         }
 439
 440         if (cmdedit_x >= num) {
 441                 cmdedit_x -= num;
 442                 if (num <= 4) {
 443                         /* This is longer by 5 bytes on x86.
 444                          * Also gets miscompiled for ARM users
 445                          * (busybox.net/bugs/view.php?id=2274).
 446                          * printf(("\b\b\b\b" + 4) - num);
 447                          * return;
 448                          */
 449                         do {
 450                                 bb_putchar('\b');
 451                         } while (--num);
 452                         return;
 453                 }
 454                 printf("\033[%uD", num);
 455                 return;
 456         }
 457
 458         /* Need to go one or more lines up */
 459 //FIXME: this does not work correctly if prev line has one "unfilled" screen position
 460 //caused by wide unicode char not fitting in that one screen position.
 461         num -= cmdedit_x;
 462         {
 463                 unsigned w = cmdedit_termw; /* volatile var */
 464                 count_y = 1 + (num / w);
 465                 cmdedit_y -= count_y;
 466                 cmdedit_x = w * count_y - num;
 467         }
 468         /* go to 1st column; go up; go to correct column */
 469         printf("\r" "\033[%uA" "\033[%uC", count_y, cmdedit_x);
 470 }
 471
 472 static void put_prompt(void)
 473 {
 474         unsigned w;
 475
 476         out1str(cmdedit_prompt);
 477         fflush_all();
 478         cursor = 0;
 479         w = cmdedit_termw; /* read volatile var once */
 480         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 481         cmdedit_x = cmdedit_prmt_len % w;
 482 }
 483
 484 /* draw prompt, editor line, and clear tail */
 485 static void redraw(int y, int back_cursor)
 486 {
 487         if (y > 0)  /* up to start y */
 488                 printf("\033[%uA", y);
 489         bb_putchar('\r');
 490         put_prompt();
 491         put_till_end_and_adv_cursor();
 492         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 493         input_backward(back_cursor);
 494 }
 495
 496 /* Delete the char in front of the cursor, optionally saving it
 497  * for later putback */
 498 #if !ENABLE_FEATURE_EDITING_VI
 499 static void input_delete(void)
 500 #define input_delete(save) input_delete()
 501 #else
 502 static void input_delete(int save)
 503 #endif
 504 {
 505         int j = cursor;
 506
 507         if (j == (int)command_len)
 508                 return;
 509
 510 #if ENABLE_FEATURE_EDITING_VI
 511         if (save) {
 512                 if (newdelflag) {
 513                         delptr = delbuf;
 514                         newdelflag = 0;
 515                 }
 516                 if ((delptr - delbuf) < DELBUFSIZ)
 517                         *delptr++ = command_ps[j];
 518         }
 519 #endif
 520
 521         memmove(command_ps + j, command_ps + j + 1,
 522                         /* (command_len + 1 [because of NUL]) - (j + 1)
 523                          * simplified into (command_len - j) */
 524                         (command_len - j) * sizeof(command_ps[0]));
 525         command_len--;
 526         put_till_end_and_adv_cursor();
 527         /* Last char is still visible, erase it (and more) */
 528         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 529         input_backward(cursor - j);     /* back to old pos cursor */
 530 }
 531
 532 #if ENABLE_FEATURE_EDITING_VI
 533 static void put(void)
 534 {
 535         int ocursor;
 536         int j = delptr - delbuf;
 537
 538         if (j == 0)
 539                 return;
 540         ocursor = cursor;
 541         /* open hole and then fill it */
 542         memmove(command_ps + cursor + j, command_ps + cursor,
 543                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 544         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 545         command_len += j;
 546         put_till_end_and_adv_cursor();
 547         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 548 }
 549 #endif
 550
 551 /* Delete the char in back of the cursor */
 552 static void input_backspace(void)
 553 {
 554         if (cursor > 0) {
 555                 input_backward(1);
 556                 input_delete(0);
 557         }
 558 }
 559
 560 /* Move forward one character */
 561 static void input_forward(void)
 562 {
 563         if (cursor < command_len)
 564                 put_cur_glyph_and_inc_cursor();
 565 }
 566
 567 #if ENABLE_FEATURE_TAB_COMPLETION
 568
 569 static void free_tab_completion_data(void)
 570 {
 571         if (matches) {
 572                 while (num_matches)
 573                         free(matches[--num_matches]);
 574                 free(matches);
 575                 matches = NULL;
 576         }
 577 }
 578
 579 static void add_match(char *matched)
 580 {
 581         matches = xrealloc_vector(matches, 4, num_matches);
 582         matches[num_matches] = matched;
 583         num_matches++;
 584 }
 585
 586 #if ENABLE_FEATURE_USERNAME_COMPLETION
 587 static void username_tab_completion(char *ud, char *with_shash_flg)
 588 {
 589         struct passwd *entry;
 590         int userlen;
 591
 592         ud++;                           /* ~user/... to user/... */
 593         userlen = strlen(ud);
 594
 595         if (with_shash_flg) {           /* "~/..." or "~user/..." */
 596                 char *sav_ud = ud - 1;
 597                 char *home = NULL;
 598
 599                 if (*ud == '/') {       /* "~/..."     */
 600                         home = home_pwd_buf;
 601                 } else {
 602                         /* "~user/..." */
 603                         char *temp;
 604                         temp = strchr(ud, '/');
 605                         *temp = '\0';           /* ~user\0 */
 606                         entry = getpwnam(ud);
 607                         *temp = '/';            /* restore ~user/... */
 608                         ud = temp;
 609                         if (entry)
 610                                 home = entry->pw_dir;
 611                 }
 612                 if (home) {
 613                         if ((userlen + strlen(home) + 1) < MAX_LINELEN) {
 614                                 /* /home/user/... */
 615                                 sprintf(sav_ud, "%s%s", home, ud);
 616                         }
 617                 }
 618         } else {
 619                 /* "~[^/]*" */
 620                 /* Using _r function to avoid pulling in static buffers */
 621                 char line_buff[256];
 622                 struct passwd pwd;
 623                 struct passwd *result;
 624
 625                 setpwent();
 626                 while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
 627                         /* Null usernames should result in all users as possible completions. */
 628                         if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
 629                                 add_match(xasprintf("~%s/", pwd.pw_name));
 630                         }
 631                 }
 632                 endpwent();
 633         }
 634 }
 635 #endif  /* FEATURE_COMMAND_USERNAME_COMPLETION */
 636
 637 enum {
 638         FIND_EXE_ONLY = 0,
 639         FIND_DIR_ONLY = 1,
 640         FIND_FILE_ONLY = 2,
 641 };
 642
 643 static int path_parse(char ***p, int flags)
 644 {
 645         int npth;
 646         const char *pth;
 647         char *tmp;
 648         char **res;
 649
 650         /* if not setenv PATH variable, to search cur dir "." */
 651         if (flags != FIND_EXE_ONLY)
 652                 return 1;
 653
 654         if (state->flags & WITH_PATH_LOOKUP)
 655                 pth = state->path_lookup;
 656         else
 657                 pth = getenv("PATH");
 658         /* PATH=<empty> or PATH=:<empty> */
 659         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 660                 return 1;
 661
 662         tmp = (char*)pth;
 663         npth = 1; /* path component count */
 664         while (1) {
 665                 tmp = strchr(tmp, ':');
 666                 if (!tmp)
 667                         break;
 668                 if (*++tmp == '\0')
 669                         break;  /* :<empty> */
 670                 npth++;
 671         }
 672
 673         res = xmalloc(npth * sizeof(char*));
 674         res[0] = tmp = xstrdup(pth);
 675         npth = 1;
 676         while (1) {
 677                 tmp = strchr(tmp, ':');
 678                 if (!tmp)
 679                         break;
 680                 *tmp++ = '\0'; /* ':' -> '\0' */
 681                 if (*tmp == '\0')
 682                         break; /* :<empty> */
 683                 res[npth++] = tmp;
 684         }
 685         *p = res;
 686         return npth;
 687 }
 688
 689 static void exe_n_cwd_tab_completion(char *command, int type)
 690 {
 691         DIR *dir;
 692         struct dirent *next;
 693         struct stat st;
 694         char *path1[1];
 695         char **paths = path1;
 696         int npaths;
 697         int i;
 698         char *found;
 699         char *pfind = strrchr(command, '/');
 700 /*      char dirbuf[MAX_LINELEN]; */
 701 #define dirbuf (S.exe_n_cwd_tab_completion__dirbuf)
 702
 703         npaths = 1;
 704         path1[0] = (char*)".";
 705
 706         if (pfind == NULL) {
 707                 /* no dir, if flags==EXE_ONLY - get paths, else "." */
 708                 npaths = path_parse(&paths, type);
 709                 pfind = command;
 710         } else {
 711                 /* dirbuf = ".../.../.../" */
 712                 safe_strncpy(dirbuf, command, (pfind - command) + 2);
 713 #if ENABLE_FEATURE_USERNAME_COMPLETION
 714                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 715                         username_tab_completion(dirbuf, dirbuf);
 716 #endif
 717                 paths[0] = dirbuf;
 718                 /* point to 'l' in "..../last_component" */
 719                 pfind++;
 720         }
 721
 722         for (i = 0; i < npaths; i++) {
 723                 dir = opendir(paths[i]);
 724                 if (!dir)
 725                         continue; /* don't print an error */
 726
 727                 while ((next = readdir(dir)) != NULL) {
 728                         int len1;
 729                         const char *str_found = next->d_name;
 730
 731                         /* matched? */
 732                         if (strncmp(str_found, pfind, strlen(pfind)))
 733                                 continue;
 734                         /* not see .name without .match */
 735                         if (*str_found == '.' && *pfind == '\0') {
 736                                 if (NOT_LONE_CHAR(paths[i], '/') || str_found[1])
 737                                         continue;
 738                                 str_found = ""; /* only "/" */
 739                         }
 740                         found = concat_path_file(paths[i], str_found);
 741                         /* hmm, remove in progress? */
 742                         /* NB: stat() first so that we see is it a directory;
 743                          * but if that fails, use lstat() so that
 744                          * we still match dangling links */
 745                         if (stat(found, &st) && lstat(found, &st))
 746                                 goto cont;
 747                         /* find with dirs? */
 748                         if (paths[i] != dirbuf)
 749                                 strcpy(found, next->d_name); /* only name */
 750
 751                         len1 = strlen(found);
 752                         found = xrealloc(found, len1 + 2);
 753                         found[len1] = '\0';
 754                         found[len1+1] = '\0';
 755
 756                         if (S_ISDIR(st.st_mode)) {
 757                                 /* name is a directory */
 758                                 if (found[len1-1] != '/') {
 759                                         found[len1] = '/';
 760                                 }
 761                         } else {
 762                                 /* not put found file if search only dirs for cd */
 763                                 if (type == FIND_DIR_ONLY)
 764                                         goto cont;
 765                         }
 766                         /* Add it to the list */
 767                         add_match(found);
 768                         continue;
 769  cont:
 770                         free(found);
 771                 }
 772                 closedir(dir);
 773         }
 774         if (paths != path1) {
 775                 free(paths[0]); /* allocated memory is only in first member */
 776                 free(paths);
 777         }
 778 #undef dirbuf
 779 }
 780
 781 /* QUOT is used on elements of int_buf[], which are bytes,
 782  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 783  */
 784 #define QUOT (UCHAR_MAX+1)
 785
 786 #define int_buf (S.find_match__int_buf)
 787 #define pos_buf (S.find_match__pos_buf)
 788 /* is must be <= in */
 789 static void collapse_pos(int is, int in)
 790 {
 791         memmove(int_buf+is, int_buf+in, (MAX_LINELEN+1-in)*sizeof(int_buf[0]));
 792         memmove(pos_buf+is, pos_buf+in, (MAX_LINELEN+1-in)*sizeof(pos_buf[0]));
 793 }
 794 static NOINLINE int find_match(char *matchBuf, int *len_with_quotes)
 795 {
 796         int i, j;
 797         int command_mode;
 798         int c, c2;
 799 /*      Were local, but it uses too much stack */
 800 /*      int16_t int_buf[MAX_LINELEN + 1]; */
 801 /*      int16_t pos_buf[MAX_LINELEN + 1]; */
 802
 803         /* set to integer dimension characters and own positions */
 804         for (i = 0;; i++) {
 805                 int_buf[i] = (unsigned char)matchBuf[i];
 806                 if (int_buf[i] == 0) {
 807                         pos_buf[i] = -1; /* end-fo-line indicator */
 808                         break;
 809                 }
 810                 pos_buf[i] = i;
 811         }
 812
 813         /* mask \+symbol and convert '\t' to ' ' */
 814         for (i = j = 0; matchBuf[i]; i++, j++) {
 815                 if (matchBuf[i] == '\\') {
 816                         collapse_pos(j, j + 1);
 817                         int_buf[j] |= QUOT;
 818                         i++;
 819                 }
 820         }
 821         /* mask "symbols" or 'symbols' */
 822         c2 = 0;
 823         for (i = 0; int_buf[i]; i++) {
 824                 c = int_buf[i];
 825                 if (c == '\'' || c == '"') {
 826                         if (c2 == 0)
 827                                 c2 = c;
 828                         else {
 829                                 if (c == c2)
 830                                         c2 = 0;
 831                                 else
 832                                         int_buf[i] |= QUOT;
 833                         }
 834                 } else if (c2 != 0 && c != '$')
 835                         int_buf[i] |= QUOT;
 836         }
 837
 838         /* skip commands with arguments if line has commands delimiters */
 839         /* ';' ';;' '&' '|' '&&' '||' but `>&' `<&' `>|' */
 840         for (i = 0; int_buf[i]; i++) {
 841                 c = int_buf[i];
 842                 c2 = int_buf[i + 1];
 843                 j = i ? int_buf[i - 1] : -1;
 844                 command_mode = 0;
 845                 if (c == ';' || c == '&' || c == '|') {
 846                         command_mode = 1 + (c == c2);
 847                         if (c == '&') {
 848                                 if (j == '>' || j == '<')
 849                                         command_mode = 0;
 850                         } else if (c == '|' && j == '>')
 851                                 command_mode = 0;
 852                 }
 853                 if (command_mode) {
 854                         collapse_pos(0, i + command_mode);
 855                         i = -1;  /* hack incremet */
 856                 }
 857         }
 858         /* collapse `command...` */
 859         for (i = 0; int_buf[i]; i++) {
 860                 if (int_buf[i] == '`') {
 861                         for (j = i + 1; int_buf[j]; j++)
 862                                 if (int_buf[j] == '`') {
 863                                         collapse_pos(i, j + 1);
 864                                         j = 0;
 865                                         break;
 866                                 }
 867                         if (j) {
 868                                 /* not found closing ` - command mode, collapse all previous */
 869                                 collapse_pos(0, i + 1);
 870                                 break;
 871                         } else
 872                                 i--;  /* hack incremet */
 873                 }
 874         }
 875
 876         /* collapse (command...(command...)...) or {command...{command...}...} */
 877         c = 0;  /* "recursive" level */
 878         c2 = 0;
 879         for (i = 0; int_buf[i]; i++) {
 880                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 881                         if (int_buf[i] == '(')
 882                                 c++;
 883                         else
 884                                 c2++;
 885                         collapse_pos(0, i + 1);
 886                         i = -1;  /* hack incremet */
 887                 }
 888         }
 889         for (i = 0; pos_buf[i] >= 0 && (c > 0 || c2 > 0); i++) {
 890                 if ((int_buf[i] == ')' && c > 0) || (int_buf[i] == '}' && c2 > 0)) {
 891                         if (int_buf[i] == ')')
 892                                 c--;
 893                         else
 894                                 c2--;
 895                         collapse_pos(0, i + 1);
 896                         i = -1;  /* hack incremet */
 897                 }
 898         }
 899
 900         /* skip first not quote space */
 901         for (i = 0; int_buf[i]; i++)
 902                 if (int_buf[i] != ' ')
 903                         break;
 904         if (i)
 905                 collapse_pos(0, i);
 906
 907         /* set find mode for completion */
 908         command_mode = FIND_EXE_ONLY;
 909         for (i = 0; int_buf[i]; i++) {
 910                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 911                         if (int_buf[i] == ' ' && command_mode == FIND_EXE_ONLY
 912                          && matchBuf[pos_buf[0]] == 'c'
 913                          && matchBuf[pos_buf[1]] == 'd'
 914                         ) {
 915                                 command_mode = FIND_DIR_ONLY;
 916                         } else {
 917                                 command_mode = FIND_FILE_ONLY;
 918                                 break;
 919                         }
 920                 }
 921         }
 922         for (i = 0; int_buf[i]; i++)
 923                 /* "strlen" */;
 924         /* find last word */
 925         for (--i; i >= 0; i--) {
 926                 c = int_buf[i];
 927                 if (c == ' ' || c == '<' || c == '>' || c == '|' || c == '&') {
 928                         collapse_pos(0, i + 1);
 929                         break;
 930                 }
 931         }
 932         /* skip first not quoted '\'' or '"' */
 933         for (i = 0; int_buf[i] == '\'' || int_buf[i] == '"'; i++)
 934                 /*skip*/;
 935         /* collapse quote or unquote // or /~ */
 936         while ((int_buf[i] & ~QUOT) == '/'
 937          && ((int_buf[i+1] & ~QUOT) == '/' || (int_buf[i+1] & ~QUOT) == '~')
 938         ) {
 939                 i++;
 940         }
 941
 942         /* set only match and destroy quotes */
 943         j = 0;
 944         for (c = 0; pos_buf[i] >= 0; i++) {
 945                 matchBuf[c++] = matchBuf[pos_buf[i]];
 946                 j = pos_buf[i] + 1;
 947         }
 948         matchBuf[c] = '\0';
 949         /* old length matchBuf with quotes symbols */
 950         *len_with_quotes = j ? j - pos_buf[0] : 0;
 951
 952         return command_mode;
 953 }
 954 #undef int_buf
 955 #undef pos_buf
 956
 957 /*
 958  * display by column (original idea from ls applet,
 959  * very optimized by me :)
 960  */
 961 static void showfiles(void)
 962 {
 963         int ncols, row;
 964         int column_width = 0;
 965         int nfiles = num_matches;
 966         int nrows = nfiles;
 967         int l;
 968
 969         /* find the longest file name - use that as the column width */
 970         for (row = 0; row < nrows; row++) {
 971                 l = unicode_strlen(matches[row]);
 972                 if (column_width < l)
 973                         column_width = l;
 974         }
 975         column_width += 2;              /* min space for columns */
 976         ncols = cmdedit_termw / column_width;
 977
 978         if (ncols > 1) {
 979                 nrows /= ncols;
 980                 if (nfiles % ncols)
 981                         nrows++;        /* round up fractionals */
 982         } else {
 983                 ncols = 1;
 984         }
 985         for (row = 0; row < nrows; row++) {
 986                 int n = row;
 987                 int nc;
 988
 989                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
 990                         printf("%s%-*s", matches[n],
 991                                 (int)(column_width - unicode_strlen(matches[n])), ""
 992                         );
 993                 }
 994                 puts(matches[n]);
 995         }
 996 }
 997
 998 static char *add_quote_for_spec_chars(char *found)
 999 {
1000         int l = 0;
1001         char *s = xzalloc((strlen(found) + 1) * 2);
1002
1003         while (*found) {
1004                 if (strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", *found))
1005                         s[l++] = '\\';
1006                 s[l++] = *found++;
1007         }
1008         /* s[l] = '\0'; - already is */
1009         return s;
1010 }
1011
1012 /* Do TAB completion */
1013 static void input_tab(smallint *lastWasTab)
1014 {
1015         if (!(state->flags & TAB_COMPLETION))
1016                 return;
1017
1018         if (!*lastWasTab) {
1019                 char *tmp, *tmp1;
1020                 size_t len_found;
1021 /*              char matchBuf[MAX_LINELEN]; */
1022 #define matchBuf (S.input_tab__matchBuf)
1023                 int find_type;
1024                 int recalc_pos;
1025 #if ENABLE_UNICODE_SUPPORT
1026                 /* cursor pos in command converted to multibyte form */
1027                 int cursor_mb;
1028 #endif
1029
1030                 *lastWasTab = TRUE;             /* flop trigger */
1031
1032                 /* Make a local copy of the string --
1033                  * up to the position of the cursor */
1034                 save_string(matchBuf, cursor + 1);
1035 #if ENABLE_UNICODE_SUPPORT
1036                 cursor_mb = strlen(matchBuf);
1037 #endif
1038                 tmp = matchBuf;
1039
1040                 find_type = find_match(matchBuf, &recalc_pos);
1041
1042                 /* Free up any memory already allocated */
1043                 free_tab_completion_data();
1044
1045 #if ENABLE_FEATURE_USERNAME_COMPLETION
1046                 /* If the word starts with `~' and there is no slash in the word,
1047                  * then try completing this word as a username. */
1048                 if (state->flags & USERNAME_COMPLETION)
1049                         if (matchBuf[0] == '~' && strchr(matchBuf, '/') == NULL)
1050                                 username_tab_completion(matchBuf, NULL);
1051 #endif
1052                 /* Try to match any executable in our path and everything
1053                  * in the current working directory */
1054                 if (!matches)
1055                         exe_n_cwd_tab_completion(matchBuf, find_type);
1056                 /* Sort, then remove any duplicates found */
1057                 if (matches) {
1058                         unsigned i;
1059                         int n = 0;
1060                         qsort_string_vector(matches, num_matches);
1061                         for (i = 0; i < num_matches - 1; ++i) {
1062                                 if (matches[i] && matches[i+1]) { /* paranoia */
1063                                         if (strcmp(matches[i], matches[i+1]) == 0) {
1064                                                 free(matches[i]);
1065                                                 matches[i] = NULL; /* paranoia */
1066                                         } else {
1067                                                 matches[n++] = matches[i];
1068                                         }
1069                                 }
1070                         }
1071                         matches[n] = matches[i];
1072                         num_matches = n + 1;
1073                 }
1074                 /* Did we find exactly one match? */
1075                 if (!matches || num_matches > 1) { /* no */
1076                         beep();
1077                         if (!matches)
1078                                 return;         /* not found */
1079                         /* find minimal match */
1080                         tmp1 = xstrdup(matches[0]);
1081                         for (tmp = tmp1; *tmp; tmp++) {
1082                                 for (len_found = 1; len_found < num_matches; len_found++) {
1083                                         if (matches[len_found][tmp - tmp1] != *tmp) {
1084                                                 *tmp = '\0';
1085                                                 break;
1086                                         }
1087                                 }
1088                         }
1089                         if (*tmp1 == '\0') {        /* have unique */
1090                                 free(tmp1);
1091                                 return;
1092                         }
1093                         tmp = add_quote_for_spec_chars(tmp1);
1094                         free(tmp1);
1095                 } else {                        /* one match */
1096                         tmp = add_quote_for_spec_chars(matches[0]);
1097                         /* for next completion current found */
1098                         *lastWasTab = FALSE;
1099
1100                         len_found = strlen(tmp);
1101                         if (tmp[len_found-1] != '/') {
1102                                 tmp[len_found] = ' ';
1103                                 tmp[len_found+1] = '\0';
1104                         }
1105                 }
1106
1107                 len_found = strlen(tmp);
1108 #if !ENABLE_UNICODE_SUPPORT
1109                 /* have space to place the match? */
1110                 /* The result consists of three parts with these lengths: */
1111                 /* (cursor - recalc_pos) + len_found + (command_len - cursor) */
1112                 /* it simplifies into: */
1113                 if ((int)(len_found + command_len - recalc_pos) < S.maxsize) {
1114                         /* save tail */
1115                         strcpy(matchBuf, command_ps + cursor);
1116                         /* add match and tail */
1117                         sprintf(&command_ps[cursor - recalc_pos], "%s%s", tmp, matchBuf);
1118                         command_len = strlen(command_ps);
1119                         /* new pos */
1120                         recalc_pos = cursor - recalc_pos + len_found;
1121                         /* write out the matched command */
1122                         redraw(cmdedit_y, command_len - recalc_pos);
1123                 }
1124 #else
1125                 {
1126                         char command[MAX_LINELEN];
1127                         int len = save_string(command, sizeof(command));
1128                         /* have space to place the match? */
1129                         /* (cursor_mb - recalc_pos) + len_found + (len - cursor_mb) */
1130                         if ((int)(len_found + len - recalc_pos) < MAX_LINELEN) {
1131                                 /* save tail */
1132                                 strcpy(matchBuf, command + cursor_mb);
1133                                 /* where do we want to have cursor after all? */
1134                                 strcpy(&command[cursor_mb - recalc_pos], tmp);
1135                                 len = load_string(command, S.maxsize);
1136                                 /* add match and tail */
1137                                 sprintf(&command[cursor_mb - recalc_pos], "%s%s", tmp, matchBuf);
1138                                 command_len = load_string(command, S.maxsize);
1139                                 /* write out the matched command */
1140                                 redraw(cmdedit_y, command_len - len);
1141                         }
1142                 }
1143 #endif
1144                 free(tmp);
1145 #undef matchBuf
1146         } else {
1147                 /* Ok -- the last char was a TAB.  Since they
1148                  * just hit TAB again, print a list of all the
1149                  * available choices... */
1150                 if (matches && num_matches > 0) {
1151                         /* changed by goto_new_line() */
1152                         int sav_cursor = cursor;
1153
1154                         /* Go to the next line */
1155                         goto_new_line();
1156                         showfiles();
1157                         redraw(0, command_len - sav_cursor);
1158                 }
1159         }
1160 }
1161
1162 #endif  /* FEATURE_COMMAND_TAB_COMPLETION */
1163
1164
1165 line_input_t* FAST_FUNC new_line_input_t(int flags)
1166 {
1167         line_input_t *n = xzalloc(sizeof(*n));
1168         n->flags = flags;
1169         return n;
1170 }
1171
1172
1173 #if MAX_HISTORY > 0
1174
1175 static void save_command_ps_at_cur_history(void)
1176 {
1177         if (command_ps[0] != BB_NUL) {
1178                 int cur = state->cur_history;
1179                 free(state->history[cur]);
1180
1181 # if ENABLE_UNICODE_SUPPORT
1182                 {
1183                         char tbuf[MAX_LINELEN];
1184                         save_string(tbuf, sizeof(tbuf));
1185                         state->history[cur] = xstrdup(tbuf);
1186                 }
1187 # else
1188                 state->history[cur] = xstrdup(command_ps);
1189 # endif
1190         }
1191 }
1192
1193 /* state->flags is already checked to be nonzero */
1194 static int get_previous_history(void)
1195 {
1196         if ((state->flags & DO_HISTORY) && state->cur_history) {
1197                 save_command_ps_at_cur_history();
1198                 state->cur_history--;
1199                 return 1;
1200         }
1201         beep();
1202         return 0;
1203 }
1204
1205 static int get_next_history(void)
1206 {
1207         if (state->flags & DO_HISTORY) {
1208                 if (state->cur_history < state->cnt_history) {
1209                         save_command_ps_at_cur_history(); /* save the current history line */
1210                         return ++state->cur_history;
1211                 }
1212         }
1213         beep();
1214         return 0;
1215 }
1216
1217 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1218 /* We try to ensure that concurrent additions to the history
1219  * do not overwrite each other.
1220  * Otherwise shell users get unhappy.
1221  *
1222  * History file is trimmed lazily, when it grows several times longer
1223  * than configured MAX_HISTORY lines.
1224  */
1225
1226 static void free_line_input_t(line_input_t *n)
1227 {
1228         int i = n->cnt_history;
1229         while (i > 0)
1230                 free(n->history[--i]);
1231         free(n);
1232 }
1233
1234 /* state->flags is already checked to be nonzero */
1235 static void load_history(line_input_t *st_parm)
1236 {
1237         char *temp_h[MAX_HISTORY];
1238         char *line;
1239         FILE *fp;
1240         unsigned idx, i, line_len;
1241
1242         /* NB: do not trash old history if file can't be opened */
1243
1244         fp = fopen_for_read(st_parm->hist_file);
1245         if (fp) {
1246                 /* clean up old history */
1247                 for (idx = st_parm->cnt_history; idx > 0;) {
1248                         idx--;
1249                         free(st_parm->history[idx]);
1250                         st_parm->history[idx] = NULL;
1251                 }
1252
1253                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1254                 memset(temp_h, 0, sizeof(temp_h));
1255                 st_parm->cnt_history_in_file = idx = 0;
1256                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1257                         if (line[0] == '\0') {
1258                                 free(line);
1259                                 continue;
1260                         }
1261                         free(temp_h[idx]);
1262                         temp_h[idx] = line;
1263                         st_parm->cnt_history_in_file++;
1264                         idx++;
1265                         if (idx == MAX_HISTORY)
1266                                 idx = 0;
1267                 }
1268                 fclose(fp);
1269
1270                 /* find first non-NULL temp_h[], if any */
1271                 if (st_parm->cnt_history_in_file) {
1272                         while (temp_h[idx] == NULL) {
1273                                 idx++;
1274                                 if (idx == MAX_HISTORY)
1275                                         idx = 0;
1276                         }
1277                 }
1278
1279                 /* copy temp_h[] to st_parm->history[] */
1280                 for (i = 0; i < MAX_HISTORY;) {
1281                         line = temp_h[idx];
1282                         if (!line)
1283                                 break;
1284                         idx++;
1285                         if (idx == MAX_HISTORY)
1286                                 idx = 0;
1287                         line_len = strlen(line);
1288                         if (line_len >= MAX_LINELEN)
1289                                 line[MAX_LINELEN-1] = '\0';
1290                         st_parm->history[i++] = line;
1291                 }
1292                 st_parm->cnt_history = i;
1293         }
1294 }
1295
1296 /* state->flags is already checked to be nonzero */
1297 static void save_history(char *str)
1298 {
1299         int fd;
1300         int len, len2;
1301
1302         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0666);
1303         if (fd < 0)
1304                 return;
1305         xlseek(fd, 0, SEEK_END); /* paranoia */
1306         len = strlen(str);
1307         str[len] = '\n'; /* we (try to) do atomic write */
1308         len2 = full_write(fd, str, len + 1);
1309         str[len] = '\0';
1310         close(fd);
1311         if (len2 != len + 1)
1312                 return; /* "wtf?" */
1313
1314         /* did we write so much that history file needs trimming? */
1315         state->cnt_history_in_file++;
1316         if (state->cnt_history_in_file > MAX_HISTORY * 4) {
1317                 FILE *fp;
1318                 char *new_name;
1319                 line_input_t *st_temp;
1320                 int i;
1321
1322                 /* we may have concurrently written entries from others.
1323                  * load them */
1324                 st_temp = new_line_input_t(state->flags);
1325                 st_temp->hist_file = state->hist_file;
1326                 load_history(st_temp);
1327
1328                 /* write out temp file and replace hist_file atomically */
1329                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1330                 fp = fopen_for_write(new_name);
1331                 if (fp) {
1332                         for (i = 0; i < st_temp->cnt_history; i++)
1333                                 fprintf(fp, "%s\n", st_temp->history[i]);
1334                         fclose(fp);
1335                         if (rename(new_name, state->hist_file) == 0)
1336                                 state->cnt_history_in_file = st_temp->cnt_history;
1337                 }
1338                 free(new_name);
1339                 free_line_input_t(st_temp);
1340         }
1341 }
1342 # else
1343 #  define load_history(a) ((void)0)
1344 #  define save_history(a) ((void)0)
1345 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1346
1347 static void remember_in_history(char *str)
1348 {
1349         int i;
1350
1351         if (!(state->flags & DO_HISTORY))
1352                 return;
1353         if (str[0] == '\0')
1354                 return;
1355         i = state->cnt_history;
1356         /* Don't save dupes */
1357         if (i && strcmp(state->history[i-1], str) == 0)
1358                 return;
1359
1360         free(state->history[MAX_HISTORY]); /* redundant, paranoia */
1361         state->history[MAX_HISTORY] = NULL; /* redundant, paranoia */
1362
1363         /* If history[] is full, remove the oldest command */
1364         /* we need to keep history[MAX_HISTORY] empty, hence >=, not > */
1365         if (i >= MAX_HISTORY) {
1366                 free(state->history[0]);
1367                 for (i = 0; i < MAX_HISTORY-1; i++)
1368                         state->history[i] = state->history[i+1];
1369                 /* i == MAX_HISTORY-1 */
1370         }
1371         /* i <= MAX_HISTORY-1 */
1372         state->history[i++] = xstrdup(str);
1373         /* i <= MAX_HISTORY */
1374         state->cur_history = i;
1375         state->cnt_history = i;
1376 # if MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
1377         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1378                 save_history(str);
1379 # endif
1380         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines++;)
1381 }
1382
1383 #else /* MAX_HISTORY == 0 */
1384 # define remember_in_history(a) ((void)0)
1385 #endif /* MAX_HISTORY */
1386
1387
1388 #if ENABLE_FEATURE_EDITING_VI
1389 /*
1390  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1391  */
1392 static void
1393 vi_Word_motion(int eat)
1394 {
1395         CHAR_T *command = command_ps;
1396
1397         while (cursor < command_len && !BB_isspace(command[cursor]))
1398                 input_forward();
1399         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1400                 input_forward();
1401 }
1402
1403 static void
1404 vi_word_motion(int eat)
1405 {
1406         CHAR_T *command = command_ps;
1407
1408         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1409                 while (cursor < command_len
1410                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1411                 ) {
1412                         input_forward();
1413                 }
1414         } else if (BB_ispunct(command[cursor])) {
1415                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1416                         input_forward();
1417         }
1418
1419         if (cursor < command_len)
1420                 input_forward();
1421
1422         if (eat) {
1423                 while (cursor < command_len && BB_isspace(command[cursor]))
1424                         input_forward();
1425         }
1426 }
1427
1428 static void
1429 vi_End_motion(void)
1430 {
1431         CHAR_T *command = command_ps;
1432
1433         input_forward();
1434         while (cursor < command_len && BB_isspace(command[cursor]))
1435                 input_forward();
1436         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1437                 input_forward();
1438 }
1439
1440 static void
1441 vi_end_motion(void)
1442 {
1443         CHAR_T *command = command_ps;
1444
1445         if (cursor >= command_len-1)
1446                 return;
1447         input_forward();
1448         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1449                 input_forward();
1450         if (cursor >= command_len-1)
1451                 return;
1452         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1453                 while (cursor < command_len-1
1454                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1455                 ) {
1456                         input_forward();
1457                 }
1458         } else if (BB_ispunct(command[cursor])) {
1459                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1460                         input_forward();
1461         }
1462 }
1463
1464 static void
1465 vi_Back_motion(void)
1466 {
1467         CHAR_T *command = command_ps;
1468
1469         while (cursor > 0 && BB_isspace(command[cursor-1]))
1470                 input_backward(1);
1471         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1472                 input_backward(1);
1473 }
1474
1475 static void
1476 vi_back_motion(void)
1477 {
1478         CHAR_T *command = command_ps;
1479
1480         if (cursor <= 0)
1481                 return;
1482         input_backward(1);
1483         while (cursor > 0 && BB_isspace(command[cursor]))
1484                 input_backward(1);
1485         if (cursor <= 0)
1486                 return;
1487         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1488                 while (cursor > 0
1489                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1490                 ) {
1491                         input_backward(1);
1492                 }
1493         } else if (BB_ispunct(command[cursor])) {
1494                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1495                         input_backward(1);
1496         }
1497 }
1498 #endif
1499
1500 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1501 static void ctrl_left(void)
1502 {
1503         CHAR_T *command = command_ps;
1504
1505         while (1) {
1506                 CHAR_T c;
1507
1508                 input_backward(1);
1509                 if (cursor == 0)
1510                         break;
1511                 c = command[cursor];
1512                 if (c != ' ' && !BB_ispunct(c)) {
1513                         /* we reached a "word" delimited by spaces/punct.
1514                          * go to its beginning */
1515                         while (1) {
1516                                 c = command[cursor - 1];
1517                                 if (c == ' ' || BB_ispunct(c))
1518                                         break;
1519                                 input_backward(1);
1520                                 if (cursor == 0)
1521                                         break;
1522                         }
1523                         break;
1524                 }
1525         }
1526 }
1527 static void ctrl_right(void)
1528 {
1529         CHAR_T *command = command_ps;
1530
1531         while (1) {
1532                 CHAR_T c;
1533
1534                 c = command[cursor];
1535                 if (c == BB_NUL)
1536                         break;
1537                 if (c != ' ' && !BB_ispunct(c)) {
1538                         /* we reached a "word" delimited by spaces/punct.
1539                          * go to its end + 1 */
1540                         while (1) {
1541                                 input_forward();
1542                                 c = command[cursor];
1543                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1544                                         break;
1545                         }
1546                         break;
1547                 }
1548                 input_forward();
1549         }
1550 }
1551
1552
1553 /*
1554  * read_line_input and its helpers
1555  */
1556
1557 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1558 static void ask_terminal(void)
1559 {
1560         /* Ask terminal where is the cursor now.
1561          * lineedit_read_key handles response and corrects
1562          * our idea of current cursor position.
1563          * Testcase: run "echo -n long_line_long_line_long_line",
1564          * then type in a long, wrapping command and try to
1565          * delete it using backspace key.
1566          * Note: we print it _after_ prompt, because
1567          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1568          */
1569         /* Problem: if there is buffered input on stdin,
1570          * the response will be delivered later,
1571          * possibly to an unsuspecting application.
1572          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1573          * Result:
1574          * ~/srcdevel/bbox/fix/busybox.t4 #
1575          * ~/srcdevel/bbox/fix/busybox.t4 #
1576          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1577          * ~/srcdevel/bbox/fix/busybox.t4 #
1578          *
1579          * Checking for input with poll only makes the race narrower,
1580          * I still can trigger it. Strace:
1581          *
1582          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1583          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1584          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1585          * poll([{fd=0, events=POLLIN}], 1, 4294967295) = 1 ([{fd=0, revents=POLLIN}])
1586          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1587          */
1588         struct pollfd pfd;
1589
1590         pfd.fd = STDIN_FILENO;
1591         pfd.events = POLLIN;
1592         if (safe_poll(&pfd, 1, 0) == 0) {
1593                 S.sent_ESC_br6n = 1;
1594                 out1str("\033" "[6n");
1595                 fflush_all(); /* make terminal see it ASAP! */
1596         }
1597 }
1598 #else
1599 #define ask_terminal() ((void)0)
1600 #endif
1601
1602 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1603 static void parse_and_put_prompt(const char *prmt_ptr)
1604 {
1605         cmdedit_prompt = prmt_ptr;
1606         cmdedit_prmt_len = strlen(prmt_ptr);
1607         put_prompt();
1608 }
1609 #else
1610 static void parse_and_put_prompt(const char *prmt_ptr)
1611 {
1612         int prmt_len = 0;
1613         size_t cur_prmt_len = 0;
1614         char flg_not_length = '[';
1615         char *prmt_mem_ptr = xzalloc(1);
1616         char *cwd_buf = xrealloc_getcwd_or_warn(NULL);
1617         char cbuf[2];
1618         char c;
1619         char *pbuf;
1620
1621         cmdedit_prmt_len = 0;
1622
1623         if (!cwd_buf) {
1624                 cwd_buf = (char *)bb_msg_unknown;
1625         }
1626
1627         cbuf[1] = '\0'; /* never changes */
1628
1629         while (*prmt_ptr) {
1630                 char *free_me = NULL;
1631
1632                 pbuf = cbuf;
1633                 c = *prmt_ptr++;
1634                 if (c == '\\') {
1635                         const char *cp = prmt_ptr;
1636                         int l;
1637
1638                         c = bb_process_escape_sequence(&prmt_ptr);
1639                         if (prmt_ptr == cp) {
1640                                 if (*cp == '\0')
1641                                         break;
1642                                 c = *prmt_ptr++;
1643
1644                                 switch (c) {
1645 # if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
1646                                 case 'u':
1647                                         pbuf = user_buf ? user_buf : (char*)"";
1648                                         break;
1649 # endif
1650                                 case 'h':
1651                                         pbuf = free_me = safe_gethostname();
1652                                         *strchrnul(pbuf, '.') = '\0';
1653                                         break;
1654                                 case '$':
1655                                         c = (geteuid() == 0 ? '#' : '$');
1656                                         break;
1657 # if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
1658                                 case 'w':
1659                                         /* /home/user[/something] -> ~[/something] */
1660                                         pbuf = cwd_buf;
1661                                         l = strlen(home_pwd_buf);
1662                                         if (l != 0
1663                                          && strncmp(home_pwd_buf, cwd_buf, l) == 0
1664                                          && (cwd_buf[l]=='/' || cwd_buf[l]=='\0')
1665                                          && strlen(cwd_buf + l) < PATH_MAX
1666                                         ) {
1667                                                 pbuf = free_me = xasprintf("~%s", cwd_buf + l);
1668                                         }
1669                                         break;
1670 # endif
1671                                 case 'W':
1672                                         pbuf = cwd_buf;
1673                                         cp = strrchr(pbuf, '/');
1674                                         if (cp != NULL && cp != pbuf)
1675                                                 pbuf += (cp-pbuf) + 1;
1676                                         break;
1677                                 case '!':
1678                                         pbuf = free_me = xasprintf("%d", num_ok_lines);
1679                                         break;
1680                                 case 'e': case 'E':     /* \e \E = \033 */
1681                                         c = '\033';
1682                                         break;
1683                                 case 'x': case 'X': {
1684                                         char buf2[4];
1685                                         for (l = 0; l < 3;) {
1686                                                 unsigned h;
1687                                                 buf2[l++] = *prmt_ptr;
1688                                                 buf2[l] = '\0';
1689                                                 h = strtoul(buf2, &pbuf, 16);
1690                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1691                                                         buf2[--l] = '\0';
1692                                                         break;
1693                                                 }
1694                                                 prmt_ptr++;
1695                                         }
1696                                         c = (char)strtoul(buf2, NULL, 16);
1697                                         if (c == 0)
1698                                                 c = '?';
1699                                         pbuf = cbuf;
1700                                         break;
1701                                 }
1702                                 case '[': case ']':
1703                                         if (c == flg_not_length) {
1704                                                 flg_not_length = (flg_not_length == '[' ? ']' : '[');
1705                                                 continue;
1706                                         }
1707                                         break;
1708                                 } /* switch */
1709                         } /* if */
1710                 } /* if */
1711                 cbuf[0] = c;
1712                 cur_prmt_len = strlen(pbuf);
1713                 prmt_len += cur_prmt_len;
1714                 if (flg_not_length != ']')
1715                         cmdedit_prmt_len += cur_prmt_len;
1716                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_len+1), pbuf);
1717                 free(free_me);
1718         } /* while */
1719
1720         if (cwd_buf != (char *)bb_msg_unknown)
1721                 free(cwd_buf);
1722         cmdedit_prompt = prmt_mem_ptr;
1723         put_prompt();
1724 }
1725 #endif
1726
1727 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1728 {
1729         cmdedit_termw = w;
1730         if (redraw_flg) {
1731                 /* new y for current cursor */
1732                 int new_y = (cursor + cmdedit_prmt_len) / w;
1733                 /* redraw */
1734                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1735                 fflush_all();
1736         }
1737 }
1738
1739 static void win_changed(int nsig)
1740 {
1741         unsigned width;
1742         get_terminal_width_height(0, &width, NULL);
1743         cmdedit_setwidth(width, nsig /* - just a yes/no flag */);
1744         if (nsig == SIGWINCH)
1745                 signal(SIGWINCH, win_changed); /* rearm ourself */
1746 }
1747
1748 static int lineedit_read_key(char *read_key_buffer)
1749 {
1750         int64_t ic;
1751         int timeout = -1;
1752 #if ENABLE_UNICODE_SUPPORT
1753         char unicode_buf[MB_CUR_MAX + 1];
1754         int unicode_idx = 0;
1755 #endif
1756
1757         while (1) {
1758                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
1759                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
1760                  * insist on full MB_CUR_MAX buffer to declare input like
1761                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
1762                  *
1763                  * Note: read_key sets errno to 0 on success.
1764                  */
1765                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
1766                 if (errno) {
1767 #if ENABLE_UNICODE_SUPPORT
1768                         if (errno == EAGAIN && unicode_idx != 0)
1769                                 goto pushback;
1770 #endif
1771                         break;
1772                 }
1773
1774 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1775                 if ((int32_t)ic == KEYCODE_CURSOR_POS
1776                  && S.sent_ESC_br6n
1777                 ) {
1778                         S.sent_ESC_br6n = 0;
1779                         if (cursor == 0) { /* otherwise it may be bogus */
1780                                 int col = ((ic >> 32) & 0x7fff) - 1;
1781                                 if (col > cmdedit_prmt_len) {
1782                                         cmdedit_x += (col - cmdedit_prmt_len);
1783                                         while (cmdedit_x >= cmdedit_termw) {
1784                                                 cmdedit_x -= cmdedit_termw;
1785                                                 cmdedit_y++;
1786                                         }
1787                                 }
1788                         }
1789                         continue;
1790                 }
1791 #endif
1792
1793 #if ENABLE_UNICODE_SUPPORT
1794                 if (unicode_status == UNICODE_ON) {
1795                         wchar_t wc;
1796
1797                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
1798                                 break;
1799                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
1800
1801                         unicode_buf[unicode_idx++] = ic;
1802                         unicode_buf[unicode_idx] = '\0';
1803                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
1804                                 /* Not (yet?) a valid unicode char */
1805                                 if (unicode_idx < MB_CUR_MAX) {
1806                                         timeout = 50;
1807                                         continue;
1808                                 }
1809  pushback:
1810                                 /* Invalid sequence. Save all "bad bytes" except first */
1811                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
1812 # if !ENABLE_UNICODE_PRESERVE_BROKEN
1813                                 ic = CONFIG_SUBST_WCHAR;
1814 # else
1815                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
1816 # endif
1817                         } else {
1818                                 /* Valid unicode char, return its code */
1819                                 ic = wc;
1820                         }
1821                 }
1822 #endif
1823                 break;
1824         }
1825
1826         return ic;
1827 }
1828
1829 #if ENABLE_UNICODE_BIDI_SUPPORT
1830 static int isrtl_str(void)
1831 {
1832         int idx = cursor;
1833
1834         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
1835                 idx++;
1836         return unicode_bidi_isrtl(command_ps[idx]);
1837 }
1838 #else
1839 # define isrtl_str() 0
1840 #endif
1841
1842 /* leave out the "vi-mode"-only case labels if vi editing isn't
1843  * configured. */
1844 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
1845
1846 /* convert uppercase ascii to equivalent control char, for readability */
1847 #undef CTRL
1848 #define CTRL(a) ((a) & ~0x40)
1849
1850 /* maxsize must be >= 2.
1851  * Returns:
1852  * -1 on read errors or EOF, or on bare Ctrl-D,
1853  * 0  on ctrl-C (the line entered is still returned in 'command'),
1854  * >0 length of input string, including terminating '\n'
1855  */
1856 int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, line_input_t *st)
1857 {
1858         int len;
1859 #if ENABLE_FEATURE_TAB_COMPLETION
1860         smallint lastWasTab = FALSE;
1861 #endif
1862         smallint break_out = 0;
1863 #if ENABLE_FEATURE_EDITING_VI
1864         smallint vi_cmdmode = 0;
1865 #endif
1866         struct termios initial_settings;
1867         struct termios new_settings;
1868         char read_key_buffer[KEYCODE_BUFFER_SIZE];
1869
1870         INIT_S();
1871
1872         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
1873          || !(initial_settings.c_lflag & ECHO)
1874         ) {
1875                 /* Happens when e.g. stty -echo was run before */
1876                 parse_and_put_prompt(prompt);
1877                 /* fflush_all(); - done by parse_and_put_prompt */
1878                 if (fgets(command, maxsize, stdin) == NULL)
1879                         len = -1; /* EOF or error */
1880                 else
1881                         len = strlen(command);
1882                 DEINIT_S();
1883                 return len;
1884         }
1885
1886         init_unicode();
1887
1888 // FIXME: audit & improve this
1889         if (maxsize > MAX_LINELEN)
1890                 maxsize = MAX_LINELEN;
1891         S.maxsize = maxsize;
1892
1893         /* With null flags, no other fields are ever used */
1894         state = st ? st : (line_input_t*) &const_int_0;
1895 #if MAX_HISTORY > 0
1896 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1897         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1898                 if (state->cnt_history == 0)
1899                         load_history(state);
1900 # endif
1901         if (state->flags & DO_HISTORY)
1902                 state->cur_history = state->cnt_history;
1903 #endif
1904
1905         /* prepare before init handlers */
1906         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
1907         command_len = 0;
1908 #if ENABLE_UNICODE_SUPPORT
1909         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
1910 #else
1911         command_ps = command;
1912         command[0] = '\0';
1913 #endif
1914 #define command command_must_not_be_used
1915
1916         new_settings = initial_settings;
1917         new_settings.c_lflag &= ~ICANON;        /* unbuffered input */
1918         /* Turn off echoing and CTRL-C, so we can trap it */
1919         new_settings.c_lflag &= ~(ECHO | ECHONL | ISIG);
1920         /* Hmm, in linux c_cc[] is not parsed if ICANON is off */
1921         new_settings.c_cc[VMIN] = 1;
1922         new_settings.c_cc[VTIME] = 0;
1923         /* Turn off CTRL-C, so we can trap it */
1924 #ifndef _POSIX_VDISABLE
1925 # define _POSIX_VDISABLE '\0'
1926 #endif
1927         new_settings.c_cc[VINTR] = _POSIX_VDISABLE;
1928         tcsetattr_stdin_TCSANOW(&new_settings);
1929
1930         /* Now initialize things */
1931         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
1932         win_changed(0); /* do initial resizing */
1933 #if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
1934         {
1935                 struct passwd *entry;
1936
1937                 entry = getpwuid(geteuid());
1938                 if (entry) {
1939                         user_buf = xstrdup(entry->pw_name);
1940                         home_pwd_buf = xstrdup(entry->pw_dir);
1941                 }
1942         }
1943 #endif
1944
1945 #if 0
1946         for (i = 0; i <= MAX_HISTORY; i++)
1947                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
1948         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
1949 #endif
1950
1951         /* Print out the command prompt, optionally ask where cursor is */
1952         parse_and_put_prompt(prompt);
1953         ask_terminal();
1954
1955         read_key_buffer[0] = 0;
1956         while (1) {
1957                 /*
1958                  * The emacs and vi modes share much of the code in the big
1959                  * command loop.  Commands entered when in vi's command mode
1960                  * (aka "escape mode") get an extra bit added to distinguish
1961                  * them - this keeps them from being self-inserted. This
1962                  * clutters the big switch a bit, but keeps all the code
1963                  * in one place.
1964                  */
1965                 enum {
1966                         VI_CMDMODE_BIT = 0x40000000,
1967                         /* 0x80000000 bit flags KEYCODE_xxx */
1968                 };
1969                 int32_t ic, ic_raw;
1970
1971                 fflush_all();
1972                 ic = ic_raw = lineedit_read_key(read_key_buffer);
1973
1974 #if ENABLE_FEATURE_EDITING_VI
1975                 newdelflag = 1;
1976                 if (vi_cmdmode) {
1977                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
1978                          * change ic if it contains one of them: */
1979                         ic |= VI_CMDMODE_BIT;
1980                 }
1981 #endif
1982
1983                 switch (ic) {
1984                 case '\n':
1985                 case '\r':
1986                 vi_case('\n'|VI_CMDMODE_BIT:)
1987                 vi_case('\r'|VI_CMDMODE_BIT:)
1988                         /* Enter */
1989                         goto_new_line();
1990                         break_out = 1;
1991                         break;
1992                 case CTRL('A'):
1993                 vi_case('0'|VI_CMDMODE_BIT:)
1994                         /* Control-a -- Beginning of line */
1995                         input_backward(cursor);
1996                         break;
1997                 case CTRL('B'):
1998                 vi_case('h'|VI_CMDMODE_BIT:)
1999                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2000                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2001                         input_backward(1); /* Move back one character */
2002                         break;
2003                 case CTRL('E'):
2004                 vi_case('$'|VI_CMDMODE_BIT:)
2005                         /* Control-e -- End of line */
2006                         put_till_end_and_adv_cursor();
2007                         break;
2008                 case CTRL('F'):
2009                 vi_case('l'|VI_CMDMODE_BIT:)
2010                 vi_case(' '|VI_CMDMODE_BIT:)
2011                         input_forward(); /* Move forward one character */
2012                         break;
2013                 case '\b':   /* ^H */
2014                 case '\x7f': /* DEL */
2015                         if (!isrtl_str())
2016                                 input_backspace();
2017                         else
2018                                 input_delete(0);
2019                         break;
2020                 case KEYCODE_DELETE:
2021                         if (!isrtl_str())
2022                                 input_delete(0);
2023                         else
2024                                 input_backspace();
2025                         break;
2026 #if ENABLE_FEATURE_TAB_COMPLETION
2027                 case '\t':
2028                         input_tab(&lastWasTab);
2029                         break;
2030 #endif
2031                 case CTRL('K'):
2032                         /* Control-k -- clear to end of line */
2033                         command_ps[cursor] = BB_NUL;
2034                         command_len = cursor;
2035                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2036                         break;
2037                 case CTRL('L'):
2038                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2039                         /* Control-l -- clear screen */
2040                         printf("\033[H"); /* cursor to top,left */
2041                         redraw(0, command_len - cursor);
2042                         break;
2043 #if MAX_HISTORY > 0
2044                 case CTRL('N'):
2045                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2046                 vi_case('j'|VI_CMDMODE_BIT:)
2047                         /* Control-n -- Get next command in history */
2048                         if (get_next_history())
2049                                 goto rewrite_line;
2050                         break;
2051                 case CTRL('P'):
2052                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2053                 vi_case('k'|VI_CMDMODE_BIT:)
2054                         /* Control-p -- Get previous command from history */
2055                         if (get_previous_history())
2056                                 goto rewrite_line;
2057                         break;
2058 #endif
2059                 case CTRL('U'):
2060                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2061                         /* Control-U -- Clear line before cursor */
2062                         if (cursor) {
2063                                 command_len -= cursor;
2064                                 memmove(command_ps, command_ps + cursor,
2065                                         (command_len + 1) * sizeof(command_ps[0]));
2066                                 redraw(cmdedit_y, command_len);
2067                         }
2068                         break;
2069                 case CTRL('W'):
2070                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2071                         /* Control-W -- Remove the last word */
2072                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2073                                 input_backspace();
2074                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2075                                 input_backspace();
2076                         break;
2077
2078 #if ENABLE_FEATURE_EDITING_VI
2079                 case 'i'|VI_CMDMODE_BIT:
2080                         vi_cmdmode = 0;
2081                         break;
2082                 case 'I'|VI_CMDMODE_BIT:
2083                         input_backward(cursor);
2084                         vi_cmdmode = 0;
2085                         break;
2086                 case 'a'|VI_CMDMODE_BIT:
2087                         input_forward();
2088                         vi_cmdmode = 0;
2089                         break;
2090                 case 'A'|VI_CMDMODE_BIT:
2091                         put_till_end_and_adv_cursor();
2092                         vi_cmdmode = 0;
2093                         break;
2094                 case 'x'|VI_CMDMODE_BIT:
2095                         input_delete(1);
2096                         break;
2097                 case 'X'|VI_CMDMODE_BIT:
2098                         if (cursor > 0) {
2099                                 input_backward(1);
2100                                 input_delete(1);
2101                         }
2102                         break;
2103                 case 'W'|VI_CMDMODE_BIT:
2104                         vi_Word_motion(1);
2105                         break;
2106                 case 'w'|VI_CMDMODE_BIT:
2107                         vi_word_motion(1);
2108                         break;
2109                 case 'E'|VI_CMDMODE_BIT:
2110                         vi_End_motion();
2111                         break;
2112                 case 'e'|VI_CMDMODE_BIT:
2113                         vi_end_motion();
2114                         break;
2115                 case 'B'|VI_CMDMODE_BIT:
2116                         vi_Back_motion();
2117                         break;
2118                 case 'b'|VI_CMDMODE_BIT:
2119                         vi_back_motion();
2120                         break;
2121                 case 'C'|VI_CMDMODE_BIT:
2122                         vi_cmdmode = 0;
2123                         /* fall through */
2124                 case 'D'|VI_CMDMODE_BIT:
2125                         goto clear_to_eol;
2126
2127                 case 'c'|VI_CMDMODE_BIT:
2128                         vi_cmdmode = 0;
2129                         /* fall through */
2130                 case 'd'|VI_CMDMODE_BIT: {
2131                         int nc, sc;
2132
2133                         ic = lineedit_read_key(read_key_buffer);
2134                         if (errno) /* error */
2135                                 goto prepare_to_die;
2136                         if (ic == ic_raw) { /* "cc", "dd" */
2137                                 input_backward(cursor);
2138                                 goto clear_to_eol;
2139                                 break;
2140                         }
2141
2142                         sc = cursor;
2143                         switch (ic) {
2144                         case 'w':
2145                         case 'W':
2146                         case 'e':
2147                         case 'E':
2148                                 switch (ic) {
2149                                 case 'w':   /* "dw", "cw" */
2150                                         vi_word_motion(vi_cmdmode);
2151                                         break;
2152                                 case 'W':   /* 'dW', 'cW' */
2153                                         vi_Word_motion(vi_cmdmode);
2154                                         break;
2155                                 case 'e':   /* 'de', 'ce' */
2156                                         vi_end_motion();
2157                                         input_forward();
2158                                         break;
2159                                 case 'E':   /* 'dE', 'cE' */
2160                                         vi_End_motion();
2161                                         input_forward();
2162                                         break;
2163                                 }
2164                                 nc = cursor;
2165                                 input_backward(cursor - sc);
2166                                 while (nc-- > cursor)
2167                                         input_delete(1);
2168                                 break;
2169                         case 'b':  /* "db", "cb" */
2170                         case 'B':  /* implemented as B */
2171                                 if (ic == 'b')
2172                                         vi_back_motion();
2173                                 else
2174                                         vi_Back_motion();
2175                                 while (sc-- > cursor)
2176                                         input_delete(1);
2177                                 break;
2178                         case ' ':  /* "d ", "c " */
2179                                 input_delete(1);
2180                                 break;
2181                         case '$':  /* "d$", "c$" */
2182  clear_to_eol:
2183                                 while (cursor < command_len)
2184                                         input_delete(1);
2185                                 break;
2186                         }
2187                         break;
2188                 }
2189                 case 'p'|VI_CMDMODE_BIT:
2190                         input_forward();
2191                         /* fallthrough */
2192                 case 'P'|VI_CMDMODE_BIT:
2193                         put();
2194                         break;
2195                 case 'r'|VI_CMDMODE_BIT:
2196 //FIXME: unicode case?
2197                         ic = lineedit_read_key(read_key_buffer);
2198                         if (errno) /* error */
2199                                 goto prepare_to_die;
2200                         if (ic < ' ' || ic > 255) {
2201                                 beep();
2202                         } else {
2203                                 command_ps[cursor] = ic;
2204                                 bb_putchar(ic);
2205                                 bb_putchar('\b');
2206                         }
2207                         break;
2208                 case '\x1b': /* ESC */
2209                         if (state->flags & VI_MODE) {
2210                                 /* insert mode --> command mode */
2211                                 vi_cmdmode = 1;
2212                                 input_backward(1);
2213                         }
2214                         break;
2215 #endif /* FEATURE_COMMAND_EDITING_VI */
2216
2217 #if MAX_HISTORY > 0
2218                 case KEYCODE_UP:
2219                         if (get_previous_history())
2220                                 goto rewrite_line;
2221                         beep();
2222                         break;
2223                 case KEYCODE_DOWN:
2224                         if (!get_next_history())
2225                                 break;
2226  rewrite_line:
2227                         /* Rewrite the line with the selected history item */
2228                         /* change command */
2229                         command_len = load_string(state->history[state->cur_history] ?
2230                                         state->history[state->cur_history] : "", maxsize);
2231                         /* redraw and go to eol (bol, in vi) */
2232                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2233                         break;
2234 #endif
2235                 case KEYCODE_RIGHT:
2236                         input_forward();
2237                         break;
2238                 case KEYCODE_LEFT:
2239                         input_backward(1);
2240                         break;
2241                 case KEYCODE_CTRL_LEFT:
2242                         ctrl_left();
2243                         break;
2244                 case KEYCODE_CTRL_RIGHT:
2245                         ctrl_right();
2246                         break;
2247                 case KEYCODE_HOME:
2248                         input_backward(cursor);
2249                         break;
2250                 case KEYCODE_END:
2251                         put_till_end_and_adv_cursor();
2252                         break;
2253
2254                 default:
2255                         if (initial_settings.c_cc[VINTR] != 0
2256                          && ic_raw == initial_settings.c_cc[VINTR]
2257                         ) {
2258                                 /* Ctrl-C (usually) - stop gathering input */
2259                                 goto_new_line();
2260                                 command_len = 0;
2261                                 break_out = -1; /* "do not append '\n'" */
2262                                 break;
2263                         }
2264                         if (initial_settings.c_cc[VEOF] != 0
2265                          && ic_raw == initial_settings.c_cc[VEOF]
2266                         ) {
2267                                 /* Ctrl-D (usually) - delete one character,
2268                                  * or exit if len=0 and no chars to delete */
2269                                 if (command_len == 0) {
2270                                         errno = 0;
2271 #if ENABLE_FEATURE_EDITING_VI
2272  prepare_to_die:
2273 #endif
2274                                         break_out = command_len = -1;
2275                                         break;
2276                                 }
2277                                 input_delete(0);
2278                                 break;
2279                         }
2280 //                      /* Control-V -- force insert of next char */
2281 //                      if (c == CTRL('V')) {
2282 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2283 //                                      goto prepare_to_die;
2284 //                              if (c == 0) {
2285 //                                      beep();
2286 //                                      break;
2287 //                              }
2288 //                      }
2289                         if (ic < ' '
2290                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2291                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2292                         ) {
2293                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2294                                  * and vi mode ignores unexpected chars.
2295                                  * Otherwise, we are here if ic is a
2296                                  * control char or an unhandled ESC sequence,
2297                                  * which is also ignored.
2298                                  */
2299                                 break;
2300                         }
2301                         if ((int)command_len >= (maxsize - 2)) {
2302                                 /* Not enough space for the char and EOL */
2303                                 break;
2304                         }
2305
2306                         command_len++;
2307                         if (cursor == (command_len - 1)) {
2308                                 /* We are at the end, append */
2309                                 command_ps[cursor] = ic;
2310                                 command_ps[cursor + 1] = BB_NUL;
2311                                 put_cur_glyph_and_inc_cursor();
2312                                 if (unicode_bidi_isrtl(ic))
2313                                         input_backward(1);
2314                         } else {
2315                                 /* In the middle, insert */
2316                                 int sc = cursor;
2317
2318                                 memmove(command_ps + sc + 1, command_ps + sc,
2319                                         (command_len - sc) * sizeof(command_ps[0]));
2320                                 command_ps[sc] = ic;
2321                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2322                                 if (!isrtl_str())
2323                                         sc++; /* no */
2324                                 put_till_end_and_adv_cursor();
2325                                 /* to prev x pos + 1 */
2326                                 input_backward(cursor - sc);
2327                         }
2328                         break;
2329                 } /* switch (ic) */
2330
2331                 if (break_out)
2332                         break;
2333
2334 #if ENABLE_FEATURE_TAB_COMPLETION
2335                 if (ic_raw != '\t')
2336                         lastWasTab = FALSE;
2337 #endif
2338         } /* while (1) */
2339
2340 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2341         if (S.sent_ESC_br6n) {
2342                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2343                  * We sent "ESC [ 6 n", but got '\n' first, and
2344                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2345                  * It's bad already and not much can be done with it
2346                  * (it _will_ be visible for the next process to read stdin),
2347                  * but without this delay it even shows up on the screen
2348                  * as garbage because we restore echo settings with tcsetattr
2349                  * before it comes in. UGLY!
2350                  */
2351                 usleep(20*1000);
2352         }
2353 #endif
2354
2355 /* Stop bug catching using "command_must_not_be_used" trick */
2356 #undef command
2357
2358 #if ENABLE_UNICODE_SUPPORT
2359         command[0] = '\0';
2360         if (command_len > 0)
2361                 command_len = save_string(command, maxsize - 1);
2362         free(command_ps);
2363 #endif
2364
2365         if (command_len > 0)
2366                 remember_in_history(command);
2367
2368         if (break_out > 0) {
2369                 command[command_len++] = '\n';
2370                 command[command_len] = '\0';
2371         }
2372
2373 #if ENABLE_FEATURE_TAB_COMPLETION
2374         free_tab_completion_data();
2375 #endif
2376
2377         /* restore initial_settings */
2378         tcsetattr_stdin_TCSANOW(&initial_settings);
2379         /* restore SIGWINCH handler */
2380         signal(SIGWINCH, previous_SIGWINCH_handler);
2381         fflush_all();
2382
2383         len = command_len;
2384         DEINIT_S();
2385
2386         return len; /* can't return command_len, DEINIT_S() destroys it */
2387 }
2388
2389 #else
2390
2391 #undef read_line_input
2392 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2393 {
2394         fputs(prompt, stdout);
2395         fflush_all();
2396         fgets(command, maxsize, stdin);
2397         return strlen(command);
2398 }
2399
2400 #endif  /* FEATURE_EDITING */
2401
2402
2403 /*
2404  * Testing
2405  */
2406
2407 #ifdef TEST
2408
2409 #include <locale.h>
2410
2411 const char *applet_name = "debug stuff usage";
2412
2413 int main(int argc, char **argv)
2414 {
2415         char buff[MAX_LINELEN];
2416         char *prompt =
2417 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2418                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2419                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2420                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2421 #else
2422                 "% ";
2423 #endif
2424
2425         while (1) {
2426                 int l;
2427                 l = read_line_input(prompt, buff);
2428                 if (l <= 0 || buff[l-1] != '\n')
2429                         break;
2430                 buff[l-1] = 0;
2431                 printf("*** read_line_input() returned line =%s=\n", buff);
2432         }
2433         printf("*** read_line_input() detect ^D\n");
2434         return 0;
2435 }
2436
2437 #endif  /* TEST */