libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16 /*
  17  * Usage and known bugs:
  18  * Terminal key codes are not extensive, more needs to be added.
  19  * This version was created on Debian GNU/Linux 2.x.
  20  * Delete, Backspace, Home, End, and the arrow keys were tested
  21  * to work in an Xterm and console. Ctrl-A also works as Home.
  22  * Ctrl-E also works as End.
  23  *
  24  * The following readline-like commands are not implemented:
  25  * CTL-t -- Transpose two characters
  26  *
  27  * lineedit does not know that the terminal escape sequences do not
  28  * take up space on the screen. The redisplay code assumes, unless
  29  * told otherwise, that each character in the prompt is a printable
  30  * character that takes up one character position on the screen.
  31  * You need to tell lineedit that some sequences of characters
  32  * in the prompt take up no screen space. Compatibly with readline,
  33  * use the \[ escape to begin a sequence of non-printing characters,
  34  * and the \] escape to signal the end of such a sequence. Example:
  35  *
  36  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  37  *
  38  * Unicode in PS1 is not fully supported: prompt length calulation is wrong,
  39  * resulting in line wrap problems with long (multi-line) input.
  40  */
  41 #include "busybox.h"
  42 #include "NUM_APPLETS.h"
  43 #include "unicode.h"
  44 #if ENABLE_ASH_EMBEDDED_SCRIPTS
  45 # include "embedded_scripts.h"
  46 #else
  47 # define NUM_SCRIPTS 0
  48 #endif
  49
  50 #ifndef _POSIX_VDISABLE
  51 # define _POSIX_VDISABLE '\0'
  52 #endif
  53
  54
  55 #ifdef TEST
  56 # define ENABLE_FEATURE_EDITING 0
  57 # define ENABLE_FEATURE_TAB_COMPLETION 0
  58 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  59 #endif
  60
  61
  62 /* Entire file (except TESTing part) sits inside this #if */
  63 #if ENABLE_FEATURE_EDITING
  64
  65
  66 #define ENABLE_USERNAME_OR_HOMEDIR \
  67         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  68 #define IF_USERNAME_OR_HOMEDIR(...)
  69 #if ENABLE_USERNAME_OR_HOMEDIR
  70 # undef IF_USERNAME_OR_HOMEDIR
  71 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  72 #endif
  73
  74
  75 #undef CHAR_T
  76 #if ENABLE_UNICODE_SUPPORT
  77 # define BB_NUL ((wchar_t)0)
  78 # define CHAR_T wchar_t
  79 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  80 # if ENABLE_FEATURE_EDITING_VI
  81 static bool BB_isalnum_or_underscore(CHAR_T c) {
  82         return ((unsigned)c < 256 && isalnum(c)) || c == '_';
  83 }
  84 # endif
  85 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  86 # undef isspace
  87 # undef isalnum
  88 # undef ispunct
  89 # undef isprint
  90 # define isspace isspace_must_not_be_used
  91 # define isalnum isalnum_must_not_be_used
  92 # define ispunct ispunct_must_not_be_used
  93 # define isprint isprint_must_not_be_used
  94 #else
  95 # define BB_NUL '\0'
  96 # define CHAR_T char
  97 # define BB_isspace(c) isspace(c)
  98 # if ENABLE_FEATURE_EDITING_VI
  99 static bool BB_isalnum_or_underscore(CHAR_T c)
 100 {
 101         return ((unsigned)c < 256 && isalnum(c)) || c == '_';
 102 }
 103 # endif
 104 # define BB_ispunct(c) ispunct(c)
 105 #endif
 106 #if ENABLE_UNICODE_PRESERVE_BROKEN
 107 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
 108 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
 109 #else
 110 # define unicode_is_raw_byte(wc)     0
 111 #endif
 112
 113
 114 #define ESC "\033"
 115
 116 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 117 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 118
 119
 120 enum {
 121         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 122                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 123                       : 0x7ff0
 124 };
 125
 126 #if ENABLE_USERNAME_OR_HOMEDIR
 127 static const char null_str[] ALIGN1 = "";
 128 #endif
 129
 130 /* We try to minimize both static and stack usage. */
 131 struct lineedit_statics {
 132         line_input_t *state;
 133
 134         unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 135
 136         unsigned cmdedit_x;        /* real x (col) terminal position */
 137         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 138         unsigned cmdedit_prmt_len; /* on-screen length of last/sole prompt line */
 139
 140         unsigned cursor;
 141         int command_len; /* must be signed */
 142         /* signed maxsize: we want x in "if (x > S.maxsize)"
 143          * to _not_ be promoted to unsigned */
 144         int maxsize;
 145         CHAR_T *command_ps;
 146
 147         const char *cmdedit_prompt;
 148         const char *prompt_last_line;  /* last/sole prompt line */
 149
 150 #if ENABLE_USERNAME_OR_HOMEDIR
 151         char *user_buf;
 152         char *home_pwd_buf; /* = (char*)null_str; */
 153 #endif
 154
 155 #if ENABLE_FEATURE_TAB_COMPLETION
 156         char **matches;
 157         unsigned num_matches;
 158 #endif
 159
 160 #if ENABLE_FEATURE_EDITING_WINCH
 161         unsigned SIGWINCH_saved;
 162         volatile unsigned SIGWINCH_count;
 163         volatile smallint ok_to_redraw;
 164 #endif
 165
 166 #if ENABLE_FEATURE_EDITING_VI
 167 # define DELBUFSIZ 128
 168         smallint newdelflag;     /* whether delbuf should be reused yet */
 169         CHAR_T *delptr;
 170         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 171 #endif
 172 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 173         smallint sent_ESC_br6n;
 174 #endif
 175
 176 #if ENABLE_FEATURE_EDITING_WINCH
 177         /* Largish struct, keeping it last results in smaller code */
 178         struct sigaction SIGWINCH_handler;
 179 #endif
 180 };
 181
 182 /* See lineedit_ptr_hack.c */
 183 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 184
 185 #define S (*lineedit_ptr_to_statics)
 186 #define state            (S.state           )
 187 #define cmdedit_termw    (S.cmdedit_termw   )
 188 #define cmdedit_x        (S.cmdedit_x       )
 189 #define cmdedit_y        (S.cmdedit_y       )
 190 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 191 #define cursor           (S.cursor          )
 192 #define command_len      (S.command_len     )
 193 #define command_ps       (S.command_ps      )
 194 #define cmdedit_prompt   (S.cmdedit_prompt  )
 195 #define prompt_last_line (S.prompt_last_line)
 196 #define user_buf         (S.user_buf        )
 197 #define home_pwd_buf     (S.home_pwd_buf    )
 198 #define matches          (S.matches         )
 199 #define num_matches      (S.num_matches     )
 200 #define delptr           (S.delptr          )
 201 #define newdelflag       (S.newdelflag      )
 202 #define delbuf           (S.delbuf          )
 203
 204 #define INIT_S() do { \
 205         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 206         barrier(); \
 207         cmdedit_termw = 80; \
 208         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 209         IF_FEATURE_EDITING_VI(delptr = delbuf;) \
 210 } while (0)
 211
 212 static void deinit_S(void)
 213 {
 214 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 215         /* This one is allocated only if FANCY_PROMPT is on
 216          * (otherwise it points to verbatim prompt (NOT malloced)) */
 217         free((char*)cmdedit_prompt);
 218 #endif
 219 #if ENABLE_USERNAME_OR_HOMEDIR
 220         free(user_buf);
 221         if (home_pwd_buf != null_str)
 222                 free(home_pwd_buf);
 223 #endif
 224         free(lineedit_ptr_to_statics);
 225 }
 226 #define DEINIT_S() deinit_S()
 227
 228
 229 #if ENABLE_UNICODE_SUPPORT
 230 static size_t load_string(const char *src)
 231 {
 232         if (unicode_status == UNICODE_ON) {
 233                 ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
 234                 if (len < 0)
 235                         len = 0;
 236                 command_ps[len] = BB_NUL;
 237                 return len;
 238         } else {
 239                 unsigned i = 0;
 240                 while (src[i] && i < S.maxsize - 1) {
 241                         command_ps[i] = src[i];
 242                         i++;
 243                 }
 244                 command_ps[i] = BB_NUL;
 245                 return i;
 246         }
 247 }
 248 static unsigned save_string(char *dst, unsigned maxsize)
 249 {
 250         if (unicode_status == UNICODE_ON) {
 251 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 252                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 253                 if (len < 0)
 254                         len = 0;
 255                 dst[len] = '\0';
 256                 return len;
 257 # else
 258                 unsigned dstpos = 0;
 259                 unsigned srcpos = 0;
 260
 261                 maxsize--;
 262                 while (dstpos < maxsize) {
 263                         wchar_t wc;
 264                         int n = srcpos;
 265
 266                         /* Convert up to 1st invalid byte (or up to end) */
 267                         while ((wc = command_ps[srcpos]) != BB_NUL
 268                             && !unicode_is_raw_byte(wc)
 269                         ) {
 270                                 srcpos++;
 271                         }
 272                         command_ps[srcpos] = BB_NUL;
 273                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 274                         if (n < 0) /* should not happen */
 275                                 break;
 276                         dstpos += n;
 277                         if (wc == BB_NUL) /* usually is */
 278                                 break;
 279
 280                         /* We do have invalid byte here! */
 281                         command_ps[srcpos] = wc; /* restore it */
 282                         srcpos++;
 283                         if (dstpos == maxsize)
 284                                 break;
 285                         dst[dstpos++] = (char) wc;
 286                 }
 287                 dst[dstpos] = '\0';
 288                 return dstpos;
 289 # endif
 290         } else {
 291                 unsigned i = 0;
 292                 while ((dst[i] = command_ps[i]) != 0)
 293                         i++;
 294                 return i;
 295         }
 296 }
 297 /* I thought just fputwc(c, stdout) would work. But no... */
 298 static void BB_PUTCHAR(wchar_t c)
 299 {
 300         if (unicode_status == UNICODE_ON) {
 301                 char buf[MB_CUR_MAX + 1];
 302                 mbstate_t mbst = { 0 };
 303                 ssize_t len = wcrtomb(buf, c, &mbst);
 304                 if (len > 0) {
 305                         buf[len] = '\0';
 306                         fputs(buf, stdout);
 307                 }
 308         } else {
 309                 /* In this case, c is always one byte */
 310                 putchar(c);
 311         }
 312 }
 313 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 314 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 315 # else
 316 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 317 #  define adjust_width_and_validate_wc(width_adj, wc) \
 318         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 319 # endif
 320 {
 321         int w = 1;
 322
 323         if (unicode_status == UNICODE_ON) {
 324                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 325                         /* note: also true for unicode_is_raw_byte(wc) */
 326                         goto subst;
 327                 }
 328                 w = wcwidth(wc);
 329                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 330                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 331                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 332                 ) {
 333  subst:
 334                         w = 1;
 335                         wc = CONFIG_SUBST_WCHAR;
 336                 }
 337         }
 338
 339 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 340         *width_adj += w;
 341 #endif
 342         return wc;
 343 }
 344 #else /* !UNICODE */
 345 static size_t load_string(const char *src)
 346 {
 347         safe_strncpy(command_ps, src, S.maxsize);
 348         return strlen(command_ps);
 349 }
 350 # if ENABLE_FEATURE_TAB_COMPLETION
 351 static void save_string(char *dst, unsigned maxsize)
 352 {
 353         safe_strncpy(dst, command_ps, maxsize);
 354 }
 355 # endif
 356 # define BB_PUTCHAR(c) bb_putchar(c)
 357 /* Should never be called: */
 358 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 359 #endif
 360
 361
 362 /* Put 'command_ps[cursor]', cursor++.
 363  * Advance cursor on screen. If we reached right margin, scroll text up
 364  * and remove terminal margin effect by printing 'next_char' */
 365 #define HACK_FOR_WRONG_WIDTH 1
 366 static void put_cur_glyph_and_inc_cursor(void)
 367 {
 368         CHAR_T c = command_ps[cursor];
 369         unsigned width = 0;
 370         int ofs_to_right;
 371
 372         if (c == BB_NUL) {
 373                 /* erase character after end of input string */
 374                 c = ' ';
 375         } else {
 376                 /* advance cursor only if we aren't at the end yet */
 377                 cursor++;
 378                 if (unicode_status == UNICODE_ON) {
 379                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 380                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 381                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 382                 } else {
 383                         cmdedit_x++;
 384                 }
 385         }
 386
 387         ofs_to_right = cmdedit_x - cmdedit_termw;
 388         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 389                 /* c fits on this line */
 390                 BB_PUTCHAR(c);
 391         }
 392
 393         if (ofs_to_right >= 0) {
 394                 /* we go to the next line */
 395 #if HACK_FOR_WRONG_WIDTH
 396                 /* This works better if our idea of term width is wrong
 397                  * and it is actually wider (often happens on serial lines).
 398                  * Printing CR,LF *forces* cursor to next line.
 399                  * OTOH if terminal width is correct AND terminal does NOT
 400                  * have automargin (IOW: it is moving cursor to next line
 401                  * by itself (which is wrong for VT-10x terminals)),
 402                  * this will break things: there will be one extra empty line */
 403                 puts("\r"); /* + implicit '\n' */
 404 #else
 405                 /* VT-10x terminals don't wrap cursor to next line when last char
 406                  * on the line is printed - cursor stays "over" this char.
 407                  * Need to print _next_ char too (first one to appear on next line)
 408                  * to make cursor move down to next line.
 409                  */
 410                 /* Works ok only if cmdedit_termw is correct. */
 411                 c = command_ps[cursor];
 412                 if (c == BB_NUL)
 413                         c = ' ';
 414                 BB_PUTCHAR(c);
 415                 bb_putchar('\b');
 416 #endif
 417                 cmdedit_y++;
 418                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 419                         width = 0;
 420                 } else { /* ofs_to_right > 0 */
 421                         /* wide char c didn't fit on prev line */
 422                         BB_PUTCHAR(c);
 423                 }
 424                 cmdedit_x = width;
 425         }
 426 }
 427
 428 /* Move to end of line (by printing all chars till the end) */
 429 static void put_till_end_and_adv_cursor(void)
 430 {
 431         while (cursor < command_len)
 432                 put_cur_glyph_and_inc_cursor();
 433 }
 434
 435 /* Go to the next line */
 436 static void goto_new_line(void)
 437 {
 438         put_till_end_and_adv_cursor();
 439         /* "cursor == 0" is only if prompt is "" and user input is empty */
 440         if (cursor == 0 || cmdedit_x != 0)
 441                 bb_putchar('\n');
 442 }
 443
 444 static void beep(void)
 445 {
 446         bb_putchar('\007');
 447 }
 448
 449 /* Full or last/sole prompt line, reset edit cursor, calculate terminal cursor.
 450  * cmdedit_y is always calculated for the last/sole prompt line.
 451  */
 452 static void put_prompt_custom(bool is_full)
 453 {
 454         fputs((is_full ? cmdedit_prompt : prompt_last_line), stdout);
 455         cursor = 0;
 456         cmdedit_y = cmdedit_prmt_len / cmdedit_termw; /* new quasireal y */
 457         cmdedit_x = cmdedit_prmt_len % cmdedit_termw;
 458 }
 459
 460 #define put_prompt_last_line() put_prompt_custom(0)
 461 #define put_prompt()           put_prompt_custom(1)
 462
 463 /* Move back one character */
 464 /* (optimized for slow terminals) */
 465 static void input_backward(unsigned num)
 466 {
 467         if (num > cursor)
 468                 num = cursor;
 469         if (num == 0)
 470                 return;
 471         cursor -= num;
 472
 473         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 474          && unicode_status == UNICODE_ON
 475         ) {
 476                 /* correct NUM to be equal to _screen_ width */
 477                 int n = num;
 478                 num = 0;
 479                 while (--n >= 0)
 480                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 481                 if (num == 0)
 482                         return;
 483         }
 484
 485         if (cmdedit_x >= num) {
 486                 cmdedit_x -= num;
 487                 if (num <= 4) {
 488                         /* This is longer by 5 bytes on x86.
 489                          * Also gets miscompiled for ARM users
 490                          * (busybox.net/bugs/view.php?id=2274).
 491                          * printf(("\b\b\b\b" + 4) - num);
 492                          * return;
 493                          */
 494                         do {
 495                                 bb_putchar('\b');
 496                         } while (--num);
 497                         return;
 498                 }
 499                 printf(ESC"[%uD", num);
 500                 return;
 501         }
 502
 503         /* Need to go one or more lines up */
 504         if (ENABLE_UNICODE_WIDE_WCHARS) {
 505                 /* With wide chars, it is hard to "backtrack"
 506                  * and reliably figure out where to put cursor.
 507                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 508                  * |prompt: <><> |
 509                  * |<><><><><><> |
 510                  * |_            |
 511                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 512                  * We need to go up one line, and then - how do we know that
 513                  * we need to go *10* positions to the right? Because
 514                  * |prompt: <>#<>|
 515                  * |<><><>#<><><>|
 516                  * |_            |
 517                  * in this situation we need to go *11* positions to the right.
 518                  *
 519                  * A simpler thing to do is to redraw everything from the start
 520                  * up to new cursor position (which is already known):
 521                  */
 522                 unsigned sv_cursor;
 523                 /* go to 1st column; go up to first line */
 524                 printf("\r" ESC"[%uA", cmdedit_y);
 525                 cmdedit_y = 0;
 526                 sv_cursor = cursor;
 527                 put_prompt_last_line(); /* sets cursor to 0 */
 528                 while (cursor < sv_cursor)
 529                         put_cur_glyph_and_inc_cursor();
 530         } else {
 531                 int lines_up;
 532                 /* num = chars to go back from the beginning of current line: */
 533                 num -= cmdedit_x;
 534                 /* num=1...w: one line up, w+1...2w: two, etc: */
 535                 lines_up = 1 + (num - 1) / cmdedit_termw;
 536                 cmdedit_x = (cmdedit_termw * cmdedit_y - num) % cmdedit_termw;
 537                 cmdedit_y -= lines_up;
 538                 /* go to 1st column; go up */
 539                 printf("\r" ESC"[%uA", lines_up);
 540                 /* go to correct column.
 541                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 542                  * need to *make sure* we skip it if cmdedit_x == 0 */
 543                 if (cmdedit_x)
 544                         printf(ESC"[%uC", cmdedit_x);
 545         }
 546 }
 547
 548 /* See redraw and draw_full below */
 549 static void draw_custom(int y, int back_cursor, bool is_full)
 550 {
 551         if (y > 0) /* up y lines */
 552                 printf(ESC"[%uA", y);
 553         bb_putchar('\r');
 554         put_prompt_custom(is_full);
 555         put_till_end_and_adv_cursor();
 556         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 557         input_backward(back_cursor);
 558 }
 559
 560 /* Move y lines up, draw last/sole prompt line, editor line[s], and clear tail.
 561  * goal: redraw the prompt+input+cursor in-place, overwriting the previous */
 562 #define redraw(y, back_cursor) draw_custom((y), (back_cursor), 0)
 563
 564 /* Like above, but without moving up, and while using all the prompt lines.
 565  * goal: draw a full prompt+input+cursor unrelated to a previous position.
 566  * note: cmdedit_y always ends up relating to the last/sole prompt line */
 567 #define draw_full(back_cursor) draw_custom(0, (back_cursor), 1)
 568
 569 /* Delete the char in front of the cursor, optionally saving it
 570  * for later putback */
 571 #if !ENABLE_FEATURE_EDITING_VI
 572 static void input_delete(void)
 573 #define input_delete(save) input_delete()
 574 #else
 575 static void input_delete(int save)
 576 #endif
 577 {
 578         int j = cursor;
 579
 580         if (j == (int)command_len)
 581                 return;
 582
 583 #if ENABLE_FEATURE_EDITING_VI
 584         if (save) {
 585                 if (newdelflag) {
 586                         delptr = delbuf;
 587                         newdelflag = 0;
 588                 }
 589                 if ((delptr - delbuf) < DELBUFSIZ)
 590                         *delptr++ = command_ps[j];
 591         }
 592 #endif
 593
 594         memmove(command_ps + j, command_ps + j + 1,
 595                         /* (command_len + 1 [because of NUL]) - (j + 1)
 596                          * simplified into (command_len - j) */
 597                         (command_len - j) * sizeof(command_ps[0]));
 598         command_len--;
 599         put_till_end_and_adv_cursor();
 600         /* Last char is still visible, erase it (and more) */
 601         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 602         input_backward(cursor - j);     /* back to old pos cursor */
 603 }
 604
 605 #if ENABLE_FEATURE_EDITING_VI
 606 static void put(void)
 607 {
 608         int ocursor;
 609         int j = delptr - delbuf;
 610
 611         if (j == 0)
 612                 return;
 613         ocursor = cursor;
 614         /* open hole and then fill it */
 615         memmove(command_ps + cursor + j, command_ps + cursor,
 616                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 617         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 618         command_len += j;
 619         put_till_end_and_adv_cursor();
 620         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 621 }
 622 #endif
 623
 624 /* Delete the char in back of the cursor */
 625 static void input_backspace(void)
 626 {
 627         if (cursor > 0) {
 628                 input_backward(1);
 629                 input_delete(0);
 630         }
 631 }
 632
 633 /* Move forward one character */
 634 static void input_forward(void)
 635 {
 636         if (cursor < command_len)
 637                 put_cur_glyph_and_inc_cursor();
 638 }
 639
 640 #if ENABLE_FEATURE_TAB_COMPLETION
 641
 642 //FIXME:
 643 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 644 //matches the file named "foo bar", which is untrue.
 645 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 646 //not "foo bar <cursor>...
 647
 648 static void free_tab_completion_data(void)
 649 {
 650         if (matches) {
 651                 while (num_matches)
 652                         free(matches[--num_matches]);
 653                 free(matches);
 654                 matches = NULL;
 655         }
 656 }
 657
 658 static void add_match(char *matched)
 659 {
 660         unsigned char *p = (unsigned char*)matched;
 661         while (*p) {
 662                 /* ESC attack fix: drop any string with control chars */
 663                 if (*p < ' '
 664                  || (!ENABLE_UNICODE_SUPPORT && *p >= 0x7f)
 665                  || (ENABLE_UNICODE_SUPPORT && *p == 0x7f)
 666                 ) {
 667                         free(matched);
 668                         return;
 669                 }
 670                 p++;
 671         }
 672         matches = xrealloc_vector(matches, 4, num_matches);
 673         matches[num_matches] = matched;
 674         num_matches++;
 675 }
 676
 677 # if ENABLE_FEATURE_USERNAME_COMPLETION
 678 /* Replace "~user/..." with "/homedir/...".
 679  * The parameter is malloced, free it or return it
 680  * unchanged if no user is matched.
 681  */
 682 static char *username_path_completion(char *ud)
 683 {
 684         struct passwd *entry;
 685         char *tilde_name = ud;
 686         char *home = NULL;
 687
 688         ud++; /* skip ~ */
 689         if (*ud == '/') {       /* "~/..." */
 690                 home = home_pwd_buf;
 691         } else {
 692                 /* "~user/..." */
 693                 ud = strchr(ud, '/');
 694                 *ud = '\0';           /* "~user" */
 695                 entry = getpwnam(tilde_name + 1);
 696                 *ud = '/';            /* restore "~user/..." */
 697                 if (entry)
 698                         home = entry->pw_dir;
 699         }
 700         if (home) {
 701                 ud = concat_path_file(home, ud);
 702                 free(tilde_name);
 703                 tilde_name = ud;
 704         }
 705         return tilde_name;
 706 }
 707
 708 /* ~use<tab> - find all users with this prefix.
 709  * Return the length of the prefix used for matching.
 710  */
 711 static NOINLINE unsigned complete_username(const char *ud)
 712 {
 713         struct passwd *pw;
 714         unsigned userlen;
 715
 716         ud++; /* skip ~ */
 717         userlen = strlen(ud);
 718
 719         setpwent();
 720         while ((pw = getpwent()) != NULL) {
 721                 /* Null usernames should result in all users as possible completions. */
 722                 if (/* !ud[0] || */ is_prefixed_with(pw->pw_name, ud)) {
 723                         add_match(xasprintf("~%s/", pw->pw_name));
 724                 }
 725         }
 726         endpwent(); /* don't keep password file open */
 727
 728         return 1 + userlen;
 729 }
 730 # endif  /* FEATURE_USERNAME_COMPLETION */
 731
 732 enum {
 733         FIND_EXE_ONLY = 0,
 734         FIND_DIR_ONLY = 1,
 735         FIND_FILE_ONLY = 2,
 736 };
 737
 738 static int path_parse(char ***p)
 739 {
 740         int npth;
 741         const char *pth;
 742         char *tmp;
 743         char **res;
 744
 745         if (state->flags & WITH_PATH_LOOKUP)
 746                 pth = state->path_lookup;
 747         else
 748                 pth = getenv("PATH");
 749
 750         /* PATH="" or PATH=":"? */
 751         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 752                 return 1;
 753
 754         tmp = (char*)pth;
 755         npth = 1; /* path component count */
 756         while (1) {
 757                 tmp = strchr(tmp, ':');
 758                 if (!tmp)
 759                         break;
 760                 tmp++;
 761                 if (*tmp == '\0')
 762                         break;  /* :<empty> */
 763                 npth++;
 764         }
 765
 766         *p = res = xmalloc(npth * sizeof(res[0]));
 767         res[0] = tmp = xstrdup(pth);
 768         npth = 1;
 769         while (1) {
 770                 tmp = strchr(tmp, ':');
 771                 if (!tmp)
 772                         break;
 773                 *tmp++ = '\0'; /* ':' -> '\0' */
 774                 if (*tmp == '\0')
 775                         break; /* :<empty> */
 776                 res[npth++] = tmp;
 777         }
 778         return npth;
 779 }
 780
 781 /* Complete command, directory or file name.
 782  * Return the length of the prefix used for matching.
 783  */
 784 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 785 {
 786         char *path1[1];
 787         char **paths = path1;
 788         int npaths;
 789         int i;
 790         unsigned pf_len;
 791         const char *pfind;
 792         char *dirbuf = NULL;
 793
 794         npaths = 1;
 795         path1[0] = (char*)".";
 796
 797         pfind = strrchr(command, '/');
 798         if (!pfind) {
 799                 if (type == FIND_EXE_ONLY)
 800                         npaths = path_parse(&paths);
 801                 pfind = command;
 802         } else {
 803                 /* point to 'l' in "..../last_component" */
 804                 pfind++;
 805                 /* dirbuf = ".../.../.../" */
 806                 dirbuf = xstrndup(command, pfind - command);
 807 # if ENABLE_FEATURE_USERNAME_COMPLETION
 808                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 809                         dirbuf = username_path_completion(dirbuf);
 810 # endif
 811                 path1[0] = dirbuf;
 812         }
 813         pf_len = strlen(pfind);
 814
 815 # if ENABLE_FEATURE_SH_STANDALONE && (NUM_APPLETS != 1 || NUM_SCRIPTS > 0)
 816         if (type == FIND_EXE_ONLY && !dirbuf) {
 817                 const char *p;
 818 #  if NUM_APPLETS != 1 && NUM_SCRIPTS > 0
 819                 for (i = 0, p = applet_names; i < 2; i++, p = script_names)
 820 #  elif NUM_APPLETS != 1 /* and NUM_SCRIPTS == 0 */
 821                 p = applet_names;
 822 #  else /* NUM_APPLETS == 1 && NUM_SCRIPTS > 0 */
 823                 p = script_names;
 824 #  endif
 825                 while (*p) {
 826                         if (strncmp(pfind, p, pf_len) == 0)
 827                                 add_match(xstrdup(p));
 828                         while (*p++)
 829                                 continue;
 830                 }
 831         }
 832 # endif
 833
 834         for (i = 0; i < npaths; i++) {
 835                 DIR *dir;
 836                 struct dirent *next;
 837                 struct stat st;
 838                 char *found;
 839
 840                 dir = opendir(paths[i]);
 841                 if (!dir)
 842                         continue; /* don't print an error */
 843
 844                 while ((next = readdir(dir)) != NULL) {
 845                         unsigned len;
 846                         const char *name_found = next->d_name;
 847
 848                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 849                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 850                                 continue;
 851                         /* match? */
 852                         if (!is_prefixed_with(name_found, pfind))
 853                                 continue; /* no */
 854
 855                         found = concat_path_file(paths[i], name_found);
 856                         /* NB: stat() first so that we see is it a directory;
 857                          * but if that fails, use lstat() so that
 858                          * we still match dangling links */
 859                         if (stat(found, &st) && lstat(found, &st))
 860                                 goto cont; /* hmm, remove in progress? */
 861
 862                         /* Save only name */
 863                         len = strlen(name_found);
 864                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 865                         strcpy(found, name_found);
 866
 867                         if (S_ISDIR(st.st_mode)) {
 868                                 /* name is a directory, add slash */
 869                                 found[len] = '/';
 870                                 found[len + 1] = '\0';
 871                         } else {
 872                                 /* skip files if looking for dirs only (example: cd) */
 873                                 if (type == FIND_DIR_ONLY)
 874                                         goto cont;
 875                         }
 876                         /* add it to the list */
 877                         add_match(found);
 878                         continue;
 879  cont:
 880                         free(found);
 881                 }
 882                 closedir(dir);
 883         } /* for every path */
 884
 885         if (paths != path1) {
 886                 free(paths[0]); /* allocated memory is only in first member */
 887                 free(paths);
 888         }
 889         free(dirbuf);
 890
 891         return pf_len;
 892 }
 893
 894 /* build_match_prefix:
 895  * On entry, match_buf contains everything up to cursor at the moment <tab>
 896  * was pressed. This function looks at it, figures out what part of it
 897  * constitutes the command/file/directory prefix to use for completion,
 898  * and rewrites match_buf to contain only that part.
 899  */
 900 #define dbg_bmp 0
 901 /* Helpers: */
 902 /* QUOT is used on elements of int_buf[], which are bytes,
 903  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 904  */
 905 #define QUOT (UCHAR_MAX+1)
 906 static void remove_chunk(int16_t *int_buf, int beg, int end)
 907 {
 908         /* beg must be <= end */
 909         if (beg == end)
 910                 return;
 911
 912         while ((int_buf[beg] = int_buf[end]) != 0)
 913                 beg++, end++;
 914
 915         if (dbg_bmp) {
 916                 int i;
 917                 for (i = 0; int_buf[i]; i++)
 918                         bb_putchar((unsigned char)int_buf[i]);
 919                 bb_putchar('\n');
 920         }
 921 }
 922 /* Caller ensures that match_buf points to a malloced buffer
 923  * big enough to hold strlen(match_buf)*2 + 2
 924  */
 925 static NOINLINE int build_match_prefix(char *match_buf)
 926 {
 927         int i, j;
 928         int command_mode;
 929         int16_t *int_buf = (int16_t*)match_buf;
 930
 931         if (dbg_bmp) printf("\n%s\n", match_buf);
 932
 933         /* Copy in reverse order, since they overlap */
 934         i = strlen(match_buf);
 935         do {
 936                 int_buf[i] = (unsigned char)match_buf[i];
 937                 i--;
 938         } while (i >= 0);
 939
 940         /* Mark every \c as "quoted c" */
 941         for (i = 0; int_buf[i]; i++) {
 942                 if (int_buf[i] == '\\') {
 943                         remove_chunk(int_buf, i, i + 1);
 944                         int_buf[i] |= QUOT;
 945                 }
 946         }
 947         /* Quote-mark "chars" and 'chars', drop delimiters */
 948         {
 949                 int in_quote = 0;
 950                 i = 0;
 951                 while (int_buf[i]) {
 952                         int cur = int_buf[i];
 953                         if (!cur)
 954                                 break;
 955                         if (cur == '\'' || cur == '"') {
 956                                 if (!in_quote || (cur == in_quote)) {
 957                                         in_quote ^= cur;
 958                                         remove_chunk(int_buf, i, i + 1);
 959                                         continue;
 960                                 }
 961                         }
 962                         if (in_quote)
 963                                 int_buf[i] = cur | QUOT;
 964                         i++;
 965                 }
 966         }
 967
 968         /* Remove everything up to command delimiters:
 969          * ';' ';;' '&' '|' '&&' '||',
 970          * but careful with '>&' '<&' '>|'
 971          */
 972         for (i = 0; int_buf[i]; i++) {
 973                 int cur = int_buf[i];
 974                 if (cur == ';' || cur == '&' || cur == '|') {
 975                         int prev = i ? int_buf[i - 1] : 0;
 976                         if (cur == '&' && (prev == '>' || prev == '<')) {
 977                                 continue;
 978                         } else if (cur == '|' && prev == '>') {
 979                                 continue;
 980                         }
 981                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 982                         i = -1;  /* back to square 1 */
 983                 }
 984         }
 985         /* Remove all `cmd` */
 986         for (i = 0; int_buf[i]; i++) {
 987                 if (int_buf[i] == '`') {
 988                         for (j = i + 1; int_buf[j]; j++) {
 989                                 if (int_buf[j] == '`') {
 990                                         /* `cmd` should count as a word:
 991                                          * `cmd` c<tab> should search for files c*,
 992                                          * not commands c*. Therefore we don't drop
 993                                          * `cmd` entirely, we replace it with single `.
 994                                          */
 995                                         remove_chunk(int_buf, i, j);
 996                                         goto next;
 997                                 }
 998                         }
 999                         /* No closing ` - command mode, remove all up to ` */
1000                         remove_chunk(int_buf, 0, i + 1);
1001                         break;
1002  next: ;
1003                 }
1004         }
1005
1006         /* Remove "cmd (" and "cmd {"
1007          * Example: "if { c<tab>"
1008          * In this example, c should be matched as command pfx.
1009          */
1010         for (i = 0; int_buf[i]; i++) {
1011                 if (int_buf[i] == '(' || int_buf[i] == '{') {
1012                         remove_chunk(int_buf, 0, i + 1);
1013                         i = -1;  /* back to square 1 */
1014                 }
1015         }
1016
1017         /* Remove leading unquoted spaces */
1018         for (i = 0; int_buf[i]; i++)
1019                 if (int_buf[i] != ' ')
1020                         break;
1021         remove_chunk(int_buf, 0, i);
1022
1023         /* Determine completion mode */
1024         command_mode = FIND_EXE_ONLY;
1025         for (i = 0; int_buf[i]; i++) {
1026                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
1027                         if (int_buf[i] == ' '
1028                          && command_mode == FIND_EXE_ONLY
1029                          && (char)int_buf[0] == 'c'
1030                          && (char)int_buf[1] == 'd'
1031                          && i == 2 /* -> int_buf[2] == ' ' */
1032                         ) {
1033                                 command_mode = FIND_DIR_ONLY;
1034                         } else {
1035                                 command_mode = FIND_FILE_ONLY;
1036                                 break;
1037                         }
1038                 }
1039         }
1040         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
1041
1042         /* Remove everything except last word */
1043         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
1044                 continue;
1045         for (--i; i >= 0; i--) {
1046                 int cur = int_buf[i];
1047                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
1048                         remove_chunk(int_buf, 0, i + 1);
1049                         break;
1050                 }
1051         }
1052
1053         /* Convert back to string of _chars_ */
1054         i = 0;
1055         while ((match_buf[i] = int_buf[i]) != '\0')
1056                 i++;
1057
1058         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
1059
1060         return command_mode;
1061 }
1062
1063 /*
1064  * Display by column (original idea from ls applet,
1065  * very optimized by me [Vladimir] :)
1066  */
1067 static void showfiles(void)
1068 {
1069         int ncols, row;
1070         int column_width = 0;
1071         int nfiles = num_matches;
1072         int nrows = nfiles;
1073         int l;
1074
1075         /* find the longest file name - use that as the column width */
1076         for (row = 0; row < nrows; row++) {
1077                 l = unicode_strwidth(matches[row]);
1078                 if (column_width < l)
1079                         column_width = l;
1080         }
1081         column_width += 2;              /* min space for columns */
1082         ncols = cmdedit_termw / column_width;
1083
1084         if (ncols > 1) {
1085                 nrows /= ncols;
1086                 if (nfiles % ncols)
1087                         nrows++;        /* round up fractionals */
1088         } else {
1089                 ncols = 1;
1090         }
1091         for (row = 0; row < nrows; row++) {
1092                 int n = row;
1093                 int nc;
1094
1095                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1096                         printf("%s%-*s", matches[n],
1097                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1098                         );
1099                 }
1100                 if (ENABLE_UNICODE_SUPPORT)
1101                         puts(printable_string(matches[n]));
1102                 else
1103                         puts(matches[n]);
1104         }
1105 }
1106
1107 static const char *is_special_char(char c)
1108 {
1109         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1110 }
1111
1112 static char *quote_special_chars(char *found)
1113 {
1114         int l = 0;
1115         char *s = xzalloc((strlen(found) + 1) * 2);
1116
1117         while (*found) {
1118                 if (is_special_char(*found))
1119                         s[l++] = '\\';
1120                 s[l++] = *found++;
1121         }
1122         /* s[l] = '\0'; - already is */
1123         return s;
1124 }
1125
1126 /* Do TAB completion */
1127 static NOINLINE void input_tab(smallint *lastWasTab)
1128 {
1129         char *chosen_match;
1130         char *match_buf;
1131         size_t len_found;
1132         /* Length of string used for matching */
1133         unsigned match_pfx_len = match_pfx_len;
1134         int find_type;
1135 # if ENABLE_UNICODE_SUPPORT
1136         /* cursor pos in command converted to multibyte form */
1137         int cursor_mb;
1138 # endif
1139         if (!(state->flags & TAB_COMPLETION))
1140                 return;
1141
1142         if (*lastWasTab) {
1143                 /* The last char was a TAB too.
1144                  * Print a list of all the available choices.
1145                  */
1146                 if (num_matches > 0) {
1147                         /* cursor will be changed by goto_new_line() */
1148                         int sav_cursor = cursor;
1149                         goto_new_line();
1150                         showfiles();
1151                         draw_full(command_len - sav_cursor);
1152                 }
1153                 return;
1154         }
1155
1156         *lastWasTab = 1;
1157         chosen_match = NULL;
1158
1159         /* Make a local copy of the string up to the position of the cursor.
1160          * build_match_prefix will expand it into int16_t's, need to allocate
1161          * twice as much as the string_len+1.
1162          * (we then also (ab)use this extra space later - see (**))
1163          */
1164         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1165 # if !ENABLE_UNICODE_SUPPORT
1166         save_string(match_buf, cursor + 1); /* +1 for NUL */
1167 # else
1168         {
1169                 CHAR_T wc = command_ps[cursor];
1170                 command_ps[cursor] = BB_NUL;
1171                 save_string(match_buf, MAX_LINELEN);
1172                 command_ps[cursor] = wc;
1173                 cursor_mb = strlen(match_buf);
1174         }
1175 # endif
1176         find_type = build_match_prefix(match_buf);
1177
1178         /* Free up any memory already allocated */
1179         free_tab_completion_data();
1180
1181 # if ENABLE_FEATURE_USERNAME_COMPLETION
1182         /* If the word starts with ~ and there is no slash in the word,
1183          * then try completing this word as a username. */
1184         if (state->flags & USERNAME_COMPLETION)
1185                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1186                         match_pfx_len = complete_username(match_buf);
1187 # endif
1188         /* If complete_username() did not match,
1189          * try to match a command in $PATH, or a directory, or a file */
1190         if (!matches)
1191                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1192
1193         /* Account for backslashes which will be inserted
1194          * by quote_special_chars() later */
1195         {
1196                 const char *e = match_buf + strlen(match_buf);
1197                 const char *s = e - match_pfx_len;
1198                 while (s < e)
1199                         if (is_special_char(*s++))
1200                                 match_pfx_len++;
1201         }
1202
1203         /* Remove duplicates */
1204         if (matches) {
1205                 unsigned i, n = 0;
1206                 qsort_string_vector(matches, num_matches);
1207                 for (i = 0; i < num_matches - 1; ++i) {
1208                         //if (matches[i] && matches[i+1]) { /* paranoia */
1209                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1210                                         free(matches[i]);
1211                                         //matches[i] = NULL; /* paranoia */
1212                                 } else {
1213                                         matches[n++] = matches[i];
1214                                 }
1215                         //}
1216                 }
1217                 matches[n++] = matches[i];
1218                 num_matches = n;
1219         }
1220
1221         /* Did we find exactly one match? */
1222         if (num_matches != 1) { /* no */
1223                 char *cp;
1224                 beep();
1225                 if (!matches)
1226                         goto ret; /* no matches at all */
1227                 /* Find common prefix */
1228                 chosen_match = xstrdup(matches[0]);
1229                 for (cp = chosen_match; *cp; cp++) {
1230                         unsigned n;
1231                         for (n = 1; n < num_matches; n++) {
1232                                 if (matches[n][cp - chosen_match] != *cp) {
1233                                         goto stop;
1234                                 }
1235                         }
1236                 }
1237  stop:
1238                 if (cp == chosen_match) { /* have unique prefix? */
1239                         goto ret; /* no */
1240                 }
1241                 *cp = '\0';
1242                 cp = quote_special_chars(chosen_match);
1243                 free(chosen_match);
1244                 chosen_match = cp;
1245                 len_found = strlen(chosen_match);
1246         } else {                        /* exactly one match */
1247                 /* Next <tab> is not a double-tab */
1248                 *lastWasTab = 0;
1249
1250                 chosen_match = quote_special_chars(matches[0]);
1251                 len_found = strlen(chosen_match);
1252                 if (chosen_match[len_found-1] != '/') {
1253                         chosen_match[len_found] = ' ';
1254                         chosen_match[++len_found] = '\0';
1255                 }
1256         }
1257
1258 # if !ENABLE_UNICODE_SUPPORT
1259         /* Have space to place the match? */
1260         /* The result consists of three parts with these lengths: */
1261         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1262         /* it simplifies into: */
1263         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1264                 int pos;
1265                 /* save tail */
1266                 strcpy(match_buf, &command_ps[cursor]);
1267                 /* add match and tail */
1268                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1269                 command_len = strlen(command_ps);
1270                 /* new pos */
1271                 pos = cursor + len_found - match_pfx_len;
1272                 /* write out the matched command */
1273                 redraw(cmdedit_y, command_len - pos);
1274         }
1275 # else
1276         {
1277                 /* Use 2nd half of match_buf as scratch space - see (**) */
1278                 char *command = match_buf + MAX_LINELEN;
1279                 int len = save_string(command, MAX_LINELEN);
1280                 /* Have space to place the match? */
1281                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1282                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1283                         int pos;
1284                         /* save tail */
1285                         strcpy(match_buf, &command[cursor_mb]);
1286                         /* where do we want to have cursor after all? */
1287                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1288                         len = load_string(command);
1289                         /* add match and tail */
1290                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1291                         command_len = load_string(command);
1292                         /* write out the matched command */
1293                         /* paranoia: load_string can return 0 on conv error,
1294                          * prevent passing pos = (0 - 12) to redraw */
1295                         pos = command_len - len;
1296                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1297                 }
1298         }
1299 # endif
1300  ret:
1301         free(chosen_match);
1302         free(match_buf);
1303 }
1304
1305 #endif  /* FEATURE_TAB_COMPLETION */
1306
1307
1308 line_input_t* FAST_FUNC new_line_input_t(int flags)
1309 {
1310         line_input_t *n = xzalloc(sizeof(*n));
1311         n->flags = flags;
1312         n->timeout = -1;
1313 #if MAX_HISTORY > 0
1314         n->max_history = MAX_HISTORY;
1315 #endif
1316         return n;
1317 }
1318
1319
1320 #if MAX_HISTORY > 0
1321
1322 unsigned FAST_FUNC size_from_HISTFILESIZE(const char *hp)
1323 {
1324         int size = MAX_HISTORY;
1325         if (hp) {
1326                 size = atoi(hp);
1327                 if (size <= 0)
1328                         return 1;
1329                 if (size > MAX_HISTORY)
1330                         return MAX_HISTORY;
1331         }
1332         return size;
1333 }
1334
1335 static void save_command_ps_at_cur_history(void)
1336 {
1337         if (command_ps[0] != BB_NUL) {
1338                 int cur = state->cur_history;
1339                 free(state->history[cur]);
1340
1341 # if ENABLE_UNICODE_SUPPORT
1342                 {
1343                         char tbuf[MAX_LINELEN];
1344                         save_string(tbuf, sizeof(tbuf));
1345                         state->history[cur] = xstrdup(tbuf);
1346                 }
1347 # else
1348                 state->history[cur] = xstrdup(command_ps);
1349 # endif
1350         }
1351 }
1352
1353 /* state->flags is already checked to be nonzero */
1354 static int get_previous_history(void)
1355 {
1356         if ((state->flags & DO_HISTORY) && state->cur_history) {
1357                 save_command_ps_at_cur_history();
1358                 state->cur_history--;
1359                 return 1;
1360         }
1361         beep();
1362         return 0;
1363 }
1364
1365 static int get_next_history(void)
1366 {
1367         if (state->flags & DO_HISTORY) {
1368                 if (state->cur_history < state->cnt_history) {
1369                         save_command_ps_at_cur_history(); /* save the current history line */
1370                         return ++state->cur_history;
1371                 }
1372         }
1373         beep();
1374         return 0;
1375 }
1376
1377 /* Lists command history. Used by shell 'history' builtins */
1378 void FAST_FUNC show_history(const line_input_t *st)
1379 {
1380         int i;
1381
1382         if (!st)
1383                 return;
1384         for (i = 0; i < st->cnt_history; i++)
1385                 printf("%4d %s\n", i, st->history[i]);
1386 }
1387
1388 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1389 /* We try to ensure that concurrent additions to the history
1390  * do not overwrite each other.
1391  * Otherwise shell users get unhappy.
1392  *
1393  * History file is trimmed lazily, when it grows several times longer
1394  * than configured MAX_HISTORY lines.
1395  */
1396
1397 static void free_line_input_t(line_input_t *n)
1398 {
1399         int i = n->cnt_history;
1400         while (i > 0)
1401                 free(n->history[--i]);
1402         free(n);
1403 }
1404
1405 /* state->flags is already checked to be nonzero */
1406 static void load_history(line_input_t *st_parm)
1407 {
1408         char *temp_h[MAX_HISTORY];
1409         char *line;
1410         FILE *fp;
1411         unsigned idx, i, line_len;
1412
1413         /* NB: do not trash old history if file can't be opened */
1414
1415         fp = fopen_for_read(st_parm->hist_file);
1416         if (fp) {
1417                 /* clean up old history */
1418                 for (idx = st_parm->cnt_history; idx > 0;) {
1419                         idx--;
1420                         free(st_parm->history[idx]);
1421                         st_parm->history[idx] = NULL;
1422                 }
1423
1424                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1425                 memset(temp_h, 0, sizeof(temp_h));
1426                 idx = 0;
1427                 st_parm->cnt_history_in_file = 0;
1428                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1429                         if (line[0] == '\0') {
1430                                 free(line);
1431                                 continue;
1432                         }
1433                         free(temp_h[idx]);
1434                         temp_h[idx] = line;
1435                         st_parm->cnt_history_in_file++;
1436                         idx++;
1437                         if (idx == st_parm->max_history)
1438                                 idx = 0;
1439                 }
1440                 fclose(fp);
1441
1442                 /* find first non-NULL temp_h[], if any */
1443                 if (st_parm->cnt_history_in_file) {
1444                         while (temp_h[idx] == NULL) {
1445                                 idx++;
1446                                 if (idx == st_parm->max_history)
1447                                         idx = 0;
1448                         }
1449                 }
1450
1451                 /* copy temp_h[] to st_parm->history[] */
1452                 for (i = 0; i < st_parm->max_history;) {
1453                         line = temp_h[idx];
1454                         if (!line)
1455                                 break;
1456                         idx++;
1457                         if (idx == st_parm->max_history)
1458                                 idx = 0;
1459                         line_len = strlen(line);
1460                         if (line_len >= MAX_LINELEN)
1461                                 line[MAX_LINELEN-1] = '\0';
1462                         st_parm->history[i++] = line;
1463                 }
1464                 st_parm->cnt_history = i;
1465                 if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
1466                         st_parm->cnt_history_in_file = i;
1467         }
1468 }
1469
1470 #  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1471 void save_history(line_input_t *st)
1472 {
1473         FILE *fp;
1474
1475         if (!st->hist_file)
1476                 return;
1477         if (st->cnt_history <= st->cnt_history_in_file)
1478                 return;
1479
1480         fp = fopen(st->hist_file, "a");
1481         if (fp) {
1482                 int i, fd;
1483                 char *new_name;
1484                 line_input_t *st_temp;
1485
1486                 for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
1487                         fprintf(fp, "%s\n", st->history[i]);
1488                 fclose(fp);
1489
1490                 /* we may have concurrently written entries from others.
1491                  * load them */
1492                 st_temp = new_line_input_t(st->flags);
1493                 st_temp->hist_file = st->hist_file;
1494                 st_temp->max_history = st->max_history;
1495                 load_history(st_temp);
1496
1497                 /* write out temp file and replace hist_file atomically */
1498                 new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
1499                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1500                 if (fd >= 0) {
1501                         fp = xfdopen_for_write(fd);
1502                         for (i = 0; i < st_temp->cnt_history; i++)
1503                                 fprintf(fp, "%s\n", st_temp->history[i]);
1504                         fclose(fp);
1505                         if (rename(new_name, st->hist_file) == 0)
1506                                 st->cnt_history_in_file = st_temp->cnt_history;
1507                 }
1508                 free(new_name);
1509                 free_line_input_t(st_temp);
1510         }
1511 }
1512 #  else
1513 static void save_history(char *str)
1514 {
1515         int fd;
1516         int len, len2;
1517
1518         if (!state->hist_file)
1519                 return;
1520
1521         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1522         if (fd < 0)
1523                 return;
1524         xlseek(fd, 0, SEEK_END); /* paranoia */
1525         len = strlen(str);
1526         str[len] = '\n'; /* we (try to) do atomic write */
1527         len2 = full_write(fd, str, len + 1);
1528         str[len] = '\0';
1529         close(fd);
1530         if (len2 != len + 1)
1531                 return; /* "wtf?" */
1532
1533         /* did we write so much that history file needs trimming? */
1534         state->cnt_history_in_file++;
1535         if (state->cnt_history_in_file > state->max_history * 4) {
1536                 char *new_name;
1537                 line_input_t *st_temp;
1538
1539                 /* we may have concurrently written entries from others.
1540                  * load them */
1541                 st_temp = new_line_input_t(state->flags);
1542                 st_temp->hist_file = state->hist_file;
1543                 st_temp->max_history = state->max_history;
1544                 load_history(st_temp);
1545
1546                 /* write out temp file and replace hist_file atomically */
1547                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1548                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1549                 if (fd >= 0) {
1550                         FILE *fp;
1551                         int i;
1552
1553                         fp = xfdopen_for_write(fd);
1554                         for (i = 0; i < st_temp->cnt_history; i++)
1555                                 fprintf(fp, "%s\n", st_temp->history[i]);
1556                         fclose(fp);
1557                         if (rename(new_name, state->hist_file) == 0)
1558                                 state->cnt_history_in_file = st_temp->cnt_history;
1559                 }
1560                 free(new_name);
1561                 free_line_input_t(st_temp);
1562         }
1563 }
1564 #  endif
1565 # else
1566 #  define load_history(a) ((void)0)
1567 #  define save_history(a) ((void)0)
1568 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1569
1570 static void remember_in_history(char *str)
1571 {
1572         int i;
1573
1574         if (!(state->flags & DO_HISTORY))
1575                 return;
1576         if (str[0] == '\0')
1577                 return;
1578         i = state->cnt_history;
1579         /* Don't save dupes */
1580         if (i && strcmp(state->history[i-1], str) == 0)
1581                 return;
1582
1583         free(state->history[state->max_history]); /* redundant, paranoia */
1584         state->history[state->max_history] = NULL; /* redundant, paranoia */
1585
1586         /* If history[] is full, remove the oldest command */
1587         /* we need to keep history[state->max_history] empty, hence >=, not > */
1588         if (i >= state->max_history) {
1589                 free(state->history[0]);
1590                 for (i = 0; i < state->max_history-1; i++)
1591                         state->history[i] = state->history[i+1];
1592                 /* i == state->max_history-1 */
1593 # if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1594                 if (state->cnt_history_in_file)
1595                         state->cnt_history_in_file--;
1596 # endif
1597         }
1598         /* i <= state->max_history-1 */
1599         state->history[i++] = xstrdup(str);
1600         /* i <= state->max_history */
1601         state->cur_history = i;
1602         state->cnt_history = i;
1603 # if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1604         save_history(str);
1605 # endif
1606 }
1607
1608 #else /* MAX_HISTORY == 0 */
1609 # define remember_in_history(a) ((void)0)
1610 #endif /* MAX_HISTORY */
1611
1612
1613 #if ENABLE_FEATURE_EDITING_VI
1614 /*
1615  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1616  */
1617 static void
1618 vi_Word_motion(int eat)
1619 {
1620         CHAR_T *command = command_ps;
1621
1622         while (cursor < command_len && !BB_isspace(command[cursor]))
1623                 input_forward();
1624         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1625                 input_forward();
1626 }
1627
1628 static void
1629 vi_word_motion(int eat)
1630 {
1631         CHAR_T *command = command_ps;
1632
1633         if (BB_isalnum_or_underscore(command[cursor])) {
1634                 while (cursor < command_len
1635                  && (BB_isalnum_or_underscore(command[cursor+1]))
1636                 ) {
1637                         input_forward();
1638                 }
1639         } else if (BB_ispunct(command[cursor])) {
1640                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1641                         input_forward();
1642         }
1643
1644         if (cursor < command_len)
1645                 input_forward();
1646
1647         if (eat) {
1648                 while (cursor < command_len && BB_isspace(command[cursor]))
1649                         input_forward();
1650         }
1651 }
1652
1653 static void
1654 vi_End_motion(void)
1655 {
1656         CHAR_T *command = command_ps;
1657
1658         input_forward();
1659         while (cursor < command_len && BB_isspace(command[cursor]))
1660                 input_forward();
1661         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1662                 input_forward();
1663 }
1664
1665 static void
1666 vi_end_motion(void)
1667 {
1668         CHAR_T *command = command_ps;
1669
1670         if (cursor >= command_len-1)
1671                 return;
1672         input_forward();
1673         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1674                 input_forward();
1675         if (cursor >= command_len-1)
1676                 return;
1677         if (BB_isalnum_or_underscore(command[cursor])) {
1678                 while (cursor < command_len-1
1679                  && (BB_isalnum_or_underscore(command[cursor+1]))
1680                 ) {
1681                         input_forward();
1682                 }
1683         } else if (BB_ispunct(command[cursor])) {
1684                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1685                         input_forward();
1686         }
1687 }
1688
1689 static void
1690 vi_Back_motion(void)
1691 {
1692         CHAR_T *command = command_ps;
1693
1694         while (cursor > 0 && BB_isspace(command[cursor-1]))
1695                 input_backward(1);
1696         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1697                 input_backward(1);
1698 }
1699
1700 static void
1701 vi_back_motion(void)
1702 {
1703         CHAR_T *command = command_ps;
1704
1705         if (cursor <= 0)
1706                 return;
1707         input_backward(1);
1708         while (cursor > 0 && BB_isspace(command[cursor]))
1709                 input_backward(1);
1710         if (cursor <= 0)
1711                 return;
1712         if (BB_isalnum_or_underscore(command[cursor])) {
1713                 while (cursor > 0
1714                  && (BB_isalnum_or_underscore(command[cursor-1]))
1715                 ) {
1716                         input_backward(1);
1717                 }
1718         } else if (BB_ispunct(command[cursor])) {
1719                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1720                         input_backward(1);
1721         }
1722 }
1723 #endif
1724
1725 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1726 static void ctrl_left(void)
1727 {
1728         CHAR_T *command = command_ps;
1729
1730         while (1) {
1731                 CHAR_T c;
1732
1733                 input_backward(1);
1734                 if (cursor == 0)
1735                         break;
1736                 c = command[cursor];
1737                 if (c != ' ' && !BB_ispunct(c)) {
1738                         /* we reached a "word" delimited by spaces/punct.
1739                          * go to its beginning */
1740                         while (1) {
1741                                 c = command[cursor - 1];
1742                                 if (c == ' ' || BB_ispunct(c))
1743                                         break;
1744                                 input_backward(1);
1745                                 if (cursor == 0)
1746                                         break;
1747                         }
1748                         break;
1749                 }
1750         }
1751 }
1752 static void ctrl_right(void)
1753 {
1754         CHAR_T *command = command_ps;
1755
1756         while (1) {
1757                 CHAR_T c;
1758
1759                 c = command[cursor];
1760                 if (c == BB_NUL)
1761                         break;
1762                 if (c != ' ' && !BB_ispunct(c)) {
1763                         /* we reached a "word" delimited by spaces/punct.
1764                          * go to its end + 1 */
1765                         while (1) {
1766                                 input_forward();
1767                                 c = command[cursor];
1768                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1769                                         break;
1770                         }
1771                         break;
1772                 }
1773                 input_forward();
1774         }
1775 }
1776
1777
1778 /*
1779  * read_line_input and its helpers
1780  */
1781
1782 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1783 static void ask_terminal(void)
1784 {
1785         /* Ask terminal where is the cursor now.
1786          * lineedit_read_key handles response and corrects
1787          * our idea of current cursor position.
1788          * Testcase: run "echo -n long_line_long_line_long_line",
1789          * then type in a long, wrapping command and try to
1790          * delete it using backspace key.
1791          * Note: we print it _after_ prompt, because
1792          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1793          */
1794         /* Problem: if there is buffered input on stdin,
1795          * the response will be delivered later,
1796          * possibly to an unsuspecting application.
1797          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1798          * Result:
1799          * ~/srcdevel/bbox/fix/busybox.t4 #
1800          * ~/srcdevel/bbox/fix/busybox.t4 #
1801          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1802          * ~/srcdevel/bbox/fix/busybox.t4 #
1803          *
1804          * Checking for input with poll only makes the race narrower,
1805          * I still can trigger it. Strace:
1806          *
1807          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1808          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1809          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1810          * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
1811          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1812          */
1813         struct pollfd pfd;
1814
1815         pfd.fd = STDIN_FILENO;
1816         pfd.events = POLLIN;
1817         if (safe_poll(&pfd, 1, 0) == 0) {
1818                 S.sent_ESC_br6n = 1;
1819                 fputs(ESC"[6n", stdout);
1820                 fflush_all(); /* make terminal see it ASAP! */
1821         }
1822 }
1823 #else
1824 #define ask_terminal() ((void)0)
1825 #endif
1826
1827 /* Note about multi-line PS1 (e.g. "\n\w \u@\h\n> ") and prompt redrawing:
1828  *
1829  * If the prompt has any newlines, after we print it once we use only its last
1830  * line to redraw in-place, which makes it simpler to calculate how many lines
1831  * we should move the cursor up to align the redraw (cmdedit_y). The earlier
1832  * prompt lines just stay on screen and we redraw below them.
1833  *
1834  * Use cases for all prompt lines beyond the initial draw:
1835  * - After clear-screen (^L) or after displaying tab-completion choices, we
1836  *   print the full prompt, as it isn't redrawn in-place.
1837  * - During terminal resize we could try to redraw all lines, but we don't,
1838  *   because it requires delicate alignment, it's good enough with only the
1839  *   last line, and doing it wrong is arguably worse than not doing it at all.
1840  *
1841  * Terminology wise, if it doesn't mention "full", then it means the last/sole
1842  * prompt line. We use the prompt (last/sole line) while redrawing in-place,
1843  * and the full where we need a fresh one unrelated to an earlier position.
1844  *
1845  * If PS1 is not multiline, the last/sole line and the full are the same string.
1846  */
1847
1848 /* Called just once at read_line_input() init time */
1849 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1850 static void parse_and_put_prompt(const char *prmt_ptr)
1851 {
1852         const char *p;
1853         cmdedit_prompt = prompt_last_line = prmt_ptr;
1854         p = strrchr(prmt_ptr, '\n');
1855         if (p)
1856                 prompt_last_line = p + 1;
1857         cmdedit_prmt_len = unicode_strwidth(prompt_last_line);
1858         put_prompt();
1859 }
1860 #else
1861 static void parse_and_put_prompt(const char *prmt_ptr)
1862 {
1863         int prmt_size = 0;
1864         char *prmt_mem_ptr = xzalloc(1);
1865 # if ENABLE_USERNAME_OR_HOMEDIR
1866         char *cwd_buf = NULL;
1867 # endif
1868         char flg_not_length = '[';
1869         char cbuf[2];
1870
1871         /*cmdedit_prmt_len = 0; - already is */
1872
1873         cbuf[1] = '\0'; /* never changes */
1874
1875         while (*prmt_ptr) {
1876                 char timebuf[sizeof("HH:MM:SS")];
1877                 char *free_me = NULL;
1878                 char *pbuf;
1879                 char c;
1880
1881                 pbuf = cbuf;
1882                 c = *prmt_ptr++;
1883                 if (c == '\\') {
1884                         const char *cp;
1885                         int l;
1886 /*
1887  * Supported via bb_process_escape_sequence:
1888  * \a   ASCII bell character (07)
1889  * \e   ASCII escape character (033)
1890  * \n   newline
1891  * \r   carriage return
1892  * \\   backslash
1893  * \nnn char with octal code nnn
1894  * Supported:
1895  * \$   if the effective UID is 0, a #, otherwise a $
1896  * \w   current working directory, with $HOME abbreviated with a tilde
1897  *      Note: we do not support $PROMPT_DIRTRIM=n feature
1898  * \W   basename of the current working directory, with $HOME abbreviated with a tilde
1899  * \h   hostname up to the first '.'
1900  * \H   hostname
1901  * \u   username
1902  * \[   begin a sequence of non-printing characters
1903  * \]   end a sequence of non-printing characters
1904  * \T   current time in 12-hour HH:MM:SS format
1905  * \@   current time in 12-hour am/pm format
1906  * \A   current time in 24-hour HH:MM format
1907  * \t   current time in 24-hour HH:MM:SS format
1908  *      (all of the above work as \A)
1909  * Not supported:
1910  * \!   history number of this command
1911  * \#   command number of this command
1912  * \j   number of jobs currently managed by the shell
1913  * \l   basename of the shell's terminal device name
1914  * \s   name of the shell, the basename of $0 (the portion following the final slash)
1915  * \V   release of bash, version + patch level (e.g., 2.00.0)
1916  * \d   date in "Weekday Month Date" format (e.g., "Tue May 26")
1917  * \D{format}
1918  *      format is passed to strftime(3).
1919  *      An empty format results in a locale-specific time representation.
1920  *      The braces are required.
1921  * Mishandled by bb_process_escape_sequence:
1922  * \v   version of bash (e.g., 2.00)
1923  */
1924                         cp = prmt_ptr;
1925                         c = *cp;
1926                         if (c != 't') /* don't treat \t as tab */
1927                                 c = bb_process_escape_sequence(&prmt_ptr);
1928                         if (prmt_ptr == cp) {
1929                                 if (*cp == '\0')
1930                                         break;
1931                                 c = *prmt_ptr++;
1932
1933                                 switch (c) {
1934 # if ENABLE_USERNAME_OR_HOMEDIR
1935                                 case 'u':
1936                                         pbuf = user_buf ? user_buf : (char*)"";
1937                                         break;
1938 # endif
1939                                 case 'H':
1940                                 case 'h':
1941                                         pbuf = free_me = safe_gethostname();
1942                                         if (c == 'h')
1943                                                 strchrnul(pbuf, '.')[0] = '\0';
1944                                         break;
1945                                 case '$':
1946                                         c = (geteuid() == 0 ? '#' : '$');
1947                                         break;
1948                                 case 'T': /* 12-hour HH:MM:SS format */
1949                                 case '@': /* 12-hour am/pm format */
1950                                 case 'A': /* 24-hour HH:MM format */
1951                                 case 't': /* 24-hour HH:MM:SS format */
1952                                         /* We show all of them as 24-hour HH:MM */
1953                                         strftime_HHMMSS(timebuf, sizeof(timebuf), NULL)[-3] = '\0';
1954                                         pbuf = timebuf;
1955                                         break;
1956 # if ENABLE_USERNAME_OR_HOMEDIR
1957                                 case 'w': /* current dir */
1958                                 case 'W': /* basename of cur dir */
1959                                         if (!cwd_buf) {
1960                                                 cwd_buf = xrealloc_getcwd_or_warn(NULL);
1961                                                 if (!cwd_buf)
1962                                                         cwd_buf = (char *)bb_msg_unknown;
1963                                                 else if (home_pwd_buf[0]) {
1964                                                         char *after_home_user;
1965
1966                                                         /* /home/user[/something] -> ~[/something] */
1967                                                         after_home_user = is_prefixed_with(cwd_buf, home_pwd_buf);
1968                                                         if (after_home_user
1969                                                          && (*after_home_user == '/' || *after_home_user == '\0')
1970                                                         ) {
1971                                                                 cwd_buf[0] = '~';
1972                                                                 overlapping_strcpy(cwd_buf + 1, after_home_user);
1973                                                         }
1974                                                 }
1975                                         }
1976                                         pbuf = cwd_buf;
1977                                         if (c == 'w')
1978                                                 break;
1979                                         cp = strrchr(pbuf, '/');
1980                                         if (cp)
1981                                                 pbuf = (char*)cp + 1;
1982                                         break;
1983 # endif
1984 // bb_process_escape_sequence does this now:
1985 //                              case 'e': case 'E':     /* \e \E = \033 */
1986 //                                      c = '\033';
1987 //                                      break;
1988                                 case 'x': case 'X': {
1989                                         char buf2[4];
1990                                         for (l = 0; l < 3;) {
1991                                                 unsigned h;
1992                                                 buf2[l++] = *prmt_ptr;
1993                                                 buf2[l] = '\0';
1994                                                 h = strtoul(buf2, &pbuf, 16);
1995                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1996                                                         buf2[--l] = '\0';
1997                                                         break;
1998                                                 }
1999                                                 prmt_ptr++;
2000                                         }
2001                                         c = (char)strtoul(buf2, NULL, 16);
2002                                         if (c == 0)
2003                                                 c = '?';
2004                                         pbuf = cbuf;
2005                                         break;
2006                                 }
2007                                 case '[': case ']':
2008                                         if (c == flg_not_length) {
2009                                                 /* Toggle '['/']' hex 5b/5d */
2010                                                 flg_not_length ^= 6;
2011                                                 continue;
2012                                         }
2013                                         break;
2014                                 } /* switch */
2015                         } /* if */
2016                 } /* if */
2017                 cbuf[0] = c;
2018                 {
2019                         int n = strlen(pbuf);
2020                         prmt_size += n;
2021                         if (c == '\n')
2022                                 cmdedit_prmt_len = 0;
2023                         else if (flg_not_length != ']') {
2024 #if 0 /*ENABLE_UNICODE_SUPPORT*/
2025 /* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
2026 /* FIXME */
2027                                 cmdedit_prmt_len += unicode_strwidth(pbuf);
2028 #else
2029                                 cmdedit_prmt_len += n;
2030 #endif
2031                         }
2032                 }
2033                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_size+1), pbuf);
2034                 free(free_me);
2035         } /* while */
2036
2037 # if ENABLE_USERNAME_OR_HOMEDIR
2038         if (cwd_buf != (char *)bb_msg_unknown)
2039                 free(cwd_buf);
2040 # endif
2041         /* see comment (above this function) about multiline prompt redrawing */
2042         cmdedit_prompt = prompt_last_line = prmt_mem_ptr;
2043         prmt_ptr = strrchr(cmdedit_prompt, '\n');
2044         if (prmt_ptr)
2045                 prompt_last_line = prmt_ptr + 1;
2046         put_prompt();
2047 }
2048 #endif
2049
2050 #if ENABLE_FEATURE_EDITING_WINCH
2051 static void cmdedit_setwidth(void)
2052 {
2053         int new_y;
2054
2055         cmdedit_termw = get_terminal_width(STDIN_FILENO);
2056         /* new y for current cursor */
2057         new_y = (cursor + cmdedit_prmt_len) / cmdedit_termw;
2058         /* redraw */
2059         redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
2060 }
2061
2062 static void win_changed(int nsig UNUSED_PARAM)
2063 {
2064         if (S.ok_to_redraw) {
2065                 /* We are in read_key(), safe to redraw immediately */
2066                 int sv_errno = errno;
2067                 cmdedit_setwidth();
2068                 fflush_all();
2069                 errno = sv_errno;
2070         } else {
2071                 /* Signal main loop that redraw is necessary */
2072                 S.SIGWINCH_count++;
2073         }
2074 }
2075 #endif
2076
2077 static int lineedit_read_key(char *read_key_buffer, int timeout)
2078 {
2079         int64_t ic;
2080 #if ENABLE_UNICODE_SUPPORT
2081         char unicode_buf[MB_CUR_MAX + 1];
2082         int unicode_idx = 0;
2083 #endif
2084
2085         fflush_all();
2086         while (1) {
2087                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
2088                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
2089                  * insist on full MB_CUR_MAX buffer to declare input like
2090                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
2091                  *
2092                  * Note: read_key sets errno to 0 on success.
2093                  */
2094                 IF_FEATURE_EDITING_WINCH(S.ok_to_redraw = 1;)
2095                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
2096                 IF_FEATURE_EDITING_WINCH(S.ok_to_redraw = 0;)
2097                 if (errno) {
2098 #if ENABLE_UNICODE_SUPPORT
2099                         if (errno == EAGAIN && unicode_idx != 0)
2100                                 goto pushback;
2101 #endif
2102                         break;
2103                 }
2104
2105 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2106                 if ((int32_t)ic == KEYCODE_CURSOR_POS
2107                  && S.sent_ESC_br6n
2108                 ) {
2109                         S.sent_ESC_br6n = 0;
2110                         if (cursor == 0) { /* otherwise it may be bogus */
2111                                 int col = ((ic >> 32) & 0x7fff) - 1;
2112                                 /*
2113                                  * Is col > cmdedit_prmt_len?
2114                                  * If yes (terminal says cursor is farther to the right
2115                                  * of where we think it should be),
2116                                  * the prompt wasn't printed starting at col 1,
2117                                  * there was additional text before it.
2118                                  */
2119                                 if ((int)(col - cmdedit_prmt_len) > 0) {
2120                                         /* Fix our understanding of current x position */
2121                                         cmdedit_x += (col - cmdedit_prmt_len);
2122                                         while (cmdedit_x >= cmdedit_termw) {
2123                                                 cmdedit_x -= cmdedit_termw;
2124                                                 cmdedit_y++;
2125                                         }
2126                                 }
2127                         }
2128                         continue;
2129                 }
2130 #endif
2131
2132 #if ENABLE_UNICODE_SUPPORT
2133                 if (unicode_status == UNICODE_ON) {
2134                         wchar_t wc;
2135
2136                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
2137                                 break;
2138                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
2139
2140                         unicode_buf[unicode_idx++] = ic;
2141                         unicode_buf[unicode_idx] = '\0';
2142                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
2143                                 /* Not (yet?) a valid unicode char */
2144                                 if (unicode_idx < MB_CUR_MAX) {
2145                                         timeout = 50;
2146                                         continue;
2147                                 }
2148  pushback:
2149                                 /* Invalid sequence. Save all "bad bytes" except first */
2150                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
2151 # if !ENABLE_UNICODE_PRESERVE_BROKEN
2152                                 ic = CONFIG_SUBST_WCHAR;
2153 # else
2154                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
2155 # endif
2156                         } else {
2157                                 /* Valid unicode char, return its code */
2158                                 ic = wc;
2159                         }
2160                 }
2161 #endif
2162                 break;
2163         }
2164
2165         return ic;
2166 }
2167
2168 #if ENABLE_UNICODE_BIDI_SUPPORT
2169 static int isrtl_str(void)
2170 {
2171         int idx = cursor;
2172
2173         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
2174                 idx++;
2175         return unicode_bidi_isrtl(command_ps[idx]);
2176 }
2177 #else
2178 # define isrtl_str() 0
2179 #endif
2180
2181 /* leave out the "vi-mode"-only case labels if vi editing isn't
2182  * configured. */
2183 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
2184
2185 /* convert uppercase ascii to equivalent control char, for readability */
2186 #undef CTRL
2187 #define CTRL(a) ((a) & ~0x40)
2188
2189 enum {
2190         VI_CMDMODE_BIT = 0x40000000,
2191         /* 0x80000000 bit flags KEYCODE_xxx */
2192 };
2193
2194 #if ENABLE_FEATURE_REVERSE_SEARCH
2195 /* Mimic readline Ctrl-R reverse history search.
2196  * When invoked, it shows the following prompt:
2197  * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
2198  * and typing results in search being performed:
2199  * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
2200  * Search is performed by looking at progressively older lines in history.
2201  * Ctrl-R again searches for the next match in history.
2202  * Backspace deletes last matched char.
2203  * Control keys exit search and return to normal editing (at current history line).
2204  */
2205 static int32_t reverse_i_search(int timeout)
2206 {
2207         char match_buf[128]; /* for user input */
2208         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2209         const char *matched_history_line;
2210         const char *saved_prompt;
2211         unsigned saved_prmt_len;
2212         int32_t ic;
2213
2214         matched_history_line = NULL;
2215         read_key_buffer[0] = 0;
2216         match_buf[0] = '\0';
2217
2218         /* Save and replace the prompt */
2219         saved_prompt = prompt_last_line;
2220         saved_prmt_len = cmdedit_prmt_len;
2221         goto set_prompt;
2222
2223         while (1) {
2224                 int h;
2225                 unsigned match_buf_len = strlen(match_buf);
2226
2227 //FIXME: correct timeout? (i.e. count it down?)
2228                 ic = lineedit_read_key(read_key_buffer, timeout);
2229
2230                 switch (ic) {
2231                 case CTRL('R'): /* searching for the next match */
2232                         break;
2233
2234                 case '\b':
2235                 case '\x7f':
2236                         /* Backspace */
2237                         if (unicode_status == UNICODE_ON) {
2238                                 while (match_buf_len != 0) {
2239                                         uint8_t c = match_buf[--match_buf_len];
2240                                         if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
2241                                                 break; /* yes */
2242                                 }
2243                         } else {
2244                                 if (match_buf_len != 0)
2245                                         match_buf_len--;
2246                         }
2247                         match_buf[match_buf_len] = '\0';
2248                         break;
2249
2250                 default:
2251                         if (ic < ' '
2252                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2253                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2254                         ) {
2255                                 goto ret;
2256                         }
2257
2258                         /* Append this char */
2259 #if ENABLE_UNICODE_SUPPORT
2260                         if (unicode_status == UNICODE_ON) {
2261                                 mbstate_t mbstate = { 0 };
2262                                 char buf[MB_CUR_MAX + 1];
2263                                 int len = wcrtomb(buf, ic, &mbstate);
2264                                 if (len > 0) {
2265                                         buf[len] = '\0';
2266                                         if (match_buf_len + len < sizeof(match_buf))
2267                                                 strcpy(match_buf + match_buf_len, buf);
2268                                 }
2269                         } else
2270 #endif
2271                         if (match_buf_len < sizeof(match_buf) - 1) {
2272                                 match_buf[match_buf_len] = ic;
2273                                 match_buf[match_buf_len + 1] = '\0';
2274                         }
2275                         break;
2276                 } /* switch (ic) */
2277
2278                 /* Search in history for match_buf */
2279                 h = state->cur_history;
2280                 if (ic == CTRL('R'))
2281                         h--;
2282                 while (h >= 0) {
2283                         if (state->history[h]) {
2284                                 char *match = strstr(state->history[h], match_buf);
2285                                 if (match) {
2286                                         state->cur_history = h;
2287                                         matched_history_line = state->history[h];
2288                                         command_len = load_string(matched_history_line);
2289                                         cursor = match - matched_history_line;
2290 //FIXME: cursor position for Unicode case
2291
2292                                         free((char*)prompt_last_line);
2293  set_prompt:
2294                                         prompt_last_line = xasprintf("(reverse-i-search)'%s': ", match_buf);
2295                                         cmdedit_prmt_len = unicode_strwidth(prompt_last_line);
2296                                         goto do_redraw;
2297                                 }
2298                         }
2299                         h--;
2300                 }
2301
2302                 /* Not found */
2303                 match_buf[match_buf_len] = '\0';
2304                 beep();
2305                 continue;
2306
2307  do_redraw:
2308                 redraw(cmdedit_y, command_len - cursor);
2309         } /* while (1) */
2310
2311  ret:
2312         if (matched_history_line)
2313                 command_len = load_string(matched_history_line);
2314
2315         free((char*)prompt_last_line);
2316         prompt_last_line = saved_prompt;
2317         cmdedit_prmt_len = saved_prmt_len;
2318         redraw(cmdedit_y, command_len - cursor);
2319
2320         return ic;
2321 }
2322 #endif
2323
2324 /* maxsize must be >= 2.
2325  * Returns:
2326  * -1 on read errors or EOF, or on bare Ctrl-D,
2327  * 0  on ctrl-C (the line entered is still returned in 'command'),
2328  * (in both cases the cursor remains on the input line, '\n' is not printed)
2329  * >0 length of input string, including terminating '\n'
2330  */
2331 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize)
2332 {
2333         int len, n;
2334         int timeout;
2335 #if ENABLE_FEATURE_TAB_COMPLETION
2336         smallint lastWasTab = 0;
2337 #endif
2338         smallint break_out = 0;
2339 #if ENABLE_FEATURE_EDITING_VI
2340         smallint vi_cmdmode = 0;
2341 #endif
2342         struct termios initial_settings;
2343         struct termios new_settings;
2344         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2345
2346         INIT_S();
2347
2348         n = get_termios_and_make_raw(STDIN_FILENO, &new_settings, &initial_settings, 0
2349                 | TERMIOS_CLEAR_ISIG /* turn off INTR (ctrl-C), QUIT, SUSP */
2350         );
2351         if (n != 0 || (initial_settings.c_lflag & (ECHO|ICANON)) == ICANON) {
2352                 /* Happens when e.g. stty -echo was run before.
2353                  * But if ICANON is not set, we don't come here.
2354                  * (example: interactive python ^Z-backgrounded,
2355                  * tty is still in "raw mode").
2356                  */
2357                 parse_and_put_prompt(prompt);
2358                 fflush_all();
2359                 if (fgets(command, maxsize, stdin) == NULL)
2360                         len = -1; /* EOF or error */
2361                 else
2362                         len = strlen(command);
2363                 DEINIT_S();
2364                 return len;
2365         }
2366
2367         init_unicode();
2368
2369 // FIXME: audit & improve this
2370         if (maxsize > MAX_LINELEN)
2371                 maxsize = MAX_LINELEN;
2372         S.maxsize = maxsize;
2373
2374         timeout = -1;
2375         /* Make state->flags == 0 if st is NULL.
2376          * With zeroed flags, no other fields are ever referenced.
2377          */
2378         state = (line_input_t*) &const_int_0;
2379         if (st) {
2380                 state = st;
2381                 timeout = st->timeout;
2382         }
2383 #if MAX_HISTORY > 0
2384 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
2385         if (state->hist_file)
2386                 if (state->cnt_history == 0)
2387                         load_history(state);
2388 # endif
2389         if (state->flags & DO_HISTORY)
2390                 state->cur_history = state->cnt_history;
2391 #endif
2392
2393         /* prepare before init handlers */
2394         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
2395         command_len = 0;
2396 #if ENABLE_UNICODE_SUPPORT
2397         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
2398 #else
2399         command_ps = command;
2400         command[0] = '\0';
2401 #endif
2402 #define command command_must_not_be_used
2403
2404         tcsetattr_stdin_TCSANOW(&new_settings);
2405
2406 #if ENABLE_USERNAME_OR_HOMEDIR
2407         {
2408                 struct passwd *entry;
2409
2410                 entry = getpwuid(geteuid());
2411                 if (entry) {
2412                         user_buf = xstrdup(entry->pw_name);
2413                         home_pwd_buf = xstrdup(entry->pw_dir);
2414                 }
2415         }
2416 #endif
2417
2418 #if 0
2419         for (i = 0; i <= state->max_history; i++)
2420                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2421         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2422 #endif
2423
2424         /* Get width (before printing prompt) */
2425         cmdedit_termw = get_terminal_width(STDIN_FILENO);
2426         /* Print out the command prompt, optionally ask where cursor is */
2427         parse_and_put_prompt(prompt);
2428         ask_terminal();
2429
2430 #if ENABLE_FEATURE_EDITING_WINCH
2431         /* Install window resize handler (NB: after *all* init is complete) */
2432         S.SIGWINCH_handler.sa_handler = win_changed;
2433         S.SIGWINCH_handler.sa_flags = SA_RESTART;
2434         sigaction(SIGWINCH, &S.SIGWINCH_handler, &S.SIGWINCH_handler);
2435 #endif
2436         read_key_buffer[0] = 0;
2437         while (1) {
2438                 /*
2439                  * The emacs and vi modes share much of the code in the big
2440                  * command loop.  Commands entered when in vi's command mode
2441                  * (aka "escape mode") get an extra bit added to distinguish
2442                  * them - this keeps them from being self-inserted. This
2443                  * clutters the big switch a bit, but keeps all the code
2444                  * in one place.
2445                  */
2446                 int32_t ic, ic_raw;
2447 #if ENABLE_FEATURE_EDITING_WINCH
2448                 unsigned count;
2449
2450                 count = S.SIGWINCH_count;
2451                 if (S.SIGWINCH_saved != count) {
2452                         S.SIGWINCH_saved = count;
2453                         cmdedit_setwidth();
2454                 }
2455 #endif
2456                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2457
2458 #if ENABLE_FEATURE_REVERSE_SEARCH
2459  again:
2460 #endif
2461 #if ENABLE_FEATURE_EDITING_VI
2462                 newdelflag = 1;
2463                 if (vi_cmdmode) {
2464                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2465                          * change ic if it contains one of them: */
2466                         ic |= VI_CMDMODE_BIT;
2467                 }
2468 #endif
2469
2470                 switch (ic) {
2471                 case '\n':
2472                 case '\r':
2473                 vi_case('\n'|VI_CMDMODE_BIT:)
2474                 vi_case('\r'|VI_CMDMODE_BIT:)
2475                         /* Enter */
2476                         goto_new_line();
2477                         break_out = 1;
2478                         break;
2479                 case CTRL('A'):
2480                 vi_case('0'|VI_CMDMODE_BIT:)
2481                         /* Control-a -- Beginning of line */
2482                         input_backward(cursor);
2483                         break;
2484                 case CTRL('B'):
2485                 vi_case('h'|VI_CMDMODE_BIT:)
2486                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2487                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2488                         input_backward(1); /* Move back one character */
2489                         break;
2490                 case CTRL('E'):
2491                 vi_case('$'|VI_CMDMODE_BIT:)
2492                         /* Control-e -- End of line */
2493                         put_till_end_and_adv_cursor();
2494                         break;
2495                 case CTRL('F'):
2496                 vi_case('l'|VI_CMDMODE_BIT:)
2497                 vi_case(' '|VI_CMDMODE_BIT:)
2498                         input_forward(); /* Move forward one character */
2499                         break;
2500                 case '\b':   /* ^H */
2501                 case '\x7f': /* DEL */
2502                         if (!isrtl_str())
2503                                 input_backspace();
2504                         else
2505                                 input_delete(0);
2506                         break;
2507                 case KEYCODE_DELETE:
2508                         if (!isrtl_str())
2509                                 input_delete(0);
2510                         else
2511                                 input_backspace();
2512                         break;
2513 #if ENABLE_FEATURE_TAB_COMPLETION
2514                 case '\t':
2515                         input_tab(&lastWasTab);
2516                         break;
2517 #endif
2518                 case CTRL('K'):
2519                         /* Control-k -- clear to end of line */
2520                         command_ps[cursor] = BB_NUL;
2521                         command_len = cursor;
2522                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2523                         break;
2524                 case CTRL('L'):
2525                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2526                         /* Control-l -- clear screen */
2527                         /* cursor to top,left; clear to the end of screen */
2528                         printf(ESC"[H" ESC"[J");
2529                         draw_full(command_len - cursor);
2530                         break;
2531 #if MAX_HISTORY > 0
2532                 case CTRL('N'):
2533                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2534                 vi_case('j'|VI_CMDMODE_BIT:)
2535                         /* Control-n -- Get next command in history */
2536                         if (get_next_history())
2537                                 goto rewrite_line;
2538                         break;
2539                 case CTRL('P'):
2540                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2541                 vi_case('k'|VI_CMDMODE_BIT:)
2542                         /* Control-p -- Get previous command from history */
2543                         if (get_previous_history())
2544                                 goto rewrite_line;
2545                         break;
2546 #endif
2547                 case CTRL('U'):
2548                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2549                         /* Control-U -- Clear line before cursor */
2550                         if (cursor) {
2551                                 command_len -= cursor;
2552                                 memmove(command_ps, command_ps + cursor,
2553                                         (command_len + 1) * sizeof(command_ps[0]));
2554                                 redraw(cmdedit_y, command_len);
2555                         }
2556                         break;
2557                 case CTRL('W'):
2558                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2559                         /* Control-W -- Remove the last word */
2560                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2561                                 input_backspace();
2562                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2563                                 input_backspace();
2564                         break;
2565                 case KEYCODE_ALT_D: {
2566                         /* Delete word forward */
2567                         int nc, sc = cursor;
2568                         ctrl_right();
2569                         nc = cursor - sc;
2570                         input_backward(nc);
2571                         while (--nc >= 0)
2572                                 input_delete(1);
2573                         break;
2574                 }
2575                 case KEYCODE_ALT_BACKSPACE: {
2576                         /* Delete word backward */
2577                         int sc = cursor;
2578                         ctrl_left();
2579                         while (sc-- > cursor)
2580                                 input_delete(1);
2581                         break;
2582                 }
2583 #if ENABLE_FEATURE_REVERSE_SEARCH
2584                 case CTRL('R'):
2585                         ic = ic_raw = reverse_i_search(timeout);
2586                         goto again;
2587 #endif
2588
2589 #if ENABLE_FEATURE_EDITING_VI
2590                 case 'i'|VI_CMDMODE_BIT:
2591                         vi_cmdmode = 0;
2592                         break;
2593                 case 'I'|VI_CMDMODE_BIT:
2594                         input_backward(cursor);
2595                         vi_cmdmode = 0;
2596                         break;
2597                 case 'a'|VI_CMDMODE_BIT:
2598                         input_forward();
2599                         vi_cmdmode = 0;
2600                         break;
2601                 case 'A'|VI_CMDMODE_BIT:
2602                         put_till_end_and_adv_cursor();
2603                         vi_cmdmode = 0;
2604                         break;
2605                 case 'x'|VI_CMDMODE_BIT:
2606                         input_delete(1);
2607                         break;
2608                 case 'X'|VI_CMDMODE_BIT:
2609                         if (cursor > 0) {
2610                                 input_backward(1);
2611                                 input_delete(1);
2612                         }
2613                         break;
2614                 case 'W'|VI_CMDMODE_BIT:
2615                         vi_Word_motion(1);
2616                         break;
2617                 case 'w'|VI_CMDMODE_BIT:
2618                         vi_word_motion(1);
2619                         break;
2620                 case 'E'|VI_CMDMODE_BIT:
2621                         vi_End_motion();
2622                         break;
2623                 case 'e'|VI_CMDMODE_BIT:
2624                         vi_end_motion();
2625                         break;
2626                 case 'B'|VI_CMDMODE_BIT:
2627                         vi_Back_motion();
2628                         break;
2629                 case 'b'|VI_CMDMODE_BIT:
2630                         vi_back_motion();
2631                         break;
2632                 case 'C'|VI_CMDMODE_BIT:
2633                         vi_cmdmode = 0;
2634                         /* fall through */
2635                 case 'D'|VI_CMDMODE_BIT:
2636                         goto clear_to_eol;
2637
2638                 case 'c'|VI_CMDMODE_BIT:
2639                         vi_cmdmode = 0;
2640                         /* fall through */
2641                 case 'd'|VI_CMDMODE_BIT: {
2642                         int nc, sc;
2643
2644                         ic = lineedit_read_key(read_key_buffer, timeout);
2645                         if (errno) /* error */
2646                                 goto return_error_indicator;
2647                         if (ic == ic_raw) { /* "cc", "dd" */
2648                                 input_backward(cursor);
2649                                 goto clear_to_eol;
2650                                 break;
2651                         }
2652
2653                         sc = cursor;
2654                         switch (ic) {
2655                         case 'w':
2656                         case 'W':
2657                         case 'e':
2658                         case 'E':
2659                                 switch (ic) {
2660                                 case 'w':   /* "dw", "cw" */
2661                                         vi_word_motion(vi_cmdmode);
2662                                         break;
2663                                 case 'W':   /* 'dW', 'cW' */
2664                                         vi_Word_motion(vi_cmdmode);
2665                                         break;
2666                                 case 'e':   /* 'de', 'ce' */
2667                                         vi_end_motion();
2668                                         input_forward();
2669                                         break;
2670                                 case 'E':   /* 'dE', 'cE' */
2671                                         vi_End_motion();
2672                                         input_forward();
2673                                         break;
2674                                 }
2675                                 nc = cursor;
2676                                 input_backward(cursor - sc);
2677                                 while (nc-- > cursor)
2678                                         input_delete(1);
2679                                 break;
2680                         case 'b':  /* "db", "cb" */
2681                         case 'B':  /* implemented as B */
2682                                 if (ic == 'b')
2683                                         vi_back_motion();
2684                                 else
2685                                         vi_Back_motion();
2686                                 while (sc-- > cursor)
2687                                         input_delete(1);
2688                                 break;
2689                         case ' ':  /* "d ", "c " */
2690                                 input_delete(1);
2691                                 break;
2692                         case '$':  /* "d$", "c$" */
2693  clear_to_eol:
2694                                 while (cursor < command_len)
2695                                         input_delete(1);
2696                                 break;
2697                         }
2698                         break;
2699                 }
2700                 case 'p'|VI_CMDMODE_BIT:
2701                         input_forward();
2702                         /* fallthrough */
2703                 case 'P'|VI_CMDMODE_BIT:
2704                         put();
2705                         break;
2706                 case 'r'|VI_CMDMODE_BIT:
2707 //FIXME: unicode case?
2708                         ic = lineedit_read_key(read_key_buffer, timeout);
2709                         if (errno) /* error */
2710                                 goto return_error_indicator;
2711                         if (ic < ' ' || ic > 255) {
2712                                 beep();
2713                         } else {
2714                                 command_ps[cursor] = ic;
2715                                 bb_putchar(ic);
2716                                 bb_putchar('\b');
2717                         }
2718                         break;
2719                 case '\x1b': /* ESC */
2720                         if (state->flags & VI_MODE) {
2721                                 /* insert mode --> command mode */
2722                                 vi_cmdmode = 1;
2723                                 input_backward(1);
2724                         }
2725                         break;
2726 #endif /* FEATURE_COMMAND_EDITING_VI */
2727
2728 #if MAX_HISTORY > 0
2729                 case KEYCODE_UP:
2730                         if (get_previous_history())
2731                                 goto rewrite_line;
2732                         beep();
2733                         break;
2734                 case KEYCODE_DOWN:
2735                         if (!get_next_history())
2736                                 break;
2737  rewrite_line:
2738                         /* Rewrite the line with the selected history item */
2739                         /* change command */
2740                         command_len = load_string(state->history[state->cur_history] ?
2741                                         state->history[state->cur_history] : "");
2742                         /* redraw and go to eol (bol, in vi) */
2743                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2744                         break;
2745 #endif
2746                 case KEYCODE_RIGHT:
2747                         input_forward();
2748                         break;
2749                 case KEYCODE_LEFT:
2750                         input_backward(1);
2751                         break;
2752                 case KEYCODE_CTRL_LEFT:
2753                 case KEYCODE_ALT_LEFT: /* bash doesn't do it */
2754                         ctrl_left();
2755                         break;
2756                 case KEYCODE_CTRL_RIGHT:
2757                 case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
2758                         ctrl_right();
2759                         break;
2760                 case KEYCODE_HOME:
2761                         input_backward(cursor);
2762                         break;
2763                 case KEYCODE_END:
2764                         put_till_end_and_adv_cursor();
2765                         break;
2766
2767                 default:
2768                         if (initial_settings.c_cc[VINTR] != 0
2769                          && ic_raw == initial_settings.c_cc[VINTR]
2770                         ) {
2771                                 /* Ctrl-C (usually) - stop gathering input */
2772                                 command_len = 0;
2773                                 break_out = -1; /* "do not append '\n'" */
2774                                 break;
2775                         }
2776                         if (initial_settings.c_cc[VEOF] != 0
2777                          && ic_raw == initial_settings.c_cc[VEOF]
2778                         ) {
2779                                 /* Ctrl-D (usually) - delete one character,
2780                                  * or exit if len=0 and no chars to delete */
2781                                 if (command_len == 0) {
2782                                         errno = 0;
2783
2784                 case -1: /* error (e.g. EIO when tty is destroyed) */
2785  IF_FEATURE_EDITING_VI(return_error_indicator:)
2786                                         break_out = command_len = -1;
2787                                         break;
2788                                 }
2789                                 input_delete(0);
2790                                 break;
2791                         }
2792 //                      /* Control-V -- force insert of next char */
2793 //                      if (c == CTRL('V')) {
2794 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2795 //                                      goto return_error_indicator;
2796 //                              if (c == 0) {
2797 //                                      beep();
2798 //                                      break;
2799 //                              }
2800 //                      }
2801                         if (ic < ' '
2802                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2803                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2804                         ) {
2805                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2806                                  * and vi mode ignores unexpected chars.
2807                                  * Otherwise, we are here if ic is a
2808                                  * control char or an unhandled ESC sequence,
2809                                  * which is also ignored.
2810                                  */
2811                                 break;
2812                         }
2813                         if ((int)command_len >= (maxsize - 2)) {
2814                                 /* Not enough space for the char and EOL */
2815                                 break;
2816                         }
2817
2818                         command_len++;
2819                         if (cursor == (command_len - 1)) {
2820                                 /* We are at the end, append */
2821                                 command_ps[cursor] = ic;
2822                                 command_ps[cursor + 1] = BB_NUL;
2823                                 put_cur_glyph_and_inc_cursor();
2824                                 if (unicode_bidi_isrtl(ic))
2825                                         input_backward(1);
2826                         } else {
2827                                 /* In the middle, insert */
2828                                 int sc = cursor;
2829
2830                                 memmove(command_ps + sc + 1, command_ps + sc,
2831                                         (command_len - sc) * sizeof(command_ps[0]));
2832                                 command_ps[sc] = ic;
2833                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2834                                 if (!isrtl_str())
2835                                         sc++; /* no */
2836                                 put_till_end_and_adv_cursor();
2837                                 /* to prev x pos + 1 */
2838                                 input_backward(cursor - sc);
2839                         }
2840                         break;
2841                 } /* switch (ic) */
2842
2843                 if (break_out)
2844                         break;
2845
2846 #if ENABLE_FEATURE_TAB_COMPLETION
2847                 if (ic_raw != '\t')
2848                         lastWasTab = 0;
2849 #endif
2850         } /* while (1) */
2851
2852 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2853         if (S.sent_ESC_br6n) {
2854                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2855                  * We sent "ESC [ 6 n", but got '\n' first, and
2856                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2857                  * It's bad already and not much can be done with it
2858                  * (it _will_ be visible for the next process to read stdin),
2859                  * but without this delay it even shows up on the screen
2860                  * as garbage because we restore echo settings with tcsetattr
2861                  * before it comes in. UGLY!
2862                  */
2863                 usleep(20*1000);
2864         }
2865 #endif
2866
2867 /* End of bug-catching "command_must_not_be_used" trick */
2868 #undef command
2869
2870 #if ENABLE_UNICODE_SUPPORT
2871         command[0] = '\0';
2872         if (command_len > 0)
2873                 command_len = save_string(command, maxsize - 1);
2874         free(command_ps);
2875 #endif
2876
2877         if (command_len > 0) {
2878                 remember_in_history(command);
2879         }
2880
2881         if (break_out > 0) {
2882                 command[command_len++] = '\n';
2883                 command[command_len] = '\0';
2884         }
2885
2886 #if ENABLE_FEATURE_TAB_COMPLETION
2887         free_tab_completion_data();
2888 #endif
2889
2890         /* restore initial_settings */
2891         tcsetattr_stdin_TCSANOW(&initial_settings);
2892 #if ENABLE_FEATURE_EDITING_WINCH
2893         /* restore SIGWINCH handler */
2894         sigaction_set(SIGWINCH, &S.SIGWINCH_handler);
2895 #endif
2896         fflush_all();
2897
2898         len = command_len;
2899         DEINIT_S();
2900
2901         return len; /* can't return command_len, DEINIT_S() destroys it */
2902 }
2903
2904 #else  /* !FEATURE_EDITING */
2905
2906 #undef read_line_input
2907 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2908 {
2909         fputs(prompt, stdout);
2910         fflush_all();
2911         if (!fgets(command, maxsize, stdin))
2912                 return -1;
2913         return strlen(command);
2914 }
2915
2916 #endif  /* !FEATURE_EDITING */
2917
2918
2919 /*
2920  * Testing
2921  */
2922
2923 #ifdef TEST
2924
2925 #include <locale.h>
2926
2927 const char *applet_name = "debug stuff usage";
2928
2929 int main(int argc, char **argv)
2930 {
2931         char buff[MAX_LINELEN];
2932         char *prompt =
2933 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2934                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2935                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2936                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[m\\]";
2937 #else
2938                 "% ";
2939 #endif
2940
2941         while (1) {
2942                 int l;
2943                 l = read_line_input(prompt, buff);
2944                 if (l <= 0 || buff[l-1] != '\n')
2945                         break;
2946                 buff[l-1] = '\0';
2947                 printf("*** read_line_input() returned line =%s=\n", buff);
2948         }
2949         printf("*** read_line_input() detect ^D\n");
2950         return 0;
2951 }
2952
2953 #endif  /* TEST */