libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16
  17 /*
  18  * Usage and known bugs:
  19  * Terminal key codes are not extensive, more needs to be added.
  20  * This version was created on Debian GNU/Linux 2.x.
  21  * Delete, Backspace, Home, End, and the arrow keys were tested
  22  * to work in an Xterm and console. Ctrl-A also works as Home.
  23  * Ctrl-E also works as End.
  24  *
  25  * The following readline-like commands are not implemented:
  26  * ESC-b -- Move back one word
  27  * ESC-f -- Move forward one word
  28  * ESC-d -- Delete forward one word
  29  * CTL-t -- Transpose two characters
  30  *
  31  * lineedit does not know that the terminal escape sequences do not
  32  * take up space on the screen. The redisplay code assumes, unless
  33  * told otherwise, that each character in the prompt is a printable
  34  * character that takes up one character position on the screen.
  35  * You need to tell lineedit that some sequences of characters
  36  * in the prompt take up no screen space. Compatibly with readline,
  37  * use the \[ escape to begin a sequence of non-printing characters,
  38  * and the \] escape to signal the end of such a sequence. Example:
  39  *
  40  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  41  */
  42 #include "libbb.h"
  43 #include "unicode.h"
  44
  45 #ifdef TEST
  46 # define ENABLE_FEATURE_EDITING 0
  47 # define ENABLE_FEATURE_TAB_COMPLETION 0
  48 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  49 #endif
  50
  51
  52 /* Entire file (except TESTing part) sits inside this #if */
  53 #if ENABLE_FEATURE_EDITING
  54
  55
  56 #define ENABLE_USERNAME_OR_HOMEDIR \
  57         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  58 #define IF_USERNAME_OR_HOMEDIR(...)
  59 #if ENABLE_USERNAME_OR_HOMEDIR
  60 # undef IF_USERNAME_OR_HOMEDIR
  61 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  62 #endif
  63
  64
  65 #undef CHAR_T
  66 #if ENABLE_UNICODE_SUPPORT
  67 # define BB_NUL ((wchar_t)0)
  68 # define CHAR_T wchar_t
  69 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  70 # if ENABLE_FEATURE_EDITING_VI
  71 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  72 # endif
  73 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  74 # undef isspace
  75 # undef isalnum
  76 # undef ispunct
  77 # undef isprint
  78 # define isspace isspace_must_not_be_used
  79 # define isalnum isalnum_must_not_be_used
  80 # define ispunct ispunct_must_not_be_used
  81 # define isprint isprint_must_not_be_used
  82 #else
  83 # define BB_NUL '\0'
  84 # define CHAR_T char
  85 # define BB_isspace(c) isspace(c)
  86 # define BB_isalnum(c) isalnum(c)
  87 # define BB_ispunct(c) ispunct(c)
  88 #endif
  89 #if ENABLE_UNICODE_PRESERVE_BROKEN
  90 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
  91 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
  92 #else
  93 # define unicode_is_raw_byte(wc)     0
  94 #endif
  95
  96
  97 #define SEQ_CLEAR_TILL_END_OF_SCREEN "\033[J"
  98 //#define SEQ_CLEAR_TILL_END_OF_LINE   "\033[K"
  99
 100
 101 enum {
 102         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 103                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 104                       : 0x7ff0
 105 };
 106
 107 #if ENABLE_USERNAME_OR_HOMEDIR
 108 static const char null_str[] ALIGN1 = "";
 109 #endif
 110
 111 /* We try to minimize both static and stack usage. */
 112 struct lineedit_statics {
 113         line_input_t *state;
 114
 115         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 116         sighandler_t previous_SIGWINCH_handler;
 117
 118         unsigned cmdedit_x;        /* real x (col) terminal position */
 119         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 120         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 121
 122         unsigned cursor;
 123         int command_len; /* must be signed */
 124         /* signed maxsize: we want x in "if (x > S.maxsize)"
 125          * to _not_ be promoted to unsigned */
 126         int maxsize;
 127         CHAR_T *command_ps;
 128
 129         const char *cmdedit_prompt;
 130 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 131         int num_ok_lines; /* = 1; */
 132 #endif
 133
 134 #if ENABLE_USERNAME_OR_HOMEDIR
 135         char *user_buf;
 136         char *home_pwd_buf; /* = (char*)null_str; */
 137 #endif
 138
 139 #if ENABLE_FEATURE_TAB_COMPLETION
 140         char **matches;
 141         unsigned num_matches;
 142 #endif
 143
 144 #if ENABLE_FEATURE_EDITING_VI
 145 # define DELBUFSIZ 128
 146         CHAR_T *delptr;
 147         smallint newdelflag;     /* whether delbuf should be reused yet */
 148         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 149 #endif
 150 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 151         smallint sent_ESC_br6n;
 152 #endif
 153 };
 154
 155 /* See lineedit_ptr_hack.c */
 156 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 157
 158 #define S (*lineedit_ptr_to_statics)
 159 #define state            (S.state           )
 160 #define cmdedit_termw    (S.cmdedit_termw   )
 161 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 162 #define cmdedit_x        (S.cmdedit_x       )
 163 #define cmdedit_y        (S.cmdedit_y       )
 164 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 165 #define cursor           (S.cursor          )
 166 #define command_len      (S.command_len     )
 167 #define command_ps       (S.command_ps      )
 168 #define cmdedit_prompt   (S.cmdedit_prompt  )
 169 #define num_ok_lines     (S.num_ok_lines    )
 170 #define user_buf         (S.user_buf        )
 171 #define home_pwd_buf     (S.home_pwd_buf    )
 172 #define matches          (S.matches         )
 173 #define num_matches      (S.num_matches     )
 174 #define delptr           (S.delptr          )
 175 #define newdelflag       (S.newdelflag      )
 176 #define delbuf           (S.delbuf          )
 177
 178 #define INIT_S() do { \
 179         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 180         barrier(); \
 181         cmdedit_termw = 80; \
 182         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
 183         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 184 } while (0)
 185 static void deinit_S(void)
 186 {
 187 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 188         /* This one is allocated only if FANCY_PROMPT is on
 189          * (otherwise it points to verbatim prompt (NOT malloced)) */
 190         free((char*)cmdedit_prompt);
 191 #endif
 192 #if ENABLE_USERNAME_OR_HOMEDIR
 193         free(user_buf);
 194         if (home_pwd_buf != null_str)
 195                 free(home_pwd_buf);
 196 #endif
 197         free(lineedit_ptr_to_statics);
 198 }
 199 #define DEINIT_S() deinit_S()
 200
 201
 202 #if ENABLE_UNICODE_SUPPORT
 203 static size_t load_string(const char *src, int maxsize)
 204 {
 205         ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
 206         if (len < 0)
 207                 len = 0;
 208         command_ps[len] = BB_NUL;
 209         return len;
 210 }
 211 static unsigned save_string(char *dst, unsigned maxsize)
 212 {
 213 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 214         ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 215         if (len < 0)
 216                 len = 0;
 217         dst[len] = '\0';
 218         return len;
 219 # else
 220         unsigned dstpos = 0;
 221         unsigned srcpos = 0;
 222
 223         maxsize--;
 224         while (dstpos < maxsize) {
 225                 wchar_t wc;
 226                 int n = srcpos;
 227
 228                 /* Convert up to 1st invalid byte (or up to end) */
 229                 while ((wc = command_ps[srcpos]) != BB_NUL
 230                     && !unicode_is_raw_byte(wc)
 231                 ) {
 232                         srcpos++;
 233                 }
 234                 command_ps[srcpos] = BB_NUL;
 235                 n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 236                 if (n < 0) /* should not happen */
 237                         break;
 238                 dstpos += n;
 239                 if (wc == BB_NUL) /* usually is */
 240                         break;
 241
 242                 /* We do have invalid byte here! */
 243                 command_ps[srcpos] = wc; /* restore it */
 244                 srcpos++;
 245                 if (dstpos == maxsize)
 246                         break;
 247                 dst[dstpos++] = (char) wc;
 248         }
 249         dst[dstpos] = '\0';
 250         return dstpos;
 251 # endif
 252 }
 253 /* I thought just fputwc(c, stdout) would work. But no... */
 254 static void BB_PUTCHAR(wchar_t c)
 255 {
 256         char buf[MB_CUR_MAX + 1];
 257         mbstate_t mbst = { 0 };
 258         ssize_t len;
 259
 260         len = wcrtomb(buf, c, &mbst);
 261         if (len > 0) {
 262                 buf[len] = '\0';
 263                 fputs(buf, stdout);
 264         }
 265 }
 266 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 267 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 268 # else
 269 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 270 #  define adjust_width_and_validate_wc(width_adj, wc) \
 271         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 272 # endif
 273 {
 274         int w = 1;
 275
 276         if (unicode_status == UNICODE_ON) {
 277                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 278                         /* note: also true for unicode_is_raw_byte(wc) */
 279                         goto subst;
 280                 }
 281                 w = wcwidth(wc);
 282                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 283                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 284                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 285                 ) {
 286  subst:
 287                         w = 1;
 288                         wc = CONFIG_SUBST_WCHAR;
 289                 }
 290         }
 291
 292 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 293         *width_adj += w;
 294 #endif
 295         return wc;
 296 }
 297 #else /* !UNICODE */
 298 static size_t load_string(const char *src, int maxsize)
 299 {
 300         safe_strncpy(command_ps, src, maxsize);
 301         return strlen(command_ps);
 302 }
 303 # if ENABLE_FEATURE_TAB_COMPLETION
 304 static void save_string(char *dst, unsigned maxsize)
 305 {
 306         safe_strncpy(dst, command_ps, maxsize);
 307 }
 308 # endif
 309 # define BB_PUTCHAR(c) bb_putchar(c)
 310 /* Should never be called: */
 311 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 312 #endif
 313
 314
 315 /* Put 'command_ps[cursor]', cursor++.
 316  * Advance cursor on screen. If we reached right margin, scroll text up
 317  * and remove terminal margin effect by printing 'next_char' */
 318 #define HACK_FOR_WRONG_WIDTH 1
 319 static void put_cur_glyph_and_inc_cursor(void)
 320 {
 321         CHAR_T c = command_ps[cursor];
 322         unsigned width = 0;
 323         int ofs_to_right;
 324
 325         if (c == BB_NUL) {
 326                 /* erase character after end of input string */
 327                 c = ' ';
 328         } else {
 329                 /* advance cursor only if we aren't at the end yet */
 330                 cursor++;
 331                 if (unicode_status == UNICODE_ON) {
 332                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 333                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 334                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 335                 } else {
 336                         cmdedit_x++;
 337                 }
 338         }
 339
 340         ofs_to_right = cmdedit_x - cmdedit_termw;
 341         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 342                 /* c fits on this line */
 343                 BB_PUTCHAR(c);
 344         }
 345
 346         if (ofs_to_right >= 0) {
 347                 /* we go to the next line */
 348 #if HACK_FOR_WRONG_WIDTH
 349                 /* This works better if our idea of term width is wrong
 350                  * and it is actually wider (often happens on serial lines).
 351                  * Printing CR,LF *forces* cursor to next line.
 352                  * OTOH if terminal width is correct AND terminal does NOT
 353                  * have automargin (IOW: it is moving cursor to next line
 354                  * by itself (which is wrong for VT-10x terminals)),
 355                  * this will break things: there will be one extra empty line */
 356                 puts("\r"); /* + implicit '\n' */
 357 #else
 358                 /* VT-10x terminals don't wrap cursor to next line when last char
 359                  * on the line is printed - cursor stays "over" this char.
 360                  * Need to print _next_ char too (first one to appear on next line)
 361                  * to make cursor move down to next line.
 362                  */
 363                 /* Works ok only if cmdedit_termw is correct. */
 364                 c = command_ps[cursor];
 365                 if (c == BB_NUL)
 366                         c = ' ';
 367                 BB_PUTCHAR(c);
 368                 bb_putchar('\b');
 369 #endif
 370                 cmdedit_y++;
 371                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 372                         width = 0;
 373                 } else { /* ofs_to_right > 0 */
 374                         /* wide char c didn't fit on prev line */
 375                         BB_PUTCHAR(c);
 376                 }
 377                 cmdedit_x = width;
 378         }
 379 }
 380
 381 /* Move to end of line (by printing all chars till the end) */
 382 static void put_till_end_and_adv_cursor(void)
 383 {
 384         while (cursor < command_len)
 385                 put_cur_glyph_and_inc_cursor();
 386 }
 387
 388 /* Go to the next line */
 389 static void goto_new_line(void)
 390 {
 391         put_till_end_and_adv_cursor();
 392         if (cmdedit_x != 0)
 393                 bb_putchar('\n');
 394 }
 395
 396 static void beep(void)
 397 {
 398         bb_putchar('\007');
 399 }
 400
 401 static void put_prompt(void)
 402 {
 403         unsigned w;
 404
 405         fputs(cmdedit_prompt, stdout);
 406         fflush_all();
 407         cursor = 0;
 408         w = cmdedit_termw; /* read volatile var once */
 409         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 410         cmdedit_x = cmdedit_prmt_len % w;
 411 }
 412
 413 /* Move back one character */
 414 /* (optimized for slow terminals) */
 415 static void input_backward(unsigned num)
 416 {
 417         if (num > cursor)
 418                 num = cursor;
 419         if (num == 0)
 420                 return;
 421         cursor -= num;
 422
 423         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 424          && unicode_status == UNICODE_ON
 425         ) {
 426                 /* correct NUM to be equal to _screen_ width */
 427                 int n = num;
 428                 num = 0;
 429                 while (--n >= 0)
 430                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 431                 if (num == 0)
 432                         return;
 433         }
 434
 435         if (cmdedit_x >= num) {
 436                 cmdedit_x -= num;
 437                 if (num <= 4) {
 438                         /* This is longer by 5 bytes on x86.
 439                          * Also gets miscompiled for ARM users
 440                          * (busybox.net/bugs/view.php?id=2274).
 441                          * printf(("\b\b\b\b" + 4) - num);
 442                          * return;
 443                          */
 444                         do {
 445                                 bb_putchar('\b');
 446                         } while (--num);
 447                         return;
 448                 }
 449                 printf("\033[%uD", num);
 450                 return;
 451         }
 452
 453         /* Need to go one or more lines up */
 454         if (ENABLE_UNICODE_WIDE_WCHARS) {
 455                 /* With wide chars, it is hard to "backtrack"
 456                  * and reliably figure out where to put cursor.
 457                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 458                  * |prompt: <><> |
 459                  * |<><><><><><> |
 460                  * |_            |
 461                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 462                  * We need to go up one line, and then - how do we know that
 463                  * we need to go *10* positions to the right? Because
 464                  * |prompt: <>#<>|
 465                  * |<><><>#<><><>|
 466                  * |_            |
 467                  * in this situation we need to go *11* positions to the right.
 468                  *
 469                  * A simpler thing to do is to redraw everything from the start
 470                  * up to new cursor position (which is already known):
 471                  */
 472                 unsigned sv_cursor;
 473                 /* go to 1st column; go up to first line */
 474                 printf("\r" "\033[%uA", cmdedit_y);
 475                 cmdedit_y = 0;
 476                 sv_cursor = cursor;
 477                 put_prompt(); /* sets cursor to 0 */
 478                 while (cursor < sv_cursor)
 479                         put_cur_glyph_and_inc_cursor();
 480         } else {
 481                 int lines_up;
 482                 unsigned width;
 483                 /* num = chars to go back from the beginning of current line: */
 484                 num -= cmdedit_x;
 485                 width = cmdedit_termw; /* read volatile var once */
 486                 /* num=1...w: one line up, w+1...2w: two, etc: */
 487                 lines_up = 1 + (num - 1) / width;
 488                 cmdedit_x = (width * cmdedit_y - num) % width;
 489                 cmdedit_y -= lines_up;
 490                 /* go to 1st column; go up */
 491                 printf("\r" "\033[%uA", lines_up);
 492                 /* go to correct column.
 493                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 494                  * need to *make sure* we skip it if cmdedit_x == 0 */
 495                 if (cmdedit_x)
 496                         printf("\033[%uC", cmdedit_x);
 497         }
 498 }
 499
 500 /* draw prompt, editor line, and clear tail */
 501 static void redraw(int y, int back_cursor)
 502 {
 503         if (y > 0) /* up y lines */
 504                 printf("\033[%uA", y);
 505         bb_putchar('\r');
 506         put_prompt();
 507         put_till_end_and_adv_cursor();
 508         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 509         input_backward(back_cursor);
 510 }
 511
 512 /* Delete the char in front of the cursor, optionally saving it
 513  * for later putback */
 514 #if !ENABLE_FEATURE_EDITING_VI
 515 static void input_delete(void)
 516 #define input_delete(save) input_delete()
 517 #else
 518 static void input_delete(int save)
 519 #endif
 520 {
 521         int j = cursor;
 522
 523         if (j == (int)command_len)
 524                 return;
 525
 526 #if ENABLE_FEATURE_EDITING_VI
 527         if (save) {
 528                 if (newdelflag) {
 529                         delptr = delbuf;
 530                         newdelflag = 0;
 531                 }
 532                 if ((delptr - delbuf) < DELBUFSIZ)
 533                         *delptr++ = command_ps[j];
 534         }
 535 #endif
 536
 537         memmove(command_ps + j, command_ps + j + 1,
 538                         /* (command_len + 1 [because of NUL]) - (j + 1)
 539                          * simplified into (command_len - j) */
 540                         (command_len - j) * sizeof(command_ps[0]));
 541         command_len--;
 542         put_till_end_and_adv_cursor();
 543         /* Last char is still visible, erase it (and more) */
 544         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 545         input_backward(cursor - j);     /* back to old pos cursor */
 546 }
 547
 548 #if ENABLE_FEATURE_EDITING_VI
 549 static void put(void)
 550 {
 551         int ocursor;
 552         int j = delptr - delbuf;
 553
 554         if (j == 0)
 555                 return;
 556         ocursor = cursor;
 557         /* open hole and then fill it */
 558         memmove(command_ps + cursor + j, command_ps + cursor,
 559                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 560         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 561         command_len += j;
 562         put_till_end_and_adv_cursor();
 563         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 564 }
 565 #endif
 566
 567 /* Delete the char in back of the cursor */
 568 static void input_backspace(void)
 569 {
 570         if (cursor > 0) {
 571                 input_backward(1);
 572                 input_delete(0);
 573         }
 574 }
 575
 576 /* Move forward one character */
 577 static void input_forward(void)
 578 {
 579         if (cursor < command_len)
 580                 put_cur_glyph_and_inc_cursor();
 581 }
 582
 583 #if ENABLE_FEATURE_TAB_COMPLETION
 584
 585 static void free_tab_completion_data(void)
 586 {
 587         if (matches) {
 588                 while (num_matches)
 589                         free(matches[--num_matches]);
 590                 free(matches);
 591                 matches = NULL;
 592         }
 593 }
 594
 595 static void add_match(char *matched)
 596 {
 597         matches = xrealloc_vector(matches, 4, num_matches);
 598         matches[num_matches] = matched;
 599         num_matches++;
 600 }
 601
 602 #if ENABLE_FEATURE_USERNAME_COMPLETION
 603 /* Replace "~user/..." with "/homedir/...".
 604  * The parameter is malloced, free it or return it
 605  * unchanged if no user is matched.
 606  */
 607 static char *username_path_completion(char *ud)
 608 {
 609         struct passwd *entry;
 610         char *tilde_name = ud;
 611         char *home = NULL;
 612
 613         ud++; /* skip ~ */
 614         if (*ud == '/') {       /* "~/..." */
 615                 home = home_pwd_buf;
 616         } else {
 617                 /* "~user/..." */
 618                 ud = strchr(ud, '/');
 619                 *ud = '\0';           /* "~user" */
 620                 entry = getpwnam(tilde_name + 1);
 621                 *ud = '/';            /* restore "~user/..." */
 622                 if (entry)
 623                         home = entry->pw_dir;
 624         }
 625         if (home) {
 626                 ud = concat_path_file(home, ud);
 627                 free(tilde_name);
 628                 tilde_name = ud;
 629         }
 630         return tilde_name;
 631 }
 632
 633 /* ~use<tab> - find all users with this prefix.
 634  * Return the length of the prefix used for matching.
 635  */
 636 static NOINLINE unsigned complete_username(const char *ud)
 637 {
 638         /* Using _r function to avoid pulling in static buffers */
 639         char line_buff[256];
 640         struct passwd pwd;
 641         struct passwd *result;
 642         unsigned userlen;
 643
 644         ud++; /* skip ~ */
 645         userlen = strlen(ud);
 646
 647         setpwent();
 648         while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
 649                 /* Null usernames should result in all users as possible completions. */
 650                 if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
 651                         add_match(xasprintf("~%s/", pwd.pw_name));
 652                 }
 653         }
 654         endpwent();
 655
 656         return 1 + userlen;
 657 }
 658 #endif  /* FEATURE_USERNAME_COMPLETION */
 659
 660 enum {
 661         FIND_EXE_ONLY = 0,
 662         FIND_DIR_ONLY = 1,
 663         FIND_FILE_ONLY = 2,
 664 };
 665
 666 static int path_parse(char ***p)
 667 {
 668         int npth;
 669         const char *pth;
 670         char *tmp;
 671         char **res;
 672
 673         if (state->flags & WITH_PATH_LOOKUP)
 674                 pth = state->path_lookup;
 675         else
 676                 pth = getenv("PATH");
 677
 678         /* PATH="" or PATH=":"? */
 679         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 680                 return 1;
 681
 682         tmp = (char*)pth;
 683         npth = 1; /* path component count */
 684         while (1) {
 685                 tmp = strchr(tmp, ':');
 686                 if (!tmp)
 687                         break;
 688                 tmp++;
 689                 if (*tmp == '\0')
 690                         break;  /* :<empty> */
 691                 npth++;
 692         }
 693
 694         *p = res = xmalloc(npth * sizeof(res[0]));
 695         res[0] = tmp = xstrdup(pth);
 696         npth = 1;
 697         while (1) {
 698                 tmp = strchr(tmp, ':');
 699                 if (!tmp)
 700                         break;
 701                 *tmp++ = '\0'; /* ':' -> '\0' */
 702                 if (*tmp == '\0')
 703                         break; /* :<empty> */
 704                 res[npth++] = tmp;
 705         }
 706         return npth;
 707 }
 708
 709 /* Complete command, directory or file name.
 710  * Return the length of the prefix used for matching.
 711  */
 712 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 713 {
 714         char *path1[1];
 715         char **paths = path1;
 716         int npaths;
 717         int i;
 718         unsigned pf_len;
 719         const char *pfind;
 720         char *dirbuf = NULL;
 721
 722         npaths = 1;
 723         path1[0] = (char*)".";
 724
 725         pfind = strrchr(command, '/');
 726         if (!pfind) {
 727                 if (type == FIND_EXE_ONLY)
 728                         npaths = path_parse(&paths);
 729                 pfind = command;
 730         } else {
 731                 /* point to 'l' in "..../last_component" */
 732                 pfind++;
 733                 /* dirbuf = ".../.../.../" */
 734                 dirbuf = xstrndup(command, pfind - command);
 735 #if ENABLE_FEATURE_USERNAME_COMPLETION
 736                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 737                         dirbuf = username_path_completion(dirbuf);
 738 #endif
 739                 path1[0] = dirbuf;
 740         }
 741         pf_len = strlen(pfind);
 742
 743         for (i = 0; i < npaths; i++) {
 744                 DIR *dir;
 745                 struct dirent *next;
 746                 struct stat st;
 747                 char *found;
 748
 749                 dir = opendir(paths[i]);
 750                 if (!dir)
 751                         continue; /* don't print an error */
 752
 753                 while ((next = readdir(dir)) != NULL) {
 754                         const char *name_found = next->d_name;
 755
 756                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 757                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 758                                 continue;
 759                         /* match? */
 760                         if (strncmp(name_found, pfind, pf_len) != 0)
 761                                 continue; /* no */
 762
 763                         found = concat_path_file(paths[i], name_found);
 764                         /* NB: stat() first so that we see is it a directory;
 765                          * but if that fails, use lstat() so that
 766                          * we still match dangling links */
 767                         if (stat(found, &st) && lstat(found, &st))
 768                                 goto cont; /* hmm, remove in progress? */
 769
 770                         /* save only name if we scan PATH */
 771                         if (paths[i] != dirbuf)
 772                                 strcpy(found, name_found);
 773
 774                         if (S_ISDIR(st.st_mode)) {
 775                                 unsigned len1 = strlen(found);
 776                                 /* name is a directory */
 777                                 if (found[len1-1] != '/') {
 778                                         found = xrealloc(found, len1 + 2);
 779                                         found[len1] = '/';
 780                                         found[len1 + 1] = '\0';
 781                                 }
 782                         } else {
 783                                 /* skip files if looking for dirs only (example: cd) */
 784                                 if (type == FIND_DIR_ONLY)
 785                                         goto cont;
 786                         }
 787                         /* add it to the list */
 788                         add_match(found);
 789                         continue;
 790  cont:
 791                         free(found);
 792                 }
 793                 closedir(dir);
 794         } /* for every path */
 795
 796         if (paths != path1) {
 797                 free(paths[0]); /* allocated memory is only in first member */
 798                 free(paths);
 799         } else if (dirbuf) {
 800                 pf_len += strlen(dirbuf);
 801                 free(dirbuf);
 802         }
 803
 804         return pf_len;
 805 }
 806
 807 /* build_match_prefix:
 808  * On entry, match_buf contains everything up to cursor at the moment <tab>
 809  * was pressed. This function looks at it, figures out what part of it
 810  * constitutes the command/file/directory prefix to use for completion,
 811  * and rewrites match_buf to contain only that part.
 812  */
 813 #define dbg_bmp 0
 814 /* Helpers: */
 815 /* QUOT is used on elements of int_buf[], which are bytes,
 816  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 817  */
 818 #define QUOT (UCHAR_MAX+1)
 819 static void remove_chunk(int16_t *int_buf, int beg, int end)
 820 {
 821         /* beg must be <= end */
 822         if (beg == end)
 823                 return;
 824
 825         while ((int_buf[beg] = int_buf[end]) != 0)
 826                 beg++, end++;
 827
 828         if (dbg_bmp) {
 829                 int i;
 830                 for (i = 0; int_buf[i]; i++)
 831                         bb_putchar((unsigned char)int_buf[i]);
 832                 bb_putchar('\n');
 833         }
 834 }
 835 /* Caller ensures that match_buf points to a malloced buffer
 836  * big enough to hold strlen(match_buf)*2 + 2
 837  */
 838 static NOINLINE int build_match_prefix(char *match_buf)
 839 {
 840         int i, j;
 841         int command_mode;
 842         int16_t *int_buf = (int16_t*)match_buf;
 843
 844         if (dbg_bmp) printf("\n%s\n", match_buf);
 845
 846         /* Copy in reverse order, since they overlap */
 847         i = strlen(match_buf);
 848         do {
 849                 int_buf[i] = (unsigned char)match_buf[i];
 850                 i--;
 851         } while (i >= 0);
 852
 853         /* Mark every \c as "quoted c" */
 854         for (i = 0; int_buf[i]; i++) {
 855                 if (int_buf[i] == '\\') {
 856                         remove_chunk(int_buf, i, i + 1);
 857                         int_buf[i] |= QUOT;
 858                 }
 859         }
 860         /* Quote-mark "chars" and 'chars', drop delimiters */
 861         {
 862                 int in_quote = 0;
 863                 i = 0;
 864                 while (int_buf[i]) {
 865                         int cur = int_buf[i];
 866                         if (!cur)
 867                                 break;
 868                         if (cur == '\'' || cur == '"') {
 869                                 if (!in_quote || (cur == in_quote)) {
 870                                         in_quote ^= cur;
 871                                         remove_chunk(int_buf, i, i + 1);
 872                                         continue;
 873                                 }
 874                         }
 875                         if (in_quote)
 876                                 int_buf[i] = cur | QUOT;
 877                         i++;
 878                 }
 879         }
 880
 881         /* Remove everything up to command delimiters:
 882          * ';' ';;' '&' '|' '&&' '||',
 883          * but careful with '>&' '<&' '>|'
 884          */
 885         for (i = 0; int_buf[i]; i++) {
 886                 int cur = int_buf[i];
 887                 if (cur == ';' || cur == '&' || cur == '|') {
 888                         int prev = i ? int_buf[i - 1] : 0;
 889                         if (cur == '&' && (prev == '>' || prev == '<')) {
 890                                 continue;
 891                         } else if (cur == '|' && prev == '>') {
 892                                 continue;
 893                         }
 894                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 895                         i = -1;  /* back to square 1 */
 896                 }
 897         }
 898         /* Remove all `cmd` */
 899         for (i = 0; int_buf[i]; i++) {
 900                 if (int_buf[i] == '`') {
 901                         for (j = i + 1; int_buf[j]; j++) {
 902                                 if (int_buf[j] == '`') {
 903                                         /* `cmd` should count as a word:
 904                                          * `cmd` c<tab> should search for files c*,
 905                                          * not commands c*. Therefore we don't drop
 906                                          * `cmd` entirely, we replace it with single `.
 907                                          */
 908                                         remove_chunk(int_buf, i, j);
 909                                         goto next;
 910                                 }
 911                         }
 912                         /* No closing ` - command mode, remove all up to ` */
 913                         remove_chunk(int_buf, 0, i + 1);
 914                         break;
 915  next: ;
 916                 }
 917         }
 918
 919         /* Remove "cmd (" and "cmd {"
 920          * Example: "if { c<tab>"
 921          * In this example, c should be matched as command pfx.
 922          */
 923         for (i = 0; int_buf[i]; i++) {
 924                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 925                         remove_chunk(int_buf, 0, i + 1);
 926                         i = -1;  /* back to square 1 */
 927                 }
 928         }
 929
 930         /* Remove leading unquoted spaces */
 931         for (i = 0; int_buf[i]; i++)
 932                 if (int_buf[i] != ' ')
 933                         break;
 934         remove_chunk(int_buf, 0, i);
 935
 936         /* Determine completion mode */
 937         command_mode = FIND_EXE_ONLY;
 938         for (i = 0; int_buf[i]; i++) {
 939                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 940                         if (int_buf[i] == ' '
 941                          && command_mode == FIND_EXE_ONLY
 942                          && (char)int_buf[0] == 'c'
 943                          && (char)int_buf[1] == 'd'
 944                          && i == 2 /* -> int_buf[2] == ' ' */
 945                         ) {
 946                                 command_mode = FIND_DIR_ONLY;
 947                         } else {
 948                                 command_mode = FIND_FILE_ONLY;
 949                                 break;
 950                         }
 951                 }
 952         }
 953         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 954
 955         /* Remove everything except last word */
 956         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
 957                 continue;
 958         for (--i; i >= 0; i--) {
 959                 int cur = int_buf[i];
 960                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
 961                         remove_chunk(int_buf, 0, i + 1);
 962                         break;
 963                 }
 964         }
 965
 966         /* Convert back to string of _chars_ */
 967         i = 0;
 968         while ((match_buf[i] = int_buf[i]) != '\0')
 969                 i++;
 970
 971         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
 972
 973         return command_mode;
 974 }
 975
 976 /*
 977  * Display by column (original idea from ls applet,
 978  * very optimized by me [Vladimir] :)
 979  */
 980 static void showfiles(void)
 981 {
 982         int ncols, row;
 983         int column_width = 0;
 984         int nfiles = num_matches;
 985         int nrows = nfiles;
 986         int l;
 987
 988         /* find the longest file name - use that as the column width */
 989         for (row = 0; row < nrows; row++) {
 990                 l = unicode_strwidth(matches[row]);
 991                 if (column_width < l)
 992                         column_width = l;
 993         }
 994         column_width += 2;              /* min space for columns */
 995         ncols = cmdedit_termw / column_width;
 996
 997         if (ncols > 1) {
 998                 nrows /= ncols;
 999                 if (nfiles % ncols)
1000                         nrows++;        /* round up fractionals */
1001         } else {
1002                 ncols = 1;
1003         }
1004         for (row = 0; row < nrows; row++) {
1005                 int n = row;
1006                 int nc;
1007
1008                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1009                         printf("%s%-*s", matches[n],
1010                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1011                         );
1012                 }
1013                 if (ENABLE_UNICODE_SUPPORT)
1014                         puts(printable_string(NULL, matches[n]));
1015                 else
1016                         puts(matches[n]);
1017         }
1018 }
1019
1020 static char *add_quote_for_spec_chars(char *found)
1021 {
1022         int l = 0;
1023         char *s = xzalloc((strlen(found) + 1) * 2);
1024
1025         while (*found) {
1026                 if (strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", *found))
1027                         s[l++] = '\\';
1028                 s[l++] = *found++;
1029         }
1030         /* s[l] = '\0'; - already is */
1031         return s;
1032 }
1033
1034 /* Do TAB completion */
1035 static NOINLINE void input_tab(smallint *lastWasTab)
1036 {
1037         char *chosen_match;
1038         char *match_buf;
1039         size_t len_found;
1040         /* Length of string used for matching */
1041         unsigned match_pfx_len = match_pfx_len;
1042         int find_type;
1043 #if ENABLE_UNICODE_SUPPORT
1044         /* cursor pos in command converted to multibyte form */
1045         int cursor_mb;
1046 #endif
1047         if (!(state->flags & TAB_COMPLETION))
1048                 return;
1049
1050         if (*lastWasTab) {
1051                 /* The last char was a TAB too.
1052                  * Print a list of all the available choices.
1053                  */
1054                 if (num_matches > 0) {
1055                         /* cursor will be changed by goto_new_line() */
1056                         int sav_cursor = cursor;
1057                         goto_new_line();
1058                         showfiles();
1059                         redraw(0, command_len - sav_cursor);
1060                 }
1061                 return;
1062         }
1063
1064         *lastWasTab = 1;
1065         chosen_match = NULL;
1066
1067         /* Make a local copy of the string up to the position of the cursor.
1068          * build_match_prefix will expand it into int16_t's, need to allocate
1069          * twice as much as the string_len+1.
1070          * (we then also (ab)use this extra space later - see (**))
1071          */
1072         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1073 #if !ENABLE_UNICODE_SUPPORT
1074         save_string(match_buf, cursor + 1); /* +1 for NUL */
1075 #else
1076         {
1077                 CHAR_T wc = command_ps[cursor];
1078                 command_ps[cursor] = BB_NUL;
1079                 save_string(match_buf, MAX_LINELEN);
1080                 command_ps[cursor] = wc;
1081                 cursor_mb = strlen(match_buf);
1082         }
1083 #endif
1084         find_type = build_match_prefix(match_buf);
1085
1086         /* Free up any memory already allocated */
1087         free_tab_completion_data();
1088
1089 #if ENABLE_FEATURE_USERNAME_COMPLETION
1090         /* If the word starts with `~' and there is no slash in the word,
1091          * then try completing this word as a username. */
1092         if (state->flags & USERNAME_COMPLETION)
1093                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1094                         match_pfx_len = complete_username(match_buf);
1095 #endif
1096         /* Try to match a command in $PATH, or a directory, or a file */
1097         if (!matches)
1098                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1099         /* Remove duplicates */
1100         if (matches) {
1101                 unsigned i;
1102                 unsigned n = 0;
1103                 qsort_string_vector(matches, num_matches);
1104                 for (i = 0; i < num_matches - 1; ++i) {
1105                         //if (matches[i] && matches[i+1]) { /* paranoia */
1106                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1107                                         free(matches[i]);
1108                                         //matches[i] = NULL; /* paranoia */
1109                                 } else {
1110                                         matches[n++] = matches[i];
1111                                 }
1112                         //}
1113                 }
1114                 matches[n++] = matches[i];
1115                 num_matches = n;
1116         }
1117         /* Did we find exactly one match? */
1118         if (num_matches != 1) { /* no */
1119                 char *cp;
1120                 beep();
1121                 if (!matches)
1122                         goto ret; /* no matches at all */
1123                 /* Find common prefix */
1124                 chosen_match = xstrdup(matches[0]);
1125                 for (cp = chosen_match; *cp; cp++) {
1126                         unsigned n;
1127                         for (n = 1; n < num_matches; n++) {
1128                                 if (matches[n][cp - chosen_match] != *cp) {
1129                                         goto stop;
1130                                 }
1131                         }
1132                 }
1133  stop:
1134                 if (cp == chosen_match) { /* have unique prefix? */
1135                         goto ret; /* no */
1136                 }
1137                 *cp = '\0';
1138                 cp = add_quote_for_spec_chars(chosen_match);
1139                 free(chosen_match);
1140                 chosen_match = cp;
1141                 len_found = strlen(chosen_match);
1142         } else {                        /* exactly one match */
1143                 /* Next <tab> is not a double-tab */
1144                 *lastWasTab = 0;
1145
1146                 chosen_match = add_quote_for_spec_chars(matches[0]);
1147                 len_found = strlen(chosen_match);
1148                 if (chosen_match[len_found-1] != '/') {
1149                         chosen_match[len_found] = ' ';
1150                         chosen_match[++len_found] = '\0';
1151                 }
1152         }
1153
1154 #if !ENABLE_UNICODE_SUPPORT
1155         /* Have space to place the match? */
1156         /* The result consists of three parts with these lengths: */
1157         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1158         /* it simplifies into: */
1159         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1160                 int pos;
1161                 /* save tail */
1162                 strcpy(match_buf, &command_ps[cursor]);
1163                 /* add match and tail */
1164                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1165                 command_len = strlen(command_ps);
1166                 /* new pos */
1167                 pos = cursor + len_found - match_pfx_len;
1168                 /* write out the matched command */
1169                 redraw(cmdedit_y, command_len - pos);
1170         }
1171 #else
1172         {
1173                 /* Use 2nd half of match_buf as scratch space - see (**) */
1174                 char *command = match_buf + MAX_LINELEN;
1175                 int len = save_string(command, MAX_LINELEN);
1176                 /* Have space to place the match? */
1177                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1178                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1179                         int pos;
1180                         /* save tail */
1181                         strcpy(match_buf, &command[cursor_mb]);
1182                         /* where do we want to have cursor after all? */
1183                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1184                         len = load_string(command, S.maxsize);
1185                         /* add match and tail */
1186                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1187                         command_len = load_string(command, S.maxsize);
1188                         /* write out the matched command */
1189                         /* paranoia: load_string can return 0 on conv error,
1190                          * prevent passing pos = (0 - 12) to redraw */
1191                         pos = command_len - len;
1192                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1193                 }
1194         }
1195 #endif
1196  ret:
1197         free(chosen_match);
1198         free(match_buf);
1199 }
1200
1201 #endif  /* FEATURE_TAB_COMPLETION */
1202
1203
1204 line_input_t* FAST_FUNC new_line_input_t(int flags)
1205 {
1206         line_input_t *n = xzalloc(sizeof(*n));
1207         n->flags = flags;
1208         return n;
1209 }
1210
1211
1212 #if MAX_HISTORY > 0
1213
1214 static void save_command_ps_at_cur_history(void)
1215 {
1216         if (command_ps[0] != BB_NUL) {
1217                 int cur = state->cur_history;
1218                 free(state->history[cur]);
1219
1220 # if ENABLE_UNICODE_SUPPORT
1221                 {
1222                         char tbuf[MAX_LINELEN];
1223                         save_string(tbuf, sizeof(tbuf));
1224                         state->history[cur] = xstrdup(tbuf);
1225                 }
1226 # else
1227                 state->history[cur] = xstrdup(command_ps);
1228 # endif
1229         }
1230 }
1231
1232 /* state->flags is already checked to be nonzero */
1233 static int get_previous_history(void)
1234 {
1235         if ((state->flags & DO_HISTORY) && state->cur_history) {
1236                 save_command_ps_at_cur_history();
1237                 state->cur_history--;
1238                 return 1;
1239         }
1240         beep();
1241         return 0;
1242 }
1243
1244 static int get_next_history(void)
1245 {
1246         if (state->flags & DO_HISTORY) {
1247                 if (state->cur_history < state->cnt_history) {
1248                         save_command_ps_at_cur_history(); /* save the current history line */
1249                         return ++state->cur_history;
1250                 }
1251         }
1252         beep();
1253         return 0;
1254 }
1255
1256 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1257 /* We try to ensure that concurrent additions to the history
1258  * do not overwrite each other.
1259  * Otherwise shell users get unhappy.
1260  *
1261  * History file is trimmed lazily, when it grows several times longer
1262  * than configured MAX_HISTORY lines.
1263  */
1264
1265 static void free_line_input_t(line_input_t *n)
1266 {
1267         int i = n->cnt_history;
1268         while (i > 0)
1269                 free(n->history[--i]);
1270         free(n);
1271 }
1272
1273 /* state->flags is already checked to be nonzero */
1274 static void load_history(line_input_t *st_parm)
1275 {
1276         char *temp_h[MAX_HISTORY];
1277         char *line;
1278         FILE *fp;
1279         unsigned idx, i, line_len;
1280
1281         /* NB: do not trash old history if file can't be opened */
1282
1283         fp = fopen_for_read(st_parm->hist_file);
1284         if (fp) {
1285                 /* clean up old history */
1286                 for (idx = st_parm->cnt_history; idx > 0;) {
1287                         idx--;
1288                         free(st_parm->history[idx]);
1289                         st_parm->history[idx] = NULL;
1290                 }
1291
1292                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1293                 memset(temp_h, 0, sizeof(temp_h));
1294                 st_parm->cnt_history_in_file = idx = 0;
1295                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1296                         if (line[0] == '\0') {
1297                                 free(line);
1298                                 continue;
1299                         }
1300                         free(temp_h[idx]);
1301                         temp_h[idx] = line;
1302                         st_parm->cnt_history_in_file++;
1303                         idx++;
1304                         if (idx == MAX_HISTORY)
1305                                 idx = 0;
1306                 }
1307                 fclose(fp);
1308
1309                 /* find first non-NULL temp_h[], if any */
1310                 if (st_parm->cnt_history_in_file) {
1311                         while (temp_h[idx] == NULL) {
1312                                 idx++;
1313                                 if (idx == MAX_HISTORY)
1314                                         idx = 0;
1315                         }
1316                 }
1317
1318                 /* copy temp_h[] to st_parm->history[] */
1319                 for (i = 0; i < MAX_HISTORY;) {
1320                         line = temp_h[idx];
1321                         if (!line)
1322                                 break;
1323                         idx++;
1324                         if (idx == MAX_HISTORY)
1325                                 idx = 0;
1326                         line_len = strlen(line);
1327                         if (line_len >= MAX_LINELEN)
1328                                 line[MAX_LINELEN-1] = '\0';
1329                         st_parm->history[i++] = line;
1330                 }
1331                 st_parm->cnt_history = i;
1332         }
1333 }
1334
1335 /* state->flags is already checked to be nonzero */
1336 static void save_history(char *str)
1337 {
1338         int fd;
1339         int len, len2;
1340
1341         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0666);
1342         if (fd < 0)
1343                 return;
1344         xlseek(fd, 0, SEEK_END); /* paranoia */
1345         len = strlen(str);
1346         str[len] = '\n'; /* we (try to) do atomic write */
1347         len2 = full_write(fd, str, len + 1);
1348         str[len] = '\0';
1349         close(fd);
1350         if (len2 != len + 1)
1351                 return; /* "wtf?" */
1352
1353         /* did we write so much that history file needs trimming? */
1354         state->cnt_history_in_file++;
1355         if (state->cnt_history_in_file > MAX_HISTORY * 4) {
1356                 FILE *fp;
1357                 char *new_name;
1358                 line_input_t *st_temp;
1359                 int i;
1360
1361                 /* we may have concurrently written entries from others.
1362                  * load them */
1363                 st_temp = new_line_input_t(state->flags);
1364                 st_temp->hist_file = state->hist_file;
1365                 load_history(st_temp);
1366
1367                 /* write out temp file and replace hist_file atomically */
1368                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1369                 fp = fopen_for_write(new_name);
1370                 if (fp) {
1371                         for (i = 0; i < st_temp->cnt_history; i++)
1372                                 fprintf(fp, "%s\n", st_temp->history[i]);
1373                         fclose(fp);
1374                         if (rename(new_name, state->hist_file) == 0)
1375                                 state->cnt_history_in_file = st_temp->cnt_history;
1376                 }
1377                 free(new_name);
1378                 free_line_input_t(st_temp);
1379         }
1380 }
1381 # else
1382 #  define load_history(a) ((void)0)
1383 #  define save_history(a) ((void)0)
1384 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1385
1386 static void remember_in_history(char *str)
1387 {
1388         int i;
1389
1390         if (!(state->flags & DO_HISTORY))
1391                 return;
1392         if (str[0] == '\0')
1393                 return;
1394         i = state->cnt_history;
1395         /* Don't save dupes */
1396         if (i && strcmp(state->history[i-1], str) == 0)
1397                 return;
1398
1399         free(state->history[MAX_HISTORY]); /* redundant, paranoia */
1400         state->history[MAX_HISTORY] = NULL; /* redundant, paranoia */
1401
1402         /* If history[] is full, remove the oldest command */
1403         /* we need to keep history[MAX_HISTORY] empty, hence >=, not > */
1404         if (i >= MAX_HISTORY) {
1405                 free(state->history[0]);
1406                 for (i = 0; i < MAX_HISTORY-1; i++)
1407                         state->history[i] = state->history[i+1];
1408                 /* i == MAX_HISTORY-1 */
1409         }
1410         /* i <= MAX_HISTORY-1 */
1411         state->history[i++] = xstrdup(str);
1412         /* i <= MAX_HISTORY */
1413         state->cur_history = i;
1414         state->cnt_history = i;
1415 # if MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
1416         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1417                 save_history(str);
1418 # endif
1419         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines++;)
1420 }
1421
1422 #else /* MAX_HISTORY == 0 */
1423 # define remember_in_history(a) ((void)0)
1424 #endif /* MAX_HISTORY */
1425
1426
1427 #if ENABLE_FEATURE_EDITING_VI
1428 /*
1429  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1430  */
1431 static void
1432 vi_Word_motion(int eat)
1433 {
1434         CHAR_T *command = command_ps;
1435
1436         while (cursor < command_len && !BB_isspace(command[cursor]))
1437                 input_forward();
1438         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1439                 input_forward();
1440 }
1441
1442 static void
1443 vi_word_motion(int eat)
1444 {
1445         CHAR_T *command = command_ps;
1446
1447         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1448                 while (cursor < command_len
1449                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1450                 ) {
1451                         input_forward();
1452                 }
1453         } else if (BB_ispunct(command[cursor])) {
1454                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1455                         input_forward();
1456         }
1457
1458         if (cursor < command_len)
1459                 input_forward();
1460
1461         if (eat) {
1462                 while (cursor < command_len && BB_isspace(command[cursor]))
1463                         input_forward();
1464         }
1465 }
1466
1467 static void
1468 vi_End_motion(void)
1469 {
1470         CHAR_T *command = command_ps;
1471
1472         input_forward();
1473         while (cursor < command_len && BB_isspace(command[cursor]))
1474                 input_forward();
1475         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1476                 input_forward();
1477 }
1478
1479 static void
1480 vi_end_motion(void)
1481 {
1482         CHAR_T *command = command_ps;
1483
1484         if (cursor >= command_len-1)
1485                 return;
1486         input_forward();
1487         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1488                 input_forward();
1489         if (cursor >= command_len-1)
1490                 return;
1491         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1492                 while (cursor < command_len-1
1493                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1494                 ) {
1495                         input_forward();
1496                 }
1497         } else if (BB_ispunct(command[cursor])) {
1498                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1499                         input_forward();
1500         }
1501 }
1502
1503 static void
1504 vi_Back_motion(void)
1505 {
1506         CHAR_T *command = command_ps;
1507
1508         while (cursor > 0 && BB_isspace(command[cursor-1]))
1509                 input_backward(1);
1510         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1511                 input_backward(1);
1512 }
1513
1514 static void
1515 vi_back_motion(void)
1516 {
1517         CHAR_T *command = command_ps;
1518
1519         if (cursor <= 0)
1520                 return;
1521         input_backward(1);
1522         while (cursor > 0 && BB_isspace(command[cursor]))
1523                 input_backward(1);
1524         if (cursor <= 0)
1525                 return;
1526         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1527                 while (cursor > 0
1528                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1529                 ) {
1530                         input_backward(1);
1531                 }
1532         } else if (BB_ispunct(command[cursor])) {
1533                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1534                         input_backward(1);
1535         }
1536 }
1537 #endif
1538
1539 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1540 static void ctrl_left(void)
1541 {
1542         CHAR_T *command = command_ps;
1543
1544         while (1) {
1545                 CHAR_T c;
1546
1547                 input_backward(1);
1548                 if (cursor == 0)
1549                         break;
1550                 c = command[cursor];
1551                 if (c != ' ' && !BB_ispunct(c)) {
1552                         /* we reached a "word" delimited by spaces/punct.
1553                          * go to its beginning */
1554                         while (1) {
1555                                 c = command[cursor - 1];
1556                                 if (c == ' ' || BB_ispunct(c))
1557                                         break;
1558                                 input_backward(1);
1559                                 if (cursor == 0)
1560                                         break;
1561                         }
1562                         break;
1563                 }
1564         }
1565 }
1566 static void ctrl_right(void)
1567 {
1568         CHAR_T *command = command_ps;
1569
1570         while (1) {
1571                 CHAR_T c;
1572
1573                 c = command[cursor];
1574                 if (c == BB_NUL)
1575                         break;
1576                 if (c != ' ' && !BB_ispunct(c)) {
1577                         /* we reached a "word" delimited by spaces/punct.
1578                          * go to its end + 1 */
1579                         while (1) {
1580                                 input_forward();
1581                                 c = command[cursor];
1582                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1583                                         break;
1584                         }
1585                         break;
1586                 }
1587                 input_forward();
1588         }
1589 }
1590
1591
1592 /*
1593  * read_line_input and its helpers
1594  */
1595
1596 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1597 static void ask_terminal(void)
1598 {
1599         /* Ask terminal where is the cursor now.
1600          * lineedit_read_key handles response and corrects
1601          * our idea of current cursor position.
1602          * Testcase: run "echo -n long_line_long_line_long_line",
1603          * then type in a long, wrapping command and try to
1604          * delete it using backspace key.
1605          * Note: we print it _after_ prompt, because
1606          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1607          */
1608         /* Problem: if there is buffered input on stdin,
1609          * the response will be delivered later,
1610          * possibly to an unsuspecting application.
1611          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1612          * Result:
1613          * ~/srcdevel/bbox/fix/busybox.t4 #
1614          * ~/srcdevel/bbox/fix/busybox.t4 #
1615          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1616          * ~/srcdevel/bbox/fix/busybox.t4 #
1617          *
1618          * Checking for input with poll only makes the race narrower,
1619          * I still can trigger it. Strace:
1620          *
1621          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1622          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1623          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1624          * poll([{fd=0, events=POLLIN}], 1, 4294967295) = 1 ([{fd=0, revents=POLLIN}])
1625          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1626          */
1627         struct pollfd pfd;
1628
1629         pfd.fd = STDIN_FILENO;
1630         pfd.events = POLLIN;
1631         if (safe_poll(&pfd, 1, 0) == 0) {
1632                 S.sent_ESC_br6n = 1;
1633                 fputs("\033" "[6n", stdout);
1634                 fflush_all(); /* make terminal see it ASAP! */
1635         }
1636 }
1637 #else
1638 #define ask_terminal() ((void)0)
1639 #endif
1640
1641 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1642 static void parse_and_put_prompt(const char *prmt_ptr)
1643 {
1644         cmdedit_prompt = prmt_ptr;
1645         cmdedit_prmt_len = strlen(prmt_ptr);
1646         put_prompt();
1647 }
1648 #else
1649 static void parse_and_put_prompt(const char *prmt_ptr)
1650 {
1651         int prmt_len = 0;
1652         size_t cur_prmt_len = 0;
1653         char flg_not_length = '[';
1654         char *prmt_mem_ptr = xzalloc(1);
1655         char *cwd_buf = xrealloc_getcwd_or_warn(NULL);
1656         char cbuf[2];
1657         char c;
1658         char *pbuf;
1659
1660         cmdedit_prmt_len = 0;
1661
1662         if (!cwd_buf) {
1663                 cwd_buf = (char *)bb_msg_unknown;
1664         }
1665
1666         cbuf[1] = '\0'; /* never changes */
1667
1668         while (*prmt_ptr) {
1669                 char *free_me = NULL;
1670
1671                 pbuf = cbuf;
1672                 c = *prmt_ptr++;
1673                 if (c == '\\') {
1674                         const char *cp = prmt_ptr;
1675                         int l;
1676
1677                         c = bb_process_escape_sequence(&prmt_ptr);
1678                         if (prmt_ptr == cp) {
1679                                 if (*cp == '\0')
1680                                         break;
1681                                 c = *prmt_ptr++;
1682
1683                                 switch (c) {
1684 # if ENABLE_USERNAME_OR_HOMEDIR
1685                                 case 'u':
1686                                         pbuf = user_buf ? user_buf : (char*)"";
1687                                         break;
1688 # endif
1689                                 case 'h':
1690                                         pbuf = free_me = safe_gethostname();
1691                                         *strchrnul(pbuf, '.') = '\0';
1692                                         break;
1693                                 case '$':
1694                                         c = (geteuid() == 0 ? '#' : '$');
1695                                         break;
1696 # if ENABLE_USERNAME_OR_HOMEDIR
1697                                 case 'w':
1698                                         /* /home/user[/something] -> ~[/something] */
1699                                         pbuf = cwd_buf;
1700                                         l = strlen(home_pwd_buf);
1701                                         if (l != 0
1702                                          && strncmp(home_pwd_buf, cwd_buf, l) == 0
1703                                          && (cwd_buf[l]=='/' || cwd_buf[l]=='\0')
1704                                          && strlen(cwd_buf + l) < PATH_MAX
1705                                         ) {
1706                                                 pbuf = free_me = xasprintf("~%s", cwd_buf + l);
1707                                         }
1708                                         break;
1709 # endif
1710                                 case 'W':
1711                                         pbuf = cwd_buf;
1712                                         cp = strrchr(pbuf, '/');
1713                                         if (cp != NULL && cp != pbuf)
1714                                                 pbuf += (cp-pbuf) + 1;
1715                                         break;
1716                                 case '!':
1717                                         pbuf = free_me = xasprintf("%d", num_ok_lines);
1718                                         break;
1719                                 case 'e': case 'E':     /* \e \E = \033 */
1720                                         c = '\033';
1721                                         break;
1722                                 case 'x': case 'X': {
1723                                         char buf2[4];
1724                                         for (l = 0; l < 3;) {
1725                                                 unsigned h;
1726                                                 buf2[l++] = *prmt_ptr;
1727                                                 buf2[l] = '\0';
1728                                                 h = strtoul(buf2, &pbuf, 16);
1729                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1730                                                         buf2[--l] = '\0';
1731                                                         break;
1732                                                 }
1733                                                 prmt_ptr++;
1734                                         }
1735                                         c = (char)strtoul(buf2, NULL, 16);
1736                                         if (c == 0)
1737                                                 c = '?';
1738                                         pbuf = cbuf;
1739                                         break;
1740                                 }
1741                                 case '[': case ']':
1742                                         if (c == flg_not_length) {
1743                                                 flg_not_length = (flg_not_length == '[' ? ']' : '[');
1744                                                 continue;
1745                                         }
1746                                         break;
1747                                 } /* switch */
1748                         } /* if */
1749                 } /* if */
1750                 cbuf[0] = c;
1751                 cur_prmt_len = strlen(pbuf);
1752                 prmt_len += cur_prmt_len;
1753                 if (flg_not_length != ']')
1754                         cmdedit_prmt_len += cur_prmt_len;
1755                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_len+1), pbuf);
1756                 free(free_me);
1757         } /* while */
1758
1759         if (cwd_buf != (char *)bb_msg_unknown)
1760                 free(cwd_buf);
1761         cmdedit_prompt = prmt_mem_ptr;
1762         put_prompt();
1763 }
1764 #endif
1765
1766 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1767 {
1768         cmdedit_termw = w;
1769         if (redraw_flg) {
1770                 /* new y for current cursor */
1771                 int new_y = (cursor + cmdedit_prmt_len) / w;
1772                 /* redraw */
1773                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1774                 fflush_all();
1775         }
1776 }
1777
1778 static void win_changed(int nsig)
1779 {
1780         int sv_errno = errno;
1781         unsigned width;
1782         get_terminal_width_height(0, &width, NULL);
1783         cmdedit_setwidth(width, nsig /* - just a yes/no flag */);
1784         if (nsig == SIGWINCH)
1785                 signal(SIGWINCH, win_changed); /* rearm ourself */
1786         errno = sv_errno;
1787 }
1788
1789 static int lineedit_read_key(char *read_key_buffer)
1790 {
1791         int64_t ic;
1792         int timeout = -1;
1793 #if ENABLE_UNICODE_SUPPORT
1794         char unicode_buf[MB_CUR_MAX + 1];
1795         int unicode_idx = 0;
1796 #endif
1797
1798         while (1) {
1799                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
1800                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
1801                  * insist on full MB_CUR_MAX buffer to declare input like
1802                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
1803                  *
1804                  * Note: read_key sets errno to 0 on success.
1805                  */
1806                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
1807                 if (errno) {
1808 #if ENABLE_UNICODE_SUPPORT
1809                         if (errno == EAGAIN && unicode_idx != 0)
1810                                 goto pushback;
1811 #endif
1812                         break;
1813                 }
1814
1815 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1816                 if ((int32_t)ic == KEYCODE_CURSOR_POS
1817                  && S.sent_ESC_br6n
1818                 ) {
1819                         S.sent_ESC_br6n = 0;
1820                         if (cursor == 0) { /* otherwise it may be bogus */
1821                                 int col = ((ic >> 32) & 0x7fff) - 1;
1822                                 if (col > cmdedit_prmt_len) {
1823                                         cmdedit_x += (col - cmdedit_prmt_len);
1824                                         while (cmdedit_x >= cmdedit_termw) {
1825                                                 cmdedit_x -= cmdedit_termw;
1826                                                 cmdedit_y++;
1827                                         }
1828                                 }
1829                         }
1830                         continue;
1831                 }
1832 #endif
1833
1834 #if ENABLE_UNICODE_SUPPORT
1835                 if (unicode_status == UNICODE_ON) {
1836                         wchar_t wc;
1837
1838                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
1839                                 break;
1840                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
1841
1842                         unicode_buf[unicode_idx++] = ic;
1843                         unicode_buf[unicode_idx] = '\0';
1844                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
1845                                 /* Not (yet?) a valid unicode char */
1846                                 if (unicode_idx < MB_CUR_MAX) {
1847                                         timeout = 50;
1848                                         continue;
1849                                 }
1850  pushback:
1851                                 /* Invalid sequence. Save all "bad bytes" except first */
1852                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
1853 # if !ENABLE_UNICODE_PRESERVE_BROKEN
1854                                 ic = CONFIG_SUBST_WCHAR;
1855 # else
1856                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
1857 # endif
1858                         } else {
1859                                 /* Valid unicode char, return its code */
1860                                 ic = wc;
1861                         }
1862                 }
1863 #endif
1864                 break;
1865         }
1866
1867         return ic;
1868 }
1869
1870 #if ENABLE_UNICODE_BIDI_SUPPORT
1871 static int isrtl_str(void)
1872 {
1873         int idx = cursor;
1874
1875         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
1876                 idx++;
1877         return unicode_bidi_isrtl(command_ps[idx]);
1878 }
1879 #else
1880 # define isrtl_str() 0
1881 #endif
1882
1883 /* leave out the "vi-mode"-only case labels if vi editing isn't
1884  * configured. */
1885 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
1886
1887 /* convert uppercase ascii to equivalent control char, for readability */
1888 #undef CTRL
1889 #define CTRL(a) ((a) & ~0x40)
1890
1891 /* maxsize must be >= 2.
1892  * Returns:
1893  * -1 on read errors or EOF, or on bare Ctrl-D,
1894  * 0  on ctrl-C (the line entered is still returned in 'command'),
1895  * >0 length of input string, including terminating '\n'
1896  */
1897 int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, line_input_t *st)
1898 {
1899         int len;
1900 #if ENABLE_FEATURE_TAB_COMPLETION
1901         smallint lastWasTab = 0;
1902 #endif
1903         smallint break_out = 0;
1904 #if ENABLE_FEATURE_EDITING_VI
1905         smallint vi_cmdmode = 0;
1906 #endif
1907         struct termios initial_settings;
1908         struct termios new_settings;
1909         char read_key_buffer[KEYCODE_BUFFER_SIZE];
1910
1911         INIT_S();
1912
1913         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
1914          || !(initial_settings.c_lflag & ECHO)
1915         ) {
1916                 /* Happens when e.g. stty -echo was run before */
1917                 parse_and_put_prompt(prompt);
1918                 /* fflush_all(); - done by parse_and_put_prompt */
1919                 if (fgets(command, maxsize, stdin) == NULL)
1920                         len = -1; /* EOF or error */
1921                 else
1922                         len = strlen(command);
1923                 DEINIT_S();
1924                 return len;
1925         }
1926
1927         init_unicode();
1928
1929 // FIXME: audit & improve this
1930         if (maxsize > MAX_LINELEN)
1931                 maxsize = MAX_LINELEN;
1932         S.maxsize = maxsize;
1933
1934         /* With null flags, no other fields are ever used */
1935         state = st ? st : (line_input_t*) &const_int_0;
1936 #if MAX_HISTORY > 0
1937 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1938         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1939                 if (state->cnt_history == 0)
1940                         load_history(state);
1941 # endif
1942         if (state->flags & DO_HISTORY)
1943                 state->cur_history = state->cnt_history;
1944 #endif
1945
1946         /* prepare before init handlers */
1947         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
1948         command_len = 0;
1949 #if ENABLE_UNICODE_SUPPORT
1950         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
1951 #else
1952         command_ps = command;
1953         command[0] = '\0';
1954 #endif
1955 #define command command_must_not_be_used
1956
1957         new_settings = initial_settings;
1958         new_settings.c_lflag &= ~ICANON;        /* unbuffered input */
1959         /* Turn off echoing and CTRL-C, so we can trap it */
1960         new_settings.c_lflag &= ~(ECHO | ECHONL | ISIG);
1961         /* Hmm, in linux c_cc[] is not parsed if ICANON is off */
1962         new_settings.c_cc[VMIN] = 1;
1963         new_settings.c_cc[VTIME] = 0;
1964         /* Turn off CTRL-C, so we can trap it */
1965 #ifndef _POSIX_VDISABLE
1966 # define _POSIX_VDISABLE '\0'
1967 #endif
1968         new_settings.c_cc[VINTR] = _POSIX_VDISABLE;
1969         tcsetattr_stdin_TCSANOW(&new_settings);
1970
1971         /* Now initialize things */
1972         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
1973         win_changed(0); /* do initial resizing */
1974 #if ENABLE_USERNAME_OR_HOMEDIR
1975         {
1976                 struct passwd *entry;
1977
1978                 entry = getpwuid(geteuid());
1979                 if (entry) {
1980                         user_buf = xstrdup(entry->pw_name);
1981                         home_pwd_buf = xstrdup(entry->pw_dir);
1982                 }
1983         }
1984 #endif
1985
1986 #if 0
1987         for (i = 0; i <= MAX_HISTORY; i++)
1988                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
1989         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
1990 #endif
1991
1992         /* Print out the command prompt, optionally ask where cursor is */
1993         parse_and_put_prompt(prompt);
1994         ask_terminal();
1995
1996         read_key_buffer[0] = 0;
1997         while (1) {
1998                 /*
1999                  * The emacs and vi modes share much of the code in the big
2000                  * command loop.  Commands entered when in vi's command mode
2001                  * (aka "escape mode") get an extra bit added to distinguish
2002                  * them - this keeps them from being self-inserted. This
2003                  * clutters the big switch a bit, but keeps all the code
2004                  * in one place.
2005                  */
2006                 enum {
2007                         VI_CMDMODE_BIT = 0x40000000,
2008                         /* 0x80000000 bit flags KEYCODE_xxx */
2009                 };
2010                 int32_t ic, ic_raw;
2011
2012                 fflush_all();
2013                 ic = ic_raw = lineedit_read_key(read_key_buffer);
2014
2015 #if ENABLE_FEATURE_EDITING_VI
2016                 newdelflag = 1;
2017                 if (vi_cmdmode) {
2018                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2019                          * change ic if it contains one of them: */
2020                         ic |= VI_CMDMODE_BIT;
2021                 }
2022 #endif
2023
2024                 switch (ic) {
2025                 case '\n':
2026                 case '\r':
2027                 vi_case('\n'|VI_CMDMODE_BIT:)
2028                 vi_case('\r'|VI_CMDMODE_BIT:)
2029                         /* Enter */
2030                         goto_new_line();
2031                         break_out = 1;
2032                         break;
2033                 case CTRL('A'):
2034                 vi_case('0'|VI_CMDMODE_BIT:)
2035                         /* Control-a -- Beginning of line */
2036                         input_backward(cursor);
2037                         break;
2038                 case CTRL('B'):
2039                 vi_case('h'|VI_CMDMODE_BIT:)
2040                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2041                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2042                         input_backward(1); /* Move back one character */
2043                         break;
2044                 case CTRL('E'):
2045                 vi_case('$'|VI_CMDMODE_BIT:)
2046                         /* Control-e -- End of line */
2047                         put_till_end_and_adv_cursor();
2048                         break;
2049                 case CTRL('F'):
2050                 vi_case('l'|VI_CMDMODE_BIT:)
2051                 vi_case(' '|VI_CMDMODE_BIT:)
2052                         input_forward(); /* Move forward one character */
2053                         break;
2054                 case '\b':   /* ^H */
2055                 case '\x7f': /* DEL */
2056                         if (!isrtl_str())
2057                                 input_backspace();
2058                         else
2059                                 input_delete(0);
2060                         break;
2061                 case KEYCODE_DELETE:
2062                         if (!isrtl_str())
2063                                 input_delete(0);
2064                         else
2065                                 input_backspace();
2066                         break;
2067 #if ENABLE_FEATURE_TAB_COMPLETION
2068                 case '\t':
2069                         input_tab(&lastWasTab);
2070                         break;
2071 #endif
2072                 case CTRL('K'):
2073                         /* Control-k -- clear to end of line */
2074                         command_ps[cursor] = BB_NUL;
2075                         command_len = cursor;
2076                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2077                         break;
2078                 case CTRL('L'):
2079                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2080                         /* Control-l -- clear screen */
2081                         printf("\033[H"); /* cursor to top,left */
2082                         redraw(0, command_len - cursor);
2083                         break;
2084 #if MAX_HISTORY > 0
2085                 case CTRL('N'):
2086                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2087                 vi_case('j'|VI_CMDMODE_BIT:)
2088                         /* Control-n -- Get next command in history */
2089                         if (get_next_history())
2090                                 goto rewrite_line;
2091                         break;
2092                 case CTRL('P'):
2093                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2094                 vi_case('k'|VI_CMDMODE_BIT:)
2095                         /* Control-p -- Get previous command from history */
2096                         if (get_previous_history())
2097                                 goto rewrite_line;
2098                         break;
2099 #endif
2100                 case CTRL('U'):
2101                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2102                         /* Control-U -- Clear line before cursor */
2103                         if (cursor) {
2104                                 command_len -= cursor;
2105                                 memmove(command_ps, command_ps + cursor,
2106                                         (command_len + 1) * sizeof(command_ps[0]));
2107                                 redraw(cmdedit_y, command_len);
2108                         }
2109                         break;
2110                 case CTRL('W'):
2111                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2112                         /* Control-W -- Remove the last word */
2113                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2114                                 input_backspace();
2115                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2116                                 input_backspace();
2117                         break;
2118
2119 #if ENABLE_FEATURE_EDITING_VI
2120                 case 'i'|VI_CMDMODE_BIT:
2121                         vi_cmdmode = 0;
2122                         break;
2123                 case 'I'|VI_CMDMODE_BIT:
2124                         input_backward(cursor);
2125                         vi_cmdmode = 0;
2126                         break;
2127                 case 'a'|VI_CMDMODE_BIT:
2128                         input_forward();
2129                         vi_cmdmode = 0;
2130                         break;
2131                 case 'A'|VI_CMDMODE_BIT:
2132                         put_till_end_and_adv_cursor();
2133                         vi_cmdmode = 0;
2134                         break;
2135                 case 'x'|VI_CMDMODE_BIT:
2136                         input_delete(1);
2137                         break;
2138                 case 'X'|VI_CMDMODE_BIT:
2139                         if (cursor > 0) {
2140                                 input_backward(1);
2141                                 input_delete(1);
2142                         }
2143                         break;
2144                 case 'W'|VI_CMDMODE_BIT:
2145                         vi_Word_motion(1);
2146                         break;
2147                 case 'w'|VI_CMDMODE_BIT:
2148                         vi_word_motion(1);
2149                         break;
2150                 case 'E'|VI_CMDMODE_BIT:
2151                         vi_End_motion();
2152                         break;
2153                 case 'e'|VI_CMDMODE_BIT:
2154                         vi_end_motion();
2155                         break;
2156                 case 'B'|VI_CMDMODE_BIT:
2157                         vi_Back_motion();
2158                         break;
2159                 case 'b'|VI_CMDMODE_BIT:
2160                         vi_back_motion();
2161                         break;
2162                 case 'C'|VI_CMDMODE_BIT:
2163                         vi_cmdmode = 0;
2164                         /* fall through */
2165                 case 'D'|VI_CMDMODE_BIT:
2166                         goto clear_to_eol;
2167
2168                 case 'c'|VI_CMDMODE_BIT:
2169                         vi_cmdmode = 0;
2170                         /* fall through */
2171                 case 'd'|VI_CMDMODE_BIT: {
2172                         int nc, sc;
2173
2174                         ic = lineedit_read_key(read_key_buffer);
2175                         if (errno) /* error */
2176                                 goto prepare_to_die;
2177                         if (ic == ic_raw) { /* "cc", "dd" */
2178                                 input_backward(cursor);
2179                                 goto clear_to_eol;
2180                                 break;
2181                         }
2182
2183                         sc = cursor;
2184                         switch (ic) {
2185                         case 'w':
2186                         case 'W':
2187                         case 'e':
2188                         case 'E':
2189                                 switch (ic) {
2190                                 case 'w':   /* "dw", "cw" */
2191                                         vi_word_motion(vi_cmdmode);
2192                                         break;
2193                                 case 'W':   /* 'dW', 'cW' */
2194                                         vi_Word_motion(vi_cmdmode);
2195                                         break;
2196                                 case 'e':   /* 'de', 'ce' */
2197                                         vi_end_motion();
2198                                         input_forward();
2199                                         break;
2200                                 case 'E':   /* 'dE', 'cE' */
2201                                         vi_End_motion();
2202                                         input_forward();
2203                                         break;
2204                                 }
2205                                 nc = cursor;
2206                                 input_backward(cursor - sc);
2207                                 while (nc-- > cursor)
2208                                         input_delete(1);
2209                                 break;
2210                         case 'b':  /* "db", "cb" */
2211                         case 'B':  /* implemented as B */
2212                                 if (ic == 'b')
2213                                         vi_back_motion();
2214                                 else
2215                                         vi_Back_motion();
2216                                 while (sc-- > cursor)
2217                                         input_delete(1);
2218                                 break;
2219                         case ' ':  /* "d ", "c " */
2220                                 input_delete(1);
2221                                 break;
2222                         case '$':  /* "d$", "c$" */
2223  clear_to_eol:
2224                                 while (cursor < command_len)
2225                                         input_delete(1);
2226                                 break;
2227                         }
2228                         break;
2229                 }
2230                 case 'p'|VI_CMDMODE_BIT:
2231                         input_forward();
2232                         /* fallthrough */
2233                 case 'P'|VI_CMDMODE_BIT:
2234                         put();
2235                         break;
2236                 case 'r'|VI_CMDMODE_BIT:
2237 //FIXME: unicode case?
2238                         ic = lineedit_read_key(read_key_buffer);
2239                         if (errno) /* error */
2240                                 goto prepare_to_die;
2241                         if (ic < ' ' || ic > 255) {
2242                                 beep();
2243                         } else {
2244                                 command_ps[cursor] = ic;
2245                                 bb_putchar(ic);
2246                                 bb_putchar('\b');
2247                         }
2248                         break;
2249                 case '\x1b': /* ESC */
2250                         if (state->flags & VI_MODE) {
2251                                 /* insert mode --> command mode */
2252                                 vi_cmdmode = 1;
2253                                 input_backward(1);
2254                         }
2255                         break;
2256 #endif /* FEATURE_COMMAND_EDITING_VI */
2257
2258 #if MAX_HISTORY > 0
2259                 case KEYCODE_UP:
2260                         if (get_previous_history())
2261                                 goto rewrite_line;
2262                         beep();
2263                         break;
2264                 case KEYCODE_DOWN:
2265                         if (!get_next_history())
2266                                 break;
2267  rewrite_line:
2268                         /* Rewrite the line with the selected history item */
2269                         /* change command */
2270                         command_len = load_string(state->history[state->cur_history] ?
2271                                         state->history[state->cur_history] : "", maxsize);
2272                         /* redraw and go to eol (bol, in vi) */
2273                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2274                         break;
2275 #endif
2276                 case KEYCODE_RIGHT:
2277                         input_forward();
2278                         break;
2279                 case KEYCODE_LEFT:
2280                         input_backward(1);
2281                         break;
2282                 case KEYCODE_CTRL_LEFT:
2283                         ctrl_left();
2284                         break;
2285                 case KEYCODE_CTRL_RIGHT:
2286                         ctrl_right();
2287                         break;
2288                 case KEYCODE_HOME:
2289                         input_backward(cursor);
2290                         break;
2291                 case KEYCODE_END:
2292                         put_till_end_and_adv_cursor();
2293                         break;
2294
2295                 default:
2296                         if (initial_settings.c_cc[VINTR] != 0
2297                          && ic_raw == initial_settings.c_cc[VINTR]
2298                         ) {
2299                                 /* Ctrl-C (usually) - stop gathering input */
2300                                 goto_new_line();
2301                                 command_len = 0;
2302                                 break_out = -1; /* "do not append '\n'" */
2303                                 break;
2304                         }
2305                         if (initial_settings.c_cc[VEOF] != 0
2306                          && ic_raw == initial_settings.c_cc[VEOF]
2307                         ) {
2308                                 /* Ctrl-D (usually) - delete one character,
2309                                  * or exit if len=0 and no chars to delete */
2310                                 if (command_len == 0) {
2311                                         errno = 0;
2312 #if ENABLE_FEATURE_EDITING_VI
2313  prepare_to_die:
2314 #endif
2315                                         break_out = command_len = -1;
2316                                         break;
2317                                 }
2318                                 input_delete(0);
2319                                 break;
2320                         }
2321 //                      /* Control-V -- force insert of next char */
2322 //                      if (c == CTRL('V')) {
2323 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2324 //                                      goto prepare_to_die;
2325 //                              if (c == 0) {
2326 //                                      beep();
2327 //                                      break;
2328 //                              }
2329 //                      }
2330                         if (ic < ' '
2331                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2332                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2333                         ) {
2334                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2335                                  * and vi mode ignores unexpected chars.
2336                                  * Otherwise, we are here if ic is a
2337                                  * control char or an unhandled ESC sequence,
2338                                  * which is also ignored.
2339                                  */
2340                                 break;
2341                         }
2342                         if ((int)command_len >= (maxsize - 2)) {
2343                                 /* Not enough space for the char and EOL */
2344                                 break;
2345                         }
2346
2347                         command_len++;
2348                         if (cursor == (command_len - 1)) {
2349                                 /* We are at the end, append */
2350                                 command_ps[cursor] = ic;
2351                                 command_ps[cursor + 1] = BB_NUL;
2352                                 put_cur_glyph_and_inc_cursor();
2353                                 if (unicode_bidi_isrtl(ic))
2354                                         input_backward(1);
2355                         } else {
2356                                 /* In the middle, insert */
2357                                 int sc = cursor;
2358
2359                                 memmove(command_ps + sc + 1, command_ps + sc,
2360                                         (command_len - sc) * sizeof(command_ps[0]));
2361                                 command_ps[sc] = ic;
2362                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2363                                 if (!isrtl_str())
2364                                         sc++; /* no */
2365                                 put_till_end_and_adv_cursor();
2366                                 /* to prev x pos + 1 */
2367                                 input_backward(cursor - sc);
2368                         }
2369                         break;
2370                 } /* switch (ic) */
2371
2372                 if (break_out)
2373                         break;
2374
2375 #if ENABLE_FEATURE_TAB_COMPLETION
2376                 if (ic_raw != '\t')
2377                         lastWasTab = 0;
2378 #endif
2379         } /* while (1) */
2380
2381 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2382         if (S.sent_ESC_br6n) {
2383                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2384                  * We sent "ESC [ 6 n", but got '\n' first, and
2385                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2386                  * It's bad already and not much can be done with it
2387                  * (it _will_ be visible for the next process to read stdin),
2388                  * but without this delay it even shows up on the screen
2389                  * as garbage because we restore echo settings with tcsetattr
2390                  * before it comes in. UGLY!
2391                  */
2392                 usleep(20*1000);
2393         }
2394 #endif
2395
2396 /* End of bug-catching "command_must_not_be_used" trick */
2397 #undef command
2398
2399 #if ENABLE_UNICODE_SUPPORT
2400         command[0] = '\0';
2401         if (command_len > 0)
2402                 command_len = save_string(command, maxsize - 1);
2403         free(command_ps);
2404 #endif
2405
2406         if (command_len > 0)
2407                 remember_in_history(command);
2408
2409         if (break_out > 0) {
2410                 command[command_len++] = '\n';
2411                 command[command_len] = '\0';
2412         }
2413
2414 #if ENABLE_FEATURE_TAB_COMPLETION
2415         free_tab_completion_data();
2416 #endif
2417
2418         /* restore initial_settings */
2419         tcsetattr_stdin_TCSANOW(&initial_settings);
2420         /* restore SIGWINCH handler */
2421         signal(SIGWINCH, previous_SIGWINCH_handler);
2422         fflush_all();
2423
2424         len = command_len;
2425         DEINIT_S();
2426
2427         return len; /* can't return command_len, DEINIT_S() destroys it */
2428 }
2429
2430 #else  /* !FEATURE_EDITING */
2431
2432 #undef read_line_input
2433 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2434 {
2435         fputs(prompt, stdout);
2436         fflush_all();
2437         fgets(command, maxsize, stdin);
2438         return strlen(command);
2439 }
2440
2441 #endif  /* !FEATURE_EDITING */
2442
2443
2444 /*
2445  * Testing
2446  */
2447
2448 #ifdef TEST
2449
2450 #include <locale.h>
2451
2452 const char *applet_name = "debug stuff usage";
2453
2454 int main(int argc, char **argv)
2455 {
2456         char buff[MAX_LINELEN];
2457         char *prompt =
2458 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2459                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2460                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2461                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2462 #else
2463                 "% ";
2464 #endif
2465
2466         while (1) {
2467                 int l;
2468                 l = read_line_input(prompt, buff);
2469                 if (l <= 0 || buff[l-1] != '\n')
2470                         break;
2471                 buff[l-1] = '\0';
2472                 printf("*** read_line_input() returned line =%s=\n", buff);
2473         }
2474         printf("*** read_line_input() detect ^D\n");
2475         return 0;
2476 }
2477
2478 #endif  /* TEST */