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