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