libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16 /*
  17  * Usage and known bugs:
  18  * Terminal key codes are not extensive, more needs to be added.
  19  * This version was created on Debian GNU/Linux 2.x.
  20  * Delete, Backspace, Home, End, and the arrow keys were tested
  21  * to work in an Xterm and console. Ctrl-A also works as Home.
  22  * Ctrl-E also works as End.
  23  *
  24  * The following readline-like commands are not implemented:
  25  * CTL-t -- Transpose two characters
  26  *
  27  * lineedit does not know that the terminal escape sequences do not
  28  * take up space on the screen. The redisplay code assumes, unless
  29  * told otherwise, that each character in the prompt is a printable
  30  * character that takes up one character position on the screen.
  31  * You need to tell lineedit that some sequences of characters
  32  * in the prompt take up no screen space. Compatibly with readline,
  33  * use the \[ escape to begin a sequence of non-printing characters,
  34  * and the \] escape to signal the end of such a sequence. Example:
  35  *
  36  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  37  *
  38  * Unicode in PS1 is not fully supported: prompt length calulation is wrong,
  39  * resulting in line wrap problems with long (multi-line) input.
  40  */
  41 #include "busybox.h"
  42 #include "NUM_APPLETS.h"
  43 #include "unicode.h"
  44 #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)
  74 {
  75         return ((unsigned)c < 256 && isspace(c));
  76 }
  77 # if ENABLE_FEATURE_EDITING_VI
  78 static bool BB_isalnum_or_underscore(CHAR_T c)
  79 {
  80         return ((unsigned)c < 256 && isalnum(c)) || c == '_';
  81 }
  82 # endif
  83 static bool BB_ispunct(CHAR_T c)
  84 {
  85         return ((unsigned)c < 256 && ispunct(c));
  86 }
  87 # undef isspace
  88 # undef isalnum
  89 # undef ispunct
  90 # undef isprint
  91 # define isspace isspace_must_not_be_used
  92 # define isalnum isalnum_must_not_be_used
  93 # define ispunct ispunct_must_not_be_used
  94 # define isprint isprint_must_not_be_used
  95 #else
  96 # define BB_NUL '\0'
  97 # define CHAR_T char
  98 # define BB_isspace(c) isspace(c)
  99 # if ENABLE_FEATURE_EDITING_VI
 100 static bool BB_isalnum_or_underscore(CHAR_T c)
 101 {
 102         return isalnum(c) || c == '_';
 103 }
 104 # endif
 105 # define BB_ispunct(c) ispunct(c)
 106 #endif
 107 #if ENABLE_UNICODE_PRESERVE_BROKEN
 108 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
 109 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
 110 #else
 111 # define unicode_is_raw_byte(wc)     0
 112 #endif
 113
 114
 115 #define ESC "\033"
 116
 117 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 118 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 119
 120
 121 enum {
 122         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 123                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 124                       : 0x7ff0
 125 };
 126
 127 #if ENABLE_USERNAME_OR_HOMEDIR
 128 static const char null_str[] ALIGN1 = "";
 129 #endif
 130
 131 /* We try to minimize both static and stack usage. */
 132 struct lineedit_statics {
 133         line_input_t *state;
 134
 135         unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 136
 137         unsigned cmdedit_x;        /* real x (col) terminal position */
 138         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 139         unsigned cmdedit_prmt_len; /* on-screen length of last/sole prompt line */
 140
 141         unsigned cursor;
 142         int command_len; /* must be signed */
 143         /* signed maxsize: we want x in "if (x > S.maxsize)"
 144          * to _not_ be promoted to unsigned */
 145         int maxsize;
 146         CHAR_T *command_ps;
 147
 148         const char *cmdedit_prompt;
 149         const char *prompt_last_line;  /* last/sole prompt line */
 150
 151 #if ENABLE_USERNAME_OR_HOMEDIR
 152         char *user_buf;
 153         char *home_pwd_buf; /* = (char*)null_str; */
 154 #endif
 155
 156 #if ENABLE_FEATURE_TAB_COMPLETION
 157         char **matches;
 158         unsigned num_matches;
 159 #endif
 160
 161 #if ENABLE_FEATURE_EDITING_WINCH
 162         unsigned SIGWINCH_saved;
 163         volatile unsigned SIGWINCH_count;
 164         volatile smallint ok_to_redraw;
 165 #endif
 166
 167 #if ENABLE_FEATURE_EDITING_VI
 168 # define DELBUFSIZ 128
 169         smallint newdelflag;     /* whether delbuf should be reused yet */
 170         CHAR_T *delptr;
 171         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 172 #endif
 173 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 174         smallint sent_ESC_br6n;
 175 #endif
 176
 177 #if ENABLE_FEATURE_EDITING_WINCH
 178         /* Largish struct, keeping it last results in smaller code */
 179         struct sigaction SIGWINCH_handler;
 180 #endif
 181 };
 182
 183 /* See lineedit_ptr_hack.c */
 184 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 185
 186 #define S (*lineedit_ptr_to_statics)
 187 #define state            (S.state           )
 188 #define cmdedit_termw    (S.cmdedit_termw   )
 189 #define cmdedit_x        (S.cmdedit_x       )
 190 #define cmdedit_y        (S.cmdedit_y       )
 191 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 192 #define cursor           (S.cursor          )
 193 #define command_len      (S.command_len     )
 194 #define command_ps       (S.command_ps      )
 195 #define cmdedit_prompt   (S.cmdedit_prompt  )
 196 #define prompt_last_line (S.prompt_last_line)
 197 #define user_buf         (S.user_buf        )
 198 #define home_pwd_buf     (S.home_pwd_buf    )
 199 #define matches          (S.matches         )
 200 #define num_matches      (S.num_matches     )
 201 #define delptr           (S.delptr          )
 202 #define newdelflag       (S.newdelflag      )
 203 #define delbuf           (S.delbuf          )
 204
 205 #define INIT_S() do { \
 206         (*(struct lineedit_statics**)not_const_pp(&lineedit_ptr_to_statics)) = xzalloc(sizeof(S)); \
 207         barrier(); \
 208         cmdedit_termw = 80; \
 209         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 210         IF_FEATURE_EDITING_VI(delptr = delbuf;) \
 211 } while (0)
 212
 213 static void deinit_S(void)
 214 {
 215 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 216         /* This one is allocated only if FANCY_PROMPT is on
 217          * (otherwise it points to verbatim prompt (NOT malloced)) */
 218         free((char*)cmdedit_prompt);
 219 #endif
 220 #if ENABLE_USERNAME_OR_HOMEDIR
 221         free(user_buf);
 222         if (home_pwd_buf != null_str)
 223                 free(home_pwd_buf);
 224 #endif
 225         free(lineedit_ptr_to_statics);
 226 }
 227 #define DEINIT_S() deinit_S()
 228
 229
 230 #if ENABLE_UNICODE_SUPPORT
 231 static size_t load_string(const char *src)
 232 {
 233         if (unicode_status == UNICODE_ON) {
 234                 ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
 235                 if (len < 0)
 236                         len = 0;
 237                 command_ps[len] = BB_NUL;
 238                 return len;
 239         } else {
 240                 unsigned i = 0;
 241                 while (src[i] && i < S.maxsize - 1) {
 242                         command_ps[i] = src[i];
 243                         i++;
 244                 }
 245                 command_ps[i] = BB_NUL;
 246                 return i;
 247         }
 248 }
 249 static unsigned save_string(char *dst, unsigned maxsize)
 250 {
 251         if (unicode_status == UNICODE_ON) {
 252 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 253                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 254                 if (len < 0)
 255                         len = 0;
 256                 dst[len] = '\0';
 257                 return len;
 258 # else
 259                 unsigned dstpos = 0;
 260                 unsigned srcpos = 0;
 261
 262                 maxsize--;
 263                 while (dstpos < maxsize) {
 264                         wchar_t wc;
 265                         int n = srcpos;
 266
 267                         /* Convert up to 1st invalid byte (or up to end) */
 268                         while ((wc = command_ps[srcpos]) != BB_NUL
 269                             && !unicode_is_raw_byte(wc)
 270                         ) {
 271                                 srcpos++;
 272                         }
 273                         command_ps[srcpos] = BB_NUL;
 274                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 275                         if (n < 0) /* should not happen */
 276                                 break;
 277                         dstpos += n;
 278                         if (wc == BB_NUL) /* usually is */
 279                                 break;
 280
 281                         /* We do have invalid byte here! */
 282                         command_ps[srcpos] = wc; /* restore it */
 283                         srcpos++;
 284                         if (dstpos == maxsize)
 285                                 break;
 286                         dst[dstpos++] = (char) wc;
 287                 }
 288                 dst[dstpos] = '\0';
 289                 return dstpos;
 290 # endif
 291         } else {
 292                 unsigned i = 0;
 293                 while ((dst[i] = command_ps[i]) != 0)
 294                         i++;
 295                 return i;
 296         }
 297 }
 298 /* I thought just fputwc(c, stdout) would work. But no... */
 299 static void BB_PUTCHAR(wchar_t c)
 300 {
 301         if (unicode_status == UNICODE_ON) {
 302                 char buf[MB_CUR_MAX + 1];
 303                 mbstate_t mbst = { 0 };
 304                 ssize_t len = wcrtomb(buf, c, &mbst);
 305                 if (len > 0) {
 306                         buf[len] = '\0';
 307                         fputs(buf, stdout);
 308                 }
 309         } else {
 310                 /* In this case, c is always one byte */
 311                 putchar(c);
 312         }
 313 }
 314 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 315 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 316 # else
 317 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 318 #  define adjust_width_and_validate_wc(width_adj, wc) \
 319         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 320 # endif
 321 {
 322         int w = 1;
 323
 324         if (unicode_status == UNICODE_ON) {
 325                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 326                         /* note: also true for unicode_is_raw_byte(wc) */
 327                         goto subst;
 328                 }
 329                 w = wcwidth(wc);
 330                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 331                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 332                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 333                 ) {
 334  subst:
 335                         w = 1;
 336                         wc = CONFIG_SUBST_WCHAR;
 337                 }
 338         }
 339
 340 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 341         *width_adj += w;
 342 #endif
 343         return wc;
 344 }
 345 #else /* !UNICODE */
 346 static size_t load_string(const char *src)
 347 {
 348         safe_strncpy(command_ps, src, S.maxsize);
 349         return strlen(command_ps);
 350 }
 351 # if ENABLE_FEATURE_TAB_COMPLETION
 352 static void save_string(char *dst, unsigned maxsize)
 353 {
 354         safe_strncpy(dst, command_ps, maxsize);
 355 }
 356 # endif
 357 # define BB_PUTCHAR(c) bb_putchar(c)
 358 /* Should never be called: */
 359 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 360 #endif
 361
 362
 363 /* Put 'command_ps[cursor]', cursor++.
 364  * Advance cursor on screen. If we reached right margin, scroll text up
 365  * and remove terminal margin effect by printing 'next_char' */
 366 #define HACK_FOR_WRONG_WIDTH 1
 367 static void put_cur_glyph_and_inc_cursor(void)
 368 {
 369         CHAR_T c = command_ps[cursor];
 370         unsigned width = 0;
 371         int ofs_to_right;
 372
 373         if (c == BB_NUL) {
 374                 /* erase character after end of input string */
 375                 c = ' ';
 376         } else {
 377                 /* advance cursor only if we aren't at the end yet */
 378                 cursor++;
 379                 if (unicode_status == UNICODE_ON) {
 380                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 381                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 382                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 383                 } else {
 384                         cmdedit_x++;
 385                 }
 386         }
 387
 388         ofs_to_right = cmdedit_x - cmdedit_termw;
 389         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 390                 /* c fits on this line */
 391                 BB_PUTCHAR(c);
 392         }
 393
 394         if (ofs_to_right >= 0) {
 395                 /* we go to the next line */
 396 #if HACK_FOR_WRONG_WIDTH
 397                 /* This works better if our idea of term width is wrong
 398                  * and it is actually wider (often happens on serial lines).
 399                  * Printing CR,LF *forces* cursor to next line.
 400                  * OTOH if terminal width is correct AND terminal does NOT
 401                  * have automargin (IOW: it is moving cursor to next line
 402                  * by itself (which is wrong for VT-10x terminals)),
 403                  * this will break things: there will be one extra empty line */
 404                 puts("\r"); /* + implicit '\n' */
 405 #else
 406                 /* VT-10x terminals don't wrap cursor to next line when last char
 407                  * on the line is printed - cursor stays "over" this char.
 408                  * Need to print _next_ char too (first one to appear on next line)
 409                  * to make cursor move down to next line.
 410                  */
 411                 /* Works ok only if cmdedit_termw is correct. */
 412                 c = command_ps[cursor];
 413                 if (c == BB_NUL)
 414                         c = ' ';
 415                 BB_PUTCHAR(c);
 416                 bb_putchar('\b');
 417 #endif
 418                 cmdedit_y++;
 419                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 420                         width = 0;
 421                 } else { /* ofs_to_right > 0 */
 422                         /* wide char c didn't fit on prev line */
 423                         BB_PUTCHAR(c);
 424                 }
 425                 cmdedit_x = width;
 426         }
 427 }
 428
 429 /* Move to end of line (by printing all chars till the end) */
 430 static void put_till_end_and_adv_cursor(void)
 431 {
 432         while (cursor < command_len)
 433                 put_cur_glyph_and_inc_cursor();
 434 }
 435
 436 /* Go to the next line */
 437 static void goto_new_line(void)
 438 {
 439         put_till_end_and_adv_cursor();
 440         /* "cursor == 0" is only if prompt is "" and user input is empty */
 441         if (cursor == 0 || cmdedit_x != 0)
 442                 bb_putchar('\n');
 443 }
 444
 445 static void beep(void)
 446 {
 447         bb_putchar('\007');
 448 }
 449
 450 /* Full or last/sole prompt line, reset edit cursor, calculate terminal cursor.
 451  * cmdedit_y is always calculated for the last/sole prompt line.
 452  */
 453 static void put_prompt_custom(bool is_full)
 454 {
 455         fputs((is_full ? cmdedit_prompt : prompt_last_line), stdout);
 456         cursor = 0;
 457         cmdedit_y = cmdedit_prmt_len / cmdedit_termw; /* new quasireal y */
 458         cmdedit_x = cmdedit_prmt_len % cmdedit_termw;
 459 }
 460
 461 #define put_prompt_last_line() put_prompt_custom(0)
 462 #define put_prompt()           put_prompt_custom(1)
 463
 464 /* Move back one character */
 465 /* (optimized for slow terminals) */
 466 static void input_backward(unsigned num)
 467 {
 468         if (num > cursor)
 469                 num = cursor;
 470         if (num == 0)
 471                 return;
 472         cursor -= num;
 473
 474         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 475          && unicode_status == UNICODE_ON
 476         ) {
 477                 /* correct NUM to be equal to _screen_ width */
 478                 int n = num;
 479                 num = 0;
 480                 while (--n >= 0)
 481                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 482                 if (num == 0)
 483                         return;
 484         }
 485
 486         if (cmdedit_x >= num) {
 487                 cmdedit_x -= num;
 488                 if (num <= 4) {
 489                         /* This is longer by 5 bytes on x86.
 490                          * Also gets miscompiled for ARM users
 491                          * (busybox.net/bugs/view.php?id=2274).
 492                          * printf(("\b\b\b\b" + 4) - num);
 493                          * return;
 494                          */
 495                         do {
 496                                 bb_putchar('\b');
 497                         } while (--num);
 498                         return;
 499                 }
 500                 printf(ESC"[%uD", num);
 501                 return;
 502         }
 503
 504         /* Need to go one or more lines up */
 505         if (ENABLE_UNICODE_WIDE_WCHARS) {
 506                 /* With wide chars, it is hard to "backtrack"
 507                  * and reliably figure out where to put cursor.
 508                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 509                  * |prompt: <><> |
 510                  * |<><><><><><> |
 511                  * |_            |
 512                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 513                  * We need to go up one line, and then - how do we know that
 514                  * we need to go *10* positions to the right? Because
 515                  * |prompt: <>#<>|
 516                  * |<><><>#<><><>|
 517                  * |_            |
 518                  * in this situation we need to go *11* positions to the right.
 519                  *
 520                  * A simpler thing to do is to redraw everything from the start
 521                  * up to new cursor position (which is already known):
 522                  */
 523                 unsigned sv_cursor;
 524                 /* go to 1st column; go up to first line */
 525                 printf("\r" ESC"[%uA", cmdedit_y);
 526                 cmdedit_y = 0;
 527                 sv_cursor = cursor;
 528                 put_prompt_last_line(); /* sets cursor to 0 */
 529                 while (cursor < sv_cursor)
 530                         put_cur_glyph_and_inc_cursor();
 531         } else {
 532                 int lines_up;
 533                 /* num = chars to go back from the beginning of current line: */
 534                 num -= cmdedit_x;
 535                 /* num=1...w: one line up, w+1...2w: two, etc: */
 536                 lines_up = 1 + (num - 1) / cmdedit_termw;
 537                 cmdedit_x = (cmdedit_termw * cmdedit_y - num) % cmdedit_termw;
 538                 cmdedit_y -= lines_up;
 539                 /* go to 1st column; go up */
 540                 printf("\r" ESC"[%uA", lines_up);
 541                 /* go to correct column.
 542                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 543                  * need to *make sure* we skip it if cmdedit_x == 0 */
 544                 if (cmdedit_x)
 545                         printf(ESC"[%uC", cmdedit_x);
 546         }
 547 }
 548
 549 /* See redraw and draw_full below */
 550 static void draw_custom(int y, int back_cursor, bool is_full)
 551 {
 552         if (y > 0) /* up y lines */
 553                 printf(ESC"[%uA", y);
 554         bb_putchar('\r');
 555         put_prompt_custom(is_full);
 556         put_till_end_and_adv_cursor();
 557         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 558         input_backward(back_cursor);
 559 }
 560
 561 /* Move y lines up, draw last/sole prompt line, editor line[s], and clear tail.
 562  * goal: redraw the prompt+input+cursor in-place, overwriting the previous */
 563 #define redraw(y, back_cursor) draw_custom((y), (back_cursor), 0)
 564
 565 /* Like above, but without moving up, and while using all the prompt lines.
 566  * goal: draw a full prompt+input+cursor unrelated to a previous position.
 567  * note: cmdedit_y always ends up relating to the last/sole prompt line */
 568 #define draw_full(back_cursor) draw_custom(0, (back_cursor), 1)
 569
 570 /* Delete the char in front of the cursor, optionally saving it
 571  * for later putback */
 572 #if !ENABLE_FEATURE_EDITING_VI
 573 static void input_delete(void)
 574 #define input_delete(save) input_delete()
 575 #else
 576 static void input_delete(int save)
 577 #endif
 578 {
 579         int j = cursor;
 580
 581         if (j == (int)command_len)
 582                 return;
 583
 584 #if ENABLE_FEATURE_EDITING_VI
 585         if (save) {
 586                 if (newdelflag) {
 587                         delptr = delbuf;
 588                         newdelflag = 0;
 589                 }
 590                 if ((delptr - delbuf) < DELBUFSIZ)
 591                         *delptr++ = command_ps[j];
 592         }
 593 #endif
 594
 595         memmove(command_ps + j, command_ps + j + 1,
 596                         /* (command_len + 1 [because of NUL]) - (j + 1)
 597                          * simplified into (command_len - j) */
 598                         (command_len - j) * sizeof(command_ps[0]));
 599         command_len--;
 600         put_till_end_and_adv_cursor();
 601         /* Last char is still visible, erase it (and more) */
 602         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 603         input_backward(cursor - j);     /* back to old pos cursor */
 604 }
 605
 606 #if ENABLE_FEATURE_EDITING_VI
 607 static void put(void)
 608 {
 609         int ocursor;
 610         int j = delptr - delbuf;
 611
 612         if (j == 0)
 613                 return;
 614         ocursor = cursor;
 615         /* open hole and then fill it */
 616         memmove(command_ps + cursor + j, command_ps + cursor,
 617                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 618         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 619         command_len += j;
 620         put_till_end_and_adv_cursor();
 621         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 622 }
 623 #endif
 624
 625 /* Delete the char in back of the cursor */
 626 static void input_backspace(void)
 627 {
 628         if (cursor > 0) {
 629                 input_backward(1);
 630                 input_delete(0);
 631         }
 632 }
 633
 634 /* Move forward one character */
 635 static void input_forward(void)
 636 {
 637         if (cursor < command_len)
 638                 put_cur_glyph_and_inc_cursor();
 639 }
 640
 641 #if ENABLE_FEATURE_TAB_COMPLETION
 642
 643 //FIXME:
 644 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 645 //matches the file named "foo bar", which is untrue.
 646 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 647 //not "foo bar <cursor>...
 648
 649 static void free_tab_completion_data(void)
 650 {
 651         if (matches) {
 652                 while (num_matches)
 653                         free(matches[--num_matches]);
 654                 free(matches);
 655                 matches = NULL;
 656         }
 657 }
 658
 659 static void add_match(char *matched)
 660 {
 661         unsigned char *p = (unsigned char*)matched;
 662         while (*p) {
 663                 /* ESC attack fix: drop any string with control chars */
 664                 if (*p < ' '
 665                  || (!ENABLE_UNICODE_SUPPORT && *p >= 0x7f)
 666                  || (ENABLE_UNICODE_SUPPORT && *p == 0x7f)
 667                 ) {
 668                         free(matched);
 669                         return;
 670                 }
 671                 p++;
 672         }
 673         matches = xrealloc_vector(matches, 4, num_matches);
 674         matches[num_matches] = matched;
 675         num_matches++;
 676 }
 677
 678 # if ENABLE_FEATURE_USERNAME_COMPLETION
 679 /* Replace "~user/..." with "/homedir/...".
 680  * The parameter is malloced, free it or return it
 681  * unchanged if no user is matched.
 682  */
 683 static char *username_path_completion(char *ud)
 684 {
 685         struct passwd *entry;
 686         char *tilde_name = ud;
 687         char *home = NULL;
 688
 689         ud++; /* skip ~ */
 690         if (*ud == '/') {       /* "~/..." */
 691                 home = home_pwd_buf;
 692         } else {
 693                 /* "~user/..." */
 694                 ud = strchr(ud, '/');
 695                 *ud = '\0';           /* "~user" */
 696                 entry = getpwnam(tilde_name + 1);
 697                 *ud = '/';            /* restore "~user/..." */
 698                 if (entry)
 699                         home = entry->pw_dir;
 700         }
 701         if (home) {
 702                 ud = concat_path_file(home, ud);
 703                 free(tilde_name);
 704                 tilde_name = ud;
 705         }
 706         return tilde_name;
 707 }
 708
 709 /* ~use<tab> - find all users with this prefix.
 710  * Return the length of the prefix used for matching.
 711  */
 712 static NOINLINE unsigned complete_username(const char *ud)
 713 {
 714         struct passwd *pw;
 715         unsigned userlen;
 716
 717         ud++; /* skip ~ */
 718         userlen = strlen(ud);
 719
 720         setpwent();
 721         while ((pw = getpwent()) != NULL) {
 722                 /* Null usernames should result in all users as possible completions. */
 723                 if (/* !ud[0] || */ is_prefixed_with(pw->pw_name, ud)) {
 724                         add_match(xasprintf("~%s/", pw->pw_name));
 725                 }
 726         }
 727         endpwent(); /* don't keep password file open */
 728
 729         return 1 + userlen;
 730 }
 731 # endif  /* FEATURE_USERNAME_COMPLETION */
 732
 733 enum {
 734         FIND_EXE_ONLY = 0,
 735         FIND_DIR_ONLY = 1,
 736         FIND_FILE_ONLY = 2,
 737 };
 738
 739 static int path_parse(char ***p)
 740 {
 741         int npth;
 742         const char *pth;
 743         char *tmp;
 744         char **res;
 745
 746         if (state->flags & WITH_PATH_LOOKUP)
 747                 pth = state->path_lookup;
 748         else
 749                 pth = getenv("PATH");
 750
 751         /* PATH="" or PATH=":"? */
 752         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 753                 return 1;
 754
 755         tmp = (char*)pth;
 756         npth = 1; /* path component count */
 757         while (1) {
 758                 tmp = strchr(tmp, ':');
 759                 if (!tmp)
 760                         break;
 761                 tmp++;
 762                 if (*tmp == '\0')
 763                         break;  /* :<empty> */
 764                 npth++;
 765         }
 766
 767         *p = res = xmalloc(npth * sizeof(res[0]));
 768         res[0] = tmp = xstrdup(pth);
 769         npth = 1;
 770         while (1) {
 771                 tmp = strchr(tmp, ':');
 772                 if (!tmp)
 773                         break;
 774                 *tmp++ = '\0'; /* ':' -> '\0' */
 775                 if (*tmp == '\0')
 776                         break; /* :<empty> */
 777                 res[npth++] = tmp;
 778         }
 779         return npth;
 780 }
 781
 782 /* Complete command, directory or file name.
 783  * Return the length of the prefix used for matching.
 784  */
 785 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 786 {
 787         char *path1[1];
 788         char **paths = path1;
 789         int npaths;
 790         int i;
 791         unsigned pf_len;
 792         const char *pfind;
 793         char *dirbuf = NULL;
 794
 795         npaths = 1;
 796         path1[0] = (char*)".";
 797
 798         pfind = strrchr(command, '/');
 799         if (!pfind) {
 800                 if (type == FIND_EXE_ONLY)
 801                         npaths = path_parse(&paths);
 802                 pfind = command;
 803         } else {
 804                 /* point to 'l' in "..../last_component" */
 805                 pfind++;
 806                 /* dirbuf = ".../.../.../" */
 807                 dirbuf = xstrndup(command, pfind - command);
 808 # if ENABLE_FEATURE_USERNAME_COMPLETION
 809                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 810                         dirbuf = username_path_completion(dirbuf);
 811 # endif
 812                 path1[0] = dirbuf;
 813         }
 814         pf_len = strlen(pfind);
 815
 816         if (type == FIND_EXE_ONLY && !dirbuf) {
 817 # if ENABLE_FEATURE_SH_STANDALONE && NUM_APPLETS != 1
 818                 const char *p = applet_names;
 819                 while (*p) {
 820                         if (strncmp(pfind, p, pf_len) == 0)
 821                                 add_match(xstrdup(p));
 822                         while (*p++ != '\0')
 823                                 continue;
 824                 }
 825 # endif
 826 # if EDITING_HAS_get_exe_name
 827                 if (state->get_exe_name) {
 828                         i = 0;
 829                         for (;;) {
 830                                 const char *b = state->get_exe_name(i++);
 831                                 if (!b)
 832                                         break;
 833                                 if (strncmp(pfind, b, pf_len) == 0)
 834                                         add_match(xstrdup(b));
 835                         }
 836                 }
 837 # endif
 838         }
 839
 840         for (i = 0; i < npaths; i++) {
 841                 DIR *dir;
 842                 struct dirent *next;
 843                 struct stat st;
 844                 char *found;
 845
 846                 dir = opendir(paths[i]);
 847                 if (!dir)
 848                         continue; /* don't print an error */
 849
 850                 while ((next = readdir(dir)) != NULL) {
 851                         unsigned len;
 852                         const char *name_found = next->d_name;
 853
 854                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 855                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 856                                 continue;
 857                         /* match? */
 858                         if (!is_prefixed_with(name_found, pfind))
 859                                 continue; /* no */
 860
 861                         found = concat_path_file(paths[i], name_found);
 862                         /* NB: stat() first so that we see is it a directory;
 863                          * but if that fails, use lstat() so that
 864                          * we still match dangling links */
 865                         if (stat(found, &st) && lstat(found, &st))
 866                                 goto cont; /* hmm, remove in progress? */
 867
 868                         /* Save only name */
 869                         len = strlen(name_found);
 870                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 871                         strcpy(found, name_found);
 872
 873                         if (S_ISDIR(st.st_mode)) {
 874                                 /* name is a directory, add slash */
 875                                 found[len] = '/';
 876                                 found[len + 1] = '\0';
 877                         } else {
 878                                 /* skip files if looking for dirs only (example: cd) */
 879                                 if (type == FIND_DIR_ONLY)
 880                                         goto cont;
 881                         }
 882                         /* add it to the list */
 883                         add_match(found);
 884                         continue;
 885  cont:
 886                         free(found);
 887                 }
 888                 closedir(dir);
 889         } /* for every path */
 890
 891         if (paths != path1) {
 892                 free(paths[0]); /* allocated memory is only in first member */
 893                 free(paths);
 894         }
 895         free(dirbuf);
 896
 897         return pf_len;
 898 }
 899
 900 /* build_match_prefix:
 901  * On entry, match_buf contains everything up to cursor at the moment <tab>
 902  * was pressed. This function looks at it, figures out what part of it
 903  * constitutes the command/file/directory prefix to use for completion,
 904  * and rewrites match_buf to contain only that part.
 905  */
 906 #define dbg_bmp 0
 907 /* Helpers: */
 908 /* QUOT is used on elements of int_buf[], which are bytes,
 909  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 910  */
 911 #define QUOT (UCHAR_MAX+1)
 912 static void remove_chunk(int16_t *int_buf, int beg, int end)
 913 {
 914         /* beg must be <= end */
 915         if (beg == end)
 916                 return;
 917
 918         while ((int_buf[beg] = int_buf[end]) != 0)
 919                 beg++, end++;
 920
 921         if (dbg_bmp) {
 922                 int i;
 923                 for (i = 0; int_buf[i]; i++)
 924                         bb_putchar((unsigned char)int_buf[i]);
 925                 bb_putchar('\n');
 926         }
 927 }
 928 /* Caller ensures that match_buf points to a malloced buffer
 929  * big enough to hold strlen(match_buf)*2 + 2
 930  */
 931 static NOINLINE int build_match_prefix(char *match_buf)
 932 {
 933         int i, j;
 934         int command_mode;
 935         int16_t *int_buf = (int16_t*)match_buf;
 936
 937         if (dbg_bmp) printf("\n%s\n", match_buf);
 938
 939         /* Copy in reverse order, since they overlap */
 940         i = strlen(match_buf);
 941         do {
 942                 int_buf[i] = (unsigned char)match_buf[i];
 943                 i--;
 944         } while (i >= 0);
 945
 946         /* Mark every \c as "quoted c" */
 947         for (i = 0; int_buf[i]; i++) {
 948                 if (int_buf[i] == '\\') {
 949                         remove_chunk(int_buf, i, i + 1);
 950                         int_buf[i] |= QUOT;
 951                 }
 952         }
 953         /* Quote-mark "chars" and 'chars', drop delimiters */
 954         {
 955                 int in_quote = 0;
 956                 i = 0;
 957                 while (int_buf[i]) {
 958                         int cur = int_buf[i];
 959                         if (!cur)
 960                                 break;
 961                         if (cur == '\'' || cur == '"') {
 962                                 if (!in_quote || (cur == in_quote)) {
 963                                         in_quote ^= cur;
 964                                         remove_chunk(int_buf, i, i + 1);
 965                                         continue;
 966                                 }
 967                         }
 968                         if (in_quote)
 969                                 int_buf[i] = cur | QUOT;
 970                         i++;
 971                 }
 972         }
 973
 974         /* Remove everything up to command delimiters:
 975          * ';' ';;' '&' '|' '&&' '||',
 976          * but careful with '>&' '<&' '>|'
 977          */
 978         for (i = 0; int_buf[i]; i++) {
 979                 int cur = int_buf[i];
 980                 if (cur == ';' || cur == '&' || cur == '|') {
 981                         int prev = i ? int_buf[i - 1] : 0;
 982                         if (cur == '&' && (prev == '>' || prev == '<')) {
 983                                 continue;
 984                         } else if (cur == '|' && prev == '>') {
 985                                 continue;
 986                         }
 987                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 988                         i = -1;  /* back to square 1 */
 989                 }
 990         }
 991         /* Remove all `cmd` */
 992         for (i = 0; int_buf[i]; i++) {
 993                 if (int_buf[i] == '`') {
 994                         for (j = i + 1; int_buf[j]; j++) {
 995                                 if (int_buf[j] == '`') {
 996                                         /* `cmd` should count as a word:
 997                                          * `cmd` c<tab> should search for files c*,
 998                                          * not commands c*. Therefore we don't drop
 999                                          * `cmd` entirely, we replace it with single `.
1000                                          */
1001                                         remove_chunk(int_buf, i, j);
1002                                         goto next;
1003                                 }
1004                         }
1005                         /* No closing ` - command mode, remove all up to ` */
1006                         remove_chunk(int_buf, 0, i + 1);
1007                         break;
1008  next: ;
1009                 }
1010         }
1011
1012         /* Remove "cmd (" and "cmd {"
1013          * Example: "if { c<tab>"
1014          * In this example, c should be matched as command pfx.
1015          */
1016         for (i = 0; int_buf[i]; i++) {
1017                 if (int_buf[i] == '(' || int_buf[i] == '{') {
1018                         remove_chunk(int_buf, 0, i + 1);
1019                         i = -1;  /* back to square 1 */
1020                 }
1021         }
1022
1023         /* Remove leading unquoted spaces */
1024         for (i = 0; int_buf[i]; i++)
1025                 if (int_buf[i] != ' ')
1026                         break;
1027         remove_chunk(int_buf, 0, i);
1028
1029         /* Determine completion mode */
1030         command_mode = FIND_EXE_ONLY;
1031         for (i = 0; int_buf[i]; i++) {
1032                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
1033                         if (int_buf[i] == ' '
1034                          && command_mode == FIND_EXE_ONLY
1035                          && (char)int_buf[0] == 'c'
1036                          && (char)int_buf[1] == 'd'
1037                          && i == 2 /* -> int_buf[2] == ' ' */
1038                         ) {
1039                                 command_mode = FIND_DIR_ONLY;
1040                         } else {
1041                                 command_mode = FIND_FILE_ONLY;
1042                                 break;
1043                         }
1044                 }
1045         }
1046         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
1047
1048         /* Remove everything except last word */
1049         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
1050                 continue;
1051         for (--i; i >= 0; i--) {
1052                 int cur = int_buf[i];
1053                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
1054                         remove_chunk(int_buf, 0, i + 1);
1055                         break;
1056                 }
1057         }
1058
1059         /* Convert back to string of _chars_ */
1060         i = 0;
1061         while ((match_buf[i] = int_buf[i]) != '\0')
1062                 i++;
1063
1064         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
1065
1066         return command_mode;
1067 }
1068
1069 /*
1070  * Display by column (original idea from ls applet,
1071  * very optimized by me [Vladimir] :)
1072  */
1073 static void showfiles(void)
1074 {
1075         int ncols, row;
1076         int column_width = 0;
1077         int nfiles = num_matches;
1078         int nrows = nfiles;
1079         int l;
1080
1081         /* find the longest file name - use that as the column width */
1082         for (row = 0; row < nrows; row++) {
1083                 l = unicode_strwidth(matches[row]);
1084                 if (column_width < l)
1085                         column_width = l;
1086         }
1087         column_width += 2;              /* min space for columns */
1088         ncols = cmdedit_termw / column_width;
1089
1090         if (ncols > 1) {
1091                 nrows /= ncols;
1092                 if (nfiles % ncols)
1093                         nrows++;        /* round up fractionals */
1094         } else {
1095                 ncols = 1;
1096         }
1097         for (row = 0; row < nrows; row++) {
1098                 int n = row;
1099                 int nc;
1100
1101                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1102                         printf("%s%-*s", matches[n],
1103                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1104                         );
1105                 }
1106                 if (ENABLE_UNICODE_SUPPORT)
1107                         puts(printable_string(matches[n]));
1108                 else
1109                         puts(matches[n]);
1110         }
1111 }
1112
1113 static const char *is_special_char(char c)
1114 {
1115         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1116 }
1117
1118 static char *quote_special_chars(char *found)
1119 {
1120         int l = 0;
1121         char *s = xzalloc((strlen(found) + 1) * 2);
1122
1123         while (*found) {
1124                 if (is_special_char(*found))
1125                         s[l++] = '\\';
1126                 s[l++] = *found++;
1127         }
1128         /* s[l] = '\0'; - already is */
1129         return s;
1130 }
1131
1132 /* Do TAB completion */
1133 static NOINLINE void input_tab(smallint *lastWasTab)
1134 {
1135         char *chosen_match;
1136         char *match_buf;
1137         size_t len_found;
1138         /* Length of string used for matching */
1139         unsigned match_pfx_len = match_pfx_len;
1140         int find_type;
1141 # if ENABLE_UNICODE_SUPPORT
1142         /* cursor pos in command converted to multibyte form */
1143         int cursor_mb;
1144 # endif
1145         if (!(state->flags & TAB_COMPLETION))
1146                 return;
1147
1148         if (*lastWasTab) {
1149                 /* The last char was a TAB too.
1150                  * Print a list of all the available choices.
1151                  */
1152                 if (num_matches > 0) {
1153                         /* cursor will be changed by goto_new_line() */
1154                         int sav_cursor = cursor;
1155                         goto_new_line();
1156                         showfiles();
1157                         draw_full(command_len - sav_cursor);
1158                 }
1159                 return;
1160         }
1161
1162         *lastWasTab = 1;
1163         chosen_match = NULL;
1164
1165         /* Make a local copy of the string up to the position of the cursor.
1166          * build_match_prefix will expand it into int16_t's, need to allocate
1167          * twice as much as the string_len+1.
1168          * (we then also (ab)use this extra space later - see (**))
1169          */
1170         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1171 # if !ENABLE_UNICODE_SUPPORT
1172         save_string(match_buf, cursor + 1); /* +1 for NUL */
1173 # else
1174         {
1175                 CHAR_T wc = command_ps[cursor];
1176                 command_ps[cursor] = BB_NUL;
1177                 save_string(match_buf, MAX_LINELEN);
1178                 command_ps[cursor] = wc;
1179                 cursor_mb = strlen(match_buf);
1180         }
1181 # endif
1182         find_type = build_match_prefix(match_buf);
1183
1184         /* Free up any memory already allocated */
1185         free_tab_completion_data();
1186
1187 # if ENABLE_FEATURE_USERNAME_COMPLETION
1188         /* If the word starts with ~ and there is no slash in the word,
1189          * then try completing this word as a username. */
1190         if (state->flags & USERNAME_COMPLETION)
1191                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1192                         match_pfx_len = complete_username(match_buf);
1193 # endif
1194         /* If complete_username() did not match,
1195          * try to match a command in $PATH, or a directory, or a file */
1196         if (!matches)
1197                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1198
1199         /* Account for backslashes which will be inserted
1200          * by quote_special_chars() later */
1201         {
1202                 const char *e = match_buf + strlen(match_buf);
1203                 const char *s = e - match_pfx_len;
1204                 while (s < e)
1205                         if (is_special_char(*s++))
1206                                 match_pfx_len++;
1207         }
1208
1209         /* Remove duplicates */
1210         if (matches) {
1211                 unsigned i, n = 0;
1212                 qsort_string_vector(matches, num_matches);
1213                 for (i = 0; i < num_matches - 1; ++i) {
1214                         //if (matches[i] && matches[i+1]) { /* paranoia */
1215                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1216                                         free(matches[i]);
1217                                         //matches[i] = NULL; /* paranoia */
1218                                 } else {
1219                                         matches[n++] = matches[i];
1220                                 }
1221                         //}
1222                 }
1223                 matches[n++] = matches[i];
1224                 num_matches = n;
1225         }
1226
1227         /* Did we find exactly one match? */
1228         if (num_matches != 1) { /* no */
1229                 char *cp;
1230                 beep();
1231                 if (!matches)
1232                         goto ret; /* no matches at all */
1233                 /* Find common prefix */
1234                 chosen_match = xstrdup(matches[0]);
1235                 for (cp = chosen_match; *cp; cp++) {
1236                         unsigned n;
1237                         for (n = 1; n < num_matches; n++) {
1238                                 if (matches[n][cp - chosen_match] != *cp) {
1239                                         goto stop;
1240                                 }
1241                         }
1242                 }
1243  stop:
1244                 if (cp == chosen_match) { /* have unique prefix? */
1245                         goto ret; /* no */
1246                 }
1247                 *cp = '\0';
1248                 cp = quote_special_chars(chosen_match);
1249                 free(chosen_match);
1250                 chosen_match = cp;
1251                 len_found = strlen(chosen_match);
1252         } else {                        /* exactly one match */
1253                 /* Next <tab> is not a double-tab */
1254                 *lastWasTab = 0;
1255
1256                 chosen_match = quote_special_chars(matches[0]);
1257                 len_found = strlen(chosen_match);
1258                 if (chosen_match[len_found-1] != '/') {
1259                         chosen_match[len_found] = ' ';
1260                         chosen_match[++len_found] = '\0';
1261                 }
1262         }
1263
1264 # if !ENABLE_UNICODE_SUPPORT
1265         /* Have space to place the match? */
1266         /* The result consists of three parts with these lengths: */
1267         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1268         /* it simplifies into: */
1269         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1270                 int pos;
1271                 /* save tail */
1272                 strcpy(match_buf, &command_ps[cursor]);
1273                 /* add match and tail */
1274                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1275                 command_len = strlen(command_ps);
1276                 /* new pos */
1277                 pos = cursor + len_found - match_pfx_len;
1278                 /* write out the matched command */
1279                 redraw(cmdedit_y, command_len - pos);
1280         }
1281 # else
1282         {
1283                 /* Use 2nd half of match_buf as scratch space - see (**) */
1284                 char *command = match_buf + MAX_LINELEN;
1285                 int len = save_string(command, MAX_LINELEN);
1286                 /* Have space to place the match? */
1287                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1288                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1289                         int pos;
1290                         /* save tail */
1291                         strcpy(match_buf, &command[cursor_mb]);
1292                         /* where do we want to have cursor after all? */
1293                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1294                         len = load_string(command);
1295                         /* add match and tail */
1296                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1297                         command_len = load_string(command);
1298                         /* write out the matched command */
1299                         /* paranoia: load_string can return 0 on conv error,
1300                          * prevent passing pos = (0 - 12) to redraw */
1301                         pos = command_len - len;
1302                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1303                 }
1304         }
1305 # endif
1306  ret:
1307         free(chosen_match);
1308         free(match_buf);
1309 }
1310
1311 #endif  /* FEATURE_TAB_COMPLETION */
1312
1313
1314 line_input_t* FAST_FUNC new_line_input_t(int flags)
1315 {
1316         line_input_t *n = xzalloc(sizeof(*n));
1317         n->flags = flags;
1318         n->timeout = -1;
1319 #if MAX_HISTORY > 0
1320         n->max_history = MAX_HISTORY;
1321 #endif
1322         return n;
1323 }
1324
1325
1326 #if MAX_HISTORY > 0
1327
1328 unsigned FAST_FUNC size_from_HISTFILESIZE(const char *hp)
1329 {
1330         int size = MAX_HISTORY;
1331         if (hp) {
1332                 size = atoi(hp);
1333                 if (size <= 0)
1334                         return 1;
1335                 if (size > MAX_HISTORY)
1336                         return MAX_HISTORY;
1337         }
1338         return size;
1339 }
1340
1341 static void save_command_ps_at_cur_history(void)
1342 {
1343         if (command_ps[0] != BB_NUL) {
1344                 int cur = state->cur_history;
1345                 free(state->history[cur]);
1346
1347 # if ENABLE_UNICODE_SUPPORT
1348                 {
1349                         char tbuf[MAX_LINELEN];
1350                         save_string(tbuf, sizeof(tbuf));
1351                         state->history[cur] = xstrdup(tbuf);
1352                 }
1353 # else
1354                 state->history[cur] = xstrdup(command_ps);
1355 # endif
1356         }
1357 }
1358
1359 /* state->flags is already checked to be nonzero */
1360 static int get_previous_history(void)
1361 {
1362         if ((state->flags & DO_HISTORY) && state->cur_history) {
1363                 save_command_ps_at_cur_history();
1364                 state->cur_history--;
1365                 return 1;
1366         }
1367         beep();
1368         return 0;
1369 }
1370
1371 static int get_next_history(void)
1372 {
1373         if (state->flags & DO_HISTORY) {
1374                 if (state->cur_history < state->cnt_history) {
1375                         save_command_ps_at_cur_history(); /* save the current history line */
1376                         return ++state->cur_history;
1377                 }
1378         }
1379         beep();
1380         return 0;
1381 }
1382
1383 /* Lists command history. Used by shell 'history' builtins */
1384 void FAST_FUNC show_history(const line_input_t *st)
1385 {
1386         int i;
1387
1388         if (!st)
1389                 return;
1390         for (i = 0; i < st->cnt_history; i++)
1391                 printf("%4d %s\n", i, st->history[i]);
1392 }
1393
1394 void FAST_FUNC free_line_input_t(line_input_t *n)
1395 {
1396 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1397         int i = n->cnt_history;
1398         while (i > 0)
1399                 free(n->history[--i]);
1400 #endif
1401         free(n);
1402 }
1403
1404 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1405 /* We try to ensure that concurrent additions to the history
1406  * do not overwrite each other.
1407  * Otherwise shell users get unhappy.
1408  *
1409  * History file is trimmed lazily, when it grows several times longer
1410  * than configured MAX_HISTORY lines.
1411  */
1412
1413 /* state->flags is already checked to be nonzero */
1414 static void load_history(line_input_t *st_parm)
1415 {
1416         char *temp_h[MAX_HISTORY];
1417         char *line;
1418         FILE *fp;
1419         unsigned idx, i, line_len;
1420
1421         /* NB: do not trash old history if file can't be opened */
1422
1423         fp = fopen_for_read(st_parm->hist_file);
1424         if (fp) {
1425                 /* clean up old history */
1426                 for (idx = st_parm->cnt_history; idx > 0;) {
1427                         idx--;
1428                         free(st_parm->history[idx]);
1429                         st_parm->history[idx] = NULL;
1430                 }
1431
1432                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1433                 memset(temp_h, 0, sizeof(temp_h));
1434                 idx = 0;
1435                 st_parm->cnt_history_in_file = 0;
1436                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1437                         if (line[0] == '\0') {
1438                                 free(line);
1439                                 continue;
1440                         }
1441                         free(temp_h[idx]);
1442                         temp_h[idx] = line;
1443                         st_parm->cnt_history_in_file++;
1444                         idx++;
1445                         if (idx == st_parm->max_history)
1446                                 idx = 0;
1447                 }
1448                 fclose(fp);
1449
1450                 /* find first non-NULL temp_h[], if any */
1451                 if (st_parm->cnt_history_in_file) {
1452                         while (temp_h[idx] == NULL) {
1453                                 idx++;
1454                                 if (idx == st_parm->max_history)
1455                                         idx = 0;
1456                         }
1457                 }
1458
1459                 /* copy temp_h[] to st_parm->history[] */
1460                 for (i = 0; i < st_parm->max_history;) {
1461                         line = temp_h[idx];
1462                         if (!line)
1463                                 break;
1464                         idx++;
1465                         if (idx == st_parm->max_history)
1466                                 idx = 0;
1467                         line_len = strlen(line);
1468                         if (line_len >= MAX_LINELEN)
1469                                 line[MAX_LINELEN-1] = '\0';
1470                         st_parm->history[i++] = line;
1471                 }
1472                 st_parm->cnt_history = i;
1473                 if (ENABLE_FEATURE_EDITING_SAVE_ON_EXIT)
1474                         st_parm->cnt_history_in_file = i;
1475         }
1476 }
1477
1478 #  if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1479 void save_history(line_input_t *st)
1480 {
1481         FILE *fp;
1482
1483         if (!st->hist_file)
1484                 return;
1485         if (st->cnt_history <= st->cnt_history_in_file)
1486                 return;
1487
1488         fp = fopen(st->hist_file, "a");
1489         if (fp) {
1490                 int i, fd;
1491                 char *new_name;
1492                 line_input_t *st_temp;
1493
1494                 for (i = st->cnt_history_in_file; i < st->cnt_history; i++)
1495                         fprintf(fp, "%s\n", st->history[i]);
1496                 fclose(fp);
1497
1498                 /* we may have concurrently written entries from others.
1499                  * load them */
1500                 st_temp = new_line_input_t(st->flags);
1501                 st_temp->hist_file = st->hist_file;
1502                 st_temp->max_history = st->max_history;
1503                 load_history(st_temp);
1504
1505                 /* write out temp file and replace hist_file atomically */
1506                 new_name = xasprintf("%s.%u.new", st->hist_file, (int) getpid());
1507                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1508                 if (fd >= 0) {
1509                         fp = xfdopen_for_write(fd);
1510                         for (i = 0; i < st_temp->cnt_history; i++)
1511                                 fprintf(fp, "%s\n", st_temp->history[i]);
1512                         fclose(fp);
1513                         if (rename(new_name, st->hist_file) == 0)
1514                                 st->cnt_history_in_file = st_temp->cnt_history;
1515                 }
1516                 free(new_name);
1517                 free_line_input_t(st_temp);
1518         }
1519 }
1520 #  else
1521 static void save_history(char *str)
1522 {
1523         int fd;
1524         int len, len2;
1525
1526         if (!state->hist_file)
1527                 return;
1528
1529         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1530         if (fd < 0)
1531                 return;
1532         xlseek(fd, 0, SEEK_END); /* paranoia */
1533         len = strlen(str);
1534         str[len] = '\n'; /* we (try to) do atomic write */
1535         len2 = full_write(fd, str, len + 1);
1536         str[len] = '\0';
1537         close(fd);
1538         if (len2 != len + 1)
1539                 return; /* "wtf?" */
1540
1541         /* did we write so much that history file needs trimming? */
1542         state->cnt_history_in_file++;
1543         if (state->cnt_history_in_file > state->max_history * 4) {
1544                 char *new_name;
1545                 line_input_t *st_temp;
1546
1547                 /* we may have concurrently written entries from others.
1548                  * load them */
1549                 st_temp = new_line_input_t(state->flags);
1550                 st_temp->hist_file = state->hist_file;
1551                 st_temp->max_history = state->max_history;
1552                 load_history(st_temp);
1553
1554                 /* write out temp file and replace hist_file atomically */
1555                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1556                 fd = open(new_name, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1557                 if (fd >= 0) {
1558                         FILE *fp;
1559                         int i;
1560
1561                         fp = xfdopen_for_write(fd);
1562                         for (i = 0; i < st_temp->cnt_history; i++)
1563                                 fprintf(fp, "%s\n", st_temp->history[i]);
1564                         fclose(fp);
1565                         if (rename(new_name, state->hist_file) == 0)
1566                                 state->cnt_history_in_file = st_temp->cnt_history;
1567                 }
1568                 free(new_name);
1569                 free_line_input_t(st_temp);
1570         }
1571 }
1572 #  endif
1573 # else
1574 #  define load_history(a) ((void)0)
1575 #  define save_history(a) ((void)0)
1576 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1577
1578 static void remember_in_history(char *str)
1579 {
1580         int i;
1581
1582         if (!(state->flags & DO_HISTORY))
1583                 return;
1584         if (str[0] == '\0')
1585                 return;
1586         i = state->cnt_history;
1587         /* Don't save dupes */
1588         if (i && strcmp(state->history[i-1], str) == 0)
1589                 return;
1590
1591         free(state->history[state->max_history]); /* redundant, paranoia */
1592         state->history[state->max_history] = NULL; /* redundant, paranoia */
1593
1594         /* If history[] is full, remove the oldest command */
1595         /* we need to keep history[state->max_history] empty, hence >=, not > */
1596         if (i >= state->max_history) {
1597                 free(state->history[0]);
1598                 for (i = 0; i < state->max_history-1; i++)
1599                         state->history[i] = state->history[i+1];
1600                 /* i == state->max_history-1 */
1601 # if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1602                 if (state->cnt_history_in_file)
1603                         state->cnt_history_in_file--;
1604 # endif
1605         }
1606         /* i <= state->max_history-1 */
1607         state->history[i++] = xstrdup(str);
1608         /* i <= state->max_history */
1609         state->cur_history = i;
1610         state->cnt_history = i;
1611 # if ENABLE_FEATURE_EDITING_SAVEHISTORY && !ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
1612         save_history(str);
1613 # endif
1614 }
1615
1616 #else /* MAX_HISTORY == 0 */
1617 # define remember_in_history(a) ((void)0)
1618 #endif /* MAX_HISTORY */
1619
1620
1621 #if ENABLE_FEATURE_EDITING_VI
1622 /*
1623  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1624  */
1625 static void
1626 vi_Word_motion(int eat)
1627 {
1628         CHAR_T *command = command_ps;
1629
1630         while (cursor < command_len && !BB_isspace(command[cursor]))
1631                 input_forward();
1632         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1633                 input_forward();
1634 }
1635
1636 static void
1637 vi_word_motion(int eat)
1638 {
1639         CHAR_T *command = command_ps;
1640
1641         if (BB_isalnum_or_underscore(command[cursor])) {
1642                 while (cursor < command_len
1643                  && (BB_isalnum_or_underscore(command[cursor+1]))
1644                 ) {
1645                         input_forward();
1646                 }
1647         } else if (BB_ispunct(command[cursor])) {
1648                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1649                         input_forward();
1650         }
1651
1652         if (cursor < command_len)
1653                 input_forward();
1654
1655         if (eat) {
1656                 while (cursor < command_len && BB_isspace(command[cursor]))
1657                         input_forward();
1658         }
1659 }
1660
1661 static void
1662 vi_End_motion(void)
1663 {
1664         CHAR_T *command = command_ps;
1665
1666         input_forward();
1667         while (cursor < command_len && BB_isspace(command[cursor]))
1668                 input_forward();
1669         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1670                 input_forward();
1671 }
1672
1673 static void
1674 vi_end_motion(void)
1675 {
1676         CHAR_T *command = command_ps;
1677
1678         if (cursor >= command_len-1)
1679                 return;
1680         input_forward();
1681         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1682                 input_forward();
1683         if (cursor >= command_len-1)
1684                 return;
1685         if (BB_isalnum_or_underscore(command[cursor])) {
1686                 while (cursor < command_len-1
1687                  && (BB_isalnum_or_underscore(command[cursor+1]))
1688                 ) {
1689                         input_forward();
1690                 }
1691         } else if (BB_ispunct(command[cursor])) {
1692                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1693                         input_forward();
1694         }
1695 }
1696
1697 static void
1698 vi_Back_motion(void)
1699 {
1700         CHAR_T *command = command_ps;
1701
1702         while (cursor > 0 && BB_isspace(command[cursor-1]))
1703                 input_backward(1);
1704         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1705                 input_backward(1);
1706 }
1707
1708 static void
1709 vi_back_motion(void)
1710 {
1711         CHAR_T *command = command_ps;
1712
1713         if (cursor <= 0)
1714                 return;
1715         input_backward(1);
1716         while (cursor > 0 && BB_isspace(command[cursor]))
1717                 input_backward(1);
1718         if (cursor <= 0)
1719                 return;
1720         if (BB_isalnum_or_underscore(command[cursor])) {
1721                 while (cursor > 0
1722                  && (BB_isalnum_or_underscore(command[cursor-1]))
1723                 ) {
1724                         input_backward(1);
1725                 }
1726         } else if (BB_ispunct(command[cursor])) {
1727                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1728                         input_backward(1);
1729         }
1730 }
1731 #endif
1732
1733 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1734 static void ctrl_left(void)
1735 {
1736         CHAR_T *command = command_ps;
1737
1738         while (1) {
1739                 CHAR_T c;
1740
1741                 input_backward(1);
1742                 if (cursor == 0)
1743                         break;
1744                 c = command[cursor];
1745                 if (c != ' ' && !BB_ispunct(c)) {
1746                         /* we reached a "word" delimited by spaces/punct.
1747                          * go to its beginning */
1748                         while (1) {
1749                                 c = command[cursor - 1];
1750                                 if (c == ' ' || BB_ispunct(c))
1751                                         break;
1752                                 input_backward(1);
1753                                 if (cursor == 0)
1754                                         break;
1755                         }
1756                         break;
1757                 }
1758         }
1759 }
1760 static void ctrl_right(void)
1761 {
1762         CHAR_T *command = command_ps;
1763
1764         while (1) {
1765                 CHAR_T c;
1766
1767                 c = command[cursor];
1768                 if (c == BB_NUL)
1769                         break;
1770                 if (c != ' ' && !BB_ispunct(c)) {
1771                         /* we reached a "word" delimited by spaces/punct.
1772                          * go to its end + 1 */
1773                         while (1) {
1774                                 input_forward();
1775                                 c = command[cursor];
1776                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1777                                         break;
1778                         }
1779                         break;
1780                 }
1781                 input_forward();
1782         }
1783 }
1784
1785
1786 /*
1787  * read_line_input and its helpers
1788  */
1789
1790 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1791 static void ask_terminal(void)
1792 {
1793         /* Ask terminal where is the cursor now.
1794          * lineedit_read_key handles response and corrects
1795          * our idea of current cursor position.
1796          * Testcase: run "echo -n long_line_long_line_long_line",
1797          * then type in a long, wrapping command and try to
1798          * delete it using backspace key.
1799          * Note: we print it _after_ prompt, because
1800          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1801          */
1802         /* Problem: if there is buffered input on stdin,
1803          * the response will be delivered later,
1804          * possibly to an unsuspecting application.
1805          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1806          * Result:
1807          * ~/srcdevel/bbox/fix/busybox.t4 #
1808          * ~/srcdevel/bbox/fix/busybox.t4 #
1809          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1810          * ~/srcdevel/bbox/fix/busybox.t4 #
1811          *
1812          * Checking for input with poll only makes the race narrower,
1813          * I still can trigger it. Strace:
1814          *
1815          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1816          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1817          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1818          * poll([{fd=0, events=POLLIN}], 1, -1) = 1 ([{fd=0, revents=POLLIN}])
1819          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1820          */
1821         struct pollfd pfd;
1822
1823         pfd.fd = STDIN_FILENO;
1824         pfd.events = POLLIN;
1825         if (safe_poll(&pfd, 1, 0) == 0) {
1826                 S.sent_ESC_br6n = 1;
1827                 fputs(ESC"[6n", stdout);
1828                 fflush_all(); /* make terminal see it ASAP! */
1829         }
1830 }
1831 #else
1832 #define ask_terminal() ((void)0)
1833 #endif
1834
1835 /* Note about multi-line PS1 (e.g. "\n\w \u@\h\n> ") and prompt redrawing:
1836  *
1837  * If the prompt has any newlines, after we print it once we use only its last
1838  * line to redraw in-place, which makes it simpler to calculate how many lines
1839  * we should move the cursor up to align the redraw (cmdedit_y). The earlier
1840  * prompt lines just stay on screen and we redraw below them.
1841  *
1842  * Use cases for all prompt lines beyond the initial draw:
1843  * - After clear-screen (^L) or after displaying tab-completion choices, we
1844  *   print the full prompt, as it isn't redrawn in-place.
1845  * - During terminal resize we could try to redraw all lines, but we don't,
1846  *   because it requires delicate alignment, it's good enough with only the
1847  *   last line, and doing it wrong is arguably worse than not doing it at all.
1848  *
1849  * Terminology wise, if it doesn't mention "full", then it means the last/sole
1850  * prompt line. We use the prompt (last/sole line) while redrawing in-place,
1851  * and the full where we need a fresh one unrelated to an earlier position.
1852  *
1853  * If PS1 is not multiline, the last/sole line and the full are the same string.
1854  */
1855
1856 /* Called just once at read_line_input() init time */
1857 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1858 static void parse_and_put_prompt(const char *prmt_ptr)
1859 {
1860         const char *p;
1861         cmdedit_prompt = prompt_last_line = prmt_ptr;
1862         p = strrchr(prmt_ptr, '\n');
1863         if (p)
1864                 prompt_last_line = p + 1;
1865         cmdedit_prmt_len = unicode_strwidth(prompt_last_line);
1866         put_prompt();
1867 }
1868 #else
1869 static void parse_and_put_prompt(const char *prmt_ptr)
1870 {
1871         int prmt_size = 0;
1872         char *prmt_mem_ptr = xzalloc(1);
1873 # if ENABLE_USERNAME_OR_HOMEDIR
1874         char *cwd_buf = NULL;
1875 # endif
1876         char flg_not_length = '[';
1877         char cbuf[2];
1878
1879         /*cmdedit_prmt_len = 0; - already is */
1880
1881         cbuf[1] = '\0'; /* never changes */
1882
1883         while (*prmt_ptr) {
1884                 char timebuf[sizeof("HH:MM:SS")];
1885                 char *free_me = NULL;
1886                 char *pbuf;
1887                 char c;
1888
1889                 pbuf = cbuf;
1890                 c = *prmt_ptr++;
1891                 if (c == '\\') {
1892                         const char *cp;
1893                         int l;
1894 /*
1895  * Supported via bb_process_escape_sequence:
1896  * \a   ASCII bell character (07)
1897  * \e   ASCII escape character (033)
1898  * \n   newline
1899  * \r   carriage return
1900  * \\   backslash
1901  * \nnn char with octal code nnn
1902  * Supported:
1903  * \$   if the effective UID is 0, a #, otherwise a $
1904  * \w   current working directory, with $HOME abbreviated with a tilde
1905  *      Note: we do not support $PROMPT_DIRTRIM=n feature
1906  * \W   basename of the current working directory, with $HOME abbreviated with a tilde
1907  * \h   hostname up to the first '.'
1908  * \H   hostname
1909  * \u   username
1910  * \[   begin a sequence of non-printing characters
1911  * \]   end a sequence of non-printing characters
1912  * \T   current time in 12-hour HH:MM:SS format
1913  * \@   current time in 12-hour am/pm format
1914  * \A   current time in 24-hour HH:MM format
1915  * \t   current time in 24-hour HH:MM:SS format
1916  *      (all of the above work as \A)
1917  * Not supported:
1918  * \!   history number of this command
1919  * \#   command number of this command
1920  * \j   number of jobs currently managed by the shell
1921  * \l   basename of the shell's terminal device name
1922  * \s   name of the shell, the basename of $0 (the portion following the final slash)
1923  * \V   release of bash, version + patch level (e.g., 2.00.0)
1924  * \d   date in "Weekday Month Date" format (e.g., "Tue May 26")
1925  * \D{format}
1926  *      format is passed to strftime(3).
1927  *      An empty format results in a locale-specific time representation.
1928  *      The braces are required.
1929  * Mishandled by bb_process_escape_sequence:
1930  * \v   version of bash (e.g., 2.00)
1931  */
1932                         cp = prmt_ptr;
1933                         c = *cp;
1934                         if (c != 't') /* don't treat \t as tab */
1935                                 c = bb_process_escape_sequence(&prmt_ptr);
1936                         if (prmt_ptr == cp) {
1937                                 if (*cp == '\0')
1938                                         break;
1939                                 c = *prmt_ptr++;
1940
1941                                 switch (c) {
1942 # if ENABLE_USERNAME_OR_HOMEDIR
1943                                 case 'u':
1944                                         pbuf = user_buf ? user_buf : (char*)"";
1945                                         break;
1946 # endif
1947                                 case 'H':
1948                                 case 'h':
1949                                         pbuf = free_me = safe_gethostname();
1950                                         if (c == 'h')
1951                                                 strchrnul(pbuf, '.')[0] = '\0';
1952                                         break;
1953                                 case '$':
1954                                         c = (geteuid() == 0 ? '#' : '$');
1955                                         break;
1956                                 case 'T': /* 12-hour HH:MM:SS format */
1957                                 case '@': /* 12-hour am/pm format */
1958                                 case 'A': /* 24-hour HH:MM format */
1959                                 case 't': /* 24-hour HH:MM:SS format */
1960                                         /* We show all of them as 24-hour HH:MM */
1961                                         strftime_HHMMSS(timebuf, sizeof(timebuf), NULL)[-3] = '\0';
1962                                         pbuf = timebuf;
1963                                         break;
1964 # if ENABLE_USERNAME_OR_HOMEDIR
1965                                 case 'w': /* current dir */
1966                                 case 'W': /* basename of cur dir */
1967                                         if (!cwd_buf) {
1968                                                 cwd_buf = xrealloc_getcwd_or_warn(NULL);
1969                                                 if (!cwd_buf)
1970                                                         cwd_buf = (char *)bb_msg_unknown;
1971                                                 else if (home_pwd_buf[0]) {
1972                                                         char *after_home_user;
1973
1974                                                         /* /home/user[/something] -> ~[/something] */
1975                                                         after_home_user = is_prefixed_with(cwd_buf, home_pwd_buf);
1976                                                         if (after_home_user
1977                                                          && (*after_home_user == '/' || *after_home_user == '\0')
1978                                                         ) {
1979                                                                 cwd_buf[0] = '~';
1980                                                                 overlapping_strcpy(cwd_buf + 1, after_home_user);
1981                                                         }
1982                                                 }
1983                                         }
1984                                         pbuf = cwd_buf;
1985                                         if (c == 'w')
1986                                                 break;
1987                                         cp = strrchr(pbuf, '/');
1988                                         if (cp)
1989                                                 pbuf = (char*)cp + 1;
1990                                         break;
1991 # endif
1992 // bb_process_escape_sequence does this now:
1993 //                              case 'e': case 'E':     /* \e \E = \033 */
1994 //                                      c = '\033';
1995 //                                      break;
1996                                 case 'x': case 'X': {
1997                                         char buf2[4];
1998                                         for (l = 0; l < 3;) {
1999                                                 unsigned h;
2000                                                 buf2[l++] = *prmt_ptr;
2001                                                 buf2[l] = '\0';
2002                                                 h = strtoul(buf2, &pbuf, 16);
2003                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
2004                                                         buf2[--l] = '\0';
2005                                                         break;
2006                                                 }
2007                                                 prmt_ptr++;
2008                                         }
2009                                         c = (char)strtoul(buf2, NULL, 16);
2010                                         if (c == 0)
2011                                                 c = '?';
2012                                         pbuf = cbuf;
2013                                         break;
2014                                 }
2015                                 case '[': case ']':
2016                                         if (c == flg_not_length) {
2017                                                 /* Toggle '['/']' hex 5b/5d */
2018                                                 flg_not_length ^= 6;
2019                                                 continue;
2020                                         }
2021                                         break;
2022                                 } /* switch */
2023                         } /* if */
2024                 } /* if */
2025                 cbuf[0] = c;
2026                 {
2027                         int n = strlen(pbuf);
2028                         prmt_size += n;
2029                         if (c == '\n')
2030                                 cmdedit_prmt_len = 0;
2031                         else if (flg_not_length != ']') {
2032 #if 0 /*ENABLE_UNICODE_SUPPORT*/
2033 /* Won't work, pbuf is one BYTE string here instead of an one Unicode char string. */
2034 /* FIXME */
2035                                 cmdedit_prmt_len += unicode_strwidth(pbuf);
2036 #else
2037                                 cmdedit_prmt_len += n;
2038 #endif
2039                         }
2040                 }
2041                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_size+1), pbuf);
2042                 free(free_me);
2043         } /* while */
2044
2045 # if ENABLE_USERNAME_OR_HOMEDIR
2046         if (cwd_buf != (char *)bb_msg_unknown)
2047                 free(cwd_buf);
2048 # endif
2049         /* see comment (above this function) about multiline prompt redrawing */
2050         cmdedit_prompt = prompt_last_line = prmt_mem_ptr;
2051         prmt_ptr = strrchr(cmdedit_prompt, '\n');
2052         if (prmt_ptr)
2053                 prompt_last_line = prmt_ptr + 1;
2054         put_prompt();
2055 }
2056 #endif
2057
2058 #if ENABLE_FEATURE_EDITING_WINCH
2059 static void cmdedit_setwidth(void)
2060 {
2061         int new_y;
2062
2063         cmdedit_termw = get_terminal_width(STDIN_FILENO);
2064         /* new y for current cursor */
2065         new_y = (cursor + cmdedit_prmt_len) / cmdedit_termw;
2066         /* redraw */
2067         redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
2068 }
2069
2070 static void win_changed(int nsig UNUSED_PARAM)
2071 {
2072         if (S.ok_to_redraw) {
2073                 /* We are in read_key(), safe to redraw immediately */
2074                 int sv_errno = errno;
2075                 cmdedit_setwidth();
2076                 fflush_all();
2077                 errno = sv_errno;
2078         } else {
2079                 /* Signal main loop that redraw is necessary */
2080                 S.SIGWINCH_count++;
2081         }
2082 }
2083 #endif
2084
2085 static int lineedit_read_key(char *read_key_buffer, int timeout)
2086 {
2087         int64_t ic;
2088 #if ENABLE_UNICODE_SUPPORT
2089         char unicode_buf[MB_CUR_MAX + 1];
2090         int unicode_idx = 0;
2091 #endif
2092
2093         fflush_all();
2094         while (1) {
2095                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
2096                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
2097                  * insist on full MB_CUR_MAX buffer to declare input like
2098                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
2099                  *
2100                  * Note: read_key sets errno to 0 on success.
2101                  */
2102                 IF_FEATURE_EDITING_WINCH(S.ok_to_redraw = 1;)
2103                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
2104                 IF_FEATURE_EDITING_WINCH(S.ok_to_redraw = 0;)
2105                 if (errno) {
2106 #if ENABLE_UNICODE_SUPPORT
2107                         if (errno == EAGAIN && unicode_idx != 0)
2108                                 goto pushback;
2109 #endif
2110                         break;
2111                 }
2112
2113 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2114                 if ((int32_t)ic == KEYCODE_CURSOR_POS
2115                  && S.sent_ESC_br6n
2116                 ) {
2117                         S.sent_ESC_br6n = 0;
2118                         if (cursor == 0) { /* otherwise it may be bogus */
2119                                 int col = ((ic >> 32) & 0x7fff) - 1;
2120                                 /*
2121                                  * Is col > cmdedit_prmt_len?
2122                                  * If yes (terminal says cursor is farther to the right
2123                                  * of where we think it should be),
2124                                  * the prompt wasn't printed starting at col 1,
2125                                  * there was additional text before it.
2126                                  */
2127                                 if ((int)(col - cmdedit_prmt_len) > 0) {
2128                                         /* Fix our understanding of current x position */
2129                                         cmdedit_x += (col - cmdedit_prmt_len);
2130                                         while (cmdedit_x >= cmdedit_termw) {
2131                                                 cmdedit_x -= cmdedit_termw;
2132                                                 cmdedit_y++;
2133                                         }
2134                                 }
2135                         }
2136                         continue;
2137                 }
2138 #endif
2139
2140 #if ENABLE_UNICODE_SUPPORT
2141                 if (unicode_status == UNICODE_ON) {
2142                         wchar_t wc;
2143
2144                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
2145                                 break;
2146                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
2147
2148                         unicode_buf[unicode_idx++] = ic;
2149                         unicode_buf[unicode_idx] = '\0';
2150                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
2151                                 /* Not (yet?) a valid unicode char */
2152                                 if (unicode_idx < MB_CUR_MAX) {
2153                                         timeout = 50;
2154                                         continue;
2155                                 }
2156  pushback:
2157                                 /* Invalid sequence. Save all "bad bytes" except first */
2158                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
2159 # if !ENABLE_UNICODE_PRESERVE_BROKEN
2160                                 ic = CONFIG_SUBST_WCHAR;
2161 # else
2162                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
2163 # endif
2164                         } else {
2165                                 /* Valid unicode char, return its code */
2166                                 ic = wc;
2167                         }
2168                 }
2169 #endif
2170                 break;
2171         }
2172
2173         return ic;
2174 }
2175
2176 #if ENABLE_UNICODE_BIDI_SUPPORT
2177 static int isrtl_str(void)
2178 {
2179         int idx = cursor;
2180
2181         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
2182                 idx++;
2183         return unicode_bidi_isrtl(command_ps[idx]);
2184 }
2185 #else
2186 # define isrtl_str() 0
2187 #endif
2188
2189 /* leave out the "vi-mode"-only case labels if vi editing isn't
2190  * configured. */
2191 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
2192
2193 /* convert uppercase ascii to equivalent control char, for readability */
2194 #undef CTRL
2195 #define CTRL(a) ((a) & ~0x40)
2196
2197 enum {
2198         VI_CMDMODE_BIT = 0x40000000,
2199         /* 0x80000000 bit flags KEYCODE_xxx */
2200 };
2201
2202 #if ENABLE_FEATURE_REVERSE_SEARCH
2203 /* Mimic readline Ctrl-R reverse history search.
2204  * When invoked, it shows the following prompt:
2205  * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
2206  * and typing results in search being performed:
2207  * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
2208  * Search is performed by looking at progressively older lines in history.
2209  * Ctrl-R again searches for the next match in history.
2210  * Backspace deletes last matched char.
2211  * Control keys exit search and return to normal editing (at current history line).
2212  */
2213 static int32_t reverse_i_search(int timeout)
2214 {
2215         char match_buf[128]; /* for user input */
2216         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2217         const char *matched_history_line;
2218         const char *saved_prompt;
2219         unsigned saved_prmt_len;
2220         int32_t ic;
2221
2222         matched_history_line = NULL;
2223         read_key_buffer[0] = 0;
2224         match_buf[0] = '\0';
2225
2226         /* Save and replace the prompt */
2227         saved_prompt = prompt_last_line;
2228         saved_prmt_len = cmdedit_prmt_len;
2229         goto set_prompt;
2230
2231         while (1) {
2232                 int h;
2233                 unsigned match_buf_len = strlen(match_buf);
2234
2235 //FIXME: correct timeout? (i.e. count it down?)
2236                 ic = lineedit_read_key(read_key_buffer, timeout);
2237
2238                 switch (ic) {
2239                 case CTRL('R'): /* searching for the next match */
2240                         break;
2241
2242                 case '\b':
2243                 case '\x7f':
2244                         /* Backspace */
2245                         if (unicode_status == UNICODE_ON) {
2246                                 while (match_buf_len != 0) {
2247                                         uint8_t c = match_buf[--match_buf_len];
2248                                         if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
2249                                                 break; /* yes */
2250                                 }
2251                         } else {
2252                                 if (match_buf_len != 0)
2253                                         match_buf_len--;
2254                         }
2255                         match_buf[match_buf_len] = '\0';
2256                         break;
2257
2258                 default:
2259                         if (ic < ' '
2260                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2261                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2262                         ) {
2263                                 goto ret;
2264                         }
2265
2266                         /* Append this char */
2267 #if ENABLE_UNICODE_SUPPORT
2268                         if (unicode_status == UNICODE_ON) {
2269                                 mbstate_t mbstate = { 0 };
2270                                 char buf[MB_CUR_MAX + 1];
2271                                 int len = wcrtomb(buf, ic, &mbstate);
2272                                 if (len > 0) {
2273                                         buf[len] = '\0';
2274                                         if (match_buf_len + len < sizeof(match_buf))
2275                                                 strcpy(match_buf + match_buf_len, buf);
2276                                 }
2277                         } else
2278 #endif
2279                         if (match_buf_len < sizeof(match_buf) - 1) {
2280                                 match_buf[match_buf_len] = ic;
2281                                 match_buf[match_buf_len + 1] = '\0';
2282                         }
2283                         break;
2284                 } /* switch (ic) */
2285
2286                 /* Search in history for match_buf */
2287                 h = state->cur_history;
2288                 if (ic == CTRL('R'))
2289                         h--;
2290                 while (h >= 0) {
2291                         if (state->history[h]) {
2292                                 char *match = strstr(state->history[h], match_buf);
2293                                 if (match) {
2294                                         state->cur_history = h;
2295                                         matched_history_line = state->history[h];
2296                                         command_len = load_string(matched_history_line);
2297                                         cursor = match - matched_history_line;
2298 //FIXME: cursor position for Unicode case
2299
2300                                         free((char*)prompt_last_line);
2301  set_prompt:
2302                                         prompt_last_line = xasprintf("(reverse-i-search)'%s': ", match_buf);
2303                                         cmdedit_prmt_len = unicode_strwidth(prompt_last_line);
2304                                         goto do_redraw;
2305                                 }
2306                         }
2307                         h--;
2308                 }
2309
2310                 /* Not found */
2311                 match_buf[match_buf_len] = '\0';
2312                 beep();
2313                 continue;
2314
2315  do_redraw:
2316                 redraw(cmdedit_y, command_len - cursor);
2317         } /* while (1) */
2318
2319  ret:
2320         if (matched_history_line)
2321                 command_len = load_string(matched_history_line);
2322
2323         free((char*)prompt_last_line);
2324         prompt_last_line = saved_prompt;
2325         cmdedit_prmt_len = saved_prmt_len;
2326         redraw(cmdedit_y, command_len - cursor);
2327
2328         return ic;
2329 }
2330 #endif
2331
2332 #if ENABLE_FEATURE_EDITING_WINCH
2333 static void sigaction2(int sig, struct sigaction *act)
2334 {
2335         // Grr... gcc 8.1.1:
2336         // "passing argument 3 to restrict-qualified parameter aliases with argument 2"
2337         // dance around that...
2338         struct sigaction *oact FIX_ALIASING;
2339         oact = act;
2340         sigaction(sig, act, oact);
2341 }
2342 #endif
2343
2344 /* maxsize must be >= 2.
2345  * Returns:
2346  * -1 on read errors or EOF, or on bare Ctrl-D,
2347  * 0  on ctrl-C (the line entered is still returned in 'command'),
2348  * (in both cases the cursor remains on the input line, '\n' is not printed)
2349  * >0 length of input string, including terminating '\n'
2350  */
2351 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize)
2352 {
2353         int len, n;
2354         int timeout;
2355 #if ENABLE_FEATURE_TAB_COMPLETION
2356         smallint lastWasTab = 0;
2357 #endif
2358         smallint break_out = 0;
2359 #if ENABLE_FEATURE_EDITING_VI
2360         smallint vi_cmdmode = 0;
2361 #endif
2362         struct termios initial_settings;
2363         struct termios new_settings;
2364         char read_key_buffer[KEYCODE_BUFFER_SIZE];
2365
2366         INIT_S();
2367
2368         n = get_termios_and_make_raw(STDIN_FILENO, &new_settings, &initial_settings, 0
2369                 | TERMIOS_CLEAR_ISIG /* turn off INTR (ctrl-C), QUIT, SUSP */
2370         );
2371         if (n != 0 || (initial_settings.c_lflag & (ECHO|ICANON)) == ICANON) {
2372                 /* Happens when e.g. stty -echo was run before.
2373                  * But if ICANON is not set, we don't come here.
2374                  * (example: interactive python ^Z-backgrounded,
2375                  * tty is still in "raw mode").
2376                  */
2377                 parse_and_put_prompt(prompt);
2378                 fflush_all();
2379                 if (fgets(command, maxsize, stdin) == NULL)
2380                         len = -1; /* EOF or error */
2381                 else
2382                         len = strlen(command);
2383                 DEINIT_S();
2384                 return len;
2385         }
2386
2387         init_unicode();
2388
2389 // FIXME: audit & improve this
2390         if (maxsize > MAX_LINELEN)
2391                 maxsize = MAX_LINELEN;
2392         S.maxsize = maxsize;
2393
2394         timeout = -1;
2395         /* Make state->flags == 0 if st is NULL.
2396          * With zeroed flags, no other fields are ever referenced.
2397          */
2398         state = (line_input_t*) &const_int_0;
2399         if (st) {
2400                 state = st;
2401                 timeout = st->timeout;
2402         }
2403 #if MAX_HISTORY > 0
2404         if (state->flags & DO_HISTORY) {
2405 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
2406                 if (state->hist_file)
2407                         if (state->cnt_history == 0)
2408                                 load_history(state);
2409 # endif
2410                 state->cur_history = state->cnt_history;
2411         }
2412 #endif
2413
2414         /* prepare before init handlers */
2415         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
2416         command_len = 0;
2417 #if ENABLE_UNICODE_SUPPORT
2418         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
2419 #else
2420         command_ps = command;
2421         command[0] = '\0';
2422 #endif
2423 #define command command_must_not_be_used
2424
2425         tcsetattr_stdin_TCSANOW(&new_settings);
2426
2427 #if ENABLE_USERNAME_OR_HOMEDIR
2428         {
2429                 struct passwd *entry;
2430
2431                 entry = getpwuid(geteuid());
2432                 if (entry) {
2433                         user_buf = xstrdup(entry->pw_name);
2434                         home_pwd_buf = xstrdup(entry->pw_dir);
2435                 }
2436         }
2437 #endif
2438
2439 #if 0
2440         for (i = 0; i <= state->max_history; i++)
2441                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2442         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2443 #endif
2444
2445         /* Get width (before printing prompt) */
2446         cmdedit_termw = get_terminal_width(STDIN_FILENO);
2447         /* Print out the command prompt, optionally ask where cursor is */
2448         parse_and_put_prompt(prompt);
2449         ask_terminal();
2450
2451 #if ENABLE_FEATURE_EDITING_WINCH
2452         /* Install window resize handler (NB: after *all* init is complete) */
2453         S.SIGWINCH_handler.sa_handler = win_changed;
2454         S.SIGWINCH_handler.sa_flags = SA_RESTART;
2455         sigaction2(SIGWINCH, &S.SIGWINCH_handler);
2456 #endif
2457         read_key_buffer[0] = 0;
2458         while (1) {
2459                 /*
2460                  * The emacs and vi modes share much of the code in the big
2461                  * command loop.  Commands entered when in vi's command mode
2462                  * (aka "escape mode") get an extra bit added to distinguish
2463                  * them - this keeps them from being self-inserted. This
2464                  * clutters the big switch a bit, but keeps all the code
2465                  * in one place.
2466                  */
2467                 int32_t ic, ic_raw;
2468 #if ENABLE_FEATURE_EDITING_WINCH
2469                 unsigned count;
2470
2471                 count = S.SIGWINCH_count;
2472                 if (S.SIGWINCH_saved != count) {
2473                         S.SIGWINCH_saved = count;
2474                         cmdedit_setwidth();
2475                 }
2476 #endif
2477                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2478
2479 #if ENABLE_FEATURE_REVERSE_SEARCH
2480  again:
2481 #endif
2482 #if ENABLE_FEATURE_EDITING_VI
2483                 newdelflag = 1;
2484                 if (vi_cmdmode) {
2485                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2486                          * change ic if it contains one of them: */
2487                         ic |= VI_CMDMODE_BIT;
2488                 }
2489 #endif
2490
2491                 switch (ic) {
2492                 case '\n':
2493                 case '\r':
2494                 vi_case('\n'|VI_CMDMODE_BIT:)
2495                 vi_case('\r'|VI_CMDMODE_BIT:)
2496                         /* Enter */
2497                         goto_new_line();
2498                         break_out = 1;
2499                         break;
2500                 case CTRL('A'):
2501                 vi_case('0'|VI_CMDMODE_BIT:)
2502                         /* Control-a -- Beginning of line */
2503                         input_backward(cursor);
2504                         break;
2505                 case CTRL('B'):
2506                 vi_case('h'|VI_CMDMODE_BIT:)
2507                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2508                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2509                         input_backward(1); /* Move back one character */
2510                         break;
2511                 case CTRL('E'):
2512                 vi_case('$'|VI_CMDMODE_BIT:)
2513                         /* Control-e -- End of line */
2514                         put_till_end_and_adv_cursor();
2515                         break;
2516                 case CTRL('F'):
2517                 vi_case('l'|VI_CMDMODE_BIT:)
2518                 vi_case(' '|VI_CMDMODE_BIT:)
2519                         input_forward(); /* Move forward one character */
2520                         break;
2521                 case '\b':   /* ^H */
2522                 case '\x7f': /* DEL */
2523                         if (!isrtl_str())
2524                                 input_backspace();
2525                         else
2526                                 input_delete(0);
2527                         break;
2528                 case KEYCODE_DELETE:
2529                         if (!isrtl_str())
2530                                 input_delete(0);
2531                         else
2532                                 input_backspace();
2533                         break;
2534 #if ENABLE_FEATURE_TAB_COMPLETION
2535                 case '\t':
2536                         input_tab(&lastWasTab);
2537                         break;
2538 #endif
2539                 case CTRL('K'):
2540                         /* Control-k -- clear to end of line */
2541                         command_ps[cursor] = BB_NUL;
2542                         command_len = cursor;
2543                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2544                         break;
2545                 case CTRL('L'):
2546                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2547                         /* Control-l -- clear screen */
2548                         /* cursor to top,left; clear to the end of screen */
2549                         printf(ESC"[H" ESC"[J");
2550                         draw_full(command_len - cursor);
2551                         break;
2552 #if MAX_HISTORY > 0
2553                 case CTRL('N'):
2554                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2555                 vi_case('j'|VI_CMDMODE_BIT:)
2556                         /* Control-n -- Get next command in history */
2557                         if (get_next_history())
2558                                 goto rewrite_line;
2559                         break;
2560                 case CTRL('P'):
2561                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2562                 vi_case('k'|VI_CMDMODE_BIT:)
2563                         /* Control-p -- Get previous command from history */
2564                         if (get_previous_history())
2565                                 goto rewrite_line;
2566                         break;
2567 #endif
2568                 case CTRL('U'):
2569                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2570                         /* Control-U -- Clear line before cursor */
2571                         if (cursor) {
2572                                 command_len -= cursor;
2573                                 memmove(command_ps, command_ps + cursor,
2574                                         (command_len + 1) * sizeof(command_ps[0]));
2575                                 redraw(cmdedit_y, command_len);
2576                         }
2577                         break;
2578                 case CTRL('W'):
2579                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2580                         /* Control-W -- Remove the last word */
2581                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2582                                 input_backspace();
2583                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2584                                 input_backspace();
2585                         break;
2586                 case KEYCODE_ALT_D: {
2587                         /* Delete word forward */
2588                         int nc, sc = cursor;
2589                         ctrl_right();
2590                         nc = cursor - sc;
2591                         input_backward(nc);
2592                         while (--nc >= 0)
2593                                 input_delete(1);
2594                         break;
2595                 }
2596                 case KEYCODE_ALT_BACKSPACE: {
2597                         /* Delete word backward */
2598                         int sc = cursor;
2599                         ctrl_left();
2600                         while (sc-- > cursor)
2601                                 input_delete(1);
2602                         break;
2603                 }
2604 #if ENABLE_FEATURE_REVERSE_SEARCH
2605                 case CTRL('R'):
2606                         ic = ic_raw = reverse_i_search(timeout);
2607                         goto again;
2608 #endif
2609
2610 #if ENABLE_FEATURE_EDITING_VI
2611                 case 'i'|VI_CMDMODE_BIT:
2612                         vi_cmdmode = 0;
2613                         break;
2614                 case 'I'|VI_CMDMODE_BIT:
2615                         input_backward(cursor);
2616                         vi_cmdmode = 0;
2617                         break;
2618                 case 'a'|VI_CMDMODE_BIT:
2619                         input_forward();
2620                         vi_cmdmode = 0;
2621                         break;
2622                 case 'A'|VI_CMDMODE_BIT:
2623                         put_till_end_and_adv_cursor();
2624                         vi_cmdmode = 0;
2625                         break;
2626                 case 'x'|VI_CMDMODE_BIT:
2627                         input_delete(1);
2628                         break;
2629                 case 'X'|VI_CMDMODE_BIT:
2630                         if (cursor > 0) {
2631                                 input_backward(1);
2632                                 input_delete(1);
2633                         }
2634                         break;
2635                 case 'W'|VI_CMDMODE_BIT:
2636                         vi_Word_motion(1);
2637                         break;
2638                 case 'w'|VI_CMDMODE_BIT:
2639                         vi_word_motion(1);
2640                         break;
2641                 case 'E'|VI_CMDMODE_BIT:
2642                         vi_End_motion();
2643                         break;
2644                 case 'e'|VI_CMDMODE_BIT:
2645                         vi_end_motion();
2646                         break;
2647                 case 'B'|VI_CMDMODE_BIT:
2648                         vi_Back_motion();
2649                         break;
2650                 case 'b'|VI_CMDMODE_BIT:
2651                         vi_back_motion();
2652                         break;
2653                 case 'C'|VI_CMDMODE_BIT:
2654                         vi_cmdmode = 0;
2655                         /* fall through */
2656                 case 'D'|VI_CMDMODE_BIT:
2657                         goto clear_to_eol;
2658
2659                 case 'c'|VI_CMDMODE_BIT:
2660                         vi_cmdmode = 0;
2661                         /* fall through */
2662                 case 'd'|VI_CMDMODE_BIT: {
2663                         int nc, sc;
2664
2665                         ic = lineedit_read_key(read_key_buffer, timeout);
2666                         if (errno) /* error */
2667                                 goto return_error_indicator;
2668                         if (ic == ic_raw) { /* "cc", "dd" */
2669                                 input_backward(cursor);
2670                                 goto clear_to_eol;
2671                                 break;
2672                         }
2673
2674                         sc = cursor;
2675                         switch (ic) {
2676                         case 'w':
2677                         case 'W':
2678                         case 'e':
2679                         case 'E':
2680                                 switch (ic) {
2681                                 case 'w':   /* "dw", "cw" */
2682                                         vi_word_motion(vi_cmdmode);
2683                                         break;
2684                                 case 'W':   /* 'dW', 'cW' */
2685                                         vi_Word_motion(vi_cmdmode);
2686                                         break;
2687                                 case 'e':   /* 'de', 'ce' */
2688                                         vi_end_motion();
2689                                         input_forward();
2690                                         break;
2691                                 case 'E':   /* 'dE', 'cE' */
2692                                         vi_End_motion();
2693                                         input_forward();
2694                                         break;
2695                                 }
2696                                 nc = cursor;
2697                                 input_backward(cursor - sc);
2698                                 while (nc-- > cursor)
2699                                         input_delete(1);
2700                                 break;
2701                         case 'b':  /* "db", "cb" */
2702                         case 'B':  /* implemented as B */
2703                                 if (ic == 'b')
2704                                         vi_back_motion();
2705                                 else
2706                                         vi_Back_motion();
2707                                 while (sc-- > cursor)
2708                                         input_delete(1);
2709                                 break;
2710                         case ' ':  /* "d ", "c " */
2711                                 input_delete(1);
2712                                 break;
2713                         case '$':  /* "d$", "c$" */
2714  clear_to_eol:
2715                                 while (cursor < command_len)
2716                                         input_delete(1);
2717                                 break;
2718                         }
2719                         break;
2720                 }
2721                 case 'p'|VI_CMDMODE_BIT:
2722                         input_forward();
2723                         /* fallthrough */
2724                 case 'P'|VI_CMDMODE_BIT:
2725                         put();
2726                         break;
2727                 case 'r'|VI_CMDMODE_BIT:
2728 //FIXME: unicode case?
2729                         ic = lineedit_read_key(read_key_buffer, timeout);
2730                         if (errno) /* error */
2731                                 goto return_error_indicator;
2732                         if (ic < ' ' || ic > 255) {
2733                                 beep();
2734                         } else {
2735                                 command_ps[cursor] = ic;
2736                                 bb_putchar(ic);
2737                                 bb_putchar('\b');
2738                         }
2739                         break;
2740                 case '\x1b': /* ESC */
2741                         if (state->flags & VI_MODE) {
2742                                 /* insert mode --> command mode */
2743                                 vi_cmdmode = 1;
2744                                 input_backward(1);
2745                         }
2746                         break;
2747 #endif /* FEATURE_COMMAND_EDITING_VI */
2748
2749 #if MAX_HISTORY > 0
2750                 case KEYCODE_UP:
2751                         if (get_previous_history())
2752                                 goto rewrite_line;
2753                         beep();
2754                         break;
2755                 case KEYCODE_DOWN:
2756                         if (!get_next_history())
2757                                 break;
2758  rewrite_line:
2759                         /* Rewrite the line with the selected history item */
2760                         /* change command */
2761                         command_len = load_string(state->history[state->cur_history] ?
2762                                         state->history[state->cur_history] : "");
2763                         /* redraw and go to eol (bol, in vi) */
2764                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2765                         break;
2766 #endif
2767                 case KEYCODE_RIGHT:
2768                         input_forward();
2769                         break;
2770                 case KEYCODE_LEFT:
2771                         input_backward(1);
2772                         break;
2773                 case KEYCODE_CTRL_LEFT:
2774                 case KEYCODE_ALT_LEFT: /* bash doesn't do it */
2775                         ctrl_left();
2776                         break;
2777                 case KEYCODE_CTRL_RIGHT:
2778                 case KEYCODE_ALT_RIGHT: /* bash doesn't do it */
2779                         ctrl_right();
2780                         break;
2781                 case KEYCODE_HOME:
2782                         input_backward(cursor);
2783                         break;
2784                 case KEYCODE_END:
2785                         put_till_end_and_adv_cursor();
2786                         break;
2787
2788                 default:
2789                         if (initial_settings.c_cc[VINTR] != 0
2790                          && ic_raw == initial_settings.c_cc[VINTR]
2791                         ) {
2792                                 /* Ctrl-C (usually) - stop gathering input */
2793                                 command_len = 0;
2794                                 break_out = -1; /* "do not append '\n'" */
2795                                 break;
2796                         }
2797                         if (initial_settings.c_cc[VEOF] != 0
2798                          && ic_raw == initial_settings.c_cc[VEOF]
2799                         ) {
2800                                 /* Ctrl-D (usually) - delete one character,
2801                                  * or exit if len=0 and no chars to delete */
2802                                 if (command_len == 0) {
2803                                         errno = 0;
2804
2805                 case -1: /* error (e.g. EIO when tty is destroyed) */
2806  IF_FEATURE_EDITING_VI(return_error_indicator:)
2807                                         break_out = command_len = -1;
2808                                         break;
2809                                 }
2810                                 input_delete(0);
2811                                 break;
2812                         }
2813 //                      /* Control-V -- force insert of next char */
2814 //                      if (c == CTRL('V')) {
2815 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2816 //                                      goto return_error_indicator;
2817 //                              if (c == 0) {
2818 //                                      beep();
2819 //                                      break;
2820 //                              }
2821 //                      }
2822                         if (ic < ' '
2823                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2824                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2825                         ) {
2826                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2827                                  * and vi mode ignores unexpected chars.
2828                                  * Otherwise, we are here if ic is a
2829                                  * control char or an unhandled ESC sequence,
2830                                  * which is also ignored.
2831                                  */
2832                                 break;
2833                         }
2834                         if ((int)command_len >= (maxsize - 2)) {
2835                                 /* Not enough space for the char and EOL */
2836                                 break;
2837                         }
2838
2839                         command_len++;
2840                         if (cursor == (command_len - 1)) {
2841                                 /* We are at the end, append */
2842                                 command_ps[cursor] = ic;
2843                                 command_ps[cursor + 1] = BB_NUL;
2844                                 put_cur_glyph_and_inc_cursor();
2845                                 if (unicode_bidi_isrtl(ic))
2846                                         input_backward(1);
2847                         } else {
2848                                 /* In the middle, insert */
2849                                 int sc = cursor;
2850
2851                                 memmove(command_ps + sc + 1, command_ps + sc,
2852                                         (command_len - sc) * sizeof(command_ps[0]));
2853                                 command_ps[sc] = ic;
2854                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2855                                 if (!isrtl_str())
2856                                         sc++; /* no */
2857                                 put_till_end_and_adv_cursor();
2858                                 /* to prev x pos + 1 */
2859                                 input_backward(cursor - sc);
2860                         }
2861                         break;
2862                 } /* switch (ic) */
2863
2864                 if (break_out)
2865                         break;
2866
2867 #if ENABLE_FEATURE_TAB_COMPLETION
2868                 if (ic_raw != '\t')
2869                         lastWasTab = 0;
2870 #endif
2871         } /* while (1) */
2872
2873 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2874         if (S.sent_ESC_br6n) {
2875                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2876                  * We sent "ESC [ 6 n", but got '\n' first, and
2877                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2878                  * It's bad already and not much can be done with it
2879                  * (it _will_ be visible for the next process to read stdin),
2880                  * but without this delay it even shows up on the screen
2881                  * as garbage because we restore echo settings with tcsetattr
2882                  * before it comes in. UGLY!
2883                  */
2884                 usleep(20*1000);
2885         }
2886 #endif
2887
2888 /* End of bug-catching "command_must_not_be_used" trick */
2889 #undef command
2890
2891 #if ENABLE_UNICODE_SUPPORT
2892         command[0] = '\0';
2893         if (command_len > 0)
2894                 command_len = save_string(command, maxsize - 1);
2895         free(command_ps);
2896 #endif
2897
2898         if (command_len > 0) {
2899                 remember_in_history(command);
2900         }
2901
2902         if (break_out > 0) {
2903                 command[command_len++] = '\n';
2904                 command[command_len] = '\0';
2905         }
2906
2907 #if ENABLE_FEATURE_TAB_COMPLETION
2908         free_tab_completion_data();
2909 #endif
2910
2911         /* restore initial_settings */
2912         tcsetattr_stdin_TCSANOW(&initial_settings);
2913 #if ENABLE_FEATURE_EDITING_WINCH
2914         /* restore SIGWINCH handler */
2915         sigaction_set(SIGWINCH, &S.SIGWINCH_handler);
2916 #endif
2917         fflush_all();
2918
2919         len = command_len;
2920         DEINIT_S();
2921
2922         return len; /* can't return command_len, DEINIT_S() destroys it */
2923 }
2924
2925 #else  /* !FEATURE_EDITING */
2926
2927 #undef read_line_input
2928 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2929 {
2930         fputs(prompt, stdout);
2931         fflush_all();
2932         if (!fgets(command, maxsize, stdin))
2933                 return -1;
2934         return strlen(command);
2935 }
2936
2937 #endif  /* !FEATURE_EDITING */
2938
2939
2940 /*
2941  * Testing
2942  */
2943
2944 #ifdef TEST
2945
2946 #include <locale.h>
2947
2948 const char *applet_name = "debug stuff usage";
2949
2950 int main(int argc, char **argv)
2951 {
2952         char buff[MAX_LINELEN];
2953         char *prompt =
2954 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2955                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2956                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2957                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[m\\]";
2958 #else
2959                 "% ";
2960 #endif
2961
2962         while (1) {
2963                 int l;
2964                 l = read_line_input(prompt, buff);
2965                 if (l <= 0 || buff[l-1] != '\n')
2966                         break;
2967                 buff[l-1] = '\0';
2968                 printf("*** read_line_input() returned line =%s=\n", buff);
2969         }
2970         printf("*** read_line_input() detect ^D\n");
2971         return 0;
2972 }
2973
2974 #endif  /* TEST */