libbb/lineedit.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Command line editing.
   4  *
   5  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
   6  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Used ideas:
   9  *      Adam Rogoyski    <rogoyski@cs.utexas.edu>
  10  *      Dave Cinege      <dcinege@psychosis.com>
  11  *      Jakub Jelinek (c) 1995
  12  *      Erik Andersen    <andersen@codepoet.org> (Majorly adjusted for busybox)
  13  *
  14  * This code is 'as is' with no warranty.
  15  */
  16
  17 /*
  18  * Usage and known bugs:
  19  * Terminal key codes are not extensive, more needs to be added.
  20  * This version was created on Debian GNU/Linux 2.x.
  21  * Delete, Backspace, Home, End, and the arrow keys were tested
  22  * to work in an Xterm and console. Ctrl-A also works as Home.
  23  * Ctrl-E also works as End.
  24  *
  25  * The following readline-like commands are not implemented:
  26  * ESC-b -- Move back one word
  27  * ESC-f -- Move forward one word
  28  * ESC-d -- Delete forward one word
  29  * CTL-t -- Transpose two characters
  30  *
  31  * lineedit does not know that the terminal escape sequences do not
  32  * take up space on the screen. The redisplay code assumes, unless
  33  * told otherwise, that each character in the prompt is a printable
  34  * character that takes up one character position on the screen.
  35  * You need to tell lineedit that some sequences of characters
  36  * in the prompt take up no screen space. Compatibly with readline,
  37  * use the \[ escape to begin a sequence of non-printing characters,
  38  * and the \] escape to signal the end of such a sequence. Example:
  39  *
  40  * PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w \$\[\033[00m\] '
  41  */
  42 #include "libbb.h"
  43 #include "unicode.h"
  44
  45 #ifdef TEST
  46 # define ENABLE_FEATURE_EDITING 0
  47 # define ENABLE_FEATURE_TAB_COMPLETION 0
  48 # define ENABLE_FEATURE_USERNAME_COMPLETION 0
  49 #endif
  50
  51
  52 /* Entire file (except TESTing part) sits inside this #if */
  53 #if ENABLE_FEATURE_EDITING
  54
  55
  56 #define ENABLE_USERNAME_OR_HOMEDIR \
  57         (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
  58 #define IF_USERNAME_OR_HOMEDIR(...)
  59 #if ENABLE_USERNAME_OR_HOMEDIR
  60 # undef IF_USERNAME_OR_HOMEDIR
  61 # define IF_USERNAME_OR_HOMEDIR(...) __VA_ARGS__
  62 #endif
  63
  64
  65 #undef CHAR_T
  66 #if ENABLE_UNICODE_SUPPORT
  67 # define BB_NUL ((wchar_t)0)
  68 # define CHAR_T wchar_t
  69 static bool BB_isspace(CHAR_T c) { return ((unsigned)c < 256 && isspace(c)); }
  70 # if ENABLE_FEATURE_EDITING_VI
  71 static bool BB_isalnum(CHAR_T c) { return ((unsigned)c < 256 && isalnum(c)); }
  72 # endif
  73 static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
  74 # undef isspace
  75 # undef isalnum
  76 # undef ispunct
  77 # undef isprint
  78 # define isspace isspace_must_not_be_used
  79 # define isalnum isalnum_must_not_be_used
  80 # define ispunct ispunct_must_not_be_used
  81 # define isprint isprint_must_not_be_used
  82 #else
  83 # define BB_NUL '\0'
  84 # define CHAR_T char
  85 # define BB_isspace(c) isspace(c)
  86 # define BB_isalnum(c) isalnum(c)
  87 # define BB_ispunct(c) ispunct(c)
  88 #endif
  89 #if ENABLE_UNICODE_PRESERVE_BROKEN
  90 # define unicode_mark_raw_byte(wc)   ((wc) | 0x20000000)
  91 # define unicode_is_raw_byte(wc)     ((wc) & 0x20000000)
  92 #else
  93 # define unicode_is_raw_byte(wc)     0
  94 #endif
  95
  96
  97 #define ESC "\033"
  98
  99 #define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
 100 //#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 101
 102
 103 enum {
 104         MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
 105                       ? CONFIG_FEATURE_EDITING_MAX_LEN
 106                       : 0x7ff0
 107 };
 108
 109 #if ENABLE_USERNAME_OR_HOMEDIR
 110 static const char null_str[] ALIGN1 = "";
 111 #endif
 112
 113 /* We try to minimize both static and stack usage. */
 114 struct lineedit_statics {
 115         line_input_t *state;
 116
 117         volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
 118         sighandler_t previous_SIGWINCH_handler;
 119
 120         unsigned cmdedit_x;        /* real x (col) terminal position */
 121         unsigned cmdedit_y;        /* pseudoreal y (row) terminal position */
 122         unsigned cmdedit_prmt_len; /* length of prompt (without colors etc) */
 123
 124         unsigned cursor;
 125         int command_len; /* must be signed */
 126         /* signed maxsize: we want x in "if (x > S.maxsize)"
 127          * to _not_ be promoted to unsigned */
 128         int maxsize;
 129         CHAR_T *command_ps;
 130
 131         const char *cmdedit_prompt;
 132 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 133         int num_ok_lines; /* = 1; */
 134 #endif
 135
 136 #if ENABLE_USERNAME_OR_HOMEDIR
 137         char *user_buf;
 138         char *home_pwd_buf; /* = (char*)null_str; */
 139 #endif
 140
 141 #if ENABLE_FEATURE_TAB_COMPLETION
 142         char **matches;
 143         unsigned num_matches;
 144 #endif
 145
 146 #if ENABLE_FEATURE_EDITING_VI
 147 # define DELBUFSIZ 128
 148         CHAR_T *delptr;
 149         smallint newdelflag;     /* whether delbuf should be reused yet */
 150         CHAR_T delbuf[DELBUFSIZ];  /* a place to store deleted characters */
 151 #endif
 152 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
 153         smallint sent_ESC_br6n;
 154 #endif
 155 };
 156
 157 /* See lineedit_ptr_hack.c */
 158 extern struct lineedit_statics *const lineedit_ptr_to_statics;
 159
 160 #define S (*lineedit_ptr_to_statics)
 161 #define state            (S.state           )
 162 #define cmdedit_termw    (S.cmdedit_termw   )
 163 #define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
 164 #define cmdedit_x        (S.cmdedit_x       )
 165 #define cmdedit_y        (S.cmdedit_y       )
 166 #define cmdedit_prmt_len (S.cmdedit_prmt_len)
 167 #define cursor           (S.cursor          )
 168 #define command_len      (S.command_len     )
 169 #define command_ps       (S.command_ps      )
 170 #define cmdedit_prompt   (S.cmdedit_prompt  )
 171 #define num_ok_lines     (S.num_ok_lines    )
 172 #define user_buf         (S.user_buf        )
 173 #define home_pwd_buf     (S.home_pwd_buf    )
 174 #define matches          (S.matches         )
 175 #define num_matches      (S.num_matches     )
 176 #define delptr           (S.delptr          )
 177 #define newdelflag       (S.newdelflag      )
 178 #define delbuf           (S.delbuf          )
 179
 180 #define INIT_S() do { \
 181         (*(struct lineedit_statics**)&lineedit_ptr_to_statics) = xzalloc(sizeof(S)); \
 182         barrier(); \
 183         cmdedit_termw = 80; \
 184         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
 185         IF_USERNAME_OR_HOMEDIR(home_pwd_buf = (char*)null_str;) \
 186 } while (0)
 187 static void deinit_S(void)
 188 {
 189 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
 190         /* This one is allocated only if FANCY_PROMPT is on
 191          * (otherwise it points to verbatim prompt (NOT malloced)) */
 192         free((char*)cmdedit_prompt);
 193 #endif
 194 #if ENABLE_USERNAME_OR_HOMEDIR
 195         free(user_buf);
 196         if (home_pwd_buf != null_str)
 197                 free(home_pwd_buf);
 198 #endif
 199         free(lineedit_ptr_to_statics);
 200 }
 201 #define DEINIT_S() deinit_S()
 202
 203
 204 #if ENABLE_UNICODE_SUPPORT
 205 static size_t load_string(const char *src, int maxsize)
 206 {
 207         if (unicode_status == UNICODE_ON) {
 208                 ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
 209                 if (len < 0)
 210                         len = 0;
 211                 command_ps[len] = BB_NUL;
 212                 return len;
 213         } else {
 214                 unsigned i = 0;
 215                 while ((command_ps[i] = src[i]) != 0)
 216                         i++;
 217                 return i;
 218         }
 219 }
 220 static unsigned save_string(char *dst, unsigned maxsize)
 221 {
 222         if (unicode_status == UNICODE_ON) {
 223 # if !ENABLE_UNICODE_PRESERVE_BROKEN
 224                 ssize_t len = wcstombs(dst, command_ps, maxsize - 1);
 225                 if (len < 0)
 226                         len = 0;
 227                 dst[len] = '\0';
 228                 return len;
 229 # else
 230                 unsigned dstpos = 0;
 231                 unsigned srcpos = 0;
 232
 233                 maxsize--;
 234                 while (dstpos < maxsize) {
 235                         wchar_t wc;
 236                         int n = srcpos;
 237
 238                         /* Convert up to 1st invalid byte (or up to end) */
 239                         while ((wc = command_ps[srcpos]) != BB_NUL
 240                             && !unicode_is_raw_byte(wc)
 241                         ) {
 242                                 srcpos++;
 243                         }
 244                         command_ps[srcpos] = BB_NUL;
 245                         n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
 246                         if (n < 0) /* should not happen */
 247                                 break;
 248                         dstpos += n;
 249                         if (wc == BB_NUL) /* usually is */
 250                                 break;
 251
 252                         /* We do have invalid byte here! */
 253                         command_ps[srcpos] = wc; /* restore it */
 254                         srcpos++;
 255                         if (dstpos == maxsize)
 256                                 break;
 257                         dst[dstpos++] = (char) wc;
 258                 }
 259                 dst[dstpos] = '\0';
 260                 return dstpos;
 261 # endif
 262         } else {
 263                 unsigned i = 0;
 264                 while ((dst[i] = command_ps[i]) != 0)
 265                         i++;
 266                 return i;
 267         }
 268 }
 269 /* I thought just fputwc(c, stdout) would work. But no... */
 270 static void BB_PUTCHAR(wchar_t c)
 271 {
 272         if (unicode_status == UNICODE_ON) {
 273                 char buf[MB_CUR_MAX + 1];
 274                 mbstate_t mbst = { 0 };
 275                 ssize_t len = wcrtomb(buf, c, &mbst);
 276                 if (len > 0) {
 277                         buf[len] = '\0';
 278                         fputs(buf, stdout);
 279                 }
 280         } else {
 281                 /* In this case, c is always one byte */
 282                 putchar(c);
 283         }
 284 }
 285 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 286 static wchar_t adjust_width_and_validate_wc(unsigned *width_adj, wchar_t wc)
 287 # else
 288 static wchar_t adjust_width_and_validate_wc(wchar_t wc)
 289 #  define adjust_width_and_validate_wc(width_adj, wc) \
 290         ((*(width_adj))++, adjust_width_and_validate_wc(wc))
 291 # endif
 292 {
 293         int w = 1;
 294
 295         if (unicode_status == UNICODE_ON) {
 296                 if (wc > CONFIG_LAST_SUPPORTED_WCHAR) {
 297                         /* note: also true for unicode_is_raw_byte(wc) */
 298                         goto subst;
 299                 }
 300                 w = wcwidth(wc);
 301                 if ((ENABLE_UNICODE_COMBINING_WCHARS && w < 0)
 302                  || (!ENABLE_UNICODE_COMBINING_WCHARS && w <= 0)
 303                  || (!ENABLE_UNICODE_WIDE_WCHARS && w > 1)
 304                 ) {
 305  subst:
 306                         w = 1;
 307                         wc = CONFIG_SUBST_WCHAR;
 308                 }
 309         }
 310
 311 # if ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS
 312         *width_adj += w;
 313 #endif
 314         return wc;
 315 }
 316 #else /* !UNICODE */
 317 static size_t load_string(const char *src, int maxsize)
 318 {
 319         safe_strncpy(command_ps, src, maxsize);
 320         return strlen(command_ps);
 321 }
 322 # if ENABLE_FEATURE_TAB_COMPLETION
 323 static void save_string(char *dst, unsigned maxsize)
 324 {
 325         safe_strncpy(dst, command_ps, maxsize);
 326 }
 327 # endif
 328 # define BB_PUTCHAR(c) bb_putchar(c)
 329 /* Should never be called: */
 330 int adjust_width_and_validate_wc(unsigned *width_adj, int wc);
 331 #endif
 332
 333
 334 /* Put 'command_ps[cursor]', cursor++.
 335  * Advance cursor on screen. If we reached right margin, scroll text up
 336  * and remove terminal margin effect by printing 'next_char' */
 337 #define HACK_FOR_WRONG_WIDTH 1
 338 static void put_cur_glyph_and_inc_cursor(void)
 339 {
 340         CHAR_T c = command_ps[cursor];
 341         unsigned width = 0;
 342         int ofs_to_right;
 343
 344         if (c == BB_NUL) {
 345                 /* erase character after end of input string */
 346                 c = ' ';
 347         } else {
 348                 /* advance cursor only if we aren't at the end yet */
 349                 cursor++;
 350                 if (unicode_status == UNICODE_ON) {
 351                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x;)
 352                         c = adjust_width_and_validate_wc(&cmdedit_x, c);
 353                         IF_UNICODE_WIDE_WCHARS(width = cmdedit_x - width;)
 354                 } else {
 355                         cmdedit_x++;
 356                 }
 357         }
 358
 359         ofs_to_right = cmdedit_x - cmdedit_termw;
 360         if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right <= 0) {
 361                 /* c fits on this line */
 362                 BB_PUTCHAR(c);
 363         }
 364
 365         if (ofs_to_right >= 0) {
 366                 /* we go to the next line */
 367 #if HACK_FOR_WRONG_WIDTH
 368                 /* This works better if our idea of term width is wrong
 369                  * and it is actually wider (often happens on serial lines).
 370                  * Printing CR,LF *forces* cursor to next line.
 371                  * OTOH if terminal width is correct AND terminal does NOT
 372                  * have automargin (IOW: it is moving cursor to next line
 373                  * by itself (which is wrong for VT-10x terminals)),
 374                  * this will break things: there will be one extra empty line */
 375                 puts("\r"); /* + implicit '\n' */
 376 #else
 377                 /* VT-10x terminals don't wrap cursor to next line when last char
 378                  * on the line is printed - cursor stays "over" this char.
 379                  * Need to print _next_ char too (first one to appear on next line)
 380                  * to make cursor move down to next line.
 381                  */
 382                 /* Works ok only if cmdedit_termw is correct. */
 383                 c = command_ps[cursor];
 384                 if (c == BB_NUL)
 385                         c = ' ';
 386                 BB_PUTCHAR(c);
 387                 bb_putchar('\b');
 388 #endif
 389                 cmdedit_y++;
 390                 if (!ENABLE_UNICODE_WIDE_WCHARS || ofs_to_right == 0) {
 391                         width = 0;
 392                 } else { /* ofs_to_right > 0 */
 393                         /* wide char c didn't fit on prev line */
 394                         BB_PUTCHAR(c);
 395                 }
 396                 cmdedit_x = width;
 397         }
 398 }
 399
 400 /* Move to end of line (by printing all chars till the end) */
 401 static void put_till_end_and_adv_cursor(void)
 402 {
 403         while (cursor < command_len)
 404                 put_cur_glyph_and_inc_cursor();
 405 }
 406
 407 /* Go to the next line */
 408 static void goto_new_line(void)
 409 {
 410         put_till_end_and_adv_cursor();
 411         if (cmdedit_x != 0)
 412                 bb_putchar('\n');
 413 }
 414
 415 static void beep(void)
 416 {
 417         bb_putchar('\007');
 418 }
 419
 420 static void put_prompt(void)
 421 {
 422         unsigned w;
 423
 424         fputs(cmdedit_prompt, stdout);
 425         fflush_all();
 426         cursor = 0;
 427         w = cmdedit_termw; /* read volatile var once */
 428         cmdedit_y = cmdedit_prmt_len / w; /* new quasireal y */
 429         cmdedit_x = cmdedit_prmt_len % w;
 430 }
 431
 432 /* Move back one character */
 433 /* (optimized for slow terminals) */
 434 static void input_backward(unsigned num)
 435 {
 436         if (num > cursor)
 437                 num = cursor;
 438         if (num == 0)
 439                 return;
 440         cursor -= num;
 441
 442         if ((ENABLE_UNICODE_COMBINING_WCHARS || ENABLE_UNICODE_WIDE_WCHARS)
 443          && unicode_status == UNICODE_ON
 444         ) {
 445                 /* correct NUM to be equal to _screen_ width */
 446                 int n = num;
 447                 num = 0;
 448                 while (--n >= 0)
 449                         adjust_width_and_validate_wc(&num, command_ps[cursor + n]);
 450                 if (num == 0)
 451                         return;
 452         }
 453
 454         if (cmdedit_x >= num) {
 455                 cmdedit_x -= num;
 456                 if (num <= 4) {
 457                         /* This is longer by 5 bytes on x86.
 458                          * Also gets miscompiled for ARM users
 459                          * (busybox.net/bugs/view.php?id=2274).
 460                          * printf(("\b\b\b\b" + 4) - num);
 461                          * return;
 462                          */
 463                         do {
 464                                 bb_putchar('\b');
 465                         } while (--num);
 466                         return;
 467                 }
 468                 printf(ESC"[%uD", num);
 469                 return;
 470         }
 471
 472         /* Need to go one or more lines up */
 473         if (ENABLE_UNICODE_WIDE_WCHARS) {
 474                 /* With wide chars, it is hard to "backtrack"
 475                  * and reliably figure out where to put cursor.
 476                  * Example (<> is a wide char; # is an ordinary char, _ cursor):
 477                  * |prompt: <><> |
 478                  * |<><><><><><> |
 479                  * |_            |
 480                  * and user presses left arrow. num = 1, cmdedit_x = 0,
 481                  * We need to go up one line, and then - how do we know that
 482                  * we need to go *10* positions to the right? Because
 483                  * |prompt: <>#<>|
 484                  * |<><><>#<><><>|
 485                  * |_            |
 486                  * in this situation we need to go *11* positions to the right.
 487                  *
 488                  * A simpler thing to do is to redraw everything from the start
 489                  * up to new cursor position (which is already known):
 490                  */
 491                 unsigned sv_cursor;
 492                 /* go to 1st column; go up to first line */
 493                 printf("\r" ESC"[%uA", cmdedit_y);
 494                 cmdedit_y = 0;
 495                 sv_cursor = cursor;
 496                 put_prompt(); /* sets cursor to 0 */
 497                 while (cursor < sv_cursor)
 498                         put_cur_glyph_and_inc_cursor();
 499         } else {
 500                 int lines_up;
 501                 unsigned width;
 502                 /* num = chars to go back from the beginning of current line: */
 503                 num -= cmdedit_x;
 504                 width = cmdedit_termw; /* read volatile var once */
 505                 /* num=1...w: one line up, w+1...2w: two, etc: */
 506                 lines_up = 1 + (num - 1) / width;
 507                 cmdedit_x = (width * cmdedit_y - num) % width;
 508                 cmdedit_y -= lines_up;
 509                 /* go to 1st column; go up */
 510                 printf("\r" ESC"[%uA", lines_up);
 511                 /* go to correct column.
 512                  * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
 513                  * need to *make sure* we skip it if cmdedit_x == 0 */
 514                 if (cmdedit_x)
 515                         printf(ESC"[%uC", cmdedit_x);
 516         }
 517 }
 518
 519 /* draw prompt, editor line, and clear tail */
 520 static void redraw(int y, int back_cursor)
 521 {
 522         if (y > 0) /* up y lines */
 523                 printf(ESC"[%uA", y);
 524         bb_putchar('\r');
 525         put_prompt();
 526         put_till_end_and_adv_cursor();
 527         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 528         input_backward(back_cursor);
 529 }
 530
 531 /* Delete the char in front of the cursor, optionally saving it
 532  * for later putback */
 533 #if !ENABLE_FEATURE_EDITING_VI
 534 static void input_delete(void)
 535 #define input_delete(save) input_delete()
 536 #else
 537 static void input_delete(int save)
 538 #endif
 539 {
 540         int j = cursor;
 541
 542         if (j == (int)command_len)
 543                 return;
 544
 545 #if ENABLE_FEATURE_EDITING_VI
 546         if (save) {
 547                 if (newdelflag) {
 548                         delptr = delbuf;
 549                         newdelflag = 0;
 550                 }
 551                 if ((delptr - delbuf) < DELBUFSIZ)
 552                         *delptr++ = command_ps[j];
 553         }
 554 #endif
 555
 556         memmove(command_ps + j, command_ps + j + 1,
 557                         /* (command_len + 1 [because of NUL]) - (j + 1)
 558                          * simplified into (command_len - j) */
 559                         (command_len - j) * sizeof(command_ps[0]));
 560         command_len--;
 561         put_till_end_and_adv_cursor();
 562         /* Last char is still visible, erase it (and more) */
 563         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
 564         input_backward(cursor - j);     /* back to old pos cursor */
 565 }
 566
 567 #if ENABLE_FEATURE_EDITING_VI
 568 static void put(void)
 569 {
 570         int ocursor;
 571         int j = delptr - delbuf;
 572
 573         if (j == 0)
 574                 return;
 575         ocursor = cursor;
 576         /* open hole and then fill it */
 577         memmove(command_ps + cursor + j, command_ps + cursor,
 578                         (command_len - cursor + 1) * sizeof(command_ps[0]));
 579         memcpy(command_ps + cursor, delbuf, j * sizeof(command_ps[0]));
 580         command_len += j;
 581         put_till_end_and_adv_cursor();
 582         input_backward(cursor - ocursor - j + 1); /* at end of new text */
 583 }
 584 #endif
 585
 586 /* Delete the char in back of the cursor */
 587 static void input_backspace(void)
 588 {
 589         if (cursor > 0) {
 590                 input_backward(1);
 591                 input_delete(0);
 592         }
 593 }
 594
 595 /* Move forward one character */
 596 static void input_forward(void)
 597 {
 598         if (cursor < command_len)
 599                 put_cur_glyph_and_inc_cursor();
 600 }
 601
 602 #if ENABLE_FEATURE_TAB_COMPLETION
 603
 604 //FIXME:
 605 //needs to be more clever: currently it thinks that "foo\ b<TAB>
 606 //matches the file named "foo bar", which is untrue.
 607 //Also, perhaps "foo b<TAB> needs to complete to "foo bar" <cursor>,
 608 //not "foo bar <cursor>...
 609
 610 static void free_tab_completion_data(void)
 611 {
 612         if (matches) {
 613                 while (num_matches)
 614                         free(matches[--num_matches]);
 615                 free(matches);
 616                 matches = NULL;
 617         }
 618 }
 619
 620 static void add_match(char *matched)
 621 {
 622         matches = xrealloc_vector(matches, 4, num_matches);
 623         matches[num_matches] = matched;
 624         num_matches++;
 625 }
 626
 627 # if ENABLE_FEATURE_USERNAME_COMPLETION
 628 /* Replace "~user/..." with "/homedir/...".
 629  * The parameter is malloced, free it or return it
 630  * unchanged if no user is matched.
 631  */
 632 static char *username_path_completion(char *ud)
 633 {
 634         struct passwd *entry;
 635         char *tilde_name = ud;
 636         char *home = NULL;
 637
 638         ud++; /* skip ~ */
 639         if (*ud == '/') {       /* "~/..." */
 640                 home = home_pwd_buf;
 641         } else {
 642                 /* "~user/..." */
 643                 ud = strchr(ud, '/');
 644                 *ud = '\0';           /* "~user" */
 645                 entry = getpwnam(tilde_name + 1);
 646                 *ud = '/';            /* restore "~user/..." */
 647                 if (entry)
 648                         home = entry->pw_dir;
 649         }
 650         if (home) {
 651                 ud = concat_path_file(home, ud);
 652                 free(tilde_name);
 653                 tilde_name = ud;
 654         }
 655         return tilde_name;
 656 }
 657
 658 /* ~use<tab> - find all users with this prefix.
 659  * Return the length of the prefix used for matching.
 660  */
 661 static NOINLINE unsigned complete_username(const char *ud)
 662 {
 663         /* Using _r function to avoid pulling in static buffers */
 664         char line_buff[256];
 665         struct passwd pwd;
 666         struct passwd *result;
 667         unsigned userlen;
 668
 669         ud++; /* skip ~ */
 670         userlen = strlen(ud);
 671
 672         setpwent();
 673         while (!getpwent_r(&pwd, line_buff, sizeof(line_buff), &result)) {
 674                 /* Null usernames should result in all users as possible completions. */
 675                 if (/*!userlen || */ strncmp(ud, pwd.pw_name, userlen) == 0) {
 676                         add_match(xasprintf("~%s/", pwd.pw_name));
 677                 }
 678         }
 679         endpwent();
 680
 681         return 1 + userlen;
 682 }
 683 # endif  /* FEATURE_USERNAME_COMPLETION */
 684
 685 enum {
 686         FIND_EXE_ONLY = 0,
 687         FIND_DIR_ONLY = 1,
 688         FIND_FILE_ONLY = 2,
 689 };
 690
 691 static int path_parse(char ***p)
 692 {
 693         int npth;
 694         const char *pth;
 695         char *tmp;
 696         char **res;
 697
 698         if (state->flags & WITH_PATH_LOOKUP)
 699                 pth = state->path_lookup;
 700         else
 701                 pth = getenv("PATH");
 702
 703         /* PATH="" or PATH=":"? */
 704         if (!pth || !pth[0] || LONE_CHAR(pth, ':'))
 705                 return 1;
 706
 707         tmp = (char*)pth;
 708         npth = 1; /* path component count */
 709         while (1) {
 710                 tmp = strchr(tmp, ':');
 711                 if (!tmp)
 712                         break;
 713                 tmp++;
 714                 if (*tmp == '\0')
 715                         break;  /* :<empty> */
 716                 npth++;
 717         }
 718
 719         *p = res = xmalloc(npth * sizeof(res[0]));
 720         res[0] = tmp = xstrdup(pth);
 721         npth = 1;
 722         while (1) {
 723                 tmp = strchr(tmp, ':');
 724                 if (!tmp)
 725                         break;
 726                 *tmp++ = '\0'; /* ':' -> '\0' */
 727                 if (*tmp == '\0')
 728                         break; /* :<empty> */
 729                 res[npth++] = tmp;
 730         }
 731         return npth;
 732 }
 733
 734 /* Complete command, directory or file name.
 735  * Return the length of the prefix used for matching.
 736  */
 737 static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
 738 {
 739         char *path1[1];
 740         char **paths = path1;
 741         int npaths;
 742         int i;
 743         unsigned pf_len;
 744         const char *pfind;
 745         char *dirbuf = NULL;
 746
 747         npaths = 1;
 748         path1[0] = (char*)".";
 749
 750         pfind = strrchr(command, '/');
 751         if (!pfind) {
 752                 if (type == FIND_EXE_ONLY)
 753                         npaths = path_parse(&paths);
 754                 pfind = command;
 755         } else {
 756                 /* point to 'l' in "..../last_component" */
 757                 pfind++;
 758                 /* dirbuf = ".../.../.../" */
 759                 dirbuf = xstrndup(command, pfind - command);
 760 # if ENABLE_FEATURE_USERNAME_COMPLETION
 761                 if (dirbuf[0] == '~')   /* ~/... or ~user/... */
 762                         dirbuf = username_path_completion(dirbuf);
 763 # endif
 764                 path1[0] = dirbuf;
 765         }
 766         pf_len = strlen(pfind);
 767
 768         for (i = 0; i < npaths; i++) {
 769                 DIR *dir;
 770                 struct dirent *next;
 771                 struct stat st;
 772                 char *found;
 773
 774                 dir = opendir(paths[i]);
 775                 if (!dir)
 776                         continue; /* don't print an error */
 777
 778                 while ((next = readdir(dir)) != NULL) {
 779                         unsigned len;
 780                         const char *name_found = next->d_name;
 781
 782                         /* .../<tab>: bash 3.2.0 shows dotfiles, but not . and .. */
 783                         if (!pfind[0] && DOT_OR_DOTDOT(name_found))
 784                                 continue;
 785                         /* match? */
 786                         if (strncmp(name_found, pfind, pf_len) != 0)
 787                                 continue; /* no */
 788
 789                         found = concat_path_file(paths[i], name_found);
 790                         /* NB: stat() first so that we see is it a directory;
 791                          * but if that fails, use lstat() so that
 792                          * we still match dangling links */
 793                         if (stat(found, &st) && lstat(found, &st))
 794                                 goto cont; /* hmm, remove in progress? */
 795
 796                         /* Save only name */
 797                         len = strlen(name_found);
 798                         found = xrealloc(found, len + 2); /* +2: for slash and NUL */
 799                         strcpy(found, name_found);
 800
 801                         if (S_ISDIR(st.st_mode)) {
 802                                 /* name is a directory, add slash */
 803                                 found[len] = '/';
 804                                 found[len + 1] = '\0';
 805                         } else {
 806                                 /* skip files if looking for dirs only (example: cd) */
 807                                 if (type == FIND_DIR_ONLY)
 808                                         goto cont;
 809                         }
 810                         /* add it to the list */
 811                         add_match(found);
 812                         continue;
 813  cont:
 814                         free(found);
 815                 }
 816                 closedir(dir);
 817         } /* for every path */
 818
 819         if (paths != path1) {
 820                 free(paths[0]); /* allocated memory is only in first member */
 821                 free(paths);
 822         }
 823         free(dirbuf);
 824
 825         return pf_len;
 826 }
 827
 828 /* build_match_prefix:
 829  * On entry, match_buf contains everything up to cursor at the moment <tab>
 830  * was pressed. This function looks at it, figures out what part of it
 831  * constitutes the command/file/directory prefix to use for completion,
 832  * and rewrites match_buf to contain only that part.
 833  */
 834 #define dbg_bmp 0
 835 /* Helpers: */
 836 /* QUOT is used on elements of int_buf[], which are bytes,
 837  * not Unicode chars. Therefore it works correctly even in Unicode mode.
 838  */
 839 #define QUOT (UCHAR_MAX+1)
 840 static void remove_chunk(int16_t *int_buf, int beg, int end)
 841 {
 842         /* beg must be <= end */
 843         if (beg == end)
 844                 return;
 845
 846         while ((int_buf[beg] = int_buf[end]) != 0)
 847                 beg++, end++;
 848
 849         if (dbg_bmp) {
 850                 int i;
 851                 for (i = 0; int_buf[i]; i++)
 852                         bb_putchar((unsigned char)int_buf[i]);
 853                 bb_putchar('\n');
 854         }
 855 }
 856 /* Caller ensures that match_buf points to a malloced buffer
 857  * big enough to hold strlen(match_buf)*2 + 2
 858  */
 859 static NOINLINE int build_match_prefix(char *match_buf)
 860 {
 861         int i, j;
 862         int command_mode;
 863         int16_t *int_buf = (int16_t*)match_buf;
 864
 865         if (dbg_bmp) printf("\n%s\n", match_buf);
 866
 867         /* Copy in reverse order, since they overlap */
 868         i = strlen(match_buf);
 869         do {
 870                 int_buf[i] = (unsigned char)match_buf[i];
 871                 i--;
 872         } while (i >= 0);
 873
 874         /* Mark every \c as "quoted c" */
 875         for (i = 0; int_buf[i]; i++) {
 876                 if (int_buf[i] == '\\') {
 877                         remove_chunk(int_buf, i, i + 1);
 878                         int_buf[i] |= QUOT;
 879                 }
 880         }
 881         /* Quote-mark "chars" and 'chars', drop delimiters */
 882         {
 883                 int in_quote = 0;
 884                 i = 0;
 885                 while (int_buf[i]) {
 886                         int cur = int_buf[i];
 887                         if (!cur)
 888                                 break;
 889                         if (cur == '\'' || cur == '"') {
 890                                 if (!in_quote || (cur == in_quote)) {
 891                                         in_quote ^= cur;
 892                                         remove_chunk(int_buf, i, i + 1);
 893                                         continue;
 894                                 }
 895                         }
 896                         if (in_quote)
 897                                 int_buf[i] = cur | QUOT;
 898                         i++;
 899                 }
 900         }
 901
 902         /* Remove everything up to command delimiters:
 903          * ';' ';;' '&' '|' '&&' '||',
 904          * but careful with '>&' '<&' '>|'
 905          */
 906         for (i = 0; int_buf[i]; i++) {
 907                 int cur = int_buf[i];
 908                 if (cur == ';' || cur == '&' || cur == '|') {
 909                         int prev = i ? int_buf[i - 1] : 0;
 910                         if (cur == '&' && (prev == '>' || prev == '<')) {
 911                                 continue;
 912                         } else if (cur == '|' && prev == '>') {
 913                                 continue;
 914                         }
 915                         remove_chunk(int_buf, 0, i + 1 + (cur == int_buf[i + 1]));
 916                         i = -1;  /* back to square 1 */
 917                 }
 918         }
 919         /* Remove all `cmd` */
 920         for (i = 0; int_buf[i]; i++) {
 921                 if (int_buf[i] == '`') {
 922                         for (j = i + 1; int_buf[j]; j++) {
 923                                 if (int_buf[j] == '`') {
 924                                         /* `cmd` should count as a word:
 925                                          * `cmd` c<tab> should search for files c*,
 926                                          * not commands c*. Therefore we don't drop
 927                                          * `cmd` entirely, we replace it with single `.
 928                                          */
 929                                         remove_chunk(int_buf, i, j);
 930                                         goto next;
 931                                 }
 932                         }
 933                         /* No closing ` - command mode, remove all up to ` */
 934                         remove_chunk(int_buf, 0, i + 1);
 935                         break;
 936  next: ;
 937                 }
 938         }
 939
 940         /* Remove "cmd (" and "cmd {"
 941          * Example: "if { c<tab>"
 942          * In this example, c should be matched as command pfx.
 943          */
 944         for (i = 0; int_buf[i]; i++) {
 945                 if (int_buf[i] == '(' || int_buf[i] == '{') {
 946                         remove_chunk(int_buf, 0, i + 1);
 947                         i = -1;  /* back to square 1 */
 948                 }
 949         }
 950
 951         /* Remove leading unquoted spaces */
 952         for (i = 0; int_buf[i]; i++)
 953                 if (int_buf[i] != ' ')
 954                         break;
 955         remove_chunk(int_buf, 0, i);
 956
 957         /* Determine completion mode */
 958         command_mode = FIND_EXE_ONLY;
 959         for (i = 0; int_buf[i]; i++) {
 960                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
 961                         if (int_buf[i] == ' '
 962                          && command_mode == FIND_EXE_ONLY
 963                          && (char)int_buf[0] == 'c'
 964                          && (char)int_buf[1] == 'd'
 965                          && i == 2 /* -> int_buf[2] == ' ' */
 966                         ) {
 967                                 command_mode = FIND_DIR_ONLY;
 968                         } else {
 969                                 command_mode = FIND_FILE_ONLY;
 970                                 break;
 971                         }
 972                 }
 973         }
 974         if (dbg_bmp) printf("command_mode(0:exe/1:dir/2:file):%d\n", command_mode);
 975
 976         /* Remove everything except last word */
 977         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
 978                 continue;
 979         for (--i; i >= 0; i--) {
 980                 int cur = int_buf[i];
 981                 if (cur == ' ' || cur == '<' || cur == '>' || cur == '|' || cur == '&') {
 982                         remove_chunk(int_buf, 0, i + 1);
 983                         break;
 984                 }
 985         }
 986
 987         /* Convert back to string of _chars_ */
 988         i = 0;
 989         while ((match_buf[i] = int_buf[i]) != '\0')
 990                 i++;
 991
 992         if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf);
 993
 994         return command_mode;
 995 }
 996
 997 /*
 998  * Display by column (original idea from ls applet,
 999  * very optimized by me [Vladimir] :)
1000  */
1001 static void showfiles(void)
1002 {
1003         int ncols, row;
1004         int column_width = 0;
1005         int nfiles = num_matches;
1006         int nrows = nfiles;
1007         int l;
1008
1009         /* find the longest file name - use that as the column width */
1010         for (row = 0; row < nrows; row++) {
1011                 l = unicode_strwidth(matches[row]);
1012                 if (column_width < l)
1013                         column_width = l;
1014         }
1015         column_width += 2;              /* min space for columns */
1016         ncols = cmdedit_termw / column_width;
1017
1018         if (ncols > 1) {
1019                 nrows /= ncols;
1020                 if (nfiles % ncols)
1021                         nrows++;        /* round up fractionals */
1022         } else {
1023                 ncols = 1;
1024         }
1025         for (row = 0; row < nrows; row++) {
1026                 int n = row;
1027                 int nc;
1028
1029                 for (nc = 1; nc < ncols && n+nrows < nfiles; n += nrows, nc++) {
1030                         printf("%s%-*s", matches[n],
1031                                 (int)(column_width - unicode_strwidth(matches[n])), ""
1032                         );
1033                 }
1034                 if (ENABLE_UNICODE_SUPPORT)
1035                         puts(printable_string(NULL, matches[n]));
1036                 else
1037                         puts(matches[n]);
1038         }
1039 }
1040
1041 static const char *is_special_char(char c)
1042 {
1043         return strchr(" `\"#$%^&*()=+{}[]:;'|\\<>", c);
1044 }
1045
1046 static char *quote_special_chars(char *found)
1047 {
1048         int l = 0;
1049         char *s = xzalloc((strlen(found) + 1) * 2);
1050
1051         while (*found) {
1052                 if (is_special_char(*found))
1053                         s[l++] = '\\';
1054                 s[l++] = *found++;
1055         }
1056         /* s[l] = '\0'; - already is */
1057         return s;
1058 }
1059
1060 /* Do TAB completion */
1061 static NOINLINE void input_tab(smallint *lastWasTab)
1062 {
1063         char *chosen_match;
1064         char *match_buf;
1065         size_t len_found;
1066         /* Length of string used for matching */
1067         unsigned match_pfx_len = match_pfx_len;
1068         int find_type;
1069 # if ENABLE_UNICODE_SUPPORT
1070         /* cursor pos in command converted to multibyte form */
1071         int cursor_mb;
1072 # endif
1073         if (!(state->flags & TAB_COMPLETION))
1074                 return;
1075
1076         if (*lastWasTab) {
1077                 /* The last char was a TAB too.
1078                  * Print a list of all the available choices.
1079                  */
1080                 if (num_matches > 0) {
1081                         /* cursor will be changed by goto_new_line() */
1082                         int sav_cursor = cursor;
1083                         goto_new_line();
1084                         showfiles();
1085                         redraw(0, command_len - sav_cursor);
1086                 }
1087                 return;
1088         }
1089
1090         *lastWasTab = 1;
1091         chosen_match = NULL;
1092
1093         /* Make a local copy of the string up to the position of the cursor.
1094          * build_match_prefix will expand it into int16_t's, need to allocate
1095          * twice as much as the string_len+1.
1096          * (we then also (ab)use this extra space later - see (**))
1097          */
1098         match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t));
1099 # if !ENABLE_UNICODE_SUPPORT
1100         save_string(match_buf, cursor + 1); /* +1 for NUL */
1101 # else
1102         {
1103                 CHAR_T wc = command_ps[cursor];
1104                 command_ps[cursor] = BB_NUL;
1105                 save_string(match_buf, MAX_LINELEN);
1106                 command_ps[cursor] = wc;
1107                 cursor_mb = strlen(match_buf);
1108         }
1109 # endif
1110         find_type = build_match_prefix(match_buf);
1111
1112         /* Free up any memory already allocated */
1113         free_tab_completion_data();
1114
1115 # if ENABLE_FEATURE_USERNAME_COMPLETION
1116         /* If the word starts with ~ and there is no slash in the word,
1117          * then try completing this word as a username. */
1118         if (state->flags & USERNAME_COMPLETION)
1119                 if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL)
1120                         match_pfx_len = complete_username(match_buf);
1121 # endif
1122         /* If complete_username() did not match,
1123          * try to match a command in $PATH, or a directory, or a file */
1124         if (!matches)
1125                 match_pfx_len = complete_cmd_dir_file(match_buf, find_type);
1126
1127         /* Account for backslashes which will be inserted
1128          * by quote_special_chars() later */
1129         {
1130                 const char *e = match_buf + strlen(match_buf);
1131                 const char *s = e - match_pfx_len;
1132                 while (s < e)
1133                         if (is_special_char(*s++))
1134                                 match_pfx_len++;
1135         }
1136
1137         /* Remove duplicates */
1138         if (matches) {
1139                 unsigned i, n = 0;
1140                 qsort_string_vector(matches, num_matches);
1141                 for (i = 0; i < num_matches - 1; ++i) {
1142                         //if (matches[i] && matches[i+1]) { /* paranoia */
1143                                 if (strcmp(matches[i], matches[i+1]) == 0) {
1144                                         free(matches[i]);
1145                                         //matches[i] = NULL; /* paranoia */
1146                                 } else {
1147                                         matches[n++] = matches[i];
1148                                 }
1149                         //}
1150                 }
1151                 matches[n++] = matches[i];
1152                 num_matches = n;
1153         }
1154
1155         /* Did we find exactly one match? */
1156         if (num_matches != 1) { /* no */
1157                 char *cp;
1158                 beep();
1159                 if (!matches)
1160                         goto ret; /* no matches at all */
1161                 /* Find common prefix */
1162                 chosen_match = xstrdup(matches[0]);
1163                 for (cp = chosen_match; *cp; cp++) {
1164                         unsigned n;
1165                         for (n = 1; n < num_matches; n++) {
1166                                 if (matches[n][cp - chosen_match] != *cp) {
1167                                         goto stop;
1168                                 }
1169                         }
1170                 }
1171  stop:
1172                 if (cp == chosen_match) { /* have unique prefix? */
1173                         goto ret; /* no */
1174                 }
1175                 *cp = '\0';
1176                 cp = quote_special_chars(chosen_match);
1177                 free(chosen_match);
1178                 chosen_match = cp;
1179                 len_found = strlen(chosen_match);
1180         } else {                        /* exactly one match */
1181                 /* Next <tab> is not a double-tab */
1182                 *lastWasTab = 0;
1183
1184                 chosen_match = quote_special_chars(matches[0]);
1185                 len_found = strlen(chosen_match);
1186                 if (chosen_match[len_found-1] != '/') {
1187                         chosen_match[len_found] = ' ';
1188                         chosen_match[++len_found] = '\0';
1189                 }
1190         }
1191
1192 # if !ENABLE_UNICODE_SUPPORT
1193         /* Have space to place the match? */
1194         /* The result consists of three parts with these lengths: */
1195         /* cursor + (len_found - match_pfx_len) + (command_len - cursor) */
1196         /* it simplifies into: */
1197         if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) {
1198                 int pos;
1199                 /* save tail */
1200                 strcpy(match_buf, &command_ps[cursor]);
1201                 /* add match and tail */
1202                 sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf);
1203                 command_len = strlen(command_ps);
1204                 /* new pos */
1205                 pos = cursor + len_found - match_pfx_len;
1206                 /* write out the matched command */
1207                 redraw(cmdedit_y, command_len - pos);
1208         }
1209 # else
1210         {
1211                 /* Use 2nd half of match_buf as scratch space - see (**) */
1212                 char *command = match_buf + MAX_LINELEN;
1213                 int len = save_string(command, MAX_LINELEN);
1214                 /* Have space to place the match? */
1215                 /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */
1216                 if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) {
1217                         int pos;
1218                         /* save tail */
1219                         strcpy(match_buf, &command[cursor_mb]);
1220                         /* where do we want to have cursor after all? */
1221                         strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
1222                         len = load_string(command, S.maxsize);
1223                         /* add match and tail */
1224                         sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
1225                         command_len = load_string(command, S.maxsize);
1226                         /* write out the matched command */
1227                         /* paranoia: load_string can return 0 on conv error,
1228                          * prevent passing pos = (0 - 12) to redraw */
1229                         pos = command_len - len;
1230                         redraw(cmdedit_y, pos >= 0 ? pos : 0);
1231                 }
1232         }
1233 # endif
1234  ret:
1235         free(chosen_match);
1236         free(match_buf);
1237 }
1238
1239 #endif  /* FEATURE_TAB_COMPLETION */
1240
1241
1242 line_input_t* FAST_FUNC new_line_input_t(int flags)
1243 {
1244         line_input_t *n = xzalloc(sizeof(*n));
1245         n->flags = flags;
1246         return n;
1247 }
1248
1249
1250 #if MAX_HISTORY > 0
1251
1252 static void save_command_ps_at_cur_history(void)
1253 {
1254         if (command_ps[0] != BB_NUL) {
1255                 int cur = state->cur_history;
1256                 free(state->history[cur]);
1257
1258 # if ENABLE_UNICODE_SUPPORT
1259                 {
1260                         char tbuf[MAX_LINELEN];
1261                         save_string(tbuf, sizeof(tbuf));
1262                         state->history[cur] = xstrdup(tbuf);
1263                 }
1264 # else
1265                 state->history[cur] = xstrdup(command_ps);
1266 # endif
1267         }
1268 }
1269
1270 /* state->flags is already checked to be nonzero */
1271 static int get_previous_history(void)
1272 {
1273         if ((state->flags & DO_HISTORY) && state->cur_history) {
1274                 save_command_ps_at_cur_history();
1275                 state->cur_history--;
1276                 return 1;
1277         }
1278         beep();
1279         return 0;
1280 }
1281
1282 static int get_next_history(void)
1283 {
1284         if (state->flags & DO_HISTORY) {
1285                 if (state->cur_history < state->cnt_history) {
1286                         save_command_ps_at_cur_history(); /* save the current history line */
1287                         return ++state->cur_history;
1288                 }
1289         }
1290         beep();
1291         return 0;
1292 }
1293
1294 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1295 /* We try to ensure that concurrent additions to the history
1296  * do not overwrite each other.
1297  * Otherwise shell users get unhappy.
1298  *
1299  * History file is trimmed lazily, when it grows several times longer
1300  * than configured MAX_HISTORY lines.
1301  */
1302
1303 static void free_line_input_t(line_input_t *n)
1304 {
1305         int i = n->cnt_history;
1306         while (i > 0)
1307                 free(n->history[--i]);
1308         free(n);
1309 }
1310
1311 /* state->flags is already checked to be nonzero */
1312 static void load_history(line_input_t *st_parm)
1313 {
1314         char *temp_h[MAX_HISTORY];
1315         char *line;
1316         FILE *fp;
1317         unsigned idx, i, line_len;
1318
1319         /* NB: do not trash old history if file can't be opened */
1320
1321         fp = fopen_for_read(st_parm->hist_file);
1322         if (fp) {
1323                 /* clean up old history */
1324                 for (idx = st_parm->cnt_history; idx > 0;) {
1325                         idx--;
1326                         free(st_parm->history[idx]);
1327                         st_parm->history[idx] = NULL;
1328                 }
1329
1330                 /* fill temp_h[], retaining only last MAX_HISTORY lines */
1331                 memset(temp_h, 0, sizeof(temp_h));
1332                 st_parm->cnt_history_in_file = idx = 0;
1333                 while ((line = xmalloc_fgetline(fp)) != NULL) {
1334                         if (line[0] == '\0') {
1335                                 free(line);
1336                                 continue;
1337                         }
1338                         free(temp_h[idx]);
1339                         temp_h[idx] = line;
1340                         st_parm->cnt_history_in_file++;
1341                         idx++;
1342                         if (idx == MAX_HISTORY)
1343                                 idx = 0;
1344                 }
1345                 fclose(fp);
1346
1347                 /* find first non-NULL temp_h[], if any */
1348                 if (st_parm->cnt_history_in_file) {
1349                         while (temp_h[idx] == NULL) {
1350                                 idx++;
1351                                 if (idx == MAX_HISTORY)
1352                                         idx = 0;
1353                         }
1354                 }
1355
1356                 /* copy temp_h[] to st_parm->history[] */
1357                 for (i = 0; i < MAX_HISTORY;) {
1358                         line = temp_h[idx];
1359                         if (!line)
1360                                 break;
1361                         idx++;
1362                         if (idx == MAX_HISTORY)
1363                                 idx = 0;
1364                         line_len = strlen(line);
1365                         if (line_len >= MAX_LINELEN)
1366                                 line[MAX_LINELEN-1] = '\0';
1367                         st_parm->history[i++] = line;
1368                 }
1369                 st_parm->cnt_history = i;
1370         }
1371 }
1372
1373 /* state->flags is already checked to be nonzero */
1374 static void save_history(char *str)
1375 {
1376         int fd;
1377         int len, len2;
1378
1379         fd = open(state->hist_file, O_WRONLY | O_CREAT | O_APPEND, 0600);
1380         if (fd < 0)
1381                 return;
1382         xlseek(fd, 0, SEEK_END); /* paranoia */
1383         len = strlen(str);
1384         str[len] = '\n'; /* we (try to) do atomic write */
1385         len2 = full_write(fd, str, len + 1);
1386         str[len] = '\0';
1387         close(fd);
1388         if (len2 != len + 1)
1389                 return; /* "wtf?" */
1390
1391         /* did we write so much that history file needs trimming? */
1392         state->cnt_history_in_file++;
1393         if (state->cnt_history_in_file > MAX_HISTORY * 4) {
1394                 char *new_name;
1395                 line_input_t *st_temp;
1396
1397                 /* we may have concurrently written entries from others.
1398                  * load them */
1399                 st_temp = new_line_input_t(state->flags);
1400                 st_temp->hist_file = state->hist_file;
1401                 load_history(st_temp);
1402
1403                 /* write out temp file and replace hist_file atomically */
1404                 new_name = xasprintf("%s.%u.new", state->hist_file, (int) getpid());
1405                 fd = open(state->hist_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);
1406                 if (fd >= 0) {
1407                         FILE *fp;
1408                         int i;
1409
1410                         fp = xfdopen_for_write(fd);
1411                         for (i = 0; i < st_temp->cnt_history; i++)
1412                                 fprintf(fp, "%s\n", st_temp->history[i]);
1413                         fclose(fp);
1414                         if (rename(new_name, state->hist_file) == 0)
1415                                 state->cnt_history_in_file = st_temp->cnt_history;
1416                 }
1417                 free(new_name);
1418                 free_line_input_t(st_temp);
1419         }
1420 }
1421 # else
1422 #  define load_history(a) ((void)0)
1423 #  define save_history(a) ((void)0)
1424 # endif /* FEATURE_COMMAND_SAVEHISTORY */
1425
1426 static void remember_in_history(char *str)
1427 {
1428         int i;
1429
1430         if (!(state->flags & DO_HISTORY))
1431                 return;
1432         if (str[0] == '\0')
1433                 return;
1434         i = state->cnt_history;
1435         /* Don't save dupes */
1436         if (i && strcmp(state->history[i-1], str) == 0)
1437                 return;
1438
1439         free(state->history[MAX_HISTORY]); /* redundant, paranoia */
1440         state->history[MAX_HISTORY] = NULL; /* redundant, paranoia */
1441
1442         /* If history[] is full, remove the oldest command */
1443         /* we need to keep history[MAX_HISTORY] empty, hence >=, not > */
1444         if (i >= MAX_HISTORY) {
1445                 free(state->history[0]);
1446                 for (i = 0; i < MAX_HISTORY-1; i++)
1447                         state->history[i] = state->history[i+1];
1448                 /* i == MAX_HISTORY-1 */
1449         }
1450         /* i <= MAX_HISTORY-1 */
1451         state->history[i++] = xstrdup(str);
1452         /* i <= MAX_HISTORY */
1453         state->cur_history = i;
1454         state->cnt_history = i;
1455 # if MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
1456         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1457                 save_history(str);
1458 # endif
1459         IF_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines++;)
1460 }
1461
1462 #else /* MAX_HISTORY == 0 */
1463 # define remember_in_history(a) ((void)0)
1464 #endif /* MAX_HISTORY */
1465
1466
1467 #if ENABLE_FEATURE_EDITING_VI
1468 /*
1469  * vi mode implemented 2005 by Paul Fox <pgf@foxharp.boston.ma.us>
1470  */
1471 static void
1472 vi_Word_motion(int eat)
1473 {
1474         CHAR_T *command = command_ps;
1475
1476         while (cursor < command_len && !BB_isspace(command[cursor]))
1477                 input_forward();
1478         if (eat) while (cursor < command_len && BB_isspace(command[cursor]))
1479                 input_forward();
1480 }
1481
1482 static void
1483 vi_word_motion(int eat)
1484 {
1485         CHAR_T *command = command_ps;
1486
1487         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1488                 while (cursor < command_len
1489                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1490                 ) {
1491                         input_forward();
1492                 }
1493         } else if (BB_ispunct(command[cursor])) {
1494                 while (cursor < command_len && BB_ispunct(command[cursor+1]))
1495                         input_forward();
1496         }
1497
1498         if (cursor < command_len)
1499                 input_forward();
1500
1501         if (eat) {
1502                 while (cursor < command_len && BB_isspace(command[cursor]))
1503                         input_forward();
1504         }
1505 }
1506
1507 static void
1508 vi_End_motion(void)
1509 {
1510         CHAR_T *command = command_ps;
1511
1512         input_forward();
1513         while (cursor < command_len && BB_isspace(command[cursor]))
1514                 input_forward();
1515         while (cursor < command_len-1 && !BB_isspace(command[cursor+1]))
1516                 input_forward();
1517 }
1518
1519 static void
1520 vi_end_motion(void)
1521 {
1522         CHAR_T *command = command_ps;
1523
1524         if (cursor >= command_len-1)
1525                 return;
1526         input_forward();
1527         while (cursor < command_len-1 && BB_isspace(command[cursor]))
1528                 input_forward();
1529         if (cursor >= command_len-1)
1530                 return;
1531         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1532                 while (cursor < command_len-1
1533                  && (BB_isalnum(command[cursor+1]) || command[cursor+1] == '_')
1534                 ) {
1535                         input_forward();
1536                 }
1537         } else if (BB_ispunct(command[cursor])) {
1538                 while (cursor < command_len-1 && BB_ispunct(command[cursor+1]))
1539                         input_forward();
1540         }
1541 }
1542
1543 static void
1544 vi_Back_motion(void)
1545 {
1546         CHAR_T *command = command_ps;
1547
1548         while (cursor > 0 && BB_isspace(command[cursor-1]))
1549                 input_backward(1);
1550         while (cursor > 0 && !BB_isspace(command[cursor-1]))
1551                 input_backward(1);
1552 }
1553
1554 static void
1555 vi_back_motion(void)
1556 {
1557         CHAR_T *command = command_ps;
1558
1559         if (cursor <= 0)
1560                 return;
1561         input_backward(1);
1562         while (cursor > 0 && BB_isspace(command[cursor]))
1563                 input_backward(1);
1564         if (cursor <= 0)
1565                 return;
1566         if (BB_isalnum(command[cursor]) || command[cursor] == '_') {
1567                 while (cursor > 0
1568                  && (BB_isalnum(command[cursor-1]) || command[cursor-1] == '_')
1569                 ) {
1570                         input_backward(1);
1571                 }
1572         } else if (BB_ispunct(command[cursor])) {
1573                 while (cursor > 0 && BB_ispunct(command[cursor-1]))
1574                         input_backward(1);
1575         }
1576 }
1577 #endif
1578
1579 /* Modelled after bash 4.0 behavior of Ctrl-<arrow> */
1580 static void ctrl_left(void)
1581 {
1582         CHAR_T *command = command_ps;
1583
1584         while (1) {
1585                 CHAR_T c;
1586
1587                 input_backward(1);
1588                 if (cursor == 0)
1589                         break;
1590                 c = command[cursor];
1591                 if (c != ' ' && !BB_ispunct(c)) {
1592                         /* we reached a "word" delimited by spaces/punct.
1593                          * go to its beginning */
1594                         while (1) {
1595                                 c = command[cursor - 1];
1596                                 if (c == ' ' || BB_ispunct(c))
1597                                         break;
1598                                 input_backward(1);
1599                                 if (cursor == 0)
1600                                         break;
1601                         }
1602                         break;
1603                 }
1604         }
1605 }
1606 static void ctrl_right(void)
1607 {
1608         CHAR_T *command = command_ps;
1609
1610         while (1) {
1611                 CHAR_T c;
1612
1613                 c = command[cursor];
1614                 if (c == BB_NUL)
1615                         break;
1616                 if (c != ' ' && !BB_ispunct(c)) {
1617                         /* we reached a "word" delimited by spaces/punct.
1618                          * go to its end + 1 */
1619                         while (1) {
1620                                 input_forward();
1621                                 c = command[cursor];
1622                                 if (c == BB_NUL || c == ' ' || BB_ispunct(c))
1623                                         break;
1624                         }
1625                         break;
1626                 }
1627                 input_forward();
1628         }
1629 }
1630
1631
1632 /*
1633  * read_line_input and its helpers
1634  */
1635
1636 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1637 static void ask_terminal(void)
1638 {
1639         /* Ask terminal where is the cursor now.
1640          * lineedit_read_key handles response and corrects
1641          * our idea of current cursor position.
1642          * Testcase: run "echo -n long_line_long_line_long_line",
1643          * then type in a long, wrapping command and try to
1644          * delete it using backspace key.
1645          * Note: we print it _after_ prompt, because
1646          * prompt may contain CR. Example: PS1='\[\r\n\]\w '
1647          */
1648         /* Problem: if there is buffered input on stdin,
1649          * the response will be delivered later,
1650          * possibly to an unsuspecting application.
1651          * Testcase: "sleep 1; busybox ash" + press and hold [Enter].
1652          * Result:
1653          * ~/srcdevel/bbox/fix/busybox.t4 #
1654          * ~/srcdevel/bbox/fix/busybox.t4 #
1655          * ^[[59;34~/srcdevel/bbox/fix/busybox.t4 #  <-- garbage
1656          * ~/srcdevel/bbox/fix/busybox.t4 #
1657          *
1658          * Checking for input with poll only makes the race narrower,
1659          * I still can trigger it. Strace:
1660          *
1661          * write(1, "~/srcdevel/bbox/fix/busybox.t4 # ", 33) = 33
1662          * poll([{fd=0, events=POLLIN}], 1, 0) = 0 (Timeout)  <-- no input exists
1663          * write(1, "\33[6n", 4) = 4  <-- send the ESC sequence, quick!
1664          * poll([{fd=0, events=POLLIN}], 1, 4294967295) = 1 ([{fd=0, revents=POLLIN}])
1665          * read(0, "\n", 1)      = 1  <-- oh crap, user's input got in first
1666          */
1667         struct pollfd pfd;
1668
1669         pfd.fd = STDIN_FILENO;
1670         pfd.events = POLLIN;
1671         if (safe_poll(&pfd, 1, 0) == 0) {
1672                 S.sent_ESC_br6n = 1;
1673                 fputs(ESC"[6n", stdout);
1674                 fflush_all(); /* make terminal see it ASAP! */
1675         }
1676 }
1677 #else
1678 #define ask_terminal() ((void)0)
1679 #endif
1680
1681 #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
1682 static void parse_and_put_prompt(const char *prmt_ptr)
1683 {
1684         cmdedit_prompt = prmt_ptr;
1685         cmdedit_prmt_len = strlen(prmt_ptr);
1686         put_prompt();
1687 }
1688 #else
1689 static void parse_and_put_prompt(const char *prmt_ptr)
1690 {
1691         int prmt_len = 0;
1692         size_t cur_prmt_len = 0;
1693         char flg_not_length = '[';
1694         char *prmt_mem_ptr = xzalloc(1);
1695         char *cwd_buf = xrealloc_getcwd_or_warn(NULL);
1696         char cbuf[2];
1697         char c;
1698         char *pbuf;
1699
1700         cmdedit_prmt_len = 0;
1701
1702         if (!cwd_buf) {
1703                 cwd_buf = (char *)bb_msg_unknown;
1704         }
1705
1706         cbuf[1] = '\0'; /* never changes */
1707
1708         while (*prmt_ptr) {
1709                 char *free_me = NULL;
1710
1711                 pbuf = cbuf;
1712                 c = *prmt_ptr++;
1713                 if (c == '\\') {
1714                         const char *cp = prmt_ptr;
1715                         int l;
1716
1717                         c = bb_process_escape_sequence(&prmt_ptr);
1718                         if (prmt_ptr == cp) {
1719                                 if (*cp == '\0')
1720                                         break;
1721                                 c = *prmt_ptr++;
1722
1723                                 switch (c) {
1724 # if ENABLE_USERNAME_OR_HOMEDIR
1725                                 case 'u':
1726                                         pbuf = user_buf ? user_buf : (char*)"";
1727                                         break;
1728 # endif
1729                                 case 'h':
1730                                         pbuf = free_me = safe_gethostname();
1731                                         *strchrnul(pbuf, '.') = '\0';
1732                                         break;
1733                                 case '$':
1734                                         c = (geteuid() == 0 ? '#' : '$');
1735                                         break;
1736 # if ENABLE_USERNAME_OR_HOMEDIR
1737                                 case 'w':
1738                                         /* /home/user[/something] -> ~[/something] */
1739                                         pbuf = cwd_buf;
1740                                         l = strlen(home_pwd_buf);
1741                                         if (l != 0
1742                                          && strncmp(home_pwd_buf, cwd_buf, l) == 0
1743                                          && (cwd_buf[l]=='/' || cwd_buf[l]=='\0')
1744                                          && strlen(cwd_buf + l) < PATH_MAX
1745                                         ) {
1746                                                 pbuf = free_me = xasprintf("~%s", cwd_buf + l);
1747                                         }
1748                                         break;
1749 # endif
1750                                 case 'W':
1751                                         pbuf = cwd_buf;
1752                                         cp = strrchr(pbuf, '/');
1753                                         if (cp != NULL && cp != pbuf)
1754                                                 pbuf += (cp-pbuf) + 1;
1755                                         break;
1756                                 case '!':
1757                                         pbuf = free_me = xasprintf("%d", num_ok_lines);
1758                                         break;
1759                                 case 'e': case 'E':     /* \e \E = \033 */
1760                                         c = '\033';
1761                                         break;
1762                                 case 'x': case 'X': {
1763                                         char buf2[4];
1764                                         for (l = 0; l < 3;) {
1765                                                 unsigned h;
1766                                                 buf2[l++] = *prmt_ptr;
1767                                                 buf2[l] = '\0';
1768                                                 h = strtoul(buf2, &pbuf, 16);
1769                                                 if (h > UCHAR_MAX || (pbuf - buf2) < l) {
1770                                                         buf2[--l] = '\0';
1771                                                         break;
1772                                                 }
1773                                                 prmt_ptr++;
1774                                         }
1775                                         c = (char)strtoul(buf2, NULL, 16);
1776                                         if (c == 0)
1777                                                 c = '?';
1778                                         pbuf = cbuf;
1779                                         break;
1780                                 }
1781                                 case '[': case ']':
1782                                         if (c == flg_not_length) {
1783                                                 flg_not_length = (flg_not_length == '[' ? ']' : '[');
1784                                                 continue;
1785                                         }
1786                                         break;
1787                                 } /* switch */
1788                         } /* if */
1789                 } /* if */
1790                 cbuf[0] = c;
1791                 cur_prmt_len = strlen(pbuf);
1792                 prmt_len += cur_prmt_len;
1793                 if (flg_not_length != ']')
1794                         cmdedit_prmt_len += cur_prmt_len;
1795                 prmt_mem_ptr = strcat(xrealloc(prmt_mem_ptr, prmt_len+1), pbuf);
1796                 free(free_me);
1797         } /* while */
1798
1799         if (cwd_buf != (char *)bb_msg_unknown)
1800                 free(cwd_buf);
1801         cmdedit_prompt = prmt_mem_ptr;
1802         put_prompt();
1803 }
1804 #endif
1805
1806 static void cmdedit_setwidth(unsigned w, int redraw_flg)
1807 {
1808         cmdedit_termw = w;
1809         if (redraw_flg) {
1810                 /* new y for current cursor */
1811                 int new_y = (cursor + cmdedit_prmt_len) / w;
1812                 /* redraw */
1813                 redraw((new_y >= cmdedit_y ? new_y : cmdedit_y), command_len - cursor);
1814                 fflush_all();
1815         }
1816 }
1817
1818 static void win_changed(int nsig)
1819 {
1820         int sv_errno = errno;
1821         unsigned width;
1822         get_terminal_width_height(0, &width, NULL);
1823         cmdedit_setwidth(width, nsig /* - just a yes/no flag */);
1824         if (nsig == SIGWINCH)
1825                 signal(SIGWINCH, win_changed); /* rearm ourself */
1826         errno = sv_errno;
1827 }
1828
1829 static int lineedit_read_key(char *read_key_buffer, int timeout)
1830 {
1831         int64_t ic;
1832 #if ENABLE_UNICODE_SUPPORT
1833         char unicode_buf[MB_CUR_MAX + 1];
1834         int unicode_idx = 0;
1835 #endif
1836
1837         while (1) {
1838                 /* Wait for input. TIMEOUT = -1 makes read_key wait even
1839                  * on nonblocking stdin, TIMEOUT = 50 makes sure we won't
1840                  * insist on full MB_CUR_MAX buffer to declare input like
1841                  * "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
1842                  *
1843                  * Note: read_key sets errno to 0 on success.
1844                  */
1845                 ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
1846                 if (errno) {
1847 #if ENABLE_UNICODE_SUPPORT
1848                         if (errno == EAGAIN && unicode_idx != 0)
1849                                 goto pushback;
1850 #endif
1851                         break;
1852                 }
1853
1854 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
1855                 if ((int32_t)ic == KEYCODE_CURSOR_POS
1856                  && S.sent_ESC_br6n
1857                 ) {
1858                         S.sent_ESC_br6n = 0;
1859                         if (cursor == 0) { /* otherwise it may be bogus */
1860                                 int col = ((ic >> 32) & 0x7fff) - 1;
1861                                 if (col > cmdedit_prmt_len) {
1862                                         cmdedit_x += (col - cmdedit_prmt_len);
1863                                         while (cmdedit_x >= cmdedit_termw) {
1864                                                 cmdedit_x -= cmdedit_termw;
1865                                                 cmdedit_y++;
1866                                         }
1867                                 }
1868                         }
1869                         continue;
1870                 }
1871 #endif
1872
1873 #if ENABLE_UNICODE_SUPPORT
1874                 if (unicode_status == UNICODE_ON) {
1875                         wchar_t wc;
1876
1877                         if ((int32_t)ic < 0) /* KEYCODE_xxx */
1878                                 break;
1879                         // TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
1880
1881                         unicode_buf[unicode_idx++] = ic;
1882                         unicode_buf[unicode_idx] = '\0';
1883                         if (mbstowcs(&wc, unicode_buf, 1) != 1) {
1884                                 /* Not (yet?) a valid unicode char */
1885                                 if (unicode_idx < MB_CUR_MAX) {
1886                                         timeout = 50;
1887                                         continue;
1888                                 }
1889  pushback:
1890                                 /* Invalid sequence. Save all "bad bytes" except first */
1891                                 read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
1892 # if !ENABLE_UNICODE_PRESERVE_BROKEN
1893                                 ic = CONFIG_SUBST_WCHAR;
1894 # else
1895                                 ic = unicode_mark_raw_byte(unicode_buf[0]);
1896 # endif
1897                         } else {
1898                                 /* Valid unicode char, return its code */
1899                                 ic = wc;
1900                         }
1901                 }
1902 #endif
1903                 break;
1904         }
1905
1906         return ic;
1907 }
1908
1909 #if ENABLE_UNICODE_BIDI_SUPPORT
1910 static int isrtl_str(void)
1911 {
1912         int idx = cursor;
1913
1914         while (idx < command_len && unicode_bidi_is_neutral_wchar(command_ps[idx]))
1915                 idx++;
1916         return unicode_bidi_isrtl(command_ps[idx]);
1917 }
1918 #else
1919 # define isrtl_str() 0
1920 #endif
1921
1922 /* leave out the "vi-mode"-only case labels if vi editing isn't
1923  * configured. */
1924 #define vi_case(caselabel) IF_FEATURE_EDITING_VI(case caselabel)
1925
1926 /* convert uppercase ascii to equivalent control char, for readability */
1927 #undef CTRL
1928 #define CTRL(a) ((a) & ~0x40)
1929
1930 /* maxsize must be >= 2.
1931  * Returns:
1932  * -1 on read errors or EOF, or on bare Ctrl-D,
1933  * 0  on ctrl-C (the line entered is still returned in 'command'),
1934  * >0 length of input string, including terminating '\n'
1935  */
1936 int FAST_FUNC read_line_input(line_input_t *st, const char *prompt, char *command, int maxsize, int timeout)
1937 {
1938         int len;
1939 #if ENABLE_FEATURE_TAB_COMPLETION
1940         smallint lastWasTab = 0;
1941 #endif
1942         smallint break_out = 0;
1943 #if ENABLE_FEATURE_EDITING_VI
1944         smallint vi_cmdmode = 0;
1945 #endif
1946         struct termios initial_settings;
1947         struct termios new_settings;
1948         char read_key_buffer[KEYCODE_BUFFER_SIZE];
1949
1950         INIT_S();
1951
1952         if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
1953          || !(initial_settings.c_lflag & ECHO)
1954         ) {
1955                 /* Happens when e.g. stty -echo was run before */
1956                 parse_and_put_prompt(prompt);
1957                 /* fflush_all(); - done by parse_and_put_prompt */
1958                 if (fgets(command, maxsize, stdin) == NULL)
1959                         len = -1; /* EOF or error */
1960                 else
1961                         len = strlen(command);
1962                 DEINIT_S();
1963                 return len;
1964         }
1965
1966         init_unicode();
1967
1968 // FIXME: audit & improve this
1969         if (maxsize > MAX_LINELEN)
1970                 maxsize = MAX_LINELEN;
1971         S.maxsize = maxsize;
1972
1973         /* With null flags, no other fields are ever used */
1974         state = st ? st : (line_input_t*) &const_int_0;
1975 #if MAX_HISTORY > 0
1976 # if ENABLE_FEATURE_EDITING_SAVEHISTORY
1977         if ((state->flags & SAVE_HISTORY) && state->hist_file)
1978                 if (state->cnt_history == 0)
1979                         load_history(state);
1980 # endif
1981         if (state->flags & DO_HISTORY)
1982                 state->cur_history = state->cnt_history;
1983 #endif
1984
1985         /* prepare before init handlers */
1986         cmdedit_y = 0;  /* quasireal y, not true if line > xt*yt */
1987         command_len = 0;
1988 #if ENABLE_UNICODE_SUPPORT
1989         command_ps = xzalloc(maxsize * sizeof(command_ps[0]));
1990 #else
1991         command_ps = command;
1992         command[0] = '\0';
1993 #endif
1994 #define command command_must_not_be_used
1995
1996         new_settings = initial_settings;
1997         new_settings.c_lflag &= ~ICANON;        /* unbuffered input */
1998         /* Turn off echoing and CTRL-C, so we can trap it */
1999         new_settings.c_lflag &= ~(ECHO | ECHONL | ISIG);
2000         /* Hmm, in linux c_cc[] is not parsed if ICANON is off */
2001         new_settings.c_cc[VMIN] = 1;
2002         new_settings.c_cc[VTIME] = 0;
2003         /* Turn off CTRL-C, so we can trap it */
2004 #ifndef _POSIX_VDISABLE
2005 # define _POSIX_VDISABLE '\0'
2006 #endif
2007         new_settings.c_cc[VINTR] = _POSIX_VDISABLE;
2008         tcsetattr_stdin_TCSANOW(&new_settings);
2009
2010         previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
2011         win_changed(0); /* do initial resizing */
2012 #if ENABLE_USERNAME_OR_HOMEDIR
2013         {
2014                 struct passwd *entry;
2015
2016                 entry = getpwuid(geteuid());
2017                 if (entry) {
2018                         user_buf = xstrdup(entry->pw_name);
2019                         home_pwd_buf = xstrdup(entry->pw_dir);
2020                 }
2021         }
2022 #endif
2023
2024 #if 0
2025         for (i = 0; i <= MAX_HISTORY; i++)
2026                 bb_error_msg("history[%d]:'%s'", i, state->history[i]);
2027         bb_error_msg("cur_history:%d cnt_history:%d", state->cur_history, state->cnt_history);
2028 #endif
2029
2030         /* Print out the command prompt, optionally ask where cursor is */
2031         parse_and_put_prompt(prompt);
2032         ask_terminal();
2033
2034         read_key_buffer[0] = 0;
2035         while (1) {
2036                 /*
2037                  * The emacs and vi modes share much of the code in the big
2038                  * command loop.  Commands entered when in vi's command mode
2039                  * (aka "escape mode") get an extra bit added to distinguish
2040                  * them - this keeps them from being self-inserted. This
2041                  * clutters the big switch a bit, but keeps all the code
2042                  * in one place.
2043                  */
2044                 enum {
2045                         VI_CMDMODE_BIT = 0x40000000,
2046                         /* 0x80000000 bit flags KEYCODE_xxx */
2047                 };
2048                 int32_t ic, ic_raw;
2049
2050                 fflush_all();
2051                 ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
2052
2053 #if ENABLE_FEATURE_EDITING_VI
2054                 newdelflag = 1;
2055                 if (vi_cmdmode) {
2056                         /* btw, since KEYCODE_xxx are all < 0, this doesn't
2057                          * change ic if it contains one of them: */
2058                         ic |= VI_CMDMODE_BIT;
2059                 }
2060 #endif
2061
2062                 switch (ic) {
2063                 case '\n':
2064                 case '\r':
2065                 vi_case('\n'|VI_CMDMODE_BIT:)
2066                 vi_case('\r'|VI_CMDMODE_BIT:)
2067                         /* Enter */
2068                         goto_new_line();
2069                         break_out = 1;
2070                         break;
2071                 case CTRL('A'):
2072                 vi_case('0'|VI_CMDMODE_BIT:)
2073                         /* Control-a -- Beginning of line */
2074                         input_backward(cursor);
2075                         break;
2076                 case CTRL('B'):
2077                 vi_case('h'|VI_CMDMODE_BIT:)
2078                 vi_case('\b'|VI_CMDMODE_BIT:) /* ^H */
2079                 vi_case('\x7f'|VI_CMDMODE_BIT:) /* DEL */
2080                         input_backward(1); /* Move back one character */
2081                         break;
2082                 case CTRL('E'):
2083                 vi_case('$'|VI_CMDMODE_BIT:)
2084                         /* Control-e -- End of line */
2085                         put_till_end_and_adv_cursor();
2086                         break;
2087                 case CTRL('F'):
2088                 vi_case('l'|VI_CMDMODE_BIT:)
2089                 vi_case(' '|VI_CMDMODE_BIT:)
2090                         input_forward(); /* Move forward one character */
2091                         break;
2092                 case '\b':   /* ^H */
2093                 case '\x7f': /* DEL */
2094                         if (!isrtl_str())
2095                                 input_backspace();
2096                         else
2097                                 input_delete(0);
2098                         break;
2099                 case KEYCODE_DELETE:
2100                         if (!isrtl_str())
2101                                 input_delete(0);
2102                         else
2103                                 input_backspace();
2104                         break;
2105 #if ENABLE_FEATURE_TAB_COMPLETION
2106                 case '\t':
2107                         input_tab(&lastWasTab);
2108                         break;
2109 #endif
2110                 case CTRL('K'):
2111                         /* Control-k -- clear to end of line */
2112                         command_ps[cursor] = BB_NUL;
2113                         command_len = cursor;
2114                         printf(SEQ_CLEAR_TILL_END_OF_SCREEN);
2115                         break;
2116                 case CTRL('L'):
2117                 vi_case(CTRL('L')|VI_CMDMODE_BIT:)
2118                         /* Control-l -- clear screen */
2119                         printf(ESC"[H"); /* cursor to top,left */
2120                         redraw(0, command_len - cursor);
2121                         break;
2122 #if MAX_HISTORY > 0
2123                 case CTRL('N'):
2124                 vi_case(CTRL('N')|VI_CMDMODE_BIT:)
2125                 vi_case('j'|VI_CMDMODE_BIT:)
2126                         /* Control-n -- Get next command in history */
2127                         if (get_next_history())
2128                                 goto rewrite_line;
2129                         break;
2130                 case CTRL('P'):
2131                 vi_case(CTRL('P')|VI_CMDMODE_BIT:)
2132                 vi_case('k'|VI_CMDMODE_BIT:)
2133                         /* Control-p -- Get previous command from history */
2134                         if (get_previous_history())
2135                                 goto rewrite_line;
2136                         break;
2137 #endif
2138                 case CTRL('U'):
2139                 vi_case(CTRL('U')|VI_CMDMODE_BIT:)
2140                         /* Control-U -- Clear line before cursor */
2141                         if (cursor) {
2142                                 command_len -= cursor;
2143                                 memmove(command_ps, command_ps + cursor,
2144                                         (command_len + 1) * sizeof(command_ps[0]));
2145                                 redraw(cmdedit_y, command_len);
2146                         }
2147                         break;
2148                 case CTRL('W'):
2149                 vi_case(CTRL('W')|VI_CMDMODE_BIT:)
2150                         /* Control-W -- Remove the last word */
2151                         while (cursor > 0 && BB_isspace(command_ps[cursor-1]))
2152                                 input_backspace();
2153                         while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
2154                                 input_backspace();
2155                         break;
2156
2157 #if ENABLE_FEATURE_EDITING_VI
2158                 case 'i'|VI_CMDMODE_BIT:
2159                         vi_cmdmode = 0;
2160                         break;
2161                 case 'I'|VI_CMDMODE_BIT:
2162                         input_backward(cursor);
2163                         vi_cmdmode = 0;
2164                         break;
2165                 case 'a'|VI_CMDMODE_BIT:
2166                         input_forward();
2167                         vi_cmdmode = 0;
2168                         break;
2169                 case 'A'|VI_CMDMODE_BIT:
2170                         put_till_end_and_adv_cursor();
2171                         vi_cmdmode = 0;
2172                         break;
2173                 case 'x'|VI_CMDMODE_BIT:
2174                         input_delete(1);
2175                         break;
2176                 case 'X'|VI_CMDMODE_BIT:
2177                         if (cursor > 0) {
2178                                 input_backward(1);
2179                                 input_delete(1);
2180                         }
2181                         break;
2182                 case 'W'|VI_CMDMODE_BIT:
2183                         vi_Word_motion(1);
2184                         break;
2185                 case 'w'|VI_CMDMODE_BIT:
2186                         vi_word_motion(1);
2187                         break;
2188                 case 'E'|VI_CMDMODE_BIT:
2189                         vi_End_motion();
2190                         break;
2191                 case 'e'|VI_CMDMODE_BIT:
2192                         vi_end_motion();
2193                         break;
2194                 case 'B'|VI_CMDMODE_BIT:
2195                         vi_Back_motion();
2196                         break;
2197                 case 'b'|VI_CMDMODE_BIT:
2198                         vi_back_motion();
2199                         break;
2200                 case 'C'|VI_CMDMODE_BIT:
2201                         vi_cmdmode = 0;
2202                         /* fall through */
2203                 case 'D'|VI_CMDMODE_BIT:
2204                         goto clear_to_eol;
2205
2206                 case 'c'|VI_CMDMODE_BIT:
2207                         vi_cmdmode = 0;
2208                         /* fall through */
2209                 case 'd'|VI_CMDMODE_BIT: {
2210                         int nc, sc;
2211
2212                         ic = lineedit_read_key(read_key_buffer, timeout);
2213                         if (errno) /* error */
2214                                 goto return_error_indicator;
2215                         if (ic == ic_raw) { /* "cc", "dd" */
2216                                 input_backward(cursor);
2217                                 goto clear_to_eol;
2218                                 break;
2219                         }
2220
2221                         sc = cursor;
2222                         switch (ic) {
2223                         case 'w':
2224                         case 'W':
2225                         case 'e':
2226                         case 'E':
2227                                 switch (ic) {
2228                                 case 'w':   /* "dw", "cw" */
2229                                         vi_word_motion(vi_cmdmode);
2230                                         break;
2231                                 case 'W':   /* 'dW', 'cW' */
2232                                         vi_Word_motion(vi_cmdmode);
2233                                         break;
2234                                 case 'e':   /* 'de', 'ce' */
2235                                         vi_end_motion();
2236                                         input_forward();
2237                                         break;
2238                                 case 'E':   /* 'dE', 'cE' */
2239                                         vi_End_motion();
2240                                         input_forward();
2241                                         break;
2242                                 }
2243                                 nc = cursor;
2244                                 input_backward(cursor - sc);
2245                                 while (nc-- > cursor)
2246                                         input_delete(1);
2247                                 break;
2248                         case 'b':  /* "db", "cb" */
2249                         case 'B':  /* implemented as B */
2250                                 if (ic == 'b')
2251                                         vi_back_motion();
2252                                 else
2253                                         vi_Back_motion();
2254                                 while (sc-- > cursor)
2255                                         input_delete(1);
2256                                 break;
2257                         case ' ':  /* "d ", "c " */
2258                                 input_delete(1);
2259                                 break;
2260                         case '$':  /* "d$", "c$" */
2261  clear_to_eol:
2262                                 while (cursor < command_len)
2263                                         input_delete(1);
2264                                 break;
2265                         }
2266                         break;
2267                 }
2268                 case 'p'|VI_CMDMODE_BIT:
2269                         input_forward();
2270                         /* fallthrough */
2271                 case 'P'|VI_CMDMODE_BIT:
2272                         put();
2273                         break;
2274                 case 'r'|VI_CMDMODE_BIT:
2275 //FIXME: unicode case?
2276                         ic = lineedit_read_key(read_key_buffer, timeout);
2277                         if (errno) /* error */
2278                                 goto return_error_indicator;
2279                         if (ic < ' ' || ic > 255) {
2280                                 beep();
2281                         } else {
2282                                 command_ps[cursor] = ic;
2283                                 bb_putchar(ic);
2284                                 bb_putchar('\b');
2285                         }
2286                         break;
2287                 case '\x1b': /* ESC */
2288                         if (state->flags & VI_MODE) {
2289                                 /* insert mode --> command mode */
2290                                 vi_cmdmode = 1;
2291                                 input_backward(1);
2292                         }
2293                         break;
2294 #endif /* FEATURE_COMMAND_EDITING_VI */
2295
2296 #if MAX_HISTORY > 0
2297                 case KEYCODE_UP:
2298                         if (get_previous_history())
2299                                 goto rewrite_line;
2300                         beep();
2301                         break;
2302                 case KEYCODE_DOWN:
2303                         if (!get_next_history())
2304                                 break;
2305  rewrite_line:
2306                         /* Rewrite the line with the selected history item */
2307                         /* change command */
2308                         command_len = load_string(state->history[state->cur_history] ?
2309                                         state->history[state->cur_history] : "", maxsize);
2310                         /* redraw and go to eol (bol, in vi) */
2311                         redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
2312                         break;
2313 #endif
2314                 case KEYCODE_RIGHT:
2315                         input_forward();
2316                         break;
2317                 case KEYCODE_LEFT:
2318                         input_backward(1);
2319                         break;
2320                 case KEYCODE_CTRL_LEFT:
2321                         ctrl_left();
2322                         break;
2323                 case KEYCODE_CTRL_RIGHT:
2324                         ctrl_right();
2325                         break;
2326                 case KEYCODE_HOME:
2327                         input_backward(cursor);
2328                         break;
2329                 case KEYCODE_END:
2330                         put_till_end_and_adv_cursor();
2331                         break;
2332
2333                 default:
2334                         if (initial_settings.c_cc[VINTR] != 0
2335                          && ic_raw == initial_settings.c_cc[VINTR]
2336                         ) {
2337                                 /* Ctrl-C (usually) - stop gathering input */
2338                                 goto_new_line();
2339                                 command_len = 0;
2340                                 break_out = -1; /* "do not append '\n'" */
2341                                 break;
2342                         }
2343                         if (initial_settings.c_cc[VEOF] != 0
2344                          && ic_raw == initial_settings.c_cc[VEOF]
2345                         ) {
2346                                 /* Ctrl-D (usually) - delete one character,
2347                                  * or exit if len=0 and no chars to delete */
2348                                 if (command_len == 0) {
2349                                         errno = 0;
2350
2351                 case -1: /* error (e.g. EIO when tty is destroyed) */
2352  IF_FEATURE_EDITING_VI(return_error_indicator:)
2353                                         break_out = command_len = -1;
2354                                         break;
2355                                 }
2356                                 input_delete(0);
2357                                 break;
2358                         }
2359 //                      /* Control-V -- force insert of next char */
2360 //                      if (c == CTRL('V')) {
2361 //                              if (safe_read(STDIN_FILENO, &c, 1) < 1)
2362 //                                      goto return_error_indicator;
2363 //                              if (c == 0) {
2364 //                                      beep();
2365 //                                      break;
2366 //                              }
2367 //                      }
2368                         if (ic < ' '
2369                          || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
2370                          || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
2371                         ) {
2372                                 /* If VI_CMDMODE_BIT is set, ic is >= 256
2373                                  * and vi mode ignores unexpected chars.
2374                                  * Otherwise, we are here if ic is a
2375                                  * control char or an unhandled ESC sequence,
2376                                  * which is also ignored.
2377                                  */
2378                                 break;
2379                         }
2380                         if ((int)command_len >= (maxsize - 2)) {
2381                                 /* Not enough space for the char and EOL */
2382                                 break;
2383                         }
2384
2385                         command_len++;
2386                         if (cursor == (command_len - 1)) {
2387                                 /* We are at the end, append */
2388                                 command_ps[cursor] = ic;
2389                                 command_ps[cursor + 1] = BB_NUL;
2390                                 put_cur_glyph_and_inc_cursor();
2391                                 if (unicode_bidi_isrtl(ic))
2392                                         input_backward(1);
2393                         } else {
2394                                 /* In the middle, insert */
2395                                 int sc = cursor;
2396
2397                                 memmove(command_ps + sc + 1, command_ps + sc,
2398                                         (command_len - sc) * sizeof(command_ps[0]));
2399                                 command_ps[sc] = ic;
2400                                 /* is right-to-left char, or neutral one (e.g. comma) was just added to rtl text? */
2401                                 if (!isrtl_str())
2402                                         sc++; /* no */
2403                                 put_till_end_and_adv_cursor();
2404                                 /* to prev x pos + 1 */
2405                                 input_backward(cursor - sc);
2406                         }
2407                         break;
2408                 } /* switch (ic) */
2409
2410                 if (break_out)
2411                         break;
2412
2413 #if ENABLE_FEATURE_TAB_COMPLETION
2414                 if (ic_raw != '\t')
2415                         lastWasTab = 0;
2416 #endif
2417         } /* while (1) */
2418
2419 #if ENABLE_FEATURE_EDITING_ASK_TERMINAL
2420         if (S.sent_ESC_br6n) {
2421                 /* "sleep 1; busybox ash" + hold [Enter] to trigger.
2422                  * We sent "ESC [ 6 n", but got '\n' first, and
2423                  * KEYCODE_CURSOR_POS response is now buffered from terminal.
2424                  * It's bad already and not much can be done with it
2425                  * (it _will_ be visible for the next process to read stdin),
2426                  * but without this delay it even shows up on the screen
2427                  * as garbage because we restore echo settings with tcsetattr
2428                  * before it comes in. UGLY!
2429                  */
2430                 usleep(20*1000);
2431         }
2432 #endif
2433
2434 /* End of bug-catching "command_must_not_be_used" trick */
2435 #undef command
2436
2437 #if ENABLE_UNICODE_SUPPORT
2438         command[0] = '\0';
2439         if (command_len > 0)
2440                 command_len = save_string(command, maxsize - 1);
2441         free(command_ps);
2442 #endif
2443
2444         if (command_len > 0)
2445                 remember_in_history(command);
2446
2447         if (break_out > 0) {
2448                 command[command_len++] = '\n';
2449                 command[command_len] = '\0';
2450         }
2451
2452 #if ENABLE_FEATURE_TAB_COMPLETION
2453         free_tab_completion_data();
2454 #endif
2455
2456         /* restore initial_settings */
2457         tcsetattr_stdin_TCSANOW(&initial_settings);
2458         /* restore SIGWINCH handler */
2459         signal(SIGWINCH, previous_SIGWINCH_handler);
2460         fflush_all();
2461
2462         len = command_len;
2463         DEINIT_S();
2464
2465         return len; /* can't return command_len, DEINIT_S() destroys it */
2466 }
2467
2468 #else  /* !FEATURE_EDITING */
2469
2470 #undef read_line_input
2471 int FAST_FUNC read_line_input(const char* prompt, char* command, int maxsize)
2472 {
2473         fputs(prompt, stdout);
2474         fflush_all();
2475         fgets(command, maxsize, stdin);
2476         return strlen(command);
2477 }
2478
2479 #endif  /* !FEATURE_EDITING */
2480
2481
2482 /*
2483  * Testing
2484  */
2485
2486 #ifdef TEST
2487
2488 #include <locale.h>
2489
2490 const char *applet_name = "debug stuff usage";
2491
2492 int main(int argc, char **argv)
2493 {
2494         char buff[MAX_LINELEN];
2495         char *prompt =
2496 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
2497                 "\\[\\033[32;1m\\]\\u@\\[\\x1b[33;1m\\]\\h:"
2498                 "\\[\\033[34;1m\\]\\w\\[\\033[35;1m\\] "
2499                 "\\!\\[\\e[36;1m\\]\\$ \\[\\E[0m\\]";
2500 #else
2501                 "% ";
2502 #endif
2503
2504         while (1) {
2505                 int l;
2506                 l = read_line_input(prompt, buff);
2507                 if (l <= 0 || buff[l-1] != '\n')
2508                         break;
2509                 buff[l-1] = '\0';
2510                 printf("*** read_line_input() returned line =%s=\n", buff);
2511         }
2512         printf("*** read_line_input() detect ^D\n");
2513         return 0;
2514 }
2515
2516 #endif  /* TEST */