tty.c

   1 /*@ S-nail - a mail user agent derived from Berkeley Mail.
   2  *@ TTY interaction.
   3  *
   4  * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
   5  * Copyright (c) 2012 - 2014 Steffen "Daode" Nurpmeso <sdaoden@users.sf.net>.
   6  */
   7 /*
   8  * Copyright (c) 1980, 1993
   9  *      The Regents of the University of California.  All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Berkeley and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  */
  39 /* The NCL version is
  40  *
  41  * Copyright (c) 2013 - 2014 Steffen "Daode" Nurpmeso <sdaoden@users.sf.net>.
  42  *
  43  * Permission to use, copy, modify, and/or distribute this software for any
  44  * purpose with or without fee is hereby granted, provided that the above
  45  * copyright notice and this permission notice appear in all copies.
  46  *
  47  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  48  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  49  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  50  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  51  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  52  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  53  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  54  */
  55
  56 #ifndef HAVE_AMALGAMATION
  57 # include "nail.h"
  58 #endif
  59
  60 #ifdef HAVE_READLINE
  61 # include <readline/readline.h>
  62 # ifdef HAVE_HISTORY
  63 #  include <readline/history.h>
  64 # endif
  65 #elif defined HAVE_EDITLINE
  66 # include <histedit.h>
  67 #endif
  68
  69 /* Shared history support macros */
  70 #ifdef HAVE_HISTORY
  71 # define _CL_HISTFILE(S) \
  72 do {\
  73    S = ok_vlook(NAIL_HISTFILE);\
  74    if ((S) != NULL)\
  75       S = fexpand(S, FEXP_LOCAL);\
  76 } while (0)
  77
  78 # define _CL_HISTSIZE(V) \
  79 do {\
  80    char const *__sv = ok_vlook(NAIL_HISTSIZE);\
  81    long __rv;\
  82    if (__sv == NULL || *__sv == '\0' || (__rv = strtol(__sv, NULL, 10)) == 0)\
  83       (V) = HIST_SIZE;\
  84    else if (__rv < 0)\
  85       (V) = 0;\
  86    else\
  87       (V) = __rv;\
  88 } while (0)
  89
  90 # define _CL_CHECK_ADDHIST(S,NOACT) \
  91 do {\
  92    switch (*(S)) {\
  93    case '\0':\
  94    case ' ':\
  95       NOACT;\
  96    default:\
  97       break;\
  98    }\
  99 } while (0)
 100
 101 # define C_HISTORY_SHARED \
 102         char **argv = v;\
 103 \
 104         if (*argv == NULL)\
 105                 goto jlist;\
 106         if (argv[1] != NULL)\
 107                 goto jerr;\
 108         if (asccasecmp(*argv, "show") == 0)\
 109                 goto jlist;\
 110         if (asccasecmp(*argv, "clear") == 0)\
 111                 goto jclear;\
 112 jerr:\
 113         fprintf(stderr, "Synopsis: history: %s\n", tr(431,\
 114       "Either <show> (default) or <clear> the line editor history"));\
 115         v = NULL;\
 116 jleave:\
 117         return (v == NULL ? !STOP : !OKAY); /* xxx 1:bad 0:good -- do some */
 118 #endif /* HAVE_HISTORY */
 119
 120 /* fexpand() flags for expand-on-tab */
 121 #define _CL_TAB_FEXP_FL (FEXP_FULL | FEXP_SILENT | FEXP_MULTIOK)
 122
 123 /*
 124  * Because we have multiple identical implementations, change file layout a bit
 125  * and place the implementations one after the other below the other externals
 126  */
 127
 128 FL bool_t
 129 yorn(char const *msg)
 130 {
 131    char *cp;
 132
 133    if (!(options & OPT_INTERACTIVE))
 134       return TRU1;
 135    do if ((cp = readstr_input(msg, NULL)) == NULL)
 136       return FAL0;
 137    while (*cp != 'y' && *cp != 'Y' && *cp != 'n' && *cp != 'N');
 138    return (*cp == 'y' || *cp == 'Y');
 139 }
 140
 141 FL char *
 142 getuser(char const *query)
 143 {
 144    char *user = NULL;
 145
 146    if (query == NULL)
 147       query = tr(509, "User: ");
 148
 149    if (readline_input(LNED_NONE, query, &termios_state.ts_linebuf,
 150          &termios_state.ts_linesize) >= 0)
 151       user = termios_state.ts_linebuf;
 152    termios_state_reset();
 153    return user;
 154 }
 155
 156 FL char *
 157 getpassword(char const *query) /* FIXME encaps ttystate signal safe */
 158 {
 159    struct termios tios;
 160    char *pass = NULL;
 161
 162    if (query == NULL)
 163       query = tr(510, "Password: ");
 164    fputs(query, stdout);
 165    fflush(stdout);
 166
 167    /*
 168     * FIXME everywhere: tcsetattr() generates SIGTTOU when we're not in
 169     * foreground pgrp, and can fail with EINTR!!
 170     */
 171    if (options & OPT_TTYIN) {
 172       tcgetattr(STDIN_FILENO, &termios_state.ts_tios);
 173       memcpy(&tios, &termios_state.ts_tios, sizeof tios);
 174       termios_state.ts_needs_reset = TRU1;
 175       tios.c_iflag &= ~(ISTRIP);
 176       tios.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);
 177       tcsetattr(STDIN_FILENO, TCSAFLUSH, &tios);
 178    }
 179
 180    if (readline_restart(stdin, &termios_state.ts_linebuf,
 181          &termios_state.ts_linesize, 0) >= 0)
 182       pass = termios_state.ts_linebuf;
 183    termios_state_reset();
 184
 185    if (options & OPT_TTYIN)
 186       fputc('\n', stdout);
 187    return pass;
 188 }
 189
 190 FL bool_t
 191 getcredentials(char **user, char **pass)
 192 {
 193    bool_t rv = TRU1;
 194    char *u = *user, *p = *pass;
 195
 196    if (u == NULL) {
 197       if ((u = getuser(NULL)) == NULL)
 198          rv = FAL0;
 199       else if (p == NULL)
 200          u = savestr(u);
 201       *user = u;
 202    }
 203
 204    if (p == NULL) {
 205       if ((p = getpassword(NULL)) == NULL)
 206          rv = FAL0;
 207       *pass = p;
 208    }
 209    return rv;
 210 }
 211
 212 /*
 213  * readline(3)
 214  */
 215
 216 #ifdef HAVE_READLINE
 217 static sighandler_type  _rl_shup;
 218 static char *           _rl_buf;    /* pre_input() hook: initial line */
 219 static int              _rl_buflen; /* content, and its length */
 220
 221 static int  _rl_pre_input(void);
 222
 223 static int
 224 _rl_pre_input(void)
 225 {
 226    /* Handle leftover data from \ escaped former line */
 227    rl_extend_line_buffer(_rl_buflen + 10);
 228    memcpy(rl_line_buffer, _rl_buf, _rl_buflen + 1);
 229    rl_point = rl_end = _rl_buflen;
 230    rl_pre_input_hook = (rl_hook_func_t*)NULL;
 231    rl_redisplay();
 232    return 0;
 233 }
 234
 235 FL void
 236 tty_init(void)
 237 {
 238 # ifdef HAVE_HISTORY
 239    long hs;
 240    char *v;
 241 # endif
 242
 243    rl_readline_name = UNCONST(uagent);
 244 # ifdef HAVE_HISTORY
 245    _CL_HISTSIZE(hs);
 246    using_history();
 247    stifle_history((int)hs);
 248 # endif
 249    rl_read_init_file(NULL);
 250
 251    /* Because rl_read_init_file() may have introduced yet a different
 252     * history size limit, simply load and incorporate the history, leave
 253     * it up to readline(3) to do the rest */
 254 # ifdef HAVE_HISTORY
 255    _CL_HISTFILE(v);
 256    if (v != NULL)
 257       read_history(v);
 258 # endif
 259 }
 260
 261 FL void
 262 tty_destroy(void)
 263 {
 264 # ifdef HAVE_HISTORY
 265    char *v;
 266
 267    _CL_HISTFILE(v);
 268    if (v != NULL)
 269       write_history(v);
 270 # endif
 271    ;
 272 }
 273
 274 FL void
 275 tty_signal(int sig)
 276 {
 277    sigset_t nset, oset;
 278
 279    switch (sig) {
 280 # ifdef SIGWINCH
 281    case SIGWINCH:
 282       break;
 283 # endif
 284    case SIGHUP:
 285       /* readline(3) doesn't catch it :( */
 286       rl_free_line_state();
 287       rl_cleanup_after_signal();
 288       safe_signal(SIGHUP, _rl_shup);
 289       sigemptyset(&nset);
 290       sigaddset(&nset, sig);
 291       sigprocmask(SIG_UNBLOCK, &nset, &oset);
 292       kill(0, sig);
 293       /* XXX When we come here we'll continue editing, so reestablish
 294        * XXX cannot happen */
 295       sigprocmask(SIG_BLOCK, &oset, (sigset_t*)NULL);
 296       _rl_shup = safe_signal(SIGHUP, &tty_signal);
 297       rl_reset_after_signal();
 298       break;
 299    default:
 300       break;
 301    }
 302 }
 303
 304 FL int
 305 (tty_readline)(char const *prompt, char **linebuf, size_t *linesize, size_t n
 306    SMALLOC_DEBUG_ARGS)
 307 {
 308    int nn;
 309    char *line;
 310
 311    if (n > 0) {
 312       _rl_buf = *linebuf;
 313       _rl_buflen = (int)n;
 314       rl_pre_input_hook = &_rl_pre_input;
 315    }
 316
 317    _rl_shup = safe_signal(SIGHUP, &tty_signal);
 318    line = readline(prompt != NULL ? prompt : "");
 319    safe_signal(SIGHUP, _rl_shup);
 320
 321    if (line == NULL) {
 322       nn = -1;
 323       goto jleave;
 324    }
 325    n = strlen(line);
 326
 327    if (n >= *linesize) {
 328       *linesize = LINESIZE + n + 1;
 329       *linebuf = (srealloc)(*linebuf, *linesize SMALLOC_DEBUG_ARGSCALL);
 330    }
 331    memcpy(*linebuf, line, n);
 332    (free)(line);
 333    (*linebuf)[n] = '\0';
 334    nn = (int)n;
 335 jleave:
 336    return nn;
 337 }
 338
 339 FL void
 340 tty_addhist(char const *s)
 341 {
 342 # ifdef HAVE_HISTORY
 343    _CL_CHECK_ADDHIST(s, goto jleave);
 344    hold_all_sigs();  /* XXX too heavy */
 345    add_history(s);   /* XXX yet we jump away! */
 346    rele_all_sigs();  /* XXX remove jumps */
 347 jleave:
 348 # endif
 349    UNUSED(s);
 350 }
 351
 352 # ifdef HAVE_HISTORY
 353 FL int
 354 c_history(void *v)
 355 {
 356    C_HISTORY_SHARED;
 357
 358 jlist: {
 359         FILE *fp;
 360         char *cp;
 361    HIST_ENTRY **hl;
 362         size_t i, b;
 363
 364         if ((fp = Ftemp(&cp, "Ra", "w+", 0600, 1)) == NULL) {
 365                 perror("tmpfile");
 366                 v = NULL;
 367                 goto jleave;
 368         }
 369         rm(cp);
 370         Ftfree(&cp);
 371
 372    hl = history_list();
 373    i = 0;
 374    if (hl != NULL)
 375       while (hl[i] != NULL)
 376          ++i;
 377
 378    b = 0;
 379    while (i-- > 0) {
 380       size_t sl = strlen(hl[i]->line);
 381                 fprintf(fp, "%4lu. %-50.50s (%4lu+%lu bytes)\n",
 382          (ul_it)i, hl[i]->line, (ul_it)b, (ul_it)sl);
 383       b += sl;
 384    }
 385
 386         page_or_print(fp, i);
 387         Fclose(fp);
 388         }
 389         goto jleave;
 390
 391 jclear:
 392    clear_history();
 393         goto jleave;
 394 }
 395 # endif /* HAVE_HISTORY */
 396 #endif /* HAVE_READLINE */
 397
 398 /*
 399  * BSD editline(3)
 400  */
 401
 402 #ifdef HAVE_EDITLINE
 403 static EditLine *    _el_el;     /* editline(3) handle */
 404 static char const *  _el_prompt; /* Current prompt */
 405 # ifdef HAVE_HISTORY
 406 static History *     _el_hcom;   /* History handle for commline */
 407 # endif
 408
 409 static char const *  _el_getprompt(void);
 410
 411 static char const *
 412 _el_getprompt(void)
 413 {
 414    return _el_prompt;
 415 }
 416
 417 FL void
 418 tty_init(void)
 419 {
 420 # ifdef HAVE_HISTORY
 421    HistEvent he;
 422    long hs;
 423    char *v;
 424 # endif
 425
 426 # ifdef HAVE_HISTORY
 427    _CL_HISTSIZE(hs);
 428    _el_hcom = history_init();
 429    history(_el_hcom, &he, H_SETSIZE, (int)hs);
 430    history(_el_hcom, &he, H_SETUNIQUE, 1);
 431 # endif
 432
 433    _el_el = el_init(uagent, stdin, stdout, stderr);
 434    el_set(_el_el, EL_SIGNAL, 1);
 435    el_set(_el_el, EL_TERMINAL, NULL);
 436    /* Need to set HIST before EDITOR, otherwise it won't work automatic */
 437 # ifdef HAVE_HISTORY
 438    el_set(_el_el, EL_HIST, &history, _el_hcom);
 439 # endif
 440    el_set(_el_el, EL_EDITOR, "emacs");
 441 # ifdef EL_PROMPT_ESC
 442    el_set(_el_el, EL_PROMPT_ESC, &_el_getprompt, '\1');
 443 # else
 444    el_set(_el_el, EL_PROMPT, &_el_getprompt);
 445 # endif
 446 # if 0
 447    el_set(_el_el, EL_ADDFN, "tab_complete",
 448       "editline(3) internal completion function", &_el_file_cpl);
 449    el_set(_el_el, EL_BIND, "^I", "tab_complete", NULL);
 450 # endif
 451 # ifdef HAVE_HISTORY
 452    el_set(_el_el, EL_BIND, "^R", "ed-search-prev-history", NULL);
 453 # endif
 454    el_source(_el_el, NULL); /* Source ~/.editrc */
 455
 456    /* Because el_source() may have introduced yet a different history size
 457     * limit, simply load and incorporate the history, leave it up to
 458     * editline(3) to do the rest */
 459 # ifdef HAVE_HISTORY
 460    _CL_HISTFILE(v);
 461    if (v != NULL)
 462       history(_el_hcom, &he, H_LOAD, v);
 463 # endif
 464 }
 465
 466 FL void
 467 tty_destroy(void)
 468 {
 469 # ifdef HAVE_HISTORY
 470    HistEvent he;
 471    char *v;
 472 # endif
 473
 474    el_end(_el_el);
 475
 476 # ifdef HAVE_HISTORY
 477    _CL_HISTFILE(v);
 478    if (v != NULL)
 479       history(_el_hcom, &he, H_SAVE, v);
 480    history_end(_el_hcom);
 481 # endif
 482 }
 483
 484 FL void
 485 tty_signal(int sig)
 486 {
 487    switch (sig) {
 488 # ifdef SIGWINCH
 489    case SIGWINCH:
 490       el_resize(_el_el);
 491       break;
 492 # endif
 493    default:
 494       break;
 495    }
 496 }
 497
 498 FL int
 499 (tty_readline)(char const *prompt, char **linebuf, size_t *linesize, size_t n
 500    SMALLOC_DEBUG_ARGS)
 501 {
 502    int nn;
 503    char const *line;
 504
 505    _el_prompt = (prompt != NULL) ? prompt : "";
 506    if (n > 0)
 507       el_push(_el_el, *linebuf);
 508    line = el_gets(_el_el, &nn);
 509
 510    if (line == NULL) {
 511       nn = -1;
 512       goto jleave;
 513    }
 514    assert(nn >= 0);
 515    n = (size_t)nn;
 516    if (n > 0 && line[n - 1] == '\n')
 517       nn = (int)--n;
 518
 519    if (n >= *linesize) {
 520       *linesize = LINESIZE + n + 1;
 521       *linebuf = (srealloc)(*linebuf, *linesize SMALLOC_DEBUG_ARGSCALL);
 522    }
 523    memcpy(*linebuf, line, n);
 524    (*linebuf)[n] = '\0';
 525 jleave:
 526    return nn;
 527 }
 528
 529 FL void
 530 tty_addhist(char const *s)
 531 {
 532 # ifdef HAVE_HISTORY
 533    /* Enlarge meaning of unique .. to something that rocks;
 534     * xxx unfortunately this is expensive to do with editline(3)
 535     * xxx maybe it would be better to hook the ptfs instead? */
 536    HistEvent he;
 537    int i;
 538
 539    _CL_CHECK_ADDHIST(s, goto jleave);
 540
 541    hold_all_sigs(); /* XXX too heavy, yet we jump away! */
 542    if (history(_el_hcom, &he, H_GETUNIQUE) < 0 || he.num == 0)
 543       goto jadd;
 544
 545    for (i = history(_el_hcom, &he, H_FIRST); i >= 0;
 546          i = history(_el_hcom, &he, H_NEXT))
 547       if (strcmp(he.str, s) == 0) {
 548          history(_el_hcom, &he, H_DEL, he.num);
 549          break;
 550       }
 551 jadd:
 552    history(_el_hcom, &he, H_ENTER, s);
 553    rele_all_sigs(); /* XXX remove jumps */
 554 jleave:
 555 # endif
 556    UNUSED(s);
 557 }
 558
 559 # ifdef HAVE_HISTORY
 560 FL int
 561 c_history(void *v)
 562 {
 563    C_HISTORY_SHARED;
 564
 565 jlist: {
 566    HistEvent he;
 567         FILE *fp;
 568         char *cp;
 569         size_t i, b;
 570    int x;
 571
 572         if ((fp = Ftemp(&cp, "Ra", "w+", 0600, 1)) == NULL) {
 573                 perror("tmpfile");
 574                 v = NULL;
 575                 goto jleave;
 576         }
 577         rm(cp);
 578         Ftfree(&cp);
 579
 580    i = (size_t)((history(_el_hcom, &he, H_GETSIZE) >= 0) ? he.num : 0);
 581    b = 0;
 582    for (x = history(_el_hcom, &he, H_FIRST); x >= 0;
 583          x = history(_el_hcom, &he, H_NEXT)) {
 584       size_t sl = strlen(he.str);
 585                 fprintf(fp, "%4lu. %-50.50s (%4lu+%lu bytes)\n",
 586          (ul_it)i, he.str, (ul_it)b, (ul_it)sl);
 587       --i;
 588       b += sl;
 589    }
 590
 591         page_or_print(fp, i);
 592         Fclose(fp);
 593         }
 594         goto jleave;
 595
 596 jclear: {
 597    HistEvent he;
 598    history(_el_hcom, &he, H_CLEAR);
 599    }
 600         goto jleave;
 601 }
 602 # endif /* HAVE_HISTORY */
 603 #endif /* HAVE_EDITLINE */
 604
 605 /*
 606  * NCL: our homebrew version (inspired from NetBSD sh(1) / dash(1)s hetio.c).
 607  *
 608  * Only used in interactive mode, simply use STDIN_FILENO as point of interest.
 609  * We do not handle character widths because the terminal must deal with that
 610  * anyway on the one hand, and also wcwidth(3) doesn't support zero-width
 611  * characters by definition on the other.  We're addicted.
 612  *
 613  * To avoid memory leaks etc. with the current codebase that simply longjmp(3)s
 614  * we're forced to use the very same buffer--the one that is passed through to
 615  * us from the outside--to store anything we need, i.e., a `struct cell[]', and
 616  * convert that on-the-fly back to the plain char* result once we're done.
 617  * To simplify our live, use savestr() buffers for all other needed memory
 618  */
 619
 620 /*
 621  * TODO NCL: don't use that stupid .sint=-1 stuff, but simply block all signals
 622  * TODO NCL: during handler de-/installation handling.
 623  */
 624
 625 #ifdef HAVE_NCL
 626 # ifndef MAX_INPUT
 627 #  define MAX_INPUT 255    /* (_POSIX_MAX_INPUT = 255 as of Issue 7 TC1) */
 628 # endif
 629
 630   /* Since we simply fputs(3) the prompt, assume each character requires two
 631    * visual cells -- and we need to restrict the maximum prompt size because
 632    * of MAX_INPUT and our desire to have room for some error message left */
 633 # define _PROMPT_VLEN(P)   (strlen(P) * 2)
 634 # define _PROMPT_MAX       ((MAX_INPUT / 2) + (MAX_INPUT / 4))
 635
 636 union xsighdl {
 637    sighandler_type   shdl; /* Try avoid races by setting */
 638    sl_it             sint; /* .sint=-1 when inactive */
 639 };
 640 CTA(sizeof(sl_it) >= sizeof(sighandler_type));
 641
 642 struct xtios {
 643    struct termios told;
 644    struct termios tnew;
 645 };
 646
 647 struct cell {
 648    wchar_t  wc;
 649    ui_it    count;
 650    char     cbuf[MB_LEN_MAX * 2];   /* .. plus reset shift sequence */
 651 };
 652
 653 struct line {
 654    size_t         cursor;     /* Current cursor position */
 655    size_t         topins;     /* Outermost cursor col set */
 656    union {
 657       char *         cbuf;    /* *x_buf */
 658       struct cell *  cells;
 659    }              line;
 660    struct str     defc;       /* Current default content */
 661    struct str     savec;      /* Saved default content */
 662 # ifdef HAVE_HISTORY
 663    struct hist *  hist;       /* History cursor */
 664 # endif
 665    char const *   prompt;
 666    char const *   nd;         /* Cursor right */
 667    char **        x_buf;      /* Caller pointers */
 668    size_t *       x_bufsize;
 669 };
 670
 671 # ifdef HAVE_HISTORY
 672 struct hist {
 673    struct hist *  older;
 674    struct hist *  younger;
 675    size_t         len;
 676    char           dat[VFIELD_SIZE(sizeof(size_t))];
 677 };
 678 # endif
 679
 680 static union xsighdl _ncl_oint;
 681 static union xsighdl _ncl_oquit;
 682 static union xsighdl _ncl_oterm;
 683 static union xsighdl _ncl_ohup;
 684 static union xsighdl _ncl_otstp;
 685 static union xsighdl _ncl_ottin;
 686 static union xsighdl _ncl_ottou;
 687 static struct xtios  _ncl_tios;
 688 # ifdef HAVE_HISTORY
 689 static struct hist * _ncl_hist;
 690 static struct hist * _ncl_hist_tail;
 691 static size_t        _ncl_hist_size;
 692 static size_t        _ncl_hist_size_max;
 693 static bool_t        _ncl_hist_load;
 694 # endif
 695
 696 static void    _ncl_sigs_up(void);
 697 static void    _ncl_sigs_down(void);
 698
 699 static void    _ncl_term_mode(bool_t raw);
 700
 701 static void    _ncl_check_grow(struct line *l, size_t no SMALLOC_DEBUG_ARGS);
 702 static void    _ncl_bs_eof_dvup(struct cell *cap, size_t i);
 703 static ssize_t _ncl_wboundary(struct line *l, ssize_t dir);
 704 static ssize_t _ncl_cell2dat(struct line *l);
 705 # if defined HAVE_HISTORY || defined HAVE_TABEXPAND
 706 static void    _ncl_cell2save(struct line *l);
 707 # endif
 708
 709 static void    _ncl_khome(struct line *l, bool_t dobell);
 710 static void    _ncl_kend(struct line *l);
 711 static void    _ncl_kbs(struct line *l);
 712 static void    _ncl_kkill(struct line *l, bool_t dobell);
 713 static ssize_t _ncl_keof(struct line *l);
 714 static void    _ncl_kleft(struct line *l);
 715 static void    _ncl_kright(struct line *l);
 716 static void    _ncl_krefresh(struct line *l);
 717 static void    _ncl_kbwddelw(struct line *l);
 718 static void    _ncl_kgow(struct line *l, ssize_t dir);
 719 static void    _ncl_kother(struct line *l, wchar_t wc);
 720 # ifdef HAVE_HISTORY
 721 static size_t  __ncl_khist_shared(struct line *l, struct hist *hp);
 722 static size_t  _ncl_khist(struct line *l, bool_t backwd);
 723 static size_t  _ncl_krhist(struct line *l);
 724 # endif
 725 # ifdef HAVE_TABEXPAND
 726 static size_t  _ncl_kht(struct line *l);
 727 # endif
 728 static ssize_t _ncl_readline(char const *prompt, char **buf, size_t *bufsize,
 729                   size_t len SMALLOC_DEBUG_ARGS);
 730
 731 static void
 732 _ncl_sigs_up(void)
 733 {
 734    if (_ncl_oint.sint == -1)
 735       _ncl_oint.shdl = safe_signal(SIGINT, &tty_signal);
 736    if (_ncl_oquit.sint == -1)
 737       _ncl_oquit.shdl = safe_signal(SIGQUIT, &tty_signal);
 738    if (_ncl_oterm.sint == -1)
 739       _ncl_oterm.shdl = safe_signal(SIGTERM, &tty_signal);
 740    if (_ncl_ohup.sint == -1)
 741       _ncl_ohup.shdl = safe_signal(SIGHUP, &tty_signal);
 742    if (_ncl_otstp.sint == -1)
 743       _ncl_otstp.shdl = safe_signal(SIGTSTP, &tty_signal);
 744    if (_ncl_ottin.sint == -1)
 745       _ncl_ottin.shdl = safe_signal(SIGTTIN, &tty_signal);
 746    if (_ncl_ottou.sint == -1)
 747       _ncl_ottou.shdl  = safe_signal(SIGTTOU, &tty_signal);
 748 }
 749
 750 static void
 751 _ncl_sigs_down(void)
 752 {
 753    /* aaah.. atomic cas would be nice (but isn't it all redundant?) */
 754    sighandler_type st;
 755
 756    if (_ncl_ottou.sint != -1) {
 757       st = _ncl_ottou.shdl, _ncl_ottou.sint = -1;
 758       safe_signal(SIGTTOU, st);
 759    }
 760    if (_ncl_ottin.sint != -1) {
 761       st = _ncl_ottin.shdl, _ncl_ottin.sint = -1;
 762       safe_signal(SIGTTIN, st);
 763    }
 764    if (_ncl_otstp.sint != -1) {
 765       st = _ncl_otstp.shdl, _ncl_otstp.sint = -1;
 766       safe_signal(SIGTSTP, st);
 767    }
 768    if (_ncl_ohup.sint != -1) {
 769       st = _ncl_ohup.shdl, _ncl_ohup.sint = -1;
 770       safe_signal(SIGHUP, st);
 771    }
 772    if (_ncl_oterm.sint != -1) {
 773       st = _ncl_oterm.shdl, _ncl_oterm.sint = -1;
 774       safe_signal(SIGTERM, st);
 775    }
 776    if (_ncl_oquit.sint != -1) {
 777       st = _ncl_oquit.shdl, _ncl_oquit.sint = -1;
 778       safe_signal(SIGQUIT, st);
 779    }
 780    if (_ncl_oint.sint != -1) {
 781       st = _ncl_oint.shdl, _ncl_oint.sint = -1;
 782       safe_signal(SIGINT, st);
 783    }
 784 }
 785
 786 static void
 787 _ncl_term_mode(bool_t raw)
 788 {
 789    struct termios *tiosp = &_ncl_tios.told;
 790
 791    if (!raw)
 792       goto jleave;
 793
 794    /* Always requery the attributes, in case we've been moved from background
 795     * to foreground or however else in between sessions */
 796    tcgetattr(STDIN_FILENO, tiosp);
 797    memcpy(&_ncl_tios.tnew, tiosp, sizeof *tiosp);
 798    tiosp = &_ncl_tios.tnew;
 799    tiosp->c_cc[VMIN] = 1;
 800    tiosp->c_cc[VTIME] = 0;
 801    tiosp->c_iflag &= ~(ISTRIP);
 802    tiosp->c_lflag &= ~(ECHO /*| ECHOE | ECHONL */| ICANON | IEXTEN);
 803 jleave:
 804    tcsetattr(STDIN_FILENO, TCSADRAIN, tiosp);
 805 }
 806
 807 static void
 808 _ncl_check_grow(struct line *l, size_t no SMALLOC_DEBUG_ARGS)
 809 {
 810    size_t i = (l->topins + no) * sizeof(struct cell) + 2 * sizeof(struct cell);
 811
 812    if (i > *l->x_bufsize) {
 813       i <<= 1;
 814       *l->x_bufsize = i;
 815       l->line.cbuf =
 816       *l->x_buf = (srealloc)(*l->x_buf, i SMALLOC_DEBUG_ARGSCALL);
 817    }
 818 }
 819
 820 static void
 821 _ncl_bs_eof_dvup(struct cell *cap, size_t i)
 822 {
 823    size_t j;
 824
 825    if (i > 0)
 826       memmove(cap, cap + 1, i * sizeof(*cap));
 827
 828    /* And.. the (rest of the) visual update */
 829    for (j = 0; j < i; ++j)
 830       fwrite(cap[j].cbuf, sizeof *cap->cbuf, cap[j].count, stdout);
 831    fputs(" \b", stdout);
 832    for (j = 0; j < i; ++j)
 833       putchar('\b');
 834 }
 835
 836 static ssize_t
 837 _ncl_wboundary(struct line *l, ssize_t dir)
 838 {
 839    size_t c = l->cursor, t = l->topins, i;
 840    struct cell *cap;
 841    bool_t anynon;
 842
 843    i = (size_t)-1;
 844    if (dir < 0) {
 845       if (c == 0)
 846          goto jleave;
 847    } else if (c == t)
 848       goto jleave;
 849    else
 850       --t, --c; /* Unsigned wrapping may occur (twice), then */
 851
 852    for (i = 0, cap = l->line.cells, anynon = FAL0;;) {
 853       wchar_t wc = cap[c + dir].wc;
 854       if (iswblank(wc) || iswpunct(wc)) {
 855          if (anynon)
 856             break;
 857       } else
 858          anynon = TRU1;
 859       ++i;
 860       c += dir;
 861       if (dir < 0) {
 862          if (c == 0)
 863             break;
 864       } else if (c == t)
 865          break;
 866    }
 867 jleave:
 868    return (ssize_t)i;
 869 }
 870
 871 static ssize_t
 872 _ncl_cell2dat(struct line *l)
 873 {
 874    size_t len = 0, i;
 875
 876    if (l->topins > 0)
 877       for (i = 0; i < l->topins; ++i) {
 878          struct cell *cap = l->line.cells + i;
 879          memcpy(l->line.cbuf + len, cap->cbuf, cap->count);
 880          len += cap->count;
 881       }
 882    l->line.cbuf[len] = '\0';
 883    return (ssize_t)len;
 884 }
 885
 886 # if defined HAVE_HISTORY || defined HAVE_TABEXPAND
 887 static void
 888 _ncl_cell2save(struct line *l)
 889 {
 890    size_t len, i;
 891    struct cell *cap;
 892
 893    l->savec.s = NULL, l->savec.l = 0;
 894    if (l->topins == 0)
 895       goto jleave;
 896
 897    for (cap = l->line.cells, len = i = 0; i < l->topins; ++cap, ++i)
 898       len += cap->count;
 899
 900    l->savec.l = len;
 901    l->savec.s = salloc(len + 1);
 902
 903    for (cap = l->line.cells, len = i = 0; i < l->topins; ++cap, ++i) {
 904       memcpy(l->savec.s + len, cap->cbuf, cap->count);
 905       len += cap->count;
 906    }
 907    l->savec.s[len] = '\0';
 908 jleave:
 909    ;
 910 }
 911 # endif
 912
 913 static void
 914 _ncl_khome(struct line *l, bool_t dobell)
 915 {
 916    size_t c = l->cursor;
 917
 918    if (c > 0) {
 919       l->cursor = 0;
 920       while (c-- != 0)
 921          putchar('\b');
 922    } else if (dobell)
 923       putchar('\a');
 924 }
 925
 926 static void
 927 _ncl_kend(struct line *l)
 928 {
 929    ssize_t i = (ssize_t)(l->topins - l->cursor);
 930
 931    if (i > 0) {
 932       l->cursor = l->topins;
 933       while (i-- != 0)
 934          fputs(l->nd, stdout);
 935    } else
 936       putchar('\a');
 937 }
 938
 939 static void
 940 _ncl_kbs(struct line *l)
 941 {
 942    ssize_t c = l->cursor, t = l->topins;
 943
 944    if (c > 0) {
 945       putchar('\b');
 946       l->cursor = --c;
 947       l->topins = --t;
 948       t -= c;
 949       _ncl_bs_eof_dvup(l->line.cells + c, t);
 950    } else
 951       putchar('\a');
 952 }
 953
 954 static void
 955 _ncl_kkill(struct line *l, bool_t dobell)
 956 {
 957    size_t j, c = l->cursor, i = (size_t)(l->topins - c);
 958
 959    if (i > 0) {
 960       l->topins = c;
 961       for (j = i; j != 0; --j)
 962          putchar(' ');
 963       for (j = i; j != 0; --j)
 964          putchar('\b');
 965    } else if (dobell)
 966       putchar('\a');
 967 }
 968
 969 static ssize_t
 970 _ncl_keof(struct line *l)
 971 {
 972    size_t c = l->cursor, t = l->topins;
 973    ssize_t i = (ssize_t)(t - c);
 974
 975    if (i > 0) {
 976       l->topins = --t;
 977       _ncl_bs_eof_dvup(l->line.cells + c, --i);
 978    } else if (t == 0 && !ok_blook(ignoreeof)) {
 979       fputs("^D", stdout);
 980       fflush(stdout);
 981       i = -1;
 982    } else {
 983       putchar('\a');
 984       i = 0;
 985    }
 986    return i;
 987 }
 988
 989 static void
 990 _ncl_kleft(struct line *l)
 991 {
 992    if (l->cursor > 0) {
 993       --l->cursor;
 994       putchar('\b');
 995    } else
 996       putchar('\a');
 997 }
 998
 999 static void
1000 _ncl_kright(struct line *l)
1001 {
1002    if (l->cursor < l->topins) {
1003       ++l->cursor;
1004       fputs(l->nd, stdout);
1005    } else
1006       putchar('\a');
1007 }
1008
1009 static void
1010 _ncl_krefresh(struct line *l)
1011 {
1012    struct cell *cap;
1013    size_t i;
1014
1015    putchar('\r');
1016    if (l->prompt != NULL && *l->prompt != '\0')
1017       fputs(l->prompt, stdout);
1018    for (cap = l->line.cells, i = l->topins; i > 0; ++cap, --i)
1019       fwrite(cap->cbuf, sizeof *cap->cbuf, cap->count, stdout);
1020    for (i = l->topins - l->cursor; i > 0; --i)
1021       putchar('\b');
1022 }
1023
1024 static void
1025 _ncl_kbwddelw(struct line *l)
1026 {
1027    ssize_t i;
1028    size_t c = l->cursor, t, j;
1029    struct cell *cap;
1030
1031    i = _ncl_wboundary(l, -1);
1032    if (i <= 0) {
1033       if (i < 0)
1034          putchar('\a');
1035       goto jleave;
1036    }
1037
1038    c = l->cursor - i;
1039    t = l->topins;
1040    l->topins = t - i;
1041    l->cursor = c;
1042    cap = l->line.cells + c;
1043
1044    if (t != l->cursor) {
1045       j = t - c + i;
1046       memmove(cap, cap + i, j * sizeof(*cap));
1047    }
1048
1049    for (j = i; j > 0; --j)
1050       putchar('\b');
1051    for (j = l->topins - c; j > 0; ++cap, --j)
1052       fwrite(cap[0].cbuf, sizeof *cap->cbuf, cap[0].count, stdout);
1053    for (j = i; j > 0; --j)
1054       putchar(' ');
1055    for (j = t - c; j > 0; --j)
1056       putchar('\b');
1057 jleave:
1058    ;
1059 }
1060
1061 static void
1062 _ncl_kgow(struct line *l, ssize_t dir)
1063 {
1064    ssize_t i = _ncl_wboundary(l, dir);
1065    if (i <= 0) {
1066       if (i < 0)
1067          putchar('\a');
1068       goto jleave;
1069    }
1070
1071    if (dir < 0) {
1072       l->cursor -= i;
1073       while (i-- > 0)
1074          putchar('\b');
1075    } else {
1076       l->cursor += i;
1077       while (i-- > 0)
1078          fputs(l->nd, stdout);
1079    }
1080 jleave:
1081    ;
1082 }
1083
1084 static void
1085 _ncl_kother(struct line *l, wchar_t wc)
1086 {
1087    /* Append if at EOL, insert otherwise;
1088     * since we may move around character-wise, always use a fresh ps */
1089    mbstate_t ps;
1090    struct cell cell, *cap;
1091    size_t i, c;
1092
1093    /* First init a cell and see wether we'll really handle this wc */
1094    cell.wc = wc;
1095    memset(&ps, 0, sizeof ps);
1096    i = wcrtomb(cell.cbuf, wc, &ps);
1097    if (i > MB_LEN_MAX)
1098       goto jleave;
1099    cell.count = (ui_it)i;
1100    if (enc_has_state) {
1101       i = wcrtomb(cell.cbuf + i, L'\0', &ps);
1102       if (i == 1)
1103          ;
1104       else if (--i < MB_LEN_MAX)
1105          cell.count += (ui_it)i;
1106       else
1107          goto jleave;
1108    }
1109
1110    /* Yes, we will!  Place it in the array */
1111    c = l->cursor++;
1112    i = l->topins++ - c;
1113    cap = l->line.cells + c;
1114    if (i > 0)
1115       memmove(cap + 1, cap, i * sizeof(cell));
1116    memcpy(cap, &cell, sizeof cell);
1117
1118    /* And update visual */
1119    c = i;
1120    do
1121       fwrite(cap->cbuf, sizeof *cap->cbuf, cap->count, stdout);
1122    while ((++cap, i-- != 0));
1123    while (c-- != 0)
1124       putchar('\b');
1125 jleave:
1126    ;
1127 }
1128
1129 # ifdef HAVE_HISTORY
1130 static size_t
1131 __ncl_khist_shared(struct line *l, struct hist *hp)
1132 {
1133    size_t rv;
1134
1135    if ((l->hist = hp) != NULL) {
1136       l->defc.s = savestrbuf(hp->dat, hp->len);
1137       rv =
1138       l->defc.l = hp->len;
1139       if (l->topins > 0) {
1140          _ncl_khome(l, FAL0);
1141          _ncl_kkill(l, FAL0);
1142       }
1143    } else {
1144       putchar('\a');
1145       rv = 0;
1146    }
1147    return rv;
1148 }
1149
1150 static size_t
1151 _ncl_khist(struct line *l, bool_t backwd)
1152 {
1153    struct hist *hp;
1154
1155    /* If we're not in history mode yet, save line content;
1156     * also, disallow forward search, then, and, of course, bail unless we
1157     * do have any history at all */
1158    if ((hp = l->hist) == NULL) {
1159       if (!backwd)
1160          goto jleave;
1161       if ((hp = _ncl_hist) == NULL)
1162          goto jleave;
1163       _ncl_cell2save(l);
1164       goto jleave;
1165    }
1166
1167    hp = backwd ? hp->older : hp->younger;
1168 jleave:
1169    return __ncl_khist_shared(l, hp);
1170 }
1171
1172 static size_t
1173 _ncl_krhist(struct line *l)
1174 {
1175    struct str orig_savec;
1176    struct hist *hp = NULL;
1177
1178    /* We cannot complete an empty line */
1179    if (l->topins == 0) {
1180       /* XXX The upcoming hard reset would restore a set savec buffer,
1181        * XXX so forcefully reset that.  A cleaner solution would be to
1182        * XXX reset it whenever a restore is no longer desired */
1183       l->savec.s = NULL, l->savec.l = 0;
1184       goto jleave;
1185    }
1186    if ((hp = l->hist) == NULL) {
1187       if ((hp = _ncl_hist) == NULL)
1188          goto jleave;
1189       orig_savec.s = NULL;
1190       orig_savec.l = 0; /* silence CC */
1191    } else if ((hp = hp->older) == NULL)
1192       goto jleave;
1193    else
1194       orig_savec = l->savec;
1195
1196    if (orig_savec.s == NULL)
1197       _ncl_cell2save(l);
1198    for (; hp != NULL; hp = hp->older)
1199       if (is_prefix(l->savec.s, hp->dat))
1200          break;
1201    if (orig_savec.s != NULL)
1202       l->savec = orig_savec;
1203 jleave:
1204    return __ncl_khist_shared(l, hp);
1205 }
1206 # endif
1207
1208 # ifdef HAVE_TABEXPAND
1209 static size_t
1210 _ncl_kht(struct line *l)
1211 {
1212    struct str orig, bot, topp, sub, exp;
1213    struct cell *cword, *ctop, *cx;
1214    bool_t set_savec = FAL0;
1215    size_t rv = 0;
1216
1217    /* We cannot expand an empty line */
1218    if (l->topins == 0)
1219       goto jleave;
1220
1221    /* Get plain line data; if this is the first expansion/xy, update the
1222     * very original content so that ^G gets the origin back */
1223    orig = l->savec;
1224    _ncl_cell2save(l);
1225    exp = l->savec;
1226    if (orig.s != NULL)
1227       l->savec = orig;
1228    else
1229       set_savec = TRU1;
1230    orig = exp;
1231
1232    cword = l->line.cells;
1233    ctop = cword + l->cursor;
1234
1235    /* topp: separate data right of cursor */
1236    if ((cx = cword + l->topins) != ctop) {
1237       for (rv = 0; cx > ctop; --cx)
1238          rv += cx->count;
1239       topp.l = rv;
1240       topp.s = orig.s + orig.l - rv;
1241    } else
1242       topp.s = NULL, topp.l = 0;
1243
1244    /* bot, sub: we cannot expand the entire data left of cursor, but only
1245     * the last "word", so separate them */
1246    while (cx > cword && !iswspace(cx[-1].wc))
1247       --cx;
1248    for (rv = 0; cword < cx; ++cword)
1249       rv += cword->count;
1250    sub =
1251    bot = orig;
1252    bot.l = rv;
1253    sub.s += rv;
1254    sub.l -= rv;
1255    sub.l -= topp.l;
1256
1257    if (sub.l > 0) {
1258       sub.s = savestrbuf(sub.s, sub.l);
1259       /* TODO there is a TODO note upon fexpand() with multi-return;
1260        * TODO if that will change, the if() below can be simplified */
1261       /* Super-Heavy-Metal: block all sigs, avoid leaks on jump */
1262       hold_all_sigs();
1263       exp.s = fexpand(sub.s, _CL_TAB_FEXP_FL);
1264       rele_all_sigs();
1265
1266       if (exp.s != NULL && (exp.l = strlen(exp.s)) > 0 &&
1267             (exp.l != sub.l || strcmp(exp.s, sub.s))) {
1268          /* Cramp expansion length to MAX_INPUT, or 255 if not defined.
1269           * Take care to take *prompt* into account, since we don't know
1270           * anything about it's visual length (fputs(3) is used), simply
1271           * assume each character requires two columns */
1272          /* TODO the problem is that we loose control otherwise; in the best
1273           * TODO case the user can control via ^A and ^K etc., but be safe;
1274           * TODO we cannot simply adjust fexpand() because we don't know how
1275           * TODO that is implemented...  The real solution would be to check
1276           * TODO wether we fit on a line, and start a pager if not.
1277           * TODO However, that should be part of a real tab-COMPLETION, then,
1278           * TODO i.e., don't EXPAND, but SHOW COMPLETIONS, page-wise if needed.
1279           * TODO And: MAX_INPUT is dynamic: pathconf(2), _SC_MAX_INPUT */
1280          rv = (l->prompt != NULL) ? _PROMPT_VLEN(l->prompt) : 0;
1281          if (rv + bot.l + exp.l + topp.l >= MAX_INPUT) {
1282             char const e1[] = "[maximum line size exceeded]";
1283             exp.s = UNCONST(e1);
1284             exp.l = sizeof(e1) - 1;
1285             topp.l = 0;
1286             if (rv + bot.l + exp.l >= MAX_INPUT)
1287                bot.l = 0;
1288             if (rv + exp.l >= MAX_INPUT) {
1289                char const e2[] = "[ERR]";
1290                exp.s = UNCONST(e2);
1291                exp.l = sizeof(e2) - 1;
1292             }
1293          }
1294          orig.l = bot.l + exp.l + topp.l;
1295          orig.s = salloc(orig.l + 1 + 5);
1296          if ((rv = bot.l) > 0)
1297             memcpy(orig.s, bot.s, rv);
1298          memcpy(orig.s + rv, exp.s, exp.l);
1299          rv += exp.l;
1300          if (topp.l > 0) {
1301             memcpy(orig.s + rv, topp.s, topp.l);
1302             rv += topp.l;
1303          }
1304          orig.s[rv] = '\0';
1305
1306          l->defc = orig;
1307          _ncl_khome(l, FAL0);
1308          _ncl_kkill(l, FAL0);
1309          goto jleave;
1310       }
1311    }
1312
1313    /* If we've provided a default content, but failed to expand, there is
1314     * nothing we can "revert to": drop that default again */
1315    if (set_savec)
1316       l->savec.s = NULL, l->savec.l = 0;
1317    rv = 0;
1318 jleave:
1319    return rv;
1320 }
1321 # endif /* HAVE_TABEXPAND */
1322
1323 static ssize_t
1324 _ncl_readline(char const *prompt, char **buf, size_t *bufsize, size_t len
1325    SMALLOC_DEBUG_ARGS)
1326 {
1327    /* We want to save code, yet we may have to incorporate a lines'
1328     * default content and / or default input to switch back to after some
1329     * history movement; let "len > 0" mean "have to display some data
1330     * buffer", and only otherwise read(2) it */
1331    mbstate_t ps[2];
1332    struct line l;
1333    char cbuf_base[MB_LEN_MAX * 2], *cbuf, *cbufp;
1334    wchar_t wc;
1335    ssize_t rv;
1336    ui32_t maybe_cursor;
1337
1338    memset(&l, 0, sizeof l);
1339    l.line.cbuf = *buf;
1340    if (len != 0) {
1341       l.defc.s = savestrbuf(*buf, len);
1342       l.defc.l = len;
1343    }
1344    if ((l.prompt = prompt) != NULL && _PROMPT_VLEN(prompt) > _PROMPT_MAX)
1345       l.prompt = prompt = "?ERR?";
1346    /* TODO *l.nd=='\0' only because we have no value-cache -> see acmava.c */
1347    if ((l.nd = ok_vlook(line_editor_cursor_right)) == NULL || *l.nd == '\0')
1348       l.nd = "\033[C"; /* XXX no "magic" constant */
1349    l.x_buf = buf;
1350    l.x_bufsize = bufsize;
1351
1352    if (prompt != NULL && *prompt != '\0') {
1353       fputs(prompt, stdout);
1354       fflush(stdout);
1355    }
1356 jrestart:
1357    memset(ps, 0, sizeof ps);
1358    maybe_cursor = 0;
1359    /* TODO: NCL: we should output the reset sequence when we jrestart:
1360     * TODO: NCL: if we are using a stateful encoding? !
1361     * TODO: NCL: in short: this is not yet well understood */
1362    for (;;) {
1363       _ncl_check_grow(&l, len SMALLOC_DEBUG_ARGSCALL);
1364
1365       /* Normal read(2)?  Else buffer-takeover: speed this one up */
1366       if (len == 0)
1367          cbufp =
1368          cbuf = cbuf_base;
1369       else {
1370          assert(l.defc.l > 0 && l.defc.s != NULL);
1371          cbufp =
1372          cbuf = l.defc.s + (l.defc.l - len);
1373          cbufp += len;
1374       }
1375
1376       /* Read in the next complete multibyte character */
1377       for (;;) {
1378          if (len == 0) {
1379             if ((rv = read(STDIN_FILENO, cbufp, 1)) < 1) {
1380                if (errno == EINTR) /* xxx #if !SA_RESTART ? */
1381                   continue;
1382                goto jleave;
1383             }
1384             ++cbufp;
1385          }
1386
1387          /* Ach! the ISO C multibyte handling!
1388           * Encodings with locking shift states cannot really be helped, since
1389           * it is impossible to only query the shift state, as opposed to the
1390           * entire shift state + character pair (via ISO C functions) */
1391          rv = (ssize_t)mbrtowc(&wc, cbuf, (size_t)(cbufp - cbuf), ps + 0);
1392          if (rv <= 0) {
1393             /* Any error during take-over can only result in a hard reset;
1394              * Otherwise, if it's a hard error, or if too many redundant shift
1395              * sequences overflow our buffer, also perform a hard reset */
1396             if (len != 0 || rv == -1 ||
1397                   sizeof cbuf_base == (size_t)(cbufp - cbuf)) {
1398                l.savec.s = l.defc.s = NULL,
1399                l.savec.l = l.defc.l = len = 0;
1400                putchar('\a');
1401                wc = 'G';
1402                goto jreset;
1403             }
1404             /* Otherwise, due to the way we deal with the buffer, we need to
1405              * restore the mbstate_t from before this conversion */
1406             ps[0] = ps[1];
1407             continue;
1408          }
1409
1410          if (len != 0 && (len -= (size_t)rv) == 0)
1411             l.defc.s = NULL, l.defc.l = 0;
1412          ps[1] = ps[0];
1413          break;
1414       }
1415
1416       /* Don't interpret control bytes during buffer take-over */
1417       if (cbuf != cbuf_base)
1418          goto jprint;
1419       switch (wc) {
1420       case 'A' ^ 0x40: /* cursor home */
1421          _ncl_khome(&l, TRU1);
1422          break;
1423 j_b:
1424       case 'B' ^ 0x40: /* backward character */
1425          _ncl_kleft(&l);
1426          break;
1427       /* 'C': interrupt (CTRL-C) */
1428       case 'D' ^ 0x40: /* delete char forward if any, else EOF */
1429          if ((rv = _ncl_keof(&l)) < 0)
1430             goto jleave;
1431          break;
1432       case 'E' ^ 0x40: /* end of line */
1433          _ncl_kend(&l);
1434          break;
1435 j_f:
1436       case 'F' ^ 0x40: /* forward character */
1437          _ncl_kright(&l);
1438          break;
1439       /* 'G' below */
1440       case 'H' ^ 0x40: /* backspace */
1441       case '\177':
1442          _ncl_kbs(&l);
1443          break;
1444       case 'I' ^ 0x40: /* horizontal tab */
1445 # ifdef HAVE_TABEXPAND
1446          if ((len = _ncl_kht(&l)) > 0)
1447             goto jrestart;
1448 # endif
1449          goto jbell;
1450       case 'J' ^ 0x40: /* NL (\n) */
1451          goto jdone;
1452       case 'G' ^ 0x40: /* full reset */
1453 jreset:
1454          /* FALLTHRU */
1455       case 'U' ^ 0x40: /* ^U: ^A + ^K */
1456          _ncl_khome(&l, FAL0);
1457          /* FALLTHRU */
1458       case 'K' ^ 0x40: /* kill from cursor to end of line */
1459          _ncl_kkill(&l, (wc == ('K' ^ 0x40) || l.topins == 0));
1460          /* (Handle full reset?) */
1461          if (wc == ('G' ^ 0x40)) {
1462 # ifdef HAVE_HISTORY
1463             l.hist = NULL;
1464 # endif
1465             if ((len = l.savec.l) != 0) {
1466                l.defc = l.savec;
1467                l.savec.s = NULL, l.savec.l = 0;
1468             } else
1469                len = l.defc.l;
1470          }
1471          fflush(stdout);
1472          goto jrestart;
1473       case 'L' ^ 0x40: /* repaint line */
1474          _ncl_krefresh(&l);
1475          break;
1476       /* 'M': CR (\r) */
1477 j_n:
1478       case 'N' ^ 0x40: /* history next */
1479 # ifdef HAVE_HISTORY
1480          if (l.hist == NULL)
1481             goto jbell;
1482          if ((len = _ncl_khist(&l, FAL0)) > 0)
1483             goto jrestart;
1484          wc = 'G' ^ 0x40;
1485          goto jreset;
1486 # else
1487          goto jbell;
1488 # endif
1489       /* 'O' */
1490 j_p:
1491       case 'P' ^ 0x40: /* history previous */
1492 # ifdef HAVE_HISTORY
1493          if ((len = _ncl_khist(&l, TRU1)) > 0)
1494             goto jrestart;
1495          wc = 'G' ^ 0x40;
1496          goto jreset;
1497 # else
1498          goto jbell;
1499 # endif
1500       /* 'Q': no code */
1501       case 'R' ^ 0x40: /* reverse history search */
1502 # ifdef HAVE_HISTORY
1503          if ((len = _ncl_krhist(&l)) > 0)
1504             goto jrestart;
1505          wc = 'G' ^ 0x40;
1506          goto jreset;
1507 # else
1508          goto jbell;
1509 # endif
1510       /* 'S': no code */
1511       /* 'U' above */
1512       /*case 'V' ^ 0x40: TODO*/ /* forward delete "word" */
1513       case 'W' ^ 0x40: /* backward delete "word" */
1514          _ncl_kbwddelw(&l);
1515          break;
1516       case 'X' ^ 0x40: /* move cursor forward "word" */
1517          _ncl_kgow(&l, +1);
1518          break;
1519       case 'Y' ^ 0x40: /* move cursor backward "word" */
1520          _ncl_kgow(&l, -1);
1521          break;
1522       /* 'Z': suspend (CTRL-Z) */
1523       case 0x1B:
1524          if (maybe_cursor++ != 0)
1525             goto jreset;
1526          continue;
1527       default:
1528          /* XXX Handle usual ^[[[ABCD] cursor keys -- UGLY, "MAGIC", INFLEX */
1529          if (maybe_cursor > 0) {
1530             if (++maybe_cursor == 2) {
1531                if (wc == L'[')
1532                   continue;
1533                maybe_cursor = 0;
1534             } else {
1535                maybe_cursor = 0;
1536                switch (wc) {
1537                case L'A':  goto j_p;
1538                case L'B':  goto j_n;
1539                case L'C':  goto j_f;
1540                case L'D':  goto j_b;
1541                }
1542                _ncl_kother(&l, L'[');
1543             }
1544          }
1545 jprint:
1546          if (iswprint(wc)) {
1547             _ncl_kother(&l, wc);
1548             /* Don't clear the history during takeover..
1549              * ..and also avoid fflush()ing unless we've
1550              * worked the entire buffer */
1551             if (len > 0)
1552                continue;
1553 # ifdef HAVE_HISTORY
1554             if (cbuf == cbuf_base)
1555                l.hist = NULL;
1556 # endif
1557          } else {
1558 jbell:
1559             putchar('\a');
1560          }
1561          break;
1562       }
1563       fflush(stdout);
1564    }
1565
1566    /* We have a completed input line, convert the struct cell data to its
1567     * plain character equivalent */
1568 jdone:
1569    putchar('\n');
1570    fflush(stdout);
1571    len = _ncl_cell2dat(&l);
1572    rv = (ssize_t)len;
1573 jleave:
1574    return rv;
1575 }
1576
1577 FL void
1578 tty_init(void)
1579 {
1580 # ifdef HAVE_HISTORY
1581    long hs;
1582    char *v, *lbuf;
1583    FILE *f;
1584    size_t lsize, cnt, llen;
1585 # endif
1586
1587    _ncl_oint.sint = _ncl_oquit.sint = _ncl_oterm.sint =
1588    _ncl_ohup.sint = _ncl_otstp.sint = _ncl_ottin.sint =
1589    _ncl_ottou.sint = -1;
1590
1591 # ifdef HAVE_HISTORY
1592    _CL_HISTSIZE(hs);
1593    _ncl_hist_size = 0;
1594    _ncl_hist_size_max = hs;
1595    if (hs == 0)
1596       goto jleave;
1597
1598    _CL_HISTFILE(v);
1599    if (v == NULL)
1600       goto jleave;
1601
1602    hold_all_sigs(); /* XXX too heavy, yet we may jump even here!? */
1603    f = fopen(v, "r"); /* TODO HISTFILE LOAD: use linebuf pool */
1604    if (f == NULL)
1605       goto jdone;
1606
1607    lbuf = NULL;
1608    lsize = 0;
1609    cnt = fsize(f);
1610    while (fgetline(&lbuf, &lsize, &cnt, &llen, f, FAL0) != NULL) {
1611       if (llen > 0 && lbuf[llen - 1] == '\n')
1612          lbuf[--llen] = '\0';
1613       if (llen == 0 || lbuf[0] == '#') /* xxx comments? noone! */
1614          continue;
1615       _ncl_hist_load = TRU1;
1616       tty_addhist(lbuf);
1617       _ncl_hist_load = FAL0;
1618    }
1619    if (lbuf != NULL)
1620       free(lbuf);
1621
1622    fclose(f);
1623 jdone:
1624    rele_all_sigs(); /* XXX remove jumps */
1625 jleave:
1626 # endif /* HAVE_HISTORY */
1627    ;
1628 }
1629
1630 FL void
1631 tty_destroy(void)
1632 {
1633 # ifdef HAVE_HISTORY
1634    long hs;
1635    char *v;
1636    struct hist *hp;
1637    FILE *f;
1638
1639    _CL_HISTSIZE(hs);
1640    if (hs == 0)
1641       goto jleave;
1642
1643    _CL_HISTFILE(v);
1644    if (v == NULL)
1645       goto jleave;
1646
1647    if ((hp = _ncl_hist) != NULL)
1648       while (hp->older != NULL && hs-- != 0)
1649          hp = hp->older;
1650
1651    hold_all_sigs(); /* TODO too heavy, yet we may jump even here!? */
1652    f = fopen(v, "w"); /* TODO temporary + rename?! */
1653    if (f == NULL)
1654       goto jdone;
1655    if (fchmod(fileno(f), S_IRUSR | S_IWUSR) != 0)
1656       goto jclose;
1657
1658    for (; hp != NULL; hp = hp->younger) {
1659       fwrite(hp->dat, sizeof *hp->dat, hp->len, f);
1660       putc('\n', f);
1661    }
1662 jclose:
1663    fclose(f);
1664 jdone:
1665    rele_all_sigs(); /* XXX remove jumps */
1666 jleave:
1667 # endif /* HAVE_HISTORY */
1668    ;
1669 }
1670
1671 FL void
1672 tty_signal(int sig)
1673 {
1674    sigset_t nset, oset;
1675
1676    switch (sig) {
1677    case SIGWINCH:
1678       /* We don't deal with SIGWINCH, yet get called from main.c */
1679       break;
1680    default:
1681       _ncl_term_mode(FAL0);
1682       _ncl_sigs_down();
1683       sigemptyset(&nset);
1684       sigaddset(&nset, sig);
1685       sigprocmask(SIG_UNBLOCK, &nset, &oset);
1686       kill(0, sig);
1687       /* When we come here we'll continue editing, so reestablish */
1688       sigprocmask(SIG_BLOCK, &oset, (sigset_t*)NULL);
1689       _ncl_sigs_up();
1690       _ncl_term_mode(TRU1);
1691       break;
1692    }
1693 }
1694
1695 FL int
1696 (tty_readline)(char const *prompt, char **linebuf, size_t *linesize, size_t n
1697    SMALLOC_DEBUG_ARGS)
1698 {
1699    ssize_t nn;
1700
1701    /* Of course we have races here, but they cannot be avoided on POSIX
1702     * (except by even *more* actions) */
1703    _ncl_sigs_up();
1704    _ncl_term_mode(TRU1);
1705    nn = _ncl_readline(prompt, linebuf, linesize, n SMALLOC_DEBUG_ARGSCALL);
1706    _ncl_term_mode(FAL0);
1707    _ncl_sigs_down();
1708
1709    return (int)nn;
1710 }
1711
1712 FL void
1713 tty_addhist(char const *s)
1714 {
1715 # ifdef HAVE_HISTORY
1716    /* Super-Heavy-Metal: block all sigs, avoid leaks+ on jump */
1717    size_t l = strlen(s);
1718    struct hist *h, *o, *y;
1719
1720    if (_ncl_hist_size_max == 0)
1721       goto j_leave;
1722    _CL_CHECK_ADDHIST(s, goto j_leave);
1723
1724    /* Eliminating duplicates is expensive, but simply inacceptable so
1725     * during the load of a potentially large history file! */
1726    if (!_ncl_hist_load)
1727       for (h = _ncl_hist; h != NULL; h = h->older)
1728          if (h->len == l && !strcmp(h->dat, s)) {
1729             hold_all_sigs(); /* TODO */
1730             o = h->older;
1731             y = h->younger;
1732             if (o != NULL)
1733                o->younger = y;
1734             else
1735                _ncl_hist_tail = y;
1736             if (y != NULL)
1737                y->older = o;
1738             else
1739                _ncl_hist = o;
1740             goto jleave;
1741          }
1742    hold_all_sigs();
1743
1744    ++_ncl_hist_size;
1745    if (!_ncl_hist_load && _ncl_hist_size > _ncl_hist_size_max) {
1746       --_ncl_hist_size;
1747       if ((h = _ncl_hist_tail) != NULL) {
1748          if ((_ncl_hist_tail = h->younger) == NULL)
1749             _ncl_hist = NULL;
1750          else
1751             _ncl_hist_tail->older = NULL;
1752          free(h);
1753       }
1754    }
1755
1756    h = smalloc((sizeof(struct hist) - VFIELD_SIZEOF(struct hist, dat)) + l +1);
1757    h->len = l;
1758    memcpy(h->dat, s, l +1);
1759 jleave:
1760    if ((h->older = _ncl_hist) != NULL)
1761       _ncl_hist->younger = h;
1762    else
1763       _ncl_hist_tail = h;
1764    h->younger = NULL;
1765    _ncl_hist = h;
1766
1767    rele_all_sigs();
1768 j_leave:
1769 # endif
1770    UNUSED(s);
1771 }
1772
1773 # ifdef HAVE_HISTORY
1774 FL int
1775 c_history(void *v)
1776 {
1777    C_HISTORY_SHARED;
1778
1779 jlist: {
1780         FILE *fp;
1781         char *cp;
1782         size_t i, b;
1783    struct hist *h;
1784
1785         if (_ncl_hist == NULL)
1786       goto jleave;
1787
1788         if ((fp = Ftemp(&cp, "Ra", "w+", 0600, 1)) == NULL) {
1789                 perror("tmpfile");
1790                 v = NULL;
1791                 goto jleave;
1792         }
1793         rm(cp);
1794         Ftfree(&cp);
1795
1796    i = _ncl_hist_size;
1797    b = 0;
1798         for (h = _ncl_hist; h != NULL; --i, b += h->len, h = h->older)
1799                 fprintf(fp, "%4lu. %-50.50s (%4lu+%lu bytes)\n",
1800          (ul_it)i, h->dat, (ul_it)b, (ul_it)h->len);
1801
1802         page_or_print(fp, i);
1803         Fclose(fp);
1804         }
1805         goto jleave;
1806
1807 jclear: {
1808    struct hist *h;
1809         while ((h = _ncl_hist) != NULL) {
1810                 _ncl_hist = h->older;
1811                 free(h);
1812         }
1813    _ncl_hist_tail = NULL;
1814    _ncl_hist_size = 0;
1815    }
1816         goto jleave;
1817 }
1818 # endif /* HAVE_HISTORY */
1819 #endif /* HAVE_NCL */
1820
1821 /*
1822  * The really-nothing-at-all implementation
1823  */
1824
1825 #if !defined HAVE_READLINE && !defined HAVE_EDITLINE && !defined HAVE_NCL
1826 FL void
1827 tty_init(void)
1828 {}
1829
1830 FL void
1831 tty_destroy(void)
1832 {}
1833
1834 FL void
1835 tty_signal(int sig)
1836 {
1837    UNUSED(sig);
1838 }
1839
1840 FL int
1841 (tty_readline)(char const *prompt, char **linebuf, size_t *linesize, size_t n
1842    SMALLOC_DEBUG_ARGS)
1843 {
1844    /*
1845     * TODO The nothing-at-all tty layer even forces re-entering all the
1846     * TODO original data when re-editing a field
1847     */
1848    bool_t doffl = FAL0;
1849
1850    if (prompt != NULL && *prompt != '\0') {
1851       fputs(prompt, stdout);
1852       doffl = TRU1;
1853    }
1854    if (n > 0) {
1855       fprintf(stdout, tr(511, "{former content: %.*s} "), (int)n, *linebuf);
1856       n = 0;
1857       doffl = TRU1;
1858    }
1859    if (doffl)
1860       fflush(stdout);
1861    return (readline_restart)(stdin, linebuf, linesize,n SMALLOC_DEBUG_ARGSCALL);
1862 }
1863
1864 FL void
1865 tty_addhist(char const *s)
1866 {
1867    UNUSED(s);
1868 }
1869 #endif /* nothing at all */
1870
1871 /* vim:set fenc=utf-8:s-it-mode */