gen/getttyent.c

   1 /*
   2  * Copyright (c) 1999, 2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * Copyright (c) 1989, 1993
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * Redistribution and use in source and binary forms, with or without
  28  * modification, are permitted provided that the following conditions
  29  * are met:
  30  * 1. Redistributions of source code must retain the above copyright
  31  *    notice, this list of conditions and the following disclaimer.
  32  * 2. Redistributions in binary form must reproduce the above copyright
  33  *    notice, this list of conditions and the following disclaimer in the
  34  *    documentation and/or other materials provided with the distribution.
  35  * 3. All advertising materials mentioning features or use of this software
  36  *    must display the following acknowledgement:
  37  *      This product includes software developed by the University of
  38  *      California, Berkeley and its contributors.
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  */
  55
  56 #include "xlocale_private.h"
  57
  58 #include <ttyent.h>
  59 #include <stdio.h>
  60 #include <ctype.h>
  61 #include <string.h>
  62 #include <stdlib.h>
  63 #include <regex.h>
  64 #include <limits.h>
  65
  66 #pragma clang diagnostic push
  67 #pragma clang diagnostic ignored "-Wstrict-prototypes"
  68
  69 static char zapchar;
  70 static FILE *tf;
  71
  72 struct ttyent *
  73 getttynam(tty)
  74         const char *tty;
  75 {
  76         register struct ttyent *t;
  77
  78         setttyent();
  79         while ((t = getttyent()) != NULL)
  80                 if (!strcmp(tty, t->ty_name))
  81                         break;
  82         endttyent();
  83         return (t);
  84 }
  85
  86 static char *skip(), *value();
  87
  88 /*
  89  * 4372480: Support for sequences in the tty name.  Expressions like [000-999]
  90  * for decimal sequences and [0x0-0xf] for hexidecimal sequences causes a
  91  * sequence of all combinations of names to be returned by getttyent().
  92  *
  93  * There is also a slot=nn option, which will cause getttyent() to return
  94  * non-existent ttyent structs until the slot number nn is reached.  Note, slot
  95  * numbers begin at 1.
  96  */
  97 struct seq {
  98         int first;
  99         int count;
 100         int index;
 101         char fmt[NAME_MAX + 17];
 102 };
 103
 104 static const char *brapat = "\\[(.*)]";
 105 static regex_t brapreg;
 106 static const char *decpat = "^([0-9]+)-([0-9]+)$";
 107 static regex_t decpreg;
 108 static const char *hexpat = "^0x([0-9a-f]+)-0x([0-9a-f]+)$";
 109 static regex_t hexpreg;
 110 static struct seq *seq = NULL;
 111 static int slot;
 112
 113 struct ttyent *
 114 getttyent(void)
 115 {
 116         static struct ttyent tty;
 117         static const struct ttyent nonexistent = {
 118                 "\01",  /* this shouldn't match anything */
 119                 NULL,
 120                 NULL,
 121                 0,
 122                 NULL,
 123                 NULL,
 124                 NULL
 125         };
 126         register int c;
 127         register char *p;
 128 #define MAXLINELENGTH   1024
 129         static char *line = NULL;
 130         locale_t loc = __current_locale();
 131         int newslot, hex;
 132         long b, e;
 133         regmatch_t match[3], save, bracket;
 134
 135         if ( line == NULL ) {
 136                 line = malloc(MAXLINELENGTH);
 137                 if( line == NULL )
 138                         return NULL;
 139         }
 140
 141         if (!tf && !setttyent())
 142                 return (NULL);
 143
 144 restart:
 145         if (slot < seq->first) {
 146                 /*
 147                  * the slot= option was set, and we are returning non-existent
 148                  * entries until we catch up.
 149                  */
 150                 slot++;
 151                 return (struct ttyent *)&nonexistent;
 152         }
 153
 154         if (seq->count > 0) {
 155                 /*
 156                  * generate the next tty name; the rest of the tty entries
 157                  * is the same.
 158                  */
 159                 sprintf(tty.ty_name, seq->fmt, seq->index++);
 160                 slot++;
 161                 seq->count--;
 162                 return &tty;
 163         }
 164
 165         if (slot == seq->first) {
 166                 /*
 167                  * this was a regular entry with slot=
 168                  */
 169                 slot++;
 170                 return &tty;
 171         }
 172
 173         for (;;) {
 174                 if (!fgets(p = line, MAXLINELENGTH, tf))
 175                         return (NULL);
 176                 /* skip lines that are too big */
 177                 if (!index(p, '\n')) {
 178                         while ((c = getc(tf)) != '\n' && c != EOF)
 179                                 ;
 180                         continue;
 181                 }
 182                 while (isspace_l(*p, loc))
 183                         ++p;
 184                 if (*p && *p != '#')
 185                         break;
 186         }
 187
 188         zapchar = 0;
 189         tty.ty_name = p;
 190         p = skip(p);
 191         if (!*(tty.ty_getty = p))
 192                 tty.ty_getty = tty.ty_type = NULL;
 193         else {
 194                 p = skip(p);
 195                 if (!*(tty.ty_type = p))
 196                         tty.ty_type = NULL;
 197                 else
 198                         p = skip(p);
 199         }
 200         tty.ty_status = 0;
 201         tty.ty_window = NULL;
 202         tty.ty_onerror = NULL;
 203         tty.ty_onoption = NULL;
 204
 205 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace_l(p[sizeof(e) - 1], loc)
 206 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
 207         newslot = -1;
 208         for (; *p; p = skip(p)) {
 209                 if (scmp(_TTYS_OFF))
 210                         tty.ty_status &= ~TTY_ON;
 211                 else if (scmp(_TTYS_ON))
 212                         tty.ty_status |= TTY_ON;
 213                 else if (scmp(_TTYS_SECURE))
 214                         tty.ty_status |= TTY_SECURE;
 215                 else if (vcmp(_TTYS_WINDOW))
 216                         tty.ty_window = value(p);
 217                 else if (vcmp(_TTYS_ONERROR))
 218                         tty.ty_onerror = value(p);
 219                 else if (vcmp(_TTYS_ONOPTION))
 220                         tty.ty_onoption = value(p);
 221                 else if (vcmp(_TTYS_SLOT)) {
 222                         char *slotstr = value(p);
 223                         if (slotstr)
 224                                 newslot = atoi(slotstr);
 225                 } else
 226                         break;
 227         }
 228
 229         if (zapchar == '#' || *p == '#')
 230                 while ((c = *++p) == ' ' || c == '\t')
 231                         ;
 232         tty.ty_comment = p;
 233         if (*p == 0)
 234                 tty.ty_comment = 0;
 235         if ((p = index(p, '\n')) != NULL)
 236                 *p = '\0';
 237
 238         /* check if tty.tyname has a sequence */
 239         if (regexec(&brapreg, tty.ty_name, 3, match, 0) != 0)
 240                 goto out;
 241
 242         /*
 243          * save the range of the bracketed range, so we can find the strings
 244          * before and after
 245          */
 246         bracket = match[0];
 247         /* use REG_STARTEND to limit matching with the bracketed range */
 248         match[0] = save = match[1];
 249         if (regexec(&decpreg, tty.ty_name, 3, match, REG_STARTEND) == 0) {
 250                 /* a decimal range */
 251                 b = strtol(tty.ty_name + match[1].rm_so, NULL, 10);
 252                 e = strtol(tty.ty_name + match[2].rm_so, NULL, 10);
 253                 hex = 0;
 254         } else {
 255                 match[0] = save;
 256                 if (regexec(&hexpreg, tty.ty_name, 3, match, REG_STARTEND) == 0) {
 257                         /* a hexidecimal range */
 258                         b = strtol(tty.ty_name + match[1].rm_so, NULL, 16);
 259                         e = strtol(tty.ty_name + match[2].rm_so, NULL, 16);
 260                         hex = 1;
 261                 } else
 262                         goto out;
 263         }
 264         if (b > e)      /* skip */
 265                 goto restart;
 266
 267         /* seq->first is already less than slot, so just leave it */
 268         seq->count = (int)(e - b + 1);
 269         seq->index = (int)(b);
 270         /*
 271          * The fmt string contains the characters before the bracket, the
 272          * a format specifier (either decimal or hex) and any characters
 273          * after the bracket.  Note that the length of the lower range is
 274          * use as a minimum digit length, with zero fill, so the format
 275          * specifier will look something like %03d.
 276          */
 277         sprintf(seq->fmt, "%.*s%%0%d%c%s",
 278                 (int)bracket.rm_so, tty.ty_name,
 279                 (int)(match[1].rm_eo - match[1].rm_so),
 280                 hex ? 'x' : 'd',
 281                 tty.ty_name + bracket.rm_eo);
 282
 283 out:
 284         if (newslot > slot) {
 285                 /* set up to skip until newslot */
 286                 seq->first = newslot;
 287                 goto restart;
 288         }
 289         if (seq->count > 0)     /* restart if we are doing a sequence */
 290                 goto restart;
 291         /* regular single value return */
 292         slot++;
 293         return (&tty);
 294 }
 295
 296 #define QUOTED  1
 297
 298 /*
 299  * Skip over the current field, removing quotes, and return a pointer to
 300  * the next field.
 301  */
 302 static char *
 303 skip(p)
 304         register char *p;
 305 {
 306         register char *t;
 307         register int c, q;
 308
 309         for (q = 0, t = p; (c = *p) != '\0'; p++) {
 310                 if (c == '"') {
 311                         q ^= QUOTED;    /* obscure, but nice */
 312                         continue;
 313                 }
 314                 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
 315                         p++;
 316                 *t++ = *p;
 317                 if (q == QUOTED)
 318                         continue;
 319                 if (c == '#') {
 320                         zapchar = c;
 321                         *p = 0;
 322                         break;
 323                 }
 324                 if (c == '\t' || c == ' ' || c == '\n') {
 325                         zapchar = c;
 326                         *p++ = 0;
 327                         while ((c = *p) == '\t' || c == ' ' || c == '\n')
 328                                 p++;
 329                         break;
 330                 }
 331         }
 332         *--t = '\0';
 333         return (p);
 334 }
 335
 336 static char *
 337 value(p)
 338         register char *p;
 339 {
 340
 341         return ((p = index(p, '=')) ? ++p : NULL);
 342 }
 343
 344 int
 345 setttyent()
 346 {
 347
 348         /* initialize seq and the three regexp patterns */
 349         if (!seq) {
 350                 if (regcomp(&brapreg, brapat, REG_EXTENDED) != 0)
 351                         return 0;
 352                 if (regcomp(&decpreg, decpat, REG_EXTENDED) != 0) {
 353                         regfree(&brapreg);
 354                         return 0;
 355                 }
 356                 if (regcomp(&hexpreg, hexpat, REG_EXTENDED | REG_ICASE) != 0) {
 357                         regfree(&decpreg);
 358                         regfree(&brapreg);
 359                         return 0;
 360                 }
 361                 if ((seq = malloc(sizeof(struct seq))) == NULL) {
 362                         regfree(&hexpreg);
 363                         regfree(&decpreg);
 364                         regfree(&brapreg);
 365                         return 0;
 366                 }
 367         }
 368         seq->first = seq->count = 0;
 369         slot = 1;
 370
 371         if (tf) {
 372                 (void)rewind(tf);
 373                 return (1);
 374         } else if ((tf = fopen(_PATH_TTYS, "r")) != NULL)
 375                 return (1);
 376         return (0);
 377 }
 378
 379 int
 380 endttyent()
 381 {
 382         int rval;
 383
 384         if (tf) {
 385                 rval = !(fclose(tf) == EOF);
 386                 tf = NULL;
 387                 return (rval);
 388         }
 389         return (1);
 390 }
 391 #pragma clang diagnostic pop
 392