contrib/bind-9.3/lib/isc/lex.c

   1 /*
   2  * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1998-2003  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: lex.c,v 1.66.2.6.2.8 2004/08/28 06:25:21 marka Exp $ */
  19
  20 #include <config.h>
  21
  22 #include <ctype.h>
  23 #include <errno.h>
  24 #include <stdlib.h>
  25
  26 #include <isc/buffer.h>
  27 #include <isc/file.h>
  28 #include <isc/lex.h>
  29 #include <isc/mem.h>
  30 #include <isc/msgs.h>
  31 #include <isc/parseint.h>
  32 #include <isc/print.h>
  33 #include <isc/stdio.h>
  34 #include <isc/string.h>
  35 #include <isc/util.h>
  36
  37 typedef struct inputsource {
  38         isc_result_t                    result;
  39         isc_boolean_t                   is_file;
  40         isc_boolean_t                   need_close;
  41         isc_boolean_t                   at_eof;
  42         isc_buffer_t *                  pushback;
  43         unsigned int                    ignored;
  44         void *                          input;
  45         char *                          name;
  46         unsigned long                   line;
  47         unsigned long                   saved_line;
  48         ISC_LINK(struct inputsource)    link;
  49 } inputsource;
  50
  51 #define LEX_MAGIC                       ISC_MAGIC('L', 'e', 'x', '!')
  52 #define VALID_LEX(l)                    ISC_MAGIC_VALID(l, LEX_MAGIC)
  53
  54 struct isc_lex {
  55         /* Unlocked. */
  56         unsigned int                    magic;
  57         isc_mem_t *                     mctx;
  58         size_t                          max_token;
  59         char *                          data;
  60         unsigned int                    comments;
  61         isc_boolean_t                   comment_ok;
  62         isc_boolean_t                   last_was_eol;
  63         unsigned int                    paren_count;
  64         unsigned int                    saved_paren_count;
  65         isc_lexspecials_t               specials;
  66         LIST(struct inputsource)        sources;
  67 };
  68
  69 static inline isc_result_t
  70 grow_data(isc_lex_t *lex, size_t *remainingp, char **currp, char **prevp) {
  71         char *new;
  72
  73         new = isc_mem_get(lex->mctx, lex->max_token * 2 + 1);
  74         if (new == NULL)
  75                 return (ISC_R_NOMEMORY);
  76         memcpy(new, lex->data, lex->max_token + 1);
  77         *currp = new + (*currp - lex->data);
  78         if (*prevp != NULL)
  79                 *prevp = new + (*prevp - lex->data);
  80         isc_mem_put(lex->mctx, lex->data, lex->max_token + 1);
  81         lex->data = new;
  82         *remainingp += lex->max_token;
  83         lex->max_token *= 2;
  84         return (ISC_R_SUCCESS);
  85 }
  86
  87 isc_result_t
  88 isc_lex_create(isc_mem_t *mctx, size_t max_token, isc_lex_t **lexp) {
  89         isc_lex_t *lex;
  90
  91         /*
  92          * Create a lexer.
  93          */
  94
  95         REQUIRE(lexp != NULL && *lexp == NULL);
  96         REQUIRE(max_token > 0U);
  97
  98         lex = isc_mem_get(mctx, sizeof(*lex));
  99         if (lex == NULL)
 100                 return (ISC_R_NOMEMORY);
 101         lex->data = isc_mem_get(mctx, max_token + 1);
 102         if (lex->data == NULL) {
 103                 isc_mem_put(mctx, lex, sizeof(*lex));
 104                 return (ISC_R_NOMEMORY);
 105         }
 106         lex->mctx = mctx;
 107         lex->max_token = max_token;
 108         lex->comments = 0;
 109         lex->comment_ok = ISC_TRUE;
 110         lex->last_was_eol = ISC_TRUE;
 111         lex->paren_count = 0;
 112         lex->saved_paren_count = 0;
 113         memset(lex->specials, 0, 256);
 114         INIT_LIST(lex->sources);
 115         lex->magic = LEX_MAGIC;
 116
 117         *lexp = lex;
 118
 119         return (ISC_R_SUCCESS);
 120 }
 121
 122 void
 123 isc_lex_destroy(isc_lex_t **lexp) {
 124         isc_lex_t *lex;
 125
 126         /*
 127          * Destroy the lexer.
 128          */
 129
 130         REQUIRE(lexp != NULL);
 131         lex = *lexp;
 132         REQUIRE(VALID_LEX(lex));
 133
 134         while (!EMPTY(lex->sources))
 135                 RUNTIME_CHECK(isc_lex_close(lex) == ISC_R_SUCCESS);
 136         if (lex->data != NULL)
 137                 isc_mem_put(lex->mctx, lex->data, lex->max_token + 1);
 138         lex->magic = 0;
 139         isc_mem_put(lex->mctx, lex, sizeof(*lex));
 140
 141         *lexp = NULL;
 142 }
 143
 144 unsigned int
 145 isc_lex_getcomments(isc_lex_t *lex) {
 146         /*
 147          * Return the current lexer commenting styles.
 148          */
 149
 150         REQUIRE(VALID_LEX(lex));
 151
 152         return (lex->comments);
 153 }
 154
 155 void
 156 isc_lex_setcomments(isc_lex_t *lex, unsigned int comments) {
 157         /*
 158          * Set allowed lexer commenting styles.
 159          */
 160
 161         REQUIRE(VALID_LEX(lex));
 162
 163         lex->comments = comments;
 164 }
 165
 166 void
 167 isc_lex_getspecials(isc_lex_t *lex, isc_lexspecials_t specials) {
 168         /*
 169          * Put the current list of specials into 'specials'.
 170          */
 171
 172         REQUIRE(VALID_LEX(lex));
 173
 174         memcpy(specials, lex->specials, 256);
 175 }
 176
 177 void
 178 isc_lex_setspecials(isc_lex_t *lex, isc_lexspecials_t specials) {
 179         /*
 180          * The characters in 'specials' are returned as tokens.  Along with
 181          * whitespace, they delimit strings and numbers.
 182          */
 183
 184         REQUIRE(VALID_LEX(lex));
 185
 186         memcpy(lex->specials, specials, 256);
 187 }
 188
 189 static inline isc_result_t
 190 new_source(isc_lex_t *lex, isc_boolean_t is_file, isc_boolean_t need_close,
 191            void *input, const char *name)
 192 {
 193         inputsource *source;
 194         isc_result_t result;
 195
 196         source = isc_mem_get(lex->mctx, sizeof(*source));
 197         if (source == NULL)
 198                 return (ISC_R_NOMEMORY);
 199         source->result = ISC_R_SUCCESS;
 200         source->is_file = is_file;
 201         source->need_close = need_close;
 202         source->at_eof = ISC_FALSE;
 203         source->input = input;
 204         source->name = isc_mem_strdup(lex->mctx, name);
 205         if (source->name == NULL) {
 206                 isc_mem_put(lex->mctx, source, sizeof(*source));
 207                 return (ISC_R_NOMEMORY);
 208         }
 209         source->pushback = NULL;
 210         result = isc_buffer_allocate(lex->mctx, &source->pushback,
 211                                      lex->max_token);
 212         if (result != ISC_R_SUCCESS) {
 213                 isc_mem_free(lex->mctx, source->name);
 214                 isc_mem_put(lex->mctx, source, sizeof(*source));
 215                 return (result);
 216         }
 217         source->ignored = 0;
 218         source->line = 1;
 219         ISC_LIST_INITANDPREPEND(lex->sources, source, link);
 220
 221         return (ISC_R_SUCCESS);
 222 }
 223
 224 isc_result_t
 225 isc_lex_openfile(isc_lex_t *lex, const char *filename) {
 226         isc_result_t result;
 227         FILE *stream = NULL;
 228
 229         /*
 230          * Open 'filename' and make it the current input source for 'lex'.
 231          */
 232
 233         REQUIRE(VALID_LEX(lex));
 234
 235         result = isc_stdio_open(filename, "r", &stream);
 236         if (result != ISC_R_SUCCESS)
 237                 return (result);
 238
 239         result = new_source(lex, ISC_TRUE, ISC_TRUE, stream, filename);
 240         if (result != ISC_R_SUCCESS)
 241                 (void)fclose(stream);
 242         return (result);
 243 }
 244
 245 isc_result_t
 246 isc_lex_openstream(isc_lex_t *lex, FILE *stream) {
 247         char name[128];
 248
 249         /*
 250          * Make 'stream' the current input source for 'lex'.
 251          */
 252
 253         REQUIRE(VALID_LEX(lex));
 254
 255         snprintf(name, sizeof(name), "stream-%p", stream);
 256
 257         return (new_source(lex, ISC_TRUE, ISC_FALSE, stream, name));
 258 }
 259
 260 isc_result_t
 261 isc_lex_openbuffer(isc_lex_t *lex, isc_buffer_t *buffer) {
 262         char name[128];
 263
 264         /*
 265          * Make 'buffer' the current input source for 'lex'.
 266          */
 267
 268         REQUIRE(VALID_LEX(lex));
 269
 270         snprintf(name, sizeof(name), "buffer-%p", buffer);
 271
 272         return (new_source(lex, ISC_FALSE, ISC_FALSE, buffer, name));
 273 }
 274
 275 isc_result_t
 276 isc_lex_close(isc_lex_t *lex) {
 277         inputsource *source;
 278
 279         /*
 280          * Close the most recently opened object (i.e. file or buffer).
 281          */
 282
 283         REQUIRE(VALID_LEX(lex));
 284
 285         source = HEAD(lex->sources);
 286         if (source == NULL)
 287                 return (ISC_R_NOMORE);
 288
 289         ISC_LIST_UNLINK(lex->sources, source, link);
 290         if (source->is_file) {
 291                 if (source->need_close)
 292                         (void)fclose((FILE *)(source->input));
 293         }
 294         isc_mem_free(lex->mctx, source->name);
 295         isc_buffer_free(&source->pushback);
 296         isc_mem_put(lex->mctx, source, sizeof(*source));
 297
 298         return (ISC_R_SUCCESS);
 299 }
 300
 301 typedef enum {
 302         lexstate_start,
 303         lexstate_crlf,
 304         lexstate_string,
 305         lexstate_number,
 306         lexstate_maybecomment,
 307         lexstate_ccomment,
 308         lexstate_ccommentend,
 309         lexstate_eatline,
 310         lexstate_qstring
 311 } lexstate;
 312
 313 #define IWSEOL (ISC_LEXOPT_INITIALWS | ISC_LEXOPT_EOL)
 314
 315 static void
 316 pushback(inputsource *source, int c) {
 317         REQUIRE(source->pushback->current > 0);
 318         if (c == EOF) {
 319                 source->at_eof = ISC_FALSE;
 320                 return;
 321         }
 322         source->pushback->current--;
 323         if (c == '\n')
 324                 source->line--;
 325 }
 326
 327 static isc_result_t
 328 pushandgrow(isc_lex_t *lex, inputsource *source, int c) {
 329         if (isc_buffer_availablelength(source->pushback) == 0) {
 330                 isc_buffer_t *tbuf = NULL;
 331                 unsigned int oldlen;
 332                 isc_region_t used;
 333                 isc_result_t result;
 334
 335                 oldlen = isc_buffer_length(source->pushback);
 336                 result = isc_buffer_allocate(lex->mctx, &tbuf, oldlen * 2);
 337                 if (result != ISC_R_SUCCESS)
 338                         return (result);
 339                 isc_buffer_usedregion(source->pushback, &used);
 340                 result = isc_buffer_copyregion(tbuf, &used);
 341                 INSIST(result == ISC_R_SUCCESS);
 342                 tbuf->current = source->pushback->current;
 343                 isc_buffer_free(&source->pushback);
 344                 source->pushback = tbuf;
 345         }
 346         isc_buffer_putuint8(source->pushback, (isc_uint8_t)c);
 347         return (ISC_R_SUCCESS);
 348 }
 349
 350 isc_result_t
 351 isc_lex_gettoken(isc_lex_t *lex, unsigned int options, isc_token_t *tokenp) {
 352         inputsource *source;
 353         int c;
 354         isc_boolean_t done = ISC_FALSE;
 355         isc_boolean_t no_comments = ISC_FALSE;
 356         isc_boolean_t escaped = ISC_FALSE;
 357         lexstate state = lexstate_start;
 358         lexstate saved_state = lexstate_start;
 359         isc_buffer_t *buffer;
 360         FILE *stream;
 361         char *curr, *prev;
 362         size_t remaining;
 363         isc_uint32_t as_ulong;
 364         unsigned int saved_options;
 365         isc_result_t result;
 366
 367         /*
 368          * Get the next token.
 369          */
 370
 371         REQUIRE(VALID_LEX(lex));
 372         source = HEAD(lex->sources);
 373         REQUIRE(tokenp != NULL);
 374
 375         lex->saved_paren_count = lex->paren_count;
 376         source->saved_line = source->line;
 377
 378         if (source == NULL) {
 379                 if ((options & ISC_LEXOPT_NOMORE) != 0) {
 380                         tokenp->type = isc_tokentype_nomore;
 381                         return (ISC_R_SUCCESS);
 382                 }
 383                 return (ISC_R_NOMORE);
 384         }
 385
 386         if (source->result != ISC_R_SUCCESS)
 387                 return (source->result);
 388
 389         if (isc_buffer_remaininglength(source->pushback) == 0 &&
 390             source->at_eof)
 391         {
 392                 if ((options & ISC_LEXOPT_DNSMULTILINE) != 0 &&
 393                     lex->paren_count != 0) {
 394                         lex->paren_count = 0;
 395                         return (ISC_R_UNBALANCED);
 396                 }
 397                 if ((options & ISC_LEXOPT_EOF) != 0) {
 398                         tokenp->type = isc_tokentype_eof;
 399                         return (ISC_R_SUCCESS);
 400                 }
 401                 return (ISC_R_EOF);
 402         }
 403
 404         isc_buffer_compact(source->pushback);
 405
 406         saved_options = options;
 407         if ((options & ISC_LEXOPT_DNSMULTILINE) != 0 && lex->paren_count > 0)
 408                 options &= ~IWSEOL;
 409
 410         curr = lex->data;
 411         *curr = '\0';
 412
 413         prev = NULL;
 414         remaining = lex->max_token;
 415
 416 #ifdef HAVE_FLOCKFILE
 417         if (source->is_file)
 418                 flockfile(source->input);
 419 #endif
 420
 421         do {
 422                 if (isc_buffer_remaininglength(source->pushback) == 0) {
 423                         if (source->is_file) {
 424                                 stream = source->input;
 425
 426 #if defined(HAVE_FLOCKFILE) && defined(HAVE_GETCUNLOCKED)
 427                                 c = getc_unlocked(stream);
 428 #else
 429                                 c = getc(stream);
 430 #endif
 431                                 if (c == EOF) {
 432                                         if (ferror(stream)) {
 433                                                 source->result = ISC_R_IOERROR;
 434                                                 result = source->result;
 435                                                 goto done;
 436                                         }
 437                                         source->at_eof = ISC_TRUE;
 438                                 }
 439                         } else {
 440                                 buffer = source->input;
 441
 442                                 if (buffer->current == buffer->used) {
 443                                         c = EOF;
 444                                         source->at_eof = ISC_TRUE;
 445                                 } else {
 446                                         c = *((char *)buffer->base +
 447                                               buffer->current);
 448                                         buffer->current++;
 449                                 }
 450                         }
 451                         if (c != EOF) {
 452                                 source->result = pushandgrow(lex, source, c);
 453                                 if (source->result != ISC_R_SUCCESS) {
 454                                         result = source->result;
 455                                         goto done;
 456                                 }
 457                         }
 458                 }
 459
 460                 if (!source->at_eof) {
 461                         if (state == lexstate_start)
 462                                 /* Token has not started yet. */
 463                                 source->ignored =
 464                                    isc_buffer_consumedlength(source->pushback);
 465                         c = isc_buffer_getuint8(source->pushback);
 466                 } else {
 467                         c = EOF;
 468                 }
 469
 470                 if (c == '\n')
 471                         source->line++;
 472
 473                 if (lex->comment_ok && !no_comments) {
 474                         if (!escaped && c == ';' &&
 475                             ((lex->comments & ISC_LEXCOMMENT_DNSMASTERFILE)
 476                              != 0)) {
 477                                 saved_state = state;
 478                                 state = lexstate_eatline;
 479                                 no_comments = ISC_TRUE;
 480                                 continue;
 481                         } else if (c == '/' &&
 482                                    (lex->comments &
 483                                     (ISC_LEXCOMMENT_C|
 484                                      ISC_LEXCOMMENT_CPLUSPLUS)) != 0) {
 485                                 saved_state = state;
 486                                 state = lexstate_maybecomment;
 487                                 no_comments = ISC_TRUE;
 488                                 continue;
 489                         } else if (c == '#' &&
 490                                    ((lex->comments & ISC_LEXCOMMENT_SHELL)
 491                                     != 0)) {
 492                                 saved_state = state;
 493                                 state = lexstate_eatline;
 494                                 no_comments = ISC_TRUE;
 495                                 continue;
 496                         }
 497                 }
 498
 499         no_read:
 500                 /* INSIST(c == EOF || (c >= 0 && c <= 255)); */
 501                 switch (state) {
 502                 case lexstate_start:
 503                         if (c == EOF) {
 504                                 lex->last_was_eol = ISC_FALSE;
 505                                 if ((options & ISC_LEXOPT_DNSMULTILINE) != 0 &&
 506                                     lex->paren_count != 0) {
 507                                         lex->paren_count = 0;
 508                                         result = ISC_R_UNBALANCED;
 509                                         goto done;
 510                                 }
 511                                 if ((options & ISC_LEXOPT_EOF) == 0) {
 512                                         result = ISC_R_EOF;
 513                                         goto done;
 514                                 }
 515                                 tokenp->type = isc_tokentype_eof;
 516                                 done = ISC_TRUE;
 517                         } else if (c == ' ' || c == '\t') {
 518                                 if (lex->last_was_eol &&
 519                                     (options & ISC_LEXOPT_INITIALWS)
 520                                     != 0) {
 521                                         lex->last_was_eol = ISC_FALSE;
 522                                         tokenp->type = isc_tokentype_initialws;
 523                                         tokenp->value.as_char = c;
 524                                         done = ISC_TRUE;
 525                                 }
 526                         } else if (c == '\n') {
 527                                 if ((options & ISC_LEXOPT_EOL) != 0) {
 528                                         tokenp->type = isc_tokentype_eol;
 529                                         done = ISC_TRUE;
 530                                 }
 531                                 lex->last_was_eol = ISC_TRUE;
 532                         } else if (c == '\r') {
 533                                 if ((options & ISC_LEXOPT_EOL) != 0)
 534                                         state = lexstate_crlf;
 535                         } else if (c == '"' &&
 536                                    (options & ISC_LEXOPT_QSTRING) != 0) {
 537                                 lex->last_was_eol = ISC_FALSE;
 538                                 no_comments = ISC_TRUE;
 539                                 state = lexstate_qstring;
 540                         } else if (lex->specials[c]) {
 541                                 lex->last_was_eol = ISC_FALSE;
 542                                 if ((c == '(' || c == ')') &&
 543                                     (options & ISC_LEXOPT_DNSMULTILINE) != 0) {
 544                                         if (c == '(') {
 545                                                 if (lex->paren_count == 0)
 546                                                         options &= ~IWSEOL;
 547                                                 lex->paren_count++;
 548                                         } else {
 549                                                 if (lex->paren_count == 0) {
 550                                                     result = ISC_R_UNBALANCED;
 551                                                     goto done;
 552                                                 }
 553                                                 lex->paren_count--;
 554                                                 if (lex->paren_count == 0)
 555                                                         options =
 556                                                                 saved_options;
 557                                         }
 558                                         continue;
 559                                 }
 560                                 tokenp->type = isc_tokentype_special;
 561                                 tokenp->value.as_char = c;
 562                                 done = ISC_TRUE;
 563                         } else if (isdigit((unsigned char)c) &&
 564                                    (options & ISC_LEXOPT_NUMBER) != 0) {
 565                                 lex->last_was_eol = ISC_FALSE;
 566                                 state = lexstate_number;
 567                                 goto no_read;
 568                         } else {
 569                                 lex->last_was_eol = ISC_FALSE;
 570                                 state = lexstate_string;
 571                                 goto no_read;
 572                         }
 573                         break;
 574                 case lexstate_crlf:
 575                         if (c != '\n')
 576                                 pushback(source, c);
 577                         tokenp->type = isc_tokentype_eol;
 578                         done = ISC_TRUE;
 579                         lex->last_was_eol = ISC_TRUE;
 580                         break;
 581                 case lexstate_number:
 582                         if (c == EOF || !isdigit((unsigned char)c)) {
 583                                 if (c == ' ' || c == '\t' || c == '\r' ||
 584                                     c == '\n' || c == EOF ||
 585                                     lex->specials[c]) {
 586                                         int base;
 587                                         if ((options & ISC_LEXOPT_CNUMBER) != 0)
 588                                                 base = 0;
 589                                         else
 590                                                 base = 10;
 591                                         pushback(source, c);
 592
 593                                         result = isc_parse_uint32(&as_ulong,
 594                                                                   lex->data,
 595                                                                   base);
 596                                         if (result == ISC_R_SUCCESS) {
 597                                                 tokenp->type =
 598                                                         isc_tokentype_number;
 599                                                 tokenp->value.as_ulong =
 600                                                         as_ulong;
 601                                         } else if (result == ISC_R_BADNUMBER) {
 602                                                 isc_tokenvalue_t *v;
 603
 604                                                 tokenp->type =
 605                                                         isc_tokentype_string;
 606                                                 v = &(tokenp->value);
 607                                                 v->as_textregion.base =
 608                                                         lex->data;
 609                                                 v->as_textregion.length =
 610                                                         lex->max_token -
 611                                                         remaining;
 612                                         } else
 613                                                 goto done;
 614                                         done = ISC_TRUE;
 615                                         continue;
 616                                 } else if (!(options & ISC_LEXOPT_CNUMBER) ||
 617                                            ((c != 'x' && c != 'X') ||
 618                                            (curr != &lex->data[1]) ||
 619                                            (lex->data[0] != '0'))) {
 620                                         /* Above test supports hex numbers */
 621                                         state = lexstate_string;
 622                                 }
 623                         }
 624                         if (remaining == 0U) {
 625                                 result = grow_data(lex, &remaining,
 626                                                    &curr, &prev);
 627                                 if (result != ISC_R_SUCCESS)
 628                                         goto done;
 629                         }
 630                         INSIST(remaining > 0U);
 631                         *curr++ = c;
 632                         *curr = '\0';
 633                         remaining--;
 634                         break;
 635                 case lexstate_string:
 636                         if ((!escaped &&
 637                              (c == ' ' || c == '\t' || lex->specials[c])) ||
 638                             c == '\r' || c == '\n' || c == EOF) {
 639                                 pushback(source, c);
 640                                 if (source->result != ISC_R_SUCCESS) {
 641                                         result = source->result;
 642                                         goto done;
 643                                 }
 644                                 tokenp->type = isc_tokentype_string;
 645                                 tokenp->value.as_textregion.base = lex->data;
 646                                 tokenp->value.as_textregion.length =
 647                                         lex->max_token - remaining;
 648                                 done = ISC_TRUE;
 649                                 continue;
 650                         }
 651                         if ((options & ISC_LEXOPT_ESCAPE) != 0)
 652                                 escaped = (!escaped && c == '\\') ?
 653                                                 ISC_TRUE : ISC_FALSE;
 654                         if (remaining == 0U) {
 655                                 result = grow_data(lex, &remaining,
 656                                                    &curr, &prev);
 657                                 if (result != ISC_R_SUCCESS)
 658                                         goto done;
 659                         }
 660                         INSIST(remaining > 0U);
 661                         *curr++ = c;
 662                         *curr = '\0';
 663                         remaining--;
 664                         break;
 665                 case lexstate_maybecomment:
 666                         if (c == '*' &&
 667                             (lex->comments & ISC_LEXCOMMENT_C) != 0) {
 668                                 state = lexstate_ccomment;
 669                                 continue;
 670                         } else if (c == '/' &&
 671                             (lex->comments & ISC_LEXCOMMENT_CPLUSPLUS) != 0) {
 672                                 state = lexstate_eatline;
 673                                 continue;
 674                         }
 675                         pushback(source, c);
 676                         c = '/';
 677                         no_comments = ISC_FALSE;
 678                         state = saved_state;
 679                         goto no_read;
 680                 case lexstate_ccomment:
 681                         if (c == EOF) {
 682                                 result = ISC_R_UNEXPECTEDEND;
 683                                 goto done;
 684                         }
 685                         if (c == '*')
 686                                 state = lexstate_ccommentend;
 687                         break;
 688                 case lexstate_ccommentend:
 689                         if (c == EOF) {
 690                                 result = ISC_R_UNEXPECTEDEND;
 691                                 goto done;
 692                         }
 693                         if (c == '/') {
 694                                 /*
 695                                  * C-style comments become a single space.
 696                                  * We do this to ensure that a comment will
 697                                  * act as a delimiter for strings and
 698                                  * numbers.
 699                                  */
 700                                 c = ' ';
 701                                 no_comments = ISC_FALSE;
 702                                 state = saved_state;
 703                                 goto no_read;
 704                         } else if (c != '*')
 705                                 state = lexstate_ccomment;
 706                         break;
 707                 case lexstate_eatline:
 708                         if (c == EOF) {
 709                                 result = ISC_R_UNEXPECTEDEND;
 710                                 goto done;
 711                         }
 712                         if (c == '\n') {
 713                                 no_comments = ISC_FALSE;
 714                                 state = saved_state;
 715                                 goto no_read;
 716                         }
 717                         break;
 718                 case lexstate_qstring:
 719                         if (c == EOF) {
 720                                 result = ISC_R_UNEXPECTEDEND;
 721                                 goto done;
 722                         }
 723                         if (c == '"') {
 724                                 if (escaped) {
 725                                         escaped = ISC_FALSE;
 726                                         /*
 727                                          * Overwrite the preceding backslash.
 728                                          */
 729                                         INSIST(prev != NULL);
 730                                         *prev = '"';
 731                                 } else {
 732                                         tokenp->type = isc_tokentype_qstring;
 733                                         tokenp->value.as_textregion.base =
 734                                                 lex->data;
 735                                         tokenp->value.as_textregion.length =
 736                                                 lex->max_token - remaining;
 737                                         no_comments = ISC_FALSE;
 738                                         done = ISC_TRUE;
 739                                 }
 740                         } else {
 741                                 if (c == '\n' && !escaped &&
 742                             (options & ISC_LEXOPT_QSTRINGMULTILINE) == 0) {
 743                                         pushback(source, c);
 744                                         result = ISC_R_UNBALANCEDQUOTES;
 745                                         goto done;
 746                                 }
 747                                 if (c == '\\' && !escaped)
 748                                         escaped = ISC_TRUE;
 749                                 else
 750                                         escaped = ISC_FALSE;
 751                                 if (remaining == 0U) {
 752                                         result = grow_data(lex, &remaining,
 753                                                            &curr, &prev);
 754                                         if (result != ISC_R_SUCCESS)
 755                                                 goto done;
 756                                 }
 757                                 INSIST(remaining > 0U);
 758                                 prev = curr;
 759                                 *curr++ = c;
 760                                 *curr = '\0';
 761                                 remaining--;
 762                         }
 763                         break;
 764                 default:
 765                         FATAL_ERROR(__FILE__, __LINE__,
 766                                     isc_msgcat_get(isc_msgcat, ISC_MSGSET_LEX,
 767                                                    ISC_MSG_UNEXPECTEDSTATE,
 768                                                    "Unexpected state %d"),
 769                                     state);
 770                         /* Does not return. */
 771                 }
 772
 773         } while (!done);
 774
 775         result = ISC_R_SUCCESS;
 776  done:
 777 #ifdef HAVE_FLOCKFILE
 778         if (source->is_file)
 779                 funlockfile(source->input);
 780 #endif
 781         return (result);
 782 }
 783
 784 isc_result_t
 785 isc_lex_getmastertoken(isc_lex_t *lex, isc_token_t *token,
 786                        isc_tokentype_t expect, isc_boolean_t eol)
 787 {
 788         unsigned int options = ISC_LEXOPT_EOL | ISC_LEXOPT_EOF |
 789                                ISC_LEXOPT_DNSMULTILINE | ISC_LEXOPT_ESCAPE;
 790         isc_result_t result;
 791
 792         if (expect == isc_tokentype_qstring)
 793                 options |= ISC_LEXOPT_QSTRING;
 794         else if (expect == isc_tokentype_number)
 795                 options |= ISC_LEXOPT_NUMBER;
 796         result = isc_lex_gettoken(lex, options, token);
 797         if (result == ISC_R_RANGE)
 798                 isc_lex_ungettoken(lex, token);
 799         if (result != ISC_R_SUCCESS)
 800                 return (result);
 801
 802         if (eol && ((token->type == isc_tokentype_eol) ||
 803                     (token->type == isc_tokentype_eof)))
 804                 return (ISC_R_SUCCESS);
 805         if (token->type == isc_tokentype_string &&
 806             expect == isc_tokentype_qstring)
 807                 return (ISC_R_SUCCESS);
 808         if (token->type != expect) {
 809                 isc_lex_ungettoken(lex, token);
 810                 if (token->type == isc_tokentype_eol ||
 811                     token->type == isc_tokentype_eof)
 812                         return (ISC_R_UNEXPECTEDEND);
 813                 if (expect == isc_tokentype_number)
 814                         return (ISC_R_BADNUMBER);
 815                 return (ISC_R_UNEXPECTEDTOKEN);
 816         }
 817         return (ISC_R_SUCCESS);
 818 }
 819
 820 void
 821 isc_lex_ungettoken(isc_lex_t *lex, isc_token_t *tokenp) {
 822         inputsource *source;
 823         /*
 824          * Unget the current token.
 825          */
 826
 827         REQUIRE(VALID_LEX(lex));
 828         source = HEAD(lex->sources);
 829         REQUIRE(source != NULL);
 830         REQUIRE(tokenp != NULL);
 831         REQUIRE(isc_buffer_consumedlength(source->pushback) != 0 ||
 832                 tokenp->type == isc_tokentype_eof);
 833
 834         UNUSED(tokenp);
 835
 836         isc_buffer_first(source->pushback);
 837         lex->paren_count = lex->saved_paren_count;
 838         source->line = source->saved_line;
 839         source->at_eof = ISC_FALSE;
 840 }
 841
 842 void
 843 isc_lex_getlasttokentext(isc_lex_t *lex, isc_token_t *tokenp, isc_region_t *r)
 844 {
 845         inputsource *source;
 846
 847         REQUIRE(VALID_LEX(lex));
 848         source = HEAD(lex->sources);
 849         REQUIRE(source != NULL);
 850         REQUIRE(tokenp != NULL);
 851         REQUIRE(isc_buffer_consumedlength(source->pushback) != 0 ||
 852                 tokenp->type == isc_tokentype_eof);
 853
 854         UNUSED(tokenp);
 855
 856         INSIST(source->ignored <= isc_buffer_consumedlength(source->pushback));
 857         r->base = (unsigned char *)isc_buffer_base(source->pushback) +
 858                   source->ignored;
 859         r->length = isc_buffer_consumedlength(source->pushback) -
 860                     source->ignored;
 861 }
 862
 863
 864 char *
 865 isc_lex_getsourcename(isc_lex_t *lex) {
 866         inputsource *source;
 867
 868         REQUIRE(VALID_LEX(lex));
 869         source = HEAD(lex->sources);
 870
 871         if (source == NULL)
 872                 return (NULL);
 873
 874         return (source->name);
 875 }
 876
 877 unsigned long
 878 isc_lex_getsourceline(isc_lex_t *lex) {
 879         inputsource *source;
 880
 881         REQUIRE(VALID_LEX(lex));
 882         source = HEAD(lex->sources);
 883
 884         if (source == NULL)
 885                 return (0);
 886
 887         return (source->line);
 888 }
 889
 890
 891 isc_result_t
 892 isc_lex_setsourcename(isc_lex_t *lex, const char *name) {
 893         inputsource *source;
 894         char *newname;
 895
 896         REQUIRE(VALID_LEX(lex));
 897         source = HEAD(lex->sources);
 898
 899         if (source == NULL)
 900                 return(ISC_R_NOTFOUND);
 901         newname = isc_mem_strdup(lex->mctx, name);
 902         if (newname == NULL)
 903                 return (ISC_R_NOMEMORY);
 904         isc_mem_free(lex->mctx, source->name);
 905         source->name = newname;
 906         return (ISC_R_SUCCESS);
 907 }
 908
 909 isc_boolean_t
 910 isc_lex_isfile(isc_lex_t *lex) {
 911         inputsource *source;
 912
 913         REQUIRE(VALID_LEX(lex));
 914
 915         source = HEAD(lex->sources);
 916
 917         if (source == NULL)
 918                 return (ISC_FALSE);
 919
 920         return (source->is_file);
 921 }