1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719
|
/* Parse HyperText Document Address HTParse.c
** ================================
*/
#include "HTParse.h"
#define TRACE 0
#define FREE(x) if (x) {free(x); x = NULL;}
struct struct_parts
{
char *access;
char *host;
char *absolute;
char *relative;
/* char * search; no - treated as part of path */
char *anchor;
};
/* Strings of any length
** ---------------------
*/
PUBLIC int strcasecomp
ARGS2 (
CONST char *, a,
CONST char *, b)
{
CONST char *p = a;
CONST char *q = b;
for (p = a, q = b; *p && *q; p++, q++)
{
int diff = TOLOWER (*p) - TOLOWER (*q);
if (diff)
return diff;
}
if (*p)
return 1; /* p was longer than q */
if (*q)
return -1; /* p was shorter than q */
return 0; /* Exact match */
}
/* With count limit
** ----------------
*/
PUBLIC int strncasecomp
ARGS3 (
CONST char *, a,
CONST char *, b,
int, n)
{
CONST char *p = a;
CONST char *q = b;
for (p = a, q = b;;
p++, q++)
{
int diff;
if (p == (a + n))
return 0; /* Match up to n characters */
if (!(*p && *q))
return (*p - *q);
diff = TOLOWER (*p) - TOLOWER (*q);
if (diff)
return diff;
}
/*NOTREACHED */
}
/* Allocate a new copy of a string, and returns it
*/
PUBLIC char *HTSACopy
ARGS2 (
char **, dest,
CONST char *, src)
{
FREE (*dest);
if (src)
{
*dest = (char *) malloc (strlen (src) + 1);
if (*dest == NULL)
outofmem (__FILE__, "HTSACopy");
strcpy (*dest, src);
}
return *dest;
}
/* String Allocate and Concatenate
*/
PUBLIC char *HTSACat
ARGS2 (
char **, dest,
CONST char *, src)
{
if (src && *src)
{
if (*dest)
{
int length = strlen (*dest);
*dest = (char *) realloc (*dest, length + strlen (src) + 1);
if (*dest == NULL)
outofmem (__FILE__, "HTSACat");
strcpy (*dest + length, src);
}
else
{
*dest = (char *) malloc (strlen (src) + 1);
if (*dest == NULL)
outofmem (__FILE__, "HTSACat");
strcpy (*dest, src);
}
}
return *dest;
}
/* Strip white space off a string. HTStrip()
** -------------------------------
**
** On exit,
** Return value points to first non-white character, or to 0 if none.
** All trailing white space is OVERWRITTEN with zero.
*/
PUBLIC char *HTStrip
ARGS1 (
char *, s)
{
#define SPACE(c) ((c == ' ') || (c == '\t') || (c == '\n'))
char *p = s;
for (p = s; *p; p++)
; /* Find end of string */
for (p--; p >= s; p--)
{
if (SPACE (*p))
*p = '\0'; /* Zap trailing blanks */
else
break;
}
while (SPACE (*s))
s++; /* Strip leading blanks */
return s;
}
/* Scan a filename for its consituents. scan()
** ------------------------------------
**
** On entry,
** name points to a document name which may be incomplete.
** On exit,
** absolute or relative may be nonzero (but not both).
** host, anchor and access may be nonzero if they were specified.
** Any which are nonzero point to zero terminated strings.
*/
PRIVATE void scan
ARGS2 (
char *, name,
struct struct_parts *, parts)
{
char *after_access;
char *p;
/* int length = strlen (name); */
parts->access = NULL;
parts->host = NULL;
parts->absolute = NULL;
parts->relative = NULL;
parts->anchor = NULL;
/*
** Scan left-to-right for a scheme (access).
*/
after_access = name;
for (p = name; *p; p++)
{
if (*p == ':')
{
*p = '\0';
parts->access = name; /* Access name has been specified */
after_access = (p + 1);
break;
}
if (*p == '/' || *p == '#' || *p == ';' || *p == '?')
break;
}
#ifdef NOTDEFINED
for (p = (name + length - 1); p >= name; p--)
{
#endif /* NOTDEFINED */
/*
** Scan left-to-right for a fragment (anchor).
*/
for (p = after_access; *p; p++)
{
if (*p == '#')
{
parts->anchor = (p + 1);
*p = '\0'; /* terminate the rest */
}
}
/*
** Scan left-to-right for a host or absolute path.
*/
p = after_access;
if (*p == '/')
{
if (p[1] == '/')
{
parts->host = (p + 2); /* host has been specified */
*p = '\0'; /* Terminate access */
p = strchr (parts->host, '/'); /* look for end of host name if any */
if (p != NULL)
{
*p = '\0'; /* Terminate host */
parts->absolute = (p + 1); /* Root has been found */
}
}
else
{
parts->absolute = (p + 1); /* Root found but no host */
}
}
else
{
parts->relative = (*after_access) ?
after_access : NULL; /* NULL for "" */
}
/*
** Check schemes that commonly have unescaped hashes.
*/
if (parts->access && parts->anchor)
{
if ((!parts->host && strcasecomp (parts->access, "lynxcgi")) ||
!strcasecomp (parts->access, "nntp") ||
!strcasecomp (parts->access, "snews") ||
!strcasecomp (parts->access, "news") ||
!strcasecomp (parts->access, "data"))
{
/*
* Access specified but no host and not a lynxcgi URL, so the
* anchor may not really be one, e.g., news:j462#36487@foo.bar,
* or it's an nntp or snews URL, or news URL with a host.
* Restore the '#' in the address.
*/
*(parts->anchor - 1) = '#';
parts->anchor = NULL;
}
}
#ifdef NOT_DEFINED /* search is just treated as part of path */
{
char *p = (relative ? relative : absolute);
if (p != NULL)
{
char *q = strchr (p, '?'); /* Any search string? */
if (q != NULL)
{
*q = '\0'; /* If so, chop that off. */
parts->search = (q + 1);
}
}
}
#endif /* NOT_DEFINED */
} /*scan */
/* Parse a Name relative to another name. HTParse()
** --------------------------------------
**
** This returns those parts of a name which are given (and requested)
** substituting bits from the related name where necessary.
**
** On entry,
** aName A filename given
** relatedName A name relative to which aName is to be parsed
** wanted A mask for the bits which are wanted.
**
** On exit,
** returns A pointer to a malloc'd string which MUST BE FREED
*/
PUBLIC char *HTParse ARGS3 (
CONST char *, aName,
CONST char *, relatedName,
int, wanted)
{
char *result = NULL;
char *return_value = NULL;
int len;
char *name = NULL;
char *rel = NULL;
char *p;
char *access;
struct struct_parts given, related;
if (TRACE)
fprintf (stderr,
"HTParse: aName:%s relatedName:%s\n", aName, relatedName);
/*
** Allocate the output string.
*/
len = strlen (aName) + strlen (relatedName) + 10;
result = (char *) malloc (len); /* Lots of space: more than enough */
if (result == NULL)
outofmem (__FILE__, "HTParse");
result[0] = '\0'; /* Clear string */
/*
** Make working copies of the input strings to cut up.
*/
StrAllocCopy (name, aName);
StrAllocCopy (rel, relatedName);
/*
** Cut up the strings into URL fields.
*/
scan (name, &given);
scan (rel, &related);
/*
** Handle the scheme (access) field.
*/
if (given.access && given.host && !given.relative && !given.absolute)
{
if (!strcmp (given.access, "http") ||
!strcmp (given.access, "https") ||
!strcmp (given.access, "ftp"))
/*
** Assume root.
*/
given.absolute = "";
}
access = given.access ? given.access : related.access;
if (wanted & PARSE_ACCESS)
{
if (access)
{
strcat (result, access);
if (wanted & PARSE_PUNCTUATION)
strcat (result, ":");
}
}
/*
** If different schemes, inherit nothing.
**
** We'll try complying with RFC 1808 and
** the Fielding draft, and inherit nothing
** if both schemes are given, rather than
** only when they differ, except for
** file URLs - FM
**
** After trying it for a while, it's still
** premature, IHMO, to go along with it, so
** this is back to inheriting for identical
** schemes whether or not they are "file".
** If you want to try it again yourself,
** uncomment the strncasecomp() below. - FM
*/
if ((given.access && related.access) &&
( /* strcasecomp(given.access, "file") || */
strcmp (given.access, related.access)))
{
related.host = NULL;
related.absolute = NULL;
related.relative = NULL;
related.anchor = NULL;
}
/*
** Handle the host field.
*/
if (wanted & PARSE_HOST)
if (given.host || related.host)
{
char *tail = result + strlen (result);
if (wanted & PARSE_PUNCTUATION)
strcat (result, "//");
strcat (result, given.host ? given.host : related.host);
#define CLEAN_URLS
#ifdef CLEAN_URLS
/*
** Ignore default port numbers, and trailing dots on FQDNs,
** which will only cause identical addresses to look different.
*/
{
char *p, *h;
p = strchr (tail, ':');
if (p != NULL && !isdigit ((unsigned char) p[1]))
/*
** Colon not followed by a port number.
*/
*p = '\0';
if (p != NULL && p != '\0' && access != NULL)
{
/*
** Port specified.
*/
if ((!strcmp (access, "http") && !strcmp (p, ":80")) ||
(!strcmp (access, "gopher") && !strcmp (p, ":70")) ||
(!strcmp (access, "ftp") && !strcmp (p, ":21")) ||
(!strcmp (access, "wais") && !strcmp (p, ":210")) ||
(!strcmp (access, "nntp") && !strcmp (p, ":119")) ||
(!strcmp (access, "news") && !strcmp (p, ":119")) ||
(!strcmp (access, "snews") && !strcmp (p, ":563")) ||
(!strcmp (access, "finger") && !strcmp (p, ":79")) ||
(!strcmp (access, "cso") && !strcmp (p, ":105")))
*p = '\0'; /* It is the default: ignore it */
}
if (p == NULL)
{
int len = strlen (tail);
if (len > 0)
{
h = tail + len - 1; /* last char of hostname */
if (*h == '.')
*h = '\0'; /* chop final . */
}
}
else
{
h = p;
h--; /* End of hostname */
if (*h == '.')
{
/*
** Slide p over h.
*/
while (*p != '\0')
*h++ = *p++;
*h = '\0'; /* terminate */
}
}
}
#endif /* CLEAN_URLS */
}
/*
** If different hosts, inherit no path.
*/
if (given.host && related.host)
if (strcmp (given.host, related.host) != 0)
{
related.absolute = NULL;
related.relative = NULL;
related.anchor = NULL;
}
/*
** Handle the path.
*/
if (wanted & PARSE_PATH)
{
if (access && !given.absolute && given.relative)
{
if (!strcasecomp (access, "nntp") ||
!strcasecomp (access, "snews") ||
(!strcasecomp (access, "news") &&
!strncasecomp (result, "news://", 7)))
{
/*
* Treat all given nntp or snews paths,
* or given paths for news URLs with a host,
* as absolute.
*/
given.absolute = given.relative;
given.relative = NULL;
}
}
if (given.absolute)
{ /* All is given */
if (wanted & PARSE_PUNCTUATION)
strcat (result, "/");
strcat (result, given.absolute);
if (TRACE)
fprintf (stderr, "1\n");
}
else if (related.absolute)
{ /* Adopt path not name */
strcat (result, "/");
strcat (result, related.absolute);
if (given.relative)
{
p = strchr (result, '?'); /* Search part? */
if (p == NULL)
p = (result + strlen (result) - 1);
for (; *p != '/'; p--)
; /* last / */
p[1] = '\0'; /* Remove filename */
strcat (result, given.relative); /* Add given one */
HTSimplify (result);
}
if (TRACE)
fprintf (stderr, "2\n");
}
else if (given.relative)
{
strcat (result, given.relative); /* what we've got */
if (TRACE)
fprintf (stderr, "3\n");
}
else if (related.relative)
{
strcat (result, related.relative);
if (TRACE)
fprintf (stderr, "4\n");
}
else
{ /* No inheritance */
if (strncasecomp (aName, "lynxcgi:", 8) &&
strncasecomp (aName, "lynxexec:", 9) &&
strncasecomp (aName, "lynxprog:", 9))
{
strcat (result, "/");
}
if (!strcmp (result, "news:/"))
result[5] = '*';
if (TRACE)
fprintf (stderr, "5\n");
}
}
/*
** Handle the fragment (anchor).
*/
if (wanted & PARSE_ANCHOR)
if ((given.anchor && *given.anchor) ||
(!given.anchor && related.anchor))
{
if (wanted & PARSE_PUNCTUATION)
strcat (result, "#");
strcat (result, (given.anchor) ?
given.anchor : related.anchor);
}
if (TRACE)
fprintf (stderr, "HTParse: result:%s\n", result);
FREE (rel);
FREE (name);
StrAllocCopy (return_value, result);
FREE (result);
return return_value; /* exactly the right length */
}
/* Simplify a filename. HTSimplify()
** --------------------
**
** A unix-style file is allowed to contain the seqeunce xxx/../ which may
** be replaced by "" , and the seqeunce "/./" which may be replaced by "/".
** Simplification helps us recognize duplicate filenames.
**
** Thus, /etc/junk/../fred becomes /etc/fred
** /etc/junk/./fred becomes /etc/junk/fred
**
** but we should NOT change
** http://fred.xxx.edu/../..
**
** or ../../albert.html
*/
PUBLIC void HTSimplify ARGS1 (
char *, filename)
{
char *p;
char *q, *q1;
if (filename == NULL)
return;
if ((filename[0] && filename[1]) && strchr (filename, '/') != NULL)
{
for (p = (filename + 2); *p; p++)
{
if (*p == '/')
{
if ((p[1] == '.') && (p[2] == '.') &&
(p[3] == '/' || p[3] == '\0'))
{
/*
** Handle "/../" or "/..".
*/
for (q = (p - 1); (q >= filename) && (*q != '/'); q--)
/*
** Back up to previous slash or beginning of string.
*/
;
if ((q[0] == '/') && strncmp (q, "/../", 4) &&
!((q - 1) > filename && q[-1] == '/'))
{
/*
** Not at beginning of string or in a
** host field, so remove the "/xxx/..".
*/
q1 = (p + 3);
p = q;
while (*q1 != '\0')
*p++ = *q1++;
*p = '\0'; /* terminate */
#ifdef NOTDEFINED
/*
** Make sure filename has at least one slash.
*/
if (*filename == '\0')
{
*filename = '/';
*(filename + 1) = '\0';
}
#endif /* NOTDEFINED */
/*
** Start again with previous slash.
*/
p = (q - 1);
}
}
else if (p[1] == '.' && p[2] == '/')
{
/*
** Handle "./" by removing the characters.
*/
q = p;
q1 = (p + 2);
while (*q1 != '\0')
*q++ = *q1++;
*q = '\0'; /* terminate */
p--;
}
else if (p[1] == '.' && p[2] == '\0')
{
/*
** Handle terminal "." by removing the character.
*/
p[1] = '\0';
}
}
}
}
}
/* Make Relative Name. HTRelative()
** -------------------
**
** This function creates and returns a string which gives an expression of
** one address as related to another. Where there is no relation, an absolute
** address is retured.
**
** On entry,
** Both names must be absolute, fully qualified names of nodes
** (no anchor bits)
**
** On exit,
** The return result points to a newly allocated name which, if
** parsed by HTParse relative to relatedName, will yield aName.
** The caller is responsible for freeing the resulting name later.
**
*/
PUBLIC char *HTRelative ARGS2 (
CONST char *, aName,
CONST char *, relatedName)
{
char *result = NULL;
CONST char *p = aName;
CONST char *q = relatedName;
CONST char *after_access = NULL;
CONST char *path = NULL;
CONST char *last_slash = NULL;
int slashes = 0;
for (; *p; p++, q++)
{ /* Find extent of match */
if (*p != *q)
break;
if (*p == ':')
after_access = p + 1;
if (*p == '/')
{
last_slash = p;
slashes++;
if (slashes == 3)
path = p;
}
}
/* q, p point to the first non-matching character or zero */
if (!after_access)
{ /* Different access */
StrAllocCopy (result, aName);
}
else if (slashes < 3)
{ /* Different nodes */
StrAllocCopy (result, after_access);
}
else if (slashes == 3)
{ /* Same node, different path */
StrAllocCopy (result, path);
}
else
{ /* Some path in common */
int levels = 0;
for (; *q && (*q != '#'); q++)
if (*q == '/')
levels++;
result = (char *) malloc (3 * levels + strlen (last_slash) + 1);
if (result == NULL)
outofmem (__FILE__, "HTRelative");
result[0] = '\0';
for (; levels; levels--)
strcat (result, "../");
strcat (result, last_slash + 1);
}
if (TRACE)
fprintf (stderr, "HT: `%s' expressed relative to\n `%s' is\n `%s'.",
aName, relatedName, result);
return result;
}
|