1 /*****************************************************************************
2 * xlist.c : a trivial parser for XML-like tags
3 *****************************************************************************
4 * Copyright (C) 2003-2004 Commonwealth Scientific and Industrial Research
5 * Organisation (CSIRO) Australia
6 * Copyright (C) 2000-2004 the VideoLAN team
10 * Authors: Conrad Parker <Conrad.Parker@csiro.au>
11 * Andre Pang <Andre.Pang@csiro.au>
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
26 *****************************************************************************/
31 #include <vlc_common.h>
46 #define MIN(a,b) ((a)<(b)?(a):(b))
49 #define MAX(a,b) ((a)>(b)?(a):(b))
51 typedef struct _XTag XTag;
52 typedef struct _XAttribute XAttribute;
53 typedef struct _XTagParser XTagParser;
56 * struct _XTag is kind of a union ... it normally represents a whole
57 * tag (and its children), but it could alternatively represent some
58 * PCDATA. Basically, if tag->pcdata is non-NULL, interpret only it and
59 * ignore the name, attributes and inner_tags.
67 XList * current_child;
76 int valid; /* boolean */
82 void xtag_free (XTag * xtag);
83 XTag * xtag_new_parse (const char * s, int n);
84 char * xtag_get_name (XTag * xtag);
85 char * xtag_get_pcdata (XTag * xtag);
86 char * xtag_get_attribute (XTag * xtag, const char* attribute);
87 XTag * xtag_first_child (XTag * xtag, const char * name);
88 XTag * xtag_next_child (XTag * xtag, char * name);
89 int xtag_snprint (char * buf, int n, XTag * xtag);
91 /* Character classes */
93 #define X_WHITESPACE 1<<0
94 #define X_OPENTAG 1<<1
95 #define X_CLOSETAG 1<<2
102 xtag_cin (char c, int char_class)
104 if (char_class & X_WHITESPACE)
105 if (isspace(c)) return true;
107 if (char_class & X_OPENTAG)
108 if (c == '<') return true;
110 if (char_class & X_CLOSETAG)
111 if (c == '>') return true;
113 if (char_class & X_DQUOTE)
114 if (c == '"') return true;
116 if (char_class & X_SQUOTE)
117 if (c == '\'') return true;
119 if (char_class & X_EQUAL)
120 if (c == '=') return true;
122 if (char_class & X_SLASH)
123 if (c == '/') return true;
129 xtag_index (XTagParser * parser, int char_class)
136 for (i = 0; s[i] && s != parser->end; i++) {
137 if (xtag_cin(s[i], char_class)) return i;
144 xtag_skip_over (XTagParser * parser, int char_class)
149 if (!parser->valid) return;
151 s = (char *)parser->start;
153 for (i = 0; s[i] && s != parser->end; i++) {
154 if (!xtag_cin(s[i], char_class)) {
155 parser->start = &s[i];
164 xtag_skip_whitespace (XTagParser * parser)
166 xtag_skip_over (parser, X_WHITESPACE);
171 xtag_skip_to (XTagParser * parser, int char_class)
176 if (!parser->valid) return;
178 s = (char *)parser->start;
180 for (i = 0; s[i] && s != parser->end; i++) {
181 if (xtag_cin(s[i], char_class)) {
182 parser->start = &s[i];
192 xtag_slurp_to (XTagParser * parser, int good_end, int bad_end)
197 if (!parser->valid) return NULL;
201 xi = xtag_index (parser, good_end | bad_end);
203 if (xi > 0 && xtag_cin (s[xi], good_end)) {
205 strncpy (ret, s, xi);
207 parser->start = &s[xi];
215 xtag_assert_and_pass (XTagParser * parser, int char_class)
219 if (!parser->valid) return false;
223 if (!xtag_cin (s[0], char_class)) {
224 parser->valid = false;
228 parser->start = &s[1];
234 xtag_slurp_quoted (XTagParser * parser)
237 int quote = X_DQUOTE; /* quote char to match on */
240 if (!parser->valid) return NULL;
242 xtag_skip_whitespace (parser);
246 if (xtag_cin (s[0], X_SQUOTE)) quote = X_SQUOTE;
248 if (!xtag_assert_and_pass (parser, quote)) return NULL;
252 for (xi = 0; s[xi]; xi++) {
253 if (xtag_cin (s[xi], quote)) {
254 if (!(xi > 1 && s[xi-1] == '\\')) break;
259 strncpy (ret, s, xi);
261 parser->start = &s[xi];
263 if (!xtag_assert_and_pass (parser, quote))
273 xtag_parse_attribute (XTagParser * parser)
276 char * name, * value;
279 if (!parser->valid) return NULL;
281 xtag_skip_whitespace (parser);
283 name = xtag_slurp_to (parser, X_WHITESPACE | X_EQUAL, X_SLASH | X_CLOSETAG);
285 if (name == NULL) return NULL;
287 xtag_skip_whitespace (parser);
290 if (!xtag_assert_and_pass (parser, X_EQUAL)) {
292 printf ("xtag: attr failed EQUAL on <%s>\n", name);
297 xtag_skip_whitespace (parser);
299 value = xtag_slurp_quoted (parser);
303 printf ("Got NULL quoted attribute value\n");
308 attr = malloc (sizeof (*attr));
317 parser->valid = false;
323 xtag_parse_tag (XTagParser * parser)
331 if (!parser->valid) return NULL;
333 if ((pcdata = xtag_slurp_to (parser, X_OPENTAG, X_NONE)) != NULL) {
334 tag = malloc (sizeof (*tag));
336 tag->pcdata = pcdata;
337 tag->parent = parser->current_tag;
338 tag->attributes = NULL;
339 tag->children = NULL;
340 tag->current_child = NULL;
347 /* if this starts a close tag, return NULL and let the parent take it */
348 if (xtag_cin (s[0], X_OPENTAG) && xtag_cin (s[1], X_SLASH))
351 if (!xtag_assert_and_pass (parser, X_OPENTAG)) return NULL;
353 name = xtag_slurp_to (parser, X_WHITESPACE | X_SLASH | X_CLOSETAG, X_NONE);
355 if (name == NULL) return NULL;
358 printf ("<%s ...\n", name);
361 tag = malloc (sizeof (*tag));
364 tag->parent = parser->current_tag;
365 tag->attributes = NULL;
366 tag->children = NULL;
367 tag->current_child = NULL;
371 if (xtag_cin (s[0], X_WHITESPACE)) {
372 while ((attr = xtag_parse_attribute (parser)) != NULL) {
373 tag->attributes = xlist_append (tag->attributes, attr);
377 xtag_skip_whitespace (parser);
381 if (xtag_cin (s[0], X_CLOSETAG)) {
382 parser->current_tag = tag;
384 xtag_assert_and_pass (parser, X_CLOSETAG);
386 while ((inner = xtag_parse_tag (parser)) != NULL) {
387 tag->children = xlist_append (tag->children, inner);
390 xtag_skip_whitespace (parser);
392 xtag_assert_and_pass (parser, X_OPENTAG);
393 xtag_assert_and_pass (parser, X_SLASH);
394 name = xtag_slurp_to (parser, X_WHITESPACE | X_CLOSETAG, X_NONE);
396 if (name && tag->name && strcmp (name, tag->name)) {
398 printf ("got %s expected %s\n", name, tag->name);
400 parser->valid = false;
405 xtag_skip_whitespace (parser);
406 xtag_assert_and_pass (parser, X_CLOSETAG);
409 xtag_assert_and_pass (parser, X_SLASH);
410 xtag_assert_and_pass (parser, X_CLOSETAG);
417 void xtag_free (XTag * xtag)
427 free( xtag->pcdata );
429 for( l = xtag->attributes; l; l = l->next) {
430 if((attr = (XAttribute *)l->data) != NULL) {
436 xlist_free (xtag->attributes);
438 for (l = xtag->children; l; l = l->next) {
439 child = (XTag *)l->data;
442 xlist_free (xtag->children);
448 xtag_new_parse (const char * s, int n)
451 XTag * tag, * ttag, * wrapper;
454 parser.current_tag = NULL;
455 parser.start = (char *)s;
462 parser.end = (char *)&s[n];
464 tag = xtag_parse_tag (&parser);
471 if ((ttag = xtag_parse_tag (&parser)) != NULL) {
478 wrapper = malloc (sizeof (XTag));
479 wrapper->name = NULL;
480 wrapper->pcdata = NULL;
481 wrapper->parent = NULL;
482 wrapper->attributes = NULL;
483 wrapper->children = NULL;
484 wrapper->current_child = NULL;
486 wrapper->children = xlist_append (wrapper->children, tag);
487 wrapper->children = xlist_append (wrapper->children, ttag);
489 while ((ttag = xtag_parse_tag (&parser)) != NULL) {
496 wrapper->children = xlist_append (wrapper->children, ttag);
505 xtag_get_name (XTag * xtag)
507 return xtag ? xtag->name : NULL;
511 xtag_get_pcdata (XTag * xtag)
516 if (xtag == NULL) return NULL;
518 for (l = xtag->children; l; l = l->next) {
519 child = (XTag *)l->data;
520 if (child->pcdata != NULL) {
521 return child->pcdata;
528 char* xtag_get_attribute (XTag * xtag, const char * attribute)
536 for( l = xtag->attributes; l; l = l->next )
538 if( ( attr = (XAttribute *)l->data ) != NULL )
540 if( attr->name && attribute && !strcmp( attr->name, attribute ) )
547 XTag* xtag_first_child (XTag * xtag, const char * name)
555 if( ( l = xtag->children ) == NULL )
560 xtag->current_child = l;
561 return (XTag *)l->data;
564 for( ; l; l = l->next )
566 child = (XTag *)l->data;
568 if( child->name && name && !strcmp( child->name, name ) )
570 xtag->current_child = l;
575 xtag->current_child = NULL;
580 xtag_next_child (XTag * xtag, char * name)
585 if (xtag == NULL) return NULL;
587 if ((l = xtag->current_child) == NULL)
588 return xtag_first_child (xtag, name);
590 if ((l = l->next) == NULL)
594 xtag->current_child = l;
595 return (XTag *)l->data;
598 for (; l; l = l->next) {
599 child = (XTag *)l->data;
601 if (child->name && name && !strcmp(child->name, name)) {
602 xtag->current_child = l;
607 xtag->current_child = NULL;
613 * This snprints function takes a variable list of char *, the last of
614 * which must be NULL, and prints each in turn to buf.
615 * Returns C99-style total length that would have been written, even if
616 * this is larger than n.
619 xtag_snprints (char * buf, int n, ...)
623 int len, to_copy, total = 0;
627 for (s = va_arg (ap, char *); s; s = va_arg (ap, char *)) {
630 if ((to_copy = MIN (n, len)) > 0) {
631 memcpy (buf, s, to_copy);
645 xtag_snprint (char * buf, int n, XTag * xtag)
658 if (n > 0) buf[0] = '\0';
663 nn = xtag_snprints (buf, n, xtag->pcdata, NULL);
670 nn = xtag_snprints (buf, n, "<", xtag->name, NULL);
673 for (l = xtag->attributes; l; l = l->next) {
674 attr = (XAttribute *)l->data;
676 nn = xtag_snprints (buf, n, " ", attr->name, "=\"", attr->value, "\"",
681 if (xtag->children == NULL) {
682 nn = xtag_snprints (buf, n, "/>", NULL);
688 nn = xtag_snprints (buf, n, ">", NULL);
692 for (l = xtag->children; l; l = l->next) {
693 child = (XTag *)l->data;
695 nn = xtag_snprint (buf, n, child);
700 nn = xtag_snprints (buf, n, "</", xtag->name, ">", NULL);