/* HTML parser for Wget.
- Copyright (C) 1998, 2000 Free Software Foundation, Inc.
+ Copyright (C) 1998, 2000, 2003 Free Software Foundation, Inc.
-This file is part of Wget.
+This file is part of GNU Wget.
-This program is free software; you can redistribute it and/or modify
+GNU Wget is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.
-This program is distributed in the hope that it will be useful,
+GNU Wget is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+along with Wget; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+In addition, as a special exception, the Free Software Foundation
+gives permission to link the code of its release of Wget with the
+OpenSSL project's "OpenSSL" library (or with modified versions of it
+that use the same license as the "OpenSSL" library), and distribute
+the linked executables. You must obey the GNU General Public License
+in all respects for all of the code used other than "OpenSSL". If you
+modify this file, you may extend this exception to your version of the
+file, but you are not obligated to do so. If you do not wish to do
+so, delete this exception statement from your version. */
/* The only entry point to this module is map_html_tags(), which see. */
as a backend for one.
Due to time and other constraints, this parser was not integrated
- into Wget until the version ???. */
+ into Wget until the version 1.7. */
/* DESCRIPTION:
#include <config.h>
+#ifdef STANDALONE
+# define I_REALLY_WANT_CTYPE_MACROS
+#endif
+
#include <stdio.h>
#include <stdlib.h>
-#include <ctype.h>
#ifdef HAVE_STRING_H
# include <string.h>
#else
# define xmalloc malloc
# define xrealloc realloc
# define xfree free
+
+# define ISSPACE(x) isspace (x)
+# define ISDIGIT(x) isdigit (x)
+# define ISALPHA(x) isalpha (x)
+# define ISALNUM(x) isalnum (x)
+# define TOLOWER(x) tolower (x)
#endif /* STANDALONE */
-/* Pool support. For efficiency, map_html_tags() stores temporary
- string data to a single stack-allocated pool. If the pool proves
- too small, additional memory is allocated/resized with
- malloc()/realloc(). */
+/* Pool support. A pool is a resizable chunk of memory. It is first
+ allocated on the stack, and moved to the heap if it needs to be
+ larger than originally expected. map_html_tags() uses it to store
+ the zero-terminated names and values of tags and attributes.
+
+ Thus taginfo->name, and attr->name and attr->value for each
+ attribute, do not point into separately allocated areas, but into
+ different parts of the pool, separated only by terminating zeros.
+ This ensures minimum amount of allocation and, for most tags, no
+ allocation because the entire pool is kept on the stack. */
struct pool {
char *contents; /* pointer to the contents. */
return 1;
}
\f
-/* RFC1866: name [of attribute or tag] consists of letters, digits,
- periods, or hyphens. We also allow _, for compatibility with
- brain-damaged generators. */
-#define NAME_CHAR_P(x) (ISALNUM (x) || (x) == '.' || (x) == '-' || (x) == '_')
-
-/* States while advancing through comments. */
-#define AC_S_DONE 0
-#define AC_S_BACKOUT 1
-#define AC_S_BANG 2
-#define AC_S_DEFAULT 3
-#define AC_S_DCLNAME 4
-#define AC_S_DASH1 5
-#define AC_S_DASH2 6
-#define AC_S_COMMENT 7
-#define AC_S_DASH3 8
-#define AC_S_DASH4 9
-#define AC_S_QUOTE1 10
-#define AC_S_IN_QUOTE 11
-#define AC_S_QUOTE2 12
+/* Originally we used to adhere to rfc 1866 here, and allowed only
+ letters, digits, periods, and hyphens as names (of tags or
+ attributes). However, this broke too many pages which used
+ proprietary or strange attributes, e.g. <img src="a.gif"
+ v:shapes="whatever">.
+
+ So now we allow any character except:
+ * whitespace
+ * 8-bit and control chars
+ * characters that clearly cannot be part of name:
+ '=', '>', '/'.
+
+ This only affects attribute and tag names; attribute values allow
+ an even greater variety of characters. */
+
+#define NAME_CHAR_P(x) ((x) > 32 && (x) < 127 \
+ && (x) != '=' && (x) != '>' && (x) != '/')
#ifdef STANDALONE
static int comment_backout_count;
#endif
-/* Advance over an SGML declaration (the <!...> forms you find in HTML
- documents). The function returns the location after the
- declaration. The reason we need this is that HTML comments are
- expressed as comments in so-called "empty declarations".
+/* Advance over an SGML declaration, such as <!DOCTYPE ...>. In
+ strict comments mode, this is used for skipping over comments as
+ well.
To recap: any SGML declaration may have comments associated with
it, e.g.
<!-- have -- -- fun -->
Whitespace is allowed between and after the comments, but not
- before the first comment.
+ before the first comment. Additionally, this function attempts to
+ handle double quotes in SGML declarations correctly. */
- Additionally, this function attempts to handle double quotes in
- SGML declarations correctly. */
static const char *
advance_declaration (const char *beg, const char *end)
{
const char *p = beg;
char quote_char = '\0'; /* shut up, gcc! */
char ch;
- int state = AC_S_BANG;
+
+ enum {
+ AC_S_DONE,
+ AC_S_BACKOUT,
+ AC_S_BANG,
+ AC_S_DEFAULT,
+ AC_S_DCLNAME,
+ AC_S_DASH1,
+ AC_S_DASH2,
+ AC_S_COMMENT,
+ AC_S_DASH3,
+ AC_S_DASH4,
+ AC_S_QUOTE1,
+ AC_S_IN_QUOTE,
+ AC_S_QUOTE2,
+ } state = AC_S_BANG;
if (beg == end)
return beg;
}
break;
case AC_S_DCLNAME:
- if (NAME_CHAR_P (ch))
- ch = *p++;
- else if (ch == '-')
+ if (ch == '-')
state = AC_S_DASH1;
+ else if (NAME_CHAR_P (ch))
+ ch = *p++;
else
state = AC_S_DEFAULT;
break;
case AC_S_QUOTE1:
- assert (ch == '\'' || ch == '"');
+ /* We must use 0x22 because broken assert macros choke on
+ '"' and '\"'. */
+ assert (ch == '\'' || ch == 0x22);
quote_char = ch; /* cheating -- I really don't feel like
introducing more different states for
different quote characters. */
}
return p;
}
+
+/* Find the first occurrence of the substring "-->" in [BEG, END) and
+ return the pointer to the character after the substring. If the
+ substring is not found, return NULL. */
+
+static const char *
+find_comment_end (const char *beg, const char *end)
+{
+ /* Open-coded Boyer-Moore search for "-->". Examine the third char;
+ if it's not '>' or '-', advance by three characters. Otherwise,
+ look at the preceding characters and try to find a match. */
+
+ const char *p = beg - 1;
+
+ while ((p += 3) < end)
+ switch (p[0])
+ {
+ case '>':
+ if (p[-1] == '-' && p[-2] == '-')
+ return p + 1;
+ break;
+ case '-':
+ at_dash:
+ if (p[-1] == '-')
+ {
+ at_dash_dash:
+ if (++p == end) return NULL;
+ switch (p[0])
+ {
+ case '>': return p + 1;
+ case '-': goto at_dash_dash;
+ }
+ }
+ else
+ {
+ if ((p += 2) >= end) return NULL;
+ switch (p[0])
+ {
+ case '>':
+ if (p[-1] == '-')
+ return p + 1;
+ break;
+ case '-':
+ goto at_dash;
+ }
+ }
+ }
+ return NULL;
+}
\f
/* Advance P (a char pointer), with the explicit intent of being able
to read the next character. If this is not possible, go to finish. */
declaration). */
if (*p == '!')
{
- /* This is an SGML declaration -- just skip it. */
- p = advance_declaration (p, end);
+ if (!opt.strict_comments
+ && p < end + 3 && p[1] == '-' && p[2] == '-')
+ {
+ /* If strict comments are not enforced and if we know
+ we're looking at a comment, simply look for the
+ terminating "-->". Non-strict is the default because
+ it works in other browsers and most HTML writers can't
+ be bothered with getting the comments right. */
+ const char *comment_end = find_comment_end (p + 3, end);
+ if (comment_end)
+ p = comment_end;
+ }
+ else
+ {
+ /* Either in strict comment mode or looking at a non-empty
+ declaration. Real declarations are much less likely to
+ be misused the way comments are, so advance over them
+ properly regardless of strictness. */
+ p = advance_declaration (p, end);
+ }
if (p == end)
goto finish;
goto look_for_tag;
SKIP_WS (p);
+ if (*p == '/')
+ {
+ /* A slash at this point means the tag is about to be
+ closed. This is legal in XML and has been popularized
+ in HTML via XHTML. */
+ /* <foo a=b c=d /> */
+ /* ^ */
+ ADVANCE (p);
+ SKIP_WS (p);
+ if (*p != '>')
+ goto backout_tag;
+ }
+
/* Check for end of tag definition. */
if (*p == '>')
break;
/* Establish bounds of attribute value. */
SKIP_WS (p);
- if (NAME_CHAR_P (*p) || *p == '>')
+ if (NAME_CHAR_P (*p) || *p == '/' || *p == '>')
{
/* Minimized attribute syntax allows `=' to be omitted.
For example, <UL COMPACT> is a valid shorthand for <UL
/* We skipped the whitespace and found something that is
neither `=' nor the beginning of the next attribute's
name. Back out. */
- goto backout_tag; /* <foo bar /... */
+ goto backout_tag; /* <foo bar [... */
/* ^ */
}
projects / wget / blobdiff