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|
<head>
<title>html(3) - Plan 9 from User Space</title>
<meta content="text/html; charset=utf-8" http-equiv=Content-Type>
</head>
<body bgcolor=#ffffff>
<table border=0 cellpadding=0 cellspacing=0 width=100%>
<tr height=10><td>
<tr><td width=20><td>
<tr><td width=20><td><b>HTML(3)</b><td align=right><b>HTML(3)</b>
<tr><td width=20><td colspan=2>
<br>
<p><font size=+1><b>NAME </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
parsehtml, printitems, validitems, freeitems, freedocinfo, dimenkind,
dimenspec, targetid, targetname, fromStr, toStr – HTML parser<br>
</table>
<p><font size=+1><b>SYNOPSIS </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
<tt><font size=+1>#include <u.h><br>
#include <libc.h><br>
#include <html.h><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Item* parsehtml(uchar* data, int datalen, Rune* src, int mtype,<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
int chset, Docinfo** pdi)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</table>
</table>
</font></tt>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
</table>
</table>
<tt><font size=+1>void printitems(Item* items, char* msg)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>int validitems(Item* items)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>void freeitems(Item* items)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>void freedocinfo(Docinfo* d)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>int dimenkind(Dimen d)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>int dimenspec(Dimen d)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>int targetid(Rune* s)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Rune* targetname(int targid)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>uchar* fromStr(Rune* buf, int n, int chset)<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Rune* toStr(uchar* buf, int n, int chset)<br>
</font></tt>
</table>
<p><font size=+1><b>DESCRIPTION </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
This library implements a parser for HTML 4.0 documents. The parsed
HTML is converted into an intermediate representation that describes
how the formatted HTML should be laid out.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Parsehtml</i> parses an entire HTML document contained in the buffer
<i>data</i> and having length <i>datalen</i>. The URL of the document should
be passed in as <i>src</i>. <i>Mtype</i> is the media type of the document,
which should be either <tt><font size=+1>TextHtml</font></tt> or <tt><font size=+1>TextPlain</font></tt>. The character set
of the document is described in <i>chset</i>, which can be
one of <tt><font size=+1>US_Ascii</font></tt>, <tt><font size=+1>ISO_8859_1</font></tt>, <tt><font size=+1>UTF_8</font></tt> or <tt><font size=+1>Unicode</font></tt>. The return value
is a linked list of <tt><font size=+1>Item</font></tt> structures, described in detail below.
As a side effect, <tt><font size=+1>*</font></tt><i>pdi</i> is set to point to a newly created <tt><font size=+1>Docinfo</font></tt>
structure, containing information pertaining to the entire document.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The library expects two allocation routines to be provided by
the caller, <tt><font size=+1>emalloc</font></tt> and <tt><font size=+1>erealloc</font></tt>. These routines are analogous
to the standard malloc and realloc routines, except that they
should not return if the memory allocation fails. In addition,
<tt><font size=+1>emalloc</font></tt> is required to zero the memory.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
For debugging purposes, <i>printitems</i> may be called to display the
contents of an item list; individual items may be printed using
the <tt><font size=+1>%I</font></tt> print verb, installed on the first call to <i>parsehtml</i>. <i>validitems</i>
traverses the item list, checking that all of the pointers are
valid. It returns <tt><font size=+1>1</font></tt> is everything is ok, and <tt><font size=+1>0</font></tt> if an error was
found. Normally, one would not call these routines directly. Instead,
one sets the global variable <i>dbgbuild</i> and the library calls them
automatically. One can also set <i>warn</i>, to cause the library to
print a warning whenever it finds a problem with the input document,
and <i>dbglex</i>, to print debugging information in the
lexer.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
When an item list is finished with, it should be freed with <i>freeitems</i>.
Then, <i>freedocinfo</i> should be called on the pointer returned in
<tt><font size=+1>*</font></tt><i>pdi</i>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<i>Dimenkind</i> and <i>dimenspec</i> are provided to interpret the <tt><font size=+1>Dimen</font></tt> type,
as described in the section <i>Dimension Specifications</i>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Frame target names are mapped to integer ids via a global, permanent
mapping. To find the value for a given name, call <i>targetid</i>, which
allocates a new id if the name hasn’t been seen before. The name
of a given, known id may be retrieved using <i>targetname</i>. The library
predefines <tt><font size=+1>FTtop</font></tt>, <tt><font size=+1>FTself</font></tt>, <tt><font size=+1>FTparent</font></tt> and
<tt><font size=+1>FTblank</font></tt>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The library handles all text as Unicode strings (type <tt><font size=+1>Rune*</font></tt>).
Character set conversion is provided by <i>fromStr</i> and <i>toStr</i>. <i>FromStr</i>
takes <i>n</i> Unicode characters from <i>buf</i> and converts them to the character
set described by <i>chset</i>. <i>ToStr</i> takes <i>n</i> bytes from <i>buf</i>, interpretted
as belonging to character set <i>chset</i>, and converts
them to a Unicode string. Both routines null-terminate the result,
and use <tt><font size=+1>emalloc</font></tt> to allocate space for it.<br>
<p><font size=+1><b>Items </b></font><br>
The return value of <i>parsehtml</i> is a linked list of variant structures,
with the generic portion described by the following definition:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Item Item;<br>
struct Item<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item* next;<br>
int width;<br>
int height;<br>
int ascent;<br>
int anchorid;<br>
int state;<br>
Genattr* genattr;<br>
int tag;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
The field <tt><font size=+1>next</font></tt> points to the successor in the linked list of items,
while <tt><font size=+1>width</font></tt>, <tt><font size=+1>height</font></tt>, and <tt><font size=+1>ascent</font></tt> are intended for use by the caller
as part of the layout process. <tt><font size=+1>Anchorid</font></tt>, if non-zero, gives the
integer id assigned by the parser to the anchor that this item
is in (see section <i>Anchors</i>). <tt><font size=+1>State</font></tt> is a collection of
flags and values described as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>enum<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
IFbrk = 0x80000000,<br>
IFbrksp = 0x40000000,<br>
IFnobrk = 0x20000000,<br>
IFcleft = 0x10000000,<br>
IFcright = 0x08000000,<br>
IFwrap = 0x04000000,<br>
IFhang = 0x02000000,<br>
IFrjust = 0x01000000,<br>
IFcjust = 0x00800000,<br>
IFsmap = 0x00400000,<br>
IFindentshift = 8,<br>
IFindentmask = (255<<IFindentshift),<br>
IFhangmask = 255<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>IFbrk</font></tt> is set if a break is to be forced before placing this item.
<tt><font size=+1>IFbrksp</font></tt> is set if a 1 line space should be added to the break
(in which case <tt><font size=+1>IFbrk</font></tt> is also set). <tt><font size=+1>IFnobrk</font></tt> is set if a break is
not permitted before the item. <tt><font size=+1>IFcleft</font></tt> is set if left floats should
be cleared (that is, if the list of pending left floats should
be placed) before this item is placed, and <tt><font size=+1>IFcright</font></tt> is set for
right floats. In both cases, IFbrk is also set. <tt><font size=+1>IFwrap</font></tt> is set
if the line containing this item is allowed to wrap. <tt><font size=+1>IFhang</font></tt> is
set if this item hangs into the left indent. <tt><font size=+1>IFrjust</font></tt> is set if
the line containing this item should be right justified, and <tt><font size=+1>IFcjust</font></tt>
is
set for center justified lines. <tt><font size=+1>IFsmap</font></tt> is used to indicate that
an image is a server-side map. The low 8 bits, represented by
<tt><font size=+1>IFhangmask</font></tt>, indicate the current hang into left indent, in tenths
of a tabstop. The next 8 bits, represented by <tt><font size=+1>IFindentmask</font></tt> and
<tt><font size=+1>IFindentshift</font></tt>, indicate the current indent in tab
stops.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The field <tt><font size=+1>genattr</font></tt> is an optional pointer to an auxiliary structure,
described in the section <i>Generic Attributes</i>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Finally, <tt><font size=+1>tag</font></tt> describes which variant type this item has. It can
have one of the values <tt><font size=+1>Itexttag</font></tt>, <tt><font size=+1>Iruletag</font></tt>, <tt><font size=+1>Iimagetag</font></tt>, <tt><font size=+1>Iformfieldtag</font></tt>,
<tt><font size=+1>Itabletag</font></tt>, <tt><font size=+1>Ifloattag</font></tt> or <tt><font size=+1>Ispacertag</font></tt>. For each of these values,
there is an additional structure defined, which includes Item
as an unnamed initial substructure,
and then defines additional fields.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Items of type <tt><font size=+1>Itexttag</font></tt> represent a piece of text, using the following
structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Itext<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
Rune* s;<br>
int fnt;<br>
int fg;<br>
uchar voff;<br>
uchar ul;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Here <tt><font size=+1>s</font></tt> is a null-terminated Unicode string of the actual characters
making up this text item, <tt><font size=+1>fnt</font></tt> is the font number (described in
the section <i>Font Numbers</i>), and <tt><font size=+1>fg</font></tt> is the RGB encoded color for
the text. <tt><font size=+1>Voff</font></tt> measures the vertical offset from the baseline;
subtract <tt><font size=+1>Voffbias</font></tt> to get the actual value (negative values
represent a displacement down the page). The field <tt><font size=+1>ul</font></tt> is the underline
style: <tt><font size=+1>ULnone</font></tt> if no underline, <tt><font size=+1>ULunder</font></tt> for conventional underline,
and <tt><font size=+1>ULmid</font></tt> for strike-through.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Items of type <tt><font size=+1>Iruletag</font></tt> represent a horizontal rule, as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Irule<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
uchar align;<br>
uchar noshade;<br>
int size;<br>
Dimen wspec;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Here <tt><font size=+1>align</font></tt> is the alignment specification (described in the corresponding
section), <tt><font size=+1>noshade</font></tt> is set if the rule should not be shaded, <tt><font size=+1>size</font></tt>
is the height of the rule (as set by the size attribute), and
<tt><font size=+1>wspec</font></tt> is the desired width (see section <i>Dimension Specifications</i>).
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Items of type <tt><font size=+1>Iimagetag</font></tt> describe embedded images, for which the
following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Iimage<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
Rune* imsrc;<br>
int imwidth;<br>
int imheight;<br>
Rune* altrep;<br>
Map* map;<br>
int ctlid;<br>
uchar align;<br>
uchar hspace;<br>
uchar vspace;<br>
uchar border;<br>
Iimage* nextimage;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Here <tt><font size=+1>imsrc</font></tt> is the URL of the image source, <tt><font size=+1>imwidth</font></tt> and <tt><font size=+1>imheight</font></tt>,
if non-zero, contain the specified width and height for the image,
and <tt><font size=+1>altrep</font></tt> is the text to use as an alternative to the image,
if the image is not displayed. <tt><font size=+1>Map</font></tt>, if set, points to a structure
describing an associated client-side image map.
<tt><font size=+1>Ctlid</font></tt> is reserved for use by the application, for handling animated
images. <tt><font size=+1>Align</font></tt> encodes the alignment specification of the image.
<tt><font size=+1>Hspace</font></tt> contains the number of pixels to pad the image with on
either side, and <tt><font size=+1>Vspace</font></tt> the padding above and below. <tt><font size=+1>Border</font></tt> is
the width of the border to draw around the
image. <tt><font size=+1>Nextimage</font></tt> points to the next image in the document (the
head of this list is <tt><font size=+1>Docinfo.images</font></tt>).
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
For items of type <tt><font size=+1>Iformfieldtag</font></tt>, the following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Iformfield<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
Formfield* formfield;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
This adds a single field, <tt><font size=+1>formfield</font></tt>, which points to a structure
describing a field in a form, described in section <i>Forms</i>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
For items of type <tt><font size=+1>Itabletag</font></tt>, the following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Itable<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
Table* table;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Table</font></tt> points to a structure describing the table, described in
the section <i>Tables</i>.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
For items of type <tt><font size=+1>Ifloattag</font></tt>, the following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Ifloat<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
Item* item;<br>
int x;<br>
int y;<br>
uchar side;<br>
uchar infloats;<br>
Ifloat* nextfloat;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
The <tt><font size=+1>item</font></tt> points to a single item (either a table or an image)
that floats (the text of the document flows around it), and <tt><font size=+1>side</font></tt>
indicates the margin that this float sticks to; it is either <tt><font size=+1>ALleft</font></tt>
or <tt><font size=+1>ALright</font></tt>. <tt><font size=+1>X</font></tt> and <tt><font size=+1>y</font></tt> are reserved for use by the caller; these
are typically used for the coordinates of the top of the float.
<tt><font size=+1>Infloats</font></tt> is used by the caller to keep track of whether it has
placed the float. <tt><font size=+1>Nextfloat</font></tt> is used by the caller to link together
all of the floats that it has placed.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
For items of type <tt><font size=+1>Ispacertag</font></tt>, the following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>struct Ispacer<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Item;<br>
int spkind;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Spkind</font></tt> encodes the kind of spacer, and may be one of <tt><font size=+1>ISPnull</font></tt> (zero
height and width), <tt><font size=+1>ISPvline</font></tt> (takes on height and ascent of the
current font), <tt><font size=+1>ISPhspace</font></tt> (has the width of a space in the current
font) and <tt><font size=+1>ISPgeneral</font></tt> (for all other purposes, such as between
markers and lists).
<p><font size=+1><b>Generic Attributes </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The genattr field of an item, if non-nil, points to a structure
that holds the values of attributes not specific to any particular
item type, as they occur on a wide variety of underlying HTML
tags. The structure is as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Genattr Genattr;<br>
struct Genattr<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Rune* id;<br>
Rune* class;<br>
Rune* style;<br>
Rune* title;<br>
SEvent* events;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Fields <tt><font size=+1>id</font></tt>, <tt><font size=+1>class</font></tt>, <tt><font size=+1>style</font></tt> and <tt><font size=+1>title</font></tt>, when non-nil, contain values
of correspondingly named attributes of the HTML tag associated
with this item. <tt><font size=+1>Events</font></tt> is a linked list of events (with corresponding
scripted actions) associated with the item:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct SEvent SEvent;<br>
struct SEvent<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
SEvent* next;<br>
int type;<br>
Rune* script;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Here, <tt><font size=+1>next</font></tt> points to the next event in the list, <tt><font size=+1>type</font></tt> is one of
<tt><font size=+1>SEonblur</font></tt>, <tt><font size=+1>SEonchange</font></tt>, <tt><font size=+1>SEonclick</font></tt>, <tt><font size=+1>SEondblclick</font></tt>, <tt><font size=+1>SEonfocus</font></tt>, <tt><font size=+1>SEonkeypress</font></tt>,
<tt><font size=+1>SEonkeyup</font></tt>, <tt><font size=+1>SEonload</font></tt>, <tt><font size=+1>SEonmousedown</font></tt>, <tt><font size=+1>SEonmousemove</font></tt>, <tt><font size=+1>SEonmouseout</font></tt>,
<tt><font size=+1>SEonmouseover</font></tt>, <tt><font size=+1>SEonmouseup</font></tt>, <tt><font size=+1>SEonreset</font></tt>, <tt><font size=+1>SEonselect</font></tt>,
<tt><font size=+1>SEonsubmit</font></tt> or <tt><font size=+1>SEonunload</font></tt>, and <tt><font size=+1>script</font></tt> is the text of the associated
script.<br>
<p><font size=+1><b>Dimension Specifications </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Some structures include a dimension specification, used where
a number can be followed by a <tt><font size=+1>%</font></tt> or a <tt><font size=+1>*</font></tt> to indicate percentage
of total or relative weight. This is encoded using the following
structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Dimen Dimen;<br>
struct Dimen<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
int kindspec;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Separate kind and spec values are extracted using <i>dimenkind</i> and
<i>dimenspec</i>. <i>Dimenkind</i> returns one of <tt><font size=+1>Dnone</font></tt>, <tt><font size=+1>Dpixels</font></tt>, <tt><font size=+1>Dpercent</font></tt> or
<tt><font size=+1>Drelative</font></tt>. <tt><font size=+1>Dnone</font></tt> means that no dimension was specified. In all
other cases, <i>dimenspec</i> should be called to find the absolute number
of pixels, the percentage of total, or the
relative weight.<br>
<p><font size=+1><b>Background Specifications </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
It is possible to set the background of the entire document, and
also for some parts of the document (such as tables). This is
encoded as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Background Background;<br>
struct Background<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Rune* image;<br>
int color;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Image</font></tt>, if non-nil, is the URL of an image to use as the background.
If this is nil, <tt><font size=+1>color</font></tt> is used instead, as the RGB value for a
solid fill color.<br>
<p><font size=+1><b>Alignment Specifications </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Certain items have alignment specifiers taken from the following
enumerated type:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>enum<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
ALnone = 0, ALleft, ALcenter, ALright, ALjustify,<br>
ALchar, ALtop, ALmiddle, ALbottom, ALbaseline<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
These values correspond to the various alignment types named in
the HTML 4.0 standard. If an item has an alignment of <tt><font size=+1>ALleft</font></tt> or
<tt><font size=+1>ALright</font></tt>, the library automatically encapsulates it inside a float
item.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Tables, and the various rows, columns and cells within them, have
a more complex alignment specification, composed of separate vertical
and horizontal alignments:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Align Align;<br>
struct Align<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
uchar halign;<br>
uchar valign;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Halign</font></tt> can be one of <tt><font size=+1>ALnone</font></tt>, <tt><font size=+1>ALleft</font></tt>, <tt><font size=+1>ALcenter</font></tt>, <tt><font size=+1>ALright</font></tt>, <tt><font size=+1>ALjustify</font></tt>
or <tt><font size=+1>ALchar</font></tt>. <tt><font size=+1>Valign</font></tt> can be one of <tt><font size=+1>ALnone</font></tt>, <tt><font size=+1>ALmiddle</font></tt>, <tt><font size=+1>ALbottom</font></tt>, <tt><font size=+1>ALtop</font></tt>
or <tt><font size=+1>ALbaseline</font></tt>.<br>
<p><font size=+1><b>Font Numbers </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Text items have an associated font number (the <tt><font size=+1>fnt</font></tt> field), which
is encoded as <tt><font size=+1>style*NumSize+size</font></tt>. Here, <tt><font size=+1>style</font></tt> is one of <tt><font size=+1>FntR</font></tt>,
<tt><font size=+1>FntI</font></tt>, <tt><font size=+1>FntB</font></tt> or <tt><font size=+1>FntT</font></tt>, for roman, italic, bold and typewriter font
styles, respectively, and size is <tt><font size=+1>Tiny</font></tt>, <tt><font size=+1>Small</font></tt>, <tt><font size=+1>Normal</font></tt>, <tt><font size=+1>Large</font></tt> or
<tt><font size=+1>Verylarge</font></tt>. The total number of possible
font numbers is <tt><font size=+1>NumFnt</font></tt>, and the default font number is <tt><font size=+1>DefFnt</font></tt>
(which is roman style, normal size).<br>
<p><font size=+1><b>Document Info </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Global information about an HTML page is stored in the following
structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Docinfo Docinfo;<br>
struct Docinfo<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
// stuff from HTTP headers, doc head, and body tag<br>
Rune* src;<br>
Rune* base;<br>
Rune* doctitle;<br>
Background background;<br>
Iimage* backgrounditem;<br>
int text;<br>
int link;<br>
int vlink;<br>
int alink;<br>
int target;<br>
int chset;<br>
int mediatype;<br>
int scripttype;<br>
int hasscripts;<br>
Rune* refresh;<br>
Kidinfo* kidinfo;<br>
int frameid;<br>
// info needed to respond to user actions<br>
Anchor* anchors;<br>
DestAnchor* dests;<br>
Form* forms;<br>
Table* tables;<br>
Map* maps;<br>
Iimage* images;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Src</font></tt> gives the URL of the original source of the document, and
<tt><font size=+1>base</font></tt> is the base URL. <tt><font size=+1>Doctitle</font></tt> is the document’s title, as set
by a <tt><font size=+1><title></font></tt> element. <tt><font size=+1>Background</font></tt> is as described in the section
<i>Background Specifications</i>, and <tt><font size=+1>backgrounditem</font></tt> is set to be an
image item for the document’s background image
(if given as a URL), or else nil. <tt><font size=+1>Text</font></tt> gives the default foregound
text color of the document, <tt><font size=+1>link</font></tt> the unvisited hyperlink color,
<tt><font size=+1>vlink</font></tt> the visited hyperlink color, and <tt><font size=+1>alink</font></tt> the color for highlighting
hyperlinks (all in 24-bit RGB format). <tt><font size=+1>Target</font></tt> is the default target
frame id. <tt><font size=+1>Chset</font></tt> and <tt><font size=+1>mediatype</font></tt> are as for
the <i>chset</i> and <i>mtype</i> parameters to <i>parsehtml</i>. <tt><font size=+1>Scripttype</font></tt> is the
type of any scripts contained in the document, and is always <tt><font size=+1>TextJavascript</font></tt>.
<tt><font size=+1>Hasscripts</font></tt> is set if the document contains any scripts. Scripting
is currently unsupported. <tt><font size=+1>Refresh</font></tt> is the contents of a <tt><font size=+1><meta http−equiv=Refresh
...></font></tt> tag, if any. <tt><font size=+1>Kidinfo</font></tt> is set if this document is a frameset
(see section <i>Frames</i>). <tt><font size=+1>Frameid</font></tt> is this document’s frame id.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>Anchors</font></tt> is a list of hyperlinks contained in the document, and
<tt><font size=+1>dests</font></tt> is a list of hyperlink destinations within the page (see
the following section for details). <tt><font size=+1>Forms</font></tt>, <tt><font size=+1>tables</font></tt> and <tt><font size=+1>maps</font></tt> are
lists of the various forms, tables and client-side maps contained
in the document, as described in subsequent sections.
<tt><font size=+1>Images</font></tt> is a list of all the image items in the document.<br>
<p><font size=+1><b>Anchors </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The library builds two lists for all of the <tt><font size=+1><a></font></tt> elements (anchors)
in a document. Each anchor is assigned a unique anchor id within
the document. For anchors which are hyperlinks (the <tt><font size=+1>href</font></tt> attribute
was supplied), the following structure is defined:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Anchor Anchor;<br>
struct Anchor<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Anchor* next;<br>
int index;<br>
Rune* name;<br>
Rune* href;<br>
int target;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next anchor in the list (the head of this list
is <tt><font size=+1>Docinfo.anchors</font></tt>). <tt><font size=+1>Index</font></tt> is the anchor id; each item within
this hyperlink is tagged with this value in its <tt><font size=+1>anchorid</font></tt> field.
<tt><font size=+1>Name</font></tt> and <tt><font size=+1>href</font></tt> are the values of the correspondingly named attributes
of the anchor (in particular, href is the URL to go
to). <tt><font size=+1>Target</font></tt> is the value of the target attribute (if provided)
converted to a frame id.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Destinations within the document (anchors with the name attribute
set) are held in the <tt><font size=+1>Docinfo.dests</font></tt> list, using the following structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct DestAnchor DestAnchor;<br>
struct DestAnchor<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
DestAnchor* next;<br>
int index;<br>
Rune* name;<br>
Item* item;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> is the next element of the list, <tt><font size=+1>index</font></tt> is the anchor id,
<tt><font size=+1>name</font></tt> is the value of the name attribute, and <tt><font size=+1>item</font></tt> is points to
the item within the parsed document that should be considered
to be the destination.<br>
<p><font size=+1><b>Forms </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Any forms within a document are kept in a list, headed by <tt><font size=+1>Docinfo.forms</font></tt>.
The elements of this list are as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Form Form;<br>
struct Form<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Form* next;<br>
int formid;<br>
Rune* name;<br>
Rune* action;<br>
int target;<br>
int method;<br>
int nfields;<br>
Formfield* fields;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next form in the list. <tt><font size=+1>Formid</font></tt> is a serial number
for the form within the document. <tt><font size=+1>Name</font></tt> is the value of the form’s
name or id attribute. <tt><font size=+1>Action</font></tt> is the value of any action attribute.
<tt><font size=+1>Target</font></tt> is the value of the target attribute (if any) converted
to a frame target id. <tt><font size=+1>Method</font></tt> is one of <tt><font size=+1>HGet</font></tt> or
<tt><font size=+1>HPost</font></tt>. <tt><font size=+1>Nfields</font></tt> is the number of fields in the form, and <tt><font size=+1>fields</font></tt>
is a linked list of the actual fields.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The individual fields in a form are described by the following
structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Formfield Formfield;<br>
struct Formfield<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Formfield* next;<br>
int ftype;<br>
int fieldid;<br>
Form* form;<br>
Rune* name;<br>
Rune* value;<br>
int size;<br>
int maxlength;<br>
int rows;<br>
int cols;<br>
uchar flags;<br>
Option* options;<br>
Item* image;<br>
int ctlid;<br>
SEvent* events;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
Here, <tt><font size=+1>next</font></tt> points to the next field in the list. <tt><font size=+1>Ftype</font></tt> is the
type of the field, which can be one of <tt><font size=+1>Ftext</font></tt>, <tt><font size=+1>Fpassword</font></tt>, <tt><font size=+1>Fcheckbox</font></tt>,
<tt><font size=+1>Fradio</font></tt>, <tt><font size=+1>Fsubmit</font></tt>, <tt><font size=+1>Fhidden</font></tt>, <tt><font size=+1>Fimage</font></tt>, <tt><font size=+1>Freset</font></tt>, <tt><font size=+1>Ffile</font></tt>, <tt><font size=+1>Fbutton</font></tt>, <tt><font size=+1>Fselect</font></tt>
or <tt><font size=+1>Ftextarea</font></tt>. <tt><font size=+1>Fieldid</font></tt> is a serial number for the field within
the form. <tt><font size=+1>Form</font></tt> points back
to the form containing this field. <tt><font size=+1>Name</font></tt>, <tt><font size=+1>value</font></tt>, <tt><font size=+1>size</font></tt>, <tt><font size=+1>maxlength</font></tt>,
<tt><font size=+1>rows</font></tt> and <tt><font size=+1>cols</font></tt> each contain the values of corresponding attributes
of the field, if present. <tt><font size=+1>Flags</font></tt> contains per-field flags, of which
<tt><font size=+1>FFchecked</font></tt> and <tt><font size=+1>FFmultiple</font></tt> are defined. <tt><font size=+1>Image</font></tt> is only used for fields
of type <tt><font size=+1>Fimage</font></tt>; it points to an
image item containing the image to be displayed. <tt><font size=+1>Ctlid</font></tt> is reserved
for use by the caller, typically to store a unique id of an associated
control used to implement the field. <tt><font size=+1>Events</font></tt> is the same as the
corresponding field of the generic attributes associated with
the item containing this field. <tt><font size=+1>Options</font></tt> is only used by
fields of type <tt><font size=+1>Fselect</font></tt>; it consists of a list of possible options
that may be selected for that field, using the following structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Option Option;<br>
struct Option<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Option* next;<br>
int selected;<br>
Rune* value;<br>
Rune* display;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next element of the list. <tt><font size=+1>Selected</font></tt> is set if
this option is to be displayed initially. <tt><font size=+1>Value</font></tt> is the value to
send when the form is submitted if this option is selected. <tt><font size=+1>Display</font></tt>
is the string to display on the screen for this option.<br>
<p><font size=+1><b>Tables </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The library builds a list of all the tables in the document, headed
by <tt><font size=+1>Docinfo.tables</font></tt>. Each element of this list has the following
format:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Table Table;<br>
struct Table<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Table* next;<br>
int tableid;<br>
Tablerow* rows;<br>
int nrow;<br>
Tablecol* cols;<br>
int ncol;<br>
Tablecell* cells;<br>
int ncell;<br>
Tablecell*** grid;<br>
Align align;<br>
Dimen width;<br>
int border;<br>
int cellspacing;<br>
int cellpadding;<br>
Background background;<br>
Item* caption;<br>
uchar caption_place;<br>
Lay* caption_lay;<br>
int totw;<br>
int toth;<br>
int caph;<br>
int availw;<br>
Token* tabletok;<br>
uchar flags;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next element in the list of tables. <tt><font size=+1>Tableid</font></tt>
is a serial number for the table within the document. <tt><font size=+1>Rows</font></tt> is
an array of row specifications (described below) and <tt><font size=+1>nrow</font></tt> is the
number of elements in this array. Similarly, <tt><font size=+1>cols</font></tt> is an array
of column specifications, and <tt><font size=+1>ncol</font></tt> the size of this array.
<tt><font size=+1>Cells</font></tt> is a list of all cells within the table (structure described
below) and <tt><font size=+1>ncell</font></tt> is the number of elements in this list. Note
that a cell may span multiple rows and/or columns, thus <tt><font size=+1>ncell</font></tt>
may be smaller than <tt><font size=+1>nrow*ncol</font></tt>. <tt><font size=+1>Grid</font></tt> is a two-dimensional array
of cells within the table; the cell at row <tt><font size=+1>i</font></tt> and column <tt><font size=+1>j</font></tt> is
<tt><font size=+1>Table.grid[i][j]</font></tt>. A cell that spans multiple rows and/or columns
will be referenced by <tt><font size=+1>grid</font></tt> multiple times, however it will only
occur once in <tt><font size=+1>cells</font></tt>. <tt><font size=+1>Align</font></tt> gives the alignment specification for
the entire table, and <tt><font size=+1>width</font></tt> gives the requested width as a dimension
specification. <tt><font size=+1>Border</font></tt>, <tt><font size=+1>cellspacing
</font></tt>and <tt><font size=+1>cellpadding</font></tt> give the values of the corresponding attributes
for the table, and <tt><font size=+1>background</font></tt> gives the requested background for
the table. <tt><font size=+1>Caption</font></tt> is a linked list of items to be displayed as
the caption of the table, either above or below depending on whether
<tt><font size=+1>caption_place</font></tt> is <tt><font size=+1>ALtop</font></tt> or <tt><font size=+1>ALbottom</font></tt>.
Most of the remaining fields are reserved for use by the caller,
except <tt><font size=+1>tabletok</font></tt>, which is reserved for internal use. The type
<tt><font size=+1>Lay</font></tt> is not defined by the library; the caller can provide its
own definition.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The <tt><font size=+1>Tablecol</font></tt> structure is defined for use by the caller. The library
ensures that the correct number of these is allocated, but leaves
them blank. The fields are as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Tablecol Tablecol;<br>
struct Tablecol<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
int width;<br>
Align align;<br>
Point pos;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
The rows in the table are specified as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Tablerow Tablerow;<br>
struct Tablerow<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Tablerow* next;<br>
Tablecell* cells;<br>
int height;<br>
int ascent;<br>
Align align;<br>
Background background;<br>
Point pos;<br>
uchar flags;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> is only used during parsing; it should be ignored by the
caller. <tt><font size=+1>Cells</font></tt> provides a list of all the cells in a row, linked
through their <tt><font size=+1>nextinrow</font></tt> fields (see below). <tt><font size=+1>Height</font></tt>, <tt><font size=+1>ascent</font></tt> and
<tt><font size=+1>pos</font></tt> are reserved for use by the caller. <tt><font size=+1>Align</font></tt> is the alignment
specification for the row, and <tt><font size=+1>background</font></tt> is the
background to use, if specified. <tt><font size=+1>Flags</font></tt> is used by the parser;
ignore this field.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The individual cells of the table are described as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Tablecell Tablecell;<br>
struct Tablecell<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Tablecell* next;<br>
Tablecell* nextinrow;<br>
int cellid;<br>
Item* content;<br>
Lay* lay;<br>
int rowspan;<br>
int colspan;<br>
Align align;<br>
uchar flags;<br>
Dimen wspec;<br>
int hspec;<br>
Background background;<br>
int minw;<br>
int maxw;<br>
int ascent;<br>
int row;<br>
int col;<br>
Point pos;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> is used to link together the list of all cells within a table
(<tt><font size=+1>Table.cells</font></tt>), whereas <tt><font size=+1>nextinrow</font></tt> is used to link together all
the cells within a single row (<tt><font size=+1>Tablerow.cells</font></tt>). <tt><font size=+1>Cellid</font></tt> provides
a serial number for the cell within the table. <tt><font size=+1>Content</font></tt> is a linked
list of the items to be laid out within the cell. <tt><font size=+1>Lay
</font></tt>is reserved for the user to describe how these items have been
laid out. <tt><font size=+1>Rowspan</font></tt> and <tt><font size=+1>colspan</font></tt> are the number of rows and columns
spanned by this cell, respectively. <tt><font size=+1>Align</font></tt> is the alignment specification
for the cell. <tt><font size=+1>Flags</font></tt> is some combination of <tt><font size=+1>TFparsing</font></tt>, <tt><font size=+1>TFnowrap</font></tt>
and <tt><font size=+1>TFisth</font></tt> or’d together. Here
<tt><font size=+1>TFparsing</font></tt> is used internally by the parser, and should be ignored.
<tt><font size=+1>TFnowrap</font></tt> means that the contents of the cell should not be wrapped
if they don’t fit the available width, rather, the table should
be expanded if need be (this is set when the nowrap attribute
is supplied). <tt><font size=+1>TFisth</font></tt> means that the cell was created
by the <tt><font size=+1><th></font></tt> element (rather than the <tt><font size=+1><td></font></tt> element), indicating that
it is a header cell rather than a data cell. <tt><font size=+1>Wspec</font></tt> provides a
suggested width as a dimension specification, and <tt><font size=+1>hspec</font></tt> provides
a suggested height in pixels. <tt><font size=+1>Background</font></tt> gives a background specification
for the individual cell. <tt><font size=+1>Minw</font></tt>, <tt><font size=+1>maxw</font></tt>,
<tt><font size=+1>ascent</font></tt> and <tt><font size=+1>pos</font></tt> are reserved for use by the caller during layout.
<tt><font size=+1>Row</font></tt> and <tt><font size=+1>col</font></tt> give the indices of the row and column of the top
left-hand corner of the cell within the table grid.<br>
<p><font size=+1><b>Client-side Maps </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The library builds a list of client-side maps, headed by <tt><font size=+1>Docinfo.maps</font></tt>,
and having the following structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Map Map;<br>
struct Map<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Map* next;<br>
Rune* name;<br>
Area* areas;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next element in the list, <tt><font size=+1>name</font></tt> is the name
of the map (use to bind it to an image), and <tt><font size=+1>areas</font></tt> is a list of
the areas within the image that comprise the map, using the following
structure:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Area Area;<br>
struct Area<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Area* next;<br>
int shape;<br>
Rune* href;<br>
int target;<br>
Dimen* coords;<br>
int ncoords;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> points to the next element in the map’s list of areas. <tt><font size=+1>Shape</font></tt>
describes the shape of the area, and is one of <tt><font size=+1>SHrect</font></tt>, <tt><font size=+1>SHcircle</font></tt>
or <tt><font size=+1>SHpoly</font></tt>. <tt><font size=+1>Href</font></tt> is the URL associated with this area in its role
as a hypertext link, and <tt><font size=+1>target</font></tt> is the target frame it should
be loaded in. <tt><font size=+1>Coords</font></tt> is an array of coordinates for
the shape, and <tt><font size=+1>ncoords</font></tt> is the size of this array (number of elements).<br>
<p><font size=+1><b>Frames </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
If the <tt><font size=+1>Docinfo.kidinfo</font></tt> field is set, the document is a frameset.
In this case, it is typical for <i>parsehtml</i> to return nil, as a
document which is a frameset should have no actual items that
need to be laid out (such will appear only in subsidiary documents).
It is possible that items will be returned by a malformed
document; the caller should check for this and free any such items.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The <tt><font size=+1>Kidinfo</font></tt> structure itself reflects the fact that framesets
can be nested within a document. If is defined as follows:
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
<tt><font size=+1>typedef struct Kidinfo Kidinfo;<br>
struct Kidinfo<br>
{<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
Kidinfo* next;<br>
int isframeset;<br>
// fields for "frame"<br>
Rune* src;<br>
Rune* name;<br>
int marginw;<br>
int marginh;<br>
int framebd;<br>
int flags;<br>
// fields for "frameset"<br>
Dimen* rows;<br>
int nrows;<br>
Dimen* cols;<br>
int ncols;<br>
Kidinfo* kidinfos;<br>
Kidinfo* nextframeset;<br>
</table>
};<br>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
</font></tt>
<tt><font size=+1>Next</font></tt> is only used if this structure is part of a containing frameset;
it points to the next element in the list of children of that
frameset. <tt><font size=+1>Isframeset</font></tt> is set when this structure represents a frameset;
if clear, it is an individual frame.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
Some fields are used only for framesets. <tt><font size=+1>Rows</font></tt> is an array of dimension
specifications for rows in the frameset, and <tt><font size=+1>nrows</font></tt> is the length
of this array. <tt><font size=+1>Cols</font></tt> is the corresponding array for columns, of
length <tt><font size=+1>ncols</font></tt>. <tt><font size=+1>Kidinfos</font></tt> points to a list of components contained
within this frameset, each of which may be a
frameset or a frame. <tt><font size=+1>Nextframeset</font></tt> is only used during parsing,
and should be ignored.
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
The remaining fields are used if the structure describes a frame,
not a frameset. <tt><font size=+1>Src</font></tt> provides the URL for the document that should
be initially loaded into this frame. Note that this may be a relative
URL, in which case it should be interpretted using the containing
document’s URL as the base. <tt><font size=+1>Name</font></tt> gives the name of
the frame, typically supplied via a name attribute in the HTML.
If no name was given, the library allocates one. <tt><font size=+1>Marginw</font></tt>, <tt><font size=+1>marginh</font></tt>
and <tt><font size=+1>framebd</font></tt> are the values of the marginwidth, marginheight and
frameborder attributes, respectively. <tt><font size=+1>Flags</font></tt> can contain some combination
of the following: <tt><font size=+1>FRnoresize</font></tt> (the
frame had the noresize attribute set, and the user should not
be allowed to resize it), <tt><font size=+1>FRnoscroll</font></tt> (the frame should not have
any scroll bars), <tt><font size=+1>FRhscroll</font></tt> (the frame should have a horizontal
scroll bar), <tt><font size=+1>FRvscroll</font></tt> (the frame should have a vertical scroll
bar), <tt><font size=+1>FRhscrollauto</font></tt> (the frame should be automatically
given a horizontal scroll bar if its contents would not otherwise
fit), and <tt><font size=+1>FRvscrollauto</font></tt> (the frame gets a vertical scrollbar only
if required).<br>
</table>
<p><font size=+1><b>SOURCE </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
<tt><font size=+1>/usr/local/plan9/src/libhtml<br>
</font></tt>
</table>
<p><font size=+1><b>SEE ALSO </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
<a href="../man1/fmt.html"><i>fmt</i>(1)</a>
<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table>
W3C World Wide Web Consortium, “HTML 4.01 Specification”.<br>
</table>
<p><font size=+1><b>BUGS </b></font><br>
<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td>
The entire HTML document must be loaded into memory before any
of it can be parsed.<br>
</table>
<td width=20>
<tr height=20><td>
</table>
<!-- TRAILER -->
<table border=0 cellpadding=0 cellspacing=0 width=100%>
<tr height=15><td width=10><td><td width=10>
<tr><td><td>
<center>
<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a>
</center>
</table>
<!-- TRAILER -->
</body></html>
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