stylesheet.c File Reference

#include <assert.h>
#include <string.h>
#include <stdarg.h>
#include "stylesheet.h"
#include "bytecode/bytecode.h"
#include "parse/language.h"
#include "parse/mq.h"
#include "utils/parserutilserror.h"
#include "utils/utils.h"
#include "select/dispatch.h"
#include "select/font_face.h"

Macros
#define	CSS_STYLE_DEFAULT_SIZE   16

Functions
css_error	css__stylesheet_string_add (css_stylesheet *sheet, lwc_string *string, uint32_t *string_number)
css_error	css__stylesheet_string_get (css_stylesheet *sheet, uint32_t string_number, lwc_string **string)
css_error	css_stylesheet_create (const css_stylesheet_params *params, css_stylesheet **stylesheet)
css_error	css_stylesheet_destroy (css_stylesheet *sheet)
css_error	css_stylesheet_append_data (css_stylesheet *sheet, const uint8_t *data, size_t len)
css_error	css_stylesheet_data_done (css_stylesheet *sheet)
css_error	css_stylesheet_next_pending_import (css_stylesheet *parent, lwc_string **url)
css_error	css_stylesheet_register_import (css_stylesheet *parent, css_stylesheet *import)
css_error	css_stylesheet_get_language_level (css_stylesheet *sheet, css_language_level *level)
css_error	css_stylesheet_get_url (css_stylesheet *sheet, const char **url)
css_error	css_stylesheet_get_title (css_stylesheet *sheet, const char **title)
css_error	css_stylesheet_quirks_allowed (css_stylesheet *sheet, bool *allowed)
css_error	css_stylesheet_used_quirks (css_stylesheet *sheet, bool *quirks)
css_error	css_stylesheet_get_disabled (css_stylesheet *sheet, bool *disabled)
css_error	css_stylesheet_set_disabled (css_stylesheet *sheet, bool disabled)
css_error	css_stylesheet_size (css_stylesheet *sheet, size_t *size)
css_error	css__stylesheet_style_create (css_stylesheet *sheet, css_style **style)
css_error	css__stylesheet_merge_style (css_style *target, css_style *style)
css_error	css__stylesheet_style_vappend (css_style *style, uint32_t style_count,...)
css_error	css__stylesheet_style_append (css_style *style, css_code_t css_code)
css_error	css__stylesheet_style_destroy (css_style *style)
css_error	css__stylesheet_selector_create (css_stylesheet *sheet, css_qname *qname, css_selector **selector)
css_error	css__stylesheet_selector_destroy (css_stylesheet *sheet, css_selector *selector)
css_error	css__stylesheet_selector_detail_init (css_stylesheet *sheet, css_selector_type type, css_qname *qname, css_selector_detail_value value, css_selector_detail_value_type value_type, bool negate, css_selector_detail *detail)
css_error	css__stylesheet_selector_append_specific (css_stylesheet *sheet, css_selector **parent, const css_selector_detail *detail)
css_error	css__stylesheet_selector_combine (css_stylesheet *sheet, css_combinator type, css_selector *a, css_selector *b)
css_error	css__stylesheet_rule_create (css_stylesheet *sheet, css_rule_type type, css_rule **rule)
css_error	css__stylesheet_rule_destroy (css_stylesheet *sheet, css_rule *rule)
css_error	css__stylesheet_rule_add_selector (css_stylesheet *sheet, css_rule *rule, css_selector *selector)
css_error	css__stylesheet_rule_append_style (css_stylesheet *sheet, css_rule *rule, css_style *style)
css_error	css__stylesheet_rule_set_charset (css_stylesheet *sheet, css_rule *rule, lwc_string *charset)
css_error	css__stylesheet_rule_set_nascent_import (css_stylesheet *sheet, css_rule *rule, lwc_string *url, css_mq_query *media)
css_error	css__stylesheet_rule_set_media (css_stylesheet *sheet, css_rule *rule, css_mq_query *media)
css_error	css__stylesheet_rule_set_page_selector (css_stylesheet *sheet, css_rule *rule, css_selector *selector)
css_error	css__stylesheet_add_rule (css_stylesheet *sheet, css_rule *rule, css_rule *parent)
css_error	css__stylesheet_remove_rule (css_stylesheet *sheet, css_rule *rule)

Macro Definition Documentation

CSS_STYLE_DEFAULT_SIZE

#define CSS_STYLE_DEFAULT_SIZE   16

Function Documentation

css__stylesheet_add_rule()

css_error css__stylesheet_add_rule	(	css_stylesheet *	sheet,
		css_rule *	rule,
		css_rule *	parent
	)

Add a rule to a stylesheet

Parameters

sheet	The stylesheet to add to
rule	The rule to add
parent	The parent rule, or NULL for a top-level rule

Returns

CSS_OK on success, appropriate error otherwise

Todo:

needs to trigger some event announcing styles have changed

css__stylesheet_merge_style()

css_error css__stylesheet_merge_style	(	css_style *	target,
		css_style *	style
	)

css__stylesheet_remove_rule()

css_error css__stylesheet_remove_rule	(	css_stylesheet *	sheet,
		css_rule *	rule
	)

Remove a rule from a stylesheet

Parameters

sheet	The sheet to remove from
rule	The rule to remove

Returns

CSS_OK on success, appropriate error otherwise

\ todo renumber subsequent rules? may not be necessary, as there's only an expectation that rules which occur later in the stylesheet have a higher index than those that appear earlier. There's no guarantee that the number space is continuous.

Todo:

needs to trigger some event announcing styles have changed

css__stylesheet_rule_add_selector()

css_error css__stylesheet_rule_add_selector	(	css_stylesheet *	sheet,
		css_rule *	rule,
		css_selector *	selector
	)

Add a selector to a CSS rule

Parameters

sheet	The stylesheet context
rule	The rule to add to (must be of type CSS_RULE_SELECTOR)
selector	The selector to add

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_append_style()

css_error css__stylesheet_rule_append_style	(	css_stylesheet *	sheet,
		css_rule *	rule,
		css_style *	style
	)

Append a style to a CSS rule

Parameters

sheet	The stylesheet context
rule	The rule to add to (must be CSS_RULE_SELECTOR or CSS_RULE_PAGE)
style	The style to add

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_create()

css_error css__stylesheet_rule_create	(	css_stylesheet *	sheet,
		css_rule_type	type,
		css_rule **	rule
	)

Create a CSS rule

Parameters

sheet	The stylesheet context
type	The rule type
rule	Pointer to location to receive rule object

Returns

CSS_OK on success, CSS_BADPARM on bad parameters, CSS_NOMEM on memory exhaustion

css__stylesheet_rule_destroy()

css_error css__stylesheet_rule_destroy	(	css_stylesheet *	sheet,
		css_rule *	rule
	)

Destroy a CSS rule

Parameters

sheet	The stylesheet context
rule	The rule to destroy

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_set_charset()

css_error css__stylesheet_rule_set_charset	(	css_stylesheet *	sheet,
		css_rule *	rule,
		lwc_string *	charset
	)

Set the charset of a CSS rule

Parameters

sheet	The stylesheet context
rule	The rule to add to (must be of type CSS_RULE_CHARSET)
charset	The charset

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_set_media()

css_error css__stylesheet_rule_set_media	(	css_stylesheet *	sheet,
		css_rule *	rule,
		css_mq_query *	media
	)

Set the media of an @media rule

Parameters

sheet	The stylesheet context
rule	The rule to add to (must be of type CSS_RULE_MEDIA)
media	The applicable media types for the rule

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_set_nascent_import()

css_error css__stylesheet_rule_set_nascent_import	(	css_stylesheet *	sheet,
		css_rule *	rule,
		lwc_string *	url,
		css_mq_query *	media
	)

Set the necessary data to import a stylesheet associated with a rule

Parameters

sheet	The stylesheet context
rule	The rule to add to (must be of type CSS_RULE_IMPORT)
url	The URL of the imported stylesheet
media	The applicable media types for the imported stylesheet

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_rule_set_page_selector()

css_error css__stylesheet_rule_set_page_selector	(	css_stylesheet *	sheet,
		css_rule *	rule,
		css_selector *	selector
	)

Todo:

validate selector

css__stylesheet_selector_append_specific()

css_error css__stylesheet_selector_append_specific	(	css_stylesheet *	sheet,
		css_selector **	parent,
		const css_selector_detail *	detail
	)

Append a selector to the specifics chain of another selector

Parameters

sheet	The stylesheet context
parent	Pointer to pointer to the parent selector (updated on exit)
specific	The selector to append (copied)

Returns

CSS_OK on success, appropriate error otherwise.

Todo:

this may want optimising – counting blocks is O(n) In practice, however, n isn't likely to be large, so may be fine

css__stylesheet_selector_combine()

css_error css__stylesheet_selector_combine	(	css_stylesheet *	sheet,
		css_combinator	type,
		css_selector *	a,
		css_selector *	b
	)

Combine a pair of selectors

Parameters

sheet	The stylesheet context
type	The combinator type
a	The first operand
b	The second operand

Returns

CSS_OK on success, appropriate error otherwise.

For example, given A + B, the combinator field of B would point at A, with a combinator type of CSS_COMBINATOR_SIBLING. Thus, given B, we can find its combinator. It is not possible to find B given A.

css__stylesheet_selector_create()

css_error css__stylesheet_selector_create	(	css_stylesheet *	sheet,
		css_qname *	qname,
		css_selector **	selector
	)

Create an element selector

Parameters

sheet	The stylesheet context
qname	Qualified name of selector
selector	Pointer to location to receive selector object

Returns

CSS_OK on success, CSS_BADPARM on bad parameters, CSS_NOMEM on memory exhaustion

css__stylesheet_selector_destroy()

css_error css__stylesheet_selector_destroy	(	css_stylesheet *	sheet,
		css_selector *	selector
	)

Destroy a selector object

Parameters

sheet	The stylesheet context
selector	The selector to destroy

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_selector_detail_init()

css_error css__stylesheet_selector_detail_init	(	css_stylesheet *	sheet,
		css_selector_type	type,
		css_qname *	qname,
		css_selector_detail_value	value,
		css_selector_detail_value_type	value_type,
		bool	negate,
		css_selector_detail *	detail
	)

Initialise a selector detail

Parameters

sheet	The stylesheet context
type	The type of selector to create
qname	Qualified name of selector
value	Value of selector
value_type	Type of value
negate	Whether the detail match should be negated
detail	Pointer to detail object to initialise

Returns

CSS_OK on success, CSS_BADPARM on bad parameters

Note

No strings are referenced at this point: they will be referenced when appending the detail to a selector.

css__stylesheet_string_add()

css_error css__stylesheet_string_add	(	css_stylesheet *	sheet,
		lwc_string *	string,
		uint32_t *	string_number
	)

Add a string to a stylesheet's string vector.

Parameters

sheet	The stylesheet to add string to.
string	The string to add.
string_number	Pointer to location to receive string number.

Returns

CSS_OK on success, CSS_BADPARM on bad parameters, CSS_NOMEM on memory exhaustion

Postcondition

Ownership of string reference is passed to the stylesheet (even on failure)

Note

The returned string number is guaranteed to be non-zero

css__stylesheet_string_get()

css_error css__stylesheet_string_get	(	css_stylesheet *	sheet,
		uint32_t	string_number,
		lwc_string **	string
	)

Get a string from a stylesheet's string vector.

Parameters

sheet	The stylesheet to retrive string from.
string_number	The string number to retrive.
string	Pointer to location to receive string.

Returns

CSS_OK on success, CSS_BADPARM on bad parameters,

css__stylesheet_style_append()

css_error css__stylesheet_style_append	(	css_style *	style,
		css_code_t	css_code
	)

append a css code entry to a style

css__stylesheet_style_create()

css_error css__stylesheet_style_create	(	css_stylesheet *	sheet,
		css_style **	style
	)

Create a style

Parameters

sheet	The stylesheet context
len	The required length of the style
style	Pointer to location to receive style

Returns

CSS_OK on success, CSS_BADPARM on bad parameters, CSS_NOMEM on memory exhaustion

css__stylesheet_style_destroy()

css_error css__stylesheet_style_destroy

(

css_style *

style

)

Destroy a style

Parameters

sheet	The stylesheet context
style	The style to destroy

Returns

CSS_OK on success, appropriate error otherwise

css__stylesheet_style_vappend()

css_error css__stylesheet_style_vappend	(	css_style *	style,
		uint32_t	style_count,
			...
	)

append one or more css code entries to a style

css_stylesheet_append_data()

css_error css_stylesheet_append_data	(	css_stylesheet *	sheet,
		const uint8_t *	data,
		size_t	len
	)

Append source data to a stylesheet

Parameters

sheet	The stylesheet to append data to
data	Pointer to data to append
len	Length, in bytes, of data to append

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_create()

css_error css_stylesheet_create	(	const css_stylesheet_params *	params,
		css_stylesheet **	stylesheet
	)

Create a stylesheet

Parameters

params	Stylesheet parameters
stylesheet	Pointer to location to receive stylesheet

Returns

CSS_OK on success, CSS_BADPARM on bad parameters, CSS_NOMEM on memory exhaustion

css_stylesheet_data_done()

css_error css_stylesheet_data_done

(

css_stylesheet *

sheet

)

Flag that the last of a stylesheet's data has been seen

Parameters

sheet

The stylesheet in question

Returns

CSS_OK on success, CSS_IMPORTS_PENDING if there are imports pending, appropriate error otherwise

css_stylesheet_destroy()

css_error css_stylesheet_destroy

(

css_stylesheet *

sheet

)

Destroy a stylesheet

Parameters

sheet

The stylesheet to destroy

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_get_disabled()

css_error css_stylesheet_get_disabled	(	css_stylesheet *	sheet,
		bool *	disabled
	)

Get disabled status of a stylesheet

Parameters

sheet	The stylesheet to consider
disabled	Pointer to location to receive disabled state

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_get_language_level()

css_error css_stylesheet_get_language_level	(	css_stylesheet *	sheet,
		css_language_level *	level
	)

Retrieve the language level of a stylesheet

Parameters

sheet	The stylesheet to retrieve the language level of
level	Pointer to location to receive language level

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_get_title()

css_error css_stylesheet_get_title	(	css_stylesheet *	sheet,
		const char **	title
	)

Retrieve the title associated with a stylesheet

Parameters

sheet	The stylesheet to retrieve the title from
title	Pointer to location to receive pointer to title

Returns

CSS_Ok on success, appropriate error otherwise

css_stylesheet_get_url()

css_error css_stylesheet_get_url	(	css_stylesheet *	sheet,
		const char **	url
	)

Retrieve the URL associated with a stylesheet

Parameters

sheet	The stylesheet to retrieve the URL from
url	Pointer to location to receive pointer to URL

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_next_pending_import()

css_error css_stylesheet_next_pending_import	(	css_stylesheet *	parent,
		lwc_string **	url
	)

Retrieve the next pending import for the parent stylesheet

Parameters

parent	Parent stylesheet
url	Pointer to object to be populated with details of URL of imported stylesheet (potentially relative)

Returns

CSS_OK on success, CSS_INVALID if there are no pending imports remaining

The client must resolve the absolute URL of the imported stylesheet, using the parent's URL as the base. It must then fetch the imported stylesheet, and parse it to completion, including fetching any stylesheets it may import. The resultant sheet must then be registered with the parent using css_stylesheet_register_import().

The client must then call this function again, to determine if there are any further imports for the parent stylesheet, and, if so, process them as described above.

If the client is unable to fetch an imported stylesheet, it must register an empty stylesheet with the parent in its place.

css_stylesheet_quirks_allowed()

css_error css_stylesheet_quirks_allowed	(	css_stylesheet *	sheet,
		bool *	allowed
	)

Determine whether quirky parsing was permitted on a stylesheet

Parameters

sheet	The stylesheet to consider
quirks	Pointer to location to receive quirkyness

Returns

CSS_OK on success, appropriate error otherwise

css_stylesheet_register_import()

css_error css_stylesheet_register_import	(	css_stylesheet *	parent,
		css_stylesheet *	import
	)

Register an imported stylesheet with its parent

Parameters

parent	Parent stylesheet
import	Imported sheet

Returns

CSS_OK on success, CSS_INVALID if there are no outstanding imports, appropriate error otherwise.

Ownership of the imported stylesheet is retained by the client.

css_stylesheet_set_disabled()

css_error css_stylesheet_set_disabled	(	css_stylesheet *	sheet,
		bool	disabled
	)

Set a stylesheet's disabled state

Parameters

sheet	The stylesheet to modify
disabled	The new disabled state

Returns

CSS_OK on success, appropriate error otherwise

Todo:

needs to trigger some event announcing styles have changed

css_stylesheet_size()

css_error css_stylesheet_size	(	css_stylesheet *	sheet,
		size_t *	size
	)

Determine the memory-resident size of a stylesheet

Parameters

sheet	Sheet to consider
size	Pointer to location to receive byte count

Returns

CSS_OK on success.

Note

The returned size will not include the size of interned strings or imported stylesheets.

css_stylesheet_used_quirks()

css_error css_stylesheet_used_quirks	(	css_stylesheet *	sheet,
		bool *	quirks
	)

Determine whether quirky parsing was used on a stylesheet

Parameters

sheet	The stylesheet to consider
quirks	Pointer to location to receive quirkyness

Returns

CSS_OK on success, appropriate error otherwise