netsurf/css/css.c

1522 lines
41 KiB
C

/*
* This file is part of NetSurf, http://netsurf.sourceforge.net/
* Licensed under the GNU General Public License,
* http://www.opensource.org/licenses/gpl-license
* Copyright 2004 James Bursa <bursa@users.sourceforge.net>
*/
/** \file
* CSS handling (implementation).
*
* See CSS 2.1 chapter 5 for the terms used here.
*
* CSS style sheets are stored as a hash table mapping selectors to styles.
* Selectors are hashed by the <em>type selector</em> of the last <em>simple
* selector</em> in the selector. The <em>universal selector</em> is hashed to
* chain 0.
*
* A <em>simple selector</em> is a struct css_selector with type
* CSS_SELECTOR_ELEMENT. The data field is the <em>type selector</em>, or 0 for
* the <em>universal selector</em>. Any <em>attribute selectors</em>, <em>ID
* selectors</em>, or <em>pseudo-classes</em> form a linked list of
* css_selector hanging from detail.
*
* A <em>selector</em> is a linked list by the combiner field of these simple
* selectors, in reverse order that they appear in the concrete syntax. The last
* simple selector is first, then the previous one is linked at combiner and has
* relationship comb to the last, etc.
*
* Selectors are then linked in each hash chain by next, in order of increasing
* specificity.
*
* As an example, the stylesheet
* \code
* th { [1] }
* div#id1 > h4.class1 { [2] }
* center * { [3] } \endcode
*
* would result in a struct css_stylesheet (content::data.css.css) like this
* \dot
* digraph example {
* node [shape=record, fontname=Helvetica, fontsize=9];
* edge [fontname=Helvetica, fontsize=9];
* css -> n0 [label="rule[0]"];
* css -> n2 [label="rule[29]"];
*
* n0 [label="css_selector\ntype CSS_SELECTOR_ELEMENT\ldata 0\lcomb CSS_COMB_ANCESTOR\lspecificity 2\l"];
* n0 -> n1 [label="combiner"];
* n0 -> n0style [label="style"]; n0style [label="[3]"];
*
* n1 [label="css_selector\ntype CSS_SELECTOR_ELEMENT\ldata \"center\"\lcomb CSS_COMB_NONE\lspecificity 1\l"];
*
* n2 [label="css_selector\ntype CSS_SELECTOR_ELEMENT\ldata \"th\"\lcomb CSS_COMB_NONE\lspecificity 1\l"];
* n2 -> n3 [label="next"];
* n2 -> n2style [label="style"]; n2style [label="[1]"];
*
* n3 [label="css_selector\ntype CSS_SELECTOR_ELEMENT\ldata \"h4\"\lcomb CSS_COMB_PARENT\lspecificity 0x10102\l"];
* n3 -> n4 [label="detail"];
* n3 -> n5 [label="combiner"];
* n3 -> n3style [label="style"]; n3style [label="[2]"];
*
* n4 [label="css_selector\ntype CSS_SELECTOR_CLASS\ldata \"class1\"\lcomb CSS_COMB_NONE\lspecificity 0x100\l"];
*
* n5 [label="css_selector\ntype CSS_SELECTOR_ELEMENT\ldata \"div\"\lcomb CSS_COMB_NONE\lspecificity 0x10001\l"];
* n5 -> n6 [label="detail"];
*
* n6 [label="css_selector\ntype CSS_SELECTOR_ID\ldata \"#id1\"\lcomb CSS_COMB_NONE\lspecificity 0x10000\l"];
* }
* \enddot
*
* (any fields not shown are 0). In this example the first two rules happen to
* have hashed to the same value.
*/
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#define CSS_INTERNALS
#undef NDEBUG
#include "netsurf/utils/config.h"
#include "netsurf/content/content.h"
#include "netsurf/content/fetch.h"
#include "netsurf/content/fetchcache.h"
#include "netsurf/css/css.h"
#include "netsurf/css/parser.h"
#ifdef riscos
#include "netsurf/desktop/gui.h"
#endif
#include "netsurf/utils/log.h"
#include "netsurf/utils/url.h"
#include "netsurf/utils/utils.h"
static void css_atimport_callback(content_msg msg, struct content *css,
void *p1, void *p2, union content_msg_data data);
static bool css_match_rule(struct css_selector *rule, xmlNode *element);
static bool css_match_detail(const struct css_selector *detail,
xmlNode *element);
static void css_dump_length(const struct css_length * const length);
static void css_dump_selector(const struct css_selector *r);
/** Default style for a document. These are the 'Initial values' from the
* spec. */
const struct css_style css_base_style = {
0xffffff,
{ { 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE } },
CSS_CLEAR_NONE,
0x000000,
CSS_CURSOR_AUTO,
CSS_DISPLAY_BLOCK,
CSS_FLOAT_NONE,
{ CSS_FONT_SIZE_LENGTH, { { 10, CSS_UNIT_PT } } },
CSS_FONT_FAMILY_SANS_SERIF,
CSS_FONT_WEIGHT_NORMAL,
CSS_FONT_STYLE_NORMAL,
CSS_FONT_VARIANT_NORMAL,
{ CSS_HEIGHT_AUTO, { 1, CSS_UNIT_EM } },
{ CSS_LINE_HEIGHT_ABSOLUTE, { 1.3 } },
{ { CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } } },
{ { CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } } },
CSS_TEXT_ALIGN_LEFT,
CSS_TEXT_DECORATION_NONE,
{ CSS_TEXT_INDENT_LENGTH, { { 0, CSS_UNIT_EM } } },
CSS_TEXT_TRANSFORM_NONE,
CSS_VISIBILITY_VISIBLE,
{ CSS_WIDTH_AUTO, { { 1, CSS_UNIT_EM } } },
CSS_WHITE_SPACE_NORMAL
};
/** Style with no values set. */
const struct css_style css_empty_style = {
CSS_COLOR_INHERIT,
{ { CSS_COLOR_INHERIT, { CSS_BORDER_WIDTH_INHERIT,
{ 0, CSS_UNIT_PX } }, CSS_BORDER_STYLE_INHERIT },
{ CSS_COLOR_INHERIT, { CSS_BORDER_WIDTH_INHERIT,
{ 0, CSS_UNIT_PX } }, CSS_BORDER_STYLE_INHERIT },
{ CSS_COLOR_INHERIT, { CSS_BORDER_WIDTH_INHERIT,
{ 0, CSS_UNIT_PX } }, CSS_BORDER_STYLE_INHERIT },
{ CSS_COLOR_INHERIT, { CSS_BORDER_WIDTH_INHERIT,
{ 0, CSS_UNIT_PX } }, CSS_BORDER_STYLE_INHERIT } },
CSS_CLEAR_INHERIT,
CSS_COLOR_INHERIT,
CSS_CURSOR_INHERIT,
CSS_DISPLAY_INHERIT,
CSS_FLOAT_INHERIT,
{ CSS_FONT_SIZE_INHERIT, { { 1, CSS_UNIT_EM } } },
CSS_FONT_FAMILY_INHERIT,
CSS_FONT_WEIGHT_INHERIT,
CSS_FONT_STYLE_INHERIT,
CSS_FONT_VARIANT_INHERIT,
{ CSS_HEIGHT_INHERIT, { 1, CSS_UNIT_EM } },
{ CSS_LINE_HEIGHT_INHERIT, { 1.3 } },
{ { CSS_MARGIN_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_INHERIT, { { 0, CSS_UNIT_PX } } } },
{ { CSS_PADDING_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_INHERIT, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_INHERIT, { { 0, CSS_UNIT_PX } } } },
CSS_TEXT_ALIGN_INHERIT,
CSS_TEXT_DECORATION_INHERIT,
{ CSS_TEXT_INDENT_INHERIT, { { 0, CSS_UNIT_EM } } },
CSS_TEXT_TRANSFORM_INHERIT,
CSS_VISIBILITY_INHERIT,
{ CSS_WIDTH_INHERIT, { { 1, CSS_UNIT_EM } } },
CSS_WHITE_SPACE_INHERIT
};
/** Default style for an element. These should be INHERIT if 'Inherited' is yes,
* and the 'Initial value' otherwise. */
const struct css_style css_blank_style = {
TRANSPARENT,
{ { 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE },
{ 0x000000, { CSS_BORDER_WIDTH_LENGTH,
{ 2, CSS_UNIT_PX } }, CSS_BORDER_STYLE_NONE } },
CSS_CLEAR_NONE,
CSS_COLOR_INHERIT,
CSS_CURSOR_INHERIT,
CSS_DISPLAY_INLINE,
CSS_FLOAT_NONE,
{ CSS_FONT_SIZE_INHERIT, { { 1, CSS_UNIT_EM } } },
CSS_FONT_FAMILY_INHERIT,
CSS_FONT_WEIGHT_INHERIT,
CSS_FONT_STYLE_INHERIT,
CSS_FONT_VARIANT_INHERIT,
{ CSS_HEIGHT_AUTO, { 1, CSS_UNIT_EM } },
{ CSS_LINE_HEIGHT_INHERIT, { 1.3 } },
{ { CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_MARGIN_LENGTH, { { 0, CSS_UNIT_PX } } } },
{ { CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } },
{ CSS_PADDING_LENGTH, { { 0, CSS_UNIT_PX } } } },
CSS_TEXT_ALIGN_INHERIT,
CSS_TEXT_DECORATION_INHERIT,
{ CSS_TEXT_INDENT_INHERIT, { { 0, CSS_UNIT_EM } } },
CSS_TEXT_TRANSFORM_INHERIT,
CSS_VISIBILITY_INHERIT,
{ CSS_WIDTH_AUTO, { { 1, CSS_UNIT_EM } } },
CSS_WHITE_SPACE_INHERIT
};
/**
* Convert a CONTENT_CSS for use.
*/
int css_convert(struct content *c, unsigned int width, unsigned int height)
{
unsigned char *source_data;
unsigned char *current, *end, *token_text;
unsigned int i;
int token;
void *parser;
struct css_parser_params param = {false, c, 0, false, false};
struct css_parser_token token_data;
c->data.css.css = malloc(sizeof *c->data.css.css);
parser = css_parser_Alloc(malloc);
source_data = realloc(c->source_data, c->source_size + 10);
if (!c->data.css.css || !parser || !source_data) {
free(c->data.css.css);
css_parser_Free(parser, free);
return 1;
}
for (i = 0; i != HASH_SIZE; i++)
c->data.css.css->rule[i] = 0;
c->data.css.import_count = 0;
c->data.css.import_url = 0;
c->data.css.import_content = 0;
c->active = 0;
c->source_data = source_data;
for (i = 0; i != 10; i++)
source_data[c->source_size + i] = 0;
current = source_data;
end = source_data + c->source_size;
while (current < end && (token = css_tokenise(&current, end + 10,
&token_text))) {
token_data.text = token_text;
token_data.length = current - token_text;
css_parser_(parser, token, token_data, &param);
if (param.syntax_error) {
LOG(("syntax error near offset %i",
token_text - source_data));
param.syntax_error = false;
} else if (param.memory_error) {
LOG(("out of memory"));
break;
}
}
css_parser_(parser, 0, token_data, &param);
css_parser_Free(parser, free);
if (param.memory_error)
return 1;
/*css_dump_stylesheet(c->data.css.css);*/
/* complete fetch of any imported stylesheets */
while (c->active != 0) {
LOG(("importing %i from '%s'", c->active, c->url));
fetch_poll();
gui_multitask();
}
c->status = CONTENT_STATUS_DONE;
return 0;
}
void css_revive(struct content *c, unsigned int width, unsigned int height)
{
unsigned int i;
/* imported stylesheets */
for (i = 0; i != c->data.css.import_count; i++) {
c->data.css.import_content[i] = fetchcache(
c->data.css.import_url[i], c->url,
css_atimport_callback, c, (void*)i,
c->width, c->height, true
#ifdef WITH_POST
, 0, 0
#endif
#ifdef WITH_COOKIES
, false
#endif
);
if (c->data.css.import_content[i] == 0)
continue;
if (c->data.css.import_content[i]->status != CONTENT_STATUS_DONE)
c->active++;
}
while (c->active != 0) {
fetch_poll();
gui_multitask();
}
}
/**
* Destroy a CONTENT_CSS and free all resources it owns.
*/
void css_destroy(struct content *c)
{
unsigned int i;
struct css_selector *r;
for (i = 0; i != HASH_SIZE; i++) {
for (r = c->data.css.css->rule[i]; r != 0; r = r->next)
free(r->style);
css_free_selector(c->data.css.css->rule[i]);
}
free(c->data.css.css);
/* imported stylesheets */
for (i = 0; i != c->data.css.import_count; i++)
if (c->data.css.import_content[i] != 0) {
free(c->data.css.import_url[i]);
content_remove_user(c->data.css.import_content[i],
css_atimport_callback, c, (void*)i);
}
free(c->data.css.import_url);
free(c->data.css.import_content);
}
/**
* Create a new struct css_node.
*
* \param type type of node
* \param data string for data, not copied
* \param data_length length of data
* \return allocated node, or 0 if memory exhausted
*
* Used by the parser.
*/
struct css_node * css_new_node(css_node_type type,
const char *data, unsigned int data_length)
{
struct css_node *node = malloc(sizeof *node);
if (!node)
return 0;
node->type = type;
node->data = data;
node->data_length = data_length;
node->value = 0;
node->next = 0;
node->comb = CSS_COMB_NONE;
node->style = 0;
node->specificity = 0;
return node;
}
/**
* Free a struct css_node recursively.
*
* \param node css_node to free
*
* Used by the parser.
*/
void css_free_node(struct css_node *node)
{
if (!node)
return;
if (node->value)
css_free_node(node->value);
if (node->next)
css_free_node(node->next);
free(node);
}
/**
* Create a new struct css_selector.
*
* \param type type of selector
* \param data string for data, not copied
* \param data_length length of data
* \return allocated selector, or 0 if memory exhausted
*/
struct css_selector * css_new_selector(css_selector_type type,
const char *data, unsigned int data_length)
{
struct css_selector *node = malloc(sizeof *node);
if (!node)
return 0;
node->type = type;
node->data = data;
node->data_length = data_length;
node->data2 = 0;
node->detail = 0;
node->combiner = 0;
node->next = 0;
node->comb = CSS_COMB_NONE;
node->style = 0;
node->specificity = 0;
return node;
}
/**
* Free a struct css_selector recursively.
*
* \param node css_selector to free
*/
void css_free_selector(struct css_selector *node)
{
if (!node)
return;
if (node->detail)
css_free_selector(node->detail);
if (node->combiner)
css_free_selector(node->combiner);
if (node->next)
css_free_selector(node->next);
free(node);
}
/**
* Process an \@import rule.
*/
void css_atimport(struct content *c, struct css_node *node)
{
const char *s;
char *t, *url, *url1;
bool string = false, screen = true;
unsigned int i;
char **import_url;
struct content **import_content;
LOG(("@import rule"));
import_url = realloc(c->data.css.import_url,
(c->data.css.import_count + 1) *
sizeof(*c->data.css.import_url));
if (!import_url) {
/** \todo report to user */
return;
}
c->data.css.import_url = import_url;
import_content = realloc(c->data.css.import_content,
(c->data.css.import_count + 1) *
sizeof(*c->data.css.import_content));
if (!import_content) {
/** \todo report to user */
return;
}
c->data.css.import_content = import_content;
/* uri(...) or "..." */
switch (node->type) {
case CSS_NODE_URI:
LOG(("URI '%.*s'", node->data_length, node->data));
for (s = node->data + 4;
*s == ' ' || *s == '\t' || *s == '\r' ||
*s == '\n' || *s == '\f';
s++)
;
if (*s == '\'' || *s == '"') {
string = true;
s++;
}
url = strndup(s, node->data_length - (s - node->data));
if (!url) {
/** \todo report to user */
return;
}
for (t = url + strlen(url) - 2;
*t == ' ' || *t == '\t' || *t == '\r' ||
*t == '\n' || *t == '\f';
t--)
;
if (string)
*t = 0;
else
*(t + 1) = 0;
break;
case CSS_NODE_STRING:
LOG(("STRING '%.*s'", node->data_length, node->data));
url = strndup(node->data, node->data_length);
if (!url) {
/** \todo report to user */
return;
}
break;
default:
return;
}
/* media not specified, 'screen', or 'all' */
for (node = node->next; node != 0; node = node->next) {
screen = false;
if (node->type != CSS_NODE_IDENT) {
free(url);
return;
}
LOG(("medium '%s'", node->data));
if ((node->data_length == 6 &&
strncmp(node->data, "screen", 6) == 0) ||
(node->data_length == 3 &&
strncmp(node->data, "all", 3) == 0)) {
screen = true;
break;
}
node = node->next;
if (node == 0 || node->type != CSS_NODE_COMMA) {
free(url);
return;
}
}
if (!screen) {
free(url);
return;
}
url1 = url_join(url, c->url);
if (!url1) {
free(url);
return;
}
/* start the fetch */
c->data.css.import_count++;
i = c->data.css.import_count - 1;
c->data.css.import_url[i] = url1;
c->data.css.import_content[i] = fetchcache(
c->data.css.import_url[i], c->url, css_atimport_callback,
c, (void*)i, c->width, c->height, true
#ifdef WITH_POST
, 0, 0
#endif
#ifdef WITH_COOKIES
, false
#endif
);
if (c->data.css.import_content[i] &&
c->data.css.import_content[i]->status != CONTENT_STATUS_DONE)
c->active++;
free(url);
}
/**
* Fetchcache callback for imported stylesheets.
*/
void css_atimport_callback(content_msg msg, struct content *css,
void *p1, void *p2, union content_msg_data data)
{
struct content *c = p1;
unsigned int i = (unsigned int) p2;
switch (msg) {
case CONTENT_MSG_LOADING:
if (css->type != CONTENT_CSS) {
content_remove_user(css, css_atimport_callback, c, (void*)i);
c->data.css.import_content[i] = 0;
c->active--;
c->error = 1;
}
break;
case CONTENT_MSG_READY:
break;
case CONTENT_MSG_DONE:
LOG(("got imported stylesheet '%s'", css->url));
/*css_dump_stylesheet(css->data.css);*/
c->active--;
break;
case CONTENT_MSG_ERROR:
c->data.css.import_content[i] = 0;
c->active--;
c->error = 1;
break;
case CONTENT_MSG_STATUS:
break;
case CONTENT_MSG_REDIRECT:
c->active--;
free(c->data.css.import_url[i]);
c->data.css.import_url[i] = strdup(data.redirect);
if (!c->data.css.import_url[i]) {
/** \todo report to user */
c->error = 1;
return;
}
c->data.css.import_content[i] = fetchcache(
c->data.css.import_url[i], c->url, css_atimport_callback,
c, (void*)i, css->width, css->height, true
#ifdef WITH_POST
, 0, 0
#endif
#ifdef WITH_COOKIES
, false
#endif
);
if (c->data.css.import_content[i] &&
c->data.css.import_content[i]->status != CONTENT_STATUS_DONE)
c->active++;
break;
default:
assert(0);
}
}
/**
* Find the style which applies to an element.
*
* \param css content of type CONTENT_CSS
* \param element element in xml tree to match
* \param style style to update
*
* The style is updated with any rules that match the element.
*/
void css_get_style(struct content *css, xmlNode *element,
struct css_style *style)
{
struct css_stylesheet *stylesheet = css->data.css.css;
struct css_selector *rule;
unsigned int hash, i;
/* imported stylesheets */
for (i = 0; i != css->data.css.import_count; i++)
if (css->data.css.import_content[i] != 0)
css_get_style(css->data.css.import_content[i],
element, style);
/* match rules which end with the same element */
hash = css_hash((const char *) element->name,
strlen((const char *) element->name));
for (rule = stylesheet->rule[hash]; rule; rule = rule->next)
if (css_match_rule(rule, element))
css_merge(style, rule->style);
/* match rules which apply to all elements */
for (rule = stylesheet->rule[0]; rule; rule = rule->next)
if (css_match_rule(rule, element))
css_merge(style, rule->style);
}
/**
* Determine if a rule applies to an element.
*/
bool css_match_rule(struct css_selector *rule, xmlNode *element)
{
struct css_selector *detail;
xmlNode *anc, *prev;
assert(element->type == XML_ELEMENT_NODE);
if (rule->data && (rule->data_length !=
strlen((const char *) element->name) ||
strncasecmp(rule->data, (const char *) element->name,
rule->data_length) != 0))
return false;
for (detail = rule->detail; detail; detail = detail->next) {
if (!css_match_detail(detail, element))
return false;
}
if (!rule->combiner)
return true;
switch (rule->comb) {
case CSS_COMB_ANCESTOR:
for (anc = element->parent; anc; anc = anc->parent)
if (anc->type == XML_ELEMENT_NODE &&
css_match_rule(rule->combiner, anc))
return true;
break;
case CSS_COMB_PRECEDED:
for (prev = element->prev;
prev && prev->type != XML_ELEMENT_NODE;
prev = prev->prev)
;
if (!prev)
return false;
return css_match_rule(rule->combiner, prev);
break;
case CSS_COMB_PARENT:
for (anc = element->parent;
anc && anc->type != XML_ELEMENT_NODE;
anc = anc->parent)
;
if (!anc)
return false;
return css_match_rule(rule->combiner, anc);
break;
default:
assert(0);
}
return false;
}
/**
* Determine if a selector detail matches an element.
*
* \param detail a css_selector of type other than CSS_SELECTOR_ELEMENT
* \param element element in xml tree to match
* \return true if the selector matches the element
*/
bool css_match_detail(const struct css_selector *detail,
xmlNode *element)
{
bool match = false;
char *s = 0;
char *space, *word;
unsigned int length;
switch (detail->type) {
case CSS_SELECTOR_ID:
s = (char *) xmlGetProp(element,
(const xmlChar *) "id");
if (s && strlen(s) == detail->data_length &&
strncasecmp(detail->data, s,
detail->data_length) == 0)
match = true;
break;
case CSS_SELECTOR_CLASS:
s = (char *) xmlGetProp(element,
(const xmlChar *) "class");
if (!s)
break;
word = s;
do {
space = strchr(word, ' ');
if (space)
length = space - word;
else
length = strlen(word);
if (length == detail->data_length &&
strncasecmp(word, detail->data,
length) == 0) {
match = true;
break;
}
word = space + 1;
} while (space);
break;
case CSS_SELECTOR_ATTRIB:
/* matches if an attribute is present */
word = strndup(detail->data, detail->data_length);
if (!word) {
/** \todo report to user */
return false;
}
s = (char *) xmlGetProp(element,
(const xmlChar *) word);
free(word);
if (s)
match = true;
break;
case CSS_SELECTOR_ATTRIB_EQ:
/* matches if an attribute has a certain value*/
word = strndup(detail->data, detail->data_length);
if (!word) {
/** \todo report to user */
return false;
}
s = (char *) xmlGetProp(element,
(const xmlChar *) word);
free(word);
if (s && strlen(s) == detail->data2_length &&
strncasecmp(detail->data2, s,
detail->data2_length) == 0)
match = true;
break;
case CSS_SELECTOR_ATTRIB_INC:
/* matches if one of the space separated words
* in the attribute is equal */
word = strndup(detail->data,
detail->data_length);
if (!word) {
/** \todo report to user */
return false;
}
s = (char *) xmlGetProp(element,
(const xmlChar *) word);
free(word);
if (!s)
break;
word = s;
do {
space = strchr(word, ' ');
if (space)
length = space - word;
else
length = strlen(word);
if (length == detail->data2_length &&
strncasecmp(word, detail->data2,
length) == 0) {
match = true;
break;
}
word = space + 1;
} while (space);
break;
case CSS_SELECTOR_ATTRIB_DM:
/* matches if a prefix up to a hyphen matches */
word = strndup(detail->data,
detail->data_length);
if (!word) {
/** \todo report to user */
return false;
}
s = (char *) xmlGetProp(element,
(const xmlChar *) word);
free(word);
if (!s)
break;
length = detail->data2_length;
if (strncasecmp(detail->data2, s, length) == 0 &&
(s[length] == '-' || s[length] == 0))
match = true;
break;
case CSS_SELECTOR_PSEUDO:
break;
default:
assert(0);
}
if (s)
xmlFree(s);
return match;
}
/**
* Parse a stand-alone CSS property list.
*
* \param style css_style to update
* \param str property list, as found in HTML style attributes
*/
void css_parse_property_list(struct css_style * style, char * str)
{
unsigned char *source_data;
unsigned char *current, *end, *token_text;
size_t length;
unsigned int i;
int token;
void *parser;
struct css_parser_params param = {true, 0, 0, false, false};
struct css_parser_token token_data;
const struct css_parser_token token_start = { "{", 1 };
const struct css_parser_token token_end = { "}", 1 };
length = strlen(str);
parser = css_parser_Alloc(malloc);
source_data = malloc(length + 10);
if (!parser || !source_data) {
free(parser);
css_parser_Free(parser, free);
return;
}
strcpy(source_data, str);
for (i = 0; i != 10; i++)
source_data[length + i] = 0;
css_parser_(parser, LBRACE, token_start, &param);
current = source_data;
end = source_data + strlen(str);
while (current < end && (token = css_tokenise(&current, end + 10,
&token_text))) {
token_data.text = token_text;
token_data.length = current - token_text;
css_parser_(parser, token, token_data, &param);
if (param.syntax_error) {
LOG(("syntax error near offset %i",
token_text - source_data));
param.syntax_error = false;
} else if (param.memory_error) {
LOG(("out of memory"));
break;
}
}
css_parser_(parser, RBRACE, token_end, &param);
css_parser_(parser, 0, token_data, &param);
css_parser_Free(parser, free);
if (param.memory_error) {
css_free_node(param.declaration);
return;
}
css_add_declarations(style, param.declaration);
css_free_node(param.declaration);
free(source_data);
}
/**
* Dump a css_style to stderr in CSS-like syntax.
*/
void css_dump_style(const struct css_style * const style)
{
unsigned int i;
fprintf(stderr, "{ ");
#define DUMP_COLOR(z, s) \
if (style->z != css_empty_style.z) { \
if (style->z == TRANSPARENT) \
fprintf(stderr, s ": transparent; "); \
else if (style->z == CSS_COLOR_NONE) \
fprintf(stderr, s ": none; "); \
else \
fprintf(stderr, s ": #%.6lx; ", style->z); \
}
#define DUMP_KEYWORD(z, s, n) \
if (style->z != css_empty_style.z) \
fprintf(stderr, s ": %s; ", n[style->z]);
DUMP_COLOR(background_color, "background-color");
DUMP_KEYWORD(clear, "clear", css_clear_name);
DUMP_COLOR(color, "color");
DUMP_KEYWORD(cursor, "cursor", css_cursor_name);
DUMP_KEYWORD(display, "display", css_display_name);
DUMP_KEYWORD(float_, "float", css_float_name);
if (style->font_style != css_empty_style.font_style ||
style->font_weight != css_empty_style.font_weight ||
style->font_size.size !=
css_empty_style.font_size.size ||
style->line_height.size !=
css_empty_style.line_height.size ||
style->font_family != css_empty_style.font_family ||
style->font_variant != css_empty_style.font_variant) {
fprintf(stderr, "font: %s %s ",
css_font_style_name[style->font_style],
css_font_weight_name[style->font_weight]);
switch (style->font_size.size) {
case CSS_FONT_SIZE_ABSOLUTE:
fprintf(stderr, "[%g]",
style->font_size.value.absolute);
break;
case CSS_FONT_SIZE_LENGTH:
css_dump_length(&style->font_size.value.length);
break;
case CSS_FONT_SIZE_PERCENT:
fprintf(stderr, "%g%%",
style->font_size.value.percent);
break;
case CSS_FONT_SIZE_INHERIT:
fprintf(stderr, "inherit");
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
fprintf(stderr, "/");
switch (style->line_height.size) {
case CSS_LINE_HEIGHT_ABSOLUTE:
fprintf(stderr, "[%g]",
style->line_height.value.absolute);
break;
case CSS_LINE_HEIGHT_LENGTH:
css_dump_length(&style->line_height.value.length);
break;
case CSS_LINE_HEIGHT_PERCENT:
fprintf(stderr, "%g%%",
style->line_height.value.percent);
break;
case CSS_LINE_HEIGHT_INHERIT:
fprintf(stderr, "inherit");
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
fprintf(stderr, " %s",
css_font_family_name[style->font_family]);
fprintf(stderr, " %s",
css_font_variant_name[style->font_variant]);
fprintf(stderr, "; ");
}
if (style->height.height != css_empty_style.height.height) {
fprintf(stderr, "height: ");
switch (style->height.height) {
case CSS_HEIGHT_AUTO:
fprintf(stderr, "auto"); break;
case CSS_HEIGHT_LENGTH:
css_dump_length(&style->height.length); break;
default:
fprintf(stderr, "UNKNOWN"); break;
}
fprintf(stderr, "; ");
}
if (style->margin[0].margin != css_empty_style.margin[0].margin ||
style->margin[1].margin != css_empty_style.margin[1].margin ||
style->margin[2].margin != css_empty_style.margin[2].margin ||
style->margin[3].margin != css_empty_style.margin[3].margin) {
fprintf(stderr, "margin:");
for (i = 0; i != 4; i++) {
switch (style->margin[i].margin) {
case CSS_MARGIN_INHERIT:
fprintf(stderr, " inherit");
break;
case CSS_MARGIN_LENGTH:
fprintf(stderr, " ");
css_dump_length(&style->margin[i].value.length);
break;
case CSS_MARGIN_PERCENT:
fprintf(stderr, " %g%%",
style->margin[i].value.percent);
break;
case CSS_MARGIN_AUTO:
fprintf(stderr, " auto");
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
}
fprintf(stderr, "; ");
}
if (style->padding[0].padding != css_empty_style.padding[0].padding ||
style->padding[1].padding != css_empty_style.padding[1].padding ||
style->padding[2].padding != css_empty_style.padding[2].padding ||
style->padding[3].padding != css_empty_style.padding[3].padding) {
fprintf(stderr, "padding:");
for (i = 0; i != 4; i++) {
switch (style->padding[i].padding) {
case CSS_PADDING_INHERIT:
fprintf(stderr, " inherit");
break;
case CSS_PADDING_LENGTH:
fprintf(stderr, " ");
css_dump_length(&style->padding[i].value.length);
break;
case CSS_PADDING_PERCENT:
fprintf(stderr, " %g%%",
style->padding[i].value.percent);
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
}
fprintf(stderr, "; ");
}
DUMP_KEYWORD(text_align, "text-align", css_text_align_name);
if (style->text_decoration != css_empty_style.text_decoration) {
fprintf(stderr, "text-decoration:");
if (style->text_decoration == CSS_TEXT_DECORATION_NONE)
fprintf(stderr, " none");
if (style->text_decoration == CSS_TEXT_DECORATION_INHERIT)
fprintf(stderr, " inherit");
if (style->text_decoration & CSS_TEXT_DECORATION_UNDERLINE)
fprintf(stderr, " underline");
if (style->text_decoration & CSS_TEXT_DECORATION_OVERLINE)
fprintf(stderr, " overline");
if (style->text_decoration & CSS_TEXT_DECORATION_LINE_THROUGH)
fprintf(stderr, " line-through");
if (style->text_decoration & CSS_TEXT_DECORATION_BLINK)
fprintf(stderr, " blink");
fprintf(stderr, "; ");
}
if (style->text_indent.size != css_empty_style.text_indent.size) {
fprintf(stderr, "text-indent: ");
switch (style->text_indent.size) {
case CSS_TEXT_INDENT_LENGTH:
css_dump_length(&style->text_indent.value.length);
break;
case CSS_TEXT_INDENT_PERCENT:
fprintf(stderr, "%g%%",
style->text_indent.value.percent);
break;
case CSS_TEXT_INDENT_INHERIT:
fprintf(stderr, "inherit");
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
fprintf(stderr, "; ");
}
DUMP_KEYWORD(text_transform, "text-transform", css_text_transform_name);
DUMP_KEYWORD(visibility, "visibility", css_visibility_name);
if (style->width.width != css_empty_style.width.width) {
fprintf(stderr, "width: ");
switch (style->width.width) {
case CSS_WIDTH_INHERIT:
fprintf(stderr, "inherit");
break;
case CSS_WIDTH_AUTO:
fprintf(stderr, "auto");
break;
case CSS_WIDTH_LENGTH:
css_dump_length(&style->width.value.length);
break;
case CSS_WIDTH_PERCENT:
fprintf(stderr, "%g%%",
style->width.value.percent);
break;
default:
fprintf(stderr, "UNKNOWN");
break;
}
fprintf(stderr, "; ");
}
DUMP_KEYWORD(white_space, "white-space", css_white_space_name);
fprintf(stderr, "}");
}
/**
* Dump a css_length to stderr.
*/
void css_dump_length(const struct css_length * const length)
{
fprintf(stderr, "%g%s", length->value, css_unit_name[length->unit]);
}
/**
* Dump a complete css_stylesheet to stderr in CSS syntax.
*/
void css_dump_stylesheet(const struct css_stylesheet * stylesheet)
{
unsigned int i;
struct css_selector *r;
for (i = 0; i != HASH_SIZE; i++) {
/*fprintf(stderr, "hash %i:\n", i);*/
for (r = stylesheet->rule[i]; r != 0; r = r->next) {
css_dump_selector(r);
fprintf(stderr, " <%lx> ", r->specificity);
css_dump_style(r->style);
fprintf(stderr, "\n");
}
}
}
/**
* Dump a css_selector to stderr in CSS syntax.
*/
void css_dump_selector(const struct css_selector *r)
{
struct css_selector *m;
if (r->combiner)
css_dump_selector(r->combiner);
switch (r->comb) {
case CSS_COMB_NONE: break;
case CSS_COMB_ANCESTOR: fprintf(stderr, " "); break;
case CSS_COMB_PARENT: fprintf(stderr, " > "); break;
case CSS_COMB_PRECEDED: fprintf(stderr, " + "); break;
}
if (r->data)
fprintf(stderr, "%.*s", r->data_length, r->data);
else
fprintf(stderr, "*");
for (m = r->detail; m; m = m->next) {
switch (m->type) {
case CSS_SELECTOR_ID:
fprintf(stderr, "#%.*s",
m->data_length, m->data);
break;
case CSS_SELECTOR_CLASS:
fprintf(stderr, ".%.*s",
m->data_length, m->data);
break;
case CSS_SELECTOR_ATTRIB:
fprintf(stderr, "[%.*s]",
m->data_length, m->data);
break;
case CSS_SELECTOR_ATTRIB_EQ:
fprintf(stderr, "[%.*s=%.*s]",
m->data_length, m->data,
m->data2_length, m->data2);
break;
case CSS_SELECTOR_ATTRIB_INC:
fprintf(stderr, "[%.*s~=%.*s]",
m->data_length, m->data,
m->data2_length, m->data2);
break;
case CSS_SELECTOR_ATTRIB_DM:
fprintf(stderr, "[%.*s|=%.*s]",
m->data_length, m->data,
m->data2_length, m->data2);
break;
case CSS_SELECTOR_PSEUDO:
fprintf(stderr, ":%.*s",
m->data_length, m->data);
break;
default:
fprintf(stderr, "(unexpected detail)");
}
}
}
/**
* Cascade styles.
*
* \param style css_style to modify
* \param apply css_style to cascade onto style
*
* Attributes which have the value 'inherit' in apply are unchanged in style.
* Other attributes are copied to style, calculating percentages relative to
* style where applicable.
*/
void css_cascade(struct css_style * const style,
const struct css_style * const apply)
{
unsigned int i;
float f;
/* text-decoration: approximate CSS 2.1 by inheriting into inline elements */
if (apply->text_decoration != CSS_TEXT_DECORATION_INHERIT)
style->text_decoration = apply->text_decoration;
/* if (style->display == CSS_DISPLAY_INLINE && apply->display != CSS_DISPLAY_INLINE)
style->text_decoration = CSS_TEXT_DECORATION_NONE;*/
if (apply->background_color != CSS_COLOR_INHERIT)
style->background_color = apply->background_color;
if (apply->clear != CSS_CLEAR_INHERIT)
style->clear = apply->clear;
if (apply->color != CSS_COLOR_INHERIT)
style->color = apply->color;
if (apply->cursor != CSS_CURSOR_INHERIT)
style->cursor = apply->cursor;
if (apply->display != CSS_DISPLAY_INHERIT)
style->display = apply->display;
if (apply->float_ != CSS_FLOAT_INHERIT)
style->float_ = apply->float_;
if (apply->font_family != CSS_FONT_FAMILY_INHERIT)
style->font_family = apply->font_family;
if (apply->font_style != CSS_FONT_STYLE_INHERIT)
style->font_style = apply->font_style;
if (apply->font_weight != CSS_FONT_WEIGHT_INHERIT)
style->font_weight = apply->font_weight;
if (apply->font_variant != CSS_FONT_VARIANT_INHERIT)
style->font_variant = apply->font_variant;
if (apply->height.height != CSS_HEIGHT_INHERIT)
style->height = apply->height;
if (apply->line_height.size != CSS_LINE_HEIGHT_INHERIT)
style->line_height = apply->line_height;
if (apply->text_align != CSS_TEXT_ALIGN_INHERIT)
style->text_align = apply->text_align;
if (apply->text_indent.size != CSS_TEXT_INDENT_INHERIT)
style->text_indent = apply->text_indent;
if (apply->text_transform != CSS_TEXT_TRANSFORM_INHERIT)
style->text_transform = apply->text_transform;
if (apply->visibility != CSS_VISIBILITY_INHERIT)
style->visibility = apply->visibility;
if (apply->width.width != CSS_WIDTH_INHERIT)
style->width = apply->width;
if (apply->white_space != CSS_WHITE_SPACE_INHERIT)
style->white_space = apply->white_space;
/* font-size */
f = apply->font_size.value.percent / 100;
switch (apply->font_size.size) {
case CSS_FONT_SIZE_ABSOLUTE:
style->font_size = apply->font_size;
break;
case CSS_FONT_SIZE_LENGTH:
switch (apply->font_size.value.length.unit) {
case CSS_UNIT_EM:
f = apply->font_size.value.length.value;
break;
case CSS_UNIT_EX:
f = apply->font_size.value.length.value * 0.6 /*?*/;
break;
default:
style->font_size = apply->font_size;
}
if ((apply->font_size.value.length.unit != CSS_UNIT_EM) &&
(apply->font_size.value.length.unit != CSS_UNIT_EX))
break;
/* drop through if EM or EX */
case CSS_FONT_SIZE_PERCENT:
switch (style->font_size.size) {
case CSS_FONT_SIZE_ABSOLUTE:
style->font_size.value.absolute *= f;
break;
case CSS_FONT_SIZE_LENGTH:
style->font_size.value.length.value *= f;
break;
default:
die("attempting percentage of unknown font-size");
}
break;
case CSS_FONT_SIZE_INHERIT:
default: /* leave unchanged */
break;
}
for (i = 0; i != 4; i++) {
if (apply->border[i].color != CSS_COLOR_INHERIT)
style->border[i].color = apply->border[i].color;
if (apply->border[i].width.width != CSS_BORDER_WIDTH_INHERIT)
style->border[i].width = apply->border[i].width;
if (apply->border[i].style != CSS_BORDER_STYLE_INHERIT)
style->border[i].style = apply->border[i].style;
if (apply->margin[i].margin != CSS_MARGIN_INHERIT)
style->margin[i] = apply->margin[i];
if (apply->padding[i].padding != CSS_PADDING_INHERIT)
style->padding[i] = apply->padding[i];
}
}
/**
* Merge styles.
*
* \param style css_style to modify
* \param apply css_style to merge onto style
*
* Attributes which have the value 'inherit' in apply are unchanged in style.
* Other attributes are copied to style, overwriting it.
*/
void css_merge(struct css_style * const style,
const struct css_style * const apply)
{
unsigned int i;
if (apply->background_color != CSS_COLOR_INHERIT)
style->background_color = apply->background_color;
if (apply->clear != CSS_CLEAR_INHERIT)
style->clear = apply->clear;
if (apply->color != CSS_COLOR_INHERIT)
style->color = apply->color;
if (apply->cursor != CSS_CURSOR_INHERIT)
style->cursor = apply->cursor;
if (apply->display != CSS_DISPLAY_INHERIT)
style->display = apply->display;
if (apply->float_ != CSS_FLOAT_INHERIT)
style->float_ = apply->float_;
if (apply->font_family != CSS_FONT_FAMILY_INHERIT)
style->font_family = apply->font_family;
if (apply->font_size.size != CSS_FONT_SIZE_INHERIT)
style->font_size = apply->font_size;
if (apply->font_style != CSS_FONT_STYLE_INHERIT)
style->font_style = apply->font_style;
if (apply->font_weight != CSS_FONT_WEIGHT_INHERIT)
style->font_weight = apply->font_weight;
if (apply->font_variant != CSS_FONT_VARIANT_INHERIT)
style->font_variant = apply->font_variant;
if (apply->height.height != CSS_HEIGHT_INHERIT)
style->height = apply->height;
if (apply->line_height.size != CSS_LINE_HEIGHT_INHERIT)
style->line_height = apply->line_height;
if (apply->text_align != CSS_TEXT_ALIGN_INHERIT)
style->text_align = apply->text_align;
if (apply->text_decoration != CSS_TEXT_DECORATION_INHERIT)
style->text_decoration = apply->text_decoration;
if (apply->text_indent.size != CSS_TEXT_INDENT_INHERIT)
style->text_indent = apply->text_indent;
if (apply->text_transform != CSS_TEXT_TRANSFORM_INHERIT)
style->text_transform = apply->text_transform;
if (apply->visibility != CSS_VISIBILITY_INHERIT)
style->visibility = apply->visibility;
if (apply->width.width != CSS_WIDTH_INHERIT)
style->width = apply->width;
if (apply->white_space != CSS_WHITE_SPACE_INHERIT)
style->white_space = apply->white_space;
for (i = 0; i != 4; i++) {
if (apply->border[i].color != CSS_COLOR_INHERIT)
style->border[i].color = apply->border[i].color;
if (apply->border[i].width.width != CSS_BORDER_WIDTH_INHERIT)
style->border[i].width = apply->border[i].width;
if (apply->border[i].style != CSS_BORDER_STYLE_INHERIT)
style->border[i].style = apply->border[i].style;
if (apply->margin[i].margin != CSS_MARGIN_INHERIT)
style->margin[i] = apply->margin[i];
if (apply->padding[i].padding != CSS_PADDING_INHERIT)
style->padding[i] = apply->padding[i];
}
}
/**
* Calculate a hash for an element name.
*
* The hash is case-insensitive.
*/
unsigned int css_hash(const char *s, int length)
{
int i;
unsigned int z = 0;
if (s == 0)
return 0;
for (i = 0; i != length; i++)
z += s[i] & 0x1f; /* lower 5 bits, case insensitive */
return (z % (HASH_SIZE - 1)) + 1;
}
/**
* Convert a struct css_length to pixels.
*/
float len(struct css_length * length, struct css_style * style)
{
assert(!((length->unit == CSS_UNIT_EM || length->unit == CSS_UNIT_EX) && style == 0));
switch (length->unit) {
case CSS_UNIT_EM: return length->value * len(&style->font_size.value.length, 0);
case CSS_UNIT_EX: return length->value * len(&style->font_size.value.length, 0) * 0.6;
case CSS_UNIT_PX: return length->value;
case CSS_UNIT_IN: return length->value * 90.0;
case CSS_UNIT_CM: return length->value * 35.0;
case CSS_UNIT_MM: return length->value * 3.5;
case CSS_UNIT_PT: return length->value * 90.0 / 72.0;
case CSS_UNIT_PC: return length->value * 90.0 / 6.0;
default: break;
}
return 0;
}
#ifdef DEBUG
int main()
{
const char data[] = "h1 { blah: foo; display: block; }"
"h1.c1 h2#id1 + h3, h4 h5.c2#id2 { size: 100mm; color: red }"
"p { background-color: #123; clear: left; color: #ff0000; display: block;"
"float: left; font-size: 150%; height: blah; line-height: 100;"
"text-align: left right; width: 90%;}";
struct content c;
css_create(&c);
css_process_data(&c, data, 24);
css_process_data(&c, data + 24, sizeof(data) - 25);
css_convert(&c, 100, 100);
return 0;
}
#endif