/**
* Read the next rule from the input data
* @param data the CSS data to read from
* @param offset VAR param of the offset into data to read from
* @return the rule or NULL
*/
static css_rule *get_css_rule( const char *data, int *offset )
{
int pos = *offset;
int state = 0;
int bodyStart=-1,bodyEnd=-1;
css_rule *rule = NULL;
while ( state >= 0 && data[pos] != 0 )
{
switch ( state )
{
case 0: // collecting selector
if ( data[pos] == '{' )
{
bodyStart = pos;
state = 1;
}
pos++;
break;
case 1: // collecting body
if ( data[pos] == '}' )
{
bodyEnd = pos;
state = -1;
}
pos++;
break;
}
}
if ( (bodyStart == -1 || bodyEnd == -1)&&state!=0 )
{
warning("failed to find css rule body", 0 );
return NULL;
}
else
{
rule = css_rule_create();
if ( rule != NULL )
{
int res = get_selectors( data, *offset, bodyStart-(*offset), rule );
if ( res )
res = get_properties( &data[bodyStart+1], (bodyEnd-bodyStart),
rule );
}
// update pos even if rule-reading fails
*offset = pos;
if ( css_rule_valid(rule) )
return rule;
else if ( rule != NULL )
css_rule_dispose( rule );
return NULL;
}
}
/* TODO: add more error checks, cut corner cases */
int css_parse(css_parser *state, const char *data, int len) {
#define CHANGE_BUFFER(BUFF) \
state->tobuf = (BUFF); \
*(state->tobuf) = 0; \
state->tobuf_space = sizeof((BUFF))
#define OUTER_SPACE 0 /* whitespace outside the ___sel{}___ */
#define INNER_SPACE 9 /* whitespace inside the {___prop:val;___} */
#define MIDDLE_SPACE 8 /* whitespace between prop:____val */
#define COMMENT 1
#define SUBSTRING 5
#define SELECTORS 3
#define PROPERTY 6
#define VALUE 7
int i, j;
#if 0
printf("\n");//debug
printf("BUF2>> %s[end]\n", state->selector_buffer);
printf("BUF3>> %s[end]\n", state->property_buffer);
printf("BUF4>> %s[end]\n", state->value_buffer);
#endif
for (i = 0; i < len; i++) {
char c = data[i];
//printf("[%d] -- %c\n", sector, c);
//if ( c == '\n' || c == '\r' || c == '\t') continue;
if (isspace(c)) {
if (state->sector == OUTER_SPACE) continue; /* ignore outer whitespace */
if (state->sector == PROPERTY) continue; /* ignore whitespace in property names -- note, not clean, might lead to errors */
if (state->sector == INNER_SPACE) continue; /* ignore whitespace after property values */
if (state->sector == MIDDLE_SPACE) continue; /* ignore whitespace inside rule blocks? */
}
if (c == '/' && state->sector == COMMENT) { /* end of comment */
/* pop sector */
state->sector = state->prev_sector;
state->prev_sector = 0;
continue;
}
if (state->sector == COMMENT) { /* inside a comment, ignore */
continue;
}
if (c == '/') { /* start of comment */
/* push sector */
state->prev_sector = state->sector;
state->sector = COMMENT;
continue;
}
if (c == 0) break; /* not readable */
if (c == ',') { /* end of selector? */
if (state->sector == SELECTORS) {
//printf("Got selector %d: `%s`\n", num_selectors, buf2);
state->selectors[state->num_selectors++] = css_target_parse(state->selector_buffer);
CHANGE_BUFFER(state->selector_buffer);
state->sector = OUTER_SPACE;
continue;
}
}
if (c == '{') { /* start of rule block? */
if (state->sector == SELECTORS) {
//printf("Got last selector: `%s`\n", buf2);
state->selectors[state->num_selectors++] = css_target_parse(state->selector_buffer);
CHANGE_BUFFER(state->selector_buffer);
}
/* now, create empty rules for each selector */
for (j = 0; j < state->num_selectors; j++) {
state->rules[j] = css_rule_create(state->selectors[j], NULL, NULL);
state->num_rules++;
if (!state->style) state->style = state->rules[j];
else css_rule_add_next(state->style, state->rules[j]);
}
/* and reset "pending" selectors */
state->num_selectors = 0;
state->sector = INNER_SPACE;
continue;
}
/*
if (sector == SELECTORS) { // inside selectors, condense all spaces
if (isspace(c)) { extra_space = 1; continue; }
else if (extra_space) {
*tobuf++ = ' ';
extra_space = 0;
}
}
*/
if (c == ':' && state->sector == PROPERTY) { /* end of property name */
state->sector = MIDDLE_SPACE;
continue;
}
if (c == ';' && state->sector == VALUE) { /* end of property value */
/* add prop/value to all pending rules */
for (j = 0; j < state->num_rules; j++)
css_rule_add_one(state->rules[j], state->property_buffer, strtrim(state->value_buffer));
//printf("Added `%s=%s` to %d rule(s)\n", buf3, buf4, num_rules);
state->sector = INNER_SPACE;
continue;
}
if (c == '}') {
if (state->sector == VALUE) {
/* add prop/value to all pending rules */
for (j = 0; j < state->num_rules; j++)
css_rule_add_one(state->rules[j], state->property_buffer, strtrim(state->value_buffer));
//printf("Added `%s=%s` to %d rule(s)\n", buf3, buf4, num_rules);
}
else if (state->sector != INNER_SPACE) {
fprintf(stderr, "Unexpected '}', expected value or ';'\n");
return 1;
}
/* reset rules */
state->num_rules = 0;
state->sector = OUTER_SPACE;
continue;
}
if (!isspace(c)) {
if (state->sector == INNER_SPACE) { /* start of property name */
state->sector = PROPERTY;
CHANGE_BUFFER(state->property_buffer); /* select "property" buffer for output */
}
if (state->sector == MIDDLE_SPACE) { /* start of value */
state->sector = VALUE;
CHANGE_BUFFER(state->value_buffer); /* select "value" buffer for output */
}
}
if (c == '"') { /* push/pop in-string */
if (state->sector == SUBSTRING) {
state->sector = state->prev_sector;
state->prev_sector = 0;
} else {
state->prev_sector = state->sector;
state->sector = SUBSTRING;
}
continue;
}
if (isalpha(c) || c == '*' || c == '.' || c == '#') {
if (state->sector == OUTER_SPACE) { /* start of selector(s) */
state->sector = SELECTORS;
CHANGE_BUFFER(state->selector_buffer); /* select "selectors" buffer for output */
}
}
/* Buffer overflow */
if (state->tobuf_space < 2) {
fprintf(stderr, "No buffer space to store selector/property/value, ABORTING parsing.\n");
return 1;
}
//printf("Saving `%c`, space left: %d\n", c, tobuf_space);
/* Save character to either buffer */
*state->tobuf++ = c;
*state->tobuf = 0;
state->tobuf_space--;
}
return 0;
}