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DOM select: Completely rewrite the parser for nth arguments

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This commit is contained in:
Jonas Fonseca 2005-12-20 01:50:39 +01:00 committed by Jonas Fonseca
parent c2e30c8eea
commit 5777941d06
1 changed files with 86 additions and 81 deletions
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167
src/document/dom/select.c
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@ -156,119 +156,124 @@ parse_dom_select_attribute(struct dom_select_node *sel, struct scanner *scanner)
* 1n+0 / n+0 / n
* 0n+0
*/
static enum dom_exception_code
parse_dom_select_nth_numeric(struct dom_select_nth_match *nth,
struct scanner_token *arg)
static size_t
get_scanner_token_number(struct scanner_token *token)
{
size_t sign = 1;
size_t number;
size_t number = 0;
/* Parse negated value: -0n+1 */
if (arg->string[0] == '-') {
arg->string++, arg->length--;
sign = -1;
if (arg->length == 0)
return DOM_ERR_SYNTAX;
}
/* Parse -n or n */
if (arg->string[0] == 'n') {
nth->step = sign;
arg->string++, arg->length--;
} else if (isdigit(arg->string[0])) {
number = 0;
do {
size_t old_number = number;
number *= 10;
if (old_number > number)
return DOM_ERR_NOT_SUPPORTED;
number += arg->string[0] - '0';
arg->string++, arg->length--;
} while (arg->length > 0 && isdigit(arg->string[0]));
if (arg->length > 0 && arg->string[0] == 'n') {
nth->step = number * sign;
arg->string++, arg->length--;
} else {
nth->step = 0;
nth->index = number * sign;
return DOM_ERR_NONE;
}
}
/* Parse the +... part of n+2 */
if (arg->length <= 1 || arg->string[0] != '+')
return DOM_ERR_NONE;
arg->string++, arg->length--;
/* Accept 2n+ */
if (!isdigit(arg->string[0]))
return DOM_ERR_NONE;
number = 0;
do {
while (token->length > 0 && isdigit(token->string[0])) {
size_t old_number = number;
number *= 10;
/* -E2BIG */
if (old_number > number)
return DOM_ERR_NOT_SUPPORTED;
return -1;
number += arg->string[0] - '0';
arg->string++, arg->length--;
number += token->string[0] - '0';
token->string++, token->length--;
}
} while (arg->length > 0 && isdigit(arg->string[0]));
nth->index = number * sign;
return DOM_ERR_NONE;
return number;
}
static enum dom_exception_code
parse_dom_select_nth_arg(struct dom_select_nth_match *nth, struct scanner *scanner)
{
struct scanner_token *token = get_next_scanner_token(scanner);
struct scanner_token arg;
int sign = 1;
int number = -1;
if (!token || token->type != '(')
return DOM_ERR_SYNTAX;
token = get_next_scanner_token(scanner);
if (!token || token->type == ')')
if (!token)
return DOM_ERR_SYNTAX;
copy_struct(&arg, token);
switch (token->type) {
case CSS_TOKEN_IDENT:
if (scanner_token_contains(token, "even")) {
nth->step = 2;
nth->index = 0;
do {
/* Combine all the arg material to one token. */
arg.length = (token->string + token->length) - arg.string;
} else if (scanner_token_contains(token, "odd")) {
nth->step = 2;
nth->index = 1;
} else {
/* Check for 'n' ident below. */
break;
}
if (skip_css_tokens(scanner, ')'))
return DOM_ERR_NONE;
return DOM_ERR_SYNTAX;
case '-':
sign = -1;
token = get_next_scanner_token(scanner);
if (!token) return DOM_ERR_SYNTAX;
} while (token->type != ')');
if (token->type != CSS_TOKEN_IDENT)
break;
if (scanner_token_contains(&arg, "even")) {
nth->step = 2;
nth->index = 0;
if (token->type != CSS_TOKEN_NUMBER)
return DOM_ERR_SYNTAX;
/* Fall-through */
} else if (scanner_token_contains(&arg, "odd")) {
nth->step = 2;
nth->index = 1;
case CSS_TOKEN_NUMBER:
number = get_scanner_token_number(token);
if (number < 0)
return DOM_ERR_INVALID_STATE;
} else if (arg.length > 0) {
return parse_dom_select_nth_numeric(nth, &arg);
token = get_next_scanner_token(scanner);
if (!token) return DOM_ERR_SYNTAX;
break;
return DOM_ERR_NONE;
default:
return DOM_ERR_SYNTAX;
}
return DOM_ERR_NONE;
/* The rest can contain n+ part */
switch (token->type) {
case CSS_TOKEN_IDENT:
if (!scanner_token_contains(token, "n"))
return DOM_ERR_SYNTAX;
nth->step = sign * number;
token = get_next_scanner_token(scanner);
if (!token) return DOM_ERR_SYNTAX;
if (token->type != '+')
break;
token = get_next_scanner_token(scanner);
if (!token) return DOM_ERR_SYNTAX;
if (token->type != CSS_TOKEN_NUMBER)
break;
number = get_scanner_token_number(token);
if (number < 0)
return DOM_ERR_INVALID_STATE;
nth->index = sign * number;
break;
default:
nth->step = 0;
nth->index = sign * number;
}
if (skip_css_tokens(scanner, ')'))
return DOM_ERR_NONE;
return DOM_ERR_SYNTAX;
}
static enum dom_exception_code