diff options
Diffstat (limited to 'src/servo/css/lexer.rs')
| -rw-r--r-- | src/servo/css/lexer.rs | 266 |
1 files changed, 0 insertions, 266 deletions
diff --git a/src/servo/css/lexer.rs b/src/servo/css/lexer.rs deleted file mode 100644 index c0d5af6996a..00000000000 --- a/src/servo/css/lexer.rs +++ /dev/null @@ -1,266 +0,0 @@ -//! Code to lex and tokenize css files - -use option::is_none; -use str::from_bytes; -use vec::push; - -use pipes::{Port, Chan}; - -use lexer_util::*; - -use std::net::url::Url; -use std::cell::Cell; - -enum ParserState { - CssElement, - CssRelation, - CssDescription, - CssAttribute -} - -type CssLexer = { - input_state: InputState, - mut parser_state: ParserState -}; - -pub enum Token { - StartDescription, - EndDescription, - Descendant, - Child, - Sibling, - Comma, - Element(~str), - Attr(newcss::values::Attr), - Description(~str, ~str), - Eof -} - -trait CssLexerMethods { - fn parse_css() -> Token; - fn parse_css_relation(c : u8) -> Token; - fn parse_css_element(c : u8) -> Token; - fn parse_css_attribute(c : u8) -> Token; - fn parse_css_description(c: u8) -> Token; -} - -impl CssLexer : CssLexerMethods { - fn parse_css() -> Token { - let mut ch: u8; - match self.input_state.get() { - CoeChar(c) => ch = c, - CoeEof => { return Eof; } - } - - let token = match self.parser_state { - CssDescription => self.parse_css_description(ch), - CssAttribute => self.parse_css_attribute(ch), - CssElement => self.parse_css_element(ch), - CssRelation => self.parse_css_relation(ch) - }; - - #debug["token=%?", token]; - return move token; - } - - fn parse_css_relation(c : u8) -> Token { - self.parser_state = CssElement; - - let token = match c { - '{' as u8 => { self.parser_state = CssDescription; StartDescription } - '>' as u8 => { Child } - '+' as u8 => { Sibling } - ',' as u8 => { Comma } - _ => { self.input_state.unget(c); Descendant } - }; - - self.input_state.eat_whitespace(); - - return move token; - } - - fn parse_css_element(c : u8) -> Token { - assert is_none(&self.input_state.lookahead); - - /* Check for special attributes with an implied element, - or a wildcard which is not a alphabet character.*/ - if c == '.' as u8 || c == '#' as u8 { - self.parser_state = CssAttribute; - self.input_state.unget(c); - return Element(~"*"); - } else if c == '*' as u8 { - self.parser_state = CssAttribute; - return Element(~"*"); - } - - self.input_state.unget(c); - let element = self.input_state.parse_ident(); - - self.parser_state = CssAttribute; - - return move Element(move element); - } - - fn parse_css_attribute(c : u8) -> Token { - let mut ch = c; - - /* If we've reached the end of this list of attributes, - look for the relation to the next element.*/ - if c.is_whitespace() { - self.parser_state = CssRelation; - self.input_state.eat_whitespace(); - - match self.input_state.get() { - CoeChar(c) => { ch = c } - CoeEof => { fail ~"File ended before description of style" } - } - - return self.parse_css_relation(ch); - } - - match ch { - '.' as u8 => return Attr(newcss::values::Includes(~"class", self.input_state.parse_ident())), - '#' as u8 => return Attr(newcss::values::Includes(~"id", self.input_state.parse_ident())), - '[' as u8 => { - let attr_name = self.input_state.parse_ident(); - - match self.input_state.get() { - CoeChar(c) => { ch = c; } - CoeEof => { fail ~"File ended before description finished"; } - } - - if ch == ']' as u8 { - return Attr(newcss::values::Exists(move attr_name)); - } else if ch == '=' as u8 { - let attr_val = self.input_state.parse_ident(); - self.input_state.expect(']' as u8); - return Attr(newcss::values::Exact(move attr_name, move attr_val)); - } else if ch == '~' as u8 { - self.input_state.expect('=' as u8); - let attr_val = self.input_state.parse_ident(); - self.input_state.expect(']' as u8); - return Attr(newcss::values::Includes(move attr_name, move attr_val)); - } else if ch == '|' as u8 { - self.input_state.expect('=' as u8); - let attr_val = self.input_state.parse_ident(); - self.input_state.expect(']' as u8); - return Attr(newcss::values::StartsWith(move attr_name, move attr_val)); - } - - fail #fmt("Unexpected symbol %c in attribute", ch as char); - } - _ => { fail #fmt("Unexpected symbol %c in attribute", ch as char); } - } - } - - fn parse_css_description(c: u8) -> Token { - let mut ch = c; - - if ch == '}' as u8 { - self.parser_state = CssElement; - self.input_state.eat_whitespace(); - return EndDescription; - } else if ch.is_whitespace() { - self.input_state.eat_whitespace(); - - match self.input_state.get() { - CoeChar(c) => { ch = c } - CoeEof => { fail ~"Reached end of file in CSS description" } - } - } - - let mut desc_name = ~[]; - - // Get the name of the descriptor - loop { - if ch.is_whitespace() { - self.input_state.eat_whitespace(); - } else if ch == ':' as u8 { - if desc_name.len() == 0u { - fail ~"Expected descriptor name"; - } else { - break; - } - } else { - push(&mut desc_name, ch); - } - - match self.input_state.get() { - CoeChar(c) => { ch = c } - CoeEof => { fail ~"Reached end of file in CSS description" } - } - } - - self.input_state.eat_whitespace(); - let mut desc_val = ~[]; - - // Get the value of the descriptor - loop { - match self.input_state.get() { - CoeChar(c) => { ch = c } - CoeEof => { fail ~"Reached end of file in CSS description" } - } - - if ch.is_whitespace() { - self.input_state.eat_whitespace(); - } else if ch == '}' as u8 { - if desc_val.len() == 0u { - fail ~"Expected descriptor value"; - } else { - self.input_state.unget('}' as u8); - break; - } - } else if ch == ';' as u8 { - if desc_val.len() == 0u { - fail ~"Expected descriptor value"; - } else { - break; - } - } else { - push(&mut desc_val, ch); - } - } - - return Description(from_bytes(desc_name), from_bytes(desc_val)); - } -} - -fn parser(input: DataStream, state : ParserState) -> CssLexer { - return { - input_state: { - mut lookahead: None, - mut buffer: ~[], - input: input, - mut eof: false - }, - mut parser_state: state - }; -} - -pub fn lex_css_from_bytes(input_stream: DataStream, result_chan : &Chan<Token>) { - let lexer = parser(input_stream, CssElement); - - loop { - let token = lexer.parse_css(); - let should_break = match token { Eof => true, _ => false }; - - result_chan.send(move token); - - if should_break { - break; - } - } -} - -fn spawn_css_lexer_from_string(content : ~str) -> pipes::Port<Token> { - let (result_chan, result_port) = pipes::stream(); - - do task::spawn |move result_chan, move content| { - let content = str::to_bytes(content); - let content = Cell(copy content); - let input = |move content| if !content.is_empty() { Some(content.take()) } else { None }; - lex_css_from_bytes(input, &result_chan); - } - - return move result_port; -} |