ref: 3efb5bbb4061056e523858b134c555949591efe2
dir: /appl/lib/html.b/
implement HTML;
include "sys.m";
include "html.m";
include "strinttab.m";
sys: Sys;
T: StringIntTab;
Stringtab: adt
{
name: string;
val: int;
};
chartab:= array[] of { T->StringInt
("AElig", 'Æ'),
("Aacute", 'Á'),
("Acirc", 'Â'),
("Agrave", 'À'),
("Aring", 'Å'),
("Atilde", 'Ã'),
("Auml", 'Ä'),
("Ccedil", 'Ç'),
("ETH", 'Ð'),
("Eacute", 'É'),
("Ecirc", 'Ê'),
("Egrave", 'È'),
("Euml", 'Ë'),
("Iacute", 'Í'),
("Icirc", 'Î'),
("Igrave", 'Ì'),
("Iuml", 'Ï'),
("Ntilde", 'Ñ'),
("Oacute", 'Ó'),
("Ocirc", 'Ô'),
("Ograve", 'Ò'),
("Oslash", 'Ø'),
("Otilde", 'Õ'),
("Ouml", 'Ö'),
("THORN", 'Þ'),
("Uacute", 'Ú'),
("Ucirc", 'Û'),
("Ugrave", 'Ù'),
("Uuml", 'Ü'),
("Yacute", 'Ý'),
("aacute", 'á'),
("acirc", 'â'),
("acute", '´'),
("aelig", 'æ'),
("agrave", 'à'),
("alpha", 'α'),
("amp", '&'),
("aring", 'å'),
("atilde", 'ã'),
("auml", 'ä'),
("beta", 'β'),
("brvbar", '¦'),
("ccedil", 'ç'),
("cdots", '⋯'),
("cedil", '¸'),
("cent", '¢'),
("chi", 'χ'),
("copy", '©'),
("curren", '¤'),
("ddots", '⋱'),
("deg", '°'),
("delta", 'δ'),
("divide", '÷'),
("eacute", 'é'),
("ecirc", 'ê'),
("egrave", 'è'),
("emdash", '—'),
("emsp", ' '),
("endash", '–'),
("ensp", ' '),
("epsilon", 'ε'),
("eta", 'η'),
("eth", 'ð'),
("euml", 'ë'),
("frac12", '½'),
("frac14", '¼'),
("frac34", '¾'),
("gamma", 'γ'),
("gt", '>'),
("iacute", 'í'),
("icirc", 'î'),
("iexcl", '¡'),
("igrave", 'ì'),
("iota", 'ι'),
("iquest", '¿'),
("iuml", 'ï'),
("kappa", 'κ'),
("lambda", 'λ'),
("laquo", '«'),
("ldots", '…'),
("lt", '<'),
("macr", '¯'),
("micro", 'µ'),
("middot", '·'),
("mu", 'μ'),
("nbsp", ' '),
("not", '¬'),
("ntilde", 'ñ'),
("nu", 'ν'),
("oacute", 'ó'),
("ocirc", 'ô'),
("ograve", 'ò'),
("omega", 'ω'),
("omicron", 'ο'),
("ordf", 'ª'),
("ordm", 'º'),
("oslash", 'ø'),
("otilde", 'õ'),
("ouml", 'ö'),
("para", '¶'),
("phi", 'φ'),
("pi", 'π'),
("plusmn", '±'),
("pound", '£'),
("psi", 'ψ'),
("quad", ' '),
("quot", '"'),
("raquo", '»'),
("reg", '®'),
("rho", 'ρ'),
("sect", '§'),
("shy", ''),
("sigma", 'σ'),
("sp", ' '),
("sup1", '¹'),
("sup2", '²'),
("sup3", '³'),
("szlig", 'ß'),
("tau", 'τ'),
("theta", 'θ'),
("thinsp", ' '),
("thorn", 'þ'),
("times", '×'),
("trade", '™'),
("uacute", 'ú'),
("ucirc", 'û'),
("ugrave", 'ù'),
("uml", '¨'),
("upsilon", 'υ'),
("uuml", 'ü'),
("varepsilon", '∈'),
("varphi", 'ϕ'),
("varpi", 'ϖ'),
("varrho", 'ϱ'),
("vdots", '⋮'),
("vsigma", 'ς'),
("vtheta", 'ϑ'),
("xi", 'ξ'),
("yacute", 'ý'),
("yen", '¥'),
("yuml", 'ÿ'),
("zeta", 'ζ'),
};
htmlstringtab := array[] of { T->StringInt
("a", Ta),
("address", Taddress),
("applet", Tapplet),
("area", Tarea),
("att_footer", Tatt_footer),
("b", Tb),
("base", Tbase),
("basefont", Tbasefont),
("big", Tbig),
("blink", Tblink),
("blockquote", Tblockquote),
("body", Tbody),
("bq", Tbq),
("br", Tbr),
("caption", Tcaption),
("center", Tcenter),
("cite", Tcite),
("code", Tcode),
("col", Tcol),
("colgroup", Tcolgroup),
("dd", Tdd),
("dfn", Tdfn),
("dir", Tdir),
("div", Tdiv),
("dl", Tdl),
("dt", Tdt),
("em", Tem),
("font", Tfont),
("form", Tform),
("frame", Tframe),
("frameset", Tframeset),
("h1", Th1),
("h2", Th2),
("h3", Th3),
("h4", Th4),
("h5", Th5),
("h6", Th6),
("head", Thead),
("hr", Thr),
("html", Thtml),
("i", Ti),
("img", Timg),
("input", Tinput),
("isindex", Tisindex),
("item", Titem),
("kbd", Tkbd),
("li", Tli),
("link", Tlink),
("map", Tmap),
("menu", Tmenu),
("meta", Tmeta),
("nobr", Tnobr),
("noframes", Tnoframes),
("ol", Tol),
("option", Toption),
("p", Tp),
("param", Tparam),
("pre", Tpre),
("q", Tq),
("samp", Tsamp),
("script", Tscript),
("select", Tselect),
("small", Tsmall),
("strike", Tstrike),
("strong", Tstrong),
("style", Tstyle),
("sub", Tsub),
("sup", Tsup),
("t", Tt),
("table", Ttable),
("tbody", Ttbody),
("td", Ttd),
("textarea", Ttextarea),
("textflow", Ttextflow),
("tfoot", Ttfoot),
("th", Tth),
("thead", Tthead),
("title", Ttitle),
("tr", Ttr),
("tt", Ttt),
("u", Tu),
("ul", Tul),
("var", Tvar)
};
W, D, L, U, N: con byte (1<<iota);
NCTYPE: con 256;
ctype := array[NCTYPE] of {
'0'=>D, '1'=>D, '2'=>D, '3'=>D, '4'=>D,
'5'=>D, '6'=>D, '7'=>D, '8'=>D, '9'=>D,
'A'=>U, 'B'=>U, 'C'=>U, 'D'=>U, 'E'=>U, 'F'=>U,
'G'=>U, 'H'=>U, 'I'=>U, 'J'=>U, 'K'=>U, 'L'=>U,
'M'=>U, 'N'=>U, 'O'=>U, 'P'=>U, 'Q'=>U, 'R'=>U,
'S'=>U, 'T'=>U, 'U'=>U, 'V'=>U, 'W'=>U, 'X'=>U,
'Y'=>U, 'Z'=>U,
'a'=>L, 'b'=>L, 'c'=>L, 'd'=>L, 'e'=>L, 'f'=>L,
'g'=>L, 'h'=>L, 'i'=>L, 'j'=>L, 'k'=>L, 'l'=>L,
'm'=>L, 'n'=>L, 'o'=>L, 'p'=>L, 'q'=>L, 'r'=>L,
's'=>L, 't'=>L, 'u'=>L, 'v'=>L, 'w'=>L, 'x'=>L,
'y'=>L, 'z'=>L,
'.'=>N, '-'=>N,
' '=>W, '\n'=>W, '\t'=>W, '\r'=>W,
* => byte 0
};
lex(b: array of byte, charset: int, keepwh: int): array of ref Lex
{
if(sys == nil)
sys = load Sys Sys->PATH;
if(T == nil)
T = load StringIntTab StringIntTab->PATH;
if(T == nil) {
sys->print("HTML->lex: couldn't %s\n", StringIntTab->PATH);
return nil;
}
a: array of ref Lex;
ai := 0;
i := 0;
nb := len b;
for(;;){
Whitespace:
for(;;){
# ignore nulls
while(i<nb && (int b[i] == 0))
i++;
# skip white space
if(!keepwh) {
while(i<nb) {
c := int b[i];
if(!(int (ctype[c]&W)) && c != ' ')
break;
i++;
}
}
# skip comments
if(i<nb-4 && int b[i]=='<' && int b[i+1]=='!'
&& int b[i+2]=='-' && int b[i+3]=='-') {
i += 4;
while(i<nb-3){
if(int b[i]=='-' && int b[i+1]=='-' && int b[i+2]=='>'){
i += 3;
continue Whitespace;
}
i++;
}
continue Whitespace;
}
break;
}
if(i == nb)
break;
if(ai == len a){
na := array[len a + 500] of ref Lex;
if(a != nil)
na[0:] = a;
a = na;
}
if(int b[i] == '<'){
lx : ref Lex;
(lx, i) = gettag(b, i, charset);
a[ai++] = lx;
}
else {
s: string;
(s, i) = getdata(b, i, keepwh, charset);
a[ai++] = ref Lex (Data, s, nil);
}
}
return a[0:ai];
}
getdata(b: array of byte, i: int, keepnls, charset: int): (string, int)
{
s:= "";
j:= 0;
c: int;
nb := len b;
loop:
while(i < nb){
oldi := i;
case charset{
Latin1 =>
c = int b[i++];
UTF8 =>
j: int;
(c, j, nil) = sys->byte2char(b, i);
i += j;
}
case c {
0 or 16r1a =>
continue loop;
'<' =>
i = oldi;
break loop;
'&' =>
(c, i) = ampersand(b, i);
'\n' =>
if(!keepnls)
c = ' ';
'\r' =>
if(oldi > 0 && int b[oldi-1] == '\n')
continue loop;
if(keepnls)
c = '\n';
else
c = ' ';
}
s[j++] = c;
}
return (s, i);
}
gettag(b: array of byte, i, charset: int): (ref Lex, int)
{
rbra := 0;
nb := len b;
ans := ref Lex(Notfound, "", nil);
al: list of Attr;
if(++i == nb)
return (ans, i);
istart := i;
c := int b[i];
if(c == '/') {
rbra = RBRA;
if(++i == nb)
return (ans, i);
c = int b[i];
}
if(c>=NCTYPE || !int (ctype[c]&(L|U))) {
while(i < nb) {
c = int b[i++];
if(c == '>')
break;
}
ans.text = string b[istart:i];
return (ans, i);
}
namstart := i;
while(c<NCTYPE && int (ctype[c]&(L|U|D|N))) {
if(++i == nb) {
ans.text = string b[istart:i];
return (ans, i);
}
c = int b[i];
}
name := lowercase(b, namstart, i);
(fnd, tag) := T->lookup(htmlstringtab, name);
if(fnd)
ans.tag = tag+rbra;
else
ans.text = name;
attrloop:
while(i < nb){
# look for "ws name" or "ws name ws = ws val" (ws=whitespace)
# skip whitespace
while(c<NCTYPE && int (ctype[c]&W)) {
if(++i == nb)
break attrloop;
c = int b[i];
}
if(c == '>') {
i++;
break;
}
if(c == '<')
break; # error: unclosed tag
if(c>=NCTYPE || !int (ctype[c]&(L|U))) {
# error, not the start of a name
# skip to end of tag
while(i < nb) {
c = int b[i++];
if(c == '>')
break;
}
break attrloop;
}
# gather name
namstart = i;
while(c<NCTYPE && int (ctype[c]&(L|U|D|N))) {
if(++i == nb)
break attrloop;
c = int b[i];
}
name = lowercase(b, namstart, i);
# skip whitespace
while(c<NCTYPE && int (ctype[c]&W)) {
if(++i == nb)
break attrloop;
c = int b[i];
}
if(c != '=') {
# no value for this attr
al = (name, "") :: al;
continue attrloop;
}
# skip whitespace
if(++i == nb)
break attrloop;
c = int b[i];
while(c<NCTYPE && int (ctype[c]&W)) {
if(++i == nb)
break attrloop;
c = int b[i];
}
# gather value
quote := 0;
if(c == '\'' || c == '"') {
quote = c;
i++;
}
val := "";
nv := 0;
valloop:
while(i < nb) {
case charset{
Latin1 =>
c = int b[i++];
UTF8 =>
j: int;
(c, j, nil) = sys->byte2char(b, i);
i += j;
}
if(c == '>') {
if(quote) {
# c might be part of string (though not good style)
# but if line ends before close quote, assume
# there was an unmatched quote
for(k := i; k < nb; k++) {
c = int b[k];
if(c == quote) {
val[nv++] = '>';
continue valloop;
}
if(c == '\n') {
i--;
break valloop;
}
}
}
i--;
break valloop;
}
if(quote) {
if(c == quote)
break valloop;
if(c == '\n')
continue valloop;
if(c == '\t' || c == '\r')
c = ' ';
}
else {
if(c<NCTYPE && int (ctype[c]&W))
break valloop;
}
if(c == '&')
(c, i) = ampersand(b, i);
val[nv++] = c;
}
al = (name, val) :: al;
if(i < nb)
c = int b[i];
}
ans.attr = al;
return (ans, i);
}
ampersand(b: array of byte, i: int): (int, int)
{
starti := i;
c := 0;
nb := len b;
if(i >= nb)
return ('?', i);
fnd := 0;
ans := 0;
if(int b[i] == '#'){
i++;
while(i<nb){
d := int b[i];
if(!(int (ctype[d]&D)))
break;
c = c*10 + d-'0';
i++;
}
if(0<c && c<256) {
if(c==160)
c = ' '; # non-breaking space
ans = c;
fnd = 1;
}
}
else {
s := "";
k := 0;
c = int b[i];
if(int (ctype[c]&(L|U))) {
while(i<nb) {
c = int b[i];
if(!(int (ctype[c]&(L|U|D|N))))
break;
s[k++] = c;
i++;
}
}
(fnd, ans) = T->lookup(chartab, s);
}
if(!fnd)
return ('&', starti);
if(i<nb && (int b[i]==';' || int b[i]=='\n'))
i++;
return (ans, i);
}
lowercase(b: array of byte, istart, iend: int): string
{
l := "";
j := 0;
for(i:=istart; i<iend; i++) {
c := int b[i];
if(c < NCTYPE && int (ctype[c]&U))
l[j] = c-'A'+'a';
else
l[j] = c;
j++;
}
return l;
}
uppercase(s: string): string
{
l := "";
for(i:=0; i<len s; i++) {
c := s[i];
if(c < NCTYPE && int (ctype[c]&L))
l[i] = c+'A'-'a';
else
l[i] = c;
}
return l;
}
attrvalue(attr: list of Attr, name: string): (int, string)
{
while(attr != nil){
a := hd attr;
if(a.name == name)
return (1, a.value);
attr = tl attr;
}
return (0, "");
}
globalattr(html: array of ref Lex, tag: int, attr: string): (int, string)
{
for(i:=0; i<len html; i++)
if(html[i].tag == tag)
return attrvalue(html[i].attr, attr);
return (0, "");
}
isbreak(h: array of ref Lex, i: int): int
{
for(; i<len h; i++){
case h[i].tag{
Th1 or Th2 or Th3 or Th4 or Th5 or Th6 or
Tbr or Tp or Tbody or Taddress or Tblockquote or
Tul or Tdl or Tdir or Tmenu or Tol or Tpre or Thr or Tform =>
return 1;
Data =>
return 0;
}
}
return 0;
}
# for debugging
lex2string(l: ref Lex): string
{
ans := "";
tag := l.tag;
if(tag == HTML->Data)
ans = "'" + l.text + "'";
else {
ans = "<";
if(tag >= RBRA) {
tag -= RBRA;
ans = ans + "/";
}
tname := T->revlookup(htmlstringtab, tag);
if(tname != nil)
ans = ans + uppercase(tname);
for(al := l.attr; al != nil; al = tl al) {
a := hd al;
ans = ans + " " + a.name + "='" + a.value + "'";
}
ans = ans + ">";
}
return ans;
}