Home Page
Site Map
Login/out
Message Board
Download(c) 2005-2024 XLOG Technologies AG
/**
* Modern Albufeira Prolog Interpreter
*
* Warranty & Liability
* To the extent permitted by applicable law and unless explicitly
* otherwise agreed upon, XLOG Technologies AG makes no warranties
* regarding the provided information. XLOG Technologies AG assumes
* no liability that any problems might be solved with the information
* provided by XLOG Technologies AG.
*
* Rights & License
* All industrial property rights regarding the information - copyright
* and patent rights in particular - are the sole property of XLOG
* Technologies AG. If the company was not the originator of some
* excerpts, XLOG Technologies AG has at least obtained the right to
* reproduce, change and translate the information.
*
* Reproduction is restricted to the whole unaltered document. Reproduction
* of the information is only allowed for non-commercial uses. Selling,
* giving away or letting of the execution of the library is prohibited.
* The library can be distributed as part of your applications and libraries
* for execution provided this comment remains unchanged.
*
* Restrictions
* Only to be distributed with programs that add significant and primary
* functionality to the library. Not to be distributed with additional
* software intended to replace any components of the library.
*
* Trademarks
* Jekejeke is a registered trademark of XLOG Technologies AG.
*/
import {deref, exec_unify, exec_build, check_atom,
is_variable, unify,
check_sink, Source, Sink, add, make_check, char_count
} from "../../dogelog.mjs";
/*********************************************************************/
/* open_input_atom_stream/2, open_output_atom_stream/1 and close_output_atom_stream/2 */
/*********************************************************************/
/**
* open_input_atom_stream(A, S): internal only
* The built-in succeeds in S with a new input stream for the atom A.
*/
function test_open_input_atom_stream(args) {
let text = deref(exec_build(args[0]));
check_atom(text);
let src = new Source();
src.buf = text;
return exec_unify(args[1], src);
}
/**
* open_output_atom_stream(S): internal only
* The built-in succeeds in S with a new output stream.
*/
function test_open_output_atom_stream(args) {
let dst = new Sink();
dst.data = [];
dst.send = mem_send;
return exec_unify(args[0], dst);
}
function mem_send(data, buf) {
data.push(buf);
}
/**
* close_output_atom_stream(S, A): internal only
* The built-in succeeds in A with the content of the output stream S.
*/
function test_close_output_atom_stream(args) {
let writer = deref(exec_build(args[0]));
check_sink(writer);
writer = writer.data.join("");
return exec_unify(args[1], writer);
}
/*********************************************************************/
/* XML Escape */
/*********************************************************************/
/**
* xml_escape(X, Y):
* The predicate succeeds in Y with the XML escape of X.
*/
function test_xml_escape(args) {
let alpha = deref(exec_build(args[0]));
check_atom(alpha);
alpha = xml_escape(alpha);
return exec_unify(args[1], alpha);
}
export function xml_escape(text) {
let res = "";
let back = 0;
let i = 0;
while (i < text.length) {
let ch = text.codePointAt(i);
let elem;
switch (ch) {
case 34: // "
elem = """;
break;
case 38: // &
elem = "&";
break;
case 39: // '
elem = "'";
break;
case 60: // <
elem = "<";
break;
case 62: // >
elem = ">";
break;
default:
elem = null;
break;
}
if (elem !== null) {
res += text.slice(back, i);
res += elem;
back = i + 1;
}
i += char_count(ch);
}
if (back !== 0) {
res += text.slice(back);
text = res;
}
return text;
}
/*********************************************************************/
/* Percent Encode */
/*********************************************************************/
/**
* percent_encode(X, Y):
* The predicate succeeds in Y with the percent encode of X.
*/
function test_percent_encode(args) {
let alpha = deref(exec_build(args[0]));
if (is_variable(alpha)) {
let beta = deref(exec_build(args[1]));
beta = percent_decode(beta);
return unify(alpha, beta);
} else {
check_atom(alpha);
alpha = percent_encode(alpha);
return exec_unify(args[1], alpha);
}
}
function percent_encode(text) {
let res = "";
let back = 0;
let i = 0;
while (i < text.length) {
let ch = text.codePointAt(i);
i += char_count(ch);
let elem;
switch (ch) {
case 32: // space
elem = "+";
break;
case 35: // #
elem = "%23";
break;
case 37: // %
elem = "%25";
break;
case 38: // &
elem = "%26";
break;
case 43: // +
elem = "%2B";
break;
case 61: // =
elem = "%3D";
break;
case 63: // ?
elem = "%3F";
break;
case 92: // \
elem = "%5C";
break;
default:
elem = null;
break;
}
if (elem !== null) {
res += text.slice(back, i - 1);
res += elem;
back = i;
}
}
if (back !== 0) {
res += text.slice(back);
text = res;
}
return text;
}
function percent_decode(text) {
let res = "";
let back = 0;
let i = 0;
while (i < text.length) {
let ch = text.codePointAt(i);
i += char_count(ch);
if (ch === 37) { // %
let octet = octet_hex(text, i);
if (0 <= octet && octet < 128) {
res += text.slice(back, i - 1);
res += String.fromCodePoint(octet);
i += 2;
back = i;
} else if (192 <= octet && octet < 224) {
let octet2 = percent_hex(text, i + 2);
if (128 <= octet2 && octet2 < 192) {
res += text.slice(back, i - 1);
res += String.fromCodePoint((octet - 192) * 64 + (octet2 - 128));
i += 5;
back = i;
}
} else if (224 <= octet && octet < 240) {
let octet2 = percent_hex(text, i + 2);
if (128 <= octet2 && octet2 < 192) {
octet = (octet - 224) * 64 + (octet2 - 128);
octet2 = percent_hex(text, i + 5);
if (128 <= octet2 && octet2 < 192) {
res += text.slice(back, i - 1);
res += String.fromCodePoint(octet * 64 + (octet2 - 128));
i += 8;
back = i;
}
}
} else if (240 <= octet && octet < 248) {
let octet2 = percent_hex(text, i + 2);
if (128 <= octet2 && octet2 < 192) {
octet = (octet - 240) * 64 + (octet2 - 128);
octet2 = percent_hex(text, i + 5);
if (128 <= octet2 && octet2 < 192) {
octet = octet * 64 + (octet2 - 128);
octet2 = percent_hex(text, i + 8);
if (128 <= octet2 && octet2 < 192) {
res += text.slice(back, i - 1);
res += String.fromCodePoint(octet * 64 + (octet2 - 128));
i += 11;
back = i;
}
}
}
}
} else if (ch === 43) { // +
res += text.slice(back, i - 1);
res += String.fromCodePoint(32); // space
back = i;
}
}
if (back !== 0) {
res += text.slice(back);
text = res;
}
return text;
}
function percent_hex(text, i) {
let ch = (i < text.length ? text.charCodeAt(i) : -1);
if (ch === 37) {
i++;
return octet_hex(text, i);
}
return -1;
}
function octet_hex(text, i) {
let val = digit_hex(i < text.length ? text.charCodeAt(i) : -1);
if (val !== -1) {
i++;
let val2 = digit_hex(i < text.length ? text.charCodeAt(i) : -1);
if (val2 !== -1) {
return val * 16 + val2;
}
}
return -1;
}
function digit_hex(ch) {
if (48 <= ch && ch <= 57) return ch - 48;
if (65 <= ch && ch <= 70) return ch - 65 + 10;
if (97 <= ch && ch <= 102) return ch - 97 + 10;
return -1;
}
/*********************************************************************/
/* Aux Lib Init */
/*********************************************************************/
export function main() {
// system specials, input/output, internal only
add("open_input_atom_stream", 2, make_check(test_open_input_atom_stream));
add("open_output_atom_stream", 1, make_check(test_open_output_atom_stream));
add("close_output_atom_stream", 2, make_check(test_close_output_atom_stream));
add("xml_escape", 2, make_check(test_xml_escape));
add("percent_encode", 2, make_check(test_percent_encode));
}