this is a PAC file parser using the new WebViewGadget as JavaScript engine. This are the features:
- compiles to a single file (needed js functions are included in the compiled binary)
- handles the provided PAC file content (you need to load/read the pac file by yourself)
- tested with PB 6.20 x64 on Windows 10 and Ubuntu 24.04, very likely also working on MacOS?
- the WebViewGadget has some drawback causing crashes in the worst case.
- I solved by giving time to process internal stuff before closing but you might need to increase the waiting time to become more reliable (if you experience crashes).
- See code comment, search for "crash".
- the alert() function is not working.
- I encapsulated and forwarded to console.log to prevent any error messages because, as the WebViewGadget is invisible, the alert is never visible to the user.
- In theory, it is possible to implement using a callback, but this likely depends on your environment.
- no guarantee that the contained JavaScript functions work in all environments and are error free. I have not tested all of them in detail. If you find errors or made enhancements, please share here below in this thread!
Code: Select all
; Parse PAC file using WebViewGadget
;
; PAC reference:
; https://developer.mozilla.org/en-US/docs/Web/HTTP/Proxy_servers_and_tunneling/Proxy_Auto-Configuration_PAC_file
;
; (c) 2025 / Volker Schmid
;
; PureBasic 6.20
EnableExplicit
DataSection
; Include the needed JS code into the generated binary so we do not
; create any file dependency for the runtime executable.
pac_include_js:
IncludeBinary #PB_Compiler_FilePath + "pac_include.js"
Data.a 0
EndDataSection
Structure pacInstance
winId.i ; the window id
webViewId.i ; the webviewgadget it
call.s ; the call to execute if DOM has loaded
result.s ; catches the result
EndStructure
Global globalPAC.pacInstance
Procedure _createPACEnvironment()
globalPAC\winId = OpenWindow(#PB_Any, 0, 0, 0, 0, "", #PB_Window_NoActivate)
If globalPAC\winId = 0
Debug "PAC: Failed to create dummy window"
End
EndIf
globalPAC\webViewId = WebViewGadget(#PB_Any, 0, 0, 0, 0) ; add #PB_WebView_Debug flag if needed
If globalPAC\webViewId = 0
Debug "PAC: Failed to create dummy WebViewGadget. Missing libraries/dependencies?"
End
EndIf
EndProcedure
Procedure _closePACEnvironment()
If IsGadget(globalPAC\webViewId)
FreeGadget(globalPAC\webViewId)
EndIf
If IsWindow(globalPAC\winId)
CloseWindow(globalPAC\winId)
EndIf
globalPAC\winId = 0
globalPAC\webViewId = 0
globalPAC\result = ""
globalPAC\call = ""
EndProcedure
; Triggered upon DOM loaded. Then triggers PAC file execution.
Procedure _pacTrigger(jsonParam.s)
WebViewExecuteScript(globalPAC\webViewId, globalPAC\call)
ProcedureReturn #Null
EndProcedure
; Receiving the result of PAC file execution
Procedure _pacCallback(jsonParam.s)
Protected json.i = ParseJSON(#PB_Any, jsonParam.s)
If JSONArraySize(JSONValue(json.i)) <> 1
Debug("PAC: _pacCallback had wrong parameter count!")
FreeJSON(json.i)
ProcedureReturn #Null
EndIf
Protected v.i = GetJSONElement(JSONValue(json.i), 0) ; 0 = url
Protected pacRes.s = GetJSONString(v.i)
FreeJSON(json.i)
globalPAC\result = pacRes.s
ProcedureReturn #Null
EndProcedure
Procedure.s ParsePACFile(PACfileContent.s, url.s, host.s)
_createPACEnvironment()
Protected includes.s = PeekS(?pac_include_js, -1, #PB_UTF8) ; the needed JS code
Protected html.s = ~"<!DOCTYPE html>\n<html><body><script>\n" + includes.s +
~"\n\n// ----------- user PAC function ------------\n" + PACfileContent.s +
~"\n\n// ----------- PB Helper ------------\n" +
~"function runPAC(url, host) {\n" +
~" var result = FindProxyForURL(url, host);\n" +
~" window.pacCallback(result); // run PB callback function\n" +
~"}\n" +
~"document.addEventListener(\"DOMContentLoaded\", () => {\n" +
~" window.pacTrigger();\n" +
~"});\n" +
~"</script></body></html>"
BindWebViewCallback(globalPAC\webViewId, "pacCallback", @_pacCallback())
BindWebViewCallback(globalPAC\webViewId, "pacTrigger", @_pacTrigger())
SetGadgetItemText(globalPAC\webViewId, #PB_Web_HtmlCode, html.s)
globalPac\call = ~"runPAC(\"" + url.s + ~"\", \"" + host.s + ~"\");"
; Wait for max 5 seconds for result
Protected startTime.i = ElapsedMilliseconds()
Protected event.i
Repeat
event = WindowEvent()
Delay(10)
Until globalPAC\result <> "" Or ElapsedMilliseconds() > startTime.i + 5000
Protected result.s = globalPAC\result ; keep because _closePACEnvironment() cleans up
startTime.i = ElapsedMilliseconds()
Repeat
event = WindowEvent()
Delay(1)
Until ElapsedMilliseconds() > startTime.i + 100 ; increase this time if you encounter a crash
UnbindWebViewCallback(globalPAC\webViewId, "pacCallback")
UnbindWebViewCallback(globalPAC\webViewId, "pacTrigger")
_closePACEnvironment()
ProcedureReturn result.s
EndProcedure
; RUNS ONLY IF YOU RUN THIS INCLUDE AS MAIN FILE
CompilerIf #PB_Compiler_IsMainFile = 1
; Helpful file loader for testing the PAC library
Procedure.s _testLoadFile(filename.s)
Protected fh.i = ReadFile(#PB_Any, filename.s, #PB_File_SharedRead)
If fh.i = 0
Debug "PAC: Failed to load [" + filename.s + "]"
ProcedureReturn ""
EndIf
Protected fl.i = Lof(fh.i)
Protected *mem = AllocateMemory(fl.i)
ReadData(fh.i, *mem, fl.i)
Protected content.s = PeekS(*mem, fl.i, #PB_UTF8 | #PB_ByteLength)
FreeMemory(*mem)
CloseFile(fh.i)
ProcedureReturn content.s
EndProcedure
Debug "PAC-Parser Result 1: [" + ParsePACFile(_testLoadFile("pac_testfile.pac"), "https://test.mozilla.org", "test.mozilla.org") + "]"
Debug "PAC-Parser Result 2: [" + ParsePACFile(_testLoadFile("pac_testfile.pac"), "https://www.google.com", "www.google.com") + "]"
CompilerEndIf
Code: Select all
var weekdayMap = {'SUN': 0, 'MON': 1, 'TUE': 2, 'WED': 3, 'THU': 4, 'FRI': 5, 'SAT': 6}; // Map weekday strings to numbers (SUN=0 to SAT=6)
var dnsCache = {}; // Cache DNS lookups
var ipCache = new Map(); // For isInNet caching
var timezoneOffset = new Date().getTimezoneOffset(); // Add time zone offset cache
function isPlainHostName(host) {
return host.indexOf('.') === -1;
}
function dnsDomainIs(host, domain) {
if (!domain.startsWith('.')) domain = '.' + domain;
return host.toLowerCase().endsWith(domain.toLowerCase());
}
function localHostOrDomainIs(host, hostDom) {
return host === hostDom || (!host.includes('.') && host === hostDom.split('.')[0]);
}
function dnsResolve(host) {
if (!dnsCache[host]) {
dnsCache[host] = helper_resolveDNS(host);
}
return dnsCache[host];
}
function helper_resolveDNS(host) {
let xhr = new XMLHttpRequest();
try {
xhr.open('GET', 'https://dns.google/resolve?name=' + encodeURIComponent(host), false);
xhr.send();
if (xhr.status != 200) {
console.error(`Error ${xhr.status}: ${xhr.statusText}`);
return "";
}
var response = xhr.response;
var json = JSON.parse(response);
console.log(json);
return json["Answer"][0]["data"];
} catch(err) { // instead of onerror
return "";
}
}
function isResolvable(host) {
try {
const ip = dnsResolve(host);
return ip !== null && ip.length > 0;
} catch (error) {
return false;
}
}
function myIpAddress() {
if (navigator.connection && navigator.connection.remoteAddresses) {
return Promise.resolve(
navigator.connection.remoteAddresses[0]
);
}
resolve(helper_getLocalIP());
}
function helper_getLocalIP() {
const RTCPeerConnection = window.RTCPeerConnection ||
window.mozRTCPeerConnection ||
window.webkitRTCPeerConnection;
if (!RTCPeerConnection) {
return '127.0.0.1';
}
const pc = new RTCPeerConnection();
const noop = () => {};
pc.createDataChannel('');
pc.createOffer(pc.setLocalDescription.bind(pc), noop);
return new Promise(resolve => {
pc.onicecandidate = event => {
if (event.candidate) {
resolve(event.candidate.candidate.split(':')[3]);
pc.close();
}
};
});
}
function helper_isValidIP(ip) {
const ipRegex = /^(\d{1,3}\.){3}\d{1,3}$/;
if (!ipRegex.test(ip)) return false;
const octets = ip.split('.');
return octets.every(octet => {
const num = parseInt(octet);
return num >= 0 && num <= 255;
});
}
function helper_ipToInteger(ip) {
const octets = ip.split('.');
let result = 0;
for (let i = 0; i < 4; i++) {
result = ((result << 8) | parseInt(octets[i]));
}
return result >>> 0;
}
function isInNet(host, pattern, mask) {
const key = `${host}:${pattern}:${mask}`;
if (ipCache.has(key)) {
return ipCache.get(key);
}
let ipToCheck = host;
if (!helper_isValidIP(host)) {
ipToCheck = dnsResolve(host);
if (!ipToCheck) return false;
}
const ipNum = helper_ipToInteger(ipToCheck);
const patternNum = helper_ipToInteger(pattern);
const maskNum = helper_ipToInteger(mask);
const result = (ipNum & maskNum) === (patternNum & maskNum);
ipCache.set(key, result);
return result;
}
function dnsDomainLevels(host) {
return host.split('.').length - 1;
}
function shExpMatch(str, pattern) {
const escapeRegex = str.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
const regexPattern = pattern.replace(/\*/g, '.*').replace(/\?/g, '.');
return new RegExp('^' + regexPattern + '$').test(escapeRegex);
}
function weekdayRange(wd1, wd2, gmt) {
const weekdays = ['SUN', 'MON', 'TUE', 'WED', 'THU', 'FRI', 'SAT'];
const now = new Date();
const currentDay = weekdays[now.getDay()];
if (!wd2) {
return currentDay === wd1.toUpperCase();
}
const startDay = weekdayMap[wd1.toUpperCase()];
const endDay = weekdayMap[wd2.toUpperCase()];
if (startDay > endDay) {
return currentDay >= wd1.toUpperCase() ||
currentDay <= wd2.toUpperCase();
}
return currentDay >= wd1.toUpperCase() &&
currentDay <= wd2.toUpperCase();
}
function timeRange(start, end, [gmt]) {
const now = new Date();
if (gmt) {
now.setTime(now.getTime() + (timezoneOffset * 60000));
}
const parseTime = (timeStr) => {
const [hours, minutes] = timeStr.split(':').map(Number);
return hours * 60 + minutes;
};
const currentTime = now.getHours() * 60 + now.getMinutes();
const startTime = parseTime(start);
const endTime = parseTime(end);
if (endTime < startTime) {
return currentTime >= startTime || currentTime <= endTime;
}
return currentTime >= startTime && currentTime <= endTime;
}
function dateRange(date1, date2, gmt = false) {
const now = new Date();
if (gmt) {
now.setTime(now.getTime() + (timezoneOffset * 60000));
}
const d1 = typeof date1 === 'string' ? new Date(date1) : date1;
const d2 = typeof date2 === 'string' ? new Date(date2) : date2;
return now >= d1 && now <= d2;
}
// Overwrite alert function because this does not
// work for our PB implementation
function alert(message) {
console.log(message);
}Code: Select all
function FindProxyForURL(url, host) {
if (
(isPlainHostName(host) || dnsDomainIs(host, ".mozilla.org")) &&
!localHostOrDomainIs(host, "www.mozilla.org") &&
!localHostOrDomainIs(host, "merchant.mozilla.org")
) {
return "DIRECT";
} else {
return "PROXY w3proxy.mozilla.org:8080; DIRECT";
}
}