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cloud-admin-template

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// https://github.com/Rob--W/open-in-browser export function getFilenameFromContentDispositionHeader(contentDisposition) { // This parser is designed to be tolerant and accepting of headers that do // not comply with the standard, but accepted by Firefox. let needsEncodingFixup = true; // filename*=ext-value ("ext-value" from RFC 5987, referenced by RFC 6266). let tmp = toParamRegExp('filename\\*', 'i').exec(contentDisposition); if (tmp) { tmp = tmp[1]; let filename = rfc2616unquote(tmp); filename = unescape(filename); filename = rfc5987decode(filename); filename = rfc2047decode(filename); return fixupEncoding(filename); } // Continuations (RFC 2231 section 3, referenced by RFC 5987 section 3.1). // filename*n*=part // filename*n=part tmp = rfc2231getparam(contentDisposition); if (tmp) { // RFC 2047, section const filename = rfc2047decode(tmp); return fixupEncoding(filename); } // filename=value (RFC 5987, section 4.1). tmp = toParamRegExp('filename', 'i').exec(contentDisposition); if (tmp) { tmp = tmp[1]; let filename = rfc2616unquote(tmp); filename = rfc2047decode(filename); return fixupEncoding(filename); } return ''; function toParamRegExp(attributePattern, flags) { return new RegExp( '(?:^|;)\\s*' + attributePattern + '\\s*=\\s*' // Captures: value = token | quoted-string // (RFC 2616, section 3.6 and referenced by RFC 6266 4.1) + '(' + '[^";\\s][^;\\s]*' + '|' + '"(?:[^"\\\\]|\\\\"?)+"?' + ')', flags, ); } function textdecode(encoding, value) { if (encoding) { try { const decoder = new TextDecoder(encoding, { fatal: true }); const bytes = Array.from(value, (c) => c.charCodeAt(0)); if (bytes.every((code) => code <= 0xFF)) { value = decoder.decode(new Uint8Array(bytes)); needsEncodingFixup = false; } } catch (e) { // TextDecoder constructor threw - unrecognized encoding. } } return value; } function fixupEncoding(value) { if (needsEncodingFixup && /[\x80-\xff]/.test(value)) { // Maybe multi-byte UTF-8. value = textdecode('utf-8', value); if (needsEncodingFixup) { // Try iso-8859-1 encoding. value = textdecode('iso-8859-1', value); } } return value; } function rfc2231getparam(contentDisposition) { const matches = []; let match; // Iterate over all filename*n= and filename*n*= with n being an integer // of at least zero. Any non-zero number must not start with '0'. const iter = toParamRegExp('filename\\*((?!0\\d)\\d+)(\\*?)', 'ig'); while ((match = iter.exec(contentDisposition)) !== null) { let [, n, quot, part] = match; n = parseInt(n); if (n in matches) { // Ignore anything after the invalid second filename*0. if (n === 0) break; continue; } matches[n] = [quot, part]; } const parts = []; for (let n = 0; n < matches.length; ++n) { if (!(n in matches)) { // Numbers must be consecutive. Truncate when there is a hole. break; } let [quot, part] = matches[n]; part = rfc2616unquote(part); if (quot) { part = unescape(part); if (n === 0) { part = rfc5987decode(part); } } parts.push(part); } return parts.join(''); } function rfc2616unquote(value) { if (value.startsWith('"')) { const parts = value.slice(1).split('\\"'); // Find the first unescaped " and terminate there. for (let i = 0; i < parts.length; ++i) { const quotindex = parts[i].indexOf('"'); if (quotindex !== -1) { parts[i] = parts[i].slice(0, quotindex); parts.length = i + 1; // Truncates and stop the iteration. } parts[i] = parts[i].replace(/\\(.)/g, '$1'); } value = parts.join('"'); } return value; } function rfc5987decode(extvalue) { // Decodes "ext-value" from RFC 5987. const encodingend = extvalue.indexOf('\''); if (encodingend === -1) { // Some servers send "filename*=" without encoding'language' prefix, // e.g. in https://github.com/Rob--W/open-in-browser/issues/26 // Let's accept the value like Firefox (57) (Chrome 62 rejects it). return extvalue; } const encoding = extvalue.slice(0, encodingend); const langvalue = extvalue.slice(encodingend + 1); // Ignore language (RFC 5987 section 3.2.1, and RFC 6266 section 4.1 ). const value = langvalue.replace(/^[^']*'/, ''); return textdecode(encoding, value); } function rfc2047decode(value) { // RFC 2047-decode the result. Firefox tried to drop support for it, but // backed out because some servers use it - https://bugzil.la/875615 // Firefox's condition for decoding is here: https://searchfox.org/mozilla-central/rev/4a590a5a15e35d88a3b23dd6ac3c471cf85b04a8/netwerk/mime/nsMIMEHeaderParamImpl.cpp#742-748 // We are more strict and only recognize RFC 2047-encoding if the value // starts with "=?", since then it is likely that the full value is // RFC 2047-encoded. // Firefox also decodes words even where RFC 2047 section 5 states: // "An 'encoded-word' MUST NOT appear within a 'quoted-string'." // eslint-disable-next-line no-control-regex if (!value.startsWith('=?') || /[\x00-\x19\x80-\xff]/.test(value)) { return value; } // RFC 2047, section 2.4 // encoded-word = "=?" charset "?" encoding "?" encoded-text "?=" // charset = token (but let's restrict to characters that denote a // possibly valid encoding). // encoding = q or b // encoded-text = any printable ASCII character other than ? or space. // ... but Firefox permits ? and space. return value.replace(/[=]\?([\w-]*)\?([QqBb])\?((?:[^?]|\?(?!=))*)\?=/g, (_, charset, encoding, text) => { if (encoding === 'q' || encoding === 'Q') { // RFC 2047 section 4.2. text = text.replace(/_/g, ' '); text = text.replace(/[=]([0-9a-fA-F]{2})/g, (_, hex) => String.fromCharCode(parseInt(hex, 16))); return textdecode(charset, text); } // else encoding is b or B - base64 (RFC 2047 section 4.1) try { text = atob(text); } catch (e) { } return textdecode(charset, text); }); } }