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1// parse a 512-byte header block to a data object, or vice-versa2// encode returns `true` if a pax extended header is needed, because3// the data could not be faithfully encoded in a simple header.4// (Also, check header.needPax to see if it needs a pax header.)5import { posix as pathModule } from 'node:path';6import * as large from './large-numbers.js';7import * as types from './types.js';8export class Header {9    cksumValid = false;10    needPax = false;11    nullBlock = false;12    block;13    path;14    mode;15    uid;16    gid;17    size;18    cksum;19    #type = 'Unsupported';20    linkpath;21    uname;22    gname;23    devmaj = 0;24    devmin = 0;25    atime;26    ctime;27    mtime;28    charset;29    comment;30    constructor(data, off = 0, ex, gex) {31        if (Buffer.isBuffer(data)) {32            this.decode(data, off || 0, ex, gex);33        }34        else if (data) {35            this.#slurp(data);36        }37    }38    decode(buf, off, ex, gex) {39        if (!off) {40            off = 0;41        }42        if (!buf || !(buf.length >= off + 512)) {43            throw new Error('need 512 bytes for header');44        }45        this.path = ex?.path ?? decString(buf, off, 100);46        this.mode = ex?.mode ?? gex?.mode ?? decNumber(buf, off + 100, 8);47        this.uid = ex?.uid ?? gex?.uid ?? decNumber(buf, off + 108, 8);48        this.gid = ex?.gid ?? gex?.gid ?? decNumber(buf, off + 116, 8);49        this.size = ex?.size ?? gex?.size ?? decNumber(buf, off + 124, 12);50        this.mtime =51            ex?.mtime ?? gex?.mtime ?? decDate(buf, off + 136, 12);52        this.cksum = decNumber(buf, off + 148, 12);53        // if we have extended or global extended headers, apply them now54        // See https://github.com/npm/node-tar/pull/18755        // Apply global before local, so it overrides56        if (gex)57            this.#slurp(gex, true);58        if (ex)59            this.#slurp(ex);60        // old tar versions marked dirs as a file with a trailing /61        const t = decString(buf, off + 156, 1);62        if (types.isCode(t)) {63            this.#type = t || '0';64        }65        if (this.#type === '0' && this.path.slice(-1) === '/') {66            this.#type = '5';67        }68        // tar implementations sometimes incorrectly put the stat(dir).size69        // as the size in the tarball, even though Directory entries are70        // not able to have any body at all.  In the very rare chance that71        // it actually DOES have a body, we weren't going to do anything with72        // it anyway, and it'll just be a warning about an invalid header.73        if (this.#type === '5') {74            this.size = 0;75        }76        this.linkpath = decString(buf, off + 157, 100);77        if (buf.subarray(off + 257, off + 265).toString() ===78            'ustar\u000000') {79            /* c8 ignore start */80            this.uname =81                ex?.uname ?? gex?.uname ?? decString(buf, off + 265, 32);82            this.gname =83                ex?.gname ?? gex?.gname ?? decString(buf, off + 297, 32);84            this.devmaj =85                ex?.devmaj ?? gex?.devmaj ?? decNumber(buf, off + 329, 8) ?? 0;86            this.devmin =87                ex?.devmin ?? gex?.devmin ?? decNumber(buf, off + 337, 8) ?? 0;88            /* c8 ignore stop */89            if (buf[off + 475] !== 0) {90                // definitely a prefix, definitely >130 chars.91                const prefix = decString(buf, off + 345, 155);92                this.path = prefix + '/' + this.path;93            }94            else {95                const prefix = decString(buf, off + 345, 130);96                if (prefix) {97                    this.path = prefix + '/' + this.path;98                }99                /* c8 ignore start */100                this.atime =101                    ex?.atime ?? gex?.atime ?? decDate(buf, off + 476, 12);102                this.ctime =103                    ex?.ctime ?? gex?.ctime ?? decDate(buf, off + 488, 12);104                /* c8 ignore stop */105            }106        }107        let sum = 8 * 0x20;108        for (let i = off; i < off + 148; i++) {109            sum += buf[i];110        }111        for (let i = off + 156; i < off + 512; i++) {112            sum += buf[i];113        }114        this.cksumValid = sum === this.cksum;115        if (this.cksum === undefined && sum === 8 * 0x20) {116            this.nullBlock = true;117        }118    }119    #slurp(ex, gex = false) {120        Object.assign(this, Object.fromEntries(Object.entries(ex).filter(([k, v]) => {121            // we slurp in everything except for the path attribute in122            // a global extended header, because that's weird. Also, any123            // null/undefined values are ignored.124            return !(v === null ||125                v === undefined ||126                (k === 'path' && gex) ||127                (k === 'linkpath' && gex) ||128                k === 'global');129        })));130    }131    encode(buf, off = 0) {132        if (!buf) {133            buf = this.block = Buffer.alloc(512);134        }135        if (this.#type === 'Unsupported') {136            this.#type = '0';137        }138        if (!(buf.length >= off + 512)) {139            throw new Error('need 512 bytes for header');140        }141        const prefixSize = this.ctime || this.atime ? 130 : 155;142        const split = splitPrefix(this.path || '', prefixSize);143        const path = split[0];144        const prefix = split[1];145        this.needPax = !!split[2];146        this.needPax = encString(buf, off, 100, path) || this.needPax;147        this.needPax =148            encNumber(buf, off + 100, 8, this.mode) || this.needPax;149        this.needPax =150            encNumber(buf, off + 108, 8, this.uid) || this.needPax;151        this.needPax =152            encNumber(buf, off + 116, 8, this.gid) || this.needPax;153        this.needPax =154            encNumber(buf, off + 124, 12, this.size) || this.needPax;155        this.needPax =156            encDate(buf, off + 136, 12, this.mtime) || this.needPax;157        buf[off + 156] = this.#type.charCodeAt(0);158        this.needPax =159            encString(buf, off + 157, 100, this.linkpath) || this.needPax;160        buf.write('ustar\u000000', off + 257, 8);161        this.needPax =162            encString(buf, off + 265, 32, this.uname) || this.needPax;163        this.needPax =164            encString(buf, off + 297, 32, this.gname) || this.needPax;165        this.needPax =166            encNumber(buf, off + 329, 8, this.devmaj) || this.needPax;167        this.needPax =168            encNumber(buf, off + 337, 8, this.devmin) || this.needPax;169        this.needPax =170            encString(buf, off + 345, prefixSize, prefix) || this.needPax;171        if (buf[off + 475] !== 0) {172            this.needPax =173                encString(buf, off + 345, 155, prefix) || this.needPax;174        }175        else {176            this.needPax =177                encString(buf, off + 345, 130, prefix) || this.needPax;178            this.needPax =179                encDate(buf, off + 476, 12, this.atime) || this.needPax;180            this.needPax =181                encDate(buf, off + 488, 12, this.ctime) || this.needPax;182        }183        let sum = 8 * 0x20;184        for (let i = off; i < off + 148; i++) {185            sum += buf[i];186        }187        for (let i = off + 156; i < off + 512; i++) {188            sum += buf[i];189        }190        this.cksum = sum;191        encNumber(buf, off + 148, 8, this.cksum);192        this.cksumValid = true;193        return this.needPax;194    }195    get type() {196        return (this.#type === 'Unsupported' ?197            this.#type198            : types.name.get(this.#type));199    }200    get typeKey() {201        return this.#type;202    }203    set type(type) {204        const c = String(types.code.get(type));205        if (types.isCode(c) || c === 'Unsupported') {206            this.#type = c;207        }208        else if (types.isCode(type)) {209            this.#type = type;210        }211        else {212            throw new TypeError('invalid entry type: ' + type);213        }214    }215}216const splitPrefix = (p, prefixSize) => {217    const pathSize = 100;218    let pp = p;219    let prefix = '';220    let ret = undefined;221    const root = pathModule.parse(p).root || '.';222    if (Buffer.byteLength(pp) < pathSize) {223        ret = [pp, prefix, false];224    }225    else {226        // first set prefix to the dir, and path to the base227        prefix = pathModule.dirname(pp);228        pp = pathModule.basename(pp);229        do {230            if (Buffer.byteLength(pp) <= pathSize &&231                Buffer.byteLength(prefix) <= prefixSize) {232                // both fit!233                ret = [pp, prefix, false];234            }235            else if (Buffer.byteLength(pp) > pathSize &&236                Buffer.byteLength(prefix) <= prefixSize) {237                // prefix fits in prefix, but path doesn't fit in path238                ret = [pp.slice(0, pathSize - 1), prefix, true];239            }240            else {241                // make path take a bit from prefix242                pp = pathModule.join(pathModule.basename(prefix), pp);243                prefix = pathModule.dirname(prefix);244            }245        } while (prefix !== root && ret === undefined);246        // at this point, found no resolution, just truncate247        if (!ret) {248            ret = [p.slice(0, pathSize - 1), '', true];249        }250    }251    return ret;252};253const decString = (buf, off, size) => buf254    .subarray(off, off + size)255    .toString('utf8')256    .replace(/\0.*/, '');257const decDate = (buf, off, size) => numToDate(decNumber(buf, off, size));258const numToDate = (num) => num === undefined ? undefined : new Date(num * 1000);259const decNumber = (buf, off, size) => Number(buf[off]) & 0x80 ?260    large.parse(buf.subarray(off, off + size))261    : decSmallNumber(buf, off, size);262const nanUndef = (value) => (isNaN(value) ? undefined : value);263const decSmallNumber = (buf, off, size) => nanUndef(parseInt(buf264    .subarray(off, off + size)265    .toString('utf8')266    .replace(/\0.*$/, '')267    .trim(), 8));268// the maximum encodable as a null-terminated octal, by field size269const MAXNUM = {270    12: 0o77777777777,271    8: 0o7777777,272};273const encNumber = (buf, off, size, num) => num === undefined ? false274    : num > MAXNUM[size] || num < 0 ?275        (large.encode(num, buf.subarray(off, off + size)), true)276        : (encSmallNumber(buf, off, size, num), false);277const encSmallNumber = (buf, off, size, num) => buf.write(octalString(num, size), off, size, 'ascii');278const octalString = (num, size) => padOctal(Math.floor(num).toString(8), size);279const padOctal = (str, size) => (str.length === size - 1 ?280    str281    : new Array(size - str.length - 1).join('0') + str + ' ') + '\0';282const encDate = (buf, off, size, date) => date === undefined ? false : (encNumber(buf, off, size, date.getTime() / 1000));283// enough to fill the longest string we've got284const NULLS = new Array(156).join('\0');285// pad with nulls, return true if it's longer or non-ascii286const encString = (buf, off, size, str) => str === undefined ? false : ((buf.write(str + NULLS, off, size, 'utf8'),287    str.length !== Buffer.byteLength(str) || str.length > size));288//# sourceMappingURL=header.js.map