diff options
Diffstat (limited to 'deps/npm/node_modules/tar/lib/parse.js')
-rw-r--r-- | deps/npm/node_modules/tar/lib/parse.js | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/deps/npm/node_modules/tar/lib/parse.js b/deps/npm/node_modules/tar/lib/parse.js new file mode 100644 index 0000000000..d9784b5ff7 --- /dev/null +++ b/deps/npm/node_modules/tar/lib/parse.js @@ -0,0 +1,253 @@ + +// A writable stream. +// It emits "entry" events, which provide a readable stream that has +// header info attached. + +module.exports = Parse.create = Parse + +var stream = require("stream") + , Stream = stream.Stream + , BlockStream = require("block-stream") + , tar = require("../tar.js") + , TarHeader = require("./header.js") + , Entry = require("./entry.js") + , BufferEntry = require("./buffer-entry.js") + , ExtendedHeader = require("./extended-header.js") + , assert = require("assert").ok + , inherits = require("inherits") + , fstream = require("fstream") + +// reading a tar is a lot like reading a directory +// However, we're actually not going to run the ctor, +// since it does a stat and various other stuff. +// This inheritance gives us the pause/resume/pipe +// behavior that is desired. +inherits(Parse, fstream.Reader) + +function Parse () { + var me = this + if (!(me instanceof Parse)) return new Parse() + + // doesn't apply fstream.Reader ctor? + // no, becasue we don't want to stat/etc, we just + // want to get the entry/add logic from .pipe() + Stream.apply(me) + + me.writable = true + me.readable = true + me._stream = new BlockStream(512) + + me._stream.on("error", function (e) { + me.emit("error", e) + }) + + me._stream.on("data", function (c) { + me._process(c) + }) + + me._stream.on("end", function () { + me._streamEnd() + }) + + me._stream.on("drain", function () { + me.emit("drain") + }) +} + +// overridden in Extract class, since it needs to +// wait for its DirWriter part to finish before +// emitting "end" +Parse.prototype._streamEnd = function () { + var me = this + if (!me._ended) me.error("unexpected eof") + me.emit("end") +} + +// a tar reader is actually a filter, not just a readable stream. +// So, you should pipe a tarball stream into it, and it needs these +// write/end methods to do that. +Parse.prototype.write = function (c) { + if (this._ended) { + return this.error("write() after end()") + } + return this._stream.write(c) +} + +Parse.prototype.end = function (c) { + this._ended = true + return this._stream.end(c) +} + +// don't need to do anything, since we're just +// proxying the data up from the _stream. +// Just need to override the parent's "Not Implemented" +// error-thrower. +Parse.prototype._read = function () {} + +Parse.prototype._process = function (c) { + assert(c && c.length === 512, "block size should be 512") + + // one of three cases. + // 1. A new header + // 2. A part of a file/extended header + // 3. One of two or more EOF null blocks + + if (this._entry) { + var entry = this._entry + entry.write(c) + if (entry._remaining === 0) { + entry.end() + this._entry = null + } + } else { + // either zeroes or a header + var zero = true + for (var i = 0; i < 512 && zero; i ++) { + zero = c[i] === 0 + } + + // eof is *at least* 2 blocks of nulls, and then the end of the + // file. you can put blocks of nulls between entries anywhere, + // so appending one tarball to another is technically valid. + // ending without the eof null blocks is not allowed, however. + if (zero) { + this._ended = this._eofStarted + this._eofStarted = true + } else { + this._ended = this._eofStarted = false + this._startEntry(c) + } + + } +} + +// take a header chunk, start the right kind of entry. +Parse.prototype._startEntry = function (c) { + var header = new TarHeader(c) + , self = this + , entry + , ev + , EntryType + , onend + , meta = false + + switch (tar.types[header.type]) { + case "File": + case "OldFile": + case "Link": + case "SymbolicLink": + case "CharacterDevice": + case "BlockDevice": + case "Directory": + case "FIFO": + case "ContiguousFile": + case "GNUDumpDir": + // start a file. + // pass in any extended headers + // These ones consumers are typically most interested in. + EntryType = Entry + ev = "entry" + break + + case "GlobalExtendedHeader": + // extended headers that apply to the rest of the tarball + EntryType = ExtendedHeader + onend = function () { + self._global = self._global || {} + Object.keys(entry.fields).forEach(function (k) { + self._global[k] = entry.fields[k] + }) + } + ev = "globalExtendedHeader" + meta = true + break + + case "ExtendedHeader": + case "OldExtendedHeader": + // extended headers that apply to the next entry + EntryType = ExtendedHeader + onend = function () { + self._extended = entry.fields + } + ev = "extendedHeader" + meta = true + break + + case "NextFileHasLongLinkpath": + // set linkpath=<contents> in extended header + EntryType = BufferEntry + onend = function () { + self._extended = self._extended || {} + self._extended.linkpath = entry.body + } + ev = "longLinkpath" + meta = true + break + + case "NextFileHasLongPath": + case "OldGnuLongPath": + // set path=<contents> in file-extended header + EntryType = BufferEntry + onend = function () { + self._extended = self._extended || {} + self._extended.path = entry.body + } + ev = "longPath" + meta = true + break + + default: + // all the rest we skip, but still set the _entry + // member, so that we can skip over their data appropriately. + // emit an event to say that this is an ignored entry type? + EntryType = Entry + ev = "ignoredEntry" + break + } + + var global, extended + if (meta) { + global = extended = null + } else { + var global = this._global + var extended = this._extended + + // extendedHeader only applies to one entry, so once we start + // an entry, it's over. + this._extended = null + } + entry = new EntryType(header, extended, global) + entry.meta = meta + + // only proxy data events of normal files. + if (!meta) { + entry.on("data", function (c) { + me.emit("data", c) + }) + } + + if (onend) entry.on("end", onend) + + this._entry = entry + var me = this + + entry.on("pause", function () { + me.pause() + }) + + entry.on("resume", function () { + me.resume() + }) + + if (this.listeners("*").length) { + this.emit("*", ev, entry) + } + + this.emit(ev, entry) + + // Zero-byte entry. End immediately. + if (entry.props.size === 0) { + entry.end() + this._entry = null + } +} |