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-rw-r--r--node_modules/bl/BufferList.js396
1 files changed, 396 insertions, 0 deletions
diff --git a/node_modules/bl/BufferList.js b/node_modules/bl/BufferList.js
new file mode 100644
index 0000000..471ee77
--- /dev/null
+++ b/node_modules/bl/BufferList.js
@@ -0,0 +1,396 @@
+'use strict'
+
+const { Buffer } = require('buffer')
+const symbol = Symbol.for('BufferList')
+
+function BufferList (buf) {
+ if (!(this instanceof BufferList)) {
+ return new BufferList(buf)
+ }
+
+ BufferList._init.call(this, buf)
+}
+
+BufferList._init = function _init (buf) {
+ Object.defineProperty(this, symbol, { value: true })
+
+ this._bufs = []
+ this.length = 0
+
+ if (buf) {
+ this.append(buf)
+ }
+}
+
+BufferList.prototype._new = function _new (buf) {
+ return new BufferList(buf)
+}
+
+BufferList.prototype._offset = function _offset (offset) {
+ if (offset === 0) {
+ return [0, 0]
+ }
+
+ let tot = 0
+
+ for (let i = 0; i < this._bufs.length; i++) {
+ const _t = tot + this._bufs[i].length
+ if (offset < _t || i === this._bufs.length - 1) {
+ return [i, offset - tot]
+ }
+ tot = _t
+ }
+}
+
+BufferList.prototype._reverseOffset = function (blOffset) {
+ const bufferId = blOffset[0]
+ let offset = blOffset[1]
+
+ for (let i = 0; i < bufferId; i++) {
+ offset += this._bufs[i].length
+ }
+
+ return offset
+}
+
+BufferList.prototype.get = function get (index) {
+ if (index > this.length || index < 0) {
+ return undefined
+ }
+
+ const offset = this._offset(index)
+
+ return this._bufs[offset[0]][offset[1]]
+}
+
+BufferList.prototype.slice = function slice (start, end) {
+ if (typeof start === 'number' && start < 0) {
+ start += this.length
+ }
+
+ if (typeof end === 'number' && end < 0) {
+ end += this.length
+ }
+
+ return this.copy(null, 0, start, end)
+}
+
+BufferList.prototype.copy = function copy (dst, dstStart, srcStart, srcEnd) {
+ if (typeof srcStart !== 'number' || srcStart < 0) {
+ srcStart = 0
+ }
+
+ if (typeof srcEnd !== 'number' || srcEnd > this.length) {
+ srcEnd = this.length
+ }
+
+ if (srcStart >= this.length) {
+ return dst || Buffer.alloc(0)
+ }
+
+ if (srcEnd <= 0) {
+ return dst || Buffer.alloc(0)
+ }
+
+ const copy = !!dst
+ const off = this._offset(srcStart)
+ const len = srcEnd - srcStart
+ let bytes = len
+ let bufoff = (copy && dstStart) || 0
+ let start = off[1]
+
+ // copy/slice everything
+ if (srcStart === 0 && srcEnd === this.length) {
+ if (!copy) {
+ // slice, but full concat if multiple buffers
+ return this._bufs.length === 1
+ ? this._bufs[0]
+ : Buffer.concat(this._bufs, this.length)
+ }
+
+ // copy, need to copy individual buffers
+ for (let i = 0; i < this._bufs.length; i++) {
+ this._bufs[i].copy(dst, bufoff)
+ bufoff += this._bufs[i].length
+ }
+
+ return dst
+ }
+
+ // easy, cheap case where it's a subset of one of the buffers
+ if (bytes <= this._bufs[off[0]].length - start) {
+ return copy
+ ? this._bufs[off[0]].copy(dst, dstStart, start, start + bytes)
+ : this._bufs[off[0]].slice(start, start + bytes)
+ }
+
+ if (!copy) {
+ // a slice, we need something to copy in to
+ dst = Buffer.allocUnsafe(len)
+ }
+
+ for (let i = off[0]; i < this._bufs.length; i++) {
+ const l = this._bufs[i].length - start
+
+ if (bytes > l) {
+ this._bufs[i].copy(dst, bufoff, start)
+ bufoff += l
+ } else {
+ this._bufs[i].copy(dst, bufoff, start, start + bytes)
+ bufoff += l
+ break
+ }
+
+ bytes -= l
+
+ if (start) {
+ start = 0
+ }
+ }
+
+ // safeguard so that we don't return uninitialized memory
+ if (dst.length > bufoff) return dst.slice(0, bufoff)
+
+ return dst
+}
+
+BufferList.prototype.shallowSlice = function shallowSlice (start, end) {
+ start = start || 0
+ end = typeof end !== 'number' ? this.length : end
+
+ if (start < 0) {
+ start += this.length
+ }
+
+ if (end < 0) {
+ end += this.length
+ }
+
+ if (start === end) {
+ return this._new()
+ }
+
+ const startOffset = this._offset(start)
+ const endOffset = this._offset(end)
+ const buffers = this._bufs.slice(startOffset[0], endOffset[0] + 1)
+
+ if (endOffset[1] === 0) {
+ buffers.pop()
+ } else {
+ buffers[buffers.length - 1] = buffers[buffers.length - 1].slice(0, endOffset[1])
+ }
+
+ if (startOffset[1] !== 0) {
+ buffers[0] = buffers[0].slice(startOffset[1])
+ }
+
+ return this._new(buffers)
+}
+
+BufferList.prototype.toString = function toString (encoding, start, end) {
+ return this.slice(start, end).toString(encoding)
+}
+
+BufferList.prototype.consume = function consume (bytes) {
+ // first, normalize the argument, in accordance with how Buffer does it
+ bytes = Math.trunc(bytes)
+ // do nothing if not a positive number
+ if (Number.isNaN(bytes) || bytes <= 0) return this
+
+ while (this._bufs.length) {
+ if (bytes >= this._bufs[0].length) {
+ bytes -= this._bufs[0].length
+ this.length -= this._bufs[0].length
+ this._bufs.shift()
+ } else {
+ this._bufs[0] = this._bufs[0].slice(bytes)
+ this.length -= bytes
+ break
+ }
+ }
+
+ return this
+}
+
+BufferList.prototype.duplicate = function duplicate () {
+ const copy = this._new()
+
+ for (let i = 0; i < this._bufs.length; i++) {
+ copy.append(this._bufs[i])
+ }
+
+ return copy
+}
+
+BufferList.prototype.append = function append (buf) {
+ if (buf == null) {
+ return this
+ }
+
+ if (buf.buffer) {
+ // append a view of the underlying ArrayBuffer
+ this._appendBuffer(Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength))
+ } else if (Array.isArray(buf)) {
+ for (let i = 0; i < buf.length; i++) {
+ this.append(buf[i])
+ }
+ } else if (this._isBufferList(buf)) {
+ // unwrap argument into individual BufferLists
+ for (let i = 0; i < buf._bufs.length; i++) {
+ this.append(buf._bufs[i])
+ }
+ } else {
+ // coerce number arguments to strings, since Buffer(number) does
+ // uninitialized memory allocation
+ if (typeof buf === 'number') {
+ buf = buf.toString()
+ }
+
+ this._appendBuffer(Buffer.from(buf))
+ }
+
+ return this
+}
+
+BufferList.prototype._appendBuffer = function appendBuffer (buf) {
+ this._bufs.push(buf)
+ this.length += buf.length
+}
+
+BufferList.prototype.indexOf = function (search, offset, encoding) {
+ if (encoding === undefined && typeof offset === 'string') {
+ encoding = offset
+ offset = undefined
+ }
+
+ if (typeof search === 'function' || Array.isArray(search)) {
+ throw new TypeError('The "value" argument must be one of type string, Buffer, BufferList, or Uint8Array.')
+ } else if (typeof search === 'number') {
+ search = Buffer.from([search])
+ } else if (typeof search === 'string') {
+ search = Buffer.from(search, encoding)
+ } else if (this._isBufferList(search)) {
+ search = search.slice()
+ } else if (Array.isArray(search.buffer)) {
+ search = Buffer.from(search.buffer, search.byteOffset, search.byteLength)
+ } else if (!Buffer.isBuffer(search)) {
+ search = Buffer.from(search)
+ }
+
+ offset = Number(offset || 0)
+
+ if (isNaN(offset)) {
+ offset = 0
+ }
+
+ if (offset < 0) {
+ offset = this.length + offset
+ }
+
+ if (offset < 0) {
+ offset = 0
+ }
+
+ if (search.length === 0) {
+ return offset > this.length ? this.length : offset
+ }
+
+ const blOffset = this._offset(offset)
+ let blIndex = blOffset[0] // index of which internal buffer we're working on
+ let buffOffset = blOffset[1] // offset of the internal buffer we're working on
+
+ // scan over each buffer
+ for (; blIndex < this._bufs.length; blIndex++) {
+ const buff = this._bufs[blIndex]
+
+ while (buffOffset < buff.length) {
+ const availableWindow = buff.length - buffOffset
+
+ if (availableWindow >= search.length) {
+ const nativeSearchResult = buff.indexOf(search, buffOffset)
+
+ if (nativeSearchResult !== -1) {
+ return this._reverseOffset([blIndex, nativeSearchResult])
+ }
+
+ buffOffset = buff.length - search.length + 1 // end of native search window
+ } else {
+ const revOffset = this._reverseOffset([blIndex, buffOffset])
+
+ if (this._match(revOffset, search)) {
+ return revOffset
+ }
+
+ buffOffset++
+ }
+ }
+
+ buffOffset = 0
+ }
+
+ return -1
+}
+
+BufferList.prototype._match = function (offset, search) {
+ if (this.length - offset < search.length) {
+ return false
+ }
+
+ for (let searchOffset = 0; searchOffset < search.length; searchOffset++) {
+ if (this.get(offset + searchOffset) !== search[searchOffset]) {
+ return false
+ }
+ }
+ return true
+}
+
+;(function () {
+ const methods = {
+ readDoubleBE: 8,
+ readDoubleLE: 8,
+ readFloatBE: 4,
+ readFloatLE: 4,
+ readInt32BE: 4,
+ readInt32LE: 4,
+ readUInt32BE: 4,
+ readUInt32LE: 4,
+ readInt16BE: 2,
+ readInt16LE: 2,
+ readUInt16BE: 2,
+ readUInt16LE: 2,
+ readInt8: 1,
+ readUInt8: 1,
+ readIntBE: null,
+ readIntLE: null,
+ readUIntBE: null,
+ readUIntLE: null
+ }
+
+ for (const m in methods) {
+ (function (m) {
+ if (methods[m] === null) {
+ BufferList.prototype[m] = function (offset, byteLength) {
+ return this.slice(offset, offset + byteLength)[m](0, byteLength)
+ }
+ } else {
+ BufferList.prototype[m] = function (offset = 0) {
+ return this.slice(offset, offset + methods[m])[m](0)
+ }
+ }
+ }(m))
+ }
+}())
+
+// Used internally by the class and also as an indicator of this object being
+// a `BufferList`. It's not possible to use `instanceof BufferList` in a browser
+// environment because there could be multiple different copies of the
+// BufferList class and some `BufferList`s might be `BufferList`s.
+BufferList.prototype._isBufferList = function _isBufferList (b) {
+ return b instanceof BufferList || BufferList.isBufferList(b)
+}
+
+BufferList.isBufferList = function isBufferList (b) {
+ return b != null && b[symbol]
+}
+
+module.exports = BufferList
generated by cgit (git 2.34.1) at 2024-10-22 07:34:45 +0000