commit

node_modules/streamsearch/.eslintrc.js

@@ -0,0 +1,5 @@
+'use strict';
+
+module.exports = {
+  extends: '@mscdex/eslint-config',
+};

node_modules/streamsearch/.github/workflows/ci.yml

@@ -0,0 +1,24 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+
+jobs:
+  tests-linux:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        node-version: [10.x, 12.x, 14.x, 16.x]
+    steps:
+      - uses: actions/checkout@v2
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+      - name: Install module
+        run: npm install
+      - name: Run tests
+        run: npm test

node_modules/streamsearch/.github/workflows/lint.yml

@@ -0,0 +1,23 @@
+name: lint
+
+on:
+  pull_request:
+  push:
+    branches: [ master ]
+
+env:
+  NODE_VERSION: 16.x
+
+jobs:
+  lint-js:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Use Node.js ${{ env.NODE_VERSION }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+      - name: Install ESLint + ESLint configs/plugins
+        run: npm install --only=dev
+      - name: Lint files
+        run: npm run lint

node_modules/streamsearch/LICENSE

@@ -0,0 +1,19 @@
+Copyright Brian White. All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to
+deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+IN THE SOFTWARE.

node_modules/streamsearch/README.md

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+Description
+===========
+
+streamsearch is a module for [node.js](http://nodejs.org/) that allows searching a stream using the Boyer-Moore-Horspool algorithm.
+
+This module is based heavily on the Streaming Boyer-Moore-Horspool C++ implementation by Hongli Lai [here](https://github.com/FooBarWidget/boyer-moore-horspool).
+
+
+Requirements
+============
+
+* [node.js](http://nodejs.org/) -- v10.0.0 or newer
+
+
+Installation
+============
+
+    npm install streamsearch
+
+Example
+=======
+
+```js
+  const { inspect } = require('util');
+
+  const StreamSearch = require('streamsearch');
+
+  const needle = Buffer.from('\r\n');
+  const ss = new StreamSearch(needle, (isMatch, data, start, end) => {
+    if (data)
+      console.log('data: ' + inspect(data.toString('latin1', start, end)));
+    if (isMatch)
+      console.log('match!');
+  });
+
+  const chunks = [
+    'foo',
+    ' bar',
+    '\r',
+    '\n',
+    'baz, hello\r',
+    '\n world.',
+    '\r\n Node.JS rules!!\r\n\r\n',
+  ];
+  for (const chunk of chunks)
+    ss.push(Buffer.from(chunk));
+
+  // output:
+  //
+  // data: 'foo'
+  // data: ' bar'
+  // match!
+  // data: 'baz, hello'
+  // match!
+  // data: ' world.'
+  // match!
+  // data: ' Node.JS rules!!'
+  // match!
+  // data: ''
+  // match!
+```
+
+
+API
+===
+
+Properties
+----------
+
+* **maxMatches** - < _integer_ > - The maximum number of matches. Defaults to `Infinity`.
+
+* **matches** - < _integer_ > - The current match count.
+
+
+Functions
+---------
+
+* **(constructor)**(< _mixed_ >needle, < _function_ >callback) - Creates and returns a new instance for searching for a _Buffer_ or _string_ `needle`. `callback` is called any time there is non-matching data and/or there is a needle match. `callback` will be called with the following arguments:
+
+  1. `isMatch` - _boolean_ - Indicates whether a match has been found
+
+  2. `data` - _mixed_ - If set, this contains data that did not match the needle.
+
+  3. `start` - _integer_ - The index in `data` where the non-matching data begins (inclusive).
+
+  4. `end` - _integer_ - The index in `data` where the non-matching data ends (exclusive).
+
+  5. `isSafeData` - _boolean_ - Indicates if it is safe to store a reference to `data` (e.g. as-is or via `data.slice()`) or not, as in some cases `data` may point to a Buffer whose contents change over time.
+
+* **destroy**() - _(void)_ - Emits any last remaining unmatched data that may still be buffered and then resets internal state.
+
+* **push**(< _Buffer_ >chunk) - _integer_ - Processes `chunk`, searching for a match. The return value is the last processed index in `chunk` + 1.
+
+* **reset**() - _(void)_ - Resets internal state. Useful for when you wish to start searching a new/different stream for example.
+

node_modules/streamsearch/lib/sbmh.js

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+'use strict';
+/*
+  Based heavily on the Streaming Boyer-Moore-Horspool C++ implementation
+  by Hongli Lai at: https://github.com/FooBarWidget/boyer-moore-horspool
+*/
+function memcmp(buf1, pos1, buf2, pos2, num) {
+  for (let i = 0; i < num; ++i) {
+    if (buf1[pos1 + i] !== buf2[pos2 + i])
+      return false;
+  }
+  return true;
+}
+
+class SBMH {
+  constructor(needle, cb) {
+    if (typeof cb !== 'function')
+      throw new Error('Missing match callback');
+
+    if (typeof needle === 'string')
+      needle = Buffer.from(needle);
+    else if (!Buffer.isBuffer(needle))
+      throw new Error(`Expected Buffer for needle, got ${typeof needle}`);
+
+    const needleLen = needle.length;
+
+    this.maxMatches = Infinity;
+    this.matches = 0;
+
+    this._cb = cb;
+    this._lookbehindSize = 0;
+    this._needle = needle;
+    this._bufPos = 0;
+
+    this._lookbehind = Buffer.allocUnsafe(needleLen);
+
+    // Initialize occurrence table.
+    this._occ = [
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen, needleLen, needleLen,
+      needleLen, needleLen, needleLen, needleLen
+    ];
+
+    // Populate occurrence table with analysis of the needle, ignoring the last
+    // letter.
+    if (needleLen > 1) {
+      for (let i = 0; i < needleLen - 1; ++i)
+        this._occ[needle[i]] = needleLen - 1 - i;
+    }
+  }
+
+  reset() {
+    this.matches = 0;
+    this._lookbehindSize = 0;
+    this._bufPos = 0;
+  }
+
+  push(chunk, pos) {
+    let result;
+    if (!Buffer.isBuffer(chunk))
+      chunk = Buffer.from(chunk, 'latin1');
+    const chunkLen = chunk.length;
+    this._bufPos = pos || 0;
+    while (result !== chunkLen && this.matches < this.maxMatches)
+      result = feed(this, chunk);
+    return result;
+  }
+
+  destroy() {
+    const lbSize = this._lookbehindSize;
+    if (lbSize)
+      this._cb(false, this._lookbehind, 0, lbSize, false);
+    this.reset();
+  }
+}
+
+function feed(self, data) {
+  const len = data.length;
+  const needle = self._needle;
+  const needleLen = needle.length;
+
+  // Positive: points to a position in `data`
+  //           pos == 3 points to data[3]
+  // Negative: points to a position in the lookbehind buffer
+  //           pos == -2 points to lookbehind[lookbehindSize - 2]
+  let pos = -self._lookbehindSize;
+  const lastNeedleCharPos = needleLen - 1;
+  const lastNeedleChar = needle[lastNeedleCharPos];
+  const end = len - needleLen;
+  const occ = self._occ;
+  const lookbehind = self._lookbehind;
+
+  if (pos < 0) {
+    // Lookbehind buffer is not empty. Perform Boyer-Moore-Horspool
+    // search with character lookup code that considers both the
+    // lookbehind buffer and the current round's haystack data.
+    //
+    // Loop until
+    //   there is a match.
+    // or until
+    //   we've moved past the position that requires the
+    //   lookbehind buffer. In this case we switch to the
+    //   optimized loop.
+    // or until
+    //   the character to look at lies outside the haystack.
+    while (pos < 0 && pos <= end) {
+      const nextPos = pos + lastNeedleCharPos;
+      const ch = (nextPos < 0
+                  ? lookbehind[self._lookbehindSize + nextPos]
+                  : data[nextPos]);
+
+      if (ch === lastNeedleChar
+          && matchNeedle(self, data, pos, lastNeedleCharPos)) {
+        self._lookbehindSize = 0;
+        ++self.matches;
+        if (pos > -self._lookbehindSize)
+          self._cb(true, lookbehind, 0, self._lookbehindSize + pos, false);
+        else
+          self._cb(true, undefined, 0, 0, true);
+
+        return (self._bufPos = pos + needleLen);
+      }
+
+      pos += occ[ch];
+    }
+
+    // No match.
+
+    // There's too few data for Boyer-Moore-Horspool to run,
+    // so let's use a different algorithm to skip as much as
+    // we can.
+    // Forward pos until
+    //   the trailing part of lookbehind + data
+    //   looks like the beginning of the needle
+    // or until
+    //   pos == 0
+    while (pos < 0 && !matchNeedle(self, data, pos, len - pos))
+      ++pos;
+
+    if (pos < 0) {
+      // Cut off part of the lookbehind buffer that has
+      // been processed and append the entire haystack
+      // into it.
+      const bytesToCutOff = self._lookbehindSize + pos;
+
+      if (bytesToCutOff > 0) {
+        // The cut off data is guaranteed not to contain the needle.
+        self._cb(false, lookbehind, 0, bytesToCutOff, false);
+      }
+
+      self._lookbehindSize -= bytesToCutOff;
+      lookbehind.copy(lookbehind, 0, bytesToCutOff, self._lookbehindSize);
+      lookbehind.set(data, self._lookbehindSize);
+      self._lookbehindSize += len;
+
+      self._bufPos = len;
+      return len;
+    }
+
+    // Discard lookbehind buffer.
+    self._cb(false, lookbehind, 0, self._lookbehindSize, false);
+    self._lookbehindSize = 0;
+  }
+
+  pos += self._bufPos;
+
+  const firstNeedleChar = needle[0];
+
+  // Lookbehind buffer is now empty. Perform Boyer-Moore-Horspool
+  // search with optimized character lookup code that only considers
+  // the current round's haystack data.
+  while (pos <= end) {
+    const ch = data[pos + lastNeedleCharPos];
+
+    if (ch === lastNeedleChar
+        && data[pos] === firstNeedleChar
+        && memcmp(needle, 0, data, pos, lastNeedleCharPos)) {
+      ++self.matches;
+      if (pos > 0)
+        self._cb(true, data, self._bufPos, pos, true);
+      else
+        self._cb(true, undefined, 0, 0, true);
+
+      return (self._bufPos = pos + needleLen);
+    }
+
+    pos += occ[ch];
+  }
+
+  // There was no match. If there's trailing haystack data that we cannot
+  // match yet using the Boyer-Moore-Horspool algorithm (because the trailing
+  // data is less than the needle size) then match using a modified
+  // algorithm that starts matching from the beginning instead of the end.
+  // Whatever trailing data is left after running this algorithm is added to
+  // the lookbehind buffer.
+  while (pos < len) {
+    if (data[pos] !== firstNeedleChar
+        || !memcmp(data, pos, needle, 0, len - pos)) {
+      ++pos;
+      continue;
+    }
+    data.copy(lookbehind, 0, pos, len);
+    self._lookbehindSize = len - pos;
+    break;
+  }
+
+  // Everything until `pos` is guaranteed not to contain needle data.
+  if (pos > 0)
+    self._cb(false, data, self._bufPos, pos < len ? pos : len, true);
+
+  self._bufPos = len;
+  return len;
+}
+
+function matchNeedle(self, data, pos, len) {
+  const lb = self._lookbehind;
+  const lbSize = self._lookbehindSize;
+  const needle = self._needle;
+
+  for (let i = 0; i < len; ++i, ++pos) {
+    const ch = (pos < 0 ? lb[lbSize + pos] : data[pos]);
+    if (ch !== needle[i])
+      return false;
+  }
+  return true;
+}
+
+module.exports = SBMH;

node_modules/streamsearch/package.json

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+{
+  "name": "streamsearch",
+  "version": "1.1.0",
+  "author": "Brian White <mscdex@mscdex.net>",
+  "description": "Streaming Boyer-Moore-Horspool searching for node.js",
+  "main": "./lib/sbmh.js",
+  "engines": {
+    "node": ">=10.0.0"
+  },
+  "devDependencies": {
+    "@mscdex/eslint-config": "^1.1.0",
+    "eslint": "^7.32.0"
+  },
+  "scripts": {
+    "test": "node test/test.js",
+    "lint": "eslint --cache --report-unused-disable-directives --ext=.js .eslintrc.js lib test",
+    "lint:fix": "npm run lint -- --fix"
+  },
+  "keywords": [
+    "stream",
+    "horspool",
+    "boyer-moore-horspool",
+    "boyer-moore",
+    "search"
+  ],
+  "licenses": [{
+    "type": "MIT",
+    "url": "http://github.com/mscdex/streamsearch/raw/master/LICENSE"
+  }],
+  "repository": {
+    "type": "git",
+    "url": "http://github.com/mscdex/streamsearch.git"
+  }
+}

node_modules/streamsearch/test/test.js

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+'use strict';
+
+const assert = require('assert');
+
+const StreamSearch = require('../lib/sbmh.js');
+
+[
+  {
+    needle: '\r\n',
+    chunks: [
+      'foo',
+      ' bar',
+      '\r',
+      '\n',
+      'baz, hello\r',
+      '\n world.',
+      '\r\n Node.JS rules!!\r\n\r\n',
+    ],
+    expect: [
+      [false, 'foo'],
+      [false, ' bar'],
+      [ true, null],
+      [false, 'baz, hello'],
+      [ true, null],
+      [false, ' world.'],
+      [ true, null],
+      [ true, ' Node.JS rules!!'],
+      [ true, ''],
+    ],
+  },
+  {
+    needle: '---foobarbaz',
+    chunks: [
+      '---foobarbaz',
+      'asdf',
+      '\r\n',
+      '---foobarba',
+      '---foobar',
+      'ba',
+      '\r\n---foobarbaz--\r\n',
+    ],
+    expect: [
+      [ true, null],
+      [false, 'asdf'],
+      [false, '\r\n'],
+      [false, '---foobarba'],
+      [false, '---foobarba'],
+      [ true, '\r\n'],
+      [false, '--\r\n'],
+    ],
+  },
+].forEach((test, i) => {
+  console.log(`Running test #${i + 1}`);
+  const { needle, chunks, expect } = test;
+
+  const results = [];
+  const ss = new StreamSearch(Buffer.from(needle),
+                              (isMatch, data, start, end) => {
+    if (data)
+      data = data.toString('latin1', start, end);
+    else
+      data = null;
+    results.push([isMatch, data]);
+  });
+
+  for (const chunk of chunks)
+    ss.push(Buffer.from(chunk));
+
+  assert.deepStrictEqual(results, expect);
+});