add hw2

node_modules/pako/lib/utils/common.js

@@ -0,0 +1,48 @@
+'use strict';
+
+
+const _has = (obj, key) => {
+  return Object.prototype.hasOwnProperty.call(obj, key);
+};
+
+module.exports.assign = function (obj /*from1, from2, from3, ...*/) {
+  const sources = Array.prototype.slice.call(arguments, 1);
+  while (sources.length) {
+    const source = sources.shift();
+    if (!source) { continue; }
+
+    if (typeof source !== 'object') {
+      throw new TypeError(source + 'must be non-object');
+    }
+
+    for (const p in source) {
+      if (_has(source, p)) {
+        obj[p] = source[p];
+      }
+    }
+  }
+
+  return obj;
+};
+
+
+// Join array of chunks to single array.
+module.exports.flattenChunks = (chunks) => {
+  // calculate data length
+  let len = 0;
+
+  for (let i = 0, l = chunks.length; i < l; i++) {
+    len += chunks[i].length;
+  }
+
+  // join chunks
+  const result = new Uint8Array(len);
+
+  for (let i = 0, pos = 0, l = chunks.length; i < l; i++) {
+    let chunk = chunks[i];
+    result.set(chunk, pos);
+    pos += chunk.length;
+  }
+
+  return result;
+};

node_modules/pako/lib/utils/strings.js

@@ -0,0 +1,174 @@
+// String encode/decode helpers
+'use strict';
+
+
+// Quick check if we can use fast array to bin string conversion
+//
+// - apply(Array) can fail on Android 2.2
+// - apply(Uint8Array) can fail on iOS 5.1 Safari
+//
+let STR_APPLY_UIA_OK = true;
+
+try { String.fromCharCode.apply(null, new Uint8Array(1)); } catch (__) { STR_APPLY_UIA_OK = false; }
+
+
+// Table with utf8 lengths (calculated by first byte of sequence)
+// Note, that 5 & 6-byte values and some 4-byte values can not be represented in JS,
+// because max possible codepoint is 0x10ffff
+const _utf8len = new Uint8Array(256);
+for (let q = 0; q < 256; q++) {
+  _utf8len[q] = (q >= 252 ? 6 : q >= 248 ? 5 : q >= 240 ? 4 : q >= 224 ? 3 : q >= 192 ? 2 : 1);
+}
+_utf8len[254] = _utf8len[254] = 1; // Invalid sequence start
+
+
+// convert string to array (typed, when possible)
+module.exports.string2buf = (str) => {
+  if (typeof TextEncoder === 'function' && TextEncoder.prototype.encode) {
+    return new TextEncoder().encode(str);
+  }
+
+  let buf, c, c2, m_pos, i, str_len = str.length, buf_len = 0;
+
+  // count binary size
+  for (m_pos = 0; m_pos < str_len; m_pos++) {
+    c = str.charCodeAt(m_pos);
+    if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) {
+      c2 = str.charCodeAt(m_pos + 1);
+      if ((c2 & 0xfc00) === 0xdc00) {
+        c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00);
+        m_pos++;
+      }
+    }
+    buf_len += c < 0x80 ? 1 : c < 0x800 ? 2 : c < 0x10000 ? 3 : 4;
+  }
+
+  // allocate buffer
+  buf = new Uint8Array(buf_len);
+
+  // convert
+  for (i = 0, m_pos = 0; i < buf_len; m_pos++) {
+    c = str.charCodeAt(m_pos);
+    if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) {
+      c2 = str.charCodeAt(m_pos + 1);
+      if ((c2 & 0xfc00) === 0xdc00) {
+        c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00);
+        m_pos++;
+      }
+    }
+    if (c < 0x80) {
+      /* one byte */
+      buf[i++] = c;
+    } else if (c < 0x800) {
+      /* two bytes */
+      buf[i++] = 0xC0 | (c >>> 6);
+      buf[i++] = 0x80 | (c & 0x3f);
+    } else if (c < 0x10000) {
+      /* three bytes */
+      buf[i++] = 0xE0 | (c >>> 12);
+      buf[i++] = 0x80 | (c >>> 6 & 0x3f);
+      buf[i++] = 0x80 | (c & 0x3f);
+    } else {
+      /* four bytes */
+      buf[i++] = 0xf0 | (c >>> 18);
+      buf[i++] = 0x80 | (c >>> 12 & 0x3f);
+      buf[i++] = 0x80 | (c >>> 6 & 0x3f);
+      buf[i++] = 0x80 | (c & 0x3f);
+    }
+  }
+
+  return buf;
+};
+
+// Helper
+const buf2binstring = (buf, len) => {
+  // On Chrome, the arguments in a function call that are allowed is `65534`.
+  // If the length of the buffer is smaller than that, we can use this optimization,
+  // otherwise we will take a slower path.
+  if (len < 65534) {
+    if (buf.subarray && STR_APPLY_UIA_OK) {
+      return String.fromCharCode.apply(null, buf.length === len ? buf : buf.subarray(0, len));
+    }
+  }
+
+  let result = '';
+  for (let i = 0; i < len; i++) {
+    result += String.fromCharCode(buf[i]);
+  }
+  return result;
+};
+
+
+// convert array to string
+module.exports.buf2string = (buf, max) => {
+  const len = max || buf.length;
+
+  if (typeof TextDecoder === 'function' && TextDecoder.prototype.decode) {
+    return new TextDecoder().decode(buf.subarray(0, max));
+  }
+
+  let i, out;
+
+  // Reserve max possible length (2 words per char)
+  // NB: by unknown reasons, Array is significantly faster for
+  //     String.fromCharCode.apply than Uint16Array.
+  const utf16buf = new Array(len * 2);
+
+  for (out = 0, i = 0; i < len;) {
+    let c = buf[i++];
+    // quick process ascii
+    if (c < 0x80) { utf16buf[out++] = c; continue; }
+
+    let c_len = _utf8len[c];
+    // skip 5 & 6 byte codes
+    if (c_len > 4) { utf16buf[out++] = 0xfffd; i += c_len - 1; continue; }
+
+    // apply mask on first byte
+    c &= c_len === 2 ? 0x1f : c_len === 3 ? 0x0f : 0x07;
+    // join the rest
+    while (c_len > 1 && i < len) {
+      c = (c << 6) | (buf[i++] & 0x3f);
+      c_len--;
+    }
+
+    // terminated by end of string?
+    if (c_len > 1) { utf16buf[out++] = 0xfffd; continue; }
+
+    if (c < 0x10000) {
+      utf16buf[out++] = c;
+    } else {
+      c -= 0x10000;
+      utf16buf[out++] = 0xd800 | ((c >> 10) & 0x3ff);
+      utf16buf[out++] = 0xdc00 | (c & 0x3ff);
+    }
+  }
+
+  return buf2binstring(utf16buf, out);
+};
+
+
+// Calculate max possible position in utf8 buffer,
+// that will not break sequence. If that's not possible
+// - (very small limits) return max size as is.
+//
+// buf[] - utf8 bytes array
+// max   - length limit (mandatory);
+module.exports.utf8border = (buf, max) => {
+
+  max = max || buf.length;
+  if (max > buf.length) { max = buf.length; }
+
+  // go back from last position, until start of sequence found
+  let pos = max - 1;
+  while (pos >= 0 && (buf[pos] & 0xC0) === 0x80) { pos--; }
+
+  // Very small and broken sequence,
+  // return max, because we should return something anyway.
+  if (pos < 0) { return max; }
+
+  // If we came to start of buffer - that means buffer is too small,
+  // return max too.
+  if (pos === 0) { return max; }
+
+  return (pos + _utf8len[buf[pos]] > max) ? pos : max;
+};