1 files changed, 140 insertions, 0 deletions
diff --git a/node_modules/mysql2/lib/packets/column_definition.js b/node_modules/mysql2/lib/packets/column_definition.js
new file mode 100644
index 0000000..29df846
--- /dev/null
+++ b/node_modules/mysql2/lib/packets/column_definition.js
@@ -0,0 +1,140 @@
+'use strict';
+
+const Packet = require('../packets/packet');
+const StringParser = require('../parsers/string');
+const CharsetToEncoding = require('../constants/charset_encodings.js');
+
+const fields = ['catalog', 'schema', 'table', 'orgTable', 'name', 'orgName'];
+
+// creating JS string is relatively expensive (compared to
+// reading few bytes from buffer) because all string properties
+// except for name are unlikely to be used we postpone
+// string conversion until property access
+//
+// TODO: watch for integration benchmarks (one with real network buffer)
+// there could be bad side effect as keeping reference to a buffer makes it
+// sit in the memory longer (usually until final .query() callback)
+// Latest v8 perform much better in regard to bufferer -> string conversion,
+// at some point of time this optimisation might become unnecessary
+// see https://github.com/sidorares/node-mysql2/pull/137
+//
+class ColumnDefinition {
+  constructor(packet, clientEncoding) {
+    this._buf = packet.buffer;
+    this._clientEncoding = clientEncoding;
+    this._catalogLength = packet.readLengthCodedNumber();
+    this._catalogStart = packet.offset;
+    packet.offset += this._catalogLength;
+    this._schemaLength = packet.readLengthCodedNumber();
+    this._schemaStart = packet.offset;
+    packet.offset += this._schemaLength;
+    this._tableLength = packet.readLengthCodedNumber();
+    this._tableStart = packet.offset;
+    packet.offset += this._tableLength;
+    this._orgTableLength = packet.readLengthCodedNumber();
+    this._orgTableStart = packet.offset;
+    packet.offset += this._orgTableLength;
+    // name is always used, don't make it lazy
+    const _nameLength = packet.readLengthCodedNumber();
+    const _nameStart = packet.offset;
+    packet.offset += _nameLength;
+    this._orgNameLength = packet.readLengthCodedNumber();
+    this._orgNameStart = packet.offset;
+    packet.offset += this._orgNameLength;
+    packet.skip(1); //  length of the following fields (always 0x0c)
+    this.characterSet = packet.readInt16();
+    this.encoding = CharsetToEncoding[this.characterSet];
+    this.name = StringParser.decode(
+      this._buf,
+      this.encoding === 'binary' ? this._clientEncoding : this.encoding,
+      _nameStart, 
+      _nameStart + _nameLength
+    );
+    this.columnLength = packet.readInt32();
+    this.columnType = packet.readInt8();
+    this.flags = packet.readInt16();
+    this.decimals = packet.readInt8();
+  }
+
+  inspect() {
+    return {
+      catalog: this.catalog,
+      schema: this.schema,
+      name: this.name,
+      orgName: this.orgName,
+      table: this.table,
+      orgTable: this.orgTable,
+      characterSet: this.characterSet,
+      columnLength: this.columnLength,
+      columnType: this.columnType,
+      flags: this.flags,
+      decimals: this.decimals
+    };
+  }
+
+  static toPacket(column, sequenceId) {
+    let length = 17; // = 4 padding + 1 + 12 for the rest
+    fields.forEach(field => {
+      length += Packet.lengthCodedStringLength(
+        column[field],
+        CharsetToEncoding[column.characterSet]
+      );
+    });
+    const buffer = Buffer.allocUnsafe(length);
+
+    const packet = new Packet(sequenceId, buffer, 0, length);
+    function writeField(name) {
+      packet.writeLengthCodedString(
+        column[name],
+        CharsetToEncoding[column.characterSet]
+      );
+    }
+    packet.offset = 4;
+    fields.forEach(writeField);
+    packet.writeInt8(0x0c);
+    packet.writeInt16(column.characterSet);
+    packet.writeInt32(column.columnLength);
+    packet.writeInt8(column.columnType);
+    packet.writeInt16(column.flags);
+    packet.writeInt8(column.decimals);
+    packet.writeInt16(0); // filler
+    return packet;
+  }
+
+  // node-mysql compatibility: alias "db" to "schema"
+  get db() {
+    return this.schema;
+  }
+}
+
+const addString = function(name) {
+  Object.defineProperty(ColumnDefinition.prototype, name, {
+    get: function() {
+      const start = this[`_${name}Start`];
+      const end = start + this[`_${name}Length`];
+      const val = StringParser.decode(
+        this._buf,
+        this.encoding === 'binary' ? this._clientEncoding : this.encoding,
+        start, 
+        end
+      );
+      
+      Object.defineProperty(this, name, {
+        value: val,
+        writable: false,
+        configurable: false,
+        enumerable: false
+      });
+
+      return val;
+    }
+  });
+};
+
+addString('catalog');
+addString('schema');
+addString('table');
+addString('orgTable');
+addString('orgName');
+
+module.exports = ColumnDefinition;