Mon 21 Jul 22:43:21 CEST 2025

js/sql/sqlite3.js

@@ -0,0 +1,103 @@
+/** JavaScript Sqlite3 Implementation with raw file system access
+ *  (sqlite3C compiled with emscripten from C source)
+ * Usage: 
+ *
+ * db = Database(fileName:string)
+ * db.open()
+ * ret=db.exec('CREATE TABLE ?? (id INTEGER PRIMARY KEY, name TEXT NOT NULL);', tableName)
+ * ret=db.exec('INSERT INTO ?? VALUES (null, ?);', tableName, 'John'))
+ * ret=db.exec('SELECT * FROM ??;', tableName)
+ * -> 
+ *  { code: 0,
+ *     ok: true,
+ *     statement: 'SELECT * FROM "newtable";',
+ *     result: 
+ *      [ { id: '1', name: 'John' }]}
+ *
+ * 
+ *
+ */
+ 
+var sql = require('./sqlite3C.js')
+
+var PTR_SIZE = 4;
+var SQLITE_OK = 0;
+
+var SQLite = {
+  open: sql.cwrap('sqlite3_open', 'number', ['string', 'number']),
+  exec: sql.cwrap('sqlite3_exec', 'number', ['number', 'string', 'number']),
+  close: sql.cwrap('sqlite3_close', 'number', ['number'])
+};
+
+/* output buffer and sqlite3_exec callback function mapping to js */
+var execOutput = [];
+var execCallback = sql.addFunction(function (_, colNumber, valArray, keyArray) {
+  var row = {};
+  for (var offset = 0; offset < colNumber * PTR_SIZE; offset += PTR_SIZE) {
+    var key = sql.UTF8ToString(sql.getValue(keyArray + offset, '*'));
+    var val = sql.UTF8ToString(sql.getValue(valArray + offset, '*'));
+    row[key] = val;
+  }
+  execOutput.push(row);
+});
+
+function escapeText(t) {
+  return String(t).replace(/'/g, "''");
+}
+
+function escapeIdentifier(i) {
+  return String(i).replace(/"/g, '""');
+}
+
+function prepareStatement(statement, parameters) {
+  return String(statement).replace(/\?+/g, function (match) {
+    var param = parameters.shift() || '';
+    switch (match.length) {
+      case 1: return `'${escapeText(param)}'`;
+      case 2: return `"${escapeIdentifier(param)}"`;
+      default: return match;
+    }
+  });
+}
+
+function createResult(code, statement, result) {
+  var o = { code: code, ok: !code };
+  if (statement) o.statement=statement;
+  if (result) o.result=result;
+  return o;
+}
+
+function Database (fileName) {
+  if (!(this instanceof Database)) return new Database (fileName);
+  this.fileName = String(fileName);
+  this.dbPointer = null;
+}
+
+Database.prototype.open = function () {
+  var dbPointer = sql._malloc(PTR_SIZE);
+  var returnValue = SQLite.open(this.fileName, dbPointer);
+  if (returnValue === SQLITE_OK) {
+    this.dbPointer = sql.getValue(dbPointer, '*');
+  }
+  return createResult(returnValue);
+}
+
+Database.prototype.exec = function () {
+  var statement,parameters=[];
+  for(var i in arguments) {
+    if (i=='0') statement=arguments[0];
+    else parameters.push(arguments[i]);
+  }
+  var preparedStatement = prepareStatement(statement, parameters);
+  var returnValue = SQLite.exec(this.dbPointer, preparedStatement, execCallback);
+  var result = returnValue === SQLITE_OK ? execOutput.splice(0) : null;
+  return createResult(returnValue, preparedStatement, result);
+}
+
+Database.prototype.close = function () {
+  var returnValue = SQLite.close(this.dbPointer);
+  return createResult(returnValue);
+}
+
+module.exports = Database
+