Created
October 11, 2014 17:58
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Test \u0000 string truncation in Web SQL
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| <html> | |
| <body> | |
| <h1>Test \u0000 string truncation in Web SQL</h1> | |
| <p>Details <a href='https://github.com/pouchdb/pouchdb/pull/1731#issuecomment-38622342'>in this PouchDB bug</a>.</p> | |
| <pre id="display"></pre> | |
| <script src="index.js"></script> | |
| </body> | |
| </html> |
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| (function() { | |
| 'use strict'; | |
| var display = document.getElementById('display'); | |
| function log(str) { | |
| display.innerHTML += '\n' + str; | |
| } | |
| function decodeUtf8(str) { | |
| return decodeURIComponent(window.escape(str)); | |
| } | |
| function parseHexString(str, encoding) { | |
| var result = ''; | |
| var charWidth = encoding === 'UTF-8' ? 2 : 4; | |
| for (var i = 0, len = str.length; i < len; i += charWidth) { | |
| var substring = str.substring(i, i + charWidth); | |
| if (charWidth === 4) { // UTF-16, twiddle the bits | |
| substring = substring.substring(2, 4) + substring.substring(0, 2); | |
| } | |
| result += String.fromCharCode(parseInt(substring, 16)); | |
| } | |
| result = encoding === 'UTF-8' ? decodeUtf8(result) : result; | |
| return result; | |
| } | |
| var db = openDatabase('Demo', "1.0", "Demo", 5000000); | |
| db.transaction(function (tx) { | |
| var sql = 'SELECT ? AS mystring'; | |
| var sqlArgs = ['foo\u0000bar']; | |
| log('executing "' + sql + '" with args ' + JSON.stringify(sqlArgs)); | |
| tx.executeSql(sql, sqlArgs, function (tx, res) { | |
| var mystring = res.rows.item(0).mystring; | |
| log("string returned: " + JSON.stringify(mystring)); | |
| log("if the bug is present, then it will be cut off after \\u0000"); | |
| log('\nokay, let\'s try hex() instead'); | |
| sql = 'SELECT hex(?) AS hex'; | |
| sqlArgs = ['foo\u0000bar']; | |
| log('executing "' + sql + '" with args ' + JSON.stringify(sqlArgs)); | |
| tx.executeSql(sql, sqlArgs, function (tx, res) { | |
| var hex = res.rows.item(0).hex; | |
| log("string returned: " + JSON.stringify(hex)); | |
| log("\nlet's parse that hex..."); | |
| // can determine the DB's encoding based on the length of | |
| // the hex returned. pre-7.1 Safari is UTF-16. | |
| var encoding = hex.length === 14 ? 'UTF-8' : 'UTF-16'; | |
| var parsed = parseHexString(hex, encoding); | |
| log('parsed string is: ' + JSON.stringify(parsed)); | |
| log("that's funny, the whole string is there now!"); | |
| }); | |
| }); | |
| }, function(err) { | |
| log('unexpected error: ' + err.message); | |
| }, function () { | |
| }); | |
| })(); |
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