add

2026-01-17 19:08:14 +08:00
parent 7073975960
commit 71def0f3c7
1409 changed files with 101928 additions and 43 deletions
@@ -0,0 +1,49 @@
+"use strict";
+
+(function() {
+
+// ARMv6 (Raspberry Pi) has bug in bitwise operations
+// https://code.google.com/p/v8/issues/detail?id=3757
+// https://github.com/alexeyten/qr-image/issues/13
+if (process.arch === 'arm') {
+    module.exports = require('./crc32buffer');
+    return;
+}
+
+var crc_table = [];
+
+(function() {
+    for (var n = 0; n < 256; n++) {
+        var c = n;
+        for (var k = 0; k < 8; k++) {
+            if (c & 1) {
+                c = 0xedb88320 ^ (c >>> 1);
+            } else {
+                c = c >>> 1;
+            }
+        }
+        crc_table[n] = c >>> 0;
+    }
+})();
+
+function update(c, buf) {
+    var l = buf.length;
+    for (var n = 0; n < l; n++) {
+        c = crc_table[(c ^ buf[n]) & 0xff] ^ (c >>> 8);
+    }
+    return c;
+}
+
+function crc32(/* arguments */) {
+    var l = arguments.length;
+    var c = -1;
+    for (var i = 0; i < l; i++) {
+        c = update(c, new Buffer(arguments[i]));
+    }
+    c = (c ^ -1) >>> 0;
+    return c;
+}
+
+module.exports = crc32;
+    
+})();