avancement planning

node_modules/ip-address/dist/common.js

@@ -2,9 +2,11 @@
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.isInSubnet = isInSubnet;
 exports.isCorrect = isCorrect;
+exports.prefixLengthFromMask = prefixLengthFromMask;
 exports.numberToPaddedHex = numberToPaddedHex;
 exports.stringToPaddedHex = stringToPaddedHex;
 exports.testBit = testBit;
+const address_error_1 = require("./address-error");
 function isInSubnet(address) {
     if (this.subnetMask < address.subnetMask) {
         return false;
@@ -25,6 +27,25 @@ function isCorrect(defaultBits) {
         return this.parsedSubnet === String(this.subnetMask);
     };
 }
+/**
+ * Returns the prefix length (number of leading 1 bits) of a contiguous
+ * subnet mask. Throws `AddressError` if the mask is non-contiguous (e.g.
+ * `255.0.255.0`).
+ */
+function prefixLengthFromMask(value, totalBits) {
+    const binary = value.toString(2).padStart(totalBits, '0');
+    if (binary.length > totalBits) {
+        throw new address_error_1.AddressError('Invalid subnet mask.');
+    }
+    const firstZero = binary.indexOf('0');
+    if (firstZero === -1) {
+        return totalBits;
+    }
+    if (binary.slice(firstZero).includes('1')) {
+        throw new address_error_1.AddressError('Invalid subnet mask.');
+    }
+    return firstZero;
+}
 function numberToPaddedHex(number) {
     return number.toString(16).padStart(2, '0');
 }