network related functions

1 files changed, 30 insertions, 0 deletions

diff --git a/lisp/network-utils.el b/lisp/network-utils.el
new file mode 100644
index 0000000..3e8a7ae
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+++ b/lisp/network-utils.el
@@ -0,0 +1,30 @@
+;;; network-utils.el --- utils for network stuff -*- lexical-binding: t -*-
+;; Author: Franck Cuny <franck@fcuny.net>
+
+;;; Commentary:
+
+;; commentary
+
+;;; Code:
+
+(defun int-to-ipv4 (integer)
+  "Convert an INTEGER to an IPv4 address string."
+  (format "%d.%d.%d.%d"
+          (logand (ash integer -24) 255)
+          (logand (ash integer -16) 255)
+          (logand (ash integer -8) 255)
+          (logand integer 255)))
+
+(defun ipv4-to-int (ipv4)
+  "Convert an IPV4 address string to an INTEGER."
+  (let ((octets (mapcar #'string-to-number (split-string ipv4 "\\."))))
+    (if (= (length octets) 4)
+        (+ (ash (nth 0 octets) 24)
+           (ash (nth 1 octets) 16)
+           (ash (nth 2 octets) 8)
+           (nth 3 octets))
+      (error "Invalid IPv4 address format"))))
+
+(provide 'network-utils)
+
+;;; network-utils.el ends here