From 022bb697820d0ddcfe70918a63c4fcfd9558df87 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Mon, 2 Jun 2025 11:29:52 +0300
Subject: [PATCH] LibC: Implement inet_aton

This is not POSIX but IMO it makes sense to have the counter part to
inet_ntoa
---
 userspace/libraries/LibC/arpa/inet.cpp       | 51 ++++++++++++--------
 userspace/libraries/LibC/include/arpa/inet.h |  1 +
 2 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/userspace/libraries/LibC/arpa/inet.cpp b/userspace/libraries/LibC/arpa/inet.cpp
index 15e98950a7..938f35f39d 100644
--- a/userspace/libraries/LibC/arpa/inet.cpp
+++ b/userspace/libraries/LibC/arpa/inet.cpp
@@ -27,28 +27,10 @@ uint16_t ntohs(uint16_t netshort)
 
 in_addr_t inet_addr(const char* cp)
 {
-	uint32_t a, b, c, d, n;
-	const int ret = sscanf(cp, "%i%n.%i%n.%i%n.%i%n",
-		&a, &n, &b, &n, &c, &n, &d, &n
-	);
-
-	if (ret < 1 || ret > 4 || cp[n] != '\0')
+	in_addr addr;
+	if (inet_aton(cp, &addr) == 0)
 		return INADDR_NONE;
-	if (ret == 1 && (a > 0xFFFFFFFF))
-		return INADDR_NONE;
-	if (ret == 2 && (a > 0xFF || b > 0xFFFFFF))
-		return INADDR_NONE;
-	if (ret == 3 && (a > 0xFF || b > 0xFF || c > 0xFFFF))
-		return INADDR_NONE;
-	if (ret == 4 && (a > 0xFF || b > 0xFF || c > 0xFF || d > 0xFF))
-		return INADDR_NONE;
-
-	uint32_t result = 0;
-	result |= (ret == 1) ? a : a << 24;
-	result |= (ret == 2) ? b : b << 16;
-	result |= (ret == 3) ? c : c <<  8;
-	result |= (ret == 4) ? d : d <<  0;
-	return htonl(result);
+	return addr.s_addr;
 }
 
 char* inet_ntoa(struct in_addr in)
@@ -64,6 +46,33 @@ char* inet_ntoa(struct in_addr in)
 	return buffer;
 }
 
+int inet_aton(const char* cp, struct in_addr* inp)
+{
+	uint32_t a, b, c, d, n;
+	const int ret = sscanf(cp, "%i%n.%i%n.%i%n.%i%n",
+		&a, &n, &b, &n, &c, &n, &d, &n
+	);
+
+	if (ret < 1 || ret > 4 || cp[n] != '\0')
+		return 0;
+	if (ret == 1 && (a > 0xFFFFFFFF))
+		return 0;
+	if (ret == 2 && (a > 0xFF || b > 0xFFFFFF))
+		return 0;
+	if (ret == 3 && (a > 0xFF || b > 0xFF || c > 0xFFFF))
+		return 0;
+	if (ret == 4 && (a > 0xFF || b > 0xFF || c > 0xFF || d > 0xFF))
+		return 0;
+
+	uint32_t result = 0;
+	result |= (ret == 1) ? a : a << 24;
+	result |= (ret == 2) ? b : b << 16;
+	result |= (ret == 3) ? c : c <<  8;
+	result |= (ret == 4) ? d : d <<  0;
+	inp->s_addr = htonl(result);
+	return 1;
+}
+
 const char* inet_ntop(int af, const void* __restrict src, char* __restrict dst, socklen_t size)
 {
 	if (af == AF_INET)
diff --git a/userspace/libraries/LibC/include/arpa/inet.h b/userspace/libraries/LibC/include/arpa/inet.h
index 5db471ce22..674754ee7e 100644
--- a/userspace/libraries/LibC/include/arpa/inet.h
+++ b/userspace/libraries/LibC/include/arpa/inet.h
@@ -11,6 +11,7 @@ __BEGIN_DECLS
 #include <bits/types/socklen_t.h>
 
 in_addr_t	inet_addr(const char* cp);
+int			inet_aton(const char* cp, struct in_addr* inp);
 char*		inet_ntoa(struct in_addr in);
 const char*	inet_ntop(int af, const void* __restrict src, char* __restrict dst, socklen_t size);
 int			inet_pton(int af, const char* __restrict src, void* __restrict dst);