From 88e5e66a2a47aeb5880c228ce6a0e9bccb9cdcba Mon Sep 17 00:00:00 2001
From: Philipp Schafft <phschafft@de.loewenfelsen.net>
Date: Sat, 5 Mar 2022 08:42:49 +0000
Subject: [PATCH] Feature: Added support to query address family of a socket

---
 net/sock.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 net/sock.h | 15 +++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/net/sock.c b/net/sock.c
index 1bf20c6..6e8fa8b 100644
--- a/net/sock.c
+++ b/net/sock.c
@@ -961,3 +961,48 @@ sock_t sock_accept(sock_t serversock, char *ip, size_t len)
     return ret;
 }
 
+sock_family_t sock_get_family(sock_t sock)
+{
+    struct sockaddr addr;
+    socklen_t len = sizeof(addr);
+
+    if (getsockname(sock, &addr, &len) != 0)
+        return SOCK_FAMILY__ERROR;
+
+    if (len < sizeof(addr.sa_family))
+        return SOCK_FAMILY__ERROR;
+
+    switch (addr.sa_family) {
+#ifdef AF_UNSPEC
+        case AF_UNSPEC: return SOCK_FAMILY_UNSPEC; break;
+#endif
+#ifdef AF_UNIX
+        case AF_UNIX: return SOCK_FAMILY_UNIX; break;
+#endif
+#ifdef AF_INET
+        case AF_INET: return SOCK_FAMILY_INET4; break;
+#endif
+#ifdef AF_INET6
+        case AF_INET6: return SOCK_FAMILY_INET6; break;
+#endif
+#ifdef AF_DECnet
+        case AF_DECnet: return SOCK_FAMILY_DECnet; break;
+#endif
+    }
+
+    return SOCK_FAMILY__ERROR;
+}
+
+const char * sock_family_to_string(sock_family_t family)
+{
+    switch (family) {
+        case SOCK_FAMILY__ERROR: return "<error>"; break;
+        case SOCK_FAMILY_UNSPEC: return "UNSPEC"; break;
+        case SOCK_FAMILY_UNIX: return "UNIX"; break;
+        case SOCK_FAMILY_INET4: return "INET4"; break;
+        case SOCK_FAMILY_INET6: return "INET6"; break;
+        case SOCK_FAMILY_DECnet: return "DECnet"; break;
+    }
+
+    return "<unknown>";
+}
diff --git a/net/sock.h b/net/sock.h
index e0e3d4f..72648f3 100644
--- a/net/sock.h
+++ b/net/sock.h
@@ -70,6 +70,15 @@ struct iovec
 #define SOCK_ERROR (sock_t)-1
 #define SOCK_TIMEOUT -2
 
+typedef enum {
+    SOCK_FAMILY__ERROR = -1,
+    SOCK_FAMILY_UNSPEC =  0,
+    SOCK_FAMILY_UNIX,
+    SOCK_FAMILY_INET4,
+    SOCK_FAMILY_INET6,
+    SOCK_FAMILY_DECnet
+} sock_family_t;
+
 /* sock connect macro */
 #define sock_connect(h, p) sock_connect_wto(h, p, 0)
 
@@ -102,6 +111,8 @@ struct iovec
 # define sock_listen _mangle(sock_listen)
 # define sock_set_send_buffer _mangle(sock_set_send_buffer)
 # define sock_accept _mangle(sock_accept)
+# define sock_get_family _mangle(sock_get_family)
+# define sock_family_to_string _mangle(sock_family_to_string)
 #endif
 
 /* Misc socket functions */
@@ -144,6 +155,10 @@ sock_t sock_get_server_socket(int port, const char *sinterface);
 int sock_listen(sock_t serversock, int backlog);
 sock_t sock_accept(sock_t serversock, char *ip, size_t len);
 
+/* Socket information */
+sock_family_t sock_get_family(sock_t sock);
+const char * sock_family_to_string(sock_family_t family);
+
 #ifdef _WIN32
 int inet_aton(const char *s, struct in_addr *a);
 #endif