std-aux/glib-aux: minor cleanup of nm_ip_addr_*()/nm_utils_addr_family_*()

- let nm_ip_addr_is_null() work for unaligned addresses.

- drop redundant nm_assert_addr_family().

- move code around.

src/libnm-glib-aux/nm-shared-utils.h

@@ -247,7 +247,6 @@ extern const NMIPAddr nm_ip_addr_zero;
 static inline int
 nm_ip_addr_cmp(int addr_family, gconstpointer a, gconstpointer b)
 {
-    nm_assert_addr_family(addr_family);
     nm_assert(a);
     nm_assert(b);
 
@@ -264,20 +263,27 @@ static inline gboolean
 nm_ip_addr_is_null(int addr_family, gconstpointer addr)
 {
     nm_assert(addr);
-    if (addr_family == AF_INET6)
-        return IN6_IS_ADDR_UNSPECIFIED((const struct in6_addr *) addr);
-    nm_assert(addr_family == AF_INET);
-    return ((const struct in_addr *) addr)->s_addr == 0;
+
+    if (NM_IS_IPv4(addr_family)) {
+        in_addr_t t;
+
+        /* also for in_addr_t type (AF_INET), we accept that the pointer might
+         * be unaligned. */
+        memcpy(&t, addr, sizeof(t));
+        return t == 0;
+    }
+
+    return IN6_IS_ADDR_UNSPECIFIED((const struct in6_addr *) addr);
 }
 
 static inline void
 nm_ip_addr_set(int addr_family, gpointer dst, gconstpointer src)
 {
-    nm_assert_addr_family(addr_family);
     nm_assert(dst);
     nm_assert(src);
 
-    memcpy(dst, src, NM_IS_IPv4(addr_family) ? sizeof(in_addr_t) : sizeof(struct in6_addr));
+    /* this MUST use memcpy() (or similar means) to support unaligned src/dst pointers. */
+    memcpy(dst, src, nm_utils_addr_family_to_size(addr_family));
 }
 
 static inline NMIPAddr

src/libnm-std-aux/nm-std-aux.h

@@ -1060,6 +1060,18 @@ nm_utils_addr_family_to_char(int addr_family)
     return '?';
 }
 
+#define nm_assert_addr_family(addr_family) \
+    nm_assert(NM_IN_SET((addr_family), NM_AF_INET, NM_AF_INET6))
+
+#define NM_IS_IPv4(addr_family)                 \
+    ({                                          \
+        const int _addr_family = (addr_family); \
+                                                \
+        nm_assert_addr_family(_addr_family);    \
+                                                \
+        (_addr_family == NM_AF_INET);           \
+    })
+
 static inline size_t
 nm_utils_addr_family_to_size(int addr_family)
 {
@@ -1069,8 +1081,7 @@ nm_utils_addr_family_to_size(int addr_family)
     case NM_AF_INET6:
         return NM_AF_INET6_SIZE;
     }
-    nm_assert_not_reached();
-    return 0;
+    return nm_assert_unreachable_val(0);
 }
 
 static inline int
@@ -1085,16 +1096,4 @@ nm_utils_addr_family_from_size(size_t len)
     return NM_AF_UNSPEC;
 }
 
-#define nm_assert_addr_family(addr_family) \
-    nm_assert(NM_IN_SET((addr_family), NM_AF_INET, NM_AF_INET6))
-
-#define NM_IS_IPv4(addr_family)                 \
-    ({                                          \
-        const int _addr_family = (addr_family); \
-                                                \
-        nm_assert_addr_family(_addr_family);    \
-                                                \
-        (_addr_family == NM_AF_INET);           \
-    })
-
 #endif /* __NM_STD_AUX_H__ */