add osmo_sockaddr_str_is_nonzero()

Often, an IP address of 0.0.0.0 is considered an unset value (for clients
requiring a server address; not for listening on "any").

osmo_sockaddr_str_is_set() does return false when the port is 0, but there is
no simple way to tell whether the IP address is actually set to a server
address.

Add osmo_sockaddr_str_is_nonzero() to return false if:
- the port is zero, or
- the IP address is zero (0.0.0.0 or ::0), or
- the IP address cannot be parsed.

A practical use example: osmo-msc so far accepts an RTP IP address of 0.0.0.0
as valid. I noticed when trying to trigger error handling from a ttcn3 test.
osmo-msc can use this function to reject invalid addresses from MGCP messages.

Related: I53ddb19a70fda3deb906464e1b89c12d9b4c7cbd (osmo-msc)
Change-Id: I73cbcab90cffcdc9a5f8d5281c57c1f87b2c3550
diff --git a/tests/sockaddr_str/sockaddr_str_test.ok b/tests/sockaddr_str/sockaddr_str_test.ok
index d69314d..781e9d1 100644
--- a/tests/sockaddr_str/sockaddr_str_test.ok
+++ b/tests/sockaddr_str/sockaddr_str_test.ok
@@ -2,6 +2,7 @@
 
 { .af = AF_INET, .ip = "1.2.3.4", .port = 5 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc == 0 in_addr=01020304
    -> osmo_sockaddr_str_from_in_addr() rc == 0 { .af = AF_INET, .ip = "1.2.3.4", .port = 5 }
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
@@ -19,6 +20,7 @@
 
 { .af = AF_INET, .ip = "0.0.0.0", .port = 0 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc == 0 in_addr=00000000
    -> osmo_sockaddr_str_from_in_addr() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 0 }
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
@@ -36,6 +38,7 @@
 
 { .af = AF_INET, .ip = "255.255.255.255", .port = 65535 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc == 0 in_addr=ffffffff
    -> osmo_sockaddr_str_from_in_addr() rc == 0 { .af = AF_INET, .ip = "255.255.255.255", .port = 65535 }
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
@@ -53,6 +56,7 @@
 
 { .af = AF_INET, .ip = "0.0.0.256", .port = 1 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -65,6 +69,7 @@
 
 { .af = AF_INET, .ip = "not an ip address", .port = 1 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -77,6 +82,7 @@
 
 { .af = AF_INET6, .ip = "1:2:3::4", .port = 5 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=00010002000300000000000000000004
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "1:2:3::4", .port = 5 }
@@ -92,6 +98,7 @@
 
 { .af = AF_INET6, .ip = "::", .port = 0 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=00000000000000000000000000000000
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "::", .port = 0 }
@@ -107,6 +114,7 @@
 
 { .af = AF_INET6, .ip = "::1", .port = 0 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=00000000000000000000000000000001
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "::1", .port = 0 }
@@ -122,6 +130,7 @@
 
 { .af = AF_INET6, .ip = "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", .port = 65535 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=ffffffffffffffffffffffffffffffff
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", .port = 65535 }
@@ -137,6 +146,7 @@
 
 { .af = AF_INET6, .ip = "FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF", .port = 65535 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=ffffffffffffffffffffffffffffffff
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", .port = 65535 }
@@ -155,6 +165,7 @@
 
 { .af = AF_INET6, .ip = "::fffff", .port = 1 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -167,6 +178,7 @@
 
 { .af = AF_INET6, .ip = "not an ip address", .port = 1 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -179,6 +191,7 @@
 
 { .af = AF_INET6, .ip = "1.2.3.4", .port = 5 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -192,6 +205,7 @@
 
 { .af = AF_INET, .ip = "1:2:3::4", .port = 5 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -205,6 +219,7 @@
 
 { .af = AF_UNSPEC, .ip = "1.2.3.4", .port = 5 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -218,6 +233,7 @@
 
 { .af = AF_INET, .ip = "", .port = 5 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -230,6 +246,7 @@
 
 { .af = AF_INET6, .ip = "", .port = 5 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -242,6 +259,7 @@
 
 { .af = AF_INET, .ip = "1.2.3.4", .port = 0 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc == 0 in_addr=01020304
    -> osmo_sockaddr_str_from_in_addr() rc == 0 { .af = AF_INET, .ip = "1.2.3.4", .port = 0 }
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
@@ -259,6 +277,7 @@
 
 { .af = AF_INET, .ip = "1.2.3:4:5", .port = 0 }
   osmo_sockaddr_str_is_set() = false
+  osmo_sockaddr_str_is_nonzero() = false
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
   osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
@@ -272,6 +291,7 @@
 
 { .af = AF_INET6, .ip = "::1:10.9.8.7", .port = 1 }
   osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = true
   osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
   osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=0000000000000000000000010a090807
    -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "::1:a09:807", .port = 1 }
@@ -286,3 +306,37 @@
    -> osmo_sockaddr_str_from_sockaddr() rc == 0 { .af = AF_INET6, .ip = "::1:a09:807", .port = 1 }
       DIFFERS!
   osmo_sockaddr_str_from_str() rc == 0 { .af = AF_INET6, .ip = "::1:10.9.8.7", .port = 1 }
+
+
+{ .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
+  osmo_sockaddr_str_to_in_addr() rc == 0 in_addr=00000000
+   -> osmo_sockaddr_str_from_in_addr() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_to_in6_addr() rc < 0 in6_addr=00000000000000000000000000000000
+  osmo_sockaddr_str_to_32() rc == 0 uint32_t=0x0
+   -> osmo_sockaddr_str_from_32() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_to_32n() rc == 0 uint32_t=0x0
+   -> osmo_sockaddr_str_from_32n() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_to_sockaddr_in() rc == 0 sockaddr_in=02000005000000000000000000000000
+   -> osmo_sockaddr_str_from_sockaddr_in() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_to_sockaddr_in6() rc < 0 sockaddr_in6=00000000000000000000000000000000000000000000000000000000
+  osmo_sockaddr_str_to_sockaddr() rc == 0 sockaddr_storage=0200000500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+   -> osmo_sockaddr_str_from_sockaddr() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+  osmo_sockaddr_str_from_str() rc == 0 { .af = AF_INET, .ip = "0.0.0.0", .port = 5 }
+
+
+{ .af = AF_INET6, .ip = "::", .port = 5 }
+  osmo_sockaddr_str_is_set() = true
+  osmo_sockaddr_str_is_nonzero() = false
+  osmo_sockaddr_str_to_in_addr() rc < 0 in_addr=00000000
+  osmo_sockaddr_str_to_in6_addr() rc == 0 in6_addr=00000000000000000000000000000000
+   -> osmo_sockaddr_str_from_in6_addr() rc == 0 { .af = AF_INET6, .ip = "::", .port = 5 }
+  osmo_sockaddr_str_to_32() rc < 0 uint32_t=0x0
+  osmo_sockaddr_str_to_32n() rc < 0 uint32_t=0x0
+  osmo_sockaddr_str_to_sockaddr_in() rc < 0 sockaddr_in=00000000000000000000000000000000
+  osmo_sockaddr_str_to_sockaddr_in6() rc == 0 sockaddr_in6=0a000005000000000000000000000000000000000000000000000000
+   -> osmo_sockaddr_str_from_sockaddr_in6() rc == 0 { .af = AF_INET6, .ip = "::", .port = 5 }
+  osmo_sockaddr_str_to_sockaddr() rc == 0 sockaddr_storage=0a00000500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+   -> osmo_sockaddr_str_from_sockaddr() rc == 0 { .af = AF_INET6, .ip = "::", .port = 5 }
+  osmo_sockaddr_str_from_str() rc == 0 { .af = AF_INET6, .ip = "::", .port = 5 }