add osmo_sockaddr_to_str_and_uint()

This came from osmo-bsc refactoring patch I82e3f918295daa83274a4cf803f046979f284366
https://gerrit.osmocom.org/#/c/osmo-bsc/+/9671/6/src/osmo-bsc/gsm_data.c@1708

Add regression test in utils_test.c.

Change-Id: I1f2918418c38918c5ac70acaa51a47adfca12b5e

4 files changed, 148 insertions, 0 deletions

diff --git a/include/osmocom/core/socket.h b/include/osmocom/core/socket.h
index 47d9f308..20515b99 100644
--- a/include/osmocom/core/socket.h
+++ b/include/osmocom/core/socket.h
@@ -44,6 +44,9 @@ int osmo_sock_init_sa(struct sockaddr *ss, uint16_t type,
 
 int osmo_sockaddr_is_local(struct sockaddr *addr, unsigned int addrlen);
 
+unsigned int osmo_sockaddr_to_str_and_uint(char *addr, unsigned int addr_len, uint16_t *port,
+					   const struct sockaddr *sa);
+
 int osmo_sock_unix_init(uint16_t type, uint8_t proto,
 			const char *socket_path, unsigned int flags);
 
diff --git a/src/socket.c b/src/socket.c
index cd73f17c..04058474 100644
--- a/src/socket.c
+++ b/src/socket.c
@@ -35,6 +35,7 @@
 #include <osmocom/core/select.h>
 #include <osmocom/core/socket.h>
 #include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
 
 #include <sys/ioctl.h>
 #include <sys/socket.h>
@@ -553,6 +554,25 @@ int osmo_sockaddr_is_local(struct sockaddr *addr, unsigned int addrlen)
 	return 0;
 }
 
+/*! Convert sockaddr to IP address as char string and port as uint16_t.
+ *  \param[out] addr  String buffer to write IP address to, or NULL.
+ *  \param[out] addr_len  Size of \a addr.
+ *  \param[out] port  Pointer to uint16_t to write the port number to, or NULL.
+ *  \param[in] sa  Sockaddr to convert.
+ *  \returns the required string buffer size, like osmo_strlcpy(), or 0 if \a addr is NULL.
+ */
+unsigned int osmo_sockaddr_to_str_and_uint(char *addr, unsigned int addr_len, uint16_t *port,
+					   const struct sockaddr *sa)
+{
+	const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
+
+	if (port)
+		*port = ntohs(sin->sin_port);
+	if (addr)
+		return osmo_strlcpy(addr, inet_ntoa(sin->sin_addr), addr_len);
+	return 0;
+}
+
 /*! Initialize a unix domain socket (including bind/connect)
  *  \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM
  *  \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP
diff --git a/tests/utils/utils_test.c b/tests/utils/utils_test.c
index 84964f57..a146190d 100644
--- a/tests/utils/utils_test.c
+++ b/tests/utils/utils_test.c
@@ -24,10 +24,13 @@
 
 #include <osmocom/core/logging.h>
 #include <osmocom/core/utils.h>
+#include <osmocom/core/socket.h>
 
 #include <stdio.h>
 #include <ctype.h>
 #include <time.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
 
 static void hexdump_test(void)
 {
@@ -446,6 +449,117 @@ static void isqrt_test(void)
 	}
 }
 
+
+struct osmo_sockaddr_to_str_and_uint_test_case {
+	uint16_t port;
+	bool omit_port;
+	const char *addr;
+	unsigned int addr_len;
+	bool omit_addr;
+	unsigned int expect_rc;
+	const char *expect_returned_addr;
+};
+
+struct osmo_sockaddr_to_str_and_uint_test_case osmo_sockaddr_to_str_and_uint_test_data[] = {
+	{
+		.port = 0,
+		.addr = "0.0.0.0",
+		.addr_len = 20,
+		.expect_rc = 7,
+	},
+	{
+		.port = 65535,
+		.addr = "255.255.255.255",
+		.addr_len = 20,
+		.expect_rc = 15,
+	},
+	{
+		.port = 1234,
+		.addr = "234.23.42.123",
+		.addr_len = 20,
+		.expect_rc = 13,
+	},
+	{
+		.port = 1234,
+		.addr = "234.23.42.123",
+		.addr_len = 10,
+		.expect_rc = 13,
+		.expect_returned_addr = "234.23.42",
+	},
+	{
+		.port = 1234,
+		.omit_port = true,
+		.addr = "234.23.42.123",
+		.addr_len = 20,
+		.expect_rc = 13,
+	},
+	{
+		.port = 1234,
+		.addr = "234.23.42.123",
+		.omit_addr = true,
+		.expect_rc = 0,
+		.expect_returned_addr = "",
+	},
+	{
+		.port = 1234,
+		.addr = "234.23.42.123",
+		.addr_len = 0,
+		.expect_rc = 13,
+		.expect_returned_addr = "",
+	},
+	{
+		.port = 1234,
+		.addr = "234.23.42.123",
+		.omit_port = true,
+		.omit_addr = true,
+		.expect_rc = 0,
+		.expect_returned_addr = "",
+	},
+};
+
+static void osmo_sockaddr_to_str_and_uint_test(void)
+{
+	int i;
+	printf("\n%s\n", __func__);
+
+	for (i = 0; i < ARRAY_SIZE(osmo_sockaddr_to_str_and_uint_test_data); i++) {
+		struct osmo_sockaddr_to_str_and_uint_test_case *t =
+			&osmo_sockaddr_to_str_and_uint_test_data[i];
+
+		struct sockaddr_in sin = {
+			.sin_family = AF_INET,
+			.sin_port = htons(t->port),
+		};
+		inet_aton(t->addr, &sin.sin_addr);
+
+		char addr[20] = {};
+		uint16_t port = 0;
+		unsigned int rc;
+
+		rc = osmo_sockaddr_to_str_and_uint(
+			t->omit_addr? NULL : addr, t->addr_len,
+			t->omit_port? NULL : &port,
+			(const struct sockaddr*)&sin);
+
+		printf("[%d] %s:%u%s%s addr_len=%u --> %s:%u rc=%u\n",
+		       i,
+		       t->addr ? : "-",
+		       t->port,
+		       t->omit_addr ? " (omit addr)" : "",
+		       t->omit_port ? " (omit port)" : "",
+		       t->addr_len,
+		       addr, port, rc);
+		if (rc != t->expect_rc)
+			printf("ERROR: Expected rc = %u\n", t->expect_rc);
+		if (!t->expect_returned_addr)
+			t->expect_returned_addr = t->addr;
+		if (strcmp(t->expect_returned_addr, addr))
+			printf("ERROR: Expected addr = '%s'\n", t->expect_returned_addr);
+		if (!t->omit_port && port != t->port)
+			printf("ERROR: Expected port = %u\n", t->port);
+	}
+}
+
 int main(int argc, char **argv)
 {
 	static const struct log_info log_info = {};
@@ -459,5 +573,6 @@ int main(int argc, char **argv)
 	str_escape_test();
 	str_quote_test();
 	isqrt_test();
+	osmo_sockaddr_to_str_and_uint_test();
 	return 0;
 }
diff --git a/tests/utils/utils_test.ok b/tests/utils/utils_test.ok
index ea9216f0..b158bf7b 100644
--- a/tests/utils/utils_test.ok
+++ b/tests/utils/utils_test.ok
@@ -139,3 +139,13 @@ NOT passed through. '"printable"'
 'NULL'
 
 Testing integer square-root
+
+osmo_sockaddr_to_str_and_uint_test
+[0] 0.0.0.0:0 addr_len=20 --> 0.0.0.0:0 rc=7
+[1] 255.255.255.255:65535 addr_len=20 --> 255.255.255.255:65535 rc=15
+[2] 234.23.42.123:1234 addr_len=20 --> 234.23.42.123:1234 rc=13
+[3] 234.23.42.123:1234 addr_len=10 --> 234.23.42:1234 rc=13
+[4] 234.23.42.123:1234 (omit port) addr_len=20 --> 234.23.42.123:0 rc=13
+[5] 234.23.42.123:1234 (omit addr) addr_len=0 --> :1234 rc=0
+[6] 234.23.42.123:1234 addr_len=0 --> :1234 rc=13
+[7] 234.23.42.123:1234 (omit addr) (omit port) addr_len=0 --> :0 rc=0