reduce thread-unsafe use of static variables

- rework ip_ntoa() to avoid use of static variables
- rework sort_client_list() to avoid use of static variables
- move static 'lastdump' into Messenger struct
- rework ID2String() to avoid use of static variables; rename to id_to_string()
- fetch_broadcast_info(): attempt to mitigate risks from concurrent execution
- current_time_monotonic(): attempt to mitigate risks from concurrent execution
- comment on non-thread-safety of unix_time_update

1 files changed, 8 insertions, 3 deletions

diff --git a/auto_tests/network_test.c b/auto_tests/network_test.c
index ca918778..2ce6d0b5 100644
--- a/auto_tests/network_test.c
+++ b/auto_tests/network_test.c
@@ -36,7 +36,8 @@ START_TEST(test_addr_resolv_localhost)
 
     if (res > 0) {
         ck_assert_msg(ip.family == AF_INET, "Expected family AF_INET, got %u.", ip.family);
-        ck_assert_msg(ip.ip4.uint32 == htonl(0x7F000001), "Expected 127.0.0.1, got %s.", inet_ntoa(ip.ip4.in_addr));
+        ck_assert_msg(ip.ip4.uint32 == htonl(0x7F000001), "Expected 127.0.0.1, got %s.",
+                      inet_ntoa(ip.ip4.in_addr));
     }
 
     ip_init(&ip, 1); // ipv6enabled = 1
@@ -50,8 +51,10 @@ START_TEST(test_addr_resolv_localhost)
     ck_assert_msg(res > 0, "Resolver failed: %u, %s (%x, %x)", errno, strerror(errno));
 
     if (res > 0) {
+        char ip_str[IP_NTOA_LEN];
         ck_assert_msg(ip.family == AF_INET6, "Expected family AF_INET6 (%u), got %u.", AF_INET6, ip.family);
-        ck_assert_msg(!memcmp(&ip.ip6, &in6addr_loopback, sizeof(IP6)), "Expected ::1, got %s.", ip_ntoa(&ip));
+        ck_assert_msg(!memcmp(&ip.ip6, &in6addr_loopback, sizeof(IP6)), "Expected ::1, got %s.",
+                      ip_ntoa(&ip, ip_str, sizeof(ip_str)));
     }
 
     if (!localhost_split) {
@@ -63,8 +66,10 @@ START_TEST(test_addr_resolv_localhost)
         ck_assert_msg(res > 0, "Resolver failed: %u, %s (%x, %x)", errno, strerror(errno));
 
         if (res > 0) {
+            char ip_str[IP_NTOA_LEN];
             ck_assert_msg(ip.family == AF_INET6, "Expected family AF_INET6 (%u), got %u.", AF_INET6, ip.family);
-            ck_assert_msg(!memcmp(&ip.ip6, &in6addr_loopback, sizeof(IP6)), "Expected ::1, got %s.", ip_ntoa(&ip));
+            ck_assert_msg(!memcmp(&ip.ip6, &in6addr_loopback, sizeof(IP6)), "Expected ::1, got %s.",
+                          ip_ntoa(&ip, ip_str, sizeof(ip_str)));
 
             ck_assert_msg(extra.family == AF_INET, "Expected family AF_INET (%u), got %u.", AF_INET, extra.family);
             ck_assert_msg(extra.ip4.uint32 == htonl(0x7F000001), "Expected 127.0.0.1, got %s.", inet_ntoa(extra.ip4.in_addr));