nativenet: Change deprecated sprintf to snprintf

dtool/LocalSetup.cmake

@@ -133,6 +133,7 @@ check_include_file_cxx(dirent.h PHAVE_DIRENT_H)
 check_include_file_cxx(ucontext.h PHAVE_UCONTEXT_H) #TODO doesn't work on OSX, use sys/ucontext.h
 check_include_file_cxx(linux/input.h PHAVE_LINUX_INPUT_H)
 check_include_file_cxx(stdint.h PHAVE_STDINT_H)
+check_include_file_cxx(execinfo.h PHAVE_EXECINFO_H)
 
 # Do we have Posix threads?
 #set(HAVE_POSIX_THREADS ${CMAKE_USE_PTHREADS_INIT})

panda/src/nativenet/socket_address.cxx

@@ -125,13 +125,15 @@ get_ip_port() const {
 
   if (_storage.ss_family == AF_INET) {
     getnameinfo(&_addr, sizeof(sockaddr_in), buf, sizeof(buf), nullptr, 0, NI_NUMERICHOST);
-    sprintf(buf + strlen(buf), ":%hu", get_port());
+    size_t len = strlen(buf);
+    snprintf(buf + len, sizeof(buf) - len, ":%hu", get_port());
 
   } else if (_storage.ss_family == AF_INET6) {
     // Protect the IPv6 address within square brackets.
     buf[0] = '[';
     getnameinfo(&_addr, sizeof(sockaddr_in6), buf + 1, sizeof(buf) - 1, nullptr, 0, NI_NUMERICHOST);
-    sprintf(buf + strlen(buf), "]:%hu", get_port());
+    size_t len = strlen(buf);
+    snprintf(buf + len, sizeof(buf) - len, "]:%hu", get_port());
 
   } else {
     nassert_raise("unsupported address family");