Minor cleanups for server-name fix (Bug#24218)

* lisp/server.el (server--external-socket-initialized): Rename
from server-external-socket-initialised, since it should be
private and Emacs uses American spelling.  All uses changed.
* src/emacs.c, src/lisp.h: Revert previous changes, as the
initialization is now done in src/process.c, which already
includes the relevant files.
* src/process.c (union u_sockaddr): Move decl to top level.
(external_sock_name, Fget_external_sockname): Remove, replacing
with Vinternal__external_sockname.  All uses changed.
(init_process_emacs): Deduce socket name ourselves rather than
have main.c do it.  Use conv_sockaddr_to_lisp instead of doing
it by hand.  Conditionalize it on HAVE_GETSOCKNAME.

3 files changed, 34 insertions, 42 deletions

diff --git a/src/emacs.c b/src/emacs.c
index c423faf6c0d..8ea61b71fb7 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -60,7 +60,6 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #ifdef HAVE_LIBSYSTEMD
 # include <systemd/sd-daemon.h>
 # include <sys/socket.h>
-# include <sys/un.h>
 #endif
 
 #ifdef HAVE_WINDOW_SYSTEM
@@ -1003,7 +1002,6 @@ main (int argc, char **argv)
 
 
   int sockfd = -1;
-  char *sockname = NULL;
 
   if (argmatch (argv, argc, "-fg-daemon", "--fg-daemon", 10, NULL, &skip_args)
       || argmatch (argv, argc, "-fg-daemon", "--fg-daemon", 10, &dname_arg, &skip_args))
@@ -1063,16 +1061,8 @@ main (int argc, char **argv)
                   "Try 'Accept=false' in the Emacs socket unit file.\n"));
       else if (systemd_socket == 1
                && (0 < sd_is_socket (SD_LISTEN_FDS_START,
-                                    AF_UNIX, SOCK_STREAM, 1)))
-        {
-          struct sockaddr_un sockaddr;
-          socklen_t sockaddr_sz = sizeof(sockaddr);
-
-          sockfd = SD_LISTEN_FDS_START;
-
-          if (!getsockname(sockfd, &sockaddr, &sockaddr_sz))
-            sockname = strdup(sockaddr.sun_path);
-        }
+                                     AF_UNSPEC, SOCK_STREAM, 1)))
+        sockfd = SD_LISTEN_FDS_START;
 #endif /* HAVE_LIBSYSTEMD */
 
 #ifdef USE_GTK
@@ -1670,7 +1660,7 @@ Using an Emacs configured with --with-x-toolkit=lucid does not have this problem
   /* This can create a thread that may call getenv, so it must follow
      all calls to putenv and setenv.  Also, this sets up
      add_keyboard_wait_descriptor, which init_display uses.  */
-  init_process_emacs (sockfd, sockname);
+  init_process_emacs (sockfd);
 
   init_keyboard ();     /* This too must precede init_sys_modes.  */
   if (!noninteractive)
diff --git a/src/lisp.h b/src/lisp.h
index 0bd0e5e53cf..a7f0a1d78ff 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -4316,7 +4316,7 @@ extern void delete_keyboard_wait_descriptor (int);
 extern void add_gpm_wait_descriptor (int);
 extern void delete_gpm_wait_descriptor (int);
 #endif
-extern void init_process_emacs (int, char *);
+extern void init_process_emacs (int);
 extern void syms_of_process (void);
 extern void setup_process_coding_systems (Lisp_Object);
 
diff --git a/src/process.c b/src/process.c
index 405c06db46d..8396a939c2b 100644
--- a/src/process.c
+++ b/src/process.c
@@ -160,6 +160,18 @@ static bool kbd_is_on_hold;
    when exiting.  */
 bool inhibit_sentinels;
 
+union u_sockaddr
+{
+  struct sockaddr sa;
+  struct sockaddr_in in;
+#ifdef AF_INET6
+  struct sockaddr_in6 in6;
+#endif
+#ifdef HAVE_LOCAL_SOCKETS
+  struct sockaddr_un un;
+#endif
+};
+
 #ifdef subprocesses
 
 #ifndef SOCK_CLOEXEC
@@ -276,10 +288,6 @@ static int max_desc;
    the file descriptor of a socket that is already bound.  */
 static int external_sock_fd;
 
-/* The name (path) of the socket that was passed to Emacs, when
-   `external_sock_fd' is not -1.  */
-static const char *external_sock_name = NULL;
-
 /* Indexed by descriptor, gives the process (if any) for that descriptor.  */
 static Lisp_Object chan_process[FD_SETSIZE];
 static void wait_for_socket_fds (Lisp_Object, char const *);
@@ -4677,16 +4685,7 @@ server_accept_connection (Lisp_Object server, int channel)
   struct Lisp_Process *ps = XPROCESS (server);
   struct Lisp_Process *p;
   int s;
-  union u_sockaddr {
-    struct sockaddr sa;
-    struct sockaddr_in in;
-#ifdef AF_INET6
-    struct sockaddr_in6 in6;
-#endif
-#ifdef HAVE_LOCAL_SOCKETS
-    struct sockaddr_un un;
-#endif
-  } saddr;
+  union u_sockaddr saddr;
   socklen_t len = sizeof saddr;
   ptrdiff_t count;
 
@@ -7976,21 +7975,10 @@ restore_nofile_limit (void)
 }
 
 
-DEFUN ("get-external-sockname", Fget_external_sockname, Sget_external_sockname, 0, 0, 0,
-       doc: /* Return the path of an external socket passed to Emacs.
-Otherwise return nil.  */)
-     (void)
-{
-    if (external_sock_name)
-        return make_string(external_sock_name, strlen(external_sock_name));
-    else
-        return Qnil;
-}
-
 /* This is not called "init_process" because that is the name of a
    Mach system call, so it would cause problems on Darwin systems.  */
 void
-init_process_emacs (int sockfd, char *sockname)
+init_process_emacs (int sockfd)
 {
 #ifdef subprocesses
   int i;
@@ -8025,7 +8013,18 @@ init_process_emacs (int sockfd, char *sockname)
 #endif
 
   external_sock_fd = sockfd;
-  external_sock_name = sockname;
+  Lisp_Object sockname = Qnil;
+# if HAVE_GETSOCKNAME
+  if (0 <= sockfd)
+    {
+      union u_sockaddr sa;
+      socklen_t salen = sizeof sa;
+      if (getsockname (sockfd, &sa.sa, &salen) == 0)
+        sockname = conv_sockaddr_to_lisp (&sa.sa, salen);
+    }
+# endif
+  Vinternal__external_sockname = sockname;
+
   max_desc = -1;
   memset (fd_callback_info, 0, sizeof (fd_callback_info));
 
@@ -8218,6 +8217,10 @@ These functions are called in the order of the list, until one of them
 returns non-`nil'.  */);
   Vinterrupt_process_functions = list1 (Qinternal_default_interrupt_process);
 
+  DEFVAR_LISP ("internal--external-sockname", Vinternal__external_sockname,
+               doc: /* Name of external socket passed to Emacs, or nil if none.  */);
+  Vinternal__external_sockname = Qnil;
+
   DEFSYM (Qinternal_default_interrupt_process,
           "internal-default-interrupt-process");
   DEFSYM (Qinterrupt_process_functions, "interrupt-process-functions");
@@ -8320,5 +8323,4 @@ returns non-`nil'.  */);
   defsubr (&Sprocess_inherit_coding_system_flag);
   defsubr (&Slist_system_processes);
   defsubr (&Sprocess_attributes);
-  defsubr (&Sget_external_sockname);
 }