Prefer stpcpy to strcat

* admin/merge-gnulib (GNULIB_MODULES): Add stpcpy.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/stpcpy.c, m4/stpcpy.m4: New files, from gnulib.
* lib-src/ebrowse.c (sym_scope_1, operator_name, open_file):
* lib-src/emacsclient.c (get_server_config, set_local_socket)
(start_daemon_and_retry_set_socket):
* lib-src/etags.c (main, C_entries, relative_filename):
* lib-src/pop.c (sendline):
* lib-src/update-game-score.c (main):
* lwlib/xlwmenu.c (resource_widget_value):
* src/callproc.c (child_setup):
* src/dbusbind.c (xd_signature_cat):
* src/doc.c (get_doc_string, Fsnarf_documentation):
* src/editfns.c (Fuser_full_name):
* src/frame.c (xrdb_get_resource):
* src/gtkutil.c (xg_get_file_with_chooser):
* src/tparam.c (tparam1):
* src/xfns.c (xic_create_fontsetname):
* src/xrdb.c (gethomedir, get_user_db, get_environ_db):
* src/xsmfns.c (smc_save_yourself_CB):
Rewrite to avoid the need for strcat, typically by using stpcpy
and/or lispstpcpy.  strcat tends to be part of O(N**2) algorithms.
* src/doc.c (sibling_etc):
* src/xrdb.c (xdefaults):
Now a top-level static constant.

1 files changed, 16 insertions, 13 deletions

diff --git a/lib-src/ebrowse.c b/lib-src/ebrowse.c
index 29a88e85f02..b7431593c3e 100644
--- a/lib-src/ebrowse.c
+++ b/lib-src/ebrowse.c
@@ -1150,19 +1150,19 @@ sym_scope_1 (struct sym *p)
   if (*scope_buffer)
     {
       ensure_scope_buffer_room (3);
-      strcat (scope_buffer, "::");
+      strcpy (scope_buffer + scope_buffer_len, "::");
       scope_buffer_len += 2;
     }
 
   len = strlen (p->name);
   ensure_scope_buffer_room (len + 1);
-  strcat (scope_buffer, p->name);
+  strcpy (scope_buffer + scope_buffer_len, p->name);
   scope_buffer_len += len;
 
   if (HAS_FLAG (p->flags, F_TEMPLATE))
     {
       ensure_scope_buffer_room (3);
-      strcat (scope_buffer, "<>");
+      strcpy (scope_buffer + scope_buffer_len, "<>");
       scope_buffer_len += 2;
     }
 
@@ -2797,24 +2797,25 @@ operator_name (int *sc)
       s = token_string (LA1);
       MATCH ();
 
-      len = strlen (s) + 10;
+      ptrdiff_t slen = strlen (s);
+      len = slen + 10;
       if (len > id_size)
 	{
 	  size_t new_size = max (len, 2 * id_size);
 	  id = (char *) xrealloc (id, new_size);
 	  id_size = new_size;
 	}
-      strcpy (id, s);
+      char *z = stpcpy (id, s);
 
       /* Vector new or delete?  */
       if (LOOKING_AT ('['))
 	{
-	  strcat (id, "[");
+	  z = stpcpy (z, "[");
 	  MATCH ();
 
 	  if (LOOKING_AT (']'))
 	    {
-	      strcat (id, "]");
+	      strcpy (z, "]");
 	      MATCH ();
 	    }
 	}
@@ -2830,7 +2831,7 @@ operator_name (int *sc)
 	  id = (char *) xrealloc (id, new_size);
 	  id_size = new_size;
 	}
-      strcpy (id, "operator");
+      char *z = stpcpy (id, "operator");
 
       /* Beware access declarations of the form "X::f;" Beware of
 	 `operator () ()'.  Yet another difficulty is found in
@@ -2842,14 +2843,16 @@ operator_name (int *sc)
 	  len += strlen (s) + 2;
 	  if (len > id_size)
 	    {
+	      ptrdiff_t idlen = z - id;
 	      size_t new_size = max (len, 2 * id_size);
 	      id = (char *) xrealloc (id, new_size);
 	      id_size = new_size;
+	      z = id + idlen;
 	    }
 
 	  if (*s != ')' && *s != ']')
-	    strcat (id, " ");
-          strcat (id, s);
+	    *z++ = ' ';
+          z = stpcpy (z, s);
           MATCH ();
 
 	  /* If this is a simple operator like `+', stop now.  */
@@ -3462,9 +3465,9 @@ open_file (char *file)
 	  buffer = (char *) xrealloc (buffer, buffer_size);
 	}
 
-      strcpy (buffer, path->path);
-      strcat (buffer, "/");
-      strcat (buffer, file);
+      char *z = stpcpy (buffer, path->path);
+      *z++ = '/';
+      strcpy (z, file);
       fp = fopen (buffer, "r");
     }