Initial revision

2 files changed, 123 insertions, 0 deletions

diff --git a/libshouldbeinlibc/localhost.c b/libshouldbeinlibc/localhost.c
new file mode 100644
index 00000000..f0c67541
--- /dev/null
+++ b/libshouldbeinlibc/localhost.c
@@ -0,0 +1,66 @@
+/* A slightly more convenient wrapper for gethostname
+
+   Copyright (C) 1996 Free Software Foundation, Inc.
+
+   Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include <unistd.h>
+#include <malloc.h>
+#include <string.h>
+#include <errno.h>
+
+/* Return the name of the localhost.  This is just a wrapper for gethostname,
+   which takes care of allocating a big enough buffer, and caches the result
+   after the first call (so the result should be copied before modification).
+   If something goes wrong, 0 is returned, and errno set.  */
+char *
+localhost ()
+{
+  static char *buf = 0;
+  static size_t buf_len = 0;
+
+  if (! buf)
+    {
+      do {
+	errno = 0;
+
+	if (buf) {
+	  buf_len += buf_len;
+	  buf = realloc (buf, buf_len);
+	} else {
+	  buf_len = 128;	/* Initial guess */
+	  buf = malloc (buf_len);
+	}
+
+	if (! buf)
+	  {
+	    errno = ENOMEM;
+	    return 0;
+	  }
+      } while ((gethostname(buf, buf_len) == 0 && !memchr (buf, '\0', buf_len))
+	       || errno == ENAMETOOLONG);
+
+      if (errno)
+	/* gethostname failed, abort.  */
+	{
+	  free (buf);
+	  buf = 0;
+	}
+    }
+
+  return buf;
+}
diff --git a/libshouldbeinlibc/shared-dom.c b/libshouldbeinlibc/shared-dom.c
new file mode 100644
index 00000000..0f8efdf8
--- /dev/null
+++ b/libshouldbeinlibc/shared-dom.c
@@ -0,0 +1,57 @@
+/* Deduce the shared portion of two hostnames
+
+   Copyright (C) 1996 Free Software Foundation, Inc.
+
+   Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include <unistd.h>
+#include <malloc.h>
+#include <string.h>
+#include <errno.h>
+
+/* Returns a pointer into HOST1 that is the part of the domain shared with
+   HOST2.  If the two do not share anything, the return value will point to
+   the end of HOST1.  If either host is NULL, NULL is returned.  */
+char *
+shared_domain (char *host1, char *host2)
+{
+  char *shared, *e1, *e2;
+
+  if (!host1 || !host2)
+    return 0;
+
+  /* Now compare HOST1 and HOST2 from the end.  */
+  e2 = host2 + strlen (host2);
+  e1 = host1 + strlen (host1);
+  shared = e1;
+
+  /* Ignore `absolute' syntax.  */
+  if (*e1 == '.')
+    e1--;
+  if (*e2 == '.')
+    e2--;
+
+  while (e1 > host1 && e2 > host2 && *e2 == *e1)
+    {
+      if (*e1 == '.')
+	shared = e1;		/* A common domain level has been passed. */
+      e1--;
+      e2--;
+    }
+
+  return shared;
+}