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-rw-r--r--inet/getipnodebyad.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/inet/getipnodebyad.c b/inet/getipnodebyad.c
new file mode 100644
index 0000000000..d9d5ba8887
--- /dev/null
+++ b/inet/getipnodebyad.c
@@ -0,0 +1,59 @@
+/* Copyright (C) 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <netdb.h>
+#include <stdlib.h>
+
+#include "nsswitch.h"
+
+/* We avoid using a too large buffer in case the user is accumulating the
+   results and there is lots of unused space in the allocated buffer.  */
+#define BUFLEN	512
+
+
+struct hostent *
+getipnodebyaddr (const char *addr, size_t len, int type, int *error_num)
+{
+  size_t buffer_size;
+  char *buffer;
+  struct hostent *result;
+
+  buffer_size = BUFLEN;
+  buffer = malloc (buffer_size);
+
+  while (buffer != NULL
+	 && __gethostbyaddr_r (addr, len, type, (struct hostent *) buffer,
+			       (char *) ((struct hostent *) buffer + 1),
+			       buffer_size - sizeof (struct hostent),
+			       &result, error_num) == ERANGE
+	 && *error_num == NETDB_INTERNAL)
+    {
+      buffer_size += BUFLEN;
+      buffer = realloc (buffer, buffer_size);
+      if (buffer == NULL)
+	{
+	  *error_num = TRY_AGAIN;
+	  assert (result == NULL);
+	  return NULL;
+	}
+    }
+
+  return buffer == NULL ? NULL : result;
+}