1 files changed, 180 insertions, 0 deletions
diff --git a/login/utmpd/connection.c b/login/utmpd/connection.c
new file mode 100644
index 0000000000..4e1663189d
--- /dev/null
+++ b/login/utmpd/connection.c
@@ -0,0 +1,180 @@
+/* Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
+
+   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 <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include "utmpd-private.h"
+
+
+/* Prototypes for the local functions.  */
+static client_connection *alloc_connection (void);
+static void free_connection (client_connection *connection);
+static int set_nonblock_flag (int desc, int value);
+
+
+/* The head of the connection list.  */
+static client_connection *connection_list = NULL;
+
+
+/* Accept connection on SOCK, with access permissions given by ACCESS.
+   Returns a pointer to a newly allocated client_connection if
+   successful, NULL if not.  */
+client_connection *
+accept_connection (int sock, int access)
+{
+  client_connection *connection;
+
+  connection = alloc_connection ();
+  if (connection == NULL)
+    return NULL;
+
+  connection->sock = accept (sock, NULL, NULL);
+  connection->access = access;
+  if (connection->sock < 0)
+    {
+      free_connection (connection);
+      return NULL;
+    }
+  
+  if (set_nonblock_flag (connection->sock, 1) < 0)
+    {
+      close_connection (connection);
+      return NULL;
+    }
+
+  return connection;  
+}
+
+
+/* Close CONNECTION.  */
+void
+close_connection (client_connection *connection)
+{
+  close (connection->sock);
+  free_connection (connection);
+}
+
+
+/* Return the connection for SOCK.  */
+client_connection *
+find_connection (int sock)
+{
+  client_connection *connection;
+
+  for (connection = connection_list; connection;
+       connection = connection->next)
+    {
+      if (connection->sock == sock)
+	return connection;
+    }
+
+  return NULL;
+}
+
+
+static client_connection *
+alloc_connection (void)
+{
+  client_connection *connection;
+  size_t read_bufsize = 1024;
+  size_t write_bufsize = 1024;
+
+  connection = (client_connection *)malloc (sizeof (client_connection));
+  if (connection == NULL)
+    return NULL;
+
+  memset (connection, 0, sizeof (client_connection));
+
+  /* Allocate read buffer.  */
+  connection->read_base = malloc (read_bufsize);
+  connection->read_ptr = connection->read_base;
+  connection->read_end = connection->read_base + read_bufsize;
+  if (connection->read_base == NULL)
+    {
+      free (connection);
+      return NULL;
+    }
+
+  /* Allocate write buffer.  */
+  connection->write_base = malloc (write_bufsize);
+  connection->write_ptr = connection->write_base;
+  connection->write_end = connection->write_base + write_bufsize;
+  if (connection->write_base == NULL)
+    {
+      free (connection->read_base);
+      free (connection);
+      return NULL;
+    }
+
+  /* Link connection.  */
+  connection->next = connection_list;
+  connection_list = connection;
+  if (connection->next)
+    connection->next->prev = connection;
+  
+  return connection;
+}
+
+
+static void
+free_connection (client_connection *connection)
+{
+  /* Unlink connection.  */
+  if (connection->next)
+    connection->next->prev = connection->prev;
+  if (connection->prev)
+    connection->prev->next = connection->next;
+
+  /* Take care of the head of the list.  */
+  if (connection == connection_list)
+    connection_list = connection->next;
+  
+  /* Free buffers.  */
+  if (connection->read_base)
+    free (connection->read_base);
+  if (connection->write_base)
+    free (connection->write_base);
+
+  free (connection);
+}
+
+
+/* Set the `O_NONBLOCK' flag of DESC if VALUE is nonzero,
+   or clear the flag if VALUE is 0.
+   Return 0 on success, or -1 on error with `errno' set. */
+static int
+set_nonblock_flag (int desc, int value)
+{
+  int oldflags = fcntl (desc, F_GETFL, 0);
+  /* If reading the flags failed, return error indication now. */
+  if (oldflags == -1)
+    return -1;
+  /* Set just the flag we want to set. */
+  if (value != 0)
+    oldflags |= O_NONBLOCK;
+  else
+    oldflags &= ~O_NONBLOCK;
+  /* Store modified flag word in the descriptor. */
+  return fcntl (desc, F_SETFL, oldflags);
+}