qpb: Add support for protobuf.

Infrastructure that allows protocol buffers to be used in Quagga. The
changes below comprise of:

  - Build hooks

  - Protobuf definitions for common types.

  - Library routines for working with protobuf, including functions
    that help translate between common quagga types and their protobuf
    equivalents.

Changes:

  * qpb/{Makefile.am,README.txt,qpb.h,.gitignore}

    Add the qpb library, which provides shared code and definitions
    for using protocol buffers in quagga code.

  * qpb/qpb.proto

    Protobuf definitions that can be shared by all of quagga.

  * qpb/linear_allocator.h

    An allocator that allocates memory by walking down towards the end
    of a buffer. This is used to cheaply allocate/deallocate memory on
    the stack for protobuf operations.

  * qpb/qpb_allocator.[ch]

    Thin layer that allows a linear allocator to be used with the
    protobuf-c library.

  * common.am

    This is an automake fragment that is intended to be shared by
    Makefile.am files in the tree. It currently includes definitions
    related to protobuf.

  * configure.ac

    - Add logic to optionally build protobuf code.

      By default, protobuf support is enabled if the protobuf C
      compiler (protoc-c) is available, and the associated header
      files/library can be found.

      The user can choose to override this behavior via the new
      --disable-protobuf/--enable-protobuf flags.

    - Include the quagga protobuf library (qpb) in the build.

  * .gitignore

    Ignore source code generated by protobuf compiler.

  * Makefile.am

    Add 'qpb' to the list of subdirectories.

Signed-off-by: Avneesh Sachdev <avneesh@sproute.com>

Edited: Paul Jakma <paul.jakma@hpe.com>: Change the sense of the
        configure enable option to require explicit specifying, as
        an experimental feature.

1 files changed, 121 insertions, 0 deletions

diff --git a/qpb/qpb.proto b/qpb/qpb.proto
new file mode 100644
index 000000000..7ee409df8
--- /dev/null
+++ b/qpb/qpb.proto
@@ -0,0 +1,121 @@
+/*
+ * qpb.proto
+ *
+ * @copyright Copyright (C) 2016 Sproute Networks, Inc.
+ *
+ * @author Avneesh Sachdev <avneesh@sproute.com>
+ *
+ * Permission is granted to use, copy, modify and/or distribute this
+ * software under either one of the licenses below.
+ *
+ * Note that if you use other files from the Quagga tree directly or
+ * indirectly, then the licenses in those files still apply.
+ *
+ * Please retain both licenses below when modifying this code in the
+ * Quagga tree.
+ */
+
+/*
+ * License Option 1: GPL
+ *
+ * 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 of the License, 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.,
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+/*
+ * License Option 2: ISC License
+ *
+ * Permission to use, copy, modify, and/or distribute this software
+ * for any purpose with or without fee is hereby granted, provided
+ * that the above copyright notice and this permission notice appear
+ * in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * Protobuf definitions pertaining to the Quagga Protobuf component.
+ */
+package qpb;
+
+enum AddressFamily {
+  UNKNOWN_AF = 0;
+  IPV4 = 1;		// IP version 4
+  IPV6 = 2;		// IP version 6
+};
+
+enum SubAddressFamily {
+  UNKNOWN_SAF = 0;
+  UNICAST = 1;
+  MULTICAST = 2;
+};
+
+//
+// An IP version 4 address, such as 10.1.1.1.
+//
+message Ipv4Address {
+  required fixed32 value = 1 ;
+};
+
+message Ipv6Address {
+
+  // 16 bytes.
+  required bytes bytes = 1;
+};
+
+//
+// An IP version 4 or IP version 6 address.
+//
+message L3Address {
+  optional Ipv4Address v4 = 1;
+  optional Ipv6Address v6 = 2;
+};
+
+//
+// An IP prefix, such as 10.1/16.
+// We use the message below to represent both IPv4 and IPv6 prefixes.
+message L3Prefix {
+  required uint32 length = 1;
+  required bytes bytes = 2;
+};
+
+//
+// Something that identifies an interface on a machine. It can either
+// be a name (for instance, 'eth0') or a number currently.
+//
+message IfIdentifier {
+  optional uint32 index = 1;
+  optional string name = 2;
+};
+
+enum Protocol {
+  UNKNOWN_PROTO = 0;
+  LOCAL = 1;
+  CONNECTED = 2;
+  KERNEL = 3;
+  STATIC = 4;
+  RIP = 5;
+  RIPNG = 6;
+  OSPF = 7;
+  ISIS = 8;
+  BGP = 9;
+  OTHER = 10;
+}
\ No newline at end of file