https://github.com/msantos/erpcgen
RPC/XDR protocol compiler (from jungerl)
https://github.com/msantos/erpcgen
Last synced: about 1 month ago
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RPC/XDR protocol compiler (from jungerl)
- Host: GitHub
- URL: https://github.com/msantos/erpcgen
- Owner: msantos
- License: other
- Created: 2012-09-03T21:02:57.000Z (almost 13 years ago)
- Default Branch: master
- Last Pushed: 2019-10-04T14:08:38.000Z (over 5 years ago)
- Last Synced: 2025-04-27T12:37:02.664Z (about 1 month ago)
- Language: Erlang
- Size: 105 KB
- Stars: 14
- Watchers: 3
- Forks: 10
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG
- License: LICENSE
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README
erpcgen
=======
Erlang [external data representation](https://en.wikipedia.org/wiki/External_Data_Representation) ([XDR](https://tools.ietf.org/html/rfc4506)) protocol compiler
Build
-----
$ rebar3 compile
Examples
--------
~~~ example.x
struct example_int {
int n;
};
struct example_nested {
example_int n;
int x;
};
enum example_enum {
one = 1,
two = 2,
three = 3
};
~~~
To convert the XDR file:
~~~ erlang
% NOTE: the filename is an atom without the ".x" extension
erpcgen:file('example', [xdrlib]).
~~~
The result:
~~~ erlang
%%
%% example_xdr was generated by erpcgen (do not edit)
%% date: Nov 9 10:28:28 2017
%%
-module(example_xdr).
-export([enc_example_int/1, dec_example_int/2]).
-export([enc_example_nested/1, dec_example_nested/2]).
-export([enc_example_enum/1, dec_example_enum/2]).
enc_example_int(_1) ->
case _1 of
{_2} ->
[<<_2:32>>]
end.
dec_example_int(_1, _2) ->
begin
begin
<<_:_2/binary,_3:32/signed,_/binary>> = _1,
_4 = _2 + 4
end,
{{_3},_4}
end.
enc_example_nested(_1) ->
case _1 of
{_3,_2} ->
[enc_example_int(_3),<<_2:32>>]
end.
dec_example_nested(_1, _2) ->
begin
{_3,_4} = dec_example_int(_1, _2),
begin
<<_:_4/binary,_5:32/signed,_/binary>> = _1,
_6 = _4 + 4
end,
{{_3,_5},_6}
end.
enc_example_enum(_1) ->
case _1 of
one ->
<<1:32>>;
two ->
<<2:32>>;
three ->
<<3:32>>
end.
dec_example_enum(_1, _2) ->
begin
<<_:_2/binary,_3:32,_/binary>> = _1,
case _3 of
1 ->
{one,_2 + 4};
2 ->
{two,_2 + 4};
3 ->
{three,_2 + 4}
end
end.
dec_example_enum_i2a(_4) ->
case _4 of
1 ->
one;
2 ->
two;
3 ->
three
end.
~~~
A longer example used for decoding the [libvirtd remote protocol](https://github.com/msantos/verx/blob/master/bin/mk_remote_protocol.escript).
History
-------
This version of erpcgen is a fork from [jungerl](https://github.com/gebi/jungerl/tree/master/lib/rpc) for use with [verx](https://github.com/msantos/verx).
The history of _erpcgen_ was discussed in [this thread](http://erlang.org/pipermail/erlang-questions/2012-December/071012.html). [Tony Rogvall](http://erlang.org/pipermail/erlang-questions/2012-December/071013.html) is the original author:
This code was initially written by me (Tony Rogvall). With improvements
by Martin Björklund, Luke Gorrie wrote the NFS examples. Later the
code was "stolen" by Sendmail.
Handling char/short
-------------------
If the XDR file contains `char` or `short` integers, conversion will
fail. These units can be replaced by `int`: the XDR wire protocol uses
a minimum size of 4 bytes.