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-rw-r--r--.gitignore3
-rw-r--r--COPYING165
-rw-r--r--README24
-rwxr-xr-xrebarbin0 -> 119212 bytes
-rw-r--r--rebar.config3
-rw-r--r--src/guid.app.src9
-rw-r--r--src/guid.erl55
-rw-r--r--test/guid_test.erl29
8 files changed, 288 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.eunit/
+ebin/
+*~
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..65c5ca8
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,165 @@
+ GNU LESSER GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+ This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+ 0. Additional Definitions.
+
+ As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+ "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+ An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
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+Application with the Library. The particular version of the Library
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+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+ 1. Exception to Section 3 of the GNU GPL.
+
+ You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+ 2. Conveying Modified Versions.
+
+ If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
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+ b) under the GNU GPL, with none of the additional permissions of
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+ 3. Object Code Incorporating Material from Library Header Files.
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+ If the Library as you received it specifies that a proxy can decide
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diff --git a/README b/README
new file mode 100644
index 0000000..1dbe3f6
--- /dev/null
+++ b/README
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+Some function to generate v4 uuids
+==================================
+
+Generate a random uuid:
+
+ 1> UUID = guid:v4().
+ <<254,194,254,188,1,12,79,173,84,118,109,153,143,115,228,127>>
+
+Convert to text representation:
+
+ 2> guid:unparse(UUID).
+ "0ee31c01-26cc-43f1-a0f9-b52c6de7fcf7"
+
+Check it's version:
+
+ 3> guid:version(UUID).
+ 4
+
+Generate text representation drectly:
+
+ 4> guid:v4string().
+ "68718f41-06ff-49a8-8283-00582b2d5269"
+
+
diff --git a/rebar b/rebar
new file mode 100755
index 0000000..7bdb274
--- /dev/null
+++ b/rebar
Binary files differ
diff --git a/rebar.config b/rebar.config
new file mode 100644
index 0000000..21412f8
--- /dev/null
+++ b/rebar.config
@@ -0,0 +1,3 @@
+%%-*- mode: erlang -*-
+
+{deps, []}.
diff --git a/src/guid.app.src b/src/guid.app.src
new file mode 100644
index 0000000..afb6108
--- /dev/null
+++ b/src/guid.app.src
@@ -0,0 +1,9 @@
+%%-*- mode: erlang -*-
+{application, guid,
+ [
+ {description, "Simple v4 uuid generator"},
+ {vsn, git},
+ {registered, []},
+ {applications, []},
+ {env, []}
+ ]}.
diff --git a/src/guid.erl b/src/guid.erl
new file mode 100644
index 0000000..4c3fc15
--- /dev/null
+++ b/src/guid.erl
@@ -0,0 +1,55 @@
+%% @author Guido G√ľnther <agx@sigxcpu.org>
+%% @copyright 2013 godiug.net
+%%
+%% This library is free software; you can redistribute it and/or
+%% modify it under the terms of the GNU Lesser General Public
+%% License as published by the Free Software Foundation; either
+%% version 3 of the License, or (at your option) any later version.
+%%
+%% This 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
+%% Lesser General Public License for more details.
+%%
+%% You should have received a copy of the GNU Lesser General Public
+%% License along with this library. If not, see
+%% <http://www.gnu.org/licenses/>.
+%%
+%% @doc Simple v4 uuid generator
+
+-module(guid).
+-export([v4/0,
+ v4string/0,
+ unparse/1,
+ version/1]).
+
+%% @doc generate a version 4 uuid as bin
+v4() ->
+ << D1:32, D2:16, D3:16, D4:64 >> = crypto:rand_bytes(16),
+ << D1:32, D2:16, 4:4, D3:12, D4:64 >>.
+
+%% @doc generate a version 4 uuid as string
+v4string() ->
+ unparse(v4()).
+
+%% @doc convert a uuid from bin to string
+unparse(UUID) ->
+ lists:flatten(
+ io_lib:format("~8.16.0b-"
+ "~4.16.0b-"
+ "~4.16.0b-"
+ "~2.16.0b~2.16.0b-"
+ "~12.16.0b", parts(UUID))).
+
+%% @doc get a uuid's version number
+version(<< _:48, Version:4, _:76 >>) ->
+ Version.
+
+%% @private
+% Return the parts of the uuid as per rfc4122:
+% time_low (32), time_mid (16), time_hi_and_version (16)
+% clock_seq_hi_and_reseved (8), clock_seq_low(8), node (48)
+parts(<< TL:32, TM:16, THV:16, CSHR:8, CSL:8, N:48 >>) ->
+ [TL, TM, THV, CSHR, CSL, N].
+
+
diff --git a/test/guid_test.erl b/test/guid_test.erl
new file mode 100644
index 0000000..d98c853
--- /dev/null
+++ b/test/guid_test.erl
@@ -0,0 +1,29 @@
+-module(guid_test).
+-include_lib("eunit/include/eunit.hrl").
+
+% Test descriptions
+v4_test_() ->
+ [{"A v4 uuid must have version 4",
+ check_v4_version()},
+ {"A uuid must be 16 bytes",
+ check_v4_length()}
+ ].
+
+text_test_() ->
+ [{"The text representation must be 38 characters long",
+ check_v4_string_length()}
+ ].
+
+% Tests
+check_v4_version() ->
+ Uuid = guid:v4(),
+ [?_assertEqual(guid:version(Uuid), 4)].
+
+
+check_v4_length() ->
+ Uuid = guid:v4(),
+ [?_assertEqual(byte_size(Uuid), 16)].
+
+check_v4_string_length() ->
+ String = guid:v4string(),
+ [?_assertEqual(length(String), 36)].