Merge pull request #1934 from libgit2/relicense-examples

Relicense examples under CC0

CONTRIBUTING.md

@@ -3,6 +3,12 @@
 We're making it easy to do interesting things with git, and we'd love to have
 your help.
 
+## Licensing
+
+By contributing to libgit2, you agree to release your contribution under the terms of the license.
+For code under `examples`, this is governed by the [CC0 Public Domain Dedication](examples/COPYING).
+All other code is released under the [GPL v2 with linking exception](COPYING).
+
 ## Discussion & Chat
 
 We hang out in the #libgit2 channel on irc.freenode.net.
@@ -70,7 +76,7 @@ you're porting code *from* to see what you need to do.  As a general rule,
 MIT and BSD (3-clause) licenses are typically no problem.  Apache 2.0
 license typically doesn't work due to GPL incompatibility.
 
-If you are pulling in code from core Git, another project or code you've pulled from 
+If you are pulling in code from core Git, another project or code you've pulled from
 a forum / Stack Overflow then please flag this in your PR and also make sure you've
 given proper credit to the original author in the code snippet.
 

README.md

@@ -7,9 +7,11 @@ libgit2 - the Git linkable library
 re-entrant linkable library with a solid API, allowing you to write native
 speed custom Git applications in any language with bindings.
 
-`libgit2` is licensed under a **very permissive license** (GPLv2 with a special Linking Exception).
+`libgit2` is licensed under a **very permissive license** (GPLv2 with a special
-This basically means that you can link it (unmodified) with any kind of software without having to
+Linking Exception).  This basically means that you can link it (unmodified)
-release its source code.
+with any kind of software without having to release its source code.
+Additionally, the example code has been released to the public domain (see the
+[separate license](examples/COPYING) for more information).
 
 * Website: [libgit2.github.com](http://libgit2.github.com)
 * StackOverflow Tag: [libgit2](http://stackoverflow.com/questions/tagged/libgit2)

examples/COPYING

@@ -0,0 +1,121 @@
+Creative Commons Legal Code
+
+CC0 1.0 Universal
+
+    CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT PROVIDE
+    LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT CREATE AN
+    ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES THIS
+    INFORMATION ON AN "AS-IS" BASIS. CREATIVE COMMONS MAKES NO WARRANTIES
+    REGARDING THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS
+    PROVIDED HEREUNDER, AND DISCLAIMS LIABILITY FOR DAMAGES RESULTING FROM
+    THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS PROVIDED
+    HEREUNDER.
+
+Statement of Purpose
+
+The laws of most jurisdictions throughout the world automatically confer
+exclusive Copyright and Related Rights (defined below) upon the creator
+and subsequent owner(s) (each and all, an "owner") of an original work of
+authorship and/or a database (each, a "Work").
+
+Certain owners wish to permanently relinquish those rights to a Work for
+the purpose of contributing to a commons of creative, cultural and
+scientific works ("Commons") that the public can reliably and without fear
+of later claims of infringement build upon, modify, incorporate in other
+works, reuse and redistribute as freely as possible in any form whatsoever
+and for any purposes, including without limitation commercial purposes.
+These owners may contribute to the Commons to promote the ideal of a free
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+
+For these and/or other purposes and motivations, and without any
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+
+1. Copyright and Related Rights. A Work made available under CC0 may be
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+     directive); and
+vii. other similar, equivalent or corresponding rights throughout the
+     world based on applicable law or treaty, and any national
+     implementations thereof.
+
+2. Waiver. To the greatest extent permitted by, but not in contravention
+of, applicable law, Affirmer hereby overtly, fully, permanently,
+irrevocably and unconditionally waives, abandons, and surrenders all of
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+as contemplated by Affirmer's express Statement of Purpose.
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+be judged legally invalid or ineffective under applicable law, then the
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+"License"). The License shall be deemed effective as of the date CC0 was
+applied by Affirmer to the Work. Should any part of the License for any
+reason be judged legally invalid or ineffective under applicable law, such
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+of the License, and in such case Affirmer hereby affirms that he or she
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+Rights in the Work or (ii) assert any associated claims and causes of
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+    Work.
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+    party to this document and has no duty or obligation with respect to
+    this CC0 or use of the Work.

examples/README.md

@@ -8,7 +8,10 @@ handling, and cross-platform compatibility in the same manner as the rest
 of the code in libgit2, so copy with caution.
 
 That being said, you are welcome to copy code from these examples as
-desired when using libgit2.
+desired when using libgit2. They have been [released to the public domain][cc0],
+so there are no restrictions on their use.
+
+[cc0]: COPYING
 
 For annotated HTML versions, see the "Examples" section of:
 

examples/add.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "add" example - shows how to modify the index
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/cat-file.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "cat-file" example - shows how to print data from the ODB
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/common.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * Utilities library for libgit2 examples
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/common.h

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * Utilities library for libgit2 examples
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include <stdio.h>

examples/diff.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "diff" example - shows how to use the diff API
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/general.c

@@ -1,3 +1,17 @@
+/*
+ * libgit2 "general" example - shows basic libgit2 concepts
+ *
+ * Written by the libgit2 contributors
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+
 // [**libgit2**][lg] is a portable, pure C implementation of the Git core
 // methods provided as a re-entrant linkable library with a solid API,
 // allowing you to write native speed custom Git applications in any

examples/init.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "init" example - shows how to initialize a new repo
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/log.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "log" example - shows how to walk history and get commit info
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/rev-list.c

@@ -1,8 +1,16 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "rev-list" example - shows how to transform a rev-spec into a list
+ * of commit ids
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/rev-parse.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "rev-parse" example - shows how to parse revspecs
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/showindex.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "showindex" example - shows how to extract data from the index
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"

examples/status.c

@@ -1,8 +1,15 @@
 /*
- * Copyright (C) the libgit2 contributors. All rights reserved.
+ * libgit2 "status" example - shows how to use the status APIs
  *
- * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * Written by the libgit2 contributors
- * a Linking Exception. For full terms see the included COPYING file.
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #include "common.h"