Add/update copyright notice on all C++ files

This adds a copyright notice to all C++ files and the README clarifying
the license. (There is no change of the license.) This also removes a
few names explicitly mentioned as copyright holders, instead refering to
the git log which has a full list of all osm2pgsql developers. (There is
also still the AUTHORS file which names the most important developers.)

The only exception is the sprompt.cpp file which was taken from
PostgreSQL and keeps its original license information (and, of course,
the files in contrib).

Author: joto

README.md

@@ -187,6 +187,18 @@ Lua 5.1.4 (LuaJIT 2.1.0-beta3)
 If you have problems with osm2pgsql or want to report a bug, go to
 https://osm2pgsql.org/support/ .
 
+## License
+
+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.
+
 ## Contributing
 
 We welcome contributions to osm2pgsql. See [CONTRIBUTING.md](CONTRIBUTING.md)

src/db-check.cpp

@@ -1,3 +1,12 @@
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include "db-check.hpp"
 #include "logging.hpp"
 #include "pgsql.hpp"

src/db-check.hpp

@@ -1,6 +1,15 @@
 #ifndef OSM2PGSQL_DB_CHECK_HPP
 #define OSM2PGSQL_DB_CHECK_HPP
 
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include "options.hpp"
 
 /**

src/db-copy-mgr.hpp

@@ -1,6 +1,15 @@
 #ifndef OSM2PGSQL_DB_COPY_MGR_HPP
 #define OSM2PGSQL_DB_COPY_MGR_HPP
 
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include <cassert>
 #include <memory>
 #include <string>

src/db-copy.cpp

@@ -1,3 +1,12 @@
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include <cassert>
 
 #include "db-copy.hpp"

src/db-copy.hpp

@@ -1,6 +1,15 @@
 #ifndef OSM2PGSQL_DB_COPY_HPP
 #define OSM2PGSQL_DB_COPY_HPP
 
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include <condition_variable>
 #include <deque>
 #include <future>

src/dependency-manager.cpp

@@ -1,3 +1,11 @@
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
 
 #include "dependency-manager.hpp"
 #include "middle.hpp"

src/dependency-manager.hpp

@@ -1,6 +1,15 @@
 #ifndef OSM2PGSQL_DEPENDENCY_MANAGER_HPP
 #define OSM2PGSQL_DEPENDENCY_MANAGER_HPP
 
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include "osmtypes.hpp"
 
 #include <osmium/index/id_set.hpp>

src/domain-matcher.hpp

@@ -1,6 +1,15 @@
 #ifndef OSM2PGSQL_DOMAIN_MATCHER_HPP
 #define OSM2PGSQL_DOMAIN_MATCHER_HPP
 
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 #include <osmium/osm/tag.hpp>
 
 #include <cstring>

src/expire-tiles.cpp

@@ -1,8 +1,15 @@
+/**
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This file is part of osm2pgsql (https://osm2pgsql.org/).
+ *
+ * Copyright (C) 2006-2020 by the osm2pgsql developer community.
+ * For a full list of authors see the git log.
+ */
+
 /*
  * Dirty tile list generation
  *
- * Steve Hill <[email protected]>
- *
  * Please refer to the OpenPisteMap expire_tiles.py script for a demonstration
  * of how to make use of the output:
  * http://subversion.nexusuk.org/projects/openpistemap/trunk/scripts/expire_tiles.py