Convert license header to "proper" Apache 2 license header. (#767)

It comes from here, which the NVIDIA legal team recommends:

https://gist.github.com/Rypac/7349957f95f0713143fda2f3d3bc10c8

Basically, the NVIDIA legal team requires that my code contributions
have an Apache 2 license header. If I were to contribute to an
existing file (which I want to do), I would have to manually change
each file's header for legal compliance. @danpovey said that going
ahead and changing all the file headers to an official Apache 2 header
sounded reasonable.

I used codemod (`pip install codemod`) for this, with the following
script:

```
read -r -d '' replacement << EOM
   Copyright     \1 See LICENSE for clarification regarding multiple authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
EOM

codemod --exclude-paths build -m -d . --extensions cu,h \
        "Copyright \(c\) (.+) See LICENSE for clarification regarding multiple authors" \
        "$replacement"

read -r -d '' replacement << EOM
   Copyright     \1 authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
EOM

codemod --exclude-paths build -m -d . --extensions cmake,py \
        "Copyright \(c\) (.+) authors" \
        "$replacement"

codemod --exclude-paths build -m -d .github --extensions yml \
        "Copyright \(c\) (.+) authors" \
        "$replacement"

read -r -d '' replacement << EOM
   Copyright     \1
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
EOM

codemod --exclude-paths build -d scripts --extensions sh \
        "Copyright \(c\) (.+)" \
        "$replacement"
```

Codemod, unlike sed, is interactive. I manually checked that every
replacement made sense. Note that I applied this only to .cu, .h,
.cmake, and .py files.

Co-authored-by: Daniel Galvez <[email protected]>

.github/workflows/build-cpu.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/build.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2020  Fangjun Kuang ([email protected])
+# Copyright      2020  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/build_conda.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Xiaomi Corp.       (author: Fangjun Kuang)
+# Copyright      2021  Xiaomi Corp.       (author: Fangjun Kuang)
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/build_conda_cpu.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Xiaomi Corp.       (author: Fangjun Kuang)
+# Copyright      2021  Xiaomi Corp.       (author: Fangjun Kuang)
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/nightly-cpu.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 name: nightly-cpu
 

.github/workflows/nightly-windows.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 name: nightly-windows
 

.github/workflows/run-tests-cpu.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/run-tests.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2020  Fangjun Kuang ([email protected])
+# Copyright      2020  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # refer to https://github.com/actions/starter-workflows/pull/47/files
 

.github/workflows/style_check.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2020  Fangjun Kuang ([email protected])
+# Copyright      2020  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 name: style_check
 

.github/workflows/windows-conda.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 
 name: build-windows-conda

.github/workflows/windows.yml

@@ -1,6 +1,18 @@
-# Copyright (c)  2021  Fangjun Kuang ([email protected])
+# Copyright      2021  Fangjun Kuang ([email protected])
 
 # See ../../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 
 name: build-windows

cmake/cub.cmake

@@ -1,5 +1,17 @@
-# Copyright (c) 2020 Fangjun Kuang ([email protected])
+# Copyright     2020 Fangjun Kuang ([email protected])
 # See ../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 function(download_cub)
   if(CMAKE_VERSION VERSION_LESS 3.11)

cmake/googletest.cmake

@@ -1,5 +1,17 @@
-# Copyright (c) 2020 Fangjun Kuang ([email protected])
+# Copyright     2020 Fangjun Kuang ([email protected])
 # See ../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 function(download_googltest)
   if(CMAKE_VERSION VERSION_LESS 3.11)

cmake/moderngpu.cmake

@@ -1,5 +1,17 @@
-# Copyright (c)  2020  Mobvoi AI Lab, Beijing, China (authors: Fangjun Kuang)
+# Copyright      2020  Mobvoi AI Lab, Beijing, China (authors: Fangjun Kuang)
 # See ../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 function(download_moderngpu)
   if(CMAKE_VERSION VERSION_LESS 3.11)

cmake/pybind11.cmake

@@ -1,5 +1,17 @@
-# Copyright (c) 2020 Fangjun Kuang ([email protected])
+# Copyright     2020 Fangjun Kuang ([email protected])
 # See ../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 function(download_pybind11)
   if(CMAKE_VERSION VERSION_LESS 3.11)

cmake/transform.cmake

@@ -1,5 +1,17 @@
-# Copyright (c) 2021 Fangjun Kuang ([email protected])
+# Copyright     2021 Fangjun Kuang ([email protected])
 # See ../LICENSE for clarification regarding multiple authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 # This function is used to copy foo.cu to foo.cc
 # Usage:

k2/csrc/algorithms.cu

@@ -1,7 +1,19 @@
 /**
- * Copyright (c)  2020  Xiaomi Corporation (authors: Haowen Qiu)
+ * Copyright      2020  Xiaomi Corporation (authors: Haowen Qiu)
  *
  * See LICENSE for clarification regarding multiple authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #include <algorithm>

k2/csrc/algorithms.h

@@ -1,7 +1,19 @@
 /**
- * Copyright (c)  2020  Xiaomi Corporation (authors: Daniel Povey, Haowen Qiu)
+ * Copyright      2020  Xiaomi Corporation (authors: Daniel Povey, Haowen Qiu)
  *
  * See LICENSE for clarification regarding multiple authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #ifndef K2_CSRC_ALGORITHMS_H_

k2/csrc/algorithms_test.cu

@@ -1,7 +1,19 @@
 /**
- * Copyright (c)  2020  Xiaomi Corporation (authors: Haowen Qiu)
+ * Copyright      2020  Xiaomi Corporation (authors: Haowen Qiu)
  *
  * See LICENSE for clarification regarding multiple authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #include <gmock/gmock.h>

k2/csrc/array.h

@@ -1,8 +1,20 @@
 /**
- * Copyright (c)  2020  Xiaomi Corporation (authors: Daniel Povey, Haowen Qiu)
+ * Copyright      2020  Xiaomi Corporation (authors: Daniel Povey, Haowen Qiu)
  *                      Mobvoi Inc.        (authors: Fangjun Kuang)
  *
  * See LICENSE for clarification regarding multiple authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  */
 
 #ifndef K2_CSRC_ARRAY_H_