Add license check and formatting check (#156)

Add docs/Contributing.md
Add .editorconfig
Apply clang formatting to existing files

Signed-off-by: Alan Jowett <alanjo@microsoft.com>

Signed-off-by: Alan Jowett <alanjo@microsoft.com>

.clang-format

@@ -0,0 +1,23 @@
+BasedOnStyle: LLVM
+IndentWidth: 4
+ColumnLimit: 120
+AlignEscapedNewlines: Left
+AlignAfterOpenBracket: AlwaysBreak
+#
+# Bind * to the type rather than the name.
+PointerAlignment: Left
+#
+# Put function name on separate line from return type.
+AlwaysBreakAfterReturnType: All
+#
+# Put arguments either all on same line or on separate lines.
+BinPackArguments: false
+#
+# Put function parameters on separate lines.
+BinPackParameters: false
+#
+# Open brace goes on new line only when starting a new struct, enum, or func.
+BreakBeforeBraces: Mozilla
+#
+# Don't sort includes in alphabetical order because Windows headers are odd.
+SortIncludes: false

.editorconfig

@@ -0,0 +1,12 @@
+# Copyright (c) 2022-present, IO Visor Project
+# SPDX-License-Identifier: Apache-2.0
+
+# top-most EditorConfig file
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true

.gitignore

@@ -114,4 +114,5 @@ dmypy.json
 # Pyre type checker
 .pyre/
 
-.vscode/
+.vscode/
+.vs/

CMakeLists.txt

@@ -1,5 +1,6 @@
-#
 # Copyright (c) 2022-present, IO Visor Project
+# SPDX-License-Identifier: Apache-2.0
+#
 # All rights reserved.
 #
 # This source code is licensed in accordance with the terms specified in
@@ -9,6 +10,12 @@
 project("ubpf")
 cmake_minimum_required(VERSION 3.16)
 
+if (UBPF_INSTALL_GIT_HOOKS)
+  # Install Git pre-commit hook
+  file(COPY scripts/pre-commit scripts/commit-msg
+       DESTINATION "${PROJECT_SOURCE_DIR}/.git/hooks")
+endif()
+
 include("cmake/platform.cmake")
 include("cmake/settings.cmake")
 include("cmake/options.cmake")

aarch64_test/run-interpret.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 # Copyright (c) Microsoft Corporation
-# SPDX-License-Identifier: MIT
+# SPDX-License-Identifier: Apache-2.0
 
 # Work around for argument passing.
 qemu-aarch64 -L /usr/aarch64-linux-gnu build/bin/ubpf_plugin "$*" --interpret

aarch64_test/run-jit.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 # Copyright (c) Microsoft Corporation
-# SPDX-License-Identifier: MIT
+# SPDX-License-Identifier: Apache-2.0
 
 # Work around for argument passing.
 qemu-aarch64 -L /usr/aarch64-linux-gnu build/bin/ubpf_plugin "$*" --jit

cmake/options.cmake

@@ -1,5 +1,5 @@
-#
 # Copyright (c) 2022-present, IO Visor Project
+# SPDX-License-Identifier: Apache-2.0
 # All rights reserved.
 #
 # This source code is licensed in accordance with the terms specified in
@@ -15,6 +15,7 @@ option(UBPF_ENABLE_INSTALL "Set to true to enable the install targets")
 option(UBPF_ENABLE_TESTS "Set to true to enable tests")
 option(UBPF_ENABLE_PACKAGE "Set to true to enable packaging")
 option(UBPF_SKIP_EXTERNAL "Set to true to skip external projects")
+option(UBPF_INSTALL_GIT_HOOKS "Set to true to install git hooks" ON)
 
 # Note that the compile_commands.json file is only exporter when
 # using the Ninja or Makefile generator

docs/Contributing.md

@@ -0,0 +1,127 @@
+Development Guide
+=================
+
+Coding Conventions
+------------------
+
+* **DO** use fixed length types defined in `stdint.h` instead
+  of language keywords determined by the compiler (e.g., `int64_t, uint8_t`, not
+  `long, unsigned char`).
+
+* **DO** use `const` and `static` and visibility modifiers to scope exposure of
+   variables and methods as much as possible.
+
+* **DO** use doxygen comments, with \[in,out\]
+  [direction annotation](http://www.doxygen.nl/manual/commands.html#cmdparam) in all public API
+  headers. This is also encouraged, but not strictly required, for internal API
+  headers as well.
+
+* **DON'T** use global variables where possible.
+
+* **DON'T** use abbreviations unless they are already well-known terms known by
+  users (e.g., "app", "info"), or are already required for use by developers (e.g.,
+  "min", "max", "args").  Examples of bad use would be `num_widgets` instead of
+  `widget_count`, and `opt_widgets` instead of `option_widgets` or `optional_widgets`.
+
+* **DON'T** use hard-coded magic numbers for things that have to be consistent
+  between different files.  Instead use a `#define` or an enum or const value, as appropriate.
+
+* **DON'T** use the same C function name with two different prototypes across
+  the project where possible.
+
+* **DON'T** use commented-out code, or code in an `#if 0` or equivalent.  Make sure all code is actually
+  built.
+
+Header Files
+------------
+
+* **DO** make sure any header file can be included directly, without requiring other
+  headers to be included first.  That is, any dependencies should be included within
+  the header file itself.
+
+* **DO** include system headers (with `<>`) before local headers (with `""`), and list them
+  in alphabetical order where possible.  This helps ensure there are not duplicate includes,
+  and also helps ensure that headers are usable directly.
+
+* **DO** use `#pragma once` in all header files, rather than using ifdefs to test for duplicate inclusion.
+
+Style Guide
+-----------
+
+### Automated Formatting with `clang-format`
+
+For all C/C++ files (`*.c`, `*.cpp` and `*.h`), we use `clang-format` (specifically
+version 3.6) to apply our code formatting rules. After modifying C/C++ files and
+before merging, be sure to run:
+
+```sh
+$ ./scripts/format-code
+```
+
+This allows us to apply formatting choices such as the use of [Allman style](
+http://en.wikipedia.org/wiki/Indent_style#Allman_style) braces and the 80
+character column width consistently.
+
+Please stage the formatting changes with your commit, instead of making an extra
+"Format Code" commit. Your editor can likely be set up to automatically run
+`clang-format` across the file or region you're editing. See:
+
+- [clang-format.el](https://github.com/llvm-mirror/clang/blob/master/tools/clang-format/clang-format.el) for Emacs
+- [vim-clang-format](https://github.com/rhysd/vim-clang-format) for Vim
+- [vscode-cpptools](https://marketplace.visualstudio.com/items?itemName=ms-vscode.cpptools)
+  for Visual Studio Code
+
+The [.clang-format](../.clang-format) file describes the style that is enforced
+by the script, which is based off the LLVM style with modifications closer to
+the default Visual Studio style. See [clang-format style options](
+http://releases.llvm.org/3.6.0/tools/clang/docs/ClangFormatStyleOptions.html)
+for details.
+
+If you see unexpected formatting changes in the code, verify that you are running version 11 or higher of the LLVM tool-chain.
+
+### License Header
+
+The following license header **must** be included at the top of every new code file:
+
+```
+// Copyright (c) <Contributor>
+// SPDX-License-Identifier: Apache-2.0
+```
+
+It should be prefixed with the file's comment marker. If there is a compelling
+reason to not include this header, the file can be added to
+`.check-license.ignore`.
+
+All files are checked for this header with the script:
+
+```sh
+$ ./scripts/check-license
+```
+
+### Naming Conventions
+
+Naming conventions we use that are not automated include:
+
+1. Use `lower_snake_case` for variable, member/field, and function names.
+2. Use `UPPER_SNAKE_CASE` for macro names and constants.
+3. Prefer `lower_snake_case` file names for headers and sources.
+4. Prefer full words for names over contractions (i.e., `memory_context`, not
+   `mem_ctx`).
+5. Prefix names with `_` to indicate internal and private fields or methods
+   (e.g., `_internal_field, _internal_method()`).
+6. The single underscore (`_` ) is reserved for local definitions (static,
+   file-scope definitions).
+   e.g., static ubpf_result_t _do_something(..).
+7. Prefix `struct` definitions with `_` (this is an exception to point 6), and always create a `typedef` with the
+   suffix `_t`.  For example:
+```c
+typedef struct _ubpf_widget
+{
+    uint64_t count;
+} ubpf_widget_t;
+```
+8. Prefix uBPF specific names in the global namespace with `ubpf_` (e.g., `ubpf_result_t`).
+
+Above all, if a file happens to differ in style from these guidelines (e.g.,
+private members are named `m_member` rather than `_member`), the existing style
+in that file takes precedence.

scripts/.check-license.ignore

@@ -0,0 +1,25 @@
+# This file uses regular expressions, not shell globs!
+
+# File extensions that don't support embedding license info
+.*\.md$
+.*\.o$
+.*\.png$
+.*\.proj$
+.*\.rc$
+.*\.sln$
+.*\.vsdx$
+
+# Generated files
+tools/netsh/resource.h
+
+# Other Files
+LICENSE.txt
+Doxyfile
+\.check-license\.ignore
+\.clang-format
+\.gitattributes
+\.github/CODEOWNERS
+\.github/workflows/build.yml
+\.gitignore
+\.gitmodules
+packages.config

scripts/check-license.sh

@@ -0,0 +1,86 @@
+#!/usr/bin/env bash
+
+# Copyright (c) Microsoft Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+# This script accepts either a list of files relative to the current
+# working directory, or it will check all files tracked in Git. In
+# both cases, it ignores files matching any regular expression listed
+# in '.check-license.ignore'.
+
+set -o errexit
+set -o pipefail
+
+license=("Copyright" "SPDX-License-Identifier:")
+
+root=$(git rev-parse --show-toplevel)
+
+# If we are inside mingw* environment, then we update the path to proper format
+if [[ $(uname) == MINGW* ]] ; then
+      root=$(cygpath -u "${root}")
+fi
+
+ignore_res=()
+while IFS=$'\r' read -r i; do
+      if [[ $i =~ ^# ]] || [[ -z $i ]]; then # ignore comments
+          continue
+      fi
+      ignore_res+=("$i")
+done < "$root/scripts/.check-license.ignore"
+
+should_ignore() {
+    for re in "${ignore_res[@]}"; do
+        if [[ $1 =~ $re ]]; then
+            return
+        fi
+    done
+    false
+}
+
+# Create array of files to check, either from the given arguments or
+# all files in Git, ignore any that match a regex in the ignore file.
+files=()
+if [[ $# -ne 0 ]]; then
+    for f in "$@"; do
+        file=$(realpath -q "$f") || file=""
+
+        if [[ ! -f $file ]]; then # skip non-existent files
+            continue
+        fi
+
+        file=${file#$root/} # remove the prefix
+
+        if should_ignore "$file"; then
+            continue
+        fi
+
+        files+=("$file")
+    done
+else
+    # Find all files in Git. These are guaranteed to exist, to not be
+    # generated, and to not have the prefix.
+    cd "$root"
+    while IFS= read -r -d '' file; do
+        if should_ignore "$file"; then
+            continue
+        fi
+
+        files+=("$file")
+    done < <(git ls-files -z)
+fi
+
+failures=0
+for file in "${files[@]}"; do
+    for line in "${license[@]}"; do
+        # We check only the first four lines to avoid false positives
+        # (such as this script), but to allow for a shebang and empty
+        # line between it and the license.
+        if ! head -n4 "${root}/${file}" | grep --quiet --fixed-strings --max-count=1 "${line}"; then
+            echo "${file}" missing "${line}"
+            failures=$((failures + 1))
+            break
+        fi
+    done
+done
+
+exit $failures

scripts/commit-msg

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# Copyright (c) Microsoft Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+set -o errexit
+
+exit_() {
+    echo ""
+    echo "$1"
+    echo ""
+    echo "This hook can be skipped if needed with 'git commit --no-verify'"
+    echo "See '.git/hooks/commit-msg., installed from 'scripts/commit-msg'"
+    exit 1
+}
+
+sign_offs="$(grep '^Signed-off-by: ' "$1" || test $? = 1 )"
+
+if [[ -z $sign_offs ]]; then
+    exit_ "Commit failed: please sign-off on the DCO with 'git commit -s'"
+fi
+
+if [[ -n $(echo "$sign_offs" | sort | uniq -c | sed -e '/^[ 	]*1[ 	]/d') ]]; then
+    exit_ "Commit failed: please remove duplicate Signed-off-by lines"
+fi