FindRust upgrades, integrate c/bindgen w. build.rs

`FindRust.cmake` no longer attempts to guess at the Rust platform target
triple by evaluating the OS, Architecture, and pointer-size of the target except
on Windows (for cross-compiling to x86) and on macOS (for universal binary builds).
Instead, it uses Rust's host target triple obtained with the
command `rustc -vV`.
If you want to cross-compile, you can set the `RUST_COMPILER_TARGET`
variable.

`FindRust.cmake` now sets the Rust build type to Release for CMake's
MinSizeRel and RelWithDebInfo builds, using the `-g` RUSTFLAG for the
latter so that debug symbols are provided.

Renamed a bunch of things to make it more intuitive. Namely the demo
library is now called "demo" instead of "CMakeRust", and the C and Rust
sources are now in separate directories such that the Rust stuff follows
the traditional Rust project layout.

Demo now integrates the bindgen and cbindgen processes into a `build.rs`
file that automatically runs at build time and does not depend on having
bindgen or cbindgen pre-installed. Generating C bindings with cbindgen
works everywhere, but generating the Rust bindings from the C code
appears to require libclang and may not be present on all systems - so
we only run it when MAINTAINER_MODE is ON.

Demo now installs the Rust-built static library.

The demo app is linked with the static libs so we don't have to make
a temporary install on Windows so the app can load the DLL.
Similarly, we link with the static libs for Rust unit test executable, so we
don't need a temporary install to run the test executable.

Also add clang-format spec for convenience in maintaining the C bits.

For Github Actions: switched to using CMake manually.

.clang-format

@@ -0,0 +1,148 @@
+---
+Language:        Cpp
+AccessModifierOffset: -2
+AlignAfterOpenBracket: Align
+AlignConsecutiveMacros: false
+AlignConsecutiveAssignments: true
+AlignConsecutiveBitFields: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands:   Align
+AlignTrailingComments: true
+AllowAllArgumentsOnNextLine: true
+AllowAllConstructorInitializersOnNextLine: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortEnumsOnASingleLine: true
+AllowShortBlocksOnASingleLine: Never
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortLambdasOnASingleLine: All
+AllowShortIfStatementsOnASingleLine: WithoutElse
+AllowShortLoopsOnASingleLine: true
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: MultiLine
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterCaseLabel:  false
+  AfterClass:      true
+  AfterControlStatement: Never
+  AfterEnum:       false
+  AfterFunction:   true
+  AfterNamespace:  true
+  AfterObjCDeclaration: false
+  AfterStruct:     false
+  AfterUnion:      false
+  AfterExternBlock: false
+  BeforeCatch:     false
+  BeforeElse:      false
+  BeforeLambdaBody: false
+  BeforeWhile:     false
+  IndentBraces:    false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Linux
+BreakBeforeInheritanceComma: false
+BreakInheritanceList: BeforeColon
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeColon
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: true
+ColumnLimit:     0
+CommentPragmas:  '^ IWYU pragma:'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+Cpp11BracedListStyle: true
+DeriveLineEnding: true
+DerivePointerAlignment: true
+DisableFormat:   false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IncludeBlocks:   Preserve
+IncludeCategories:
+  - Regex:           '^"(llvm|llvm-c|clang|clang-c)/'
+    Priority:        2
+    SortPriority:    0
+  - Regex:           '^(<|"(gtest|gmock|isl|json)/)'
+    Priority:        3
+    SortPriority:    0
+  - Regex:           '.*'
+    Priority:        1
+    SortPriority:    0
+IncludeIsMainRegex: '(Test)?$'
+IncludeIsMainSourceRegex: ''
+IndentCaseLabels: true
+IndentCaseBlocks: false
+IndentGotoLabels: true
+IndentPPDirectives: None
+IndentExternBlock: AfterExternBlock
+IndentWidth:     4
+IndentWrappedFunctionNames: false
+InsertTrailingCommas: None
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: true
+MacroBlockBegin: ''
+MacroBlockEnd:   ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 2
+ObjCBreakBeforeNestedBlockParam: true
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakAssignment: 2
+PenaltyBreakBeforeFirstCallParameter: 19
+PenaltyBreakComment: 300
+PenaltyBreakFirstLessLess: 120
+PenaltyBreakString: 1000
+PenaltyBreakTemplateDeclaration: 10
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 60
+PointerAlignment: Right
+ReflowComments:  true
+SortIncludes:    false
+SortUsingDeclarations: true
+SpaceAfterCStyleCast: false
+SpaceAfterLogicalNot: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCpp11BracedList: false
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyBlock: false
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles:  false
+SpacesInConditionalStatement: false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+SpaceBeforeSquareBrackets: false
+Standard:        Latest
+StatementMacros:
+  - Q_UNUSED
+  - QT_REQUIRE_VERSION
+TabWidth:        8
+UseCRLF:         false
+UseTab:          Never
+WhitespaceSensitiveMacros:
+  - STRINGIZE
+  - PP_STRINGIZE
+  - BOOST_PP_STRINGIZE
+...
+

.github/workflows/main.yml

@@ -4,14 +4,14 @@ name: Build Test
 # events but only for the main branch
 on:
   push:
-    branches: [ main ]
+    branches: [main]
   pull_request:
-    branches: [ main ]
+    branches: [main]
 
 # A workflow run is made up of one or more jobs that can run sequentially or in parallel
 jobs:
   build_and_test:
-    name: '${{ matrix.os }}: build and test'
+    name: "${{ matrix.os }}: build and test"
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
@@ -29,24 +29,23 @@ jobs:
       - name: get-cmake
         uses: lukka/get-cmake@latest
 
-      - name: run-cmake
-        uses: lukka/[email protected]
-        with:
-          cmakeGenerator: 'Ninja'
-          cmakeListsOrSettingsJson: 'CMakeListsTxtBasic'
-          buildDirectory: '${{ runner.workspace }}/build/ninja/'
+      - name: Build project
+        working-directory: "${{ runner.workspace }}/"
+        run: |
+          cmake -B ./build -S ./cmake-rust-demo
+          cmake --build ./build
 
       - name: Run tests
-        working-directory: '${{ runner.workspace }}/build/ninja/'
+        working-directory: "${{ runner.workspace }}/build/"
         run: |
           ctest -VV
 
       - name: Run the app
         run: |
-          ${{ runner.workspace }}/build/ninja/app/app
+          ${{ runner.workspace }}/build/app/app
 
   build_and_test_windows:
-    name: 'windows-latest: build and test'
+    name: "windows-latest: build and test"
     runs-on: windows-latest
 
     steps:
@@ -60,18 +59,17 @@ jobs:
       - name: get-cmake
         uses: lukka/get-cmake@latest
 
-      - name: run-cmake
-        uses: lukka/[email protected]
-        with:
-          cmakeGenerator: 'VS16Win64'
-          cmakeListsOrSettingsJson: 'CMakeListsTxtBasic'
-          buildDirectory: '${{ runner.workspace }}/build/vs2019/'
+      - name: Build project
+        working-directory: "${{ runner.workspace }}/"
+        run: |
+          cmake -B ./build -S ./cmake-rust-demo -A x64
+          cmake --build ./build
 
       - name: Run tests
-        working-directory: '${{ runner.workspace }}/build/vs2019/'
+        working-directory: "${{ runner.workspace }}/build/"
         run: |
           ctest -VV -C Debug
 
       - name: Run the app
         run: |
-          ${{ runner.workspace }}\\build\\vs2019\\app\\Debug\\app.exe
+          ${{ runner.workspace }}\\build\\app\\Debug\\app.exe

.gitignore

@@ -88,3 +88,4 @@ build/*
 
 # Rust / Cargo files
 Cargo.lock
+target/*

CMakeLists.txt

@@ -1,10 +1,11 @@
-# Copyright (C) 2020 Micah Snyder.
+# Copyright (C) 2020-2022 Micah Snyder.
 
 cmake_minimum_required(VERSION 3.18)
+set(RUSTC_MINIMUM_REQUIRED 1.56)
 
-project( RustCMakeDemo
-         VERSION "0.1.0"
-         DESCRIPTION "A demo app to show a CMake project with components written in Rust." )
+project(RustCMakeDemo
+        VERSION "0.2.0"
+        DESCRIPTION "A demo app to show a CMake project with components written in Rust.")
 
 set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake" ${CMAKE_MODULE_PATH})
 
@@ -16,14 +17,14 @@ option(MAINTAINER_MODE
     "Use `cbindgen` to generate Rust library API headers."
     ${MAINTAINER_MODE_DEFAULT})
 
-if(MAINTAINER_MODE)
-    set(cbindgen_REQUIRED 1)
-endif()
 find_package(Rust REQUIRED)
 
 # Always use '-fPIC'/'-fPIE' option.
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
+# Include GNUInstallDirs for access to CMAKE_INSTALL_LIBDIR, etc
+include(GNUInstallDirs)
+
 # Enable CTest
 if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
     include(CTest)
@@ -44,9 +45,10 @@ include(CPack)
 #
 # Build targets.
 #
-add_subdirectory( lib )
-add_subdirectory( common )
-add_subdirectory( app )
+add_subdirectory(lib)
+add_subdirectory(common)
+add_subdirectory(app)
+add_subdirectory(test)
 
 #
 # The Summary Info.
@@ -58,10 +60,7 @@ message(STATUS "Configuration Options Summary --
         Build type:         ${CMAKE_BUILD_TYPE}
         C compiler:         ${CMAKE_C_COMPILER}
         Rust toolchain:     ${cargo_EXECUTABLE} (${cargo_VERSION})
+                            ${rustc_EXECUTABLE} (${rustc_VERSION})
         CFLAGS:             ${CMAKE_C_FLAGS_${_build_type}} ${CMAKE_C_FLAGS}
     Build Options:
         Maintainer Mode:    ${MAINTAINER_MODE}")
-if(MAINTAINER_MODE)
-message("\
-        cbindgen:           ${cbindgen_EXECUTABLE} (${cbindgen_VERSION})")
-endif()

Cargo.toml

@@ -0,0 +1,6 @@
+[workspace]
+
+members = ["lib/rust", "common/gen_uuid"]
+
+[profile.dev.package."*"]
+opt-level = 2