cmake updates

CMakeLists.txt

@@ -1,20 +1,21 @@
-cmake_minimum_required(VERSION 3.24)
+cmake_minimum_required(VERSION 3.23)
 
 # Our C++ project ...
 project(bit DESCRIPTION "C++ classes for working in GF(2)" LANGUAGES CXX)
 
-# Add a target for the "library" we are building (bit is header only -- hence INTERFACE).
+# Add a target for the "library" we are building (${PROJECT_NAME} is header only -- hence INTERFACE).
 # Also add an alias that prepends a "namespace" -- if clients use that to link to, they get better error messages.
-add_library(bit INTERFACE)
-add_library(bit::bit ALIAS bit)
+add_library(${PROJECT_NAME} INTERFACE)
+add_library(${PROJECT_NAME}::${PROJECT_NAME} ALIAS ${PROJECT_NAME})
 
 # We use some C++20 features.
-target_compile_features(bit INTERFACE cxx_std_20)
+target_compile_features(${PROJECT_NAME} INTERFACE cxx_std_20)
 
-# Where to find the bit headers (e.g., how to resolve `#include <bit/bit.h>`).
-target_include_directories(bit INTERFACE
-    $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include/>
-    $<INSTALL_INTERFACE:include/bit>)
+# Where to find the headers (e.g., how to resolve `#include <bit/bit.h>`).
+target_sources(${PROJECT_NAME} INTERFACE
+    FILE_SET    library_headers
+    TYPE        HEADERS
+    BASE_DIRS   include/)
 
 # That's it unless we are developing the library instead of just using it.
 if (PROJECT_IS_TOP_LEVEL)
@@ -24,27 +25,25 @@ if (PROJECT_IS_TOP_LEVEL)
 
     # Prevent in-source builds for the example programs.
     include(disable_in_source_builds)
-    disable_in_source_builds()
 
     # Make the compiler issue warnings for "bad" code, etc.
     include(compiler_init)
-    compiler_init(bit)
+    compiler_init(${PROJECT_NAME})
 
     # Debug builds get the BIT_VERIFY flag set.
-    target_compile_definitions(bit INTERFACE $<$<CONFIG:Debug>: -DBIT_VERIFY>)
+    target_compile_definitions(${PROJECT_NAME} INTERFACE $<$<CONFIG:Debug>: -DBIT_VERIFY>)
 
     # For neatness, we put the example executables in build/bin/.
     include(GNUInstallDirs)
     set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR}")
 
-    # Our example programs use the header-only `utilities` library.
-    include(FetchContent)
-    FetchContent_Declare(utilities URL https://github.com/nessan/utilities/releases/download/current/utilities.zip)
-    FetchContent_MakeAvailable(utilities)
+    # Our example programs use the header-only `utilities` library -- grab the current version from GitHub.
+    include(fetch_content)
+    fetch_content(utilities URL https://github.com/nessan/utilities/releases/download/current/utilities.zip)
 
     # Walk through the examples/ directory and build a target for each .cpp file with appropriate linkage.
     # We have a CMake module that makes that traversal straightforward.
     include(add_executables)
-    add_executables(examples bit::bit utilities::utilities)
+    add_executables(examples ${PROJECT_NAME}::${PROJECT_NAME} utilities::utilities)
 
 endif()

cmake/add_executables.cmake

@@ -1,8 +1,8 @@
 # -----------------------------------------------------------------------------
 # @brief Add targets for lots of small executables.
-# @link  https://nessan.github.io/cmake
+# @link  https://nessan.github.io/cmake/
 #
-# SPDX-FileCopyrightText:  2023 Nessan Fitzmaurice <nzznfitz+gh@icloud.com>
+# SPDX-FileCopyrightText:  2023 Nessan Fitzmaurice <nessan.fitzmaurice@me.com>
 # SPDX-License-Identifier: MIT
 # -----------------------------------------------------------------------------
 
@@ -69,7 +69,7 @@ function(add_executables dir)
     foreach(source_file ${sources})
 
         # File "Foo03.cpp" is expected to yield target "Foo03" in the target variable
-        get_filename_component(target ${source_file} NAME_WLE)
+        cmake_path(GET source_file STEM target)
 
         # Might have a target naming conflict (test program Foo linking to library Foo)
         check_target(${target} clean_target)

cmake/disable_in_source_builds.cmake

@@ -1,8 +1,8 @@
 # -----------------------------------------------------------------------------
 # @brief Dsable in-source builds. A classic!
-# @link  https://nessan.github.io/cmake
+# @link  https://nessan.github.io/cmake/
 #
-# SPDX-FileCopyrightText:  2023 Nessan Fitzmaurice <nzznfitz+gh@icloud.com>
+# SPDX-FileCopyrightText:  2023 Nessan Fitzmaurice <nessan.fitzmaurice@me.com>
 # SPDX-License-Identifier: MIT
 # -----------------------------------------------------------------------------
 function(disable_in_source_builds)
@@ -18,4 +18,7 @@ function(disable_in_source_builds)
         of those or cmake will refuse to work.")
     endif()
 
-endfunction()
+endfunction()
+
+# Immediately run the function -- hust including this file should run it.
+disable_in_source_builds()

cmake/fetch_content.cmake

@@ -0,0 +1,18 @@
+# -----------------------------------------------------------------------------
+# @brief Wrapper around FetchContent.
+# @link  https://nessan.github.io/cmake/
+#
+# SPDX-FileCopyrightText:  2023 Nessan Fitzmaurice <[email protected]>
+# SPDX-License-Identifier: MIT
+# -----------------------------------------------------------------------------
+function(fetch_content)
+    include(FetchContent)
+    set(FETCHCONTENT_QUIET FALSE)
+    set(FETCHCONTENT_TRY_FIND_PACKAGE_MODE ALWAYS)
+    FetchContent_Declare(${ARGV}
+        GIT_SHALLOW 1
+        GIT_PROGRESS TRUE
+        SYSTEM
+    )
+    FetchContent_MakeAvailable(${ARGV0})
+endfunction()