Add support for out-of-source builds

Signed-off-by: Ted Lyngmo <ted@lyncon.se>

Author: TedLyngmo

.gitignore

@@ -2,6 +2,7 @@
 *.d
 
 # Compiled Object files
+build
 *.slo
 *.lo
 *.o

CMakeLists.txt

@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 3.19)
+project(CloCXX)
+
+set(GENERATED_HEADER ${CMAKE_BINARY_DIR}/clocxx.hpp)
+
+add_executable(mkclocxx mkclocxx.cpp)
+
+add_custom_command(
+  OUTPUT ${GENERATED_HEADER}
+  COMMAND ./mkclocxx ${CMAKE_SOURCE_DIR}
+  DEPENDS mkclocxx
+)
+
+add_library(clocxx INTERFACE ${GENERATED_HEADER})
+
+install(
+    FILES ${GENERATED_HEADER}
+    DESTINATION ${CMAKE_INSTALL_PREFIX}/include
+)

Makefile

@@ -1,6 +1,8 @@
 LIB := $(shell $(CXX) -print-file-name=libstdc++.so)
 STDLIB := $(shell realpath -e "$(LIB)")
 STDDIR := $(shell dirname "$(STDLIB)")
+MAKEFILEPATH := $(abspath $(lastword $(MAKEFILE_LIST)))
+MAKEFILEDIR := $(dir $(MAKEFILEPATH))
 
 CXXOPT := -std=c++17 -O3 -Wall -Wextra -pedantic-errors
 
@@ -10,7 +12,7 @@ clocxx.hpp: mkclocxx mkclocxx.cpp base.hpp seen_clockid_t
 mkclocxx: mkclocxx.cpp clock_test_driver.cpp Makefile
 	$(CXX) $(CXXOPT) -o $@ $< -Wl,-rpath $(STDDIR)
 
-clock_test_driver: clock_test_driver.cpp
+clock_test_driver: $(MAKEFILEDIR)clock_test_driver.cpp
 	$(CXX) $(CXXOPT) -DCLOCK_TO_TEST=$(CLOCK_TO_TEST) -o $@ $<
 
 clean:

README.md

@@ -1,11 +1,20 @@
 # CloCXX
 A header only C++ library with `std::chrono` compatible clocks satisfying the _TrivialClock_ requirement 
 
-#### Building the `clocxx.hpp` header
-```
+#### Building the `clocxx.hpp` header in-source
+```bash
 make
 ```
 
+#### Building and installing the `clocxx.hpp` header out-of-source
+
+This will build `clocxx.hpp` and install it in `~/.local/include`:
+```bash
+cmake --install-prefix ~/.local -S . -B build
+cmake --build build
+cmake --install build
+```
+
 #### About
 
 `CloCXX` comes with a file with recipes named `seen_clockid_t`. This contains the `clockid_t` macro name, a `bool` describing if the clock is steady or not and finally a description of the clock. When building the `clocxx.hpp` header, each recipe will be checked individually and only working clock definitions will be included in the generated header file. In addition to the `typedef`s required to be a _TrivialClock_, each `lyn::chrono` clock comes with two additional constants:

mkclocxx.cpp

@@ -73,9 +73,10 @@ std::optional<pres> command(std::string command) {
     return pres{::pclose(pip), std::move(buf)};
 }
 
-result test(const clockdef& cd, int width) {
+result test(const std::filesystem::path& source_dir, const clockdef& cd, int width) {
     std::cout << "Clock under test: " << std::setw(width) << cd.macro;
-    auto res = command("make clock_test_driver CLOCK_TO_TEST=" + cd.macro);
+    std::string cmd = "make -f '" + source_dir.string() + "/Makefile' clock_test_driver CLOCK_TO_TEST=" + cd.macro;
+    auto res = command(cmd);
     if(not res || (*res).exitstatus) return UNSUPP;
 
     res = command("./clock_test_driver");
@@ -93,8 +94,8 @@ std::string mkname(std::string macro) {
     return macro.substr(6) + "_clock";
 }
 
-int createit() {
-    auto& seen_file = "seen_clockid_t";
+int createit(std::filesystem::path source_dir) {
+    auto seen_file = source_dir / "seen_clockid_t";
     std::cout << std::boolalpha;
     std::ifstream cids(seen_file);
     if(not cids) {
@@ -107,10 +108,10 @@ int createit() {
         return 1;
     }
     int maxwidth = std::max_element(cds.begin(), cds.end(), [](const clockdef& lhs, const clockdef& rhs) {
-        return lhs.macro.size() < rhs.macro.size();
-    })->macro.size();
+                       return lhs.macro.size() < rhs.macro.size();
+                   })->macro.size();
 
-    std::filesystem::copy("base.hpp", "clocxx.hpp", std::filesystem::copy_options::overwrite_existing);
+    std::filesystem::copy(source_dir / "base.hpp", "clocxx.hpp", std::filesystem::copy_options::overwrite_existing);
 
     auto& target = "clocxx.hpp";
     std::ofstream ofs(target, std::ios::app);
@@ -121,7 +122,7 @@ int createit() {
     ofs << std::boolalpha;
 
     for(auto& cd : cds) {
-        auto rv = test(cd, maxwidth);
+        auto rv = test(source_dir, cd, maxwidth);
         std::cout << ": " << rv << '\n';
         if(rv != UNSUPP) {
             auto clname = mkname(cd.macro);
@@ -134,8 +135,8 @@ int createit() {
     return 0;
 }
 
-int main() {
-    int rv = createit();
+int main(int argc, char* argv[]) {
+    int rv = createit(argc == 2 ? argv[1] : ".");
     if(rv == 0) {
         return system("clang-format -i clocxx.hpp");
     }