build: Refactor CMake back to in-tree CMakeListsbe

This moves the build definitions back to src/ subdirectories
(CMakeLists.txt per component). Configuration and dependencies are
kept out of tree. Configuration options are bundled into cmake/config/
modules. Dependencies are grouped by component (system/, crypt/, eth/,
coverage/, etc.). It now consistently uses target-based commands
(target_include_directories, target_link_libraries) instead of global
include_directories(). Proper PRIVATE/PUBLIC visibility for executable
link libraries. CONFIG_OUROBOROS_DEBUG now properly set based on being
a valid debug config (not just checking the string name).

It also adds OuroborosTargets export for find_package() support and
CMake package config files (OuroborosConfig.cmake) for easier
integration with CMake projects.

The build logic now follows more idiomatic CMake practices with
configuration separated from target definitions.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 44 insertions, 0 deletions

diff --git a/cmake/dependencies/system/fuse.cmake b/cmake/dependencies/system/fuse.cmake
new file mode 100644
index 00000000..7de12b31
--- /dev/null
+++ b/cmake/dependencies/system/fuse.cmake
@@ -0,0 +1,44 @@
+# Try pkg-config first, fall back to find_library
+if(PkgConfig_FOUND)
+  pkg_check_modules(FUSE QUIET IMPORTED_TARGET fuse>=2.6)
+  if(FUSE_FOUND AND NOT TARGET Fuse::Fuse)
+    add_library(Fuse::Fuse ALIAS PkgConfig::FUSE)
+  endif()
+endif()
+
+if(NOT FUSE_FOUND)
+  find_library(FUSE_LIBRARIES fuse QUIET)
+  if(FUSE_LIBRARIES)
+    set(FUSE_FOUND TRUE)
+    if(NOT TARGET Fuse::Fuse)
+      add_library(Fuse::Fuse UNKNOWN IMPORTED)
+      set_target_properties(Fuse::Fuse PROPERTIES
+        IMPORTED_LOCATION "${FUSE_LIBRARIES}")
+    endif()
+  endif()
+endif()
+
+if(FUSE_FOUND)
+  set(DISABLE_FUSE FALSE CACHE BOOL "Disable FUSE support")
+  if(NOT DISABLE_FUSE)
+    if(FUSE_VERSION)
+      message(STATUS "FUSE support enabled (version ${FUSE_VERSION})")
+    else()
+      message(STATUS "FUSE support enabled")
+    endif()
+    # FUSE_PREFIX is set in cmake/config/global.cmake
+    set(HAVE_FUSE TRUE CACHE INTERNAL "FUSE filesystem support available")
+  else()
+    message(STATUS "FUSE support disabled by user")
+    unset(HAVE_FUSE CACHE)
+  endif()
+else()
+  message(STATUS "Install FUSE version >= 2.6 to enable RIB access")
+  unset(HAVE_FUSE CACHE)
+endif()
+
+if(NOT HAVE_FUSE)
+  set(FUSE_LIBRARIES "")
+endif()
+
+mark_as_advanced(FUSE_LIBRARIES)