Renamed check_header_existence function to get_header_file

This is because the function returns the path to the header file and not just whether is exists or not.
This change also caused separation of the function into a dedicated file

Author: MrPointer

cmake/Platform/Sources/HeaderExistanceChecker.cmake

@@ -1,23 +1,11 @@
-function(_check_header_existance _header_we _dir_list _return_var)
-
-    foreach (include_dir ${_dir_list})
-
-        find_header_files("${include_dir}" include_dir_headers RECURSE)
-
-        foreach (included_header ${include_dir_headers})
-            get_name_without_file_extension(${included_header} included_header_we)
-            if ("${included_header_we}" STREQUAL "${_header_we}")
-                set(_return_var ${included_header} PARENT_SCOPE)
-                return()
-            endif ()
-        endforeach ()
-
-    endforeach ()
-
-    set(_return_var NOTFOUND PARENT_SCOPE)
-
-endfunction()
-
+#=============================================================================#
+# Checks whether the given header name is discoverable by the given target,
+# i.e. whether it's part of the target's 'INCLUDE_DIRECTORIES' property.
+#       _header_we - Name of a header to check its' discoverability.
+#       _target_name - Name of a target to check discoverability against.
+#       _return_var - Name of variable in parent-scope holding the return value.
+#       Returns - True if discoverable, false otherwise.
+#=============================================================================#
 function(is_header_discoverable_by_target _header_we _target_name _return_var)
 
     # Get target's direct include dirs

cmake/Platform/Sources/HeaderRetriever.cmake

@@ -0,0 +1,29 @@
+#=============================================================================#
+# Retrieves full path to the file associated with the given header name,
+# which should be located under one of the directories in the given list.
+# The search is performed recursively (i.e. including sub-dirs) by default.
+# If the header can't be found, "NOTFOUND" string is returned.
+#       _header_we - Name of a header file which should be retrieved.
+#       _dir_list - List of directories which could contain the searched header file.
+#       _return_var - Name of variable in parent-scope holding the return value.
+#       Returns - Full path to the header file associated with the given header name, "NOTFOUND" if can't be found.
+#=============================================================================#
+function(get_header_file _header_we _dir_list _return_var)
+
+    foreach (include_dir ${_dir_list})
+
+        find_header_files("${include_dir}" include_dir_headers RECURSE)
+
+        foreach (included_header ${include_dir_headers})
+            get_name_without_file_extension(${included_header} included_header_we)
+            if ("${included_header_we}" STREQUAL "${_header_we}")
+                set(_return_var ${included_header} PARENT_SCOPE)
+                return()
+            endif ()
+        endforeach ()
+
+    endforeach ()
+
+    set(_return_var NOTFOUND PARENT_SCOPE)
+
+endfunction()

…m/Sources/IncludedHeadersRetriever.cmake …orm/Sources/SourceHeadersRetriever.cmakecmake/Platform/Sources/IncludedHeadersRetriever.cmake renamed to cmake/Platform/Sources/SourceHeadersRetriever.cmake cmake/Platform/Sources/IncludedHeadersRetriever.cmake renamed to cmake/Platform/Sources/SourceHeadersRetriever.cmake

@@ -48,7 +48,7 @@ function(get_source_headers _source_file _include_dirs _return_var)
 
     foreach (header ${included_headers})
 
-        _check_header_existance(${header} ${_include_dirs} header_path)
+        get_header_file(${header} ${_include_dirs} header_path)
         if (NOT header_path OR "${header_path}" MATCHES "NOTFOUND")
             continue()
         endif ()

cmake/Platform/Sources/Sources.cmake

@@ -1,5 +1,7 @@
 include(SourceSeeker)
 include(ExampleSourcesSeeker)
 include(ArduinoLibrarySourcesSeeker)
+include(HeaderRetriever)
 include(HeaderExistanceChecker)
-include(IncludedHeadersRetriever)
+include(SourceHeadersRetriever)
+include(SourcesManager)

cmake/Platform/Utilities/TargetUtils.cmake

@@ -0,0 +1,29 @@
+function(get_target_include_directories _target_name _return_var)
+
+    # Get target's direct include dirs
+    get_target_property(target_include_dirs ${_target_name} INCLUDE_DIRECTORIES)
+
+    # Get include dirs of targets linked to the given target
+    get_target_property(target_linked_libs ${_target_name} LINK_LIBRARIES)
+
+    # Explictly add include dirs of all linked libraries (given they're valid cmake targets)
+    foreach (linked_lib ${target_linked_libs})
+
+        if (NOT TARGET ${linked_lib}) # Might be a command-line linked library (such as 'm'/math)
+            continue()
+        endif ()
+
+        get_target_include_directories(${linked_lib} lib_include_dirs)
+        set(include_dirs ${lib_include_dirs}) # Update list with recursive call results
+
+    endforeach ()
+
+    if (NOT "${target_include_dirs}" MATCHES "NOTFOUND") # Target has direct include dirs
+        list(APPEND include_dirs ${target_include_dirs})
+    endif ()
+
+    list(REMOVE_DUPLICATES include_dirs)
+
+    set(${_return_var} ${include_dirs} PARENT_SCOPE)
+
+endfunction()

cmake/Platform/Utilities/Utilities.cmake

@@ -4,5 +4,6 @@ include(StringUtils)
 include(PathUtils)
 include(PropertyUtils)
 include(LibraryUtils)
+include(TargetUtils)
 include(PlatformLibraryUtils)
 include(CMakeArgumentsUtils)