[reactos] 02/02: [CMAKE] Fix problem with __RELFILE__ not working when compiler uses relative pathes

[Timo Kreuzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=3de04ccace7d0b501608b6...

commit 3de04ccace7d0b501608b633ff2f02113728eb95
Author:     Timo Kreuzer [e-mail]
AuthorDate: Sun Dec 9 17:51:50 2018 +0100
Commit:     Timo Kreuzer [e-mail]
CommitDate: Tue Dec 11 21:50:58 2018 +0100

[CMAKE] Fix problem with __RELFILE__ not working when compiler uses relative pathes

This usually happens when the build dir is a subdir of the source dir. It is now detected during runtime, using the length of the relative path from the build dir to the source dir as the length of the prefix to skip, if __FILE__ starts with a '.'.
    Also fix the escaping of REACTOS_*_DIR defines. It was gracefully fixed up by CMake, but resulted in broken syntax highliting.

CORE-14839 #resolve
---
 CMakeLists.txt | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d2e8b861ee..c931d018da 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,9 +57,14 @@ endif()
 include(sdk/cmake/compilerflags.cmake)

add_definitions(-D__REACTOS__)
-add_definitions(-DREACTOS_SOURCE_DIR="\"${REACTOS_SOURCE_DIR}\"")
-add_definitions(-DREACTOS_BINARY_DIR="\"${REACTOS_BINARY_DIR}\"")
-add_compile_flags(-D__RELFILE__="&__FILE__[sizeof REACTOS_SOURCE_DIR]")
+
+# Double escape, since CMake unescapes before putting it on the command-line, where it's unescaped again by GCC/CL.
+add_definitions(-DREACTOS_SOURCE_DIR="\"${REACTOS_SOURCE_DIR}\"")
+add_definitions(-DREACTOS_BINARY_DIR="\"${REACTOS_BINARY_DIR}\"")
+
+# There doesn't seem to be a standard for __FILE__ being relative or absolute, so detect it at runtime.
+file(RELATIVE_PATH _PATH_PREFIX ${REACTOS_BINARY_DIR} ${REACTOS_SOURCE_DIR})
+add_compile_flags(-D__RELFILE__="&__FILE__[__FILE__[0] == '.' ? sizeof \"${_PATH_PREFIX}\" - 1 : sizeof REACTOS_SOURCE_DIR]")

if(MSVC_IDE)
     add_compile_flags("/MP")