respect CPATH/C_INCLUDE_PATH

Flags are hard to pass when python-evdev is installed as part of another
python library. Instead evdev should check standard environment
variables that also a C compiler would use to locate a header file.

See: https://gcc.gnu.org/onlinedocs/cpp/Environment-Variables.html

Update setup.py

Co-authored-by: Tobi <[email protected]>

setup.py

@@ -64,11 +64,14 @@
 #-----------------------------------------------------------------------------
 def create_ecodes(headers=None):
  if not headers:
- headers = [
- '/usr/include/linux/input.h',
- '/usr/include/linux/input-event-codes.h',
- '/usr/include/linux/uinput.h',
- ]
+ include_paths = set()
+ if os.environ.get("CPATH", "").strip() != "":
+ include_paths.update(os.environ["CPATH"].split(":"))
+ if os.environ.get("C_INCLUDE_PATH", "").strip() != "":
+ include_paths.update(os.environ["C_INCLUDE_PATH"].split(":"))
+ include_paths.add("/usr/include")
+ files = ["linux/input.h", "linux/input-event-codes.h", "linux/uinput.h"]
+ headers = [os.path.join(path, file) for path in include_paths for file in files]
 
  headers = [header for header in headers if os.path.isfile(header)]
  if not headers: