Fix dangling FDs on Linux platforms

CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html),
 as of version 2.1.1.
 
+## [3.0.3] - 2023-04-22
+### Fixed
+- Fixed dangling file descriptors on linux platforms after calling `get_monitors()`.
+
 ## [3.0.2] - 2022-11-05
 ### Added
 - Added support for pyudev version 0.24.0.
@@ -78,7 +82,8 @@ as of version 2.1.1.
 - Added a changelog.
 
 
-[Unreleased]: https://github.com/newAM/monitorcontrol/compare/3.0.2...HEAD
+[Unreleased]: https://github.com/newAM/monitorcontrol/compare/3.0.3...HEAD
+[3.0.3]: https://github.com/newAM/monitorcontrol/compare/3.0.2...3.0.3
 [3.0.2]: https://github.com/newAM/monitorcontrol/compare/3.0.1...3.0.2
 [3.0.1]: https://github.com/newAM/monitorcontrol/compare/3.0.0...3.0.1
 [3.0.0]: https://github.com/newAM/monitorcontrol/compare/2.5.1...3.0.0

monitorcontrol/vcp/vcp_linux.py

@@ -56,20 +56,31 @@ def __init__(self, bus_number: int):
         self.logger = logging.getLogger(__name__)
         self.bus_number = bus_number
         self.fd: Optional[str] = None
-        self.fp = None
+        self.fp: str = f"/dev/i2c-{self.bus_number}"
         # time of last feature set call
         self.last_set: Optional[float] = None
 
     def __enter__(self):
+        def cleanup(fd: Optional[int]):
+            if fd is not None:
+                try:
+                    os.close(self.fd)
+                except OSError:
+                    pass
+
         try:
-            self.fp = f"/dev/i2c-{self.bus_number}"
             self.fd = os.open(self.fp, os.O_RDWR)
             fcntl.ioctl(self.fd, self.I2C_SLAVE, self.DDCCI_ADDR)
             self.read_bytes(1)
         except PermissionError as e:
+            cleanup(self.fd)
             raise VCPPermissionError(f"permission error for {self.fp}") from e
         except OSError as e:
+            cleanup(self.fd)
             raise VCPIOError(f"unable to open VCP at {self.fp}") from e
+        except Exception as e:
+            cleanup(self.fd)
+            raise e
         return self
 
     def __exit__(

pyproject.toml

@@ -5,7 +5,7 @@ target-version = ["py36", "py37", "py38"]
 [tool.poetry]
 name = "monitorcontrol"
 description = "Monitor controls using MCCS over DDC-CI."
-version = "3.0.2"
+version = "3.0.3"
 authors = ["Alex Martens <[email protected]>"]
 license = "MIT"
 readme = "README.rst"