Fix crash with container closing with GC

.github/workflows/smoke.yml

@@ -38,7 +38,6 @@ jobs:
           - {os: ubuntu-24.04, python: "3.12", ffmpeg: "8.0.1", extras: true}
           - {os: ubuntu-24.04, python: "3.10", ffmpeg: "8.0.1"}
           - {os: ubuntu-24.04, python: "3.13", ffmpeg: "8.1"}
-          - {os: ubuntu-24.04, python: "pypy3.11", ffmpeg: "8.0.1"}
           - {os: macos-14, python: "3.11", ffmpeg: "8.0.1"}
           - {os: macos-14, python: "3.14", ffmpeg: "8.1"}
 

av/container/core.pxd

@@ -1,4 +1,5 @@
 cimport libav as lib
+from libc.stdint cimport uint8_t
 
 from av.codec.hwaccel cimport HWAccel
 from av.container.pyio cimport PyIOFile
@@ -14,16 +15,13 @@ ctypedef struct timeout_info:
 
 
 cdef class Container:
-    cdef readonly bint writeable
     cdef lib.AVFormatContext *ptr
-
     cdef readonly object name
     cdef readonly str metadata_encoding
     cdef readonly str metadata_errors
 
     cdef readonly PyIOFile file
     cdef int buffer_size
-    cdef bint input_was_opened
     cdef readonly object io_open
     cdef readonly object open_files
 
@@ -39,6 +37,7 @@ cdef class Container:
     cdef readonly dict metadata
 
     # Private API.
+    cdef uint8_t _myflag  # enum: writeable, input_was_opened, started, done
     cdef _assert_open(self)
     cdef int err_check(self, int value) except -1
 

av/container/core.py

@@ -246,8 +246,8 @@ def __cinit__(
         if sentinel is not _cinit_sentinel:
             raise RuntimeError("cannot construct base Container")
 
-        self.writeable = isinstance(self, OutputContainer)
-        if not self.writeable and not isinstance(self, InputContainer):
+        writeable: cython.bint = isinstance(self, OutputContainer)
+        if not writeable and not isinstance(self, InputContainer):
             raise RuntimeError("Container cannot be directly extended.")
 
         if isinstance(file_, str):
@@ -276,13 +276,13 @@ def __cinit__(
                 format_name, acodec = format_name.split(":")
             self.format = ContainerFormat(format_name)
 
-        self.input_was_opened = False
         res: cython.int
         name_obj: bytes = os.fsencode(self.name)
         name: cython.p_char = name_obj
         ofmt: cython.pointer[cython.const[lib.AVOutputFormat]]
 
-        if self.writeable:
+        if writeable:
+            self._myflag |= 1  # enum.writeable = True
             ofmt = (
                 self.format.optr
                 if self.format
@@ -320,7 +320,7 @@ def __cinit__(
         # Setup Python IO.
         self.open_files = {}
         if not isinstance(file_, basestring):
-            self.file = PyIOFile(file_, buffer_size, self.writeable)
+            self.file = PyIOFile(file_, buffer_size, writeable)
             self.ptr.pb = self.file.iocontext
 
         if io_open is not None:
@@ -330,7 +330,7 @@ def __cinit__(
 
         ifmt: cython.pointer[cython.const[lib.AVInputFormat]]
         c_options: Dictionary
-        if not self.writeable:
+        if not writeable:
             ifmt = self.format.iptr if self.format else cython.NULL
             c_options = Dictionary(self.options, self.container_options)
 
@@ -342,7 +342,7 @@ def __cinit__(
                 )
             self.set_timeout(None)
             self.err_check(res)
-            self.input_was_opened = True
+            self._myflag |= 2  # enum.input_was_opened = True
 
         if format_name is None:
             self.format = build_container_format(self.ptr.iformat, self.ptr.oformat)
@@ -400,6 +400,10 @@ def flags(self, value: cython.int):
         self._assert_open()
         self.ptr.flags = value
 
+    @property
+    def input_was_opened(self):
+        return self._myflag & 2
+
     def chapters(self):
         self._assert_open()
         result: list = []

av/container/core.pyi

@@ -75,13 +75,11 @@ class Chapter(TypedDict):
     metadata: dict[str, str]
 
 class Container:
-    writeable: bool
     name: str
     metadata_encoding: str
     metadata_errors: str
     file: Any
     buffer_size: int
-    input_was_opened: bool
     io_open: Any
     open_files: Any
     format: ContainerFormat
@@ -100,6 +98,8 @@ class Container:
         exc_val: BaseException | None,
         exc_tb: TracebackType | None,
     ) -> None: ...
+    @property
+    def input_was_opened(self) -> bool: ...
     def close(self) -> None: ...
     def chapters(self) -> list[Chapter]: ...
     def set_chapters(self, chapters: list[Chapter]) -> None: ...

av/container/input.pxd

@@ -5,5 +5,4 @@ from av.stream cimport Stream
 
 
 cdef class InputContainer(Container):
-
     cdef flush_buffers(self)

av/container/input.py

@@ -13,11 +13,11 @@
 @cython.cfunc
 def close_input(self: InputContainer):
     self.streams = StreamContainer()
-    if self.input_was_opened:
-        with cython.nogil:
+    with cython.nogil:
+        if self._myflag & 2:
             # This causes `self.ptr` to be set to NULL.
             lib.avformat_close_input(cython.address(self.ptr))
-        self.input_was_opened = False
+            self._myflag &= ~2  # enum.input_was_opened = False
 
 
 @cython.cclass

av/container/output.pxd

@@ -5,8 +5,5 @@ from av.stream cimport Stream
 
 
 cdef class OutputContainer(Container):
-    cdef bint _started
-    cdef bint _done
     cdef lib.AVPacket *packet_ptr
-
     cpdef start_encoding(self)

av/container/output.py

@@ -15,16 +15,16 @@
 @cython.cfunc
 def close_output(self: OutputContainer):
     self.streams = StreamContainer()
-    if self._started and not self._done:
+    if self._myflag & 12 == 4:  # enum.started and not enum.done
         # We must only ever call av_write_trailer *once*, otherwise we get a
         # segmentation fault. Therefore no matter whether it succeeds or not
-        # we must absolutely set self._done.
+        # we must absolutely set enum.done.
         try:
             self.err_check(lib.av_write_trailer(self.ptr))
         finally:
             if self.file is None and not (self.ptr.oformat.flags & lib.AVFMT_NOFILE):
                 lib.avio_closep(cython.address(self.ptr.pb))
-            self._done = True
+            self._myflag |= 8  # enum.done = True
 
 
 @cython.cclass
@@ -35,8 +35,13 @@ def __cinit__(self, *args, **kwargs):
         with cython.nogil:
             self.packet_ptr = lib.av_packet_alloc()
 
+    def __del__(self):
+        try:
+            close_output(self)
+        except Exception:
+            pass
+
     def __dealloc__(self):
-        close_output(self)
         with cython.nogil:
             lib.av_packet_free(cython.address(self.packet_ptr))
 
@@ -426,7 +431,7 @@ def add_data_stream(self, codec_name=None, options: dict | None = None):
     @cython.ccall
     def start_encoding(self):
         """Write the file header! Called automatically."""
-        if self._started:
+        if self._myflag & 4:  # started
             return
 
         # TODO: This does NOT handle options coming from 3 sources.
@@ -486,7 +491,7 @@ def start_encoding(self):
             log = logging.getLogger(__name__)
             log.warning("Some options were not used: %s" % unused_options)
 
-        self._started = True
+        self._myflag |= 4
 
     @property
     def supported_codecs(self):

tests/test_open.py

@@ -1,3 +1,5 @@
+import gc
+import io
 from pathlib import Path
 
 import av
@@ -35,3 +37,19 @@ def test_str_output() -> None:
 
     container = av.open(path, "w")
     assert type(container) is av.container.OutputContainer
+
+
+def _container_no_close() -> None:
+    buf = io.BytesIO()
+    container = av.open(buf, mode="w", format="mp4")
+    stream = container.add_stream("mpeg4", rate=24)
+    stream.width = 320
+    stream.height = 240
+    stream.pix_fmt = "yuv420p"
+    container.start_encoding()
+
+
+def test_container_no_close() -> None:
+    # Do not close so that container is freed through GC.
+    _container_no_close()
+    gc.collect()