Add pxdpad, a .pxd layout linter

.github/workflows/smoke.yml

@@ -26,8 +26,15 @@ jobs:
         with:
           activate-environment: true
           python-version: "3.14"
+      - name: Nim
+        uses: jiro4989/setup-nim-action@v2
+        with:
+          nim-version: "stable"
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
       - name: Linters
         run: make lint
+      - name: pxdpad
+        run: make pxdpad
 
   nix:
     name: "py-${{ matrix.config.python }} lib-${{ matrix.config.ffmpeg }} ${{matrix.config.os}}"

Makefile

@@ -7,11 +7,10 @@ PYTHON := $(PYAV_PYTHON)
 PIP := $(PYAV_PIP)
 
 
-.PHONY: default build clean fate-suite lint test
+.PHONY: default build clean fate-suite lint test pxdpad pxdpad-build
 
 default: build
 
-
 build:
 	$(PIP) install -U --pre cython setuptools
 	CFLAGS=$(CFLAGS) LDFLAGS=$(LDFLAGS) $(PYTHON) setup.py build_ext --inplace --debug
@@ -34,6 +33,12 @@ lint:
 	isort --check-only --diff av examples tests
 	mypy av tests
 
+pxdpad-build:
+	nim c -d:danger --hints:off -o:tools/pxdpad/bin/pxdpad tools/pxdpad/src/main.nim
+
+pxdpad: pxdpad-build
+	tools/pxdpad/bin/pxdpad av include
+
 test:
 	$(PIP) install --group test
 	$(PYTHON) -m pytest

av/codec/hwaccel.pxd

@@ -11,9 +11,9 @@ cdef class HWConfig:
 cdef HWConfig wrap_hwconfig(const lib.AVCodecHWConfig *ptr)
 
 cdef class HWDevice:
-    cdef int _device_type
     cdef lib.AVBufferRef *ptr
     cdef readonly dict options
+    cdef int _device_type
     cdef readonly int flags
 
 cdef class HWAccel:

tools/pxdpad/.gitignore

@@ -0,0 +1,4 @@
+bin/
+nimcache/
+*.exe
+tests/test_pxdpad

tools/pxdpad/src/abi.nim

@@ -0,0 +1,119 @@
+## Target ABIs and the built-in type table.
+
+import std/[strutils, sets]
+import model
+
+const
+  targetNames* = ["lp64", "darwin-arm64", "llp64", "armv7", "ilp32"]
+
+proc getTarget*(name: string): Target =
+  ## `lp64` is the x86-64 System V ABI, `llp64` is 64-bit Windows.
+  case name.toLowerAscii
+  of "lp64", "linux", "sysv":  # x86-64 System V
+    Target(name: "lp64", ptrSize: 8, ptrAlign: 8, longSize: 8, longAlign: 8,
+           ldSize: 16, ldAlign: 16, maxScalarAlign: 8, headSize: 16)
+  of "darwin-arm64", "macos", "arm64":
+    Target(name: "darwin-arm64", ptrSize: 8, ptrAlign: 8, longSize: 8, longAlign: 8,
+           ldSize: 8, ldAlign: 8, maxScalarAlign: 8, headSize: 16)
+  of "llp64", "windows", "win64":
+    Target(name: "llp64", ptrSize: 8, ptrAlign: 8, longSize: 4, longAlign: 4,
+           ldSize: 8, ldAlign: 8, maxScalarAlign: 8, headSize: 16)
+  of "armv7", "armhf", "armv7l":  # 32-bit ARM, arm-linux-gnueabihf
+    # ILP32 like i386, but AAPCS aligns double and long long to 8, and
+    # long double is just double.
+    Target(name: "armv7", ptrSize: 4, ptrAlign: 4, longSize: 4, longAlign: 4,
+           ldSize: 8, ldAlign: 8, maxScalarAlign: 8, headSize: 8)
+  of "ilp32", "x86":           # 32-bit x86 System V
+    Target(name: "ilp32", ptrSize: 4, ptrAlign: 4, longSize: 4, longAlign: 4,
+           ldSize: 12, ldAlign: 4, maxScalarAlign: 4, headSize: 8)
+  else:
+    raise newException(ValueError, "unknown target '" & name & "', expected one of " &
+      targetNames.join(", "))
+
+const pyObjectTypes* = toHashSet([
+  "object", "str", "bytes", "unicode", "bytearray", "dict", "list", "tuple",
+  "set", "frozenset", "type", "slice", "complex", "BaseException", "Exception",
+  "basestring", "memoryview", "array"])
+
+## Multi-word C base types, keyed by their normalized spelling.
+proc cScalar*(name: string, t: Target): tuple[size, align: int, ok: bool] =
+  template r(s: int): untyped = (s, min(s, t.maxScalarAlign), true)
+  case name
+  of "char", "signed char", "unsigned char", "_Bool", "bool": r(1)
+  of "short", "short int", "unsigned short", "unsigned short int",
+     "signed short", "signed short int": r(2)
+  of "int", "signed", "signed int", "unsigned", "unsigned int": r(4)
+  of "long", "long int", "unsigned long", "unsigned long int",
+     "signed long", "signed long int": (t.longSize, t.longAlign, true)
+  of "long long", "long long int", "unsigned long long",
+     "unsigned long long int", "signed long long", "signed long long int": r(8)
+  of "float": r(4)
+  of "double": r(8)
+  of "long double": (t.ldSize, t.ldAlign, true)
+  of "float complex": r(8)
+  of "double complex": r(16)
+  # Fixed-width and semantic integers.
+  of "int8_t", "uint8_t": r(1)
+  of "int16_t", "uint16_t", "char16_t": r(2)
+  of "int32_t", "uint32_t", "char32_t": r(4)
+  of "int64_t", "uint64_t": r(8)
+  of "size_t", "ssize_t", "Py_ssize_t", "ptrdiff_t", "intptr_t", "uintptr_t",
+     "Py_hash_t", "Py_uintptr_t", "uintmax_t", "intmax_t":
+    (t.ptrSize, t.ptrAlign, true)
+  of "Py_UCS4", "wchar_t": r(4)
+  of "Py_UCS2": r(2)
+  of "Py_UCS1": r(1)
+  of "bint": r(4)              # Cython lowers bint to int
+  of "void": (0, 1, false)     # only legal behind a pointer
+  else: (0, 0, false)
+
+## Structs whose layout is fixed by an ABI we can rely on, written as ordinary
+## declarations so that every target computes them itself instead of trusting a
+## number measured on one machine. A real definition in the sources being linted
+## takes precedence over these.
+const builtinDecls* = """
+cdef struct AVRational:
+    int num
+    int den
+
+cdef union AVChannelLayoutU:
+    uint64_t mask
+    void *map
+
+cdef struct AVChannelLayout:
+    int order
+    int nb_channels
+    AVChannelLayoutU u
+    void *opaque
+
+cdef struct AVIndexEntry:
+    int64_t pos
+    int64_t timestamp
+    int flags_and_size
+    int min_distance
+
+cdef struct AVSubtitle:
+    uint16_t format
+    uint32_t start_display_time
+    uint32_t end_display_time
+    unsigned int num_rects
+    void *rects
+    int64_t pts
+
+cdef struct PyObject:
+    Py_ssize_t ob_refcnt
+    void *ob_type
+
+cdef struct Py_buffer:
+    void *buf
+    void *obj
+    Py_ssize_t len
+    Py_ssize_t itemsize
+    int readonly
+    int ndim
+    char *format
+    Py_ssize_t *shape
+    Py_ssize_t *strides
+    Py_ssize_t *suboffsets
+    void *internal
+"""