`Wave_write` does not write `pad byte`

[sabonerune]

Bug report

Bug description:

import io
import wave

test_bytes = b"RIFF&\x00\x00\x00WAVEfmt \x10\x00\x00\x00\x01\x00\x01\x00\x80\xbb\x00\x00\x80\xbb\x00\x00\x01\x00\x08\x00data\x01\x00\x00\x00\x80\x00"

r = io.BytesIO(test_bytes)

with wave.open(r, mode="rb") as rw:
    nframes = rw.getnframes()
    sampwidth = rw.getsampwidth()
    nchannels = rw.getnchannels()
    framerate = rw.getframerate()
    frames = rw.readframes(-1)

assert nframes == 1
assert sampwidth == 1
assert nchannels == 1
assert frames == b"\x80"

w = io.BytesIO()

with wave.open(w, mode="wb") as ww:
    ww.setsampwidth(sampwidth)
    ww.setnchannels(nchannels)
    ww.setframerate(framerate)
    ww.writeframes(frames)

value = w.getvalue()

# b'RIFF%\x00\x00\x00WAVEfmt \x10\x00\x00\x00\x01\x00\x01\x00\x80\xbb\x00\x00\x80\xbb\x00\x00\x01\x00\x08\x00data\x01\x00\x00\x00\x80'
print(value)

# AssertionError
assert test_bytes == value
assert test_bytes[-1] == value[-1] == 0
assert (
    int.from_bytes(test_bytes[4:8], byteorder="little")
    == int.from_bytes(value[4:8], byteorder="little")
    == 38
)

The data written is missing the last pad byte\x00.
Along with this, the size of the RIFF chunk is also incorrect.

ref: https://www.tactilemedia.com/info/MCI_Control_Info.html

If the chunk size is an odd number of bytes, a pad byte with value zero is written after ckData.

CPython versions tested on:

3.12

Operating systems tested on:

Windows

Linked PRs

• gh-117716: Fix wave RIFF padding for data chunks #145237