Bug 1195061 - Correctly restore audio hardware mix format after attempting to use an alternative format. r=padenot

This commit is contained in:
Matthew Gregan 2015-08-18 10:59:14 +12:00
parent daa6ebd7d2
commit 63b1424f7e

View File

@ -918,9 +918,6 @@ handle_channel_layout(cubeb_stream * stm, WAVEFORMATEX ** mix_format, const cub
return;
}
/* Otherwise, the hardware supports more than two channels. */
WAVEFORMATEX hw_mixformat = **mix_format;
/* The docs say that GetMixFormat is always of type WAVEFORMATEXTENSIBLE [1],
* so the reinterpret_cast below should be safe. In practice, this is not
* true, and we just want to bail out and let the rest of the code find a good
@ -930,9 +927,13 @@ handle_channel_layout(cubeb_stream * stm, WAVEFORMATEX ** mix_format, const cub
return;
}
WAVEFORMATEXTENSIBLE * format_pcm = reinterpret_cast<WAVEFORMATEXTENSIBLE *>(*mix_format);
/* Stash a copy of the original mix format in case we need to restore it later. */
WAVEFORMATEXTENSIBLE hw_mix_format = *format_pcm;
/* The hardware is in surround mode, we want to only use front left and front
* right. Try that, and check if it works. */
WAVEFORMATEXTENSIBLE * format_pcm = reinterpret_cast<WAVEFORMATEXTENSIBLE *>((*mix_format));
switch (stream_params->channels) {
case 1: /* Mono */
format_pcm->dwChannelMask = KSAUDIO_SPEAKER_MONO;
@ -969,7 +970,7 @@ handle_channel_layout(cubeb_stream * stm, WAVEFORMATEX ** mix_format, const cub
/* Not supported, no suggestion. This should not happen, but it does in the
* field with some sound cards. We restore the mix format, and let the rest
* of the code figure out the right conversion path. */
**mix_format = hw_mixformat;
*reinterpret_cast<WAVEFORMATEXTENSIBLE *>(*mix_format) = hw_mix_format;
} else if (hr == S_OK) {
LOG("Requested format accepted by WASAPI.\n");
}