Re: [PATCH 2/2] winealsa: implement GetPropValue and return device path (try 2)

[Andrew Eikum]

Looking pretty good. Couple notes below.

On Wed, Nov 19, 2014 at 02:35:39PM +0000, Mark Harmstone wrote:
> diff --git a/dlls/winealsa.drv/mmdevdrv.c b/dlls/winealsa.drv/mmdevdrv.c
> index 5ad72f9..c21fd0c 100644
> --- a/dlls/winealsa.drv/mmdevdrv.c
> +++ b/dlls/winealsa.drv/mmdevdrv.c
> @@ -3823,3 +3823,107 @@ HRESULT WINAPI AUDDRV_GetAudioSessionManager(IMMDevice *device,
>
> return S_OK;
>  }
> +
> +enum AudioDeviceConnectionType {
> +    AudioDeviceConnectionType_Unknown = 0,
> +    AudioDeviceConnectionType_PCI,
> +    AudioDeviceConnectionType_USB
> +};
> +
> +HRESULT WINAPI AUDDRV_GetPropValue(GUID *guid, const PROPERTYKEY *prop, PROPVARIANT *out)
> +{
> +    static const PROPERTYKEY devicepath_key = { /* undocumented? - {b3f8fa53-0004-438e-9003-51a46e139bfc},2 */
> +        {0xb3f8fa53, 0x0004, 0x438e, {0x90, 0x03, 0x51, 0xa4, 0x6e, 0x13, 0x9b, 0xfc}}, 2
> +    };
> +
> +    static const char dev_info[] = "/sys/class/sound/card%u/device/uevent";
> +

I'd prefer "const char *" and actually, is there any reason not to
just put this string straight in the sprintf?
> +    TRACE("%s, (%s,%u), %p\n", wine_dbgstr_guid(guid), wine_dbgstr_guid(&prop->fmtid), prop->pid, out);
> +
> +    if(IsEqualGUID(&prop->fmtid, &devicepath_key.fmtid) && prop->pid == devicepath_key.pid)
> +    {

I think you can use IsEqualPropertyKey here.
> +        char name[256], uevent[MAX_PATH];
> +        EDataFlow flow;
> +        FILE *fuevent;
> +        int card, device;
> +
> +        if(!get_alsa_name_by_guid(guid, name, sizeof(name), &flow))
> +        {
> +            WARN("Unknown interface %s\n", debugstr_guid(guid));
> +            return E_NOINTERFACE;
> +        }
> +
> +        /* only implemented for identifiable devices, i.e. not "default" */
> +        if(!sscanf(name, "plughw:%u,%u", &card, &device))
> +            return E_NOTIMPL;
> +
> +        sprintf(uevent, dev_info, card);
> +        fuevent = fopen(uevent, "r");
> +
> +        if(fuevent){
> +            enum AudioDeviceConnectionType connection = AudioDeviceConnectionType_Unknown;
> +            USHORT vendor_id = 0, product_id = 0;
> +            char *line = NULL;
> +
> +            while (!feof(fuevent)) {
> +                char *val;
> +                size_t val_len, len = 0;
> +
> +                getline(&line, &len, fuevent);
> +

We should probably break on failure here.
> +                if((val = strchr(line, '='))) {
> +                    val[0] = 0;
> +                    val++;
> +
> +                    val_len = strlen(val);
> +                    if (val_len > 0 && val[val_len - 1] == '\n') { val[val_len - 1] = 0; }
> +
> +                    if(!strcmp(line, "PCI_ID")){
> +                        connection = AudioDeviceConnectionType_PCI;
> +                        sscanf(val, "%hX:%hX", &vendor_id, &product_id);
> +                    }else if (!strcmp(line, "DEVTYPE") && !strcmp(val,"usb_interface"))
> +                        connection = AudioDeviceConnectionType_USB;
> +                    else if (!strcmp(line, "PRODUCT"))
> +                        sscanf(val, "%hx/%hx/", &vendor_id, &product_id);
> +                }
> +            }

Can we do anything sane on sscanf failure here? Maybe dump a WARN and
revert back to AudioDeviceConnectionType_Unknown. Is that preferable
to falling back on 0 for one or more of the IDs?

Andrew