mixer.c

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                         0,
                         Line);
                Ret = FALSE;
                break;
            }
        }
        else
        {
            DPRINT("Allocation of SND_MIXER_DEST structure for id %d failed!\n", i);
            Ret = FALSE;
            break;
        }
    }

    return Ret;
}

BOOL
SndMixerSelect(PSND_MIXER Mixer,
               UINT MixerId)
{
    if (MixerId >= Mixer->MixersCount)
    {
        return FALSE;
    }

    SndMixerClose(Mixer);

    if (mixerOpen(&Mixer->hmx,
                  MixerId,
                  (DWORD_PTR)Mixer->hWndNotification,
                  0,
                  CALLBACK_WINDOW | MIXER_OBJECTF_MIXER) == MMSYSERR_NOERROR ||
        mixerOpen(&Mixer->hmx,
                  MixerId,
                  (DWORD_PTR)Mixer->hWndNotification,
                  0,
                  CALLBACK_WINDOW) == MMSYSERR_NOERROR ||
        mixerOpen(&Mixer->hmx,
                  MixerId,
                  0,
                  0,
                  0) == MMSYSERR_NOERROR)
    {
        if (mixerGetDevCaps(MixerId,
                            &Mixer->Caps,
                            sizeof(Mixer->Caps)) == MMSYSERR_NOERROR)
        {
            BOOL Ret = FALSE;

            Mixer->MixerId = MixerId;

            ClearMixerCache(Mixer);

            Ret = SndMixerQueryDestinations(Mixer);

            if (!Ret)
            {
                ClearMixerCache(Mixer);
            }

            return Ret;
        }
        else
        {
            mixerClose(Mixer->hmx);
        }
    }

    Mixer->hmx = NULL;
    Mixer->MixerId = NO_MIXER_SELECTED;
    return FALSE;
}

UINT
SndMixerGetSelection(PSND_MIXER Mixer)
{
    return Mixer->MixerId;
}

INT
SndMixerGetProductName(PSND_MIXER Mixer,
                       LPTSTR lpBuffer,
                       UINT uSize)
{
    if (Mixer->hmx)
    {
        UINT lnsz = (UINT) lstrlen(Mixer->Caps.szPname);
        if(lnsz + 1 > uSize)
        {
            return lnsz + 1;
        }
        else
        {
            memcpy(lpBuffer, Mixer->Caps.szPname, lnsz * sizeof(TCHAR));
            lpBuffer[lnsz] = _T('\0');
            return lnsz;
        }
    }

    return -1;
}

INT
SndMixerGetLineName(PSND_MIXER Mixer,
                    DWORD LineID,
                    LPTSTR lpBuffer,
                    UINT uSize,
                    BOOL LongName)
{
    if (Mixer->hmx)
    {
        UINT lnsz;
        PSND_MIXER_DESTINATION Line;
        LPMIXERLINE lpl = NULL;

        for (Line = Mixer->Lines; Line != NULL; Line = Line->Next)
        {
            if (Line->Info.dwLineID == LineID)
            {
                lpl = &Line->Info;
                break;
            }
        }

        if (lpl != NULL)
        {
            lnsz = (UINT) lstrlen(LongName ? lpl->szName : lpl->szShortName);
            if(lnsz + 1 > uSize)
            {
                return lnsz + 1;
            }
            else
            {
                memcpy(lpBuffer, LongName ? lpl->szName : lpl->szShortName, lnsz * sizeof(TCHAR));
                lpBuffer[lnsz] = _T('\0');
                return lnsz;
            }
        }
    }

    return -1;
}

BOOL
SndMixerEnumProducts(PSND_MIXER Mixer,
                     PFNSNDMIXENUMPRODUCTS EnumProc,
                     PVOID Context)
{
    MIXERCAPS Caps;
    HMIXER hMixer;
    UINT i;
    BOOL Ret = TRUE;

    for (i = 0; i < Mixer->MixersCount; i++)
    {
        if (mixerOpen(&hMixer,
                      i,
                      0,
                      0,
                      0) == MMSYSERR_NOERROR)
        {
            if (mixerGetDevCaps(i,
                                &Caps,
                                sizeof(Caps)) == MMSYSERR_NOERROR)
            {
                if (!EnumProc(Mixer,
                              i,
                              Caps.szPname,
                              Context))
                {
                    mixerClose(hMixer);
                    Ret = FALSE;
                    break;
                }
            }
            else
            {
                DPRINT("Failed to get device capabilities for mixer id %d!\n", i);
            }
            mixerClose(hMixer);
        }
    }

    return Ret;
}

INT
SndMixerGetDestinationCount(PSND_MIXER Mixer)
{
    return (Mixer->hmx ? Mixer->Caps.cDestinations : -1);
}

BOOL
SndMixerEnumLines(PSND_MIXER Mixer,
                  PFNSNDMIXENUMLINES EnumProc,
                  PVOID Context)
{
    if (Mixer->hmx)
    {
        PSND_MIXER_DESTINATION Line;

        for (Line = Mixer->Lines; Line != NULL; Line = Line->Next)
        {
            if (!EnumProc(Mixer,
                          &Line->Info,
                          Line->DisplayControls,
                          Context))
            {
                return FALSE;
            }
        }

        return TRUE;
    }

    return FALSE;
}

BOOL
SndMixerEnumConnections(PSND_MIXER Mixer,
                        DWORD LineID,
                        PFNSNDMIXENUMCONNECTIONS EnumProc,
                        PVOID Context)
{
    if (Mixer->hmx)
    {
        PSND_MIXER_DESTINATION Line;

        for (Line = Mixer->Lines; Line != NULL; Line = Line->Next)
        {
            if (Line->Info.dwLineID == LineID)
            {
                PSND_MIXER_CONNECTION Connection;

                if (Line->DisplayControls != 0)
                {
                    if (!EnumProc(Mixer,
                                  LineID,
                                  &Line->Info,
                                  Context))
                    {
                        return FALSE;
                    }
                }

                for (Connection = Line->Connections; Connection != NULL; Connection = Connection->Next)
                {
                    if (!EnumProc(Mixer,
                                  LineID,
                                  &Connection->Info,
                                  Context))
                    {
                        return FALSE;
                    }
                }

                return TRUE;
            }
        }
    }

    return FALSE;
}

BOOL
SndMixerIsDisplayControl(PSND_MIXER Mixer,
                         LPMIXERCONTROL Control)
{
    if (Mixer->hmx && !(Control->fdwControl & MIXERCONTROL_CONTROLF_DISABLED))
    {
        switch (Control->dwControlType & MIXERCONTROL_CT_CLASS_MASK)
        {
            case MIXERCONTROL_CT_CLASS_FADER:
            case MIXERCONTROL_CT_CLASS_SWITCH:
                return TRUE;
        }
    }

    return FALSE;
}