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2520 lines
87 KiB
2520 lines
87 KiB
//==========================================================================;
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//
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// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
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// KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
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// PURPOSE.
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//
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// Copyright (c) 1993-1999 Microsoft Corporation
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//
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//--------------------------------------------------------------------------;
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//
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// codec.c
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//
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// Description:
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// This file contains the DriverProc and other routines which respond
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// to ACM messages.
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//
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// Throughout this module, 'g711' refers to both the A-law and u-law
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// coding standards. When the context requires that these coding
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// standards be differentiated we use 'alaw' and 'mulaw' or a similar
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// variation.
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//
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//
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//==========================================================================;
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#include <windows.h>
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#include <windowsx.h>
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#include <mmsystem.h>
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#include <mmddk.h>
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#include <mmreg.h>
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#include <msacm.h>
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#include <msacmdrv.h>
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#include <memory.h>
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#include "codec.h"
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#include "g711.h"
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#include "debug.h"
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const UINT gauFormatTagIndexToTag[] =
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{
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WAVE_FORMAT_PCM,
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WAVE_FORMAT_ALAW,
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WAVE_FORMAT_MULAW
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};
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#define ACM_DRIVER_MAX_FORMAT_TAGS SIZEOF_ARRAY(gauFormatTagIndexToTag)
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#define ACM_DRIVER_MAX_FILTER_TAGS 0
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//
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// array of sample rates supported
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//
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//
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const UINT gauFormatIndexToSampleRate[] =
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{
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8000,
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11025,
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22050,
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44100
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};
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#define ACM_DRIVER_MAX_SAMPLE_RATES SIZEOF_ARRAY(gauFormatIndexToSampleRate)
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#define ACM_DRIVER_MAX_CHANNELS G711_MAX_CHANNELS
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//
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// bits per sample supported
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//
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//
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#define ACM_DRIVER_MAX_BITSPERSAMPLE_PCM 1 // only 16 bit
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#define ACM_DRIVER_MAX_BITSPERSAMPLE_G711 1 // only 8 bit
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//
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// number of formats we enumerate per channel is number of sample rates
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// times number of channels times number of types (bits per sample).
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//
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#define ACM_DRIVER_MAX_FORMATS_PCM (ACM_DRIVER_MAX_SAMPLE_RATES * \
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ACM_DRIVER_MAX_CHANNELS * \
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ACM_DRIVER_MAX_BITSPERSAMPLE_PCM)
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#define ACM_DRIVER_MAX_FORMATS_G711 (ACM_DRIVER_MAX_SAMPLE_RATES * \
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ACM_DRIVER_MAX_CHANNELS * \
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ACM_DRIVER_MAX_BITSPERSAMPLE_G711)
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//==========================================================================;
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//
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//
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//
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//
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//==========================================================================;
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//--------------------------------------------------------------------------;
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//
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// int LoadStringCodec
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//
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// Description:
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// This function should be used by all codecs to load resource strings
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// which will be passed back to the ACM. It works correctly for all
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// platforms, as follows:
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//
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// Win16: Compiled to LoadString to load ANSI strings.
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//
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// Win32: The 32-bit ACM always expects Unicode strings. Therefore,
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// when UNICODE is defined, this function is compiled to
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// LoadStringW to load a Unicode string. When UNICODE is
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// not defined, this function loads an ANSI string, converts
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// it to Unicode, and returns the Unicode string to the
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// codec.
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//
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// Note that you may use LoadString for other strings (strings which
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// will not be passed back to the ACM), because these strings will
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// always be consistent with the definition of UNICODE.
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//
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// Arguments:
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// Same as LoadString, except that it expects an LPSTR for Win16 and a
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// LPWSTR for Win32.
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//
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// Return (int):
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// Same as LoadString.
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//
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//--------------------------------------------------------------------------;
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#ifndef _WIN32
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#define LoadStringCodec LoadString
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#else
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#ifdef UNICODE
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#define LoadStringCodec LoadStringW
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#else
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int FNGLOBAL LoadStringCodec
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(
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HINSTANCE hinst,
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UINT uID,
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LPWSTR lpwstr,
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int cch)
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{
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LPSTR lpstr;
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int iReturn;
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lpstr = (LPSTR)GlobalAlloc(GPTR, cch);
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if (NULL == lpstr)
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{
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return 0;
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}
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iReturn = LoadStringA(hinst, uID, lpstr, cch);
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if (0 == iReturn)
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{
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if (0 != cch)
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{
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lpwstr[0] = '\0';
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}
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}
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else
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{
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MultiByteToWideChar( GetACP(), 0, lpstr, cch, lpwstr, cch );
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}
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GlobalFree((HGLOBAL)lpstr);
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return iReturn;
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}
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#endif // UNICODE
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#endif // _WIN32
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//==========================================================================;
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//
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//
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//
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//
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//==========================================================================;
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//--------------------------------------------------------------------------;
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//
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// BOOL pcmIsValidFormat
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//
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// Description:
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// This function verifies that a wave format header is a valid PCM
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// header that _this_ ACM driver can deal with.
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//
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// Arguments:
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// LPWAVEFORMATEX pwfx: Pointer to format header to verify.
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//
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// Return (BOOL):
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// The return value is non-zero if the format header looks valid. A
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// zero return means the header is not valid.
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//
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//--------------------------------------------------------------------------;
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BOOL FNLOCAL pcmIsValidFormat
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(
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LPWAVEFORMATEX pwfx
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)
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{
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if (NULL == pwfx)
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return (FALSE);
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if (WAVE_FORMAT_PCM != pwfx->wFormatTag)
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return (FALSE);
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//
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// verify nChannels member is within the allowed range
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//
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if ((pwfx->nChannels < 1) || (pwfx->nChannels > ACM_DRIVER_MAX_CHANNELS))
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return (FALSE);
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//
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// only allow the bits per sample that we can encode and decode with
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//
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if (16 != pwfx->wBitsPerSample)
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return (FALSE);
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//
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// now verify that the block alignment is correct..
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//
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if (PCM_BLOCKALIGNMENT((LPPCMWAVEFORMAT)pwfx) != pwfx->nBlockAlign)
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return (FALSE);
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//
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// finally, verify that avg bytes per second is correct
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//
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if (PCM_AVGBYTESPERSEC((LPPCMWAVEFORMAT)pwfx) != pwfx->nAvgBytesPerSec)
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return (FALSE);
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return (TRUE);
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} // pcmIsValidFormat()
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//--------------------------------------------------------------------------;
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//
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// BOOL g711IsValidFormat
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//
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// Description:
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// This function verifies that a wave format header is a valid
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// G711 format header that _this_ ACM driver can deal with.
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//
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// Arguments:
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// LPWAVEFORMATEX pwfx: Pointer to format header to verify.
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//
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// Return (BOOL):
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// The return value is non-zero if the format header looks valid. A
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// zero return means the header is not valid.
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//
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//--------------------------------------------------------------------------;
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BOOL FNLOCAL g711IsValidFormat
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(
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LPWAVEFORMATEX pwfx
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)
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{
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if (NULL == pwfx)
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return (FALSE);
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if ((WAVE_FORMAT_MULAW != pwfx->wFormatTag) &&
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(WAVE_FORMAT_ALAW != pwfx->wFormatTag))
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return (FALSE);
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//
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// check channels
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//
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if ((pwfx->nChannels < 1) || (pwfx->nChannels > ACM_DRIVER_MAX_CHANNELS))
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return (FALSE);
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//
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// now verify that the block alignment is correct..
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//
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#if 0
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if (G711_BLOCKALIGNMENT(pwfx) != (UINT)pwfx->nBlockAlign)
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return (FALSE);
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#else
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//
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// unfortunately there has been at least one company who didn't
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// understand what the block alignment was really for and authored
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// a bunch of files incorrectly. to allow those files to work, we
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// will just make sure that whole samples remain...
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//
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// this codec will only author G711 formats with correct block
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// alignments however.
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//
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if (0 != (pwfx->nBlockAlign % G711_BLOCKALIGNMENT(pwfx)))
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return (FALSE);
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#endif
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//
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// verify that avg bytes per second is correct
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//
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if (G711_AVGBYTESPERSEC(pwfx) != pwfx->nAvgBytesPerSec)
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return (FALSE);
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//
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// check wBitsPerSample
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//
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if (G711_BITS_PER_SAMPLE != pwfx->wBitsPerSample)
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return (FALSE);
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//
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// cbSize must be validated also..
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//
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if (G711_WFX_EXTRA_BYTES != pwfx->cbSize)
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return (FALSE);
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return (TRUE);
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} // g711IsValidFormat()
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//==========================================================================;
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//
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//
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//
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//
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//==========================================================================;
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//--------------------------------------------------------------------------;
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//
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// LRESULT acmdDriverOpen
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//
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// Description:
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// This function is used to handle the DRV_OPEN message for the ACM
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// driver. The driver is 'opened' for many reasons with the most common
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// being in preperation for conversion work. It is very important that
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// the driver be able to correctly handle multiple open driver
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// instances.
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//
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// Read the comments for this function carefully!
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//
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// Note that multiple _streams_ can (and will) be opened on a single
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// open _driver instance_. Do not store/create instance data that must
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// be unique for each stream in this function. See the acmdStreamOpen
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// function for information on conversion streams.
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//
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// Arguments:
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// HDRVR hdrvr: Driver handle that will be returned to caller of the
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// OpenDriver function. Normally, this will be the ACM--but this is
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// not guaranteed. For example, if an ACM driver is implemented within
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// a waveform driver, then the driver will be opened by both MMSYSTEM
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// and the ACM.
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//
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// LPACMDRVOPENDESC paod: Open description defining how the ACM driver
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// is being opened. This argument may be NULL--see the comments below
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// for more information.
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//
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// Return (LRESULT):
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// The return value is non-zero if the open is successful. A zero
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// return signifies that the driver cannot be opened.
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//
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//--------------------------------------------------------------------------;
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LRESULT FNLOCAL acmdDriverOpen
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(
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HDRVR hdrvr,
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LPACMDRVOPENDESC paod
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)
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{
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PDRIVERINSTANCE pdi;
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//
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// the [optional] open description that is passed to this driver can
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// be from multiple 'managers.' for example, AVI looks for installable
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// drivers that are tagged with 'vidc' and 'vcap'. we need to verify
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// that we are being opened as an Audio Compression Manager driver.
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//
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// if paod is NULL, then the driver is being opened for some purpose
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// other than converting (that is, there will be no stream open
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// requests for this instance of being opened). the most common case
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// of this is the Control Panel's Drivers option checking for config
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// support (DRV_[QUERY]CONFIGURE).
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//
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// we want to succeed this open, but be able to know that this
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// open instance is bogus for creating streams. for this purpose we
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// leave most of the members of our instance structure that we
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// allocate below as zero...
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//
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if (NULL != paod)
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{
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//
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// refuse to open if we are not being opened as an ACM driver.
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// note that we do NOT modify the value of paod->dwError in this
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// case.
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//
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if (ACMDRIVERDETAILS_FCCTYPE_AUDIOCODEC != paod->fccType)
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{
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return (0L);
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}
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}
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|
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//
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// we are being opened as an installable driver--we can allocate some
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// instance data to be returned in dwId argument of the DriverProc;
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// or simply return non-zero to succeed the open.
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//
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// this driver allocates a small instance structure. note that we
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// rely on allocating the memory as zero-initialized!
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//
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pdi = (PDRIVERINSTANCE)LocalAlloc(LPTR, sizeof(*pdi));
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if (NULL == pdi)
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{
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//
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// if this open attempt was as an ACM driver, then return the
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// reason we are failing in the open description structure..
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//
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if (NULL != paod)
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{
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paod->dwError = MMSYSERR_NOMEM;
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}
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|
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//
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// fail to open
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//
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return (0L);
|
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}
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|
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//
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// fill in our instance structure... note that this instance data
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// can be anything that the ACM driver wishes to maintain the
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// open driver instance. this data should not contain any information
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// that must be maintained per open stream since multiple streams
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// can be opened on a single driver instance.
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//
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// also note that we do _not_ check the version of the ACM opening
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// us (paod->dwVersion) to see if it is at least new enough to work
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// with this driver (for example, if this driver required Version 3.0
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// of the ACM and a Version 2.0 installation tried to open us). the
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// reason we do not fail is to allow the ACM to get the driver details
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// which contains the version of the ACM that is _required_ by this
|
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// driver. the ACM will examine that value (in padd->vdwACM) and
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// do the right thing for this driver... like not load it and inform
|
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// the user of the problem.
|
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//
|
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pdi->hdrvr = hdrvr;
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pdi->hinst = GetDriverModuleHandle(hdrvr); // Module handle.
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|
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if (NULL != paod)
|
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{
|
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pdi->fnDriverProc = NULL;
|
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pdi->fccType = paod->fccType;
|
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pdi->vdwACM = paod->dwVersion;
|
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pdi->fdwOpen = paod->dwFlags;
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|
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pdi->fdwConfig = 0L;
|
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|
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paod->dwError = MMSYSERR_NOERROR;
|
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}
|
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|
|
|
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//
|
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// non-zero return is success for DRV_OPEN
|
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//
|
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return ((LRESULT)(UINT_PTR)pdi);
|
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} // acmdDriverOpen()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdDriverClose
|
|
//
|
|
// Description:
|
|
// This function handles the DRV_CLOSE message for the ACM driver. The
|
|
// driver receives a DRV_CLOSE message for each succeeded DRV_OPEN
|
|
// message (see acmdDriverOpen). The driver will only receive a close
|
|
// message for _successful_ opens.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is non-zero if the open instance can be closed.
|
|
// A zero return signifies that the ACM driver instance could not be
|
|
// closed.
|
|
//
|
|
// NOTE! It is _strongly_ recommended that the driver never fail to
|
|
// close. Note that the ACM will never allow a driver instance to
|
|
// be closed if there are open streams. An ACM driver does not need
|
|
// to check for this case.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdDriverClose
|
|
(
|
|
PDRIVERINSTANCE pdi
|
|
)
|
|
{
|
|
//
|
|
// check to see if we allocated instance data. if we did not, then
|
|
// immediately succeed.
|
|
//
|
|
if (NULL != pdi)
|
|
{
|
|
//
|
|
// close down the driver instance. this driver simply needs
|
|
// to free the instance data structure... note that if this
|
|
// 'free' fails, then this ACM driver probably trashed its
|
|
// heap; assume we didn't do that.
|
|
//
|
|
LocalFree((HLOCAL)pdi);
|
|
}
|
|
|
|
|
|
//
|
|
// non-zero return is success for DRV_CLOSE
|
|
//
|
|
return (1L);
|
|
} // acmdDriverClose()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdDriverConfigure
|
|
//
|
|
// Description:
|
|
// This function is called to handle the DRV_[QUERY]CONFIGURE messages.
|
|
// These messages are for 'configuration' support of the driver.
|
|
// Normally this will be for 'hardware'--that is, a dialog should be
|
|
// displayed to configure ports, IRQ's, memory mappings, etc if it
|
|
// needs to. However, a software only ACM driver may also require
|
|
// configuration for 'what is real time' or other quality vs time
|
|
// issues.
|
|
//
|
|
// The most common way that these messages are generated under Win 3.1
|
|
// and NT Product 1 is from the Control Panel's Drivers option. Other
|
|
// sources may generate these messages in future versions of Windows.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// HWND hwnd: Handle to parent window to use when displaying the
|
|
// configuration dialog box. An ACM driver is _required_ to display a
|
|
// modal dialog box using this hwnd argument as the parent. This
|
|
// argument may be (HWND)-1 which tells the driver that it is only
|
|
// being queried for configuration support.
|
|
//
|
|
// LPDRVCONFIGINFO pdci: Pointer to optional DRVCONFIGINFO structure.
|
|
// If this argument is NULL, then the ACM driver should invent its own
|
|
// storage location.
|
|
//
|
|
// Return (LRESULT):
|
|
// If the driver is being 'queried' for configuration support (that is,
|
|
// hwnd == (HWND)-1), then non-zero should be returned specifying
|
|
// the driver does support a configuration dialog--or zero should be
|
|
// returned specifying that no configuration dialog is supported.
|
|
//
|
|
// If the driver is being called to display the configuration dialog
|
|
// (that is, hwnd != (HWND)-1), then one of the following values
|
|
// should be returned:
|
|
//
|
|
// DRVCNF_CANCEL (0x0000): specifies that the dialog was displayed
|
|
// and canceled by the user. this value should also be returned if
|
|
// no configuration information was modified.
|
|
//
|
|
// DRVCNF_OK (0x0001): specifies that the dialog was displayed and
|
|
// the user pressed OK. This value should be returned even if the
|
|
// user didn't change anything - otherwise, the driver may not
|
|
// install properly.
|
|
//
|
|
// DRVCNF_RESTART (0x0002): specifies that the dialog was displayed
|
|
// and some configuration information was changed that requires
|
|
// Windows to be restarted before the changes take affect. the driver
|
|
// should remain configured with current values until the driver
|
|
// has been 'rebooted'.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdDriverConfigure
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
HWND hwnd,
|
|
LPDRVCONFIGINFO pdci
|
|
)
|
|
{
|
|
//
|
|
// first check to see if we are only being queried for configuration
|
|
// support. if hwnd == (HWND)-1 then we are being queried and should
|
|
// return zero for 'not supported' and non-zero for 'supported'.
|
|
//
|
|
if ((HWND)-1 == hwnd)
|
|
{
|
|
//
|
|
// this ACM driver does NOT support a configuration dialog box, so
|
|
// return zero...
|
|
//
|
|
return (0L);
|
|
}
|
|
|
|
|
|
//
|
|
// we are being asked to bring up our configuration dialog. if this
|
|
// driver supports a configuration dialog box, then after the dialog
|
|
// is dismissed we must return one of the following values:
|
|
//
|
|
// DRVCNF_CANCEL (0x0000): specifies that the dialog was displayed
|
|
// and canceled by the user. this value should also be returned if
|
|
// no configuration information was modified.
|
|
//
|
|
// DRVCNF_OK (0x0001): specifies that the dialog was displayed and
|
|
// the user pressed OK. This value should be returned even if the
|
|
// user didn't change anything - otherwise, the driver may not
|
|
// install properly.
|
|
//
|
|
// DRVCNF_RESTART (0x0002): specifies that the dialog was displayed
|
|
// and some configuration information was changed that requires
|
|
// Windows to be restarted before the changes take affect. the driver
|
|
// should remain configured with current values until the driver
|
|
// has been 'rebooted'.
|
|
//
|
|
//
|
|
// return DRVCNF_CANCEL--this ACM driver does not support configuration
|
|
//
|
|
return (DRVCNF_CANCEL);
|
|
} // acmdDriverConfigure()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdDriverDetails
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_DRIVER_DETAILS message. The ACM
|
|
// driver is responsible for filling in the ACMDRIVERDETAILS structure
|
|
// with various information.
|
|
//
|
|
// NOTE! It is *VERY* important that you fill in your ACMDRIVERDETAILS
|
|
// structure correctly. The ACM and applications must be able to
|
|
// rely on this information.
|
|
//
|
|
// WARNING! The _reserved_ bits of any fields of the ACMDRIVERDETAILS
|
|
// structure are _exactly that_: RESERVED. Do NOT use any extra
|
|
// flag bits, etc. for custom information. The proper way to add
|
|
// custom capabilities to your ACM driver is this:
|
|
//
|
|
// o define a new message in the ACMDM_USER range.
|
|
//
|
|
// o an application that wishes to use one of these extra features
|
|
// should then:
|
|
//
|
|
// o open the driver with acmDriverOpen.
|
|
//
|
|
// o check for the proper wMid and wPid using acmDriverDetails.
|
|
//
|
|
// o send the 'user defined' message with acmDriverMessage
|
|
// to retrieve additional information, etc.
|
|
//
|
|
// o close the driver with acmDriverClose.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// LPACMDRIVERDETAILS padd: Pointer to ACMDRIVERDETAILS structure to
|
|
// fill in for the caller. This structure may be larger or smaller than
|
|
// the current definition of ACMDRIVERDETAILS--cbStruct specifies the
|
|
// valid size.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) for success. Non-zero
|
|
// signifies that the driver details could not be retrieved.
|
|
//
|
|
// NOTE THAT THIS FUNCTION SHOULD NEVER FAIL! There are two possible
|
|
// error conditions:
|
|
//
|
|
// o if padd is NULL or an invalid pointer.
|
|
//
|
|
// o if cbStruct is less than four; in this case, there is not enough
|
|
// room to return the number of bytes filled in.
|
|
//
|
|
// Because these two error conditions are easily defined, the ACM
|
|
// will catch these errors. The driver does NOT need to check for these
|
|
// conditions.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdDriverDetails
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
LPACMDRIVERDETAILS padd
|
|
)
|
|
{
|
|
ACMDRIVERDETAILS add;
|
|
DWORD cbStruct;
|
|
|
|
//
|
|
// it is easiest to fill in a temporary structure with valid info
|
|
// and then copy the requested number of bytes to the destination
|
|
// buffer.
|
|
//
|
|
cbStruct = min(padd->cbStruct, sizeof(ACMDRIVERDETAILS));
|
|
add.cbStruct = cbStruct;
|
|
|
|
|
|
//
|
|
// for the current implementation of an ACM driver, the fccType and
|
|
// fccComp members *MUST* always be ACMDRIVERDETAILS_FCCTYPE_AUDIOCODEC
|
|
// ('audc') and ACMDRIVERDETAILS_FCCCOMP_UNDEFINED (0) respectively.
|
|
//
|
|
add.fccType = ACMDRIVERDETAILS_FCCTYPE_AUDIOCODEC;
|
|
add.fccComp = ACMDRIVERDETAILS_FCCCOMP_UNDEFINED;
|
|
|
|
|
|
//
|
|
// the manufacturer id (wMid) and product id (wPid) must be filled
|
|
// in with your company's _registered_ identifier's. for more
|
|
// information on these identifier's and how to get them registered
|
|
// contact Microsoft and get the Multimedia Developer Registration Kit:
|
|
//
|
|
// Microsoft Corporation
|
|
// Multimedia Technology Group
|
|
// One Microsoft Way
|
|
// Redmond, WA 98052-6399
|
|
//
|
|
// Developer Services Phone: (800) 227-4679 x11771
|
|
//
|
|
// note that during the development phase or your ACM driver, you may
|
|
// use the reserved value of '0' for both wMid and wPid. however it
|
|
// is not acceptable to ship a driver with these values.
|
|
//
|
|
add.wMid = MM_MICROSOFT;
|
|
add.wPid = MM_MSFT_ACM_G711;
|
|
|
|
|
|
//
|
|
// the vdwACM and vdwDriver members contain version information for
|
|
// the driver.
|
|
//
|
|
// vdwACM: must contain the version of the *ACM* that the driver was
|
|
// _designed_ for. this is the _minimum_ version number of the ACM
|
|
// that the driver will work with. this value must be >= V2.00.000.
|
|
//
|
|
// vdwDriver: the version of this ACM driver.
|
|
//
|
|
// ACM driver versions are 32 bit numbers broken into three parts as
|
|
// follows (note these parts are displayed as decimal values):
|
|
//
|
|
// bits 24 - 31: 8 bit _major_ version number
|
|
// bits 16 - 23: 8 bit _minor_ version number
|
|
// bits 0 - 15: 16 bit build number
|
|
//
|
|
add.vdwACM = VERSION_MSACM;
|
|
add.vdwDriver = VERSION_ACM_DRIVER;
|
|
|
|
|
|
//
|
|
// the following flags are used to specify the type of conversion(s)
|
|
// that the ACM driver supports. note that a driver may support one or
|
|
// more of these flags in any combination.
|
|
//
|
|
// ACMDRIVERDETAILS_SUPPORTF_CODEC: this flag is set if the driver
|
|
// supports conversions from one format tag to another format tag. for
|
|
// example, if a converter compresses or decompresses WAVE_FORMAT_PCM
|
|
// and WAVE_FORMAT_IMA_ADPCM, then this bit should be set. this is
|
|
// true even if the data is not actually changed in size--for example
|
|
// a conversion from u-Law to A-Law will still set this bit because
|
|
// the format tags differ.
|
|
//
|
|
// ACMDRIVERDETAILS_SUPPORTF_CONVERTER: this flags is set if the
|
|
// driver supports conversions on the same format tag. as an example,
|
|
// the PCM converter that is built into the ACM sets this bit (and only
|
|
// this bit) because it converts only between PCM formats (bits, sample
|
|
// rate).
|
|
//
|
|
// ACMDRIVERDETAILS_SUPPORTF_FILTER: this flag is set if the driver
|
|
// supports transformations on a single format tag but does change
|
|
// the base characteristics of the format (bit depth, sample rate, etc
|
|
// will remain the same). for example, a driver that changed the
|
|
// 'volume' of PCM data or applied a low pass filter would set this bit.
|
|
//
|
|
add.fdwSupport = ACMDRIVERDETAILS_SUPPORTF_CODEC;
|
|
|
|
|
|
//
|
|
// the number of individual format tags this ACM driver supports. for
|
|
// example, if a driver uses the WAVE_FORMAT_IMA_ADPCM and
|
|
// WAVE_FORMAT_PCM format tags, then this value would be two. if the
|
|
// driver only supports filtering on WAVE_FORMAT_PCM, then this value
|
|
// would be one. if this driver supported WAVE_FORMAT_ALAW,
|
|
// WAVE_FORMAT_MULAW and WAVE_FORMAT_PCM, then this value would be
|
|
// three. etc, etc.
|
|
//
|
|
add.cFormatTags = ACM_DRIVER_MAX_FORMAT_TAGS;
|
|
|
|
//
|
|
// the number of individual filter tags this ACM driver supports. if
|
|
// a driver supports no filters (ACMDRIVERDETAILS_SUPPORTF_FILTER is
|
|
// NOT set in the fdwSupport member), then this value must be zero.
|
|
//
|
|
add.cFilterTags = ACM_DRIVER_MAX_FILTER_TAGS;
|
|
|
|
|
|
//
|
|
// the remaining members in the ACMDRIVERDETAILS structure are sometimes
|
|
// not needed. because of this we make a quick check to see if we
|
|
// should go through the effort of filling in these members.
|
|
//
|
|
if (FIELD_OFFSET(ACMDRIVERDETAILS, hicon) < cbStruct)
|
|
{
|
|
//
|
|
// fill in the hicon member will a handle to a custom icon for
|
|
// the ACM driver. this allows the driver to be represented by
|
|
// an application graphically (usually this will be a company
|
|
// logo or something). if a driver does not wish to have a custom
|
|
// icon displayed, then simply set this member to NULL and a
|
|
// generic icon will be displayed instead.
|
|
//
|
|
// See the MSFILTER sample for a codec which contains a custom icon.
|
|
//
|
|
add.hicon = NULL;
|
|
|
|
//
|
|
// the short name and long name are used to represent the driver
|
|
// in a unique description. the short name is intended for small
|
|
// display areas (for example, in a menu or combo box). the long
|
|
// name is intended for more descriptive displays (for example,
|
|
// in an 'about box').
|
|
//
|
|
// NOTE! an ACM driver should never place formatting characters
|
|
// of any sort in these strings (for example CR/LF's, etc). it
|
|
// is up to the application to format the text.
|
|
//
|
|
LoadStringCodec(pdi->hinst, IDS_ACM_DRIVER_SHORTNAME, add.szShortName, SIZEOFACMSTR(add.szShortName));
|
|
LoadStringCodec(pdi->hinst, IDS_ACM_DRIVER_LONGNAME, add.szLongName, SIZEOFACMSTR(add.szLongName));
|
|
|
|
//
|
|
// the last three members are intended for 'about box' information.
|
|
// these members are optional and may be zero length strings if
|
|
// the driver wishes.
|
|
//
|
|
// NOTE! an ACM driver should never place formatting characters
|
|
// of any sort in these strings (for example CR/LF's, etc). it
|
|
// is up to the application to format the text.
|
|
//
|
|
if (FIELD_OFFSET(ACMDRIVERDETAILS, szCopyright) < cbStruct)
|
|
{
|
|
LoadStringCodec(pdi->hinst, IDS_ACM_DRIVER_COPYRIGHT, add.szCopyright, SIZEOFACMSTR(add.szCopyright));
|
|
LoadStringCodec(pdi->hinst, IDS_ACM_DRIVER_LICENSING, add.szLicensing, SIZEOFACMSTR(add.szLicensing));
|
|
LoadStringCodec(pdi->hinst, IDS_ACM_DRIVER_FEATURES, add.szFeatures, SIZEOFACMSTR(add.szFeatures));
|
|
}
|
|
}
|
|
|
|
|
|
//
|
|
// now copy the correct number of bytes to the caller's buffer
|
|
//
|
|
_fmemcpy(padd, &add, (UINT)add.cbStruct);
|
|
|
|
|
|
//
|
|
// success!
|
|
//
|
|
return (MMSYSERR_NOERROR);
|
|
} // acmdDriverDetails()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdDriverAbout
|
|
//
|
|
// Description:
|
|
// This function is called to handle the ACMDM_DRIVER_ABOUT message.
|
|
// An ACM driver has the option of displaying its own 'about box' or
|
|
// letting the ACM (or calling application) display one for it. This
|
|
// message is normally sent by the Control Panel's Sound Mapper
|
|
// option.
|
|
//
|
|
// It is recommended that an ACM driver allow a default about box
|
|
// be displayed for it--there should be no reason to bloat the size
|
|
// of a driver to simply display copyright, etc information when that
|
|
// information is contained in the ACMDRIVERDETAILS structure.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// HWND hwnd: Handle to parent window to use when displaying the
|
|
// configuration dialog box. An ACM driver is _required_ to display a
|
|
// modal dialog box using this hwnd argument as the parent. This
|
|
// argument may be (HWND)-1 which tells the driver that it is only
|
|
// being queried for about box support.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is MMSYSERR_NOTSUPPORTED if the ACM driver does
|
|
// not support a custom dialog box. In this case, the ACM or calling
|
|
// application will display a generic about box using the information
|
|
// contained in the ACMDRIVERDETAILS structure returned by the
|
|
// ACMDM_DRIVER_DETAILS message.
|
|
//
|
|
// If the driver chooses to display its own dialog box, then after
|
|
// the dialog is dismissed by the user, MMSYSERR_NOERROR should be
|
|
// returned.
|
|
//
|
|
// If the hwnd argument is equal to (HWND)-1, then no dialog should
|
|
// be displayed (the driver is only being queried for support). The
|
|
// driver must still return MMSYSERR_NOERROR (supported) or
|
|
// MMSYSERR_NOTSUPPORTED (no custom about box supported).
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdDriverAbout
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
HWND hwnd
|
|
)
|
|
{
|
|
//
|
|
// first check to see if we are only being queried for custom about
|
|
// box support. if hwnd == (HWND)-1 then we are being queried and
|
|
// should return MMSYSERR_NOTSUPPORTED for 'not supported' and
|
|
// MMSYSERR_NOERROR for 'supported'.
|
|
//
|
|
if ((HWND)-1 == hwnd)
|
|
{
|
|
//
|
|
// this ACM driver does NOT support a custom about box, so
|
|
// return MMSYSERR_NOTSUPPORTED...
|
|
//
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
}
|
|
|
|
|
|
//
|
|
// this driver does not support a custom dialog, so tell the ACM or
|
|
// calling application to display one for us. note that this is the
|
|
// _recommended_ method for consistency and simplicity of ACM drivers.
|
|
// why write code when you don't have to?
|
|
//
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
} // acmdDriverAbout()
|
|
|
|
|
|
//==========================================================================;
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//==========================================================================;
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdFormatSuggest
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_FORMAT_SUGGEST message. The purpose
|
|
// of this function is to provide a way for the ACM, a wave mapper or
|
|
// an application to quickly get a destination format that this driver
|
|
// can convert the source format to. The 'suggested' format should
|
|
// be as close to a common format as possible. This message is normally
|
|
// sent in response to an acmFormatSuggest function call.
|
|
//
|
|
// Another way to think about this message is: what format would this
|
|
// driver like to convert the source format to?
|
|
//
|
|
// The caller may place restrictions on the destination format that
|
|
// should be suggested. The padfs->fdwSuggest member contains the
|
|
// restriction bits passed by the caller--see the description for
|
|
// the return value for more information.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// LPACMDRVFORMATSUGGEST padfs: Pointer to an ACMDRVFORMATSUGGEST
|
|
// structure that describes the source and destination (possibly with
|
|
// restrictions) for a conversion.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// The driver should return MMSYSERR_NOTSUPPORTED if one or more of
|
|
// the destination restriction bits is not supported. It is strongly
|
|
// recommended that the driver support at least the following suggestion
|
|
// restriction bits:
|
|
//
|
|
// ACM_FORMATSUGGESTF_WFORMATTAG: The destination format tag must be
|
|
// the same as the wFormatTag member in the destination format header.
|
|
//
|
|
// ACM_FORMATSUGGESTF_NCHANNELS: The destination channel count must be
|
|
// the same as the nChannels member in the destination format header.
|
|
//
|
|
// ACM_FORMATSUGGESTF_NSAMPLESPERSEC: The destination samples per
|
|
// second must be the same as the nSamplesPerSec member in the
|
|
// destination format header.
|
|
//
|
|
// ACM_FORMATSUGGESTF_WBITSPERSAMPLE: The destination bits per sample
|
|
// must be the same as the wBitsPerSample member in the destination
|
|
// format header.
|
|
//
|
|
// If no destintation format can be suggested, then the driver should
|
|
// return ACMERR_NOTPOSSIBLE.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdFormatSuggest
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
LPACMDRVFORMATSUGGEST padfs
|
|
)
|
|
{
|
|
#define ACMD_FORMAT_SUGGEST_SUPPORT (ACM_FORMATSUGGESTF_WFORMATTAG | \
|
|
ACM_FORMATSUGGESTF_NCHANNELS | \
|
|
ACM_FORMATSUGGESTF_NSAMPLESPERSEC |\
|
|
ACM_FORMATSUGGESTF_WBITSPERSAMPLE)
|
|
|
|
LPWAVEFORMATEX pwfxSrc;
|
|
LPWAVEFORMATEX pwfxDst;
|
|
DWORD fdwSuggest;
|
|
|
|
|
|
//
|
|
// grab the suggestion restriction bits and verify that we support
|
|
// the ones that are specified... an ACM driver must return the
|
|
// MMSYSERR_NOTSUPPORTED if the suggestion restriction bits specified
|
|
// are not supported.
|
|
//
|
|
fdwSuggest = (ACM_FORMATSUGGESTF_TYPEMASK & padfs->fdwSuggest);
|
|
|
|
if (~ACMD_FORMAT_SUGGEST_SUPPORT & fdwSuggest)
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
|
|
|
|
//
|
|
// get the source and destination formats in more convenient variables
|
|
//
|
|
pwfxSrc = padfs->pwfxSrc;
|
|
pwfxDst = padfs->pwfxDst;
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
switch (pwfxSrc->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
//
|
|
// strictly verify that the source format is acceptable for
|
|
// this driver
|
|
//
|
|
if (!pcmIsValidFormat(pwfxSrc))
|
|
break;
|
|
|
|
|
|
//
|
|
// if the destination format tag is restricted, verify that
|
|
// it is within our capabilities...
|
|
//
|
|
// this driver is able to encode to A-Law and u-Law
|
|
//
|
|
if (ACM_FORMATSUGGESTF_WFORMATTAG & fdwSuggest)
|
|
{
|
|
if ((WAVE_FORMAT_ALAW != pwfxDst->wFormatTag) &&
|
|
(WAVE_FORMAT_MULAW != pwfxDst->wFormatTag))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->wFormatTag = WAVE_FORMAT_ALAW;
|
|
}
|
|
|
|
|
|
//
|
|
// if the destination channel count is restricted, verify that
|
|
// it is within our capabilities...
|
|
//
|
|
// this driver is not able to change the number of channels
|
|
//
|
|
if (ACM_FORMATSUGGESTF_NCHANNELS & fdwSuggest)
|
|
{
|
|
if (pwfxSrc->nChannels != pwfxDst->nChannels)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->nChannels = pwfxSrc->nChannels;
|
|
}
|
|
|
|
|
|
//
|
|
// if the destination samples per second is restricted, verify
|
|
// that it is within our capabilities...
|
|
//
|
|
// this driver is not able to change the sample rate
|
|
//
|
|
if (ACM_FORMATSUGGESTF_NSAMPLESPERSEC & fdwSuggest)
|
|
{
|
|
if (pwfxSrc->nSamplesPerSec != pwfxDst->nSamplesPerSec)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->nSamplesPerSec = pwfxSrc->nSamplesPerSec;
|
|
}
|
|
|
|
|
|
//
|
|
// if the destination bits per sample is restricted, verify
|
|
// that it is within our capabilities...
|
|
//
|
|
// this driver is only able to encode to 8 bit
|
|
//
|
|
if (ACM_FORMATSUGGESTF_WBITSPERSAMPLE & fdwSuggest)
|
|
{
|
|
if (G711_BITS_PER_SAMPLE != pwfxDst->wBitsPerSample)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->wBitsPerSample = G711_BITS_PER_SAMPLE;
|
|
}
|
|
|
|
|
|
//
|
|
// at this point, we have filled in all fields except the
|
|
// following for our 'suggested' destination format:
|
|
//
|
|
// nAvgBytesPerSec
|
|
// nBlockAlign
|
|
// cbSize
|
|
//
|
|
pwfxDst->nBlockAlign = G711_BLOCKALIGNMENT(pwfxDst);
|
|
pwfxDst->nAvgBytesPerSec = G711_AVGBYTESPERSEC(pwfxDst);
|
|
pwfxDst->cbSize = G711_WFX_EXTRA_BYTES;
|
|
|
|
return (MMSYSERR_NOERROR);
|
|
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
case WAVE_FORMAT_MULAW:
|
|
//
|
|
// strictly verify that the source format is acceptable for
|
|
// this driver
|
|
//
|
|
if (!g711IsValidFormat(pwfxSrc))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
|
|
//
|
|
// if the destination format tag is restricted, verify that
|
|
// it is within our capabilities...
|
|
//
|
|
// this driver is able to decode to PCM from u-Law and A-Law
|
|
// as well as convert between u-Law and A-Law
|
|
//
|
|
if (ACM_FORMATSUGGESTF_WFORMATTAG & fdwSuggest)
|
|
{
|
|
switch (pwfxDst->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
break;
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
if (WAVE_FORMAT_MULAW != pwfxSrc->wFormatTag)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
break;
|
|
|
|
case WAVE_FORMAT_MULAW:
|
|
if (WAVE_FORMAT_ALAW != pwfxSrc->wFormatTag)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
|
|
if (WAVE_FORMAT_PCM == pwfxDst->wFormatTag)
|
|
{
|
|
//
|
|
// if the destination bits per sample is restricted,
|
|
// verify that it is within our capabilities...
|
|
//
|
|
// this driver is only able to decode to 16 bit
|
|
//
|
|
if (ACM_FORMATSUGGESTF_WBITSPERSAMPLE & fdwSuggest)
|
|
{
|
|
if (16 != pwfxDst->wBitsPerSample)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->wBitsPerSample = 16;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
//
|
|
// if the destination bits per sample is restricted,
|
|
// verify that it is within our capabilities...
|
|
//
|
|
// this driver is only able to convert between u-Law and
|
|
// A-Law at the same bit depth (8 bit)
|
|
//
|
|
if (ACM_FORMATSUGGESTF_WBITSPERSAMPLE & fdwSuggest)
|
|
{
|
|
if (G711_BITS_PER_SAMPLE != pwfxDst->wBitsPerSample)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->wBitsPerSample = G711_BITS_PER_SAMPLE;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (ACM_FORMATSUGGESTF_WBITSPERSAMPLE & fdwSuggest)
|
|
{
|
|
if (16 == pwfxDst->wBitsPerSample)
|
|
{
|
|
pwfxDst->wFormatTag = WAVE_FORMAT_PCM;
|
|
}
|
|
else if (8 == pwfxDst->wBitsPerSample)
|
|
{
|
|
if (WAVE_FORMAT_ALAW == pwfxSrc->wFormatTag)
|
|
{
|
|
pwfxDst->wFormatTag = WAVE_FORMAT_MULAW;
|
|
}
|
|
else if (WAVE_FORMAT_MULAW == pwfxSrc->wFormatTag)
|
|
{
|
|
pwfxDst->wFormatTag = WAVE_FORMAT_ALAW;
|
|
}
|
|
else
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->wFormatTag = WAVE_FORMAT_PCM;
|
|
pwfxDst->wBitsPerSample = 16;
|
|
}
|
|
}
|
|
|
|
|
|
//
|
|
// if the destination channel count is restricted, verify that
|
|
// it is within our capabilities...
|
|
//
|
|
// this driver is not able to change the number of channels
|
|
//
|
|
if (ACM_FORMATSUGGESTF_NCHANNELS & fdwSuggest)
|
|
{
|
|
if (pwfxSrc->nChannels != pwfxDst->nChannels)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->nChannels = pwfxSrc->nChannels;
|
|
}
|
|
|
|
|
|
//
|
|
// if the destination samples per second is restricted, verify
|
|
// that it is within our capabilities...
|
|
//
|
|
// this driver is not able to change the sample rate
|
|
//
|
|
if (ACM_FORMATSUGGESTF_NSAMPLESPERSEC & fdwSuggest)
|
|
{
|
|
if (pwfxSrc->nSamplesPerSec != pwfxDst->nSamplesPerSec)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
else
|
|
{
|
|
pwfxDst->nSamplesPerSec = pwfxSrc->nSamplesPerSec;
|
|
}
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
if (WAVE_FORMAT_PCM == pwfxDst->wFormatTag)
|
|
{
|
|
//
|
|
// at this point, we have filled in all fields except the
|
|
// following for our 'suggested' destination format:
|
|
//
|
|
// nAvgBytesPerSec
|
|
// nBlockAlign
|
|
// cbSize !!! not used for PCM !!!
|
|
//
|
|
pwfxDst->nBlockAlign = PCM_BLOCKALIGNMENT((LPPCMWAVEFORMAT)pwfxDst);
|
|
pwfxDst->nAvgBytesPerSec = PCM_AVGBYTESPERSEC((LPPCMWAVEFORMAT)pwfxDst);
|
|
|
|
// pwfxDst->cbSize = not used;
|
|
}
|
|
|
|
//
|
|
// the suggested destination format tag is not PCM
|
|
//
|
|
else
|
|
{
|
|
|
|
//
|
|
// at this point, we have filled in all fields except the
|
|
// following for our 'suggested' destination format:
|
|
//
|
|
// nAvgBytesPerSec
|
|
// nBlockAlign
|
|
// cbSize
|
|
//
|
|
pwfxDst->nBlockAlign = G711_BLOCKALIGNMENT(pwfxDst);
|
|
pwfxDst->nAvgBytesPerSec = G711_AVGBYTESPERSEC(pwfxDst);
|
|
pwfxDst->cbSize = G711_WFX_EXTRA_BYTES;
|
|
}
|
|
return (MMSYSERR_NOERROR);
|
|
}
|
|
|
|
|
|
//
|
|
// can't suggest anything because either the source format is foreign
|
|
// or the destination format has restrictions that this ACM driver
|
|
// cannot deal with.
|
|
//
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
} // acmdFormatSuggest()
|
|
|
|
|
|
//==========================================================================;
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//==========================================================================;
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdFormatTagDetails
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_FORMATTAG_DETAILS message. This
|
|
// message is normally sent in response to an acmFormatTagDetails or
|
|
// acmFormatTagEnum function call. The purpose of this function is
|
|
// to get details about a specific format tag supported by this ACM
|
|
// driver.
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// LPACMFORMATTAGDETAILS padft: Pointer to an ACMFORMATTAGDETAILS
|
|
// structure that describes what format tag to retrieve details for.
|
|
//
|
|
// DWORD fdwDetails: Flags defining what format tag to retrieve the
|
|
// details for.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// The driver should return MMSYSERR_NOTSUPPORTED if the query type
|
|
// specified in fdwDetails is not supported. An ACM driver must
|
|
// support at least the following query types:
|
|
//
|
|
// ACM_FORMATTAGDETAILSF_INDEX: Indicates that a format tag index
|
|
// was given in the dwFormatTagIndex member of the ACMFORMATTAGDETAILS
|
|
// structure. The format tag and details must be returned in the
|
|
// structure specified by padft. The index ranges from zero to one less
|
|
// than the cFormatTags member returned in the ACMDRIVERDETAILS
|
|
// structure for this driver.
|
|
//
|
|
// ACM_FORMATTAGDETAILSF_FORMATTAG: Indicates that a format tag
|
|
// was given in the dwFormatTag member of the ACMFORMATTAGDETAILS
|
|
// structure. The format tag details must be returned in the structure
|
|
// specified by padft.
|
|
//
|
|
// ACM_FORMATTAGDETAILSF_LARGESTSIZE: Indicates that the details
|
|
// on the format tag with the largest format size in bytes must be
|
|
// returned. The dwFormatTag member will either be WAVE_FORMAT_UNKNOWN
|
|
// or the format tag to find the largest size for.
|
|
//
|
|
// If the details for the specified format tag cannot be retrieved
|
|
// from this driver, then ACMERR_NOTPOSSIBLE should be returned.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdFormatTagDetails
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
LPACMFORMATTAGDETAILS padft,
|
|
DWORD fdwDetails
|
|
)
|
|
{
|
|
UINT uFormatTag;
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//
|
|
switch (ACM_FORMATTAGDETAILSF_QUERYMASK & fdwDetails)
|
|
{
|
|
case ACM_FORMATTAGDETAILSF_INDEX:
|
|
//
|
|
// if the index is too large, then they are asking for a
|
|
// non-existant format. return error.
|
|
//
|
|
if (ACM_DRIVER_MAX_FORMAT_TAGS <= padft->dwFormatTagIndex)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
uFormatTag = gauFormatTagIndexToTag[(UINT)padft->dwFormatTagIndex];
|
|
break;
|
|
|
|
|
|
case ACM_FORMATTAGDETAILSF_LARGESTSIZE:
|
|
switch (padft->dwFormatTag)
|
|
{
|
|
case WAVE_FORMAT_UNKNOWN:
|
|
case WAVE_FORMAT_ALAW:
|
|
uFormatTag = WAVE_FORMAT_ALAW;
|
|
break;
|
|
|
|
case WAVE_FORMAT_MULAW:
|
|
uFormatTag = WAVE_FORMAT_MULAW;
|
|
break;
|
|
|
|
case WAVE_FORMAT_PCM:
|
|
uFormatTag = WAVE_FORMAT_PCM;
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
break;
|
|
|
|
|
|
case ACM_FORMATTAGDETAILSF_FORMATTAG:
|
|
switch (padft->dwFormatTag)
|
|
{
|
|
case WAVE_FORMAT_ALAW:
|
|
uFormatTag = WAVE_FORMAT_ALAW;
|
|
break;
|
|
|
|
case WAVE_FORMAT_MULAW:
|
|
uFormatTag = WAVE_FORMAT_MULAW;
|
|
break;
|
|
|
|
case WAVE_FORMAT_PCM:
|
|
uFormatTag = WAVE_FORMAT_PCM;
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
break;
|
|
|
|
|
|
//
|
|
// if this ACM driver does not understand a query type, then
|
|
// return 'not supported'
|
|
//
|
|
default:
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
}
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
switch (uFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
padft->dwFormatTagIndex = 0;
|
|
padft->dwFormatTag = WAVE_FORMAT_PCM;
|
|
padft->cbFormatSize = sizeof(PCMWAVEFORMAT);
|
|
padft->fdwSupport = ACMDRIVERDETAILS_SUPPORTF_CODEC;
|
|
padft->cStandardFormats = ACM_DRIVER_MAX_FORMATS_PCM;
|
|
|
|
//
|
|
// the ACM is responsible for the PCM format tag name
|
|
//
|
|
padft->szFormatTag[0] = '\0';
|
|
break;
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
padft->dwFormatTagIndex = 1;
|
|
padft->dwFormatTag = WAVE_FORMAT_ALAW;
|
|
padft->cbFormatSize = sizeof(WAVEFORMATEX) +
|
|
G711_WFX_EXTRA_BYTES;
|
|
padft->fdwSupport = ACMDRIVERDETAILS_SUPPORTF_CODEC;
|
|
padft->cStandardFormats = ACM_DRIVER_MAX_FORMATS_G711;
|
|
|
|
LoadStringCodec(pdi->hinst,
|
|
IDS_ACM_DRIVER_TAG_NAME_ALAW,
|
|
padft->szFormatTag,
|
|
SIZEOFACMSTR(padft->szFormatTag));
|
|
break;
|
|
|
|
case WAVE_FORMAT_MULAW:
|
|
padft->dwFormatTagIndex = 2;
|
|
padft->dwFormatTag = WAVE_FORMAT_MULAW;
|
|
padft->cbFormatSize = sizeof(WAVEFORMATEX) +
|
|
G711_WFX_EXTRA_BYTES;
|
|
padft->fdwSupport = ACMDRIVERDETAILS_SUPPORTF_CODEC;
|
|
padft->cStandardFormats = ACM_DRIVER_MAX_FORMATS_G711;
|
|
|
|
LoadStringCodec(pdi->hinst,
|
|
IDS_ACM_DRIVER_TAG_NAME_MULAW,
|
|
padft->szFormatTag,
|
|
SIZEOFACMSTR(padft->szFormatTag));
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
|
|
//
|
|
// return only the requested info
|
|
//
|
|
// the ACM will guarantee that the ACMFORMATTAGDETAILS structure
|
|
// passed is at least large enough to hold the base information of
|
|
// the details structure
|
|
//
|
|
padft->cbStruct = min(padft->cbStruct, sizeof(*padft));
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
return (MMSYSERR_NOERROR);
|
|
} // acmdFormatTagDetails()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdFormatDetails
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_FORMAT_DETAILS message. This
|
|
// message is normally sent in response to an acmFormatDetails or
|
|
// acmFormatEnum function call. The purpose of this function is
|
|
// to get details about a specific format for a specified format tag
|
|
// supported by this ACM driver.
|
|
//
|
|
// Note that an ACM driver can return a zero length string for the
|
|
// format name if it wishes to have the ACM create a format string
|
|
// for it. This is strongly recommended to simplify internationalizing
|
|
// the driver--the ACM will automatically take care of that. The
|
|
// following formula is used to format a string by the ACM:
|
|
//
|
|
// <nSamplesPerSec> kHz, <bit depth> bit, [Mono | Stereo | nChannels]
|
|
//
|
|
// <bit depth> = <nAvgBytesPerSec> * 8 / nSamplesPerSec / nChannels;
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// LPACMFORMATDETAILS padf: Pointer to an ACMFORMATDETAILS structure
|
|
// that describes what format (for a specified format tag) to retrieve
|
|
// details for.
|
|
//
|
|
// DWORD fdwDetails: Flags defining what format for a specified format
|
|
// tag to retrieve the details for.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// The driver should return MMSYSERR_NOTSUPPORTED if the query type
|
|
// specified in fdwDetails is not supported. An ACM driver must
|
|
// support at least the following query types:
|
|
//
|
|
// ACM_FORMATDETAILSF_INDEX: Indicates that a format index for the
|
|
// format tag was given in the dwFormatIndex member of the
|
|
// ACMFORMATDETAILS structure. The format details must be returned in
|
|
// the structure specified by padf. The index ranges from zero to one
|
|
// less than the cStandardFormats member returned in the
|
|
// ACMFORMATTAGDETAILS structure for a format tag.
|
|
//
|
|
// ACM_FORMATDETAILSF_FORMAT: Indicates that a WAVEFORMATEX structure
|
|
// pointed to by pwfx of the ACMFORMATDETAILS structure was given and
|
|
// the remaining details should be returned. The dwFormatTag member
|
|
// of the ACMFORMATDETAILS will be initialized to the same format
|
|
// tag as the pwfx member specifies. This query type may be used to
|
|
// get a string description of an arbitrary format structure.
|
|
//
|
|
// If the details for the specified format cannot be retrieved
|
|
// from this driver, then ACMERR_NOTPOSSIBLE should be returned.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdFormatDetails
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
LPACMFORMATDETAILS padf,
|
|
DWORD fdwDetails
|
|
)
|
|
{
|
|
LPWAVEFORMATEX pwfx;
|
|
UINT uFormatIndex;
|
|
UINT u;
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//
|
|
switch (ACM_FORMATDETAILSF_QUERYMASK & fdwDetails)
|
|
{
|
|
//
|
|
// enumerate by index
|
|
//
|
|
// verify that the format tag is something we know about and
|
|
// return the details on the 'standard format' supported by
|
|
// this driver at the specified index...
|
|
//
|
|
case ACM_FORMATDETAILSF_INDEX:
|
|
//
|
|
// put some stuff in more accessible variables--note that we
|
|
// bring variable sizes down to a reasonable size for 16 bit
|
|
// code...
|
|
//
|
|
pwfx = padf->pwfx;
|
|
uFormatIndex = (UINT)padf->dwFormatIndex;
|
|
|
|
switch (padf->dwFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
if (ACM_DRIVER_MAX_FORMATS_PCM <= padf->dwFormatIndex)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
//
|
|
// now fill in the format structure
|
|
//
|
|
pwfx->wFormatTag = WAVE_FORMAT_PCM;
|
|
|
|
u = uFormatIndex / (ACM_DRIVER_MAX_BITSPERSAMPLE_PCM * ACM_DRIVER_MAX_CHANNELS);
|
|
pwfx->nSamplesPerSec = gauFormatIndexToSampleRate[u];
|
|
|
|
u = uFormatIndex % ACM_DRIVER_MAX_CHANNELS;
|
|
pwfx->nChannels = u + 1;
|
|
pwfx->wBitsPerSample = 16;
|
|
|
|
pwfx->nBlockAlign = PCM_BLOCKALIGNMENT((LPPCMWAVEFORMAT)pwfx);
|
|
pwfx->nAvgBytesPerSec = PCM_AVGBYTESPERSEC((LPPCMWAVEFORMAT)pwfx);
|
|
|
|
//
|
|
// note that the cbSize field is NOT valid for PCM
|
|
// formats
|
|
//
|
|
// pwfx->cbSize = 0;
|
|
break;
|
|
|
|
case WAVE_FORMAT_MULAW:
|
|
case WAVE_FORMAT_ALAW:
|
|
if (ACM_DRIVER_MAX_FORMATS_G711 <= padf->dwFormatIndex)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
pwfx->wFormatTag = LOWORD(padf->dwFormatTag);
|
|
|
|
u = uFormatIndex / (ACM_DRIVER_MAX_BITSPERSAMPLE_G711 * ACM_DRIVER_MAX_CHANNELS);
|
|
pwfx->nSamplesPerSec = gauFormatIndexToSampleRate[u];
|
|
|
|
u = uFormatIndex % ACM_DRIVER_MAX_CHANNELS;
|
|
pwfx->nChannels = u + 1;
|
|
pwfx->wBitsPerSample = G711_BITS_PER_SAMPLE;
|
|
|
|
pwfx->nBlockAlign = G711_BLOCKALIGNMENT(pwfx);
|
|
pwfx->nAvgBytesPerSec = G711_AVGBYTESPERSEC(pwfx);
|
|
pwfx->cbSize = G711_WFX_EXTRA_BYTES;
|
|
break;
|
|
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
//
|
|
// return details on specified format
|
|
//
|
|
// the caller normally uses this to verify that the format is
|
|
// supported and to retrieve a string description...
|
|
//
|
|
case ACM_FORMATDETAILSF_FORMAT:
|
|
pwfx = padf->pwfx;
|
|
|
|
switch (pwfx->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
if (!pcmIsValidFormat(pwfx))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
break;
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
case WAVE_FORMAT_MULAW:
|
|
if (!g711IsValidFormat(pwfx))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
break;
|
|
|
|
|
|
default:
|
|
//
|
|
// don't know how to do the query type passed--return 'not
|
|
// supported'.
|
|
//
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
}
|
|
|
|
|
|
//
|
|
// return the size of the valid information we are returning
|
|
//
|
|
// the ACM will guarantee that the ACMFORMATDETAILS structure
|
|
// passed is at least large enough to hold the base structure
|
|
//
|
|
// note that we let the ACM create the format string for us since
|
|
// we require no special formatting (and don't want to deal with
|
|
// internationalization issues, etc). simply set the string to
|
|
// a zero length.
|
|
//
|
|
padf->cbStruct = min(padf->cbStruct, sizeof(*padf));
|
|
padf->fdwSupport = ACMDRIVERDETAILS_SUPPORTF_CODEC;
|
|
padf->szFormat[0] = '\0';
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
return (MMSYSERR_NOERROR);
|
|
} // acmdFormatDetails()
|
|
|
|
|
|
//==========================================================================;
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//==========================================================================;
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdStreamOpen
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_STREAM_OPEN message. This message
|
|
// is sent to initiate a new conversion stream. This is usually caused
|
|
// by an application calling acmStreamOpen. If this function is
|
|
// successful, then one or more ACMDM_STREAM_CONVERT messages will be
|
|
// sent to convert individual buffers (user calls acmStreamConvert).
|
|
//
|
|
// Note that an ACM driver will not receive open requests for ASYNC
|
|
// or FILTER operations unless the ACMDRIVERDETAILS_SUPPORTF_ASYNC
|
|
// or ACMDRIVERDETAILS_SUPPORTF_FILTER flags are set in the
|
|
// ACMDRIVERDETAILS structure. There is no need for the driver to
|
|
// check for these requests unless it sets those support bits.
|
|
//
|
|
// If the ACM_STREAMOPENF_QUERY flag is set in the padsi->fdwOpen
|
|
// member, then no resources should be allocated. Just verify that
|
|
// the conversion request is possible by this driver and return the
|
|
// appropriate error (either ACMERR_NOTPOSSIBLE or MMSYSERR_NOERROR).
|
|
// The driver will NOT receive an ACMDM_STREAM_CLOSE for queries.
|
|
//
|
|
// If the ACM_STREAMOPENF_NONREALTIME bit is NOT set, then conversion
|
|
// must be done in 'real-time'. This is a tough one to describe
|
|
// exactly. If the driver may have trouble doing the conversion without
|
|
// breaking up the audio, then a configuration dialog might be used
|
|
// to allow the user to specify whether the real-time conversion
|
|
// request should be succeeded. DO NOT SUCCEED THE CALL UNLESS YOU
|
|
// ACTUALLY CAN DO REAL-TIME CONVERSIONS! There may be another driver
|
|
// installed that can--so if you succeed the call you are hindering
|
|
// the performance of the user's system!
|
|
//
|
|
// Arguments:
|
|
// PDRIVERINSTANCE pdi: Pointer to private ACM driver instance structure.
|
|
// This structure is [optionally] allocated during the DRV_OPEN message
|
|
// which is handled by the acmdDriverOpen function.
|
|
//
|
|
// LPACMDRVSTREAMINSTANCE padsi: Pointer to instance data for the
|
|
// conversion stream. This structure was allocated by the ACM and
|
|
// filled with the most common instance data needed for conversions.
|
|
// This structure will be passed back to all future stream messages
|
|
// if the open succeeds. The information in this structure will never
|
|
// change during the lifetime of the stream--so it is not necessary
|
|
// to re-verify the information referenced by this structure.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// A driver should return ACMERR_NOTPOSSIBLE if the conversion cannot
|
|
// be performed due to incompatible source and destination formats.
|
|
//
|
|
// A driver should return MMSYSERR_NOTSUPPORTED if the conversion
|
|
// cannot be performed in real-time and the request does not specify
|
|
// the ACM_STREAMOPENF_NONREALTIME flag.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdStreamOpen
|
|
(
|
|
PDRIVERINSTANCE pdi,
|
|
LPACMDRVSTREAMINSTANCE padsi
|
|
)
|
|
{
|
|
LPWAVEFORMATEX pwfxSrc;
|
|
LPWAVEFORMATEX pwfxDst;
|
|
BOOL fRealTime;
|
|
STREAMCONVERTPROC fnConvert;
|
|
PSTREAMINSTANCE psi;
|
|
|
|
|
|
//
|
|
//
|
|
//
|
|
pwfxSrc = padsi->pwfxSrc;
|
|
pwfxDst = padsi->pwfxDst;
|
|
|
|
fRealTime = (0 == (padsi->fdwOpen & ACM_STREAMOPENF_NONREALTIME));
|
|
|
|
|
|
//
|
|
// the most important condition to check before doing anything else
|
|
// is that this ACM driver can actually perform the conversion we are
|
|
// being opened for. this check should fail as quickly as possible
|
|
// if the conversion is not possible by this driver.
|
|
//
|
|
// it is VERY important to fail quickly so the ACM can attempt to
|
|
// find a driver that is suitable for the conversion. also note that
|
|
// the ACM may call this driver several times with slightly different
|
|
// format specifications before giving up.
|
|
//
|
|
// this driver first verifies that the source and destination formats
|
|
// are acceptable...
|
|
//
|
|
switch (pwfxSrc->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
if (!pcmIsValidFormat(pwfxSrc))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
if (!g711IsValidFormat(pwfxDst))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
//
|
|
//
|
|
//
|
|
if (WAVE_FORMAT_ALAW == pwfxDst->wFormatTag)
|
|
fnConvert = PcmToAlaw;
|
|
else
|
|
fnConvert = PcmToUlaw;
|
|
break;
|
|
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
case WAVE_FORMAT_MULAW:
|
|
if (!g711IsValidFormat(pwfxSrc))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
if (WAVE_FORMAT_PCM == pwfxDst->wFormatTag)
|
|
{
|
|
if (!pcmIsValidFormat(pwfxDst))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
//
|
|
//
|
|
//
|
|
if (WAVE_FORMAT_ALAW == pwfxSrc->wFormatTag)
|
|
fnConvert = AlawToPcm;
|
|
else
|
|
fnConvert = UlawToPcm;
|
|
}
|
|
else
|
|
{
|
|
if (!g711IsValidFormat(pwfxDst))
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
//
|
|
// we are not a converter for equivelant format tags
|
|
//
|
|
if (pwfxSrc->wFormatTag == pwfxDst->wFormatTag)
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
|
|
//
|
|
//
|
|
//
|
|
if (WAVE_FORMAT_ALAW == pwfxSrc->wFormatTag)
|
|
fnConvert = AlawToUlaw;
|
|
else
|
|
fnConvert = UlawToAlaw;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
|
|
//
|
|
// for this driver, we must also verify that the nChannels and
|
|
// nSamplesPerSec members are the same between the source and
|
|
// destination formats.
|
|
//
|
|
if (pwfxSrc->nChannels != pwfxDst->nChannels)
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
|
|
if (pwfxSrc->nSamplesPerSec != pwfxDst->nSamplesPerSec)
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
|
|
|
|
//
|
|
// we have determined that the conversion requested is possible by
|
|
// this driver. now check if we are just being queried for support.
|
|
// if this is just a query, then do NOT allocate any instance data
|
|
// or create tables, etc. just succeed the call.
|
|
//
|
|
if (0 != (ACM_STREAMOPENF_QUERY & padsi->fdwOpen))
|
|
{
|
|
return (MMSYSERR_NOERROR);
|
|
}
|
|
|
|
|
|
//
|
|
// we have decided that this driver can handle the conversion stream.
|
|
// so we want to do _AS MUCH WORK AS POSSIBLE_ right now to prepare
|
|
// for converting data. any resource allocation, table building, etc
|
|
// that can be dealt with at this time should be done.
|
|
//
|
|
// THIS IS VERY IMPORTANT! all ACMDM_STREAM_CONVERT messages need to
|
|
// be handled as quickly as possible.
|
|
//
|
|
// this driver allocates a small instance structure for each stream
|
|
//
|
|
//
|
|
psi = (PSTREAMINSTANCE)LocalAlloc(LPTR, sizeof(*psi));
|
|
if (NULL == psi)
|
|
{
|
|
return (MMSYSERR_NOMEM);
|
|
}
|
|
|
|
|
|
//
|
|
// fill out our instance structure
|
|
//
|
|
// this driver stores a pointer to the conversion function that will
|
|
// be used for each conversion on this stream. we also store a
|
|
// copy of the _current_ configuration of the driver instance we
|
|
// are opened on. this must not change during the life of the stream
|
|
// instance.
|
|
//
|
|
// this is also very important! if the user is able to configure how
|
|
// the driver performs conversions, the changes should only affect
|
|
// future open streams. all current open streams should behave as
|
|
// they were configured during the open.
|
|
//
|
|
psi->fnConvert = fnConvert;
|
|
psi->fdwConfig = pdi->fdwConfig;
|
|
|
|
|
|
//
|
|
// fill in our instance data--this will be passed back to all stream
|
|
// messages in the ACMDRVSTREAMINSTANCE structure. it is entirely
|
|
// up to the driver what gets stored (and maintained) in the
|
|
// fdwDriver and dwDriver members.
|
|
//
|
|
padsi->fdwDriver = 0L;
|
|
padsi->dwDriver = (DWORD_PTR)psi;
|
|
|
|
return (MMSYSERR_NOERROR);
|
|
} // acmdStreamOpen()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdStreamClose
|
|
//
|
|
// Description:
|
|
// This function is called to handle the ACMDM_STREAM_CLOSE message.
|
|
// This message is sent when a conversion stream is no longer being
|
|
// used (the stream is being closed; usually by an application
|
|
// calling acmStreamClose). The ACM driver should clean up any resources
|
|
// that were allocated for the stream.
|
|
//
|
|
// Arguments:
|
|
// LPACMDRVSTREAMINSTANCE padsi: Pointer to instance data for the
|
|
// conversion stream. This structure was allocated by the ACM and
|
|
// filled with the most common instance data needed for conversions.
|
|
// The information in this structure is exactly the same as it was
|
|
// during the ACMDM_STREAM_OPEN message--so it is not necessary
|
|
// to re-verify the information referenced by this structure.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// NOTE! It is _strongly_ recommended that a driver not fail to close
|
|
// a conversion stream.
|
|
//
|
|
// An asyncronous conversion stream may fail with ACMERR_BUSY if there
|
|
// are pending buffers. An application may call acmStreamReset to
|
|
// force all pending buffers to be posted.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdStreamClose
|
|
(
|
|
LPACMDRVSTREAMINSTANCE padsi
|
|
)
|
|
{
|
|
PSTREAMINSTANCE psi;
|
|
|
|
//
|
|
// the driver should clean up all privately allocated resources that
|
|
// were created for maintaining the stream instance. if no resources
|
|
// were allocated, then simply succeed.
|
|
//
|
|
// in the case of this driver, we need to free the stream instance
|
|
// structure that we allocated during acmdStreamOpen.
|
|
//
|
|
psi = (PSTREAMINSTANCE)padsi->dwDriver;
|
|
if (NULL != psi)
|
|
{
|
|
//
|
|
// free the stream instance structure
|
|
//
|
|
LocalFree((HLOCAL)psi);
|
|
}
|
|
|
|
return (MMSYSERR_NOERROR);
|
|
} // acmdStreamClose()
|
|
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT acmdStreamSize
|
|
//
|
|
// Description:
|
|
// This function handles the ACMDM_STREAM_SIZE message. The purpose
|
|
// of this function is to provide the _largest size in bytes_ that
|
|
// the source or destination buffer needs to be given the input and
|
|
// output formats and the size in bytes of the source or destination
|
|
// data buffer.
|
|
//
|
|
// In other words: how big does my destination buffer need to be to
|
|
// hold the converted data? (ACM_STREAMSIZEF_SOURCE)
|
|
//
|
|
// Or: how big can my source buffer be given the destination buffer?
|
|
// (ACM_STREAMSIZEF_DESTINATION)
|
|
//
|
|
// Arguments:
|
|
// LPACMDRVSTREAMINSTANCE padsi: Pointer to instance data for the
|
|
// conversion stream. This structure was allocated by the ACM and
|
|
// filled with the most common instance data needed for conversions.
|
|
// The information in this structure is exactly the same as it was
|
|
// during the ACMDM_STREAM_OPEN message--so it is not necessary
|
|
// to re-verify the information referenced by this structure.
|
|
//
|
|
// LPACMDRVSTREAMSIZE padss: Specifies a pointer to the ACMDRVSTREAMSIZE
|
|
// structure that defines the conversion stream size query attributes.
|
|
//
|
|
// Return (LRESULT):
|
|
// The return value is zero (MMSYSERR_NOERROR) if this function
|
|
// succeeds with no errors. The return value is a non-zero error code
|
|
// if the function fails.
|
|
//
|
|
// An ACM driver should return MMSYSERR_NOTSUPPORTED if a query type
|
|
// is requested that the driver does not understand. Note that a driver
|
|
// must support both the ACM_STREAMSIZEF_DESTINATION and
|
|
// ACM_STREAMSIZEF_SOURCE queries.
|
|
//
|
|
// If the conversion would be 'out of range' given the input arguments,
|
|
// then ACMERR_NOTPOSSIBLE should be returned.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
LRESULT FNLOCAL acmdStreamSize
|
|
(
|
|
LPACMDRVSTREAMINSTANCE padsi,
|
|
LPACMDRVSTREAMSIZE padss
|
|
)
|
|
{
|
|
PSTREAMINSTANCE psi;
|
|
LPWAVEFORMATEX pwfxSrc;
|
|
LPWAVEFORMATEX pwfxDst;
|
|
DWORD cb;
|
|
|
|
pwfxSrc = padsi->pwfxSrc;
|
|
pwfxDst = padsi->pwfxDst;
|
|
|
|
psi = (PSTREAMINSTANCE)padsi->dwDriver;
|
|
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//
|
|
switch (ACM_STREAMSIZEF_QUERYMASK & padss->fdwSize)
|
|
{
|
|
//
|
|
// how many destination bytes are needed to hold the source data
|
|
// of padss->cbSrcLength bytes
|
|
//
|
|
// always round UP (since G711 can be computed exactly, don't
|
|
// round. it is simply a 2:1 compression ratio--and we drop partial
|
|
// samples)
|
|
//
|
|
case ACM_STREAMSIZEF_SOURCE:
|
|
cb = padss->cbSrcLength;
|
|
|
|
switch (pwfxSrc->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
cb = PCM_BYTESTOSAMPLES((LPPCMWAVEFORMAT)pwfxSrc, cb);
|
|
cb = PCM_SAMPLESTOBYTES((LPPCMWAVEFORMAT)pwfxSrc, cb);
|
|
|
|
if (0 == cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
cb = (cb / 2);
|
|
break;
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
case WAVE_FORMAT_MULAW:
|
|
cb = G711_BYTESTOSAMPLES(pwfxSrc, cb);
|
|
cb = G711_SAMPLESTOBYTES(pwfxSrc, cb);
|
|
|
|
if (0 == cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
if (WAVE_FORMAT_PCM == pwfxDst->wFormatTag)
|
|
{
|
|
// Make sure we won't overflow padss->cbDstLength
|
|
if ((0xFFFFFFFFL / 2) < cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
cb = (cb * 2);
|
|
}
|
|
break;
|
|
}
|
|
|
|
padss->cbDstLength = cb;
|
|
return (MMSYSERR_NOERROR);
|
|
|
|
|
|
//
|
|
// how many source bytes can be encoded into a
|
|
// destination buffer of padss->cbDstLength bytes
|
|
//
|
|
// always round DOWN (drop partial samples)
|
|
//
|
|
case ACM_STREAMSIZEF_DESTINATION:
|
|
cb = padss->cbDstLength;
|
|
|
|
switch (pwfxDst->wFormatTag)
|
|
{
|
|
case WAVE_FORMAT_PCM:
|
|
cb = PCM_BYTESTOSAMPLES((LPPCMWAVEFORMAT)pwfxDst, cb);
|
|
cb = PCM_SAMPLESTOBYTES((LPPCMWAVEFORMAT)pwfxDst, cb);
|
|
|
|
cb = (cb / 2);
|
|
|
|
if (0 == cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
break;
|
|
|
|
case WAVE_FORMAT_ALAW:
|
|
case WAVE_FORMAT_MULAW:
|
|
cb = G711_BYTESTOSAMPLES(pwfxDst, cb);
|
|
cb = G711_SAMPLESTOBYTES(pwfxDst, cb);
|
|
|
|
if (0 == cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
|
|
if (WAVE_FORMAT_PCM == pwfxSrc->wFormatTag)
|
|
{
|
|
// Make sure we won't overflow padss->cbDstLength
|
|
if ((0xFFFFFFFFL / 2) < cb)
|
|
{
|
|
return (ACMERR_NOTPOSSIBLE);
|
|
}
|
|
cb = (cb * 2);
|
|
}
|
|
break;
|
|
}
|
|
|
|
padss->cbSrcLength = cb;
|
|
return (MMSYSERR_NOERROR);
|
|
}
|
|
|
|
//
|
|
// if the query type is not understood by this driver, then we need
|
|
// to return MMSYSERR_NOTSUPPORTED.
|
|
//
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
} // acmdStreamSize()
|
|
|
|
|
|
//==========================================================================;
|
|
//
|
|
//
|
|
//
|
|
//
|
|
//==========================================================================;
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//
|
|
// LRESULT DriverProc
|
|
//
|
|
// Description:
|
|
//
|
|
//
|
|
// Arguments:
|
|
// DWORD dwId: For most messages, dwId is the DWORD value that
|
|
// the driver returns in response to a DRV_OPEN message. Each time
|
|
// the driver is opened, through the OpenDriver API, the driver
|
|
// receives a DRV_OPEN message and can return an arbitrary, non-zero
|
|
// value. The installable driver interface saves this value and returns
|
|
// a unique driver handle to the application. Whenever the application
|
|
// sends a message to the driver using the driver handle, the interface
|
|
// routes the message to this entry point and passes the corresponding
|
|
// dwId. This mechanism allows the driver to use the same or different
|
|
// identifiers for multiple opens but ensures that driver handles are
|
|
// unique at the application interface layer.
|
|
//
|
|
// The following messages are not related to a particular open instance
|
|
// of the driver. For these messages, the dwId will always be zero.
|
|
//
|
|
// DRV_LOAD, DRV_FREE, DRV_ENABLE, DRV_DISABLE, DRV_OPEN
|
|
//
|
|
// HDRVR hdrvr: This is the handle returned to the application
|
|
// by the driver interface.
|
|
//
|
|
// UINT uMsg: The requested action to be performed. Message
|
|
// values below DRV_RESERVED are used for globally defined messages.
|
|
// Message values from DRV_RESERVED to DRV_USER are used for defined
|
|
// driver protocols. Messages above DRV_USER are used for driver
|
|
// specific messages.
|
|
//
|
|
// LPARAM lParam1: Data for this message. Defined separately for
|
|
// each message.
|
|
//
|
|
// LPARAM lParam2: Data for this message. Defined separately for
|
|
// each message.
|
|
//
|
|
// Return (LRESULT):
|
|
// Defined separately for each message.
|
|
//
|
|
//--------------------------------------------------------------------------;
|
|
|
|
EXTERN_C LRESULT FNEXPORT DriverProc
|
|
(
|
|
DWORD_PTR dwId,
|
|
HDRVR hdrvr,
|
|
UINT uMsg,
|
|
LPARAM lParam1,
|
|
LPARAM lParam2
|
|
)
|
|
{
|
|
LRESULT lr;
|
|
PDRIVERINSTANCE pdi;
|
|
|
|
//
|
|
// make pdi either NULL or a valid instance pointer. note that dwId
|
|
// is 0 for several of the DRV_* messages (ie DRV_LOAD, DRV_OPEN...)
|
|
// see acmdDriverOpen for information on what dwId is for other
|
|
// messages (instance data).
|
|
//
|
|
pdi = (PDRIVERINSTANCE)dwId;
|
|
|
|
switch (uMsg)
|
|
{
|
|
//
|
|
// lParam1: Unused.
|
|
//
|
|
// lParam2: Unused.
|
|
//
|
|
case DRV_LOAD:
|
|
#ifdef _WIN32
|
|
DbgInitialize(TRUE);
|
|
#endif
|
|
return(1L);
|
|
|
|
//
|
|
// lParam1: Unused.
|
|
//
|
|
// lParam2: Unused.
|
|
//
|
|
case DRV_FREE:
|
|
return (1L);
|
|
|
|
|
|
//
|
|
// lParam1: Not used. Ignore this argument.
|
|
//
|
|
// lParam2: Pointer to ACMDRVOPENDESC (or NULL).
|
|
//
|
|
case DRV_OPEN:
|
|
lr = acmdDriverOpen(hdrvr, (LPACMDRVOPENDESC)lParam2);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Unused.
|
|
//
|
|
// lParam2: Unused.
|
|
//
|
|
case DRV_CLOSE:
|
|
lr = acmdDriverClose(pdi);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Unused.
|
|
//
|
|
// lParam2: Unused.
|
|
//
|
|
case DRV_INSTALL:
|
|
return ((LRESULT)DRVCNF_RESTART);
|
|
|
|
//
|
|
// lParam1: Unused.
|
|
//
|
|
// lParam2: Unused.
|
|
//
|
|
case DRV_REMOVE:
|
|
return ((LRESULT)DRVCNF_RESTART);
|
|
|
|
|
|
|
|
//
|
|
// lParam1: Not used.
|
|
//
|
|
// lParam2: Not used.
|
|
//
|
|
case DRV_QUERYCONFIGURE:
|
|
//
|
|
// set up lParam1 and lParam2 to values that can be used by
|
|
// acmdDriverConfigure to know that it is being 'queried'
|
|
// for configuration support.
|
|
//
|
|
lParam1 = -1L;
|
|
lParam2 = 0L;
|
|
|
|
//--fall through--//
|
|
|
|
//
|
|
// lParam1: Handle to parent window for the configuration dialog
|
|
// box.
|
|
//
|
|
// lParam2: Optional pointer to DRVCONFIGINFO structure.
|
|
//
|
|
case DRV_CONFIGURE:
|
|
lr = acmdDriverConfigure(pdi, (HWND)lParam1, (LPDRVCONFIGINFO)lParam2);
|
|
return (lr);
|
|
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRIVERDETAILS structure.
|
|
//
|
|
// lParam2: Size in bytes of ACMDRIVERDETAILS stucture passed.
|
|
//
|
|
case ACMDM_DRIVER_DETAILS:
|
|
lr = acmdDriverDetails(pdi, (LPACMDRIVERDETAILS)lParam1);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Handle to parent window to use if displaying your own
|
|
// about box.
|
|
//
|
|
// lParam2: Not used.
|
|
//
|
|
case ACMDM_DRIVER_ABOUT:
|
|
lr = acmdDriverAbout(pdi, (HWND)lParam1);
|
|
return (lr);
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//--------------------------------------------------------------------------;
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRVFORMATSUGGEST structure.
|
|
//
|
|
// lParam2: Not used.
|
|
//
|
|
case ACMDM_FORMAT_SUGGEST:
|
|
lr = acmdFormatSuggest(pdi, (LPACMDRVFORMATSUGGEST)lParam1);
|
|
return (lr);
|
|
|
|
|
|
//
|
|
// lParam1: Pointer to FORMATTAGDETAILS structure.
|
|
//
|
|
// lParam2: fdwDetails
|
|
//
|
|
case ACMDM_FORMATTAG_DETAILS:
|
|
lr = acmdFormatTagDetails(pdi, (LPACMFORMATTAGDETAILS)lParam1, (DWORD)lParam2);
|
|
return (lr);
|
|
|
|
|
|
//
|
|
// lParam1: Pointer to FORMATDETAILS structure.
|
|
//
|
|
// lParam2: fdwDetails
|
|
//
|
|
case ACMDM_FORMAT_DETAILS:
|
|
lr = acmdFormatDetails(pdi, (LPACMFORMATDETAILS)lParam1, (DWORD)lParam2);
|
|
return (lr);
|
|
|
|
//--------------------------------------------------------------------------;
|
|
//--------------------------------------------------------------------------;
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRVSTREAMINSTANCE structure.
|
|
//
|
|
// lParam2: Not used.
|
|
//
|
|
case ACMDM_STREAM_OPEN:
|
|
lr = acmdStreamOpen(pdi, (LPACMDRVSTREAMINSTANCE)lParam1);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRVSTREAMINSTANCE structure.
|
|
//
|
|
// lParam2: Not Used.
|
|
//
|
|
case ACMDM_STREAM_CLOSE:
|
|
lr = acmdStreamClose((LPACMDRVSTREAMINSTANCE)lParam1);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRVSTREAMINSTANCE structure.
|
|
//
|
|
// lParam2: Pointer to ACMDRVSTREAMSIZE structure.
|
|
//
|
|
case ACMDM_STREAM_SIZE:
|
|
lr = acmdStreamSize((LPACMDRVSTREAMINSTANCE)lParam1, (LPACMDRVSTREAMSIZE)lParam2);
|
|
return (lr);
|
|
|
|
//
|
|
// lParam1: Pointer to ACMDRVSTREAMINSTANCE structure.
|
|
//
|
|
// lParam2: Pointer to ACMDRVSTREAMHEADER structure.
|
|
//
|
|
case ACMDM_STREAM_CONVERT:
|
|
{
|
|
PSTREAMINSTANCE psi;
|
|
LPACMDRVSTREAMINSTANCE padsi;
|
|
LPACMDRVSTREAMHEADER padsh;
|
|
|
|
//
|
|
// our stream instance data is a pointer to the conversion
|
|
// procedure needed to convert the pwfxSrc data to pwfxDst.
|
|
// the correct procedure to use was decided in acmdStreamOpen
|
|
//
|
|
padsi = (LPACMDRVSTREAMINSTANCE)lParam1;
|
|
padsh = (LPACMDRVSTREAMHEADER)lParam2;
|
|
|
|
psi = (PSTREAMINSTANCE)padsi->dwDriver;
|
|
|
|
lr = psi->fnConvert(padsi, padsh);
|
|
return (lr);
|
|
}
|
|
}
|
|
|
|
//
|
|
// if we are executing the following code, then this ACM driver does not
|
|
// handle the message that was sent. there are two ranges of messages
|
|
// we need to deal with:
|
|
//
|
|
// o ACM specific driver messages: if an ACM driver does not answer a
|
|
// message sent in the ACM driver message range, then it must
|
|
// return MMSYSERR_NOTSUPPORTED. this applies to the 'user'
|
|
// range as well (for consistency).
|
|
//
|
|
// o other installable driver messages: if an ACM driver does not
|
|
// answer a message that is NOT in the ACM driver message range,
|
|
// then it must call DefDriverProc and return that result.
|
|
// the exception to this is ACM driver procedures installed as
|
|
// ACM_DRIVERADDF_FUNCTION through acmDriverAdd. in this case,
|
|
// the driver procedure should conform to the ACMDRIVERPROC
|
|
// prototype and also return zero instead of calling DefDriverProc.
|
|
//
|
|
if (uMsg >= ACMDM_USER)
|
|
return (MMSYSERR_NOTSUPPORTED);
|
|
else
|
|
return (DefDriverProc(dwId, hdrvr, uMsg, lParam1, lParam2));
|
|
} // DriverProc()
|