MIDI播放音乐示例程序

///////////////////////////////////////////////////////////////////////////// // Copyright (C) 1998 by J�rg K�nig // All rights reserved // // This file is part of the completely free tetris clone "CGTetris". // // This is free software. // You may redistribute it by any means providing it is not sold for profit // without the authors written consent. // // No warrantee of any kind, expressed or implied, is included with this // software; use at your own risk, responsibility for damages (if any) to // anyone resulting from the use of this software rests entirely with the // user. // // Send bug reports, bug fixes, enhancements, requests, flames, etc., and // I'll try to keep a version up to date. I can be reached as follows: // J.Koenig@adg.de (company site) // Joerg.Koenig@rhein-neckar.de (private site) ///////////////////////////////////////////////////////////////////////////// // Midi.cpp // // The CMIDI class is based on a sample in the DirectX SDK (mstream) #include "stdafx.h" #include "Midi.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif #define MThd 0x6468544D // Start of file #define MTrk 0x6B72544D // Start of track #define BUFFER_TIME_LENGTH 60 // Amount to fill in milliseconds // These structures are stored in MIDI files; they need to be byte aligned. // #pragma pack(1) // Contents of MThd chunk. struct MIDIFILEHDR { WORD wFormat; // Format (hi-lo) WORD wTrackCount; // # tracks (hi-lo) WORD wTimeDivision; // Time division (hi-lo) }; #pragma pack() // End of need for byte-aligned structures // Macros for swapping hi/lo-endian data // #define WORDSWAP(w) (((w) >> 8) | \ (((w) << 8) & 0xFF00)) #define DWORDSWAP(dw) (((dw) >> 24) | \ (((dw) >> 8) & 0x0000FF00) | \ (((dw) << 8) & 0x00FF0000) | \ (((dw) << 24) & 0xFF000000)) static char gteBadRunStat[] = "Reference to missing running status."; static char gteRunStatMsgTrunc[]= "Running status message truncated"; static char gteChanMsgTrunc[] = "Channel message truncated"; static char gteSysExLenTrunc[] = "SysEx event truncated (length)"; static char gteSysExTrunc[] = "SysEx event truncated"; static char gteMetaNoClass[] = "Meta event truncated (no class byte)"; static char gteMetaLenTrunc[] = "Meta event truncated (length)"; static char gteMetaTrunc[] = "Meta event truncated"; static char gteNoMem[] = "Out of memory during malloc call"; ////////////////////////////////////////////////////////////////////// // CMIDI -- Construction/Destruction ////////////////////////////////////////////////////////////////////// CMIDI::CMIDI() : m_dwSoundSize(0) , m_pSoundData(0) , m_dwFormat(0) , m_dwTrackCount(0) , m_dwTimeDivision(0) , m_bPlaying(FALSE) , m_hStream(0) , m_dwProgressBytes(0) , m_bLooped(FALSE) , m_tkCurrentTime(0) , m_dwBufferTickLength(0) , m_dwCurrentTempo(0) , m_dwTempoMultiplier(100) , m_bInsertTempo(FALSE) , m_bBuffersPrepared(FALSE) , m_nCurrentBuffer(0) , m_uMIDIDeviceID(MIDI_MAPPER) , m_nEmptyBuffers(0) , m_bPaused(FALSE) , m_uCallbackStatus(0) , m_hBufferReturnEvent(0) , m_ptsTrack(0) , m_ptsFound(0) , m_dwStatus(0) , m_tkNext(0) , m_dwMallocBlocks(0) { m_hBufferReturnEvent = ::CreateEvent(0, FALSE, FALSE, TEXT("Wait For Buffer Return")); ASSERT(m_hBufferReturnEvent != 0); } CMIDI::~CMIDI() { Stop(FALSE); if(m_hBufferReturnEvent) ::CloseHandle(m_hBufferReturnEvent); } BOOL CMIDI::Create(UINT uResID, CWnd * pWndParent /* = NULL */) { return Create(MAKEINTRESOURCE(uResID), pWndParent); } BOOL CMIDI::Create(LPCTSTR pszResID, CWnd * pWndParent /* = NULL */) { ////////////////////////////////////////////////////////////////// // load resource HINSTANCE hApp = ::GetModuleHandle(0); ASSERT(hApp); HRSRC hResInfo = ::FindResource(hApp, pszResID, TEXT("MIDI")); if(hResInfo == 0) return FALSE; HGLOBAL hRes = ::LoadResource(hApp, hResInfo); if(hRes == 0) return FALSE; LPVOID pTheSound = ::LockResource(hRes); if(pTheSound == 0) return FALSE; DWORD dwTheSound = ::SizeofResource(hApp, hResInfo); return Create(pTheSound, dwTheSound, pWndParent); } BOOL CMIDI::Create(LPVOID pSoundData, DWORD dwSize, CWnd * pWndParent /* = NULL */) { if( m_pSoundData ) { // already created ASSERT(FALSE); return FALSE; } ASSERT(pSoundData != 0); ASSERT(dwSize > 0); register LPBYTE p = LPBYTE(pSoundData); // check header of MIDI if(*(DWORD*)p != MThd) { ASSERT(FALSE); return FALSE; } p += sizeof(DWORD); // check header size DWORD dwHeaderSize = DWORDSWAP(*(DWORD*)p); if( dwHeaderSize != sizeof(MIDIFILEHDR) ) { ASSERT(FALSE); return FALSE; } p += sizeof(DWORD); // get header MIDIFILEHDR hdr; ::CopyMemory(&hdr, p, dwHeaderSize); m_dwFormat = DWORD(WORDSWAP(hdr.wFormat)); m_dwTrackCount = DWORD(WORDSWAP(hdr.wTrackCount)); m_dwTimeDivision = DWORD(WORDSWAP(hdr.wTimeDivision)); p += dwHeaderSize; // create the array of tracks m_Tracks.resize(m_dwTrackCount); for(register DWORD i = 0; i < m_dwTrackCount; ++i) { // check header of track if(*(DWORD*)p != MTrk) { ASSERT(FALSE); return FALSE; } p += sizeof(DWORD); m_Tracks[i].dwTrackLength = DWORDSWAP(*(DWORD*)p); p += sizeof(DWORD); m_Tracks[i].pTrackStart = m_Tracks[i].pTrackCurrent = p; p += m_Tracks[i].dwTrackLength; // Handle bozo MIDI files which contain empty track chunks if( !m_Tracks[i].dwTrackLength ) { m_Tracks[i].fdwTrack |= ITS_F_ENDOFTRK; continue; } // We always preread the time from each track so the mixer code can // determine which track has the next event with a minimum of work if( !GetTrackVDWord( &m_Tracks[i], &m_Tracks[i].tkNextEventDue )) { TRACE0("Error in MIDI data\n"); ASSERT(FALSE); return FALSE; } } m_pSoundData = pSoundData; m_dwSoundSize = dwSize; m_pWndParent = pWndParent; // allocate volume channels and initialise them m_Volumes.resize(NUM_CHANNELS, VOLUME_INIT); if( ! StreamBufferSetup() ) { ASSERT(FALSE); return FALSE; } return TRUE; } BOOL CMIDI :: Play(BOOL bInfinite /* = FALSE */) { if( IsPaused() ) { Continue(); return TRUE; } // calling Play() while it is already playing will restart from scratch if( IsPlaying() ) Stop(); // Clear the status of our callback so it will handle // MOM_DONE callbacks once more m_uCallbackStatus = 0; if( !m_bLooped ) m_bInsertTempo = TRUE; MMRESULT mmResult; if( (mmResult = midiStreamRestart(m_hStream)) != MMSYSERR_NOERROR ) { MidiError(mmResult); return FALSE; } m_bPlaying = TRUE; m_bLooped = bInfinite; return m_bPlaying; } BOOL CMIDI :: Stop(BOOL bReOpen /*=TRUE*/) { MMRESULT mmrRetVal; if( IsPlaying() || (m_uCallbackStatus != STATUS_CALLBACKDEAD) ) { m_bPlaying = m_bPaused = FALSE; if( m_uCallbackStatus != STATUS_CALLBACKDEAD && m_uCallbackStatus != STATUS_WAITINGFOREND ) m_uCallbackStatus = STATUS_KILLCALLBACK; if( (mmrRetVal = midiStreamStop(m_hStream) ) != MMSYSERR_NOERROR ) { MidiError(mmrRetVal); return FALSE; } if( (mmrRetVal = midiOutReset((HMIDIOUT)m_hStream)) != MMSYSERR_NOERROR ) { MidiError(mmrRetVal); return FALSE; } // Wait for the callback thread to release this thread, which it will do by // calling SetEvent() once all buffers are returned to it if( WaitForSingleObject( m_hBufferReturnEvent, DEBUG_CALLBACK_TIMEOUT ) == WAIT_TIMEOUT ) { // Note, this is a risky move because the callback may be genuinely busy, but // when we're debugging, it's safer and faster than freezing the application, // which leaves the MIDI device locked up and forces a system reset... TRACE0("Timed out waiting for MI