cpi_stream_localfile.c

< VC++视频音频开发>> 这本书的源码

#include "stdafx.h"
#include "globals.h"
#include "CPI_Stream.h"

typedef struct _CPs_InStream_File
{
    HANDLE m_hFile;

} CPs_InStream_File;
//

void CPSLOCAL_Uninitialise(CPs_InStream* pStream);
BOOL CPSLOCAL_Read(CPs_InStream* pStream, void* pDestBuffer, const unsigned int iBytesToRead, unsigned int* piBytesRead);
void CPSLOCAL_Seek(CPs_InStream* pStream, const unsigned int iNewOffset);
unsigned int CPSLOCAL_GetLength(CPs_InStream* pStream);
BOOL CPSLOCAL_IsSeekable(CPs_InStream* pStream);
unsigned int CPSLOCAL_Tell(CPs_InStream* pStream);

CPs_InStream* CP_CreateInStream_LocalFile(const char* pcFlexiURL, HWND hWndOwner)
{
    HANDLE hFile;

    hFile = CreateFile(pcFlexiURL, GENERIC_READ,
                       FILE_SHARE_READ | FILE_SHARE_WRITE, 0,
                       OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN, 0);

    if(hFile == INVALID_HANDLE_VALUE)
        return NULL;

    {
        CPs_InStream* pNewStream = (CPs_InStream*)malloc(sizeof(CPs_InStream));
        CPs_InStream_File* pContext = (CPs_InStream_File*)malloc(sizeof(CPs_InStream_File));

        pNewStream->Uninitialise = CPSLOCAL_Uninitialise;
        pNewStream->Read = CPSLOCAL_Read;
        pNewStream->Seek = CPSLOCAL_Seek;
		pNewStream->Tell = CPSLOCAL_Tell;
        pNewStream->GetLength = CPSLOCAL_GetLength;
        pNewStream->IsSeekable = CPSLOCAL_IsSeekable;
        pNewStream->m_pModuleCookie = pContext;

        pContext->m_hFile = hFile;

        return pNewStream;
    }
}
//

void CPSLOCAL_Uninitialise(CPs_InStream* pStream)
{
    CPs_InStream_File* pContext = (CPs_InStream_File*)pStream->m_pModuleCookie;
    CP_CHECKOBJECT(pContext);

    CloseHandle(pContext->m_hFile);
    free(pContext);
    free(pStream);
}
//

BOOL CPSLOCAL_Read(CPs_InStream* pStream, void* pDestBuffer, const unsigned int iBytesToRead, unsigned int* piBytesRead)
{
    CPs_InStream_File* pContext = (CPs_InStream_File*)pStream->m_pModuleCookie;
    CP_CHECKOBJECT(pContext);

    return ReadFile(pContext->m_hFile, pDestBuffer, iBytesToRead, piBytesRead, 0);
}
//
void CPSLOCAL_Seek(CPs_InStream* pStream, const unsigned int iNewOffset)
{
    CPs_InStream_File* pContext = (CPs_InStream_File*)pStream->m_pModuleCookie;
    CP_CHECKOBJECT(pContext);

    SetFilePointer(pContext->m_hFile, iNewOffset, 0, FILE_BEGIN);
}
//
unsigned int CPSLOCAL_GetLength(CPs_InStream* pStream)
{
    CPs_InStream_File* pContext = (CPs_InStream_File*)pStream->m_pModuleCookie;
    CP_CHECKOBJECT(pContext);

    return GetFileSize(pContext->m_hFile, NULL);
}
//
BOOL CPSLOCAL_IsSeekable(CPs_InStream* pStream)
{
    return TRUE;
}
//
#define GetFilePointer(hFile) SetFilePointer(hFile, 0, NULL, FILE_CURRENT)

unsigned int CPSLOCAL_Tell(CPs_InStream* pStream)
{
    CPs_InStream_File* pContext = (CPs_InStream_File*)pStream->m_pModuleCookie;
    CP_CHECKOBJECT(pContext);

    return GetFilePointer(pContext->m_hFile);
}