libmng_chunk_io.c

Linux下的基于X11的图形开发环境。

    pData->bHasJHDR         = MNG_FALSE;
    pData->bHasJSEP         = MNG_FALSE;
    pData->bHasJDAA         = MNG_FALSE;
    pData->bHasJDAT         = MNG_FALSE;
#endif
    pData->bHasPLTE         = MNG_FALSE;
    pData->bHasTRNS         = MNG_FALSE;
    pData->bHasGAMA         = MNG_FALSE;
    pData->bHasCHRM         = MNG_FALSE;
    pData->bHasSRGB         = MNG_FALSE;
    pData->bHasICCP         = MNG_FALSE;
    pData->bHasBKGD         = MNG_FALSE;
    pData->bHasIDAT         = MNG_FALSE;
#ifdef MNG_SUPPORT_DISPLAY
  }
#endif  

#ifdef MNG_STORE_CHUNKS
  if (pData->bStorechunks)
  {                                    /* initialize storage */
    mng_retcode iRetcode = ((mng_chunk_headerp)pHeader)->fCreate (pData, pHeader, ppChunk);

    if (iRetcode)                      /* on error bail out */
      return iRetcode;
  }
#endif /* MNG_STORE_CHUNKS */

#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_READ_IEND, MNG_LC_END)
#endif

  return MNG_NOERROR;                  /* done */
}

/* ************************************************************************** */

READ_CHUNK (read_trns)
{
#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_READ_TRNS, MNG_LC_START)
#endif
                                       /* sequence checks */
  if ((!pData->bHasMHDR) && (!pData->bHasIHDR) &&
      (!pData->bHasBASI) && (!pData->bHasDHDR)    )
    MNG_ERROR (pData, MNG_SEQUENCEERROR)

#ifdef MNG_INCLUDE_JNG
  if ((pData->bHasIDAT) || (pData->bHasJHDR))
#else
  if (pData->bHasIDAT)
#endif  
    MNG_ERROR (pData, MNG_SEQUENCEERROR)
                                       /* multiple tRNS only inside BASI */
  if ((pData->bHasTRNS) && (!pData->bHasBASI))
    MNG_ERROR (pData, MNG_MULTIPLEERROR)

  if (iRawlen > 256)                   /* it just can't be bigger than that! */
    MNG_ERROR (pData, MNG_INVALIDLENGTH)

  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
  {                                    /* not allowed with full alpha-channel */
    if ((pData->iColortype == 4) || (pData->iColortype == 6))
      MNG_ERROR (pData, MNG_CHUNKNOTALLOWED)

    if (iRawlen != 0)                  /* filled ? */
    {                                  /* length checks */
      if ((pData->iColortype == 0) && (iRawlen != 2))
        MNG_ERROR (pData, MNG_INVALIDLENGTH)

      if ((pData->iColortype == 2) && (iRawlen != 6))
        MNG_ERROR (pData, MNG_INVALIDLENGTH)

#ifdef MNG_SUPPORT_DISPLAY
      if (pData->iColortype == 3)
      {
        mng_imagep     pImage = (mng_imagep)pData->pCurrentobj;
        mng_imagedatap pBuf;

        if (!pImage)                   /* no object then check obj 0 */
          pImage = (mng_imagep)pData->pObjzero;

        pBuf = pImage->pImgbuf;        /* address object buffer */

        if ((iRawlen == 0) || (iRawlen > pBuf->iPLTEcount))
          MNG_ERROR (pData, MNG_INVALIDLENGTH)
      }
#endif
    }
    else                               /* if empty there must be global stuff! */
    {
      if (!pData->bHasglobalTRNS)
        MNG_ERROR (pData, MNG_CANNOTBEEMPTY)
    }
  }

  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
    pData->bHasTRNS = MNG_TRUE;        /* indicate tRNS available */
  else
    pData->bHasglobalTRNS = MNG_TRUE;

#ifdef MNG_SUPPORT_DISPLAY
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
  {
    mng_imagep     pImage;
    mng_imagedatap pBuf;
    mng_uint8p     pRawdata2;
    mng_uint32     iRawlen2;

    if (pData->bHasDHDR)               /* processing delta-image ? */
    {                                  /* store in object 0 !!! */
      pImage = (mng_imagep)pData->pObjzero;
      pBuf   = pImage->pImgbuf;        /* address object buffer */

      switch (pData->iColortype)       /* store fields for future reference */
      {
        case 0: {                      /* gray */
                  pBuf->iTRNSgray  = mng_get_uint16 (pRawdata);
                  pBuf->iTRNSred   = 0;
                  pBuf->iTRNSgreen = 0;
                  pBuf->iTRNSblue  = 0;
                  pBuf->iTRNScount = 0;
                  break;
                }
        case 2: {                      /* rgb */
                  pBuf->iTRNSgray  = 0;
                  pBuf->iTRNSred   = mng_get_uint16 (pRawdata);
                  pBuf->iTRNSgreen = mng_get_uint16 (pRawdata+2);
                  pBuf->iTRNSblue  = mng_get_uint16 (pRawdata+4);
                  pBuf->iTRNScount = 0;
                  break;
                }
        case 3: {                      /* indexed */
                  pBuf->iTRNSgray  = 0;
                  pBuf->iTRNSred   = 0;
                  pBuf->iTRNSgreen = 0;
                  pBuf->iTRNSblue  = 0;
                  pBuf->iTRNScount = iRawlen;
                  MNG_COPY (pBuf->aTRNSentries, pRawdata, iRawlen)
                  break;
                }
      }

      pBuf->bHasTRNS = MNG_TRUE;       /* tell it it's got a tRNS now */
    }
    else
    {                                  /* address current object */
      pImage = (mng_imagep)pData->pCurrentobj;

      if (!pImage)                     /* no object then dump it in obj 0 */
        pImage = (mng_imagep)pData->pObjzero;

      pBuf = pImage->pImgbuf;          /* address object buffer */
      pBuf->bHasTRNS = MNG_TRUE;       /* and tell it it's got a tRNS now */

      if (iRawlen == 0)                /* if empty, inherit from global */
      {
        iRawlen2  = pData->iGlobalTRNSrawlen;
        pRawdata2 = (mng_ptr)(pData->aGlobalTRNSrawdata);
                                         /* global length oke ? */
        if ((pData->iColortype == 0) && (iRawlen2 != 2))
          MNG_ERROR (pData, MNG_GLOBALLENGTHERR)

        if ((pData->iColortype == 2) && (iRawlen2 != 6))
          MNG_ERROR (pData, MNG_GLOBALLENGTHERR)

        if ((pData->iColortype == 3) && ((iRawlen2 == 0) || (iRawlen2 > pBuf->iPLTEcount)))
          MNG_ERROR (pData, MNG_GLOBALLENGTHERR)
      }
      else
      {
        iRawlen2  = iRawlen;
        pRawdata2 = pRawdata;
      }

      switch (pData->iColortype)        /* store fields for future reference */
      {
        case 0: {                      /* gray */
                  pBuf->iTRNSgray  = mng_get_uint16 (pRawdata2);
                  pBuf->iTRNSred   = 0;
                  pBuf->iTRNSgreen = 0;
                  pBuf->iTRNSblue  = 0;
                  pBuf->iTRNScount = 0;
                  break;
                }
        case 2: {                      /* rgb */
                  pBuf->iTRNSgray  = 0;
                  pBuf->iTRNSred   = mng_get_uint16 (pRawdata2);
                  pBuf->iTRNSgreen = mng_get_uint16 (pRawdata2+2);
                  pBuf->iTRNSblue  = mng_get_uint16 (pRawdata2+4);
                  pBuf->iTRNScount = 0;
                  break;
                }
        case 3: {                      /* indexed */
                  pBuf->iTRNSgray  = 0;
                  pBuf->iTRNSred   = 0;
                  pBuf->iTRNSgreen = 0;
                  pBuf->iTRNSblue  = 0;
                  pBuf->iTRNScount = iRawlen2;
                  MNG_COPY (pBuf->aTRNSentries, pRawdata2, iRawlen2)
                  break;
                }
      }
    }  
  }
  else                                 /* store as global */
  {
    pData->iGlobalTRNSrawlen = iRawlen;
    MNG_COPY (pData->aGlobalTRNSrawdata, pRawdata, iRawlen)

    {                                  /* create an animation object */
      mng_retcode iRetcode = create_ani_trns (pData, pData->iGlobalTRNSrawlen,
                                              pData->aGlobalTRNSrawdata);

      if (iRetcode)                    /* on error bail out */
        return iRetcode;
    }
  }
#endif /* MNG_SUPPORT_DISPLAY */

#ifdef MNG_STORE_CHUNKS
  if (pData->bStorechunks)
  {                                    /* initialize storage */
    mng_retcode iRetcode = ((mng_chunk_headerp)pHeader)->fCreate (pData, pHeader, ppChunk);

    if (iRetcode)                      /* on error bail out */
      return iRetcode;

    if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
    {                                  /* not global! */
      ((mng_trnsp)*ppChunk)->bGlobal  = MNG_FALSE;
      ((mng_trnsp)*ppChunk)->iType    = pData->iColortype;

      if (iRawlen == 0)                /* if empty, indicate so */
        ((mng_trnsp)*ppChunk)->bEmpty = MNG_TRUE;
      else
      {
        ((mng_trnsp)*ppChunk)->bEmpty = MNG_FALSE;

        switch (pData->iColortype)     /* store fields */
        {
          case 0: {                    /* gray */
                    ((mng_trnsp)*ppChunk)->iGray  = mng_get_uint16 (pRawdata);
                    break;
                  }
          case 2: {                    /* rgb */
                    ((mng_trnsp)*ppChunk)->iRed   = mng_get_uint16 (pRawdata);
                    ((mng_trnsp)*ppChunk)->iGreen = mng_get_uint16 (pRawdata+2);
                    ((mng_trnsp)*ppChunk)->iBlue  = mng_get_uint16 (pRawdata+4);
                    break;
                  }
          case 3: {                    /* indexed */
                    ((mng_trnsp)*ppChunk)->iCount = iRawlen;
                    MNG_COPY (((mng_trnsp)*ppChunk)->aEntries, pRawdata, iRawlen)
                    break;
                  }
        }
      }
    }
    else                               /* it's global! */
    {
      ((mng_trnsp)*ppChunk)->bEmpty  = (mng_bool)(iRawlen == 0);
      ((mng_trnsp)*ppChunk)->bGlobal = MNG_TRUE;
      ((mng_trnsp)*ppChunk)->iType   = 0;
      ((mng_trnsp)*ppChunk)->iRawlen = iRawlen;

      MNG_COPY (((mng_trnsp)*ppChunk)->aRawdata, pRawdata, iRawlen)
    }
  }
#endif /* MNG_STORE_CHUNKS */

#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_READ_TRNS, MNG_LC_END)
#endif

  return MNG_NOERROR;                  /* done */
}

/* ************************************************************************** */

READ_CHUNK (read_gama)
{
#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_READ_GAMA, MNG_LC_START)
#endif
                                       /* sequence checks */
#ifdef MNG_INCLUDE_JNG
  if ((!pData->bHasMHDR) && (!pData->bHasIHDR) &&
      (!pData->bHasBASI) && (!pData->bHasDHDR) && (!pData->bHasJHDR))
#else
  if ((!pData->bHasMHDR) && (!pData->bHasIHDR) &&
      (!pData->bHasBASI) && (!pData->bHasDHDR)    )
#endif
    MNG_ERROR (pData, MNG_SEQUENCEERROR)

#ifdef MNG_INCLUDE_JNG
  if ((pData->bHasIDAT) || (pData->bHasPLTE) || (pData->bHasJDAT) || (pData->bHasJDAA))
#else
  if ((pData->bHasIDAT) || (pData->bHasPLTE))
#endif
    MNG_ERROR (pData, MNG_SEQUENCEERROR)

#ifdef MNG_INCLUDE_JNG
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR) || (pData->bHasJHDR))
#else
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
#endif
  {                                    /* length must be exactly 4 */
    if (iRawlen != 4)
      MNG_ERROR (pData, MNG_INVALIDLENGTH)
  }
  else
  {                                    /* length must be empty or exactly 4 */
    if ((iRawlen != 0) && (iRawlen != 4))
      MNG_ERROR (pData, MNG_INVALIDLENGTH)
  }

#ifdef MNG_INCLUDE_JNG
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR) || (pData->bHasJHDR))
#else
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))
#endif
    pData->bHasGAMA = MNG_TRUE;        /* indicate we've got it */
  else
    pData->bHasglobalGAMA = (mng_bool)(iRawlen != 0);

#ifdef MNG_SUPPORT_DISPLAY
#ifdef MNG_INCLUDE_JNG
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR) || (pData->bHasJHDR))
#else
  if ((pData->bHasIHDR) || (pData->bHasBASI) || (pData->bHasDHDR))