diff options
Diffstat (limited to 'tqtinterface/qt4/src/3rdparty/libmng/libmng_read.c')
| -rw-r--r-- | tqtinterface/qt4/src/3rdparty/libmng/libmng_read.c | 696 | 
1 files changed, 696 insertions, 0 deletions
| diff --git a/tqtinterface/qt4/src/3rdparty/libmng/libmng_read.c b/tqtinterface/qt4/src/3rdparty/libmng/libmng_read.c new file mode 100644 index 0000000..e907ad7 --- /dev/null +++ b/tqtinterface/qt4/src/3rdparty/libmng/libmng_read.c @@ -0,0 +1,696 @@ +/* ************************************************************************** */ +/* *             For conditions of distribution and use,                    * */ +/* *                see copyright notice in libmng.h                        * */ +/* ************************************************************************** */ +/* *                                                                        * */ +/* * project   : libmng                                                     * */ +/* * file      : libmng_read.c             copyright (c) 2000 G.Juyn        * */ +/* * version   : 1.0.4                                                      * */ +/* *                                                                        * */ +/* * purpose   : Read logic (implementation)                                * */ +/* *                                                                        * */ +/* * author    : G.Juyn                                                     * */ +/* * web       : http://www.3-t.com                                         * */ +/* * email     : mailto:info@3-t.com                                        * */ +/* *                                                                        * */ +/* * comment   : implementation of the high-level read logic                * */ +/* *                                                                        * */ +/* * changes   : 0.5.1 - 05/08/2000 - G.Juyn                                * */ +/* *             - changed strict-ANSI stuff                                * */ +/* *             0.5.1 - 05/11/2000 - G.Juyn                                * */ +/* *             - added callback error-reporting support                   * */ +/* *             0.5.1 - 05/12/2000 - G.Juyn                                * */ +/* *             - changed trace to macro for callback error-reporting      * */ +/* *                                                                        * */ +/* *             0.5.2 - 05/19/2000 - G.Juyn                                * */ +/* *             - cleaned up some code regarding mixed support             * */ +/* *             0.5.2 - 05/20/2000 - G.Juyn                                * */ +/* *             - added support for JNG                                    * */ +/* *             0.5.2 - 05/31/2000 - G.Juyn                                * */ +/* *             - fixed up punctuation (contribution by Tim Rowley)        * */ +/* *                                                                        * */ +/* *             0.5.3 - 06/16/2000 - G.Juyn                                * */ +/* *             - changed progressive-display processing                   * */ +/* *                                                                        * */ +/* *             0.9.1 - 07/08/2000 - G.Juyn                                * */ +/* *             - changed read-processing for improved I/O-suspension      * */ +/* *             0.9.1 - 07/14/2000 - G.Juyn                                * */ +/* *             - changed EOF processing behavior                          * */ +/* *             0.9.1 - 07/14/2000 - G.Juyn                                * */ +/* *             - changed default readbuffer size from 1024 to 4200        * */ +/* *                                                                        * */ +/* *             0.9.2 - 07/27/2000 - G.Juyn                                * */ +/* *             - B110320 - fixed GCC warning about mix-sized pointer math * */ +/* *             0.9.2 - 07/31/2000 - G.Juyn                                * */ +/* *             - B110546 - fixed for improperly returning UNEXPECTEDEOF   * */ +/* *             0.9.2 - 08/04/2000 - G.Juyn                                * */ +/* *             - B111096 - fixed large-buffer read-suspension             * */ +/* *             0.9.2 - 08/05/2000 - G.Juyn                                * */ +/* *             - changed file-prefixes                                    * */ +/* *                                                                        * */ +/* *             0.9.3 - 08/26/2000 - G.Juyn                                * */ +/* *             - added MAGN chunk                                         * */ +/* *             0.9.3 - 10/11/2000 - G.Juyn                                * */ +/* *             - removed test-MaGN                                        * */ +/* *             0.9.3 - 10/16/2000 - G.Juyn                                * */ +/* *             - added support for JDAA                                   * */ +/* *                                                                        * */ +/* *             0.9.5 - 01/23/2001 - G.Juyn                                * */ +/* *             - fixed timing-problem with switching framing_modes        * */ +/* *                                                                        * */ +/* *             1.0.4 - 06/22/2002 - G.Juyn                                * */ +/* *             - B495443 - incorrect suspend check in read_databuffer     * */ +/* *                                                                        * */ +/* ************************************************************************** */ + +#include "libmng.h" +#include "libmng_data.h" +#include "libmng_error.h" +#include "libmng_trace.h" +#ifdef __BORLANDC__ +#pragma hdrstop +#endif +#include "libmng_memory.h" +#include "libmng_objects.h" +#include "libmng_object_prc.h" +#include "libmng_chunks.h" +#include "libmng_chunk_prc.h" +#include "libmng_chunk_io.h" +#include "libmng_display.h" +#include "libmng_read.h" + +#if defined(__BORLANDC__) && defined(MNG_STRICT_ANSI) +#pragma option -A                      /* force ANSI-C */ +#endif + +/* ************************************************************************** */ + +#ifdef MNG_INCLUDE_READ_PROCS + +/* ************************************************************************** */ + +mng_retcode process_eof (mng_datap pData) +{ +  if (!pData->bEOF)                    /* haven't closed the stream yet ? */ +  { +    pData->bEOF = MNG_TRUE;            /* now we do! */ + +    if (!pData->fClosestream ((mng_handle)pData)) +      MNG_ERROR (pData, MNG_APPIOERROR) +  } + +  return MNG_NOERROR; +} + +/* ************************************************************************** */ + +mng_retcode read_databuffer (mng_datap    pData, +                             mng_uint8p   pBuf, +                             mng_uint32   iSize, +                             mng_uint32 * iRead) +{ +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_DATABUFFER, MNG_LC_START) +#endif + +  if (pData->bSuspensionmode) +  { +    mng_uint8p pTemp; +    mng_uint32 iTemp; + +    *iRead = 0;                        /* let's be negative about the outcome */ + +    if (!pData->pSuspendbuf)           /* need to create a suspension buffer ? */ +    { +      pData->iSuspendbufsize = MNG_SUSPENDBUFFERSIZE; +                                       /* so, create it */ +      MNG_ALLOC (pData, pData->pSuspendbuf, pData->iSuspendbufsize) + +      pData->iSuspendbufleft = 0;      /* make sure to fill it first time */ +      pData->pSuspendbufnext = pData->pSuspendbuf; +    } +                                       /* more than our buffer can hold ? */ +    if (iSize > pData->iSuspendbufsize) +    { +      mng_uint32 iRemain; + +      if (!pData->pReadbufnext)        /* first time ? */ +      { +        if (pData->iSuspendbufleft)    /* do we have some data left ? */ +        {                              /* then copy it */ +          MNG_COPY (pBuf, pData->pSuspendbufnext, pData->iSuspendbufleft) +                                       /* fixup variables */ +          pData->pReadbufnext    = pBuf + pData->iSuspendbufleft; +          pData->pSuspendbufnext = pData->pSuspendbuf; +          pData->iSuspendbufleft = 0; +        } +        else +        { +          pData->pReadbufnext    = pBuf; +        } +      } +                                       /* calculate how much to get */ +      iRemain = iSize - (mng_uint32)(pData->pReadbufnext - pBuf); +                                       /* let's go get it */ +      if (!pData->fReaddata (((mng_handle)pData), pData->pReadbufnext, iRemain, &iTemp)) +        MNG_ERROR (pData, MNG_APPIOERROR); +                                       /* first read after suspension return 0 means EOF */ +      if ((pData->iSuspendpoint) && (iTemp == 0)) +      {                                /* that makes it final */ +        mng_retcode iRetcode = process_eof (pData); + +        if (iRetcode)                  /* on error bail out */ +          return iRetcode; +                                       /* indicate the source is depleted */ +        *iRead = iSize - iRemain + iTemp; +      } +      else +      { +        if (iTemp < iRemain)           /* suspension required ? */ +        { +          pData->pReadbufnext = pData->pReadbufnext + iTemp; +          pData->bSuspended   = MNG_TRUE; +        } +        else +        { +          *iRead = iSize;              /* got it all now ! */ +        } +      } +    } +    else +    {                                  /* need to read some more ? */ +      while ((!pData->bSuspended) && (!pData->bEOF) && (iSize > pData->iSuspendbufleft)) +      {                                /* not enough space left in buffer ? */ +        if (pData->iSuspendbufsize - pData->iSuspendbufleft - +            (mng_uint32)(pData->pSuspendbufnext - pData->pSuspendbuf) < +                                                          MNG_SUSPENDRETQUESTSIZE) +        { +          if (pData->iSuspendbufleft)  /* then lets shift (if there's anything left) */ +            MNG_COPY (pData->pSuspendbuf, pData->pSuspendbufnext, pData->iSuspendbufleft) +                                       /* adjust running pointer */ +          pData->pSuspendbufnext = pData->pSuspendbuf; +        } +                                       /* still not enough room ? */ +        if (pData->iSuspendbufsize - pData->iSuspendbufleft < MNG_SUSPENDRETQUESTSIZE) +          MNG_ERROR (pData, MNG_INTERNALERROR) +                                       /* now read some more data */ +        pTemp = pData->pSuspendbufnext + pData->iSuspendbufleft; + +        if (!pData->fReaddata (((mng_handle)pData), pTemp, MNG_SUSPENDRETQUESTSIZE, &iTemp)) +          MNG_ERROR (pData, MNG_APPIOERROR); +                                       /* adjust fill-counter */ +        pData->iSuspendbufleft += iTemp; +                                       /* first read after suspension returning 0 means EOF */ +        if ((pData->iSuspendpoint) && (iTemp == 0)) +        {                              /* that makes it final */ +          mng_retcode iRetcode = process_eof (pData); + +          if (iRetcode)                /* on error bail out */ +            return iRetcode; + +          if (pData->iSuspendbufleft)  /* return the leftover scraps */ +            MNG_COPY (pBuf, pData->pSuspendbufnext, pData->iSuspendbufleft) +                                       /* and indicate so */ +          *iRead = pData->iSuspendbufleft; +          pData->pSuspendbufnext = pData->pSuspendbuf; +          pData->iSuspendbufleft = 0; +        } +        else +        {                              /* suspension required ? */ +          if ((iSize > pData->iSuspendbufleft) && (iTemp < MNG_SUSPENDRETQUESTSIZE)) +            pData->bSuspended = MNG_TRUE; + +        } + +        pData->iSuspendpoint = 0;      /* reset it here in case we loop back */  +      } + +      if ((!pData->bSuspended) && (!pData->bEOF)) +      {                                /* return the data ! */ +        MNG_COPY (pBuf, pData->pSuspendbufnext, iSize) + +        *iRead = iSize;                /* returned it all */ +                                       /* adjust suspension-buffer variables */ +        pData->pSuspendbufnext += iSize; +        pData->iSuspendbufleft -= iSize; +      } +    } +  } +  else +  { +    if (!pData->fReaddata (((mng_handle)pData), (mng_ptr)pBuf, iSize, iRead)) +    { +      if (*iRead == 0)                 /* suspension required ? */ +        pData->bSuspended = MNG_TRUE; +      else +        MNG_ERROR (pData, MNG_APPIOERROR); +    } +  } + +  pData->iSuspendpoint = 0;            /* safely reset it here ! */ + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_DATABUFFER, MNG_LC_END) +#endif + +  return MNG_NOERROR; +} + +/* ************************************************************************** */ + +mng_retcode process_raw_chunk (mng_datap  pData, +                               mng_uint8p pBuf, +                               mng_uint32 iBuflen) +{ +  /* the table-idea & binary search code was adapted from +     libpng 1.1.0 (pngread.c) */ +  /* NOTE1: the table must remain sorted by chunkname, otherwise the binary +     search will break !!! */ +  /* NOTE2: the tqlayout must remain equal to the header part of all the +     chunk-structures (yes, that means even the pNext and pPrev fields; +     it's wasting a bit of space, but hey, the code is a lot easier) */ + +  mng_chunk_header chunk_unknown = {MNG_UINT_HUH, init_unknown, free_unknown, +                                    read_unknown, write_unknown, 0, 0}; + +  mng_chunk_header chunk_table [] = +  { +    {MNG_UINT_BACK, init_back, free_back, read_back, write_back, 0, 0}, +    {MNG_UINT_BASI, init_basi, free_basi, read_basi, write_basi, 0, 0}, +    {MNG_UINT_CLIP, init_clip, free_clip, read_clip, write_clip, 0, 0}, +    {MNG_UINT_CLON, init_clon, free_clon, read_clon, write_clon, 0, 0}, +    {MNG_UINT_DBYK, init_dbyk, free_dbyk, read_dbyk, write_dbyk, 0, 0}, +    {MNG_UINT_DEFI, init_defi, free_defi, read_defi, write_defi, 0, 0}, +    {MNG_UINT_DHDR, init_dhdr, free_dhdr, read_dhdr, write_dhdr, 0, 0}, +    {MNG_UINT_DISC, init_disc, free_disc, read_disc, write_disc, 0, 0}, +    {MNG_UINT_DROP, init_drop, free_drop, read_drop, write_drop, 0, 0}, +    {MNG_UINT_ENDL, init_endl, free_endl, read_endl, write_endl, 0, 0}, +    {MNG_UINT_FRAM, init_fram, free_fram, read_fram, write_fram, 0, 0}, +    {MNG_UINT_IDAT, init_idat, free_idat, read_idat, write_idat, 0, 0},  /* 12-th element! */ +    {MNG_UINT_IEND, init_iend, free_iend, read_iend, write_iend, 0, 0}, +    {MNG_UINT_IHDR, init_ihdr, free_ihdr, read_ihdr, write_ihdr, 0, 0}, +    {MNG_UINT_IJNG, init_ijng, free_ijng, read_ijng, write_ijng, 0, 0}, +    {MNG_UINT_IPNG, init_ipng, free_ipng, read_ipng, write_ipng, 0, 0}, +#ifdef MNG_INCLUDE_JNG +    {MNG_UINT_JDAA, init_jdaa, free_jdaa, read_jdaa, write_jdaa, 0, 0}, +    {MNG_UINT_JDAT, init_jdat, free_jdat, read_jdat, write_jdat, 0, 0}, +    {MNG_UINT_JHDR, init_jhdr, free_jhdr, read_jhdr, write_jhdr, 0, 0}, +    {MNG_UINT_JSEP, init_jsep, free_jsep, read_jsep, write_jsep, 0, 0}, +    {MNG_UINT_JdAA, init_jdaa, free_jdaa, read_jdaa, write_jdaa, 0, 0}, +#endif +    {MNG_UINT_LOOP, init_loop, free_loop, read_loop, write_loop, 0, 0}, +    {MNG_UINT_MAGN, init_magn, free_magn, read_magn, write_magn, 0, 0}, +    {MNG_UINT_MEND, init_mend, free_mend, read_mend, write_mend, 0, 0}, +    {MNG_UINT_MHDR, init_mhdr, free_mhdr, read_mhdr, write_mhdr, 0, 0}, +    {MNG_UINT_MOVE, init_move, free_move, read_move, write_move, 0, 0}, +    {MNG_UINT_ORDR, init_ordr, free_ordr, read_ordr, write_ordr, 0, 0}, +    {MNG_UINT_PAST, init_past, free_past, read_past, write_past, 0, 0}, +    {MNG_UINT_PLTE, init_plte, free_plte, read_plte, write_plte, 0, 0}, +    {MNG_UINT_PPLT, init_pplt, free_pplt, read_pplt, write_pplt, 0, 0}, +    {MNG_UINT_PROM, init_prom, free_prom, read_prom, write_prom, 0, 0}, +    {MNG_UINT_SAVE, init_save, free_save, read_save, write_save, 0, 0}, +    {MNG_UINT_SEEK, init_seek, free_seek, read_seek, write_seek, 0, 0}, +    {MNG_UINT_SHOW, init_show, free_show, read_show, write_show, 0, 0}, +    {MNG_UINT_TERM, init_term, free_term, read_term, write_term, 0, 0}, +    {MNG_UINT_bKGD, init_bkgd, free_bkgd, read_bkgd, write_bkgd, 0, 0}, +    {MNG_UINT_cHRM, init_chrm, free_chrm, read_chrm, write_chrm, 0, 0}, +    {MNG_UINT_eXPI, init_expi, free_expi, read_expi, write_expi, 0, 0}, +    {MNG_UINT_fPRI, init_fpri, free_fpri, read_fpri, write_fpri, 0, 0}, +    {MNG_UINT_gAMA, init_gama, free_gama, read_gama, write_gama, 0, 0}, +    {MNG_UINT_hIST, init_hist, free_hist, read_hist, write_hist, 0, 0}, +    {MNG_UINT_iCCP, init_iccp, free_iccp, read_iccp, write_iccp, 0, 0}, +    {MNG_UINT_iTXt, init_itxt, free_itxt, read_itxt, write_itxt, 0, 0}, +    {MNG_UINT_nEED, init_need, free_need, read_need, write_need, 0, 0}, +/* TODO:     {MNG_UINT_oFFs, 0, 0, 0, 0, 0, 0},  */ +/* TODO:     {MNG_UINT_pCAL, 0, 0, 0, 0, 0, 0},  */ +    {MNG_UINT_pHYg, init_phyg, free_phyg, read_phyg, write_phyg, 0, 0}, +    {MNG_UINT_pHYs, init_phys, free_phys, read_phys, write_phys, 0, 0}, +    {MNG_UINT_sBIT, init_sbit, free_sbit, read_sbit, write_sbit, 0, 0}, +/* TODO:     {MNG_UINT_sCAL, 0, 0, 0, 0, 0, 0},  */ +    {MNG_UINT_sPLT, init_splt, free_splt, read_splt, write_splt, 0, 0}, +    {MNG_UINT_sRGB, init_srgb, free_srgb, read_srgb, write_srgb, 0, 0}, +    {MNG_UINT_tEXt, init_text, free_text, read_text, write_text, 0, 0}, +    {MNG_UINT_tIME, init_time, free_time, read_time, write_time, 0, 0}, +    {MNG_UINT_tRNS, init_trns, free_trns, read_trns, write_trns, 0, 0}, +    {MNG_UINT_zTXt, init_ztxt, free_ztxt, read_ztxt, write_ztxt, 0, 0}, +  }; +                                       /* binary search variables */ +  mng_int32         iTop, iLower, iUpper, iMiddle; +  mng_chunk_headerp pEntry;            /* pointer to found entry */ +  mng_chunkid       iChunkname;        /* the chunk's tag */ +  mng_chunkp        pChunk;            /* chunk structure (if #define MNG_STORE_CHUNKS) */ +  mng_retcode       iRetcode;          /* temporary error-code */ + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_PROCESS_RAW_CHUNK, MNG_LC_START) +#endif +                                       /* get the chunkname */ +  iChunkname = (mng_chunkid)(mng_get_uint32 (pBuf)); + +  pBuf += sizeof (mng_chunkid);        /* adjust the buffer */ +  iBuflen -= sizeof (mng_chunkid); +                                       /* determine max index of table */ +  iTop = (sizeof (chunk_table) / sizeof (chunk_table [0])) - 1; + +  /* binary search; with 52 chunks, worst-case is 7 comparisons */ +  iLower  = 0; +  iMiddle = 11;                        /* start with the IDAT entry */ +  iUpper  = iTop; +  pEntry  = 0;                         /* no goods yet! */ +  pChunk  = 0; + +  do                                   /* the binary search itself */ +    { +      if (chunk_table [iMiddle].iChunkname < iChunkname) +        iLower = iMiddle + 1; +      else if (chunk_table [iMiddle].iChunkname > iChunkname) +        iUpper = iMiddle - 1; +      else +      { +        pEntry = &chunk_table [iMiddle]; +        break; +      } + +      iMiddle = (iLower + iUpper) >> 1; +    } +  while (iLower <= iUpper); + +  if (!pEntry)                         /* unknown chunk ? */ +    pEntry = &chunk_unknown;           /* make it so! */ + +  pData->iChunkname = iChunkname;      /* keep track of where we are */ +  pData->iChunkseq++; + +  if (pEntry->fRead)                   /* read-callback available ? */ +  { +    iRetcode = pEntry->fRead (pData, pEntry, iBuflen, (mng_ptr)pBuf, &pChunk); + +    if (!iRetcode)                     /* everything oke ? */ +    {                                  /* remember unknown chunk's id */ +      if ((pChunk) && (pEntry == &chunk_unknown)) +        ((mng_chunk_headerp)pChunk)->iChunkname = iChunkname; +    } +  } +  else +    iRetcode = MNG_NOERROR; + +  if (pChunk)                          /* store this chunk ? */ +    add_chunk (pData, pChunk);         /* do it */ + +#ifdef MNG_INCLUDE_JNG                 /* implicit EOF ? */ +  if ((!pData->bHasMHDR) && (!pData->bHasIHDR) && (!pData->bHasJHDR)) +#else +  if ((!pData->bHasMHDR) && (!pData->bHasIHDR)) +#endif +    iRetcode = process_eof (pData);    /* then do some EOF processing */ + +  if (iRetcode)                        /* on error bail out */ +    return iRetcode; + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_PROCESS_RAW_CHUNK, MNG_LC_END) +#endif + +  return MNG_NOERROR; +} + +/* ************************************************************************** */ + +mng_retcode read_chunk (mng_datap  pData) +{ +  mng_uint32  iBufmax   = pData->iReadbufsize; +  mng_uint8p  pBuf      = pData->pReadbuf; +  mng_uint32  iBuflen   = 0;           /* number of bytes requested */ +  mng_uint32  iRead     = 0;           /* number of bytes read */ +  mng_uint32  iCrc;                    /* calculated CRC */ +  mng_retcode iRetcode  = MNG_NOERROR; + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_CHUNK, MNG_LC_START) +#endif + +#ifdef MNG_SUPPORT_DISPLAY +  if (pData->pCurraniobj)              /* processing an animation object ? */ +  { +    do                                 /* process it then */ +    { +      iRetcode = ((mng_object_headerp)pData->pCurraniobj)->fProcess (pData, pData->pCurraniobj); +                                       /* refresh needed ? */ +/*      if ((!iRetcode) && (!pData->bTimerset) && (pData->bNeedrefresh)) +        iRetcode = display_progressive_refresh (pData, 1); */ +                                       /* can we advance to next object ? */ +      if ((!iRetcode) && (pData->pCurraniobj) && +          (!pData->bTimerset) && (!pData->bSectionwait)) +      { +        pData->pCurraniobj = ((mng_object_headerp)pData->pCurraniobj)->pNext; +                                       /* TERM processing to be done ? */ +        if ((!pData->pCurraniobj) && (pData->bHasTERM) && (!pData->bHasMHDR)) +          iRetcode = process_display_mend (pData); +      } +    }                                  /* until error or a break or no more objects */ +    while ((!iRetcode) && (pData->pCurraniobj) && +           (!pData->bTimerset) && (!pData->bSectionwait) && (!pData->bFreezing)); +  } +  else +  { +    if (pData->iBreakpoint)            /* do we need to finish something first ? */ +    { +      switch (pData->iBreakpoint)      /* return to broken display routine */ +      { +        case 1 : { iRetcode = process_display_fram2 (pData); break; } +        case 2 : { iRetcode = process_display_ihdr  (pData); break; } +        case 3 : ;                     /* same as 4 !!! */ +        case 4 : { iRetcode = process_display_show  (pData); break; } +        case 5 : { iRetcode = process_display_clon2 (pData); break; } +#ifdef MNG_INCLUDE_JNG +        case 7 : { iRetcode = process_display_jhdr  (pData); break; } +#endif +        case 6 : ;                     /* same as 8 !!! */ +        case 8 : { iRetcode = process_display_iend  (pData); break; } +        case 9 : { iRetcode = process_display_magn2 (pData); break; } +      } +    } +  } + +  if (iRetcode)                        /* on error bail out */ +    return iRetcode; + +#endif /* MNG_SUPPORT_DISPLAY */ +                                       /* can we continue processing now, or do we */ +                                       /* need to wait for the timer to finish (again) ? */ +#ifdef MNG_SUPPORT_DISPLAY +  if ((!pData->bTimerset) && (!pData->bSectionwait) && (!pData->bEOF)) +#else +  if (!pData->bEOF) +#endif +  {                                    /* freezing in progress ? */ +    if ((pData->bFreezing) && (pData->iSuspendpoint == 0)) +      pData->bRunning = MNG_FALSE;     /* then this is the right moment to do it */ + +    if (pData->iSuspendpoint <= 2) +    { +      iBuflen  = sizeof (mng_uint32);  /* read length */ +      iRetcode = read_databuffer (pData, pBuf, iBuflen, &iRead); + +      if (iRetcode)                    /* bail on errors */ +        return iRetcode; + +      if (pData->bSuspended)           /* suspended ? */ +        pData->iSuspendpoint = 2; +      else                             /* save the length */ +        pData->iChunklen = mng_get_uint32 (pBuf); + +    } + +    if (!pData->bSuspended)            /* still going ? */ +    {                                  /* previously suspended or not eof ? */ +      if ((pData->iSuspendpoint > 2) || (iRead == iBuflen)) +      {                                /* determine length chunkname + data + crc */ +        iBuflen = pData->iChunklen + (mng_uint32)(sizeof (mng_chunkid) + sizeof (iCrc)); + +        if (iBuflen < iBufmax)         /* does it fit in default buffer ? */ +        {                              /* note that we don't use the full size +                                          so there's always a zero-byte at the +                                          very end !!! */ +          iRetcode = read_databuffer (pData, pBuf, iBuflen, &iRead); + +          if (iRetcode)                /* bail on errors */ +            return iRetcode; + +          if (pData->bSuspended)       /* suspended ? */ +            pData->iSuspendpoint = 3; +          else +          { +            if (iRead != iBuflen)      /* did we get all the data ? */ +              iRetcode = MNG_UNEXPECTEDEOF; +            else +            { +              mng_uint32 iL = iBuflen - (mng_uint32)(sizeof (iCrc)); +                                       /* calculate the crc */ +              iCrc = crc (pData, pBuf, iL); +                                       /* and check it */ +              if (!(iCrc == mng_get_uint32 (pBuf + iL))) +                iRetcode = MNG_INVALIDCRC; +              else +                iRetcode = process_raw_chunk (pData, pBuf, iL); +            } +          } +        } +        else +        { +          if (!pData->iSuspendpoint)   /* create additional large buffer ? */ +          {                            /* again reserve space for the last zero-byte */ +            pData->iLargebufsize = iBuflen + 1; +            MNG_ALLOC (pData, pData->pLargebuf, pData->iLargebufsize) +          } + +          iRetcode = read_databuffer (pData, pData->pLargebuf, iBuflen, &iRead); + +          if (iRetcode) +            return iRetcode; + +          if (pData->bSuspended)       /* suspended ? */ +            pData->iSuspendpoint = 4; +          else +          { +            if (iRead != iBuflen)      /* did we get all the data ? */ +              iRetcode = MNG_UNEXPECTEDEOF; +            else +            { +              mng_uint32 iL = iBuflen - (mng_uint32)(sizeof (iCrc)); +                                       /* calculate the crc */ +              iCrc = crc (pData, pData->pLargebuf, iL); +                                       /* and check it */ +              if (!(iCrc == mng_get_uint32 (pData->pLargebuf + iL))) +                iRetcode = MNG_INVALIDCRC; +              else +                iRetcode = process_raw_chunk (pData, pData->pLargebuf, iL); +            } +                                       /* cleanup additional large buffer */ +            MNG_FREE (pData, pData->pLargebuf, pData->iLargebufsize) +          }   +        } + +        if (iRetcode)                  /* on error bail out */ +          return iRetcode; + +      } +      else +      {                                /* that's final */ +        iRetcode = process_eof (pData); + +        if (iRetcode)                  /* on error bail out */ +          return iRetcode; + +        if ((iRead != 0) ||            /* did we get an unexpected eof ? */ +#ifdef MNG_INCLUDE_JNG +            (pData->bHasIHDR || pData->bHasMHDR || pData->bHasJHDR)) +#else +            (pData->bHasIHDR || pData->bHasMHDR)) +#endif +          MNG_ERROR (pData, MNG_UNEXPECTEDEOF); +      }  +    } +  } + +#ifdef MNG_SUPPORT_DISPLAY             /* refresh needed ? */ +  if ((!pData->bTimerset) && (!pData->bSuspended) && (pData->bNeedrefresh)) +  { +    iRetcode = display_progressive_refresh (pData, 1); + +    if (iRetcode)                      /* on error bail out */ +      return iRetcode; +  } +#endif + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_CHUNK, MNG_LC_END) +#endif + +  return MNG_NOERROR; +} + +/* ************************************************************************** */ + +mng_retcode read_graphic (mng_datap pData) +{ +  mng_uint32  iBuflen;                 /* number of bytes requested */ +  mng_uint32  iRead;                   /* number of bytes read */ +  mng_retcode iRetcode;                /* temporary error-code */ + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_GRAPHIC, MNG_LC_START) +#endif + +  if (!pData->pReadbuf)                /* buffer allocated ? */ +  { +    pData->iReadbufsize = 4200;        /* allocate a default read buffer */ +    MNG_ALLOC (pData, pData->pReadbuf, pData->iReadbufsize) +  } +                                       /* haven't processed the signature ? */ +  if ((!pData->bHavesig) || (pData->iSuspendpoint == 1)) +  { +    iBuflen = 2 * sizeof (mng_uint32); /* read signature */ + +    iRetcode = read_databuffer (pData, pData->pReadbuf, iBuflen, &iRead); + +    if (iRetcode) +      return iRetcode; + +    if (pData->bSuspended)             /* input suspension ? */ +      pData->iSuspendpoint = 1; +    else +    { +      if (iRead != iBuflen)            /* full signature received ? */ +        MNG_ERROR (pData, MNG_UNEXPECTEDEOF); +                                       /* is it a valid signature ? */ +      if (mng_get_uint32 (pData->pReadbuf) == PNG_SIG) +        pData->eSigtype = mng_it_png; +      else +      if (mng_get_uint32 (pData->pReadbuf) == JNG_SIG) +        pData->eSigtype = mng_it_jng; +      else +      if (mng_get_uint32 (pData->pReadbuf) == MNG_SIG) +        pData->eSigtype = mng_it_mng; +      else +        MNG_ERROR (pData, MNG_INVALIDSIG); +                                       /* all of it ? */ +      if (mng_get_uint32 (pData->pReadbuf+4) != POST_SIG) +        MNG_ERROR (pData, MNG_INVALIDSIG); + +      pData->bHavesig = MNG_TRUE; +    } +  } + +  if (!pData->bSuspended)              /* still going ? */ +  { +    do +    { +      iRetcode = read_chunk (pData);   /* process a chunk */ + +      if (iRetcode)                    /* on error bail out */ +        return iRetcode; +    } +#ifdef MNG_SUPPORT_DISPLAY             /* until EOF or a break-request */ +    while (((!pData->bEOF) || (pData->pCurraniobj)) && (!pData->bSuspended) && +           (!pData->bTimerset) && (!pData->bSectionwait)); +#else +    while ((!pData->bEOF) && (!pData->bSuspended)); +#endif +  } + +#ifdef MNG_SUPPORT_TRACE +  MNG_TRACE (pData, MNG_FN_READ_GRAPHIC, MNG_LC_END) +#endif + +  return MNG_NOERROR; +} + +/* ************************************************************************** */ + +#endif /* MNG_INCLUDE_READ_PROCS */ + +/* ************************************************************************** */ +/* * end of file                                                            * */ +/* ************************************************************************** */ + | 
