src/3rdparty/libmng/libmng_read.c
changeset 0 1918ee327afb
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/3rdparty/libmng/libmng_read.c	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,1369 @@
+/* ************************************************************************** */
+/* *             For conditions of distribution and use,                    * */
+/* *                see copyright notice in libmng.h                        * */
+/* ************************************************************************** */
+/* *                                                                        * */
+/* * project   : libmng                                                     * */
+/* * file      : libmng_read.c             copyright (c) 2000-2007 G.Juyn   * */
+/* * version   : 1.0.10                                                     * */
+/* *                                                                        * */
+/* * purpose   : Read logic (implementation)                                * */
+/* *                                                                        * */
+/* * author    : G.Juyn                                                     * */
+/* *                                                                        * */
+/* * 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     * */
+/* *                                                                        * */
+/* *             1.0.5 - 07/04/2002 - G.Juyn                                * */
+/* *             - added errorcode for extreme chunk-sizes                  * */
+/* *             1.0.5 - 07/08/2002 - G.Juyn                                * */
+/* *             - B578572 - removed eMNGma hack (thanks Dimitri!)          * */
+/* *             1.0.5 - 07/16/2002 - G.Juyn                                * */
+/* *             - B581625 - large chunks fail with suspension reads        * */
+/* *             1.0.5 - 08/19/2002 - G.Juyn                                * */
+/* *             - B597134 - libmng pollutes the linker namespace           * */
+/* *             - added HLAPI function to copy chunks                      * */
+/* *             1.0.5 - 09/16/2002 - G.Juyn                                * */
+/* *             - added event handling for dynamic MNG                     * */
+/* *                                                                        * */
+/* *             1.0.6 - 05/25/2003 - G.R-P                                 * */
+/* *             - added MNG_SKIPCHUNK_cHNK footprint optimizations         * */
+/* *             1.0.6 - 07/07/2003 - G.R-P                                 * */
+/* *             - added MNG_NO_DELTA_PNG reduction                         * */
+/* *             - skip additional code when MNG_INCLUDE_JNG is not enabled * */
+/* *             1.0.6 - 07/29/2003 - G.R-P                                 * */
+/* *             - added conditionals around PAST chunk support             * */
+/* *             1.0.6 - 08/17/2003 - G.R-P                                 * */
+/* *             - added conditionals around non-VLC chunk support          * */
+/* *                                                                        * */
+/* *             1.0.7 - 03/10/2004 - G.R-P                                 * */
+/* *             - added conditionals around openstream/closestream         * */
+/* *                                                                        * */
+/* *             1.0.8 - 04/08/2004 - G.Juyn                                * */
+/* *             - added CRC existence & checking flags                     * */
+/* *             1.0.8 - 04/11/2004 - G.Juyn                                * */
+/* *             - added data-push mechanisms for specialized decoders      * */
+/* *             1.0.8 - 07/06/2004 - G.R-P                                 * */
+/* *             - defend against using undefined closestream function      * */
+/* *             1.0.8 - 07/28/2004 - G.R-P                                 * */
+/* *             - added check for extreme chunk-lengths                    * */
+/* *                                                                        * */
+/* *             1.0.9 - 09/16/2004 - G.Juyn                                * */
+/* *             - fixed chunk pushing mechanism                            * */
+/* *             1.0.9 - 12/05/2004 - G.Juyn                                * */
+/* *             - added conditional MNG_OPTIMIZE_CHUNKINITFREE             * */
+/* *             1.0.9 - 12/06/2004 - G.Juyn                                * */
+/* *             - added conditional MNG_OPTIMIZE_CHUNKASSIGN               * */
+/* *             - added conditional MNG_OPTIMIZE_CHUNKREADER               * */
+/* *             1.0.9 - 12/20/2004 - G.Juyn                                * */
+/* *             - cleaned up macro-invocations (thanks to D. Airlie)       * */
+/* *             1.0.9 - 12/31/2004 - G.R-P                                 * */
+/* *             - removed stray characters from #ifdef directive           * */
+/* *                                                                        * */
+/* *             1.0.10 - 04/08/2007 - G.Juyn                               * */
+/* *             - added support for mPNG proposal                          * */
+/* *                                                                        * */
+/* ************************************************************************** */
+
+#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"
+#ifdef MNG_OPTIMIZE_CHUNKREADER
+#include "libmng_chunk_descr.h"
+#endif
+#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 mng_process_eof (mng_datap pData)
+{
+  if (!pData->bEOF)                    /* haven't closed the stream yet ? */
+  {
+    pData->bEOF = MNG_TRUE;            /* now we do! */
+
+#ifndef MNG_NO_OPEN_CLOSE_STREAM
+    if (pData->fClosestream && !pData->fClosestream ((mng_handle)pData))
+    {
+      MNG_ERROR (pData, MNG_APPIOERROR);
+    }
+#endif
+  }
+
+  return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_release_pushdata (mng_datap pData)
+{
+  mng_pushdatap pFirst  = pData->pFirstpushdata;
+  mng_pushdatap pNext   = pFirst->pNext;
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_RELEASE_PUSHDATA, MNG_LC_START);
+#endif
+
+  pData->pFirstpushdata = pNext;       /* next becomes the first */
+
+  if (!pNext)                          /* no next? => no last! */
+    pData->pLastpushdata = MNG_NULL;
+                                       /* buffer owned and release callback defined? */
+  if ((pFirst->bOwned) && (pData->fReleasedata))
+    pData->fReleasedata ((mng_handle)pData, pFirst->pData, pFirst->iLength);
+  else                                 /* otherwise use internal free mechanism */
+    MNG_FREEX (pData, pFirst->pData, pFirst->iLength);
+                                       /* and free it */
+  MNG_FREEX (pData, pFirst, sizeof(mng_pushdata));
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_RELEASE_PUSHDATA, MNG_LC_END);
+#endif
+
+  return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_release_pushchunk (mng_datap pData)
+{
+  mng_pushdatap pFirst  = pData->pFirstpushchunk;
+  mng_pushdatap pNext   = pFirst->pNext;
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_RELEASE_PUSHCHUNK, MNG_LC_START);
+#endif
+
+  pData->pFirstpushchunk = pNext;      /* next becomes the first */
+
+  if (!pNext)                          /* no next? => no last! */
+    pData->pLastpushchunk = MNG_NULL;
+                                       /* buffer owned and release callback defined? */
+  if ((pFirst->bOwned) && (pData->fReleasedata))
+    pData->fReleasedata ((mng_handle)pData, pFirst->pData, pFirst->iLength);
+  else                                 /* otherwise use internal free mechanism */
+    MNG_FREEX (pData, pFirst->pData, pFirst->iLength);
+                                       /* and free it */
+  MNG_FREEX (pData, pFirst, sizeof(mng_pushdata));
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_RELEASE_PUSHCHUNK, MNG_LC_END);
+#endif
+
+  return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode read_data (mng_datap    pData,
+                                 mng_uint8p   pBuf,
+                                 mng_uint32   iSize,
+                                 mng_uint32 * iRead)
+{
+  mng_retcode   iRetcode;
+  mng_uint32    iTempsize = iSize;
+  mng_uint8p    pTempbuf  = pBuf;
+  mng_pushdatap pPush     = pData->pFirstpushdata;
+  mng_uint32    iPushsize = 0;
+  *iRead                  = 0;         /* nothing yet */
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_READ_DATA, MNG_LC_START);
+#endif
+
+  while (pPush)                        /* calculate size of pushed data */
+  {
+    iPushsize += pPush->iRemaining;
+    pPush      = pPush->pNext;
+  }
+
+  if (iTempsize <= iPushsize)          /* got enough push data? */
+  {
+    while (iTempsize)
+    {
+      pPush = pData->pFirstpushdata;
+                                       /* enough data remaining in this buffer? */
+      if (pPush->iRemaining <= iTempsize)
+      {                                /* no: then copy what we've got */
+        MNG_COPY (pTempbuf, pPush->pDatanext, pPush->iRemaining);
+                                       /* move pointers & lengths */
+        pTempbuf  += pPush->iRemaining;
+        *iRead    += pPush->iRemaining;
+        iTempsize -= pPush->iRemaining;
+                                       /* release the depleted buffer */
+        iRetcode = mng_release_pushdata (pData);
+        if (iRetcode)
+          return iRetcode;
+      }
+      else
+      {                                /* copy the needed bytes */
+        MNG_COPY (pTempbuf, pPush->pDatanext, iTempsize);
+                                       /* move pointers & lengths */
+        pPush->iRemaining -= iTempsize;
+        pPush->pDatanext  += iTempsize;
+        pTempbuf          += iTempsize;
+        *iRead            += iTempsize;
+        iTempsize         = 0;         /* all done!!! */
+      }
+    }
+  }
+  else
+  {
+    mng_uint32 iTempread = 0;
+                                       /* get it from the app then */
+    if (!pData->fReaddata (((mng_handle)pData), pTempbuf, iTempsize, &iTempread))
+      MNG_ERROR (pData, MNG_APPIOERROR);
+
+    *iRead += iTempread;
+  }
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_READ_DATA, MNG_LC_END);
+#endif
+
+  return MNG_NOERROR;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL mng_retcode read_databuffer (mng_datap    pData,
+                                       mng_uint8p   pBuf,
+                                       mng_uint8p * pBufnext,
+                                       mng_uint32   iSize,
+                                       mng_uint32 * iRead)
+{
+  mng_retcode iRetcode;
+  
+#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 (!*pBufnext)                  /* first time ? */
+      {
+        if (pData->iSuspendbufleft)    /* do we have some data left ? */
+        {                              /* then copy it */
+          MNG_COPY (pBuf, pData->pSuspendbufnext, pData->iSuspendbufleft);
+                                       /* fixup variables */
+          *pBufnext              = pBuf + pData->iSuspendbufleft;
+          pData->pSuspendbufnext = pData->pSuspendbuf;
+          pData->iSuspendbufleft = 0;
+        }
+        else
+        {
+          *pBufnext              = pBuf;
+        }
+      }
+                                       /* calculate how much to get */
+      iRemain = iSize - (mng_uint32)(*pBufnext - pBuf);
+                                       /* let's go get it */
+      iRetcode = read_data (pData, *pBufnext, iRemain, &iTemp);
+      if (iRetcode)
+        return iRetcode;
+                                       /* first read after suspension return 0 means EOF */
+      if ((pData->iSuspendpoint) && (iTemp == 0))
+      {                                /* that makes it final */
+        mng_retcode iRetcode = mng_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 ? */
+        {
+          *pBufnext         = *pBufnext + 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_SUSPENDREQUESTSIZE)
+        {
+          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_SUSPENDREQUESTSIZE)
+          MNG_ERROR (pData, MNG_INTERNALERROR);
+                                       /* now read some more data */
+        pTemp = pData->pSuspendbufnext + pData->iSuspendbufleft;
+
+        iRetcode = read_data (pData, pTemp, MNG_SUSPENDREQUESTSIZE, &iTemp);
+        if (iRetcode)
+          return iRetcode;
+                                       /* 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 = mng_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_SUSPENDREQUESTSIZE))
+            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
+  {
+    iRetcode = read_data (pData, (mng_ptr)pBuf, iSize, iRead);
+    if (iRetcode)
+      return iRetcode;
+    if (*iRead == 0)                   /* suspension required ? */
+      pData->bSuspended = MNG_TRUE;
+  }
+
+  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_LOCAL mng_retcode process_raw_chunk (mng_datap  pData,
+                                         mng_uint8p pBuf,
+                                         mng_uint32 iBuflen)
+{
+
+#ifndef MNG_OPTIMIZE_CHUNKREADER
+  /* 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 !!! (ps. watch upper-/lower-case chunknames !!) */
+  /* NOTE2: the layout 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) */
+
+#ifdef MNG_OPTIMIZE_CHUNKINITFREE
+  mng_chunk_header mng_chunk_unknown = {MNG_UINT_HUH, mng_init_general, mng_free_unknown,
+                                        mng_read_unknown, mng_write_unknown, mng_assign_unknown, 0, 0, sizeof(mng_unknown_chunk)};
+#else
+  mng_chunk_header mng_chunk_unknown = {MNG_UINT_HUH, mng_init_unknown, mng_free_unknown,
+                                        mng_read_unknown, mng_write_unknown, mng_assign_unknown, 0, 0};
+#endif
+
+#ifdef MNG_OPTIMIZE_CHUNKINITFREE
+
+  mng_chunk_header mng_chunk_table [] =
+  {
+#ifndef MNG_SKIPCHUNK_BACK
+    {MNG_UINT_BACK, mng_init_general, mng_free_general, mng_read_back, mng_write_back, mng_assign_general, 0, 0, sizeof(mng_back)},
+#endif
+#ifndef MNG_SKIPCHUNK_BASI
+    {MNG_UINT_BASI, mng_init_general, mng_free_general, mng_read_basi, mng_write_basi, mng_assign_general, 0, 0, sizeof(mng_basi)},
+#endif
+#ifndef MNG_SKIPCHUNK_CLIP
+    {MNG_UINT_CLIP, mng_init_general, mng_free_general, mng_read_clip, mng_write_clip, mng_assign_general, 0, 0, sizeof(mng_clip)},
+#endif
+#ifndef MNG_SKIPCHUNK_CLON
+    {MNG_UINT_CLON, mng_init_general, mng_free_general, mng_read_clon, mng_write_clon, mng_assign_general, 0, 0, sizeof(mng_clon)},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_DBYK
+    {MNG_UINT_DBYK, mng_init_general, mng_free_dbyk,    mng_read_dbyk, mng_write_dbyk, mng_assign_dbyk,    0, 0, sizeof(mng_dbyk)},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_DEFI
+    {MNG_UINT_DEFI, mng_init_general, mng_free_general, mng_read_defi, mng_write_defi, mng_assign_general, 0, 0, sizeof(mng_defi)},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+    {MNG_UINT_DHDR, mng_init_general, mng_free_general, mng_read_dhdr, mng_write_dhdr, mng_assign_general, 0, 0, sizeof(mng_dhdr)},
+#endif
+#ifndef MNG_SKIPCHUNK_DISC
+    {MNG_UINT_DISC, mng_init_general, mng_free_disc,    mng_read_disc, mng_write_disc, mng_assign_disc,    0, 0, sizeof(mng_disc)},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_DROP
+    {MNG_UINT_DROP, mng_init_general, mng_free_drop,    mng_read_drop, mng_write_drop, mng_assign_drop,    0, 0, sizeof(mng_drop)},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_LOOP
+    {MNG_UINT_ENDL, mng_init_general, mng_free_general, mng_read_endl, mng_write_endl, mng_assign_general, 0, 0, sizeof(mng_endl)},
+#endif
+#ifndef MNG_SKIPCHUNK_FRAM
+    {MNG_UINT_FRAM, mng_init_general, mng_free_fram,    mng_read_fram, mng_write_fram, mng_assign_fram,    0, 0, sizeof(mng_fram)},
+#endif
+    {MNG_UINT_IDAT, mng_init_general, mng_free_idat,    mng_read_idat, mng_write_idat, mng_assign_idat,    0, 0, sizeof(mng_idat)},  /* 12-th element! */
+    {MNG_UINT_IEND, mng_init_general, mng_free_general, mng_read_iend, mng_write_iend, mng_assign_general, 0, 0, sizeof(mng_iend)},
+    {MNG_UINT_IHDR, mng_init_general, mng_free_general, mng_read_ihdr, mng_write_ihdr, mng_assign_general, 0, 0, sizeof(mng_ihdr)},
+#ifndef MNG_NO_DELTA_PNG
+#ifdef MNG_INCLUDE_JNG
+    {MNG_UINT_IJNG, mng_init_general, mng_free_general, mng_read_ijng, mng_write_ijng, mng_assign_general, 0, 0, sizeof(mng_ijng)},
+#endif
+    {MNG_UINT_IPNG, mng_init_general, mng_free_general, mng_read_ipng, mng_write_ipng, mng_assign_general, 0, 0, sizeof(mng_ipng)},
+#endif
+#ifdef MNG_INCLUDE_JNG
+    {MNG_UINT_JDAA, mng_init_general, mng_free_jdaa,    mng_read_jdaa, mng_write_jdaa, mng_assign_jdaa,    0, 0, sizeof(mng_jdaa)},
+    {MNG_UINT_JDAT, mng_init_general, mng_free_jdat,    mng_read_jdat, mng_write_jdat, mng_assign_jdat,    0, 0, sizeof(mng_jdat)},
+    {MNG_UINT_JHDR, mng_init_general, mng_free_general, mng_read_jhdr, mng_write_jhdr, mng_assign_general, 0, 0, sizeof(mng_jhdr)},
+    {MNG_UINT_JSEP, mng_init_general, mng_free_general, mng_read_jsep, mng_write_jsep, mng_assign_general, 0, 0, sizeof(mng_jsep)},
+    {MNG_UINT_JdAA, mng_init_general, mng_free_jdaa,    mng_read_jdaa, mng_write_jdaa, mng_assign_jdaa,    0, 0, sizeof(mng_jdaa)},
+#endif
+#ifndef MNG_SKIPCHUNK_LOOP
+    {MNG_UINT_LOOP, mng_init_general, mng_free_loop,    mng_read_loop, mng_write_loop, mng_assign_loop,    0, 0, sizeof(mng_loop)},
+#endif
+#ifndef MNG_SKIPCHUNK_MAGN
+    {MNG_UINT_MAGN, mng_init_general, mng_free_general, mng_read_magn, mng_write_magn, mng_assign_general, 0, 0, sizeof(mng_magn)},
+#endif
+    {MNG_UINT_MEND, mng_init_general, mng_free_general, mng_read_mend, mng_write_mend, mng_assign_general, 0, 0, sizeof(mng_mend)},
+    {MNG_UINT_MHDR, mng_init_general, mng_free_general, mng_read_mhdr, mng_write_mhdr, mng_assign_general, 0, 0, sizeof(mng_mhdr)},
+#ifndef MNG_SKIPCHUNK_MOVE
+    {MNG_UINT_MOVE, mng_init_general, mng_free_general, mng_read_move, mng_write_move, mng_assign_general, 0, 0, sizeof(mng_move)},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_ORDR
+    {MNG_UINT_ORDR, mng_init_general, mng_free_ordr,    mng_read_ordr, mng_write_ordr, mng_assign_ordr,    0, 0, sizeof(mng_ordr)},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_PAST
+    {MNG_UINT_PAST, mng_init_general, mng_free_past,    mng_read_past, mng_write_past, mng_assign_past,    0, 0, sizeof(mng_past)},
+#endif
+    {MNG_UINT_PLTE, mng_init_general, mng_free_general, mng_read_plte, mng_write_plte, mng_assign_general, 0, 0, sizeof(mng_plte)},
+#ifndef MNG_NO_DELTA_PNG
+    {MNG_UINT_PPLT, mng_init_general, mng_free_general, mng_read_pplt, mng_write_pplt, mng_assign_general, 0, 0, sizeof(mng_pplt)},
+    {MNG_UINT_PROM, mng_init_general, mng_free_general, mng_read_prom, mng_write_prom, mng_assign_general, 0, 0, sizeof(mng_prom)},
+#endif
+#ifndef MNG_SKIPCHUNK_SAVE
+    {MNG_UINT_SAVE, mng_init_general, mng_free_save,    mng_read_save, mng_write_save, mng_assign_save,    0, 0, sizeof(mng_save)},
+#endif
+#ifndef MNG_SKIPCHUNK_SEEK
+    {MNG_UINT_SEEK, mng_init_general, mng_free_seek,    mng_read_seek, mng_write_seek, mng_assign_seek,    0, 0, sizeof(mng_seek)},
+#endif
+#ifndef MNG_SKIPCHUNK_SHOW
+    {MNG_UINT_SHOW, mng_init_general, mng_free_general, mng_read_show, mng_write_show, mng_assign_general, 0, 0, sizeof(mng_show)},
+#endif
+#ifndef MNG_SKIPCHUNK_TERM
+    {MNG_UINT_TERM, mng_init_general, mng_free_general, mng_read_term, mng_write_term, mng_assign_general, 0, 0, sizeof(mng_term)},
+#endif
+#ifndef MNG_SKIPCHUNK_bKGD
+    {MNG_UINT_bKGD, mng_init_general, mng_free_general, mng_read_bkgd, mng_write_bkgd, mng_assign_general, 0, 0, sizeof(mng_bkgd)},
+#endif
+#ifndef MNG_SKIPCHUNK_cHRM
+    {MNG_UINT_cHRM, mng_init_general, mng_free_general, mng_read_chrm, mng_write_chrm, mng_assign_general, 0, 0, sizeof(mng_chrm)},
+#endif
+#ifndef MNG_SKIPCHUNK_eXPI
+    {MNG_UINT_eXPI, mng_init_general, mng_free_expi,    mng_read_expi, mng_write_expi, mng_assign_expi,    0, 0, sizeof(mng_expi)},
+#endif
+#ifndef MNG_SKIPCHUNK_evNT
+    {MNG_UINT_evNT, mng_init_general, mng_free_evnt,    mng_read_evnt, mng_write_evnt, mng_assign_evnt,    0, 0, sizeof(mng_evnt)},
+#endif
+#ifndef MNG_SKIPCHUNK_fPRI
+    {MNG_UINT_fPRI, mng_init_general, mng_free_general, mng_read_fpri, mng_write_fpri, mng_assign_general, 0, 0, sizeof(mng_fpri)},
+#endif
+#ifndef MNG_SKIPCHUNK_gAMA
+    {MNG_UINT_gAMA, mng_init_general, mng_free_general, mng_read_gama, mng_write_gama, mng_assign_general, 0, 0, sizeof(mng_gama)},
+#endif
+#ifndef MNG_SKIPCHUNK_hIST
+    {MNG_UINT_hIST, mng_init_general, mng_free_general, mng_read_hist, mng_write_hist, mng_assign_general, 0, 0, sizeof(mng_hist)},
+#endif
+#ifndef MNG_SKIPCHUNK_iCCP
+    {MNG_UINT_iCCP, mng_init_general, mng_free_iccp,    mng_read_iccp, mng_write_iccp, mng_assign_iccp,    0, 0, sizeof(mng_iccp)},
+#endif
+#ifndef MNG_SKIPCHUNK_iTXt
+    {MNG_UINT_iTXt, mng_init_general, mng_free_itxt,    mng_read_itxt, mng_write_itxt, mng_assign_itxt,    0, 0, sizeof(mng_itxt)},
+#endif
+#ifdef MNG_INCLUDE_MPNG_PROPOSAL
+    {MNG_UINT_mpNG, mng_init_general, mng_free_mpng,    mng_read_mpng, mng_write_mpng, mng_assign_mpng,    0, 0, sizeof(mng_mpng)},
+#endif
+#ifndef MNG_SKIPCHUNK_nEED
+    {MNG_UINT_nEED, mng_init_general, mng_free_need,    mng_read_need, mng_write_need, mng_assign_need,    0, 0, sizeof(mng_need)},
+#endif
+/* TODO:     {MNG_UINT_oFFs, 0, 0, 0, 0, 0, 0},  */
+/* TODO:     {MNG_UINT_pCAL, 0, 0, 0, 0, 0, 0},  */
+#ifndef MNG_SKIPCHUNK_pHYg
+    {MNG_UINT_pHYg, mng_init_general, mng_free_general, mng_read_phyg, mng_write_phyg, mng_assign_general, 0, 0, sizeof(mng_phyg)},
+#endif
+#ifndef MNG_SKIPCHUNK_pHYs
+    {MNG_UINT_pHYs, mng_init_general, mng_free_general, mng_read_phys, mng_write_phys, mng_assign_general, 0, 0, sizeof(mng_phys)},
+#endif
+#ifndef MNG_SKIPCHUNK_sBIT
+    {MNG_UINT_sBIT, mng_init_general, mng_free_general, mng_read_sbit, mng_write_sbit, mng_assign_general, 0, 0, sizeof(mng_sbit)},
+#endif
+/* TODO:     {MNG_UINT_sCAL, 0, 0, 0, 0, 0, 0},  */
+#ifndef MNG_SKIPCHUNK_sPLT
+    {MNG_UINT_sPLT, mng_init_general, mng_free_splt,    mng_read_splt, mng_write_splt, mng_assign_splt,    0, 0, sizeof(mng_splt)},
+#endif
+    {MNG_UINT_sRGB, mng_init_general, mng_free_general, mng_read_srgb, mng_write_srgb, mng_assign_general, 0, 0, sizeof(mng_srgb)},
+#ifndef MNG_SKIPCHUNK_tEXt
+    {MNG_UINT_tEXt, mng_init_general, mng_free_text,    mng_read_text, mng_write_text, mng_assign_text,    0, 0, sizeof(mng_text)},
+#endif
+#ifndef MNG_SKIPCHUNK_tIME
+    {MNG_UINT_tIME, mng_init_general, mng_free_general, mng_read_time, mng_write_time, mng_assign_general, 0, 0, sizeof(mng_time)},
+#endif
+    {MNG_UINT_tRNS, mng_init_general, mng_free_general, mng_read_trns, mng_write_trns, mng_assign_general, 0, 0, sizeof(mng_trns)},
+#ifndef MNG_SKIPCHUNK_zTXt
+    {MNG_UINT_zTXt, mng_init_general, mng_free_ztxt,    mng_read_ztxt, mng_write_ztxt, mng_assign_ztxt,    0, 0, sizeof(mng_ztxt)},
+#endif
+  };
+
+#else                        /* MNG_OPTIMIZE_CHUNKINITFREE */
+
+  mng_chunk_header mng_chunk_table [] =
+  {
+#ifndef MNG_SKIPCHUNK_BACK
+    {MNG_UINT_BACK, mng_init_back, mng_free_back, mng_read_back, mng_write_back, mng_assign_back, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_BASI
+    {MNG_UINT_BASI, mng_init_basi, mng_free_basi, mng_read_basi, mng_write_basi, mng_assign_basi, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_CLIP
+    {MNG_UINT_CLIP, mng_init_clip, mng_free_clip, mng_read_clip, mng_write_clip, mng_assign_clip, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_CLON
+    {MNG_UINT_CLON, mng_init_clon, mng_free_clon, mng_read_clon, mng_write_clon, mng_assign_clon, 0, 0},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_DBYK
+    {MNG_UINT_DBYK, mng_init_dbyk, mng_free_dbyk, mng_read_dbyk, mng_write_dbyk, mng_assign_dbyk, 0, 0},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_DEFI
+    {MNG_UINT_DEFI, mng_init_defi, mng_free_defi, mng_read_defi, mng_write_defi, mng_assign_defi, 0, 0},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+    {MNG_UINT_DHDR, mng_init_dhdr, mng_free_dhdr, mng_read_dhdr, mng_write_dhdr, mng_assign_dhdr, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_DISC
+    {MNG_UINT_DISC, mng_init_disc, mng_free_disc, mng_read_disc, mng_write_disc, mng_assign_disc, 0, 0},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_DROP
+    {MNG_UINT_DROP, mng_init_drop, mng_free_drop, mng_read_drop, mng_write_drop, mng_assign_drop, 0, 0},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_LOOP
+    {MNG_UINT_ENDL, mng_init_endl, mng_free_endl, mng_read_endl, mng_write_endl, mng_assign_endl, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_FRAM
+    {MNG_UINT_FRAM, mng_init_fram, mng_free_fram, mng_read_fram, mng_write_fram, mng_assign_fram, 0, 0},
+#endif
+    {MNG_UINT_IDAT, mng_init_idat, mng_free_idat, mng_read_idat, mng_write_idat, mng_assign_idat, 0, 0},  /* 12-th element! */
+    {MNG_UINT_IEND, mng_init_iend, mng_free_iend, mng_read_iend, mng_write_iend, mng_assign_iend, 0, 0},
+    {MNG_UINT_IHDR, mng_init_ihdr, mng_free_ihdr, mng_read_ihdr, mng_write_ihdr, mng_assign_ihdr, 0, 0},
+#ifndef MNG_NO_DELTA_PNG
+#ifdef MNG_INCLUDE_JNG
+    {MNG_UINT_IJNG, mng_init_ijng, mng_free_ijng, mng_read_ijng, mng_write_ijng, mng_assign_ijng, 0, 0},
+#endif
+    {MNG_UINT_IPNG, mng_init_ipng, mng_free_ipng, mng_read_ipng, mng_write_ipng, mng_assign_ipng, 0, 0},
+#endif
+#ifdef MNG_INCLUDE_JNG
+    {MNG_UINT_JDAA, mng_init_jdaa, mng_free_jdaa, mng_read_jdaa, mng_write_jdaa, mng_assign_jdaa, 0, 0},
+    {MNG_UINT_JDAT, mng_init_jdat, mng_free_jdat, mng_read_jdat, mng_write_jdat, mng_assign_jdat, 0, 0},
+    {MNG_UINT_JHDR, mng_init_jhdr, mng_free_jhdr, mng_read_jhdr, mng_write_jhdr, mng_assign_jhdr, 0, 0},
+    {MNG_UINT_JSEP, mng_init_jsep, mng_free_jsep, mng_read_jsep, mng_write_jsep, mng_assign_jsep, 0, 0},
+    {MNG_UINT_JdAA, mng_init_jdaa, mng_free_jdaa, mng_read_jdaa, mng_write_jdaa, mng_assign_jdaa, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_LOOP
+    {MNG_UINT_LOOP, mng_init_loop, mng_free_loop, mng_read_loop, mng_write_loop, mng_assign_loop, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_MAGN
+    {MNG_UINT_MAGN, mng_init_magn, mng_free_magn, mng_read_magn, mng_write_magn, mng_assign_magn, 0, 0},
+#endif
+    {MNG_UINT_MEND, mng_init_mend, mng_free_mend, mng_read_mend, mng_write_mend, mng_assign_mend, 0, 0},
+    {MNG_UINT_MHDR, mng_init_mhdr, mng_free_mhdr, mng_read_mhdr, mng_write_mhdr, mng_assign_mhdr, 0, 0},
+#ifndef MNG_SKIPCHUNK_MOVE
+    {MNG_UINT_MOVE, mng_init_move, mng_free_move, mng_read_move, mng_write_move, mng_assign_move, 0, 0},
+#endif
+#ifndef MNG_NO_DELTA_PNG
+#ifndef MNG_SKIPCHUNK_ORDR
+    {MNG_UINT_ORDR, mng_init_ordr, mng_free_ordr, mng_read_ordr, mng_write_ordr, mng_assign_ordr, 0, 0},
+#endif
+#endif
+#ifndef MNG_SKIPCHUNK_PAST
+    {MNG_UINT_PAST, mng_init_past, mng_free_past, mng_read_past, mng_write_past, mng_assign_past, 0, 0},
+#endif
+    {MNG_UINT_PLTE, mng_init_plte, mng_free_plte, mng_read_plte, mng_write_plte, mng_assign_plte, 0, 0},
+#ifndef MNG_NO_DELTA_PNG
+    {MNG_UINT_PPLT, mng_init_pplt, mng_free_pplt, mng_read_pplt, mng_write_pplt, mng_assign_pplt, 0, 0},
+    {MNG_UINT_PROM, mng_init_prom, mng_free_prom, mng_read_prom, mng_write_prom, mng_assign_prom, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_SAVE
+    {MNG_UINT_SAVE, mng_init_save, mng_free_save, mng_read_save, mng_write_save, mng_assign_save, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_SEEK
+    {MNG_UINT_SEEK, mng_init_seek, mng_free_seek, mng_read_seek, mng_write_seek, mng_assign_seek, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_SHOW
+    {MNG_UINT_SHOW, mng_init_show, mng_free_show, mng_read_show, mng_write_show, mng_assign_show, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_TERM
+    {MNG_UINT_TERM, mng_init_term, mng_free_term, mng_read_term, mng_write_term, mng_assign_term, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_bKGD
+    {MNG_UINT_bKGD, mng_init_bkgd, mng_free_bkgd, mng_read_bkgd, mng_write_bkgd, mng_assign_bkgd, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_cHRM
+    {MNG_UINT_cHRM, mng_init_chrm, mng_free_chrm, mng_read_chrm, mng_write_chrm, mng_assign_chrm, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_eXPI
+    {MNG_UINT_eXPI, mng_init_expi, mng_free_expi, mng_read_expi, mng_write_expi, mng_assign_expi, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_evNT
+    {MNG_UINT_evNT, mng_init_evnt, mng_free_evnt, mng_read_evnt, mng_write_evnt, mng_assign_evnt, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_fPRI
+    {MNG_UINT_fPRI, mng_init_fpri, mng_free_fpri, mng_read_fpri, mng_write_fpri, mng_assign_fpri, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_gAMA
+    {MNG_UINT_gAMA, mng_init_gama, mng_free_gama, mng_read_gama, mng_write_gama, mng_assign_gama, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_hIST
+    {MNG_UINT_hIST, mng_init_hist, mng_free_hist, mng_read_hist, mng_write_hist, mng_assign_hist, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_iCCP
+    {MNG_UINT_iCCP, mng_init_iccp, mng_free_iccp, mng_read_iccp, mng_write_iccp, mng_assign_iccp, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_iTXt
+    {MNG_UINT_iTXt, mng_init_itxt, mng_free_itxt, mng_read_itxt, mng_write_itxt, mng_assign_itxt, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_nEED
+    {MNG_UINT_nEED, mng_init_need, mng_free_need, mng_read_need, mng_write_need, mng_assign_need, 0, 0},
+#endif
+/* TODO:     {MNG_UINT_oFFs, 0, 0, 0, 0, 0, 0},  */
+/* TODO:     {MNG_UINT_pCAL, 0, 0, 0, 0, 0, 0},  */
+#ifndef MNG_SKIPCHUNK_pHYg
+    {MNG_UINT_pHYg, mng_init_phyg, mng_free_phyg, mng_read_phyg, mng_write_phyg, mng_assign_phyg, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_pHYs
+    {MNG_UINT_pHYs, mng_init_phys, mng_free_phys, mng_read_phys, mng_write_phys, mng_assign_phys, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_sBIT
+    {MNG_UINT_sBIT, mng_init_sbit, mng_free_sbit, mng_read_sbit, mng_write_sbit, mng_assign_sbit, 0, 0},
+#endif
+/* TODO:     {MNG_UINT_sCAL, 0, 0, 0, 0, 0, 0},  */
+#ifndef MNG_SKIPCHUNK_sPLT
+    {MNG_UINT_sPLT, mng_init_splt, mng_free_splt, mng_read_splt, mng_write_splt, mng_assign_splt, 0, 0},
+#endif
+    {MNG_UINT_sRGB, mng_init_srgb, mng_free_srgb, mng_read_srgb, mng_write_srgb, mng_assign_srgb, 0, 0},
+#ifndef MNG_SKIPCHUNK_tEXt
+    {MNG_UINT_tEXt, mng_init_text, mng_free_text, mng_read_text, mng_write_text, mng_assign_text, 0, 0},
+#endif
+#ifndef MNG_SKIPCHUNK_tIME
+    {MNG_UINT_tIME, mng_init_time, mng_free_time, mng_read_time, mng_write_time, mng_assign_time, 0, 0},
+#endif
+    {MNG_UINT_tRNS, mng_init_trns, mng_free_trns, mng_read_trns, mng_write_trns, mng_assign_trns, 0, 0},
+#ifndef MNG_SKIPCHUNK_zTXt
+    {MNG_UINT_zTXt, mng_init_ztxt, mng_free_ztxt, mng_read_ztxt, mng_write_ztxt, mng_assign_ztxt, 0, 0},
+#endif
+  };
+
+#endif                       /* MNG_OPTIMIZE_CHUNKINITFREE */
+
+                                       /* binary search variables */
+  mng_int32         iTop, iLower, iUpper, iMiddle;
+  mng_chunk_headerp pEntry;            /* pointer to found entry */
+#else
+  mng_chunk_header  sEntry;            /* temp chunk-header */
+#endif /* MNG_OPTIMIZE_CHUNKREADER */
+
+  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
+                                       /* reset timer indicator on read-cycle */
+  if ((pData->bReading) && (!pData->bDisplaying))
+    pData->bTimerset = MNG_FALSE;
+                                       /* get the chunkname */
+  iChunkname = (mng_chunkid)(mng_get_uint32 (pBuf));
+
+  pBuf += sizeof (mng_chunkid);        /* adjust the buffer */
+  iBuflen -= sizeof (mng_chunkid);
+  pChunk = 0;
+
+#ifndef MNG_OPTIMIZE_CHUNKREADER
+                                       /* determine max index of table */
+  iTop = (sizeof (mng_chunk_table) / sizeof (mng_chunk_table [0])) - 1;
+
+  /* binary search; with 54 chunks, worst-case is 7 comparisons */
+  iLower  = 0;
+#ifndef MNG_NO_DELTA_PNG
+  iMiddle = 11;                        /* start with the IDAT entry */
+#else
+  iMiddle = 8;
+#endif
+  iUpper  = iTop;
+  pEntry  = 0;                         /* no goods yet! */
+
+  do                                   /* the binary search itself */
+    {
+      if (mng_chunk_table [iMiddle].iChunkname < iChunkname)
+        iLower = iMiddle + 1;
+      else if (mng_chunk_table [iMiddle].iChunkname > iChunkname)
+        iUpper = iMiddle - 1;
+      else
+      {
+        pEntry = &mng_chunk_table [iMiddle];
+        break;
+      }
+
+      iMiddle = (iLower + iUpper) >> 1;
+    }
+  while (iLower <= iUpper);
+
+  if (!pEntry)                         /* unknown chunk ? */
+    pEntry = &mng_chunk_unknown;       /* make it so! */
+
+#else /* MNG_OPTIMIZE_CHUNKREADER */
+
+  mng_get_chunkheader (iChunkname, &sEntry);
+
+#endif /* MNG_OPTIMIZE_CHUNKREADER */
+
+  pData->iChunkname = iChunkname;      /* keep track of where we are */
+  pData->iChunkseq++;
+
+#ifndef MNG_OPTIMIZE_CHUNKREADER
+  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->iChunkname == MNG_UINT_HUH))
+        ((mng_chunk_headerp)pChunk)->iChunkname = iChunkname;
+    }
+  }
+#else /* MNG_OPTIMIZE_CHUNKREADER */
+  if (sEntry.fRead)                    /* read-callback available ? */
+  {
+    iRetcode = sEntry.fRead (pData, &sEntry, iBuflen, (mng_ptr)pBuf, &pChunk);
+
+#ifndef MNG_OPTIMIZE_CHUNKREADER
+    if (!iRetcode)                     /* everything oke ? */
+    {                                  /* remember unknown chunk's id */
+      if ((pChunk) && (sEntry.iChunkname == MNG_UINT_HUH))
+        ((mng_chunk_headerp)pChunk)->iChunkname = iChunkname;
+    }
+#endif
+  }
+#endif /* MNG_OPTIMIZE_CHUNKREADER */
+  else
+    iRetcode = MNG_NOERROR;
+
+  if (pChunk)                          /* store this chunk ? */
+    mng_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 = mng_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_LOCAL mng_retcode check_chunk_crc (mng_datap  pData,
+                                       mng_uint8p pBuf,
+                                       mng_uint32 iBuflen)
+{
+  mng_uint32  iCrc;                    /* calculated CRC */
+  mng_bool    bDiscard = MNG_FALSE;
+  mng_retcode iRetcode = MNG_NOERROR;
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_READ_CHUNK_CRC, MNG_LC_START);
+#endif
+
+  if (pData->iCrcmode & MNG_CRC_INPUT) /* crc included ? */
+  {
+    mng_bool bCritical = (mng_bool)((*pBuf & 0x20) == 0);
+    mng_uint32 iL = iBuflen - (mng_uint32)(sizeof (iCrc));
+
+    if (((bCritical ) && (pData->iCrcmode & MNG_CRC_CRITICAL )) ||
+        ((!bCritical) && (pData->iCrcmode & MNG_CRC_ANCILLARY)))
+    {                                  /* calculate the crc */
+      iCrc = mng_crc (pData, pBuf, iL);
+                                       /* and check it */
+      if (!(iCrc == mng_get_uint32 (pBuf + iL)))
+      {
+        mng_bool bWarning = MNG_FALSE;
+        mng_bool bError   = MNG_FALSE;
+
+        if (bCritical)
+        {
+          switch (pData->iCrcmode & MNG_CRC_CRITICAL)
+          {
+            case MNG_CRC_CRITICAL_WARNING  : { bWarning = MNG_TRUE; break; }
+            case MNG_CRC_CRITICAL_ERROR    : { bError   = MNG_TRUE; break; }
+          }
+        }
+        else
+        {
+          switch (pData->iCrcmode & MNG_CRC_ANCILLARY)
+          {
+            case MNG_CRC_ANCILLARY_DISCARD : { bDiscard = MNG_TRUE; break; }
+            case MNG_CRC_ANCILLARY_WARNING : { bWarning = MNG_TRUE; break; }
+            case MNG_CRC_ANCILLARY_ERROR   : { bError   = MNG_TRUE; break; }
+          }
+        }
+
+        if (bWarning)
+          MNG_WARNING (pData, MNG_INVALIDCRC);
+        if (bError)
+          MNG_ERROR (pData, MNG_INVALIDCRC);
+      }
+    }
+
+    if (!bDiscard)                     /* still processing ? */
+      iRetcode = process_raw_chunk (pData, pBuf, iL);
+  }
+  else
+  {                                    /* no crc => straight onto processing */
+    iRetcode = process_raw_chunk (pData, pBuf, iBuflen);
+  }
+
+#ifdef MNG_SUPPORT_TRACE
+  MNG_TRACE (pData, MNG_FN_READ_CHUNK_CRC, MNG_LC_END);
+#endif
+
+  return iRetcode;
+}
+
+/* ************************************************************************** */
+
+MNG_LOCAL 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_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))
+      {                                /* reset timer indicator on read-cycle */
+        if ((pData->bReading) && (!pData->bDisplaying))
+          pData->bTimerset = MNG_FALSE;
+
+        pData->pCurraniobj = ((mng_object_headerp)pData->pCurraniobj)->pNext;
+                                       /* TERM processing to be done ? */
+        if ((!pData->pCurraniobj) && (pData->bHasTERM) && (!pData->bHasMHDR))
+          iRetcode = mng_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 */
+      {
+#ifndef MNG_SKIPCHUNK_FRAM
+        case  1 : { iRetcode = mng_process_display_fram2 (pData); break; }
+#endif
+        case  2 : { iRetcode = mng_process_display_ihdr  (pData); break; }
+#ifndef MNG_SKIPCHUNK_SHOW
+        case  3 : ;                     /* same as 4 !!! */
+        case  4 : { iRetcode = mng_process_display_show  (pData); break; }
+#endif
+#ifndef MNG_SKIPCHUNK_CLON
+        case  5 : { iRetcode = mng_process_display_clon2 (pData); break; }
+#endif
+#ifdef MNG_INCLUDE_JNG
+        case  7 : { iRetcode = mng_process_display_jhdr  (pData); break; }
+#endif
+        case  6 : ;                     /* same as 8 !!! */
+        case  8 : { iRetcode = mng_process_display_iend  (pData); break; }
+#ifndef MNG_SKIPCHUNK_MAGN
+        case  9 : { iRetcode = mng_process_display_magn2 (pData); break; }
+#endif
+        case 10 : { iRetcode = mng_process_display_mend2 (pData); break; }
+#ifndef MNG_SKIPCHUNK_PAST
+        case 11 : { iRetcode = mng_process_display_past2 (pData); break; }
+#endif
+      }
+    }
+  }
+
+  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
+  {
+#ifdef MNG_SUPPORT_DISPLAY
+                                       /* freezing in progress ? */
+    if ((pData->bFreezing) && (pData->iSuspendpoint == 0))
+      pData->bRunning = MNG_FALSE;     /* then this is the right moment to do it */
+#endif
+
+    if (pData->iSuspendpoint <= 2)
+    {
+      iBuflen  = sizeof (mng_uint32);  /* read length */
+      iRetcode = read_databuffer (pData, pBuf, &pData->pReadbufnext, 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->iChunklen > 0x7ffffff)
+           return MNG_INVALIDLENGTH;
+      }
+
+    }
+
+    if (!pData->bSuspended)            /* still going ? */
+    {                                  /* previously suspended or not eof ? */
+      if ((pData->iSuspendpoint > 2) || (iRead == iBuflen))
+      {                                /* determine length chunkname + data (+ crc) */
+        if (pData->iCrcmode & MNG_CRC_INPUT)
+          iBuflen = pData->iChunklen + (mng_uint32)(sizeof (mng_chunkid) + sizeof (mng_uint32));
+        else
+          iBuflen = pData->iChunklen + (mng_uint32)(sizeof (mng_chunkid));
+
+                                       /* do we have enough data in the current push buffer ? */
+        if ((pData->pFirstpushdata) && (iBuflen <= pData->pFirstpushdata->iRemaining))
+        {
+          mng_pushdatap pPush  = pData->pFirstpushdata;
+          pBuf                 = pPush->pDatanext;
+          pPush->pDatanext    += iBuflen;
+          pPush->iRemaining   -= iBuflen;
+          pData->iSuspendpoint = 0;    /* safely reset this here ! */
+
+          iRetcode = check_chunk_crc (pData, pBuf, iBuflen);
+          if (iRetcode)
+            return iRetcode;
+
+          if (!pPush->iRemaining)      /* buffer depleted? then release it */
+            iRetcode = mng_release_pushdata (pData);
+        }
+        else
+        {
+          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, &pData->pReadbufnext, 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 ? */
+                MNG_ERROR (pData, MNG_UNEXPECTEDEOF);
+              iRetcode = check_chunk_crc (pData, pBuf, iBuflen);
+            }
+          }
+          else
+          {
+            if (iBuflen > 16777216)    /* is the length incredible? */
+              MNG_ERROR (pData, MNG_IMPROBABLELENGTH);
+
+            if (!pData->iSuspendpoint) /* create additional large buffer ? */
+            {                          /* again reserve space for the last zero-byte */
+              pData->iLargebufsize = iBuflen + 1;
+              pData->pLargebufnext = MNG_NULL;
+              MNG_ALLOC (pData, pData->pLargebuf, pData->iLargebufsize);
+            }
+
+            iRetcode = read_databuffer (pData, pData->pLargebuf, &pData->pLargebufnext, iBuflen, &iRead);
+            if (iRetcode)
+              return iRetcode;
+
+            if (pData->bSuspended)     /* suspended ? */
+              pData->iSuspendpoint = 4;
+            else
+            {
+              if (iRead != iBuflen)    /* did we get all the data ? */
+                MNG_ERROR (pData, MNG_UNEXPECTEDEOF);
+              iRetcode = check_chunk_crc (pData, pData->pLargebuf, iBuflen);
+                                       /* cleanup additional large buffer */
+              MNG_FREE (pData, pData->pLargebuf, pData->iLargebufsize);
+            }
+          }
+        }
+
+        if (iRetcode)                  /* on error bail out */
+          return iRetcode;
+
+      }
+      else
+      {                                /* that's final */
+        iRetcode = mng_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 = mng_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_LOCAL mng_retcode process_pushedchunk (mng_datap pData)
+{
+  mng_pushdatap pPush;
+  mng_retcode   iRetcode = MNG_NOERROR;
+
+#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))
+      {                                /* reset timer indicator on read-cycle */
+        if ((pData->bReading) && (!pData->bDisplaying))
+          pData->bTimerset = MNG_FALSE;
+
+        pData->pCurraniobj = ((mng_object_headerp)pData->pCurraniobj)->pNext;
+                                       /* TERM processing to be done ? */
+        if ((!pData->pCurraniobj) && (pData->bHasTERM) && (!pData->bHasMHDR))
+          iRetcode = mng_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 */
+      {
+#ifndef MNG_SKIPCHUNK_FRAM
+        case  1 : { iRetcode = mng_process_display_fram2 (pData); break; }
+#endif
+        case  2 : { iRetcode = mng_process_display_ihdr  (pData); break; }
+#ifndef MNG_SKIPCHUNK_SHOW
+        case  3 : ;                     /* same as 4 !!! */
+        case  4 : { iRetcode = mng_process_display_show  (pData); break; }
+#endif
+#ifndef MNG_SKIPCHUNK_CLON
+        case  5 : { iRetcode = mng_process_display_clon2 (pData); break; }
+#endif
+#ifdef MNG_INCLUDE_JNG
+        case  7 : { iRetcode = mng_process_display_jhdr  (pData); break; }
+#endif
+        case  6 : ;                     /* same as 8 !!! */
+        case  8 : { iRetcode = mng_process_display_iend  (pData); break; }
+#ifndef MNG_SKIPCHUNK_MAGN
+        case  9 : { iRetcode = mng_process_display_magn2 (pData); break; }
+#endif
+        case 10 : { iRetcode = mng_process_display_mend2 (pData); break; }
+#ifndef MNG_SKIPCHUNK_PAST
+        case 11 : { iRetcode = mng_process_display_past2 (pData); break; }
+#endif
+      }
+    }
+  }
+
+  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
+  {
+    pData->iSuspendpoint = 0;            /* safely reset it here ! */
+    pPush = pData->pFirstpushchunk;
+
+    iRetcode = process_raw_chunk (pData, pPush->pData, pPush->iLength);
+    if (iRetcode)
+      return iRetcode;
+
+#ifdef MNG_SUPPORT_DISPLAY             /* refresh needed ? */
+    if ((!pData->bTimerset) && (!pData->bSuspended) && (pData->bNeedrefresh))
+    {
+      iRetcode = mng_display_progressive_refresh (pData, 1);
+      if (iRetcode)                      /* on error bail out */
+        return iRetcode;
+    }
+#endif
+  }
+
+  return mng_release_pushchunk (pData);
+}
+
+/* ************************************************************************** */
+
+mng_retcode mng_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, &pData->pReadbufnext, 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
+#ifdef MNG_INCLUDE_JNG
+      if (mng_get_uint32 (pData->pReadbuf) == JNG_SIG)
+        pData->eSigtype = mng_it_jng;
+      else
+#endif
+      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
+    {                                  /* reset timer during mng_read() ? */
+      if ((pData->bReading) && (!pData->bDisplaying))
+        pData->bTimerset = MNG_FALSE;
+
+      if (pData->pFirstpushchunk)      /* chunks pushed ? */
+        iRetcode = process_pushedchunk (pData); /* process the pushed chunk */
+      else
+        iRetcode = read_chunk (pData); /* read & 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->bSectionwait) &&
+           ((!pData->bTimerset) || ((pData->bReading) && (!pData->bDisplaying))));
+#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                                                            * */
+/* ************************************************************************** */
+