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-rw-r--r--src/3rdparty/libmng/libmng_read.c696
1 files changed, 696 insertions, 0 deletions
diff --git a/src/3rdparty/libmng/libmng_read.c b/src/3rdparty/libmng/libmng_read.c
new file mode 100644
index 000000000..d4fb2d1a5
--- /dev/null
+++ b/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:[email protected] * */
+/* * * */
+/* * 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 retquired ? */
+ {
+ 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 retquired ? */
+ 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 retquired ? */
+ 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 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) */
+
+ 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 * */
+/* ************************************************************************** */
+
generated by cgit v1.2.1 (git 2.18.0) at 2024-12-27 07:14:29 +0000