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attempt to skip the right number of bytes in long-form segment references.
attempt to read long page association fields properly. both untested.


git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@28 ded80894-8fb9-0310-811b-c03f3676ab4d

--- a/jbig2dec.c

+++ b/jbig2dec.c

@@ -8,7 +8,7 @@

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

-    $Id: jbig2dec.c,v 1.6 2001/06/12 23:35:53 giles Exp $

+    $Id: jbig2dec.c,v 1.7 2001/06/14 08:25:01 giles Exp $

 */

 #include <stdio.h>

@@ -122,10 +122,10 @@

 jbig2_read_segment_header (Jbig2Ctx *ctx)

 {

   Jbig2SegmentHeader *result = (Jbig2SegmentHeader *)malloc(sizeof(Jbig2SegmentHeader));

-  int offset = ctx->offset;

-  byte rtscarf;

-  int referred_to_segment_count;

-  byte spa;

+  int	offset = ctx->offset;

+  byte	rtscarf;

+  int32	rtscarf_long;

+  int	referred_to_segment_count;

   /* 7.2.2 */

   result->segment_number = get_int32 (ctx, offset);

@@ -137,8 +137,12 @@

   get_bytes (ctx, &rtscarf, 1, offset + 5);

   if ((rtscarf & 0xe0) == 0xe0)

     {

-      printf ("long form of rtscarf, can't handle!\n");

-    }

+		/* FIXME: we break on non-seekable streams with this,

+		   but for now it's shorter */

+		rtscarf_long = get_int32(ctx, offset + 5);

+		referred_to_segment_count = (rtscarf_long & 0x1ffffffc) >> 2;

+		offset += 5 + 4 + (referred_to_segment_count + 1)/8;

+	}

   else

     {

       referred_to_segment_count = (rtscarf >> 5);

@@ -148,16 +152,19 @@

   /* todo: read referred to segment numbers */

   /* 7.2.6 */

-  get_bytes (ctx, &spa, 1, offset);

-  if (result->flags & 64)

-    {

-      printf ("long form of spa, can't handle!\n");

-    }

-  result->page_association = spa;

-

+  if (result->flags & 0x40) {

+	result->page_association = get_int32(ctx, offset);

+	offset += 4;

+  } else {

+	byte spa;

+	get_bytes (ctx, &spa, 1, offset);

+	result->page_association = spa;

+	offset += 1;

+  }

+  

   /* 7.2.7 */

-  result->data_length = get_int32 (ctx, offset + 1);

-  ctx->offset = offset + 5;

+  result->data_length = get_int32 (ctx, offset);

+  ctx->offset = offset + 4;

   return result;

 }