[poppler] Fix for my fix

[Kristian Høgsberg]

Albert Astals Cid wrote:
> Hi, this patch fixes a problem i have seen in a pdf (can not share it) where 
> calling str->reset() to times in DCTStream::reset causes it to misbehave.
> 
> To not call str->reset() and still skip the gargabe we find at the beginning 
> of the stream, i've modified str_fill_input_buffer(...) so that in the two 
> first cases it returns the JPEG markers and then the rest of the data (that 
> will be after the garbage).
> 
> Should the int be declared static? I'm sometimes lost with static when it does 
> not apply to classes.
> 
> What do you think?

The idea of the patch is good, but the integer counter must be part of 
struct str_src_mgr, declared in DCTStream.h and initialized in the 
DCTStream constructor.  With the current global variable, there's only 
one 'i' in the entire program and if you have two DCTStreams in a 
document, only the first one will work.

> 
> Albert
> 
> 
> ------------------------------------------------------------------------
> 
> Index: poppler/DCTStream.cc
> ===================================================================
> RCS file: /cvs/poppler/poppler/poppler/DCTStream.cc,v
> retrieving revision 1.2
> diff -u -r1.2 DCTStream.cc
> --- poppler/DCTStream.cc	25 Jul 2005 20:40:37 -0000	1.2
> +++ poppler/DCTStream.cc	30 Jul 2005 21:11:29 -0000
> @@ -8,6 +8,8 @@
>  
>  #include "DCTStream.h"
>  
> +int i = 0;
> +
>  static void str_init_source(j_decompress_ptr cinfo)
>  {
>  }
> @@ -15,7 +17,15 @@
>  static boolean str_fill_input_buffer(j_decompress_ptr cinfo)
>  {
>    struct str_src_mgr * src = (struct str_src_mgr *)cinfo->src;
> -  src->buffer = src->str->getChar();
> +  if (i == 0) {
> +    src->buffer = 0xFF;
> +    i++;
> +  }
> +  else if (i == 1) {
> +    src->buffer = 0xD8;
> +    i++;
> +  }
> +  else src->buffer = src->str->getChar();
>    src->pub.next_input_byte = &src->buffer;
>    src->pub.bytes_in_buffer = 1;
>    return TRUE;
> @@ -98,10 +108,6 @@
>      n++;
>    }
>  
> -  // ...and this skips the garbage
> -  str->reset();
> -  for (n = n - 2; n > 0; n--) str->getChar();
> -  
>    jpeg_read_header(&cinfo, TRUE);
>    jpeg_start_decompress(&cinfo);
>  
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> poppler mailing list
> poppler at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/poppler