Ejemplo n.º 1
0
/*
 * Build a filter for reading raw stream data.
 * This is a null filter to constrain reading to the
 * stream length, followed by a decryption filter.
 */
static fz_error *
buildrawfilter(fz_filter **filterp, pdf_xref *xref, fz_obj *stmobj, int oid, int gen)
{
	fz_error *error;
	fz_filter *base;
	fz_obj *stmlen;
	int len;

	stmlen = fz_dictgets(stmobj, "Length");
	error = pdf_resolve(&stmlen, xref);
	if (error)
		return fz_rethrow(error, "cannot resolve stream /Length");
	len = fz_toint(stmlen);
	fz_dropobj(stmlen);

	error = fz_newnullfilter(&base, len);
	if (error)
		return fz_rethrow(error, "cannot create null filter");

	if (xref->crypt)
	{
		fz_filter *crypt;
		fz_filter *pipe;

		error = pdf_cryptstream(&crypt, xref->crypt, oid, gen);
		if (error)
		{
			fz_dropfilter(base);
			return fz_rethrow(error, "cannot create decryption filter");
		}

		error = fz_newpipeline(&pipe, base, crypt);
		fz_dropfilter(base);
		fz_dropfilter(crypt);
		if (error)
			return fz_rethrow(error, "cannot create pipeline filter");

		*filterp = pipe;
	}
	else
	{
		*filterp = base;
	}

	return fz_okay;
}
Ejemplo n.º 2
0
static fz_error *
writestream(fz_stream *out, pdf_xref *xref, pdf_crypt *encrypt, int oid, int gen)
{
	fz_error *error;
	fz_stream *dststm;
	fz_stream *srcstm;
	unsigned char buf[4096];
	fz_filter *ef;
	int n;

	fz_print(out, "stream\n");

	if (encrypt)
	{
		error = pdf_cryptstream(&ef, encrypt, oid, gen);
		if (error)
			return error;

		error = fz_openrfilter(&dststm, ef, out);
		fz_dropfilter(ef);
		if (error)
			return error;
	}
	else
	{
		dststm = fz_keepstream(out);
	}

	error = pdf_openrawstream(&srcstm, xref, oid, gen);
	if (error)
		goto cleanupdst;

	while (1)
	{
		n = fz_read(srcstm, buf, sizeof buf);
		if (n == 0)
			break;
		if (n < 0)
		{
			error = fz_ioerror(srcstm);
			goto cleanupsrc;
		}

		n = fz_write(dststm, buf, n);
		if (n < 0)
		{
			error = fz_ioerror(dststm);
			goto cleanupsrc;
		}
	}

	fz_dropstream(srcstm);
	fz_dropstream(dststm);

	fz_print(out, "endstream\n");

	return nil;

cleanupsrc:
	fz_dropstream(srcstm);
cleanupdst:
	fz_dropstream(dststm);
	return error;
}