split out stream filtering

4 files changed, 54 insertions, 4 deletions

diff --git a/src/Makefile b/src/Makefile
index a2d1ae8..35576c2 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,3 +1,3 @@
-DIR_SOURCES := document.c byte_class.c cos_parse.c cos_object.c pdf_doc.c meta.c page.c xref.c
+DIR_SOURCES := document.c byte_class.c cos_parse.c cos_object.c pdf_doc.c meta.c page.c xref.c cos_stream_filter.c
 
 include $(NSBUILD)/Makefile.subdir
diff --git a/src/cos_parse.c b/src/cos_parse.c
index 5448ad4..de85b0c 100644
--- a/src/cos_parse.c
+++ b/src/cos_parse.c
@@ -27,6 +27,7 @@
 /** Maximum length of cos name */
 #define NAME_MAX_LENGTH 127
 
+
 static nspdferror
 cos_string_append(struct cos_string *s, uint8_t c)
 {
@@ -717,8 +718,16 @@ cos_parse_stream(struct nspdf_doc *doc,
     /* optional filter */
     res = cos_get_dictionary_value(doc, stream_dict, "Filter", &stream_filter);
     if (res == NSPDFERROR_OK) {
-        /** \todo filter stream */
-        printf("applying filter %s\n", stream_filter->u.n);
+        const char *filter_name;
+        res = cos_get_name(doc, stream_filter, &filter_name);
+        if (res == NSPDFERROR_OK) {
+            res = nspdf__cos_stream_filter(doc, filter_name, &stream);
+            if (res != NSPDFERROR_OK) {
+                return res;
+            }
+        } else {
+            /** \todo array of filter stream */
+        }
     }
 
     /* allocate stream object */
diff --git a/src/cos_stream_filter.c b/src/cos_stream_filter.c
new file mode 100644
index 0000000..6f407de
--- /dev/null
+++ b/src/cos_stream_filter.c
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2018 Vincent Sanders <vince@netsurf-browser.org>
+ *
+ * This file is part of libnspdf.
+ *
+ * Licensed under the MIT License,
+ *                http://www.opensource.org/licenses/mit-license.php
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <nspdf/errors.h>
+
+#include "cos_object.h"
+#include "pdf_doc.h"
+
+nspdferror
+nspdf__cos_stream_filter(struct nspdf_doc *doc,
+                         const char *filter_name,
+                         struct cos_stream **stream_out)
+{
+    struct cos_stream *stream_in;
+
+    stream_in = *stream_out;
+
+    printf("applying filter %s\n", filter_name);
+    return NSPDFERROR_OK;
+}
diff --git a/src/pdf_doc.h b/src/pdf_doc.h
index b7e6546..e362ea6 100644
--- a/src/pdf_doc.h
+++ b/src/pdf_doc.h
@@ -46,16 +46,18 @@ struct nspdf_doc {
 /* byte data acessory, allows for more complex buffer handling in future */
 #define DOC_BYTE(doc, offset) (doc->start[(offset)])
 
-/* helpers in pdf_doc.h */
+/* helpers in pdf_doc.c */
 nspdferror doc_skip_ws(struct nspdf_doc *doc, uint64_t *offset);
 nspdferror doc_skip_eol(struct nspdf_doc *doc, uint64_t *offset);
 nspdferror doc_read_uint(struct nspdf_doc *doc, uint64_t *offset_out, uint64_t *result_out);
 
+/* cross reference table handlers */
 /**
  * parse xref from file
  */
 nspdferror nspdf__xref_parse(struct nspdf_doc *doc, uint64_t *offset_out);
 
+
 /**
  * get an object dereferencing through xref table if necessary
  */
@@ -65,4 +67,10 @@ nspdferror nspdf__xref_allocate(struct nspdf_doc *doc, int64_t size);
 
 nspdferror nspdf__decode_page_tree(struct nspdf_doc *doc, struct cos_object *page_tree_node, unsigned int *page_index);
 
+/* cos stream filters */
+nspdferror
+nspdf__cos_stream_filter(struct nspdf_doc *doc,
+                         const char *filter_name,
+                         struct cos_stream **stream_out);
+
 #endif