new stream api

1 files changed, 33 insertions, 25 deletions

diff --git a/include/fitz/filter.h b/include/fitz/filter.h
index bb33b8eb..f8902f98 100644
--- a/include/fitz/filter.h
+++ b/include/fitz/filter.h
@@ -1,7 +1,29 @@
-typedef struct fz_filter_s fz_filter;
-typedef struct fz_buffer_s fz_buffer;
+/*
+ * Data filters for encryption, compression and decompression.
+ *
+ * A filter has one method, process, that takes an input and an output buffer.
+ *
+ * It returns one of three statuses:
+ *    ioneedin -- input buffer exhausted, please give me more data (wp-rp)
+ *    ioneedout -- output buffer exhausted, please provide more space (ep-wp)
+ *    iodone -- finished, please never call me again. ever!
+ * or...
+ *    any other error object -- oops, something blew up.
+ *
+ * To make using the filter easier, three variables are updated:
+ *    produced -- if we actually produced any new data
+ *    consumed -- like above
+ *    count -- number of bytes produced in total since the beginning
+ *
+ * Most filters take fz_obj as a way to specify parameters.
+ * In most cases, this is a dictionary that contains the same keys
+ * that the corresponding PDF filter would expect.
+ *
+ * The pipeline filter is special, and needs some care when chaining
+ * and unchaining new filters.
+ */
 
-#define FZ_BUFSIZE (32 * 1024)
+typedef struct fz_filter_s fz_filter;
 
 #define fz_ioneedin (&fz_kioneedin)
 #define fz_ioneedout (&fz_kioneedout)
@@ -11,6 +33,10 @@ extern fz_error fz_kioneedin;
 extern fz_error fz_kioneedout;
 extern fz_error fz_kiodone;
 
+/*
+ * Evil looking macro to create an initialize a filter struct.
+ */
+
 #define FZ_NEWFILTER(TYPE,VAR,NAME)                                     \
 	fz_error * fz_process ## NAME (fz_filter*,fz_buffer*,fz_buffer*);   \
 	void fz_drop ## NAME (fz_filter*);                                  \
@@ -35,35 +61,19 @@ struct fz_filter_s
 	int count;
 };
 
-struct fz_buffer_s
-{
-	int refs;
-	int ownsdata;
-	unsigned char *bp;
-	unsigned char *rp;
-	unsigned char *wp;
-	unsigned char *ep;
-	int eof;
-};
-
 fz_error *fz_process(fz_filter *f, fz_buffer *in, fz_buffer *out);
 fz_filter *fz_keepfilter(fz_filter *f);
 void fz_dropfilter(fz_filter *f);
 
-fz_error *fz_newnullfilter(fz_filter **fp, int len);
-fz_error *fz_newarc4filter(fz_filter **fp, unsigned char *key, unsigned keylen);
 fz_error *fz_newpipeline(fz_filter **fp, fz_filter *head, fz_filter *tail);
-
 fz_error *fz_chainpipeline(fz_filter **fp, fz_filter *head, fz_filter *tail, fz_buffer *buf);
 void fz_unchainpipeline(fz_filter *pipe, fz_filter **oldfp, fz_buffer **oldbp);
 
-fz_error *fz_newbuffer(fz_buffer **bufp, int size);
-fz_error *fz_newbufferwithdata(fz_buffer **bufp, unsigned char *data, int size);
-fz_error *fz_rewindbuffer(fz_buffer *buf);
-fz_error *fz_growbuffer(fz_buffer *buf);
-fz_buffer *fz_keepbuffer(fz_buffer *buf);
-void fz_dropbuffer(fz_buffer *buf);
+/* stop and reverse! special case needed for postscript only */
+void fz_pushbackahxd(fz_filter *filter, fz_buffer *in, fz_buffer *out, int n);
 
+fz_error *fz_newnullfilter(fz_filter **fp, int len);
+fz_error *fz_newarc4filter(fz_filter **fp, unsigned char *key, unsigned keylen);
 fz_error *fz_newa85d(fz_filter **filterp, fz_obj *param);
 fz_error *fz_newa85e(fz_filter **filterp, fz_obj *param);
 fz_error *fz_newahxd(fz_filter **filterp, fz_obj *param);
@@ -83,5 +93,3 @@ fz_error *fz_newpredicte(fz_filter **filterp, fz_obj *param);
 fz_error *fz_newjbig2d(fz_filter **filterp, fz_obj *param);
 fz_error *fz_newjpxd(fz_filter **filterp, fz_obj *param);
 
-void fz_pushbackahxd(fz_filter *filter, fz_buffer *in, fz_buffer *out, int n);
-