1 files changed, 57 insertions, 0 deletions
diff --git a/filter/buffer.c b/filter/buffer.c
new file mode 100644
index 00000000..7b728b9b
--- /dev/null
+++ b/filter/buffer.c
@@ -0,0 +1,57 @@
+#include <fitz.h>
+
+fz_error *
+fz_newbuffer(fz_buffer **bp, int size)
+{
+	fz_buffer *b;
+
+	b = *bp = fz_malloc(sizeof(fz_buffer));
+	if (!b) return fz_outofmem;
+
+	b->bp = fz_malloc(size);
+	if (!b->bp) { fz_free(b); return fz_outofmem; }
+
+	b->rp = b->bp;
+	b->wp = b->bp;
+	b->ep = b->bp + size;
+	b->eof = 0;
+
+	return nil;
+}
+
+void
+fz_freebuffer(fz_buffer *buf)
+{
+	fz_free(buf->bp);
+	fz_free(buf);
+}
+
+fz_error *
+fz_growbuffer(fz_buffer *buf)
+{
+	unsigned char *newbp;
+
+	int rp = buf->rp - buf->bp;
+	int wp = buf->wp - buf->bp;
+	int ep = buf->ep - buf->bp;
+
+	newbp = fz_realloc(buf->bp, ep * 2);
+	if (!newbp) return fz_outofmem;
+
+	buf->bp = newbp;
+	buf->rp = buf->bp + rp;
+	buf->wp = buf->bp + wp;
+	buf->ep = buf->bp + ep * 2;
+
+	return nil;
+}
+
+fz_error *
+fz_rewindbuffer(fz_buffer *buf)
+{
+	memmove(buf->bp, buf->rp, buf->wp - buf->rp);
+	buf->wp = buf->bp + (buf->wp - buf->rp);
+	buf->rp = buf->bp;
+	return nil;
+}
+