lib: add ringbuf_copy()

Quick 'n easy way to copy the contents of one ringbuf to another.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

2 files changed, 19 insertions, 0 deletions

diff --git a/lib/ringbuf.c b/lib/ringbuf.c
index f8e9a9bd8a..d4efbe05fb 100644
--- a/lib/ringbuf.c
+++ b/lib/ringbuf.c
@@ -110,6 +110,15 @@ size_t ringbuf_peek(struct ringbuf *buf, size_t offset, void *data, size_t size)
 	return copysize;
 }
 
+size_t ringbuf_copy(struct ringbuf *to, struct ringbuf *from, size_t size)
+{
+	size_t tocopy = MIN(ringbuf_space(to), size);
+	uint8_t *cbuf = XCALLOC(MTYPE_TMP, tocopy);
+	tocopy = ringbuf_peek(from, 0, cbuf, tocopy);
+	XFREE(MTYPE_TMP, cbuf);
+	return ringbuf_put(to, cbuf, tocopy);
+}
+
 void ringbuf_reset(struct ringbuf *buf)
 {
 	buf->start = buf->end = 0;
diff --git a/lib/ringbuf.h b/lib/ringbuf.h
index 2288a2716f..15049e3eea 100644
--- a/lib/ringbuf.h
+++ b/lib/ringbuf.h
@@ -99,6 +99,16 @@ size_t ringbuf_peek(struct ringbuf *buf, size_t offset, void *data,
 		    size_t size);
 
 /*
+ * Copy data from one ringbuf to another.
+ *
+ * @param to	destination ringbuf
+ * @param from	source ringbuf
+ * @param size	how much data to copy
+ * @return amount of data copied
+ */
+size_t ringbuf_copy(struct ringbuf *to, struct ringbuf *from, size_t size);
+
+/*
  * Reset buffer. Does not wipe.
  *
  * @param buf