This is a wrapper function around fifo8_peekpop_buf() that allows the caller to
peek into FIFO, including handling the case where there is a wraparound of the
internal FIFO buffer.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
---
include/qemu/fifo8.h | 14 ++++++++++++++
util/fifo8.c | 5 +++++
2 files changed, 19 insertions(+)
diff --git a/include/qemu/fifo8.h b/include/qemu/fifo8.h
index d1d06754d8..d09984b146 100644
--- a/include/qemu/fifo8.h
+++ b/include/qemu/fifo8.h
@@ -76,6 +76,20 @@ uint8_t fifo8_pop(Fifo8 *fifo);
*/
uint32_t fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen);
+/**
+ * fifo8_peek_buf:
+ * @fifo: FIFO to read from
+ * @dest: the buffer to write the data into (can be NULL)
+ * @destlen: size of @dest and maximum number of bytes to peek
+ *
+ * Peek a number of elements from the FIFO up to a maximum of @destlen.
+ * The peeked data is copied into the @dest buffer.
+ * Care is taken when the data wraps around in the ring buffer.
+ *
+ * Returns: number of bytes peeked.
+ */
+uint32_t fifo8_peek_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen);
+
/**
* fifo8_pop_bufptr:
* @fifo: FIFO to pop from
diff --git a/util/fifo8.c b/util/fifo8.c
index 1031ffbe7e..a8f5cea158 100644
--- a/util/fifo8.c
+++ b/util/fifo8.c
@@ -140,6 +140,11 @@ uint32_t fifo8_pop_buf(Fifo8 *fifo, uint8_t *dest,
uint32_t destlen)
return fifo8_peekpop_buf(fifo, dest, destlen, true);
}
+uint32_t fifo8_peek_buf(Fifo8 *fifo, uint8_t *dest, uint32_t destlen)
+{
+ return fifo8_peekpop_buf(fifo, dest, destlen, false);
+}
+
void fifo8_drop(Fifo8 *fifo, uint32_t len)
{
len -= fifo8_pop_buf(fifo, NULL, len);
--
2.39.2
