[U-Boot] [PATCH 02/14] net: cosmetic: Make the MAC address string less magical

[Olliver Schinagl]

In u-boot printf has been extended with the %pM formatter to allow
printing of MAC addresses. However buffers that want to store a MAC
address cannot safely get the size. Add a define for this case so the
string of a MAC address can be reliably obtained.

Signed-off-by: Olliver Schinagl <oliver at schinagl.nl>
---
 include/net.h    | 5 +++++
 net/eth_common.c | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/net.h b/include/net.h
index 8137cf3..af0558d 100644
--- a/include/net.h
+++ b/include/net.h
@@ -40,6 +40,11 @@
 
 /* ARP hardware address length */
 #define ARP_HLEN 6
+/*
+ * The size of a MAC address in string form, each digit requires two chars
+ * and five separator characters to form '00:00:00:00:00:00'.
+ */
+#define ARP_HLEN_ASCII (ARP_HLEN * 2) + (ARP_HLEN - 1)
 
 /* IPv4 addresses are always 32 bits in size */
 struct in_addr {
diff --git a/net/eth_common.c b/net/eth_common.c
index 2880901..e9d3c66 100644
--- a/net/eth_common.c
+++ b/net/eth_common.c
@@ -32,7 +32,7 @@ int eth_getenv_enetaddr(const char *name, uchar *enetaddr)
 
 int eth_setenv_enetaddr(const char *name, const uchar *enetaddr)
 {
-	char buf[20];
+	char buf[ARP_HLEN_ASCII + 1];
 
 	sprintf(buf, "%pM", enetaddr);
 
-- 
2.10.2