libusbg: print leading zero for MAC address bytes

The ethernet gadget driver requires the hex formatted MAC address
bytes with leading zero, in other words each byte needs to be two
characters in length (see get_ether_addr in u_ether.c). The libc
implementation ether_ntoa does not print leading zeros. Hence use
our own implementation which provides the format expected by the
kernel.

Signed-off-by: Stefan Agner <stefan@agner.ch>

Rebased onto current master.

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>

3 files changed, 17 insertions, 6 deletions

diff --git a/include/usbg/usbg_internal.h b/include/usbg/usbg_internal.h
index 30098c9..30d3fcf 100644
--- a/include/usbg/usbg_internal.h
+++ b/include/usbg/usbg_internal.h
@@ -168,5 +168,7 @@ static inline int file_select(const struct dirent *dent)
 
 int usbg_translate_error(int error);
 
+char *usbg_ether_ntoa_r(const struct ether_addr *addr, char *buf);
+
 #endif /* USBG_INTERNAL_H */
 
diff --git a/src/usbg.c b/src/usbg.c
index d8b00c9..6239c60 100644
--- a/src/usbg.c
+++ b/src/usbg.c
@@ -852,6 +852,15 @@ static int usbg_rm_all_dirs(const char *path)
 	return ret;
 }
 
+char *usbg_ether_ntoa_r(const struct ether_addr *addr, char *buf)
+{
+	sprintf(buf, "%02x:%02x:%02x:%02x:%02x:%02x",
+		addr->ether_addr_octet[0], addr->ether_addr_octet[1],
+		addr->ether_addr_octet[2], addr->ether_addr_octet[3],
+		addr->ether_addr_octet[4], addr->ether_addr_octet[5]);
+	return buf;
+}
+
 static int usbg_parse_function_net_attrs(usbg_function *f,
 		usbg_f_net_attrs *f_net_attrs)
 {
@@ -2928,12 +2937,12 @@ int usbg_set_function_net_attrs(usbg_function *f, const usbg_f_net_attrs *attrs)
 		goto out;
 	}
 
-	addr = ether_ntoa_r(&attrs->dev_addr, addr_buf);
+	addr = usbg_ether_ntoa_r(&attrs->dev_addr, addr_buf);
 	ret = usbg_write_string(f->path, f->name, "dev_addr", addr);
 	if (ret != USBG_SUCCESS)
 		goto out;
 
-	addr = ether_ntoa_r(&attrs->host_addr, addr_buf);
+	addr = usbg_ether_ntoa_r(&attrs->host_addr, addr_buf);
 	ret = usbg_write_string(f->path, f->name, "host_addr", addr);
 	if (ret != USBG_SUCCESS)
 		goto out;
@@ -3171,7 +3180,7 @@ int usbg_set_net_dev_addr(usbg_function *f, struct ether_addr *dev_addr)
 
 	if (f && dev_addr) {
 		char str_buf[USBG_MAX_STR_LENGTH];
-		char *str_addr = ether_ntoa_r(dev_addr, str_buf);
+		char *str_addr = usbg_ether_ntoa_r(dev_addr, str_buf);
 		ret = usbg_write_string(f->path, f->name, "dev_addr", str_addr);
 	} else {
 		ret = USBG_ERROR_INVALID_PARAM;
@@ -3186,7 +3195,7 @@ int usbg_set_net_host_addr(usbg_function *f, struct ether_addr *host_addr)
 
 	if (f && host_addr) {
 		char str_buf[USBG_MAX_STR_LENGTH];
-		char *str_addr = ether_ntoa_r(host_addr, str_buf);
+		char *str_addr = usbg_ether_ntoa_r(host_addr, str_buf);
 		ret = usbg_write_string(f->path, f->name, "host_addr", str_addr);
 	} else {
 		ret = USBG_ERROR_INVALID_PARAM;
diff --git a/src/usbg_schemes_libconfig.c b/src/usbg_schemes_libconfig.c
index 212fc2d..1cbf3c4 100644
--- a/src/usbg_schemes_libconfig.c
+++ b/src/usbg_schemes_libconfig.c
@@ -326,7 +326,7 @@ static int usbg_export_f_net_attrs(usbg_f_net_attrs *attrs,
 	if (!node)
 		goto out;
 
-	addr = ether_ntoa_r(&attrs->dev_addr, addr_buf);
+	addr = usbg_ether_ntoa_r(&attrs->dev_addr, addr_buf);
 	cfg_ret = config_setting_set_string(node, addr);
 	if (cfg_ret != CONFIG_TRUE) {
 		ret = USBG_ERROR_OTHER_ERROR;
@@ -337,7 +337,7 @@ static int usbg_export_f_net_attrs(usbg_f_net_attrs *attrs,
 	if (!node)
 		goto out;
 
-	addr = ether_ntoa_r(&attrs->host_addr, addr_buf);
+	addr = usbg_ether_ntoa_r(&attrs->host_addr, addr_buf);
 	cfg_ret = config_setting_set_string(node, addr);
 	if (cfg_ret != CONFIG_TRUE) {
 		ret = USBG_ERROR_OTHER_ERROR;