[RFC 1/2] udhcpc: Wait for interface to become available

[Sven Eckelmann]

From: Marek Lindner <marek.lindner at open-mesh.com>

udhcpc can fail to read the interface information when it was just created
dynamically. Instead of failing directly, udhcpc can wait 2 seconds and
retry 5 times to get data from it.

Signed-off-by: Marek Lindner <marek.lindner at open-mesh.com>
Signed-off-by: Sven Eckelmann <sven.eckelmann at open-mesh.com>
---
This is a rather old patch which was used together with OpenWrt before
netifd was used. Maybe someone still has interests in this workaround (or
in a variant of it)...
---
 networking/udhcp/dhcpc.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 1c10511..10b9e0f 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1362,11 +1362,19 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
 		udhcp_str2optset(optstr, &client_config.options);
 	}
 
-	if (udhcp_read_interface(client_config.interface,
-			&client_config.ifindex,
-			NULL,
-			client_config.client_mac)
-	) {
+	for (timeout = 0; timeout < 5; timeout++) {
+		if (!udhcp_read_interface(client_config.interface,
+				&client_config.ifindex,
+				NULL,
+				client_config.client_mac)
+		) {
+			break;
+		}
+
+		sleep(2);
+	}
+
+	if (timeout == 5) {
 		return 1;
 	}
 
-- 
2.10.2