[RFC PATCH 2/2] net: ifup: have ifup -a stop at the first interface

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

The normal use case for ifup -a is to get *some* interface working and
not really wait for all interfaces to come up and then timeout waiting
for those without link up to get their DHCP lease. Thus repurpose ifup
-a to mean bring up all interfaces until first success with the new
ifup -A restoring the old behavior.

The optimal action would be to make dhcp() non-blocking, but that would
be somewhat more involved.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 include/net.h |  1 +
 net/ifup.c    | 21 ++++++++++++++++-----
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/include/net.h b/include/net.h
index fdd21481dbf5..1046d1bf3681 100644
--- a/include/net.h
+++ b/include/net.h
@@ -512,6 +512,7 @@ int net_icmp_send(struct net_connection *con, int len);
 void led_trigger_network(enum led_trigger trigger);
 
 #define IFUP_FLAG_FORCE		(1 << 0)
+#define IFUP_FLAG_UNTIL_FIRST	(1 << 1)
 
 int ifup_edev(struct eth_device *edev, unsigned flags);
 int ifup(const char *name, unsigned flags);
diff --git a/net/ifup.c b/net/ifup.c
index a0167eeb8a82..1ae7dad76b87 100644
--- a/net/ifup.c
+++ b/net/ifup.c
@@ -291,11 +291,17 @@ int ifup_all(unsigned flags)
 			continue;
 
 		ifup_edev(edev, flags);
+		if ((flags & IFUP_FLAG_UNTIL_FIRST) && edev->ifup)
+			return 0;
 	}
 
-	for_each_netdev(edev)
+	for_each_netdev(edev) {
 		ifup_edev(edev, flags);
 
+		if ((flags & IFUP_FLAG_UNTIL_FIRST) && edev->ifup)
+			return 0;
+	}
+
 	return 0;
 }
 
@@ -326,12 +332,15 @@ static int do_ifup(int argc, char *argv[])
 	unsigned flags = 0;
 	int all = 0;
 
-	while ((opt = getopt(argc, argv, "af")) > 0) {
+	while ((opt = getopt(argc, argv, "aAf")) > 0) {
 		switch (opt) {
 		case 'f':
 			flags |= IFUP_FLAG_FORCE;
 			break;
 		case 'a':
+			flags |= IFUP_FLAG_UNTIL_FIRST;
+			fallthrough;
+		case 'A':
 			all = 1;
 			break;
 		}
@@ -353,14 +362,15 @@ BAREBOX_CMD_HELP_TEXT("Network interfaces are configured with a NV variables or
 BAREBOX_CMD_HELP_TEXT("/env/network/<intf> file. See Documentation/user/networking.rst")
 BAREBOX_CMD_HELP_TEXT("")
 BAREBOX_CMD_HELP_TEXT("Options:")
-BAREBOX_CMD_HELP_OPT ("-a",  "bring up all interfaces")
+BAREBOX_CMD_HELP_OPT ("-A",  "bring up all interfaces")
+BAREBOX_CMD_HELP_OPT ("-a",  "bring up all interfaces until first successful one")
 BAREBOX_CMD_HELP_OPT ("-f",  "Force. Configure even if ip already set")
 BAREBOX_CMD_HELP_END
 
 BAREBOX_CMD_START(ifup)
 	.cmd		= do_ifup,
 	BAREBOX_CMD_DESC("bring a network interface up")
-	BAREBOX_CMD_OPTS("[-af] [INTF]")
+	BAREBOX_CMD_OPTS("[-aAf] [INTF]")
 	BAREBOX_CMD_GROUP(CMD_GRP_NET)
 	BAREBOX_CMD_COMPLETE(eth_complete)
 	BAREBOX_CMD_HELP(cmd_ifup_help)
@@ -371,8 +381,9 @@ static int do_ifdown(int argc, char *argv[])
 	int opt;
 	int all = 0;
 
-	while ((opt = getopt(argc, argv, "a")) > 0) {
+	while ((opt = getopt(argc, argv, "aA")) > 0) {
 		switch (opt) {
+		case 'A':
 		case 'a':
 			all = 1;
 			break;
-- 
2.30.2