[PATCHv10 09/15] net/lwip: implement ping cmd

[Maxim Uvarov]

U-Boot recently got support for an alternative network stack using LWIP.
Replace ping command with the LWIP variant while keeping the output and
error messages identical. ping uses lwIP contrib/apps/ping/ping.c code.
Custom timeout is used to get an error message on not modified example.

There is pending lwip patch:
	https://lists.nongnu.org/archive/html/lwip-devel/2023-09/msg00004.html
	https://savannah.nongnu.org/bugs/?64697
Once applied, more clean way can be used, to unset pending timers and exit
from the ping application:
	net/lwip/apps/ping/ping.h:
 #define PING_RESULT(cond) { \
..
-               raw_remove(pcb); \
+               ping_destroy(); \

Signed-off-by: Maxim Uvarov <maxim.uvarov at linaro.org>
---
 include/net/lwip.h             | 15 +++++++++++++
 net/lwip/Makefile              |  1 +
 net/lwip/apps/ping/Makefile    | 12 +++++++++++
 net/lwip/apps/ping/lwip_ping.c | 39 ++++++++++++++++++++++++++++++++++
 net/lwip/apps/ping/lwip_ping.h | 15 +++++++++++++
 net/lwip/apps/ping/ping.h      | 27 +++++++++++++++++++++++
 6 files changed, 109 insertions(+)
 create mode 100644 net/lwip/apps/ping/Makefile
 create mode 100644 net/lwip/apps/ping/lwip_ping.c
 create mode 100644 net/lwip/apps/ping/lwip_ping.h
 create mode 100644 net/lwip/apps/ping/ping.h

diff --git a/include/net/lwip.h b/include/net/lwip.h
index 85f08343fd..1e92f9871c 100644
--- a/include/net/lwip.h
+++ b/include/net/lwip.h
@@ -2,6 +2,8 @@
 
 int do_lwip_dns(struct cmd_tbl *cmdtp, int flag, int argc,
 		char *const argv[]);
+int do_lwip_ping(struct cmd_tbl *cmdtp, int flag, int argc,
+		 char *const argv[]);
 
 /**
  * ulwip_dns() - creates the DNS request to resolve a domain host name
@@ -56,3 +58,16 @@ int ulwip_tftp(ulong addr, const char *filename);
  * Returns: 0 for success, !0 if error
  */
 int ulwip_wget(ulong addr, char *url);
+
+/**
+ * ulwip_ping - create the ping request
+ *
+ * This function creates the ping for  address provided in parameters.
+ * After this function you need to invoke the polling
+ * loop to process network communication.
+ *
+ *
+ * @ping_addr: IP address to ping
+ * Returns: 0 for success, !0 if error
+*/
+int ulwip_ping(char *ping_addr);
diff --git a/net/lwip/Makefile b/net/lwip/Makefile
index 61042862e1..5839d125c2 100644
--- a/net/lwip/Makefile
+++ b/net/lwip/Makefile
@@ -67,3 +67,4 @@ obj-y += apps/dhcp/lwip-dhcp.o
 obj-y += apps/dns/lwip-dns.o
 obj-y += apps/tftp/
 obj-y += apps/http/
+obj-y += apps/ping/
diff --git a/net/lwip/apps/ping/Makefile b/net/lwip/apps/ping/Makefile
new file mode 100644
index 0000000000..e567c0dc3e
--- /dev/null
+++ b/net/lwip/apps/ping/Makefile
@@ -0,0 +1,12 @@
+ccflags-y += -I$(srctree)/net/lwip/port/include
+ccflags-y += -I$(srctree)/net/lwip/lwip-external/src/include -I$(srctree)/net/lwip
+ccflags-y += -I$(obj)
+
+# ping.c includes "ping.h", copy it to local directory, to override ping.h
+.PHONY: $(obj)/ping.c
+$(obj)/ping.o: $(obj)/ping.c
+$(obj)/ping.c:
+	cp $(srctree)/net/lwip/lwip-external/contrib/apps/ping/ping.c $(obj)/ping.c
+
+obj-y += ping.o
+obj-y += lwip_ping.o
diff --git a/net/lwip/apps/ping/lwip_ping.c b/net/lwip/apps/ping/lwip_ping.c
new file mode 100644
index 0000000000..ba02e7ed47
--- /dev/null
+++ b/net/lwip/apps/ping/lwip_ping.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * (C) Copyright 2023 Linaro Ltd. <maxim.uvarov at linaro.org>
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/timeouts.h"
+#include <linux/errno.h>
+#include "ping.h"
+#include "lwip_ping.h"
+
+#define PING_WAIT_MS 5000
+
+static ip_addr_t ip_target;
+
+void ping_tmo(void *arg)
+{
+	log_err("ping_tmo: ping failed; host %s is not alive\n",
+		ipaddr_ntoa(&ip_target));
+	ulwip_exit(1);
+}
+
+int ulwip_ping(char *ping_addr)
+{
+	int err;
+
+	err = ipaddr_aton(ping_addr, &ip_target);
+	if (!err)
+		return -ENOENT;
+
+	sys_timeout(PING_WAIT_MS, ping_tmo, NULL);
+
+	ping_init(&ip_target);
+	ping_send_now();
+
+	return 0;
+}
diff --git a/net/lwip/apps/ping/lwip_ping.h b/net/lwip/apps/ping/lwip_ping.h
new file mode 100644
index 0000000000..0374f07d9e
--- /dev/null
+++ b/net/lwip/apps/ping/lwip_ping.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+/*
+ * (C) Copyright 2023 Linaro Ltd. <maxim.uvarov at linaro.org>
+ */
+
+#ifndef LWIP_PING_H
+#define LWIP_PING_H
+
+#include <lwip/ip_addr.h>
+
+void ping_raw_init(void);
+void ping_send_now(void);
+
+#endif /* LWIP_PING_H */
diff --git a/net/lwip/apps/ping/ping.h b/net/lwip/apps/ping/ping.h
new file mode 100644
index 0000000000..5dd631f2f7
--- /dev/null
+++ b/net/lwip/apps/ping/ping.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <net/ulwip.h>
+#include "lwip/ip_addr.h"
+
+void ping_tmo(void *arg);
+
+#define LWIP_DEBUG 1 /* ping_time is under ifdef*/
+#define PING_RESULT(cond) { \
+	if (cond == 1) { \
+		printf("host %s a alive\n", ipaddr_ntoa(addr)); \
+		printf(" %"U32_F" ms\n", (sys_now() - ping_time)); \
+		raw_remove(pcb); \
+		sys_untimeout(ping_tmo, NULL); \
+		sys_check_timeouts(); \
+		ulwip_exit(0); \
+	} else { \
+		printf("ping failed; host %s in not alive\n",\
+		       ipaddr_ntoa(addr)); \
+		raw_remove(pcb); \
+		sys_untimeout(ping_tmo, NULL); \
+		sys_check_timeouts(); \
+		ulwip_exit(-1); \
+	} \
+     } while (0);
+
+void ping_init(const ip_addr_t *ping_addr);
-- 
2.30.2