dhcpd: Supports kernel mode compilation

The previous method of terminating the dhcp daemon via a global variable has been removed; instead, the `kill pid` command is used. Also, because the original `dhcp_start` method creates tasks via `task_create`, which is not supported in kernel mode, `dhcp_start` is not compiled in kernel mode. The daemon can be started in kernel mode using `dhcpd xxx &`.

Signed-off-by: zhangshuai39 <zhangshuai39@xiaomi.com>

examples/dhcpd/CMakeLists.txt

@@ -30,23 +30,27 @@ if(CONFIG_EXAMPLES_DHCPD)
     STACKSIZE
     ${CONFIG_DEFAULT_TASK_STACKSIZE})
 
-  nuttx_add_application(
-    NAME
-    dhcpd_start
-    SRCS
-    dhcpd_start.c
-    dhcpd_daemon.c
-    STACKSIZE
-    ${CONFIG_DEFAULT_TASK_STACKSIZE})
+  if(NOT CONFIG_BUILD_KERNEL)
+    nuttx_add_application(
+      NAME
+      dhcpd_start
+      SRCS
+      dhcpd_start.c
+      dhcpd_daemon.c
+      STACKSIZE
+      ${CONFIG_DEFAULT_TASK_STACKSIZE})
+  endif()
 
-  nuttx_add_application(
-    NAME
-    dhcpd_stop
-    SRCS
-    dhcpd_stop.c
-    dhcpd_daemon.c
-    STACKSIZE
-    ${CONFIG_DEFAULT_TASK_STACKSIZE})
+  if(CONFIG_SCHED_WAITPID)
+    nuttx_add_application(
+      NAME
+      dhcpd_stop
+      SRCS
+      dhcpd_stop.c
+      dhcpd_daemon.c
+      STACKSIZE
+      ${CONFIG_DEFAULT_TASK_STACKSIZE})
+  endif()
 
   add_definitions(-DCONFIG_NETUTILS_DHCPD_HOST=1 -DHAVE_SO_REUSEADDR=1
                   -DHAVE_SO_BROADCAST=1)

examples/dhcpd/Makefile

@@ -26,13 +26,23 @@ include $(APPDIR)/Make.defs
 
 CSRCS = dhcpd_daemon.c
 
-MAINSRC = dhcpd_start.c dhcpd_stop.c target.c
+MAINSRC = target.c
 
 # DHCPD built-in application info
 
-PROGNAME = dhcpd_start dhcpd_stop dhcpd
+PROGNAME = dhcpd
 PRIORITY = SCHED_PRIORITY_DEFAULT
 STACKSIZE = $(CONFIG_DEFAULT_TASK_STACKSIZE)
 MODULE = $(CONFIG_EXAMPLES_DHCPD)
 
+ifneq ($(CONFIG_BUILD_KERNEL),y)
+MAINSRC += dhcpd_start.c
+PROGNAME += dhcpd_start
+endif
+
+ifeq ($(CONFIG_SCHED_WAITPID),y)
+MAINSRC += dhcpd_stop.c
+PROGNAME += dhcpd_stop
+endif
+
 include $(APPDIR)/Application.mk

examples/dhcpd/dhcpd_daemon.c

@@ -128,10 +128,12 @@ int dhcpd_daemon(int argc, FAR char *argv[], bool daemon)
 
   /* Then start the dhcpd */
 
-  if (daemon)
+#ifndef CONFIG_BUILD_KERNEL
+  if (!daemon)
     {
-      return dhcpd_run(devname);
+      return dhcpd_start(devname);
     }
+#endif
 
-  return dhcpd_start(devname);
+  return dhcpd_run(devname);
 }