implement reset on posix (#1882)

examples/platforms/posix/misc.c

@@ -28,12 +28,38 @@
 
 #include "platform-posix.h"
 
+#ifndef _WIN32
+#include <unistd.h>
+#endif
+
 #include <openthread/types.h>
 #include <openthread/platform/misc.h>
 
+#ifndef _WIN32
+extern int      gArgumentsCount;
+extern char   **gArguments;
+#endif
+
 void otPlatReset(otInstance *aInstance)
 {
-    // This function does nothing on the Posix platform.
+#ifndef _WIN32
+    char *argv[gArgumentsCount + 1];
+
+    for (int i = 0; i < gArgumentsCount; ++i)
+    {
+        argv[i] = gArguments[i];
+    }
+
+    argv[gArgumentsCount] = NULL;
+
+    platformUartRestore();
+
+    execvp(argv[0], argv);
+    perror("reset failed");
+    exit(EXIT_FAILURE);
+#else
+    // This function does nothing on the Windows platform.
+#endif // _WIN32
     (void)aInstance;
 }
 

examples/platforms/posix/platform-posix.h

@@ -163,4 +163,10 @@ void platformUartUpdateFdSet(fd_set *aReadFdSet, fd_set *aWriteFdSet, fd_set *aE
  */
 void platformUartProcess(void);
 
+/**
+ * This function restores the Uart.
+ *
+ */
+void platformUartRestore(void);
+
 #endif  // PLATFORM_POSIX_H_

examples/platforms/posix/platform.c

@@ -53,6 +53,11 @@
 uint32_t NODE_ID = 1;
 uint32_t WELLKNOWN_NODE_ID = 34;
 
+#ifndef _WIN32
+int     gArgumentsCount = 0;
+char  **gArguments = NULL;
+#endif
+
 void PlatformInit(int argc, char *argv[])
 {
     char *endptr;
@@ -65,6 +70,9 @@ void PlatformInit(int argc, char *argv[])
 #ifndef _WIN32
     openlog(basename(argv[0]), LOG_PID, LOG_USER);
     setlogmask(setlogmask(0) & LOG_UPTO(LOG_NOTICE));
+
+    gArgumentsCount = argc;
+    gArguments = argv;
 #endif
 
     NODE_ID = (uint32_t)strtol(argv[1], &endptr, 0);

examples/platforms/posix/uart-posix.c

@@ -69,6 +69,12 @@ static void restore_stdout_termios(void)
     tcsetattr(s_out_fd, TCSAFLUSH, &original_stdout_termios);
 }
 
+void platformUartRestore(void)
+{
+    restore_stdin_termios();
+    restore_stdout_termios();
+}
+
 otError otPlatUartEnable(void)
 {
     otError error = OT_ERROR_NONE;