gdbserver with reversed arguments goes into an infinite loop

[Denis PILAT <denis dot pilat at st dot com>]

I've found that if you revert the argument of gdbserver, means writing 
the program's name before the COMM argument, it goes into an infinite 
loop, and as the CTRL+C does not work, you have to kill the process from 
an other shell.

In gdbserver/server.c, the loop in question does the remote_open on the 
wrong passed argument (argv[1]) which unfortunately is the binary file 
you'd expect to open so remote_open does not exit on error.

I think either we could check that we pass correct argument before using 
start_inferior(), this is executing before the loop. The bellow patch is 
in that sense.

Or we find a way to exit the loop by adding a test in it. May be by 
adding something in remote_open to let it fail.


I'd like your opinion about that
Thanks
--
Denis Pilat / STMicroelectronics

Index: server.c
===================================================================
--- server.c    (revision 544)
+++ server.c    (working copy)
@@ -408,6 +408,13 @@ main (int argc, char *argv[])

  if (pid == 0)
    {
+      if (access (argv[2], F_OK) != 0)
+      {
+        fprintf (stderr, "File %s does not exist.\n",argv[2]);
+        gdbserver_usage ();
+        exit (0);
+      }
+
      /* Wait till we are at first instruction in program.  */
      signal = start_inferior (&argv[2], &status);