Rewriting option parser wrapper to ensure memory is not lost.

The option parser wrapper allocated memory in an incorrect way, which
could lead to problems especially with --xml-output, since it would
access the memory at a later point in the execution. This could then
propagate to GUI problems, since the GUI uses the --xml-output switch.
Rewrote the code to be more readable and less incorrect.

src/switches.c

@@ -1617,74 +1617,60 @@ switcher (const int process, int index, int commandline)
  * This is a public function. It is used for the environment variables but also for the in-specification defines.
  */
 void
-process_switch_buffer (char *buf)
+process_switch_buffer (char *args_source)
 {
-  if (buf != NULL)
-    {
-      int slen;
+  int arg_string_len;
 
-      slen = strlen (buf);
-      if (slen > 0)
+  if (args_source == NULL)
+    {
+      return;
+    }
+
+  arg_string_len = strlen (args_source);
+  if (arg_string_len > 0)
     {
 	/**
-	   * We scan the buf here, but assume a stupid upper limit of 100 pieces, otherwise this all becomes fairly vague.
+	* We scan the args_source here, but assume a stupid upper limit of 100 pieces, otherwise this all becomes fairly vague.
 	*/
-	  int max = 100;
-	  char *argv[100];
-	  int count;
-	  char *args;
+      int max_args = 100;
+      char **args_array;
+      int args_count;
+      char *args_copy;
       char *scanflag;
-	  char *argn;
-
-	  /* make a safe copy */
-	  args = (char *) malloc (slen + 1);
-	  memcpy (args, buf, slen + 1);
-
-	  /* warning */
-	  /*
-	     globalError++;
-	     eprintf ("warning: using environment variable SVNSCYTHER ('%s')\n",
-	     args);
-	     globalError--;
-	   */
-
-	  {
+      char *next_arg;
       int i;
 
-	    i = 0;
-	    while (i < max)
+      /* make a safe copy */
+      args_array = malloc (sizeof (char *) * max_args);
+      args_copy = (char *) malloc (arg_string_len + 1);
+      memcpy (args_copy, args_source, arg_string_len + 1);
+
+      for (i = 0; i < max_args; i++)
 	{
-		argv[i] = "";
-		i++;
-	      }
+	  args_array[i] = "";
 	}
 
-	  scanflag = args;
-	  count = 0;
+      scanflag = args_copy;
+      args_count = 0;
       /* ugly use of assignment in condition */
-	  while (count < max)
+      while (args_count < (max_args - 1))
 	{
-	      argn = strtok (scanflag, "\t ");
-	      scanflag = NULL;
-	      if (argn != NULL)
+	  next_arg = strtok (scanflag, "\t ");
+	  scanflag = NULL;	// needed for strtok() to work properly
+	  if (next_arg != NULL)
 	    {
-		  count++;
-		  argv[count] = argn;
+	      args_count++;
+	      args_array[args_count] = next_arg;
 	    }
 	  else
 	    {
 	      break;
 	    }
 	}
-	  /*
-	     warning ("found %i arguments in SCYTHERFLAGS\n", count);
-	   */
-
-	  switches.argc = count + 1;
-	  switches.argv = argv;
+      switches.argc = args_count + 1;
+      switches.argv = args_array;
       process_switches (false);
     }
-    }
 }
 
 //! Process environment