fix 'jtag interface' behavior

Without this patch, running "openocd -c 'jtag interface'" segfaults.
Now, it returns the string "undefined" when the interface is unset.

diff --git a/src/jtag/tcl.c b/src/jtag/tcl.c
index 71efc8b5d3d8dbd149cee63a31a6eedf6787fd64..b86e006abd175af7afec7da1e79ddc73819c7b73 100644 (file)
--- a/src/jtag/tcl.c
+++ b/src/jtag/tcl.c
@@ -422,7 +422,8 @@ static int jim_jtag_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
                        Jim_WrongNumArgs(goi.interp, 1, goi.argv-1, "(no params)");
                        return JIM_ERR;
                }
-               Jim_SetResultString(goi.interp, jtag_interface->name, -1);
+               const char *name = jtag_interface ? jtag_interface->name : NULL;
+               Jim_SetResultString(goi.interp, name ? : "undefined", -1);
                return JIM_OK;
        case JTAG_CMD_INIT:
                if (goi.argc != 0) {