Move config to own dir

I also broke the config header template into it's own file. Further, I
fixed a bug in the config header generation where if no macros, builds
would crash.

tools/config/__init__.py

@@ -17,10 +17,13 @@ limitations under the License.
 
 from copy import deepcopy
 import os
+from os.path import dirname, abspath
 import sys
 from collections import namedtuple
 from os.path import splitext
 from intelhex import IntelHex
+from jinja2 import FileSystemLoader, StrictUndefined
+from jinja2.environment import Environment
 # Implementation of mbed configuration mechanism
 from tools.utils import json_file_to_dict, intelhex_offset
 from tools.arm_pack_manager import Cache
@@ -852,57 +855,25 @@ class Config(object):
                  WARNING: if 'fname' names an existing file, it will be
                  overwritten!
         """
-        params, macros = config[0], config[1]
+        params, macros = config[0] or {}, config[1] or {}
         Config._check_required_parameters(params)
-        header_data = "// Automatically generated configuration file.\n"
-        header_data += "// DO NOT EDIT, content will be overwritten.\n\n"
-        header_data += "#ifndef __MBED_CONFIG_DATA__\n"
-        header_data += "#define __MBED_CONFIG_DATA__\n\n"
-        # Compute maximum length of macro names for proper alignment
-        max_param_macro_name_len = (max([len(m.macro_name) for m
-                                         in params.values()
-                                         if m.value is not None])
-                                    if params else 0)
-        max_direct_macro_name_len = (max([len(m.macro_name) for m
-                                         in macros.values()])
-                                     if macros else 0)
-        max_macro_name_len = max(max_param_macro_name_len,
-                                 max_direct_macro_name_len)
-        # Compute maximum length of macro values for proper alignment
-        max_param_macro_val_len = (max([len(str(m.value)) for m
-                                       in params.values()
-                                       if m.value is not None])
-                                   if params else 0)
-        max_direct_macro_val_len = max([len(m.macro_value or "") for m
-                                        in macros.values()]) if macros else 0
-        max_macro_val_len = max(max_param_macro_val_len,
-                                max_direct_macro_val_len)
-        # Generate config parameters first
-        if params:
-            header_data += "// Configuration parameters\n"
-            for macro in params.values():
-                if macro.value is not None:
-                    header_data += ("#define {0:<{1}} {2!s:<{3}} " +
-                                    "// set by {4}\n")\
-                        .format(macro.macro_name, max_macro_name_len,
-                                macro.value, max_macro_val_len, macro.set_by)
-        # Then macros
-        if macros:
-            header_data += "// Macros\n"
-            for macro in macros.values():
-                if macro.macro_value:
-                    header_data += ("#define {0:<{1}} {2!s:<{3}}" +
-                                    " // defined by {4}\n")\
-                        .format(macro.macro_name, max_macro_name_len,
-                                macro.macro_value, max_macro_val_len,
-                                macro.defined_by)
-                else:
-                    header_data += ("#define {0:<{1}}" +
-                                    " // defined by {2}\n")\
-                        .format(macro.macro_name,
-                                max_macro_name_len + max_macro_val_len + 1,
-                                macro.defined_by)
-        header_data += "\n#endif\n"
+        params_with_values = [p for p in params.values() if p.value is not None]
+        ctx = {
+            "cfg_params" : [(p.macro_name, str(p.value), p.set_by)
+                            for p in params_with_values],
+            "macros": [(m.macro_name, str(m.macro_value or ""), m.defined_by)
+                       for m in macros.values()],
+            "name_len":  max([len(m.macro_name) for m in macros.values()] +
+                             [len(m.macro_name) for m in params_with_values]
+                             + [0]),
+            "val_len" : max([len(str(m.value)) for m in params_with_values] +
+                            [len(m.macro_value or "") for m in macros.values()]
+                            + [0]),
+        }
+        jinja_loader = FileSystemLoader(dirname(abspath(__file__)))
+        jinja_environment = Environment(loader=jinja_loader,
+                                        undefined=StrictUndefined)
+        header_data = jinja_environment.get_template("header.tmpl").render(ctx)
         # If fname is given, write "header_data" to it
         if fname:
             with open(fname, "w+") as file_desc:

tools/config/header.tmpl

@@ -0,0 +1,26 @@
+// Automatically generated configuration file.
+// DO NOT EDIT, content will be overwritten.
+
+#ifndef __MBED_CONFIG_DATA__
+#define __MBED_CONFIG_DATA__
+
+{% if cfg_params -%}
+// Configuration parameters
+{% for name, value, set_by in cfg_params -%}
+{% if value is not none -%}
+#define {{name.ljust(name_len)}} {{value.ljust(val_len)}} // set by {{set_by}}
+{%- endif %}
+{% endfor %}
+{%- endif -%}
+
+{%- if macros -%}
+// Macros
+{% for name, value, set_by in macros -%}
+{% if value is not none -%}
+#define {{name.ljust(name_len)}} {{value.ljust(val_len)}} // defined by {{set_by}}
+{%- else -%}
+#define {{name.ljust(name_len + val_len + 1)}} // defined by {{set_by}}
+{%- endif %}
+{% endfor %}
+{%- endif %}
+#endif