Formatting and comment nits

1 files changed, 37 insertions, 23 deletions

diff --git a/kconfiglib.py b/kconfiglib.py
index 05cc172..afc57cb 100644
--- a/kconfiglib.py
+++ b/kconfiglib.py
@@ -829,23 +829,27 @@ class Kconfig(object):
     def write_autoconf(self, filename,
                        header="/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"):
         r"""
-        Writes out symbol values as a C header file.
+        Writes out symbol values as a C header file, matching the format used
+        by include/generated/autoconf.h in the kernel (though possibly with a
+        different ordering of the #defines, as the order in the C
+        implementation depends on the hash table implementation as of writing).
 
         filename:
           Self-explanatory.
 
         header (default: "/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"):
           Text that will be inserted verbatim at the beginning of the file. You
-          would usually want it enclosed in "/* */" to make it a C comment,
+          would usually want it enclosed in '/* */' to make it a C comment,
           and include a final terminating newline.
         """
         with open(filename, "w") as f:
 
             # Small optimization
             write = f.write
+
             write(header)
 
-            # Avoid duplicates
+            # Avoid duplicates -- see write_config()
             for sym in self.defined_syms:
                 sym._written = False
 
@@ -856,31 +860,41 @@ class Kconfig(object):
 
             while 1:
                 item = node.item
-                if isinstance(item, Symbol):
-                    if not item._written:
-                        # Force caculation of the value by means of the hidden
-                        # call triggered by accessing str_value
-                        val = item.str_value
-                        if item._write_to_conf:
-                            if item.orig_type in (BOOL, TRISTATE) and val != "n":
-                                suffix = "_MODULE" if val == "m" else ""
+                if isinstance(item, Symbol) and not item._written:
+                    # Note: _write_to_conf is determined when the value is
+                    # calculated. This is a hidden function call due to
+                    # property magic.
+                    val = item.str_value
+                    if item._write_to_conf:
+                        if item.orig_type in (BOOL, TRISTATE):
+                            if val != "n":
                                 write("#define {}{}{} 1\n"
                                       .format(self.config_prefix, item.name,
-                                              suffix))
-                            elif item.orig_type == STRING:
-                                write('#define {}{} "{}"\n'
-                                      .format(self.config_prefix, item.name,
-                                              escape(val)))
-                            elif item.orig_type in (INT, HEX):
-                                if item.orig_type == HEX and not val.startswith(("0x", "0X")):
-                                        val = "0x" + val
-                                write("#define {}{} {}\n"
-                                      .format(self.config_prefix, item.name,
-                                              val))
+                                              "_MODULE" if val == "m" else ""))
 
-                        item._written = True
+                        elif item.orig_type == STRING:
+                            write('#define {}{} "{}"\n'
+                                  .format(self.config_prefix, item.name,
+                                          escape(val)))
+
+                        elif item.orig_type in (INT, HEX):
+                            if item.orig_type == HEX and \
+                               not val.startswith(("0x", "0X")):
+                                val = "0x" + val
+
+                            write("#define {}{} {}\n"
+                                  .format(self.config_prefix, item.name,
+                                          val))
+
+                        else:
+                            _internal_error("Internal error while creating C "
+                                            'header: unknown type "{}".'
+                                            .format(item.orig_type))
+
+                    item._written = True
 
                 # Iterative tree walk using parent pointers
+
                 if node.list:
                     node = node.list
                 elif node.next: