Add rustc_cfg file to kconfig

Updat kconfiglib.py and add rustc_cfg as output to kconfig.py

Signed-off-by: Finn Behrens <me@kloenk.de>

cmake/modules/kconfig.cmake

@@ -13,6 +13,12 @@ set_ifndef(AUTOCONF_H ${PROJECT_BINARY_DIR}/include/generated/zephyr/autoconf.h)
 # Re-configure (Re-execute all CMakeLists.txt code) when autoconf.h changes
 set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${AUTOCONF_H})
 
+# rustc_cfg is generated by Kconfig and placed in
+# <build>/zephyr/include/generated/rustc_cfg.
+# A project may request a custom location by setting RUSTC_CFG explicitly before
+# calling 'find_package(Zephyr)' or loading this module.
+set_ifndef(RUSTC_CFG ${PROJECT_BINARY_DIR}/include/generated/zephyr/rustc_cfg)
+
 # Folders needed for conf/mconf files (kconfig has no method of redirecting all output files).
 # conf/mconf needs to be run from a different directory because of: GH-3408
 file(MAKE_DIRECTORY ${PROJECT_BINARY_DIR}/kconfig/include/generated)
@@ -367,6 +373,11 @@ if(NOT EXISTS ${autoconf_h_path})
   file(MAKE_DIRECTORY ${autoconf_h_path})
 endif()
 
+cmake_path(GET RUSTC_CFG PARENT_PATH rustc_cfg_path)
+if(NOT EXISTS ${rustc_cfg_path})
+  file(MAKE_DIRECTORY ${rustc_cfg_path})
+endif()
+
 execute_process(
   COMMAND ${CMAKE_COMMAND} -E env
   ${COMMON_KCONFIG_ENV_SETTINGS}
@@ -378,6 +389,7 @@ execute_process(
   ${KCONFIG_ROOT}
   ${DOTCONFIG}
   ${AUTOCONF_H}
+  ${RUSTC_CFG}
   ${PARSED_KCONFIG_SOURCES_TXT}
   ${input_configs}
   WORKING_DIRECTORY ${APPLICATION_SOURCE_DIR}

scripts/kconfig/kconfig.py

@@ -120,6 +120,7 @@ def main():
     # Write the merged configuration and the C header
     print(kconf.write_config(args.config_out))
     print(kconf.write_autoconf(args.header_out))
+    print(kconf.write_rustcfg(args.rustcfg_out))
 
     # Write the list of parsed Kconfig files to a file
     write_kconfig_filenames(kconf, args.kconfig_list_out)
@@ -302,6 +303,8 @@ def parse_args():
                         help="Output configuration file")
     parser.add_argument("header_out",
                         help="Output header file")
+    parser.add_argument("rustcfg_out",
+                        help="Output rustcfg file")
     parser.add_argument("kconfig_list_out",
                         help="Output file for list of parsed Kconfig files")
     parser.add_argument("configs_in",

scripts/kconfig/kconfiglib.py

@@ -1096,8 +1096,6 @@ def _init(self, filename, warn, warn_to_stderr, encoding):
 
         # Do various menu tree post-processing
         self._finalize_node(self.top_node, self.y)
-        for s in self.syms.values():
-            self._finalize_sym(s)
 
         self.unique_defined_syms = _ordered_unique(self.defined_syms)
         self.unique_choices = _ordered_unique(self.choices)
@@ -1419,7 +1417,7 @@ def load_allconfig(self, filename):
     def write_autoconf(self, filename=None, header=None):
         r"""
         Writes out symbol values as a C header file, matching the format used
-        by include/generated/zephyr/autoconf.h in the kernel.
+        by include/generated/autoconf.h in the kernel.
 
         The ordering of the #defines matches the one generated by
         write_config(). The order in the C implementation depends on the hash
@@ -1434,7 +1432,7 @@ def write_autoconf(self, filename=None, header=None):
           Path to write header to.
 
           If None (the default), the path in the environment variable
-          KCONFIG_AUTOHEADER is used if set, and "include/generated/zephyr/autoconf.h"
+          KCONFIG_AUTOHEADER is used if set, and "include/generated/autoconf.h"
           otherwise. This is compatible with the C tools.
 
         header (default: None):
@@ -1453,7 +1451,7 @@ def write_autoconf(self, filename=None, header=None):
         """
         if filename is None:
             filename = os.getenv("KCONFIG_AUTOHEADER",
-                                 "include/generated/zephyr/autoconf.h")
+                                 "include/generated/autoconf.h")
 
         if self._write_if_changed(filename, self._autoconf_contents(header)):
             return "Kconfig header saved to '{}'".format(filename)
@@ -1547,7 +1545,8 @@ def write_config(self, filename=None, header=None, save_old=True,
           written.
 
           Errors are silently ignored if <filename>.old cannot be written (e.g.
-          due to permissions errors).
+          due to being a directory, or <filename> being something like
+          /dev/null).
 
         verbose (default: None):
           Limited backwards compatibility to prevent crashes. A warning is
@@ -1730,6 +1729,50 @@ def _min_config_contents(self, header):
 
         return "".join(chunks)
 
+    def write_rustcfg(self, filename=None):
+        r"""
+        Write out rustcfg flags as a response file, matching the format used
+        by include/generated/rustc_cfg in the kernel.
+
+        filename (default: None):
+          Path to write respone file to.
+
+          If None (the default), the path in the environment variable
+          KCONFIG_RUSTCCFG is used if set, and "include/generated/rustc_cfg"
+          otherwise. This is compatible with the C tools.
+        """
+        if filename is None:
+            filename = os.getenv("KCONFIG_RUSTCCFG",
+                                 "include/generated/rustc_cfg")
+
+        if self._write_if_changed(filename, self._rustcfg_contents()):
+            return "Kconfig cfg saved to '{}".format(filename)
+        return "No changes to Kconfig cfg in '{}'".format(filename)
+
+    def _rustcfg_contents(self):
+        chunks = []
+        add = chunks.append
+
+        for sym in self.unique_defined_syms:
+            if not sym.choice and \
+               sym.visibility <= expr_value(sym.rev_dep):
+                continue
+
+            val = sym.str_value
+            if sym.orig_type in _BOOL_TRISTATE:
+                # We do not care about disabled ones, would be a comment
+                if val == "n":
+                    continue
+                add("--cfg={}{}\n"
+                    .format(self.config_prefix, sym.name))
+            elif sym.orig_type == HEX:
+                if not val.lower().startswith("0x"):
+                    val = "0x{}".format(val);
+            add("--cfg={}{}={}\n"
+                .format(self.config_prefix, sym.name, escape(val)))
+
+        return "".join(chunks)
+
     def sync_deps(self, path):
         """
         Creates or updates a directory structure that can be used to avoid
@@ -2307,7 +2350,6 @@ def _lookup_sym(self, name):
         sym.kconfig = self
         sym.name = name
         sym.is_constant = False
-        sym.configdefaults = []
         sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n
 
         if self._parsing_kconfigs:
@@ -2327,7 +2369,6 @@ def _lookup_const_sym(self, name):
         sym.kconfig = self
         sym.name = name
         sym.is_constant = True
-        sym.configdefaults = []
         sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n
 
         if self._parsing_kconfigs:
@@ -2917,7 +2958,7 @@ def _parse_block(self, end_token, parent, prev):
         while self._next_line():
             t0 = self._tokens[0]
 
-            if t0 in [_T_CONFIG, _T_MENUCONFIG, _T_CONFIGDEFAULT]:
+            if t0 is _T_CONFIG or t0 is _T_MENUCONFIG:
                 # The tokenizer allocates Symbol objects for us
                 sym = self._tokens[1]
 
@@ -2932,8 +2973,7 @@ def _parse_block(self, end_token, parent, prev):
                 node = MenuNode()
                 node.kconfig = self
                 node.item = sym
-                node.is_menuconfig = t0 is _T_MENUCONFIG
-                node.is_configdefault = t0 is _T_CONFIGDEFAULT
+                node.is_menuconfig = (t0 is _T_MENUCONFIG)
                 node.prompt = node.help = node.list = None
                 node.parent = parent
                 node.filename = self.filename
@@ -2944,14 +2984,6 @@ def _parse_block(self, end_token, parent, prev):
 
                 self._parse_props(node)
 
-                if node.is_configdefault:
-                    if (node.prompt or
-                            node.dep != self.y or
-                            len(node.ranges) > 0 or
-                            len(node.selects) > 0 or
-                            len(node.implies) > 0):
-                        self._parse_error("configdefault can only contain `default`")
-
                 if node.is_menuconfig and not node.prompt:
                     self._warn("the menuconfig symbol {} has no prompt"
                                .format(sym.name_and_loc))
@@ -3564,23 +3596,6 @@ def _invalidate_all(self):
     # Post-parsing menu tree processing, including dependency propagation and
     # implicit submenu creation
     #
-    def _finalize_sym(self, sym):
-        # Finalizes symbol definitions
-        #
-        #  - Applies configdefault node defaults to final symbols
-        #
-        # sym:
-        #   The symbol to finalize.
-
-        inserted = 0
-        for (idx, defaults) in sym.configdefaults:
-            for d in defaults:
-                # Add the defaults to the node, with the requirement that
-                # direct dependencies are respected. The original order
-                # of the default statements between nodes is preserved.
-                default = (d[0], self._make_and(sym.direct_dep, d[1]))
-                sym.defaults.insert(inserted + idx, default)
-                inserted += 1
 
     def _finalize_node(self, node, visible_if):
         # Finalizes a menu node and its children:
@@ -3727,14 +3742,6 @@ def _add_props_to_sym(self, node):
 
         sym = node.item
 
-        if node.is_configdefault:
-            # Store any defaults for later application after the complete tree
-            # is known. The current length of the default array is stored so
-            # the configdefaults can be inserted in the order they originally
-            # appeared.
-            sym.configdefaults.append((len(sym.defaults), node.defaults))
-            return
-
         # See the Symbol class docstring
         sym.direct_dep = self._make_or(sym.direct_dep, node.dep)
 
@@ -4287,7 +4294,6 @@ class Symbol(object):
         "_write_to_conf",
         "choice",
         "defaults",
-        "configdefaults",
         "direct_dep",
         "env_var",
         "implies",
@@ -4346,7 +4352,7 @@ def str_value(self):
         # function call (property magic)
         vis = self.visibility
 
-        self._write_to_conf = vis != 0
+        self._write_to_conf = (vis != 0)
 
         if self.orig_type in _INT_HEX:
             # The C implementation checks the user value against the range in a
@@ -4484,7 +4490,7 @@ def tri_value(self):
         # Warning: See Symbol._rec_invalidate(), and note that this is a hidden
         # function call (property magic)
         vis = self.visibility
-        self._write_to_conf = vis != 0
+        self._write_to_conf = (vis != 0)
 
         val = 0
 
@@ -5652,7 +5658,6 @@ class MenuNode(object):
         "help",
         "include_path",
         "is_menuconfig",
-        "is_configdefault",
         "item",
         "kconfig",
         "linenr",
@@ -5854,13 +5859,8 @@ def indent_add_cond(s, cond):
         sc = self.item
 
         if sc.__class__ is Symbol:
-            if self.is_menuconfig:
-                t = "menuconfig "
-            elif self.is_configdefault:
-                t = "configdefault "
-            else:
-                t = "config "
-            lines = [t + sc.name]
+            lines = [("menuconfig " if self.is_menuconfig else "config ")
+                     + sc.name]
         else:
             lines = ["choice " + sc.name if sc.name else "choice"]
 
@@ -6247,14 +6247,14 @@ def standard_kconfig(description=None):
     Exits with sys.exit() (which raises SystemExit) on errors.
 
     description (default: None):
-      The 'description' passed to argparse.ArgumentParser(allow_abbrev=False).
+      The 'description' passed to argparse.ArgumentParser().
       argparse.RawDescriptionHelpFormatter is used, so formatting is preserved.
     """
     import argparse
 
     parser = argparse.ArgumentParser(
         formatter_class=argparse.RawDescriptionHelpFormatter,
-        description=description, allow_abbrev=False)
+        description=description)
 
     parser.add_argument(
         "kconfig",
@@ -6436,12 +6436,6 @@ def _touch_dep_file(path, sym_name):
 def _save_old(path):
     # See write_config()
 
-    if not os.path.isfile(path):
-        # Backup only files (and symlinks to files). Simplest alternative
-        # to avoid e.g. (potentially successful attempt to) rename /dev/null
-        # (and to keep fifos).
-        return
-
     def copy(src, dst):
         # Import as needed, to save some startup time
         import shutil
@@ -6466,7 +6460,8 @@ def copy(src, dst):
     except Exception:
         # Ignore errors from 'path' missing as well as other errors.
         # <filename>.old file is usually more of a nice-to-have, and not worth
-        # erroring out over e.g. if <filename>.old happens to be a directory.
+        # erroring out over e.g. if <filename>.old happens to be a directory or
+        # <filename> is something like /dev/null.
         pass
 
 
@@ -6905,7 +6900,6 @@ def _shell_fn(kconf, _, command):
     _T_CLOSE_PAREN,
     _T_COMMENT,
     _T_CONFIG,
-    _T_CONFIGDEFAULT,
     _T_DEFAULT,
     _T_DEFCONFIG_LIST,
     _T_DEF_BOOL,
@@ -6949,7 +6943,7 @@ def _shell_fn(kconf, _, command):
     _T_TRISTATE,
     _T_UNEQUAL,
     _T_VISIBLE,
-) = range(1, 52)
+) = range(1, 51)
 
 # Keyword to token map, with the get() method assigned directly as a small
 # optimization
@@ -6961,7 +6955,6 @@ def _shell_fn(kconf, _, command):
     "choice":         _T_CHOICE,
     "comment":        _T_COMMENT,
     "config":         _T_CONFIG,
-    "configdefault":  _T_CONFIGDEFAULT,
     "def_bool":       _T_DEF_BOOL,
     "def_hex":        _T_DEF_HEX,
     "def_int":        _T_DEF_INT,