Add oldaskconfig the default conf program

README.rst

@@ -95,6 +95,8 @@ available in the C tools.
 
 - `guiconfig <https://github.com/ulfalizer/Kconfiglib/blob/master/guiconfig.py>`_
 
+- `oldaskconfig <https://github.com/ulfalizer/Kconfiglib/blob/master/oldaskconfig.py>`_
+
 - `oldconfig <https://github.com/ulfalizer/Kconfiglib/blob/master/oldconfig.py>`_
 
 - `olddefconfig <https://github.com/ulfalizer/Kconfiglib/blob/master/olddefconfig.py>`_
@@ -214,6 +216,7 @@ Getting started
 
 5. To update an old ``.config`` file after the Kconfig files have changed (e.g.
    to add new options), run ``oldconfig`` (prompts for values for new options)
+   or ``oldaskconfig`` (shows all options with any old value as the default)
    or ``olddefconfig`` (gives new options their default value). Entering the
    ``menuconfig`` or ``guiconfig`` interface and saving the configuration will
    also update it (the configuration interfaces always prompt for saving

oldaskconfig.py

@@ -0,0 +1,248 @@
+#!/usr/bin/env python3
+
+# Copyright (c) 2018-2019, Ulf Magnusson
+# SPDX-License-Identifier: ISC
+
+"""
+Implements oldaskconfig functionality.
+
+  1. Loads existing .config
+  2. Prompts for the value of all modifiable symbols/choices
+  3. Writes an updated .config
+
+The default input/output filename is '.config'. A different filename can be
+passed in the KCONFIG_CONFIG environment variable.
+
+When overwriting a configuration file, the old version is saved to
+<filename>.old (e.g. .config.old).
+
+Entering '?' displays the help text of the symbol/choice, if any.
+
+Unlike 'make oldconfig', this script doesn't print menu titles and comments,
+but gives Kconfig definition locations. Printing menus and comments would be
+pretty easy to add: Look at the parents of each item, and print all menu
+prompts and comments unless they have already been printed (assuming you want
+to skip "irrelevant" menus).
+"""
+from __future__ import print_function
+
+import sys
+
+from kconfiglib import Symbol, Choice, BOOL, TRISTATE, HEX, standard_kconfig
+
+
+# Python 2/3 compatibility hack
+if sys.version_info[0] < 3:
+    input = raw_input
+
+
+def _main():
+    # Earlier symbols in Kconfig files might depend on later symbols and become
+    # visible if their values change. This flag is set to True if the value of
+    # any symbol changes, in which case we rerun the oldconfig to check for new
+    # visible symbols.
+    global conf_changed
+
+    kconf = standard_kconfig(__doc__)
+    print(kconf.load_config())
+
+    while True:
+        conf_changed = False
+
+        for node in kconf.node_iter():
+            oldaskconfig(node)
+
+        if not conf_changed:
+            break
+
+    print(kconf.write_config())
+
+
+def oldaskconfig(node):
+    """
+    Prompts the user for a value if node.item is a visible symbol/choice
+    """
+    # See main()
+    global conf_changed
+
+    # Only symbols and choices can be configured
+    if not isinstance(node.item, (Symbol, Choice)):
+        return
+
+    # Skip symbols and choices that aren't visible
+    if not node.item.visibility:
+        return
+
+    # Skip symbols and choices that don't have a prompt (at this location)
+    if not node.prompt:
+        return
+
+    if isinstance(node.item, Symbol):
+        sym = node.item
+
+        new = sym.user_value is None
+
+        # Skip symbols that can only have a single value, due to selects
+        if len(sym.assignable) == 1:
+            return
+
+        # Skip symbols in choices in y mode. We ask once for the entire choice
+        # instead.
+        if sym.choice and sym.choice.tri_value == 2:
+            return
+
+        # Loop until the user enters a valid value or enters a blank string
+        # (for the default value)
+        while True:
+            val = input("{} ({}) [{}]{} ".format(
+                node.prompt[0], _name_and_loc_str(sym),
+                _default_value_str(sym), _new_value_str(new)))
+
+            if val == "?":
+                _print_help(node)
+                continue
+
+            # Substitute a blank string with the default value the symbol
+            # would get
+            if not val:
+                val = sym.str_value
+
+            # Automatically add a "0x" prefix for hex symbols, like the
+            # menuconfig interface does. This isn't done when loading .config
+            # files, hence why set_value() doesn't do it automatically.
+            if sym.type == HEX and not val.startswith(("0x", "0X")):
+                val = "0x" + val
+
+            old_str_val = sym.str_value
+
+            # Kconfiglib itself will print a warning here if the value
+            # is invalid, so we don't need to bother
+            if sym.set_value(val):
+                # Valid value input. We're done with this node.
+
+                if sym.str_value != old_str_val:
+                    conf_changed = True
+
+                return
+
+    else:
+        choice = node.item
+
+        # Skip choices that already have a visible user selection...
+        if choice.user_selection and choice.user_selection.visibility == 2:
+            # ...unless there are new visible symbols in the choice. (We know
+            # they have y (2) visibility in that case, because m-visible
+            # symbols get demoted to n-visibility in y-mode choices, and the
+            # user-selected symbol had visibility y.)
+            for sym in choice.syms:
+                if sym is not choice.user_selection and sym.visibility and \
+                   sym.user_value is None:
+                    # New visible symbols in the choice
+                    break
+            else:
+                # No new visible symbols in the choice
+                return
+
+        # Get a list of available selections. The mode of the choice limits
+        # the visibility of the choice value symbols, so this will indirectly
+        # skip choices in n and m mode.
+        options = [sym for sym in choice.syms if sym.visibility == 2]
+
+        if not options:
+            # No y-visible choice value symbols
+            return
+
+        # Loop until the user enters a valid selection or a blank string (for
+        # the default selection)
+        while True:
+            print("{} ({})".format(node.prompt[0], _name_and_loc_str(choice)))
+
+            for i, sym in enumerate(options, 1):
+                print("{} {}. {} ({})".format(
+                    ">" if sym is choice.selection else " ",
+                    i,
+                    # Assume people don't define choice symbols with multiple
+                    # prompts. That generates a warning anyway.
+                    sym.nodes[0].prompt[0],
+                    sym.name))
+
+            sel_index = input("choice[1-{}]: ".format(len(options)))
+
+            if sel_index == "?":
+                _print_help(node)
+                continue
+
+            # Pick the default selection if the string is blank
+            if not sel_index:
+                choice.selection.set_value(2)
+                break
+
+            try:
+                sel_index = int(sel_index)
+            except ValueError:
+                print("Bad index", file=sys.stderr)
+                continue
+
+            if not 1 <= sel_index <= len(options):
+                print("Bad index", file=sys.stderr)
+                continue
+
+            # Valid selection
+
+            if options[sel_index - 1].tri_value != 2:
+                conf_changed = True
+
+            options[sel_index - 1].set_value(2)
+            break
+
+        # Give all of the non-selected visible choice symbols the user value n.
+        # This makes it so that the choice is no longer considered new once we
+        # do additional passes, if the reason that it was considered new was
+        # that it had new visible choice symbols.
+        #
+        # Only giving visible choice symbols the user value n means we will
+        # prompt for the choice again if later user selections make more new
+        # choice symbols visible, which is correct.
+        for sym in choice.syms:
+            if sym is not choice.user_selection and sym.visibility:
+                sym.set_value(0)
+
+
+def _name_and_loc_str(sc):
+    # Helper for printing the name of the symbol/choice 'sc' along with the
+    # location(s) in the Kconfig files where it is defined. Unnamed choices
+    # return "choice" instead of the name.
+
+    return "{}, defined at {}".format(
+        sc.name or "choice",
+        ", ".join("{}:{}".format(node.filename, node.linenr)
+                  for node in sc.nodes))
+
+
+def _print_help(node):
+    print("\n" + (node.help or "No help text\n"))
+
+
+def _default_value_str(sym):
+    # Returns the "m/M/y" string in e.g.
+    #
+    #   TRISTATE_SYM prompt (TRISTATE_SYM, defined at Kconfig:9) [n/M/y]:
+    #
+    # For string/int/hex, returns the default value as-is.
+
+    if sym.type in (BOOL, TRISTATE):
+        return "/".join(("NMY" if sym.tri_value == tri else "nmy")[tri]
+                        for tri in sym.assignable)
+
+    # string/int/hex
+    return sym.str_value
+
+
+def _new_value_str(new):
+    if new:
+        return " (NEW)"
+    return ""
+
+
+if __name__ == "__main__":
+    _main()

setup.py

@@ -31,6 +31,7 @@
         "menuconfig",
         "guiconfig",
         "genconfig",
+        "oldaskconfig",
         "oldconfig",
         "olddefconfig",
         "savedefconfig",
@@ -48,6 +49,7 @@
             "menuconfig = menuconfig:_main",
             "guiconfig = guiconfig:_main",
             "genconfig = genconfig:main",
+            "oldaskconfig = oldaskconfig:_main",
             "oldconfig = oldconfig:_main",
             "olddefconfig = olddefconfig:main",
             "savedefconfig = savedefconfig:main",