path: root/lib/bb/data_smart.py

# ex:ts=4:sw=4:sts=4:et
# -*- tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*-
"""
BitBake Smart Dictionary Implementation

Functions for interacting with the data structure used by the
BitBake build tools.

"""

# Copyright (C) 2003, 2004  Chris Larson
# Copyright (C) 2004, 2005  Seb Frankengul
# Copyright (C) 2005, 2006  Holger Hans Peter Freyther
# Copyright (C) 2005        Uli Luckas
# Copyright (C) 2005        ROAD GmbH
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
# Based on functions from the base bb module, Copyright 2003 Holger Schurig

import copy, re, sys
from collections import MutableMapping
import bb
from bb   import utils
from bb.COW  import COWDictBase


__setvar_keyword__ = ["_append", "_prepend"]
__setvar_regexp__ = re.compile('(?P<base>.*?)(?P<keyword>_append|_prepend)(_(?P<add>.*))?')
__expand_var_regexp__ = re.compile(r"\${[^{}]+}")
__expand_python_regexp__ = re.compile(r"\${@.+?}")


class DataSmart(MutableMapping):
    def __init__(self, special = COWDictBase.copy(), seen = COWDictBase.copy() ):
        self.dict = {}

        # cookie monster tribute
        self._special_values = special
        self._seen_overrides = seen

        self.expand_cache = {}

    def expand(self, s, varname):
        def var_sub(match):
            key = match.group()[2:-1]
            if varname and key:
                if varname == key:
                    raise Exception("variable %s references itself!" % varname)
            var = self.getVar(key, 1)
            if var is not None:
                return var
            else:
                return match.group()

        def python_sub(match):
            code = match.group()[3:-1]
            codeobj = compile(code.strip(), varname or "<expansion>", "eval")
            value = utils.better_eval(codeobj, {"d": self})
            return str(value)

        if not isinstance(s, basestring): # sanity check
            return s

        if varname and varname in self.expand_cache:
            return self.expand_cache[varname]

        while s.find('${') != -1:
            olds = s
            try:
                s = __expand_var_regexp__.sub(var_sub, s)
                s = __expand_python_regexp__.sub(python_sub, s)
                if s == olds:
                    break
            except KeyboardInterrupt:
                raise
            except:
                bb.msg.note(1, bb.msg.domain.Data, "%s:%s while evaluating:\n%s" % (sys.exc_info()[0], sys.exc_info()[1], s))
                raise

        if varname:
            self.expand_cache[varname] = s

        return s

    def finalize(self):
        """Performs final steps upon the datastore, including application of overrides"""

        overrides = (self.getVar("OVERRIDES", True) or "").split(":") or []

        #
        # Well let us see what breaks here. We used to iterate
        # over each variable and apply the override and then
        # do the line expanding.
        # If we have bad luck - which we will have - the keys
        # where in some order that is so important for this
        # method which we don't have anymore.
        # Anyway we will fix that and write test cases this
        # time.

        #
        # First we apply all overrides
        # Then  we will handle _append and _prepend
        #

        for o in overrides:
            # calculate '_'+override
            l = len(o) + 1

            # see if one should even try
            if o not in self._seen_overrides:
                continue

            vars = self._seen_overrides[o]
            for var in vars:
                name = var[:-l]
                try:
                    self[name] = self[var]
                except Exception:
                    bb.msg.note(1, bb.msg.domain.Data, "Untracked delVar")

        # now on to the appends and prepends
        if "_append" in self._special_values:
            appends = self._special_values["_append"] or []
            for append in appends:
                for (a, o) in self.getVarFlag(append, "_append") or []:
                    # maybe the OVERRIDE was not yet added so keep the append
                    if (o and o in overrides) or not o:
                        self.delVarFlag(append, "_append")
                    if o and not o in overrides:
                        continue

                    sval = self.getVar(append, False) or ""
                    sval += a
                    self.setVar(append, sval)


        if "_prepend" in self._special_values:
            prepends = self._special_values["_prepend"] or []

            for prepend in prepends:
                for (a, o) in self.getVarFlag(prepend, "_prepend") or []:
                    # maybe the OVERRIDE was not yet added so keep the prepend
                    if (o and o in overrides) or not o:
                        self.delVarFlag(prepend, "_prepend")
                    if o and not o in overrides:
                        continue

                    sval = a + (self.getVar(prepend, False) or "")
                    self.setVar(prepend, sval)

    def initVar(self, var):
        self.expand_cache = {}
        if not var in self.dict:
            self.dict[var] = {}

    def _findVar(self, var):
        dest = self.dict
        while dest:
            if var in dest:
                return dest[var]

            if "_data" not in dest:
                break
            dest = dest["_data"]

    def _makeShadowCopy(self, var):
        if var in self.dict:
            return

        local_var = self._findVar(var)

        if local_var:
            self.dict[var] = copy.copy(local_var)
        else:
            self.initVar(var)

    def setVar(self, var, value):
        self.expand_cache = {}
        match  = __setvar_regexp__.match(var)
        if match and match.group("keyword") in __setvar_keyword__:
            base = match.group('base')
            keyword = match.group("keyword")
            override = match.group('add')
            l = self.getVarFlag(base, keyword) or []
            l.append([value, override])
            self.setVarFlag(base, keyword, l)

            # todo make sure keyword is not __doc__ or __module__
            # pay the cookie monster
            try:
                self._special_values[keyword].add( base )
            except KeyError:
                self._special_values[keyword] = set()
                self._special_values[keyword].add( base )

            return

        if not var in self.dict:
            self._makeShadowCopy(var)

        # more cookies for the cookie monster
        if '_' in var:
            override = var[var.rfind('_')+1:]
            if override not in self._seen_overrides:
                self._seen_overrides[override] = set()
            self._seen_overrides[override].add( var )

        # setting var
        self.dict[var]["content"] = value

    def getVar(self, var, exp):
        value = self.getVarFlag(var, "content")

        if exp and value:
            return self.expand(value, var)
        return value

    def renameVar(self, key, newkey):
        """
        Rename the variable key to newkey
        """
        val = self.getVar(key, 0)
        if val is not None:
            self.setVar(newkey, val)

        for i in ('_append', '_prepend'):
            src = self.getVarFlag(key, i)
            if src is None:
                continue

            dest = self.getVarFlag(newkey, i) or []
            dest.extend(src)
            self.setVarFlag(newkey, i, dest)

            if i in self._special_values and key in self._special_values[i]:
                self._special_values[i].remove(key)
                self._special_values[i].add(newkey)

        self.delVar(key)

    def delVar(self, var):
        self.expand_cache = {}
        self.dict[var] = {}

    def setVarFlag(self, var, flag, flagvalue):
        if not var in self.dict:
            self._makeShadowCopy(var)
        self.dict[var][flag] = flagvalue

    def getVarFlag(self, var, flag):
        local_var = self._findVar(var)
        if local_var:
            if flag in local_var:
                return copy.copy(local_var[flag])
        return None

    def delVarFlag(self, var, flag):
        local_var = self._findVar(var)
        if not local_var:
            return
        if not var in self.dict:
            self._makeShadowCopy(var)

        if var in self.dict and flag in self.dict[var]:
            del self.dict[var][flag]

    def setVarFlags(self, var, flags):
        if not var in self.dict:
            self._makeShadowCopy(var)

        for i in flags:
            if i == "content":
                continue
            self.dict[var][i] = flags[i]

    def getVarFlags(self, var):
        local_var = self._findVar(var)
        flags = {}

        if local_var:
            for i in local_var:
                if i == "content":
                    continue
                flags[i] = local_var[i]

        if len(flags) == 0:
            return None
        return flags


    def delVarFlags(self, var):
        if not var in self.dict:
            self._makeShadowCopy(var)

        if var in self.dict:
            content = None

            # try to save the content
            if "content" in self.dict[var]:
                content  = self.dict[var]["content"]
                self.dict[var]            = {}
                self.dict[var]["content"] = content
            else:
                del self.dict[var]


    def createCopy(self):
        """
        Create a copy of self by setting _data to self
        """
        # we really want this to be a DataSmart...
        data = DataSmart(seen=self._seen_overrides.copy(), special=self._special_values.copy())
        data.dict["_data"] = self.dict

        return data

    def __iter__(self):
        seen = set()
        def _keys(d):
            if "_data" in d:
                for key in _keys(d["_data"]):
                    yield key

            for key in d:
                if key != "_data":
                    if not key in seen:
                        seen.add(key)
                        yield key
        return _keys(self.dict)

    def __len__(self):
        return len(frozenset(self))

    def __getitem__(self, item):
        return self.getVar(item, False)

    def __setitem__(self, var, value):
        self.setVar(var, value)

    def __delitem__(self, var):
        self.delVar(var)