src: Update init

[nit.git] / src / nitni / nitni_callbacks.nit

# This file is part of NIT ( http://www.nitlanguage.org ).
#
# Copyright 2012-2013 Alexis Laferrière <alexis.laf@xymus.net>
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# nitni services related to callbacks (used underneath the FFI)
module nitni_callbacks

import modelbuilder
intrude import rapid_type_analysis

import nitni_base

redef class ToolContext
        var verify_nitni_callback_phase: Phase = new VerifyNitniCallbacksPhase(self, [typing_phase])
end

# * checks for the validity of callbacks
# * store the callbacks on each method
class VerifyNitniCallbacksPhase
        super Phase

        redef fun process_npropdef(npropdef)
        do
                if not npropdef isa AMethPropdef then return
                var mpropdef = npropdef.mpropdef
                if mpropdef == null then return
                if not mpropdef.is_extern then return

                npropdef.verify_nitni_callbacks(toolcontext)
        end
end

# Provides a better API but mainly the same content as AExternCalls
class ForeignCallbackSet
        # set of imported functions, cached to avoid repetitions
        var callbacks: Set[ MExplicitCall ] = new HashSet[ MExplicitCall ]

        # set of imported functions, cached to avoid repetitions
        var supers: Set[ MExplicitSuper ] = new HashSet[ MExplicitSuper ]

        # set of relevant types, cached to avoid repetitions
        var types: Set[ MType ] = new HashSet[ MType ]

        # set of imported casts and as, cached to avoid repetitions
        var casts: Set[ MExplicitCast ] = new HashSet[ MExplicitCast ]

        # Utility function, must be called only when all other maps are filled
        private var all_cached: nullable Set[NitniCallback] = null
        fun all: Set[NitniCallback]
        do
                var cached = all_cached
                if cached != null then return cached

                var set = new HashSet[NitniCallback]
                set.add_all(callbacks)
                set.add_all(supers)
                set.add_all(types)
                set.add_all(casts)
                
                self.all_cached = set
                return set
        end

        # Integrate content from the `other` set into this one
        fun join(other: ForeignCallbackSet)
        do
                callbacks.add_all( other.callbacks )
                supers.add_all( other.supers )
                types.add_all( other.types )
                casts.add_all( other.casts )
        end
end

redef class AMethPropdef
        private var foreign_callbacks_cache: nullable ForeignCallbackSet = null

        # All foreign callbacks from this method
        fun foreign_callbacks: ForeignCallbackSet
        do
                var fcs = foreign_callbacks_cache
                assert fcs != null else print "Error: attempting to access nitni callbacks before phase 'verify_nitni_callback_phase'."
                return fcs
        end

        # Verifiy the validity of the explicit callbacks to Nit
        # also fills the set returned by foreign_callbacks
        fun verify_nitni_callbacks(toolcontext: ToolContext)
        do
                if foreign_callbacks_cache != null then return

                var fcs = new ForeignCallbackSet

                var mmodule = mpropdef.mclassdef.mmodule

                # receiver
                var recv_type = mpropdef.mclassdef.bound_mtype
                fcs.types.add(recv_type)

                # return type
                var rmt = mpropdef.msignature.return_mtype
                if rmt != null then
                        if rmt isa MFormalType then
                                var mclass_type = mpropdef.mclassdef.bound_mtype
                                rmt = rmt.anchor_to(mmodule, mclass_type)
                        end
                        var mtype = rmt.resolve_for(recv_type, recv_type, mmodule, true)
                        fcs.types.add(mtype)
                end

                # params
                for p in mpropdef.msignature.mparameters do
                        var mtype = p.mtype.resolve_for(recv_type, recv_type, mmodule, true)
                        if mtype isa MFormalType then
                                var mclass_type = mpropdef.mclassdef.bound_mtype
                                mtype = mtype.anchor_to(mmodule, mclass_type)
                        end
                        fcs.types.add( mtype )
                end

                # explicit callbacks
                if n_extern_calls != null then
                        for ec in n_extern_calls.n_extern_calls do
                                ec.verify_and_collect(self, fcs, toolcontext)
                        end
                end

                # store result
                foreign_callbacks_cache = fcs
        end

        redef fun accept_rapid_type_visitor(v)
        do
                if foreign_callbacks_cache == null then return

                for cb in foreign_callbacks.callbacks do v.add_send(cb.recv_mtype, cb.mproperty.as(MMethod))
                for cast in foreign_callbacks.casts do v.add_cast_type(cast.to)
                for sup in foreign_callbacks.supers do
                        v.analysis.add_super_send(sup.from.mclassdef.mclass.mclass_type, sup.from.as(MMethodDef))
                end
                for t in foreign_callbacks.types do if t isa MClassType then v.add_type t
        end
end

# Classification for all nitni callbacks
interface NitniCallback
end

redef class MType
        super NitniCallback
end

# A prossible call from C, declared explictly after the `import` keyword
class MExplicitCall
        super NitniCallback

        # Previously resolved mtype
        var recv_mtype: MClassType
        var mproperty: MProperty
        var from_mmodule: MModule

        fun fill_type_for( callback_set: ForeignCallbackSet, from: MModule )
        do
                var first = mproperty.lookup_first_definition( from, recv_mtype )
                var mclassdef = first.mclassdef
                var bound_mtype = mclassdef.bound_mtype

                # receiver / constructor return
                recv_mtype = recv_mtype.resolve_for(bound_mtype, bound_mtype, from, true)
                recv_mtype = recv_mtype.anchor_to(from, bound_mtype)
                callback_set.types.add( recv_mtype )

                if first isa MMethodDef then
                        var rmt = first.msignature.return_mtype
                        if rmt != null then
                                rmt = rmt.resolve_for(bound_mtype, bound_mtype, from, true)
                                rmt = rmt.anchor_to(from, bound_mtype)
                                callback_set.types.add( rmt )
                        end

                        for p in first.msignature.mparameters do
                                var param_mtype = p.mtype.resolve_for(recv_mtype, recv_mtype, from, true)
                                param_mtype = param_mtype.resolve_for(bound_mtype, bound_mtype, from, true)
                                param_mtype = param_mtype.anchor_to(from, bound_mtype)
                                callback_set.types.add( param_mtype )
                        end
                end
        end

        # Signature of this call in C as seen by user
        fun csignature: String
        do
                var mproperty = self.mproperty
                if mproperty isa MMethod then
                        var signature = mproperty.intro.msignature
                        assert signature != null

                        var creturn_type
                        if mproperty.is_init then
                                creturn_type = recv_mtype.cname
                        else if signature.return_mtype != null then
                                var ret_mtype = signature.return_mtype
                                ret_mtype = ret_mtype.resolve_for(recv_mtype, recv_mtype, from_mmodule, true)
                                creturn_type = ret_mtype.cname
                        else
                                creturn_type = "void"
                        end

                        var cname
                        if mproperty.is_init then
                                if mproperty.name == "init" or mproperty.name == "new" or mproperty.name == "defaultinit" then
                                        cname = "new_{recv_mtype.mangled_cname}"
                                else
                                        cname = "new_{recv_mtype.mangled_cname}_{mproperty.short_cname}"
                                end
                        else
                                cname = "{recv_mtype.mangled_cname}_{mproperty.short_cname}"
                        end

                        var cparams = new List[String]
                        if not mproperty.is_init then
                                cparams.add( "{recv_mtype.cname} self" )
                        end
                        for p in signature.mparameters do
                                var param_mtype = p.mtype.resolve_for(recv_mtype, recv_mtype, from_mmodule, true)
                                cparams.add( "{param_mtype.cname} {p.name}" )
                        end

                        return "{creturn_type} {cname}( {cparams.join(", ")} )"
                else
                        print "Type of callback from foreign code not yet supported."
                        abort
                end
        end

        redef fun hash do return recv_mtype.hash + 1024 * mproperty.hash
        redef fun ==(o) do return o isa MExplicitCall and recv_mtype == o.recv_mtype and mproperty == o.mproperty
end

class MExplicitSuper
        super NitniCallback

        var from: MPropDef

        redef fun hash do return from.hash
        redef fun ==(o) do return o isa MExplicitSuper and from == o.from
end

class MExplicitCast
        super NitniCallback

        var from: MType
        var to: MType

        fun check_cname: String do return "{from.mangled_cname}_is_a_{to.mangled_cname}"

        fun cast_cname: String do return "{from.mangled_cname}_as_{to.mangled_cname}"

        redef fun hash do return from.hash + 1024 * to.hash
        redef fun ==(o) do return o isa MExplicitCast and from == o.from and to == o.to
end

redef class AExternCall
        # Verify this explicit declaration of call from C and collect all relevant callbacks
        fun verify_and_collect(npropdef: AMethPropdef, callback_set: ForeignCallbackSet,
                toolcontext: ToolContext) is abstract
end

redef class ALocalPropExternCall
        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mmodule = npropdef.mpropdef.mclassdef.mmodule
                var mclass_type = npropdef.mpropdef.mclassdef.bound_mtype
                var m_name = n_methid.collect_text
                var method = toolcontext.modelbuilder.try_get_mproperty_by_name2( self,
                        mmodule, mclass_type, m_name )

                if method == null then
                        toolcontext.error(location, "Error: local method `{m_name}` not found.")
                        return
                end

                var explicit_call = new MExplicitCall(mclass_type, method, mmodule)
                callback_set.callbacks.add(explicit_call)

                explicit_call.fill_type_for(callback_set, mmodule)
        end
end

redef class AFullPropExternCall
        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mmodule = npropdef.mpropdef.mclassdef.mmodule
                var mclassdef = npropdef.mpropdef.mclassdef
                var mclass_type = mclassdef.bound_mtype
                var mtype = toolcontext.modelbuilder.resolve_mtype(mclassdef, n_type)

                if mtype == null then return

                if mtype isa MFormalType then
                        mtype = mtype.anchor_to(mmodule, mclass_type)
                end

                if mtype isa MNullableType then
                        toolcontext.error(location, "Error: type `{n_type.collect_text}` is nullable and thus cannot be the receiver." )
                        return
                end

                var m_name = n_methid.collect_text
                var method = toolcontext.modelbuilder.try_get_mproperty_by_name2( self,
                        mmodule, mtype, m_name )

                if method == null then
                        toolcontext.error(location, "Error: method `{m_name}` not found in `{n_type.collect_text}`." )
                        return
                end

                var explicit_call = new MExplicitCall(mtype.as(MClassType), method, mmodule)
                callback_set.callbacks.add(explicit_call)
                explicit_call.fill_type_for(callback_set, mmodule)
        end
end

redef class AInitPropExternCall
        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mmodule = npropdef.mpropdef.mclassdef.mmodule
                var mclassdef = npropdef.mpropdef.mclassdef
                var mtype = toolcontext.modelbuilder.resolve_mtype(mclassdef, n_type)
                if mtype == null then return

                if not mtype isa MClassType then
                        toolcontext.error(location, "Error: type `{n_type.collect_text}` is not a class and thus cannot be used to instantiate a new instance." )
                        return
                end

                var meth_name = "new"
                var meth = toolcontext.modelbuilder.try_get_mproperty_by_name2( self,
                        mmodule, mtype, meth_name )

                if meth == null then
                        meth_name = "defaultinit"
                        meth = toolcontext.modelbuilder.try_get_mproperty_by_name2( self,
                                mmodule, mtype, meth_name )
                end

                if meth == null then
                        toolcontext.error(location, "Error: method `{meth_name}` not found in `{n_type.collect_text}`." )
                        return
                end

                var explicit_call = new MExplicitCall(mtype, meth, mmodule)
                callback_set.callbacks.add(explicit_call)
                explicit_call.fill_type_for(callback_set, mmodule)
        end
end

redef class ASuperExternCall
        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                callback_set.supers.add( new MExplicitSuper( npropdef.mpropdef.as(not null) ) )
                callback_set.types.add( npropdef.mpropdef.mclassdef.mclass.mclass_type )
                npropdef.mpropdef.has_supercall = true
        end
end

redef class ACastExternCall
        fun from_mtype: MType is abstract
        fun to_mtype: MType is abstract

        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var from = from_mtype
                var to = to_mtype

                callback_set.types.add(from)
                callback_set.types.add(to)

                callback_set.casts.add(new MExplicitCast(from, to))
        end
end

redef class ACastAsExternCall
        redef fun from_mtype do return n_from_type.mtype.as(not null)
        redef fun to_mtype do return n_to_type.mtype.as(not null)

        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mclassdef = npropdef.mpropdef.mclassdef
                toolcontext.modelbuilder.resolve_mtype_unchecked(mclassdef, n_from_type, true)
                toolcontext.modelbuilder.resolve_mtype_unchecked(mclassdef, n_to_type, true)
                super
        end
end

redef class AAsNullableExternCall
        redef fun from_mtype do return n_type.mtype.as(not null)
        redef fun to_mtype do return n_type.mtype.as_nullable

        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mclassdef = npropdef.mpropdef.mclassdef
                toolcontext.modelbuilder.resolve_mtype_unchecked(mclassdef, n_type, true)
                super
        end
end

redef class AAsNotNullableExternCall
        redef fun from_mtype do return n_type.mtype.as_nullable
        redef fun to_mtype do
                var mtype = n_type.mtype.as(not null)
                mtype = mtype.undecorate
                return mtype
        end

        redef fun verify_and_collect(npropdef, callback_set, toolcontext)
        do
                var mclassdef = npropdef.mpropdef.mclassdef
                toolcontext.modelbuilder.resolve_mtype_unchecked(mclassdef, n_type, true)
                super
        end
end