source: code/trunk/src/tolua/lua/function.lua @ 4906

-- tolua: function class
-- Written by Waldemar Celes
-- TeCGraf/PUC-Rio
-- Jul 1998
-- $Id: function.lua 1597 2008-03-11 22:25:01Z ice-drezday $

-- This code is free software; you can redistribute it and/or modify it.
-- The software provided hereunder is on an "as is" basis, and
-- the author has no obligation to provide maintenance, support, updates,
-- enhancements, or modifications.


-- CEGUILua mod
-- exception handling
-- patch from Tov
-- modded by Lindquist
exceptionDefs = exceptionDefs or {}
exceptionDefs["std::exception"]             = {}
exceptionDefs["std::exception"]["var"]      = "&e"
exceptionDefs["std::exception"]["c_str"]    = "e.what()"

exceptionDefs["any"]                        = {}
exceptionDefs["any"]["var"]                 = ""
exceptionDefs["any"]["c_str"]               = '"Unknown"'

exceptionMessageBufferSize = 512

function outputExceptionError(f,e,errBuf)
    -- if the exception is not "..." then use the "c_str" info the get a real exception message
    local messageC_str = true
    if e.name == "any" then
        messageC_str = false
    end

    -- make a default e.ret if empty
    if not e.ret or e.ret == "" then
        e.ret = "nil,message"
    end

    -- create a default exceptionDef if we dont have one
    if not exceptionDefs[e.name] then
        exceptionDefs[e.name] = {}
        exceptionDefs[e.name].var = "&e"
        exceptionDefs[e.name].c_str = '"Unknown"'
    end

    -- print catch header
    local nameToEcho = e.name
    if nameToEcho == "any" then
        nameToEcho = "..."
    end
    if e.ret == "nil" then
        output("catch(",nameToEcho," CEGUIDeadException(",exceptionDefs[e.name].var,"))\n{\n")
    else
        output("catch(",nameToEcho,exceptionDefs[e.name].var,")\n{\n")
    end

    -- if just a nil
    if e.ret == "nil" then
        output("return 0;\n")
    -- if error should be raised
    elseif string.find(e.ret,"error") then
        if messageC_str then
            output("snprintf(errorBuffer,"..exceptionMessageBufferSize..",\"Exception of type '"..e.name.."' was thrown by function '"..f.."'\\nMessage: %s\","..exceptionDefs[e.name].c_str..");\n")
        else
            output("snprintf(errorBuffer,"..exceptionMessageBufferSize..",\"Unknown exception thrown by function '"..f.."'\");\n")
        end
        output("errorDoIt = true;\n")
    -- else go through the returns
    else
        -- buffer for message
        if string.find(e.ret,"message") and messageC_str and errBuf == false then
            output("char errorBuffer["..exceptionMessageBufferSize.."];\n")
        end
        local numrets = 0
        local retpat = "(%w+),?"
        local i,j,retval = string.find(e.ret,retpat)
        while i do
            local code = ""

            -- NIL
            if retval == "nil" then
                code = "tolua_pushnil(tolua_S);\n"

            -- MESSAGE
            elseif retval == "message" then
                if messageC_str then
                    code = "snprintf(errorBuffer,"..exceptionMessageBufferSize..",\"Exception of type '"..e.name.."' was thrown by function '"..f.."'\\nMessage: %s\","..exceptionDefs[e.name].c_str..");\ntolua_pushstring(tolua_S,errorBuffer);\n"
                else
                    code = "tolua_pushstring(tolua_S,\"Unknown exception thrown by function '"..f.."'\");\n"
                end

            -- TRUE
            elseif retval == "true" then
                code = "tolua_pushboolean(tolua_S, 1);\n"

            -- FALSE
            elseif retval == "false" then
                code = "tolua_pushboolean(tolua_S, 0);\n"
            end

            -- print code for this return value
            if code ~= "" then
                output(code)
                numrets = numrets + 1
            end

            -- next return value
            i,j,retval = string.find(e.ret,retpat,j+1)
        end
        output("return ",numrets,";\n")
    end

    -- print catch footer
    output("}\n")
end

function outputExceptionCatchBlocks(func,throws,err)
    for i=1,table.getn(throws) do
        outputExceptionError(func, throws[i], err)
    end

    -- if an error should be raised, we do it here
    if err then
        output("if (errorDoIt) {\n")
        output("luaL_error(tolua_S,errorBuffer);\n")
        output("}\n")
    end
end


-- Function class
-- Represents a function or a class method.
-- The following fields are stored:
--  mod  = type modifiers
--  type = type
--  ptr  = "*" or "&", if representing a pointer or a reference
--  name = name
--  lname = lua name
--  args  = list of argument declarations
--  const = if it is a method receiving a const "this".
classFunction = {
    mod = '',
    type = '',
    ptr = '',
    name = '',
    args = {n=0},
    const = '',
}
classFunction.__index = classFunction
setmetatable(classFunction,classFeature)

-- declare tags
function classFunction:decltype ()
    self.type = typevar(self.type)
    if strfind(self.mod,'const') then
        self.type = 'const '..self.type
        self.mod = gsub(self.mod,'const','')
    end
    local i=1
    while self.args[i] do
        self.args[i]:decltype()
        i = i+1
    end
end


-- Write binding function
-- Outputs C/C++ binding function.
function classFunction:supcode (local_constructor)

    local overload = strsub(self.cname,-2,-1) - 1  -- indicate overloaded func
    local nret = 0      -- number of returned values
    local class = self:inclass()
    local _,_,static = strfind(self.mod,'^%s*(static)')
    if class then

        if self.name == 'new' and self.parent.flags.pure_virtual then
            -- no constructor for classes with pure virtual methods
            return
        end

        if local_constructor then
           output("/* method: new_local of class ",class," */")
       else
           output("/* method:",self.name," of class ",class," */")
       end
    else
        output("/* function:",self.name," */")
    end

    if local_constructor then
        output("#ifndef TOLUA_DISABLE_"..self.cname.."_local")
        output("\nstatic int",self.cname.."_local","(lua_State* tolua_S)")
    else
        output("#ifndef TOLUA_DISABLE_"..self.cname)
        output("\nstatic int",self.cname,"(lua_State* tolua_S)")
    end
    output("{")

    -- check types
    if overload < 0 then
        output('#ifndef TOLUA_RELEASE\n')
    end
    output(' tolua_Error tolua_err;')
    output(' if (\n')
    -- check self
    local narg
    if class then narg=2 else narg=1 end
    if class then
        local func = 'tolua_isusertype'
        local type = self.parent.type
        if self.name=='new' or static~=nil then
            func = 'tolua_isusertable'
            type = self.parent.type
        end
        if self.const ~= '' then
            type = "const "..type
        end
        output('     !'..func..'(tolua_S,1,"'..type..'",0,&tolua_err) ||\n')
    end
    -- check args
    if self.args[1].type ~= 'void' then
        local i=1
        while self.args[i] do
            local btype = isbasic(self.args[i].type)
            if btype ~= 'value' and btype ~= 'state' then
                output('     !'..self.args[i]:outchecktype(narg)..' ||\n')
            end
            if btype ~= 'state' then
                narg = narg+1
            end
            i = i+1
        end
    end
    -- check end of list
    output('     !tolua_isnoobj(tolua_S,'..narg..',&tolua_err)\n )')
    output('  goto tolua_lerror;')

    output(' else\n')
    if overload < 0 then
        output('#endif\n')
    end
    output(' {')

    -- declare self, if the case
    local narg
    if class then narg=2 else narg=1 end
    if class and self.name~='new' and static==nil then
        output(' ',self.const,self.parent.type,'*','self = ')
        output('(',self.const,self.parent.type,'*) ')
        output('tolua_tousertype(tolua_S,1,0);')
    elseif static then
        _,_,self.mod = strfind(self.mod,'^%s*static%s%s*(.*)')
    end
    -- declare parameters
    if self.args[1].type ~= 'void' then
        local i=1
        while self.args[i] do
            self.args[i]:declare(narg)
            if isbasic(self.args[i].type) ~= "state" then
                narg = narg+1
            end
            i = i+1
        end
    end

    -- check self
    if class and self.name~='new' and static==nil then
        output('#ifndef TOLUA_RELEASE\n')
        output('  if (!self) tolua_error(tolua_S,"invalid \'self\' in function \''..self.name..'\'",NULL);');
        output('#endif\n')
    end

    -- get array element values
    if class then narg=2 else narg=1 end
    if self.args[1].type ~= 'void' then
        local i=1
        while self.args[i] do
            self.args[i]:getarray(narg)
            narg = narg+1
            i = i+1
        end
    end

    --------------------------------------------------
    -- CEGUILua mod
    -- init exception handling
    local throws = false
    do
        local pattern = "tolua_throws|.*|"
        local i,j = string.find(self.mod, pattern)
        if i then
            throws = {}
            -- ensure table is empty.  Used to be: table.setn(throws,0)
            for x in pairs(throws) do
                throws[x] = nil
            end
            local excepts = string.sub(self.mod, i+12,j)
            local epattern = "|.-|"
            local i,j = string.find(excepts, epattern)
            while i do
                local e = string.sub(excepts,i+1,j-1)
                local _,_,name,rest = string.find(e, "([%w:_]+),?(.*)")
                table.insert(throws,{name=name, ret=rest})
                i,j = string.find(excepts, epattern, j)
            end
            self.mod = string.gsub(self.mod, pattern, "")
        end
    end
    local exRaiseError = false
    --------------------------------------------------

    local out = string.find(self.mod, "tolua_outside")

    ---------------
    -- CEGUILua mod
    -- remove "tolua_outside" from self.mod
    if out then
        self.mod = string.gsub(self.mod, "tolua_outside", "")
    end

    -- call function
    if class and self.name=='delete' then
        output('  delete self;')
    elseif class and self.name == 'operator&[]' then
        if flags['1'] then -- for compatibility with tolua5 ?
            output('  self->operator[](',self.args[1].name,'-1) = ',self.args[2].name,';')
        else
            output('  self->operator[](',self.args[1].name,') = ',self.args[2].name,';')
        end
    else
    -- CEGUILua mod begin- throws
    if throws then
        for i=1,table.getn(throws) do
            if string.find(throws[i].ret, "error") then
                output("char errorBuffer["..exceptionMessageBufferSize.."];\n")
                output("bool errorDoIt = false;\n")
                exRaiseError = true
                break
            end
        end
        output("try\n")
    end
    -- CEGUILua mod end - throws
    output('  {')
    if self.type ~= '' and self.type ~= 'void' then
        output('  ',self.mod,self.type,self.ptr,'tolua_ret = ')
        output('(',self.mod,self.type,self.ptr,') ')
    else
        output('  ')
    end
    if class and self.name=='new' then
        output('new',self.type,'(')
    elseif class and static then
        if out then
            output(self.name,'(')
        else
            output(class..'::'..self.name,'(')
        end
    elseif class then
        if out then
            output(self.name,'(')
        else
            if self.cast_operator then
                output('static_cast<',self.mod,self.type,self.ptr,'>(*self')
            else
                output('self->'..self.name,'(')
            end
        end
    else
        output(self.name,'(')
    end

    if out and not static then
        output('self')
        if self.args[1] and self.args[1].name ~= '' then
            output(',')
        end
    end
    -- write parameters
    local i=1
    while self.args[i] do
        self.args[i]:passpar()
        i = i+1
        if self.args[i] then
            output(',')
        end
    end

    if class and self.name == 'operator[]' and flags['1'] then
        output('-1);')
    else
        output(');')
    end

    -- return values
    if self.type ~= '' and self.type ~= 'void' then
        nret = nret + 1
        local t,ct = isbasic(self.type)
        if t then
            if self.cast_operator and _basic_raw_push[t] then
                output('   ',_basic_raw_push[t],'(tolua_S,(',ct,')tolua_ret);')
            else
                output('   tolua_push'..t..'(tolua_S,(',ct,')tolua_ret);')
            end
            else
                t = self.type
                new_t = string.gsub(t, "const%s+", "")
                if self.ptr == '' then
                    output('   {')
                    output('#ifdef __cplusplus\n')
                    output('    void* tolua_obj = new',new_t,'(tolua_ret);')
                    output('    tolua_pushusertype_and_takeownership(tolua_S,tolua_obj,"',t,'");')
                    output('#else\n')
                    output('    void* tolua_obj = tolua_copy(tolua_S,(void*)&tolua_ret,sizeof(',t,'));')
                    output('    tolua_pushusertype_and_takeownership(tolua_S,tolua_obj,"',t,'");')
                    output('#endif\n')
                    output('   }')
                elseif self.ptr == '&' then
                    output('   tolua_pushusertype(tolua_S,(void*)&tolua_ret,"',t,'");')
                else
                    if local_constructor then
                        output('   tolua_pushusertype_and_takeownership(tolua_S,(void *)tolua_ret,"',t,'");')
                    else
                        output('   tolua_pushusertype(tolua_S,(void*)tolua_ret,"',t,'");')
                    end
                end
            end
        end
        local i=1
        while self.args[i] do
            nret = nret + self.args[i]:retvalue()
            i = i+1
        end
        output('  }')

        ------------------------------------------
        -- CEGUILua mod
        -- finish exception handling
        -- catch
        if throws then
            outputExceptionCatchBlocks(self.name, throws, exRaiseError)
        end
        ------------------------------------------

        -- set array element values
        if class then narg=2 else narg=1 end
        if self.args[1].type ~= 'void' then
            local i=1
            while self.args[i] do
                self.args[i]:setarray(narg)
                narg = narg+1
                i = i+1
            end
        end

        -- free dynamically allocated array
        if self.args[1].type ~= 'void' then
            local i=1
            while self.args[i] do
                self.args[i]:freearray()
                i = i+1
            end
        end
    end

    output(' }')
    output(' return '..nret..';')

    -- call overloaded function or generate error
    if overload < 0 then

        output('#ifndef TOLUA_RELEASE\n')
        output('tolua_lerror:\n')
        output(' tolua_error(tolua_S,"#ferror in function \''..self.lname..'\'.",&tolua_err);')
        output(' return 0;')
        output('#endif\n')
    else
        local _local = ""
        if local_constructor then
            _local = "_local"
        end
        output('tolua_lerror:\n')
        output(' return '..strsub(self.cname,1,-3)..format("%02d",overload).._local..'(tolua_S);')
    end
    output('}')
    output('#endif //#ifndef TOLUA_DISABLE\n')
    output('\n')

    -- recursive call to write local constructor
    if class and self.name=='new' and not local_constructor then

        self:supcode(1)
    end

end


-- register function
function classFunction:register (pre)

    if not self:check_public_access() then
        return
    end

    if self.name == 'new' and self.parent.flags.pure_virtual then
        -- no constructor for classes with pure virtual methods
        return
    end

    output(pre..'tolua_function(tolua_S,"'..self.lname..'",'..self.cname..');')
    if self.name == 'new' then
        output(pre..'tolua_function(tolua_S,"new_local",'..self.cname..'_local);')
        output(pre..'tolua_function(tolua_S,".call",'..self.cname..'_local);')
        --output(' tolua_set_call_event(tolua_S,'..self.cname..'_local, "'..self.parent.type..'");')
    end
end

-- Print method
function classFunction:print (ident,close)
    print(ident.."Function{")
    print(ident.." mod  = '"..self.mod.."',")
    print(ident.." type = '"..self.type.."',")
    print(ident.." ptr  = '"..self.ptr.."',")
    print(ident.." name = '"..self.name.."',")
    print(ident.." lname = '"..self.lname.."',")
    print(ident.." const = '"..self.const.."',")
    print(ident.." cname = '"..self.cname.."',")
    print(ident.." lname = '"..self.lname.."',")
    print(ident.." args = {")
    local i=1
    while self.args[i] do
        self.args[i]:print(ident.."  ",",")
        i = i+1
    end
    print(ident.." }")
    print(ident.."}"..close)
end

-- check if it returns an object by value
function classFunction:requirecollection (t)
    local r = false
    if self.type ~= '' and not isbasic(self.type) and self.ptr=='' then
        local type = gsub(self.type,"%s*const%s+","")
        t[type] = "tolua_collect_" .. clean_template(type)
        r = true
    end
    local i=1
    while self.args[i] do
        r = self.args[i]:requirecollection(t) or r
        i = i+1
    end
    return r
end

-- determine lua function name overload
function classFunction:overload ()
    return self.parent:overload(self.lname)
end


function param_object(par) -- returns true if the parameter has an object as its default value

    if not string.find(par, '=') then return false end -- it has no default value

    local _,_,def = string.find(par, "=(.*)$")

    if string.find(par, "|") then -- a list of flags

        return true
    end

    if string.find(par, "%*") then -- it's a pointer with a default value

        if string.find(par, '=%s*new') then -- it's a pointer with an instance as default parameter.. is that valid?
            return true
        end
        return false -- default value is 'NULL' or something
    end


    if string.find(par, "[%(&]") then
        return true
    end -- default value is a constructor call (most likely for a const reference)

    --if string.find(par, "&") then

    --    if string.find(def, ":") or string.find(def, "^%s*new%s+") then

    --        -- it's a reference with default to something like Class::member, or 'new Class'
    --        return true
    --    end
    --end

    return false -- ?
end

function strip_last_arg(all_args, last_arg) -- strips the default value from the last argument

    local _,_,s_arg = string.find(last_arg, "^([^=]+)")
    last_arg = string.gsub(last_arg, "([%%%(%)])", "%%%1");
    all_args = string.gsub(all_args, "%s*,%s*"..last_arg.."%s*%)%s*$", ")")
    return all_args, s_arg
end



-- Internal constructor
function _Function (t)
    setmetatable(t,classFunction)

    if t.const ~= 'const' and t.const ~= '' then
        error("#invalid 'const' specification")
    end

    append(t)
    if t:inclass() then
        --print ('t.name is '..t.name..', parent.name is '..t.parent.name)
        if string.gsub(t.name, "%b<>", "") == string.gsub(t.parent.original_name or t.parent.name, "%b<>", "") then
            t.name = 'new'
            t.lname = 'new'
            t.parent._new = true
            t.type = t.parent.name
            t.ptr = '*'
        elseif string.gsub(t.name, "%b<>", "") == '~'..string.gsub(t.parent.original_name or t.parent.name, "%b<>", "") then
            t.name = 'delete'
            t.lname = 'delete'
            t.parent._delete = true
        end
    end
    t.cname = t:cfuncname("tolua")..t:overload(t)
    return t
end

-- Constructor
-- Expects three strings: one representing the function declaration,
-- another representing the argument list, and the third representing
-- the "const" or empty string.
function Function (d,a,c)
    --local t = split(strsub(a,2,-2),',') -- eliminate braces
    --local t = split_params(strsub(a,2,-2))

    if not flags['W'] and string.find(a, "%.%.%.%s*%)") then

        warning("Functions with variable arguments (`...') are not supported. Ignoring "..d..a..c)
        return nil
    end


    local i=1
    local l = {n=0}

    a = string.gsub(a, "%s*([%(%)])%s*", "%1")
    local t,strip,last = strip_pars(strsub(a,2,-2));
    if strip then
        --local ns = string.sub(strsub(a,1,-2), 1, -(string.len(last)+1))
        local ns = join(t, ",", 1, last-1)

        ns = "("..string.gsub(ns, "%s*,%s*$", "")..')'
        --ns = strip_defaults(ns)

        Function(d, ns, c)
        for i=1,last do
            t[i] = string.gsub(t[i], "=.*$", "")
        end
    end

    while t[i] do
        l.n = l.n+1
        l[l.n] = Declaration(t[i],'var',true)
        i = i+1
    end
    local f = Declaration(d,'func')
    f.args = l
    f.const = c
    return _Function(f)
end

function join(t, sep, first, last)

    first = first or 1
    last = last or table.getn(t)
    local lsep = ""
    local ret = ""
    local loop = false
    for i = first,last do

        ret = ret..lsep..t[i]
        lsep = sep
        loop = true
    end
    if not loop then
        return ""
    end

    return ret
end

function strip_pars(s)

    local t = split_c_tokens(s, ',')
    local strip = false
    local last

    for i=t.n,1,-1 do

        if not strip and param_object(t[i]) then
            last = i
            strip = true
        end
        --if strip then
        --    t[i] = string.gsub(t[i], "=.*$", "")
        --end
    end

    return t,strip,last

end

function strip_defaults(s)

    s = string.gsub(s, "^%(", "")
    s = string.gsub(s, "%)$", "")

    local t = split_c_tokens(s, ",")
    local sep, ret = "",""
    for i=1,t.n do
        t[i] = string.gsub(t[i], "=.*$", "")
        ret = ret..sep..t[i]
        sep = ","
    end

    return "("..ret..")"
end