source: code/trunk/src/tolua/lua/function.lua @ 1926

-- 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