hcl/lib2/h3-compilers.adb
2021-11-07 17:32:50 +00:00

295 lines
7.2 KiB
Ada

with H3.Utf8;
with ada.text_io;
package body H3.Compilers is
type Char_Array is array(System_Index range<>) of Standard.Character;
package Utf8 is new H3.Utf8(Standard.Character, S.Rune, Char_Array, S.Rune_Array);
LB_EOF: constant S.Rune_Array := (R.V.Left_Arrow,R.V.UC_E,R.V.UC_O,R.V.UC_F,R.V.Right_Arrow); -- <EOF>
LB_XINCLUDE: constant S.Rune_Array := (R.V.Number_Sign,R.V.LC_I,R.V.LC_N,R.V.LC_C,R.V.LC_L,R.V.LC_U,R.V.LC_D,R.V.LC_E); -- #include
procedure Set_Lexer_State (C: in out Compiler; State: in Lexer_State) is
begin
C.Lx.State := State;
end Set_Lexer_State;
procedure Set_Lexer_State (C: in out Compiler; State: in Lexer_State; Ch: in R.Rune) is
begin
-- change the lexer state while storing the first character in the token buffer.
C.Lx.State := State;
S.Clear (C.Tk.Buf);
S.Append (C.Tk.Buf, Ch);
end Set_Lexer_State;
procedure Set_Lexer_State (C: in out Compiler; State: in Lexer_State; Code: in R.Code) is
begin
Set_Lexer_State (C, State, R.To_Rune(Code));
end Set_Lexer_State;
procedure Set_Parser_State (C: in out Compiler; State: in Parser_State) is
begin
C.Ps.State := State;
end Set_Parser_State;
procedure Parse_Start (C: in out Compiler) is
begin
case C.Tk.Id is
when TK_BSTR =>
null;
when TK_BYTE =>
null;
when TK_CHAR =>
null;
when TK_CSTR =>
null;
when TK_DIRECTIVE =>
if C.Tk.Buf.Equals(LB_XINCLUDE) then
Set_Parser_State (C, PS_INCLUDE);
else
raise Syntax_Error;
end if;
when TK_EOF =>
null;
when TK_EOL =>
null;
when TK_GE =>
null;
when TK_GT =>
null;
when TK_IDENT =>
null;
when TK_LE =>
null;
when TK_LT =>
null;
when TK_SEMICOLON =>
null;
end case;
end Parse_Start;
procedure Start_Inclusion (C: in out Compiler; Name: in S.Rune_Array) is
Top: System_Index;
begin
if C.St.Top = C.St.Items'Last then
raise Syntax_Error; -- TODO: inclusion depth too deep
end if;
Top := C.St.Top + 1;
Ada.Text_IO.Open (C.St.Items(Top).Handle, Ada.Text_IO.In_File, Standard.String(Utf8.From_Unicode_String(Name)));
C.St.Top := Top;
end Start_Inclusion;
procedure End_Inclusion (C: in out Compiler) is
begin
Ada.Text_IO.Close (C.St.Items(C.St.Top).Handle);
C.St.Top := C.St.Top - 1;
end End_Inclusion;
procedure Parse_Include (C: in out Compiler) is
begin
if C.Tk.Id = TK_CSTR then
-- arrange to feed more data from the included file.
Start_Inclusion (C, S.To_Rune_Array(C.Tk.Buf));
null;
else
raise Syntax_Error; -- string literal required
end if;
end Parse_Include;
procedure Parse_Include_End (C: in out Compiler) is
begin
if C.Tk.Id /= TK_SEMICOLON then
raise Syntax_Error;
end if;
-- TODO: put the state back to START???
end Parse_Include_End;
procedure Got_Token (C: in out Compiler) is
begin
--case C.P.State IS
-- when START =>
-- null;
--end case;
ada.text_io.put (C.Tk.Id'Img);
ada.text_io.put (" ");
for i in C.Tk.Buf.Get_First_Index .. C.Tk.Buf.Get_Last_Index loop
ada.text_io.put (standard.character'val(S.Rune'Pos(C.Tk.Buf.Get_Item(i))));
end loop;
ada.text_io.put_line("");
case C.Ps.State is
when PS_START =>
Parse_Start (C);
when PS_INCLUDE =>
Parse_Include (C);
when others =>
raise Syntax_Error; -- TODO: change this...
end case;
end Got_Token;
procedure Start_Token (C: in out Compiler) is
begin
C.Tk.Id := TK_EOF; -- indicate the token id is not set yet
-- TODO: store token location.
S.Clear (C.Tk.Buf);
end Start_Token;
procedure Start_Token (C: in out Compiler; Ch: in R.Rune) is
begin
Start_Token (C);
S.Append (C.Tk.Buf, Ch);
end Start_Token;
procedure Start_Token (C: in out Compiler; Code: in R.Code) is
begin
Start_Token (C, R.To_Rune(Code));
end Start_Token;
procedure Start_Token (C: in out Compiler; Str: in S.Rune_Array) is
begin
Start_Token (C);
S.Append (C.Tk.Buf, Str);
end Start_Token;
procedure Feed_Token (C: in out Compiler; Ch: in R.Rune) is
begin
S.Append (C.Tk.Buf, Ch);
end Feed_Token;
procedure Feed_Token (C: in out Compiler; Code: in R.Code) is
begin
Feed_Token(C, R.To_Rune(Code));
end Feed_Token;
procedure End_Token (C: in out Compiler; Id: in Token_Id) is
begin
C.Tk.Id := Id;
Got_Token (C);
Set_Lexer_State (C, LX_START);
end End_Token;
procedure End_Token (C: in out Compiler; Id: in Token_Id; Ch: in R.Rune) is
begin
S.Append (C.Tk.Buf, Ch);
C.Tk.Id := Id;
Got_Token (C);
Set_Lexer_State (C, LX_START);
end End_Token;
procedure End_Token (C: in out Compiler; Id: in Token_Id; Code: in R.Code) is
begin
S.Append (C.Tk.Buf, R.To_Rune(Code));
C.Tk.Id := Id;
Got_Token (C);
Set_Lexer_State (C, LX_START);
end End_Token;
procedure Feed_Char_Code (C: in out Compiler; Code: in R.Code) is
begin
<<Start_Over>>
if R.Is_Eof(Code) then
ada.text_io.put_line ("EOF");
else
ada.text_io.put_line (R.To_Rune(Code)'Img);
end if;
case C.Lx.State is
when LX_START =>
if R.Is_Eof(Code) then
Start_Token (C, LB_EOF);
End_Token (C, TK_EOF);
-- this procedure doesn't prevent you from feeding more
-- after EOF. but it's not desirable to feed more after EOF.
elsif R.Is_Space(Code) then
-- ignore. carry on
null;
elsif R.Is_Alpha(Code) then
Set_Lexer_State (C, LX_IDENT, Code);
elsif R.Is_Digit(Code) then
Set_Lexer_State (C, LX_NUMBER, Code);
elsif R.Is_Rune(Code, R.V.Semicolon) then
Start_Token (C, Code);
End_Token (C, TK_SEMICOLON);
elsif R.Is_Rune(Code, R.V.Left_Arrow) then
Set_Lexer_State (C, LX_OP_LESS, Code);
elsif R.Is_Rune(Code, R.V.Right_Arrow) then
Set_Lexer_State (C, LX_OP_GREATER, Code);
elsif R.Is_Rune(Code, R.V.Number_Sign) then
Set_Lexer_State (C, LX_DIRECTIVE);
else
raise Syntax_Error;
end if;
when LX_DIRECTIVE =>
if R.Is_Alnum(Code) or else R.Is_Rune(Code, R.V.Underline) then
Feed_Token (C, Code);
else
End_Token (C, TK_DIRECTIVE);
goto Start_Over;
end if;
when LX_OP_GREATER =>
if R.Is_Rune(Code, R.V.Equal_Sign) then
End_Token (C, TK_GE, Code);
else
End_Token (C, TK_GT);
goto Start_Over;
end if;
when LX_OP_LESS =>
if R.Is_Rune(Code, R.V.Equal_sign) then
End_Token (C, TK_LE, Code);
else
End_Token (C, TK_LT);
goto Start_Over;
end if;
when LX_COMMENT =>
null;
when LX_IDENT =>
if R.Is_Alnum(Code) or else R.Is_Rune(Code, R.V.Underline) then
Feed_Token (C, Code);
else
End_Token (C, TK_IDENT);
goto Start_Over;
end if;
when LX_NUMBER =>
if R.Is_Digit(Code) then
Feed_Token (C, Code);
else
End_Token (C, TK_IDENT); -- TODO: change this
goto Start_Over;
end if;
end case;
end Feed_Char_Code;
procedure Feed (C: in out Compiler; Data: in S.Rune_Array) is
begin
for i in Data'Range loop
Feed_Char_Code (C, R.To_Code(Data(i)));
if C.St.Top > 0 then
declare
Ch: Standard.Character;
begin
while not Ada.Text_IO.End_Of_File(C.St.Items(C.St.Top).Handle) loop
Ada.Text_IO.Get (C.St.Items(C.St.Top).Handle, Ch);
Feed_Char_Code (C, Standard.Character'Pos(Ch));
--if inclusion stack is not Empty???
end loop;
end;
end if;
end loop;
end Feed;
procedure End_Feed (C: in out Compiler) is
begin
Feed_Char_Code (C, R.P.EOF);
end End_Feed;
end H3.Compilers;