------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S T Y L E G -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2004 Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT 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 distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This version of the Style package implements the standard GNAT style -- checking rules. For documentation of these rules, see comments on the -- individual procedures. with Casing; use Casing; with Csets; use Csets; with Err_Vars; use Err_Vars; with Opt; use Opt; with Scans; use Scans; with Sinput; use Sinput; with Stylesw; use Stylesw; package body Styleg is use ASCII; ----------------------- -- Local Subprograms -- ----------------------- procedure Check_No_Space_After; -- Checks that there is a non-white space character after the current -- token, or white space followed by a comment, or the end of line. -- Issue error message if not. procedure Check_No_Space_Before; -- Check that token is first token on line, or else is not preceded -- by white space. Signal error of space not allowed if not. function Determine_Token_Casing return Casing_Type; procedure Error_Space_Not_Allowed (S : Source_Ptr); -- Posts an error message indicating that a space is not allowed -- at the given source location. procedure Error_Space_Required (S : Source_Ptr); -- Posts an error message indicating that a space is required at -- the given source location. function Is_White_Space (C : Character) return Boolean; pragma Inline (Is_White_Space); -- Returns True for space, HT, VT or FF, False otherwise procedure Require_Following_Space; pragma Inline (Require_Following_Space); -- Require token to be followed by white space. Used only if in GNAT -- style checking mode. procedure Require_Preceding_Space; pragma Inline (Require_Preceding_Space); -- Require token to be preceded by white space. Used only if in GNAT -- style checking mode. ---------------------- -- Check_Abs_Or_Not -- ---------------------- -- In check tokens mode (-gnatyt), ABS/NOT must be followed by a space procedure Check_Abs_Not is begin if Style_Check_Tokens then if Source (Scan_Ptr) > ' ' then Error_Space_Required (Scan_Ptr); end if; end if; end Check_Abs_Not; ---------------------- -- Check_Apostrophe -- ---------------------- -- Do not allow space before or after apostrophe procedure Check_Apostrophe is begin if Style_Check_Tokens then Check_No_Space_After; end if; end Check_Apostrophe; ----------------- -- Check_Arrow -- ----------------- -- In check tokens mode (-gnatys), arrow must be surrounded by spaces procedure Check_Arrow is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Arrow; -------------------------- -- Check_Attribute_Name -- -------------------------- -- In check attribute casing mode (-gnatya), attribute names must be -- mixed case, i.e. start with an upper case letter, and otherwise -- lower case, except after an underline character. procedure Check_Attribute_Name (Reserved : Boolean) is pragma Warnings (Off, Reserved); begin if Style_Check_Attribute_Casing then if Determine_Token_Casing /= Mixed_Case then Error_Msg_SC ("(style) bad capitalization, mixed case required"); end if; end if; end Check_Attribute_Name; --------------------------- -- Check_Binary_Operator -- --------------------------- -- In check token mode (-gnatyt), binary operators other than the special -- case of exponentiation require surrounding space characters. procedure Check_Binary_Operator is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Binary_Operator; --------------- -- Check_Box -- --------------- -- In check token mode (-gnatyt), box must be preceded by a space or by -- a left parenthesis. Spacing checking on the surrounding tokens takes -- care of the remaining checks. procedure Check_Box is begin if Style_Check_Tokens then if Prev_Token /= Tok_Left_Paren then Require_Preceding_Space; end if; end if; end Check_Box; ----------------- -- Check_Colon -- ----------------- -- In check token mode (-gnatyt), colon must be surrounded by spaces procedure Check_Colon is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Colon; ----------------------- -- Check_Colon_Equal -- ----------------------- -- In check token mode (-gnatyt), := must be surrounded by spaces procedure Check_Colon_Equal is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Colon_Equal; ----------------- -- Check_Comma -- ----------------- -- In check token mode (-gnatyt), comma must be either the first -- token on a line, or be preceded by a non-blank character. -- It must also always be followed by a blank. procedure Check_Comma is begin if Style_Check_Tokens then Check_No_Space_Before; if Source (Scan_Ptr) > ' ' then Error_Space_Required (Scan_Ptr); end if; end if; end Check_Comma; ------------------- -- Check_Comment -- ------------------- -- In check comment mode (-gnatyc) there are several requirements on the -- format of comments. The following are permissible comment formats: -- 1. Any comment that is not at the start of a line, i.e. where the -- initial minuses are not the first non-blank characters on the -- line must have at least one blank after the second minus. -- 2. A row of all minuses of any length is permitted (see procedure -- box above in the source of this routine). -- 3. A comment line starting with two minuses and a space, and ending -- with a space and two minuses. Again see the procedure title box -- immediately above in the source. -- 4. A full line comment where two spaces follow the two minus signs. -- This is the normal comment format in GNAT style, as typified by -- the comments you are reading now. -- 5. A full line comment where the first character after the second -- minus is a special character, i.e. a character in the ASCII -- range 16#21#..16#2F# or 16#3A#..16#3F#. This allows special -- comments, such as those generated by gnatprep, or those that -- appear in the SPARK annotation language to be accepted. -- -- Note: for GNAT internal files (-gnatg switch set on for the -- compilation), the only special sequence recognized and allowed -- is --! as generated by gnatprep. procedure Check_Comment is S : Source_Ptr; C : Character; function Is_Box_Comment return Boolean; -- Returns True if the last two characters on the line are -- which -- characterizes a box comment (as for example follows this spec). -------------------- -- Is_Box_Comment -- -------------------- function Is_Box_Comment return Boolean is S : Source_Ptr; begin S := Scan_Ptr + 3; while Source (S) not in Line_Terminator loop S := S + 1; end loop; return Source (S - 1) = '-' and then Source (S - 2) = '-'; end Is_Box_Comment; -- Start of processing for Check_Comment begin -- Can never have a non-blank character preceding the first minus if Style_Check_Comments then if Scan_Ptr > Source_First (Current_Source_File) and then Source (Scan_Ptr - 1) > ' ' then Error_Msg_S ("(style) space required"); end if; end if; -- For a comment that is not at the start of the line, the only -- requirement is that we cannot have a non-blank character after -- the second minus sign. if Scan_Ptr /= First_Non_Blank_Location then if Style_Check_Comments then if Source (Scan_Ptr + 2) > ' ' then Error_Msg ("(style) space required", Scan_Ptr + 2); end if; end if; return; -- Case of a comment that is at the start of a line else -- First check, must be in appropriately indented column if Style_Check_Indentation /= 0 then if Start_Column rem Style_Check_Indentation /= 0 then Error_Msg_S ("(style) bad column"); return; end if; end if; -- If we are not checking comments, nothing to do if not Style_Check_Comments then return; end if; -- Case of not followed by a blank. Usually wrong, but there are -- some exceptions that we permit. if Source (Scan_Ptr + 2) /= ' ' then C := Source (Scan_Ptr + 2); -- Case of -- all on its own on a line is OK if C < ' ' then return; end if; -- Case of --x, x special character is OK (gnatprep/SPARK/etc.) -- This is not permitted in internal GNAT implementation units -- except for the case of --! as used by gnatprep output. if GNAT_Mode then if C = '!' then return; end if; else if Character'Pos (C) in 16#21# .. 16#2F# or else Character'Pos (C) in 16#3A# .. 16#3F# then return; end if; end if; -- The only other case in which we allow a character after -- the -- other than a space is when we have a row of minus -- signs (case of header lines for a box comment for example). S := Scan_Ptr + 2; while Source (S) >= ' ' loop if Source (S) /= '-' then if Is_Box_Comment then Error_Space_Required (Scan_Ptr + 2); else Error_Msg ("(style) two spaces required", Scan_Ptr + 2); end if; return; end if; S := S + 1; end loop; -- If we are followed by a blank, then the comment is OK if the -- character following this blank is another blank or a format -- effector. elsif Source (Scan_Ptr + 3) <= ' ' then return; -- Here is the case where we only have one blank after the two -- minus signs, which is an error unless the line ends with two -- minus signs, the case of a box comment. elsif not Is_Box_Comment then Error_Space_Required (Scan_Ptr + 3); end if; end if; end Check_Comment; ------------------- -- Check_Dot_Dot -- ------------------- -- In check token mode (-gnatyt), colon must be surrounded by spaces procedure Check_Dot_Dot is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Dot_Dot; ----------------------------------- -- Check_Exponentiation_Operator -- ----------------------------------- -- No spaces are required for the ** operator in GNAT style check mode procedure Check_Exponentiation_Operator is begin null; end Check_Exponentiation_Operator; -------------- -- Check_HT -- -------------- -- In check horizontal tab mode (-gnatyh), tab characters are not allowed procedure Check_HT is begin if Style_Check_Horizontal_Tabs then Error_Msg_S ("(style) horizontal tab not allowed"); end if; end Check_HT; ----------------------- -- Check_Indentation -- ----------------------- -- In check indentation mode (-gnatyn for n a digit), a new statement or -- declaration is required to start in a column that is a multiple of the -- indentiation amount. procedure Check_Indentation is begin if Style_Check_Indentation /= 0 then if Token_Ptr = First_Non_Blank_Location and then Start_Column rem Style_Check_Indentation /= 0 then Error_Msg_SC ("(style) bad indentation"); end if; end if; end Check_Indentation; ---------------------- -- Check_Left_Paren -- ---------------------- -- In tone check mode (-gnatyt), left paren must not be preceded by an -- identifier character or digit (a separating space is required) and -- may never be followed by a space. procedure Check_Left_Paren is begin if Style_Check_Tokens then if Token_Ptr > Source_First (Current_Source_File) and then Identifier_Char (Source (Token_Ptr - 1)) then Error_Space_Required (Token_Ptr); end if; Check_No_Space_After; end if; end Check_Left_Paren; --------------------------- -- Check_Line_Terminator -- --------------------------- -- In check blanks at end mode (-gnatyb), lines may not end with a -- trailing space. -- In check max line length mode (-gnatym), the line length must -- not exceed the permitted maximum value. -- In check form feeds mode (-gnatyf), the line terminator may not -- be either of the characters FF or VT. procedure Check_Line_Terminator (Len : Int) is S : Source_Ptr; begin -- Check FF/VT terminators if Style_Check_Form_Feeds then if Source (Scan_Ptr) = ASCII.FF then Error_Msg_S ("(style) form feed not allowed"); elsif Source (Scan_Ptr) = ASCII.VT then Error_Msg_S ("(style) vertical tab not allowed"); end if; end if; -- We are now possibly going to check for trailing spaces and maximum -- line length. There is no point in doing this if the current line is -- empty. It is actually wrong in the case of trailing spaces, because -- we scan backwards for this purpose, so we would end up looking at a -- different line, or even at invalid buffer locations if we have the -- first source line at hand. if Len = 0 then return; end if; -- Check trailing space if Style_Check_Blanks_At_End then if Scan_Ptr >= First_Non_Blank_Location then if Is_White_Space (Source (Scan_Ptr - 1)) then S := Scan_Ptr - 1; while Is_White_Space (Source (S - 1)) loop S := S - 1; end loop; Error_Msg ("(style) trailing spaces not permitted", S); end if; end if; end if; -- Check max line length if Style_Check_Max_Line_Length then if Len > Style_Max_Line_Length then Error_Msg ("(style) this line is too long", Current_Line_Start + Source_Ptr (Style_Max_Line_Length)); end if; end if; end Check_Line_Terminator; -------------------------- -- Check_No_Space_After -- -------------------------- procedure Check_No_Space_After is S : Source_Ptr; begin if Is_White_Space (Source (Scan_Ptr)) then -- Allow one or more spaces if followed by comment S := Scan_Ptr + 1; loop if Source (S) = '-' and then Source (S + 1) = '-' then return; elsif Is_White_Space (Source (S)) then S := S + 1; else exit; end if; end loop; Error_Space_Not_Allowed (Scan_Ptr); end if; end Check_No_Space_After; --------------------------- -- Check_No_Space_Before -- --------------------------- procedure Check_No_Space_Before is begin if Token_Ptr > First_Non_Blank_Location and then Source (Token_Ptr - 1) <= ' ' then Error_Space_Not_Allowed (Token_Ptr - 1); end if; end Check_No_Space_Before; ----------------------- -- Check_Pragma_Name -- ----------------------- -- In check pragma casing mode (-gnatyp), pragma names must be mixed -- case, i.e. start with an upper case letter, and otherwise lower case, -- except after an underline character. procedure Check_Pragma_Name is begin if Style_Check_Pragma_Casing then if Determine_Token_Casing /= Mixed_Case then Error_Msg_SC ("(style) bad capitalization, mixed case required"); end if; end if; end Check_Pragma_Name; ----------------------- -- Check_Right_Paren -- ----------------------- -- In check tokens mode (-gnatyt), right paren must never be preceded by -- a space unless it is the initial non-blank character on the line. procedure Check_Right_Paren is begin if Style_Check_Tokens then Check_No_Space_Before; end if; end Check_Right_Paren; --------------------- -- Check_Semicolon -- --------------------- -- In check tokens mode (-gnatyt), semicolon does not permit a preceding -- space and a following space is required. procedure Check_Semicolon is begin if Style_Check_Tokens then Check_No_Space_Before; if Source (Scan_Ptr) > ' ' then Error_Space_Required (Scan_Ptr); end if; end if; end Check_Semicolon; ---------------- -- Check_Then -- ---------------- -- In check if then layout mode (-gnatyi), we expect a THEN keyword -- to appear either on the same line as the IF, or on a separate line -- after multiple conditions. In any case, it may not appear on the -- line immediately following the line with the IF. procedure Check_Then (If_Loc : Source_Ptr) is begin if Style_Check_If_Then_Layout then if Get_Physical_Line_Number (Token_Ptr) = Get_Physical_Line_Number (If_Loc) + 1 then Error_Msg_SC ("(style) misplaced THEN"); end if; end if; end Check_Then; ------------------------------- -- Check_Unary_Plus_Or_Minus -- ------------------------------- -- In check tokem mode (-gnatyt), unary plus or minus must not be -- followed by a space. procedure Check_Unary_Plus_Or_Minus is begin if Style_Check_Tokens then Check_No_Space_After; end if; end Check_Unary_Plus_Or_Minus; ------------------------ -- Check_Vertical_Bar -- ------------------------ -- In check token mode (-gnatyt), vertical bar must be surrounded by spaces procedure Check_Vertical_Bar is begin if Style_Check_Tokens then Require_Preceding_Space; Require_Following_Space; end if; end Check_Vertical_Bar; ----------------------- -- Check_Xtra_Parens -- ----------------------- procedure Check_Xtra_Parens (Loc : Source_Ptr) is begin if Style_Check_Xtra_Parens then Error_Msg ("redundant parentheses?", Loc); end if; end Check_Xtra_Parens; ---------------------------- -- Determine_Token_Casing -- ---------------------------- function Determine_Token_Casing return Casing_Type is begin return Determine_Casing (Source (Token_Ptr .. Scan_Ptr - 1)); end Determine_Token_Casing; ----------------------------- -- Error_Space_Not_Allowed -- ----------------------------- procedure Error_Space_Not_Allowed (S : Source_Ptr) is begin Error_Msg ("(style) space not allowed", S); end Error_Space_Not_Allowed; -------------------------- -- Error_Space_Required -- -------------------------- procedure Error_Space_Required (S : Source_Ptr) is begin Error_Msg ("(style) space required", S); end Error_Space_Required; -------------------- -- Is_White_Space -- -------------------- function Is_White_Space (C : Character) return Boolean is begin return C = ' ' or else C = HT; end Is_White_Space; ----------------- -- No_End_Name -- ----------------- -- In check end/exit labels mode (-gnatye), always require the name of -- a subprogram or package to be present on the END, so this is an error. procedure No_End_Name (Name : Node_Id) is begin if Style_Check_End_Labels then Error_Msg_Node_1 := Name; Error_Msg_SP ("(style) `END &` required"); end if; end No_End_Name; ------------------ -- No_Exit_Name -- ------------------ -- In check end/exit labels mode (-gnatye), always require the name of -- the loop to be present on the EXIT when exiting a named loop. procedure No_Exit_Name (Name : Node_Id) is begin if Style_Check_End_Labels then Error_Msg_Node_1 := Name; Error_Msg_SP ("(style) `EXIT &` required"); end if; end No_Exit_Name; ---------------------------- -- Non_Lower_Case_Keyword -- ---------------------------- -- In check casing mode (-gnatyk), reserved keywords must be be spelled -- in all lower case (excluding keywords range, access, delta and digits -- used as attribute designators). procedure Non_Lower_Case_Keyword is begin if Style_Check_Keyword_Casing then Error_Msg_SC ("(style) reserved words must be all lower case"); end if; end Non_Lower_Case_Keyword; ----------------------------- -- Require_Following_Space -- ----------------------------- procedure Require_Following_Space is begin if Source (Scan_Ptr) > ' ' then Error_Space_Required (Scan_Ptr); end if; end Require_Following_Space; ----------------------------- -- Require_Preceding_Space -- ----------------------------- procedure Require_Preceding_Space is begin if Token_Ptr > Source_First (Current_Source_File) and then Source (Token_Ptr - 1) > ' ' then Error_Space_Required (Token_Ptr); end if; end Require_Preceding_Space; --------------------- -- RM_Column_Check -- --------------------- function RM_Column_Check return Boolean is begin return Style_Check and Style_Check_Layout; end RM_Column_Check; end Styleg;