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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- S T Y L E G --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2006, 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, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, 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;
Blank_Lines : Nat := 0;
-- Counts number of empty lines seen. Reset to zero if a non-empty line
-- is encountered. Used to check for trailing blank lines in Check_EOF,
-- and for multiple blank lines.
Blank_Line_Location : Source_Ptr;
-- Remembers location of first blank line in a series. Used to issue an
-- appropriate diagnostic if subsequent blank lines or the end of file
-- is encountered.
-----------------------
-- 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
-- Do we need to worry about UTF_32 line terminators here ???
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_EOF --
---------------
-- In check blanks at end mode, check no blank lines precede the EOF
procedure Check_EOF is
begin
if Style_Check_Blank_Lines then
-- We expect one blank line, from the EOF, but no more than one
if Blank_Lines = 2 then
Error_Msg
("(style) blank line not allowed at end of file",
Blank_Line_Location);
elsif Blank_Lines >= 3 then
Error_Msg
("(style) blank lines not allowed at end of file",
Blank_Line_Location);
end if;
end if;
end Check_EOF;
-----------------------------------
-- 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_Max_Length --
---------------------------
-- In check max line length mode (-gnatym), the line length must
-- not exceed the permitted maximum value.
procedure Check_Line_Max_Length (Len : Int) is
begin
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_Max_Length;
---------------------------
-- Check_Line_Terminator --
---------------------------
-- In check blanks at end mode (-gnatyb), lines may not end with a
-- trailing space.
-- In check form feeds mode (-gnatyf), the line terminator may not
-- be either of the characters FF or VT.
-- In check DOS line terminators node (-gnatyd), the line terminator
-- must be a single LF, without a following CR.
procedure Check_Line_Terminator (Len : Int) is
S : Source_Ptr;
L : Int := Len;
-- Length of line (adjusted down for blanks at end of line)
begin
-- Reset count of blank lines if first line
if Get_Logical_Line_Number (Scan_Ptr) = 1 then
Blank_Lines := 0;
end if;
-- 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;
-- Check DOS line terminator (ignore EOF, since we only get called
-- with an EOF if it is the last character in the buffer, and was
-- therefore not present in the sources
if Style_Check_DOS_Line_Terminator then
if Source (Scan_Ptr) = EOF then
null;
elsif Source (Scan_Ptr) /= LF
or else Source (Scan_Ptr + 1) = CR
then
Error_Msg_S ("(style) incorrect line terminator");
end if;
end if;
-- Remove trailing spaces
S := Scan_Ptr;
while L > 0 and then Is_White_Space (Source (S - 1)) loop
S := S - 1;
L := L - 1;
end loop;
-- Issue message for blanks at end of line if option enabled
if Style_Check_Blanks_At_End and then L < Len then
Error_Msg
("(style) trailing spaces not permitted", S);
end if;
-- Deal with empty (blank) line
if L = 0 then
-- Increment blank line count
Blank_Lines := Blank_Lines + 1;
-- If first blank line, record location for later error message
if Blank_Lines = 1 then
Blank_Line_Location := Scan_Ptr;
end if;
-- Non-blank line, check for previous multiple blank lines
else
if Style_Check_Blank_Lines and then Blank_Lines > 1 then
Error_Msg
("(style) multiple blank lines", Blank_Line_Location);
end if;
-- And reset blank line count
Blank_Lines := 0;
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;
-------------------
-- Mode_In_Check --
-------------------
function Mode_In_Check return Boolean is
begin
return Style_Check and Style_Check_Mode_In;
end Mode_In_Check;
-----------------
-- 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;