------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- O U T P U T -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2005, 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. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package contains low level output routines used by the compiler -- for writing error messages and informational output. It is also used -- by the debug source file output routines (see Sprintf.Print_Eol). with Hostparm; use Hostparm; with Types; use Types; package Output is pragma Elaborate_Body; type Output_Proc is access procedure (S : String); -- This type is used for the Set_Special_Output procedure. If this -- procedure is called, then instead of lines being written to -- standard error or standard output, a call is made to the given -- procedure for each line, passing the line with an end of line -- character (which is a single ASCII.LF character, even in systems -- which normally use CR/LF or some other sequence for line end). ----------------- -- Subprograms -- ----------------- procedure Set_Special_Output (P : Output_Proc); -- Sets subsequent output to call procedure P. If P is null, then -- the call cancels the effect of a previous call, reverting the -- output to standard error or standard output depending on the -- mode at the time of previous call. Any exception generated by -- by calls to P is simply propagated to the caller of the routine -- causing the write operation. procedure Cancel_Special_Output; -- Cancels the effect of a call to Set_Special_Output, if any. -- The output is then directed to standard error or standard output -- depending on the last call to Set_Standard_Error or Set_Standard_Output. -- It is never an error to call Cancel_Special_Output. It has the same -- effect as calling Set_Special_Output (null). procedure Set_Standard_Error; -- Sets subsequent output to appear on the standard error file (whatever -- that might mean for the host operating system, if anything) when -- no special output is in effect. When a special output is in effect, -- the output will appear on standard error only after special output -- has been cancelled. procedure Set_Standard_Output; -- Sets subsequent output to appear on the standard output file (whatever -- that might mean for the host operating system, if anything) when -- no special output is in effect. When a special output is in effect, -- the output will appear on standard output only after special output -- has been cancelled. Output to standard output is the default mode -- before any call to either of the Set procedures. procedure Write_Char (C : Character); -- Write one character to the standard output file. Note that the -- character should not be LF or CR (use Write_Eol for end of line) procedure Write_Erase_Char (C : Character); -- If last character in buffer matches C, erase it, otherwise no effect procedure Write_Eol; -- Write an end of line (whatever is required by the system in use, -- e.g. CR/LF for DOS, or LF for Unix) to the standard output file. -- This routine also empties the line buffer, actually writing it -- to the file. Note that Write_Eol is the only routine that causes -- any actual output to be written. procedure Write_Int (Val : Int); -- Write an integer value with no leading blanks or zeroes. Negative -- values are preceded by a minus sign). procedure Write_Str (S : String); -- Write a string of characters to the standard output file. Note that -- end of line is handled separately using WRITE_EOL, so the string -- should not contain either of the characters LF or CR, but it may -- contain horizontal tab characters. procedure Write_Line (S : String); -- Equivalent to Write_Str (S) followed by Write_Eol; function Column return Pos; pragma Inline (Column); -- Returns the number of the column about to be written (e.g. a value -- of 1 means the current line is empty). ------------------------- -- Buffer Save/Restore -- ------------------------- -- This facility allows the current line buffer to be saved and restored type Saved_Output_Buffer is private; -- Type used for Save/Restore_Buffer Buffer_Max : constant := Hostparm.Max_Line_Length; -- Maximal size of a buffered output line function Save_Output_Buffer return Saved_Output_Buffer; -- Save current line buffer and reset line buffer to empty procedure Restore_Output_Buffer (S : Saved_Output_Buffer); -- Restore previously saved output buffer. The value in S is not affected -- so it is legtimate to restore a buffer more than once. -------------------------- -- Debugging Procedures -- -------------------------- -- The following procedures are intended only for debugging purposes, -- for temporary insertion into the text in environments where a debugger -- is not available. They all have non-standard very short lower case -- names, precisely to make sure that they are only used for debugging! procedure w (C : Character); -- Dump quote, character quote, followed by line return procedure w (S : String); -- Dump string followed by line return procedure w (V : Int); -- Dump integer followed by line return procedure w (B : Boolean); -- Dump Boolean followed by line return procedure w (L : String; C : Character); -- Dump contents of string followed by blank, quote, character, quote procedure w (L : String; S : String); -- Dump two strings separated by blanks, followed by line return procedure w (L : String; V : Int); -- Dump contents of string followed by blank, integer, line return procedure w (L : String; B : Boolean); -- Dump contents of string followed by blank, Boolean, line return private -- Note: the following buffer and column position are maintained by the -- subprograms defined in this package, and cannot be directly modified or -- accessed by a client. Buffer : String (1 .. Buffer_Max + 1); for Buffer'Alignment use 4; -- Buffer used to build output line. We do line buffering because it -- is needed for the support of the debug-generated-code option (-gnatD). -- Historically it was first added because on VMS, line buffering is -- needed with certain file formats. So in any case line buffering must -- be retained for this purpose, even if other reasons disappear. Note -- any attempt to write more output to a line than can fit in the buffer -- will be silently ignored. The alignment clause improves the efficiency -- of the save/restore procedures. Next_Col : Positive range 1 .. Buffer'Length + 1 := 1; -- Column about to be written type Saved_Output_Buffer is record Buffer : String (1 .. Buffer_Max + 1); Next_Col : Positive; end record; end Output;