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------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- A D A . T E X T _ I O -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2009, 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 3, 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. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- <http://www.gnu.org/licenses/>. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Ada.Streams; use Ada.Streams; with Interfaces.C_Streams; use Interfaces.C_Streams; with System.File_IO; with System.CRTL; with System.WCh_Cnv; use System.WCh_Cnv; with System.WCh_Con; use System.WCh_Con; with Ada.Unchecked_Conversion; with Ada.Unchecked_Deallocation; pragma Elaborate_All (System.File_IO); -- Needed because of calls to Chain_File in package body elaboration package body Ada.Text_IO is package FIO renames System.File_IO; subtype AP is FCB.AFCB_Ptr; function To_FCB is new Ada.Unchecked_Conversion (File_Mode, FCB.File_Mode); function To_TIO is new Ada.Unchecked_Conversion (FCB.File_Mode, File_Mode); use type FCB.File_Mode; use type System.CRTL.size_t; WC_Encoding : Character; pragma Import (C, WC_Encoding, "__gl_wc_encoding"); -- Default wide character encoding Err_Name : aliased String := "*stderr" & ASCII.NUL; In_Name : aliased String := "*stdin" & ASCII.NUL; Out_Name : aliased String := "*stdout" & ASCII.NUL; -- Names of standard files -- -- Use "preallocated" strings to avoid calling "new" during the elaboration -- of the run time. This is needed in the tasking case to avoid calling -- Task_Lock too early. A filename is expected to end with a null character -- in the runtime, here the null characters are added just to have a -- correct filename length. -- -- Note: the names for these files are bogus, and probably it would be -- better for these files to have no names, but the ACVC tests insist! -- We use names that are bound to fail in open etc. Null_Str : aliased constant String := ""; -- Used as form string for standard files ----------------------- -- Local Subprograms -- ----------------------- function Get_Upper_Half_Char (C : Character; File : File_Type) return Character; -- This function is shared by Get and Get_Immediate to extract an encoded -- upper half character value from the given File. The first byte has -- already been read and is passed in C. The character value is returned as -- the result, and the file pointer is bumped past the character. -- Constraint_Error is raised if the encoded value is outside the bounds of -- type Character. function Get_Upper_Half_Char_Immed (C : Character; File : File_Type) return Character; -- This routine is identical to Get_Upper_Half_Char, except that the reads -- are done in Get_Immediate mode (i.e. without waiting for a line return). function Getc (File : File_Type) return int; -- Gets next character from file, which has already been checked for being -- in read status, and returns the character read if no error occurs. The -- result is EOF if the end of file was read. function Getc_Immed (File : File_Type) return int; -- This routine is identical to Getc, except that the read is done in -- Get_Immediate mode (i.e. without waiting for a line return). function Has_Upper_Half_Character (Item : String) return Boolean; -- Returns True if any of the characters is in the range 16#80#-16#FF# function Nextc (File : File_Type) return int; -- Returns next character from file without skipping past it (i.e. it is a -- combination of Getc followed by an Ungetc). procedure Put_Encoded (File : File_Type; Char : Character); -- Called to output a character Char to the given File, when the encoding -- method for the file is other than brackets, and Char is upper half. procedure Putc (ch : int; File : File_Type); -- Outputs the given character to the file, which has already been checked -- for being in output status. Device_Error is raised if the character -- cannot be written. procedure Set_WCEM (File : in out File_Type); -- Called by Open and Create to set the wide character encoding method for -- the file, processing a WCEM form parameter if one is present. File is -- IN OUT because it may be closed in case of an error. procedure Terminate_Line (File : File_Type); -- If the file is in Write_File or Append_File mode, and the current line -- is not terminated, then a line terminator is written using New_Line. -- Note that there is no Terminate_Page routine, because the page mark at -- the end of the file is implied if necessary. procedure Ungetc (ch : int; File : File_Type); -- Pushes back character into stream, using ungetc. The caller has checked -- that the file is in read status. Device_Error is raised if the character -- cannot be pushed back. An attempt to push back and end of file character -- (EOF) is ignored. ------------------- -- AFCB_Allocate -- ------------------- function AFCB_Allocate (Control_Block : Text_AFCB) return FCB.AFCB_Ptr is pragma Unreferenced (Control_Block); begin return new Text_AFCB; end AFCB_Allocate; ---------------- -- AFCB_Close -- ---------------- procedure AFCB_Close (File : not null access Text_AFCB) is begin -- If the file being closed is one of the current files, then close -- the corresponding current file. It is not clear that this action -- is required (RM A.10.3(23)) but it seems reasonable, and besides -- ACVC test CE3208A expects this behavior. if File_Type (File) = Current_In then Current_In := null; elsif File_Type (File) = Current_Out then Current_Out := null; elsif File_Type (File) = Current_Err then Current_Err := null; end if; Terminate_Line (File_Type (File)); end AFCB_Close; --------------- -- AFCB_Free -- --------------- procedure AFCB_Free (File : not null access Text_AFCB) is type FCB_Ptr is access all Text_AFCB; FT : FCB_Ptr := FCB_Ptr (File); procedure Free is new Ada.Unchecked_Deallocation (Text_AFCB, FCB_Ptr); begin Free (FT); end AFCB_Free; ----------- -- Close -- ----------- procedure Close (File : in out File_Type) is begin FIO.Close (AP (File)'Unrestricted_Access); end Close; --------- -- Col -- --------- -- Note: we assume that it is impossible in practice for the column -- to exceed the value of Count'Last, i.e. no check is required for -- overflow raising layout error. function Col (File : File_Type) return Positive_Count is begin FIO.Check_File_Open (AP (File)); return File.Col; end Col; function Col return Positive_Count is begin return Col (Current_Out); end Col; ------------ -- Create -- ------------ procedure Create (File : in out File_Type; Mode : File_Mode := Out_File; Name : String := ""; Form : String := "") is Dummy_File_Control_Block : Text_AFCB; pragma Warnings (Off, Dummy_File_Control_Block); -- Yes, we know this is never assigned a value, only the tag -- is used for dispatching purposes, so that's expected. begin FIO.Open (File_Ptr => AP (File), Dummy_FCB => Dummy_File_Control_Block, Mode => To_FCB (Mode), Name => Name, Form => Form, Amethod => 'T', Creat => True, Text => True); File.Self := File; Set_WCEM (File); end Create; ------------------- -- Current_Error -- ------------------- function Current_Error return File_Type is begin return Current_Err; end Current_Error; function Current_Error return File_Access is begin return Current_Err.Self'Access; end Current_Error; ------------------- -- Current_Input -- ------------------- function Current_Input return File_Type is begin return Current_In; end Current_Input; function Current_Input return File_Access is begin return Current_In.Self'Access; end Current_Input; -------------------- -- Current_Output -- -------------------- function Current_Output return File_Type is begin return Current_Out; end Current_Output; function Current_Output return File_Access is begin return Current_Out.Self'Access; end Current_Output; ------------ -- Delete -- ------------ procedure Delete (File : in out File_Type) is begin FIO.Delete (AP (File)'Unrestricted_Access); end Delete; ----------------- -- End_Of_File -- ----------------- function End_Of_File (File : File_Type) return Boolean is ch : int; begin FIO.Check_Read_Status (AP (File)); if File.Before_Upper_Half_Character then return False; elsif File.Before_LM then if File.Before_LM_PM then return Nextc (File) = EOF; end if; else ch := Getc (File); if ch = EOF then return True; elsif ch /= LM then Ungetc (ch, File); return False; else -- ch = LM File.Before_LM := True; end if; end if; -- Here we are just past the line mark with Before_LM set so that we -- do not have to try to back up past the LM, thus avoiding the need -- to back up more than one character. ch := Getc (File); if ch = EOF then return True; elsif ch = PM and then File.Is_Regular_File then File.Before_LM_PM := True; return Nextc (File) = EOF; -- Here if neither EOF nor PM followed end of line else Ungetc (ch, File); return False; end if; end End_Of_File; function End_Of_File return Boolean is begin return End_Of_File (Current_In); end End_Of_File; ----------------- -- End_Of_Line -- ----------------- function End_Of_Line (File : File_Type) return Boolean is ch : int; begin FIO.Check_Read_Status (AP (File)); if File.Before_Upper_Half_Character then return False; elsif File.Before_LM then return True; else ch := Getc (File); if ch = EOF then return True; else Ungetc (ch, File); return (ch = LM); end if; end if; end End_Of_Line; function End_Of_Line return Boolean is begin return End_Of_Line (Current_In); end End_Of_Line; ----------------- -- End_Of_Page -- ----------------- function End_Of_Page (File : File_Type) return Boolean is ch : int; begin FIO.Check_Read_Status (AP (File)); if not File.Is_Regular_File then return False; elsif File.Before_Upper_Half_Character then return False; elsif File.Before_LM then if File.Before_LM_PM then return True; end if; else ch := Getc (File); if ch = EOF then return True; elsif ch /= LM then Ungetc (ch, File); return False; else -- ch = LM File.Before_LM := True; end if; end if; -- Here we are just past the line mark with Before_LM set so that we -- do not have to try to back up past the LM, thus avoiding the need -- to back up more than one character. ch := Nextc (File); return ch = PM or else ch = EOF; end End_Of_Page; function End_Of_Page return Boolean is begin return End_Of_Page (Current_In); end End_Of_Page; -------------- -- EOF_Char -- -------------- function EOF_Char return Integer is begin return EOF; end EOF_Char; ----------- -- Flush -- ----------- procedure Flush (File : File_Type) is begin FIO.Flush (AP (File)); end Flush; procedure Flush is begin Flush (Current_Out); end Flush; ---------- -- Form -- ---------- function Form (File : File_Type) return String is begin return FIO.Form (AP (File)); end Form; --------- -- Get -- --------- procedure Get (File : File_Type; Item : out Character) is ch : int; begin FIO.Check_Read_Status (AP (File)); if File.Before_Upper_Half_Character then File.Before_Upper_Half_Character := False; Item := File.Saved_Upper_Half_Character; elsif File.Before_LM then File.Before_LM := False; File.Col := 1; if File.Before_LM_PM then File.Line := 1; File.Page := File.Page + 1; File.Before_LM_PM := False; else File.Line := File.Line + 1; end if; end if; loop ch := Getc (File); if ch = EOF then raise End_Error; elsif ch = LM then File.Line := File.Line + 1; File.Col := 1; elsif ch = PM and then File.Is_Regular_File then File.Page := File.Page + 1; File.Line := 1; else Item := Character'Val (ch); File.Col := File.Col + 1; return; end if; end loop; end Get; procedure Get (Item : out Character) is begin Get (Current_In, Item); end Get; procedure Get (File : File_Type; Item : out String) is ch : int; J : Natural; begin FIO.Check_Read_Status (AP (File)); if File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; File.Col := 1; if File.Before_LM_PM then File.Line := 1; File.Page := File.Page + 1; File.Before_LM_PM := False; else File.Line := File.Line + 1; end if; end if; J := Item'First; while J <= Item'Last loop ch := Getc (File); if ch = EOF then raise End_Error; elsif ch = LM then File.Line := File.Line + 1; File.Col := 1; elsif ch = PM and then File.Is_Regular_File then File.Page := File.Page + 1; File.Line := 1; else Item (J) := Character'Val (ch); J := J + 1; File.Col := File.Col + 1; end if; end loop; end Get; procedure Get (Item : out String) is begin Get (Current_In, Item); end Get; ------------------- -- Get_Immediate -- ------------------- procedure Get_Immediate (File : File_Type; Item : out Character) is ch : int; begin FIO.Check_Read_Status (AP (File)); if File.Before_Upper_Half_Character then File.Before_Upper_Half_Character := False; Item := File.Saved_Upper_Half_Character; elsif File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; Item := Character'Val (LM); else ch := Getc_Immed (File); if ch = EOF then raise End_Error; else Item := (if not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method) then Character'Val (ch) else Get_Upper_Half_Char_Immed (Character'Val (ch), File)); end if; end if; end Get_Immediate; procedure Get_Immediate (Item : out Character) is begin Get_Immediate (Current_In, Item); end Get_Immediate; procedure Get_Immediate (File : File_Type; Item : out Character; Available : out Boolean) is ch : int; end_of_file : int; avail : int; procedure getc_immediate_nowait (stream : FILEs; ch : out int; end_of_file : out int; avail : out int); pragma Import (C, getc_immediate_nowait, "getc_immediate_nowait"); begin FIO.Check_Read_Status (AP (File)); Available := True; if File.Before_Upper_Half_Character then File.Before_Upper_Half_Character := False; Item := File.Saved_Upper_Half_Character; elsif File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; Item := Character'Val (LM); else getc_immediate_nowait (File.Stream, ch, end_of_file, avail); if ferror (File.Stream) /= 0 then raise Device_Error; elsif end_of_file /= 0 then raise End_Error; elsif avail = 0 then Available := False; Item := ASCII.NUL; else Available := True; Item := (if Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method) then Character'Val (ch) else Get_Upper_Half_Char_Immed (Character'Val (ch), File)); end if; end if; end Get_Immediate; procedure Get_Immediate (Item : out Character; Available : out Boolean) is begin Get_Immediate (Current_In, Item, Available); end Get_Immediate; -------------- -- Get_Line -- -------------- procedure Get_Line (File : File_Type; Item : out String; Last : out Natural) is ch : int; begin FIO.Check_Read_Status (AP (File)); Last := Item'First - 1; -- Immediate exit for null string, this is a case in which we do not -- need to test for end of file and we do not skip a line mark under -- any circumstances. if Last >= Item'Last then return; end if; -- Here we have at least one character, if we are immediately before -- a line mark, then we will just skip past it storing no characters. if File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; -- Otherwise we need to read some characters else ch := Getc (File); -- If we are at the end of file now, it means we are trying to -- skip a file terminator and we raise End_Error (RM A.10.7(20)) if ch = EOF then raise End_Error; end if; -- Loop through characters. Don't bother if we hit a page mark, -- since in normal files, page marks can only follow line marks -- in any case and we only promise to treat the page nonsense -- correctly in the absense of such rogue page marks. loop -- Exit the loop if read is terminated by encountering line mark exit when ch = LM; -- Otherwise store the character, note that we know that ch is -- something other than LM or EOF. It could possibly be a page -- mark if there is a stray page mark in the middle of a line, -- but this is not an official page mark in any case, since -- official page marks can only follow a line mark. The whole -- page business is pretty much nonsense anyway, so we do not -- want to waste time trying to make sense out of non-standard -- page marks in the file! This means that the behavior of -- Get_Line is different from repeated Get of a character, but -- that's too bad. We only promise that page numbers etc make -- sense if the file is formatted in a standard manner. -- Note: we do not adjust the column number because it is quicker -- to adjust it once at the end of the operation than incrementing -- it each time around the loop. Last := Last + 1; Item (Last) := Character'Val (ch); -- All done if the string is full, this is the case in which -- we do not skip the following line mark. We need to adjust -- the column number in this case. if Last = Item'Last then File.Col := File.Col + Count (Item'Length); return; end if; -- Otherwise read next character. We also exit from the loop if -- we read an end of file. This is the case where the last line -- is not terminated with a line mark, and we consider that there -- is an implied line mark in this case (this is a non-standard -- file, but it is nice to treat it reasonably). ch := Getc (File); exit when ch = EOF; end loop; end if; -- We have skipped past, but not stored, a line mark. Skip following -- page mark if one follows, but do not do this for a non-regular -- file (since otherwise we get annoying wait for an extra character) File.Line := File.Line + 1; File.Col := 1; if File.Before_LM_PM then File.Line := 1; File.Before_LM_PM := False; File.Page := File.Page + 1; elsif File.Is_Regular_File then ch := Getc (File); if ch = PM and then File.Is_Regular_File then File.Line := 1; File.Page := File.Page + 1; else Ungetc (ch, File); end if; end if; end Get_Line; procedure Get_Line (Item : out String; Last : out Natural) is begin Get_Line (Current_In, Item, Last); end Get_Line; function Get_Line (File : File_Type) return String is Buffer : String (1 .. 500); Last : Natural; function Get_Rest (S : String) return String; -- This is a recursive function that reads the rest of the line and -- returns it. S is the part read so far. -------------- -- Get_Rest -- -------------- function Get_Rest (S : String) return String is -- Each time we allocate a buffer the same size as what we have -- read so far. This limits us to a logarithmic number of calls -- to Get_Rest and also ensures only a linear use of stack space. Buffer : String (1 .. S'Length); Last : Natural; begin Get_Line (File, Buffer, Last); declare R : constant String := S & Buffer (1 .. Last); begin if Last < Buffer'Last then return R; else return Get_Rest (R); end if; end; end Get_Rest; -- Start of processing for Get_Line begin Get_Line (File, Buffer, Last); if Last < Buffer'Last then return Buffer (1 .. Last); else return Get_Rest (Buffer (1 .. Last)); end if; end Get_Line; function Get_Line return String is begin return Get_Line (Current_In); end Get_Line; ------------------------- -- Get_Upper_Half_Char -- ------------------------- function Get_Upper_Half_Char (C : Character; File : File_Type) return Character is Result : Wide_Character; function In_Char return Character; -- Function used to obtain additional characters it the wide character -- sequence is more than one character long. function WC_In is new Char_Sequence_To_Wide_Char (In_Char); ------------- -- In_Char -- ------------- function In_Char return Character is ch : constant Integer := Getc (File); begin if ch = EOF then raise End_Error; else return Character'Val (ch); end if; end In_Char; -- Start of processing for Get_Upper_Half_Char begin Result := WC_In (C, File.WC_Method); if Wide_Character'Pos (Result) > 16#FF# then raise Constraint_Error with "invalid wide character in Text_'I'O input"; else return Character'Val (Wide_Character'Pos (Result)); end if; end Get_Upper_Half_Char; ------------------------------- -- Get_Upper_Half_Char_Immed -- ------------------------------- function Get_Upper_Half_Char_Immed (C : Character; File : File_Type) return Character is Result : Wide_Character; function In_Char return Character; -- Function used to obtain additional characters it the wide character -- sequence is more than one character long. function WC_In is new Char_Sequence_To_Wide_Char (In_Char); ------------- -- In_Char -- ------------- function In_Char return Character is ch : constant Integer := Getc_Immed (File); begin if ch = EOF then raise End_Error; else return Character'Val (ch); end if; end In_Char; -- Start of processing for Get_Upper_Half_Char_Immed begin Result := WC_In (C, File.WC_Method); if Wide_Character'Pos (Result) > 16#FF# then raise Constraint_Error with "invalid wide character in Text_'I'O input"; else return Character'Val (Wide_Character'Pos (Result)); end if; end Get_Upper_Half_Char_Immed; ---------- -- Getc -- ---------- function Getc (File : File_Type) return int is ch : int; begin ch := fgetc (File.Stream); if ch = EOF and then ferror (File.Stream) /= 0 then raise Device_Error; else return ch; end if; end Getc; ---------------- -- Getc_Immed -- ---------------- function Getc_Immed (File : File_Type) return int is ch : int; end_of_file : int; procedure getc_immediate (stream : FILEs; ch : out int; end_of_file : out int); pragma Import (C, getc_immediate, "getc_immediate"); begin FIO.Check_Read_Status (AP (File)); if File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; ch := LM; else getc_immediate (File.Stream, ch, end_of_file); if ferror (File.Stream) /= 0 then raise Device_Error; elsif end_of_file /= 0 then return EOF; end if; end if; return ch; end Getc_Immed; ------------------------------ -- Has_Upper_Half_Character -- ------------------------------ function Has_Upper_Half_Character (Item : String) return Boolean is begin for J in Item'Range loop if Character'Pos (Item (J)) >= 16#80# then return True; end if; end loop; return False; end Has_Upper_Half_Character; ------------------------------- -- Initialize_Standard_Files -- ------------------------------- procedure Initialize_Standard_Files is begin Standard_Err.Stream := stderr; Standard_Err.Name := Err_Name'Access; Standard_Err.Form := Null_Str'Unrestricted_Access; Standard_Err.Mode := FCB.Out_File; Standard_Err.Is_Regular_File := is_regular_file (fileno (stderr)) /= 0; Standard_Err.Is_Temporary_File := False; Standard_Err.Is_System_File := True; Standard_Err.Is_Text_File := True; Standard_Err.Access_Method := 'T'; Standard_Err.Self := Standard_Err; Standard_Err.WC_Method := Default_WCEM; Standard_In.Stream := stdin; Standard_In.Name := In_Name'Access; Standard_In.Form := Null_Str'Unrestricted_Access; Standard_In.Mode := FCB.In_File; Standard_In.Is_Regular_File := is_regular_file (fileno (stdin)) /= 0; Standard_In.Is_Temporary_File := False; Standard_In.Is_System_File := True; Standard_In.Is_Text_File := True; Standard_In.Access_Method := 'T'; Standard_In.Self := Standard_In; Standard_In.WC_Method := Default_WCEM; Standard_Out.Stream := stdout; Standard_Out.Name := Out_Name'Access; Standard_Out.Form := Null_Str'Unrestricted_Access; Standard_Out.Mode := FCB.Out_File; Standard_Out.Is_Regular_File := is_regular_file (fileno (stdout)) /= 0; Standard_Out.Is_Temporary_File := False; Standard_Out.Is_System_File := True; Standard_Out.Is_Text_File := True; Standard_Out.Access_Method := 'T'; Standard_Out.Self := Standard_Out; Standard_Out.WC_Method := Default_WCEM; FIO.Make_Unbuffered (AP (Standard_Out)); FIO.Make_Unbuffered (AP (Standard_Err)); end Initialize_Standard_Files; ------------- -- Is_Open -- ------------- function Is_Open (File : File_Type) return Boolean is begin return FIO.Is_Open (AP (File)); end Is_Open; ---------- -- Line -- ---------- -- Note: we assume that it is impossible in practice for the line -- to exceed the value of Count'Last, i.e. no check is required for -- overflow raising layout error. function Line (File : File_Type) return Positive_Count is begin FIO.Check_File_Open (AP (File)); return File.Line; end Line; function Line return Positive_Count is begin return Line (Current_Out); end Line; ----------------- -- Line_Length -- ----------------- function Line_Length (File : File_Type) return Count is begin FIO.Check_Write_Status (AP (File)); return File.Line_Length; end Line_Length; function Line_Length return Count is begin return Line_Length (Current_Out); end Line_Length; ---------------- -- Look_Ahead -- ---------------- procedure Look_Ahead (File : File_Type; Item : out Character; End_Of_Line : out Boolean) is ch : int; begin FIO.Check_Read_Status (AP (File)); -- If we are logically before a line mark, we can return immediately if File.Before_LM then End_Of_Line := True; Item := ASCII.NUL; -- If we are before an upper half character just return it (this can -- happen if there are two calls to Look_Ahead in a row). elsif File.Before_Upper_Half_Character then End_Of_Line := False; Item := File.Saved_Upper_Half_Character; -- Otherwise we must read a character from the input stream else ch := Getc (File); if ch = LM or else ch = EOF or else (ch = PM and then File.Is_Regular_File) then End_Of_Line := True; Ungetc (ch, File); Item := ASCII.NUL; -- Case where character obtained does not represent the start of an -- encoded sequence so it stands for itself and we can unget it with -- no difficulty. elsif not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method) then End_Of_Line := False; Ungetc (ch, File); Item := Character'Val (ch); -- For the start of an encoding, we read the character using the -- Get_Upper_Half_Char routine. It will occupy more than one byte -- so we can't put it back with ungetc. Instead we save it in the -- control block, setting a flag that everyone interested in reading -- characters must test before reading the stream. else Item := Get_Upper_Half_Char (Character'Val (ch), File); End_Of_Line := False; File.Saved_Upper_Half_Character := Item; File.Before_Upper_Half_Character := True; end if; end if; end Look_Ahead; procedure Look_Ahead (Item : out Character; End_Of_Line : out Boolean) is begin Look_Ahead (Current_In, Item, End_Of_Line); end Look_Ahead; ---------- -- Mode -- ---------- function Mode (File : File_Type) return File_Mode is begin return To_TIO (FIO.Mode (AP (File))); end Mode; ---------- -- Name -- ---------- function Name (File : File_Type) return String is begin return FIO.Name (AP (File)); end Name; -------------- -- New_Line -- -------------- procedure New_Line (File : File_Type; Spacing : Positive_Count := 1) is begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not Spacing'Valid then raise Constraint_Error; end if; FIO.Check_Write_Status (AP (File)); for K in 1 .. Spacing loop Putc (LM, File); File.Line := File.Line + 1; if File.Page_Length /= 0 and then File.Line > File.Page_Length then Putc (PM, File); File.Line := 1; File.Page := File.Page + 1; end if; end loop; File.Col := 1; end New_Line; procedure New_Line (Spacing : Positive_Count := 1) is begin New_Line (Current_Out, Spacing); end New_Line; -------------- -- New_Page -- -------------- procedure New_Page (File : File_Type) is begin FIO.Check_Write_Status (AP (File)); if File.Col /= 1 or else File.Line = 1 then Putc (LM, File); end if; Putc (PM, File); File.Page := File.Page + 1; File.Line := 1; File.Col := 1; end New_Page; procedure New_Page is begin New_Page (Current_Out); end New_Page; ----------- -- Nextc -- ----------- function Nextc (File : File_Type) return int is ch : int; begin ch := fgetc (File.Stream); if ch = EOF then if ferror (File.Stream) /= 0 then raise Device_Error; end if; else if ungetc (ch, File.Stream) = EOF then raise Device_Error; end if; end if; return ch; end Nextc; ---------- -- Open -- ---------- procedure Open (File : in out File_Type; Mode : File_Mode; Name : String; Form : String := "") is Dummy_File_Control_Block : Text_AFCB; pragma Warnings (Off, Dummy_File_Control_Block); -- Yes, we know this is never assigned a value, only the tag -- is used for dispatching purposes, so that's expected. begin FIO.Open (File_Ptr => AP (File), Dummy_FCB => Dummy_File_Control_Block, Mode => To_FCB (Mode), Name => Name, Form => Form, Amethod => 'T', Creat => False, Text => True); File.Self := File; Set_WCEM (File); end Open; ---------- -- Page -- ---------- -- Note: we assume that it is impossible in practice for the page -- to exceed the value of Count'Last, i.e. no check is required for -- overflow raising layout error. function Page (File : File_Type) return Positive_Count is begin FIO.Check_File_Open (AP (File)); return File.Page; end Page; function Page return Positive_Count is begin return Page (Current_Out); end Page; ----------------- -- Page_Length -- ----------------- function Page_Length (File : File_Type) return Count is begin FIO.Check_Write_Status (AP (File)); return File.Page_Length; end Page_Length; function Page_Length return Count is begin return Page_Length (Current_Out); end Page_Length; --------- -- Put -- --------- procedure Put (File : File_Type; Item : Character) is begin FIO.Check_Write_Status (AP (File)); if File.Line_Length /= 0 and then File.Col > File.Line_Length then New_Line (File); end if; -- If lower half character, or brackets encoding, output directly if Character'Pos (Item) < 16#80# or else File.WC_Method = WCEM_Brackets then if fputc (Character'Pos (Item), File.Stream) = EOF then raise Device_Error; end if; -- Case of upper half character with non-brackets encoding else Put_Encoded (File, Item); end if; File.Col := File.Col + 1; end Put; procedure Put (Item : Character) is begin FIO.Check_Write_Status (AP (Current_Out)); if Current_Out.Line_Length /= 0 and then Current_Out.Col > Current_Out.Line_Length then New_Line (Current_Out); end if; -- If lower half character, or brackets encoding, output directly if Character'Pos (Item) < 16#80# or else Default_WCEM = WCEM_Brackets then if fputc (Character'Pos (Item), Current_Out.Stream) = EOF then raise Device_Error; end if; -- Case of upper half character with non-brackets encoding else Put_Encoded (Current_Out, Item); end if; Current_Out.Col := Current_Out.Col + 1; end Put; --------- -- Put -- --------- procedure Put (File : File_Type; Item : String) is begin FIO.Check_Write_Status (AP (File)); -- Only have something to do if string is non-null if Item'Length > 0 then -- If we have bounded lines, or if the file encoding is other than -- Brackets and the string has at least one upper half character, -- then output the string character by character. if File.Line_Length /= 0 or else (File.WC_Method /= WCEM_Brackets and then Has_Upper_Half_Character (Item)) then for J in Item'Range loop Put (File, Item (J)); end loop; -- Otherwise we can output the entire string at once. Note that if -- there are LF or FF characters in the string, we do not bother to -- count them as line or page terminators. else FIO.Write_Buf (AP (File), Item'Address, Item'Length); File.Col := File.Col + Item'Length; end if; end if; end Put; procedure Put (Item : String) is begin Put (Current_Out, Item); end Put; ----------------- -- Put_Encoded -- ----------------- procedure Put_Encoded (File : File_Type; Char : Character) is procedure Out_Char (C : Character); -- Procedure to output one character of an upper half encoded sequence procedure WC_Out is new Wide_Char_To_Char_Sequence (Out_Char); -------------- -- Out_Char -- -------------- procedure Out_Char (C : Character) is begin Putc (Character'Pos (C), File); end Out_Char; -- Start of processing for Put_Encoded begin WC_Out (Wide_Character'Val (Character'Pos (Char)), File.WC_Method); end Put_Encoded; -------------- -- Put_Line -- -------------- procedure Put_Line (File : File_Type; Item : String) is Ilen : Natural := Item'Length; Istart : Natural := Item'First; begin FIO.Check_Write_Status (AP (File)); -- If we have bounded lines, or if the file encoding is other than -- Brackets and the string has at least one upper half character, then -- output the string character by character. if File.Line_Length /= 0 or else (File.WC_Method /= WCEM_Brackets and then Has_Upper_Half_Character (Item)) then for J in Item'Range loop Put (File, Item (J)); end loop; New_Line (File); return; end if; -- Normal case where we do not need to output character by character -- We setup a single string that has the necessary terminators and -- then write it with a single call. The reason for doing this is -- that it gives better behavior for the use of Put_Line in multi- -- tasking programs, since often the OS will treat the entire put -- operation as an atomic operation. -- We only do this if the message is 512 characters or less in length, -- since otherwise Put_Line would use an unbounded amount of stack -- space and could cause undetected stack overflow. If we have a -- longer string, then output the first part separately to avoid this. if Ilen > 512 then FIO.Write_Buf (AP (File), Item'Address, size_t (Ilen - 512)); Istart := Istart + Ilen - 512; Ilen := 512; end if; -- Now prepare the string with its terminator declare Buffer : String (1 .. Ilen + 2); Plen : size_t; begin Buffer (1 .. Ilen) := Item (Istart .. Item'Last); Buffer (Ilen + 1) := Character'Val (LM); if File.Page_Length /= 0 and then File.Line > File.Page_Length then Buffer (Ilen + 2) := Character'Val (PM); Plen := size_t (Ilen) + 2; File.Line := 1; File.Page := File.Page + 1; else Plen := size_t (Ilen) + 1; File.Line := File.Line + 1; end if; FIO.Write_Buf (AP (File), Buffer'Address, Plen); File.Col := 1; end; end Put_Line; procedure Put_Line (Item : String) is begin Put_Line (Current_Out, Item); end Put_Line; ---------- -- Putc -- ---------- procedure Putc (ch : int; File : File_Type) is begin if fputc (ch, File.Stream) = EOF then raise Device_Error; end if; end Putc; ---------- -- Read -- ---------- -- This is the primitive Stream Read routine, used when a Text_IO file -- is treated directly as a stream using Text_IO.Streams.Stream. procedure Read (File : in out Text_AFCB; Item : out Stream_Element_Array; Last : out Stream_Element_Offset) is Discard_ch : int; pragma Warnings (Off, Discard_ch); begin -- Need to deal with Before_Upper_Half_Character ??? if File.Mode /= FCB.In_File then raise Mode_Error; end if; -- Deal with case where our logical and physical position do not match -- because of being after an LM or LM-PM sequence when in fact we are -- logically positioned before it. if File.Before_LM then -- If we are before a PM, then it is possible for a stream read -- to leave us after the LM and before the PM, which is a bit -- odd. The easiest way to deal with this is to unget the PM, -- so we are indeed positioned between the characters. This way -- further stream read operations will work correctly, and the -- effect on text processing is a little weird, but what can -- be expected if stream and text input are mixed this way? if File.Before_LM_PM then Discard_ch := ungetc (PM, File.Stream); File.Before_LM_PM := False; end if; File.Before_LM := False; Item (Item'First) := Stream_Element (Character'Pos (ASCII.LF)); if Item'Length = 1 then Last := Item'Last; else Last := Item'First + Stream_Element_Offset (fread (buffer => Item'Address, index => size_t (Item'First + 1), size => 1, count => Item'Length - 1, stream => File.Stream)); end if; return; end if; -- Now we do the read. Since this is a text file, it is normally in -- text mode, but stream data must be read in binary mode, so we -- temporarily set binary mode for the read, resetting it after. -- These calls have no effect in a system (like Unix) where there is -- no distinction between text and binary files. set_binary_mode (fileno (File.Stream)); Last := Item'First + Stream_Element_Offset (fread (Item'Address, 1, Item'Length, File.Stream)) - 1; if Last < Item'Last then if ferror (File.Stream) /= 0 then raise Device_Error; end if; end if; set_text_mode (fileno (File.Stream)); end Read; ----------- -- Reset -- ----------- procedure Reset (File : in out File_Type; Mode : File_Mode) is begin -- Don't allow change of mode for current file (RM A.10.2(5)) if (File = Current_In or else File = Current_Out or else File = Current_Error) and then To_FCB (Mode) /= File.Mode then raise Mode_Error; end if; Terminate_Line (File); FIO.Reset (AP (File)'Unrestricted_Access, To_FCB (Mode)); File.Page := 1; File.Line := 1; File.Col := 1; File.Line_Length := 0; File.Page_Length := 0; File.Before_LM := False; File.Before_LM_PM := False; end Reset; procedure Reset (File : in out File_Type) is begin Terminate_Line (File); FIO.Reset (AP (File)'Unrestricted_Access); File.Page := 1; File.Line := 1; File.Col := 1; File.Line_Length := 0; File.Page_Length := 0; File.Before_LM := False; File.Before_LM_PM := False; end Reset; ------------- -- Set_Col -- ------------- procedure Set_Col (File : File_Type; To : Positive_Count) is ch : int; begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not To'Valid then raise Constraint_Error; end if; FIO.Check_File_Open (AP (File)); -- Output case if Mode (File) >= Out_File then -- Error if we attempt to set Col to a value greater than the -- maximum permissible line length. if File.Line_Length /= 0 and then To > File.Line_Length then raise Layout_Error; end if; -- If we are behind current position, then go to start of new line if To < File.Col then New_Line (File); end if; -- Loop to output blanks till we are at the required column while File.Col < To loop Put (File, ' '); end loop; -- Input case else -- If we are logically before a LM, but physically after it, the -- file position still reflects the position before the LM, so eat -- it now and adjust the file position appropriately. if File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; File.Line := File.Line + 1; File.Col := 1; end if; -- Loop reading characters till we get one at the required Col value loop -- Read next character. The reason we have to read ahead is to -- skip formatting characters, the effect of Set_Col is to set -- us to a real character with the right Col value, and format -- characters don't count. ch := Getc (File); -- Error if we hit an end of file if ch = EOF then raise End_Error; -- If line mark, eat it and adjust file position elsif ch = LM then File.Line := File.Line + 1; File.Col := 1; -- If recognized page mark, eat it, and adjust file position elsif ch = PM and then File.Is_Regular_File then File.Page := File.Page + 1; File.Line := 1; File.Col := 1; -- Otherwise this is the character we are looking for, so put it -- back in the input stream (we have not adjusted the file -- position yet, so everything is set right after this ungetc). elsif To = File.Col then Ungetc (ch, File); return; -- Keep skipping characters if we are not there yet, updating the -- file position past the skipped character. else File.Col := File.Col + 1; end if; end loop; end if; end Set_Col; procedure Set_Col (To : Positive_Count) is begin Set_Col (Current_Out, To); end Set_Col; --------------- -- Set_Error -- --------------- procedure Set_Error (File : File_Type) is begin FIO.Check_Write_Status (AP (File)); Current_Err := File; end Set_Error; --------------- -- Set_Input -- --------------- procedure Set_Input (File : File_Type) is begin FIO.Check_Read_Status (AP (File)); Current_In := File; end Set_Input; -------------- -- Set_Line -- -------------- procedure Set_Line (File : File_Type; To : Positive_Count) is begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not To'Valid then raise Constraint_Error; end if; FIO.Check_File_Open (AP (File)); if To = File.Line then return; end if; if Mode (File) >= Out_File then if File.Page_Length /= 0 and then To > File.Page_Length then raise Layout_Error; end if; if To < File.Line then New_Page (File); end if; while File.Line < To loop New_Line (File); end loop; else while To /= File.Line loop Skip_Line (File); end loop; end if; end Set_Line; procedure Set_Line (To : Positive_Count) is begin Set_Line (Current_Out, To); end Set_Line; --------------------- -- Set_Line_Length -- --------------------- procedure Set_Line_Length (File : File_Type; To : Count) is begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not To'Valid then raise Constraint_Error; end if; FIO.Check_Write_Status (AP (File)); File.Line_Length := To; end Set_Line_Length; procedure Set_Line_Length (To : Count) is begin Set_Line_Length (Current_Out, To); end Set_Line_Length; ---------------- -- Set_Output -- ---------------- procedure Set_Output (File : File_Type) is begin FIO.Check_Write_Status (AP (File)); Current_Out := File; end Set_Output; --------------------- -- Set_Page_Length -- --------------------- procedure Set_Page_Length (File : File_Type; To : Count) is begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not To'Valid then raise Constraint_Error; end if; FIO.Check_Write_Status (AP (File)); File.Page_Length := To; end Set_Page_Length; procedure Set_Page_Length (To : Count) is begin Set_Page_Length (Current_Out, To); end Set_Page_Length; -------------- -- Set_WCEM -- -------------- procedure Set_WCEM (File : in out File_Type) is Start : Natural; Stop : Natural; begin File.WC_Method := WCEM_Brackets; FIO.Form_Parameter (File.Form.all, "wcem", Start, Stop); if Start = 0 then File.WC_Method := WCEM_Brackets; else if Stop = Start then for J in WC_Encoding_Letters'Range loop if File.Form (Start) = WC_Encoding_Letters (J) then File.WC_Method := J; return; end if; end loop; end if; Close (File); raise Use_Error with "invalid WCEM form parameter"; end if; end Set_WCEM; --------------- -- Skip_Line -- --------------- procedure Skip_Line (File : File_Type; Spacing : Positive_Count := 1) is ch : int; begin -- Raise Constraint_Error if out of range value. The reason for this -- explicit test is that we don't want junk values around, even if -- checks are off in the caller. if not Spacing'Valid then raise Constraint_Error; end if; FIO.Check_Read_Status (AP (File)); for L in 1 .. Spacing loop if File.Before_LM then File.Before_LM := False; -- Note that if File.Before_LM_PM is currently set, we also have -- to reset it (because it makes sense for Before_LM_PM to be set -- only when Before_LM is also set). This is done later on in this -- subprogram, as soon as Before_LM_PM has been taken into account -- for the purpose of page and line counts. else ch := Getc (File); -- If at end of file now, then immediately raise End_Error. Note -- that we can never be positioned between a line mark and a page -- mark, so if we are at the end of file, we cannot logically be -- before the implicit page mark that is at the end of the file. -- For the same reason, we do not need an explicit check for a -- page mark. If there is a FF in the middle of a line, the file -- is not in canonical format and we do not care about the page -- numbers for files other than ones in canonical format. if ch = EOF then raise End_Error; end if; -- If not at end of file, then loop till we get to an LM or EOF. -- The latter case happens only in non-canonical files where the -- last line is not terminated by LM, but we don't want to blow -- up for such files, so we assume an implicit LM in this case. loop exit when ch = LM or else ch = EOF; ch := Getc (File); end loop; end if; -- We have got past a line mark, now, for a regular file only, -- see if a page mark immediately follows this line mark and -- if so, skip past the page mark as well. We do not do this -- for non-regular files, since it would cause an undesirable -- wait for an additional character. File.Col := 1; File.Line := File.Line + 1; if File.Before_LM_PM then File.Page := File.Page + 1; File.Line := 1; File.Before_LM_PM := False; elsif File.Is_Regular_File then ch := Getc (File); -- Page mark can be explicit, or implied at the end of the file if (ch = PM or else ch = EOF) and then File.Is_Regular_File then File.Page := File.Page + 1; File.Line := 1; else Ungetc (ch, File); end if; end if; end loop; File.Before_Upper_Half_Character := False; end Skip_Line; procedure Skip_Line (Spacing : Positive_Count := 1) is begin Skip_Line (Current_In, Spacing); end Skip_Line; --------------- -- Skip_Page -- --------------- procedure Skip_Page (File : File_Type) is ch : int; begin FIO.Check_Read_Status (AP (File)); -- If at page mark already, just skip it if File.Before_LM_PM then File.Before_LM := False; File.Before_LM_PM := False; File.Page := File.Page + 1; File.Line := 1; File.Col := 1; return; end if; -- This is a bit tricky, if we are logically before an LM then -- it is not an error if we are at an end of file now, since we -- are not really at it. if File.Before_LM then File.Before_LM := False; File.Before_LM_PM := False; ch := Getc (File); -- Otherwise we do raise End_Error if we are at the end of file now else ch := Getc (File); if ch = EOF then raise End_Error; end if; end if; -- Now we can just rumble along to the next page mark, or to the -- end of file, if that comes first. The latter case happens when -- the page mark is implied at the end of file. loop exit when ch = EOF or else (ch = PM and then File.Is_Regular_File); ch := Getc (File); end loop; File.Page := File.Page + 1; File.Line := 1; File.Col := 1; File.Before_Upper_Half_Character := False; end Skip_Page; procedure Skip_Page is begin Skip_Page (Current_In); end Skip_Page; -------------------- -- Standard_Error -- -------------------- function Standard_Error return File_Type is begin return Standard_Err; end Standard_Error; function Standard_Error return File_Access is begin return Standard_Err'Access; end Standard_Error; -------------------- -- Standard_Input -- -------------------- function Standard_Input return File_Type is begin return Standard_In; end Standard_Input; function Standard_Input return File_Access is begin return Standard_In'Access; end Standard_Input; --------------------- -- Standard_Output -- --------------------- function Standard_Output return File_Type is begin return Standard_Out; end Standard_Output; function Standard_Output return File_Access is begin return Standard_Out'Access; end Standard_Output; -------------------- -- Terminate_Line -- -------------------- procedure Terminate_Line (File : File_Type) is begin FIO.Check_File_Open (AP (File)); -- For file other than In_File, test for needing to terminate last line if Mode (File) /= In_File then -- If not at start of line definition need new line if File.Col /= 1 then New_Line (File); -- For files other than standard error and standard output, we -- make sure that an empty file has a single line feed, so that -- it is properly formatted. We avoid this for the standard files -- because it is too much of a nuisance to have these odd line -- feeds when nothing has been written to the file. -- We also avoid this for files opened in append mode, in -- accordance with (RM A.8.2(10)) elsif (File /= Standard_Err and then File /= Standard_Out) and then (File.Line = 1 and then File.Page = 1) and then Mode (File) = Out_File then New_Line (File); end if; end if; end Terminate_Line; ------------ -- Ungetc -- ------------ procedure Ungetc (ch : int; File : File_Type) is begin if ch /= EOF then if ungetc (ch, File.Stream) = EOF then raise Device_Error; end if; end if; end Ungetc; ----------- -- Write -- ----------- -- This is the primitive Stream Write routine, used when a Text_IO file -- is treated directly as a stream using Text_IO.Streams.Stream. procedure Write (File : in out Text_AFCB; Item : Stream_Element_Array) is pragma Warnings (Off, File); -- Because in this implementation we don't need IN OUT, we only read function Has_Translated_Characters return Boolean; -- return True if Item array contains a character which will be -- translated under the text file mode. There is only one such -- character under DOS based systems which is character 10. text_translation_required : Boolean; for text_translation_required'Size use Character'Size; pragma Import (C, text_translation_required, "__gnat_text_translation_required"); Siz : constant size_t := Item'Length; ------------------------------- -- Has_Translated_Characters -- ------------------------------- function Has_Translated_Characters return Boolean is begin for K in Item'Range loop if Item (K) = 10 then return True; end if; end loop; return False; end Has_Translated_Characters; Needs_Binary_Write : constant Boolean := text_translation_required and then Has_Translated_Characters; -- Start of processing for Write begin if File.Mode = FCB.In_File then raise Mode_Error; end if; -- Now we do the write. Since this is a text file, it is normally in -- text mode, but stream data must be written in binary mode, so we -- temporarily set binary mode for the write, resetting it after. This -- is done only if needed (i.e. there is some characters in Item which -- needs to be written using the binary mode). -- These calls have no effect in a system (like Unix) where there is -- no distinction between text and binary files. -- Since the character translation is done at the time the buffer is -- written (this is true under Windows) we first flush current buffer -- with text mode if needed. if Needs_Binary_Write then if fflush (File.Stream) = -1 then raise Device_Error; end if; set_binary_mode (fileno (File.Stream)); end if; if fwrite (Item'Address, 1, Siz, File.Stream) /= Siz then raise Device_Error; end if; -- At this point we need to flush the buffer using the binary mode then -- we reset to text mode. if Needs_Binary_Write then if fflush (File.Stream) = -1 then raise Device_Error; end if; set_text_mode (fileno (File.Stream)); end if; end Write; begin -- Initialize Standard Files for J in WC_Encoding_Method loop if WC_Encoding = WC_Encoding_Letters (J) then Default_WCEM := J; end if; end loop; Initialize_Standard_Files; FIO.Chain_File (AP (Standard_In)); FIO.Chain_File (AP (Standard_Out)); FIO.Chain_File (AP (Standard_Err)); end Ada.Text_IO;
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