| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME COMPONENTS -- |
| -- -- |
| -- G N A T . I O _ A U X -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1995-2010, AdaCore -- |
| -- -- |
| -- 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 Interfaces.C_Streams; use Interfaces.C_Streams; |
| |
| package body GNAT.IO_Aux is |
| |
| Buflen : constant := 2000; |
| -- Buffer length. Works for any non-zero value, larger values take |
| -- more stack space, smaller values require more recursion. |
| |
| ----------------- |
| -- File_Exists -- |
| ----------------- |
| |
| function File_Exists (Name : String) return Boolean |
| is |
| Namestr : aliased String (1 .. Name'Length + 1); |
| -- Name as given with ASCII.NUL appended |
| |
| begin |
| Namestr (1 .. Name'Length) := Name; |
| Namestr (Name'Length + 1) := ASCII.NUL; |
| return file_exists (Namestr'Address) /= 0; |
| end File_Exists; |
| |
| -------------- |
| -- Get_Line -- |
| -------------- |
| |
| -- Current_Input case |
| |
| function Get_Line return String is |
| Buffer : String (1 .. Buflen); |
| -- Buffer to read in chunks of remaining line. Will work with any |
| -- size buffer. We choose a length so that most of the time no |
| -- recursion will be required. |
| |
| Last : Natural; |
| |
| begin |
| Ada.Text_IO.Get_Line (Buffer, Last); |
| |
| -- If the buffer is not full, then we are all done |
| |
| if Last < Buffer'Last then |
| return Buffer (1 .. Last); |
| |
| -- Otherwise, we still have characters left on the line. Note that |
| -- as specified by (RM A.10.7(19)) the end of line is not skipped |
| -- in this case, even if we are right at it now. |
| |
| else |
| return Buffer & GNAT.IO_Aux.Get_Line; |
| end if; |
| end Get_Line; |
| |
| -- Case of reading from a specified file. Note that we could certainly |
| -- share code between these two versions, but these are very short |
| -- routines, and we may as well aim for maximum speed, cutting out an |
| -- intermediate call (calls returning string may be somewhat slow) |
| |
| function Get_Line (File : Ada.Text_IO.File_Type) return String is |
| Buffer : String (1 .. Buflen); |
| Last : Natural; |
| |
| begin |
| Ada.Text_IO.Get_Line (File, Buffer, Last); |
| |
| if Last < Buffer'Last then |
| return Buffer (1 .. Last); |
| else |
| return Buffer & Get_Line (File); |
| end if; |
| end Get_Line; |
| |
| end GNAT.IO_Aux; |
