gcc/ada/sinput-c.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             S I N P U T . C                              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2020, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
  19 -- http://www.gnu.org/licenses for a complete copy of the license.          --
  20 --                                                                          --
  21 -- GNAT was originally developed  by the GNAT team at  New York University. --
  22 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  23 --                                                                          --
  24 ------------------------------------------------------------------------------
  25
  26 with Debug;  use Debug;
  27 with Opt;    use Opt;
  28 with Output; use Output;
  29 with System; use System;
  30
  31 pragma Warnings (Off);
  32 --  This package is used also by gnatcoll
  33 with System.OS_Lib; use System.OS_Lib;
  34 pragma Warnings (On);
  35
  36 package body Sinput.C is
  37
  38    ---------------
  39    -- Load_File --
  40    ---------------
  41
  42    function Load_File (Path : String) return Source_File_Index is
  43       Src  : Source_Buffer_Ptr;
  44       X    : Source_File_Index;
  45       Lo   : Source_Ptr;
  46       Hi   : Source_Ptr;
  47
  48       Source_File_FD : File_Descriptor;
  49       --  The file descriptor for the current source file. A negative value
  50       --  indicates failure to open the specified source file.
  51
  52       Len : Integer;
  53       --  Length of file (assume no more than 2 gigabytes of source)
  54
  55       Actual_Len : Integer;
  56
  57       Path_Id : File_Name_Type;
  58       File_Id : File_Name_Type;
  59
  60    begin
  61       if Path = "" then
  62          return No_Source_File;
  63       end if;
  64
  65       Source_File.Increment_Last;
  66       X := Source_File.Last;
  67
  68       if Debug_Flag_L then
  69          Write_Str ("Sinput.C.Load_File: created source ");
  70          Write_Int (Int (X));
  71          Write_Str (" for ");
  72          Write_Str (Path);
  73          Write_Line ("");
  74       end if;
  75
  76       if X = Source_File.First then
  77          Lo := First_Source_Ptr;
  78       else
  79          Lo := ((Source_File.Table (X - 1).Source_Last + Source_Align) /
  80                   Source_Align) * Source_Align;
  81       end if;
  82
  83       Name_Len := Path'Length;
  84       Name_Buffer (1 .. Name_Len) := Path;
  85       Path_Id := Name_Find;
  86       Name_Buffer (Name_Len + 1) := ASCII.NUL;
  87
  88       --  Open the source FD, note that we open in binary mode, because as
  89       --  documented in the spec, the caller is expected to handle either
  90       --  DOS or Unix mode files, and there is no point in wasting time on
  91       --  text translation when it is not required.
  92
  93       Source_File_FD := Open_Read (Name_Buffer'Address, Binary);
  94
  95       if Source_File_FD = Invalid_FD then
  96          Source_File.Decrement_Last;
  97          return No_Source_File;
  98
  99       end if;
 100
 101       Len := Integer (File_Length (Source_File_FD));
 102
 103       --  Set Hi so that length is one more than the physical length, allowing
 104       --  for the extra EOF character at the end of the buffer
 105
 106       Hi := Lo + Source_Ptr (Len);
 107
 108       --  Do the actual read operation
 109
 110       declare
 111          Var_Ptr : constant Source_Buffer_Ptr_Var :=
 112            new Source_Buffer (Lo .. Hi);
 113          --  Allocate source buffer, allowing extra character at end for EOF
 114
 115       begin
 116          --  Some systems have file types that require one read per line,
 117          --  so read until we get the Len bytes or until there are no more
 118          --  characters.
 119
 120          Hi := Lo;
 121          loop
 122             Actual_Len := Read (Source_File_FD, Var_Ptr (Hi)'Address, Len);
 123             Hi := Hi + Source_Ptr (Actual_Len);
 124             exit when Actual_Len = Len or else Actual_Len <= 0;
 125          end loop;
 126
 127          Var_Ptr (Hi) := EOF;
 128          Src := Var_Ptr.all'Access;
 129       end;
 130
 131       --  Read is complete, close the file and we are done (no need to test
 132       --  status from close, since we have successfully read the file).
 133
 134       Close (Source_File_FD);
 135
 136       --  Get the file name, without path information
 137
 138       declare
 139          Index : Positive := Path'Last;
 140
 141       begin
 142          while Index > Path'First loop
 143             exit when Path (Index - 1) = '/';
 144             exit when Path (Index - 1) = Directory_Separator;
 145             Index := Index - 1;
 146          end loop;
 147
 148          Name_Len := Path'Last - Index + 1;
 149          Name_Buffer (1 .. Name_Len) := Path (Index .. Path'Last);
 150          File_Id := Name_Find;
 151       end;
 152
 153       declare
 154          S : Source_File_Record renames Source_File.Table (X);
 155
 156       begin
 157          S := (Debug_Source_Name   => File_Id,
 158                File_Name           => File_Id,
 159                File_Type           => Config,
 160                First_Mapped_Line   => No_Line_Number,
 161                Full_Debug_Name     => Path_Id,
 162                Full_File_Name      => Path_Id,
 163                Full_Ref_Name       => Path_Id,
 164                Instance            => No_Instance_Id,
 165                Identifier_Casing   => Unknown,
 166                Inlined_Call        => No_Location,
 167                Inlined_Body        => False,
 168                Inherited_Pragma    => False,
 169                Keyword_Casing      => Unknown,
 170                Last_Source_Line    => 1,
 171                License             => Unknown,
 172                Lines_Table         => null,
 173                Lines_Table_Max     => 1,
 174                Logical_Lines_Table => null,
 175                Num_SRef_Pragmas    => 0,
 176                Reference_Name      => File_Id,
 177                Sloc_Adjust         => 0,
 178                Source_Checksum     => 0,
 179                Source_First        => Lo,
 180                Source_Last         => Hi,
 181                Source_Text         => Src,
 182                Template            => No_Source_File,
 183                Unit                => No_Unit,
 184                Time_Stamp          => Empty_Time_Stamp,
 185                Index               => X);
 186
 187          Alloc_Line_Tables (S, Opt.Table_Factor * Alloc.Lines_Initial);
 188          S.Lines_Table (1) := Lo;
 189       end;
 190
 191       Set_Source_File_Index_Table (X);
 192       return X;
 193    end Load_File;
 194
 195 end Sinput.C;