diff mbox series

[Ada] Misleading warning when no read access for source file

Message ID 20170929153607.GA128521@adacore.com
State New
Headers show
Series [Ada] Misleading warning when no read access for source file | expand

Commit Message

Pierre-Marie de Rodat Sept. 29, 2017, 3:36 p.m. UTC 
This patch corrects an issue whereby source files that did not have read
permissions were incorrectly referred to as "not found'. Now, these different
cases are explicitly identified and warned about properly.

------------
-- Source --
------------

--  toto.c

void toto(void)
{
}

--  hello.adb

with Ada.Text_IO; use Ada.Text_IO;
procedure Hello is
begin
   Put_Line ("Hello, world!");
end Hello;

----------------------------
-- Compilation and output --
----------------------------

& chmod a-r hello.adb
& gcc -c hello.adb
& chmod a+r hello.adb
& chmod a-r toto.c
& gcc -c toto.c
& chmod a+r toto.c

no read access for file "hello.adb"
cc1: fatal error: toto.c: Permission denied
compilation terminated.

Tested on x86_64-pc-linux-gnu, committed on trunk

2017-09-29  Justin Squirek  <squirek@adacore.com>

	* ali-util.adb, comperr.adb, errout.adb, fmap.adb, fname-sf.adb,
	frontend.adb, lib-xref-spark_specific.adb, gnat1drv.adb, gnatls.adb,
	lib.adb, lib-load.adb, lib-writ.adb, prepcomp.adb, sinput-d.adb,
	sinput-l.adb, sprint.adb, targparm.adb: Update comparison for checking
	source file status and error message and/or call to Read_Source_File.
	* libgnat/s-os_lib.ads: Add new potential value constant for
	uninitialized file descriptors.
	* osint.adb, osint.ads (Read_Source_File): Add extra parameter to
	return result of IO to encompass a read access failure in addition to a
	file-not-found error.
diff mbox series

Patch

Index: lib.adb
===================================================================
--- lib.adb	(revision 253283)
+++ lib.adb	(working copy)
@@ -626,7 +626,7 @@ 
             Source_File := Get_Source_File_Index (S);
 
             if Unwind_Instances then
-               while Template (Source_File) /= No_Source_File loop
+               while Template (Source_File) > No_Source_File loop
                   Source_File := Template (Source_File);
                end loop;
             end if;
Index: frontend.adb
===================================================================
--- frontend.adb	(revision 253283)
+++ frontend.adb	(working copy)
@@ -126,7 +126,7 @@ 
 
    --  Return immediately if the main source could not be found
 
-   if Sinput.Main_Source_File = No_Source_File then
+   if Sinput.Main_Source_File <= No_Source_File then
       return;
    end if;
 
@@ -167,7 +167,7 @@ 
 
          --  Case of gnat.adc file present
 
-         if Source_gnat_adc /= No_Source_File then
+         if Source_gnat_adc > No_Source_File then
             --  Parse the gnat.adc file for configuration pragmas
 
             Initialize_Scanner (No_Unit, Source_gnat_adc);
@@ -213,7 +213,7 @@ 
 
                   Source_Config_File := Load_Config_File (Config_Name);
 
-                  if Source_Config_File = No_Source_File then
+                  if Source_Config_File <= No_Source_File then
                      Osint.Fail
                        ("cannot find configuration pragmas file "
                         & Config_File_Names (Index).all);
Index: lib-xref-spark_specific.adb
===================================================================
--- lib-xref-spark_specific.adb	(revision 253283)
+++ lib-xref-spark_specific.adb	(working copy)
@@ -249,7 +249,7 @@ 
       --  Source file could be inexistant as a result of an error, if option
       --  gnatQ is used.
 
-      if File = No_Source_File then
+      if File <= No_Source_File then
          return;
       end if;
 
Index: sprint.adb
===================================================================
--- sprint.adb	(revision 253283)
+++ sprint.adb	(working copy)
@@ -3752,7 +3752,7 @@ 
       --  Ignore if there is no current source file, or we're not in dump
       --  source text mode, or if in freeze actions.
 
-      if Current_Source_File /= No_Source_File
+      if Current_Source_File > No_Source_File
         and then Dump_Source_Text
         and then Freeze_Indent = 0
       then
Index: fmap.adb
===================================================================
--- fmap.adb	(revision 253283)
+++ fmap.adb	(working copy)
@@ -175,6 +175,7 @@ 
    ----------------
 
    procedure Initialize (File_Name : String) is
+      FD  : File_Descriptor;
       Src : Source_Buffer_Ptr;
       Hi  : Source_Ptr;
 
@@ -297,10 +298,14 @@ 
 
    begin
       Empty_Tables;
-      Read_Source_File (Name_Enter (File_Name), 1, Hi, Src, Config);
+      Read_Source_File (Name_Enter (File_Name), 1, Hi, Src, FD, Config);
 
       if Null_Source_Buffer_Ptr (Src) then
-         Write_Str ("warning: could not read mapping file """);
+         if FD = Null_FD then
+            Write_Str ("warning: could not locate mapping file """);
+         else
+            Write_Str ("warning: no read access for mapping file """);
+         end if;
          Write_Str (File_Name);
          Write_Line ("""");
          No_Mapping_File := True;
Index: gnatls.adb
===================================================================
--- gnatls.adb	(revision 253283)
+++ gnatls.adb	(working copy)
@@ -2097,6 +2097,7 @@ 
 
    if RTS_Specified = null then
       declare
+         FD   : File_Descriptor;
          Text : Source_Buffer_Ptr;
          Hi   : Source_Ptr;
 
@@ -2104,7 +2105,7 @@ 
          Name_Buffer (1 .. 10) := "system.ads";
          Name_Len := 10;
 
-         Read_Source_File (Name_Find, Lo => 0, Hi => Hi, Src => Text);
+         Read_Source_File (Name_Find, 0, Hi, Text, FD);
 
          if Null_Source_Buffer_Ptr (Text) then
             No_Runtime := True;
Index: libgnat/s-os_lib.ads
===================================================================
--- libgnat/s-os_lib.ads	(revision 253283)
+++ libgnat/s-os_lib.ads	(working copy)
@@ -191,6 +191,9 @@ 
    Invalid_FD : constant File_Descriptor := -1;
    --  File descriptor returned when error in opening/creating file
 
+   Null_FD : constant File_Descriptor := -2;
+   --  Uninitialized file descriptor
+
    procedure Close (FD : File_Descriptor; Status : out Boolean);
    --  Close file referenced by FD. Status is False if the underlying service
    --  failed. Reasons for failure include: disk full, disk quotas exceeded
Index: lib-load.adb
===================================================================
--- lib-load.adb	(revision 253283)
+++ lib-load.adb	(working copy)
@@ -122,7 +122,7 @@ 
 
       --  No change if we did not find the spec
 
-      if X = No_Source_File then
+      if X <= No_Source_File then
          return;
       end if;
 
@@ -326,7 +326,7 @@ 
          Main_Source_File := Load_Source_File (Fname);
          Current_Error_Source_File := Main_Source_File;
 
-         if Main_Source_File /= No_Source_File then
+         if Main_Source_File > No_Source_File then
             Version := Source_Checksum (Main_Source_File);
          else
             --  To avoid emitting a source location (since there is no file),
@@ -334,7 +334,13 @@ 
             --  in errout.adb.
 
             Set_Standard_Error;
-            Write_Str ("file """ & Get_Name_String (Fname) & """ not found");
+            if Main_Source_File = No_Access_To_Source_File then
+               Write_Str ("no read access for file """
+                          & Get_Name_String (Fname) & """");
+            else
+               Write_Str ("file """
+                          & Get_Name_String (Fname) & """ not found");
+            end if;
             Write_Eol;
             Set_Standard_Output;
          end if;
@@ -716,7 +722,7 @@ 
 
          --  File was found
 
-         if Src_Ind /= No_Source_File then
+         if Src_Ind > No_Source_File then
             Units.Table (Unum) :=
               (Cunit             => Empty,
                Cunit_Entity      => Empty,
@@ -824,7 +830,11 @@ 
 
          else
             if Debug_Flag_L then
-               Write_Str ("  file was not found, load failed");
+               if Src_Ind = No_Access_To_Source_File then
+                  Write_Str ("  no read access to file, load failed");
+               else
+                  Write_Str ("  file was not found, load failed");
+               end if;
                Write_Eol;
             end if;
 
@@ -857,7 +867,11 @@ 
 
                else
                   Error_Msg_File_1 := Fname;
-                  Error_Msg ("file{ not found", Load_Msg_Sloc);
+                  if Src_Ind = No_Access_To_Source_File then
+                     Error_Msg ("no read access to file{", Load_Msg_Sloc);
+                  else
+                     Error_Msg ("file{ not found", Load_Msg_Sloc);
+                  end if;
                end if;
 
                Write_Dependency_Chain;
@@ -983,7 +997,7 @@ 
       Unum  : constant Unit_Number_Type := Get_Cunit_Unit_Number (U);
       Fnum  : constant Unit_Number_Type := Get_Cunit_Unit_Number (From);
    begin
-      if Source_Index (Fnum) /= No_Source_File then
+      if Source_Index (Fnum) > No_Source_File then
          Units.Table (Unum).Version :=
            Units.Table (Unum).Version
              xor
Index: comperr.adb
===================================================================
--- comperr.adb	(revision 253283)
+++ comperr.adb	(working copy)
@@ -253,6 +253,7 @@ 
          --  we use the contents of this file at this point.
 
          declare
+            FD  : File_Descriptor;
             Lo  : Source_Ptr;
             Hi  : Source_Ptr;
             Src : Source_Buffer_Ptr;
@@ -261,7 +262,7 @@ 
             Namet.Unlock;
             Name_Buffer (1 .. 12) := "gnat_bug.box";
             Name_Len := 12;
-            Read_Source_File (Name_Enter, 0, Hi, Src);
+            Read_Source_File (Name_Enter, 0, Hi, Src, FD);
 
             --  If we get a Src file, we use it
 
@@ -457,7 +458,7 @@ 
       --  If parsing was not successful, no Main_Unit is available, so return
       --  immediately.
 
-      if Main_Source_File = No_Source_File then
+      if Main_Source_File <= No_Source_File then
          return;
       end if;
 
Index: osint.adb
===================================================================
--- osint.adb	(revision 253283)
+++ osint.adb	(working copy)
@@ -2565,9 +2565,10 @@ 
       Lo  : Source_Ptr;
       Hi  : out Source_Ptr;
       Src : out Source_Buffer_Ptr;
+      FD  : out File_Descriptor;
       T   : File_Type := Source)
    is
-      Source_File_FD : File_Descriptor;
+      --  Source_File_FD : File_Descriptor;
       --  The file descriptor for the current source file. A negative value
       --  indicates failure to open the specified source file.
 
@@ -2594,6 +2595,7 @@ 
             Fail ("Cannot find: " & Name_Buffer (1 .. Name_Len));
          end if;
 
+         FD  := Null_FD;
          Src := null;
          Hi  := No_Location;
          return;
@@ -2607,9 +2609,9 @@ 
       --  DOS or Unix mode files, and there is no point in wasting time on
       --  text translation when it is not required.
 
-      Source_File_FD := Open_Read (Name_Buffer'Address, Binary);
+      FD := Open_Read (Name_Buffer'Address, Binary);
 
-      if Source_File_FD = Invalid_FD then
+      if FD = Invalid_FD then
          Src := null;
          Hi  := No_Location;
          return;
@@ -2645,7 +2647,7 @@ 
 
       --  Prepare to read data from the file
 
-      Len := Integer (File_Length (Source_File_FD));
+      Len := Integer (File_Length (FD));
 
       --  Set Hi so that length is one more than the physical length,
       --  allowing for the extra EOF character at the end of the buffer
@@ -2665,7 +2667,7 @@ 
 
          Hi := Lo;
          loop
-            Actual_Len := Read (Source_File_FD, Var_Ptr (Hi)'Address, Len);
+            Actual_Len := Read (FD, Var_Ptr (Hi)'Address, Len);
             Hi := Hi + Source_Ptr (Actual_Len);
             exit when Actual_Len = Len or else Actual_Len <= 0;
          end loop;
@@ -2676,7 +2678,7 @@ 
 
       --  Read is complete, get time stamp and close file and we are done
 
-      Close (Source_File_FD, Status);
+      Close (FD, Status);
 
       --  The status should never be False. But, if it is, what can we do?
       --  So, we don't test it.
Index: osint.ads
===================================================================
--- osint.ads	(revision 253283)
+++ osint.ads	(working copy)
@@ -401,6 +401,7 @@ 
       Lo  : Source_Ptr;
       Hi  : out Source_Ptr;
       Src : out Source_Buffer_Ptr;
+      FD  : out File_Descriptor;
       T   : File_Type := Source);
    --  Allocates a Source_Buffer of appropriate length and then reads the
    --  entire contents of the source file N into the buffer. The address of
Index: lib-writ.adb
===================================================================
--- lib-writ.adb	(revision 253283)
+++ lib-writ.adb	(working copy)
@@ -1464,7 +1464,7 @@ 
 
             --  Normal case of a unit entry with a source index
 
-            if Sind /= No_Source_File then
+            if Sind > No_Source_File then
                Fname := File_Name (Sind);
 
                --  Ensure that on platforms where the file names are not case
Index: prepcomp.adb
===================================================================
--- prepcomp.adb	(revision 253283)
+++ prepcomp.adb	(working copy)
@@ -6,7 +6,7 @@ 
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 2003-2016, Free Software Foundation, Inc.         --
+--          Copyright (C) 2003-2017, 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- --
@@ -637,7 +637,7 @@ 
             T           : constant Nat               := Total_Errors_Detected;
 
          begin
-            if Deffile = No_Source_File then
+            if Deffile <= No_Source_File then
                Fail ("definition file """
                      & Get_Name_String (N)
                      & """ not found");
Index: gnat1drv.adb
===================================================================
--- gnat1drv.adb	(revision 253283)
+++ gnat1drv.adb	(working copy)
@@ -852,7 +852,7 @@ 
          --  pragma, to be used this way and to cause the body file to be
          --  ignored in this context).
 
-         if Src_Ind /= No_Source_File
+         if Src_Ind > No_Source_File
            and then Source_File_Is_Body (Src_Ind)
          then
             Errout.Finalize (Last_Call => False);
@@ -1065,6 +1065,11 @@ 
                  ("fatal error, run-time library not installed correctly");
                Write_Line ("cannot locate file system.ads");
                raise Unrecoverable_Error;
+            elsif S = No_Access_To_Source_File then
+               Write_Line
+                 ("fatal error, run-time library not installed correctly");
+               Write_Line ("no read access for file system.ads");
+               raise Unrecoverable_Error;
 
             --  Read system.ads successfully, remember its source index
 
@@ -1141,7 +1146,7 @@ 
 
       --  Exit with errors if the main source could not be parsed
 
-      if Sinput.Main_Source_File = No_Source_File then
+      if Sinput.Main_Source_File <= No_Source_File then
          Errout.Finalize (Last_Call => True);
          Errout.Output_Messages;
          Exit_Program (E_Errors);
Index: ali-util.adb
===================================================================
--- ali-util.adb	(revision 253283)
+++ ali-util.adb	(working copy)
@@ -6,7 +6,7 @@ 
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1992-2014, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2017, 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- --
@@ -148,7 +148,7 @@ 
 
       Source_Index := Sinput.C.Load_File (Get_Name_String (Full_Name));
 
-      if Source_Index = No_Source_File then
+      if Source_Index <= No_Source_File then
          return Checksum_Error;
       end if;
 
Index: sinput-d.adb
===================================================================
--- sinput-d.adb	(revision 253283)
+++ sinput-d.adb	(working copy)
@@ -23,10 +23,11 @@ 
 --                                                                          --
 ------------------------------------------------------------------------------
 
-with Debug;   use Debug;
-with Osint;   use Osint;
-with Osint.C; use Osint.C;
-with Output;  use Output;
+with Debug;         use Debug;
+with Osint;         use Osint;
+with Osint.C;       use Osint.C;
+with Output;        use Output;
+with System.OS_Lib; use System.OS_Lib;
 
 package body Sinput.D is
 
@@ -38,6 +39,7 @@ 
    ------------------------
 
    procedure Close_Debug_Source is
+      FD   : File_Descriptor;
       SFR  : Source_File_Record renames Source_File.Table (Dfile);
       Src  : Source_Buffer_Ptr;
    begin
@@ -48,7 +50,7 @@ 
       --  subsequent access.
 
       Read_Source_File
-        (SFR.Full_Debug_Name, SFR.Source_First, SFR.Source_Last, Src);
+        (SFR.Full_Debug_Name, SFR.Source_First, SFR.Source_Last, Src, FD);
       SFR.Source_Text := Src;
       pragma Assert (SFR.Source_Text'First = SFR.Source_First);
       pragma Assert (SFR.Source_Text'Last = SFR.Source_Last);
Index: sinput-l.adb
===================================================================
--- sinput-l.adb	(revision 253283)
+++ sinput-l.adb	(working copy)
@@ -354,6 +354,7 @@ 
      (N : File_Name_Type;
       T : Osint.File_Type) return Source_File_Index
    is
+      FD  : File_Descriptor;
       Src : Source_Buffer_Ptr;
       X   : Source_File_Index;
       Lo  : Source_Ptr;
@@ -411,12 +412,16 @@ 
                   Source_Align) * Source_Align;
       end if;
 
-      Osint.Read_Source_File (N, Lo, Hi, Src, T);
+      Osint.Read_Source_File (N, Lo, Hi, Src, FD, T);
 
       if Null_Source_Buffer_Ptr (Src) then
          Source_File.Decrement_Last;
-         return No_Source_File;
 
+         if FD = Null_FD then
+            return No_Source_File;
+         else
+            return No_Access_To_Source_File;
+         end if;
       else
          if Debug_Flag_L then
             Write_Eol;
Index: targparm.adb
===================================================================
--- targparm.adb	(revision 253283)
+++ targparm.adb	(working copy)
@@ -23,10 +23,11 @@ 
 --                                                                          --
 ------------------------------------------------------------------------------
 
-with Csets;    use Csets;
+with Csets;         use Csets;
 with Opt;
-with Osint;    use Osint;
-with Output;   use Output;
+with Osint;         use Osint;
+with Output;        use Output;
+with System.OS_Lib; use System.OS_Lib;
 
 package body Targparm is
    use ASCII;
@@ -156,6 +157,7 @@ 
       Set_NUA : Set_NUA_Type := null;
       Set_NUP : Set_NUP_Type := null)
    is
+      FD   : File_Descriptor;
       Text : Source_Buffer_Ptr;
       Hi   : Source_Ptr;
 
@@ -167,11 +169,15 @@ 
       Name_Buffer (1 .. 10) := "system.ads";
       Name_Len := 10;
 
-      Read_Source_File (Name_Find, Lo => 0, Hi => Hi, Src => Text);
+      Read_Source_File (Name_Find, 0, Hi, Text, FD);
 
       if Null_Source_Buffer_Ptr (Text) then
          Write_Line ("fatal error, run-time library not installed correctly");
-         Write_Line ("cannot locate file system.ads");
+         if FD = Null_FD then
+            Write_Line ("cannot locate file system.ads");
+         else
+            Write_Line ("no read access for file system.ads");
+         end if;
          raise Unrecoverable_Error;
       end if;
 
Index: fname-sf.adb
===================================================================
--- fname-sf.adb	(revision 253283)
+++ fname-sf.adb	(working copy)
@@ -23,12 +23,13 @@ 
 --                                                                          --
 ------------------------------------------------------------------------------
 
-with Casing;   use Casing;
-with Fname;    use Fname;
-with Fname.UF; use Fname.UF;
-with SFN_Scan; use SFN_Scan;
-with Osint;    use Osint;
-with Types;    use Types;
+with Casing;        use Casing;
+with Fname;         use Fname;
+with Fname.UF;      use Fname.UF;
+with SFN_Scan;      use SFN_Scan;
+with Osint;         use Osint;
+with Types;         use Types;
+with System.OS_Lib; use System.OS_Lib;
 
 with Unchecked_Conversion;
 
@@ -61,11 +62,12 @@ 
    -----------------------------------
 
    procedure Read_Source_File_Name_Pragmas is
+      FD  : File_Descriptor;
       Src : Source_Buffer_Ptr;
       Hi  : Source_Ptr;
 
    begin
-      Read_Source_File (Name_Enter ("gnat.adc"), 1, Hi, Src);
+      Read_Source_File (Name_Enter ("gnat.adc"), 1, Hi, Src, FD);
 
       if not Null_Source_Buffer_Ptr (Src) then
          --  We need to strip off the trailing EOF that was added by
Index: errout.adb
===================================================================
--- errout.adb	(revision 253283)
+++ errout.adb	(working copy)
@@ -1813,7 +1813,7 @@ 
          --  the Main_Source line is unknown (this happens in error situations,
          --  e.g. when integrated preprocessing fails).
 
-         if Main_Source_File /= No_Source_File then
+         if Main_Source_File > No_Source_File then
             Write_Str (" ");
             Write_Int (Num_Source_Lines (Main_Source_File));
 
@@ -1938,7 +1938,7 @@ 
       --  Source_Reference. This ensures outputting the proper name of
       --  the source file in this situation.
 
-      if Main_Source_File = No_Source_File
+      if Main_Source_File <= No_Source_File
         or else Num_SRef_Pragmas (Main_Source_File) /= 0
       then
          Current_Error_Source_File := No_Source_File;
@@ -2045,7 +2045,7 @@ 
 
                   --  Only write the header if Sfile is known
 
-                  if Sfile /= No_Source_File then
+                  if Sfile > No_Source_File then
                      Write_Header (Sfile);
                      Write_Eol;
                   end if;
@@ -2066,7 +2066,7 @@ 
                   --  Only output the listing if Sfile is known, to avoid
                   --  crashing the compiler.
 
-                  if Sfile /= No_Source_File then
+                  if Sfile > No_Source_File then
                      for N in 1 .. Last_Source_Line (Sfile) loop
                         while E /= No_Error_Msg
                           and then Errors.Table (E).Deleted
@@ -2141,7 +2141,7 @@ 
 
          --  Output the header only when Main_Source_File is known
 
-         if Main_Source_File /= No_Source_File then
+         if Main_Source_File > No_Source_File then
             Write_Header (Main_Source_File);
          end if;