gcc/testsuite/ada/acats/tests/cxa/cxaa013.a

   1 -- CXAA013.A
   2 --
   3 --                             Grant of Unlimited Rights
   4 --
   5 --     Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
   6 --     F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained
   7 --     unlimited rights in the software and documentation contained herein.
   8 --     Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making
   9 --     this public release, the Government intends to confer upon all
  10 --     recipients unlimited rights  equal to those held by the Government.
  11 --     These rights include rights to use, duplicate, release or disclose the
  12 --     released technical data and computer software in whole or in part, in
  13 --     any manner and for any purpose whatsoever, and to have or permit others
  14 --     to do so.
  15 --
  16 --                                    DISCLAIMER
  17 --
  18 --     ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
  19 --     DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED
  20 --     WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
  21 --     SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE
  22 --     OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A
  23 --     PARTICULAR PURPOSE OF SAID MATERIAL.
  24 --*
  25 --
  26 -- OBJECTIVE:
  27 --      Check that the exception Mode_Error is raised when an attempt is made
  28 --      to skip a line or page using the predefined Skip_Line and Skip_Page
  29 --      procedures on a text file with mode Append_File.
  30 --
  31 -- TEST DESCRIPTION:
  32 --      A scenario is created that demonstrates the potential for the
  33 --      incorrect usage of predefined text processing subprograms, which
  34 --      results in the raising of a Mode_Error exception.
  35 --      A count is kept to ensure that each anticipated exception is in fact
  36 --      raised and handled properly.
  37 --
  38 -- APPLICABILITY CRITERIA:
  39 --      This test is applicable only to implementations that support text
  40 --      files.
  41 --
  42 --
  43 -- CHANGE HISTORY:
  44 --      06 Dec 94   SAIC    ACVC 2.0
  45 --      28 Feb 97   PWB.CTA Allowed for non-support of some IO operations
  46 --!
  47
  48 with Ada.Text_IO;
  49 with Report;
  50
  51 procedure CXAA013 is
  52    use Ada;
  53    Text_File     : Text_IO.File_Type;
  54    Text_Filename : constant String :=
  55                               Report.Legal_File_Name ( Nam => "CXAA013" );
  56    Incomplete : exception;
  57
  58 begin
  59
  60          Report.Test ("CXAA013", "Check that the exception Mode_Error is " &
  61                                  "raised when an attempt is made to skip " &
  62                                  "a line or page using the predefined "    &
  63                                  "Skip_Line and Skip_Page procedures on "  &
  64                                  "a text file with mode Append_File");
  65
  66          Test_for_Text_IO_Support:
  67          begin
  68
  69 -- An application creates a text file with mode Append_File.
  70 -- Use_Error will be raised if Text_IO operations or external files are not
  71 -- supported.
  72
  73             Text_IO.Create (Text_File, Text_IO.Append_File, Text_Filename);
  74
  75    exception
  76
  77        when Text_IO.Use_Error | Text_IO.Name_Error =>
  78           Report.Not_Applicable
  79              ( "Files not supported - Create as Append_File for Text_IO" );
  80           raise Incomplete;
  81
  82    end Test_for_Text_IO_Support;
  83
  84 -- The application writes some amount of data to the file.
  85
  86    Text_IO.Put_Line (Text_File, "Data entered into the file");
  87
  88    Operational_Test_Block:
  89    declare
  90       TC_Number_Of_Forced_Mode_Errors : constant Natural := 2;
  91       TC_Mode_Errors : Natural := 0;
  92    begin
  93
  94       Test_for_Skip_Line:
  95       declare
  96          TC_Spacing : constant Text_IO.Count := 3;
  97       begin
  98
  99 -- During the course of its processing, the application may attempt to
 100 -- invoke the Skip_Line procedure on a file that is currently in Append_File
 101 -- mode (instead of the anticipated In_File mode).  This results in the
 102 -- raising of Mode_Error.
 103
 104          Text_IO.Skip_Line (Text_File, TC_Spacing);
 105          Report.Failed ("Exception not raised by Skip_Line");
 106
 107 -- An exception handler present within the application handles the exception
 108 -- and processing can continue.
 109
 110       exception
 111          when Text_IO.Mode_Error =>
 112             TC_Mode_Errors := TC_Mode_Errors + 1;
 113          when others =>
 114             Report.Failed("Exception in Skip_Line processing");
 115       end Test_for_Skip_Line;
 116
 117       Test_for_Skip_Page:
 118       begin
 119
 120 -- Again, during the course of its processing, the application incorrectly
 121 -- assumes that the file mode is In_File, this time attempting to call the
 122 -- Skip_Page procedure for the file (that is currently in Append_File mode).
 123
 124          Text_IO.Skip_Page (Text_File);
 125          Report.Failed ("Exception not raised by Skip_Page");
 126
 127 -- Once again, an exception handler present within the application handles
 128 -- the exception and processing continues.
 129
 130       exception
 131          when Text_IO.Mode_Error =>
 132             TC_Mode_Errors := TC_Mode_Errors + 1;
 133          when others =>
 134             Report.Failed("Exception in Skip_Page processing");
 135       end Test_for_Skip_Page;
 136
 137       if (TC_Mode_Errors /= TC_Number_Of_Forced_Mode_Errors) then
 138          Report.Failed ("Incorrect number of exceptions handled");
 139       end if;
 140
 141    end Operational_Test_Block;
 142
 143    Deletion:
 144    begin
 145       -- Delete the external file.
 146       if Text_IO.Is_Open (Text_File) then
 147          Text_IO.Delete (Text_File);
 148       else
 149          Text_IO.Open (Text_File, Text_IO.In_File, Text_Filename);
 150          Text_IO.Delete (Text_File);
 151       end if;
 152    exception
 153       when others =>
 154          Report.Failed
 155             ( "Delete not properly implemented for Text_IO" );
 156    end Deletion;
 157
 158    Report.Result;
 159
 160 exception
 161    when Incomplete =>
 162       Report.Result;
 163    when others     =>
 164       Report.Failed ( "Unexpected exception" );
 165       Report.Result;
 166
 167 end CXAA013;