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    Types: TextFile
    Names: »B«

└─⟦516dceb10⟧ Bits:30000751 8mm tape, Rational 1000, RCI_VADS
    └─ ⟦9a14c9417⟧ »DATA« 
        └─⟦this⟧ 

TextFile

-- Copyright 1986,1987,1988 Verdix Corporation

WITH System;
USE System;
WITH V_I_Types;
WITH V_I_Sema;
WITH V_I_Time;
WITH V_I_Timeop;
WITH V_Tas;
PACKAGE BODY V_Sema IS

   PRAGMA Suppress (All_Checks);
   PRAGMA Suppress (Exception_Tables);

   Priority_Inheritance_Enabled : Boolean;
   PRAGMA Interface_Name (Priority_Inheritance_Enabled,
                          "PRIORITY_INHERITANCE_ENABLED");

   --
   -- Kernel semaphore support services
   --
   PROCEDURE Krn_Suspend (S : V_I_Sema.A_Semaphore);
   PRAGMA Interface (Ada, Krn_Suspend);
   PRAGMA Interface_Name (Krn_Suspend, "KRN_SUSPEND");
   FUNCTION Krn_Timed_Suspend
               (S : V_I_Sema.A_Semaphore; Timeout : Duration) RETURN Boolean;
   PRAGMA Interface (Ada, Krn_Timed_Suspend);
   PRAGMA Interface_Name (Krn_Timed_Suspend, "KRN_TIMED_SUSPEND");
   PROCEDURE Krn_Resume (S : V_I_Sema.A_Semaphore);
   PRAGMA Interface (Ada, Krn_Resume);
   PRAGMA Interface_Name (Krn_Resume, "KRN_RESUME");

   --
   -- Time operators
   --
   FUNCTION "+"  (Left : V_I_Types.Time_T; Right : V_I_Types.Time_T)
                RETURN V_I_Types.Time_T RENAMES V_I_Timeop."+";
   FUNCTION "-"  (Left : V_I_Types.Time_T; Right : V_I_Types.Time_T)
                RETURN Duration         RENAMES V_I_Timeop."-";
   FUNCTION "<=" (Left : V_I_Types.Time_T; Right : V_I_Types.Time_T)
                 RETURN Boolean         RENAMES V_I_Timeop."<=";

   --
   -- Support services from the archive semaphore routines
   --
   FUNCTION Prio_Inherit_Conditional_Enter
               (S : V_I_Sema.A_Semaphore) RETURN Boolean;
   PRAGMA Interface (Ada, Prio_Inherit_Conditional_Enter);
   PRAGMA Interface_Name (Prio_Inherit_Conditional_Enter,
                          "PRIO_INHERIT_CONDITIONAL_ENTER");
   PROCEDURE Prio_Inherit_Leave (S : V_I_Sema.A_Semaphore);
   PRAGMA Interface (Ada, Prio_Inherit_Leave);
   PRAGMA Interface_Name (Prio_Inherit_Leave, "PRIO_INHERIT_LEAVE");


   -- This routine is called to get a semaphore but will not wait if
   -- the semaphore is blocked.
   -- The success or failure of the enter is returned as a boolean.
   FUNCTION Conditional_Enter (S : V_I_Sema.A_Semaphore) RETURN Boolean IS
      Result : Boolean;
   BEGIN
      IF Priority_Inheritance_Enabled THEN
         RETURN Prio_Inherit_Conditional_Enter (S);
      END IF;

      V_Tas.Test_And_Set (S.Flag'Address, Result);
      RETURN Result;
   END Conditional_Enter;
   PRAGMA Inline_Only (Conditional_Enter);


   -- This routine is called to get a semaphore.  It blocks until it
   -- has it.
   PROCEDURE Enter (S : V_I_Sema.A_Semaphore) IS
   BEGIN
      LOOP
         EXIT WHEN Conditional_Enter (S);
         Krn_Suspend (S);
      END LOOP;
   END Enter;
   PRAGMA Inline_Only (Enter);


   -- This routine is called upon exiting a semaphore region in user code.
   PROCEDURE Leave (S : V_I_Sema.A_Semaphore) IS
   BEGIN
      IF Priority_Inheritance_Enabled THEN
         Prio_Inherit_Leave (S);
         RETURN;
      END IF;

      S.Flag := V_I_Types.Test_And_Set_False;
      IF V_I_Types."=" (S.Others_Waiting, V_I_Types.Test_And_Set_True) THEN
         Krn_Resume (S);
      END IF;
   END Leave;
   PRAGMA Inline_Only (Leave);

END V_Sema;