File: protected_example.adb

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procedure Protected_Example is 
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   type Priority is (High, Low); 
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   protected Trigger is 
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      entry Trigger_High; 
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      entry Trigger_Low; 
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      entry Queue (P : in Priority); 
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   private 
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      Current_Priority : Priority := Low;

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      Trigger : Boolean := False; 
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   end Trigger; 
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   protected body Trigger is 
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      entry Trigger_High when True is 
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      begin 
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         Current_Priority := High; 
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         Trigger:=True; 
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      end; 
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      entry Trigger_Low when True is 
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      begin 
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         Current_Priority := Low; 
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         Trigger:=True; 
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      end; 
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      entry Queue (P : in Priority) when Trigger is

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      begin 
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         if P /= Current_Priority then 
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            requeue QueueTo spec
To body;

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         end if; 
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         Trigger:=False; 
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      end; 
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   end Trigger; 
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   task type Priority_Task(P: Priority);

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   task body Priority_Task is 
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   begin 
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      Trigger.QueueTo spec
To body (P); 
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      if P = High then 
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         Trigger.Trigger_HighTo spec
To body;

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      end if; 
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   end Priority_TaskTo spec
To body; 
```
```
 
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   T1 : Priority_TaskTo spec
To body (Low);

   T2, T3, T4 : Priority_TaskTo spec
To body (High);

```
 
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begin 
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   delay 1.0; --seconds 
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   Trigger.Trigger_HighTo spec
To body; 
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   delay 1.0; --seconds 
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   Trigger.Trigger_LowTo spec
To body; 
```
```
end Protected_exampleTo spec
To body; 
```