42 lines
1.2 KiB
Modula-2
42 lines
1.2 KiB
Modula-2
DEFINITION MODULE Storage;
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(*
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Module: Dynamic storage allocation
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From: "Programming in Modula-2", 3rd, corrected edition, by N. Wirth
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Version: $Header$
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*)
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(*
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Wirth's 3rd edition certainly is confusing: mostly it uses Allocate, but
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the module at the end of the book defines ALLOCATE. To avoid problems,
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I included them both.
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*)
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FROM SYSTEM IMPORT ADDRESS;
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PROCEDURE ALLOCATE(VAR a : ADDRESS; size : CARDINAL);
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(* Allocate an area of the given size and return the address
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in "a". If no space is available, the calling program is
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killed.
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*)
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PROCEDURE Allocate(VAR a : ADDRESS; size : CARDINAL);
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(* Identical to ALLOCATE *)
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PROCEDURE DEALLOCATE(VAR a : ADDRESS; size : CARDINAL);
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(* Free the area at address "a" with the given size. The area
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must have been allocated by "ALLOCATE", with the same size.
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*)
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PROCEDURE Deallocate(VAR a : ADDRESS; size : CARDINAL);
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(* Identical to DEALLOCATE *)
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PROCEDURE Available(size : CARDINAL) : BOOLEAN;
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(* Return TRUE if a contiguous area with the given size could be
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allocated.
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Notice that this only indicates if an ALLOCATE of this size
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would succeed, and that it gives no indication of the total
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available memory.
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*)
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END Storage.
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