54 lines
1.5 KiB
Plaintext
54 lines
1.5 KiB
Plaintext
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DEFINITION MODULE Storage;
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(*
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Standard dynamic storage management
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Derived from the Lilith Modula-2 system developed by the
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group of Prof. N. Wirth at ETH Zurich, Switzerland.
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Storage management for dynamic variables. Calls to the
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Modula-2 standard procedures NEW and DISPOSE are translated
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into calls to ALLOCATE and DEALLOCATE. The standard way to
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provide these two procedures is to import them from this
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module 'Storage'.
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*)
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FROM SYSTEM IMPORT ADDRESS;
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EXPORT QUALIFIED
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ALLOCATE, DEALLOCATE, Available, InstallHeap, RemoveHeap;
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PROCEDURE ALLOCATE (VAR a: ADDRESS; size: CARDINAL);
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(*- Allocate some dynamic storage.
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in: size number of bytes to allocate,
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out: a ADDRESS of allocated storage.
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The actual number of bytes allocated may be slightly greater
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than 'size', due to administrative overhead.
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If not enough space is available, the calling program is
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terminated with the status 'heapovf'.
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*)
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PROCEDURE DEALLOCATE (VAR a: ADDRESS; size: CARDINAL);
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(*- Release some dynamic storage.
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in: a ADDRESS of the area to release,
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size number of bytes to be released,
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out: a set to NIL.
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*)
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PROCEDURE Available (size: CARDINAL) : BOOLEAN;
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(*- Test whether some number of bytes could be allocated.
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in: size number of bytes
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out: TRUE if ALLOCATE(p,size) would succeed.
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*)
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PROCEDURE InstallHeap;
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(*- Used by the loader -*)
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PROCEDURE RemoveHeap;
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(*- Used by the loader -*)
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END Storage.
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