120 lines
4.0 KiB
C
120 lines
4.0 KiB
C
#ifndef MEMORY_MANAGER_H
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#define MEMORY_MANAGER_H
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/* memory_manager.h
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*
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* External (public) declarations for a memory manager in c.
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*
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* Clients begin by initializing the memory manager. They can
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* then allocate and free blocks of memory. The memory manager
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* keeps track of allocated and free blocks to maintain efficient
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* use of memory.
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*
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*/
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/* Structures */
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/* No "public" structure, the user of the memory manager
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* should have no knowledge of the structures used for managing
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* allocated and free blocks
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*/
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/* Memory Manager Methods */
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/* mmInit()
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* Initialize the memory manager to "manage" the given location
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* in memory with the specified size.
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* Parameters: start - the start of the memory to manage
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* size - the size of the memory to manage
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* Returns: void
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*/
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void mmInit(void* start, int size);
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/* mmDestroy()
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* Cleans up any storage used by the memory manager
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* After a call to mmDestroy:
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* all allocated spaces become invalid
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* future allocation attempts fail
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* future frees result in segmentation faults
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* NOTE: after a call to mmDestroy a call to mmInit
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* reinitializes the memory manager to allow allocations
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* and frees
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* Parameters: None
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* Returns: void
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*/
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void mmDestroy();
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/* mymalloc_ff()
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* Requests a block of memory be allocated using
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* first fit placement algorithm
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* The memory manager must be initialized (mmInit)
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* for this call to succeed
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* Parameters: nbytes - the number of bytes in the requested memory
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* Returns: void* - a pointer to the start of the allocated space
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*/
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void* mymalloc_ff(int nbytes);
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/* mymalloc_wf()
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* Requests a block of memory be allocated using
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* worst fit placement algorithm
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* The memory manager must be initialized (mmInit)
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* for this call to succeed
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* Parameters: nbytes - the number of bytes in the requested memory
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* Returns: void* - a pointer to the start of the allocated space
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*/
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void* mymalloc_wf(int nbytes);
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/* mymalloc_bf()
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* Requests a block of memory be allocated using
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* best fit placement algorithm
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* The memory manager must be initialized (mmInit)
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* for this call to succeed
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* Parameters: nbytes - the number of bytes in the requested memory
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* Returns: void* - a pointer to the start of the allocated space
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*/
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void* mymalloc_bf(int nbytes);
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/* myfree()
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* Requests a block of memory be freed and the storage made
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* available for future allocations
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* The memory manager must be initialized (mmInit)
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* for this call to succeed
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* Parameters: ptr - a pointer to the start of the space to be freed
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* Returns: void
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* Signals a SIGSEGV if a free is not valid
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* - memory manager is not initialized
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* - memory manager has been destroyed
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* - ptr is not allocated (e.g. double free)
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*/
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void myfree(void* ptr);
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/* get_allocated_space()
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* Retrieve the current amount of space allocated by the memory manager (in bytes)
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* Parameters: None
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* Returns: int - the current number of allocated bytes
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*/
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int get_allocated_space();
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/* get_remaining_space()
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* Retrieve the current amount of available space in the memory manager (in bytes)
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* (e.g. sum of all free blocks)
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* Parameters: None
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* Returns: int - the current number of free bytes
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*/
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int get_remaining_space();
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/* get_fragment_count()
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* Retrieve the current amount of free blocks (i.e. the count of all the block, not the size)
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* Parameters: None
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* Returns: int - the current number of free blocks
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*/
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int get_fragment_count();
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/* get_mymalloc_count()
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* Retrieve the number of successful malloc calls (for all placement types)
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* Parameters: None
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* Returns: int - the total number of successful mallocs
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*/
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int get_mymalloc_count();
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#endif
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