31 lines
886 B
C
31 lines
886 B
C
#ifndef STACK_H
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#define STACK_H
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/* A stack is a special type of queue which uses the LIFO (last in, first out) principle.
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This means that with each new element all other elements are pushed deeper into the stack.
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The latest element is taken from the stack. */
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#include <stdlib.h>
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// Stack node for linked-list based stack. Data pointer is stored but not freed by stack operations.
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typedef struct StackNode
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{
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void *data;
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struct StackNode *next;
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} StackNode;
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// Pushes data as pointer onto the stack.
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StackNode *push(StackNode *stack, void *data);
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// Deletes the top element of the stack (latest added element) and releases its memory. (Pointer to data has to be
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// freed by caller.)
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StackNode *pop(StackNode *stack);
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// Returns the data of the top element.
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void *top(StackNode *stack);
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// Clears stack and releases all memory.
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void clearStack(StackNode *stack);
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#endif
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