55 lines
1.5 KiB
C
55 lines
1.5 KiB
C
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#ifndef INCLUDED_C_MERGESORT_H
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#define INCLUDED_C_MERGESORT_H
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#ifndef INCLUDED_C_TYPES_H
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#include <c_Types.h>
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#endif /*INCLUDED_C_TYPES_H*/
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#ifndef INCLUDED_C_MEMORY_H
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#include <c_Memory.h>
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#endif /*INCLUDED_C_MEMORY_H*/
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/* ------------------------------------------------------------------------------------------------------------------ */
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/* */
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void c_MergeSortSub(char* arr, c_size_t left, c_size_t right, c_size_t size, char* aux,
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int (*compar)(const void*, const void*));
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/**
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* Top-Level Custom Framework Entry Point for Top-Down Merge Sort.
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* Time Complexity: O(n log n) | Space Complexity: O(n) | Stable: Yes
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*/
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C_STATIC_FORCE_INLINE
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void c_MergeSort(void* base, c_size_t num, c_size_t size,
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int (*compar)(const void*, const void*)) {
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if (base == NULL || num < 2 || size == 0) return;
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char* arr = (char*)base;
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c_size_t total_bytes = num * size;
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// Optimization: Fallback to stack buffer allocation if overall payload fits locally
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#define MERGE_STACK_LIMIT 512
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char stack_buf[MERGE_STACK_LIMIT];
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char* aux = NULL;
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if (total_bytes <= MERGE_STACK_LIMIT) {
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aux = stack_buf;
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} else {
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aux = (char*)C_ALLOC(total_bytes);
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if (aux == NULL) return; // Allocation safeguard
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}
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// Execute recursive divide-and-conquer strategy
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c_MergeSortSub(arr, 0, num - 1, size, aux, compar);
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if (total_bytes > MERGE_STACK_LIMIT) {
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C_FREE(aux);
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}
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#undef MERGE_STACK_LIMIT
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}
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#endif /*INCLUDED_C_MERGESORT_H*/
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