41 lines
1.2 KiB
Markdown
41 lines
1.2 KiB
Markdown
# A Buddy Allocator
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This is a general purpose allocator designed for memory-constrained environments. It uses the Buddy System allocation scheme. Only allocations with a size that is a power of 2 are supported. Any size other that's not a power of 2 will be rounded up.
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Here's an example:
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```c
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#include <stdio.h>
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#include <string.h>
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#include "buddy.h"
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int main(void)
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{
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#define NUM_PAGES 16
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// This is the memory we will allocate from
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char memory[NUM_PAGES * BUDDY_ALLOC_MAX_BLOCK_SIZE];
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struct page_info info[NUM_PAGES]; // This is required to keep track of allocation state
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struct buddy_alloc alloc = buddy_startup(memory, sizeof(memory), info, NUM_PAGES);
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// Allocate some memory (NULL is returned on failure)
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// If the memory pool passed to the allocator was properly aligned,
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// you can count to allocate any and all bytes of that pool.
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char *str1 = buddy_malloc(&alloc, 32);
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char *str2 = buddy_malloc(&alloc, 32);
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strncpy(str1, "Hello", 32);
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strncpy(str2, "world", 32);
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printf("%s, %s!\n", str1, str2);
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buddy_free(&alloc, 32, str1);
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buddy_free(&alloc, 32, str2);
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buddy_free(&alloc, 32, str2); // Double frees are caught!
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buddy_cleanup(&alloc);
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return 0;
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}
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```
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