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No commits in common. "b10d02a2a227f74978b3539dd4940f76ce60f10f" and "aa013fa349c8e4cdff5d30db1a79cb19fdc5a2d7" have entirely different histories.

5 changed files with 0 additions and 253 deletions

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@ -16,4 +16,3 @@ AlignConsecutiveDeclarations:
PadOperators: false
AlignConsecutiveMacros: true
AllowShortCaseLabelsOnASingleLine: true
SeparateDefinitionBlocks: Always

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@ -1,14 +0,0 @@
CC = gcc
CFLAGS = -Wall -O2
TARGET = main.elf
SRC = main.c freelist.c
#LDFLAGS =
$(TARGET): $(SRC)
@echo CC $@
@$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)
clean:
rm -f $(TARGET)

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@ -1,119 +0,0 @@
#include "freelist.h"
#include "stdbool.h"
#include "stddef.h"
#include <assert.h>
#include <bits/types/struct_itimerspec.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
/* Fiddle these around according to your need. */
#ifdef FREELIST_NOALIGN
#define ALIGN(x) (x)
#else // FREELIST_NOALIGN
/* Align to nearest multiple of sizeof(void*) */
static inline size_t align_up(size_t n) {
return (n + sizeof(void *) - 1) & ~(sizeof(void *) - 1);
}
#define ALIGN(x) (align_up(x))
#endif // FREELIST_NOALIGN
/* Initialize the FreeList */
int fl_init(FreeList *fl, uintptr_t start, uintptr_t end, size_t itemsize) {
size_t size = ALIGN(itemsize + sizeof(FreeListBlock));
if (!fl || end <= start)
return EXIT_FAILURE;
fl->start = start;
fl->end = end;
fl->size = size;
fl->allocated = 0;
FreeListBlock *block = (FreeListBlock *)start;
for (size_t i = 0; i < fl_capacity(fl); i++) {
block->next = (FreeListBlock *)((void *)block + size);
block->block_state = FL_FREE;
block = block->next;
}
block->next = NULL;
fl->free = (FreeListBlock *)start;
return EXIT_SUCCESS;
}
/* Allocate some memory from the FreeList */
void *fl_alloc(FreeList *fl) {
if (!fl->free || fl->free->block_state != FL_FREE)
return NULL;
FreeListBlock *m = fl->free;
m->block_state = FL_USED;
fl->free = fl->free->next;
fl->allocated++;
return ((void *)m) + sizeof(FreeListBlock);
}
/* Return some memory to the FreeList */
int fl_free(FreeList *fl, void *ptr) {
if (!fl_is_managed(fl, ptr)) {
return EXIT_FAILURE; /* We cant free memory we do not own */
}
FreeListBlock *block = (FreeListBlock *)((uintptr_t)ptr - sizeof(FreeListBlock));
if (block->block_state != FL_USED) {
return EXIT_FAILURE; /* Block must be used */
}
block->block_state = FL_FREE;
block->next = fl->free;
fl->free = block;
fl->allocated--;
return EXIT_SUCCESS;
}
/* Returns how many slots are occupied */
size_t fl_allocated(FreeList *fl) {
return fl->allocated;
}
/* Returns how many free slots are available (O(1)) */
size_t fl_available(FreeList *fl) {
return fl_capacity(fl) - fl->allocated;
}
/* Returns the total amount of items the freelist will hold */
size_t fl_capacity(FreeList *fl) {
return (fl->end - fl->start) / fl->size;
}
/* Check if a piece of memory is managed by the FreeList */
int fl_is_managed(FreeList *fl, void *ptr) {
return ((uintptr_t)ptr >= fl->start && (uintptr_t)ptr < fl->end);
}
/* Returns the ratio of metadata versus data as a scalar in range 0..1 */
float fl_utilization(FreeList *fl, size_t itemsize) {
return (float)itemsize / fl->size;
}
/* Walks the free pages/slots, returns total count (O(n), given no cycles) */
size_t fl_check(FreeList *fl) {
int avail = 0;
FreeListBlock *cursor = fl->free;
while (cursor->next != NULL) {
avail++;
assert(cursor->block_state == FL_FREE);
cursor = cursor->next;
}
return avail;
}

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@ -1,34 +0,0 @@
#ifndef FREELIST_H
#define FREELIST_H
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#define FL_FREE ((uint8_t)0x00)
#define FL_USED ((uint8_t)0x01)
typedef struct FreeListBlock {
struct FreeListBlock *next;
uint8_t block_state;
} FreeListBlock;
typedef struct {
uintptr_t start;
uintptr_t end;
FreeListBlock *free;
size_t size;
size_t allocated;
} FreeList;
int fl_init(FreeList *fl, uintptr_t start, uintptr_t end, size_t itemsize);
int fl_free(FreeList *fl, void *ptr);
int fl_is_managed(FreeList *fl, void *ptr);
void *fl_alloc(FreeList *fl);
size_t fl_check(FreeList *fl);
size_t fl_allocated(FreeList *fl);
size_t fl_available(FreeList *fl);
size_t fl_capacity(FreeList *fl);
float fl_utilization(FreeList *fl, size_t itemsize);
#endif // FREELIST_H

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@ -1,85 +0,0 @@
#include "freelist.h"
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct {
int x, y, z;
} Vec3;
Vec3 vec3_new(int a, int b, int c) {
return (Vec3){a, b, c};
}
// Print function
void printvec(const Vec3 *v) {
printf("Vec3: (%d, %d, %d)\n", v->x, v->y, v->z);
}
int main() {
FreeList fl;
char *mem = malloc(4096);
fl_init(&fl, (uintptr_t)mem, (uintptr_t)mem + 4096, sizeof(Vec3));
size_t cap = fl_capacity(&fl);
assert(fl_available(&fl) == cap);
printf("Space utilization: %.2f%%\n", 100.0 * fl_utilization(&fl, sizeof(Vec3)));
Vec3 *a = fl_alloc(&fl);
Vec3 *b = fl_alloc(&fl);
Vec3 *c = fl_alloc(&fl);
memset(a, 0x23, sizeof(Vec3));
memset(b, 0x24, sizeof(Vec3));
memset(c, 0x25, sizeof(Vec3));
*a = vec3_new(12, 13, 435);
*b = vec3_new(192, 199, 435);
*c = vec3_new(432, 11, 435);
printvec(a);
printvec(b);
printvec(c);
assert(fl_check(&fl) == cap - 3);
assert(fl_capacity(&fl) == fl_available(&fl) + 3);
printf("Available: %zu of %zu\n", fl_available(&fl), fl_capacity(&fl));
assert(fl_free(&fl, a) == EXIT_SUCCESS);
assert(fl_free(&fl, b) == EXIT_SUCCESS);
assert(fl_free(&fl, c) == EXIT_SUCCESS);
assert(fl_free(&fl, a) == EXIT_FAILURE); // Double free
printf("Available: %zu of %zu\n", fl_available(&fl), fl_capacity(&fl));
assert(fl_check(&fl) == fl_capacity(&fl) - fl_allocated(&fl));
assert(fl_allocated(&fl) == 0);
/* All memory is free here */
uintptr_t *ptr_buf = malloc(sizeof(uintptr_t) * fl_capacity(&fl));
/* Fill it up */
for (int i = 0; i < fl_capacity(&fl); i++) {
ptr_buf[i] = (uintptr_t)fl_alloc(&fl);
}
assert(0 == fl_available(&fl));
assert(fl_allocated(&fl) == fl_capacity(&fl));
assert(fl_check(&fl) == 0);
/* Return it all */
for (int i = 0; i < fl_capacity(&fl); i++) {
fl_free(&fl, (void *)ptr_buf[i]);
}
assert(cap == fl_available(&fl));
assert(fl_allocated(&fl) == 0);
assert(fl_check(&fl) == cap);
printf("All tests passed!\n");
return 0;
}