#include "cx/mempool.h"
#include "cx/utils.h"
#include <string.h>
struct cx_mempool_memory_s {
cx_destructor_func destructor;
char c[];
};
static void *cx_mempool_malloc(
void *p,
size_t n
) {
struct cx_mempool_s *pool = p;
if (pool->size >= pool->capacity) {
size_t newcap = pool->capacity - (pool->capacity %
16) +
16;
struct cx_mempool_memory_s **newdata = realloc(pool->data, newcap*
sizeof(
struct cx_mempool_memory_s*));
if (newdata ==
NULL) {
return NULL;
}
pool->data = newdata;
pool->capacity = newcap;
}
struct cx_mempool_memory_s *mem = malloc(
sizeof(cx_destructor_func) + n);
if (mem ==
NULL) {
return NULL;
}
mem->destructor = pool->auto_destr;
pool->data[pool->size] = mem;
pool->size++;
return mem->c;
}
static void *cx_mempool_calloc(
void *p,
size_t nelem,
size_t elsize
) {
size_t msz;
if (cx_szmul(nelem, elsize, &msz)) {
return NULL;
}
void *ptr = cx_mempool_malloc(p, msz);
if (ptr ==
NULL) {
return NULL;
}
memset(ptr,
0, nelem * elsize);
return ptr;
}
static void *cx_mempool_realloc(
void *p,
void *ptr,
size_t n
) {
struct cx_mempool_s *pool = p;
struct cx_mempool_memory_s *mem, *newm;
mem = (
struct cx_mempool_memory_s*)(((
char *) ptr) -
sizeof(cx_destructor_func));
newm = realloc(mem, n +
sizeof(cx_destructor_func));
if (newm ==
NULL) {
return NULL;
}
if (mem != newm) {
cx_for_n(i, pool->size) {
if (pool->data[i] == mem) {
pool->data[i] = newm;
return ((
char*)newm) +
sizeof(cx_destructor_func);
}
}
abort();
}
else {
return ptr;
}
}
static void cx_mempool_free(
void *p,
void *ptr
) {
if (!ptr)
return;
struct cx_mempool_s *pool = p;
struct cx_mempool_memory_s *mem = (
struct cx_mempool_memory_s *)
((
char *) ptr -
sizeof(cx_destructor_func));
cx_for_n(i, pool->size) {
if (mem == pool->data[i]) {
if (mem->destructor) {
mem->destructor(mem->c);
}
free(mem);
size_t last_index = pool->size -
1;
if (i != last_index) {
pool->data[i] = pool->data[last_index];
pool->data[last_index] =
NULL;
}
pool->size--;
return;
}
}
abort();
}
void cxMempoolDestroy(CxMempool *pool) {
struct cx_mempool_memory_s *mem;
cx_for_n(i, pool->size) {
mem = pool->data[i];
if (mem->destructor) {
mem->destructor(mem->c);
}
free(mem);
}
free(pool->data);
free((
void*) pool->allocator);
free(pool);
}
void cxMempoolSetDestructor(
void *ptr,
cx_destructor_func func
) {
*(cx_destructor_func *) ((
char *) ptr -
sizeof(cx_destructor_func)) = func;
}
struct cx_mempool_foreign_mem_s {
cx_destructor_func destr;
void* mem;
};
static void cx_mempool_destr_foreign_mem(
void* ptr) {
struct cx_mempool_foreign_mem_s *fm = ptr;
fm->destr(fm->mem);
}
int cxMempoolRegister(
CxMempool *pool,
void *memory,
cx_destructor_func destr
) {
struct cx_mempool_foreign_mem_s *fm = cx_mempool_malloc(
pool,
sizeof(
struct cx_mempool_foreign_mem_s)
);
if (fm ==
NULL)
return 1;
fm->mem = memory;
fm->destr = destr;
*(cx_destructor_func *) ((
char *) fm -
sizeof(cx_destructor_func)) = cx_mempool_destr_foreign_mem;
return 0;
}
static cx_allocator_class cx_mempool_allocator_class = {
cx_mempool_malloc,
cx_mempool_realloc,
cx_mempool_calloc,
cx_mempool_free
};
CxMempool *cxMempoolCreate(
size_t capacity,
cx_destructor_func destr
) {
size_t poolsize;
if (cx_szmul(capacity,
sizeof(
struct cx_mempool_memory_s*), &poolsize)) {
return NULL;
}
struct cx_mempool_s *pool =
malloc(
sizeof(
struct cx_mempool_s));
if (pool ==
NULL) {
return NULL;
}
CxAllocator *provided_allocator = malloc(
sizeof(CxAllocator));
if (provided_allocator ==
NULL) {
free(pool);
return NULL;
}
provided_allocator->cl = &cx_mempool_allocator_class;
provided_allocator->data = pool;
pool->allocator = provided_allocator;
pool->data = malloc(poolsize);
if (pool->data ==
NULL) {
free(provided_allocator);
free(pool);
return NULL;
}
pool->size =
0;
pool->capacity = capacity;
pool->auto_destr = destr;
return (CxMempool *) pool;
}