#include "precompile.h"
#include "memutil.h"
#include "array.h"
#include "shm_array.h"
#include "shm_mem.h"

#define DEFAULT_NUM	15

TOOLKIT_API array_header_t *shm_array_make(int nelts, int elt_size)
{
	array_header_t *arr = shm_malloc(sizeof(array_header_t));
	if (nelts <= 0)
		nelts = DEFAULT_NUM;
	arr->elts = shm_malloc(elt_size * nelts);
	arr->elt_size = elt_size;
	arr->nelts = 0;
	arr->nalloc = nelts;
	return arr;
}

TOOLKIT_API void shm_array_free(array_header_t *arr)
{
	shm_free(arr->elts);
	shm_free(arr);
}

TOOLKIT_API void shm_array_free2(array_header_t *arr)
{
	int i;
	for (i = 0; i < arr->nelts; ++i) {
		shm_free(ARRAY_IDX(arr, i, void*));
	}
	shm_free(arr->elts);
	shm_free(arr);
}

TOOLKIT_API void *shm_array_push(array_header_t *arr)
{
	shm_array_check_expand(&arr->elts, arr->elt_size, arr->nelts, &arr->nalloc);
	return arr->elts + (arr->elt_size * (arr->nelts++));
}

TOOLKIT_API void shm_array_cat(array_header_t *dst, const array_header_t *src)
{
	int elt_size = dst->elt_size;
	if (dst->nelts + src->nelts > dst->nalloc) {
		int new_size = (dst->nalloc <= 0) ? 1 : dst->nalloc * 2;
		char *new_data;

		while (dst->nelts + src->nelts > new_size) {
			new_size *= 2;
		}

		new_data = shm_malloc(elt_size * new_size);
		memcpy(new_data, dst->elts, dst->nalloc * elt_size);
		shm_free(dst->elts);
		dst->elts = new_data;
		dst->nalloc = new_size;
	}

	memcpy(dst->elts + dst->nelts * elt_size, src->elts,
		elt_size * src->nelts);
	dst->nelts += src->nelts;
}

TOOLKIT_API array_header_t * shm_array_copy(const array_header_t *arr)
{
	array_header_t *res = shm_array_make(arr->nelts, arr->elt_size);
	memcpy(res->elts, arr->elts, arr->elt_size * arr->nelts);
	res->nelts = arr->nelts;
	memset(res->elts + res->elt_size * res->nelts, 0,
		res->elt_size * (res->nalloc - res->nelts));
	return res;
}