/* SPDX-License-Identifier: LGPL-2.1+ */

#include <malloc.h>

#include <stdint.h>

#include <string.h>

#include "alloc-util.h"

#include "macro.h"

#include "memory-util.h"

void* memdup(const void *p, size_t l) {

        void *ret;

        assert(l == 0 || p);

        ret = malloc(l ?: 1);

        if (!ret)

                return NULL;

        memcpy(ret, p, l);

        return ret;

}

void* memdup_suffix0(const void *p, size_t l) {

        void *ret;

        assert(l == 0 || p);

        /* The same as memdup() but place a safety NUL byte after the allocated memory */

        if (_unlikely_(l == SIZE_MAX)) /* prevent overflow */

                return NULL;

        ret = malloc(l + 1);

        if (!ret)

                return NULL;

        *((uint8_t*) mempcpy(ret, p, l)) = 0;

        return ret;

}

void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size) {

        size_t a, newalloc;

        void *q;

        assert(p);

        assert(allocated);

        if (*allocated >= need)

                return *p;

        if (_unlikely_(need > SIZE_MAX/2)) /* Overflow check */

                return NULL;

        newalloc = need * 2;

        if (size_multiply_overflow(newalloc, size))

                return NULL;

        a = newalloc * size;

        if (a < 64) /* Allocate at least 64 bytes */

                a = 64;

        q = realloc(*p, a);

        if (!q)

                return NULL;

        if (size > 0) {

                size_t bn;

                /* Adjust for the 64 byte minimum */

                newalloc = a / size;

                bn = malloc_usable_size(q) / size;

                if (bn > newalloc) {

                        void *qq;

                        /* The actual size allocated is larger than what we asked for. Let's call realloc() again to

                         * take possession of the extra space. This should be cheap, since libc doesn't have to move

                         * the memory for this. */

                        qq = realloc(q, bn * size);

                        if (_likely_(qq)) {

                                *p = qq;

                                *allocated = bn;

                                return qq;

                        }

                }

        }

        *p = q;

        *allocated = newalloc;

        return q;

}

void* greedy_realloc0(void **p, size_t *allocated, size_t need, size_t size) {

        size_t prev;

        uint8_t *q;

        assert(p);

        assert(allocated);

        prev = *allocated;

        q = greedy_realloc(p, allocated, need, size);

        if (!q)

                return NULL;

        if (*allocated > prev)

                memzero(q + prev * size, (*allocated - prev) * size);

        return q;

}