string.h

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/* SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright(c) 2022 Intel Corporation. All rights reserved.
 */
 
#ifndef __ZEPHYR_RTOS_STRING_H__
#define __ZEPHYR_RTOS_STRING_H__
 
/* Zephyr uses a C library so lets use it */
#include <string.h>
#include <stdint.h>
#include <stddef.h>
#include <errno.h>
 
void *__vec_memcpy(void *dst, const void *src, size_t len);
void *__vec_memset(void *dest, int data, size_t src_size);
 
#ifdef __cplusplus
extern "C" {
#endif
/* missing from zephyr - TODO: convert to memset() */
#define bzero(ptr, size) \
    memset(ptr, 0, size)
 
/* TODO: need converted to C library calling conventions */
static inline int rstrlen(const char *s)
{
    return strlen(s);
}
 
/* TODO: need converted to C library calling conventions */
static inline int rstrcmp(const char *s1, const char *s2)
{
    return strcmp(s1, s2);
}
 
/* C library does not have the "_s" versions used by Windows */
static inline int memcpy_s(void *dest, size_t dest_size,
               const void *src, size_t count)
{
    if (!dest || !src)
        return -EINVAL;
 
    if (count > dest_size)
        return -EINVAL;
 
    uintptr_t dest_addr = (uintptr_t)dest;
    uintptr_t src_addr = (uintptr_t)src;
 
    /* Check for overflow in pointer arithmetic */
    if ((dest_addr + dest_size < dest_addr) || (src_addr + count < src_addr))
        return -EINVAL;
 
    /* Check for overlap without causing overflow */
    if ((dest_addr >= src_addr && dest_addr < src_addr + count) ||
        (src_addr >= dest_addr && src_addr < dest_addr + dest_size))
        return -EINVAL;
 
    memcpy(dest, src, count);
 
    return 0;
}
 
static inline int memset_s(void *dest, size_t dest_size, int data, size_t count)
{
    if (!dest)
        return -EINVAL;
 
    if (count > dest_size)
        return -EINVAL;
 
    memset(dest, data, count);
    /*
     * Prevent compiler from optimizing away the memset.
     * Memory barrier prevents dead store elimination.
     */
#if defined(CONFIG_XTENSA)
    __asm__ __volatile__("memw" ::: "memory");
#endif
 
    return 0;
}
 
#ifdef __cplusplus
} /* extern "C" */
#endif
 
#endif /* __ZEPHYR_RTOS_STRING_H__ */