copy.c

/*******************************************************************************
 * File: copy.c
 * Created: 2022-08-03
 *
 * Authors:
 *   Tyler Matijevich
 *
 * License:
 *   This file copy.c is part of the IecString project
 *   released under the MIT license agreement.
 ******************************************************************************/

#include "main.h"

/* Copy source to destination up to size of destination or source length */
int32_t IecStringCopy(char *destination, uint32_t size, char *source)
{
    /* Gaurd null pointers */
    if (!destination || !source)
        return IECSTRING_ERROR_NULL;

    /* Check for zero size */
    if (!size)
        return IECSTRING_ERROR_SIZE_ZERO;

    /* Check if source overlaps destination size */
    if (destination <= source && source < destination + size)
        return IECSTRING_ERROR_OVERLAP;

    /* Check if destination overlaps source length */
    size_t source_length = strlen(source);
    if (source <= destination && destination <= source + source_length)
        return IECSTRING_ERROR_OVERLAP;

    /* Copy the safe and optimal number of characters */
    size_t min_char_count = MIN(size - 1, source_length);
    strncpy(destination, source, min_char_count);

    /* Add null terminator */
    destination[min_char_count] = '\0';

    /* Truncated if source length exceeds size */
    return IECSTRING_WARNING_TRUNCATE * (source_length > size - 1);
}