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/***
This file is part of LockPassword
Copyright (C) 2020-2025 Aleksandr D. Goncharov (Joursoir) <chat@joursoir.net>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
***/
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include "xstd.h"
char *xstrcat(const char *first, ...)
{
va_list args;
const char *s;
size_t total_len = 0;
size_t len;
// 1. Calculate the total length required
if (first != NULL) {
total_len += strlen(first);
}
va_start(args, first);
while ((s = va_arg(args, const char *)) != NULL) {
total_len += strlen(s);
}
va_end(args);
// 2. Allocate memory for the concatenated string
char *result = malloc(total_len + 1);
if (result == NULL) {
return NULL;
}
char *ptr = result;
// 3. Copy the first string and then the rest of the strings
if (first != NULL) {
len = strlen(first);
memcpy(ptr, first, len);
ptr += len;
}
va_start(args, first);
while ((s = va_arg(args, const char *)) != NULL) {
len = strlen(s);
memcpy(ptr, s, len);
ptr += len;
}
va_end(args);
*ptr = '\0';
return result;
}
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