root/usr.bin/tmux/xmalloc.c
/* $OpenBSD: xmalloc.c,v 1.15 2026/07/12 20:16:20 nicm Exp $ */

/*
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 * Versions of malloc and friends that check their results, and never return
 * failure (they call fatalx if they encounter an error).
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 */

#include <errno.h>
#include <limits.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "tmux.h"

void *
xmalloc(size_t size)
{
        void *ptr;

        if (size == 0)
                fatalx("xmalloc: zero size");
        ptr = malloc(size);
        if (ptr == NULL)
                fatal("xmalloc: allocating %zu bytes", size);
        return ptr;
}

void *
xcalloc(size_t nmemb, size_t size)
{
        void *ptr;

        if (size == 0 || nmemb == 0)
                fatalx("xcalloc: zero size");
        if (SIZE_MAX / nmemb < size)
                fatalx("xcalloc: nmemb * size > SIZE_MAX");
        ptr = calloc(nmemb, size);
        if (ptr == NULL)
                fatal("xcalloc: allocating %zu bytes", size * nmemb);
        return ptr;
}

void *
xrealloc(void *ptr, size_t size)
{
        return xreallocarray(ptr, 1, size);
}

void *
xreallocarray(void *ptr, size_t nmemb, size_t size)
{
        void *new_ptr;

        if (nmemb == 0 || size == 0)
                fatalx("xreallocarray: zero size");
        new_ptr = reallocarray(ptr, nmemb, size);
        if (new_ptr == NULL)
                fatal("xreallocarray: allocating %zu bytes", size * nmemb);
        return new_ptr;
}

void *
xrecallocarray(void *ptr, size_t oldnmemb, size_t nmemb, size_t size)
{
        void *new_ptr;

        if (nmemb == 0 || size == 0)
                fatalx("xrecallocarray: zero size");
        new_ptr = recallocarray(ptr, oldnmemb, nmemb, size);
        if (new_ptr == NULL)
                fatal("xrecallocarray: allocating %zu bytes", size * nmemb);
        return new_ptr;
}

char *
xstrdup(const char *str)
{
        char *cp;

        if ((cp = strdup(str)) == NULL)
                fatal("xstrdup");
        return cp;
}

char *
xstrndup(const char *str, size_t maxlen)
{
        char *cp;

        if ((cp = strndup(str, maxlen)) == NULL)
                fatal("xstrndup");
        return cp;
}

char *
xmemdup(const void *ptr, size_t len)
{
        char *cp;

        cp = xmalloc(len + 1);
        if (len != 0)
                memcpy(cp, ptr, len);
        cp[len] = '\0';
        return cp;
}

int
xasprintf(char **ret, const char *fmt, ...)
{
        va_list ap;
        int i;

        va_start(ap, fmt);
        i = xvasprintf(ret, fmt, ap);
        va_end(ap);
        return i;
}

int
xvasprintf(char **ret, const char *fmt, va_list ap)
{
        int i;

        i = vasprintf(ret, fmt, ap);
        if (i == -1 || *ret == NULL)
                fatal("xvasprintf");
        return i;
}

int
xsnprintf(char *str, size_t len, const char *fmt, ...)
{
        va_list ap;
        int i;

        va_start(ap, fmt);
        i = xvsnprintf(str, len, fmt, ap);
        va_end(ap);
        return i;
}

int
xvsnprintf(char *str, size_t len, const char *fmt, va_list ap)
{
        int i;

        if (len > INT_MAX)
                fatalx("xsnprintf: len > INT_MAX");
        i = vsnprintf(str, len, fmt, ap);
        if (i < 0 || i >= (int)len)
                fatalx("xsnprintf: overflow");
        return i;
}