/***************************************************************************
 * sys_wrap.c -- Error-checked wrappers around common functions.           *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
 *                                                                         *
 * The Nmap Security Scanner is (C) 1996-2022 Nmap Software LLC ("The Nmap *
 * Project"). Nmap is also a registered trademark of the Nmap Project.     *
 *                                                                         *
 * This program is distributed under the terms of the Nmap Public Source   *
 * License (NPSL). The exact license text applying to a particular Nmap    *
 * release or source code control revision is contained in the LICENSE     *
 * file distributed with that version of Nmap or source code control       *
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 * header summarizes some key points from the Nmap license, but is no      *
 * substitute for the actual license text.                                 *
 *                                                                         *
 * Nmap is generally free for end users to download and use themselves,    *
 * including commercial use. It is available from https://nmap.org.        *
 *                                                                         *
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 * stating terms other than these (such as an Nmap OEM license), you may   *
 * choose to use and redistribute Nmap under those terms instead.          *
 *                                                                         *
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 * (https://npcap.com) for packet capture and transmission. It is under    *
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 * redistributed without special permission (such as an Nmap OEM           *
 * license).                                                               *
 *                                                                         *
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 * right to know exactly what a program is going to do before they run it. *
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 *                                                                         *
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 *                                                                         *
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 *                                                                         *
 ***************************************************************************/

/* $Id$ */

#include <limits.h>

#include "sys_wrap.h"
#include "util.h"

void *Calloc(size_t nmemb, size_t size)
{
    void *ret;

    /* older libcs don't check for int overflow */
    smul(nmemb, size);

    ret = calloc(nmemb, size);
    if (ret == NULL)
        die("calloc");

    return ret;
}

int Close(int fd)
{
    if (close(fd) < 0)
        die("close");

    return 0;
}

int Connect(int sockfd, const struct sockaddr *serv_addr, socklen_t addrlen)
{
    if (connect(sockfd, serv_addr, addrlen) < 0)
        die("connect");

    return 0;
}

int Dup2(int oldfd, int newfd)
{
    int ret;

    ret = dup2(oldfd, newfd);
    if (ret < 0)
        die("dup2");

    return ret;
}

int Listen(int s, int backlog)
{
    if (listen(s, backlog) < 0)
        die("listen");

    return 0;
}

int Open(const char *pathname, int flags, mode_t mode)
{
    int ret;

    ret = open(pathname, flags, mode);
    if (ret < 0)
        die("open");

    return ret;
}

ssize_t Read(int fd, void *buf, size_t count)
{
    ssize_t ret;

    ret = read(fd, buf, count);
    if (ret < 0)
        die("read");

    return ret;
}

int Setsockopt(int s, int level, int optname, const void *optval,
                    socklen_t optlen)
{
    int ret;

    ret = setsockopt(s, level, optname, (const char *) optval, optlen);
    if (ret < 0)
        die("setsockopt");

    return ret;
}

sighandler_t Signal(int signum, sighandler_t handler)
{
    sighandler_t ret;

    ret = signal(signum, handler);
    if (ret == SIG_ERR)
        die("signal");

    return ret;
}


int Socket(int domain, int type, int protocol)
{
    int ret;

    ret = socket(domain, type, protocol);
    if (ret < 0)
        die("socket");

    return ret;
}

char *Strdup(const char *s)
{
    char *ret;

    ret = strdup(s);
    if (ret == NULL)
        die("strdup");

    return ret;
}

ssize_t Write(int fd, const void *buf, size_t count)
{
    ssize_t ret = write(fd, buf, count);

    if (ret < 0)         /* we don't bail if < count bytes written */
        die("write");

    return ret;
}