/**

 * @file compat.c

 * @author Michal Vasko <mvasko@cesnet.cz>

 * @brief compatibility functions

 *

 * Copyright (c) 2020 CESNET, z.s.p.o.

 *

 * This source code is licensed under BSD 3-Clause License (the "License").

 * You may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     https://opensource.org/licenses/BSD-3-Clause

 */

#include "compat.h"

#define _POSIX_C_SOURCE 200809L /* fdopen, _POSIX_PATH_MAX, strdup */

#define _ISOC99_SOURCE /* vsnprintf */

#include <errno.h>

#include <limits.h>

#include <stdarg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#ifndef HAVE_VDPRINTF

int

vdprintf(int fd, const char *format, va_list ap)

{

    FILE *stream;

    int count = 0;

    stream = fdopen(dup(fd), "a+");

    if (stream) {

        count = vfprintf(stream, format, ap);

        fclose(stream);

    }

    return count;

}

#endif

#ifndef HAVE_ASPRINTF

int

asprintf(char **strp, const char *fmt, ...)

{

    int ret;

    va_list ap;

    va_start(ap, fmt);

    ret = vasprintf(strp, fmt, ap);

    va_end(ap);

    return ret;

}

#endif

#ifndef HAVE_VASPRINTF

int

vasprintf(char **strp, const char *fmt, va_list ap)

{

    va_list ap2;

    va_copy(ap2, ap);

    int l = vsnprintf(0, 0, fmt, ap2);

    va_end(ap2);

    if ((l < 0) || !(*strp = malloc(l + 1U))) {

        return -1;

    }

    return vsnprintf(*strp, l + 1U, fmt, ap);

}

#endif

#ifndef HAVE_STRNDUP

char *

strndup(const char *s, size_t n)

{

    char *buf;

    size_t len = 0;

    /* strnlen */

    for ( ; (len < n) && (s[len] != '\0'); ++len) {}

    if (!(buf = malloc(len + 1U))) {

        return NULL;

    }

    memcpy(buf, s, len);

    buf[len] = '\0';

    return buf;

}

#endif

#ifndef HAVE_STRNSTR

char *

strnstr(const char *s, const char *find, size_t slen)

{

    char c, sc;

    size_t len;

    if ((c = *find++) != '\0') {

        len = strlen(find);

        do {

            do {

                if ((slen-- < 1) || ((sc = *s++) == '\0')) {

                    return NULL;

                }

            } while (sc != c);

            if (len > slen) {

                return NULL;

            }

        } while (strncmp(s, find, len));

        s--;

    }

    return (char *)s;

}

#endif

#ifndef HAVE_GETLINE

ssize_t

getline(char **lineptr, size_t *n, FILE *stream)

{

    static char line[256];

    char *ptr;

    ssize_t len;

    if (!lineptr || !n) {

        errno = EINVAL;

        return -1;

    }

    if (ferror(stream) || feof(stream)) {

        return -1;

    }

    if (!fgets(line, 256, stream)) {

        return -1;

    }

    ptr = strchr(line, '\n');

    if (ptr) {

        *ptr = '\0';

    }

    len = strlen(line);

    if (len + 1 < 256) {

        ptr = realloc(*lineptr, 256);

        if (!ptr) {

            return -1;

        }

        *lineptr = ptr;

        *n = 256;

    }

    strcpy(*lineptr, line);

    return len;

}

#endif

#ifndef HAVE_GET_CURRENT_DIR_NAME

char *

get_current_dir_name(void)

{

    char tmp[_POSIX_PATH_MAX];

    char *retval = NULL;

    if (getcwd(tmp, sizeof(tmp))) {

        retval = strdup(tmp);

        if (!retval) {

            errno = ENOMEM;

        }

    }

    return retval;

}

#endif