/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include "lint.h"
#include "file64.h"
#include "mtlib.h"
#include <stdio.h>
#include <errno.h>
#include <thread.h>
#include <synch.h>
#include <unistd.h>
#include <limits.h>
#include <malloc.h>
#include <sys/types.h>
#include "stdiom.h"

#define LINESZ  128     /* initial guess for a NULL *lineptr */

ssize_t
getdelim(char **_RESTRICT_KYWD lineptr, size_t *_RESTRICT_KYWD n,
    int delimiter, FILE *_RESTRICT_KYWD iop)
{
        rmutex_t *lk;
        char *ptr;
        size_t size;
        int c;
        size_t cnt;

        if (lineptr == NULL || n == NULL ||
            delimiter < 0 || delimiter > UCHAR_MAX) {
                errno = EINVAL;
                return (-1);
        }

        if (*lineptr == NULL || *n < LINESZ) {  /* initial allocation */
                if ((*lineptr = realloc(*lineptr, LINESZ)) == NULL) {
                        errno = ENOMEM;
                        return (-1);
                }
                *n = LINESZ;
        }
        ptr = *lineptr;
        size = *n;
        cnt = 0;

        FLOCKFILE(lk, iop);

        _SET_ORIENTATION_BYTE(iop);

        do {
                c = (--iop->_cnt < 0) ? __filbuf(iop) : *iop->_ptr++;
                if (c == EOF)
                        break;
                *ptr++ = c;
                if (++cnt == size) {    /* must reallocate */
                        if ((ptr = realloc(*lineptr, 2 * size)) == NULL) {
                                FUNLOCKFILE(lk);
                                ptr = *lineptr + size - 1;
                                *ptr = '\0';
                                errno = ENOMEM;
                                return (-1);
                        }
                        *lineptr = ptr;
                        ptr += size;
                        *n = size = 2 * size;
                }
        } while (c != delimiter);

        *ptr = '\0';

        FUNLOCKFILE(lk);
        if (cnt > SSIZE_MAX) {
                errno = EOVERFLOW;
                return (-1);
        }
        return (cnt ? cnt : -1);
}

ssize_t
getline(char **_RESTRICT_KYWD lineptr, size_t *_RESTRICT_KYWD n,
    FILE *_RESTRICT_KYWD iop)
{
        return (getdelim(lineptr, n, '\n', iop));
}