/* getdelim.c --- Implementation of replacement getdelim function.

   Copyright (C) 1994, 1996-1998, 2001, 2003, 2005-2020 Free Software

   Foundation, Inc.

   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, 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/>.  */

/* Ported from glibc by Simon Josefsson. */

/* Don't use __attribute__ __nonnull__ in this compilation unit.  Otherwise gcc

   optimizes away the lineptr == NULL || n == NULL || fp == NULL tests below.  */

#define _GL_ARG_NONNULL(params)

#include <config.h>

#include <stdio.h>

#include <limits.h>

#include <stdint.h>

#include <stdlib.h>

#include <errno.h>

#ifndef SSIZE_MAX

# define SSIZE_MAX ((ssize_t) (SIZE_MAX / 2))

#endif

#if USE_UNLOCKED_IO

# include "unlocked-io.h"

# define getc_maybe_unlocked(fp)        getc(fp)

#elif !HAVE_FLOCKFILE || !HAVE_FUNLOCKFILE || !HAVE_DECL_GETC_UNLOCKED

# undef flockfile

# undef funlockfile

# define flockfile(x) ((void) 0)

# define funlockfile(x) ((void) 0)

# define getc_maybe_unlocked(fp)        getc(fp)

#else

# define getc_maybe_unlocked(fp)        getc_unlocked(fp)

#endif

static void

alloc_failed (void)

{

#if defined _WIN32 && ! defined __CYGWIN__

  /* Avoid errno problem without using the realloc module; see:

     https://lists.gnu.org/r/bug-gnulib/2016-08/msg00025.html  */

  errno = ENOMEM;

#endif

}

/* Read up to (and including) a DELIMITER from FP into *LINEPTR (and

   NUL-terminate it).  *LINEPTR is a pointer returned from malloc (or

   NULL), pointing to *N characters of space.  It is realloc'ed as

   necessary.  Returns the number of characters read (not including

   the null terminator), or -1 on error or EOF.  */

ssize_t

getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)

{

  ssize_t result;

  size_t cur_len = 0;

  if (lineptr == NULL || n == NULL || fp == NULL)

    {

      errno = EINVAL;

      return -1;

    }

  flockfile (fp);

  if (*lineptr == NULL || *n == 0)

    {

      char *new_lineptr;

      *n = 120;

      new_lineptr = (char *) realloc (*lineptr, *n);

      if (new_lineptr == NULL)

        {

          alloc_failed ();

          result = -1;

          goto unlock_return;

        }

      *lineptr = new_lineptr;

    }

  for (;;)

    {

      int i;

      i = getc_maybe_unlocked (fp);

      if (i == EOF)

        {

          result = -1;

          break;

        }

      /* Make enough space for len+1 (for final NUL) bytes.  */

      if (cur_len + 1 >= *n)

        {

          size_t needed_max =

            SSIZE_MAX < SIZE_MAX ? (size_t) SSIZE_MAX + 1 : SIZE_MAX;

          size_t needed = 2 * *n + 1;   /* Be generous. */

          char *new_lineptr;

          if (needed_max < needed)

            needed = needed_max;

          if (cur_len + 1 >= needed)

            {

              result = -1;

              errno = EOVERFLOW;

              goto unlock_return;

            }

          new_lineptr = (char *) realloc (*lineptr, needed);

          if (new_lineptr == NULL)

            {

              alloc_failed ();

              result = -1;

              goto unlock_return;

            }

          *lineptr = new_lineptr;

          *n = needed;

        }

      (*lineptr)[cur_len] = i;

      cur_len++;

      if (i == delimiter)

        break;

    }

  (*lineptr)[cur_len] = '\0';

  result = cur_len ? cur_len : result;

 unlock_return:

  funlockfile (fp); /* doesn't set errno */

  return result;

}