grub/grub-core/gnulib/getdelim.c
Vladimir 'phcoder' Serbinenko 053cfcddf1 Import new gnulib.
2013-04-11 21:12:46 +02:00

135 lines
3.5 KiB
C

/* getdelim.c --- Implementation of replacement getdelim function.
Copyright (C) 1994, 1996-1998, 2001, 2003, 2005-2013 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 <http://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
/* 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)
{
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)
{
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;
}