glibc/misc/fstab.c

187 lines
3.8 KiB
C

/* Copyright (C) 1995-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <fstab.h>
#include <mntent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libc-lock.h>
#define BUFFER_SIZE 0x1fc0
struct fstab_state
{
FILE *fs_fp;
char *fs_buffer;
struct mntent fs_mntres;
struct fstab fs_ret;
};
static struct fstab_state *fstab_init (int opt_rewind);
static struct mntent *fstab_fetch (struct fstab_state *state);
static struct fstab *fstab_convert (struct fstab_state *state);
static struct fstab_state fstab_state;
int
setfsent (void)
{
return fstab_init (1) != NULL;
}
struct fstab *
getfsent (void)
{
struct fstab_state *state;
state = fstab_init (0);
if (state == NULL)
return NULL;
if (fstab_fetch (state) == NULL)
return NULL;
return fstab_convert (state);
}
struct fstab *
getfsspec (const char *name)
{
struct fstab_state *state;
struct mntent *m;
state = fstab_init (1);
if (state == NULL)
return NULL;
while ((m = fstab_fetch (state)) != NULL)
if (strcmp (m->mnt_fsname, name) == 0)
return fstab_convert (state);
return NULL;
}
struct fstab *
getfsfile (const char *name)
{
struct fstab_state *state;
struct mntent *m;
state = fstab_init (1);
if (state == NULL)
return NULL;
while ((m = fstab_fetch (state)) != NULL)
if (strcmp (m->mnt_dir, name) == 0)
return fstab_convert (state);
return NULL;
}
void
endfsent (void)
{
struct fstab_state *state;
state = &fstab_state;
if (state->fs_fp != NULL)
{
(void) __endmntent (state->fs_fp);
state->fs_fp = NULL;
}
}
static struct fstab_state *
fstab_init (int opt_rewind)
{
struct fstab_state *state;
char *buffer;
FILE *fp;
state = &fstab_state;
buffer = state->fs_buffer;
if (buffer == NULL)
{
buffer = (char *) malloc (BUFFER_SIZE);
if (buffer == NULL)
return NULL;
state->fs_buffer = buffer;
}
fp = state->fs_fp;
if (fp != NULL)
{
if (opt_rewind)
rewind (fp);
}
else
{
fp = __setmntent (_PATH_FSTAB, "r");
if (fp == NULL)
return NULL;
state->fs_fp = fp;
}
return state;
}
static struct mntent *
fstab_fetch (struct fstab_state *state)
{
return __getmntent_r (state->fs_fp, &state->fs_mntres,
state->fs_buffer, BUFFER_SIZE);
}
static struct fstab *
fstab_convert (struct fstab_state *state)
{
struct mntent *m;
struct fstab *f;
m = &state->fs_mntres;
f = &state->fs_ret;
f->fs_spec = m->mnt_fsname;
f->fs_file = m->mnt_dir;
f->fs_vfstype = m->mnt_type;
f->fs_mntops = m->mnt_opts;
f->fs_type = (__hasmntopt (m, FSTAB_RW) ? FSTAB_RW :
__hasmntopt (m, FSTAB_RQ) ? FSTAB_RQ :
__hasmntopt (m, FSTAB_RO) ? FSTAB_RO :
__hasmntopt (m, FSTAB_SW) ? FSTAB_SW :
__hasmntopt (m, FSTAB_XX) ? FSTAB_XX :
"??");
f->fs_freq = m->mnt_freq;
f->fs_passno = m->mnt_passno;
return f;
}
/* Make sure the memory is freed if the programs ends while in
memory-debugging mode and something actually was allocated. */
libc_freeres_fn (fstab_free)
{
char *buffer;
buffer = fstab_state.fs_buffer;
free ((void *) buffer);
}