mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-29 05:51:10 +00:00
223 lines
6.3 KiB
C
223 lines
6.3 KiB
C
/* Common code for file-based databases in nss_files module.
|
||
Copyright (C) 1996-2023 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
|
||
<https://www.gnu.org/licenses/>. */
|
||
|
||
#include <stdio.h>
|
||
#include <ctype.h>
|
||
#include <errno.h>
|
||
#include <fcntl.h>
|
||
#include <libc-lock.h>
|
||
#include "nsswitch.h"
|
||
#include <nss_files.h>
|
||
|
||
#include <kernel-features.h>
|
||
|
||
/* These symbols are defined by the including source file:
|
||
|
||
ENTNAME -- database name of the structure and functions (hostent, pwent).
|
||
STRUCTURE -- struct name, define only if not ENTNAME (passwd, group).
|
||
DATABASE -- string of the database file's name ("hosts", "passwd").
|
||
|
||
NEED_H_ERRNO - defined iff an arg `int *herrnop' is used.
|
||
|
||
Also see files-parse.c.
|
||
*/
|
||
|
||
#define ENTNAME_r CONCAT(ENTNAME,_r)
|
||
|
||
#define DATAFILE "/etc/" DATABASE
|
||
|
||
#ifdef NEED_H_ERRNO
|
||
# include <netdb.h>
|
||
# define H_ERRNO_PROTO , int *herrnop
|
||
# define H_ERRNO_ARG , herrnop
|
||
# define H_ERRNO_ARG_OR_NULL herrnop
|
||
# define H_ERRNO_SET(val) (*herrnop = (val))
|
||
#else
|
||
# define H_ERRNO_PROTO
|
||
# define H_ERRNO_ARG
|
||
# define H_ERRNO_ARG_OR_NULL NULL
|
||
# define H_ERRNO_SET(val) ((void) 0)
|
||
#endif
|
||
|
||
#ifndef EXTRA_ARGS
|
||
# define EXTRA_ARGS
|
||
# define EXTRA_ARGS_DECL
|
||
# define EXTRA_ARGS_VALUE
|
||
#endif
|
||
|
||
|
||
/* Maintenance of the stream open on the database file. For getXXent
|
||
operations the stream needs to be held open across calls, the other
|
||
getXXbyYY operations all use their own stream. */
|
||
|
||
/* Open database file if not already opened. */
|
||
static enum nss_status
|
||
internal_setent (FILE **stream)
|
||
{
|
||
enum nss_status status = NSS_STATUS_SUCCESS;
|
||
|
||
if (*stream == NULL)
|
||
{
|
||
*stream = __nss_files_fopen (DATAFILE);
|
||
|
||
if (*stream == NULL)
|
||
status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
|
||
}
|
||
else
|
||
rewind (*stream);
|
||
|
||
return status;
|
||
}
|
||
|
||
|
||
/* Thread-safe, exported version of that. */
|
||
enum nss_status
|
||
CONCAT(_nss_files_set,ENTNAME) (int stayopen)
|
||
{
|
||
return __nss_files_data_setent (CONCAT (nss_file_, ENTNAME), DATAFILE);
|
||
}
|
||
libc_hidden_def (CONCAT (_nss_files_set,ENTNAME))
|
||
|
||
enum nss_status
|
||
CONCAT(_nss_files_end,ENTNAME) (void)
|
||
{
|
||
return __nss_files_data_endent (CONCAT (nss_file_, ENTNAME));
|
||
}
|
||
libc_hidden_def (CONCAT (_nss_files_end,ENTNAME))
|
||
|
||
|
||
/* Parsing the database file into `struct STRUCTURE' data structures. */
|
||
static enum nss_status
|
||
internal_getent (FILE *stream, struct STRUCTURE *result,
|
||
char *buffer, size_t buflen, int *errnop H_ERRNO_PROTO
|
||
EXTRA_ARGS_DECL)
|
||
{
|
||
struct parser_data *data = (void *) buffer;
|
||
size_t linebuflen = buffer + buflen - data->linebuffer;
|
||
int saved_errno = errno; /* Do not clobber errno on success. */
|
||
|
||
if (buflen < sizeof *data + 2)
|
||
{
|
||
*errnop = ERANGE;
|
||
H_ERRNO_SET (NETDB_INTERNAL);
|
||
return NSS_STATUS_TRYAGAIN;
|
||
}
|
||
|
||
while (true)
|
||
{
|
||
off64_t original_offset;
|
||
int ret = __nss_readline (stream, data->linebuffer, linebuflen,
|
||
&original_offset);
|
||
if (ret == ENOENT)
|
||
{
|
||
/* End of file. */
|
||
H_ERRNO_SET (HOST_NOT_FOUND);
|
||
__set_errno (saved_errno);
|
||
return NSS_STATUS_NOTFOUND;
|
||
}
|
||
else if (ret == 0)
|
||
{
|
||
ret = __nss_parse_line_result (stream, original_offset,
|
||
parse_line (data->linebuffer,
|
||
result, data, buflen,
|
||
errnop EXTRA_ARGS));
|
||
if (ret == 0)
|
||
{
|
||
/* Line has been parsed successfully. */
|
||
__set_errno (saved_errno);
|
||
return NSS_STATUS_SUCCESS;
|
||
}
|
||
else if (ret == EINVAL)
|
||
/* If it is invalid, loop to get the next line of the file
|
||
to parse. */
|
||
continue;
|
||
}
|
||
|
||
*errnop = ret;
|
||
H_ERRNO_SET (NETDB_INTERNAL);
|
||
if (ret == ERANGE)
|
||
/* Request larger buffer. */
|
||
return NSS_STATUS_TRYAGAIN;
|
||
else
|
||
/* Other read failure. */
|
||
return NSS_STATUS_UNAVAIL;
|
||
}
|
||
}
|
||
|
||
|
||
/* Return the next entry from the database file, doing locking. */
|
||
enum nss_status
|
||
CONCAT(_nss_files_get,ENTNAME_r) (struct STRUCTURE *result, char *buffer,
|
||
size_t buflen, int *errnop H_ERRNO_PROTO)
|
||
{
|
||
/* Return next entry in host file. */
|
||
|
||
struct nss_files_per_file_data *data;
|
||
enum nss_status status = __nss_files_data_open (&data,
|
||
CONCAT (nss_file_, ENTNAME),
|
||
DATAFILE,
|
||
errnop, H_ERRNO_ARG_OR_NULL);
|
||
if (status != NSS_STATUS_SUCCESS)
|
||
return status;
|
||
|
||
status = internal_getent (data->stream, result, buffer, buflen, errnop
|
||
H_ERRNO_ARG EXTRA_ARGS_VALUE);
|
||
|
||
__nss_files_data_put (data);
|
||
return status;
|
||
}
|
||
libc_hidden_def (CONCAT (_nss_files_get,ENTNAME_r))
|
||
|
||
/* Macro for defining lookup functions for this file-based database.
|
||
|
||
NAME is the name of the lookup; e.g. `hostbyname'.
|
||
|
||
DB_CHAR, KEYPATTERN, KEYSIZE are ignored here but used by db-XXX.c
|
||
e.g. `1 + sizeof (id) * 4'.
|
||
|
||
PROTO is the potentially empty list of other parameters.
|
||
|
||
BREAK_IF_MATCH is a block of code which compares `struct STRUCTURE *result'
|
||
to the lookup key arguments and does `break;' if they match. */
|
||
|
||
#define DB_LOOKUP(name, db_char, keysize, keypattern, break_if_match, proto...)\
|
||
enum nss_status \
|
||
_nss_files_get##name##_r (proto, \
|
||
struct STRUCTURE *result, char *buffer, \
|
||
size_t buflen, int *errnop H_ERRNO_PROTO) \
|
||
{ \
|
||
enum nss_status status; \
|
||
FILE *stream = NULL; \
|
||
\
|
||
/* Open file. */ \
|
||
status = internal_setent (&stream); \
|
||
\
|
||
if (status == NSS_STATUS_SUCCESS) \
|
||
{ \
|
||
while ((status = internal_getent (stream, result, buffer, buflen, errnop \
|
||
H_ERRNO_ARG EXTRA_ARGS_VALUE)) \
|
||
== NSS_STATUS_SUCCESS) \
|
||
{ break_if_match } \
|
||
\
|
||
fclose (stream); \
|
||
} \
|
||
\
|
||
return status; \
|
||
} \
|
||
libc_hidden_def (_nss_files_get##name##_r)
|