libvirt/tools/nss/libvirt_nss.h
Michal Privoznik 753064963c libvirt_nss: Fix ERROR() macro
The purpose of ERROR() macro in our NSS module is to print error
message provided as arguments followed by error string
corresponding to errno. Historically, we've used strerror_r() for
that (please note, we want our NSS module to be free of libvirt
internal functions, or glib even - hence, g_strerror() is off the
table).

Now strerror_r() is documented as:

  Returns ... a pointer to a string that the function stores in
  buf, or a pointer to some (immutable) static string (in which
  case buf is unused).

Therefore, we can't rely the string being stored in the buf and
really need to store the retval and print that instead.

While touching this area, decrease the ebuf size, since its
current size (1KiB) is triggering our stack limit (2KiB) in some
cases.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2024-04-18 14:57:30 +02:00

92 lines
2.9 KiB
C

/*
* libvirt_nss: Name Service Switch plugin
*
* The aim is to enable users and applications to translate
* domain names into IP addresses. However, this is currently
* available only for those domains which gets their IP addresses
* from a libvirt managed network.
*
* Copyright (C) 2016 Red Hat, Inc.
*
* This 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.
*
* This 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 this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <nss.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#if 0
# include <errno.h>
# include <stdio.h>
# define NULLSTR(s) ((s) ? (s) : "<null>")
# define ERROR(...) \
do { \
char ebuf[512]; \
const char *errmsg = strerror_r(errno, ebuf, sizeof(ebuf)); \
fprintf(stderr, "ERROR %s:%d : ", __FUNCTION__, __LINE__); \
fprintf(stderr, __VA_ARGS__); \
fprintf(stderr, " : %s\n", errmsg); \
fprintf(stderr, "\n"); \
} while (0)
# define DEBUG(...) \
do { \
fprintf(stderr, "DEBUG %s:%d : ", __FUNCTION__, __LINE__); \
fprintf(stderr, __VA_ARGS__); \
fprintf(stderr, "\n"); \
} while (0)
#else
# define ERROR(...) do { } while (0)
# define DEBUG(...) do { } while (0)
#endif
#if !defined(LIBVIRT_NSS_GUEST)
# define NSS_NAME(s) _nss_libvirt_##s##_r
#else
# define NSS_NAME(s) _nss_libvirt_guest_##s##_r
#endif
enum nss_status
NSS_NAME(gethostbyname)(const char *name, struct hostent *result,
char *buffer, size_t buflen, int *errnop,
int *herrnop);
enum nss_status
NSS_NAME(gethostbyname2)(const char *name, int af, struct hostent *result,
char *buffer, size_t buflen, int *errnop,
int *herrnop);
enum nss_status
NSS_NAME(gethostbyname3)(const char *name, int af, struct hostent *result,
char *buffer, size_t buflen, int *errnop,
int *herrnop, int32_t *ttlp, char **canonp);
#ifdef WITH_STRUCT_GAIH_ADDRTUPLE
enum nss_status
NSS_NAME(gethostbyname4)(const char *name, struct gaih_addrtuple **pat,
char *buffer, size_t buflen, int *errnop,
int *herrnop, int32_t *ttlp);
#endif /* WITH_STRUCT_GAIH_ADDRTUPLE */
#if defined(WITH_BSD_NSS)
ns_mtab*
nss_module_register(const char *name, unsigned int *size,
nss_module_unregister_fn *unregister);
#endif /* WITH_BSD_NSS */