Systemd/src/basic/glob-util.c
Lennart Poettering 544e146b0e journalctl,elsewhere: make sure --file=foo fails with sane error msg if foo is not readable
It annoyed me for quite a while that running "journalctl --file=…" on a
file that is not readable failed with a "File not found" error instead
of a permission error. Let's fix that.

We make this work by using the GLOB_NOCHECK flag for glob() which means
that files are not accessible will be returned in the array as they are
instead of being filtered away. This then means that our later attemps
to open the files will fail cleanly with a good error message.
2020-05-19 15:26:51 +02:00

74 lines
1.9 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "dirent-util.h"
#include "errno-util.h"
#include "glob-util.h"
#include "macro.h"
#include "path-util.h"
#include "strv.h"
static void closedir_wrapper(void* v) {
(void) closedir(v);
}
int safe_glob(const char *path, int flags, glob_t *pglob) {
int k;
/* We want to set GLOB_ALTDIRFUNC ourselves, don't allow it to be set. */
assert(!(flags & GLOB_ALTDIRFUNC));
if (!pglob->gl_closedir)
pglob->gl_closedir = closedir_wrapper;
if (!pglob->gl_readdir)
pglob->gl_readdir = (struct dirent *(*)(void *)) readdir_no_dot;
if (!pglob->gl_opendir)
pglob->gl_opendir = (void *(*)(const char *)) opendir;
if (!pglob->gl_lstat)
pglob->gl_lstat = lstat;
if (!pglob->gl_stat)
pglob->gl_stat = stat;
errno = 0;
k = glob(path, flags | GLOB_ALTDIRFUNC, NULL, pglob);
if (k == GLOB_NOMATCH)
return -ENOENT;
if (k == GLOB_NOSPACE)
return -ENOMEM;
if (k != 0)
return errno_or_else(EIO);
if (strv_isempty(pglob->gl_pathv))
return -ENOENT;
return 0;
}
int glob_exists(const char *path) {
_cleanup_globfree_ glob_t g = {};
int k;
assert(path);
k = safe_glob(path, GLOB_NOSORT|GLOB_BRACE, &g);
if (k == -ENOENT)
return false;
if (k < 0)
return k;
return true;
}
int glob_extend(char ***strv, const char *path, int flags) {
_cleanup_globfree_ glob_t g = {};
int k;
k = safe_glob(path, GLOB_NOSORT|GLOB_BRACE|flags, &g);
if (k < 0)
return k;
return strv_extend_strv(strv, g.gl_pathv, false);
}