tests: Add virfilewrapper -- the new super "mock"

This mock (which is actually not mock at all, see later) can redirect
all accesses to a path into another path.  There is no need to
create mocks for particular directories, you just create a directory
with all the data a redirect the test there.

In the future, this should also be able to register callbacks for
calls/paths, e.g. when the test is going to write into anything under
"/sys/devices", call function fce();  Then in the open() call we would
add information about the fd into some structure and in write() we
would call fce() with parameters like @path to write to, @data to
be written and pointer to optional return value, so that fce() itself
could stop the call from happening or change its behaviour.  But
that's an idea for a latter day.

This is not a mock because it will not be preloaded, but compiled in
the test itself.  See future patches for usage.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
This commit is contained in:
Martin Kletzander 2017-04-03 14:29:45 +02:00
parent 8fc72e1c72
commit ae60ea48bc
4 changed files with 310 additions and 3 deletions

4
cfg.mk
View File

@ -1129,7 +1129,7 @@ exclude_file_name_regexp--sc_copyright_usage = \
^COPYING(|\.LESSER)$$
exclude_file_name_regexp--sc_flags_usage = \
^(cfg\.mk|docs/|src/util/virnetdevtap\.c$$|tests/(vir(cgroup|pci|test|usb)|nss|qemuxml2argv)mock\.c$$)
^(cfg\.mk|docs/|src/util/virnetdevtap\.c$$|tests/((vir(cgroup|pci|test|usb)|nss|qemuxml2argv)mock|virfilewrapper)\.c$$)
exclude_file_name_regexp--sc_libvirt_unmarked_diagnostics = \
^(src/rpc/gendispatch\.pl$$|tests/)
@ -1258,7 +1258,7 @@ exclude_file_name_regexp--sc_prohibit_always-defined_macros = \
^tests/virtestmock.c$$
exclude_file_name_regexp--sc_prohibit_readdir = \
^tests/.*mock\.c$$
^tests/(.*mock|virfilewrapper)\.c$$
exclude_file_name_regexp--sc_prohibit_cross_inclusion = \
^(src/util/virclosecallbacks\.h|src/util/virhostdev\.h)$$

View File

@ -1156,7 +1156,7 @@ virnumamock_la_CFLAGS = $(AM_CFLAGS)
virnumamock_la_LDFLAGS = $(MOCKLIBS_LDFLAGS)
virnumamock_la_LIBADD = $(MOCKLIBS_LIBS)
else ! WITH_LINUX
EXTRA_DIST += vircaps2xmltest.c virnumamock.c
EXTRA_DIST += vircaps2xmltest.c virnumamock.c virfilewrapper.c virfilewrapper.h
endif ! WITH_LINUX
if WITH_NSS

276
tests/virfilewrapper.c Normal file
View File

@ -0,0 +1,276 @@
/*
* virfilewrapper.c: Wrapper for universal file access
*
* 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/>.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include "viralloc.h"
#include "virfile.h"
#include "virfilewrapper.h"
#include "virmock.h"
#include "virstring.h"
/* Mapping for prefix overrides */
static size_t noverrides;
static const char **overrides;
/* nprefixes == noverrides, but two variables make it easier to use
* VIR_*_ELEMENT macros */
static size_t nprefixes;
static const char **prefixes;
/* TODO: callbacks */
static int (*real_open)(const char *path, int flags, ...);
static FILE *(*real_fopen)(const char *path, const char *mode);
static int (*real_access)(const char *path, int mode);
static int (*real_stat)(const char *path, struct stat *sb);
static int (*real___xstat)(int ver, const char *path, struct stat *sb);
static int (*real_lstat)(const char *path, struct stat *sb);
static int (*real___lxstat)(int ver, const char *path, struct stat *sb);
static int (*real_mkdir)(const char *path, mode_t mode);
static DIR *(*real_opendir)(const char *path);
static void init_syms(void)
{
if (real_fopen)
return;
VIR_MOCK_REAL_INIT(fopen);
VIR_MOCK_REAL_INIT(access);
VIR_MOCK_REAL_INIT_ALT(lstat, __lxstat);
VIR_MOCK_REAL_INIT_ALT(stat, __xstat);
VIR_MOCK_REAL_INIT(mkdir);
VIR_MOCK_REAL_INIT(open);
VIR_MOCK_REAL_INIT(opendir);
}
int
virFileWrapperAddPrefix(const char *prefix,
const char *override)
{
/* Both parameters are mandatory */
if (!prefix || !override)
return -1;
init_syms();
if (VIR_APPEND_ELEMENT_QUIET(prefixes, nprefixes, prefix) < 0 ||
VIR_APPEND_ELEMENT_QUIET(overrides, noverrides, override) < 0) {
VIR_FREE(prefixes);
VIR_FREE(overrides);
return -1;
}
return 0;
}
void
virFileWrapperRemovePrefix(const char *prefix)
{
size_t i = 0;
for (i = 0; i < noverrides; i++) {
if (STREQ(prefixes[i], prefix))
break;
}
if (i == noverrides)
return;
VIR_DELETE_ELEMENT(overrides, i, noverrides);
VIR_DELETE_ELEMENT(prefixes, i, nprefixes);
}
void
virFileWrapperClearPrefixes(void)
{
nprefixes = 0;
noverrides = 0;
VIR_FREE(prefixes);
VIR_FREE(overrides);
}
static char *
virFileWrapperOverridePrefix(const char *path)
{
char *ret = NULL;
size_t i = 0;
for (i = 0; i < noverrides; i++) {
const char *tmp = STRSKIP(path, prefixes[i]);
if (!tmp)
continue;
if (virAsprintfQuiet(&ret, "%s%s", overrides[i], tmp) < 0)
return NULL;
break;
}
if (!ret)
ignore_value(VIR_STRDUP_QUIET(ret, path));
return ret;
}
#define PATH_OVERRIDE(newpath, path) \
do { \
init_syms(); \
\
newpath = virFileWrapperOverridePrefix(path); \
if (!newpath) \
abort(); \
} while (0)
FILE *fopen(const char *path, const char *mode)
{
FILE *ret = NULL;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_fopen(newpath, mode);
VIR_FREE(newpath);
return ret;
}
int access(const char *path, int mode)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_access(newpath, mode);
VIR_FREE(newpath);
return ret;
}
int __lxstat(int ver, const char *path, struct stat *sb)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real___lxstat(ver, newpath, sb);
VIR_FREE(newpath);
return ret;
}
int lstat(const char *path, struct stat *sb)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_lstat(newpath, sb);
VIR_FREE(newpath);
return ret;
}
int __xstat(int ver, const char *path, struct stat *sb)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real___xstat(ver, newpath, sb);
VIR_FREE(newpath);
return ret;
}
int stat(const char *path, struct stat *sb)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_stat(newpath, sb);
VIR_FREE(newpath);
return ret;
}
int mkdir(const char *path, mode_t mode)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_mkdir(newpath, mode);
VIR_FREE(newpath);
return ret;
}
int open(const char *path, int flags, ...)
{
int ret = -1;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_open(newpath, flags);
VIR_FREE(newpath);
return ret;
}
DIR *opendir(const char *path)
{
DIR *ret = NULL;
char *newpath = NULL;
PATH_OVERRIDE(newpath, path);
ret = real_opendir(newpath);
VIR_FREE(newpath);
return ret;
}

31
tests/virfilewrapper.h Normal file
View File

@ -0,0 +1,31 @@
/*
* virfilewrapper.h: Wrapper for universal file access
*
* 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/>.
*/
#ifndef __VIR_FILE_MOCK_H__
int
virFileWrapperAddPrefix(const char *prefix,
const char *override);
void
virFileWrapperRemovePrefix(const char *prefix);
void
virFileWrapperClearPrefixes(void);
#endif /* __VIR_FILE_MOCK_H__ */