libvirt/src/util/virfile.h
Daniel P. Berrange a261996255 Introduce virFilePrintf() as a portable fprintf()
We can't use GNULIB's fprintf-posix due to licensing
incompatibilities. We do already have a portable
formatting via virAsprintf() which we got from GNULIB
though. We can use to create a virFilePrintf() function.

But really gnulib could just provide a 'fprintf'
module, that depended on just its 'asprintf' module.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-05-31 10:51:33 -06:00

236 lines
8.1 KiB
C

/*
* virfile.h: safer file handling
*
* Copyright (C) 2010-2011, 2013 Red Hat, Inc.
* Copyright (C) 2010 IBM Corporation
* Copyright (C) 2010 Stefan Berger
* Copyright (C) 2010 Eric Blake
*
* 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_H_
# define __VIR_FILE_H_
# include <stdio.h>
# include "internal.h"
# include "virstoragefile.h"
typedef enum virFileCloseFlags {
VIR_FILE_CLOSE_PRESERVE_ERRNO = 1 << 0,
VIR_FILE_CLOSE_IGNORE_EBADF = 1 << 1,
VIR_FILE_CLOSE_DONT_LOG = 1 << 2,
} virFileCloseFlags;
ssize_t saferead(int fd, void *buf, size_t count) ATTRIBUTE_RETURN_CHECK;
ssize_t safewrite(int fd, const void *buf, size_t count)
ATTRIBUTE_RETURN_CHECK;
int safezero(int fd, off_t offset, off_t len)
ATTRIBUTE_RETURN_CHECK;
/* Don't call these directly - use the macros below */
int virFileClose(int *fdptr, virFileCloseFlags flags)
ATTRIBUTE_RETURN_CHECK;
int virFileFclose(FILE **file, bool preserve_errno) ATTRIBUTE_RETURN_CHECK;
FILE *virFileFdopen(int *fdptr, const char *mode) ATTRIBUTE_RETURN_CHECK;
/* For use on normal paths; caller must check return value,
and failure sets errno per close. */
# define VIR_CLOSE(FD) virFileClose(&(FD), 0)
# define VIR_FCLOSE(FILE) virFileFclose(&(FILE), false)
/* Wrapper around fdopen that consumes fd on success. */
# define VIR_FDOPEN(FD, MODE) virFileFdopen(&(FD), MODE)
/* For use on cleanup paths; errno is unaffected by close,
and no return value to worry about. */
# define VIR_FORCE_CLOSE(FD) \
ignore_value(virFileClose(&(FD), VIR_FILE_CLOSE_PRESERVE_ERRNO))
# define VIR_FORCE_FCLOSE(FILE) ignore_value(virFileFclose(&(FILE), true))
/* Similar VIR_FORCE_CLOSE() but ignores EBADF errors since they are expected
* during mass close after fork(). */
# define VIR_MASS_CLOSE(FD) \
ignore_value(virFileClose(&(FD), \
VIR_FILE_CLOSE_PRESERVE_ERRNO | \
VIR_FILE_CLOSE_IGNORE_EBADF))
# define VIR_LOG_CLOSE(FD) \
ignore_value(virFileClose(&(FD), \
VIR_FILE_CLOSE_PRESERVE_ERRNO | \
VIR_FILE_CLOSE_DONT_LOG))
/* Opaque type for managing a wrapper around a fd. */
struct _virFileWrapperFd;
typedef struct _virFileWrapperFd virFileWrapperFd;
typedef virFileWrapperFd *virFileWrapperFdPtr;
int virFileDirectFdFlag(void);
enum virFileWrapperFdFlags {
VIR_FILE_WRAPPER_BYPASS_CACHE = (1 << 0),
VIR_FILE_WRAPPER_NON_BLOCKING = (1 << 1),
};
virFileWrapperFdPtr virFileWrapperFdNew(int *fd,
const char *name,
unsigned int flags)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;
int virFileWrapperFdClose(virFileWrapperFdPtr dfd);
void virFileWrapperFdFree(virFileWrapperFdPtr dfd);
int virFileLock(int fd, bool shared, off_t start, off_t len);
int virFileUnlock(int fd, off_t start, off_t len);
typedef int (*virFileRewriteFunc)(int fd, void *opaque);
int virFileRewrite(const char *path,
mode_t mode,
virFileRewriteFunc rewrite,
void *opaque);
int virFileTouch(const char *path, mode_t mode);
int virFileUpdatePerm(const char *path,
mode_t mode_remove,
mode_t mode_add);
int virFileLoopDeviceAssociate(const char *file,
char **dev);
int virFileNBDDeviceAssociate(const char *file,
enum virStorageFileFormat fmt,
bool readonly,
char **dev);
int virFileDeleteTree(const char *dir);
int virFileReadLimFD(int fd, int maxlen, char **buf) ATTRIBUTE_RETURN_CHECK;
int virFileReadAll(const char *path, int maxlen, char **buf) ATTRIBUTE_RETURN_CHECK;
int virFileWriteStr(const char *path, const char *str, mode_t mode)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;
int virFileMatchesNameSuffix(const char *file,
const char *name,
const char *suffix);
int virFileHasSuffix(const char *str,
const char *suffix);
int virFileStripSuffix(char *str,
const char *suffix) ATTRIBUTE_RETURN_CHECK;
int virFileLinkPointsTo(const char *checkLink,
const char *checkDest);
int virFileResolveLink(const char *linkpath,
char **resultpath) ATTRIBUTE_RETURN_CHECK;
int virFileResolveAllLinks(const char *linkpath,
char **resultpath) ATTRIBUTE_RETURN_CHECK;
int virFileIsLink(const char *linkpath)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;
char *virFindFileInPath(const char *file);
bool virFileIsDir (const char *file) ATTRIBUTE_NONNULL(1);
bool virFileExists(const char *file) ATTRIBUTE_NONNULL(1);
bool virFileIsExecutable(const char *file) ATTRIBUTE_NONNULL(1);
char *virFileSanitizePath(const char *path);
enum {
VIR_FILE_OPEN_NONE = 0,
VIR_FILE_OPEN_NOFORK = (1 << 0),
VIR_FILE_OPEN_FORK = (1 << 1),
VIR_FILE_OPEN_FORCE_MODE = (1 << 2),
VIR_FILE_OPEN_FORCE_OWNER = (1 << 3),
};
int virFileAccessibleAs(const char *path, int mode,
uid_t uid, gid_t gid)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;
int virFileOpenAs(const char *path, int openflags, mode_t mode,
uid_t uid, gid_t gid,
unsigned int flags)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;
enum {
VIR_DIR_CREATE_NONE = 0,
VIR_DIR_CREATE_AS_UID = (1 << 0),
VIR_DIR_CREATE_FORCE_PERMS = (1 << 1),
VIR_DIR_CREATE_ALLOW_EXIST = (1 << 2),
};
int virDirCreate(const char *path, mode_t mode, uid_t uid, gid_t gid,
unsigned int flags) ATTRIBUTE_RETURN_CHECK;
int virFileMakePath(const char *path) ATTRIBUTE_RETURN_CHECK;
int virFileMakePathWithMode(const char *path,
mode_t mode) ATTRIBUTE_RETURN_CHECK;
char *virFileBuildPath(const char *dir,
const char *name,
const char *ext) ATTRIBUTE_RETURN_CHECK;
# ifdef WIN32
/* On Win32, the canonical directory separator is the backslash, and
* the search path separator is the semicolon. Note that also the
* (forward) slash works as directory separator.
*/
# define VIR_FILE_DIR_SEPARATOR '\\'
# define VIR_FILE_DIR_SEPARATOR_S "\\"
# define VIR_FILE_IS_DIR_SEPARATOR(c) ((c) == VIR_FILE_DIR_SEPARATOR || (c) == '/')
# define VIR_FILE_PATH_SEPARATOR ';'
# define VIR_FILE_PATH_SEPARATOR_S ";"
# else /* !WIN32 */
# define VIR_FILE_DIR_SEPARATOR '/'
# define VIR_FILE_DIR_SEPARATOR_S "/"
# define VIR_FILE_IS_DIR_SEPARATOR(c) ((c) == VIR_FILE_DIR_SEPARATOR)
# define VIR_FILE_PATH_SEPARATOR ':'
# define VIR_FILE_PATH_SEPARATOR_S ":"
# endif /* !WIN32 */
bool virFileIsAbsPath(const char *path);
int virFileAbsPath(const char *path,
char **abspath) ATTRIBUTE_RETURN_CHECK;
const char *virFileSkipRoot(const char *path);
int virFileOpenTty(int *ttymaster,
char **ttyName,
int rawmode);
char *virFileFindMountPoint(const char *type);
void virFileWaitForDevices(void);
/* NB: this should be combined with virFileBuildPath */
# define virBuildPath(path, ...) \
virBuildPathInternal(path, __VA_ARGS__, NULL)
int virBuildPathInternal(char **path, ...) ATTRIBUTE_SENTINEL;
int virFilePrintf(FILE *fp, const char *msg, ...)
ATTRIBUTE_FMT_PRINTF(2, 3);
#endif /* __VIR_FILE_H */