libvirt/src/util/virutil.h

/*
 * virutil.h: common, generic utility functions
 *
 * Copyright (C) 2010-2014 Red Hat, Inc.
 * Copyright (C) 2006, 2007 Binary Karma
 * Copyright (C) 2006 Shuveb Hussain
 *
 * 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/>.
 *
 * File created Jul 18, 2007 - Shuveb Hussain <shuveb@binarykarma.com>
 */

#ifndef __VIR_UTIL_H__
# define __VIR_UTIL_H__

# include "internal.h"
# include <unistd.h>
# include <sys/types.h>

# ifndef MIN
#  define MIN(a, b) ((a) < (b) ? (a) : (b))
# endif
# ifndef MAX
#  define MAX(a, b) ((a) > (b) ? (a) : (b))
# endif


int virSetBlocking(int fd, bool blocking) ATTRIBUTE_RETURN_CHECK;
int virSetNonBlock(int fd) ATTRIBUTE_RETURN_CHECK;
int virSetInherit(int fd, bool inherit) ATTRIBUTE_RETURN_CHECK;
int virSetCloseExec(int fd) ATTRIBUTE_RETURN_CHECK;
int virSetSockReuseAddr(int fd, bool fatal) ATTRIBUTE_RETURN_CHECK;

int virPipeReadUntilEOF(int outfd, int errfd,
                        char **outbuf, char **errbuf);

int virSetUIDGID(uid_t uid, gid_t gid, gid_t *groups, int ngroups);
int virSetUIDGIDWithCaps(uid_t uid, gid_t gid, gid_t *groups, int ngroups,
                         unsigned long long capBits,
                         bool clearExistingCaps);

int virScaleInteger(unsigned long long *value, const char *suffix,
                    unsigned long long scale, unsigned long long limit)
    ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;

int virHexToBin(unsigned char c);

int virParseNumber(const char **str);
int virParseVersionString(const char *str, unsigned long *version,
                          bool allowMissing);

int virDoubleToStr(char **strp, double number)
    ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;

char *virFormatIntDecimal(char *buf, size_t buflen, int val)
    ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK;

int virDiskNameParse(const char *name, int *disk, int *partition);
int virDiskNameToIndex(const char* str);
char *virIndexToDiskName(int idx, const char *prefix);

int virEnumFromString(const char *const*types,
                      unsigned int ntypes,
                      const char *type);

const char *virEnumToString(const char *const*types,
                            unsigned int ntypes,
                            int type);

# define VIR_ENUM_IMPL(name, lastVal, ...)                               \
    static const char *const name ## TypeList[] = { __VA_ARGS__ };      \
    verify(ARRAY_CARDINALITY(name ## TypeList) == lastVal);             \
    const char *name ## TypeToString(int type) {                        \
        return virEnumToString(name ## TypeList,                        \
                               ARRAY_CARDINALITY(name ## TypeList),     \
                               type);                                   \
    }                                                                   \
    int name ## TypeFromString(const char *type) {                      \
        return virEnumFromString(name ## TypeList,                      \
                                 ARRAY_CARDINALITY(name ## TypeList),   \
                                 type);                                 \
    }

# define VIR_ENUM_DECL(name)                             \
    const char *name ## TypeToString(int type);         \
    int name ## TypeFromString(const char*type);

/* No-op workarounds for functionality missing in mingw.  */
# ifndef HAVE_GETUID
static inline int getuid(void)
{ return 0; }
# endif

# ifndef HAVE_GETEUID
static inline int geteuid(void)
{ return 0; }
# endif

# ifndef HAVE_GETGID
static inline int getgid(void)
{ return 0; }
# endif

# ifndef HAVE_GETEGID
static inline int getegid(void)
{ return 0; }
# endif

# ifdef FUNC_PTHREAD_SIGMASK_BROKEN
#  undef pthread_sigmask
static inline int pthread_sigmask(int how,
                                  const void *set,
                                  void *old)
{
    (void) how;
    (void) set;
    (void) old;
    return 0;
}
# endif

char *virGetHostname(void);
char *virGetHostnameQuiet(void);

char *virGetUserDirectory(void);
char *virGetUserDirectoryByUID(uid_t uid);
char *virGetUserConfigDirectory(void);
char *virGetUserCacheDirectory(void);
char *virGetUserRuntimeDirectory(void);
char *virGetUserShell(uid_t uid);
char *virGetUserName(uid_t uid);
char *virGetGroupName(gid_t gid);
int virGetGroupList(uid_t uid, gid_t group, gid_t **groups)
    ATTRIBUTE_NONNULL(3);
int virGetUserID(const char *name,
                 uid_t *uid) ATTRIBUTE_RETURN_CHECK;
int virGetGroupID(const char *name,
                  gid_t *gid) ATTRIBUTE_RETURN_CHECK;

bool virIsDevMapperDevice(const char *dev_name) ATTRIBUTE_NONNULL(1);

bool virValidateWWN(const char *wwn);

int virGetDeviceID(const char *path,
                   int *maj,
                   int *min);
int virSetDeviceUnprivSGIO(const char *path,
                           const char *sysfs_dir,
                           int unpriv_sgio);
int virGetDeviceUnprivSGIO(const char *path,
                           const char *sysfs_dir,
                           int *unpriv_sgio);
char *virGetUnprivSGIOSysfsPath(const char *path,
                                const char *sysfs_dir);

int virParseOwnershipIds(const char *label, uid_t *uidPtr, gid_t *gidPtr);

const char *virGetEnvBlockSUID(const char *name);
const char *virGetEnvAllowSUID(const char *name);
bool virIsSUID(void);


time_t virGetSelfLastChanged(void);
void virUpdateSelfLastChanged(const char *path);

typedef enum {
    VIR_TRISTATE_BOOL_ABSENT = 0,
    VIR_TRISTATE_BOOL_YES,
    VIR_TRISTATE_BOOL_NO,

    VIR_TRISTATE_BOOL_LAST
} virTristateBool;

typedef enum {
    VIR_TRISTATE_SWITCH_ABSENT = 0,
    VIR_TRISTATE_SWITCH_ON,
    VIR_TRISTATE_SWITCH_OFF,

    VIR_TRISTATE_SWITCH_LAST
} virTristateSwitch;

VIR_ENUM_DECL(virTristateBool)
VIR_ENUM_DECL(virTristateSwitch)

/* the two enums must be in sync to be able to use helpers interchangeably in
 * some special cases */
verify((int)VIR_TRISTATE_BOOL_YES == (int)VIR_TRISTATE_SWITCH_ON);
verify((int)VIR_TRISTATE_BOOL_NO == (int)VIR_TRISTATE_SWITCH_OFF);
verify((int)VIR_TRISTATE_BOOL_ABSENT == (int)VIR_TRISTATE_SWITCH_ABSENT);

unsigned int virGetListenFDs(void);

long virGetSystemPageSize(void);
long virGetSystemPageSizeKB(void);

unsigned long long virMemoryLimitTruncate(unsigned long long value);
bool virMemoryLimitIsSet(unsigned long long value);
unsigned long long virMemoryMaxValue(bool ulong);

/**
 * VIR_ASSIGN_IS_OVERFLOW:
 * @rvalue: value that is checked (evaluated twice)
 * @lvalue: value that the check is against (used in typeof())
 *
 * This macro assigns @lvalue to @rvalue and evaluates as true if the value of
 * @rvalue did not fit into the @lvalue.
 */
# define VIR_ASSIGN_IS_OVERFLOW(lvalue, rvalue)                                \
    (((lvalue) = (rvalue)) != (rvalue))

#endif /* __VIR_UTIL_H__ */