kdbmeta.h File Reference

metadata functions More...

#include "kdb.h"

Include dependency graph for kdbmeta.h:

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Functions
const char *	keyOwner (const Key *key)
	Return a pointer to the real internal key owner. More...
ssize_t	keyGetOwnerSize (const Key *key)
	Return the size of the owner of the Key with concluding 0. More...
ssize_t	keyGetOwner (const Key *key, char *returned, size_t maxSize)
	Return the owner of the key. More...
ssize_t	keySetOwner (Key *key, const char *owner)
	Set the owner of a key. More...
const char *	keyComment (const Key *key)
	Return a pointer to the real internal key comment. More...
ssize_t	keyGetCommentSize (const Key *key)
	Calculates number of bytes needed to store a key comment, including final NULL. More...
ssize_t	keyGetComment (const Key *key, char *returnedDesc, size_t maxSize)
	Get the key comment. More...
ssize_t	keySetComment (Key *key, const char *newDesc)
	Set a comment for a key. More...
uid_t	keyGetUID (const Key *key)
	Get the user ID of a key. More...
int	keySetUID (Key *key, uid_t uid)
	Set the user ID of a key. More...
gid_t	keyGetGID (const Key *key)
	Get the group ID of a key. More...
int	keySetGID (Key *key, gid_t gid)
	Set the group ID of a key. More...
int	keySetDir (Key *key)
	Set mode so that key will be recognized as directory. More...
mode_t	keyGetMode (const Key *key)
	Return the key mode permissions. More...
int	keySetMode (Key *key, mode_t mode)
	Set the key mode permissions. More...
time_t	keyGetATime (const Key *key)
	Get last time the key data was read from disk. More...
int	keySetATime (Key *key, time_t atime)
	Update the atime information for a key. More...
time_t	keyGetMTime (const Key *key)
	Get last modification time of the key on disk. More...
int	keySetMTime (Key *key, time_t mtime)
	Update the mtime information for a key. More...
time_t	keyGetCTime (const Key *key)
	Get last time the key metadata was changed from disk. More...
int	keySetCTime (Key *key, time_t ctime)
	Update the ctime information for a key. More...
int	elektraKeyCmpOrder (const Key *a, const Key *b)
	Compare the order metadata of two keys. More...
KeySet *	elektraMetaArrayToKS (const Key *, const char *)
	Create a KeySet from a metakey array. More...
void	elektraMetaArrayAdd (Key *, const char *, const char *)
	creates an metadata array or appends another element to an existing metadata array e.g. More...
char *	elektraMetaArrayToString (const Key *, const char *, const char *)
	returns the metakey array as a string separated by delim More...
int	elektraSortTopology (KeySet *, Key **)
	topological sorting More...

Detailed Description

metadata functions

These functions might be removed in a later version.

Copyright

BSD License (see LICENSE.md or https://www.libelektra.org)

Function Documentation

keyGetOwner()

ssize_t keyGetOwner	(	const Key *	key,
		char *	returnedOwner,
		size_t	maxSize
	)

Return the owner of the key.

• Given user:someuser/..... return someuser
• Given user:some.user/.... return some.user
• Given user/.... return the current user

Only user/... keys have an owner. For system/... keys (that doesn't have a key owner) an empty string ("") is returned.

Although usually the same, the owner of a key is not related to its UID. Owner are related to WHERE the key is stored on disk, while UIDs are related to mode controls of a key.

Parameters

key	the object to work with
returnedOwner	a pre-allocated space to store the owner
maxSize	maximum number of bytes that fit returned

Returns

number of bytes written to buffer

Return values

1	if there is no owner
-1	on NULL pointers
-1	when maxSize is 0, larger than SSIZE_MAX or too small for ownername

See also

keySetName(), keySetOwner(), keyOwner(), keyGetFullName()

keyGetOwnerSize()

ssize_t keyGetOwnerSize

(

const Key *

key

)

Return the size of the owner of the Key with concluding 0.

The returned number can be used to allocate a string. 1 will returned on an empty owner to store the concluding 0 on using keyGetOwner().

char * buffer;
buffer = elektraMalloc (keyGetOwnerSize (key));
// use buffer and keyGetOwnerSize (key) for maxSize

Note

that -1 might be returned on null pointer, so when you directly allocate afterwards its best to check if you will pass a null pointer before.

Parameters

key	the key object to work with

Returns

number of bytes

Return values

1	if there is no owner
-1	on NULL pointer

See also

keyGetOwner()

keyOwner()

const char* keyOwner

(

const Key *

key

)

Return a pointer to the real internal key owner.

This is a much more efficient version of keyGetOwner() and you should use it if you are responsible enough to not mess up things. You are not allowed to modify the returned string in any way. If you need a copy of the string, consider to use keyGetOwner() instead.

keyOwner() returns "" when there is no keyOwner. The reason is

key=keyNew(0);
keySetOwner(key,"");
keyOwner(key); // you would expect "" here
keySetOwner(key,"system");
keyOwner(key); // you would expect "" here

Note

Note that the Key structure keeps its own size field that is calculated by library internal calls, so to avoid inconsistencies, you must never use the pointer returned by keyOwner() method to set a new value. Use keySetOwner() instead.

Parameters

key	the key object to work with

Returns

a pointer to internal owner

Return values

""	when there is no (an empty) owner
0	iff key is a NULL pointer

See also

keyGetOwnerSize() for the size of the string with concluding 0

keyGetOwner(), keySetOwner()

keyName() for name without owner

keyGetFullName() for name with owner

keySetOwner()

ssize_t keySetOwner	(	Key *	key,
		const char *	newOwner
	)

Set the owner of a key.

an owner is a name of a system user related to a UID. The owner decides on which location on the disc the key goes.

A private copy is stored, so the passed parameter can be freed after the call.

Parameters

key	the key object to work with
newOwner	the string which describes the owner of the key

Returns

the number of bytes actually saved including final NULL

Return values

1	when owner is freed (by setting 0 or "")
-1	on null pointer or memory problems

See also

keySetName(), keyGetOwner(), keyGetFullName()