Functions
int	vc_syscall (uint32_t cmd, xid_t xid, void *data)
	The generic vserver syscallThis function executes the generic vserver syscall. It uses the correct syscallnumber (which may differ between the different architectures). More...

int	vc_get_version ()
	Returns the version of the current kernel API. More...

vc_vci_t	vc_get_vci ()
	Returns the kernel configuration bits. More...

xid_t	vc_new_s_context (xid_t ctx, unsigned int remove_cap, unsigned int flags)
	Moves current process into a contextPuts current process into context ctx, removes the capabilities given in remove_cap and sets flags. More...

int	vc_set_ipv4root (uint32_t bcast, size_t nb, struct vc_ip_mask_pair const *ips)
	Sets the ipv4root information. More...

xid_t	vc_ctx_create (xid_t xid, struct vc_ctx_flags *flags)
	Creates a context without starting it.This functions initializes a new context. When already in a freshly created context, this old context will be discarded. More...

int	vc_ctx_migrate (xid_t xid, uint_least64_t flags)
	Moves the current process into the specified context. More...

int	vc_ctx_stat (xid_t xid, struct vc_ctx_stat *stat)
	Get some statistics about a context. More...

int	vc_virt_stat (xid_t xid, struct vc_virt_stat *stat)
	Get more statistics about a context. More...

int	vc_ctx_kill (xid_t ctx, pid_t pid, int sig)
	Sends a signal to a context/pidSpecial values for pid are: More...

xid_t	vc_get_task_xid (pid_t pid)
	Returns the context of the given process. More...

int	vc_wait_exit (xid_t xid)
	Waits for the end of a context.

int	vc_get_rlimit (xid_t xid, int resource, struct vc_rlimit *lim)
	Returns the limits of resource. More...

int	vc_set_rlimit (xid_t xid, int resource, struct vc_rlimit const *lim)
	Sets the limits of resource. More...

int	vc_rlimit_stat (xid_t xid, int resource, struct vc_rlimit_stat *stat)
	Returns the current stats of resource. More...

int	vc_reset_minmax (xid_t xid)
	Resets the minimum and maximum observed values of all resources. More...

int	vc_get_iattr (char const filename, xid_t xid, uint_least32_t flags, uint_least32_t mask)
	Returns information about attributes and assigned context of a file.This function returns the VC_IATTR_XXX flags and about the assigned context of a file. To request an information, the appropriate bit in `mask` must be set and the corresponding parameter (xid or flags) must not be NULL. More...

xid_t	vc_getfilecontext (char const *filename)
	Returns the context of `filename` This function calls vc_get_iattr() with appropriate arguments to determine the context of `filename`. In error-case or when no context is assigned, `VC_NOCTX` will be returned. To differ between both cases, `errno` must be examined. More...

Detailed Description

Functions which are calling the vserver syscall directly.

Function Documentation

xid_t vc_ctx_create	(	xid_t	xid,
		struct vc_ctx_flags *	flags
	)

Creates a context without starting it.This functions initializes a new context. When already in a freshly created context, this old context will be discarded.

Parameters

xid	The new context; special values are: VC_DYNAMIC_XID which means to create a dynamic context

Returns: the xid of the created context, or VC_NOCTX on errors. errno will be set appropriately.

int vc_ctx_kill	(	xid_t	ctx,
		pid_t	pid,
		int	sig
	)

Sends a signal to a context/pidSpecial values for pid are:

-1 which means every process in ctx except the init-process
0 which means every process in ctx inclusive the init-process

int vc_ctx_migrate	(	xid_t	xid,
		uint_least64_t	flags
	)

Moves the current process into the specified context.

Parameters

xid	The new context
flags	The flags, see VC_VXM_*

Returns: 0 on success, -1 on errors

int vc_ctx_stat	(	xid_t	xid,
		struct vc_ctx_stat *	stat
	)

Get some statistics about a context.

Parameters

xid	The context to get stats about
stat	Where to store the result

Returns: 0 on success, -1 on errors.

int vc_get_iattr	(	char const *	filename,
		xid_t *	xid,
		uint_least32_t *	flags,
		uint_least32_t *	mask
	)

Returns information about attributes and assigned context of a file.This function returns the VC_IATTR_XXX flags and about the assigned context of a file. To request an information, the appropriate bit in mask must be set and the corresponding parameter (xid or flags) must not be NULL.

E.g. to receive the assigned context, the VC_IATTR_XID bit must be set in mask, and xid must point to valid memory.

Possible flags are VC_IATTR_ADMIN, VC_IATTR_WATCH , VC_IATTR_HIDE, VC_IATTR_BARRIER, VC_IATTR_IUNLINK and VC_IATTR_IMMUTABLE.

Parameters

filename	The name of the file whose attributes shall be determined.
xid	When non-zero and the VC_IATTR_XID bit is set in mask, the assigned context of filename will be stored there.
flags	When non-zero, a bitmask of current attributes will be stored there. These attributes must be requested explicitly by setting the appropriate bit in mask
mask	Points to a bitmask which tells which attributes shall be determined. On return, it will masquerade the attributes which were determined.

Precondition: mask!=0 && !((*mask&VC_IATTR_XID) && xid==0) && !((*mask&~VC_IATTR_XID) && flags==0)

int vc_get_rlimit	(	xid_t	xid,
		int	resource,
		struct vc_rlimit *	lim
	)

Returns the limits of resource.

Parameters

xid	The id of the context
resource	The resource which will be queried
lim	The result which will be filled with the limits

Returns: 0 on success, and -1 on errors.

xid_t vc_get_task_xid ( pid_t pid )

Returns the context of the given process.

Parameters

pid	the process-id whose xid shall be determined; pid==0 means the current process.

Returns: the xid of process pid or -1 on errors

vc_vci_t vc_get_vci ( )

Returns the kernel configuration bits.

Returns: The kernel configuration bits

int vc_get_version ( )

Returns the version of the current kernel API.

Returns: The versionnumber of the kernel API

xid_t vc_getfilecontext ( char const * filename )

Returns the context of filename This function calls vc_get_iattr() with appropriate arguments to determine the context of filename. In error-case or when no context is assigned, VC_NOCTX will be returned. To differ between both cases, errno must be examined.

WARNING: this function can modify errno although no error happened.

Parameters

filename The file to check

Returns: The assigned context, or VC_NOCTX when an error occured or no such assignment exists. errno will be 0 in the latter case

xid_t vc_new_s_context	(	xid_t	ctx,
		unsigned int	remove_cap,
		unsigned int	flags
	)

Moves current process into a contextPuts current process into context ctx, removes the capabilities given in remove_cap and sets flags.

Parameters

ctx	The new context; special values for are VC_SAMECTX which means the current context (just for changing caps and flags) VC_DYNAMIC_XID which means the next free context; this value can be used by ordinary users also
remove_cap	The linux capabilities which will be removed.
flags	Special flags which will be set.

Returns: The new context-id, or VC_NOCTX on errors; errno will be set appropriately

See http://vserver.13thfloor.at/Stuff/Logic.txt for details

int vc_reset_minmax ( xid_t xid )

Resets the minimum and maximum observed values of all resources.

Parameters

xid	The id of the context

Returns: 0 on success, and -1 on errors.

int vc_rlimit_stat	(	xid_t	xid,
		int	resource,
		struct vc_rlimit_stat *	stat
	)

Returns the current stats of resource.

Parameters

xid	The id of the context
resource	The resource which will be queried
stat	The result which will be filled with the stats

Returns: 0 on success, and -1 on errors.

int vc_set_ipv4root	(	uint32_t	bcast,
		size_t	nb,
		struct vc_ip_mask_pair const *	ips
	)

Sets the ipv4root information.

Precondition: nb < NB_IPV4ROOT && ips != 0

int vc_set_rlimit	(	xid_t	xid,
		int	resource,
		struct vc_rlimit const *	lim
	)

Sets the limits of resource.

Parameters

xid	The id of the context
resource	The resource which will be queried
lim	The new limits

Returns: 0 on success, and -1 on errors.

int vc_syscall	(	uint32_t	cmd,
		xid_t	xid,
		void *	data
	)

The generic vserver syscallThis function executes the generic vserver syscall. It uses the correct syscallnumber (which may differ between the different architectures).

Parameters

cmd	the command to be executed
xid	the xid on which the cmd shall be applied
data	additional arguments; depends on `cmd`

Returns: depends on cmd; usually, -1 stands for an error

int vc_virt_stat	(	xid_t	xid,
		struct vc_virt_stat *	stat
	)

Get more statistics about a context.

Parameters

xid	The context to get stats about
stat	Where to store the result

Returns: 0 on success, -1 on errors.