Syscall wrappers

Functions
int	vc_syscall (uint32_t cmd, xid_t xid, void *data)
	The generic vserver syscall.
int	vc_get_version ()
	Returns the version of the current kernel API.
xid_t	vc_new_s_context (xid_t ctx, unsigned int remove_cap, unsigned int flags)
	Moves current process into a context.
int	vc_set_ipv4root (uint32_t bcast, size_t nb, struct vc_ip_mask_pair const *ips)
	Sets the ipv4root information.
xid_t	vc_ctx_create (xid_t xid)
	Creates a context without starting it.
int	vc_ctx_migrate (xid_t xid)
	Moves the current process into the specified context.
int	vc_get_rlimit (xid_t xid, int resource, struct vc_rlimit *lim)
	Returns the limits of resource.
int	vc_set_rlimit (xid_t xid, int resource, struct vc_rlimit const *lim)
	Sets the limits of resource.
int	vc_ctx_kill (xid_t ctx, pid_t pid, int sig)
	Sends a signal to a context/pid.
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.
xid_t	vc_get_task_xid (pid_t pid)
	Returns the context of the given process.
xid_t	vc_getfilecontext (char const *filename)
	Returns the context of filename.

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Detailed Description

Functions which are calling the vserver syscall directly.

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Function Documentation

xid_t vc_ctx_create (  xid_t  xid  )

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/pid. Special 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  )

Moves the current process into the specified context. Parameters: xid  The new context 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

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 context. Puts 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_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 syscall. This 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

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