generic.h File Reference

This file contains declarations needed by both the userspace public interface and the Linux kernel implementation. More...

Go to the source code of this file.

Data Structures
struct	achk_opt
	Struct containing 'cache' of kernel module data to avoid updating when no changes exist. More...

Macros
#define	ACH_WARN_UNUSED
	Warn if result is unused.
#define	ACH_STALE_FRAMES   ACH_EAGAIN
#define	ACH_LOCKED   ACH_EAGAIN
#define	ACH_STATUS_MASK(r)   (1<<(r))
	Generate a bit mask from an ach status type. More...
#define	ACH_MASK_STALE_FRAMES   ACH_MASK_EAGAIN
#define	ACH_MASK_LOCKED   ACH_MASK_EAGAIN
#define	ACH_CHAN_NAME_MAX   64ul
	maximum size of a channel name

Typedefs
typedef enum ach_status	ach_status_t
	return status codes for ach functions. More...
typedef enum ach_mask	ach_mask_t
	Convenience typedef for enum ach_mask.
typedef struct achk_opt	achk_opt_t
	Struct containing 'cache' of kernel module data to avoid updating when no changes exist. More...

Enumerations
enum	ach_status {   ACH_OK = 0, ACH_OVERFLOW = 1, ACH_INVALID_NAME = 2, ACH_BAD_SHM_FILE = 3,   ACH_FAILED_SYSCALL = 4, ACH_EAGAIN = 5, ACH_MISSED_FRAME = 6, ACH_TIMEOUT = 7,   ACH_EEXIST = 8, ACH_ENOENT = 9, ACH_CLOSED = 10, ACH_BUG = 11,   ACH_EINVAL = 12, ACH_CORRUPT = 13, ACH_BAD_HEADER = 14, ACH_EACCES = 15,   ACH_CANCELED = 16, ACH_EFAULT = 17, ACH_EINTR = 18, ACH_ENOTSUP = 19 }
	return status codes for ach functions. More...
enum	ach_mask {   ACH_MASK_OK = ACH_STATUS_MASK(ACH_OK), ACH_MASK_OVERFLOW = ACH_STATUS_MASK(ACH_OVERFLOW), ACH_MASK_INVALID_NAME = ACH_STATUS_MASK(ACH_INVALID_NAME), ACH_MASK_BAD_SHM_FILE = ACH_STATUS_MASK(ACH_BAD_SHM_FILE),   ACH_MASK_FAILED_SYSCALL = ACH_STATUS_MASK(ACH_FAILED_SYSCALL), ACH_MASK_EAGAIN = ACH_STATUS_MASK(ACH_EAGAIN), ACH_MASK_MISSED_FRAME = ACH_STATUS_MASK(ACH_MISSED_FRAME), ACH_MASK_TIMEOUT = ACH_STATUS_MASK(ACH_TIMEOUT),   ACH_MASK_EEXIST = ACH_STATUS_MASK(ACH_EEXIST), ACH_MASK_ENOENT = ACH_STATUS_MASK(ACH_ENOENT), ACH_MASK_CLOSED = ACH_STATUS_MASK(ACH_CLOSED), ACH_MASK_BUG = ACH_STATUS_MASK(ACH_BUG),   ACH_MASK_EINVAL = ACH_STATUS_MASK(ACH_EINVAL), ACH_MASK_CORRUPT = ACH_STATUS_MASK(ACH_CORRUPT), ACH_MASK_BAD_HEADER = ACH_STATUS_MASK(ACH_BAD_HEADER), ACH_MASK_EACCES = ACH_STATUS_MASK(ACH_EACCES),   ACH_MASK_CANCELED = ACH_STATUS_MASK(ACH_CANCELED), ACH_MASK_EFAULT = ACH_STATUS_MASK(ACH_EFAULT), ACH_MASK_EINTR = ACH_STATUS_MASK(ACH_EINTR), ACH_MASK_ENOTSUP = ACH_STATUS_MASK(ACH_ENOTSUP),   ACH_MASK_LOCKED = ACH_STATUS_MASK(ACH_LOCKED), ACH_MASK_NONE = 0, ACH_MASK_ALL = 0xffffffff }
	Bit masks that correspond to members of enum ach_status. More...
enum	ach_get_opts_t {   ACH_O_NONBLOCK = 0x00, ACH_O_FIRST = 0x00, ACH_O_ABSTIME = 0x00, ACH_O_WAIT = 0x01,   ACH_O_LAST = 0x02, ACH_O_COPY = 0x04, ACH_O_RELTIME = 0x08 }
	Option flags for ach_get(). More...

Functions
enum ach_status	ach_get_fun (void *cx, void **obj_dst, const void *chan_src, size_t frame_size)
	Function type to transfer data out of the channel. More...
enum ach_status	ach_put_fun (void *cx, void *chan_dst, const void *obj_src)
	Function type to transfer data into the channel. More...

Detailed Description

This file contains declarations needed by both the userspace public interface and the Linux kernel implementation.

Author

Neil T. Dantam

Macro Definition Documentation

#define ACH_STATUS_MASK

(

r

)

(1<<(r))

Generate a bit mask from an ach status type.

See also

enum ach_mask

Typedef Documentation

typedef enum ach_status ach_status_t

return status codes for ach functions.

See also

enum ach_mask

typedef struct achk_opt achk_opt_t

Struct containing 'cache' of kernel module data to avoid updating when no changes exist.

Enumeration Type Documentation

enum ach_get_opts_t

Option flags for ach_get().

Default behavior is to retrieve the oldest unseen frame without waiting.

Enumerator
ACH_O_NONBLOCK	Do not block for a new messages. Exclusive with ACH_O_WAIT.
ACH_O_FIRST	Retrieve the oldest unseen message. Exclusive with ACH_O_LAST.
ACH_O_ABSTIME	Timeout is an absolute time. Timeout must use the clock set during channel creation. Exclusive with ACH_O_RELTIME. See also ach_channel_clock()
ACH_O_WAIT	Block until an unseen message arrives or timeout. If the channel already has data that this subscriber has not seen, ach_get() immediately copies the new data. Otherwise, it waits for some other process or thread to put data into the channel. Exclusive with ACH_O_NONBLOCK.
ACH_O_LAST	Read the newest message out of the channel. If the channel contains multiple messages that this subscriber has not seen, ach_get() will return the newest of these messages. The subscriber will skip past all older messages. Exclusive with ACH_O_FIRST.
ACH_O_COPY	Copy the message out of the channel, even if already seen. The return code of ach_get() for successful copy is ACH_OK.
ACH_O_RELTIME	Timeout is a relative time. Exclusive with ACH_O_ABSTIME.

enum ach_mask

Bit masks that correspond to members of enum ach_status.

These masks are useful to check whether a status code matches a set of values.

enum ach_status

return status codes for ach functions.

See also

enum ach_mask

Enumerator
ACH_OK	Call successful.
ACH_OVERFLOW	destination too small to hold frame
ACH_INVALID_NAME	invalid channel name
ACH_BAD_SHM_FILE	channel file didn't look right
ACH_FAILED_SYSCALL	a system call failed
ACH_EAGAIN	no new data in the channel
ACH_MISSED_FRAME	we missed the next frame
ACH_TIMEOUT	timeout before frame received
ACH_EEXIST	channel file already exists
ACH_ENOENT	channel file doesn't exist
ACH_CLOSED	unused
ACH_BUG	internal ach error
ACH_EINVAL	invalid parameter
ACH_CORRUPT	channel memory has been corrupted
ACH_BAD_HEADER	an invalid header was given
ACH_EACCES	permission denied
ACH_CANCELED	operation canceled
ACH_EFAULT	bad address for data copy
ACH_EINTR	operation interrupted. Only used internally and not returned to library callers.
ACH_ENOTSUP	not supported.

Function Documentation

enum ach_status ach_get_fun	(	void *	cx,
		void **	obj_dst,
		const void *	chan_src,
		size_t	frame_size
	)

Function type to transfer data out of the channel.

This function could, for example, perform tasks such as de-serialization and memory allocation.

Returns

0 on success, nonzero on failure

enum ach_status ach_put_fun	(	void *	cx,
		void *	chan_dst,
		const void *	obj_src
	)

Function type to transfer data into the channel.

This function could, for example, perform tasks such as serialization.

Returns

0 on success, nonzero on failure