#ifndef EIO_H_
#define EIO_H_
#include <stddef.h>
#include <sys/types.h>
typedef struct eio_req eio_req;
typedef int (*eio_cb)(eio_req *req);
#ifndef EIO_REQ_MEMBERS
# define EIO_REQ_MEMBERS
#endif
#ifndef EIO_STRUCT_STAT
# define EIO_STRUCT_STAT struct stat
#endif
enum {
EIO_QUIT,
EIO_OPEN, EIO_CLOSE, EIO_DUP2,
EIO_READ, EIO_WRITE,
EIO_READAHEAD, EIO_SENDFILE,
EIO_STAT, EIO_LSTAT, EIO_FSTAT,
EIO_TRUNCATE, EIO_FTRUNCATE,
EIO_UTIME, EIO_FUTIME,
EIO_CHMOD, EIO_FCHMOD,
EIO_CHOWN, EIO_FCHOWN,
EIO_SYNC, EIO_FSYNC, EIO_FDATASYNC,
EIO_UNLINK, EIO_RMDIR, EIO_MKDIR, EIO_RENAME,
EIO_MKNOD, EIO_READDIR,
EIO_LINK, EIO_SYMLINK, EIO_READLINK,
EIO_GROUP, EIO_NOP,
EIO_BUSY,
};
typedef double eio_tstamp; /* feel free to use double in your code directly */
/* eio request structure */
/* this structure is mostly read-only */
struct eio_req
{
eio_req volatile *next; /* private */
ssize_t result; /* result of syscall, e.g. result = read (... */
off_t offs; /* read, write, truncate, readahead: file offset; mknod: dev_t */
size_t size; /* read, write, readahead, sendfile: length */
void *ptr1; /* all applicable requests: pathname, old name */
void *ptr2; /* all applicable requests: new name or memory buffer */
eio_tstamp nv1; /* utime, futime: atime; busy: sleep time */
eio_tstamp nv2; /* utime, futime: mtime */
int type; /* EIO_xxx constant */
int int1; /* all applicable requests: file descriptor; sendfile: output fd; open: flags */
long int2; /* chown, fchown: uid; sendfile: input fd; open, chmod, mkdir, mknod: file mode */
long int3; /* chown, fchown: gid */
int errorno; /* errno value on syscall return */
unsigned char flags; /* private */
signed char pri; /* the priority */
void *data;
eio_cb finish;
void (*destroy)(eio_req *req); /* called when requets no longer needed */
void (*feed)(eio_req *req); /* only used for group requests */
EIO_REQ_MEMBERS
eio_req *grp, *grp_prev, *grp_next, *grp_first; /* private */
};
enum {
EIO_FLAG_CANCELLED = 0x01, /* request was cancelled */
EIO_FLAG_PTR1_FREE = 0x02, /* need to free(ptr1) */
EIO_FLAG_PTR2_FREE = 0x04 /* need to free(ptr2) */
};
enum {
EIO_PRI_MIN = -4,
EIO_PRI_MAX = 4,
EIO_PRI_DEFAULT = 0,
EIO_PRI_BIAS = -EIO_PRI_MIN,
EIO_NUM_PRI = EIO_PRI_MAX + EIO_PRI_BIAS + 1
};
/* returns < 0 on error, errno set
* need_poll, if non-zero, will be called when results are available
* and eio_poll_cb needs to be invoked (it MUST NOT call eio_poll_cb itself).
* done_poll is called when the need to poll is gone.
*/
int eio_init (void (*want_poll)(void), void (*done_poll)(void));
/* must be called regularly to handle pending requests */
/* returns 0 if all requests were handled, -1 if not, or the value of EIO_FINISH if != 0 */
int eio_poll (void);
/* stop polling if poll took longer than duration seconds */
void eio_set_max_poll_time (eio_tstamp nseconds);
/* do not handle more then count requests in one call to eio_poll_cb */
void eio_set_max_poll_reqs (unsigned int nreqs);
/* set minimum required number
* maximum wanted number
* or maximum idle number of threads */
void eio_set_min_parallel (unsigned int nthreads);
void eio_set_max_parallel (unsigned int nthreads);
void eio_set_max_idle (unsigned int nthreads);
unsigned int eio_nreqs (void); /* number of requests in-flight */
unsigned int eio_nready (void); /* number of not-yet handled requests */
unsigned int eio_npending (void); /* numbe rof finished but unhandled requests */
unsigned int eio_nthreads (void); /* number of worker threads in use currently */
/*****************************************************************************/
/* high-level request API */
#ifndef EIO_NO_WRAPPERS
eio_req *eio_nop (int pri, eio_cb cb, void *data); /* does nothing except go through the whole process */
eio_req *eio_busy (eio_tstamp delay, int pri, eio_cb cb, void *data); /* ties a thread for this long, simulating busyness */
eio_req *eio_sync (int pri, eio_cb cb, void *data);
eio_req *eio_fsync (int fd, int pri, eio_cb cb, void *data);
eio_req *eio_fdatasync (int fd, int pri, eio_cb cb, void *data);
eio_req *eio_close (int fd, int pri, eio_cb cb, void *data);
eio_req *eio_readahead (int fd, off_t offset, size_t length, int pri, eio_cb cb, void *data);
eio_req *eio_read (int fd, void *buf, size_t length, off_t offset, int pri, eio_cb cb, void *data);
eio_req *eio_write (int fd, void *buf, size_t length, off_t offset, int pri, eio_cb cb, void *data);
eio_req *eio_fstat (int fd, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
eio_req *eio_futime (int fd, eio_tstamp atime, eio_tstamp mtime, int pri, eio_cb cb, void *data);
eio_req *eio_ftruncate (int fd, off_t offset, int pri, eio_cb cb, void *data);
eio_req *eio_fchmod (int fd, mode_t mode, int pri, eio_cb cb, void *data);
eio_req *eio_fchown (int fd, uid_t uid, gid_t gid, int pri, eio_cb cb, void *data);
eio_req *eio_dup2 (int fd, int fd2, int pri, eio_cb cb, void *data);
eio_req *eio_sendfile (int out_fd, int in_fd, off_t in_offset, size_t length, int pri, eio_cb cb, void *data);
eio_req *eio_open (const char *path, int flags, mode_t mode, int pri, eio_cb cb, void *data);
eio_req *eio_utime (const char *path, eio_tstamp atime, eio_tstamp mtime, int pri, eio_cb cb, void *data);
eio_req *eio_truncate (const char *path, off_t offset, int pri, eio_cb cb, void *data);
eio_req *eio_chown (const char *path, uid_t uid, gid_t gid, int pri, eio_cb cb, void *data);
eio_req *eio_chmod (const char *path, mode_t mode, int pri, eio_cb cb, void *data);
eio_req *eio_mkdir (const char *path, mode_t mode, int pri, eio_cb cb, void *data);
eio_req *eio_readdir (const char *path, int pri, eio_cb cb, void *data); /* result=ptr2 allocated dynamically */
eio_req *eio_rmdir (const char *path, int pri, eio_cb cb, void *data);
eio_req *eio_unlink (const char *path, int pri, eio_cb cb, void *data);
eio_req *eio_readlink (const char *path, int pri, eio_cb cb, void *data); /* result=ptr2 allocated dynamically */
eio_req *eio_stat (const char *path, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
eio_req *eio_lstat (const char *path, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
eio_req *eio_mknod (const char *path, mode_t mode, dev_t dev, int pri, eio_cb cb, void *data);
eio_req *eio_link (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
eio_req *eio_symlink (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
eio_req *eio_rename (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
#endif
/* for groups */
eio_req *eio_grp (eio_cb cb, void *data);
void eio_grp_feed (eio_req *grp, void (*feed)(eio_req *req), int limit);
void eio_grp_limit (eio_req *grp, int limit);
void eio_grp_add (eio_req *grp, eio_req *req);
void eio_grp_cancel (eio_req *grp); /* cancels all sub requests but not the group */
/* cancel a request as soon fast as possible */
void eio_cancel (eio_req *req);
/* destroy a request that has never been submitted */
void eio_destroy (eio_req *req);
/* true if the request was cancelled, useful in the invoke callback */
#define EIO_CANCELLED(req) ((req)->flags & EIO_FLAG_CANCELLED)
#define EIO_RESULT(req) ((req)->result)
/* returns a pointer to the result buffer allocated by eio */
#define EIO_BUF(req) ((req)->ptr2)
#define EIO_STAT_BUF(req) ((EIO_STRUCT_STAT *)EIO_BUF(req))
#define EIO_PATH(req) ((char *)(req)->ptr1)
/*****************************************************************************/
/* low-level request API */
/* must be used to initialise eio_req's */
#define EIO_INIT(req,prio,finish_cb, destroy_cb) \
memset ((req), 0, sizeof (eio_req)); \
(req)->pri = (prio) + EIO_PRI_BIAS; \
(req)->finish = (finish_cb); \
(req)->destroy = (destroy_cb)
/* submit a request for execution */
void eio_submit (eio_req *req);
/*****************************************************************************/
/* convinience functions */
ssize_t eio_sendfile_sync (int ofd, int ifd, off_t offset, size_t count);
#endif