1 /*
2  * libeio API header
3  *
4  * Copyright (c) 2007,2008,2009,2010,2011 Marc Alexander Lehmann <libeio@schmorp.de>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without modifica-
8  * tion, are permitted provided that the following conditions are met:
9  *
10  *   1.  Redistributions of source code must retain the above copyright notice,
11  *       this list of conditions and the following disclaimer.
12  *
13  *   2.  Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in the
15  *       documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19  * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
20  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21  * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25  * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26  * OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  * Alternatively, the contents of this file may be used under the terms of
29  * the GNU General Public License ("GPL") version 2 or any later version,
30  * in which case the provisions of the GPL are applicable instead of
31  * the above. If you wish to allow the use of your version of this file
32  * only under the terms of the GPL and not to allow others to use your
33  * version of this file under the BSD license, indicate your decision
34  * by deleting the provisions above and replace them with the notice
35  * and other provisions required by the GPL. If you do not delete the
36  * provisions above, a recipient may use your version of this file under
37  * either the BSD or the GPL.
38  */
39 
40 #ifndef EIO_H_
41 #define EIO_H_
42 
43 #ifdef __cplusplus
44 extern "C" {
45 #endif
46 
47 #include <stddef.h>
48 #include <signal.h>
49 #include <sys/types.h>
50 #include "stdio.h"
51 
52 typedef struct eio_req    eio_req;
53 typedef struct eio_dirent eio_dirent;
54 
55 typedef int (*eio_cb)(eio_req *req);
56 
57 #ifndef EIO_REQ_MEMBERS
58 # define EIO_REQ_MEMBERS
59 #endif
60 
61 #ifndef EIO_STRUCT_STAT
62 # ifdef _WIN32
63 #  define EIO_STRUCT_STAT struct _stati64
64 #  define EIO_STRUCT_STATI64
65 # else
66 #  define EIO_STRUCT_STAT struct stat
67 # endif
68 #endif
69 
70 #ifdef _WIN32
71   typedef int      eio_uid_t;
72   typedef int      eio_gid_t;
73   #ifdef __MINGW32__ /* no intptr_t */
74     typedef ssize_t  eio_ssize_t;
75   #else
76     typedef intptr_t eio_ssize_t; /* or SSIZE_T */
77   #endif
78   #if __GNUC__
79     typedef long long eio_ino_t; /* signed for compatibility to msvc */
80   #else
81     typedef __int64   eio_ino_t; /* unsigned not supported by msvc */
82   #endif
83 #else
84   typedef uid_t    eio_uid_t;
85   typedef gid_t    eio_gid_t;
86   typedef ssize_t  eio_ssize_t;
87   typedef ino_t    eio_ino_t;
88 #endif
89 
90 #ifndef EIO_STRUCT_STATVFS
91 # define EIO_STRUCT_STATVFS struct statvfs
92 #endif
93 
94 /* managing working directories */
95 
96 typedef struct eio_pwd *eio_wd;
97 
98 #define EIO_CWD 0 /* the current working directory of the process, guaranteed to be a null pointer */
99 #define EIO_INVALID_WD ((eio_wd)(int)-1) /* failure return for eio_wd_open */
100 
101 eio_wd eio_wd_open_sync (eio_wd wd, const char *path);
102 void eio_wd_close_sync (eio_wd wd);
103 
104 /* for readdir */
105 
106 /* eio_readdir flags */
107 enum
108 {
109   EIO_READDIR_DENTS         = 0x01, /* ptr2 contains eio_dirents, not just the (unsorted) names */
110   EIO_READDIR_DIRS_FIRST    = 0x02, /* dirents gets sorted into a good stat() ing order to find directories first */
111   EIO_READDIR_STAT_ORDER    = 0x04, /* dirents gets sorted into a good stat() ing order to quickly stat all files */
112   EIO_READDIR_FOUND_UNKNOWN = 0x80, /* set by eio_readdir when *_ARRAY was set and any TYPE=UNKNOWN's were found */
113 
114   EIO_READDIR_CUSTOM1       = 0x100, /* for use by apps */
115   EIO_READDIR_CUSTOM2       = 0x200  /* for use by apps */
116 };
117 
118 /* using "typical" values in the hope that the compiler will do something sensible */
119 enum eio_dtype
120 {
121   EIO_DT_UNKNOWN =  0,
122   EIO_DT_FIFO    =  1,
123   EIO_DT_CHR     =  2,
124   EIO_DT_MPC     =  3, /* multiplexed char device (v7+coherent) */
125   EIO_DT_DIR     =  4,
126   EIO_DT_NAM     =  5, /* xenix special named file */
127   EIO_DT_BLK     =  6,
128   EIO_DT_MPB     =  7, /* multiplexed block device (v7+coherent) */
129   EIO_DT_REG     =  8,
130   EIO_DT_NWK     =  9, /* HP-UX network special */
131   EIO_DT_CMP     =  9, /* VxFS compressed */
132   EIO_DT_LNK     = 10,
133   /*  DT_SHAD    = 11,*/
134   EIO_DT_SOCK    = 12,
135   EIO_DT_DOOR    = 13, /* solaris door */
136   EIO_DT_WHT     = 14,
137   EIO_DT_MAX     = 15  /* highest DT_VALUE ever, hopefully */
138 };
139 
140 struct eio_dirent
141 {
142   int nameofs; /* offset of null-terminated name string in (char *)req->ptr2 */
143   unsigned short namelen; /* size of filename without trailing 0 */
144   unsigned char type; /* one of EIO_DT_* */
145   signed char score; /* internal use */
146   eio_ino_t inode; /* the inode number, if available, otherwise unspecified */
147 };
148 
149 /* eio_msync flags */
150 enum
151 {
152   EIO_MS_ASYNC      = 1,
153   EIO_MS_INVALIDATE = 2,
154   EIO_MS_SYNC       = 4
155 };
156 
157 /* eio_mtouch flags */
158 enum
159 {
160   EIO_MT_MODIFY     = 1
161 };
162 
163 /* eio_sync_file_range flags */
164 enum
165 {
166   EIO_SYNC_FILE_RANGE_WAIT_BEFORE = 1,
167   EIO_SYNC_FILE_RANGE_WRITE       = 2,
168   EIO_SYNC_FILE_RANGE_WAIT_AFTER  = 4
169 };
170 
171 /* eio_fallocate flags */
172 enum
173 {
174   EIO_FALLOC_FL_KEEP_SIZE = 1 /* MUST match the value in linux/falloc.h */
175 };
176 
177 /* timestamps and differences - feel free to use double in your code directly */
178 typedef double eio_tstamp;
179 
180 /* the eio request structure */
181 enum
182 {
183   EIO_CUSTOM,
184   EIO_WD_OPEN, EIO_WD_CLOSE,
185 
186   EIO_CLOSE, EIO_DUP2,
187   EIO_READ, EIO_WRITE,
188   EIO_READAHEAD, EIO_SENDFILE,
189   EIO_FSTAT, EIO_FSTATVFS,
190   EIO_FTRUNCATE, EIO_FUTIME, EIO_FCHMOD, EIO_FCHOWN,
191   EIO_SYNC, EIO_FSYNC, EIO_FDATASYNC, EIO_SYNCFS,
192   EIO_MSYNC, EIO_MTOUCH, EIO_SYNC_FILE_RANGE, EIO_FALLOCATE,
193   EIO_MLOCK, EIO_MLOCKALL,
194   EIO_GROUP, EIO_NOP,
195   EIO_BUSY,
196 
197   /* these use wd + ptr1, but are emulated */
198   EIO_REALPATH,
199   EIO_STATVFS,
200   EIO_READDIR,
201 
202   /* all the following requests use wd + ptr1 as path in xxxat functions */
203   EIO_OPEN,
204   EIO_STAT, EIO_LSTAT,
205   EIO_TRUNCATE,
206   EIO_UTIME,
207   EIO_CHMOD,
208   EIO_CHOWN,
209   EIO_UNLINK, EIO_RMDIR, EIO_MKDIR, EIO_RENAME,
210   EIO_MKNOD,
211   EIO_LINK, EIO_SYMLINK, EIO_READLINK,
212 
213   EIO_REQ_TYPE_NUM
214 };
215 
216 /* mlockall constants */
217 enum
218 {
219   EIO_MCL_CURRENT = 1,
220   EIO_MCL_FUTURE  = 2,
221 };
222 
223 /* request priorities */
224 
225 enum {
226   EIO_PRI_MIN     = -4,
227   EIO_PRI_MAX     =  4,
228   EIO_PRI_DEFAULT =  0,
229 };
230 
231 /* eio request structure */
232 /* this structure is mostly read-only */
233 /* when initialising it, all members must be zero-initialised */
234 struct eio_req
235 {
236   eio_req volatile *next; /* private ETP */
237 
238   eio_wd wd;       /* all applicable requests: working directory of pathname, old name; wd_open: return wd */
239 
240   eio_ssize_t result;  /* result of syscall, e.g. result = read (... */
241   off_t offs;      /* read, write, truncate, readahead, sync_file_range, fallocate: file offset, mknod: dev_t */
242   size_t size;     /* read, write, readahead, sendfile, msync, mlock, sync_file_range, fallocate: length */
243   void *ptr1;      /* all applicable requests: pathname, old name; readdir: optional eio_dirents */
244   void *ptr2;      /* all applicable requests: new name or memory buffer; readdir: name strings */
245   eio_tstamp nv1;  /* utime, futime: atime; busy: sleep time */
246   eio_tstamp nv2;  /* utime, futime: mtime */
247 
248   int type;        /* EIO_xxx constant ETP */
249   int int1;        /* all applicable requests: file descriptor; sendfile: output fd; open, msync, mlockall, readdir: flags */
250   long int2;       /* chown, fchown: uid; sendfile: input fd; open, chmod, mkdir, mknod: file mode, sync_file_range, fallocate: flags */
251   long int3;       /* chown, fchown: gid; rename, link: working directory of new name */
252   int errorno;     /* errno value on syscall return */
253 
254 #if __i386 || __amd64
255   unsigned char cancelled;
256 #else
257   sig_atomic_t cancelled;
258 #endif
259 
260   unsigned char flags; /* private */
261   signed char pri;     /* the priority */
262 
263   void *data;
264   eio_cb finish;
265   void (*destroy)(eio_req *req); /* called when request no longer needed */
266   void (*feed)(eio_req *req);    /* only used for group requests */
267 
268   EIO_REQ_MEMBERS
269 
270   eio_req *grp, *grp_prev, *grp_next, *grp_first; /* private */
271 };
272 
273 /* _private_ request flags */
274 enum {
275   EIO_FLAG_PTR1_FREE = 0x01, /* need to free(ptr1) */
276   EIO_FLAG_PTR2_FREE = 0x02, /* need to free(ptr2) */
277   EIO_FLAG_GROUPADD  = 0x04  /* some request was added to the group */
278 };
279 
280 /* undocumented/unsupported/private helper */
281 /*void eio_page_align (void **addr, size_t *length);*/
282 
283 /* returns < 0 on error, errno set
284  * need_poll, if non-zero, will be called when results are available
285  * and eio_poll_cb needs to be invoked (it MUST NOT call eio_poll_cb itself).
286  * done_poll is called when the need to poll is gone.
287  */
288 int eio_init (void (*want_poll)(void), void (*done_poll)(void));
289 
290 /* must be called regularly to handle pending requests */
291 /* returns 0 if all requests were handled, -1 if not, or the value of EIO_FINISH if != 0 */
292 int eio_poll (void);
293 
294 /* stop polling if poll took longer than duration seconds */
295 void eio_set_max_poll_time (eio_tstamp nseconds);
296 /* do not handle more then count requests in one call to eio_poll_cb */
297 void eio_set_max_poll_reqs (unsigned int nreqs);
298 
299 /* set minimum required number
300  * maximum wanted number
301  * or maximum idle number of threads */
302 void eio_set_min_parallel (unsigned int nthreads);
303 void eio_set_max_parallel (unsigned int nthreads);
304 void eio_set_max_idle     (unsigned int nthreads);
305 void eio_set_idle_timeout (unsigned int seconds);
306 
307 unsigned int eio_nreqs    (void); /* number of requests in-flight */
308 unsigned int eio_nready   (void); /* number of not-yet handled requests */
309 unsigned int eio_npending (void); /* number of finished but unhandled requests */
310 unsigned int eio_nthreads (void); /* number of worker threads in use currently */
311 
312 /*****************************************************************************/
313 /* convenience wrappers */
314 
315 #ifndef EIO_NO_WRAPPERS
316 eio_req *eio_wd_open   (const char *path, int pri, eio_cb cb, void *data); /* result=wd */
317 eio_req *eio_wd_close  (eio_wd wd, int pri, eio_cb cb, void *data);
318 eio_req *eio_nop       (int pri, eio_cb cb, void *data); /* does nothing except go through the whole process */
319 eio_req *eio_busy      (eio_tstamp delay, int pri, eio_cb cb, void *data); /* ties a thread for this long, simulating busyness */
320 eio_req *eio_sync      (int pri, eio_cb cb, void *data);
321 eio_req *eio_fsync     (int fd, int pri, eio_cb cb, void *data);
322 eio_req *eio_fdatasync (int fd, int pri, eio_cb cb, void *data);
323 eio_req *eio_syncfs    (int fd, int pri, eio_cb cb, void *data);
324 eio_req *eio_msync     (void *addr, size_t length, int flags, int pri, eio_cb cb, void *data);
325 eio_req *eio_mtouch    (void *addr, size_t length, int flags, int pri, eio_cb cb, void *data);
326 eio_req *eio_mlock     (void *addr, size_t length, int pri, eio_cb cb, void *data);
327 eio_req *eio_mlockall  (int flags, int pri, eio_cb cb, void *data);
328 eio_req *eio_sync_file_range (int fd, off_t offset, size_t nbytes, unsigned int flags, int pri, eio_cb cb, void *data);
329 eio_req *eio_fallocate (int fd, int mode, off_t offset, size_t len, int pri, eio_cb cb, void *data);
330 eio_req *eio_close     (int fd, int pri, eio_cb cb, void *data);
331 eio_req *eio_readahead (int fd, off_t offset, size_t length, int pri, eio_cb cb, void *data);
332 eio_req *eio_read      (int fd, void *buf, size_t length, off_t offset, int pri, eio_cb cb, void *data);
333 eio_req *eio_write     (int fd, void *buf, size_t length, off_t offset, int pri, eio_cb cb, void *data);
334 eio_req *eio_fstat     (int fd, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
335 eio_req *eio_fstatvfs  (int fd, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
336 eio_req *eio_futime    (int fd, eio_tstamp atime, eio_tstamp mtime, int pri, eio_cb cb, void *data);
337 eio_req *eio_ftruncate (int fd, off_t offset, int pri, eio_cb cb, void *data);
338 eio_req *eio_fchmod    (int fd, mode_t mode, int pri, eio_cb cb, void *data);
339 eio_req *eio_fchown    (int fd, eio_uid_t uid, eio_gid_t gid, int pri, eio_cb cb, void *data);
340 eio_req *eio_dup2      (int fd, int fd2, int pri, eio_cb cb, void *data);
341 eio_req *eio_sendfile  (int out_fd, int in_fd, off_t in_offset, size_t length, int pri, eio_cb cb, void *data);
342 eio_req *eio_open      (const char *path, int flags, mode_t mode, int pri, eio_cb cb, void *data);
343 eio_req *eio_utime     (const char *path, eio_tstamp atime, eio_tstamp mtime, int pri, eio_cb cb, void *data);
344 eio_req *eio_truncate  (const char *path, off_t offset, int pri, eio_cb cb, void *data);
345 eio_req *eio_chown     (const char *path, eio_uid_t uid, eio_gid_t gid, int pri, eio_cb cb, void *data);
346 eio_req *eio_chmod     (const char *path, mode_t mode, int pri, eio_cb cb, void *data);
347 eio_req *eio_mkdir     (const char *path, mode_t mode, int pri, eio_cb cb, void *data);
348 eio_req *eio_readdir   (const char *path, int flags, int pri, eio_cb cb, void *data); /* result=ptr2 allocated dynamically */
349 eio_req *eio_rmdir     (const char *path, int pri, eio_cb cb, void *data);
350 eio_req *eio_unlink    (const char *path, int pri, eio_cb cb, void *data);
351 eio_req *eio_readlink  (const char *path, int pri, eio_cb cb, void *data); /* result=ptr2 allocated dynamically */
352 eio_req *eio_realpath  (const char *path, int pri, eio_cb cb, void *data); /* result=ptr2 allocated dynamically */
353 eio_req *eio_stat      (const char *path, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
354 eio_req *eio_lstat     (const char *path, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
355 eio_req *eio_statvfs   (const char *path, int pri, eio_cb cb, void *data); /* stat buffer=ptr2 allocated dynamically */
356 eio_req *eio_mknod     (const char *path, mode_t mode, dev_t dev, int pri, eio_cb cb, void *data);
357 eio_req *eio_link      (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
358 eio_req *eio_symlink   (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
359 eio_req *eio_rename    (const char *path, const char *new_path, int pri, eio_cb cb, void *data);
360 eio_req *eio_custom    (void (*execute)(eio_req *), int pri, eio_cb cb, void *data);
361 #endif
362 
363 /*****************************************************************************/
364 /* groups */
365 
366 eio_req *eio_grp       (eio_cb cb, void *data);
367 void eio_grp_feed      (eio_req *grp, void (*feed)(eio_req *req), int limit);
368 void eio_grp_limit     (eio_req *grp, int limit);
369 void eio_grp_add       (eio_req *grp, eio_req *req);
370 void eio_grp_cancel    (eio_req *grp); /* cancels all sub requests but not the group */
371 
372 /*****************************************************************************/
373 /* request api */
374 
375 /* true if the request was cancelled, useful in the invoke callback */
376 #define EIO_CANCELLED(req)   ((req)->cancelled)
377 
378 #define EIO_RESULT(req)      ((req)->result)
379 /* returns a pointer to the result buffer allocated by eio */
380 #define EIO_BUF(req)         ((req)->ptr2)
381 #define EIO_STAT_BUF(req)    ((EIO_STRUCT_STAT    *)EIO_BUF(req))
382 #define EIO_STATVFS_BUF(req) ((EIO_STRUCT_STATVFS *)EIO_BUF(req))
383 #define EIO_PATH(req)        ((char *)(req)->ptr1)
384 
385 /* submit a request for execution */
386 void eio_submit (eio_req *req);
387 /* cancel a request as soon fast as possible, if possible */
388 void eio_cancel (eio_req *req);
389 
390 /*****************************************************************************/
391 /* convenience functions */
392 
393 eio_ssize_t eio_sendfile_sync (int ofd, int ifd, off_t offset, size_t count);
394 
395 #ifdef __cplusplus
396 }
397 #endif
398 
399 #endif
400 
401