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apr_file_io.h
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16 
17 #ifndef APR_FILE_IO_H
18 #define APR_FILE_IO_H
19 
20 /**
21  * @file apr_file_io.h
22  * @brief APR File I/O Handling
23  */
24 
25 #include "apr.h"
26 #include "apr_pools.h"
27 #include "apr_time.h"
28 #include "apr_errno.h"
29 #include "apr_file_info.h"
30 #include "apr_inherit.h"
31 
32 #define APR_WANT_STDIO /**< for SEEK_* */
33 #define APR_WANT_IOVEC /**< for apr_file_writev */
34 #include "apr_want.h"
35 
36 #ifdef __cplusplus
37 extern "C" {
38 #endif /* __cplusplus */
39 
40 /**
41  * @defgroup apr_file_io File I/O Handling Functions
42  * @ingroup APR
43  * @{
44  */
45 
46 /**
47  * @defgroup apr_file_open_flags File Open Flags/Routines
48  * @{
49  */
50 
51 /* Note to implementors: Values in the range 0x00100000--0x80000000
52  are reserved for platform-specific values. */
53 
54 #define APR_FOPEN_READ 0x00001 /**< Open the file for reading */
55 #define APR_FOPEN_WRITE 0x00002 /**< Open the file for writing */
56 #define APR_FOPEN_CREATE 0x00004 /**< Create the file if not there */
57 #define APR_FOPEN_APPEND 0x00008 /**< Append to the end of the file */
58 #define APR_FOPEN_TRUNCATE 0x00010 /**< Open the file and truncate
59  to 0 length */
60 #define APR_FOPEN_BINARY 0x00020 /**< Open the file in binary mode
61  (This flag is ignored on UNIX
62  because it has no meaning)*/
63 #define APR_FOPEN_EXCL 0x00040 /**< Open should fail if #APR_FOPEN_CREATE
64  and file exists. */
65 #define APR_FOPEN_BUFFERED 0x00080 /**< Open the file for buffered I/O */
66 #define APR_FOPEN_DELONCLOSE 0x00100 /**< Delete the file after close */
67 #define APR_FOPEN_XTHREAD 0x00200 /**< Platform dependent tag to open
68  the file for use across multiple
69  threads */
70 #define APR_FOPEN_SHARELOCK 0x00400 /**< Platform dependent support for
71  higher level locked read/write
72  access to support writes across
73  process/machines */
74 #define APR_FOPEN_NOCLEANUP 0x00800 /**< Do not register a cleanup
75  when the file is opened. The
76  apr_os_file_t handle in apr_file_t
77  will not be closed when the pool
78  is destroyed. */
79 #define APR_FOPEN_SENDFILE_ENABLED 0x01000 /**< Advisory flag that this
80  file should support
81  apr_socket_sendfile operation */
82 #define APR_FOPEN_LARGEFILE 0x04000 /**< Platform dependent flag to enable
83  * large file support, see WARNING below
84  */
85 #define APR_FOPEN_SPARSE 0x08000 /**< Platform dependent flag to enable
86  * sparse file support, see WARNING below
87  */
88 #define APR_FOPEN_NONBLOCK 0x40000 /**< Platform dependent flag to enable
89  * non blocking file io */
90 
91 
92 /* backcompat */
93 #define APR_READ APR_FOPEN_READ /**< @deprecated @see APR_FOPEN_READ */
94 #define APR_WRITE APR_FOPEN_WRITE /**< @deprecated @see APR_FOPEN_WRITE */
95 #define APR_CREATE APR_FOPEN_CREATE /**< @deprecated @see APR_FOPEN_CREATE */
96 #define APR_APPEND APR_FOPEN_APPEND /**< @deprecated @see APR_FOPEN_APPEND */
97 #define APR_TRUNCATE APR_FOPEN_TRUNCATE /**< @deprecated @see APR_FOPEN_TRUNCATE */
98 #define APR_BINARY APR_FOPEN_BINARY /**< @deprecated @see APR_FOPEN_BINARY */
99 #define APR_EXCL APR_FOPEN_EXCL /**< @deprecated @see APR_FOPEN_EXCL */
100 #define APR_BUFFERED APR_FOPEN_BUFFERED /**< @deprecated @see APR_FOPEN_BUFFERED */
101 #define APR_DELONCLOSE APR_FOPEN_DELONCLOSE /**< @deprecated @see APR_FOPEN_DELONCLOSE */
102 #define APR_XTHREAD APR_FOPEN_XTHREAD /**< @deprecated @see APR_FOPEN_XTHREAD */
103 #define APR_SHARELOCK APR_FOPEN_SHARELOCK /**< @deprecated @see APR_FOPEN_SHARELOCK */
104 #define APR_FILE_NOCLEANUP APR_FOPEN_NOCLEANUP /**< @deprecated @see APR_FOPEN_NOCLEANUP */
105 #define APR_SENDFILE_ENABLED APR_FOPEN_SENDFILE_ENABLED /**< @deprecated @see APR_FOPEN_SENDFILE_ENABLED */
106 #define APR_LARGEFILE APR_FOPEN_LARGEFILE /**< @deprecated @see APR_FOPEN_LARGEFILE */
107 
108 /** @def APR_FOPEN_LARGEFILE
109  * @warning APR_FOPEN_LARGEFILE flag only has effect on some
110  * platforms where sizeof(apr_off_t) == 4. Where implemented, it
111  * allows opening and writing to a file which exceeds the size which
112  * can be represented by apr_off_t (2 gigabytes). When a file's size
113  * does exceed 2Gb, apr_file_info_get() will fail with an error on the
114  * descriptor, likewise apr_stat()/apr_lstat() will fail on the
115  * filename. apr_dir_read() will fail with #APR_INCOMPLETE on a
116  * directory entry for a large file depending on the particular
117  * APR_FINFO_* flags. Generally, it is not recommended to use this
118  * flag.
119  *
120  * @def APR_FOPEN_SPARSE
121  * @warning APR_FOPEN_SPARSE may, depending on platform, convert a
122  * normal file to a sparse file. Some applications may be unable
123  * to decipher a sparse file, so it's critical that the sparse file
124  * flag should only be used for files accessed only by APR or other
125  * applications known to be able to decipher them. APR does not
126  * guarantee that it will compress the file into sparse segments
127  * if it was previously created and written without the sparse flag.
128  * On platforms which do not understand, or on file systems which
129  * cannot handle sparse files, the flag is ignored by apr_file_open().
130  *
131  * @def APR_FOPEN_NONBLOCK
132  * @warning APR_FOPEN_NONBLOCK is not implemented on all platforms.
133  * Callers should be prepared for it to fail with #APR_ENOTIMPL.
134  */
135 
136 /** @} */
137 
138 /**
139  * @defgroup apr_file_seek_flags File Seek Flags
140  * @{
141  */
142 
143 /* flags for apr_file_seek */
144 /** Set the file position */
145 #define APR_SET SEEK_SET
146 /** Current */
147 #define APR_CUR SEEK_CUR
148 /** Go to end of file */
149 #define APR_END SEEK_END
150 /** @} */
151 
152 /**
153  * @defgroup apr_file_attrs_set_flags File Attribute Flags
154  * @{
155  */
156 
157 /* flags for apr_file_attrs_set */
158 #define APR_FILE_ATTR_READONLY 0x01 /**< File is read-only */
159 #define APR_FILE_ATTR_EXECUTABLE 0x02 /**< File is executable */
160 #define APR_FILE_ATTR_HIDDEN 0x04 /**< File is hidden */
161 /** @} */
162 
163 /**
164  * @defgroup apr_file_writev{_full} max iovec size
165  * @{
166  */
167 #if defined(DOXYGEN)
168 #define APR_MAX_IOVEC_SIZE 1024 /**< System dependent maximum
169  size of an iovec array */
170 #elif defined(IOV_MAX)
171 #define APR_MAX_IOVEC_SIZE IOV_MAX
172 #elif defined(MAX_IOVEC)
173 #define APR_MAX_IOVEC_SIZE MAX_IOVEC
174 #else
175 #define APR_MAX_IOVEC_SIZE 1024
176 #endif
177 /** @} */
179 /** File attributes */
180 typedef apr_uint32_t apr_fileattrs_t;
181 
182 /** Type to pass as whence argument to apr_file_seek. */
183 typedef int apr_seek_where_t;
184 
185 /**
186  * Structure for referencing files.
187  */
188 typedef struct apr_file_t apr_file_t;
189 
190 /* File lock types/flags */
191 /**
192  * @defgroup apr_file_lock_types File Lock Types
193  * @{
194  */
195 
196 #define APR_FLOCK_SHARED 1 /**< Shared lock. More than one process
197  or thread can hold a shared lock
198  at any given time. Essentially,
199  this is a "read lock", preventing
200  writers from establishing an
201  exclusive lock. */
202 #define APR_FLOCK_EXCLUSIVE 2 /**< Exclusive lock. Only one process
203  may hold an exclusive lock at any
204  given time. This is analogous to
205  a "write lock". */
206 
207 #define APR_FLOCK_TYPEMASK 0x000F /**< mask to extract lock type */
208 #define APR_FLOCK_NONBLOCK 0x0010 /**< do not block while acquiring the
209  file lock */
210 /** @} */
211 
212 /**
213  * Open the specified file.
214  * @param newf The opened file descriptor.
215  * @param fname The full path to the file (using / on all systems)
216  * @param flag Or'ed value of:
217  * @li #APR_FOPEN_READ open for reading
218  * @li #APR_FOPEN_WRITE open for writing
219  * @li #APR_FOPEN_CREATE create the file if not there
220  * @li #APR_FOPEN_APPEND file ptr is set to end prior to all writes
221  * @li #APR_FOPEN_TRUNCATE set length to zero if file exists
222  * @li #APR_FOPEN_BINARY not a text file
223  * @li #APR_FOPEN_BUFFERED buffer the data. Default is non-buffered
224  * @li #APR_FOPEN_EXCL return error if #APR_FOPEN_CREATE and file exists
225  * @li #APR_FOPEN_DELONCLOSE delete the file after closing
226  * @li #APR_FOPEN_XTHREAD Platform dependent tag to open the file
227  * for use across multiple threads
228  * @li #APR_FOPEN_SHARELOCK Platform dependent support for higher
229  * level locked read/write access to support
230  * writes across process/machines
231  * @li #APR_FOPEN_NOCLEANUP Do not register a cleanup with the pool
232  * passed in on the @a pool argument (see below)
233  * @li #APR_FOPEN_SENDFILE_ENABLED Open with appropriate platform semantics
234  * for sendfile operations. Advisory only,
235  * apr_socket_sendfile does not check this flag
236  * @li #APR_FOPEN_LARGEFILE Platform dependent flag to enable large file
237  * support, see WARNING below
238  * @li #APR_FOPEN_SPARSE Platform dependent flag to enable sparse file
239  * support, see WARNING below
240  * @li #APR_FOPEN_NONBLOCK Platform dependent flag to enable
241  * non blocking file io
242  * @param perm Access permissions for file.
243  * @param pool The pool to use.
244  * @remark If perm is #APR_FPROT_OS_DEFAULT and the file is being created,
245  * appropriate default permissions will be used.
246  * @remark By default, the returned file descriptor will not be
247  * inherited by child processes created by apr_proc_create(). This
248  * can be changed using apr_file_inherit_set().
249  */
250 APR_DECLARE(apr_status_t) apr_file_open(apr_file_t **newf, const char *fname,
251  apr_int32_t flag, apr_fileperms_t perm,
252  apr_pool_t *pool);
253 
254 /**
255  * Close the specified file.
256  * @param file The file descriptor to close.
257  */
259 
260 /**
261  * Delete the specified file.
262  * @param path The full path to the file (using / on all systems)
263  * @param pool The pool to use.
264  * @remark If the file is open, it won't be removed until all
265  * instances are closed.
266  */
267 APR_DECLARE(apr_status_t) apr_file_remove(const char *path, apr_pool_t *pool);
268 
269 /**
270  * Rename the specified file.
271  * @param from_path The full path to the original file (using / on all systems)
272  * @param to_path The full path to the new file (using / on all systems)
273  * @param pool The pool to use.
274  * @warning If a file exists at the new location, then it will be
275  * overwritten. Moving files or directories across devices may not be
276  * possible.
277  */
278 APR_DECLARE(apr_status_t) apr_file_rename(const char *from_path,
279  const char *to_path,
280  apr_pool_t *pool);
281 
282 /**
283  * Create a hard link to the specified file.
284  * @param from_path The full path to the original file (using / on all systems)
285  * @param to_path The full path to the new file (using / on all systems)
286  * @remark Both files must reside on the same device.
287  */
288 APR_DECLARE(apr_status_t) apr_file_link(const char *from_path,
289  const char *to_path);
290 
291 /**
292  * Copy the specified file to another file.
293  * @param from_path The full path to the original file (using / on all systems)
294  * @param to_path The full path to the new file (using / on all systems)
295  * @param perms Access permissions for the new file if it is created.
296  * In place of the usual or'd combination of file permissions, the
297  * value #APR_FPROT_FILE_SOURCE_PERMS may be given, in which case the source
298  * file's permissions are copied.
299  * @param pool The pool to use.
300  * @remark The new file does not need to exist, it will be created if required.
301  * @warning If the new file already exists, its contents will be overwritten.
302  */
303 APR_DECLARE(apr_status_t) apr_file_copy(const char *from_path,
304  const char *to_path,
305  apr_fileperms_t perms,
306  apr_pool_t *pool);
307 
308 /**
309  * Append the specified file to another file.
310  * @param from_path The full path to the source file (use / on all systems)
311  * @param to_path The full path to the destination file (use / on all systems)
312  * @param perms Access permissions for the destination file if it is created.
313  * In place of the usual or'd combination of file permissions, the
314  * value #APR_FPROT_FILE_SOURCE_PERMS may be given, in which case the source
315  * file's permissions are copied.
316  * @param pool The pool to use.
317  * @remark The new file does not need to exist, it will be created if required.
318  */
319 APR_DECLARE(apr_status_t) apr_file_append(const char *from_path,
320  const char *to_path,
321  apr_fileperms_t perms,
322  apr_pool_t *pool);
323 
324 /**
325  * Are we at the end of the file
326  * @param fptr The apr file we are testing.
327  * @remark Returns #APR_EOF if we are at the end of file, #APR_SUCCESS otherwise.
328  */
330 
331 /**
332  * Open standard error as an apr file pointer.
333  * @param thefile The apr file to use as stderr.
334  * @param pool The pool to allocate the file out of.
335  *
336  * @remark The only reason that the apr_file_open_std* functions exist
337  * is that you may not always have a stderr/out/in on Windows. This
338  * is generally a problem with newer versions of Windows and services.
339  *
340  * @remark The other problem is that the C library functions generally work
341  * differently on Windows and Unix. So, by using apr_file_open_std*
342  * functions, you can get a handle to an APR struct that works with
343  * the APR functions which are supposed to work identically on all
344  * platforms.
345  */
347  apr_pool_t *pool);
348 
349 /**
350  * open standard output as an apr file pointer.
351  * @param thefile The apr file to use as stdout.
352  * @param pool The pool to allocate the file out of.
353  *
354  * @remark See remarks for apr_file_open_stderr().
355  */
357  apr_pool_t *pool);
358 
359 /**
360  * open standard input as an apr file pointer.
361  * @param thefile The apr file to use as stdin.
362  * @param pool The pool to allocate the file out of.
363  *
364  * @remark See remarks for apr_file_open_stderr().
365  */
367  apr_pool_t *pool);
368 
369 /**
370  * open standard error as an apr file pointer, with flags.
371  * @param thefile The apr file to use as stderr.
372  * @param flags The flags to open the file with. Only the
373  * @li #APR_FOPEN_EXCL
374  * @li #APR_FOPEN_BUFFERED
375  * @li #APR_FOPEN_XTHREAD
376  * @li #APR_FOPEN_SHARELOCK
377  * @li #APR_FOPEN_SENDFILE_ENABLED
378  * @li #APR_FOPEN_LARGEFILE
379  *
380  * flags should be used. The #APR_FOPEN_WRITE flag will
381  * be set unconditionally.
382  * @param pool The pool to allocate the file out of.
383  *
384  * @remark See remarks for apr_file_open_stderr().
385  */
387  apr_int32_t flags,
388  apr_pool_t *pool);
389 
390 /**
391  * open standard output as an apr file pointer, with flags.
392  * @param thefile The apr file to use as stdout.
393  * @param flags The flags to open the file with. Only the
394  * @li #APR_FOPEN_EXCL
395  * @li #APR_FOPEN_BUFFERED
396  * @li #APR_FOPEN_XTHREAD
397  * @li #APR_FOPEN_SHARELOCK
398  * @li #APR_FOPEN_SENDFILE_ENABLED
399  * @li #APR_FOPEN_LARGEFILE
400  *
401  * flags should be used. The #APR_FOPEN_WRITE flag will
402  * be set unconditionally.
403  * @param pool The pool to allocate the file out of.
404  *
405  * @remark See remarks for apr_file_open_stderr().
406  */
408  apr_int32_t flags,
409  apr_pool_t *pool);
410 
411 /**
412  * open standard input as an apr file pointer, with flags.
413  * @param thefile The apr file to use as stdin.
414  * @param flags The flags to open the file with. Only the
415  * @li #APR_FOPEN_EXCL
416  * @li #APR_FOPEN_BUFFERED
417  * @li #APR_FOPEN_XTHREAD
418  * @li #APR_FOPEN_SHARELOCK
419  * @li #APR_FOPEN_SENDFILE_ENABLED
420  * @li #APR_FOPEN_LARGEFILE
421  *
422  * flags should be used. The #APR_FOPEN_WRITE flag will
423  * be set unconditionally.
424  * @param pool The pool to allocate the file out of.
425  *
426  * @remark See remarks for apr_file_open_stderr().
427  */
429  apr_int32_t flags,
430  apr_pool_t *pool);
431 
432 /**
433  * Read data from the specified file.
434  * @param thefile The file descriptor to read from.
435  * @param buf The buffer to store the data to.
436  * @param nbytes On entry, the number of bytes to read; on exit, the number
437  * of bytes read.
438  *
439  * @remark apr_file_read() will read up to the specified number of
440  * bytes, but never more. If there isn't enough data to fill that
441  * number of bytes, all of the available data is read. The third
442  * argument is modified to reflect the number of bytes read. If a
443  * char was put back into the stream via ungetc, it will be the first
444  * character returned.
445  *
446  * @remark It is not possible for both bytes to be read and an #APR_EOF
447  * or other error to be returned. #APR_EINTR is never returned.
448  */
449 APR_DECLARE(apr_status_t) apr_file_read(apr_file_t *thefile, void *buf,
450  apr_size_t *nbytes);
451 
452 /**
453  * Write data to the specified file.
454  * @param thefile The file descriptor to write to.
455  * @param buf The buffer which contains the data.
456  * @param nbytes On entry, the number of bytes to write; on exit, the number
457  * of bytes written.
458  *
459  * @remark apr_file_write() will write up to the specified number of
460  * bytes, but never more. If the OS cannot write that many bytes, it
461  * will write as many as it can. The third argument is modified to
462  * reflect the * number of bytes written.
463  *
464  * @remark It is possible for both bytes to be written and an error to
465  * be returned. #APR_EINTR is never returned.
466  */
467 APR_DECLARE(apr_status_t) apr_file_write(apr_file_t *thefile, const void *buf,
468  apr_size_t *nbytes);
469 
470 /**
471  * Write data from iovec array to the specified file.
472  * @param thefile The file descriptor to write to.
473  * @param vec The array from which to get the data to write to the file.
474  * @param nvec The number of elements in the struct iovec array. This must
475  * be smaller than #APR_MAX_IOVEC_SIZE. If it isn't, the function
476  * will fail with #APR_EINVAL.
477  * @param nbytes The number of bytes written.
478  *
479  * @remark It is possible for both bytes to be written and an error to
480  * be returned. #APR_EINTR is never returned.
481  *
482  * @remark apr_file_writev() is available even if the underlying
483  * operating system doesn't provide writev().
484  */
486  const struct iovec *vec,
487  apr_size_t nvec, apr_size_t *nbytes);
488 
489 /**
490  * Read data from the specified file, ensuring that the buffer is filled
491  * before returning.
492  * @param thefile The file descriptor to read from.
493  * @param buf The buffer to store the data to.
494  * @param nbytes The number of bytes to read.
495  * @param bytes_read If non-NULL, this will contain the number of bytes read.
496  *
497  * @remark apr_file_read_full() will read up to the specified number of
498  * bytes, but never more. If there isn't enough data to fill that
499  * number of bytes, then the process/thread will block until it is
500  * available or EOF is reached. If a char was put back into the
501  * stream via ungetc, it will be the first character returned.
502  *
503  * @remark It is possible for both bytes to be read and an error to be
504  * returned. And if *bytes_read is less than nbytes, an accompanying
505  * error is _always_ returned.
506  *
507  * @remark #APR_EINTR is never returned.
508  */
510  apr_size_t nbytes,
511  apr_size_t *bytes_read);
512 
513 /**
514  * Write data to the specified file, ensuring that all of the data is
515  * written before returning.
516  * @param thefile The file descriptor to write to.
517  * @param buf The buffer which contains the data.
518  * @param nbytes The number of bytes to write.
519  * @param bytes_written If non-NULL, set to the number of bytes written.
520  *
521  * @remark apr_file_write_full() will write up to the specified number of
522  * bytes, but never more. If the OS cannot write that many bytes, the
523  * process/thread will block until they can be written. Exceptional
524  * error such as "out of space" or "pipe closed" will terminate with
525  * an error.
526  *
527  * @remark It is possible for both bytes to be written and an error to
528  * be returned. And if *bytes_written is less than nbytes, an
529  * accompanying error is _always_ returned.
530  *
531  * @remark #APR_EINTR is never returned.
532  */
534  const void *buf,
535  apr_size_t nbytes,
536  apr_size_t *bytes_written);
537 
538 
539 /**
540  * Write data from iovec array to the specified file, ensuring that all of the
541  * data is written before returning.
542  * @param thefile The file descriptor to write to.
543  * @param vec The array from which to get the data to write to the file.
544  * @param nvec The number of elements in the struct iovec array. This must
545  * be smaller than #APR_MAX_IOVEC_SIZE. If it isn't, the function
546  * will fail with #APR_EINVAL.
547  * @param nbytes The number of bytes written.
548  *
549  * @remark apr_file_writev_full() is available even if the underlying
550  * operating system doesn't provide writev().
551  */
553  const struct iovec *vec,
554  apr_size_t nvec,
555  apr_size_t *nbytes);
556 /**
557  * Write a character into the specified file.
558  * @param ch The character to write.
559  * @param thefile The file descriptor to write to
560  */
562 
563 /**
564  * Read a character from the specified file.
565  * @param ch The character to read into
566  * @param thefile The file descriptor to read from
567  */
568 APR_DECLARE(apr_status_t) apr_file_getc(char *ch, apr_file_t *thefile);
569 
570 /**
571  * Put a character back onto a specified stream.
572  * @param ch The character to write.
573  * @param thefile The file descriptor to write to
574  */
576 
577 /**
578  * Read a line from the specified file
579  * @param str The buffer to store the string in.
580  * @param len The length of the string
581  * @param thefile The file descriptor to read from
582  * @remark The buffer will be NUL-terminated if any characters are stored.
583  * The newline at the end of the line will not be stripped.
584  */
585 APR_DECLARE(apr_status_t) apr_file_gets(char *str, int len,
586  apr_file_t *thefile);
587 
588 /**
589  * Write the string into the specified file.
590  * @param str The string to write.
591  * @param thefile The file descriptor to write to
592  */
593 APR_DECLARE(apr_status_t) apr_file_puts(const char *str, apr_file_t *thefile);
594 
595 /**
596  * Flush the file's buffer.
597  * @param thefile The file descriptor to flush
598  */
600 
601 /**
602  * Transfer all file modified data and metadata to disk.
603  * @param thefile The file descriptor to sync
604  */
606 
607 /**
608  * Transfer all file modified data to disk.
609  * @param thefile The file descriptor to sync
610  */
612 
613 /**
614  * Duplicate the specified file descriptor.
615  * @param new_file The structure to duplicate into.
616  * @param old_file The file to duplicate.
617  * @param p The pool to use for the new file.
618  * @remark *new_file must point to a valid apr_file_t, or point to NULL.
619  */
621  apr_file_t *old_file,
622  apr_pool_t *p);
623 
624 /**
625  * Duplicate the specified file descriptor and close the original
626  * @param new_file The old file that is to be closed and reused
627  * @param old_file The file to duplicate
628  * @param p The pool to use for the new file
629  *
630  * @remark new_file MUST point at a valid apr_file_t. It cannot be NULL.
631  */
633  apr_file_t *old_file,
634  apr_pool_t *p);
635 
636 /**
637  * Move the specified file descriptor to a new pool
638  * @param new_file Pointer in which to return the new apr_file_t
639  * @param old_file The file to move
640  * @param p The pool to which the descriptor is to be moved
641  * @remark Unlike apr_file_dup2(), this function doesn't do an
642  * OS dup() operation on the underlying descriptor; it just
643  * moves the descriptor's apr_file_t wrapper to a new pool.
644  * @remark The new pool need not be an ancestor of old_file's pool.
645  * @remark After calling this function, old_file may not be used
646  */
648  apr_file_t *old_file,
649  apr_pool_t *p);
650 
651 /**
652  * Give the specified apr file handle a new buffer
653  * @param thefile The file handle that is to be modified
654  * @param buffer The buffer
655  * @param bufsize The size of the buffer
656  * @remark It is possible to add a buffer to previously unbuffered
657  * file handles, the #APR_FOPEN_BUFFERED flag will be added to
658  * the file handle's flags. Likewise, with buffer=NULL and
659  * bufsize=0 arguments it is possible to make a previously
660  * buffered file handle unbuffered.
661  */
663  char * buffer,
664  apr_size_t bufsize);
665 
666 /**
667  * Get the size of any buffer for the specified apr file handle
668  * @param thefile The file handle
669  */
670 APR_DECLARE(apr_size_t) apr_file_buffer_size_get(apr_file_t *thefile);
671 
672 /**
673  * Move the read/write file offset to a specified byte within a file.
674  * @param thefile The file descriptor
675  * @param where How to move the pointer, one of:
676  * @li #APR_SET -- set the offset to offset
677  * @li #APR_CUR -- add the offset to the current position
678  * @li #APR_END -- add the offset to the current file size
679  * @param offset The offset to move the pointer to.
680  * @remark The third argument is modified to be the offset the pointer
681  was actually moved to.
682  */
684  apr_seek_where_t where,
685  apr_off_t *offset);
686 
687 /**
688  * Create an anonymous pipe.
689  * @param in The newly created pipe's file for reading.
690  * @param out The newly created pipe's file for writing.
691  * @param pool The pool to operate on.
692  * @remark By default, the returned file descriptors will be inherited
693  * by child processes created using apr_proc_create(). This can be
694  * changed using apr_file_inherit_unset().
695  * @bug Some platforms cannot toggle between blocking and nonblocking,
696  * and when passing a pipe as a standard handle to an application which
697  * does not expect it, a non-blocking stream will fluxor the client app.
698  * @deprecated @see apr_file_pipe_create_ex()
699  */
701  apr_file_t **out,
702  apr_pool_t *pool);
703 
704 /**
705  * Create an anonymous pipe which portably supports async timeout options.
706  * @param in The newly created pipe's file for reading.
707  * @param out The newly created pipe's file for writing.
708  * @param blocking one of these values defined in apr_thread_proc.h;
709  * @li #APR_FULL_BLOCK
710  * @li #APR_READ_BLOCK
711  * @li #APR_WRITE_BLOCK
712  * @li #APR_FULL_NONBLOCK
713  * @param pool The pool to operate on.
714  * @remark By default, the returned file descriptors will be inherited
715  * by child processes created using apr_proc_create(). This can be
716  * changed using apr_file_inherit_unset().
717  * @remark Some platforms cannot toggle between blocking and nonblocking,
718  * and when passing a pipe as a standard handle to an application which
719  * does not expect it, a non-blocking stream will fluxor the client app.
720  * Use this function rather than apr_file_pipe_create() to create pipes
721  * where one or both ends require non-blocking semantics.
722  */
724  apr_file_t **out,
725  apr_int32_t blocking,
726  apr_pool_t *pool);
727 
728 /**
729  * Create a named pipe.
730  * @param filename The filename of the named pipe
731  * @param perm The permissions for the newly created pipe.
732  * @param pool The pool to operate on.
733  */
734 APR_DECLARE(apr_status_t) apr_file_namedpipe_create(const char *filename,
735  apr_fileperms_t perm,
736  apr_pool_t *pool);
737 
738 /**
739  * Get the timeout value for a pipe or manipulate the blocking state.
740  * @param thepipe The pipe we are getting a timeout for.
741  * @param timeout The current timeout value in microseconds.
742  */
744  apr_interval_time_t *timeout);
745 
746 /**
747  * Set the timeout value for a pipe or manipulate the blocking state.
748  * @param thepipe The pipe we are setting a timeout on.
749  * @param timeout The timeout value in microseconds. Values < 0 mean wait
750  * forever, 0 means do not wait at all.
751  */
753  apr_interval_time_t timeout);
754 
755 /** file (un)locking functions. */
756 
757 /**
758  * Establish a lock on the specified, open file. The lock may be advisory
759  * or mandatory, at the discretion of the platform. The lock applies to
760  * the file as a whole, rather than a specific range. Locks are established
761  * on a per-thread/process basis; a second lock by the same thread will not
762  * block.
763  * @param thefile The file to lock.
764  * @param type The type of lock to establish on the file.
765  */
766 APR_DECLARE(apr_status_t) apr_file_lock(apr_file_t *thefile, int type);
767 
768 /**
769  * Remove any outstanding locks on the file.
770  * @param thefile The file to unlock.
771  */
773 
774 /**accessor and general file_io functions. */
775 
776 /**
777  * return the file name of the current file.
778  * @param new_path The path of the file.
779  * @param thefile The currently open file.
780  */
781 APR_DECLARE(apr_status_t) apr_file_name_get(const char **new_path,
782  apr_file_t *thefile);
783 
784 /**
785  * Return the data associated with the current file.
786  * @param data The user data associated with the file.
787  * @param key The key to use for retrieving data associated with this file.
788  * @param file The currently open file.
789  */
790 APR_DECLARE(apr_status_t) apr_file_data_get(void **data, const char *key,
791  apr_file_t *file);
792 
793 /**
794  * Set the data associated with the current file.
795  * @param file The currently open file.
796  * @param data The user data to associate with the file.
797  * @param key The key to use for associating data with the file.
798  * @param cleanup The cleanup routine to use when the file is destroyed.
799  */
801  const char *key,
802  apr_status_t (*cleanup)(void *));
803 
804 /**
805  * Write a string to a file using a printf format.
806  * @param fptr The file to write to.
807  * @param format The format string
808  * @param ... The values to substitute in the format string
809  * @return The number of bytes written
810  */
812  const char *format, ...)
813  __attribute__((format(printf,2,3)));
814 
815 /**
816  * set the specified file's permission bits.
817  * @param fname The file (name) to apply the permissions to.
818  * @param perms The permission bits to apply to the file.
819  *
820  * @warning Some platforms may not be able to apply all of the
821  * available permission bits; #APR_INCOMPLETE will be returned if some
822  * permissions are specified which could not be set.
823  *
824  * @warning Platforms which do not implement this feature will return
825  * #APR_ENOTIMPL.
826  */
827 APR_DECLARE(apr_status_t) apr_file_perms_set(const char *fname,
828  apr_fileperms_t perms);
829 
830 /**
831  * Set attributes of the specified file.
832  * @param fname The full path to the file (using / on all systems)
833  * @param attributes Or'd combination of
834  * @li #APR_FILE_ATTR_READONLY - make the file readonly
835  * @li #APR_FILE_ATTR_EXECUTABLE - make the file executable
836  * @li #APR_FILE_ATTR_HIDDEN - make the file hidden
837  * @param attr_mask Mask of valid bits in attributes.
838  * @param pool the pool to use.
839  * @remark This function should be used in preference to explicit manipulation
840  * of the file permissions, because the operations to provide these
841  * attributes are platform specific and may involve more than simply
842  * setting permission bits.
843  * @warning Platforms which do not implement this feature will return
844  * #APR_ENOTIMPL.
845  */
846 APR_DECLARE(apr_status_t) apr_file_attrs_set(const char *fname,
847  apr_fileattrs_t attributes,
848  apr_fileattrs_t attr_mask,
849  apr_pool_t *pool);
850 
851 /**
852  * Set the mtime of the specified file.
853  * @param fname The full path to the file (using / on all systems)
854  * @param mtime The mtime to apply to the file.
855  * @param pool The pool to use.
856  * @warning Platforms which do not implement this feature will return
857  * #APR_ENOTIMPL.
858  */
859 APR_DECLARE(apr_status_t) apr_file_mtime_set(const char *fname,
860  apr_time_t mtime,
861  apr_pool_t *pool);
862 
863 /**
864  * Create a new directory on the file system.
865  * @param path the path for the directory to be created. (use / on all systems)
866  * @param perm Permissions for the new directory.
867  * @param pool the pool to use.
868  */
869 APR_DECLARE(apr_status_t) apr_dir_make(const char *path, apr_fileperms_t perm,
870  apr_pool_t *pool);
871 
872 /** Creates a new directory on the file system, but behaves like
873  * 'mkdir -p'. Creates intermediate directories as required. No error
874  * will be reported if PATH already exists.
875  * @param path the path for the directory to be created. (use / on all systems)
876  * @param perm Permissions for the new directory.
877  * @param pool the pool to use.
878  */
880  apr_fileperms_t perm,
881  apr_pool_t *pool);
882 
883 /**
884  * Remove directory from the file system.
885  * @param path the path for the directory to be removed. (use / on all systems)
886  * @param pool the pool to use.
887  * @remark Removing a directory which is in-use (e.g., the current working
888  * directory, or during apr_dir_read, or with an open file) is not portable.
889  */
890 APR_DECLARE(apr_status_t) apr_dir_remove(const char *path, apr_pool_t *pool);
891 
892 /**
893  * get the specified file's stats.
894  * @param finfo Where to store the information about the file.
895  * @param wanted The desired apr_finfo_t fields, as a bit flag of APR_FINFO_* values
896  * @param thefile The file to get information about.
897  */
899  apr_int32_t wanted,
900  apr_file_t *thefile);
901 
902 
903 /**
904  * Truncate the file's length to the specified offset
905  * @param fp The file to truncate
906  * @param offset The offset to truncate to.
907  * @remark The read/write file offset is repositioned to offset.
908  */
909 APR_DECLARE(apr_status_t) apr_file_trunc(apr_file_t *fp, apr_off_t offset);
910 
911 /**
912  * Retrieve the flags that were passed into apr_file_open()
913  * when the file was opened.
914  * @return apr_int32_t the flags
915  */
916 APR_DECLARE(apr_int32_t) apr_file_flags_get(apr_file_t *f);
917 
918 /**
919  * Get the pool used by the file.
920  */
922 
923 /**
924  * Set a file to be inherited by child processes.
925  *
926  */
928 
929 /**
930  * Unset a file from being inherited by child processes.
931  */
933 
934 /**
935  * Open a temporary file
936  * @param fp The apr file to use as a temporary file.
937  * @param templ The template to use when creating a temp file.
938  * @param flags The flags to open the file with. If this is zero,
939  * the file is opened with
940  * #APR_FOPEN_CREATE | #APR_FOPEN_READ | #APR_FOPEN_WRITE |
941  * #APR_FOPEN_EXCL | #APR_FOPEN_DELONCLOSE
942  * @param p The pool to allocate the file out of.
943  * @remark
944  * This function generates a unique temporary file name from template.
945  * The last six characters of template must be XXXXXX and these are replaced
946  * with a string that makes the filename unique. Since it will be modified,
947  * template must not be a string constant, but should be declared as a character
948  * array.
949  *
950  */
952  apr_int32_t flags, apr_pool_t *p);
953 
954 
955 /**
956  * Find an existing directory suitable as a temporary storage location.
957  * @param temp_dir The temp directory.
958  * @param p The pool to use for any necessary allocations.
959  * @remark
960  * This function uses an algorithm to search for a directory that an
961  * an application can use for temporary storage.
962  *
963  */
964 APR_DECLARE(apr_status_t) apr_temp_dir_get(const char **temp_dir,
965  apr_pool_t *p);
966 
967 /** @} */
968 
969 #ifdef __cplusplus
970 }
971 #endif
972 
973 #endif /* ! APR_FILE_IO_H */