Apache Portable Runtime

apr_file_io.h

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00001 /* Licensed to the Apache Software Foundation (ASF) under one or more
00002  * contributor license agreements.  See the NOTICE file distributed with
00003  * this work for additional information regarding copyright ownership.
00004  * The ASF licenses this file to You under the Apache License, Version 2.0
00005  * (the "License"); you may not use this file except in compliance with
00006  * the License.  You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #ifndef APR_FILE_IO_H
00018 #define APR_FILE_IO_H
00019 
00020 /**
00021  * @file apr_file_io.h
00022  * @brief APR File I/O Handling
00023  */
00024 
00025 #include "apr.h"
00026 #include "apr_pools.h"
00027 #include "apr_time.h"
00028 #include "apr_errno.h"
00029 #include "apr_file_info.h"
00030 #include "apr_inherit.h"
00031 
00032 #define APR_WANT_STDIO          /**< for SEEK_* */
00033 #define APR_WANT_IOVEC          /**< for apr_file_writev */
00034 #include "apr_want.h"
00035 
00036 #ifdef __cplusplus
00037 extern "C" {
00038 #endif /* __cplusplus */
00039 
00040 /**
00041  * @defgroup apr_file_io File I/O Handling Functions
00042  * @ingroup APR 
00043  * @{
00044  */
00045 
00046 /**
00047  * @defgroup apr_file_open_flags File Open Flags/Routines
00048  * @{
00049  */
00050 
00051 /* Note to implementors: Values in the range 0x00100000--0x80000000
00052    are reserved for platform-specific values. */
00053 
00054 #define APR_FOPEN_READ       0x00001  /**< Open the file for reading */
00055 #define APR_FOPEN_WRITE      0x00002  /**< Open the file for writing */
00056 #define APR_FOPEN_CREATE     0x00004  /**< Create the file if not there */
00057 #define APR_FOPEN_APPEND     0x00008  /**< Append to the end of the file */
00058 #define APR_FOPEN_TRUNCATE   0x00010  /**< Open the file and truncate
00059                                          to 0 length */
00060 #define APR_FOPEN_BINARY     0x00020  /**< Open the file in binary mode
00061                                          (This flag is ignored on UNIX 
00062                                          because it has no meaning)*/
00063 #define APR_FOPEN_EXCL       0x00040  /**< Open should fail if #APR_FOPEN_CREATE
00064                                          and file exists. */
00065 #define APR_FOPEN_BUFFERED   0x00080  /**< Open the file for buffered I/O */
00066 #define APR_FOPEN_DELONCLOSE 0x00100  /**< Delete the file after close */
00067 #define APR_FOPEN_XTHREAD    0x00200  /**< Platform dependent tag to open
00068                                          the file for use across multiple
00069                                          threads */
00070 #define APR_FOPEN_SHARELOCK  0x00400  /**< Platform dependent support for
00071                                          higher level locked read/write
00072                                          access to support writes across
00073                                          process/machines */
00074 #define APR_FOPEN_NOCLEANUP  0x00800  /**< Do not register a cleanup
00075                                          when the file is opened. The
00076                                          apr_os_file_t handle in apr_file_t
00077                                          will not be closed when the pool
00078                                          is destroyed. */
00079 #define APR_FOPEN_SENDFILE_ENABLED 0x01000 /**< Advisory flag that this
00080                                              file should support
00081                                              apr_socket_sendfile operation */
00082 #define APR_FOPEN_LARGEFILE   0x04000 /**< Platform dependent flag to enable
00083                                        * large file support, see WARNING below
00084                                        */
00085 #define APR_FOPEN_SPARSE      0x08000 /**< Platform dependent flag to enable
00086                                        * sparse file support, see WARNING below
00087                                        */
00088 #define APR_FOPEN_NONBLOCK    0x40000 /**< Platform dependent flag to enable
00089                                        * non blocking file io */
00090 
00091 
00092 /* backcompat */
00093 #define APR_READ             APR_FOPEN_READ       /**< @deprecated @see APR_FOPEN_READ */
00094 #define APR_WRITE            APR_FOPEN_WRITE      /**< @deprecated @see APR_FOPEN_WRITE */   
00095 #define APR_CREATE           APR_FOPEN_CREATE     /**< @deprecated @see APR_FOPEN_CREATE */   
00096 #define APR_APPEND           APR_FOPEN_APPEND     /**< @deprecated @see APR_FOPEN_APPEND */   
00097 #define APR_TRUNCATE         APR_FOPEN_TRUNCATE   /**< @deprecated @see APR_FOPEN_TRUNCATE */   
00098 #define APR_BINARY           APR_FOPEN_BINARY     /**< @deprecated @see APR_FOPEN_BINARY */   
00099 #define APR_EXCL             APR_FOPEN_EXCL       /**< @deprecated @see APR_FOPEN_EXCL */   
00100 #define APR_BUFFERED         APR_FOPEN_BUFFERED   /**< @deprecated @see APR_FOPEN_BUFFERED */   
00101 #define APR_DELONCLOSE       APR_FOPEN_DELONCLOSE /**< @deprecated @see APR_FOPEN_DELONCLOSE */   
00102 #define APR_XTHREAD          APR_FOPEN_XTHREAD    /**< @deprecated @see APR_FOPEN_XTHREAD */   
00103 #define APR_SHARELOCK        APR_FOPEN_SHARELOCK  /**< @deprecated @see APR_FOPEN_SHARELOCK */   
00104 #define APR_FILE_NOCLEANUP   APR_FOPEN_NOCLEANUP  /**< @deprecated @see APR_FOPEN_NOCLEANUP */   
00105 #define APR_SENDFILE_ENABLED APR_FOPEN_SENDFILE_ENABLED /**< @deprecated @see APR_FOPEN_SENDFILE_ENABLED */   
00106 #define APR_LARGEFILE        APR_FOPEN_LARGEFILE  /**< @deprecated @see APR_FOPEN_LARGEFILE */   
00107 
00108 /** @def APR_FOPEN_LARGEFILE 
00109  * @warning APR_FOPEN_LARGEFILE flag only has effect on some
00110  * platforms where sizeof(apr_off_t) == 4.  Where implemented, it
00111  * allows opening and writing to a file which exceeds the size which
00112  * can be represented by apr_off_t (2 gigabytes).  When a file's size
00113  * does exceed 2Gb, apr_file_info_get() will fail with an error on the
00114  * descriptor, likewise apr_stat()/apr_lstat() will fail on the
00115  * filename.  apr_dir_read() will fail with #APR_INCOMPLETE on a
00116  * directory entry for a large file depending on the particular
00117  * APR_FINFO_* flags.  Generally, it is not recommended to use this
00118  * flag.
00119  *
00120  * @def APR_FOPEN_SPARSE
00121  * @warning APR_FOPEN_SPARSE may, depending on platform, convert a
00122  * normal file to a sparse file.  Some applications may be unable
00123  * to decipher a sparse file, so it's critical that the sparse file
00124  * flag should only be used for files accessed only by APR or other
00125  * applications known to be able to decipher them.  APR does not
00126  * guarantee that it will compress the file into sparse segments
00127  * if it was previously created and written without the sparse flag.
00128  * On platforms which do not understand, or on file systems which
00129  * cannot handle sparse files, the flag is ignored by apr_file_open().
00130  *
00131  * @def APR_FOPEN_NONBLOCK
00132  * @warning APR_FOPEN_NONBLOCK is not implemented on all platforms.
00133  * Callers should be prepared for it to fail with #APR_ENOTIMPL.
00134  */
00135 
00136 /** @} */
00137 
00138 /**
00139  * @defgroup apr_file_seek_flags File Seek Flags
00140  * @{
00141  */
00142 
00143 /* flags for apr_file_seek */
00144 /** Set the file position */
00145 #define APR_SET SEEK_SET
00146 /** Current */
00147 #define APR_CUR SEEK_CUR
00148 /** Go to end of file */
00149 #define APR_END SEEK_END
00150 /** @} */
00151 
00152 /**
00153  * @defgroup apr_file_attrs_set_flags File Attribute Flags
00154  * @{
00155  */
00156 
00157 /* flags for apr_file_attrs_set */
00158 #define APR_FILE_ATTR_READONLY   0x01          /**< File is read-only */
00159 #define APR_FILE_ATTR_EXECUTABLE 0x02          /**< File is executable */
00160 #define APR_FILE_ATTR_HIDDEN     0x04          /**< File is hidden */
00161 /** @} */
00162 
00163 /**
00164  * @defgroup apr_file_writev{_full} max iovec size
00165  * @{
00166  */
00167 #if defined(DOXYGEN)
00168 #define APR_MAX_IOVEC_SIZE 1024                /**< System dependent maximum 
00169                                                     size of an iovec array */
00170 #elif defined(IOV_MAX)
00171 #define APR_MAX_IOVEC_SIZE IOV_MAX
00172 #elif defined(MAX_IOVEC)
00173 #define APR_MAX_IOVEC_SIZE MAX_IOVEC
00174 #else
00175 #define APR_MAX_IOVEC_SIZE 1024
00176 #endif
00177 /** @} */
00178 
00179 /** File attributes */
00180 typedef apr_uint32_t apr_fileattrs_t;
00181 
00182 /** Type to pass as whence argument to apr_file_seek. */
00183 typedef int       apr_seek_where_t;
00184 
00185 /**
00186  * Structure for referencing files.
00187  */
00188 typedef struct apr_file_t         apr_file_t;
00189 
00190 /* File lock types/flags */
00191 /**
00192  * @defgroup apr_file_lock_types File Lock Types
00193  * @{
00194  */
00195 
00196 #define APR_FLOCK_SHARED        1       /**< Shared lock. More than one process
00197                                            or thread can hold a shared lock
00198                                            at any given time. Essentially,
00199                                            this is a "read lock", preventing
00200                                            writers from establishing an
00201                                            exclusive lock. */
00202 #define APR_FLOCK_EXCLUSIVE     2       /**< Exclusive lock. Only one process
00203                                            may hold an exclusive lock at any
00204                                            given time. This is analogous to
00205                                            a "write lock". */
00206 
00207 #define APR_FLOCK_TYPEMASK      0x000F  /**< mask to extract lock type */
00208 #define APR_FLOCK_NONBLOCK      0x0010  /**< do not block while acquiring the
00209                                            file lock */
00210 /** @} */
00211 
00212 /**
00213  * Open the specified file.
00214  * @param newf The opened file descriptor.
00215  * @param fname The full path to the file (using / on all systems)
00216  * @param flag Or'ed value of:
00217  * @li #APR_FOPEN_READ           open for reading
00218  * @li #APR_FOPEN_WRITE          open for writing
00219  * @li #APR_FOPEN_CREATE         create the file if not there
00220  * @li #APR_FOPEN_APPEND         file ptr is set to end prior to all writes
00221  * @li #APR_FOPEN_TRUNCATE       set length to zero if file exists
00222  * @li #APR_FOPEN_BINARY         not a text file
00223  * @li #APR_FOPEN_BUFFERED       buffer the data.  Default is non-buffered
00224  * @li #APR_FOPEN_EXCL           return error if #APR_FOPEN_CREATE and file exists
00225  * @li #APR_FOPEN_DELONCLOSE     delete the file after closing
00226  * @li #APR_FOPEN_XTHREAD        Platform dependent tag to open the file
00227  *                               for use across multiple threads
00228  * @li #APR_FOPEN_SHARELOCK      Platform dependent support for higher
00229  *                               level locked read/write access to support
00230  *                               writes across process/machines
00231  * @li #APR_FOPEN_NOCLEANUP      Do not register a cleanup with the pool 
00232  *                               passed in on the @a pool argument (see below)
00233  * @li #APR_FOPEN_SENDFILE_ENABLED  Open with appropriate platform semantics
00234  *                               for sendfile operations.  Advisory only,
00235  *                               apr_socket_sendfile does not check this flag
00236  * @li #APR_FOPEN_LARGEFILE      Platform dependent flag to enable large file
00237  *                               support, see WARNING below 
00238  * @li #APR_FOPEN_SPARSE         Platform dependent flag to enable sparse file
00239  *                               support, see WARNING below
00240  * @li #APR_FOPEN_ROTATING       Do file file rotation checking
00241  * @li #APR_FOPEN_MANUAL_ROTATE  Enable Manual rotation
00242  * @li #APR_FOPEN_NONBLOCK       Platform dependent flag to enable
00243  *                               non blocking file io
00244  * @param perm Access permissions for file.
00245  * @param pool The pool to use.
00246  * @remark If perm is #APR_FPROT_OS_DEFAULT and the file is being created,
00247  * appropriate default permissions will be used.
00248  * @remark By default, the returned file descriptor will not be
00249  * inherited by child processes created by apr_proc_create().  This
00250  * can be changed using apr_file_inherit_set().
00251  */
00252 APR_DECLARE(apr_status_t) apr_file_open(apr_file_t **newf, const char *fname,
00253                                         apr_int32_t flag, apr_fileperms_t perm,
00254                                         apr_pool_t *pool);
00255 
00256 /**
00257  * Close the specified file.
00258  * @param file The file descriptor to close.
00259  */
00260 APR_DECLARE(apr_status_t) apr_file_close(apr_file_t *file);
00261 
00262 /**
00263  * Delete the specified file.
00264  * @param path The full path to the file (using / on all systems)
00265  * @param pool The pool to use.
00266  * @remark If the file is open, it won't be removed until all
00267  * instances are closed.
00268  */
00269 APR_DECLARE(apr_status_t) apr_file_remove(const char *path, apr_pool_t *pool);
00270 
00271 /**
00272  * Rename the specified file.
00273  * @param from_path The full path to the original file (using / on all systems)
00274  * @param to_path The full path to the new file (using / on all systems)
00275  * @param pool The pool to use.
00276  * @warning If a file exists at the new location, then it will be
00277  * overwritten.  Moving files or directories across devices may not be
00278  * possible.
00279  */
00280 APR_DECLARE(apr_status_t) apr_file_rename(const char *from_path, 
00281                                           const char *to_path,
00282                                           apr_pool_t *pool);
00283 
00284 /**
00285  * Create a hard link to the specified file.
00286  * @param from_path The full path to the original file (using / on all systems)
00287  * @param to_path The full path to the new file (using / on all systems)
00288  * @remark Both files must reside on the same device.
00289  */
00290 APR_DECLARE(apr_status_t) apr_file_link(const char *from_path, 
00291                                           const char *to_path);
00292 
00293 /**
00294  * Copy the specified file to another file.
00295  * @param from_path The full path to the original file (using / on all systems)
00296  * @param to_path The full path to the new file (using / on all systems)
00297  * @param perms Access permissions for the new file if it is created.
00298  *     In place of the usual or'd combination of file permissions, the
00299  *     value #APR_FPROT_FILE_SOURCE_PERMS may be given, in which case the source
00300  *     file's permissions are copied.
00301  * @param pool The pool to use.
00302  * @remark The new file does not need to exist, it will be created if required.
00303  * @warning If the new file already exists, its contents will be overwritten.
00304  */
00305 APR_DECLARE(apr_status_t) apr_file_copy(const char *from_path, 
00306                                         const char *to_path,
00307                                         apr_fileperms_t perms,
00308                                         apr_pool_t *pool);
00309 
00310 /**
00311  * Append the specified file to another file.
00312  * @param from_path The full path to the source file (use / on all systems)
00313  * @param to_path The full path to the destination file (use / on all systems)
00314  * @param perms Access permissions for the destination file if it is created.
00315  *     In place of the usual or'd combination of file permissions, the
00316  *     value #APR_FPROT_FILE_SOURCE_PERMS may be given, in which case the source
00317  *     file's permissions are copied.
00318  * @param pool The pool to use.
00319  * @remark The new file does not need to exist, it will be created if required.
00320  */
00321 APR_DECLARE(apr_status_t) apr_file_append(const char *from_path, 
00322                                           const char *to_path,
00323                                           apr_fileperms_t perms,
00324                                           apr_pool_t *pool);
00325 
00326 /**
00327  * Are we at the end of the file
00328  * @param fptr The apr file we are testing.
00329  * @remark Returns #APR_EOF if we are at the end of file, #APR_SUCCESS otherwise.
00330  */
00331 APR_DECLARE(apr_status_t) apr_file_eof(apr_file_t *fptr);
00332 
00333 /**
00334  * Open standard error as an apr file pointer.
00335  * @param thefile The apr file to use as stderr.
00336  * @param pool The pool to allocate the file out of.
00337  * 
00338  * @remark The only reason that the apr_file_open_std* functions exist
00339  * is that you may not always have a stderr/out/in on Windows.  This
00340  * is generally a problem with newer versions of Windows and services.
00341  * 
00342  * @remark The other problem is that the C library functions generally work
00343  * differently on Windows and Unix.  So, by using apr_file_open_std*
00344  * functions, you can get a handle to an APR struct that works with
00345  * the APR functions which are supposed to work identically on all
00346  * platforms.
00347  */
00348 APR_DECLARE(apr_status_t) apr_file_open_stderr(apr_file_t **thefile,
00349                                                apr_pool_t *pool);
00350 
00351 /**
00352  * open standard output as an apr file pointer.
00353  * @param thefile The apr file to use as stdout.
00354  * @param pool The pool to allocate the file out of.
00355  * 
00356  * @remark See remarks for apr_file_open_stderr().
00357  */
00358 APR_DECLARE(apr_status_t) apr_file_open_stdout(apr_file_t **thefile,
00359                                                apr_pool_t *pool);
00360 
00361 /**
00362  * open standard input as an apr file pointer.
00363  * @param thefile The apr file to use as stdin.
00364  * @param pool The pool to allocate the file out of.
00365  * 
00366  * @remark See remarks for apr_file_open_stderr().
00367  */
00368 APR_DECLARE(apr_status_t) apr_file_open_stdin(apr_file_t **thefile,
00369                                               apr_pool_t *pool);
00370 
00371 /**
00372  * open standard error as an apr file pointer, with flags.
00373  * @param thefile The apr file to use as stderr.
00374  * @param flags The flags to open the file with. Only the 
00375  *              @li #APR_FOPEN_EXCL
00376  *              @li #APR_FOPEN_BUFFERED
00377  *              @li #APR_FOPEN_XTHREAD
00378  *              @li #APR_FOPEN_SHARELOCK 
00379  *              @li #APR_FOPEN_SENDFILE_ENABLED
00380  *              @li #APR_FOPEN_LARGEFILE
00381  *
00382  *              flags should be used. The #APR_FOPEN_WRITE flag will
00383  *              be set unconditionally.
00384  * @param pool The pool to allocate the file out of.
00385  * 
00386  * @remark See remarks for apr_file_open_stderr().
00387  */
00388 APR_DECLARE(apr_status_t) apr_file_open_flags_stderr(apr_file_t **thefile,
00389                                                      apr_int32_t flags,
00390                                                      apr_pool_t *pool);
00391 
00392 /**
00393  * open standard output as an apr file pointer, with flags.
00394  * @param thefile The apr file to use as stdout.
00395  * @param flags The flags to open the file with. Only the 
00396  *              @li #APR_FOPEN_EXCL
00397  *              @li #APR_FOPEN_BUFFERED
00398  *              @li #APR_FOPEN_XTHREAD
00399  *              @li #APR_FOPEN_SHARELOCK 
00400  *              @li #APR_FOPEN_SENDFILE_ENABLED
00401  *              @li #APR_FOPEN_LARGEFILE
00402  *
00403  *              flags should be used. The #APR_FOPEN_WRITE flag will
00404  *              be set unconditionally.
00405  * @param pool The pool to allocate the file out of.
00406  * 
00407  * @remark See remarks for apr_file_open_stderr().
00408  */
00409 APR_DECLARE(apr_status_t) apr_file_open_flags_stdout(apr_file_t **thefile,
00410                                                      apr_int32_t flags,
00411                                                      apr_pool_t *pool);
00412 
00413 /**
00414  * open standard input as an apr file pointer, with flags.
00415  * @param thefile The apr file to use as stdin.
00416  * @param flags The flags to open the file with. Only the 
00417  *              @li #APR_FOPEN_EXCL
00418  *              @li #APR_FOPEN_BUFFERED
00419  *              @li #APR_FOPEN_XTHREAD
00420  *              @li #APR_FOPEN_SHARELOCK 
00421  *              @li #APR_FOPEN_SENDFILE_ENABLED
00422  *              @li #APR_FOPEN_LARGEFILE
00423  *
00424  *              flags should be used. The #APR_FOPEN_WRITE flag will
00425  *              be set unconditionally.
00426  * @param pool The pool to allocate the file out of.
00427  * 
00428  * @remark See remarks for apr_file_open_stderr().
00429  */
00430 APR_DECLARE(apr_status_t) apr_file_open_flags_stdin(apr_file_t **thefile,
00431                                                      apr_int32_t flags,
00432                                                      apr_pool_t *pool);
00433 
00434 /**
00435  * Read data from the specified file.
00436  * @param thefile The file descriptor to read from.
00437  * @param buf The buffer to store the data to.
00438  * @param nbytes On entry, the number of bytes to read; on exit, the number
00439  * of bytes read.
00440  *
00441  * @remark apr_file_read() will read up to the specified number of
00442  * bytes, but never more.  If there isn't enough data to fill that
00443  * number of bytes, all of the available data is read.  The third
00444  * argument is modified to reflect the number of bytes read.  If a
00445  * char was put back into the stream via ungetc, it will be the first
00446  * character returned.
00447  *
00448  * @remark It is not possible for both bytes to be read and an #APR_EOF
00449  * or other error to be returned.  #APR_EINTR is never returned.
00450  */
00451 APR_DECLARE(apr_status_t) apr_file_read(apr_file_t *thefile, void *buf,
00452                                         apr_size_t *nbytes);
00453 
00454 /**
00455  * Write data to the specified file.
00456  * @param thefile The file descriptor to write to.
00457  * @param buf The buffer which contains the data.
00458  * @param nbytes On entry, the number of bytes to write; on exit, the number 
00459  *               of bytes written.
00460  *
00461  * @remark apr_file_write() will write up to the specified number of
00462  * bytes, but never more.  If the OS cannot write that many bytes, it
00463  * will write as many as it can.  The third argument is modified to
00464  * reflect the * number of bytes written.
00465  *
00466  * @remark It is possible for both bytes to be written and an error to
00467  * be returned.  #APR_EINTR is never returned.
00468  */
00469 APR_DECLARE(apr_status_t) apr_file_write(apr_file_t *thefile, const void *buf,
00470                                          apr_size_t *nbytes);
00471 
00472 /**
00473  * Write data from iovec array to the specified file.
00474  * @param thefile The file descriptor to write to.
00475  * @param vec The array from which to get the data to write to the file.
00476  * @param nvec The number of elements in the struct iovec array. This must 
00477  *             be smaller than #APR_MAX_IOVEC_SIZE.  If it isn't, the function 
00478  *             will fail with #APR_EINVAL.
00479  * @param nbytes The number of bytes written.
00480  *
00481  * @remark It is possible for both bytes to be written and an error to
00482  * be returned.  #APR_EINTR is never returned.
00483  *
00484  * @remark apr_file_writev() is available even if the underlying
00485  * operating system doesn't provide writev().
00486  */
00487 APR_DECLARE(apr_status_t) apr_file_writev(apr_file_t *thefile,
00488                                           const struct iovec *vec,
00489                                           apr_size_t nvec, apr_size_t *nbytes);
00490 
00491 /**
00492  * Read data from the specified file, ensuring that the buffer is filled
00493  * before returning.
00494  * @param thefile The file descriptor to read from.
00495  * @param buf The buffer to store the data to.
00496  * @param nbytes The number of bytes to read.
00497  * @param bytes_read If non-NULL, this will contain the number of bytes read.
00498  *
00499  * @remark apr_file_read_full() will read up to the specified number of
00500  * bytes, but never more.  If there isn't enough data to fill that
00501  * number of bytes, then the process/thread will block until it is
00502  * available or EOF is reached.  If a char was put back into the
00503  * stream via ungetc, it will be the first character returned.
00504  *
00505  * @remark It is possible for both bytes to be read and an error to be
00506  * returned.  And if *bytes_read is less than nbytes, an accompanying
00507  * error is _always_ returned.
00508  *
00509  * @remark #APR_EINTR is never returned.
00510  */
00511 APR_DECLARE(apr_status_t) apr_file_read_full(apr_file_t *thefile, void *buf,
00512                                              apr_size_t nbytes,
00513                                              apr_size_t *bytes_read);
00514 
00515 /**
00516  * Write data to the specified file, ensuring that all of the data is
00517  * written before returning.
00518  * @param thefile The file descriptor to write to.
00519  * @param buf The buffer which contains the data.
00520  * @param nbytes The number of bytes to write.
00521  * @param bytes_written If non-NULL, set to the number of bytes written.
00522  * 
00523  * @remark apr_file_write_full() will write up to the specified number of
00524  * bytes, but never more.  If the OS cannot write that many bytes, the
00525  * process/thread will block until they can be written. Exceptional
00526  * error such as "out of space" or "pipe closed" will terminate with
00527  * an error.
00528  *
00529  * @remark It is possible for both bytes to be written and an error to
00530  * be returned.  And if *bytes_written is less than nbytes, an
00531  * accompanying error is _always_ returned.
00532  *
00533  * @remark #APR_EINTR is never returned.
00534  */
00535 APR_DECLARE(apr_status_t) apr_file_write_full(apr_file_t *thefile, 
00536                                               const void *buf,
00537                                               apr_size_t nbytes, 
00538                                               apr_size_t *bytes_written);
00539 
00540 
00541 /**
00542  * Write data from iovec array to the specified file, ensuring that all of the
00543  * data is written before returning.
00544  * @param thefile The file descriptor to write to.
00545  * @param vec The array from which to get the data to write to the file.
00546  * @param nvec The number of elements in the struct iovec array. This must 
00547  *             be smaller than #APR_MAX_IOVEC_SIZE.  If it isn't, the function 
00548  *             will fail with #APR_EINVAL.
00549  * @param nbytes The number of bytes written.
00550  *
00551  * @remark apr_file_writev_full() is available even if the underlying
00552  * operating system doesn't provide writev().
00553  */
00554 APR_DECLARE(apr_status_t) apr_file_writev_full(apr_file_t *thefile,
00555                                                const struct iovec *vec,
00556                                                apr_size_t nvec,
00557                                                apr_size_t *nbytes);
00558 /**
00559  * Write a character into the specified file.
00560  * @param ch The character to write.
00561  * @param thefile The file descriptor to write to
00562  */
00563 APR_DECLARE(apr_status_t) apr_file_putc(char ch, apr_file_t *thefile);
00564 
00565 /**
00566  * Read a character from the specified file.
00567  * @param ch The character to read into
00568  * @param thefile The file descriptor to read from
00569  */
00570 APR_DECLARE(apr_status_t) apr_file_getc(char *ch, apr_file_t *thefile);
00571 
00572 /**
00573  * Put a character back onto a specified stream.
00574  * @param ch The character to write.
00575  * @param thefile The file descriptor to write to
00576  */
00577 APR_DECLARE(apr_status_t) apr_file_ungetc(char ch, apr_file_t *thefile);
00578 
00579 /**
00580  * Read a line from the specified file
00581  * @param str The buffer to store the string in. 
00582  * @param len The length of the string
00583  * @param thefile The file descriptor to read from
00584  * @remark The buffer will be NUL-terminated if any characters are stored.
00585  *         The newline at the end of the line will not be stripped.
00586  */
00587 APR_DECLARE(apr_status_t) apr_file_gets(char *str, int len, 
00588                                         apr_file_t *thefile);
00589 
00590 /**
00591  * Write the string into the specified file.
00592  * @param str The string to write. 
00593  * @param thefile The file descriptor to write to
00594  */
00595 APR_DECLARE(apr_status_t) apr_file_puts(const char *str, apr_file_t *thefile);
00596 
00597 /**
00598  * Flush the file's buffer.
00599  * @param thefile The file descriptor to flush
00600  */
00601 APR_DECLARE(apr_status_t) apr_file_flush(apr_file_t *thefile);
00602 
00603 /**
00604  * Transfer all file modified data and metadata to disk.
00605  * @param thefile The file descriptor to sync
00606  */
00607 APR_DECLARE(apr_status_t) apr_file_sync(apr_file_t *thefile);
00608 
00609 /**
00610  * Transfer all file modified data to disk.
00611  * @param thefile The file descriptor to sync
00612  */
00613 APR_DECLARE(apr_status_t) apr_file_datasync(apr_file_t *thefile);
00614 
00615 /**
00616  * Duplicate the specified file descriptor.
00617  * @param new_file The structure to duplicate into. 
00618  * @param old_file The file to duplicate.
00619  * @param p The pool to use for the new file.
00620  * @remark *new_file must point to a valid apr_file_t, or point to NULL.
00621  */         
00622 APR_DECLARE(apr_status_t) apr_file_dup(apr_file_t **new_file,
00623                                        apr_file_t *old_file,
00624                                        apr_pool_t *p);
00625 
00626 /**
00627  * Duplicate the specified file descriptor and close the original
00628  * @param new_file The old file that is to be closed and reused
00629  * @param old_file The file to duplicate
00630  * @param p        The pool to use for the new file
00631  *
00632  * @remark new_file MUST point at a valid apr_file_t. It cannot be NULL.
00633  */
00634 APR_DECLARE(apr_status_t) apr_file_dup2(apr_file_t *new_file,
00635                                         apr_file_t *old_file,
00636                                         apr_pool_t *p);
00637 
00638 /**
00639  * Move the specified file descriptor to a new pool
00640  * @param new_file Pointer in which to return the new apr_file_t
00641  * @param old_file The file to move
00642  * @param p        The pool to which the descriptor is to be moved
00643  * @remark Unlike apr_file_dup2(), this function doesn't do an
00644  *         OS dup() operation on the underlying descriptor; it just
00645  *         moves the descriptor's apr_file_t wrapper to a new pool.
00646  * @remark The new pool need not be an ancestor of old_file's pool.
00647  * @remark After calling this function, old_file may not be used
00648  */
00649 APR_DECLARE(apr_status_t) apr_file_setaside(apr_file_t **new_file,
00650                                             apr_file_t *old_file,
00651                                             apr_pool_t *p);
00652 
00653 /**
00654  * Give the specified apr file handle a new buffer 
00655  * @param thefile  The file handle that is to be modified
00656  * @param buffer   The buffer
00657  * @param bufsize  The size of the buffer
00658  * @remark It is possible to add a buffer to previously unbuffered
00659  *         file handles, the #APR_FOPEN_BUFFERED flag will be added to
00660  *         the file handle's flags. Likewise, with buffer=NULL and
00661  *         bufsize=0 arguments it is possible to make a previously
00662  *         buffered file handle unbuffered.
00663  */
00664 APR_DECLARE(apr_status_t) apr_file_buffer_set(apr_file_t *thefile,
00665                                               char * buffer,
00666                                               apr_size_t bufsize);
00667 
00668 /**
00669  * Get the size of any buffer for the specified apr file handle 
00670  * @param thefile  The file handle 
00671  */
00672 APR_DECLARE(apr_size_t) apr_file_buffer_size_get(apr_file_t *thefile);
00673 
00674 /**
00675  * Move the read/write file offset to a specified byte within a file.
00676  * @param thefile The file descriptor
00677  * @param where How to move the pointer, one of:
00678  *              @li #APR_SET  --  set the offset to offset
00679  *              @li #APR_CUR  --  add the offset to the current position 
00680  *              @li #APR_END  --  add the offset to the current file size 
00681  * @param offset The offset to move the pointer to.
00682  * @remark The third argument is modified to be the offset the pointer
00683           was actually moved to.
00684  */
00685 APR_DECLARE(apr_status_t) apr_file_seek(apr_file_t *thefile, 
00686                                    apr_seek_where_t where,
00687                                    apr_off_t *offset);
00688 
00689 /**
00690  * Create an anonymous pipe.
00691  * @param in The newly created pipe's file for reading.
00692  * @param out The newly created pipe's file for writing.
00693  * @param pool The pool to operate on.
00694  * @remark By default, the returned file descriptors will be inherited
00695  * by child processes created using apr_proc_create().  This can be
00696  * changed using apr_file_inherit_unset().
00697  * @bug  Some platforms cannot toggle between blocking and nonblocking,
00698  * and when passing a pipe as a standard handle to an application which
00699  * does not expect it, a non-blocking stream will fluxor the client app.
00700  * @deprecated @see apr_file_pipe_create_ex()
00701  */
00702 APR_DECLARE(apr_status_t) apr_file_pipe_create(apr_file_t **in, 
00703                                                apr_file_t **out,
00704                                                apr_pool_t *pool);
00705 
00706 /**
00707  * Create an anonymous pipe which portably supports async timeout options.
00708  * @param in The newly created pipe's file for reading.
00709  * @param out The newly created pipe's file for writing.
00710  * @param blocking one of these values defined in apr_thread_proc.h;
00711  *                 @li #APR_FULL_BLOCK
00712  *                 @li #APR_READ_BLOCK
00713  *                 @li #APR_WRITE_BLOCK
00714  *                 @li #APR_FULL_NONBLOCK
00715  * @param pool The pool to operate on.
00716  * @remark By default, the returned file descriptors will be inherited
00717  * by child processes created using apr_proc_create().  This can be
00718  * changed using apr_file_inherit_unset().
00719  * @remark Some platforms cannot toggle between blocking and nonblocking,
00720  * and when passing a pipe as a standard handle to an application which
00721  * does not expect it, a non-blocking stream will fluxor the client app.
00722  * Use this function rather than apr_file_pipe_create() to create pipes 
00723  * where one or both ends require non-blocking semantics.
00724  */
00725 APR_DECLARE(apr_status_t) apr_file_pipe_create_ex(apr_file_t **in, 
00726                                                   apr_file_t **out, 
00727                                                   apr_int32_t blocking, 
00728                                                   apr_pool_t *pool);
00729 
00730 /**
00731  * Create a named pipe.
00732  * @param filename The filename of the named pipe
00733  * @param perm The permissions for the newly created pipe.
00734  * @param pool The pool to operate on.
00735  */
00736 APR_DECLARE(apr_status_t) apr_file_namedpipe_create(const char *filename, 
00737                                                     apr_fileperms_t perm, 
00738                                                     apr_pool_t *pool);
00739 
00740 /**
00741  * Get the timeout value for a pipe or manipulate the blocking state.
00742  * @param thepipe The pipe we are getting a timeout for.
00743  * @param timeout The current timeout value in microseconds. 
00744  */
00745 APR_DECLARE(apr_status_t) apr_file_pipe_timeout_get(apr_file_t *thepipe, 
00746                                                apr_interval_time_t *timeout);
00747 
00748 /**
00749  * Set the timeout value for a pipe or manipulate the blocking state.
00750  * @param thepipe The pipe we are setting a timeout on.
00751  * @param timeout The timeout value in microseconds.  Values < 0 mean wait 
00752  *        forever, 0 means do not wait at all.
00753  */
00754 APR_DECLARE(apr_status_t) apr_file_pipe_timeout_set(apr_file_t *thepipe, 
00755                                                   apr_interval_time_t timeout);
00756 
00757 /** file (un)locking functions. */
00758 
00759 /**
00760  * Establish a lock on the specified, open file. The lock may be advisory
00761  * or mandatory, at the discretion of the platform. The lock applies to
00762  * the file as a whole, rather than a specific range. Locks are established
00763  * on a per-thread/process basis; a second lock by the same thread will not
00764  * block.
00765  * @param thefile The file to lock.
00766  * @param type The type of lock to establish on the file.
00767  */
00768 APR_DECLARE(apr_status_t) apr_file_lock(apr_file_t *thefile, int type);
00769 
00770 /**
00771  * Remove any outstanding locks on the file.
00772  * @param thefile The file to unlock.
00773  */
00774 APR_DECLARE(apr_status_t) apr_file_unlock(apr_file_t *thefile);
00775 
00776 /**accessor and general file_io functions. */
00777 
00778 /**
00779  * return the file name of the current file.
00780  * @param new_path The path of the file.  
00781  * @param thefile The currently open file.
00782  */                     
00783 APR_DECLARE(apr_status_t) apr_file_name_get(const char **new_path, 
00784                                             apr_file_t *thefile);
00785     
00786 /**
00787  * Return the data associated with the current file.
00788  * @param data The user data associated with the file.  
00789  * @param key The key to use for retrieving data associated with this file.
00790  * @param file The currently open file.
00791  */                     
00792 APR_DECLARE(apr_status_t) apr_file_data_get(void **data, const char *key, 
00793                                             apr_file_t *file);
00794 
00795 /**
00796  * Set the data associated with the current file.
00797  * @param file The currently open file.
00798  * @param data The user data to associate with the file.  
00799  * @param key The key to use for associating data with the file.
00800  * @param cleanup The cleanup routine to use when the file is destroyed.
00801  */                     
00802 APR_DECLARE(apr_status_t) apr_file_data_set(apr_file_t *file, void *data,
00803                                             const char *key,
00804                                             apr_status_t (*cleanup)(void *));
00805 
00806 /**
00807  * Write a string to a file using a printf format.
00808  * @param fptr The file to write to.
00809  * @param format The format string
00810  * @param ... The values to substitute in the format string
00811  * @return The number of bytes written
00812  */ 
00813 APR_DECLARE_NONSTD(int) apr_file_printf(apr_file_t *fptr, 
00814                                         const char *format, ...)
00815         __attribute__((format(printf,2,3)));
00816 
00817 /**
00818  * set the specified file's permission bits.
00819  * @param fname The file (name) to apply the permissions to.
00820  * @param perms The permission bits to apply to the file.
00821  *
00822  * @warning Some platforms may not be able to apply all of the
00823  * available permission bits; #APR_INCOMPLETE will be returned if some
00824  * permissions are specified which could not be set.
00825  *
00826  * @warning Platforms which do not implement this feature will return
00827  * #APR_ENOTIMPL.
00828  */
00829 APR_DECLARE(apr_status_t) apr_file_perms_set(const char *fname,
00830                                              apr_fileperms_t perms);
00831 
00832 /**
00833  * Set attributes of the specified file.
00834  * @param fname The full path to the file (using / on all systems)
00835  * @param attributes Or'd combination of
00836  *            @li #APR_FILE_ATTR_READONLY   - make the file readonly
00837  *            @li #APR_FILE_ATTR_EXECUTABLE - make the file executable
00838  *            @li #APR_FILE_ATTR_HIDDEN     - make the file hidden
00839  * @param attr_mask Mask of valid bits in attributes.
00840  * @param pool the pool to use.
00841  * @remark This function should be used in preference to explicit manipulation
00842  *      of the file permissions, because the operations to provide these
00843  *      attributes are platform specific and may involve more than simply
00844  *      setting permission bits.
00845  * @warning Platforms which do not implement this feature will return
00846  *      #APR_ENOTIMPL.
00847  */
00848 APR_DECLARE(apr_status_t) apr_file_attrs_set(const char *fname,
00849                                              apr_fileattrs_t attributes,
00850                                              apr_fileattrs_t attr_mask,
00851                                              apr_pool_t *pool);
00852 
00853 /**
00854  * Set the mtime of the specified file.
00855  * @param fname The full path to the file (using / on all systems)
00856  * @param mtime The mtime to apply to the file.
00857  * @param pool The pool to use.
00858  * @warning Platforms which do not implement this feature will return
00859  *      #APR_ENOTIMPL.
00860  */
00861 APR_DECLARE(apr_status_t) apr_file_mtime_set(const char *fname,
00862                                              apr_time_t mtime,
00863                                              apr_pool_t *pool);
00864 
00865 /**
00866  * Create a new directory on the file system.
00867  * @param path the path for the directory to be created. (use / on all systems)
00868  * @param perm Permissions for the new directory.
00869  * @param pool the pool to use.
00870  */                        
00871 APR_DECLARE(apr_status_t) apr_dir_make(const char *path, apr_fileperms_t perm, 
00872                                        apr_pool_t *pool);
00873 
00874 /** Creates a new directory on the file system, but behaves like
00875  * 'mkdir -p'. Creates intermediate directories as required. No error
00876  * will be reported if PATH already exists.
00877  * @param path the path for the directory to be created. (use / on all systems)
00878  * @param perm Permissions for the new directory.
00879  * @param pool the pool to use.
00880  */
00881 APR_DECLARE(apr_status_t) apr_dir_make_recursive(const char *path,
00882                                                  apr_fileperms_t perm,
00883                                                  apr_pool_t *pool);
00884 
00885 /**
00886  * Remove directory from the file system.
00887  * @param path the path for the directory to be removed. (use / on all systems)
00888  * @param pool the pool to use.
00889  * @remark Removing a directory which is in-use (e.g., the current working
00890  * directory, or during apr_dir_read, or with an open file) is not portable.
00891  */                        
00892 APR_DECLARE(apr_status_t) apr_dir_remove(const char *path, apr_pool_t *pool);
00893 
00894 /**
00895  * get the specified file's stats.
00896  * @param finfo Where to store the information about the file.
00897  * @param wanted The desired apr_finfo_t fields, as a bit flag of APR_FINFO_* values 
00898  * @param thefile The file to get information about.
00899  */ 
00900 APR_DECLARE(apr_status_t) apr_file_info_get(apr_finfo_t *finfo, 
00901                                             apr_int32_t wanted,
00902                                             apr_file_t *thefile);
00903     
00904 
00905 /**
00906  * Truncate the file's length to the specified offset
00907  * @param fp The file to truncate
00908  * @param offset The offset to truncate to.
00909  * @remark The read/write file offset is repositioned to offset.
00910  */
00911 APR_DECLARE(apr_status_t) apr_file_trunc(apr_file_t *fp, apr_off_t offset);
00912 
00913 /**
00914  * Retrieve the flags that were passed into apr_file_open()
00915  * when the file was opened.
00916  * @return apr_int32_t the flags
00917  */
00918 APR_DECLARE(apr_int32_t) apr_file_flags_get(apr_file_t *f);
00919 
00920 /**
00921  * Get the pool used by the file.
00922  */
00923 APR_POOL_DECLARE_ACCESSOR(file);
00924 
00925 /**
00926  * Set a file to be inherited by child processes.
00927  *
00928  */
00929 APR_DECLARE_INHERIT_SET(file);
00930 
00931 /**
00932  * Unset a file from being inherited by child processes.
00933  */
00934 APR_DECLARE_INHERIT_UNSET(file);
00935 
00936 /**
00937  * Open a temporary file
00938  * @param fp The apr file to use as a temporary file.
00939  * @param templ The template to use when creating a temp file.
00940  * @param flags The flags to open the file with. If this is zero,
00941  *              the file is opened with 
00942  *              #APR_FOPEN_CREATE | #APR_FOPEN_READ | #APR_FOPEN_WRITE |
00943  *              #APR_FOPEN_EXCL | #APR_FOPEN_DELONCLOSE
00944  * @param p The pool to allocate the file out of.
00945  * @remark   
00946  * This function  generates  a unique temporary file name from template.  
00947  * The last six characters of template must be XXXXXX and these are replaced 
00948  * with a string that makes the filename unique. Since it will  be  modified,
00949  * template must not be a string constant, but should be declared as a character
00950  * array.  
00951  *
00952  */
00953 APR_DECLARE(apr_status_t) apr_file_mktemp(apr_file_t **fp, char *templ,
00954                                           apr_int32_t flags, apr_pool_t *p);
00955 
00956 
00957 /**
00958  * Find an existing directory suitable as a temporary storage location.
00959  * @param temp_dir The temp directory.
00960  * @param p The pool to use for any necessary allocations.
00961  * @remark   
00962  * This function uses an algorithm to search for a directory that an
00963  * an application can use for temporary storage.
00964  *
00965  */
00966 APR_DECLARE(apr_status_t) apr_temp_dir_get(const char **temp_dir, 
00967                                            apr_pool_t *p);
00968 
00969 /** @} */
00970 
00971 #ifdef __cplusplus
00972 }
00973 #endif
00974 
00975 #endif  /* ! APR_FILE_IO_H */
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