apr_file_io.h

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 * @param thefile The file descriptor
 * @param where How to move the pointer, one of:
 * <PRE>
 *            APR_SET  --  set the offset to offset
 *            APR_CUR  --  add the offset to the current position 
 *            APR_END  --  add the offset to the current file size 
 * </PRE>
 * @param offset The offset to move the pointer to.
 * @remark The third argument is modified to be the offset the pointer
          was actually moved to.
 */
APR_DECLARE(apr_status_t) apr_file_seek(apr_file_t *thefile, 
                                   apr_seek_where_t where,
                                   apr_off_t *offset);

/**
 * Create an anonymous pipe.
 * @param in The newly created pipe's file for reading.
 * @param out The newly created pipe's file for writing.
 * @param pool The pool to operate on.
 * @remark By default, the returned file descriptors will be inherited
 * by child processes created using apr_proc_create().  This can be
 * changed using apr_file_inherit_unset().
 * @bug  Some platforms cannot toggle between blocking and nonblocking,
 * and when passing a pipe as a standard handle to an application which
 * does not expect it, a non-blocking stream will fluxor the client app.
 * @deprecated @see apr_file_pipe_create_ex
 */
APR_DECLARE(apr_status_t) apr_file_pipe_create(apr_file_t **in, 
                                               apr_file_t **out,
                                               apr_pool_t *pool);

/**
 * Create an anonymous pipe which portably supports async timeout options.
 * @param in The newly created pipe's file for reading.
 * @param out The newly created pipe's file for writing.
 * @param blocking one of these values defined in apr_thread_proc.h;
 * <pre>
 *       APR_FULL_BLOCK
 *       APR_READ_BLOCK
 *       APR_WRITE_BLOCK
 *       APR_FULL_NONBLOCK
 * </pre>
 * @remark By default, the returned file descriptors will be inherited
 * by child processes created using apr_proc_create().  This can be
 * changed using apr_file_inherit_unset().
 * @remark Some platforms cannot toggle between blocking and nonblocking,
 * and when passing a pipe as a standard handle to an application which
 * does not expect it, a non-blocking stream will fluxor the client app.
 * Use this function rather than apr_file_pipe_create to create pipes 
 * where one or both ends require non-blocking semantics.
 */
APR_DECLARE(apr_status_t) apr_file_pipe_create_ex(apr_file_t **in, 
                                                  apr_file_t **out, 
                                                  apr_int32_t blocking, 
                                                  apr_pool_t *p);

/**
 * Create a named pipe.
 * @param filename The filename of the named pipe
 * @param perm The permissions for the newly created pipe.
 * @param pool The pool to operate on.
 */
APR_DECLARE(apr_status_t) apr_file_namedpipe_create(const char *filename, 
                                                    apr_fileperms_t perm, 
                                                    apr_pool_t *pool);

/**
 * Get the timeout value for a pipe or manipulate the blocking state.
 * @param thepipe The pipe we are getting a timeout for.
 * @param timeout The current timeout value in microseconds. 
 */
APR_DECLARE(apr_status_t) apr_file_pipe_timeout_get(apr_file_t *thepipe, 
                                               apr_interval_time_t *timeout);

/**
 * Set the timeout value for a pipe or manipulate the blocking state.
 * @param thepipe The pipe we are setting a timeout on.
 * @param timeout The timeout value in microseconds.  Values < 0 mean wait 
 *        forever, 0 means do not wait at all.
 */
APR_DECLARE(apr_status_t) apr_file_pipe_timeout_set(apr_file_t *thepipe, 
                                                  apr_interval_time_t timeout);

/** file (un)locking functions. */

/**
 * Establish a lock on the specified, open file. The lock may be advisory
 * or mandatory, at the discretion of the platform. The lock applies to
 * the file as a whole, rather than a specific range. Locks are established
 * on a per-thread/process basis; a second lock by the same thread will not
 * block.
 * @param thefile The file to lock.
 * @param type The type of lock to establish on the file.
 */
APR_DECLARE(apr_status_t) apr_file_lock(apr_file_t *thefile, int type);

/**
 * Remove any outstanding locks on the file.
 * @param thefile The file to unlock.
 */
APR_DECLARE(apr_status_t) apr_file_unlock(apr_file_t *thefile);

/**accessor and general file_io functions. */

/**
 * return the file name of the current file.
 * @param new_path The path of the file.  
 * @param thefile The currently open file.
 */                     
APR_DECLARE(apr_status_t) apr_file_name_get(const char **new_path, 
                                            apr_file_t *thefile);
    
/**
 * Return the data associated with the current file.
 * @param data The user data associated with the file.  
 * @param key The key to use for retreiving data associated with this file.
 * @param file The currently open file.
 */                     
APR_DECLARE(apr_status_t) apr_file_data_get(void **data, const char *key, 
                                            apr_file_t *file);

/**
 * Set the data associated with the current file.
 * @param file The currently open file.
 * @param data The user data to associate with the file.  
 * @param key The key to use for assocaiteing data with the file.
 * @param cleanup The cleanup routine to use when the file is destroyed.
 */                     
APR_DECLARE(apr_status_t) apr_file_data_set(apr_file_t *file, void *data,
                                            const char *key,
                                            apr_status_t (*cleanup)(void *));

/**
 * Write a string to a file using a printf format.
 * @param fptr The file to write to.
 * @param format The format string
 * @param ... The values to substitute in the format string
 * @return The number of bytes written
 */ 
APR_DECLARE_NONSTD(int) apr_file_printf(apr_file_t *fptr, 
                                        const char *format, ...)
        __attribute__((format(printf,2,3)));

/**
 * set the specified file's permission bits.
 * @param fname The file (name) to apply the permissions to.
 * @param perms The permission bits to apply to the file.
 *
 * @warning Some platforms may not be able to apply all of the
 * available permission bits; APR_INCOMPLETE will be returned if some
 * permissions are specified which could not be set.
 *
 * @warning Platforms which do not implement this feature will return
 * APR_ENOTIMPL.
 */
APR_DECLARE(apr_status_t) apr_file_perms_set(const char *fname,
                                             apr_fileperms_t perms);

/**
 * Set attributes of the specified file.
 * @param fname The full path to the file (using / on all systems)
 * @param attributes Or'd combination of
 * <PRE>
 *            APR_FILE_ATTR_READONLY   - make the file readonly
 *            APR_FILE_ATTR_EXECUTABLE - make the file executable
 *            APR_FILE_ATTR_HIDDEN     - make the file hidden
 * </PRE>
 * @param attr_mask Mask of valid bits in attributes.
 * @param pool the pool to use.
 * @remark This function should be used in preference to explict manipulation
 *      of the file permissions, because the operations to provide these
 *      attributes are platform specific and may involve more than simply
 *      setting permission bits.
 * @warning Platforms which do not implement this feature will return
 *      APR_ENOTIMPL.
 */
APR_DECLARE(apr_status_t) apr_file_attrs_set(const char *fname,
                                             apr_fileattrs_t attributes,
                                             apr_fileattrs_t attr_mask,
                                             apr_pool_t *pool);

/**
 * Set the mtime of the specified file.
 * @param fname The full path to the file (using / on all systems)
 * @param mtime The mtime to apply to the file.
 * @param pool The pool to use.
 * @warning Platforms which do not implement this feature will return
 *      APR_ENOTIMPL.
 */
APR_DECLARE(apr_status_t) apr_file_mtime_set(const char *fname,
                                             apr_time_t mtime,
                                             apr_pool_t *pool);

/**
 * Create a new directory on the file system.
 * @param path the path for the directory to be created. (use / on all systems)
 * @param perm Permissions for the new direcoty.
 * @param pool the pool to use.
 */                        
APR_DECLARE(apr_status_t) apr_dir_make(const char *path, apr_fileperms_t perm, 
                                       apr_pool_t *pool);

/** Creates a new directory on the file system, but behaves like
 * 'mkdir -p'. Creates intermediate directories as required. No error
 * will be reported if PATH already exists.
 * @param path the path for the directory to be created. (use / on all systems)
 * @param perm Permissions for the new direcoty.
 * @param pool the pool to use.
 */
APR_DECLARE(apr_status_t) apr_dir_make_recursive(const char *path,
                                                 apr_fileperms_t perm,
                                                 apr_pool_t *pool);

/**
 * Remove directory from the file system.
 * @param path the path for the directory to be removed. (use / on all systems)
 * @param pool the pool to use.
 * @remark Removing a directory which is in-use (e.g., the current working
 * directory, or during apr_dir_read, or with an open file) is not portable.
 */                        
APR_DECLARE(apr_status_t) apr_dir_remove(const char *path, apr_pool_t *pool);

/**
 * get the specified file's stats.
 * @param finfo Where to store the information about the file.
 * @param wanted The desired apr_finfo_t fields, as a bit flag of APR_FINFO_ values 
 * @param thefile The file to get information about.
 */ 
APR_DECLARE(apr_status_t) apr_file_info_get(apr_finfo_t *finfo, 
                                            apr_int32_t wanted,
                                            apr_file_t *thefile);
    

/**
 * Truncate the file's length to the specified offset
 * @param fp The file to truncate
 * @param offset The offset to truncate to.
 * @remark The read/write file offset is repositioned to offset.
 */
APR_DECLARE(apr_status_t) apr_file_trunc(apr_file_t *fp, apr_off_t offset);

/**
 * Retrieve the flags that were passed into apr_file_open()
 * when the file was opened.
 * @return apr_int32_t the flags
 */
APR_DECLARE(apr_int32_t) apr_file_flags_get(apr_file_t *f);

/**
 * Get the pool used by the file.
 */
APR_POOL_DECLARE_ACCESSOR(file);

/**
 * Set a file to be inherited by child processes.
 *
 */
APR_DECLARE_INHERIT_SET(file);

/**
 * Unset a file from being inherited by child processes.
 */
APR_DECLARE_INHERIT_UNSET(file);

/**
 * Open a temporary file
 * @param fp The apr file to use as a temporary file.
 * @param templ The template to use when creating a temp file.
 * @param flags The flags to open the file with. If this is zero,
 *              the file is opened with 
 *              APR_CREATE | APR_READ | APR_WRITE | APR_EXCL | APR_DELONCLOSE
 * @param p The pool to allocate the file out of.
 * @remark   
 * This function  generates  a unique temporary file name from template.  
 * The last six characters of template must be XXXXXX and these are replaced 
 * with a string that makes the filename unique. Since it will  be  modified,
 * template must not be a string constant, but should be declared as a character
 * array.  
 *
 */
APR_DECLARE(apr_status_t) apr_file_mktemp(apr_file_t **fp, char *templ,
                                          apr_int32_t flags, apr_pool_t *p);


/**
 * Find an existing directory suitable as a temporary storage location.
 * @param temp_dir The temp directory.
 * @param p The pool to use for any necessary allocations.
 * @remark   
 * This function uses an algorithm to search for a directory that an
 * an application can use for temporary storage.  Once such a
 * directory is found, that location is cached by the library.  Thus,
 * callers only pay the cost of this algorithm once if that one time
 * is successful.
 *
 */
APR_DECLARE(apr_status_t) apr_temp_dir_get(const char **temp_dir, 
                                           apr_pool_t *p);

/** @} */

#ifdef __cplusplus
}
#endif

#endif  /* ! APR_FILE_IO_H */