/* $Id: file_io.h 1073 2007-03-16 08:56:05Z bennylp $ *//*  * Copyright (C)2003-2007 Benny Prijono <benny@prijono.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA  */#ifndef __PJ_FILE_IO_H__#define __PJ_FILE_IO_H__/** * @file file_io.h * @brief Simple file I/O abstraction. */#include <pj/types.h>PJ_BEGIN_DECL /** * @defgroup PJ_FILE_IO File I/O * @ingroup PJ_IO * @{ * * This file contains functionalities to perform file I/O. The file * I/O can be implemented with various back-end, either using native * file API or ANSI stream.  * * @section pj_file_size_limit_sec Size Limits * * There may be limitation on the size that can be handled by the * #pj_file_setpos() or #pj_file_getpos() functions. The API itself * uses 64-bit integer for the file offset/position (where available);  * however some backends (such as ANSI) may only support signed 32-bit  * offset resolution. * * Reading and writing operation uses signed 32-bit integer to indicate * the size. * * *//** * These enumerations are used when opening file. Values PJ_O_RDONLY, * PJ_O_WRONLY, and PJ_O_RDWR are mutually exclusive. Value PJ_O_APPEND * can only be used when the file is opened for writing.  */enum pj_file_access{    PJ_O_RDONLY     = 0x1101,   /**< Open file for reading.             */    PJ_O_WRONLY     = 0x1102,   /**< Open file for writing.             */    PJ_O_RDWR       = 0x1103,   /**< Open file for reading and writing.                                      File will be truncated.            */    PJ_O_APPEND     = 0x1108    /**< Append to existing file.           */};/** * The seek directive when setting the file position with #pj_file_setpos. */enum pj_file_seek_type{    PJ_SEEK_SET     = 0x1201,   /**< Offset from beginning of the file. */    PJ_SEEK_CUR     = 0x1202,   /**< Offset from current position.      */    PJ_SEEK_END     = 0x1203    /**< Size of the file plus offset.      */};/** * Open the file as specified in \c pathname with the specified * mode, and return the handle in \c fd. All files will be opened * as binary. * * @param pool          Pool to allocate memory for the new file descriptor. * @param pathname      The file name to open. * @param flags         Open flags, which is bitmask combination of *                      #pj_file_access enum. The flag must be either *                      PJ_O_RDONLY, PJ_O_WRONLY, or PJ_O_RDWR. When file *                      writing is specified, existing file will be  *                      truncated unless PJ_O_APPEND is specified. * @param fd            The returned descriptor. * * @return              PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_open(pj_pool_t *pool,                                  const char *pathname,                                   unsigned flags,                                  pj_oshandle_t *fd);/** * Close an opened file descriptor. * * @param fd            The file descriptor. * * @return              PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_close(pj_oshandle_t fd);/** * Write data with the specified size to an opened file. * * @param fd            The file descriptor. * @param data          Data to be written to the file. * @param size          On input, specifies the size of data to be written. *                      On return, it contains the number of data actually *                      written to the file. * * @return              PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_write(pj_oshandle_t fd,                                   const void *data,                                   pj_ssize_t *size);/** * Read data from the specified file. When end-of-file condition is set, * this function will return PJ_SUCCESS but the size will contain zero. * * @param fd            The file descriptor. * @param data          Pointer to buffer to receive the data. * @param size          On input, specifies the maximum number of data to *                      read from the file. On output, it contains the size *                      of data actually read from the file. It will contain *                      zero when EOF occurs. * * @return              PJ_SUCCESS or the appropriate error code on error. *                      When EOF occurs, the return is PJ_SUCCESS but size *                      will report zero. */PJ_DECL(pj_status_t) pj_file_read(pj_oshandle_t fd,                                  void *data,                                  pj_ssize_t *size);/** * Set file position to new offset according to directive \c whence. * * @param fd            The file descriptor. * @param offset        The new file position to set. * @param whence        The directive. * * @return              PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_setpos(pj_oshandle_t fd,                                    pj_off_t offset,                                    enum pj_file_seek_type whence);/** * Get current file position. * * @param fd            The file descriptor. * @param pos           On return contains the file position as measured *                      from the beginning of the file. * * @return              PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_getpos(pj_oshandle_t fd,                                    pj_off_t *pos);/** * Flush file buffers. * * @param fd		The file descriptor. * * @return		PJ_SUCCESS or the appropriate error code on error. */PJ_DECL(pj_status_t) pj_file_flush(pj_oshandle_t fd);/** @} */PJ_END_DECL#endif  /* __PJ_FILE_IO_H__ */