incubator-nuttx/fs/romfs/fs_romfs.h

233 lines
9.6 KiB
C

/****************************************************************************
* fs/romfs/fs_romfs.h
*
* Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References: Linux/Documentation/filesystems/romfs.txt
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __FS_ROMFS_FS_ROMFS_H
#define __FS_ROMFS_FS_ROMFS_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <stdbool.h>
#include <nuttx/fs/dirent.h>
#include "inode/inode.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Volume header (multi-byte values are big-endian) */
#define ROMFS_VHDR_ROM1FS 0 /* 0-7: "-rom1fs-" */
#define ROMFS_VHDR_SIZE 8 /* 8-11: Number of accessible bytes in this fs. */
#define ROMFS_VHDR_CHKSUM 12 /* 12-15: Checksum of the first 512 bytes. */
#define ROMFS_VHDR_VOLNAME 16 /* 16-..: Zero terminated volume name, padded to
* 16 byte boundary. */
#define ROMFS_VHDR_MAGIC "-rom1fs-"
/* File header offset (multi-byte values are big-endian) */
#define ROMFS_FHDR_NEXT 0 /* 0-3: Offset of the next file header
* (zero if no more files) */
#define ROMFS_FHDR_INFO 4 /* 4-7: Info for directories/hard links/
* devices */
#define ROMFS_FHDR_SIZE 8 /* 8-11: Size of this file in bytes */
#define ROMFS_FHDR_CHKSUM 12 /* 12-15: Checksum covering the meta data,
* including the file name, and
* padding. */
#define ROMFS_FHDR_NAME 16 /* 16-..: Zero terminated volume name, padded
* to 16 byte boundary. */
/* Bits 0-3 of the rf_next offset provide mode information. These are the
* values specified in */
#define RFNEXT_MODEMASK 7 /* Bits 0-2: Mode; bit 3: Executable */
#define RFNEXT_ALLMODEMASK 15 /* Bits 0-3: All mode bits */
#define RFNEXT_OFFSETMASK (~15) /* Bits n-3: Offset to next entry */
#define RFNEXT_HARDLINK 0 /* rf_info = Link destination file header */
#define RFNEXT_DIRECTORY 1 /* rf_info = First file's header */
#define RFNEXT_FILE 2 /* rf_info = Unused, must be zero */
#define RFNEXT_SOFTLINK 3 /* rf_info = Unused, must be zero */
#define RFNEXT_BLOCKDEV 4 /* rf_info = 16/16 bits major/minor number */
#define RFNEXT_CHARDEV 5 /* rf_info = 16/16 bits major/minor number */
#define RFNEXT_SOCKET 6 /* rf_info = Unused, must be zero */
#define RFNEXT_FIFO 7 /* rf_info = Unused, must be zero */
#define RFNEXT_EXEC 8 /* Modifier of RFNEXT_DIRECTORY and RFNEXT_FILE */
#define IS_MODE(rfn,mode) ((((uint32_t)(rfn))&RFNEXT_MODEMASK)==(mode))
#define IS_HARDLINK(rfn) IS_MODE(rfn,RFNEXT_HARDLINK)
#define IS_DIRECTORY(rfn) IS_MODE(rfn,RFNEXT_DIRECTORY)
#define IS_FILE(rfn) IS_MODE(rfn,RFNEXT_FILE)
#define IS_EXECUTABLE(rfn) (((rfn) & RFNEXT_EXEC) != 0)
/* RFNEXT_SOFTLINK, RFNEXT_BLOCKDEV, RFNEXT_CHARDEV, RFNEXT_SOCKET, and
* RFNEXT_FIFO are not presently supported in NuttX.
*/
/* Alignment macros */
#define ROMFS_ALIGNMENT 16
#define ROMFS_MAXPADDING (ROMFS_ALIGNMENT-1)
#define ROMFS_ALIGNMASK (~ROMFS_MAXPADDING)
#define ROMFS_ALIGNUP(addr) ((((uint32_t)(addr))+ROMFS_MAXPADDING)&ROMFS_ALIGNMASK)
#define ROMFS_ALIGNDOWN(addr) (((uint32_t)(addr))&ROMFS_ALIGNMASK)
/* Offset and sector conversions */
#define SEC_NDXMASK(r) ((r)->rm_hwsectorsize - 1)
#define SEC_NSECTORS(r,o) ((o) / (r)->rm_hwsectorsize)
#define SEC_ALIGN(r,o) ((o) & ~SEC_NDXMASK(r))
/* Maximum numbr of links that will be followed before we decide that there
* is a problem.
*/
#define ROMF_MAX_LINKS 64
/****************************************************************************
* Public Types
****************************************************************************/
/* This structure represents the overall mountpoint state. An instance of this
* structure is retained as inode private data on each mountpoint that is
* mounted with a fat32 filesystem.
*/
struct romfs_file_s;
struct romfs_mountpt_s
{
struct inode *rm_blkdriver; /* The block driver inode that hosts the FAT32 fs */
struct romfs_file_s *rm_head; /* A list to all files opened on this mountpoint */
bool rm_mounted; /* true: The file system is ready */
uint16_t rm_hwsectorsize; /* HW: Sector size reported by block driver*/
sem_t rm_sem; /* Used to assume thread-safe access */
uint32_t rm_rootoffset; /* Saved offset to the first root directory entry */
uint32_t rm_hwnsectors; /* HW: The number of sectors reported by the hardware */
uint32_t rm_volsize; /* Size of the ROMFS volume */
uint32_t rm_cachesector; /* Current sector in the rm_buffer */
uint8_t *rm_xipbase; /* Base address of directly accessible media */
uint8_t *rm_buffer; /* Device sector buffer, allocated if rm_xipbase==0 */
};
/* This structure represents on open file under the mountpoint. An instance
* of this structure is retained as struct file specific information on each
* opened file.
*/
struct romfs_file_s
{
FAR struct romfs_file_s *rf_next; /* Retained in a singly linked list */
uint32_t rf_startoffset; /* Offset to the start of the file data */
uint32_t rf_size; /* Size of the file in bytes */
uint32_t rf_cachesector; /* Current sector in the rf_buffer */
uint8_t *rf_buffer; /* File sector buffer, allocated if rm_xipbase==0 */
uint8_t rf_type; /* File type (for fstat()) */
};
/* This structure is used internally for describing the result of
* walking a path
*/
struct romfs_dirinfo_s
{
/* These values describe the directory containing the terminal
* path component (of the terminal component itself if it is
* a directory.
*/
struct fs_romfsdir_s rd_dir; /* Describes directory. */
/* Values from the ROMFS file entry */
uint32_t rd_next; /* Offset of the next file header+flags */
uint32_t rd_size; /* Size (if file) */
};
/****************************************************************************
* Public Data
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
void romfs_semtake(FAR struct romfs_mountpt_s *rm);
void romfs_semgive(FAR struct romfs_mountpt_s *rm);
int romfs_hwread(FAR struct romfs_mountpt_s *rm, FAR uint8_t *buffer,
uint32_t sector, unsigned int nsectors);
int romfs_filecacheread(FAR struct romfs_mountpt_s *rm,
FAR struct romfs_file_s *rf, uint32_t sector);
int romfs_hwconfigure(FAR struct romfs_mountpt_s *rm);
int romfs_fsconfigure(FAR struct romfs_mountpt_s *rm);
int romfs_fileconfigure(FAR struct romfs_mountpt_s *rm,
FAR struct romfs_file_s *rf);
int romfs_checkmount(FAR struct romfs_mountpt_s *rm);
int romfs_finddirentry(FAR struct romfs_mountpt_s *rm,
FAR struct romfs_dirinfo_s *dirinfo,
FAR const char *path);
int romfs_parsedirentry(FAR struct romfs_mountpt_s *rm,
uint32_t offset, FAR uint32_t *poffset, FAR uint32_t *pnext,
FAR uint32_t *pinfo, FAR uint32_t *psize);
int romfs_parsefilename(FAR struct romfs_mountpt_s *rm, uint32_t offset,
FAR char *pname);
int romfs_datastart(FAR struct romfs_mountpt_s *rm, uint32_t offset,
FAR uint32_t *start);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __FS_ROMFS_FS_ROMFS_H */