/**************************************************************************** * nutts/fs.h * * Copyright (C) 2007 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 Gregory Nutt 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 __NUTTX_FS_H #define __NUTTX_FS_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include /**************************************************************************** * Definitions ****************************************************************************/ /**************************************************************************** * Type Definitions ****************************************************************************/ /* This structure is provided by devices when they are registered with the * system. It is used to call back to perform device specific operations. */ struct file; struct file_operations { /* The device driver open method differs from the mountpoint open method */ int (*open)(FAR struct file *filp); /* The following methods must be identical in signature and position because * the struct file_operations and struct mountp_operations are treated like * unions. */ int (*close)(FAR struct file *filp); ssize_t (*read)(FAR struct file *filp, char *buffer, size_t buflen); ssize_t (*write)(FAR struct file *filp, const char *buffer, size_t buflen); off_t (*seek)(FAR struct file *filp, off_t offset, int whence); int (*ioctl)(FAR struct file *filp, int cmd, unsigned long arg); /* The two structures need not be common after this point */ }; /* This structure provides information about the state of a block driver */ #ifndef CONFIG_DISABLE_MOUNTPOUNT struct geometry { boolean geo_available; /* TRUE: The device is vailable */ boolean geo_mediachanged; /* TRUE: The media has changed since last query */ boolean geo_writeenabled; /* TRUE: It is okay to write to this device */ size_t geo_nsectors; /* Number of sectors on the device */ size_t geo_sectorsize; /* Size of one sector */ }; /* This structure is provided by block devices when they register with the * system. It is used by file systems to perform filesystem transfers. It * differs from the normal driver vtable in several ways -- most notably in * that it deals in struct inode vs. struct filep. */ struct inode; struct block_operations { int (*open)(FAR struct inode *inode); int (*close)(FAR struct inode *inode); ssize_t (*read)(FAR struct inode *inode, unsigned char *buffer, size_t start_sector, unsigned int nsectors); ssize_t (*write)(FAR struct inode *inode, const unsigned char *buffer, size_t start_sector, unsigned int nsectors); int (*geometry)(FAR struct inode *inode, struct geometry *geometry); int (*ioctl)(FAR struct inode *inode, int cmd, unsigned long arg); }; /* This structure is provided by a filesystem to describe a mount point. * Note that this structure differs from file_operations ONLY in the form of * the open method. Once the file is opened, it can be accessed either as a * struct file_operations or struct mountpt_operations */ struct inode; struct internal_dir_s; struct stat; struct statfs; struct mountpt_operations { /* The mountpoint open method differs from the driver open method * because it receives (1) the inode that contains the mountpoint * private data, (2) the relative path into the mountpoint, and (3) * information to manage privileges. */ int (*open)(FAR struct file *filp, const char *relpath, int oflags, mode_t mode); /* The following methods must be identical in signature and position because * the struct file_operations and struct mountp_operations are treated like * unions. */ int (*close)(FAR struct file *filp); ssize_t (*read)(FAR struct file *filp, char *buffer, size_t buflen); ssize_t (*write)(FAR struct file *filp, const char *buffer, size_t buflen); off_t (*seek)(FAR struct file *filp, off_t offset, int whence); int (*ioctl)(FAR struct file *filp, int cmd, unsigned long arg); /* The two structures need not be common after this point. The following * are extended methods needed to deal with the unique needs of mounted * file systems. * * Additional open-file-specific mountpoint operations: */ int (*sync)(FAR struct file *filp); /* Directory operations */ int (*opendir)(struct inode *mountpt, const char *relpath, struct internal_dir_s *dir); int (*closedir)(struct inode *mountpt, struct internal_dir_s *dir); int (*readdir)(struct inode *mountpt, struct internal_dir_s *dir); int (*rewinddir)(struct inode *mountpt, struct internal_dir_s *dir); /* General volume-related mountpoint operations: */ int (*bind)(FAR struct inode *blkdriver, const void *data, void **handle); int (*unbind)(void *handle, FAR struct inode **blkdriver); int (*statfs)(struct inode *mountpt, struct statfs *buf); /* Operations on pathes */ int (*unlink)(struct inode *mountpt, const char *relpath); int (*mkdir)(struct inode *mountpt, const char *relpath, mode_t mode); int (*rmdir)(struct inode *mountpt, const char *relpath); int (*rename)(struct inode *mountpt, const char *oldrelpath, const char *newrelpath); int (*stat)(struct inode *mountpt, const char *relpath, struct stat *buf); /* NOTE: More operations will be needed here to support: disk usage stats * file stat(), file attributes, file truncation, etc. */ }; #endif /* CONFIG_DISABLE_MOUNTPOUNT */ /* This structure represents one inode in the Nuttx psuedo-file system */ struct inode { FAR struct inode *i_peer; /* Pointer to same level inode */ FAR struct inode *i_child; /* Pointer to lower level inode */ sint16 i_crefs; /* References to inode */ uint16 i_flags; /* flags for inode */ union { const struct file_operations *i_ops; /* Driver operations for inode */ #ifndef CONFIG_DISABLE_MOUNTPOUNT const struct block_operations *i_bops; /* Block driver operations */ const struct mountpt_operations *i_mops; /* Operations on a mountpoint */ #endif } u; #ifdef CONFIG_FILE_MODE mode_t i_mode; /* Access mode flags */ #endif FAR void *i_private; /* Per inode driver private data */ char i_name[1]; /* Name of inode (variable) */ }; #define FSNODE_SIZE(n) (sizeof(struct inode) + (n)) /* This is the underlying representation of an open file. A file * descriptor is an index into an array of such types. The type associates * the file descriptor to the file state and to a set of inode operations. */ struct file { int f_oflags; /* Open mode flags */ off_t f_pos; /* File position */ FAR struct inode *f_inode; /* Driver interface */ void *f_priv; /* Per file driver private data */ }; /* This defines a list of files indexed by the file descriptor */ #if CONFIG_NFILE_DESCRIPTORS > 0 struct filelist { sem_t fl_sem; /* Manage access to the file list */ sint16 fl_crefs; /* Reference count */ struct file fl_files[CONFIG_NFILE_DESCRIPTORS]; }; #endif /* This defines the list of files used for standard C I/O * We can support the standard C APIs without or without buffering */ /* Buffered file I/O structure */ #if CONFIG_NFILE_STREAMS > 0 struct file_struct { int fs_filedes; /* File descriptor associated with stream */ mode_t fs_oflags; /* Open mode flags */ #if CONFIG_NUNGET_CHARS > 0 uint8 fs_nungotten; /* The number of characters buffered for ungetc */ unsigned char fs_ungotten[CONFIG_NUNGET_CHARS]; #endif #if CONFIG_STDIO_BUFFER_SIZE > 0 sem_t fs_sem; /* For thread safety */ pid_t fs_holder; /* Holder of sem */ int fs_counts; /* Number of times sem is held */ FAR unsigned char *fs_bufstart; /* Pointer to start of buffer */ FAR unsigned char *fs_bufend; /* Pointer to 1 past end of buffer */ FAR unsigned char *fs_bufpos; /* Current position in buffer */ FAR unsigned char *fs_bufread; /* Pointer to 1 past last buffered read char. */ #endif }; struct streamlist { int sl_crefs; /* Reference count */ sem_t sl_sem; /* For thread safety */ struct file_struct sl_streams[CONFIG_NFILE_STREAMS]; }; #endif /* CONFIG_NFILE_STREAMS */ /**************************************************************************** * Global Function Prototypes ****************************************************************************/ #undef EXTERN #if defined(__cplusplus) #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /* fs_inode.c ***************************************************************/ /* These interfaces are used by drivers to register their * inodes in the inode tree. */ EXTERN void weak_function fs_initialize(void); /* fs_registerdriver.c ******************************************************/ EXTERN STATUS register_driver(const char *path, const struct file_operations *fops, mode_t mode, void *private); /* fs_registerdriver.c ******************************************************/ EXTERN STATUS register_blockdriver(const char *path, const struct block_operations *bops, mode_t mode, void *private); /* fs_unregisterdriver.c ****************************************************/ EXTERN STATUS unregister_driver(const char *path); /* fs_unregisterblockdriver.c ***********************************************/ EXTERN STATUS unregister_blockdriver(const char *path); /* fs_open.c ****************************************************************/ EXTERN int inode_checkflags(FAR struct inode *inode, int oflags); /* fs_files.c ***************************************************************/ #if CONFIG_NFILE_DESCRIPTORS >0 EXTERN FAR struct filelist *files_alloclist(void); EXTERN int files_addreflist(FAR struct filelist *list); EXTERN int files_releaselist(FAR struct filelist *list); EXTERN int files_dup(FAR struct file *filep1, FAR struct file *filep2); #endif /* lib_fopen.c **************************************************************/ /* Used by the OS to clone stdin, stdout, stderr */ #if CONFIG_NFILE_STREAMS > 0 EXTERN FAR struct file_struct *lib_fdopen(int fd, const char *mode, FAR struct filelist *flist, FAR struct streamlist *slist); #endif /* lib_fflush.c *************************************************************/ #if CONFIG_NFILE_STREAMS > 0 EXTERN void lib_flushall(FAR struct streamlist *list); #endif /* drivers ******************************************************************/ /* Call in of these to register the corresponding default * default drivers in the drivers/ subdirectory */ EXTERN void devnull_register(void); #undef EXTERN #if defined(__cplusplus) } #endif #endif /* __NUTTX_FS_H */