diff options
Diffstat (limited to 'nuttx/fs/nxffs/nxffs_open.c')
| -rw-r--r-- | nuttx/fs/nxffs/nxffs_open.c | 1322 |
1 files changed, 0 insertions, 1322 deletions
diff --git a/nuttx/fs/nxffs/nxffs_open.c b/nuttx/fs/nxffs/nxffs_open.c deleted file mode 100644 index 9fa4ef2e0..000000000 --- a/nuttx/fs/nxffs/nxffs_open.c +++ /dev/null @@ -1,1322 +0,0 @@ -/**************************************************************************** - * fs/nxffs/nxffs_open.c - * - * Copyright (C) 2011, 2013 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. - * - ****************************************************************************/ - -/**************************************************************************** - * Included Files - ****************************************************************************/ - -#include <nuttx/config.h> - -#include <string.h> -#include <fcntl.h> -#include <time.h> -#include <crc32.h> -#include <assert.h> -#include <errno.h> -#include <debug.h> - -#include <nuttx/kmalloc.h> -#include <nuttx/fs/fs.h> -#include <nuttx/mtd.h> - -#include "nxffs.h" - -/**************************************************************************** - * Pre-processor Definitions - ****************************************************************************/ - -/**************************************************************************** - * Private Types - ****************************************************************************/ - -/**************************************************************************** - * Private Data - ****************************************************************************/ - -/* Since we are limited to a single file opened for writing, it makes sense - * to pre-allocate the write state structure. - */ - -#ifdef CONFIG_NXFSS_PREALLOCATED -static struct nxffs_wrfile_s g_wrfile; -#endif - -/**************************************************************************** - * Public Data - ****************************************************************************/ - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: nxffs_hdrpos - * - * Description: - * Find a valid location for the inode header. A valid location will have - * these properties: - * - * 1. It will lie in the free flash region. - * 2. It will have enough contiguous memory to hold the entire header - * (excluding the file name which may lie in the next block). - * 3. The memory at this location will be fully erased. - * - * This function will only perform the checks of 1) and 2). - * - * Input Parameters: - * volume - Describes the NXFFS volume - * wrfile - Contains the current guess for the header position. On - * successful return, this field will hold the selected header - * position. - * - * Returned Value: - * Zero is returned on success. Otherwise, a negated errno value is - * returned indicating the nature of the failure. Of special interest - * the return error of -ENOSPC which means that the FLASH volume is - * full and should be repacked. - * - * On successful return the following are also valid: - * - * wrfile->ofile.entry.hoffset - FLASH offset to candidate header position - * volume->ioblock - Read/write block number of the block containing the - * header position - * volume->iooffset - The offset in the block to the candidate header - * position. - * volume->froffset - Updated offset to the first free FLASH block. - * - ****************************************************************************/ - -static inline int nxffs_hdrpos(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_wrfile_s *wrfile) -{ - int ret; - - /* Reserve memory for the object */ - - ret = nxffs_wrreserve(volume, SIZEOF_NXFFS_INODE_HDR); - if (ret == OK) - { - /* Save the offset to the FLASH region reserved for the inode header */ - - wrfile->ofile.entry.hoffset = nxffs_iotell(volume); - } - return ret; -} - -/**************************************************************************** - * Name: nxffs_nampos - * - * Description: - * Find a valid location for the inode name. A valid location will have - * these properties: - * - * 1. It will lie in the free flash region. - * 2. It will have enough contiguous memory to hold the entire name - * 3. The memory at this location will be fully erased. - * - * This function will only perform the checks of 1) and 2). - * - * Input Parameters: - * volume - Describes the NXFFS volume - * wrfile - Contains the current guess for the name position. On - * successful return, this field will hold the selected name - * position. - * namlen - The length of the name. - * - * Returned Value: - * Zero is returned on success. Otherwise, a negated errno value is - * returned indicating the nature of the failure. Of special interest - * the return error of -ENOSPC which means that the FLASH volume is - * full and should be repacked. - * - * On successful return the following are also valid: - * - * wrfile->ofile.entry.noffset - FLASH offset to candidate name position - * volume->ioblock - Read/write block number of the block containing the - * name position - * volume->iooffset - The offset in the block to the candidate name - * position. - * volume->froffset - Updated offset to the first free FLASH block. - * - ****************************************************************************/ - -static inline int nxffs_nampos(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_wrfile_s *wrfile, - int namlen) -{ - int ret; - - /* Reserve memory for the object */ - - ret = nxffs_wrreserve(volume, namlen); - if (ret == OK) - { - /* Save the offset to the FLASH region reserved for the inode name */ - - wrfile->ofile.entry.noffset = nxffs_iotell(volume); - } - return ret; -} - -/**************************************************************************** - * Name: nxffs_hdrerased - * - * Description: - * Find a valid location for the inode header. A valid location will have - * these properties: - * - * 1. It will lie in the free flash region. - * 2. It will have enough contiguous memory to hold the entire header - * (excluding the file name which may lie in the next block). - * 3. The memory at this location will be fully erased. - * - * This function will only perform the check 3). - * - * On entry it assumes: - * - * volume->ioblock - Read/write block number of the block containing the - * header position - * volume->iooffset - The offset in the block to the candidate header - * position. - * - * Input Parameters: - * volume - Describes the NXFFS volume - * wrfile - Contains the current guess for the header position. On - * successful return, this field will hold the selected header - * position. - * - * Returned Value: - * Zero is returned on success. Otherwise, a negated errno value is - * returned indicating the nature of the failure. Of special interest - * the return error of -ENOSPC which means that the FLASH volume is - * full and should be repacked. - * - * On successful return the following are also valid: - * - * wrfile->ofile.entry.hoffset - FLASH offset to candidate header position - * volume->ioblock - Read/write block number of the block containing the - * header position - * volume->iooffset - The offset in the block to the candidate header - * position. - * volume->froffset - Updated offset to the first free FLASH block. - * - ****************************************************************************/ - -static inline int nxffs_hdrerased(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_wrfile_s *wrfile) -{ - int ret; - - /* Find a valid location to save the inode header */ - - ret = nxffs_wrverify(volume, SIZEOF_NXFFS_INODE_HDR); - if (ret == OK) - { - /* This is where we will put the header */ - - wrfile->ofile.entry.hoffset = nxffs_iotell(volume); - } - return ret; -} - -/**************************************************************************** - * Name: nxffs_namerased - * - * Description: - * Find a valid location for the inode name. A valid location will have - * these properties: - * - * 1. It will lie in the free flash region. - * 2. It will have enough contiguous memory to hold the entire name - * (excluding the file name which may lie in the next block). - * 3. The memory at this location will be fully erased. - * - * This function will only perform the check 3). - * - * On entry it assumes: - * - * volume->ioblock - Read/write block number of the block containing the - * name position - * volume->iooffset - The offset in the block to the candidate name - * position. - * - * Input Parameters: - * volume - Describes the NXFFS volume - * wrfile - Contains the current guess for the name position. On - * successful return, this field will hold the selected name - * position. - * - * Returned Value: - * Zero is returned on success. Otherwise, a negated errno value is - * returned indicating the nature of the failure. Of special interest - * the return error of -ENOSPC which means that the FLASH volume is - * full and should be repacked. - * - * On successful return the following are also valid: - * - * wrfile->ofile.entry.noffset - FLASH offset to candidate name position - * volume->ioblock - Read/write block number of the block containing the - * name position - * volume->iooffset - The offset in the block to the candidate name - * position. - * volume->froffset - Updated offset to the first free FLASH block. - * - ****************************************************************************/ - -static inline int nxffs_namerased(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_wrfile_s *wrfile, - int namlen) -{ - int ret; - - /* Find a valid location to save the inode name */ - - ret = nxffs_wrverify(volume, namlen); - if (ret == OK) - { - /* This is where we will put the name */ - - wrfile->ofile.entry.noffset = nxffs_iotell(volume); - } - return ret; -} - -/**************************************************************************** - * Name: nxffs_wrname - * - * Description: - * Write the inode name to cache at the position verified by - * nxffs_namerased(). - * - * On entry it assumes: - * - * entry->noffset - FLASH offset to final name position - * volume->ioblock - Read/write block number of the block containing the - * name position - * volume->iooffset - The offset in the block to the candidate name - * position. - * - * Input Parameters: - * volume - Describes the NXFFS volume - * entry - Describes the entry to be written. - * - * Returned Value: - * Zero is returned on success. Otherwise, a negated errno value is - * returned indicating the nature of the failure. - * - ****************************************************************************/ - -static inline int nxffs_wrname(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_entry_s *entry, - int namlen) -{ - int ret; - - /* Seek to the inode name position and assure that it is in the volume - * cache. - */ - - nxffs_ioseek(volume, entry->noffset); - ret = nxffs_rdcache(volume, volume->ioblock); - if (ret < 0) - { - fdbg("Failed to read inode name block %d: %d\n", - volume->ioblock, -ret); - return ret; - } - - /* Copy the inode name to the volume cache and write the inode name block */ - - memcpy(&volume->cache[volume->iooffset], entry->name, namlen); - ret = nxffs_wrcache(volume); - if (ret < 0) - { - fdbg("Failed to write inode header block %d: %d\n", - volume->ioblock, -ret); - } - - return ret; -} - -/**************************************************************************** - * Name: nxffs_wropen - * - * Description: - * Handle opening for writing. Only a single writer is permitted and only - * file creation is supported. - * - ****************************************************************************/ - -static inline int nxffs_wropen(FAR struct nxffs_volume_s *volume, - FAR const char *name, mode_t oflags, - FAR struct nxffs_ofile_s **ppofile) -{ - FAR struct nxffs_wrfile_s *wrfile; - FAR struct nxffs_entry_s entry; - bool packed; - bool truncate = false; - int namlen; - int ret; - - /* Limitation: Only a single writer is permitted. Writing may involve - * extension of the file system in FLASH. Since files are contiguous - * in FLASH, only a single file may be extending the FLASH region. - */ - - ret = sem_wait(&volume->wrsem); - if (ret != OK) - { - fdbg("sem_wait failed: %d\n", ret); - ret = -errno; - goto errout; - } - - /* Get exclusive access to the volume. Note that the volume exclsem - * protects the open file list. Note that exclsem is ALWAYS taken - * after wrsem to avoid deadlocks. - */ - - ret = sem_wait(&volume->exclsem); - if (ret != OK) - { - fdbg("sem_wait failed: %d\n", ret); - ret = -errno; - goto errout_with_wrsem; - } - - /* Check if the file exists */ - - ret = nxffs_findinode(volume, name, &entry); - if (ret == OK) - { - FAR struct nxffs_ofile_s *ofile; - - /* It exists. Is the file already open for reading? */ - - ofile = nxffs_findofile(volume, name); - if (ofile) - { - /* The file is already open. - * Limitation: Files cannot be open both for reading and writing. - */ - - fdbg("File is open for reading\n"); - ret = -ENOSYS; - goto errout_with_exclsem; - } - - /* It would be an error if we are asked to create the file - * exclusively. - */ - - else if ((oflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL)) - { - fdbg("File exists, can't create O_EXCL\n"); - ret = -EEXIST; - goto errout_with_exclsem; - } - - /* Were we asked to truncate the file? NOTE: Don't truncate the - * file if we were not also asked to created it. See below... - * we will not re-create the file unless O_CREAT is also specified. - */ - - else if ((oflags & (O_CREAT|O_TRUNC)) == (O_CREAT|O_TRUNC)) - { - /* Just schedule the removal the file and fall through to re-create it. - * Note that the old file of the same name will not actually be removed - * until the new file is successfully written. - */ - - truncate = true; - } - - /* The file exists and we were not asked to truncate (and recreate) it. - * Limitation: Cannot write to existing files. - */ - - else - { - fdbg("File %s exists and we were not asked to truncate it\n"); - ret = -ENOSYS; - goto errout_with_exclsem; - } - } - - /* Okay, the file is not open and does not exists (maybe because we deleted - * it). Now, make sure that we were asked to created it. - */ - - if ((oflags & O_CREAT) == 0) - { - fdbg("Not asked to create the file\n"); - ret = -ENOENT; - goto errout_with_exclsem; - } - - /* Make sure that the length of the file name will fit in a uint8_t */ - - namlen = strlen(name); - if (namlen > CONFIG_NXFFS_MAXNAMLEN) - { - fdbg("Name is too long: %d\n", namlen); - ret = -EINVAL; - goto errout_with_exclsem; - } - - /* Yes.. Create a new structure that will describe the state of this open - * file. NOTE that a special variant of the open file structure is used - * that includes additional information to support the write operation. - */ - -#ifdef CONFIG_NXFSS_PREALLOCATED - wrfile = &g_wrfile; - memset(wrfile, 0, sizeof(struct nxffs_wrfile_s)); -#else - wrfile = (FAR struct nxffs_wrfile_s *)kzalloc(sizeof(struct nxffs_wrfile_s)); - if (!wrfile) - { - ret = -ENOMEM; - goto errout_with_exclsem; - } -#endif - - /* Initialize the open file state structure */ - - wrfile->ofile.crefs = 1; - wrfile->ofile.oflags = oflags; - wrfile->ofile.entry.utc = time(NULL); - wrfile->truncate = truncate; - - /* Save a copy of the inode name. */ - - wrfile->ofile.entry.name = strdup(name); - if (!wrfile->ofile.entry.name) - { - ret = -ENOMEM; - goto errout_with_ofile; - } - - /* Allocate FLASH memory for the file and set up for the write. - * - * Loop until the inode header is configured or until a failure occurs. - * Note that nothing is written to FLASH. The inode header is not - * written until the file is closed. - */ - - packed = false; - for (;;) - { - /* File a valid location to position the inode header. Start with the - * first byte in the free FLASH region. - */ - - ret = nxffs_hdrpos(volume, wrfile); - if (ret == OK) - { - /* Find a region of memory in the block that is fully erased */ - - ret = nxffs_hdrerased(volume, wrfile); - if (ret == OK) - { - /* Valid memory for the inode header was found. Break out of - * the loop. - */ - - break; - } - } - - /* If no valid memory is found searching to the end of the volume, - * then -ENOSPC will be returned. Other errors are not handled. - */ - - if (ret != -ENOSPC || packed) - { - fdbg("Failed to find inode header memory: %d\n", -ret); - goto errout_with_name; - } - - /* -ENOSPC is a special case.. It means that the volume is full. - * Try to pack the volume in order to free up some space. - */ - - ret = nxffs_pack(volume); - if (ret < 0) - { - fdbg("Failed to pack the volume: %d\n", -ret); - goto errout_with_name; - } - - /* After packing the volume, froffset will be updated to point to the - * new free flash region. Try again. - */ - - packed = true; - } - - /* Loop until the inode name is configured or until a failure occurs. - * Note that nothing is written to FLASH. - */ - - for (;;) - { - /* File a valid location to position the inode name. Start with the - * first byte in the free FLASH region. - */ - - ret = nxffs_nampos(volume, wrfile, namlen); - if (ret == OK) - { - /* Find a region of memory in the block that is fully erased */ - - ret = nxffs_namerased(volume, wrfile, namlen); - if (ret == OK) - { - /* Valid memory for the inode header was found. Write the - * inode name to this location. - */ - - ret = nxffs_wrname(volume, &wrfile->ofile.entry, namlen); - if (ret < 0) - { - fdbg("Failed to write the inode name: %d\n", -ret); - goto errout_with_name; - } - - /* Then just break out of the loop reporting success. Note - * that the alllocated inode name string is retained; it - * will be needed later to calculate the inode CRC. - */ - - break; - } - } - - /* If no valid memory is found searching to the end of the volume, - * then -ENOSPC will be returned. Other errors are not handled. - */ - - if (ret != -ENOSPC || packed) - { - fdbg("Failed to find inode name memory: %d\n", -ret); - goto errout_with_name; - } - - /* -ENOSPC is a special case.. It means that the volume is full. - * Try to pack the volume in order to free up some space. - */ - - ret = nxffs_pack(volume); - if (ret < 0) - { - fdbg("Failed to pack the volume: %d\n", -ret); - goto errout_with_name; - } - - /* After packing the volume, froffset will be updated to point to the - * new free flash region. Try again. - */ - - packed = true; - } - - /* Add the open file structure to the head of the list of open files */ - - wrfile->ofile.flink = volume->ofiles; - volume->ofiles = &wrfile->ofile; - - /* Indicate that the volume is open for writing and return the open file - * instance. Releasing exclsem allows other readers while the write is - * in progress. But wrsem is still held for this open file, preventing - * any further writers until this inode is closed.s - */ - - *ppofile = &wrfile->ofile; - sem_post(&volume->exclsem); - return OK; - -errout_with_name: - kfree(wrfile->ofile.entry.name); -errout_with_ofile: -#ifndef CONFIG_NXFSS_PREALLOCATED - kfree(wrfile); -#endif - -errout_with_exclsem: - sem_post(&volume->exclsem); -errout_with_wrsem: - sem_post(&volume->wrsem); -errout: - return ret; -} - -/**************************************************************************** - * Name: nxffs_rdopen - * - * Description: - * Open an existing file for reading. - * - ****************************************************************************/ - -static inline int nxffs_rdopen(FAR struct nxffs_volume_s *volume, - FAR const char *name, - FAR struct nxffs_ofile_s **ppofile) -{ - FAR struct nxffs_ofile_s *ofile; - int ret; - - /* Get exclusive access to the volume. Note that the volume exclsem - * protects the open file list. - */ - - ret = sem_wait(&volume->exclsem); - if (ret != OK) - { - fdbg("sem_wait failed: %d\n", ret); - ret = -errno; - goto errout; - } - - /* Check if the file has already been opened (for reading) */ - - ofile = nxffs_findofile(volume, name); - if (ofile) - { - /* The file is already open. - * Limitation: Files cannot be open both for reading and writing. - */ - - if ((ofile->oflags & O_WROK) != 0) - { - fdbg("File is open for writing\n"); - ret = -ENOSYS; - goto errout_with_exclsem; - } - - /* Just increment the reference count on the ofile */ - - ofile->crefs++; - fdbg("crefs: %d\n", ofile->crefs); - } - - /* The file has not yet been opened. - * Limitation: The file must exist. We do not support creation of files - * read-only. - */ - - else - { - /* Not already open.. create a new open structure */ - - ofile = (FAR struct nxffs_ofile_s *)kzalloc(sizeof(struct nxffs_ofile_s)); - if (!ofile) - { - fdbg("ofile allocation failed\n"); - ret = -ENOMEM; - goto errout_with_exclsem; - } - - /* Initialize the open file state structure */ - - ofile->crefs = 1; - ofile->oflags = O_RDOK; - - /* Find the file on this volume associated with this file name */ - - ret = nxffs_findinode(volume, name, &ofile->entry); - if (ret != OK) - { - fvdbg("Inode '%s' not found: %d\n", name, -ret); - goto errout_with_ofile; - } - - /* Add the open file structure to the head of the list of open files */ - - ofile->flink = volume->ofiles; - volume->ofiles = ofile; - } - - /* Return the open file state structure */ - - *ppofile = ofile; - sem_post(&volume->exclsem); - return OK; - -errout_with_ofile: - kfree(ofile); -errout_with_exclsem: - sem_post(&volume->exclsem); -errout: - return ret; -} - -/**************************************************************************** - * Name: nxffs_remofile - * - * Description: - * Remove an entry from the open file list. - * - ****************************************************************************/ - -static inline void nxffs_remofile(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_ofile_s *ofile) -{ - FAR struct nxffs_ofile_s *prev; - FAR struct nxffs_ofile_s *curr; - - /* Find the open file structure to be removed */ - - for (prev = NULL, curr = volume->ofiles; - curr && curr != ofile; - prev = curr, curr = curr->flink); - - /* Was it found? */ - - if (curr) - { - /* Yes.. at the head of the list? */ - - if (prev) - { - prev->flink = ofile->flink; - } - else - { - volume->ofiles = ofile->flink; - } - } - else - { - fdbg("ERROR: Open inode %p not found\n", ofile); - } -} - -/**************************************************************************** - * Name: nxffs_freeofile - * - * Description: - * Free resources held by an open file. - * - ****************************************************************************/ - -static inline void nxffs_freeofile(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_ofile_s *ofile) -{ - /* Release the open file entry */ - - nxffs_freeentry(&ofile->entry); - - /* Then free the open file container (unless this the pre-alloated - * write-only open file container) - */ - -#ifdef CONFIG_NXFSS_PREALLOCATED - if ((FAR struct nxffs_wrfile_s*)ofile != &g_wrfile) -#endif - { - kfree(ofile); - } -} - -/**************************************************************************** - * Name: nxffs_wrclose - * - * Description: - * Perform special operations when a file is closed: - * 1. Write the file block header - * 2. Remove any file with the same name that was discovered when the - * file was open for writing, and finally, - * 3. Write the new file inode. - * - * Input parameters - * volume - Describes the NXFFS volume - * wrfile - Describes the state of the open file - * - ****************************************************************************/ - -static inline int nxffs_wrclose(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_wrfile_s *wrfile) -{ - int ret; - - /* Is there an unfinalized write data? */ - - if (wrfile->datlen > 0) - { - /* Yes.. Write the final file block header */ - - ret = nxffs_wrblkhdr(volume, wrfile); - if (ret < 0) - { - fdbg("Failed to write the final block of the file: %d\n", -ret); - goto errout; - } - } - - /* Truncation is implemented by writing the new file, then deleting the - * older version of the file. Note that we removed the entry from the - * open file list earlier in the close sequence; this will prevent the - * open file check from failing when we remove the old version of the - * file. - */ - - if (wrfile->truncate && wrfile->ofile.entry.name) - { - fvdbg("Removing old file: %s\n", wrfile->ofile.entry.name); - - ret = nxffs_rminode(volume, wrfile->ofile.entry.name); - if (ret < 0) - { - fdbg("nxffs_rminode failed: %d\n", -ret); - goto errout; - } - } - - /* Write the inode header to FLASH */ - - ret = nxffs_wrinode(volume, &wrfile->ofile.entry); - - /* The volume is now available for other writers */ - -errout: - sem_post(&volume->wrsem); - return ret; -} - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Name: nxffs_findofile - * - * Description: - * Search the list of already opened files to see if the inode of this - * name is one of the opened files. - * - * Input Parameters: - * name - The name of the inode to check. - * - * Returned Value: - * If an inode of this name is found in the list of opened inodes, then - * a reference to the open file structure is returned. NULL is returned - * otherwise. - * - ****************************************************************************/ - -FAR struct nxffs_ofile_s *nxffs_findofile(FAR struct nxffs_volume_s *volume, - FAR const char *name) -{ - FAR struct nxffs_ofile_s *ofile; - - /* Check every open file. Note that the volume exclsem protects the - * list of open files. - */ - - for (ofile = volume->ofiles; ofile; ofile = ofile->flink) - { - /* Check for a name match */ - - if (strcmp(name, ofile->entry.name) == 0) - { - return ofile; - } - } - - return NULL; -} - -/**************************************************************************** - * Name: nxffs_findwriter - * - * Description: - * Search the list of already opened files and return the open file - * instance for the write. - * - * Input Parameters: - * volume - Describes the NXFFS volume. - * - * Returned Value: - * If there is an active writer of the volume, its open file instance is - * returned. NULL is returned otherwise. - * - ****************************************************************************/ - -FAR struct nxffs_wrfile_s *nxffs_findwriter(FAR struct nxffs_volume_s *volume) -{ - /* We can tell if the write is in-use because it will have an allocated - * name attached. - */ - -#ifdef CONFIG_NXFSS_PREALLOCATED - return g_wrfile.ofile.entry.name != NULL ? &g_wrfile : NULL; -#else -# error "Missing implementation" -#endif -} - -/**************************************************************************** - * Name: nxffs_open - * - * Description: - * This is the standard mountpoint open method. - * - ****************************************************************************/ - -int nxffs_open(FAR struct file *filep, FAR const char *relpath, - int oflags, mode_t mode) -{ - FAR struct nxffs_volume_s *volume; - FAR struct nxffs_ofile_s *ofile = NULL; - int ret; - - fvdbg("Open '%s'\n", relpath); - - /* Sanity checks */ - - DEBUGASSERT(filep->f_priv == NULL && filep->f_inode != NULL); - - /* Get the mountpoint private data from the NuttX inode reference in the - * file structure - */ - - volume = (FAR struct nxffs_volume_s*)filep->f_inode->i_private; - DEBUGASSERT(volume != NULL); - -#ifdef CONFIG_FILE_MODE -# warning "Missing check for privileges based on inode->i_mode" -#endif - - /* Limitation: A file must be opened for reading or writing, but not both. - * There is no general way of extending the size of a file. Extending the - * file size of possible if the file to be extended is the last in the - * sequence on FLASH, but since that case is not the general case, no file - * extension is supported. - */ - - switch (oflags & (O_WROK|O_RDOK)) - { - case 0: - default: - fdbg("One of O_WRONLY/O_RDONLY must be provided\n"); - return -EINVAL; - - case O_WROK: - ret = nxffs_wropen(volume, relpath, oflags, &ofile); - break; - - case O_RDOK: - ret = nxffs_rdopen(volume, relpath, &ofile); - break; - - case O_WROK|O_RDOK: - fdbg("O_RDWR is not supported\n"); - return -ENOSYS; - } - - /* Save the reference to the open-specific state in filep->f_priv */ - - if (ret == OK) - { - filep->f_priv = ofile; - } - return ret; -} - -/**************************************************************************** - * Name: binfs_dup - * - * Description: - * Duplicate open file data in the new file structure. - * - ****************************************************************************/ - -int nxffs_dup(FAR const struct file *oldp, FAR struct file *newp) -{ -#ifdef CONFIG_DEBUG - FAR struct nxffs_volume_s *volume; -#endif - FAR struct nxffs_ofile_s *ofile; - - fvdbg("Dup %p->%p\n", oldp, newp); - - /* Sanity checks */ - -#ifdef CONFIG_DEBUG - DEBUGASSERT(oldp->f_priv == NULL && oldp->f_inode != NULL); - - /* Get the mountpoint private data from the NuttX inode reference in the - * file structure - */ - - volume = (FAR struct nxffs_volume_s*)oldp->f_inode->i_private; - DEBUGASSERT(volume != NULL); -#endif - - /* Recover the open file state from the struct file instance */ - - ofile = (FAR struct nxffs_ofile_s *)oldp->f_priv; - - /* I do not think we need exclusive access to the volume to do this. - * The volume exclsem protects the open file list and, hence, would - * assure that the ofile is stable. However, it is assumed that the - * caller holds a value file descriptor associated with this ofile, - * so it should be stable throughout the life of this function. - */ - - /* Limitations: I do not think we have to be concerned about the - * usual NXFFS file limitations here: dup'ing cannot resulting - * in mixed reading and writing to the same file, or multiple - * writer to different file. - * - * I notice that nxffs_wropen will prohibit multiple opens for - * writing. But I do not thing that dup'ing a file already opened - * for writing suffers from any of these issues. - */ - - /* Just increment the reference count on the ofile */ - - ofile->crefs++; - newp->f_priv = (FAR void *)ofile; - return OK; -} - -/**************************************************************************** - * Name: nxffs_close - * - * Description: - * This is the standard mountpoint close method. - * - ****************************************************************************/ - -int nxffs_close(FAR struct file *filep) -{ - FAR struct nxffs_volume_s *volume; - FAR struct nxffs_ofile_s *ofile; - int ret = -ENOSYS; - - fvdbg("Closing\n"); - - /* Sanity checks */ - - DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL); - - /* Recover the open file state from the struct file instance */ - - ofile = (FAR struct nxffs_ofile_s *)filep->f_priv; - - /* Recover the volume state from the open file */ - - volume = (FAR struct nxffs_volume_s *)filep->f_inode->i_private; - DEBUGASSERT(volume != NULL); - - /* Get exclusive access to the volume. Note that the volume exclsem - * protects the open file list. - */ - - ret = sem_wait(&volume->exclsem); - if (ret != OK) - { - ret = -errno; - fdbg("sem_wait failed: %d\n", ret); - goto errout; - } - - /* Decrement the reference count on the open file */ - - ret = OK; - if (ofile->crefs == 1) - { - /* Decrementing the reference count would take it zero. - * - * Remove the entry from the open file list. We do this early - * to avoid some chick-and-egg problems with file truncation. - */ - - nxffs_remofile(volume, ofile); - - /* Handle special finalization of the write operation. */ - - if ((ofile->oflags & O_WROK) != 0) - { - ret = nxffs_wrclose(volume, (FAR struct nxffs_wrfile_s *)ofile); - } - - /* Release all resouces held by the open file */ - - nxffs_freeofile(volume, ofile); - } - else - { - /* Just decrement the reference count */ - - ofile->crefs--; - } - - - filep->f_priv = NULL; - sem_post(&volume->exclsem); - -errout: - return ret; -} - -/**************************************************************************** - * Name: nxffs_wrinode - * - * Description: - * Write the inode header (only to FLASH. This is done in two contexts: - * - * 1. When an inode is closed, or - * 2. As part of the file system packing logic when an inode is moved. - * - * Note that in either case, the inode name has already been written to - * FLASH. - * - * Input parameters - * volume - Describes the NXFFS volume - * entry - Describes the inode header to write - * - * Returned Value: - * Zero is returned on success; Otherwise, a negated errno value is returned - * indicating the nature of the failure. - * - ****************************************************************************/ - -int nxffs_wrinode(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_entry_s *entry) -{ - FAR struct nxffs_inode_s *inode; - uint32_t crc; - int namlen; - int ret; - - /* Seek to the inode header position and assure that it is in the volume - * cache. - */ - - nxffs_ioseek(volume, entry->hoffset); - ret = nxffs_rdcache(volume, volume->ioblock); - if (ret < 0) - { - fdbg("Failed to read inode header block %d: %d\n", - volume->ioblock, -ret); - goto errout; - } - - /* Get the length of the inode name */ - - namlen = strlen(entry->name); - DEBUGASSERT(namlen < CONFIG_NXFFS_MAXNAMLEN); /* This was verified earlier */ - - /* Initialize the inode header */ - - inode = (FAR struct nxffs_inode_s *)&volume->cache[volume->iooffset]; - memcpy(inode->magic, g_inodemagic, NXFFS_MAGICSIZE); - - inode->state = CONFIG_NXFFS_ERASEDSTATE; - inode->namlen = namlen; - - nxffs_wrle32(inode->noffs, entry->noffset); - nxffs_wrle32(inode->doffs, entry->doffset); - nxffs_wrle32(inode->utc, entry->utc); - nxffs_wrle32(inode->crc, 0); - nxffs_wrle32(inode->datlen, entry->datlen); - - /* Calculate the CRC */ - - crc = crc32((FAR const uint8_t *)inode, SIZEOF_NXFFS_INODE_HDR); - crc = crc32part((FAR const uint8_t *)entry->name, namlen, crc); - - /* Finish the inode header */ - - inode->state = INODE_STATE_FILE; - nxffs_wrle32(inode->crc, crc); - - /* Write the block with the inode header */ - - ret = nxffs_wrcache(volume); - if (ret < 0) - { - fdbg("Failed to write inode header block %d: %d\n", - volume->ioblock, -ret); - } - - /* The volume is now available for other writers */ - -errout: - sem_post(&volume->wrsem); - return ret; -} - -/**************************************************************************** - * Name: nxffs_updateinode - * - * Description: - * The packing logic has moved an inode. Check if any open files are using - * this inode and, if so, move the data in the open file structure as well. - * - * Input parameters - * volume - Describes the NXFFS volume - * entry - Describes the new inode entry - * - * Returned Value: - * Zero is returned on success; Otherwise, a negated errno value is returned - * indicating the nature of the failure. - * - ****************************************************************************/ - -int nxffs_updateinode(FAR struct nxffs_volume_s *volume, - FAR struct nxffs_entry_s *entry) -{ - FAR struct nxffs_ofile_s *ofile; - - /* Find the open inode structure matching this name */ - - ofile = nxffs_findofile(volume, entry->name); - if (ofile) - { - /* Yes.. the file is open. Update the FLASH offsets to inode headers */ - - ofile->entry.hoffset = entry->hoffset; - ofile->entry.noffset = entry->noffset; - ofile->entry.doffset = entry->doffset; - } - return OK; -} - |