| /* Arduino FAT16 Library | |
| * Copyright (C) 2008 by William Greiman | |
| * | |
| * This file is part of the Arduino FAT16 Library | |
| * | |
| * This Library 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 3 of the License, or | |
| * (at your option) any later version. | |
| * | |
| * This Library 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 the Arduino Fat16 Library. If not, see | |
| * <http://www.gnu.org/licenses/>. | |
| */ | |
| //----------------------------------------------------------------------------- | |
| // volume info | |
| uint8_t Fat16::volumeInitialized_ = 0; // true if FAT16 volume is valid | |
| uint8_t Fat16::fatCount_; // number of file allocation tables | |
| uint8_t Fat16::blocksPerCluster_; // must be power of 2 | |
| uint16_t Fat16::rootDirEntryCount_; // should be 512 for FAT16 | |
| fat_t Fat16::blocksPerFat_; // number of blocks in one FAT | |
| fat_t Fat16::clusterCount_; // total clusters in volume | |
| uint32_t Fat16::fatStartBlock_; // start of first FAT | |
| uint32_t Fat16::rootDirStartBlock_; // start of root dir | |
| uint32_t Fat16::dataStartBlock_; // start of data clusters | |
| //------------------------------------------------------------------------------ | |
| // raw block cache | |
| SdCard *Fat16::rawDev_ = 0; // class for block read and write | |
| uint32_t Fat16::cacheBlockNumber_ = 0XFFFFFFFF; // init to invalid block number | |
| cache16_t Fat16::cacheBuffer_; // 512 byte cache for SdCard | |
| uint8_t Fat16::cacheDirty_ = 0; // cacheFlush() will write block if true | |
| uint32_t Fat16::cacheMirrorBlock_ = 0; // mirror block for second FAT | |
| //------------------------------------------------------------------------------ | |
| // callback function for date/time | |
| void (*Fat16::dateTime_)(uint16_t* date, uint16_t* time) = NULL; | |
| void (*Fat16::oldDateTime_)(uint16_t& date, uint16_t& time) = NULL; // NOLINT | |
| //------------------------------------------------------------------------------ | |
| // format 8.3 name for directory entry | |
| static uint8_t make83Name(const char* str, uint8_t* name) { | |
| uint8_t c; | |
| uint8_t n = 7; // max index for part before dot | |
| uint8_t i = 0; | |
| // blank fill name and extension | |
| while (i < 11) name[i++] = ' '; | |
| i = 0; | |
| while ((c = *str++) != '\0') { | |
| if (c == '.') { | |
| if (n == 10) return false; // only one dot allowed | |
| n = 10; // max index for full 8.3 name | |
| i = 8; // place for extension | |
| } else { | |
| // illegal FAT characters | |
| PGM_P p = PSTR("|<>^+=?/[];,*\"\\"); | |
| uint8_t b; | |
| while ((b = pgm_read_byte(p++))) if (b == c) return false; | |
| // check length and only allow ASCII printable characters | |
| if (i > n || c < 0X21 || c > 0X7E) return false; | |
| // only upper case allowed in 8.3 names - convert lower to upper | |
| name[i++] = c < 'a' || c > 'z' ? c : c + ('A' - 'a'); | |
| } | |
| } | |
| // must have a file name, extension is optional | |
| return name[0] != ' '; | |
| } | |
| //============================================================================== | |
| // Fat16 member functions | |
| //------------------------------------------------------------------------------ | |
| uint8_t Fat16::addCluster(void) { | |
| // start search after last cluster of file or at cluster two in FAT | |
| fat_t freeCluster = curCluster_ ? curCluster_ : 1; | |
| for (fat_t i = 0; ; i++) { | |
| // return no free clusters | |
| if (i >= clusterCount_) return false; | |
| // Fat has clusterCount + 2 entries | |
| if (freeCluster > clusterCount_) freeCluster = 1; | |
| freeCluster++; | |
| fat_t value; | |
| if (!fatGet(freeCluster, &value)) return false; | |
| if (value == 0) break; | |
| } | |
| // mark cluster allocated | |
| if (!fatPut(freeCluster, FAT16EOC)) return false; | |
| if (curCluster_ != 0) { | |
| // link cluster to chain | |
| if (!fatPut(curCluster_, freeCluster)) return false; | |
| } else { | |
| // first cluster of file so update directory entry | |
| flags_ |= F_FILE_DIR_DIRTY; | |
| firstCluster_ = freeCluster; | |
| } | |
| curCluster_ = freeCluster; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| // | |
| dir_t* Fat16::cacheDirEntry(uint16_t index, uint8_t action) { | |
| if (index >= rootDirEntryCount_) return NULL; | |
| if (!cacheRawBlock(rootDirStartBlock_ + (index >> 4), action)) return NULL; | |
| return &cacheBuffer_.dir[index & 0XF]; | |
| } | |
| //------------------------------------------------------------------------------ | |
| // | |
| uint8_t Fat16::cacheFlush(void) { | |
| if (cacheDirty_) { | |
| if (!rawDev_->writeBlock(cacheBlockNumber_, cacheBuffer_.data)) { | |
| return false; | |
| } | |
| // mirror FAT tables | |
| if (cacheMirrorBlock_) { | |
| if (!rawDev_->writeBlock(cacheMirrorBlock_, cacheBuffer_.data)) { | |
| return false; | |
| } | |
| cacheMirrorBlock_ = 0; | |
| } | |
| cacheDirty_ = 0; | |
| } | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| // | |
| uint8_t Fat16::cacheRawBlock(uint32_t blockNumber, uint8_t action) { | |
| if (cacheBlockNumber_ != blockNumber) { | |
| if (!cacheFlush()) return false; | |
| if (!rawDev_->readBlock(blockNumber, cacheBuffer_.data)) return false; | |
| cacheBlockNumber_ = blockNumber; | |
| } | |
| cacheDirty_ |= action; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Close a file and force cached data and directory information | |
| * to be written to the storage device. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include no file is open or an I/O error. | |
| */ | |
| uint8_t Fat16::close(void) { | |
| if (!sync()) return false; | |
| flags_ = 0; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Return a files directory entry | |
| * | |
| * \param[out] dir Location for return of the files directory entry. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| */ | |
| uint8_t Fat16::dirEntry(dir_t* dir) { | |
| if (!sync()) return false; | |
| dir_t* p = cacheDirEntry(dirEntryIndex_, CACHE_FOR_WRITE); | |
| if (!p) return false; | |
| memcpy(dir, p, sizeof(dir_t)); | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| uint8_t Fat16::fatGet(fat_t cluster, fat_t* value) { | |
| if (cluster > (clusterCount_ + 1)) return false; | |
| uint32_t lba = fatStartBlock_ + (cluster >> 8); | |
| if (lba != cacheBlockNumber_) { | |
| if (!cacheRawBlock(lba)) return false; | |
| } | |
| *value = cacheBuffer_.fat[cluster & 0XFF]; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| uint8_t Fat16::fatPut(fat_t cluster, fat_t value) { | |
| if (cluster < 2) return false; | |
| if (cluster > (clusterCount_ + 1)) return false; | |
| uint32_t lba = fatStartBlock_ + (cluster >> 8); | |
| if (lba != cacheBlockNumber_) { | |
| if (!cacheRawBlock(lba)) return false; | |
| } | |
| cacheBuffer_.fat[cluster & 0XFF] = value; | |
| cacheSetDirty(); | |
| // mirror second FAT | |
| if (fatCount_ > 1) cacheMirrorBlock_ = lba + blocksPerFat_; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| // free a cluster chain | |
| uint8_t Fat16::freeChain(fat_t cluster) { | |
| while (1) { | |
| fat_t next; | |
| if (!fatGet(cluster, &next)) return false; | |
| if (!fatPut(cluster, 0)) return false; | |
| if (isEOC(next)) return true; | |
| cluster = next; | |
| } | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Initialize a FAT16 volume. | |
| * | |
| * \param[in] dev The SdCard where the volume is located. | |
| * | |
| * \param[in] part The partition to be used. Legal values for \a part are | |
| * 1-4 to use the corresponding partition on a device formatted with | |
| * a MBR, Master Boot Record, or zero if the device is formatted as | |
| * a super floppy with the FAT boot sector in block zero. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. reasons for | |
| * failure include not finding a valid FAT16 file system in the | |
| * specified partition, a call to init() after a volume has | |
| * been successful initialized or an I/O error. | |
| * | |
| */ | |
| uint8_t Fat16::init(SdCard* dev, uint8_t part) { | |
| // error if invalid partition | |
| if (part > 4) return false; | |
| rawDev_ = dev; | |
| uint32_t volumeStartBlock = 0; | |
| // if part == 0 assume super floppy with FAT16 boot sector in block zero | |
| // if part > 0 assume mbr volume with partition table | |
| if (part) { | |
| if (!cacheRawBlock(volumeStartBlock)) return false; | |
| volumeStartBlock = cacheBuffer_.mbr.part[part - 1].firstSector; | |
| } | |
| if (!cacheRawBlock(volumeStartBlock)) return false; | |
| // check boot block signature | |
| if (cacheBuffer_.data[510] != BOOTSIG0 || | |
| cacheBuffer_.data[511] != BOOTSIG1) return false; | |
| bpb_t* bpb = &cacheBuffer_.fbs.bpb; | |
| fatCount_ = bpb->fatCount; | |
| blocksPerCluster_ = bpb->sectorsPerCluster; | |
| blocksPerFat_ = bpb->sectorsPerFat16; | |
| rootDirEntryCount_ = bpb->rootDirEntryCount; | |
| fatStartBlock_ = volumeStartBlock + bpb->reservedSectorCount; | |
| rootDirStartBlock_ = fatStartBlock_ + bpb->fatCount*bpb->sectorsPerFat16; | |
| dataStartBlock_ = rootDirStartBlock_ | |
| + ((32*bpb->rootDirEntryCount + 511)/512); | |
| uint32_t totalBlocks = bpb->totalSectors16 ? | |
| bpb->totalSectors16 : bpb->totalSectors32; | |
| clusterCount_ = (totalBlocks - (dataStartBlock_ - volumeStartBlock)) | |
| /bpb->sectorsPerCluster; | |
| // verify valid FAT16 volume | |
| if (bpb->bytesPerSector != 512 // only allow 512 byte blocks | |
| || bpb->sectorsPerFat16 == 0 // zero for FAT32 | |
| || clusterCount_ < 4085 // FAT12 if true | |
| || totalBlocks > 0X800000 // Max size for FAT16 volume | |
| || bpb->reservedSectorCount == 0 // invalid volume | |
| || bpb->fatCount == 0 // invalid volume | |
| || bpb->sectorsPerFat16 < (clusterCount_ >> 8) // invalid volume | |
| || bpb->sectorsPerCluster == 0 // invalid volume | |
| // power of 2 test | |
| || bpb->sectorsPerCluster & (bpb->sectorsPerCluster - 1)) { | |
| // not a usable FAT16 bpb | |
| return false; | |
| } | |
| volumeInitialized_ = 1; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** List directory contents to Serial. | |
| * | |
| * \param[in] flags The inclusive OR of | |
| * | |
| * LS_DATE - %Print file modification date | |
| * | |
| * LS_SIZE - %Print file size. | |
| */ | |
| void Fat16::ls(uint8_t flags) { | |
| dir_t d; | |
| for (uint16_t index = 0; readDir(&d, &index, DIR_ATT_VOLUME_ID); index++) { | |
| // print file name with possible blank fill | |
| printDirName(d, flags & (LS_DATE | LS_SIZE) ? 14 : 0); | |
| // print modify date/time if requested | |
| if (flags & LS_DATE) { | |
| printFatDate(d.lastWriteDate); | |
| Serial.write(' '); | |
| printFatTime(d.lastWriteTime); | |
| } | |
| // print size if requested | |
| if (DIR_IS_FILE(&d) && (flags & LS_SIZE)) { | |
| Serial.write(' '); | |
| Serial.print(d.fileSize); | |
| } | |
| Serial.println(); | |
| } | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Open a file by file name. | |
| * | |
| * \note The file must be in the root directory and must have a DOS | |
| * 8.3 name. | |
| * | |
| * \param[in] fileName A valid 8.3 DOS name for a file in the root directory. | |
| * | |
| * \param[in] oflag Values for \a oflag are constructed by a bitwise-inclusive | |
| * OR of flags from the following list | |
| * | |
| * O_READ - Open for reading. | |
| * | |
| * O_RDONLY - Same as O_READ. | |
| * | |
| * O_WRITE - Open for writing. | |
| * | |
| * O_WRONLY - Same as O_WRITE. | |
| * | |
| * O_RDWR - Open for reading and writing. | |
| * | |
| * O_APPEND - If set, the file offset shall be set to the end of the | |
| * file prior to each write. | |
| * | |
| * O_CREAT - If the file exists, this flag has no effect except as noted | |
| * under O_EXCL below. Otherwise, the file shall be created | |
| * | |
| * O_EXCL - If O_CREAT and O_EXCL are set, open() shall fail if the file exists. | |
| * | |
| * O_SYNC - Call sync() after each write. This flag should not be used with | |
| * write(uint8_t), write_P(PGM_P), writeln_P(PGM_P), or the Arduino Print class. | |
| * These functions do character a time writes so sync() will be called | |
| * after each byte. | |
| * | |
| * O_TRUNC - If the file exists and is a regular file, and the file is | |
| * successfully opened and is not read only, its length shall be truncated to 0. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include the FAT volume has not been initialized, | |
| * a file is already open, \a fileName is invalid, the file does not exist, | |
| * is a directory, or can't be opened in the access mode specified by oflag. | |
| */ | |
| uint8_t Fat16::open(const char* fileName, uint8_t oflag) { | |
| uint8_t dname[11]; // name formated for dir entry | |
| int16_t empty = -1; // index of empty slot | |
| dir_t* p; // pointer to cached dir entry | |
| if (!volumeInitialized_ || isOpen()) return false; | |
| // error if invalid name | |
| if (!make83Name(fileName, dname)) return false; | |
| for (uint16_t index = 0; index < rootDirEntryCount_; index++) { | |
| if (!(p = cacheDirEntry(index))) return false; | |
| if (p->name[0] == DIR_NAME_FREE || p->name[0] == DIR_NAME_DELETED) { | |
| // remember first empty slot | |
| if (empty < 0) empty = index; | |
| // done if no entries follow | |
| if (p->name[0] == DIR_NAME_FREE) break; | |
| } else if (!memcmp(dname, p->name, 11)) { | |
| // don't open existing file if O_CREAT and O_EXCL | |
| if ((oflag & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) return false; | |
| // open existing file | |
| return open(index, oflag); | |
| } | |
| } | |
| // error if directory is full | |
| if (empty < 0) return false; | |
| // only create file if O_CREAT and O_WRITE | |
| if ((oflag & (O_CREAT | O_WRITE)) != (O_CREAT | O_WRITE)) return false; | |
| if (!(p = cacheDirEntry(empty, CACHE_FOR_WRITE))) return false; | |
| // initialize as empty file | |
| memset(p, 0, sizeof(dir_t)); | |
| memcpy(p->name, dname, 11); | |
| // set timestamps | |
| if (dateTime_) { | |
| // call user function | |
| dateTime_(&p->creationDate, &p->creationTime); | |
| } else { | |
| // use default date/time | |
| p->creationDate = FAT_DEFAULT_DATE; | |
| p->creationTime = FAT_DEFAULT_TIME; | |
| } | |
| p->lastAccessDate = p->creationDate; | |
| p->lastWriteDate = p->creationDate; | |
| p->lastWriteTime = p->creationTime; | |
| // insure created directory entry will be written to storage device | |
| if (!cacheFlush()) return false; | |
| // open entry | |
| return open(empty, oflag); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Open a file by file index. | |
| * | |
| * \param[in] index The root directory index of the file to be opened. See \link | |
| * Fat16::readDir() readDir()\endlink. | |
| * | |
| * \param[in] oflag See \link Fat16::open(const char*, uint8_t)\endlink. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include the FAT volume has not been initialized, | |
| * a file is already open, \a index is invalid or is not the index of a | |
| * file or the file cannot be opened in the access mode specified by oflag. | |
| */ | |
| uint8_t Fat16::open(uint16_t index, uint8_t oflag) { | |
| if (!volumeInitialized_ || isOpen()) return false; | |
| if ((oflag & O_TRUNC) && !(oflag & O_WRITE)) return false; | |
| dir_t* d = cacheDirEntry(index); | |
| // if bad file index or I/O error | |
| if (!d) return false; | |
| // error if unused entry | |
| if (d->name[0] == DIR_NAME_FREE || d->name[0] == DIR_NAME_DELETED) { | |
| return false; | |
| } | |
| // error if long name, volume label or subdirectory | |
| if ((d->attributes & (DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY)) != 0) { | |
| return false; | |
| } | |
| // don't allow write or truncate if read-only | |
| if (d->attributes & DIR_ATT_READ_ONLY) { | |
| if (oflag & (O_WRITE | O_TRUNC)) return false; | |
| } | |
| curCluster_ = 0; | |
| curPosition_ = 0; | |
| dirEntryIndex_ = index; | |
| fileSize_ = d->fileSize; | |
| firstCluster_ = d->firstClusterLow; | |
| flags_ = oflag & (O_ACCMODE | O_SYNC | O_APPEND); | |
| if (oflag & O_TRUNC ) return truncate(0); | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** %Print the name field of a directory entry in 8.3 format to Serial. | |
| * | |
| * \param[in] dir The directory structure containing the name. | |
| * \param[in] width Blank fill name if length is less than \a width. | |
| */ | |
| void Fat16::printDirName(const dir_t& dir, uint8_t width) { | |
| uint8_t w = 0; | |
| for (uint8_t i = 0; i < 11; i++) { | |
| if (dir.name[i] == ' ') continue; | |
| if (i == 8) { | |
| Serial.write('.'); | |
| w++; | |
| } | |
| Serial.write(dir.name[i]); | |
| w++; | |
| } | |
| if (DIR_IS_SUBDIR(&dir)) { | |
| Serial.write('/'); | |
| w++; | |
| } | |
| while (w < width) { | |
| Serial.write(' '); | |
| w++; | |
| } | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** %Print a directory date field to Serial. | |
| * | |
| * Format is yyyy-mm-dd. | |
| * | |
| * \param[in] fatDate The date field from a directory entry. | |
| */ | |
| void Fat16::printFatDate(uint16_t fatDate) { | |
| Serial.print(FAT_YEAR(fatDate)); | |
| Serial.write('-'); | |
| printTwoDigits(FAT_MONTH(fatDate)); | |
| Serial.write('-'); | |
| printTwoDigits(FAT_DAY(fatDate)); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** %Print a directory time field to Serial. | |
| * | |
| * Format is hh:mm:ss. | |
| * | |
| * \param[in] fatTime The time field from a directory entry. | |
| */ | |
| void Fat16::printFatTime(uint16_t fatTime) { | |
| printTwoDigits(FAT_HOUR(fatTime)); | |
| Serial.write(':'); | |
| printTwoDigits(FAT_MINUTE(fatTime)); | |
| Serial.write(':'); | |
| printTwoDigits(FAT_SECOND(fatTime)); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** %Print a value as two digits to Serial. | |
| * | |
| * \param[in] v Value to be printed, 0 <= \a v <= 99 | |
| */ | |
| void Fat16::printTwoDigits(uint8_t v) { | |
| char str[3]; | |
| str[0] = '0' + v/10; | |
| str[1] = '0' + v % 10; | |
| str[2] = 0; | |
| Serial.print(str); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Read the next byte from a file. | |
| * | |
| * \return For success read returns the next byte in the file as an int. | |
| * If an error occurs or end of file is reached -1 is returned. | |
| */ | |
| int16_t Fat16::read(void) { | |
| uint8_t b; | |
| return read(&b, 1) == 1 ? b : -1; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Read data from a file at starting at the current file position. | |
| * | |
| * \param[out] buf Pointer to the location that will receive the data. | |
| * | |
| * \param[in] nbyte Maximum number of bytes to read. | |
| * | |
| * \return For success read returns the number of bytes read. | |
| * A value less than \a nbyte, including zero, may be returned | |
| * if end of file is reached. | |
| * If an error occurs, read returns -1. Possible errors include | |
| * read called before a file has been opened, the file has not been opened in | |
| * read mode, a corrupt file system, or an I/O error. | |
| */ | |
| int16_t Fat16::read(void* buf, uint16_t nbyte) { | |
| // convert void pointer to uin8_t pointer | |
| uint8_t* dst = reinterpret_cast<uint8_t*>(buf); | |
| // error if not open for read | |
| if (!(flags_ & O_READ)) return -1; | |
| // don't read beyond end of file | |
| if ((curPosition_ + nbyte) > fileSize_) nbyte = fileSize_ - curPosition_; | |
| // bytes left to read in loop | |
| uint16_t nToRead = nbyte; | |
| while (nToRead > 0) { | |
| uint8_t blkOfCluster = blockOfCluster(curPosition_); | |
| uint16_t blockOffset = cacheDataOffset(curPosition_); | |
| if (blkOfCluster == 0 && blockOffset == 0) { | |
| // start next cluster | |
| if (curCluster_ == 0) { | |
| curCluster_ = firstCluster_; | |
| } else { | |
| if (!fatGet(curCluster_, &curCluster_)) return -1; | |
| } | |
| // return error if bad cluster chain | |
| if (curCluster_ < 2 || isEOC(curCluster_)) return -1; | |
| } | |
| // cache data block | |
| if (!cacheRawBlock(dataBlockLba(curCluster_, blkOfCluster))) return -1; | |
| // location of data in cache | |
| uint8_t* src = cacheBuffer_.data + blockOffset; | |
| // max number of byte available in block | |
| uint16_t n = 512 - blockOffset; | |
| // lesser of available and amount to read | |
| if (n > nToRead) n = nToRead; | |
| // copy data to caller | |
| memcpy(dst, src, n); | |
| curPosition_ += n; | |
| dst += n; | |
| nToRead -= n; | |
| } | |
| return nbyte; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Read the next short, 8.3, directory entry. | |
| * | |
| * Unused entries and entries for long names are skipped. | |
| * | |
| * \param[out] dir Location that will receive the entry. | |
| * | |
| * \param[in,out] index The search starts at \a index and \a index is | |
| * updated with the root directory index of the found directory entry. | |
| * If the entry is a file, it may be opened by calling | |
| * \link Fat16::open(uint16_t, uint8_t) \endlink. | |
| * | |
| * \param[in] skip Skip entries that have these attributes. If \a skip | |
| * is not specified, the default is to skip the volume label and directories. | |
| * | |
| * \return The value one, true, is returned for success and the value zero, | |
| * false, is returned if an error occurs or the end of the root directory is | |
| * reached. On success, \a entry is set to the index of the found directory | |
| * entry. | |
| */ | |
| uint8_t Fat16::readDir(dir_t* dir, uint16_t* index, uint8_t skip) { | |
| dir_t* p; | |
| for (uint16_t i = *index; ; i++) { | |
| if (i >= rootDirEntryCount_) return false; | |
| if (!(p = cacheDirEntry(i))) return false; | |
| // done if beyond last used entry | |
| if (p->name[0] == DIR_NAME_FREE) return false; | |
| // skip deleted entry | |
| if (p->name[0] == DIR_NAME_DELETED) continue; | |
| // skip long names | |
| if ((p->attributes & DIR_ATT_LONG_NAME_MASK) == DIR_ATT_LONG_NAME) continue; | |
| // skip if attribute match | |
| if (p->attributes & skip) continue; | |
| // return found index | |
| *index = i; | |
| break; | |
| } | |
| memcpy(dir, p, sizeof(dir_t)); | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Remove a file. The directory entry and all data for the file are deleted. | |
| * | |
| * \note This function should not be used to delete the 8.3 version of a | |
| * file that has a long name. For example if a file has the long name | |
| * "New Text Document.txt" you should not delete the 8.3 name "NEWTEX~1.TXT". | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include the file is not open for write | |
| * or an I/O error occurred. | |
| */ | |
| uint8_t Fat16::remove(void) { | |
| // error if file is not open for write | |
| if (!(flags_ & O_WRITE)) return false; | |
| if (firstCluster_) { | |
| if (!freeChain(firstCluster_)) return false; | |
| } | |
| dir_t* d = cacheDirEntry(dirEntryIndex_, CACHE_FOR_WRITE); | |
| if (!d) return false; | |
| d->name[0] = DIR_NAME_DELETED; | |
| flags_ = 0; | |
| return cacheFlush(); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Remove a file. | |
| * | |
| * The directory entry and all data for the file are deleted. | |
| * | |
| * \param[in] fileName The name of the file to be removed. | |
| * | |
| * \note This function should not be used to delete the 8.3 version of a | |
| * file that has a long name. For example if a file has the long name | |
| * "New Text Document.txt" you should not delete the 8.3 name "NEWTEX~1.TXT". | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include the file is read only, \a fileName is not found | |
| * or an I/O error occurred. | |
| */ | |
| uint8_t Fat16::remove(const char* fileName) { | |
| Fat16 file; | |
| if (!file.open(fileName, O_WRITE)) return false; | |
| return file.remove(); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Sets the file's read/write position. | |
| * | |
| * \param[in] pos The new position in bytes from the beginning of the file. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| */ | |
| uint8_t Fat16::seekSet(uint32_t pos) { | |
| // error if file not open or seek past end of file | |
| if (!isOpen() || pos > fileSize_) return false; | |
| if (pos == 0) { | |
| // set position to start of file | |
| curCluster_ = 0; | |
| curPosition_ = 0; | |
| return true; | |
| } | |
| fat_t n = ((pos - 1) >> 9)/blocksPerCluster_; | |
| if (pos < curPosition_ || curPosition_ == 0) { | |
| // must follow chain from first cluster | |
| curCluster_ = firstCluster_; | |
| } else { | |
| // advance from curPosition | |
| n -= ((curPosition_ - 1) >> 9)/blocksPerCluster_; | |
| } | |
| while (n--) { | |
| if (!fatGet(curCluster_, &curCluster_)) return false; | |
| } | |
| curPosition_ = pos; | |
| return true; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * The sync() call causes all modified data and directory fields | |
| * to be written to the storage device. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include a call to sync() before a file has been | |
| * opened or an I/O error. | |
| */ | |
| uint8_t Fat16::sync(void) { | |
| if (flags_ & F_FILE_DIR_DIRTY) { | |
| // cache directory entry | |
| dir_t* d = cacheDirEntry(dirEntryIndex_, CACHE_FOR_WRITE); | |
| if (!d) return false; | |
| // update file size and first cluster | |
| d->fileSize = fileSize_; | |
| d->firstClusterLow = firstCluster_; | |
| // set modify time if user supplied a callback date/time function | |
| if (dateTime_) { | |
| dateTime_(&d->lastWriteDate, &d->lastWriteTime); | |
| d->lastAccessDate = d->lastWriteDate; | |
| } | |
| flags_ &= ~F_FILE_DIR_DIRTY; | |
| } | |
| return cacheFlush(); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * The timestamp() call sets a file's timestamps in its directory entry. | |
| * | |
| * \param[in] flags Values for \a flags are constructed by a bitwise-inclusive | |
| * OR of flags from the following list | |
| * | |
| * T_ACCESS - Set the file's last access date. | |
| * | |
| * T_CREATE - Set the file's creation date and time. | |
| * | |
| * T_WRITE - Set the file's last write/modification date and time. | |
| * | |
| * \param[in] year Valid range 1980 - 2107 inclusive. | |
| * | |
| * \param[in] month Valid range 1 - 12 inclusive. | |
| * | |
| * \param[in] day Valid range 1 - 31 inclusive. | |
| * | |
| * \param[in] hour Valid range 0 - 23 inclusive. | |
| * | |
| * \param[in] minute Valid range 0 - 59 inclusive. | |
| * | |
| * \param[in] second Valid range 0 - 59 inclusive | |
| * | |
| * \note It is possible to set an invalid date since there is no check for | |
| * the number of days in a month. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| */ | |
| uint8_t Fat16::timestamp(uint8_t flags, uint16_t year, uint8_t month, | |
| uint8_t day, uint8_t hour, uint8_t minute, uint8_t second) { | |
| if (!isOpen() | |
| || year < 1980 | |
| || year > 2107 | |
| || month < 1 | |
| || month > 12 | |
| || day < 1 | |
| || day > 31 | |
| || hour > 23 | |
| || minute > 59 | |
| || second > 59) { | |
| return false; | |
| } | |
| dir_t* d = cacheDirEntry(dirEntryIndex_, CACHE_FOR_WRITE); | |
| if (!d) return false; | |
| uint16_t dirDate = FAT_DATE(year, month, day); | |
| uint16_t dirTime = FAT_TIME(hour, minute, second); | |
| if (flags & T_ACCESS) { | |
| d->lastAccessDate = dirDate; | |
| } | |
| if (flags & T_CREATE) { | |
| d->creationDate = dirDate; | |
| d->creationTime = dirTime; | |
| // seems to be units of 1/100 second not 1/10 as Microsoft standard states | |
| d->creationTimeTenths = second & 1 ? 100 : 0; | |
| } | |
| if (flags & T_WRITE) { | |
| d->lastWriteDate = dirDate; | |
| d->lastWriteTime = dirTime; | |
| } | |
| cacheSetDirty(); | |
| return sync(); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Truncate a file to a specified length. The current file position | |
| * will be maintained if it is less than or equal to \a length otherwise | |
| * it will be set to end of file. | |
| * | |
| * \param[in] length The desired length for the file. | |
| * | |
| * \return The value one, true, is returned for success and | |
| * the value zero, false, is returned for failure. | |
| * Reasons for failure include file is read only, file is a directory, | |
| * \a length is greater than the current file size or an I/O error occurs. | |
| */ | |
| uint8_t Fat16::truncate(uint32_t length) { | |
| // error if file is not open for write | |
| if (!(flags_ & O_WRITE)) return false; | |
| if (length > fileSize_) return false; | |
| // fileSize and length are zero - nothing to do | |
| if (fileSize_ == 0) return true; | |
| uint32_t newPos = curPosition_ > length ? length : curPosition_; | |
| if (length == 0) { | |
| // free all clusters | |
| if (!freeChain(firstCluster_)) return false; | |
| curCluster_ = firstCluster_ = 0; | |
| } else { | |
| fat_t toFree; | |
| if (!seekSet(length)) return false; | |
| if (!fatGet(curCluster_, &toFree)) return false; | |
| if (!isEOC(toFree)) { | |
| // free extra clusters | |
| if (!fatPut(curCluster_, FAT16EOC)) return false; | |
| if (!freeChain(toFree)) return false; | |
| } | |
| } | |
| fileSize_ = length; | |
| flags_ |= F_FILE_DIR_DIRTY; | |
| if (!sync()) return false; | |
| return seekSet(newPos); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Write data at the current position of an open file. | |
| * | |
| * \note Data is moved to the cache but may not be written to the | |
| * storage device until sync() is called. | |
| * | |
| * \param[in] buf Pointer to the location of the data to be written. | |
| * | |
| * \param[in] nbyte Number of bytes to write. | |
| * | |
| * \return For success write() returns the number of bytes written, always | |
| * \a nbyte. If an error occurs, write() returns -1. Possible errors include | |
| * write() is called before a file has been opened, the file has not been opened | |
| * for write, device is full, a corrupt file system or an I/O error. | |
| * | |
| */ | |
| int16_t Fat16::write(const void* buf, uint16_t nbyte) { | |
| uint16_t nToWrite = nbyte; | |
| const uint8_t* src = reinterpret_cast<const uint8_t*>(buf); | |
| // error if file is not open for write | |
| if (!(flags_ & O_WRITE)) goto writeErrorReturn; | |
| // go to end of file if O_APPEND | |
| if ((flags_ & O_APPEND) && curPosition_ != fileSize_) { | |
| if (!seekEnd()) goto writeErrorReturn; | |
| } | |
| while (nToWrite > 0) { | |
| uint8_t blkOfCluster = blockOfCluster(curPosition_); | |
| uint16_t blockOffset = cacheDataOffset(curPosition_); | |
| if (blkOfCluster == 0 && blockOffset == 0) { | |
| // start of new cluster | |
| if (curCluster_ == 0) { | |
| if (firstCluster_ == 0) { | |
| // allocate first cluster of file | |
| if (!addCluster()) goto writeErrorReturn; | |
| } else { | |
| curCluster_ = firstCluster_; | |
| } | |
| } else { | |
| fat_t next; | |
| if (!fatGet(curCluster_, &next)) goto writeErrorReturn; | |
| if (isEOC(next)) { | |
| // add cluster if at end of chain | |
| if (!addCluster()) goto writeErrorReturn; | |
| } else { | |
| curCluster_ = next; | |
| } | |
| } | |
| } | |
| uint32_t lba = dataBlockLba(curCluster_, blkOfCluster); | |
| if (blockOffset == 0 && curPosition_ >= fileSize_) { | |
| // start of new block don't need to read into cache | |
| if (!cacheFlush()) goto writeErrorReturn; | |
| cacheBlockNumber_ = lba; | |
| cacheSetDirty(); | |
| } else { | |
| // rewrite part of block | |
| if (!cacheRawBlock(lba, CACHE_FOR_WRITE)) return -1; | |
| } | |
| uint8_t* dst = cacheBuffer_.data + blockOffset; | |
| // max space in block | |
| uint16_t n = 512 - blockOffset; | |
| // lesser of space and amount to write | |
| if (n > nToWrite) n = nToWrite; | |
| // copy data to cache | |
| memcpy(dst, src, n); | |
| curPosition_ += n; | |
| nToWrite -= n; | |
| src += n; | |
| } | |
| if (curPosition_ > fileSize_) { | |
| // update fileSize and insure sync will update dir entry | |
| fileSize_ = curPosition_; | |
| flags_ |= F_FILE_DIR_DIRTY; | |
| } else if (dateTime_ && nbyte) { | |
| // insure sync will update modified date and time | |
| flags_ |= F_FILE_DIR_DIRTY; | |
| } | |
| if (flags_ & O_SYNC) { | |
| if (!sync()) goto writeErrorReturn; | |
| } | |
| return nbyte; | |
| writeErrorReturn: | |
| writeError = true; | |
| return -1; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Write a byte to a file. Required by the Arduino Print class. | |
| * | |
| * Use Fat16::writeError to check for errors. | |
| */ | |
| void Fat16::write(uint8_t b) { | |
| write(&b, 1); | |
| } | |
| size_t Fat16::write(uint8_t b) { | |
| return write(&b, 1) == 1 ? 1 : 0; | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Write a string to a file. Used by the Arduino Print class. | |
| * | |
| * Use Fat16::writeError to check for errors. | |
| */ | |
| void Fat16::write(const char* str) { | |
| write(str, strlen(str)); | |
| } | |
| int16_t Fat16::write(const char* str) { | |
| return write(str, strlen(str)); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Write a PROGMEM string to a file. | |
| * | |
| * Use Fat16::writeError to check for errors. | |
| */ | |
| void Fat16::write_P(PGM_P str) { | |
| for (uint8_t c; (c = pgm_read_byte(str)); str++) write(c); | |
| } | |
| //------------------------------------------------------------------------------ | |
| /** | |
| * Write a PROGMEM string followed by CR/LF to a file. | |
| * | |
| * Use Fat16::writeError to check for errors. | |
| */ | |
| void Fat16::writeln_P(PGM_P str) { | |
| write_P(str); | |
| println(); | |
| } | |