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Diffstat (limited to 'libraries/Robot_Control/Fat16.cpp')
| -rw-r--r-- | libraries/Robot_Control/Fat16.cpp | 990 |
1 files changed, 990 insertions, 0 deletions
diff --git a/libraries/Robot_Control/Fat16.cpp b/libraries/Robot_Control/Fat16.cpp new file mode 100644 index 0000000..aa8f585 --- /dev/null +++ b/libraries/Robot_Control/Fat16.cpp @@ -0,0 +1,990 @@ +/* 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/>. + */ +#include <avr/pgmspace.h> +#if ARDUINO < 100 +#include <WProgram.h> +#else // ARDUINO +#include <Arduino.h> +#endif // ARDUINO +#include <Fat16.h> +//----------------------------------------------------------------------------- +// 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; + +#if ALLOW_DEPRECATED_FUNCTIONS +void (*Fat16::oldDateTime_)(uint16_t& date, uint16_t& time) = NULL; // NOLINT +#endif // ALLOW_DEPRECATED_FUNCTIONS +//------------------------------------------------------------------------------ +// 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. + */ +#if ARDUINO < 100 +void Fat16::write(uint8_t b) { + write(&b, 1); +} +#else // ARDUINO < 100 +size_t Fat16::write(uint8_t b) { + return write(&b, 1) == 1 ? 1 : 0; +} +#endif // ARDUINO < 100 +//------------------------------------------------------------------------------ +/** + * Write a string to a file. Used by the Arduino Print class. + * + * Use Fat16::writeError to check for errors. + */ +#if ARDUINO < 100 +void Fat16::write(const char* str) { + write(str, strlen(str)); +} +#else // ARDUINO < 100 +int16_t Fat16::write(const char* str) { + return write(str, strlen(str)); +} +#endif // ARDUINO < 100 +//------------------------------------------------------------------------------ +/** + * 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(); +} |