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  1. /* FatLib Library
  2. * Copyright (C) 2013 by William Greiman
  3. *
  4. * This file is part of the FatLib Library
  5. *
  6. * This Library is free software: you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License as published by
  8. * the Free Software Foundation, either version 3 of the License, or
  9. * (at your option) any later version.
  10. *
  11. * This Library is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. * GNU General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU General Public License
  17. * along with the FatLib Library. If not, see
  18. * <http://www.gnu.org/licenses/>.
  19. */
  20. #ifndef FatStructs_h
  21. #define FatStructs_h
  22. /**
  23. * \file
  24. * \brief FAT file structures
  25. */
  26. /*
  27. * mostly from Microsoft document fatgen103.doc
  28. * http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx
  29. */
  30. //------------------------------------------------------------------------------
  31. /** Value for byte 510 of boot block or MBR */
  32. uint8_t const BOOTSIG0 = 0X55;
  33. /** Value for byte 511 of boot block or MBR */
  34. uint8_t const BOOTSIG1 = 0XAA;
  35. /** Value for bootSignature field int FAT/FAT32 boot sector */
  36. uint8_t const EXTENDED_BOOT_SIG = 0X29;
  37. //------------------------------------------------------------------------------
  38. /**
  39. * \struct partitionTable
  40. * \brief MBR partition table entry
  41. *
  42. * A partition table entry for a MBR formatted storage device.
  43. * The MBR partition table has four entries.
  44. */
  45. struct partitionTable {
  46. /**
  47. * Boot Indicator . Indicates whether the volume is the active
  48. * partition. Legal values include: 0X00. Do not use for booting.
  49. * 0X80 Active partition.
  50. */
  51. uint8_t boot;
  52. /**
  53. * Head part of Cylinder-head-sector address of the first block in
  54. * the partition. Legal values are 0-255. Only used in old PC BIOS.
  55. */
  56. uint8_t beginHead;
  57. /**
  58. * Sector part of Cylinder-head-sector address of the first block in
  59. * the partition. Legal values are 1-63. Only used in old PC BIOS.
  60. */
  61. unsigned beginSector : 6;
  62. /** High bits cylinder for first block in partition. */
  63. unsigned beginCylinderHigh : 2;
  64. /**
  65. * Combine beginCylinderLow with beginCylinderHigh. Legal values
  66. * are 0-1023. Only used in old PC BIOS.
  67. */
  68. uint8_t beginCylinderLow;
  69. /**
  70. * Partition type. See defines that begin with PART_TYPE_ for
  71. * some Microsoft partition types.
  72. */
  73. uint8_t type;
  74. /**
  75. * head part of cylinder-head-sector address of the last sector in the
  76. * partition. Legal values are 0-255. Only used in old PC BIOS.
  77. */
  78. uint8_t endHead;
  79. /**
  80. * Sector part of cylinder-head-sector address of the last sector in
  81. * the partition. Legal values are 1-63. Only used in old PC BIOS.
  82. */
  83. unsigned endSector : 6;
  84. /** High bits of end cylinder */
  85. unsigned endCylinderHigh : 2;
  86. /**
  87. * Combine endCylinderLow with endCylinderHigh. Legal values
  88. * are 0-1023. Only used in old PC BIOS.
  89. */
  90. uint8_t endCylinderLow;
  91. /** Logical block address of the first block in the partition. */
  92. uint32_t firstSector;
  93. /** Length of the partition, in blocks. */
  94. uint32_t totalSectors;
  95. }__attribute__((packed));
  96. /** Type name for partitionTable */
  97. typedef struct partitionTable part_t;
  98. //------------------------------------------------------------------------------
  99. /**
  100. * \struct masterBootRecord
  101. *
  102. * \brief Master Boot Record
  103. *
  104. * The first block of a storage device that is formatted with a MBR.
  105. */
  106. struct masterBootRecord {
  107. /** Code Area for master boot program. */
  108. uint8_t codeArea[440];
  109. /** Optional Windows NT disk signature. May contain boot code. */
  110. uint32_t diskSignature;
  111. /** Usually zero but may be more boot code. */
  112. uint16_t usuallyZero;
  113. /** Partition tables. */
  114. part_t part[4];
  115. /** First MBR signature byte. Must be 0X55 */
  116. uint8_t mbrSig0;
  117. /** Second MBR signature byte. Must be 0XAA */
  118. uint8_t mbrSig1;
  119. }__attribute__((packed));
  120. /** Type name for masterBootRecord */
  121. typedef struct masterBootRecord mbr_t;
  122. //------------------------------------------------------------------------------
  123. /**
  124. * \struct fat_boot
  125. *
  126. * \brief Boot sector for a FAT12/FAT16 volume.
  127. *
  128. */
  129. struct fat_boot {
  130. /**
  131. * The first three bytes of the boot sector must be valid,
  132. * executable x 86-based CPU instructions. This includes a
  133. * jump instruction that skips the next non-executable bytes.
  134. */
  135. uint8_t jump[3];
  136. /**
  137. * This is typically a string of characters that identifies
  138. * the operating system that formatted the volume.
  139. */
  140. char oemId[8];
  141. /**
  142. * The size of a hardware sector. Valid decimal values for this
  143. * field are 512, 1024, 2048, and 4096. For most disks used in
  144. * the United States, the value of this field is 512.
  145. */
  146. uint16_t bytesPerSector;
  147. /**
  148. * Number of sectors per allocation unit. This value must be a
  149. * power of 2 that is greater than 0. The legal values are
  150. * 1, 2, 4, 8, 16, 32, 64, and 128. 128 should be avoided.
  151. */
  152. uint8_t sectorsPerCluster;
  153. /**
  154. * The number of sectors preceding the start of the first FAT,
  155. * including the boot sector. The value of this field is always 1.
  156. */
  157. uint16_t reservedSectorCount;
  158. /**
  159. * The number of copies of the FAT on the volume.
  160. * The value of this field is always 2.
  161. */
  162. uint8_t fatCount;
  163. /**
  164. * For FAT12 and FAT16 volumes, this field contains the count of
  165. * 32-byte directory entries in the root directory. For FAT32 volumes,
  166. * this field must be set to 0. For FAT12 and FAT16 volumes, this
  167. * value should always specify a count that when multiplied by 32
  168. * results in a multiple of bytesPerSector. FAT16 volumes should
  169. * use the value 512.
  170. */
  171. uint16_t rootDirEntryCount;
  172. /**
  173. * This field is the old 16-bit total count of sectors on the volume.
  174. * This count includes the count of all sectors in all four regions
  175. * of the volume. This field can be 0; if it is 0, then totalSectors32
  176. * must be non-zero. For FAT32 volumes, this field must be 0. For
  177. * FAT12 and FAT16 volumes, this field contains the sector count, and
  178. * totalSectors32 is 0 if the total sector count fits
  179. * (is less than 0x10000).
  180. */
  181. uint16_t totalSectors16;
  182. /**
  183. * This dates back to the old MS-DOS 1.x media determination and is
  184. * no longer usually used for anything. 0xF8 is the standard value
  185. * for fixed (nonremovable) media. For removable media, 0xF0 is
  186. * frequently used. Legal values are 0xF0 or 0xF8-0xFF.
  187. */
  188. uint8_t mediaType;
  189. /**
  190. * Count of sectors occupied by one FAT on FAT12/FAT16 volumes.
  191. * On FAT32 volumes this field must be 0, and sectorsPerFat32
  192. * contains the FAT size count.
  193. */
  194. uint16_t sectorsPerFat16;
  195. /** Sectors per track for interrupt 0x13. Not used otherwise. */
  196. uint16_t sectorsPerTrack;
  197. /** Number of heads for interrupt 0x13. Not used otherwise. */
  198. uint16_t headCount;
  199. /**
  200. * Count of hidden sectors preceding the partition that contains this
  201. * FAT volume. This field is generally only relevant for media
  202. * visible on interrupt 0x13.
  203. */
  204. uint32_t hidddenSectors;
  205. /**
  206. * This field is the new 32-bit total count of sectors on the volume.
  207. * This count includes the count of all sectors in all four regions
  208. * of the volume. This field can be 0; if it is 0, then
  209. * totalSectors16 must be non-zero.
  210. */
  211. uint32_t totalSectors32;
  212. /**
  213. * Related to the BIOS physical drive number. Floppy drives are
  214. * identified as 0x00 and physical hard disks are identified as
  215. * 0x80, regardless of the number of physical disk drives.
  216. * Typically, this value is set prior to issuing an INT 13h BIOS
  217. * call to specify the device to access. The value is only
  218. * relevant if the device is a boot device.
  219. */
  220. uint8_t driveNumber;
  221. /** used by Windows NT - should be zero for FAT */
  222. uint8_t reserved1;
  223. /** 0X29 if next three fields are valid */
  224. uint8_t bootSignature;
  225. /**
  226. * A random serial number created when formatting a disk,
  227. * which helps to distinguish between disks.
  228. * Usually generated by combining date and time.
  229. */
  230. uint32_t volumeSerialNumber;
  231. /**
  232. * A field once used to store the volume label. The volume label
  233. * is now stored as a special file in the root directory.
  234. */
  235. char volumeLabel[11];
  236. /**
  237. * A field with a value of either FAT, FAT12 or FAT16,
  238. * depending on the disk format.
  239. */
  240. char fileSystemType[8];
  241. /** X86 boot code */
  242. uint8_t bootCode[448];
  243. /** must be 0X55 */
  244. uint8_t bootSectorSig0;
  245. /** must be 0XAA */
  246. uint8_t bootSectorSig1;
  247. }__attribute__((packed));
  248. /** Type name for FAT Boot Sector */
  249. typedef struct fat_boot fat_boot_t;
  250. //------------------------------------------------------------------------------
  251. /**
  252. * \struct fat32_boot
  253. *
  254. * \brief Boot sector for a FAT32 volume.
  255. *
  256. */
  257. struct fat32_boot {
  258. /**
  259. * The first three bytes of the boot sector must be valid,
  260. * executable x 86-based CPU instructions. This includes a
  261. * jump instruction that skips the next non-executable bytes.
  262. */
  263. uint8_t jump[3];
  264. /**
  265. * This is typically a string of characters that identifies
  266. * the operating system that formatted the volume.
  267. */
  268. char oemId[8];
  269. /**
  270. * The size of a hardware sector. Valid decimal values for this
  271. * field are 512, 1024, 2048, and 4096. For most disks used in
  272. * the United States, the value of this field is 512.
  273. */
  274. uint16_t bytesPerSector;
  275. /**
  276. * Number of sectors per allocation unit. This value must be a
  277. * power of 2 that is greater than 0. The legal values are
  278. * 1, 2, 4, 8, 16, 32, 64, and 128. 128 should be avoided.
  279. */
  280. uint8_t sectorsPerCluster;
  281. /**
  282. * The number of sectors preceding the start of the first FAT,
  283. * including the boot sector. Must not be zero
  284. */
  285. uint16_t reservedSectorCount;
  286. /**
  287. * The number of copies of the FAT on the volume.
  288. * The value of this field is always 2.
  289. */
  290. uint8_t fatCount;
  291. /**
  292. * FAT12/FAT16 only. For FAT32 volumes, this field must be set to 0.
  293. */
  294. uint16_t rootDirEntryCount;
  295. /**
  296. * For FAT32 volumes, this field must be 0.
  297. */
  298. uint16_t totalSectors16;
  299. /**
  300. * This dates back to the old MS-DOS 1.x media determination and is
  301. * no longer usually used for anything. 0xF8 is the standard value
  302. * for fixed (non-removable) media. For removable media, 0xF0 is
  303. * frequently used. Legal values are 0xF0 or 0xF8-0xFF.
  304. */
  305. uint8_t mediaType;
  306. /**
  307. * On FAT32 volumes this field must be 0, and sectorsPerFat32
  308. * contains the FAT size count.
  309. */
  310. uint16_t sectorsPerFat16;
  311. /** Sectors per track for interrupt 0x13. Not used otherwise. */
  312. uint16_t sectorsPerTrack;
  313. /** Number of heads for interrupt 0x13. Not used otherwise. */
  314. uint16_t headCount;
  315. /**
  316. * Count of hidden sectors preceding the partition that contains this
  317. * FAT volume. This field is generally only relevant for media
  318. * visible on interrupt 0x13.
  319. */
  320. uint32_t hidddenSectors;
  321. /**
  322. * Contains the total number of sectors in the FAT32 volume.
  323. */
  324. uint32_t totalSectors32;
  325. /**
  326. * Count of sectors occupied by one FAT on FAT32 volumes.
  327. */
  328. uint32_t sectorsPerFat32;
  329. /**
  330. * This field is only defined for FAT32 media and does not exist on
  331. * FAT12 and FAT16 media.
  332. * Bits 0-3 -- Zero-based number of active FAT.
  333. * Only valid if mirroring is disabled.
  334. * Bits 4-6 -- Reserved.
  335. * Bit 7 -- 0 means the FAT is mirrored at runtime into all FATs.
  336. * -- 1 means only one FAT is active; it is the one referenced
  337. * in bits 0-3.
  338. * Bits 8-15 -- Reserved.
  339. */
  340. uint16_t fat32Flags;
  341. /**
  342. * FAT32 version. High byte is major revision number.
  343. * Low byte is minor revision number. Only 0.0 define.
  344. */
  345. uint16_t fat32Version;
  346. /**
  347. * Cluster number of the first cluster of the root directory for FAT32.
  348. * This usually 2 but not required to be 2.
  349. */
  350. uint32_t fat32RootCluster;
  351. /**
  352. * Sector number of FSINFO structure in the reserved area of the
  353. * FAT32 volume. Usually 1.
  354. */
  355. uint16_t fat32FSInfo;
  356. /**
  357. * If non-zero, indicates the sector number in the reserved area
  358. * of the volume of a copy of the boot record. Usually 6.
  359. * No value other than 6 is recommended.
  360. */
  361. uint16_t fat32BackBootBlock;
  362. /**
  363. * Reserved for future expansion. Code that formats FAT32 volumes
  364. * should always set all of the bytes of this field to 0.
  365. */
  366. uint8_t fat32Reserved[12];
  367. /**
  368. * Related to the BIOS physical drive number. Floppy drives are
  369. * identified as 0x00 and physical hard disks are identified as
  370. * 0x80, regardless of the number of physical disk drives.
  371. * Typically, this value is set prior to issuing an INT 13h BIOS
  372. * call to specify the device to access. The value is only
  373. * relevant if the device is a boot device.
  374. */
  375. uint8_t driveNumber;
  376. /** used by Windows NT - should be zero for FAT */
  377. uint8_t reserved1;
  378. /** 0X29 if next three fields are valid */
  379. uint8_t bootSignature;
  380. /**
  381. * A random serial number created when formatting a disk,
  382. * which helps to distinguish between disks.
  383. * Usually generated by combining date and time.
  384. */
  385. uint32_t volumeSerialNumber;
  386. /**
  387. * A field once used to store the volume label. The volume label
  388. * is now stored as a special file in the root directory.
  389. */
  390. char volumeLabel[11];
  391. /**
  392. * A text field with a value of FAT32.
  393. */
  394. char fileSystemType[8];
  395. /** X86 boot code */
  396. uint8_t bootCode[420];
  397. /** must be 0X55 */
  398. uint8_t bootSectorSig0;
  399. /** must be 0XAA */
  400. uint8_t bootSectorSig1;
  401. }__attribute__((packed));
  402. /** Type name for FAT32 Boot Sector */
  403. typedef struct fat32_boot fat32_boot_t;
  404. //------------------------------------------------------------------------------
  405. /** Lead signature for a FSINFO sector */
  406. uint32_t const FSINFO_LEAD_SIG = 0x41615252;
  407. /** Struct signature for a FSINFO sector */
  408. uint32_t const FSINFO_STRUCT_SIG = 0x61417272;
  409. /**
  410. * \struct fat32_fsinfo
  411. *
  412. * \brief FSINFO sector for a FAT32 volume.
  413. *
  414. */
  415. struct fat32_fsinfo {
  416. /** must be 0X52, 0X52, 0X61, 0X41 */
  417. uint32_t leadSignature;
  418. /** must be zero */
  419. uint8_t reserved1[480];
  420. /** must be 0X72, 0X72, 0X41, 0X61 */
  421. uint32_t structSignature;
  422. /**
  423. * Contains the last known free cluster count on the volume.
  424. * If the value is 0xFFFFFFFF, then the free count is unknown
  425. * and must be computed. Any other value can be used, but is
  426. * not necessarily correct. It should be range checked at least
  427. * to make sure it is <= volume cluster count.
  428. */
  429. uint32_t freeCount;
  430. /**
  431. * This is a hint for the FAT driver. It indicates the cluster
  432. * number at which the driver should start looking for free clusters.
  433. * If the value is 0xFFFFFFFF, then there is no hint and the driver
  434. * should start looking at cluster 2.
  435. */
  436. uint32_t nextFree;
  437. /** must be zero */
  438. uint8_t reserved2[12];
  439. /** must be 0X00, 0X00, 0X55, 0XAA */
  440. uint8_t tailSignature[4];
  441. }__attribute__((packed));
  442. /** Type name for FAT32 FSINFO Sector */
  443. typedef struct fat32_fsinfo fat32_fsinfo_t;
  444. //------------------------------------------------------------------------------
  445. // End Of Chain values for FAT entries
  446. /** FAT12 end of chain value used by Microsoft. */
  447. uint16_t const FAT12EOC = 0XFFF;
  448. /** Minimum value for FAT12 EOC. Use to test for EOC. */
  449. uint16_t const FAT12EOC_MIN = 0XFF8;
  450. /** FAT16 end of chain value used by Microsoft. */
  451. uint16_t const FAT16EOC = 0XFFFF;
  452. /** Minimum value for FAT16 EOC. Use to test for EOC. */
  453. uint16_t const FAT16EOC_MIN = 0XFFF8;
  454. /** FAT32 end of chain value used by Microsoft. */
  455. uint32_t const FAT32EOC = 0X0FFFFFFF;
  456. /** Minimum value for FAT32 EOC. Use to test for EOC. */
  457. uint32_t const FAT32EOC_MIN = 0X0FFFFFF8;
  458. /** Mask a for FAT32 entry. Entries are 28 bits. */
  459. uint32_t const FAT32MASK = 0X0FFFFFFF;
  460. //------------------------------------------------------------------------------
  461. /**
  462. * \struct directoryEntry
  463. * \brief FAT short directory entry
  464. *
  465. * Short means short 8.3 name, not the entry size.
  466. *
  467. * Date Format. A FAT directory entry date stamp is a 16-bit field that is
  468. * basically a date relative to the MS-DOS epoch of 01/01/1980. Here is the
  469. * format (bit 0 is the LSB of the 16-bit word, bit 15 is the MSB of the
  470. * 16-bit word):
  471. *
  472. * Bits 9-15: Count of years from 1980, valid value range 0-127
  473. * inclusive (1980-2107).
  474. *
  475. * Bits 5-8: Month of year, 1 = January, valid value range 1-12 inclusive.
  476. *
  477. * Bits 0-4: Day of month, valid value range 1-31 inclusive.
  478. *
  479. * Time Format. A FAT directory entry time stamp is a 16-bit field that has
  480. * a granularity of 2 seconds. Here is the format (bit 0 is the LSB of the
  481. * 16-bit word, bit 15 is the MSB of the 16-bit word).
  482. *
  483. * Bits 11-15: Hours, valid value range 0-23 inclusive.
  484. *
  485. * Bits 5-10: Minutes, valid value range 0-59 inclusive.
  486. *
  487. * Bits 0-4: 2-second count, valid value range 0-29 inclusive (0 - 58 seconds).
  488. *
  489. * The valid time range is from Midnight 00:00:00 to 23:59:58.
  490. */
  491. struct directoryEntry {
  492. /** Short 8.3 name.
  493. *
  494. * The first eight bytes contain the file name with blank fill.
  495. * The last three bytes contain the file extension with blank fill.
  496. */
  497. uint8_t name[11];
  498. /** Entry attributes.
  499. *
  500. * The upper two bits of the attribute byte are reserved and should
  501. * always be set to 0 when a file is created and never modified or
  502. * looked at after that. See defines that begin with DIR_ATT_.
  503. */
  504. uint8_t attributes;
  505. /**
  506. * Reserved for use by Windows NT. Set value to 0 when a file is
  507. * created and never modify or look at it after that.
  508. */
  509. uint8_t reservedNT;
  510. /**
  511. * The granularity of the seconds part of creationTime is 2 seconds
  512. * so this field is a count of tenths of a second and its valid
  513. * value range is 0-199 inclusive. (WHG note - seems to be hundredths)
  514. */
  515. uint8_t creationTimeTenths;
  516. /** Time file was created. */
  517. uint16_t creationTime;
  518. /** Date file was created. */
  519. uint16_t creationDate;
  520. /**
  521. * Last access date. Note that there is no last access time, only
  522. * a date. This is the date of last read or write. In the case of
  523. * a write, this should be set to the same date as lastWriteDate.
  524. */
  525. uint16_t lastAccessDate;
  526. /**
  527. * High word of this entry's first cluster number (always 0 for a
  528. * FAT12 or FAT16 volume).
  529. */
  530. uint16_t firstClusterHigh;
  531. /** Time of last write. File creation is considered a write. */
  532. uint16_t lastWriteTime;
  533. /** Date of last write. File creation is considered a write. */
  534. uint16_t lastWriteDate;
  535. /** Low word of this entry's first cluster number. */
  536. uint16_t firstClusterLow;
  537. /** 32-bit unsigned holding this file's size in bytes. */
  538. uint32_t fileSize;
  539. }__attribute__((packed));
  540. //------------------------------------------------------------------------------
  541. // Definitions for directory entries
  542. //
  543. /** Type name for directoryEntry */
  544. typedef struct directoryEntry dir_t;
  545. /** escape for name[0] = 0XE5 */
  546. uint8_t const DIR_NAME_0XE5 = 0X05;
  547. /** name[0] value for entry that is free after being "deleted" */
  548. uint8_t const DIR_NAME_DELETED = 0XE5;
  549. /** name[0] value for entry that is free and no allocated entries follow */
  550. uint8_t const DIR_NAME_FREE = 0X00;
  551. /** file is read-only */
  552. uint8_t const DIR_ATT_READ_ONLY = 0X01;
  553. /** File should hidden in directory listings */
  554. uint8_t const DIR_ATT_HIDDEN = 0X02;
  555. /** Entry is for a system file */
  556. uint8_t const DIR_ATT_SYSTEM = 0X04;
  557. /** Directory entry contains the volume label */
  558. uint8_t const DIR_ATT_VOLUME_ID = 0X08;
  559. /** Entry is for a directory */
  560. uint8_t const DIR_ATT_DIRECTORY = 0X10;
  561. /** Old DOS archive bit for backup support */
  562. uint8_t const DIR_ATT_ARCHIVE = 0X20;
  563. /** Test value for long name entry. Test is
  564. (d->attributes & DIR_ATT_LONG_NAME_MASK) == DIR_ATT_LONG_NAME. */
  565. uint8_t const DIR_ATT_LONG_NAME = 0X0F;
  566. /** Test mask for long name entry */
  567. uint8_t const DIR_ATT_LONG_NAME_MASK = 0X3F;
  568. /** defined attribute bits */
  569. uint8_t const DIR_ATT_DEFINED_BITS = 0X3F;
  570. /** Directory entry is part of a long name
  571. * \param[in] dir Pointer to a directory entry.
  572. *
  573. * \return true if the entry is for part of a long name else false.
  574. */
  575. static inline uint8_t DIR_IS_LONG_NAME(const dir_t* dir) {
  576. return (dir->attributes & DIR_ATT_LONG_NAME_MASK) == DIR_ATT_LONG_NAME;
  577. }
  578. /** Mask for file/subdirectory tests */
  579. uint8_t const DIR_ATT_FILE_TYPE_MASK = (DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY);
  580. /** Directory entry is for a file
  581. * \param[in] dir Pointer to a directory entry.
  582. *
  583. * \return true if the entry is for a normal file else false.
  584. */
  585. static inline uint8_t DIR_IS_FILE(const dir_t* dir) {
  586. return (dir->attributes & DIR_ATT_FILE_TYPE_MASK) == 0;
  587. }
  588. /** Directory entry is for a subdirectory
  589. * \param[in] dir Pointer to a directory entry.
  590. *
  591. * \return true if the entry is for a subdirectory else false.
  592. */
  593. static inline uint8_t DIR_IS_SUBDIR(const dir_t* dir) {
  594. return (dir->attributes & DIR_ATT_FILE_TYPE_MASK) == DIR_ATT_DIRECTORY;
  595. }
  596. /** Directory entry is for a file or subdirectory
  597. * \param[in] dir Pointer to a directory entry.
  598. *
  599. * \return true if the entry is for a normal file or subdirectory else false.
  600. */
  601. static inline uint8_t DIR_IS_FILE_OR_SUBDIR(const dir_t* dir) {
  602. return (dir->attributes & DIR_ATT_VOLUME_ID) == 0;
  603. }
  604. /** date field for FAT directory entry
  605. * \param[in] year [1980,2107]
  606. * \param[in] month [1,12]
  607. * \param[in] day [1,31]
  608. *
  609. * \return Packed date for dir_t entry.
  610. */
  611. static inline uint16_t FAT_DATE(uint16_t year, uint8_t month, uint8_t day) {
  612. return (year - 1980) << 9 | month << 5 | day;
  613. }
  614. /** year part of FAT directory date field
  615. * \param[in] fatDate Date in packed dir format.
  616. *
  617. * \return Extracted year [1980,2107]
  618. */
  619. static inline uint16_t FAT_YEAR(uint16_t fatDate) {
  620. return 1980 + (fatDate >> 9);
  621. }
  622. /** month part of FAT directory date field
  623. * \param[in] fatDate Date in packed dir format.
  624. *
  625. * \return Extracted month [1,12]
  626. */
  627. static inline uint8_t FAT_MONTH(uint16_t fatDate) {
  628. return (fatDate >> 5) & 0XF;
  629. }
  630. /** day part of FAT directory date field
  631. * \param[in] fatDate Date in packed dir format.
  632. *
  633. * \return Extracted day [1,31]
  634. */
  635. static inline uint8_t FAT_DAY(uint16_t fatDate) {
  636. return fatDate & 0X1F;
  637. }
  638. /** time field for FAT directory entry
  639. * \param[in] hour [0,23]
  640. * \param[in] minute [0,59]
  641. * \param[in] second [0,59]
  642. *
  643. * \return Packed time for dir_t entry.
  644. */
  645. static inline uint16_t FAT_TIME(uint8_t hour, uint8_t minute, uint8_t second) {
  646. return hour << 11 | minute << 5 | second >> 1;
  647. }
  648. /** hour part of FAT directory time field
  649. * \param[in] fatTime Time in packed dir format.
  650. *
  651. * \return Extracted hour [0,23]
  652. */
  653. static inline uint8_t FAT_HOUR(uint16_t fatTime) {
  654. return fatTime >> 11;
  655. }
  656. /** minute part of FAT directory time field
  657. * \param[in] fatTime Time in packed dir format.
  658. *
  659. * \return Extracted minute [0,59]
  660. */
  661. static inline uint8_t FAT_MINUTE(uint16_t fatTime) {
  662. return(fatTime >> 5) & 0X3F;
  663. }
  664. /** second part of FAT directory time field
  665. * Note second/2 is stored in packed time.
  666. *
  667. * \param[in] fatTime Time in packed dir format.
  668. *
  669. * \return Extracted second [0,58]
  670. */
  671. static inline uint8_t FAT_SECOND(uint16_t fatTime) {
  672. return 2*(fatTime & 0X1F);
  673. }
  674. /** Default date for file timestamps is 1 Jan 2000 */
  675. uint16_t const FAT_DEFAULT_DATE = ((2000 - 1980) << 9) | (1 << 5) | 1;
  676. /** Default time for file timestamp is 1 am */
  677. uint16_t const FAT_DEFAULT_TIME = (1 << 11);
  678. #endif // FatStructs_h