ra8_fs_fat_types_internal.h File Reference

Cross-TU on-disk-layout enums and typedefs for the FAT/exFAT adapter. More...

#include <stddef.h>
#include <stdint.h>
#include "ra8_attributes.h"
#include "ra8_fs.h"

Include dependency graph for ra8_fs_fat_types_internal.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	dir_walk_t
	Internal cursor used by the directory iterator. More...
struct	dir_loc_t
	Identifies the directory a lookup/scan should operate in. More...
struct	lfn_state_t
	In-progress reassembly of one LFN chain across the directory scan. More...
struct	dir_pos_t
	The on-disk address of one 32-byte directory slot. More...
struct	dir_slot_t
	A directory cursor that addresses one entry, not just one sector. More...
struct	dir_target_t
	One resolved directory entry: where it is, and what is in it. More...
struct	dir_insert_t
	Everything decided about a new directory entry before anything is written. More...
struct	exfat_cursor_t
	Linear cursor over a directory's 32-byte entries. More...
struct	exfat_dir_t
	Identifies the exFAT directory a lookup, scan or link operates in. More...
struct	exfat_setpos_t
	Directory position (cluster + entry index) of one 32-byte entry. More...
struct	ra8_fs_fmt_geom_t
	Computed on-disk geometry for one ra8_fs_format() run. More...

Enumerations
enum	ra8_fs_bpb_off_t : uint16_t {   k_bpb_off_bytes_per_sec = 11 ,   k_bpb_off_sec_per_clus = 13 ,   k_bpb_off_rsvd_sec_cnt = 14 ,   k_bpb_off_num_fats = 16 ,   k_bpb_off_root_ent_cnt = 17 ,   k_bpb_off_tot_sec_16 = 19 ,   k_bpb_off_fat_sz_16 = 22 ,   k_bpb_off_tot_sec_32 = 32 ,   k_bpb_off_fat_sz_32 = 36 ,   k_bpb_off_root_clus = 44 ,   k_bpb_off_signature_lo = 510 ,   k_bpb_off_signature_hi = 511 }
	Byte offsets inside a 512-byte BPB / boot sector. More...
enum	ra8_fs_dir_off_t : uint8_t {   k_dir_off_name = 0 ,   k_dir_off_attr = 11 ,   k_dir_off_ntres = 12 ,   k_dir_off_fst_clus_hi = 20 ,   k_dir_off_fst_clus_lo = 26 ,   k_dir_off_file_size = 28 ,   k_dir_name_field_len = 11 }
	Byte offsets inside a 32-byte FAT directory entry. More...
enum	ra8_fs_ntres_t : uint8_t {   k_ntres_base_lower = 0x08U ,   k_ntres_ext_lower = 0x10U }
	The two case flags Windows keeps in DIR_NTRes (byte 12). More...
enum	ra8_fs_dir_marker_t : uint8_t {   k_dir_marker_free_perm = 0x00 ,   k_dir_marker_free_used = 0xE5 ,   k_dir_marker_kanji_e5 = 0x05 ,   k_dir_marker_dot = 0x2E }
	Special markers in DIR_Name[0]. More...
enum	ra8_fs_sig_t : uint8_t {   k_bpb_sig_lo = 0x55 ,   k_bpb_sig_hi = 0xAA }
	Required boot-sector signature bytes (0x55 0xAA at off 510..511). More...
enum	ra8_fs_mbr_off_t : uint16_t {   k_mbr_off_part0_type = 0x1C2U ,   k_mbr_off_part0_lba = 0x1C6U ,   k_mbr_part_entry_stride = 16U ,   k_mbr_part_entry_count = 4U }
	Byte offsets inside an MBR partition table (when LBA 0 is not a BPB). More...
enum	ra8_fs_gpt_t : uint16_t {   k_gpt_part_type_protective = 0xEEU ,   k_gpt_header_lba = 1U ,   k_gpt_sig_len = 8U ,   k_gpt_off_entry_lba = 0x48U ,   k_gpt_off_entry_count = 0x50U ,   k_gpt_off_entry_size = 0x54U ,   k_gpt_entry_bytes = 128U ,   k_gpt_entry_scan_max = 128U ,   k_gpt_entry_off_first_lba = 0x20U ,   k_gpt_guid_len = 16U }
	GPT on-disk constants (UEFI spec 2.10 ch 5 "GUID Partition Table"). More...
enum	ra8_fs_exfat_off_t : uint16_t {   k_exfat_off_fsname = 3 ,   k_exfat_off_fat_lba = 0x50 ,   k_exfat_off_fat_len = 0x54 ,   k_exfat_off_heap_lba = 0x58 ,   k_exfat_off_clus_count = 0x5C ,   k_exfat_off_root_clus = 0x60 ,   k_exfat_off_bps_shift = 0x6C ,   k_exfat_off_spc_shift = 0x6D ,   k_exfat_off_num_fats = 0x6E ,   k_exfat_strm_off_flags = 1 ,   k_exfat_strm_off_nlen = 3 ,   k_exfat_strm_off_vlen_hi = 0x0C ,   k_exfat_strm_off_clus = 0x14 ,   k_exfat_strm_off_dlen = 0x18 ,   k_exfat_strm_off_dlen_hi = 0x1C ,   k_exfat_name_off = 2 ,   k_exfat_upc_off_csum = 4 }
	Byte offsets in the exFAT boot sector (VBR) and directory entries. More...
enum	ra8_fs_exfat_val_t : uint32_t {   k_exfat_entry_eod = 0x00U ,   k_exfat_entry_bitmap = 0x81U ,   k_exfat_entry_file = 0x85U ,   k_exfat_entry_stream = 0xC0U ,   k_exfat_entry_name = 0xC1U ,   k_exfat_secflag_no_fat = 0x02U ,   k_exfat_secflag_poss = 0x01U ,   k_exfat_secflag_alloc = 0x03U ,   k_exfat_attr_read_only = 0x01U ,   k_exfat_attr_directory = 0x10U ,   k_exfat_attr_archive = 0x20U ,   k_exfat_fsname_len = 8U ,   k_exfat_name_per_entry = 15U ,   k_exfat_entry_bytes = 32U ,   k_exfat_bps_shift_min = 9U ,   k_exfat_bps_shift_max = 12U ,   k_exfat_scan_limit = 65536U ,   k_exfat_name_cap = 64U ,   k_exfat_name_u8_cap = 193U ,   k_exfat_upc_words = 2918U ,   k_exfat_upc_run_tag = 0xFFFFU ,   k_exfat_csum_hi_bit = 0x8000U ,   k_exfat_off_file_secnt = 1U ,   k_exfat_off_file_csum = 2U ,   k_exfat_off_file_attr = 4U ,   k_exfat_off_strm_hash = 4U ,   k_exfat_off_strm_valid = 8U ,   k_exfat_bit_mask = 7U ,   k_exfat_bit_shift = 3U ,   k_exfat_inuse_bit = 0x80U ,   k_exfat_max_set_bytes = 224U ,   k_exfat_path_depth = 32U ,   k_exfat_dir_grow_max = 2U }
	exFAT entry-type tags + small magic values used by the reader. More...
enum	ra8_fs_exfat_fmt_off_t : uint16_t {   k_exfat_foff_jump = 0U ,   k_exfat_foff_part_off = 64U ,   k_exfat_foff_vol_len = 72U ,   k_exfat_foff_serial = 100U ,   k_exfat_foff_fs_rev = 104U ,   k_exfat_foff_vol_flags = 106U ,   k_exfat_foff_drive = 111U ,   k_exfat_foff_percent = 112U ,   k_exfat_foff_ext_sig = 508U ,   k_exfat_foff_boot_sig = 510U ,   k_exfat_de_second = 32U ,   k_exfat_de_third = 64U ,   k_exfat_de_first_clus = 20U ,   k_exfat_de_data_len = 24U ,   k_exfat_de_upc_csum = 4U ,   k_exfat_de_lbl_cnt = 1U ,   k_exfat_de_lbl_name = 2U }
	VBR + directory-entry byte offsets written by the exFAT formatter. More...
enum	ra8_fs_exfat_fmt_val_t : uint32_t {   k_exfat_entry_upcase = 0x82U ,   k_exfat_entry_label = 0x83U ,   k_exfat_fmt_jump0 = 0xEBU ,   k_exfat_fmt_jump1 = 0x76U ,   k_exfat_fmt_jump2 = 0x90U ,   k_exfat_fmt_fs_rev = 0x0100U ,   k_exfat_fmt_drive = 0x80U ,   k_exfat_fmt_percent = 0U ,   k_exfat_fmt_boot_sig = 0xAA55U ,   k_exfat_fmt_ext_sig = 0xAA550000U ,   k_exfat_fmt_fat_media = 0xFFFFFFF8U ,   k_exfat_fmt_fat_eoc = 0xFFFFFFFFU ,   k_exfat_fmt_first_clus = 2U ,   k_exfat_fmt_num_fats = 1U ,   k_exfat_fmt_boot_secs = 24U ,   k_exfat_fmt_backup_lba = 12U ,   k_exfat_fmt_ext_first = 1U ,   k_exfat_fmt_ext_count = 8U ,   k_exfat_fmt_oem_lba = 9U ,   k_exfat_fmt_resv_lba = 10U ,   k_exfat_fmt_csum_lba = 11U ,   k_exfat_fmt_csum_skip0 = 106U ,   k_exfat_fmt_csum_skip1 = 107U ,   k_exfat_fmt_csum_skip2 = 112U ,   k_exfat_fmt_csum_hibit = 0x80000000U ,   k_exfat_fmt_min_sectors = 65536U ,   k_exfat_fmt_thr_256m = 524288U ,   k_exfat_fmt_thr_32g = 67108864U ,   k_exfat_fmt_thr_256g = 536870912U ,   k_exfat_fmt_clus_4k = 12U ,   k_exfat_fmt_clus_32k = 15U ,   k_exfat_fmt_clus_128k = 17U ,   k_exfat_fmt_clus_256k = 18U ,   k_exfat_fmt_geom_iters = 4U ,   k_exfat_fmt_upc_std_bytes = 5836U ,   k_exfat_fmt_part_align = 1048576U ,   k_exfat_fmt_serial = 0x52A8E47AU ,   k_exfat_fmt_label_max = 11U ,   k_exfat_fmt_byte_bits = 8U ,   k_exfat_fmt_byte_full = 0xFFU }
	Magic values + geometry constants used by the exFAT formatter. More...
enum	ra8_fs_mbr_fmt_t : uint32_t {   k_mbr_fmt_disk_sig_off = 440U ,   k_mbr_fmt_part0_off = 446U ,   k_mbr_fmt_pe_boot = 0U ,   k_mbr_fmt_pe_chs_start = 1U ,   k_mbr_fmt_pe_type = 4U ,   k_mbr_fmt_pe_chs_end = 5U ,   k_mbr_fmt_pe_lba = 8U ,   k_mbr_fmt_pe_nsect = 12U ,   k_mbr_fmt_boot_none = 0x00U ,   k_mbr_fmt_type_exfat = 0x07U ,   k_mbr_fmt_chs_heads = 255U ,   k_mbr_fmt_chs_spt = 63U ,   k_mbr_fmt_chs_max = 16450560U ,   k_mbr_fmt_chs_ovf_h = 0xFEU ,   k_mbr_fmt_chs_ovf_m = 0xFFU ,   k_mbr_fmt_chs_ovf_l = 0xFFU ,   k_mbr_fmt_chs_sec_mask = 0x3FU ,   k_mbr_fmt_chs_cyl_hi_mask = 0x300U ,   k_mbr_fmt_chs_cyl_hi_shift = 2U ,   k_mbr_fmt_disk_sig_base = 0x1A2B3C4DU }
	Byte offsets, field strides, and CHS constants for the MBR the exFAT formatter writes at LBA 0. More...
enum	ra8_fs_cluster_t : uint32_t {   k_cluster_first_data = 2 ,   k_cluster_eoc_min_fat12 = 0x0FF8 ,   k_cluster_eoc_min_fat16 = 0xFFF8 ,   k_cluster_eoc_min_fat32 = 0x0FFFFFF8 ,   k_cluster_mask_fat32 = 0x0FFFFFFFU ,   k_cluster_eoc_min_exfat = 0xFFFFFFF8U ,   k_cluster_eoc_write_fat12 = 0x0FFF ,   k_cluster_eoc_write_fat16 = 0xFFFF ,   k_cluster_eoc_write_fat32 = 0x0FFFFFFFU ,   k_cluster_eoc_write_exfat = 0xFFFFFFFFU ,   k_cluster_free = 0 ,   k_cluster_count_fat12_max = 4085 ,   k_cluster_count_fat16_max = 65525 ,   k_fat12_value_mask = 0x0FFFU ,   k_fat12_low_nibble_mask = 0x000FU ,   k_fat12_high_nibble_mask = 0xF000U }
	Reserved cluster numbers used by the FAT itself. More...
enum	ra8_fs_fmt_off_t : uint16_t {   k_fmt_off_jmp0 = 0 ,   k_fmt_off_jmp1 = 1 ,   k_fmt_off_jmp2 = 2 ,   k_fmt_off_oem = 3 ,   k_fmt_off_media = 21 ,   k_fmt_off_sec_per_trk = 24 ,   k_fmt_off_num_heads = 26 ,   k_fmt_off_f16_drvnum = 36 ,   k_fmt_off_f16_bootsig = 38 ,   k_fmt_off_f16_volid = 39 ,   k_fmt_off_f16_label = 43 ,   k_fmt_off_f16_fstype = 54 ,   k_fmt_off_f32_fsinfo = 48 ,   k_fmt_off_f32_bkboot = 50 ,   k_fmt_off_f32_drvnum = 64 ,   k_fmt_off_f32_bootsig = 66 ,   k_fmt_off_f32_volid = 67 ,   k_fmt_off_f32_label = 71 ,   k_fmt_off_f32_fstype = 82 ,   k_fmt_fsi_off_lead = 0 ,   k_fmt_fsi_off_struct = 484 ,   k_fmt_fsi_off_free = 488 ,   k_fmt_fsi_off_nxtfree = 492 ,   k_fmt_fsi_off_trail = 508 }
	Extra BPB byte offsets written only by the formatter (ra8_fs_format). More...
enum	ra8_fs_fmt_val_t : uint32_t {   k_fmt_jmp_byte0 = 0xEBU ,   k_fmt_jmp_byte1 = 0x58U ,   k_fmt_jmp_byte2 = 0x90U ,   k_fmt_media_fixed = 0xF8U ,   k_fmt_drvnum_hd = 0x80U ,   k_fmt_ext_bootsig = 0x29U ,   k_fmt_sec_per_trk = 63U ,   k_fmt_num_heads = 255U ,   k_fmt_num_fats = 2U ,   k_fmt_root_ents_f16 = 512U ,   k_fmt_resv_f16 = 1U ,   k_fmt_resv_f32 = 32U ,   k_fmt_root_clus_f32 = 2U ,   k_fmt_fsinfo_sector = 1U ,   k_fmt_bkboot_sector = 6U ,   k_fmt_volid_base = 0x52A8D200U ,   k_fmt_fsi_lead_sig = 0x41615252U ,   k_fmt_fsi_struct_sig = 0x61417272U ,   k_fmt_fsi_trail_sig = 0xAA550000U ,   k_fmt_label_len = 11U ,   k_fmt_spc_max = 64U ,   k_fmt_zero_chunk_bytes = 16384U ,   k_fmt_fat32_entry_bytes = 4U ,   k_fmt_fat16_entry_bytes = 2U ,   k_fmt_fat32_clus_cap = 0x0FFFFFF0U ,   k_fmt_fsi_unknown = 0xFFFFFFFFU ,   k_fmt_fat32_nxt_free = 3U ,   k_fmt_f32_thr_260m = 532480U ,   k_fmt_f32_thr_8g = 16777216U ,   k_fmt_f32_thr_16g = 33554432U ,   k_fmt_f32_thr_32g = 67108864U ,   k_fmt_f32_clus_512b = 9U ,   k_fmt_f32_clus_4k = 12U ,   k_fmt_f32_clus_8k = 13U ,   k_fmt_f32_clus_16k = 14U ,   k_fmt_f32_clus_32k = 15U }
	Magic values + geometry limits used by the formatter (ra8_fs_format). More...
enum	ra8_fs_misc_t : uint16_t {   k_byte_mask = 0xFFU ,   k_shift_byte = 8 ,   k_shift_two_bytes = 16 ,   k_shift_three_bytes = 24 ,   k_shift_nibble = 4 ,   k_shift_word32 = 32 ,   k_nibble_mask = 0x0F ,   k_byte_mask_full = 0xFF ,   k_word_mask = 0xFFFFU ,   k_max_8_3_name = 11 ,   k_dot_pos = 8 ,   k_filename_base_len = 8 ,   k_filename_ext_len = 3 ,   k_path_max = 64 }
	Misc small constants used by parsing/formatting code. More...
enum	ra8_fs_lfn_t : uint32_t {   k_lfn_off_seq = 0U ,   k_lfn_off_type = 12U ,   k_lfn_off_checksum = 13U ,   k_lfn_off_clus_lo = 26U ,   k_lfn_seq_order_mask = 0x1FU ,   k_lfn_seq_last = 0x40U ,   k_lfn_chars_per_ent = 13U ,   k_lfn_max_entries = 19U ,   k_lfn_utf8_cap = 742U ,   k_lfn_unicode_pad = 0xFFFFU ,   k_sfn_csum_high_bit = 0x80U ,   k_lfn_write_max = 247U ,   k_lfn_erase_max = 20U ,   k_lfn_alias_tail_max = 999999U ,   k_lfn_alias_base_max = 6U }
	LFN directory-entry field offsets, sequence masks, and reassembly caps. More...
enum	ra8_fs_name_kind_t : uint8_t {   k_name_kind_invalid = 0U ,   k_name_kind_short = 1U ,   k_name_kind_long = 2U }
	How a leaf component has to be stored in a FAT directory. More...
enum	exfat_set_const_t : uint32_t {   k_exfat_set_max_entries = 19U ,   k_exfat_set_writable = 7U ,   k_exfat_set_min_entries = 3U }
	Bounds on one exFAT directory entry set. More...
enum	ra8_fs_sec_role_t : uint8_t {   k_fs_sec_role_walk = 0U ,   k_fs_sec_role_fat = 1U ,   k_fs_sec_role_fat2 = 2U ,   k_fs_sec_role_io = 3U ,   k_fs_sec_roles = 4U }
	Index of each fixed-role sector buffer in the arena (#683). More...

Variables
uint8_t	g_fs_scratch [k_ra8_fs_sector_max]
	Single max-sector scratch buffer reused across all I/O.

Detailed Description

Cross-TU on-disk-layout enums and typedefs for the FAT/exFAT adapter.

The TYPES half of the FAT/exFAT adapter's module-private declarations. It carries the on-disk-layout enums (BPB / directory / MBR / GPT / exFAT / formatter), the directory/format/exFAT cursor typedefs, and the one shared scratch-sector buffer. It is pulled in by the ra8_fs_fat_internal.h umbrella (and therefore by every ra8_fs_fat*.c file) and by the prototype sub-headers, whose helper declarations reference these types.

This header aggregates the module's on-disk-layout enums shared across the FAT translation units.

Copyright

Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since

0.1.0

Definition in file ra8_fs_fat_types_internal.h.

Enumeration Type Documentation

exfat_set_const_t

enum exfat_set_const_t : uint32_t

Bounds on one exFAT directory entry set.

exFAT spec sec 7.4: a File entry carries a SecondaryCount, and the set is that many 32-byte entries plus the File entry itself. This adapter's name cap (k_exfat_name_cap, 64 UTF-16 units) needs one Stream entry plus ceil(64 / 15) Name entries, so k_exfat_set_writable is the largest set it can rewrite. k_exfat_set_max_entries is the largest the FORMAT allows and bounds the walk over a set some other implementation wrote.

Invariant

k_exfat_set_writable <= k_exfat_set_max_entries.

Example:

exfat_setpos_t pos[k_exfat_set_max_entries] = {};

See also

priv_exfat_find_set()

Since

0.1.0

Enumerator
k_exfat_set_max_entries	1 File + 1 Stream + 17 Name entries.
k_exfat_set_writable	1 File + 1 Stream + 5 Name (64 chars).
k_exfat_set_min_entries	The smallest legal set: File+Stream+Name.

Definition at line 750 of file ra8_fs_fat_types_internal.h.

ra8_fs_bpb_off_t

enum ra8_fs_bpb_off_t : uint16_t

Byte offsets inside a 512-byte BPB / boot sector.

Enumerator
k_bpb_off_bytes_per_sec	MS FAT spec sec 3.1 "BPB_BytsPerSec".
k_bpb_off_sec_per_clus	MS FAT spec sec 3.1 "BPB_SecPerClus".
k_bpb_off_rsvd_sec_cnt	MS FAT spec sec 3.1 "BPB_RsvdSecCnt".
k_bpb_off_num_fats	MS FAT spec sec 3.1 "BPB_NumFATs".
k_bpb_off_root_ent_cnt	MS FAT spec sec 3.1 "BPB_RootEntCnt".
k_bpb_off_tot_sec_16	MS FAT spec sec 3.1 "BPB_TotSec16".
k_bpb_off_fat_sz_16	MS FAT spec sec 3.1 "BPB_FATSz16".
k_bpb_off_tot_sec_32	MS FAT spec sec 3.1 "BPB_TotSec32".
k_bpb_off_fat_sz_32	MS FAT spec sec 3.5 "BPB_FATSz32".
k_bpb_off_root_clus	MS FAT spec sec 3.5 "BPB_RootClus".
k_bpb_off_signature_lo	Boot sig byte 1 (0x55).
k_bpb_off_signature_hi	Boot sig byte 2 (0xAA).

Definition at line 47 of file ra8_fs_fat_types_internal.h.

ra8_fs_cluster_t

enum ra8_fs_cluster_t : uint32_t

Reserved cluster numbers used by the FAT itself.

Enumerator
k_cluster_first_data	Cluster numbers start at 2.
k_cluster_eoc_min_fat12	MS FAT spec sec 4.1 EOC threshold.
k_cluster_eoc_min_fat16	MS FAT spec sec 4.1 EOC threshold.
k_cluster_eoc_min_fat32	MS FAT spec sec 4.2 EOC threshold.
k_cluster_mask_fat32	Top 4 bits reserved on FAT32.
k_cluster_eoc_min_exfat	exFAT spec sec 4.1 EOC threshold.
k_cluster_eoc_write_fat12	Value we write to terminate.
k_cluster_eoc_write_fat16	Cluster eoc write fat16.
k_cluster_eoc_write_fat32	Cluster eoc write fat32.
k_cluster_eoc_write_exfat	exFAT spec sec 4.1 EOC marker.
k_cluster_free	Cluster free.
k_cluster_count_fat12_max	MS FAT spec sec 3.5 boundary.
k_cluster_count_fat16_max	MS FAT spec sec 3.5 boundary.
k_fat12_value_mask	12-bit FAT12 entry mask.
k_fat12_low_nibble_mask	Untouched nibble (even cluster).
k_fat12_high_nibble_mask	Untouched nibble (odd cluster).

Definition at line 349 of file ra8_fs_fat_types_internal.h.

ra8_fs_dir_marker_t

enum ra8_fs_dir_marker_t : uint8_t

Special markers in DIR_Name[0].

MS FAT spec sec 6.

Enumerator
k_dir_marker_free_perm	End-of-directory.
k_dir_marker_free_used	Slot was used, deleted.
k_dir_marker_kanji_e5	0xE5 in raw name, escaped.
k_dir_marker_dot	'. ' – a "." / ".." entry.

Definition at line 101 of file ra8_fs_fat_types_internal.h.

ra8_fs_dir_off_t

enum ra8_fs_dir_off_t : uint8_t

Byte offsets inside a 32-byte FAT directory entry.

MS FAT spec sec 6.

Enumerator
k_dir_off_name	MS FAT spec sec 6 "DIR_Name" (11 bytes).
k_dir_off_attr	MS FAT spec sec 6 "DIR_Attr".
k_dir_off_ntres	MS FAT spec sec 6 "DIR_NTRes".
k_dir_off_fst_clus_hi	MS FAT spec sec 6 "DIR_FstClusHI".
k_dir_off_fst_clus_lo	MS FAT spec sec 6 "DIR_FstClusLO".
k_dir_off_file_size	MS FAT spec sec 6 "DIR_FileSize".
k_dir_name_field_len	8 + 3 raw chars (no dot).

Definition at line 66 of file ra8_fs_fat_types_internal.h.

ra8_fs_exfat_fmt_off_t

enum ra8_fs_exfat_fmt_off_t : uint16_t

VBR + directory-entry byte offsets written by the exFAT formatter.

Companion to the reader's ra8_fs_exfat_off_t; covers the fields the reader never touches (boot signatures, serial, label entry, ...). Microsoft exFAT spec sections 3 (Main Boot Sector) and 7 (directory entries).

Enumerator
k_exfat_foff_jump	JumpBoot (3 bytes).
k_exfat_foff_part_off	PartitionOffset (64-bit).
k_exfat_foff_vol_len	VolumeLength (64-bit).
k_exfat_foff_serial	VolumeSerialNumber (32-bit).
k_exfat_foff_fs_rev	FileSystemRevision (16-bit).
k_exfat_foff_vol_flags	VolumeFlags (16-bit).
k_exfat_foff_drive	DriveSelect.
k_exfat_foff_percent	PercentInUse.
k_exfat_foff_ext_sig	ExtendedBootSignature (extended sectors).
k_exfat_foff_boot_sig	BootSignature 0xAA55 (16-bit).
k_exfat_de_second	Offset of the 2nd dir entry in a set.
k_exfat_de_third	Offset of the 3rd dir entry in a set.
k_exfat_de_first_clus	Bitmap/Up-case entry: FirstCluster.
k_exfat_de_data_len	Bitmap/Up-case entry: DataLength (64-bit).
k_exfat_de_upc_csum	Up-case entry: TableChecksum (32-bit).
k_exfat_de_lbl_cnt	Volume-label entry: CharacterCount.
k_exfat_de_lbl_name	Volume-label entry: UTF-16 label.

Definition at line 236 of file ra8_fs_fat_types_internal.h.

ra8_fs_exfat_fmt_val_t

enum ra8_fs_exfat_fmt_val_t : uint32_t

Magic values + geometry constants used by the exFAT formatter.

Enumerator
k_exfat_entry_upcase	Up-case Table directory entry.
k_exfat_entry_label	Volume Label directory entry.
k_exfat_fmt_jump0	JumpBoot byte 0.
k_exfat_fmt_jump1	JumpBoot byte 1.
k_exfat_fmt_jump2	JumpBoot byte 2.
k_exfat_fmt_fs_rev	FileSystemRevision = 1.00.
k_exfat_fmt_drive	DriveSelect (first fixed disk).
k_exfat_fmt_percent	PercentInUse = 0% (fresh volume).
k_exfat_fmt_boot_sig	BootSignature (sector 0).
k_exfat_fmt_ext_sig	ExtendedBootSignature (sectors 1-8).
k_exfat_fmt_fat_media	FatEntry[0] media descriptor.
k_exfat_fmt_fat_eoc	FatEntry end-of-chain.
k_exfat_fmt_first_clus	First cluster of the heap.
k_exfat_fmt_num_fats	exFAT uses a single FAT.
k_exfat_fmt_boot_secs	12 main + 12 backup boot sectors.
k_exfat_fmt_backup_lba	Backup boot region start.
k_exfat_fmt_ext_first	First extended boot sector.
k_exfat_fmt_ext_count	Extended boot sector count.
k_exfat_fmt_oem_lba	OEM Parameters sector.
k_exfat_fmt_resv_lba	Reserved sector.
k_exfat_fmt_csum_lba	Boot Checksum sector.
k_exfat_fmt_csum_skip0	Checksum-excluded byte: VolumeFlags.
k_exfat_fmt_csum_skip1	Checksum-excluded byte: VolumeFlags.
k_exfat_fmt_csum_skip2	Checksum-excluded byte: PercentInUse.
k_exfat_fmt_csum_hibit	Rotate-right wrap bit (32-bit).
k_exfat_fmt_min_sectors	Smallest exFAT volume: 32 MiB.
k_exfat_fmt_thr_256m	<= 256 MB -> 4 KB clusters.
k_exfat_fmt_thr_32g	<= 32 GB -> 32 KB clusters.
k_exfat_fmt_thr_256g	<= 256 GB -> 128 KB clusters.
k_exfat_fmt_clus_4k	log2 cluster BYTES for 4 KB clusters.
k_exfat_fmt_clus_32k	... 32 KB.
k_exfat_fmt_clus_128k	... 128 KB.
k_exfat_fmt_clus_256k	... 256 KB (> 256 GB cards).
k_exfat_fmt_geom_iters	Fixed-point geometry passes.
k_exfat_fmt_upc_std_bytes	Canonical Microsoft up-case table len.
k_exfat_fmt_part_align	exFAT partition alignment: 1 MiB.
k_exfat_fmt_serial	Arbitrary volume-serial base.
k_exfat_fmt_label_max	Volume-label cap (UTF-16 units).
k_exfat_fmt_byte_bits	Bits per bitmap byte.
k_exfat_fmt_byte_full	A fully-allocated bitmap byte.

Definition at line 260 of file ra8_fs_fat_types_internal.h.

ra8_fs_exfat_off_t

enum ra8_fs_exfat_off_t : uint16_t

Byte offsets in the exFAT boot sector (VBR) and directory entries.

exFAT (Microsoft exFAT spec) replaces the FAT BPB with a Volume Boot Record carrying sector-relative region offsets and log2 geometry. The directory uses 32-byte typed entry sets (File 0x85 + Stream 0xC0 + Name 0xC1) with UTF-16LE names. Read-only support; fields are little-endian.

Enumerator
k_exfat_off_fsname	"EXFAT " filesystem-name field (8 chars).
k_exfat_off_fat_lba	FatOffset (sectors from VBR).
k_exfat_off_fat_len	FatLength (sectors).
k_exfat_off_heap_lba	ClusterHeapOffset (sectors from VBR).
k_exfat_off_clus_count	ClusterCount.
k_exfat_off_root_clus	FirstClusterOfRootDirectory.
k_exfat_off_bps_shift	BytesPerSectorShift (log2).
k_exfat_off_spc_shift	SectorsPerClusterShift (log2).
k_exfat_off_num_fats	NumberOfFats.
k_exfat_strm_off_flags	Stream-ext GeneralSecondaryFlags.
k_exfat_strm_off_nlen	Stream-ext NameLength (UTF-16 units).
k_exfat_strm_off_vlen_hi	Stream-ext ValidDataLength high word.
k_exfat_strm_off_clus	Stream-ext FirstCluster.
k_exfat_strm_off_dlen	Stream-ext DataLength (low 32 used).
k_exfat_strm_off_dlen_hi	Stream-ext DataLength high word.
k_exfat_name_off	File-name entry character offset.
k_exfat_upc_off_csum	Up-case-table entry TableChecksum (32-bit).

Definition at line 167 of file ra8_fs_fat_types_internal.h.

ra8_fs_exfat_val_t

enum ra8_fs_exfat_val_t : uint32_t

exFAT entry-type tags + small magic values used by the reader.

Enumerator
k_exfat_entry_eod	End-of-directory marker.
k_exfat_entry_bitmap	Allocation-bitmap directory entry.
k_exfat_entry_file	File directory entry.
k_exfat_entry_stream	Stream-extension entry.
k_exfat_entry_name	File-name entry.
k_exfat_secflag_no_fat	GeneralSecondaryFlags: NoFatChain.
k_exfat_secflag_poss	GeneralSecondaryFlags: AllocationPossible.
k_exfat_secflag_alloc	AllocationPossible | NoFatChain.
k_exfat_attr_read_only	FileAttributes: read-only.
k_exfat_attr_directory	FileAttributes: directory.
k_exfat_attr_archive	FileAttributes: archive.
k_exfat_fsname_len	"EXFAT " field length.
k_exfat_name_per_entry	UTF-16 units per file-name entry.
k_exfat_entry_bytes	Directory entry size.
k_exfat_bps_shift_min	log2(512): smallest BytesPerSectorShift.
k_exfat_bps_shift_max	log2(4096): largest BytesPerSectorShift.
k_exfat_scan_limit	Max dir entries scanned (P10 bound).
k_exfat_name_cap	Longest name we store, in UTF-16 units.
k_exfat_name_u8_cap	That name in UTF-8: 3 * 64, plus a NUL.
k_exfat_upc_words	k_exfat_fmt_upc_std_bytes / 2.
k_exfat_upc_run_tag	Up-case table: an identity run follows.
k_exfat_csum_hi_bit	Wrap bit for the rotate-add checksum.
k_exfat_off_file_secnt	File entry: SecondaryCount.
k_exfat_off_file_csum	File entry: SetChecksum (2 bytes).
k_exfat_off_file_attr	File entry: FileAttributes (2 bytes).
k_exfat_off_strm_hash	Stream entry: NameHash (2 bytes).
k_exfat_off_strm_valid	Stream entry: ValidDataLength (8 B).
k_exfat_bit_mask	Bit index within a bitmap byte.
k_exfat_bit_shift	log2(8): cluster index -> byte.
k_exfat_inuse_bit	Directory entry type bit 7 = in use.
k_exfat_max_set_bytes	(2 + ceil(64/15)) * 32 = 7 entries.
k_exfat_path_depth	Max nested components per exFAT path.
k_exfat_dir_grow_max	Max clusters one find-space call appends.

Definition at line 191 of file ra8_fs_fat_types_internal.h.

ra8_fs_fmt_off_t

enum ra8_fs_fmt_off_t : uint16_t

Extra BPB byte offsets written only by the formatter (ra8_fs_format).

Complements ra8_fs_bpb_off_t (the read path) with the boot-prologue, media, extended-signature, label, and filesystem-type fields that the mount path never reads but a valid on-disk volume must carry. Offsets follow Microsoft "FAT: General Overview of On-Disk Format" sec 3.

Enumerator
k_fmt_off_jmp0	Jump-boot byte 0 (0xEB).
k_fmt_off_jmp1	Jump-boot byte 1 (offset).
k_fmt_off_jmp2	Jump-boot byte 2 (0x90 NOP).
k_fmt_off_oem	OEM name field (8 bytes).
k_fmt_off_media	BPB_Media descriptor.
k_fmt_off_sec_per_trk	BPB_SecPerTrk.
k_fmt_off_num_heads	BPB_NumHeads.
k_fmt_off_f16_drvnum	FAT12/16 BS_DrvNum.
k_fmt_off_f16_bootsig	FAT12/16 BS_BootSig (0x29).
k_fmt_off_f16_volid	FAT12/16 BS_VolID (4 bytes).
k_fmt_off_f16_label	FAT12/16 BS_VolLab (11 bytes).
k_fmt_off_f16_fstype	FAT12/16 BS_FilSysType (8 bytes).
k_fmt_off_f32_fsinfo	FAT32 BPB_FSInfo sector number.
k_fmt_off_f32_bkboot	FAT32 BPB_BkBootSec (backup boot).
k_fmt_off_f32_drvnum	FAT32 BS_DrvNum.
k_fmt_off_f32_bootsig	FAT32 BS_BootSig (0x29).
k_fmt_off_f32_volid	FAT32 BS_VolID (4 bytes).
k_fmt_off_f32_label	FAT32 BS_VolLab (11 bytes).
k_fmt_off_f32_fstype	FAT32 BS_FilSysType (8 bytes).
k_fmt_fsi_off_lead	FSInfo FSI_LeadSig offset.
k_fmt_fsi_off_struct	FSInfo FSI_StrucSig offset.
k_fmt_fsi_off_free	FSInfo FSI_Free_Count offset.
k_fmt_fsi_off_nxtfree	FSInfo FSI_Nxt_Free offset.
k_fmt_fsi_off_trail	FSInfo FSI_TrailSig offset.

Definition at line 377 of file ra8_fs_fat_types_internal.h.

ra8_fs_fmt_val_t

enum ra8_fs_fmt_val_t : uint32_t

Magic values + geometry limits used by the formatter (ra8_fs_format).

Enumerator
k_fmt_jmp_byte0	Short jump opcode.
k_fmt_jmp_byte1	Jump displacement (to +0x5A).
k_fmt_jmp_byte2	NOP padding.
k_fmt_media_fixed	Media descriptor: non-removable.
k_fmt_drvnum_hd	BS_DrvNum: first fixed disk.
k_fmt_ext_bootsig	Extended boot signature present.
k_fmt_sec_per_trk	Conventional CHS sectors/track.
k_fmt_num_heads	Conventional CHS heads.
k_fmt_num_fats	Two FAT copies, like every mkfs.
k_fmt_root_ents_f16	FAT12/16 root-directory entries.
k_fmt_resv_f16	FAT12/16 reserved (boot) sectors.
k_fmt_resv_f32	FAT32 reserved sectors.
k_fmt_root_clus_f32	FAT32 root directory cluster.
k_fmt_fsinfo_sector	FAT32 FSInfo sector LBA.
k_fmt_bkboot_sector	FAT32 backup boot sector LBA.
k_fmt_volid_base	Arbitrary volume-serial base.
k_fmt_fsi_lead_sig	FSInfo lead signature "RRaA".
k_fmt_fsi_struct_sig	FSInfo struct signature "rrAa".
k_fmt_fsi_trail_sig	FSInfo trailing signature.
k_fmt_label_len	Volume-label field width (bytes).
k_fmt_spc_max	Largest sectors-per-cluster we set.
k_fmt_zero_chunk_bytes	Zero-fill bounce buffer size.
k_fmt_fat32_entry_bytes	Bytes per FAT32 FAT entry.
k_fmt_fat16_entry_bytes	Bytes per FAT16 (and FAT12-sizing) entry.
k_fmt_fat32_clus_cap	Max FAT32 cluster count we accept.
k_fmt_fsi_unknown	FSInfo free-count "unknown".
k_fmt_fat32_nxt_free	First allocatable FAT32 cluster.
k_fmt_f32_thr_260m	<= 260 MB -> 512 B clusters.
k_fmt_f32_thr_8g	<= 8 GB -> 4 KB clusters.
k_fmt_f32_thr_16g	<= 16 GB -> 8 KB clusters.
k_fmt_f32_thr_32g	<= 32 GB -> 16 KB clusters.
k_fmt_f32_clus_512b	log2(512): <= 260 MB cards.
k_fmt_f32_clus_4k	log2(4 KB): <= 8 GB cards.
k_fmt_f32_clus_8k	log2(8 KB): <= 16 GB cards.
k_fmt_f32_clus_16k	log2(16 KB): <= 32 GB cards.
k_fmt_f32_clus_32k	log2(32 KB): > 32 GB cards.

Definition at line 408 of file ra8_fs_fat_types_internal.h.

ra8_fs_gpt_t

enum ra8_fs_gpt_t : uint16_t

GPT on-disk constants (UEFI spec 2.10 ch 5 "GUID Partition Table").

A GPT disk carries a protective MBR (partition 0 type 0xEE), the GPT header at LBA 1 ("EFI PART"), and a partition entry array (128-byte entries). FAT/exFAT data volumes live in entries whose type GUID is Microsoft Basic Data; macOS additionally creates an EFI System Partition first, which must be skipped to reach the user volume.

Enumerator
k_gpt_part_type_protective	MBR type byte for a GPT disk.
k_gpt_header_lba	GPT header location.
k_gpt_sig_len	"EFI PART" signature length.
k_gpt_off_entry_lba	Entry-array first LBA (8 bytes LE).
k_gpt_off_entry_count	Number of partition entries.
k_gpt_off_entry_size	Bytes per partition entry.
k_gpt_entry_bytes	Standard entry size supported.
k_gpt_entry_scan_max	Bounded entry walk (UEFI minimum).
k_gpt_entry_off_first_lba	Entry: first LBA (8 bytes LE).
k_gpt_guid_len	Type-GUID length in an entry.

Definition at line 145 of file ra8_fs_fat_types_internal.h.

ra8_fs_lfn_t

enum ra8_fs_lfn_t : uint32_t

LFN directory-entry field offsets, sequence masks, and reassembly caps.

Enumerator
k_lfn_off_seq	Sequence/order byte (LDIR_Ord).
k_lfn_off_type	LDIR_Type – zero for a name component.
k_lfn_off_checksum	Checksum of the matching 8.3 name.
k_lfn_off_clus_lo	LDIR_FstClusLO – must be written as 0.
k_lfn_seq_order_mask	Order = seq & 0x1F (1..20).
k_lfn_seq_last	Set on the last logical group.
k_lfn_chars_per_ent	UTF-16 chars carried per LFN entry.
k_lfn_max_entries	Cap so 19*13 = 247 chars fits the buffer.
k_lfn_utf8_cap	A 247-unit name in UTF-8: 3 * 247, + NUL.
k_lfn_unicode_pad	Slot padding past the name terminator.
k_sfn_csum_high_bit	Rotate-in bit when the running sum is odd.
k_lfn_write_max	Longest name we WRITE (k_lfn_max_entries).
k_lfn_erase_max	Longest chain we ERASE (spec LDIR_Ord max).
k_lfn_alias_tail_max	Highest ~N probed by the alias generator.
k_lfn_alias_base_max	Basis chars kept ahead of a one-digit ~N.

Definition at line 514 of file ra8_fs_fat_types_internal.h.

ra8_fs_mbr_fmt_t

enum ra8_fs_mbr_fmt_t : uint32_t

Byte offsets, field strides, and CHS constants for the MBR the exFAT formatter writes at LBA 0.

A PC expects removable media to carry a partition table, not a "superfloppy" volume at sector 0. The exFAT formatter therefore lays a classic DOS/MBR partition table (disk signature at 440, one primary partition entry at 446, the 0x55AA boot signature) with a single type-0x07 (exFAT/NTFS) partition aligned at ::k_exfat_fmt_part_lba. The legacy CHS fields are filled from the conventional 255-head / 63-sector geometry (or the 0xFE/0xFF/0xFF "beyond CHS, use LBA" sentinel above k_mbr_fmt_chs_max) so fdisk/sfdisk report the partition without a CHS-mismatch warning.

Enumerator
k_mbr_fmt_disk_sig_off	MBR disk signature (4 bytes LE).
k_mbr_fmt_part0_off	First partition-table entry.
k_mbr_fmt_pe_boot	Entry: boot flag (relative).
k_mbr_fmt_pe_chs_start	Entry: start CHS (3 bytes).
k_mbr_fmt_pe_type	Entry: partition type byte.
k_mbr_fmt_pe_chs_end	Entry: end CHS (3 bytes).
k_mbr_fmt_pe_lba	Entry: first LBA (4 bytes LE).
k_mbr_fmt_pe_nsect	Entry: sector count (4 bytes LE).
k_mbr_fmt_boot_none	Non-bootable partition.
k_mbr_fmt_type_exfat	Partition type: exFAT/NTFS/HPFS.
k_mbr_fmt_chs_heads	Conventional heads-per-cylinder.
k_mbr_fmt_chs_spt	Conventional sectors-per-track.
k_mbr_fmt_chs_max	1024*255*63: first LBA past CHS.
k_mbr_fmt_chs_ovf_h	Overflow CHS head byte.
k_mbr_fmt_chs_ovf_m	Overflow CHS sector/cyl-hi byte.
k_mbr_fmt_chs_ovf_l	Overflow CHS cylinder-low byte.
k_mbr_fmt_chs_sec_mask	Low 6 bits of the CHS sector byte.
k_mbr_fmt_chs_cyl_hi_mask	Cylinder bits [9:8] before packing.
k_mbr_fmt_chs_cyl_hi_shift	Shift packing cyl[9:8] into bits[7:6].
k_mbr_fmt_disk_sig_base	Arbitrary disk-signature base.

Definition at line 322 of file ra8_fs_fat_types_internal.h.

ra8_fs_mbr_off_t

enum ra8_fs_mbr_off_t : uint16_t

Byte offsets inside an MBR partition table (when LBA 0 is not a BPB).

A standard SD card is MBR-partitioned: LBA 0 holds a partition table (four 16-byte entries starting at 0x1BE) and the FAT boot sector lives at the partition's first LBA. Entry 0's type and first-LBA are named directly; entries 1-3 are reached by adding k_mbr_part_entry_stride, so the auto path (partition 0) and ra8_fs_mount_partition (any of 0-3) share one set of offsets.

Enumerator
k_mbr_off_part0_type	Partition 0 type byte (0 = unused).
k_mbr_off_part0_lba	Partition 0 first-LBA (4 bytes, LE).
k_mbr_part_entry_stride	Bytes between primary partition entries.
k_mbr_part_entry_count	Primary partition entries in an MBR.

Definition at line 128 of file ra8_fs_fat_types_internal.h.

ra8_fs_misc_t

enum ra8_fs_misc_t : uint16_t

Misc small constants used by parsing/formatting code.

Enumerator
k_byte_mask	Byte mask.
k_shift_byte	Shift byte.
k_shift_two_bytes	Shift two bytes.
k_shift_three_bytes	Shift three bytes.
k_shift_nibble	Shift nibble.
k_shift_word32	Shift a whole 32-bit word (u64 halves).
k_nibble_mask	Nibble mask.
k_byte_mask_full	Byte mask full.
k_word_mask	Word mask.
k_max_8_3_name	8.3 packed length without dot.
k_dot_pos	In an 8.3 packed name, dot would go here.
k_filename_base_len	Filename base length.
k_filename_ext_len	Filename ext length.
k_path_max	Path maximum.

Definition at line 458 of file ra8_fs_fat_types_internal.h.

ra8_fs_name_kind_t

enum ra8_fs_name_kind_t : uint8_t

How a leaf component has to be stored in a FAT directory.

Three answers, because there are three on-disk shapes: a name that is already an 8.3 name occupies one slot; a name that differs from one only in case occupies one slot plus a DIR_NTRes bit; and anything else needs a VFAT chain plus a generated ~N alias. The distinction is made once, by priv_name_classify(), so that open, mkdir and rename cannot disagree about it.

Invariant

k_name_kind_short implies the packed 8.3 output is valid.

See also

priv_name_classify()

Since

0.1.0

Enumerator
k_name_kind_invalid	Empty, over-long, or holds an illegal character.
k_name_kind_short	Fits 8.3; store one entry (+ NTRes case bits).
k_name_kind_long	Needs a VFAT chain and a generated ~N alias.

Definition at line 574 of file ra8_fs_fat_types_internal.h.

ra8_fs_ntres_t

enum ra8_fs_ntres_t : uint8_t

The two case flags Windows keeps in DIR_NTRes (byte 12).

A name that differs from its 8.3 form only by being lower case needs no long-name chain at all: the entry stores the upper-case form and sets one or both of these bits, and every reader that knows them renders data.log rather than DATA.LOG. The bits are not in the Microsoft FAT specification's field table – it reserves the byte – but they are what every Windows, Linux and macOS driver writes and reads, so they are the interoperable encoding.

Invariant

The two bits are independent; either, both, or neither may be set.

See also

priv_name_classify()

Since

0.1.0

Enumerator
k_ntres_base_lower	Render DIR_Name[0..7] lower case.
k_ntres_ext_lower	Render DIR_Name[8..10] lower case.

Definition at line 92 of file ra8_fs_fat_types_internal.h.

ra8_fs_sec_role_t

enum ra8_fs_sec_role_t : uint8_t

Index of each fixed-role sector buffer in the arena (#683).

One row per role in the discipline documented in ra8_fs_fat_bytes_internal.h; k_fs_sec_roles sizes the backing array.

Invariant

k_fs_sec_roles is the count of role rows above it.

See also

priv_sec_walk()

Since

0.1.0

Enumerator
k_fs_sec_role_walk	Directory scans and entry read-modify-write.
k_fs_sec_role_fat	The sector holding a FAT entry.
k_fs_sec_role_fat2	FAT12 straddle: the following sector.
k_fs_sec_role_io	Leaf data / bitmap sector transfers.
k_fs_sec_roles	Arena row count.

Definition at line 818 of file ra8_fs_fat_types_internal.h.

ra8_fs_sig_t

enum ra8_fs_sig_t : uint8_t

Required boot-sector signature bytes (0x55 0xAA at off 510..511).

Enumerator
k_bpb_sig_lo	Bpb sig lo.
k_bpb_sig_hi	Bpb sig hi.

Definition at line 112 of file ra8_fs_fat_types_internal.h.

Variable Documentation

g_fs_scratch

uint8_t g_fs_scratch[k_ra8_fs_sector_max]

extern

Single max-sector scratch buffer reused across all I/O.

Shared by every FAT/exFAT translation unit; declared extern in ra8_fs_fat_internal.h and defined here exactly once. Sized to k_ra8_fs_sector_max so a 4Kn medium fits without allocation.

One module-wide bounce buffer for every BPB, FAT, directory, and data-sector access. Sized to k_ra8_fs_sector_max so a 4Kn medium fits; a 512-byte mount simply uses the first quarter. Defined once in ra8_fs_fat_mount.c.

Note

Not reentrant; the adapter is single-threaded by contract.

Warning

Do not access concurrently; callers serialise all FS operations.

Since

0.1.0

Definition at line 40 of file ra8_fs_fat_mount.c.

Referenced by internal_exfat_write_bitmap(), internal_exfat_write_boot(), internal_exfat_write_boot_tail(), internal_exfat_write_fat(), internal_exfat_write_mbr(), internal_exfat_write_root(), internal_fmt_seed_fats(), internal_fmt_write_fsinfo(), internal_gpt_read_geom(), internal_gpt_scan_entries(), internal_locate_indexed(), internal_read_boot_sector(), priv_exfat_write_upcase(), priv_gpt_locate_partition(), priv_parse_bpb_into_mount(), and priv_parse_volume().