Hadris Partition

Partition table support for MBR, GPT, and Hybrid MBR.

Overview

This crate provides read and write support for common partition table formats used in disk images and storage devices.

Features

• MBR - Legacy BIOS partition tables (4 primary partitions)
• GPT - Modern UEFI partition tables (128+ partitions with GUIDs)
• Hybrid MBR - Combined MBR+GPT for dual BIOS/UEFI boot compatibility
• No-std Compatible - Use in bootloaders and embedded systems

Feature Flags

Note: GPT header/entry CRC checks run only when the crc feature is enabled. Without it, CRC fields are ignored on read.

std selects platform integration but does not select an I/O mode. The default feature set enables sync explicitly; custom configurations should enable sync, async, or both.

Usage

Detecting and reading a partition scheme

Requires features read and alloc (included when using std + read):

use std::fs::File;
use hadris_part::{
    PartitionInfoTrait, PartitionTable, PartitionTableReadExt,
};

# fn main() -> hadris_part::Result<()> {
let mut disk = File::open("disk.img")?;
let scheme = PartitionTable::read_from(&mut disk, 512)?;

for part in scheme.partitions() {
    println!(
        "Partition {}: {} sectors at LBA {}",
        part.index,
        part.size_sectors,
        part.start_lba
    );
}
# Ok(())
# }

Reading an MBR directly

use std::fs::File;
use hadris_part::{MasterBootRecord, MasterBootRecordReadExt, PartitionInfoTrait};

# fn main() -> hadris_part::Result<()> {
let mut disk = File::open("disk.img")?;
let mbr = MasterBootRecord::read_from(&mut disk)?;

for partition in mbr.get_partition_table().iter() {
    if partition.sector_count.to_ne() == 0 {
        continue;
    }
    println!(
        "Partition: {} sectors at LBA {}",
        partition.size_sectors(),
        partition.start_lba()
    );
}
# Ok(())
# }

Reading a GPT disk

use std::fs::File;
use hadris_part::{GptDisk, GptDiskReadExt};

# fn main() -> hadris_part::Result<()> {
let mut disk = File::open("disk.img")?;
let gpt = GptDisk::read_from(&mut disk, 512)?;

for (idx, entry) in gpt.partitions() {
    if entry.is_unused() {
        continue;
    }
    println!(
        "Partition {}: type {:?} first_lba={}",
        idx,
        entry.type_guid,
        entry.first_lba.to_ne()
    );
}
# Ok(())
# }

For Bootloaders (minimal footprint)

[dependencies]
hadris-part = { version = "2.1.0", default-features = false, features = ["read", "sync"] }

For Desktop Applications

[dependencies]
hadris-part = { version = "2.1.0", features = ["write"] }  # read is already default
# Optional GPT CRC verification:
# hadris-part = { version = "2.1.0", features = ["write", "crc"] }

Partition Types

MBR Partition Types

Common partition type IDs:

• 0x00 - Empty
• 0x0B - FAT32 (CHS)
• 0x0C - FAT32 (LBA)
• 0x0E - FAT16 (LBA)
• 0x07 - NTFS/exFAT
• 0x83 - Linux
• 0xEE - GPT Protective MBR

GPT Partition GUIDs

Common partition type GUIDs:

• EFI System Partition: C12A7328-F81F-11D2-BA4B-00A0C93EC93B
• Microsoft Basic Data: EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
• Linux Filesystem: 0FC63DAF-8483-4772-8E79-3D69D8477DE4

Constants are available on Guid (e.g. Guid::EFI_SYSTEM).

Documentation

• Inspect a partition table
• Open FAT inside a partition
• API reference

License

Licensed under the MIT license.