Struct FileBuffer 

pub struct FileBuffer { /* private fields */ }

A memory-mapped file buffer for efficient file access

This struct provides safe access to file contents through memory mapping, which avoids loading the entire file into memory while providing fast random access to file data.

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;
let data = buffer.as_slice();
println!("File size: {} bytes", data.len());

Implementations

impl FileBuffer

pub fn new(path: &Path) -> Result<Self, IoError>

Creates a new memory-mapped file buffer

Arguments

• path - Path to the file to be mapped

Returns

Returns a FileBuffer on success, or an IoError if the file cannot be opened or mapped.

Errors

This function will return an error if:

• The file does not exist or cannot be opened
• The file cannot be memory-mapped
• The file is empty
• The file is larger than the maximum allowed size
• File metadata cannot be read

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;

pub fn create_symlink<P: AsRef<Path>, Q: AsRef<Path>>( original: P, link: Q, ) -> Result<(), Error>

Creates a symlink in a cross-platform manner

Arguments

• original - The path to the original file or directory
• link - The path where the symlink should be created

Errors

• Returns std::io::Error if symlink creation fails (e.g., insufficient permissions)
• On Windows, may require admin privileges or developer mode enabled
• On non-Unix/Windows platforms, returns an “Unsupported” error

pub fn as_slice(&self) -> &[u8]

Returns the file contents as a byte slice

This provides safe access to the memory-mapped file data without copying the contents.

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;
let data = buffer.as_slice();
println!("First byte: 0x{:02x}", data[0]);

pub fn path(&self) -> &Path

Returns the path of the file

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;
println!("File path: {}", buffer.path().display());

pub fn len(&self) -> usize

Returns the size of the file in bytes

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;
println!("File size: {} bytes", buffer.len());

pub fn is_empty(&self) -> bool

Returns true if the file is empty

Note: This should never return true for a successfully created FileBuffer, as empty files are rejected during construction.

Examples

use libmagic_rs::io::FileBuffer;
use std::path::Path;

let buffer = FileBuffer::new(Path::new("example.bin"))?;
assert!(!buffer.is_empty()); // Should always be false for valid buffers

Trait Implementations

impl Debug for FileBuffer

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for FileBuffer

fn drop(&mut self)

Executes the destructor for this type.