qc-cli 0.5.1

qc is designed to give you an instant breakdown of your codebase composition. It uses Memory Mapping (Mmap) and Parallel Directory Walking to scan tens of thousands of files in milliseconds.
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// src/walk/io.rs

use memmap2::Mmap;
use std::{fs::File, path::Path};

/// Opens a file and memory-maps it as read-only.
///
/// Returns `None` if:
/// - the file cannot be opened
/// - the file cannot be memory-mapped
///
/// # Safety
/// All unsafe code is contained within this function.
/// The mapping is read-only and valid for the lifetime of the returned `Mmap`.
pub fn map_file(path: &Path) -> Option<Mmap> {
    let file = File::open(path).ok()?;

    // SAFETY:
    // - The file descriptor outlives the Mmap
    // - The mapping is read-only
    // - We do not mutate through the mapping
    unsafe { Mmap::map(&file).ok() }
}