Function load_magic_directory 

pub fn load_magic_directory(
    dir_path: &Path,
) -> Result<Vec<MagicRule>, ParseError>

Loads and parses all magic files from a directory, merging them into a single rule set.

This function reads all regular files in the specified directory, parses each as a magic file, and combines the resulting rules into a single Vec<MagicRule>. Files are processed in alphabetical order by filename to ensure deterministic results.

Error Handling Strategy

This function distinguishes between critical and non-critical errors:

• Critical errors (I/O failures, directory access issues, encoding problems): These cause immediate failure and return a ParseError. The function stops processing and propagates the error to the caller.

• Non-critical errors (individual file parse failures): These are logged to stderr with a warning message and the file is skipped. Processing continues with remaining files.

Behavior

• Subdirectories are skipped (not recursively processed)
• Symbolic links are skipped
• Empty directories return an empty rules vector
• Files are processed in alphabetical order by filename
• All successfully parsed rules are merged in order

Examples

Loading a directory of magic files:

use libmagic_rs::parser::load_magic_directory;
use std::path::Path;

let rules = load_magic_directory(Path::new("/usr/share/file/magic.d"))?;
println!("Loaded {} rules from directory", rules.len());

Creating a Magdir-style directory structure:

use libmagic_rs::parser::load_magic_directory;
use std::path::Path;

// Directory structure:
// magic.d/
//   ├── 01-elf
//   ├── 02-archive
//   └── 03-text

let rules = load_magic_directory(Path::new("./magic.d"))?;
// Rules from all three files are merged in alphabetical order

Errors

Returns ParseError if:

• The directory does not exist or cannot be accessed
• Directory entries cannot be read
• A file cannot be read due to I/O errors
• A file contains invalid UTF-8 encoding

Panics

This function does not panic under normal operation.