Implementation Details

Internal implementation details for the Magic class. More...

Collaboration diagram for Implementation Details:

Topics
	Constructors
	MagicPrivate construction methods.
	Special Member Functions
	Move, copy, and destruction operations.
	Validity Checking
	Database validation methods.
	Instance Control
	Instance lifecycle management.
	Flag Management
	Flag retrieval methods.
	Parameter Management
	Parameter retrieval methods.
	File Identification
	Core file type detection methods.
	State Queries
	Instance state inspection methods.
	Database Loading
	Magic database loading methods.
	Open Reopen
	Instance initialization methods.
	Flag Modification
	Flag modification methods.
	Parameter Modification
	Parameter modification methods.
	Error Handling
	Centralized exception throwing utilities.
	Member Variables
	Core state variables for lifecycle management.
	Validation Option Masks
	Pre-computed option masks for file identification.
	Libmagic Constants
	Constants for libmagic integration.
	Libmagic Type Aliases
	Type definitions for libmagic interoperability.
	Friend Declarations For ToString Access To Private Constants
	Friend declarations for string conversion access.

Namespaces
namespace	Recognition::Detail
	Internal namespace for libmagic C library integration.

Classes
class	Recognition::Magic::MagicPrivate
	PIMPL implementation class for Magic. More...
struct	Recognition::Magic::MagicPrivate::FlagsConverter
	Converter between C++ flag types and libmagic flag values. More...
struct	Recognition::Magic::MagicPrivate::LibmagicPairConverter
	Extracts values from libmagic constant pairs. More...

Detailed Description

Internal implementation details for the Magic class.

This group contains implementation-specific types, constants, and helper classes used by the Magic class PIMPL implementation.

Quick Start (Internal Usage)

// MagicPrivate is accessed only through the Magic public interface
Magic magic{Magic::Flags::Mime};
 
// Internally, Magic delegates to MagicPrivate:
// magic.IdentifyFile(path) -> m_impl->IdentifyFile(path)
auto type = magic.IdentifyFile("/path/to/file");

Error Handling

Internal methods use a template-based approach for consistent error handling:

• ThrowExceptionOnFailure: Validates preconditions and throws on failure
• GetErrorMessage(): Retrieves libmagic error strings

// Throwing version pattern
void MagicPrivate::SomeMethod() {
    ThrowExceptionOnFailure<MagicIsClosed>(IsOpen());
    auto result = Detail::magic_operation(m_cookie.get());
    ThrowExceptionOnFailure<MagicOperationError>(result, GetErrorMessage());
}
 
// Noexcept version pattern
std::expected<T, E> MagicPrivate::SomeMethod(std::nothrow_t) noexcept {
    if (!IsOpen()) {
        return std::unexpected{"Magic is closed"};
    }
    // ... operation ...
}