Module utils 

Utility functions and types to help with creating custom VFS implementations. Low-level utilities, traits, and macros for implementing custom SQLite Virtual File Systems (VFS).

Modules

x_methods_shim

A module containing shims for VFS methods that are implemented using JavaScript interoperability.

Macros

bail

A macro to return a specific SQLite error code if a condition is true.

check_option

A macro to safely unwrap an Option<T>, returning a SQLite error code on None.

check_result

A macro to safely unwrap a Result<T, E>, returning a SQLite error code on Err.

unused

A macro to explicitly mark a parameter as unused, suppressing compiler warnings.

Structs

LazyCell

A wrapper around once_cell::unsync::Lazy that provides Send and Sync trait implementations when the atomics target feature is not enabled, allowing for thread-local static initialization.

MemChunksFile

An in-memory file implementation that stores data in fixed-size chunks. Suitable for temporary files.

SQLiteVfsFile

The core file-handle structure for a custom VFS, designed to be compatible with SQLite’s C interface.

VfsAppData

A wrapper for the pAppData pointer in sqlite3_vfs, providing a safe way to manage VFS-specific application data and error states.

VfsError

A container for VFS-specific errors, holding both an error code and a descriptive message.

Enums

ImportDbError

RegisterVfsError

Represents errors that can occur during the VFS registration process.

Constants

SQLITE3_HEADER

The header of the SQLite file is used to determine whether the imported file is legal.

Traits

SQLiteIoMethods

A trait that abstracts the sqlite3_io_methods struct, allowing for a more idiomatic Rust implementation.

SQLiteVfs

A trait that abstracts the sqlite3_vfs struct, allowing for a more idiomatic Rust implementation.

VfsFile

A trait defining the basic I/O capabilities required for a VFS file implementation.

VfsStore

Make changes to files

Functions

check_db_and_page_size

Check db and page size, page size must be a power of two between 512 and 65536 inclusive, db size must be a multiple of page size.

check_import_db

Simple verification when importing db, and return page size;

random_name

Generates a random, temporary filename, typically used when SQLite requests a file with a NULL name.

register_vfs

A generic function to register a custom VFS implementation with SQLite.

registered_vfs

Checks if a VFS with the given name is already registered with SQLite and returns a pointer to it if found.

Type Aliases

VfsResult

A specialized Result type for VFS operations.