ckb-std

This library contains several modules that help you write CKB contract with Rust.

Usage

Documentation

Modules

• syscalls module: defines CKB syscalls
• high_level module: defines high level APIs
• dynamic_loading module: dynamic loading primitives
• debug! macro: a println! like macro helps debugging
• entry! macro: defines contract entry point
• default_alloc! macro: defines global allocator for no-std rust
• dummy_atomic module: dummy atomic operations
• logger module: colored logger implementation
• type_id module: Type ID implementation (feature type-id)

Memory allocator

Default allocator uses a mixed allocation strategy:

• Fixed block heap, only allocate fixed size(64B) memory block
• Dynamic memory heap, allocate any size memory block

User can invoke macro with arguments to customize the heap size. The default heap size arguments are:

(fixed heap size 4KB, dynamic heap size 516KB, dynamic heap min memory block 64B)

Use the macro with arguments to change it:

default_alloc!(4 * 1024, 516 * 1024, 64)

Beware, use difference heap size or memory block size may affect the verification result of the contract, some runtime errors such as out of memory may occur; you should always test the contract after customizing.

Examples

Check examples and tests to learn how to use.

See also ckb-tool which helps you write tests.

Upgrading Issues

Starting from ckb-std 0.16.0, RISC-V atomic instructions are generated by default. However, ckb-vm doesn't directly support atomic instructions. To address this, ckb-std provides the following solutions:

1. Use the "dummy-atomic" feature (enabled by default)
2. Adjust Rust compilation flags by adding -C target-feature=-a to RUSTFLAGS

For more detailed information on compilation flags, refer to the CKB Script Templates repository.