rt-thread/components/rust/docs/4.modules/modules.md

Writing a Rust Dynamic Library Usable by RT-Thread

1. Set up the project Create a new cargo project as usual. There are some flags to tell cargo to generate a system library instead of a regular Rust target.

   [lib]
   name = "your_crate"
   crate-type = ["cdylib"]      # generate a dynamic library
   # crate-type = ["staticlib"] # generate a static library
   

Add the following to config.toml to specify the target platform:

[build]
target = "your_target"

1. Enable RT-Thread dynamic module loading To load dynamic modules in RT-Thread, enable it in Kconfig:

   RT-Thread Components → C/C++ and POSIX layer 
   → POSIX (Portable Operating System Interface) layer 
       → Enable dynamic module APIs, dlopen()/dlsym()/dlclose() etc
   

2. Enable the filesystem To place dynamic modules into RT-Thread, enable a filesystem in Kconfig:

   RT-Thread online packages → system packages 
   → lwext4: an excellent choice of ext2/3/4 filesystem for microcontrollers.
   

Using the rust library

Add rt_rust dependency in Cargo.toml:

[dependencies]
rt_rust = { path = "PATH/TO/rust/rt-rust" }

Currently the macro-main library is not supported because it causes entry detection issues.

References

• The Embedded Rust Book