esp-wifi-sys

The esp-wifi-sys repository provides low-level bindings and binaries for wireless drivers.

Note: If you are looking for the high-level Rust wireless driver implementation, you should use esp-wifi located in the esp-hal repository instead.

Depending on the lld version used by your toolchain, you may encounter linker errors regarding relocation to a symbol in a discarded section (e.g., .L0) when using the provided libraries.

To resolve this, you must strip the .eh_frame segment from the affected binaries using objcopy. Replace the path below with the actual path to your library file.

riscv32-esp-elf-objcopy --remove-section=.eh_frame <path_to_library>.a

The esp-wifi-sys crate provides a mechanism for the underlying C wireless drivers to output logs to the Rust environment. This is controlled by the sys-logs feature flag.

• When sys-logs is enabled: The crate implements __esp_radio_printf, which captures C-level log calls and routes them through the Rust info! macro. This allows you to see wireless driver logs in your Rust application's logging output.
• When sys-logs is disabled: __esp_radio_printf is implemented as a no-op, preventing any overhead from logging calls made by the driver.

# Example Cargo.toml configuration to enable radio logging
[dependencies]
esp-wifi-sys-esp32c61 = {
    version = "0.8.1",
    features = ["sys-logs"]
}

The esp-wifi-sys-esp32c3 crate provides a hook for radio-level logging via the __esp_radio_printf function.

• If the sys-logs feature is enabled, __esp_radio_printf is implemented to route logs through the system's info! macro, allowing you to see radio driver messages in your application logs.
• If the sys-logs feature is disabled, __esp_radio_printf is a no-op stub.

The esp-wifi-sys-esp32s3 crate provides a hook for wireless driver logging through the __esp_radio_printf function.

• If the sys-logs feature is enabled, __esp_radio_printf is implemented to route driver logs to the system's info! macro.
• If the sys-logs feature is disabled, __esp_radio_printf is a no-op, effectively silencing driver logs.

This allows developers to control whether low-level wireless driver messages are visible in their application logs by toggling the feature flag in their Cargo.toml.

# To enable driver logging
[dependencies]
esp-wifi-sys-esp32s3 = { version = "0.8.1", features = ["sys-logs"] }

The esp-wifi-sys-esp32c2 crate provides low-level FFI bindings for the ESP32C2 wireless drivers. The primary interface for accessing the underlying C functions and types is through the include module. This module contains the bindgen-generated bindings that map directly to the ESP-IDF/ESP-Wi-Fi C headers.

// Accessing the generated bindings
use esp_wifi_sys_esp32c2::include::*;

The __esp_radio_printf function is an exported C-compatible function used to bridge radio-level logging from the underlying C drivers to the Rust environment.

• If the sys-logs feature is enabled, this function routes logs to the info! macro.
• If the sys-logs feature is disabled, the function is a no-op.

This function is typically called by the underlying C wireless drivers to output tagged messages.

// Note: This is an extern "C" function intended to be called by the C driver.
// It is not typically called directly by the Rust user, but its behavior 
// depends on the 'sys-logs' feature.
extern "C" {
    fn __esp_radio_printf(tag: *const core::ffi::c_char, msg: *const core::ffi::c_char);
}