The Pigweed C/C++ API is grouped by Pigweed modules. If you're looking for something specific, but can't remember what Pigweed module it belongs to, try searching for it by name.

[detail level 12345]

▼Async & concurrency	Cooperative multitasking, futures, and asynchronous primitives
►pw_async	Portable APIs for asynchronous code
pw_async_basic
►pw_async2	Cooperative async tasks for embedded
Channels	Inter-task communication
Combinators	Helpers for interacting with multiples futures
Configuration	Compile-time configuration
Context	Resources for scheduling asynchronous work
Coroutines	C++20 coroutine support
Deprecated	Deprecated APIs
Dispatchers	Interface for the cooperative scheduler and concrete implementations
Dynamic allocation	Heap allocate space for tasks
Futures	Values that may not be ready yet
Poll	Statuses for asynchronous operations
Tasks	Logical collections of asynchronous work
Time	Interacting with time, timers, and timeouts
Wakers	Queue work in response to async events
pw_work_queue
▼Build systems	Bazel, GN, and CMake integrations and rules
pw_build	Integrations for Bazel, GN, and CMake
▼Comms	Remote procedure calls (RPC), channels, and communication streams
►Bluetooth	Dual-mode Bluetooth Host stack, HCI controllers, and profiles
pw_bluetooth	Host-layer Bluetooth Low Energy APIs and utilities
pw_bluetooth_proxy	Lightweight proxy for augmenting Bluetooth functionality
pw_bluetooth_sapphire	Battle-tested Bluetooth with rock-solid reliability
►pw_channel	Async, zero-copy API for sending and receiving bytes or datagrams
Forwarding
Loopback
RP2 stdio
Stream channel
pw_cobs	Consistent Overhead Byte Stuffing (COBS) codec and zero-copy frame streamer
pw_hdlc	Simple, robust, and efficient serial communication
►pw_rpc	Efficient, low-code-size RPC system for embedded devices
Benchmarking & testing
Channels
Configuration	User-provided header to optionally override options in this file
Synchronous API
►pw_rpc2	Next gen, zero-copy async RPC with end-to-end backpressure
Client	Connect to an RPC server and invoke RPC methods
Readers and writers	Read and write RPC messages and responses
Server	Register RPC services and accept incoming client connections
Status	Status codes and result types for RPC operations
Testing	Unit test RPC services and clients end to end
►pw_stream	A foundational interface for streaming data
Implementations	Concrete implementations of stream interfaces for general use
►Interfaces	Generic stream interfaces that support a combination of reading, writing, and seeking
ReaderWriters	Streams that support both reading and writing
Readers	Streams that support reading but not writing
Writers	Streams that support writing but not reading
pw_stream_uart_linux	UART stream implementation for Linux
pw_transfer
pw_transport	Asynchronous datagram-oriented transport interface
▼Cryptography & security	Hashing, cryptographic primitives, and secure storage
pw_crypto
pw_random
▼Data structures & utilities	Embedded-safe collections, spans, strings, status, and error handling
►pw_containers	Generic collections of objects for embedded devices
C API
Lists
Maps
►Queues
C++ API
Sets
Utilities
Vectors
pw_enum	Rich enum support
pw_function	Embedded-friendly std::function
pw_numeric	Efficient mathematical utilities for embedded
pw_result	Error propagation primitives: value-or-error
►pw_span	Std::span for C++17
Cast
pw_status	Exception-free error propagation for embedded
►pw_string	Efficient, easy, and safe string manipulation
InlineString and InlineBasicString	Safer alternatives to `std::string` and `std::basic_string`
StringBuilder	The flexibility of `std::ostringstream` but with a small footprint
UTF-8 helpers	Basic helpers for reading and writing UTF-8-encoded strings
Utilities	Safer alternatives to C++ standard library string functions
▼Encoding & serialization	Protocol Buffers, JSON, Varint, Base64, and wire format serialization
pw_base64	Base64 encoding, decoding, and validating
►pw_bytes	Utilities for manipulating binary data
Alignment	Functions for memory alignment
Bit manipulation	C++20 `<bit>` features and extensions
Byte arrays	Compile-time construction of byte arrays
Byte builders	Dynamically build byte sequences in fixed-size buffers
Byte spans	Aliases for `pw::span` of bytes
Byte suffixes	Convenient literal for `std::byte`
Byte units	Constants and literals for byte sizes e.g. KiB
Endian conversion	Utilities for handling byte order
Packed pointers	Store data in unused pointer bits
►pw_json	Simple, efficient C++ JSON serialization
Builder API	Serialize JSON into fixed-size buffers
►pw_protobuf	Expressive interface for encoding and decoding protocol buffers
Find APIs
pw_uuid	128-bit universally unique identifier (UUID)
pw_varint	Functions for encoding and decoding variable length integers
▼HALs	Hardware abstraction layer interfaces for timers, I2C, SPI, UART, and GPIO
pw_analog	Analog-to-digital converter libraries and utilities
►pw_clock_tree	Clock tree management for embedded devices
pw_clock_tree_mcuxpresso	NXP MCUXpresso SDK implementation for pw_clock_tree
►pw_digital_io	Digital I/O interface
pw_digital_io_mcuxpresso	Digital I/O for NXP MCUXpresso
►pw_display	Graphic display support and framebuffer management
Color
►pw_i2c	Cross-platform I2C API with interactive debugging
pw_i2c_linux	Linux userspace implementation for pw_i2c
pw_i2c_zephyr	Zephyr implementation for pw_i2c
pw_spi
pw_sys_io
pw_uart	Core interfaces for UART communication
▼Hardware support	Board support, hardware drivers, and SDK integrations for target platforms
►NXP	Drivers, build utilities, & HAL implementations for NXP MCUXpresso SDK
pw_clock_tree_mcuxpresso	NXP MCUXpresso SDK implementation for pw_clock_tree
pw_digital_io_mcuxpresso	Digital I/O for NXP MCUXpresso
▼Memory & storage	Memory allocators, buffers, persistent flash storage, and key-value stores
pw_alignment	Natural object alignment, guaranteed
►pw_allocator	Flexible, safe, and measurable memory allocation
►Blocks	An allocatable region of memory
Block implementations	The following combine block mix-ins and provide both the methods they require as well as a concrete representation of the data those methods need
Block mix-ins	Blocks are defined using several stateless “mix-in” interface types
Buckets	Data structures that track free blocks
►Concrete allocators	Concrete allocator implementations that provide memory dynamically
Block allocators
Configuration	Options for controlling block poisoning intervals, validation checks, and deprecation warnings
Core interfaces	Generic allocator interfaces that can be injected into routines that need dynamic memory
Forwarding allocators	Allocator implementations that don’t allocate memory directly and instead rely on other allocators while providing additional behaviors
►Implementation interfaces	Interfaces for allocator implementers
Size reports	Generate code size reports for allocator implementations
►Testing and debugging	Test utilities for allocator implementers
FuzzTest support
Utilities	Helpers for metrics, fragmentation, and buffer management
pw_buf	Contiguous buffer views with optional memory ownership
pw_kvs	Lightweight, persistent key-value store
pw_malloc	Replacement interface for standard libc dynamic memory operations
►pw_multibuf	A buffer API optimized for zero-copy messaging
Experimental v2 API	Experimental API that separates out the concern of memory allocation
►Legacy v1 API	Interfaces that will eventually be deprecated
Allocator implementation API
Test-only features
▼OS abstraction layers	Synchronization, threading, and portable RTOS abstractions
►Backends	Operating system, RTOS, and bare-metal backends for Pigweed's OS abstraction layers
►Android	Utilities and toolchains for using Pigweed on Android
pw_chre	Android Context Hub Runtime Environment backend
►Zephyr	Modules, backends, and helpers for the Zephyr RTOS
pw_i2c_zephyr	Zephyr implementation for pw_i2c
pw_chrono	Portable std::chrono for constrained embedded devices
pw_interrupt	Interrupt handling utilities for embedded systems
pw_sync	Portable abstraction for synchronization primitives
pw_system
pw_thread	Thread creation and execution
▼Observability	Structured logging, tokenization, metrics, crash handling, and tracing
pw_assert	Flexible crash triggering and handling
pw_hex_dump	Handy hexdump utilities
►pw_log	Robust and portable logging for embedded projects
Global config
Google Logging (glog) macros
Module config
Protobuf helpers
Short macros	Optional shortened versions of the `PW_LOG` macros
Tokenized args
pw_log_string
pw_log_tokenized
pw_metric
pw_persistent_ram	Reliable memory across reboots for crash reporting
►pw_tokenizer	Compress strings to shrink logs by +75%
Configuration	Tokenization customization options
Detokenization	Expand a token to the string it represents and decode its arguments
Token databases	Store a mapping of tokens to the strings they represent
Tokenization	Convert string literals to tokens
►pw_trace
pw_trace_tokenized
Pw_multibuf_v1_adapter
Pw_trace_tokenzed
▼Testing	Unit testing frameworks, mocking, compilation tests, and fuzzing
pw_perf_test	Micro-benchmarks that are easy to write and run
►pw_unit_test	GoogleTest for embedded
Assertions
Configuration
Constexpr tests
Event handlers
Expectations
Helpers
Test control
Test declaration
▼Toolchains	Hermetic LLVM/Clang toolchains, C/C++ libraries, and build utilities
pw_bloat	Utilities for generating binary size reports
pw_elf	ELF file support
pw_polyfill
►pw_preprocessor	Helpful preprocessor macros
►Internal	Internal implementation details
Compiler	Public compiler attributes and macros
pw_toolchain	Embedded toolchains for GN-based Pigweed projects
▼third-party	API integrations with third-party software e.g. FreeRTOS
FreeRTOS	FreeRTOS application functions