Utilities

Generic helpers shared by the firmware, the bootloader and host tools (lib/util). More...

Modules
	Library assertions
	Assertions of the utility library.
	Base64
	Base64 encoding.
	Bit operations
	Bit sets stored in byte or word arrays, rotation and bit reversal.
	Bits and bit fields
	Bit, mask and register field macros.
	Linear buffer
	Append-only byte buffer with its storage after the header.
	Build ID
	GNU build ID note inserted by the linker.
	Byte order
	Conversions between the CPU byte order (always little-endian) and fixed byte orders.
	Circular buffer
	Single-reader, single-writer byte ring buffer.
	Circular cache
	Fixed-size, array-backed cache that evicts its oldest item.
	Generic attributes
	Packed lists of id/length/value attributes, as exchanged with the phone.
	Hashing
	Non-cryptographic hash.
	Heap
	First-fit heap allocator over a caller-provided memory region.
	Hex dump
	xxd-style hex dumps through a line callback.
	Iterator
	Generic bidirectional iterator over caller-defined state.
	Keyed circular cache
	Fixed-size cache of items looked up by integer key, evicting the oldest item.
	Linked list
	Intrusive doubly linked list.
	Listify
	Preprocessor repetition.
	Library logging
	Logging hooks of the utility library.
	Integer math
	Integer math macros and helpers.
	Fixed-point math
	Signed fixed-point types and a generic recursive filter.
	Miscellaneous
	Small generic macros.
	Ordering
	Comparator type used by the sorted containers.
	Pascal strings
	Length-prefixed strings and lists of them.
	Random numbers
	Random number source used by the library.
	Ratios
	Real numbers in [0, 1] stored as scaled integers.
	Shared circular buffer
	Circular buffer with one writer and several independent readers.
	Sizes
	Array and member size helpers.
	Singly linked list
	Intrusive singly linked list.
	Sorting
	In-place sorting of small arrays.
	Statistics
	Basic statistics over arrays of int32_t.
	Strings
	String helpers.
	String lists
	Serialized arrays of NUL-separated strings.
	Structure access
	Structure access helpers.
	Unit test hooks
	Linkage helpers that let unit tests override firmware functions.
	Calendar time
	Calendar arithmetic independent of the time zone and the RTC.
	Trigonometry
	Fixed-point trigonometry helpers.
	Units
	Size, distance and time unit conversion factors.
	UTF-8
	UTF-8 decoder (Bjoern Hoehrmann's DFA).
	UUID
	128-bit universally unique identifiers.

Detailed Description

Generic helpers shared by the firmware, the bootloader and host tools (lib/util).

The library does not depend on the kernel. Logging and assertions go through util_log() and util_assertion_failed(), weak functions the firmware overrides.

static const uint16_t s_rates[] = {10, 25, 50, 100};
 
for (size_t i = 0; i < ARRAY_LENGTH(s_rates); i++) {
  max_rate = MAX(max_rate, s_rates[i]);
}
level = CLIP(level, 0, 100);
 
struct item *item = container_of(node, struct item, list_node);