YAPB - Yet Another Protocol Buffer format. More...

#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include <stdalign.h>

Data Structures
struct	YAPB_Packet
	Opaque packet handle, stack-allocatable. More...
struct	YAPB_Element
	Tagged union returned by YAPB_pop_next(). More...

Macros
#define	YAPB_MODE_WRITE 0
	Packet is in write mode.
#define	YAPB_MODE_READ 1
	Packet is in read mode.
#define	YAPB_HEADER_SIZE 4
	Size of the packet header in bytes.
#define	YAPB_PACKET_SIZE 48
	Size of the opaque YAPB_Packet_t storage in bytes.

Typedefs
typedef struct YAPB_Packet	YAPB_Packet_t
	Opaque packet handle, stack-allocatable.
typedef struct YAPB_Element	YAPB_Element_t
	Tagged union returned by YAPB_pop_next().

Enumerations
enum	YAPB_Type_t { YAPB_INT8 = 0x00 , YAPB_INT16 = 0x01 , YAPB_INT32 = 0x02 , YAPB_INT64 = 0x03 , YAPB_FLOAT = 0x04 , YAPB_DOUBLE = 0x05 , YAPB_BLOB = 0x0E , YAPB_NESTED_PKT = 0x0F }
	Element type tags stored in the wire format. More...
enum	YAPB_Result_t { YAPB_ERR_NO_MORE_ELEMENTS = -7 , YAPB_ERR_INVALID_PACKET = -6 , YAPB_ERR_TYPE_MISMATCH = -5 , YAPB_ERR_INVALID_MODE = -4 , YAPB_ERR_BUFFER_TOO_SMALL = -3 , YAPB_ERR_NULL_PTR = -2 , YAPB_ERR_UNKNOWN = -1 , YAPB_OK = 0 , YAPB_STS_COMPLETE = 1 }
	Result codes returned by all YAPB functions. More...

Functions
YAPB_Result_t	YAPB_initialize (YAPB_Packet_t pkt, uint8_t buffer, size_t size)
	Initialize a packet for writing.
YAPB_Result_t	YAPB_finalize (YAPB_Packet_t pkt, size_t out_len)
	Finalize the packet, writing the total length into the header.
YAPB_Result_t	YAPB_load (YAPB_Packet_t pkt, const uint8_t data, size_t size)
	Load a packet for reading from raw data.
YAPB_Result_t	YAPB_push_i8 (YAPB_Packet_t pkt, const int8_t val)
	Push a signed 8-bit integer.
YAPB_Result_t	YAPB_push_i16 (YAPB_Packet_t pkt, const int16_t val)
	Push a signed 16-bit integer.
YAPB_Result_t	YAPB_push_i32 (YAPB_Packet_t pkt, const int32_t val)
	Push a signed 32-bit integer.
YAPB_Result_t	YAPB_push_i64 (YAPB_Packet_t pkt, const int64_t val)
	Push a signed 64-bit integer.
YAPB_Result_t	YAPB_push_float (YAPB_Packet_t pkt, const float val)
	Push a single-precision float.
YAPB_Result_t	YAPB_push_double (YAPB_Packet_t pkt, const double val)
	Push a double-precision float.
YAPB_Result_t	YAPB_push_blob (YAPB_Packet_t pkt, const uint8_t data, uint16_t len)
	Push a raw byte blob.
YAPB_Result_t	YAPB_push_nested (YAPB_Packet_t pkt, const YAPB_Packet_t nested)
	Push a finalized nested packet.
YAPB_Result_t	YAPB_pop_next (YAPB_Packet_t pkt, YAPB_Element_t out)
	Pop the next element regardless of its type.
YAPB_Result_t	YAPB_pop_i8 (YAPB_Packet_t pkt, int8_t out)
	Pop a signed 8-bit integer.
YAPB_Result_t	YAPB_pop_i16 (YAPB_Packet_t pkt, int16_t out)
	Pop a signed 16-bit integer.
YAPB_Result_t	YAPB_pop_i32 (YAPB_Packet_t pkt, int32_t out)
	Pop a signed 32-bit integer.
YAPB_Result_t	YAPB_pop_i64 (YAPB_Packet_t pkt, int64_t out)
	Pop a signed 64-bit integer.
YAPB_Result_t	YAPB_pop_float (YAPB_Packet_t pkt, float out)
	Pop a single-precision float.
YAPB_Result_t	YAPB_pop_double (YAPB_Packet_t pkt, double out)
	Pop a double-precision float.
YAPB_Result_t	YAPB_pop_blob (YAPB_Packet_t pkt, const uint8_t data, uint16_t len)
	Pop a raw byte blob.
YAPB_Result_t	YAPB_pop_nested (YAPB_Packet_t pkt, YAPB_Packet_t out)
	Pop a nested packet.
YAPB_Result_t	YAPB_get_error (const YAPB_Packet_t *pkt)
	Get the sticky error state of a packet.
YAPB_Result_t	YAPB_get_elem_count (const YAPB_Packet_t pkt, uint16_t out_count)
	Count the number of elements in a packet.
const char *	YAPB_Result_str (YAPB_Result_t result)
	Get a human-readable string for a result code.
const uint8_t *	YAPB_get_buffer (const YAPB_Packet_t pkt, size_t out_len)
	Get a const pointer to the packet's backing buffer and its length.
bool	YAPB_check_complete (const uint8_t *data, size_t len)
	Check if a receive buffer contains a complete YAPB packet.

Detailed Description

YAPB - Yet Another Protocol Buffer format.

Packet structure:

Header: 4 bytes pkt_len (network byte order, total packet size)
Data: Each element = 1 byte type + value (network byte order)
For BLOB: type + 2 byte length + raw bytes
For NESTED_PKT: type + nested packet (with its own 4 byte header)

Error handling: YAPB uses sticky errors (like errno/OpenGL). Once an error occurs, all subsequent pop/push calls return immediately with that error. Check the final state with YAPB_get_error() after a sequence of operations.

Pop functions do NOT modify the output value on error. This enables forward compatibility - initialize fields to defaults before popping, and they'll keep their default if the packet lacks that field:

uint16_t new_field = 42; // default for older packets

YAPB_pop_u16(pkt, &new_field); // stays 42 if packet ended

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description