types.hpp File Reference

Go to the source code of this file.

#include "errors.hpp"
#include "visibility.hpp"
#include <cstddef>
#include <cstdint>
#include <functional>
#include <limits>
#include <memory>
#include <optional>
#include <string>
#include <unordered_map>
#include <vector>

Classes
struct	mcap::Record
	A generic Type-Length-Value record using a uint8 type and uint64 length. This is the generic form of all MCAP records. More...
struct	mcap::Header
	Appears at the beginning of every MCAP file (after the magic byte sequence) and contains the recording profile (see https://github.com/foxglove/mcap/tree/main/docs/specification/profiles) and a string signature of the recording library. More...
struct	mcap::Footer
	The final record in an MCAP file (before the trailing magic byte sequence). Contains byte offsets from the start of the file to the Summary and Summary Offset sections, along with an optional CRC of the combined Summary and Summary Offset sections. A summaryStart and summaryOffsetStart of zero indicates no Summary section is available. More...
struct	mcap::Schema
	Describes a schema used for message encoding and decoding and/or describing the shape of messages. One or more Channel records map to a single Schema. More...
struct	mcap::Channel
	Describes a Channel that messages are written to. A Channel represents a single connection from a publisher to a topic, so each topic will have one Channel per publisher. Channels optionally reference a Schema, for message encodings that are not self-describing (e.g. JSON) or when schema information is available (e.g. JSONSchema). More...
struct	mcap::Message
	A single Message published to a Channel. More...
struct	mcap::Chunk
	An collection of Schemas, Channels, and Messages that supports compression and indexing. More...
struct	mcap::MessageIndex
	A list of timestamps to byte offsets for a single Channel. This record appears after each Chunk, one per Channel that appeared in that Chunk. More...
struct	mcap::ChunkIndex
	Chunk Index records are found in the Summary section, providing summary information for a single Chunk and pointing to each Message Index record associated with that Chunk. More...
struct	mcap::Attachment
	An Attachment is an arbitrary file embedded in an MCAP file, including a name, media type, timestamps, and optional CRC. Attachment records are written in the Data section, outside of Chunks. More...
struct	mcap::AttachmentIndex
	Attachment Index records are found in the Summary section, providing summary information for a single Attachment. More...
struct	mcap::Statistics
	The Statistics record is found in the Summary section, providing counts and timestamp ranges for the entire file. More...
struct	mcap::Metadata
	Holds a named map of key/value strings containing arbitrary user data. Metadata records are found in the Data section, outside of Chunks. More...
struct	mcap::MetadataIndex
	Metadata Index records are found in the Summary section, providing summary information for a single Metadata record. More...
struct	mcap::SummaryOffset
	Summary Offset records are found in the Summary Offset section. Records in the Summary section are grouped together, and for each record type found in the Summary section, a Summary Offset references the file offset and length where that type of Summary record can be found. More...
struct	mcap::DataEnd
	The final record in the Data section, signaling the end of Data and beginning of Summary. Optionally contains a CRC of the entire Data section. More...
struct	mcap::RecordOffset
struct	mcap::MessageView
	Returned when iterating over Messages in a file, MessageView contains a reference to one Message, a pointer to its Channel, and an optional pointer to that Channel's Schema. The Channel pointer is guaranteed to be valid, while the Schema pointer may be null if the Channel references schema_id 0. More...

Namespaces
namespace	mcap

Macros
#define	MCAP_LIBRARY_VERSION   "2.1.0"

Typedefs
using	mcap::SchemaId = uint16_t
using	mcap::ChannelId = uint16_t
using	mcap::Timestamp = uint64_t
using	mcap::ByteOffset = uint64_t
using	mcap::KeyValueMap = std::unordered_map< std::string, std::string >
using	mcap::ByteArray = std::vector< std::byte >
using	mcap::ProblemCallback = std::function< void(const Status &)>
using	mcap::SchemaPtr = std::shared_ptr< Schema >
using	mcap::ChannelPtr = std::shared_ptr< Channel >

Enumerations
enum struct	mcap::Compression {   mcap::None ,   mcap::Lz4 ,   mcap::Zstd }
	Supported MCAP compression algorithms. More...
enum struct	mcap::CompressionLevel {   mcap::Fastest ,   mcap::Fast ,   mcap::Default ,   mcap::Slow ,   mcap::Slowest }
	Compression level to use when compression is enabled. Slower generally produces smaller files, at the expense of more CPU time. These levels map to different internal settings for each compression algorithm. More...
enum struct	mcap::OpCode : uint8_t {   mcap::Header = 0x01 ,   mcap::Footer = 0x02 ,   mcap::Schema = 0x03 ,   mcap::Channel = 0x04 ,   mcap::Message = 0x05 ,   mcap::Chunk = 0x06 ,   mcap::MessageIndex = 0x07 ,   mcap::ChunkIndex = 0x08 ,   mcap::Attachment = 0x09 ,   mcap::AttachmentIndex = 0x0A ,   mcap::Statistics = 0x0B ,   mcap::Metadata = 0x0C ,   mcap::MetadataIndex = 0x0D ,   mcap::SummaryOffset = 0x0E ,   mcap::DataEnd = 0x0F }
	MCAP record types. More...

Functions
MCAP_PUBLIC constexpr std::string_view	mcap::OpCodeString (OpCode opcode)
	Get the string representation of an OpCode.

Variables
constexpr char	mcap::SpecVersion = '0'
constexpr char	mcap::LibraryVersion [] = MCAP_LIBRARY_VERSION
constexpr uint8_t	mcap::Magic [] = {137, 77, 67, 65, 80, SpecVersion, 13, 10}
constexpr uint64_t	mcap::DefaultChunkSize = 1024 * 768
constexpr ByteOffset	mcap::EndOffset = std::numeric_limits<ByteOffset>::max()
constexpr Timestamp	mcap::MaxTime = std::numeric_limits<Timestamp>::max()

Macro Definition Documentation

MCAP_LIBRARY_VERSION

#define MCAP_LIBRARY_VERSION   "2.1.0"

Definition at line 17 of file types.hpp.