file.h

using ouster::osf::ChunkBuffer = std::vector<uint8_t>: Chunk buffer type to store raw byte buffers of data.

enum class ouster::osf::OpenMode : uint8_t

Enum representing the available file opening modes.

Values:

enumerator READ: Open the file in read-only mode.

enumerator WRITE: Open the file in write-only mode. (CURRENTLY NOT SUPPORTED)

enum class ouster::osf::FileState : uint8_t

Enum representing the state of the OSF file.

Values:

enumerator GOOD: The file is good.

enumerator BAD: There is something wrong with the file.

class OsfFile

Interface to abstract the way of how we handle file system read/write operations.

Public Functions

explicit OsfFile(): Default constructor, sets most data to nullptr and 0.

explicit OsfFile(const std::string &filename, OpenMode mode = OpenMode::READ)

Opens the OSF file.

Note

Only OpenMode::READ is supported

Parameters:

filename – [in] The OSF file to open
mode – [in] The mode to open the file in, this argument is optional.

~OsfFile(): Cleans up any filebuffers/memory mapping.

uint64_t size() const

Returns the size of the OSF file.

Returns:: The size of the OSF file in bytes.

std::string filename() const

Returns the filename of the open OSF file.

Returns:: The filename of the open OSF file.

OSF_VERSION version()

Returns the version of the OSF file.

Returns:: The version of the OSF file.

uint64_t metadata_offset()

Returns the offset in the OSF file where the metadata section is located.

Throws:: std::logic_error – Exception on bad osf file.
Returns:: Offset to the metadata in bytes

uint64_t chunks_offset()

Returns the offset in the OSF file where the chunk section is located.

Throws:: std::logic_error – Exception on bad osf file.
Returns:: Offset to the chunks in bytes

bool valid()

Checks the validity of header and session/file_info blocks.

Returns:: If the header, session, and file_info blocks are valid.

bool good() const

Return the status of the OSF file.

Todo:: Need to have more states here (eod, valid, error, etc)

Returns:: If the OSF file is good or not.

uint64_t offset() const

Get the current offset in the OSF file.

Returns:: The current offset in the OSF file.

OsfFile &seek(uint64_t pos)

File seek (in mmap mode it’s just moving the offset_ pointer without any file system opeations.)

Throws:

std::logic_error – Exception on bad osf file.
std::out_of_range – Exception on out of range seek.

Parameters:

pos – [in] position in the file

Returns:

A reference to this object.

OsfFile &read(uint8_t *buf, const uint64_t count)

Read from file (in current mmap mode it’s copying data from mmap address to the ‘buf’ address).

Todo:: Handle errors in future and get the way to read them back with FileState etc.

Throws:

std::logic_error – Exception on bad osf file.
std::out_of_range – Exception on out of range read.

Parameters:

buf – [out] The buffer to write to.
count – [in] The number of bytes to write to buf.

Returns:

A reference to this object.

bool is_memory_mapped() const

Returns whether the OSF file is memory mapped or not.

Returns:: Is the OSF file memory mapped or not.

const uint8_t *buf(const uint64_t offset = 0) const

Mmap access to the file content with the specified offset from the beginning of the file.

Throws:

std::logic_error – Exception on bad osf file.
std::logic_error – Exception not being memory mapped.
std::out_of_range – Exception on out of range read.

Parameters:

offset – [in] The specified offset to access into the OSF file, this argument is optional.

Returns:

The pointer to the OSF file.

void close()

Clears file handle and allocated resources. In current mmap implementation it’s unmapping memory and essentially invalidates the memory addresses that might be captured within MessageRefs and Reader.