spinn_storage_handlers.abstract_classes package

Submodules

spinn_storage_handlers.abstract_classes.abstract_buffered_data_storage module

class spinn_storage_handlers.abstract_classes.abstract_buffered_data_storage.AbstractBufferedDataStorage

Bases: object

An object that can store and read back buffered data.

close()

Closes the data storage.

Return type:None Raises:spinn_storage_handlers.exceptions.DataReadException – If the data storage cannot be closed

eof()

Check if the read pointer is a the end of the data storage.

Returns:Whether the read pointer is at the end of the data storage Return type:bool

read(data_size)

Read data from the data storage from the position indicated by the read pointer index.

Parameters:data_size (int) – number of bytes to be read Returns:a bytearray containing the data read Return type:bytearray

read_all()

Read all the data contained in the data storage starting from position 0 to the end.

Returns:a bytearray containing the data read Return type:bytearray

readinto(data)

Read some bytes of data from the underlying storage into a predefined array. Will block until some bytes are available, but may not fill the array completely.

Parameters:data (bytearray) – The place where the data is to be stored Returns:The number of bytes stored in data Return type:int Raises:IOError – If an error occurs reading from the underlying storage

seek_read(offset, whence=0)

Set the data storage’s current read position to the offset.

Parameters:

• offset (int) – Position of the read pointer within the buffer
• whence – One of: * os.SEEK_SET which means absolute buffer positioning (default) * os.SEEK_CUR which means seek relative to the current read position * os.SEEK_END which means seek relative to the buffer’s end

Return type:

None

seek_write(offset, whence=0)

Set the data storage’s current write position to the offset.

Parameters:

• offset (int) – Position of the write pointer within the buffer
• whence – One of: * os.SEEK_SET which means absolute buffer positioning (default) * os.SEEK_CUR which means seek relative to the current write position * os.SEEK_END which means seek relative to the buffer’s end

Return type:

None

tell_read()

The current position of the read pointer.

Returns:The current position of the read pointer Return type:int

tell_write()

The current position of the write pointer.

Returns:The current position of the write pointer Return type:int

write(data)

Store data in the data storage in the position indicated by the write pointer index.

Parameters:data (bytearray) – the data to be stored Return type:None

spinn_storage_handlers.abstract_classes.abstract_byte_reader module

class spinn_storage_handlers.abstract_classes.abstract_byte_reader.AbstractByteReader

Bases: object

An abstract reader of bytes.

Note

Due to endianness concerns, the methods of this reader should be used directly for the appropriate data type being read; e.g. an int should be written using read_int rather than calling read_byte 4 times, unless a specific endianness is being achieved.

is_at_end()

Indicates whether the reader is currently at the end of the byte reader.

Returns:whether the reader is currently at the end of the byte reader. Return type:bool

read_byte()

Reads the next byte.

Returns:

A byte

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are no more bytes to read

read_bytes(size=None)

Reads an array of bytes.

Parameters:

size (int or None) – The number of bytes to read, or None to read all of the remaining bytes.

Returns:

An array of bytes

Return type:

bytearray

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read the requested size. Note that if there are no more bytes and size is None, an empty array will be returned

read_int()

Read the next four bytes as in int value.

Returns:

An int

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read an int

read_long()

Reads the next eight bytes as an int value.

Returns:

An int

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read an int

read_short()

Reads the next two bytes as a short value.

Returns:

A short

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read a short

spinn_storage_handlers.abstract_classes.abstract_byte_writer module

class spinn_storage_handlers.abstract_classes.abstract_byte_writer.AbstractByteWriter

Bases: object

An abstract writer of bytes.

Note

Due to endianness concerns, the methods of this writer should be used directly for the appropriate data type being written; e.g. an int should be written using write_int rather than calling write_byte 4 times with the bytes of the int, unless a specific endianness is being achieved.

get_n_bytes_written()

Determines how many bytes have been written in total.

Returns:The number of bytes written Return type:int Raises:None – Does not raise exceptions

write_byte(byte_value)

Writes the lowest order byte of the given value.

Parameters:byte_value (int) – The byte to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_bytes(byte_iterable)

Writes a set of bytes.

Parameters:byte_iterable (bytes or bytearray or iterable(bytes or bytearray)) – The bytes to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_int(int_value)

Writes a four byte value.

Parameters:int_value (int) – The integer to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_long(long_value)

Writes an eight byte value.

Parameters:long_value (int) – The 64-bit int to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_short(short_value)

Writes the two lowest order bytes of the given value.

Parameters:short_value (int) – The short to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

spinn_storage_handlers.abstract_classes.abstract_context_manager module

class spinn_storage_handlers.abstract_classes.abstract_context_manager.AbstractContextManager

Bases: object

Closeable class that supports being used as a simple context manager.

close()

How to actually close the underlying resources.

spinn_storage_handlers.abstract_classes.abstract_data_reader module

class spinn_storage_handlers.abstract_classes.abstract_data_reader.AbstractDataReader

Bases: object

Abstract reader used to read data from somewhere.

read(n_bytes)

Read some bytes of data from the underlying storage. Will block until some bytes are available, but might not return the full n_bytes. The size of the returned array indicates how many bytes were read.

Parameters:n_bytes (int) – The number of bytes to read Returns:An array of bytes Return type:bytearray Raises:IOError – If an error occurs reading from the underlying storage

readall()

Read the rest of the bytes from the underlying stream.

Returns:The bytes read Return type:bytearray Raises:IOError – If there is an error obtaining the bytes

readinto(data)

Read some bytes of data from the underlying storage into a predefined array. Will block until some bytes are available, but may not fill the array completely.

Parameters:data (bytearray) – The place where the data is to be stored Returns:The number of bytes stored in data Return type:int Raises:IOError – If an error occurs reading from the underlying storage

tell()

Returns the position of the file cursor.

Returns:Position of the file cursor Return type:int

spinn_storage_handlers.abstract_classes.abstract_data_writer module

class spinn_storage_handlers.abstract_classes.abstract_data_writer.AbstractDataWriter

Bases: object

Abstract writer used to write data somewhere.

tell()

Returns the position of the file cursor.

Returns:Position of the file cursor Return type:int

write(data)

Write some bytes of data to the underlying storage. Does not return until all the bytes have been written.

Parameters:data (bytearray or bytes) – The data to write Returns:Nothing is returned Return type:None Raises:IOError – If an error occurs writing to the underlying storage

Module contents

class spinn_storage_handlers.abstract_classes.AbstractBufferedDataStorage

Bases: object

An object that can store and read back buffered data.

close()

Closes the data storage.

Return type:None Raises:spinn_storage_handlers.exceptions.DataReadException – If the data storage cannot be closed

eof()

Check if the read pointer is a the end of the data storage.

Returns:Whether the read pointer is at the end of the data storage Return type:bool

read(data_size)

Read data from the data storage from the position indicated by the read pointer index.

Parameters:data_size (int) – number of bytes to be read Returns:a bytearray containing the data read Return type:bytearray

read_all()

Read all the data contained in the data storage starting from position 0 to the end.

Returns:a bytearray containing the data read Return type:bytearray

readinto(data)

Read some bytes of data from the underlying storage into a predefined array. Will block until some bytes are available, but may not fill the array completely.

Parameters:data (bytearray) – The place where the data is to be stored Returns:The number of bytes stored in data Return type:int Raises:IOError – If an error occurs reading from the underlying storage

seek_read(offset, whence=0)

Set the data storage’s current read position to the offset.

Parameters:

• offset (int) – Position of the read pointer within the buffer
• whence – One of: * os.SEEK_SET which means absolute buffer positioning (default) * os.SEEK_CUR which means seek relative to the current read position * os.SEEK_END which means seek relative to the buffer’s end

Return type:

None

seek_write(offset, whence=0)

Set the data storage’s current write position to the offset.

Parameters:

• offset (int) – Position of the write pointer within the buffer
• whence – One of: * os.SEEK_SET which means absolute buffer positioning (default) * os.SEEK_CUR which means seek relative to the current write position * os.SEEK_END which means seek relative to the buffer’s end

Return type:

None

tell_read()

The current position of the read pointer.

Returns:The current position of the read pointer Return type:int

tell_write()

The current position of the write pointer.

Returns:The current position of the write pointer Return type:int

write(data)

Store data in the data storage in the position indicated by the write pointer index.

Parameters:data (bytearray) – the data to be stored Return type:None

class spinn_storage_handlers.abstract_classes.AbstractByteReader

Bases: object

An abstract reader of bytes.

Note

Due to endianness concerns, the methods of this reader should be used directly for the appropriate data type being read; e.g. an int should be written using read_int rather than calling read_byte 4 times, unless a specific endianness is being achieved.

is_at_end()

Indicates whether the reader is currently at the end of the byte reader.

Returns:whether the reader is currently at the end of the byte reader. Return type:bool

read_byte()

Reads the next byte.

Returns:

A byte

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are no more bytes to read

read_bytes(size=None)

Reads an array of bytes.

Parameters:

size (int or None) – The number of bytes to read, or None to read all of the remaining bytes.

Returns:

An array of bytes

Return type:

bytearray

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read the requested size. Note that if there are no more bytes and size is None, an empty array will be returned

read_int()

Read the next four bytes as in int value.

Returns:

An int

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read an int

read_long()

Reads the next eight bytes as an int value.

Returns:

An int

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read an int

read_short()

Reads the next two bytes as a short value.

Returns:

A short

Return type:

int

Raises:

• IOError – If there is an error reading from the stream
• EOFError – If there are too few bytes to read a short

class spinn_storage_handlers.abstract_classes.AbstractByteWriter

Bases: object

An abstract writer of bytes.

Note

Due to endianness concerns, the methods of this writer should be used directly for the appropriate data type being written; e.g. an int should be written using write_int rather than calling write_byte 4 times with the bytes of the int, unless a specific endianness is being achieved.

get_n_bytes_written()

Determines how many bytes have been written in total.

Returns:The number of bytes written Return type:int Raises:None – Does not raise exceptions

write_byte(byte_value)

Writes the lowest order byte of the given value.

Parameters:byte_value (int) – The byte to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_bytes(byte_iterable)

Writes a set of bytes.

Parameters:byte_iterable (bytes or bytearray or iterable(bytes or bytearray)) – The bytes to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_int(int_value)

Writes a four byte value.

Parameters:int_value (int) – The integer to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_long(long_value)

Writes an eight byte value.

Parameters:long_value (int) – The 64-bit int to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

write_short(short_value)

Writes the two lowest order bytes of the given value.

Parameters:short_value (int) – The short to write Returns:Nothing is returned Return type:None Raises:IOError – If there is an error writing to the stream

class spinn_storage_handlers.abstract_classes.AbstractContextManager

Bases: object

Closeable class that supports being used as a simple context manager.

close()

How to actually close the underlying resources.

class spinn_storage_handlers.abstract_classes.AbstractDataReader

Bases: object

Abstract reader used to read data from somewhere.

read(n_bytes)

Read some bytes of data from the underlying storage. Will block until some bytes are available, but might not return the full n_bytes. The size of the returned array indicates how many bytes were read.

Parameters:n_bytes (int) – The number of bytes to read Returns:An array of bytes Return type:bytearray Raises:IOError – If an error occurs reading from the underlying storage

readall()

Read the rest of the bytes from the underlying stream.

Returns:The bytes read Return type:bytearray Raises:IOError – If there is an error obtaining the bytes

readinto(data)

Read some bytes of data from the underlying storage into a predefined array. Will block until some bytes are available, but may not fill the array completely.

Parameters:data (bytearray) – The place where the data is to be stored Returns:The number of bytes stored in data Return type:int Raises:IOError – If an error occurs reading from the underlying storage

tell()

Returns the position of the file cursor.

Returns:Position of the file cursor Return type:int

class spinn_storage_handlers.abstract_classes.AbstractDataWriter

Bases: object

Abstract writer used to write data somewhere.

tell()

Returns the position of the file cursor.

Returns:Position of the file cursor Return type:int

write(data)

Write some bytes of data to the underlying storage. Does not return until all the bytes have been written.

Parameters:data (bytearray or bytes) – The data to write Returns:Nothing is returned Return type:None Raises:IOError – If an error occurs writing to the underlying storage