Input stream classes: Apache Arrow GLib Reference Manual

Input stream classes

Functions

gboolean	garrow_input_stream_advance ()
gboolean	garrow_input_stream_align ()
GArrowTensor *	garrow_input_stream_read_tensor ()
GArrowRecordBatch *	garrow_input_stream_read_record_batch ()
guint64	garrow_seekable_input_stream_get_size ()
gboolean	garrow_seekable_input_stream_get_support_zero_copy ()
GArrowBuffer *	garrow_seekable_input_stream_read_at ()
GBytes *	garrow_seekable_input_stream_read_at_bytes ()
GBytes *	garrow_seekable_input_stream_peek ()
GArrowBufferInputStream *	garrow_buffer_input_stream_new ()
GArrowBuffer *	garrow_buffer_input_stream_get_buffer ()
GArrowMemoryMappedInputStream *	garrow_memory_mapped_input_stream_new ()
GArrowGIOInputStream *	garrow_gio_input_stream_new ()
GInputStream *	garrow_gio_input_stream_get_raw ()
GArrowCompressedInputStream *	garrow_compressed_input_stream_new ()

Properties

GInputStream *	raw	Read / Write / Construct Only
GArrowBuffer *	buffer	Read / Write / Construct Only
GArrowCodec *	codec	Read / Write / Construct Only
GArrowInputStream *	raw	Read / Write / Construct Only
gpointer	input-stream	Write / Construct Only

Types and Values

#define	GARROW_TYPE_INPUT_STREAM
struct	GArrowInputStreamClass
#define	GARROW_TYPE_SEEKABLE_INPUT_STREAM
struct	GArrowSeekableInputStreamClass
#define	GARROW_TYPE_BUFFER_INPUT_STREAM
struct	GArrowBufferInputStreamClass
struct	GArrowMemoryMappedInputStream
struct	GArrowGIOInputStream
#define	GARROW_TYPE_COMPRESSED_INPUT_STREAM
struct	GArrowCompressedInputStreamClass
	GArrowBufferInputStream
	GArrowCompressedInputStream
	GArrowInputStream
	GArrowSeekableInputStream

Object Hierarchy

    GObject
    ╰── GInputStream
        ╰── GArrowInputStream
            ├── GArrowSeekableInputStream
            │   ├── GArrowBufferInputStream
            │   ├── GArrowGIOInputStream
            │   ╰── GArrowMemoryMappedInputStream
            ├── GArrowCompressedInputStream
            ├── GArrowCompressedInputStream
            ╰── GArrowSeekableInputStream
                ├── GArrowBufferInputStream
                │   ╰── GArrowCUDABufferInputStream
                ├── GArrowGIOInputStream
                ╰── GArrowMemoryMappedInputStream

Implemented Interfaces

GArrowMemoryMappedInputStream implements GArrowFile and GArrowReadable.

GArrowGIOInputStream implements GArrowFile and GArrowReadable.

GArrowBufferInputStream implements GArrowFile and GArrowReadable.

GArrowCompressedInputStream implements GArrowFile and GArrowReadable.

GArrowInputStream implements GArrowFile and GArrowReadable.

GArrowSeekableInputStream implements GArrowFile and GArrowReadable.

Includes

#include <arrow-glib/arrow-glib.h>

Description

GArrowInputStream is a base class for input stream.

GArrowSeekableInputStream is a base class for input stream that supports random access.

GArrowBufferInputStream is a class to read data on buffer.

GArrowMemoryMappedInputStream is a class to read data in file by mapping the file on memory. It supports zero copy.

GArrowGIOInputStream is a class for GInputStream based input stream.

GArrowCompressedInputStream is a class to read data from compressed input stream.

Functions

garrow_input_stream_advance ()

gboolean
garrow_input_stream_advance (GArrowInputStream *input_stream,
                             gint64 n_bytes,
                             GError **error);

Parameters

input_stream	A GArrowInputStream.
n_bytes	The number of bytes to be advanced.
error	Return location for a GError or `NULL`.	[nullable]

Returns

TRUE on success, FALSE on error.

Since: 0.11.0

garrow_input_stream_align ()

gboolean
garrow_input_stream_align (GArrowInputStream *input_stream,
                           gint32 alignment,
                           GError **error);

Parameters

input_stream	A GArrowInputStream.
alignment	The byte multiple for the metadata prefix, usually 8 or 64, to ensure the body starts on a multiple of that alignment.
error	Return location for a GError or `NULL`.	[nullable]

Returns

TRUE on success, FALSE on error.

Since: 0.11.0

garrow_input_stream_read_tensor ()

GArrowTensor *
garrow_input_stream_read_tensor (GArrowInputStream *input_stream,
                                 GError **error);

Parameters

input_stream	A GArrowInputStream.
error	Return location for a GError or `NULL`.	[nullable]

Returns

GArrowTensor on success, NULL on error.

[transfer full][nullable]

Since: 0.11.0

garrow_input_stream_read_record_batch ()

GArrowRecordBatch *
garrow_input_stream_read_record_batch (GArrowInputStream *input_stream,
                                       GArrowSchema *schema,
                                       GArrowReadOptions *options,
                                       GError **error);

Parameters

input_stream	A GArrowInputStream.
schema	A GArrowSchema for a read record batch.
options	A GArrowReadOptions.	[nullable]
error	Return location for a GError or `NULL`.	[nullable]

Returns

GArrowRecordBatch on success, NULL on error.

[transfer full][nullable]

Since: 1.0.0

garrow_seekable_input_stream_get_size ()

guint64
garrow_seekable_input_stream_get_size (GArrowSeekableInputStream *input_stream,
                                       GError **error);

Parameters

input_stream	A GArrowSeekableInputStream.
error	Return location for a GError or `NULL`.	[nullable]

Returns

The size of the file.

garrow_seekable_input_stream_get_support_zero_copy ()

gboolean
garrow_seekable_input_stream_get_support_zero_copy
                               (GArrowSeekableInputStream *input_stream);

Parameters

input_stream

A GArrowSeekableInputStream.

Returns

Whether zero copy read is supported or not.

garrow_seekable_input_stream_read_at ()

GArrowBuffer *
garrow_seekable_input_stream_read_at (GArrowSeekableInputStream *input_stream,
                                      gint64 position,
                                      gint64 n_bytes,
                                      GError **error);

Parameters

input_stream	A GArrowSeekableInputStream.
position	The read start position.
n_bytes	The number of bytes to be read.
error	Return location for a GError or `NULL`.	[nullable]

Returns

GArrowBuffer that has read data on success, NULL if there was an error.

[transfer full][nullable]

garrow_seekable_input_stream_read_at_bytes ()

GBytes *
garrow_seekable_input_stream_read_at_bytes
                               (GArrowSeekableInputStream *input_stream,
                                gint64 position,
                                gint64 n_bytes,
                                GError **error);

Parameters

input_stream	A GArrowSeekableInputStream.
position	The read start position.
n_bytes	The number of bytes to be read.
error	Return location for a GError or `NULL`.	[nullable]

Returns

GBytes that has read data on success, NULL if there was an error.

[transfer full][nullable]

Since: 0.15.0

garrow_seekable_input_stream_peek ()

GBytes *
garrow_seekable_input_stream_peek (GArrowSeekableInputStream *input_stream,
                                   gint64 n_bytes,
                                   GError **error);

Parameters

input_stream	A GArrowSeekableInputStream.
n_bytes	The number of bytes to be peeked.
error	Return location for a GError or `NULL`.	[nullable]

Returns

The data of the buffer, up to the indicated number. The data becomes invalid after any operation on the stream. If the stream is unbuffered, the data is empty.

It should be freed with g_bytes_unref() when no longer needed.

[transfer full]

Since: 0.12.0

garrow_buffer_input_stream_new ()

GArrowBufferInputStream *
garrow_buffer_input_stream_new (GArrowBuffer *buffer);

Parameters

buffer

The buffer to be read.

Returns

A newly created GArrowBufferInputStream.

garrow_buffer_input_stream_get_buffer ()

GArrowBuffer *
garrow_buffer_input_stream_get_buffer (GArrowBufferInputStream *input_stream);

Parameters

input_stream

A GArrowBufferInputStream.

Returns

The data of the stream as GArrowBuffer.

[transfer full]

garrow_memory_mapped_input_stream_new ()

GArrowMemoryMappedInputStream *
garrow_memory_mapped_input_stream_new (const gchar *path,
                                       GError **error);

Parameters

path	The path of the file to be mapped on memory.
error	Return location for a GError or `NULL`.	[nullable]

Returns

A newly created GArrowMemoryMappedInputStream or NULL on error.

[nullable]

garrow_gio_input_stream_new ()

GArrowGIOInputStream *
garrow_gio_input_stream_new (GInputStream *gio_input_stream);

Parameters

gio_input_stream

The stream to be read.

Returns

A newly created GArrowGIOInputStream.

[transfer full]

Since: 0.5.0

garrow_gio_input_stream_get_raw ()

GInputStream *
garrow_gio_input_stream_get_raw (GArrowGIOInputStream *input_stream);

garrow_gio_input_stream_get_raw has been deprecated since version 0.12.0 and should not be used in newly-written code.

Use GArrowGIOInputStream::raw property instead.

Parameters

input_stream

A GArrowGIOInputStream.

Returns

The wrapped GInputStream.

[transfer none]

Since: 0.5.0

garrow_compressed_input_stream_new ()

GArrowCompressedInputStream *
garrow_compressed_input_stream_new (GArrowCodec *codec,
                                    GArrowInputStream *raw,
                                    GError **error);

Parameters

codec	A GArrowCodec for compressed data in the `raw` .
raw	A GArrowInputStream that contains compressed data.
error	Return location for a GError or `NULL`.	[nullable]

Returns

A newly created GArrowCompressedInputStream.

Since: 0.12.0

Types and Values

GARROW_TYPE_INPUT_STREAM

#define GARROW_TYPE_INPUT_STREAM (garrow_input_stream_get_type())

struct GArrowInputStreamClass

struct GArrowInputStreamClass {
  GInputStreamClass parent_class;
};

GARROW_TYPE_SEEKABLE_INPUT_STREAM

#define             GARROW_TYPE_SEEKABLE_INPUT_STREAM

struct GArrowSeekableInputStreamClass

struct GArrowSeekableInputStreamClass {
  GArrowInputStreamClass parent_class;
};

GARROW_TYPE_BUFFER_INPUT_STREAM

#define             GARROW_TYPE_BUFFER_INPUT_STREAM

struct GArrowBufferInputStreamClass

struct GArrowBufferInputStreamClass {
  GArrowSeekableInputStreamClass parent_class;
};

struct GArrowMemoryMappedInputStream

struct GArrowMemoryMappedInputStream;

It wraps arrow::io::MemoryMappedFile.

struct GArrowGIOInputStream

struct GArrowGIOInputStream;

It's an input stream for GInputStream.

GARROW_TYPE_COMPRESSED_INPUT_STREAM

#define             GARROW_TYPE_COMPRESSED_INPUT_STREAM

struct GArrowCompressedInputStreamClass

struct GArrowCompressedInputStreamClass {
  GArrowInputStreamClass parent_class;
};

GArrowBufferInputStream

typedef struct _GArrowBufferInputStream GArrowBufferInputStream;

GArrowCompressedInputStream

typedef struct _GArrowCompressedInputStream GArrowCompressedInputStream;

GArrowInputStream

typedef struct _GArrowInputStream GArrowInputStream;

GArrowSeekableInputStream

typedef struct _GArrowSeekableInputStream GArrowSeekableInputStream;

Property Details

The `“raw”` property

  “raw”                      GInputStream *

The raw GInputStream *.

Flags: Read / Write / Construct Only

The `“buffer”` property

  “buffer”                   GArrowBuffer *

The data.

Flags: Read / Write / Construct Only

The `“codec”` property

  “codec”                    GArrowCodec *

The codec for the stream.

Flags: Read / Write / Construct Only

The `“raw”` property

  “raw”                      GArrowInputStream *

The underlying raw input stream.

Flags: Read / Write / Construct Only

The `“input-stream”` property

  “input-stream”             gpointer

The raw std::shared<arrow::io::InputStream> *.

Flags: Write / Construct Only