Module: Zstdlib

Defined in:
ext/zstdlib/ruby/zlib-2.7/zstdlib.c,
ext/zstdlib/ruby/zlib-2.6/zstdlib.c,
ext/zstdlib/ruby/zlib-2.5/zstdlib.c,
ext/zstdlib/ruby/zlib-2.4/zstdlib.c,
ext/zstdlib/ruby/zlib-2.3/zstdlib.c,
ext/zstdlib/ruby/zlib-2.2/zstdlib.c

Defined Under Namespace

Classes: BufError, DataError, Deflate, Error, GzipFile, GzipReader, GzipWriter, Inflate, MemError, NeedDict, StreamEnd, StreamError, VersionError, ZStream

Constant Summary collapse

VERSION =

The Ruby/zlib version string.

rb_str_new2(RUBY_ZLIB_VERSION)
ZLIB_VERSION =

The string which represents the version of zlib.h

rb_str_new2(ZLIB_VERSION)
ZSTD_VERSION = 
rb_str_new2(ZSTD_versionString())
BINARY =

:Deflate#data_type.

Represents binary data as guessed by deflate.

See Zstdlib
ASCII =

The underlying constant Z_ASCII was deprecated in favor of Z_TEXT in zlib 1.2.2. New applications should not use this constant.

See Zstdlib::Deflate#data_type.

Represents text data as guessed by deflate.

NOTE
TEXT =

:Deflate#data_type.

Represents text data as guessed by deflate.

See Zstdlib
UNKNOWN =

:Deflate#data_type.

Represents an unknown data type as guessed by deflate.

See Zstdlib
NO_COMPRESSION =

No compression, passes through data untouched. Use this for appending pre-compressed data to a deflate stream.

INT2FIX(Z_NO_COMPRESSION)
BEST_SPEED =

Fastest compression level, but with with lowest space savings.

INT2FIX(Z_BEST_SPEED)
BEST_COMPRESSION =

Slowest compression level, but with the best space savings.

INT2FIX(ZSTD_maxCLevel())
DEFAULT_COMPRESSION =

Default compression level which is a good trade-off between space and time

INT2FIX(ZSTD_CLEVEL_DEFAULT)
FILTERED =

Deflate strategy for data produced by a filter (or predictor). The effect of FILTERED is to force more Huffman codes and less string matching; it is somewhat intermediate between DEFAULT_STRATEGY and HUFFMAN_ONLY. Filtered data consists mostly of small values with a somewhat random distribution.

INT2FIX(Z_FILTERED)
HUFFMAN_ONLY =

Deflate strategy which uses Huffman codes only (no string matching).

INT2FIX(Z_HUFFMAN_ONLY)
RLE =

Deflate compression strategy designed to be almost as fast as HUFFMAN_ONLY, but give better compression for PNG image data.

INT2FIX(Z_RLE)
FIXED =

Deflate strategy which prevents the use of dynamic Huffman codes, allowing for a simpler decoder for specialized applications.

INT2FIX(Z_FIXED)
DEFAULT_STRATEGY =

Default deflate strategy which is used for normal data.

INT2FIX(Z_DEFAULT_STRATEGY)
MAX_WBITS =

:Inflate.new for details.

The maximum size of the zlib history buffer.  Note that zlib allows
larger values to enable different inflate modes.  See Zstdlib
DEF_MEM_LEVEL =

The default memory level for allocating zlib deflate compression state.

INT2FIX(DEF_MEM_LEVEL)
MAX_MEM_LEVEL =

The maximum memory level for allocating zlib deflate compression state.

INT2FIX(MAX_MEM_LEVEL)
NO_FLUSH =

NO_FLUSH is the default flush method and allows deflate to decide how much data to accumulate before producing output in order to maximize compression.

INT2FIX(Z_NO_FLUSH)
SYNC_FLUSH =

The SYNC_FLUSH method flushes all pending output to the output buffer and the output is aligned on a byte boundary. Flushing may degrade compression so it should be used only when necessary, such as at a request or response boundary for a network stream.

INT2FIX(Z_SYNC_FLUSH)
FULL_FLUSH =

Flushes all output as with SYNC_FLUSH, and the compression state is reset so that decompression can restart from this point if previous compressed data has been damaged or if random access is desired. Like SYNC_FLUSH, using FULL_FLUSH too often can seriously degrade compression.

INT2FIX(Z_FULL_FLUSH)
FINISH =

Processes all pending input and flushes pending output.

INT2FIX(Z_FINISH)
OS_CODE =

The OS code of current host

INT2FIX(OS_CODE)
OS_MSDOS =

OS code for MSDOS hosts

INT2FIX(OS_MSDOS)
OS_AMIGA =

OS code for Amiga hosts

INT2FIX(OS_AMIGA)
OS_VMS =

OS code for VMS hosts

INT2FIX(OS_VMS)
OS_UNIX =

OS code for UNIX hosts

INT2FIX(OS_UNIX)
OS_ATARI =

OS code for Atari hosts

INT2FIX(OS_ATARI)
OS_OS2 =

OS code for OS2 hosts

INT2FIX(OS_OS2)
OS_MACOS =

OS code for Mac OS hosts

INT2FIX(OS_MACOS)
OS_TOPS20 =

OS code for TOPS-20 hosts

INT2FIX(OS_TOPS20)
OS_WIN32 =

OS code for Win32 hosts

INT2FIX(OS_WIN32)
OS_VMCMS =

OS code for VM OS hosts

INT2FIX(OS_VMCMS)
OS_ZSYSTEM =

OS code for Z-System hosts

INT2FIX(OS_ZSYSTEM)
OS_CPM =

OS code for CP/M hosts

INT2FIX(OS_CPM)
OS_QDOS =

OS code for QDOS hosts

INT2FIX(OS_QDOS)
OS_RISCOS =

OS code for RISC OS hosts

INT2FIX(OS_RISCOS)
OS_UNKNOWN =

OS code for unknown hosts

INT2FIX(OS_UNKNOWN)

Class Method Summary collapse

Class Method Details

.adler32(*args) ⇒ Object

call-seq: Zstdlib.adler32(string, adler)

Calculates Adler-32 checksum for +string+, and returns updated value of +adler+. If +string+ is omitted, it returns the Adler-32 initial value. If +adler+ is omitted, it assumes that the initial value is given to +adler+.

Example usage:

require "zstdlib"

data = "foo" puts "Adler32 checksum: #Zstdlib.adler32(data).to_s(16)" #=> Adler32 checksum: 2820145



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 449

static VALUE
rb_zlib_adler32(int argc, VALUE *argv, VALUE klass)
{
    return do_checksum(argc, argv, adler32);
}

.adler32_combine(adler1, adler2, len2) ⇒ Object

call-seq: Zstdlib.adler32_combine(adler1, adler2, len2)

Combine two Adler-32 check values in to one. +alder1+ is the first Adler-32 value, +adler2+ is the second Adler-32 value. +len2+ is the length of the string used to generate +adler2+.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 466

static VALUE
rb_zlib_adler32_combine(VALUE klass, VALUE adler1, VALUE adler2, VALUE len2)
{
    return ULONG2NUM(
	adler32_combine(NUM2ULONG(adler1), NUM2ULONG(adler2), NUM2LONG(len2)));
}

.crc32(*args) ⇒ Object

call-seq: Zstdlib.crc32(string, crc)

Calculates CRC checksum for +string+, and returns updated value of +crc+. If +string+ is omitted, it returns the CRC initial value. If +crc+ is omitted, it assumes that the initial value is given to +crc+.

FIXME: expression.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 487

static VALUE
rb_zlib_crc32(int argc, VALUE *argv, VALUE klass)
{
    return do_checksum(argc, argv, crc32);
}

.crc32_combine(crc1, crc2, len2) ⇒ Object

call-seq: Zstdlib.crc32_combine(crc1, crc2, len2)

Combine two CRC-32 check values in to one. +crc1+ is the first CRC-32 value, +crc2+ is the second CRC-32 value. +len2+ is the length of the string used to generate +crc2+.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 504

static VALUE
rb_zlib_crc32_combine(VALUE klass, VALUE crc1, VALUE crc2, VALUE len2)
{
    return ULONG2NUM(
	crc32_combine(NUM2ULONG(crc1), NUM2ULONG(crc2), NUM2LONG(len2)));
}

.crc_table ⇒ Object

Returns the table for calculating CRC checksum as an array.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 519

static VALUE
rb_zlib_crc_table(VALUE obj)
{
#if !defined(HAVE_TYPE_Z_CRC_T)
    /* z_crc_t is defined since zlib-1.2.7. */
    typedef unsigned long z_crc_t;
#endif
    const z_crc_t *crctbl;
    VALUE dst;
    int i;

    crctbl = get_crc_table();
    dst = rb_ary_new2(256);

    for (i = 0; i < 256; i++) {
	rb_ary_push(dst, rb_uint2inum(crctbl[i]));
    }
    return dst;
}

.deflate(*args) ⇒ Object

call-seq: Zstdlib.deflate(string[, level]) Zstdlib::Deflate.deflate(string[, level])

Compresses the given +string+. Valid values of level are Zstdlib::NO_COMPRESSION, Zstdlib::BEST_SPEED, Zstdlib::BEST_COMPRESSION, Zstdlib::DEFAULT_COMPRESSION, or an integer from 0 to 9.

This method is almost equivalent to the following code:

def deflate(string, level) z = Zstdlib::Deflate.new(level) dst = z.deflate(string, Zstdlib::FINISH) z.close dst end

See also Zstdlib.inflate



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 1644

static VALUE
rb_deflate_s_deflate(int argc, VALUE *argv, VALUE klass)
{
    struct zstream z;
    VALUE src, level, dst, args[2];
    int err, lev;

    rb_scan_args(argc, argv, "11", &src, &level);

    lev = ARG_LEVEL(level);
    StringValue(src);
    zstream_init_deflate(&z);
    err = deflateInit(&z.stream, lev);
    if (err != Z_OK) {
	raise_zlib_error(err, z.stream.msg);
    }
    ZSTREAM_READY(&z);

    args[0] = (VALUE)&z;
    args[1] = src;
    dst = rb_ensure(deflate_run, (VALUE)args, zstream_ensure_end, (VALUE)&z);

    return dst;
}

.gunzip(src) ⇒ String

Decode the given gzipped +string+.

This method is almost equivalent to the following code:

def gunzip(string) sio = StringIO.new(string) gz = Zstdlib::GzipReader.new(sio, encoding: Encoding::ASCII_8BIT) gz.read ensure gz&.close end

See also Zstdlib.gzip

Returns:

  • (String) 


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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 4426

static VALUE
zlib_gunzip(VALUE klass, VALUE src)
{
    struct gzfile gz0;
    struct gzfile *gz = &gz0;
    int err;

    StringValue(src);

    gzfile_init(gz, &inflate_funcs, zlib_gunzip_end);
    err = inflateInit2(&gz->z.stream, -MAX_WBITS);
    if (err != Z_OK) {
	raise_zlib_error(err, gz->z.stream.msg);
    }
    gz->io = Qundef;
    gz->z.input = src;
    ZSTREAM_READY(&gz->z);
    return rb_ensure(zlib_gunzip_run, (VALUE)gz, zlib_gzip_ensure, (VALUE)gz);
}

.gzip(src, level: nil, strategy: nil) ⇒ String

Gzip the given +string+. Valid values of level are Zstdlib::NO_COMPRESSION, Zstdlib::BEST_SPEED, Zstdlib::BEST_COMPRESSION, Zstdlib::DEFAULT_COMPRESSION (default), or an integer from 0 to 9.

This method is almost equivalent to the following code:

def gzip(string, level: nil, strategy: nil) sio = StringIO.new sio.binmode gz = Zstdlib::GzipWriter.new(sio, level, strategy) gz.write(string) gz.close sio.string end

See also Zstdlib.gunzip

Returns:

  • (String) 


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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 4343

static VALUE
zlib_s_gzip(int argc, VALUE *argv, VALUE klass)
{
    struct gzfile gz0;
    struct gzfile *gz = &gz0;
    int err;
    VALUE src, opts, level=Qnil, strategy=Qnil, args[2];

    if (OPTHASH_GIVEN_P(opts)) {
	ID keyword_ids[2];
	VALUE kwargs[2];
	keyword_ids[0] = id_level;
	keyword_ids[1] = id_strategy;
	rb_get_kwargs(opts, keyword_ids, 0, 2, kwargs);
	if (kwargs[0] != Qundef) {
	    level = kwargs[0];
	}
	if (kwargs[1] != Qundef) {
	    strategy = kwargs[1];
	}
    }
    rb_scan_args(argc, argv, "10", &src);
    StringValue(src);
    gzfile_init(gz, &deflate_funcs, zlib_gzip_end);
    gz->level = ARG_LEVEL(level);
    err = deflateInit2(&gz->z.stream, gz->level, Z_DEFLATED,
		       -MAX_WBITS, DEF_MEM_LEVEL, ARG_STRATEGY(strategy));
    if (err != Z_OK) {
	zlib_gzip_end(gz);
	raise_zlib_error(err, gz->z.stream.msg);
    }
    ZSTREAM_READY(&gz->z);
    args[0] = (VALUE)gz;
    args[1] = src;
    return rb_ensure(zlib_gzip_run, (VALUE)args, zlib_gzip_ensure, (VALUE)gz);
}

.inflate(src) ⇒ Object

call-seq: Zstdlib.inflate(string) Zstdlib::Inflate.inflate(string)

Decompresses +string+. Raises a Zstdlib::NeedDict exception if a preset dictionary is needed for decompression.

This method is almost equivalent to the following code:

def inflate(string) zstream = Zstdlib::Inflate.new buf = zstream.inflate(string) zstream.finish zstream.close buf end

See also Zstdlib.deflate



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 1958

static VALUE
rb_inflate_s_inflate(VALUE obj, VALUE src)
{
    struct zstream z;
    VALUE dst, args[2];
    int err;

    StringValue(src);
    zstream_init_inflate(&z);
    err = inflateInit(&z.stream);
    if (err != Z_OK) {
	raise_zlib_error(err, z.stream.msg);
    }
    ZSTREAM_READY(&z);

    args[0] = (VALUE)&z;
    args[1] = src;
    dst = rb_ensure(inflate_run, (VALUE)args, zstream_ensure_end, (VALUE)&z);

    return dst;
}

.zlib_version ⇒ Object

Returns the string which represents the version of zlib library.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 379

static VALUE
rb_zlib_version(VALUE klass)
{
    return rb_str_new2(zlibVersion());
}

.zstd_version ⇒ Object

Returns the string which represents the version of zstd library.



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# File 'ext/zstdlib/ruby/zlib-2.7/zstdlib.c', line 365

static VALUE 
rb_zstd_version(VALUE klass) 
{ 
    VALUE str; 
    str = rb_str_new2(ZSTD_versionString()); 
    OBJ_TAINT(str); 
    return str; 
}