Module: Zstdlib

Defined in:
ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c,
ext/zstdlib_c/ruby/zlib-3.0/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.7/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.6/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.5/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.4/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.3/zstdlib.c,
ext/zstdlib_c/ruby/zlib-2.2/zstdlib.c

Defined Under Namespace

Classes: BufError, DataError, Deflate, Error, GzipFile, GzipReader, GzipWriter, InProgressError, 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+. If +string+ is an IO instance, reads from the IO until the IO returns nil and returns Adler-32 of all read data.

Example usage:

require "zstdlib"

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



466
467
468
469
470
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 466

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+.



483
484
485
486
487
488
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 483

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+. If +string+ is an IO instance, reads from the IO until the IO returns nil and returns CRC checksum of all read data.

FIXME: expression.



506
507
508
509
510
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 506

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+.



523
524
525
526
527
528
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 523

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.



538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 538

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



1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 1731

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) 


4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 4587

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) 


4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 4504

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



2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 2045

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.



385
386
387
388
389
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 385

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.



371
372
373
374
375
376
377
378
 
# File 'ext/zstdlib_c/ruby/zlib-3.1/zstdlib.c', line 371

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