Zlib:Inflate is the class for decompressing compressed data. Unlike Zlib::Deflate, an instance of this class is not able to duplicate (clone, dup) itself.
Decompresses string
. Raises a Zlib::NeedDict exception if a preset dictionary is
needed for decompression.
This method is almost equivalent to the following code:
def inflate(string) zstream = Zlib::Inflate.new buf = zstream.inflate(string) zstream.finish zstream.close buf end
See also Zlib.deflate
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; }
Creates a new inflate stream for decompression. window_bits
sets the size of the history buffer and can have the following values:
Have inflate use the window size from the zlib header of the compressed stream.
Overrides the window size of the inflate header in the compressed stream. The window size must be greater than or equal to the window size of the compressed stream.
Add 32 to window_bits to enable zlib and gzip decoding with automatic header detection, or add 16 to decode only the gzip format (a Zlib::DataError will be raised for a non-gzip stream).
Enables raw deflate mode which will not generate a check value, and will not look for any check values for comparison at the end of the stream.
This is for use with other formats that use the deflate compressed data format such as zip which provide their own check values.
open "compressed.file" do |compressed_io| zi = Zlib::Inflate.new(Zlib::MAX_WBITS + 32) begin open "uncompressed.file", "w+" do |uncompressed_io| uncompressed_io << zi.inflate(compressed_io.read) end ensure zi.close end end
static VALUE rb_inflate_initialize(int argc, VALUE *argv, VALUE obj) { struct zstream *z; VALUE wbits; int err; rb_scan_args(argc, argv, "01", &wbits); TypedData_Get_Struct(obj, struct zstream, &zstream_data_type, z); err = inflateInit2(&z->stream, ARG_WBITS(wbits)); if (err != Z_OK) { raise_zlib_error(err, z->stream.msg); } ZSTREAM_READY(z); return obj; }
Same as IO.
static VALUE rb_inflate_addstr(VALUE obj, VALUE src) { struct zstream *z = get_zstream(obj); if (ZSTREAM_IS_FINISHED(z)) { if (!NIL_P(src)) { StringValue(src); zstream_append_buffer2(z, src); } } else { do_inflate(z, src); if (ZSTREAM_IS_FINISHED(z)) { zstream_passthrough_input(z); } } return obj; }
Provide the inflate stream with a dictionary that may be required in the future. Multiple dictionaries may be provided. The inflate stream will automatically choose the correct user-provided dictionary based on the stream's required dictionary.
static VALUE rb_inflate_add_dictionary(VALUE obj, VALUE dictionary) { VALUE dictionaries = rb_ivar_get(obj, id_dictionaries); VALUE checksum = do_checksum(1, &dictionary, adler32); rb_hash_aset(dictionaries, checksum, dictionary); return obj; }
Inputs deflate_string
into the inflate stream and returns the
output from the stream. Calling this method, both the input and the output
buffer of the stream are flushed. If string is nil
, this
method finishes the stream, just like Zlib::ZStream#finish.
If a block is given consecutive inflated chunks from the
deflate_string
are yielded to the block and nil
is returned.
Raises a Zlib::NeedDict exception if a preset dictionary is needed to decompress. Set the dictionary by #set_dictionary and then call this method again with an empty string to flush the stream:
inflater = Zlib::Inflate.new begin out = inflater.inflate compressed rescue Zlib::NeedDict # ensure the dictionary matches the stream's required dictionary raise unless inflater.adler == Zlib.adler32(dictionary) inflater.set_dictionary dictionary inflater.inflate '' end # ... inflater.close
See also ::new
static VALUE rb_inflate_inflate(VALUE obj, VALUE src) { struct zstream *z = get_zstream(obj); VALUE dst; if (ZSTREAM_IS_FINISHED(z)) { if (NIL_P(src)) { dst = zstream_detach_buffer(z); } else { StringValue(src); zstream_append_buffer2(z, src); dst = rb_str_new(0, 0); } } else { do_inflate(z, src); dst = zstream_detach_buffer(z); if (ZSTREAM_IS_FINISHED(z)) { zstream_passthrough_input(z); } } return dst; }
Sets the preset dictionary and returns string
. This method is
available just only after a Zlib::NeedDict
exception was raised. See zlib.h for details.
static VALUE rb_inflate_set_dictionary(VALUE obj, VALUE dic) { struct zstream *z = get_zstream(obj); VALUE src = dic; int err; StringValue(src); err = inflateSetDictionary(&z->stream, (Bytef*)RSTRING_PTR(src), RSTRING_LENINT(src)); if (err != Z_OK) { raise_zlib_error(err, z->stream.msg); } return dic; }
Inputs string
into the end of input buffer and skips data
until a full flush point can be found. If the point is found in the
buffer, this method flushes the buffer and returns false. Otherwise it
returns true
and the following data of full flush point is
preserved in the buffer.
static VALUE rb_inflate_sync(VALUE obj, VALUE src) { struct zstream *z = get_zstream(obj); StringValue(src); return zstream_sync(z, (Bytef*)RSTRING_PTR(src), RSTRING_LEN(src)); }
Quoted verbatim from original documentation:
What is this?
:)
static VALUE rb_inflate_sync_point_p(VALUE obj) { struct zstream *z = get_zstream(obj); int err; err = inflateSyncPoint(&z->stream); if (err == 1) { return Qtrue; } if (err != Z_OK) { raise_zlib_error(err, z->stream.msg); } return Qfalse; }