Class: Zlib::GzipReader
- Includes:
- Enumerable
- Defined in:
- zlib.c
Overview
Zlib::GzipReader is the class for reading a gzipped file. GzipReader should be used an IO, or -IO-lie, object.
Zlib::GzipReader.open('hoge.gz') {|gz|
print gz.read
}
File.open('hoge.gz') do |f|
gz = Zlib::GzipReader.new(f)
print gz.read
gz.close
end
Method Catalogue
The following methods in Zlib::GzipReader are just like their counterparts in IO, but they raise Zlib::Error or Zlib::GzipFile::Error exception if an error was found in the gzip file.
-
#each
-
#each_line
-
#each_byte
-
#gets
-
#getc
-
#lineno
-
#lineno=
-
#read
-
#readchar
-
#readline
-
#readlines
-
#ungetc
Be careful of the footer of the gzip file. A gzip file has the checksum of pre-compressed data in its footer. GzipReader checks all uncompressed data against that checksum at the following cases, and if it fails, raises Zlib::GzipFile::NoFooter
, Zlib::GzipFile::CRCError
, or Zlib::GzipFile::LengthError
exception.
-
When an reading request is received beyond the end of file (the end of compressed data). That is, when Zlib::GzipReader#read, Zlib::GzipReader#gets, or some other methods for reading returns nil.
-
When Zlib::GzipFile#close method is called after the object reaches the end of file.
-
When Zlib::GzipReader#unused method is called after the object reaches the end of file.
The rest of the methods are adequately described in their own documentation.
Class Method Summary collapse
-
.open ⇒ Object
call-seq: Zlib::GzipReader.open(filename) {|gz| ... }.
Instance Method Summary collapse
-
#bytes ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each_byte ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each_char ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each_line ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#eof ⇒ Object
Returns
true
orfalse
whether the stream has reached the end. -
#eof? ⇒ Boolean
Returns
true
orfalse
whether the stream has reached the end. -
#getbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#getc ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#gets ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#initialize ⇒ Object
constructor
call-seq: Zlib::GzipReader.new(io).
-
#lineno ⇒ Object
The line number of the last row read from this file.
-
#lineno= ⇒ Object
Specify line number of the last row read from this file.
-
#lines ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#pos ⇒ Object
Total number of output bytes output so far.
-
#read ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#readbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#readchar ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#readline ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#readlines ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#readpartial ⇒ Object
call-seq: gzipreader.readpartial(maxlen [, outbuf]) => string, outbuf.
-
#rewind ⇒ Object
Resets the position of the file pointer to the point created the GzipReader object.
-
#tell ⇒ Object
Total number of output bytes output so far.
-
#ungetbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#ungetc ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#unused ⇒ Object
Returns the rest of the data which had read for parsing gzip format, or
nil
if the whole gzip file is not parsed yet.
Methods inherited from GzipFile
#close, #closed?, #comment, #crc, #finish, #level, #mtime, #orig_name, #os_code, #sync, #sync=, #to_io, wrap
Constructor Details
#initialize ⇒ Object
call-seq: Zlib::GzipReader.new(io)
Creates a GzipReader object associated with io
. The GzipReader object reads gzipped data from io
, and parses/decompresses them. At least, io
must have a read
method that behaves same as the read
method in IO class.
If the gzip file header is incorrect, raises an Zlib::GzipFile::Error exception.
3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 |
# File 'zlib.c', line 3406
static VALUE
rb_gzreader_initialize(int argc, VALUE *argv, VALUE obj)
{
VALUE io, opt = Qnil;
struct gzfile *gz;
int err;
Data_Get_Struct(obj, struct gzfile, gz);
rb_scan_args(argc, argv, "1:", &io, &opt);
/* this is undocumented feature of zlib */
err = inflateInit2(&gz->z.stream, -MAX_WBITS);
if (err != Z_OK) {
raise_zlib_error(err, gz->z.stream.msg);
}
gz->io = io;
ZSTREAM_READY(&gz->z);
gzfile_read_header(gz);
rb_gzfile_ecopts(gz, opt);
if (rb_respond_to(io, id_path)) {
gz->path = rb_funcall(gz->io, id_path, 0);
rb_define_singleton_method(obj, "path", rb_gzfile_path, 0);
}
return obj;
}
|
Class Method Details
.open ⇒ Object
call-seq: Zlib::GzipReader.open(filename) {|gz| ... }
Opens a file specified by filename
as a gzipped file, and returns a GzipReader object associated with that file. Further details of this method are in Zlib::GzipReader.new and ZLib::GzipFile.wrap.
3388 3389 3390 3391 3392 |
# File 'zlib.c', line 3388
static VALUE
rb_gzreader_s_open(int argc, VALUE *argv, VALUE klass)
{
return gzfile_s_open(argc, argv, klass, "rb");
}
|
Instance Method Details
#bytes ⇒ Object
See Zlib::GzipReader documentation for a description.
3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 |
# File 'zlib.c', line 3602
static VALUE
rb_gzreader_each_byte(VALUE obj)
{
VALUE c;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(c = rb_gzreader_getbyte(obj))) {
rb_yield(c);
}
return Qnil;
}
|
#each ⇒ Object
See Zlib::GzipReader documentation for a description.
3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 |
# File 'zlib.c', line 3868
static VALUE
rb_gzreader_each(int argc, VALUE *argv, VALUE obj)
{
VALUE str;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_yield(str);
}
return obj;
}
|
#each_byte ⇒ Object
See Zlib::GzipReader documentation for a description.
3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 |
# File 'zlib.c', line 3602
static VALUE
rb_gzreader_each_byte(VALUE obj)
{
VALUE c;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(c = rb_gzreader_getbyte(obj))) {
rb_yield(c);
}
return Qnil;
}
|
#each_char ⇒ Object
See Zlib::GzipReader documentation for a description.
3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 |
# File 'zlib.c', line 3584
static VALUE
rb_gzreader_each_char(VALUE obj)
{
VALUE c;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(c = rb_gzreader_getc(obj))) {
rb_yield(c);
}
return Qnil;
}
|
#each_line ⇒ Object
See Zlib::GzipReader documentation for a description.
3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 |
# File 'zlib.c', line 3868
static VALUE
rb_gzreader_each(int argc, VALUE *argv, VALUE obj)
{
VALUE str;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_yield(str);
}
return obj;
}
|
#eof ⇒ Object
Returns true
or false
whether the stream has reached the end.
3046 3047 3048 3049 3050 3051 |
# File 'zlib.c', line 3046
static VALUE
rb_gzfile_eof_p(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
return GZFILE_IS_FINISHED(gz) ? Qtrue : Qfalse;
}
|
#eof? ⇒ Boolean
Returns true
or false
whether the stream has reached the end.
3046 3047 3048 3049 3050 3051 |
# File 'zlib.c', line 3046
static VALUE
rb_gzfile_eof_p(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
return GZFILE_IS_FINISHED(gz) ? Qtrue : Qfalse;
}
|
#getbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 |
# File 'zlib.c', line 3550
static VALUE
rb_gzreader_getbyte(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
VALUE dst;
dst = gzfile_read(gz, 1);
if (!NIL_P(dst)) {
dst = INT2FIX((unsigned int)(RSTRING_PTR(dst)[0]) & 0xff);
}
return dst;
}
|
#getc ⇒ Object
See Zlib::GzipReader documentation for a description.
3521 3522 3523 3524 3525 3526 3527 |
# File 'zlib.c', line 3521
static VALUE
rb_gzreader_getc(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
return gzfile_getc(gz);
}
|
#gets ⇒ Object
See Zlib::GzipReader documentation for a description.
3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 |
# File 'zlib.c', line 3836
static VALUE
rb_gzreader_gets(int argc, VALUE *argv, VALUE obj)
{
VALUE dst;
dst = gzreader_gets(argc, argv, obj);
if (!NIL_P(dst)) {
rb_lastline_set(dst);
}
return dst;
}
|
#lineno ⇒ Object
The line number of the last row read from this file.
2899 2900 2901 2902 2903 |
# File 'zlib.c', line 2899
static VALUE
rb_gzfile_lineno(VALUE obj)
{
return INT2NUM(get_gzfile(obj)->lineno);
}
|
#lineno= ⇒ Object
Specify line number of the last row read from this file.
2910 2911 2912 2913 2914 2915 2916 |
# File 'zlib.c', line 2910
static VALUE
rb_gzfile_set_lineno(VALUE obj, VALUE lineno)
{
struct gzfile *gz = get_gzfile(obj);
gz->lineno = NUM2INT(lineno);
return lineno;
}
|
#lines ⇒ Object
See Zlib::GzipReader documentation for a description.
3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 |
# File 'zlib.c', line 3868
static VALUE
rb_gzreader_each(int argc, VALUE *argv, VALUE obj)
{
VALUE str;
RETURN_ENUMERATOR(obj, 0, 0);
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_yield(str);
}
return obj;
}
|
#pos ⇒ Object
Total number of output bytes output so far.
3104 3105 3106 3107 3108 3109 |
# File 'zlib.c', line 3104
static VALUE
rb_gzfile_total_out(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
return rb_uint2inum(gz->z.stream.total_out - gz->z.buf_filled);
}
|
#read ⇒ Object
See Zlib::GzipReader documentation for a description.
3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 |
# File 'zlib.c', line 3467
static VALUE
rb_gzreader_read(int argc, VALUE *argv, VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
VALUE vlen;
long len;
rb_scan_args(argc, argv, "01", &vlen);
if (NIL_P(vlen)) {
return gzfile_read_all(gz);
}
len = NUM2INT(vlen);
if (len < 0) {
rb_raise(rb_eArgError, "negative length %ld given", len);
}
return gzfile_read(gz, len);
}
|
#readbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 |
# File 'zlib.c', line 3568
static VALUE
rb_gzreader_readbyte(VALUE obj)
{
VALUE dst;
dst = rb_gzreader_getbyte(obj);
if (NIL_P(dst)) {
rb_raise(rb_eEOFError, "end of file reached");
}
return dst;
}
|
#readchar ⇒ Object
See Zlib::GzipReader documentation for a description.
3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 |
# File 'zlib.c', line 3534
static VALUE
rb_gzreader_readchar(VALUE obj)
{
VALUE dst;
dst = rb_gzreader_getc(obj);
if (NIL_P(dst)) {
rb_raise(rb_eEOFError, "end of file reached");
}
return dst;
}
|
#readline ⇒ Object
See Zlib::GzipReader documentation for a description.
3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 |
# File 'zlib.c', line 3852
static VALUE
rb_gzreader_readline(int argc, VALUE *argv, VALUE obj)
{
VALUE dst;
dst = rb_gzreader_gets(argc, argv, obj);
if (NIL_P(dst)) {
rb_raise(rb_eEOFError, "end of file reached");
}
return dst;
}
|
#readlines ⇒ Object
See Zlib::GzipReader documentation for a description.
3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 |
# File 'zlib.c', line 3886
static VALUE
rb_gzreader_readlines(int argc, VALUE *argv, VALUE obj)
{
VALUE str, dst;
dst = rb_ary_new();
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_ary_push(dst, str);
}
return dst;
}
|
#readpartial ⇒ Object
call-seq:
gzipreader.readpartial(maxlen [, outbuf]) => string, outbuf
Reads at most <i>maxlen</i> bytes from the gziped stream but
it blocks only if <em>gzipreader</em> has no data immediately available.
If the optional <i>outbuf</i> argument is present,
it must reference a String, which will receive the data.
It raises <code>EOFError</code> on end of file.
3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 |
# File 'zlib.c', line 3498
static VALUE
rb_gzreader_readpartial(int argc, VALUE *argv, VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
VALUE vlen, outbuf;
long len;
rb_scan_args(argc, argv, "11", &vlen, &outbuf);
len = NUM2INT(vlen);
if (len < 0) {
rb_raise(rb_eArgError, "negative length %ld given", len);
}
if (!NIL_P(outbuf))
Check_Type(outbuf, T_STRING);
return gzfile_readpartial(gz, len, outbuf);
}
|
#rewind ⇒ Object
Resets the position of the file pointer to the point created the GzipReader object. The associated IO object needs to respond to the seek
method.
3440 3441 3442 3443 3444 3445 3446 |
# File 'zlib.c', line 3440
static VALUE
rb_gzreader_rewind(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
gzfile_reader_rewind(gz);
return INT2FIX(0);
}
|
#tell ⇒ Object
Total number of output bytes output so far.
3104 3105 3106 3107 3108 3109 |
# File 'zlib.c', line 3104
static VALUE
rb_gzfile_total_out(VALUE obj)
{
struct gzfile *gz = get_gzfile(obj);
return rb_uint2inum(gz->z.stream.total_out - gz->z.buf_filled);
}
|
#ungetbyte ⇒ Object
See Zlib::GzipReader documentation for a description.
3641 3642 3643 3644 3645 3646 3647 |
# File 'zlib.c', line 3641
static VALUE
rb_gzreader_ungetbyte(VALUE obj, VALUE ch)
{
struct gzfile *gz = get_gzfile(obj);
gzfile_ungetbyte(gz, NUM2CHR(ch));
return Qnil;
}
|
#ungetc ⇒ Object
See Zlib::GzipReader documentation for a description.
3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 |
# File 'zlib.c', line 3620
static VALUE
rb_gzreader_ungetc(VALUE obj, VALUE s)
{
struct gzfile *gz;
if (FIXNUM_P(s))
return rb_gzreader_ungetbyte(obj, s);
gz = get_gzfile(obj);
StringValue(s);
if (gz->enc2 && gz->enc2 != rb_ascii8bit_encoding()) {
s = rb_str_conv_enc(s, rb_enc_get(s), gz->enc2);
}
gzfile_ungets(gz, (const Bytef*)RSTRING_PTR(s), RSTRING_LEN(s));
return Qnil;
}
|
#unused ⇒ Object
Returns the rest of the data which had read for parsing gzip format, or nil
if the whole gzip file is not parsed yet.
3454 3455 3456 3457 3458 3459 3460 |
# File 'zlib.c', line 3454
static VALUE
rb_gzreader_unused(VALUE obj)
{
struct gzfile *gz;
Data_Get_Struct(obj, struct gzfile, gz);
return gzfile_reader_get_unused(gz);
}
|