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
# TODO: test these. Are they equivalent? Can GzipReader.new take a
# block?
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
-
.Zlib::GzipReader.open(filename) {|gz| ... } ⇒ Object
Opens a file specified by
filename
as a gzipped file, and returns a GzipReader object associated with that file.
Instance Method Summary collapse
-
#each ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each_byte ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#each_line ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#eof ⇒ Object
???.
-
#eof? ⇒ Object
???.
-
#getc ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#gets ⇒ Object
See Zlib::GzipReader documentation for a description.
-
#Zlib::GzipReader.new(io) ⇒ Object
constructor
Creates a GzipReader object associated with
io
. -
#lineno ⇒ Object
???.
-
#lineno= ⇒ Object
???.
-
#pos ⇒ Object
???.
-
#read ⇒ 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.
-
#rewind ⇒ Object
Resets the position of the file pointer to the point created the GzipReader object.
-
#tell ⇒ Object
???.
-
#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
#Zlib::GzipReader.new(io) ⇒ Object
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.
|
# File 'zlib.c'
/*
* 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.
*/
static VALUE
rb_gzreader_initialize(obj, io)
VALUE obj, io;
{
struct gzfile *gz;
int err;
Data_Get_Struct(obj, struct gzfile, gz);
/* 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);
return obj;
}
|
Class Method Details
.Zlib::GzipReader.open(filename) {|gz| ... } ⇒ Object
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::GzipReader.wrap.
|
# File 'zlib.c'
/*
* 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::GzipReader.wrap.
*/
static VALUE
rb_gzreader_s_open(argc, argv, klass)
int argc;
VALUE *argv;
VALUE klass;
{
return gzfile_s_open(argc, argv, klass, "rb");
}
|
Instance Method Details
#each ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_each(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE str;
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_yield(str);
}
return obj;
}
|
#each_byte ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_each_byte(obj)
VALUE obj;
{
VALUE c;
while (!NIL_P(c = rb_gzreader_getc(obj))) {
rb_yield(c);
}
return Qnil;
}
|
#each_line ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_each(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE str;
while (!NIL_P(str = gzreader_gets(argc, argv, obj))) {
rb_yield(str);
}
return obj;
}
|
#eof ⇒ Object
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_eof_p(obj)
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
return GZFILE_IS_FINISHED(gz) ? Qtrue : Qfalse;
}
|
#eof? ⇒ Object
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_eof_p(obj)
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
return GZFILE_IS_FINISHED(gz) ? Qtrue : Qfalse;
}
|
#getc ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_getc(obj)
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
VALUE dst;
dst = gzfile_read(gz, 1);
if (!NIL_P(dst)) {
dst = INT2FIX((unsigned int)(RSTRING(dst)->ptr[0]) & 0xff);
}
return dst;
}
|
#gets ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_gets(argc, argv, obj)
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
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_lineno(obj)
VALUE obj;
{
return INT2NUM(get_gzfile(obj)->lineno);
}
|
#lineno= ⇒ Object
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_set_lineno(obj, lineno)
VALUE obj, lineno;
{
struct gzfile *gz = get_gzfile(obj);
gz->lineno = NUM2INT(lineno);
return lineno;
}
|
#pos ⇒ Object
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_total_out(obj)
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.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_read(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
VALUE vlen;
int 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 %d given", len);
}
return gzfile_read(gz, len);
}
|
#readchar ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_readchar(obj)
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.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_readline(argc, argv, obj)
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.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_readlines(argc, argv, obj)
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;
}
|
#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.
|
# File 'zlib.c'
/*
* 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.
*/
static VALUE
rb_gzreader_rewind(obj)
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
gzfile_reader_rewind(gz);
return INT2FIX(0);
}
|
#tell ⇒ Object
???
|
# File 'zlib.c'
/*
* ???
*/
static VALUE
rb_gzfile_total_out(obj)
VALUE obj;
{
struct gzfile *gz = get_gzfile(obj);
return rb_uint2inum(gz->z.stream.total_out - gz->z.buf_filled);
}
|
#ungetc ⇒ Object
See Zlib::GzipReader documentation for a description.
|
# File 'zlib.c'
/*
* See Zlib::GzipReader documentation for a description.
*/
static VALUE
rb_gzreader_ungetc(obj, ch)
VALUE obj, ch;
{
struct gzfile *gz = get_gzfile(obj);
gzfile_ungetc(gz, NUM2CHR(ch));
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.
|
# File 'zlib.c'
/*
* Returns the rest of the data which had read for parsing gzip format, or
* +nil+ if the whole gzip file is not parsed yet.
*/
static VALUE
rb_gzreader_unused(obj)
VALUE obj;
{
struct gzfile *gz;
Data_Get_Struct(obj, struct gzfile, gz);
return gzfile_reader_get_unused(gz);
}
|