1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
// ============================================================================
// gzstream, C++ iostream classes wrapping the zlib compression library.
// Copyright (C) 2001 Deepak Bandyopadhyay, Lutz Kettner
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// ============================================================================
//
// File : gzstream.C
// Revision : $Revision: 1.7 $
// Revision_date : $Date: 2003/01/08 14:41:27 $
// Author(s) : Deepak Bandyopadhyay, Lutz Kettner
//
// Standard streambuf implementation following Nicolai Josuttis, "The
// Standard C++ Library".
// ============================================================================
#include <gzstream.h>
#include <iostream>
#include <cstring> // for memcpy
#include <stdexcept>
#ifdef GZSTREAM_NAMESPACE
namespace GZSTREAM_NAMESPACE {
#endif
// ----------------------------------------------------------------------------
// Internal classes to implement gzstream. See header file for user classes.
// ----------------------------------------------------------------------------
// --------------------------------------
// class gzstreambuf:
// --------------------------------------
gzstreambuf* gzstreambuf::open( const char* name, int open_mode) {
if ( is_open())
return (gzstreambuf*)0;
mode = open_mode;
// no append nor read/write mode
if ((mode & std::ios::ate) || (mode & std::ios::app)
|| ((mode & std::ios::in) && (mode & std::ios::out)))
return (gzstreambuf*)0;
char fmode[10];
char* fmodeptr = fmode;
if ( mode & std::ios::in)
*fmodeptr++ = 'r';
else if ( mode & std::ios::out)
*fmodeptr++ = 'w';
*fmodeptr++ = 'b';
*fmodeptr = '\0';
file = gzopen( name, fmode);
if (!file) handle_gzerror();
if (file == 0)
return (gzstreambuf*)0;
opened = 1;
return this;
}
gzstreambuf * gzstreambuf::close() {
if ( is_open()) {
sync();
opened = 0;
if ( gzclose( file) == Z_OK)
return this;
else
handle_gzerror();
}
return (gzstreambuf*)0;
}
void gzstreambuf::handle_gzerror() {
int errnum;
const char *errmsg=gzerror(file,&errnum);
if (errnum==Z_DATA_ERROR) errmsg="CRC error reading gzip";
throw std::runtime_error(std::string("gzstreambuf error: ")+errmsg);
}
int gzstreambuf::underflow() { // used for input buffer only
if ( gptr() && ( gptr() < egptr()))
return * reinterpret_cast<unsigned char *>( gptr());
if ( ! (mode & std::ios::in) || ! opened)
return EOF;
// Josuttis' implementation of inbuf
int n_putback = gptr() - eback();
if ( n_putback > 4)
n_putback = 4;
std::memcpy( buffer + (4 - n_putback), gptr() - n_putback, n_putback);
int num = gzread( file, buffer+4, bufferSize-4);
if (num <= 0) // ERROR or EOF
{
if (gzeof(file))
return EOF;
handle_gzerror();
}
// reset buffer pointers
setg( buffer + (4 - n_putback), // beginning of putback area
buffer + 4, // read position
buffer + 4 + num); // end of buffer
// return next character
return * reinterpret_cast<unsigned char *>( gptr());
}
int gzstreambuf::flush_buffer() {
// Separate the writing of the buffer from overflow() and
// sync() operation.
int w = pptr() - pbase();
if ( gzwrite( file, pbase(), w) != w)
handle_gzerror();
pbump( -w);
return w;
}
int gzstreambuf::overflow( int c) { // used for output buffer only
if ( ! ( mode & std::ios::out) || ! opened)
return EOF;
if (c != EOF) {
*pptr() = c;
pbump(1);
}
if ( flush_buffer() == EOF)
return EOF;
return c;
}
int gzstreambuf::sync() {
// Changed to use flush_buffer() instead of overflow( EOF)
// which caused improper behavior with std::endl and flush(),
// bug reported by Vincent Ricard.
if ( pptr() && pptr() > pbase()) {
if ( flush_buffer() == EOF)
return -1;
}
return 0;
}
// --------------------------------------
// class gzstreambase:
// --------------------------------------
gzstreambase::gzstreambase( const char* name, int mode) {
init( &buf);
open( name, mode);
}
gzstreambase::~gzstreambase() {
buf.close();
}
void gzstreambase::open( const char* name, int open_mode) {
if ( ! buf.open( name, open_mode))
clear( rdstate() | std::ios::badbit);
}
void gzstreambase::close() {
if ( buf.is_open())
if ( ! buf.close())
clear( rdstate() | std::ios::badbit);
}
#ifdef GZSTREAM_NAMESPACE
} // namespace GZSTREAM_NAMESPACE
#endif
// ============================================================================
// EOF //
|
