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
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
|
/******************************************************************************
*
* Purpose: Implementation of a stdio based IO layer.
*
******************************************************************************
* Copyright (c) 2009
* PCI Geomatics, 50 West Wilmot Street, Richmond Hill, Ont, Canada
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
****************************************************************************/
#include "pcidsk_io.h"
#include "pcidsk_exception.h"
#include <cstdio>
#include <cstring>
#include <string>
#include <cerrno>
using namespace PCIDSK;
class StdioIOInterface : public IOInterfaces
{
virtual void *Open( std::string filename, std::string access ) const;
virtual uint64 Seek( void *io_handle, uint64 offset, int whence ) const;
virtual uint64 Tell( void *io_handle ) const;
virtual uint64 Read( void *buffer, uint64 size, uint64 nmemb, void *io_hanle ) const;
virtual uint64 Write( const void *buffer, uint64 size, uint64 nmemb, void *io_handle ) const;
virtual int Eof( void *io_handle ) const;
virtual int Flush( void *io_handle ) const;
virtual int Close( void *io_handle ) const;
const char *LastError() const;
};
typedef struct {
FILE *fp;
uint64 offset;
bool last_op_write;
} FileInfo;
/************************************************************************/
/* GetDefaultIOInterfaces() */
/************************************************************************/
/**
* Fetch default IO interfaces.
*
* Returns the default IO interfaces implemented in the PCIDSK library.
* These are suitable for use in a PCIDSK::PCIDSKInterfaces object.
*
* @return pointer to internal IO interfaces class.
*/
const IOInterfaces *PCIDSK::GetDefaultIOInterfaces()
{
static StdioIOInterface singleton_stdio_interface;
return &singleton_stdio_interface;
}
/************************************************************************/
/* Open() */
/************************************************************************/
void *
StdioIOInterface::Open( std::string filename, std::string access ) const
{
std::string adjusted_access = access;
adjusted_access += "b";
FILE *fp = fopen( filename.c_str(), adjusted_access.c_str() );
if( fp == NULL )
ThrowPCIDSKException( "Failed to open %s: %s",
filename.c_str(), LastError() );
FileInfo *fi = new FileInfo();
fi->fp = fp;
fi->offset = 0;
fi->last_op_write = false;
return fi;
}
/************************************************************************/
/* Seek() */
/************************************************************************/
uint64
StdioIOInterface::Seek( void *io_handle, uint64 offset, int whence ) const
{
FileInfo *fi = (FileInfo *) io_handle;
// seeks that do nothing are still surprisingly expensive with MSVCRT.
// try and short circuit if possible.
if( whence == SEEK_SET && offset == fi->offset )
return 0;
uint64 result = fseek( fi->fp, offset, whence );
if( result == (uint64) -1 )
ThrowPCIDSKException( "Seek(%d,%d): %s",
(int) offset, whence,
LastError() );
if( whence == SEEK_SET )
fi->offset = offset;
else if( whence == SEEK_END )
fi->offset = ftell( fi->fp );
else if( whence == SEEK_CUR )
fi->offset += offset;
fi->last_op_write = false;
return result;
}
/************************************************************************/
/* Tell() */
/************************************************************************/
uint64 StdioIOInterface::Tell( void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
return ftell( fi->fp );
}
/************************************************************************/
/* Read() */
/************************************************************************/
uint64 StdioIOInterface::Read( void *buffer, uint64 size, uint64 nmemb,
void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
errno = 0;
/* -------------------------------------------------------------------- */
/* If a fwrite() is followed by an fread(), the POSIX rules are */
/* that some of the write may still be buffered and lost. We */
/* are required to do a seek between to force flushing. So we */
/* keep careful track of what happened last to know if we */
/* skipped a flushing seek that we may need to do now. */
/* -------------------------------------------------------------------- */
if( fi->last_op_write )
fseek( fi->fp, fi->offset, SEEK_SET );
/* -------------------------------------------------------------------- */
/* Do the read. */
/* -------------------------------------------------------------------- */
uint64 result = fread( buffer, size, nmemb, fi->fp );
if( errno != 0 && result == 0 && nmemb != 0 )
ThrowPCIDSKException( "Read(%d): %s",
(int) size * nmemb,
LastError() );
fi->offset += size*result;
fi->last_op_write = false;
return result;
}
/************************************************************************/
/* Write() */
/************************************************************************/
uint64 StdioIOInterface::Write( const void *buffer, uint64 size, uint64 nmemb,
void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
errno = 0;
uint64 result = fwrite( buffer, size, nmemb, fi->fp );
if( errno != 0 && result == 0 && nmemb != 0 )
ThrowPCIDSKException( "Write(%d): %s",
(int) size * nmemb,
LastError() );
fi->offset += size*result;
fi->last_op_write = true;
return result;
}
/************************************************************************/
/* Eof() */
/************************************************************************/
int StdioIOInterface::Eof( void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
return feof( fi->fp );
}
/************************************************************************/
/* Flush() */
/************************************************************************/
int StdioIOInterface::Flush( void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
return fflush( fi->fp );
}
/************************************************************************/
/* Close() */
/************************************************************************/
int StdioIOInterface::Close( void *io_handle ) const
{
FileInfo *fi = (FileInfo *) io_handle;
int result = fclose( fi->fp );
delete fi;
return result;
}
/************************************************************************/
/* LastError() */
/* */
/* Return a string representation of the last error. */
/************************************************************************/
const char *StdioIOInterface::LastError() const
{
return strerror( errno );
}
|
