libopenraw
memstream.cpp
1 /*
2  * libopenraw - memstream.cpp
3  *
4  * Copyright (C) 2007-2017 Hubert Figuière
5  *
6  * This library is free software: you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public License
8  * as published by the Free Software Foundation, either version 3 of
9  * the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library. If not, see
18  * <http://www.gnu.org/licenses/>.
19  */
20 
21 
22 #include <string.h>
23 #include <stdio.h>
24 
25 #include <libopenraw/consts.h>
26 #include <libopenraw/debug.h>
27 
28 #include "memstream.hpp"
29 #include "trace.hpp"
30 
31 using namespace Debug;
32 
33 namespace OpenRaw {
34 namespace IO {
35 
36 MemStream::MemStream(void *ptr, size_t s)
37  : Stream(""),
38  m_ptr(ptr),
39  m_size(s),
40  m_current(nullptr)
41 {
42 }
43 
44 or_error MemStream::open()
45 {
46  m_current = (unsigned char *)m_ptr;
47  return OR_ERROR_NONE;
48 }
49 
50 
51 int MemStream::close()
52 {
53  m_current = NULL;
54  return 0;
55 }
56 
57 int MemStream::seek(off_t offset, int whence)
58 {
59  int newpos = 0;
60 // LOGDBG1("MemStream::seek %ld bytes - whence = %d", offset, whence);
61  // TODO check bounds
62  if (m_current == nullptr) {
63  // TODO set error code
64  return -1;
65  }
66  switch(whence)
67  {
68  case SEEK_SET:
69  m_current = (unsigned char*)m_ptr + offset;
70  newpos = offset;
71  break;
72  case SEEK_END:
73  m_current = (unsigned char*)m_ptr + m_size + offset;
74  newpos = m_size + offset;
75  break;
76  case SEEK_CUR:
77  m_current += offset;
78  newpos = (m_current - (unsigned char*)m_ptr);
79  break;
80  default:
81  return -1;
82  break;
83  }
84  return newpos;
85 }
86 
87 
88 int MemStream::read(void *buf, size_t count)
89 {
90  if((m_current == nullptr) || (m_ptr == nullptr)) {
91  LOGDBG1("MemStream::failed\n");
92  return -1;
93  }
94 
95  unsigned char * end = (unsigned char*)m_ptr + m_size;
96  if((off_t)count > (end - m_current)) {
97  count = end - m_current;
98  // TODO set EOF
99  }
100  memcpy(buf, m_current, count);
101  m_current += count;
102  return count;
103 }
104 
105 
106 off_t MemStream::filesize()
107 {
108  return m_size;
109 }
110 
111 }
112 }
113 /*
114  Local Variables:
115  mode:c++
116  c-file-style:"stroustrup"
117  c-file-offsets:((innamespace . 0))
118  tab-width:2
119  c-basic-offset:2
120  indent-tabs-mode:nil
121  fill-column:80
122  End:
123 */
CIFF is the container for CRW files. It is an attempt from Canon to make this a standard. I guess it failed.
Definition: arwfile.cpp:30
Definition: trace.cpp:30