Crypto++  8.8
Free C++ class library of cryptographic schemes
files.cpp
1 // files.cpp - originally written and placed in the public domain by Wei Dai
2 
3 #include "pch.h"
4 
5 #ifndef CRYPTOPP_IMPORTS
6 
7 #include "files.h"
8 
9 #include <iostream>
10 #include <fstream>
11 #include <limits>
12 
13 ANONYMOUS_NAMESPACE_BEGIN
14 
15 /// \brief Disable badbit, failbit and eof exceptions
16 /// \sa https://github.com/weidai11/cryptopp/pull/968 and
17 /// https://www.cplusplus.com/reference/ios/ios/exceptions
18 class IosExceptionMask
19 {
20 public:
21  IosExceptionMask(std::istream& stream) : m_stream(stream) {
22  m_mask = m_stream.exceptions();
23  m_stream.exceptions(static_cast<std::ios::iostate>(0));
24  }
25 
26  IosExceptionMask(std::istream& stream, std::ios::iostate newMask) : m_stream(stream) {
27  m_mask = m_stream.exceptions();
28  m_stream.exceptions(newMask);
29  }
30 
31  ~IosExceptionMask() {
32  m_stream.exceptions(m_mask);
33  }
34 
35 private:
36  std::istream& m_stream;
37  std::ios::iostate m_mask;
38 };
39 
40 ANONYMOUS_NAMESPACE_END
41 
42 NAMESPACE_BEGIN(CryptoPP)
43 
44 #if defined(CRYPTOPP_DEBUG) && !defined(CRYPTOPP_DOXYGEN_PROCESSING)
45 void Files_TestInstantiations()
46 {
47  FileStore f0;
48  FileSource f1;
49  FileSink f2;
50 }
51 #endif
52 
53 void FileStore::StoreInitialize(const NameValuePairs &parameters)
54 {
55  m_waiting = false;
56  m_stream = NULLPTR;
57  m_file.release();
58 
59  const char *fileName = NULLPTR;
60 #if defined(CRYPTOPP_UNIX_AVAILABLE) || CRYPTOPP_MSC_VERSION >= 1400
61  const wchar_t *fileNameWide = NULLPTR;
62  if (!parameters.GetValue(Name::InputFileNameWide(), fileNameWide))
63 #endif
64  if (!parameters.GetValue(Name::InputFileName(), fileName))
65  {
66  parameters.GetValue(Name::InputStreamPointer(), m_stream);
67  return;
68  }
69 
70  std::ios::openmode binary = parameters.GetValueWithDefault(Name::InputBinaryMode(), true) ? std::ios::binary : std::ios::openmode(0);
71  m_file.reset(new std::ifstream);
72 #ifdef CRYPTOPP_UNIX_AVAILABLE
73  std::string narrowed;
74  if (fileNameWide)
75  fileName = (narrowed = StringNarrow(fileNameWide)).c_str();
76 #endif
77 #if CRYPTOPP_MSC_VERSION >= 1400
78  if (fileNameWide)
79  {
80  m_file->open(fileNameWide, std::ios::in | binary);
81  if (!*m_file)
82  throw OpenErr(StringNarrow(fileNameWide, false));
83  }
84 #endif
85  if (fileName)
86  {
87  m_file->open(fileName, std::ios::in | binary);
88  if (!*m_file)
89  throw OpenErr(fileName);
90  }
91  m_stream = m_file.get();
92 }
93 
95 {
96  if (!m_stream)
97  return 0;
98 
99  // Disable badbit, failbit and eof exceptions
100  IosExceptionMask guard(*m_stream);
101 
102  // Clear error bits due to seekg(). Also see
103  // https://github.com/weidai11/cryptopp/pull/968
104  std::streampos current = m_stream->tellg();
105  std::streampos end = m_stream->seekg(0, std::ios::end).tellg();
106  m_stream->clear();
107  m_stream->seekg(current);
108  m_stream->clear();
109 
110  // Return max for a non-seekable stream
111  // https://www.cplusplus.com/reference/istream/istream/tellg
112  if (end == static_cast<std::streampos>(-1))
113  return LWORD_MAX;
114 
115  return end-current;
116 }
117 
118 size_t FileStore::TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel, bool blocking)
119 {
120  if (!m_stream)
121  {
122  transferBytes = 0;
123  return 0;
124  }
125 
126  lword size=transferBytes;
127  transferBytes = 0;
128 
129  if (m_waiting)
130  goto output;
131 
132  size_t spaceSize, blockedBytes;
133  while (size && m_stream->good())
134  {
135  spaceSize = 1024;
136  m_space = HelpCreatePutSpace(target, channel, 1, UnsignedMin(size_t(SIZE_MAX), size), spaceSize);
137  m_stream->read((char *)m_space, (std::streamsize)STDMIN(size, (lword)spaceSize));
138  m_len = (size_t)m_stream->gcount();
139 
140 output:
141  blockedBytes = target.ChannelPutModifiable2(channel, m_space, m_len, 0, blocking);
142  m_waiting = blockedBytes > 0;
143  if (m_waiting)
144  return blockedBytes;
145  size -= m_len;
146  transferBytes += m_len;
147  }
148 
149  if (!m_stream->good() && !m_stream->eof())
150  throw ReadErr();
151 
152  return 0;
153 }
154 
155 size_t FileStore::CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end, const std::string &channel, bool blocking) const
156 {
157  if (!m_stream)
158  return 0;
159 
160  if (begin == 0 && end == 1)
161  {
162  int result = m_stream->peek();
163  if (result == std::char_traits<char>::eof())
164  return 0;
165  else
166  {
167  size_t blockedBytes = target.ChannelPut(channel, byte(result), blocking);
168  begin += 1-blockedBytes;
169  return blockedBytes;
170  }
171  }
172 
173  // TODO: figure out what happens on cin
174  std::streampos current = m_stream->tellg();
175  std::streampos endPosition = m_stream->seekg(0, std::ios::end).tellg();
176  std::streampos newPosition = current + static_cast<std::streamoff>(begin);
177 
178  if (newPosition >= endPosition)
179  {
180  m_stream->seekg(current);
181  return 0; // don't try to seek beyond the end of file
182  }
183  m_stream->seekg(newPosition);
184  try
185  {
186  CRYPTOPP_ASSERT(!m_waiting);
187  lword copyMax = end-begin;
188  size_t blockedBytes = const_cast<FileStore *>(this)->TransferTo2(target, copyMax, channel, blocking);
189  begin += copyMax;
190  if (blockedBytes)
191  {
192  const_cast<FileStore *>(this)->m_waiting = false;
193  return blockedBytes;
194  }
195  }
196  catch(...)
197  {
198  m_stream->clear();
199  m_stream->seekg(current);
200  throw;
201  }
202  m_stream->clear();
203  m_stream->seekg(current);
204 
205  return 0;
206 }
207 
208 lword FileStore::Skip(lword skipMax)
209 {
210  if (!m_stream)
211  return 0;
212 
213  lword oldPos = m_stream->tellg();
214  std::istream::off_type offset;
215  if (!SafeConvert(skipMax, offset))
216  throw InvalidArgument("FileStore: maximum seek offset exceeded");
217  m_stream->seekg(offset, std::ios::cur);
218  return (lword)m_stream->tellg() - oldPos;
219 }
220 
221 void FileSink::IsolatedInitialize(const NameValuePairs &parameters)
222 {
223  m_stream = NULLPTR;
224  m_file.release();
225 
226  const char *fileName = NULLPTR;
227 #if defined(CRYPTOPP_UNIX_AVAILABLE) || CRYPTOPP_MSC_VERSION >= 1400
228  const wchar_t *fileNameWide = NULLPTR;
229  if (!parameters.GetValue(Name::OutputFileNameWide(), fileNameWide))
230 #endif
231  if (!parameters.GetValue(Name::OutputFileName(), fileName))
232  {
233  parameters.GetValue(Name::OutputStreamPointer(), m_stream);
234  return;
235  }
236 
237  std::ios::openmode binary = parameters.GetValueWithDefault(Name::OutputBinaryMode(), true) ? std::ios::binary : std::ios::openmode(0);
238  m_file.reset(new std::ofstream);
239 #ifdef CRYPTOPP_UNIX_AVAILABLE
240  std::string narrowed;
241  if (fileNameWide)
242  fileName = (narrowed = StringNarrow(fileNameWide)).c_str();
243 #elif (CRYPTOPP_MSC_VERSION >= 1400)
244  if (fileNameWide)
245  {
246  m_file->open(fileNameWide, std::ios::out | std::ios::trunc | binary);
247  if (!*m_file)
248  throw OpenErr(StringNarrow(fileNameWide, false));
249  }
250 #endif
251  if (fileName)
252  {
253  m_file->open(fileName, std::ios::out | std::ios::trunc | binary);
254  if (!*m_file)
255  throw OpenErr(fileName);
256  }
257  m_stream = m_file.get();
258 }
259 
260 bool FileSink::IsolatedFlush(bool hardFlush, bool blocking)
261 {
262  CRYPTOPP_UNUSED(hardFlush), CRYPTOPP_UNUSED(blocking);
263  if (!m_stream)
264  throw Err("FileSink: output stream not opened");
265 
266  m_stream->flush();
267  if (!m_stream->good())
268  throw WriteErr();
269 
270  return false;
271 }
272 
273 size_t FileSink::Put2(const byte *inString, size_t length, int messageEnd, bool blocking)
274 {
275  CRYPTOPP_UNUSED(blocking);
276  if (!m_stream)
277  throw Err("FileSink: output stream not opened");
278 
279  while (length > 0)
280  {
281  std::streamsize size;
282  if (!SafeConvert(length, size))
283  size = ((std::numeric_limits<std::streamsize>::max)());
284  m_stream->write((const char *)inString, size);
285  inString += size;
286  length -= (size_t)size;
287  }
288 
289  if (messageEnd)
290  m_stream->flush();
291 
292  if (!m_stream->good())
293  throw WriteErr();
294 
295  return 0;
296 }
297 
298 NAMESPACE_END
299 
300 #endif
Interface for buffered transformations.
Definition: cryptlib.h:1657
virtual size_t ChannelPutModifiable2(const std::string &channel, byte *inString, size_t length, int messageEnd, bool blocking)
Input multiple bytes that may be modified by callee on a channel.
size_t ChannelPut(const std::string &channel, byte inByte, bool blocking=true)
Input a byte for processing on a channel.
Definition: cryptlib.h:2199
Implementation of Store interface.
Definition: files.h:131
size_t Put2(const byte *inString, size_t length, int messageEnd, bool blocking)
Input multiple bytes for processing.
void IsolatedInitialize(const NameValuePairs &parameters)
Initialize or reinitialize this object, without signal propagation.
bool IsolatedFlush(bool hardFlush, bool blocking)
Flushes data buffered by this object, without signal propagation.
Implementation of Store interface.
Definition: files.h:87
Implementation of Store interface.
Definition: files.h:23
size_t TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true)
Transfer bytes from this object to another BufferedTransformation.
lword Skip(lword skipMax=ULONG_MAX)
Discard skipMax bytes from the output buffer.
lword MaxRetrievable() const
Provides the number of bytes ready for retrieval.
size_t CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end=LWORD_MAX, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true) const
Copy bytes from this object to another BufferedTransformation.
An invalid argument was detected.
Definition: cryptlib.h:208
Interface for retrieving values given their names.
Definition: cryptlib.h:327
T GetValueWithDefault(const char *name, T defaultValue) const
Get a named value.
Definition: cryptlib.h:397
bool GetValue(const char *name, T &value) const
Get a named value.
Definition: cryptlib.h:384
const lword LWORD_MAX
Large word type max value.
Definition: config_int.h:174
word64 lword
Large word type.
Definition: config_int.h:168
Classes providing file-based library services.
#define SIZE_MAX
The maximum value of a machine word.
Definition: misc.h:120
bool SafeConvert(T1 from, T2 &to)
Perform a conversion from from to to.
Definition: misc.h:718
std::string StringNarrow(const wchar_t *str, bool throwOnError=true)
Converts a wide character C-string to a multibyte string.
const T & STDMIN(const T &a, const T &b)
Replacement function for std::min.
Definition: misc.h:657
const T1 UnsignedMin(const T1 &a, const T2 &b)
Safe comparison of values that could be negative and incorrectly promoted.
Definition: misc.h:695
Crypto++ library namespace.
const char * InputBinaryMode()
bool
Definition: argnames.h:61
const char * OutputBinaryMode()
bool
Definition: argnames.h:65
const char * InputStreamPointer()
std::istream *
Definition: argnames.h:60
const char * OutputFileName()
const char *
Definition: argnames.h:62
const char * InputFileNameWide()
const wchar_t *
Definition: argnames.h:59
const char * OutputFileNameWide()
const wchar_t *
Definition: argnames.h:63
const char * OutputStreamPointer()
std::ostream *
Definition: argnames.h:64
const char * InputFileName()
const char *
Definition: argnames.h:58
Precompiled header file.
byte * HelpCreatePutSpace(BufferedTransformation &target, const std::string &channel, size_t minSize, size_t desiredSize, size_t &bufferSize)
Create a working space in a BufferedTransformation.
Definition: filters.h:187
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:68