HDK
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Pages
ImfIO.h
Go to the documentation of this file.
1 ///////////////////////////////////////////////////////////////////////////
2 //
3 // Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
4 // Digital Ltd. LLC
5 //
6 // All rights reserved.
7 //
8 // Redistribution and use in source and binary forms, with or without
9 // modification, are permitted provided that the following conditions are
10 // met:
11 // * Redistributions of source code must retain the above copyright
12 // notice, this list of conditions and the following disclaimer.
13 // * Redistributions in binary form must reproduce the above
14 // copyright notice, this list of conditions and the following disclaimer
15 // in the documentation and/or other materials provided with the
16 // distribution.
17 // * Neither the name of Industrial Light & Magic nor the names of
18 // its contributors may be used to endorse or promote products derived
19 // from this software without specific prior written permission.
20 //
21 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 //
33 ///////////////////////////////////////////////////////////////////////////
34 
35 
36 #ifndef INCLUDED_IMF_IO_H
37 #define INCLUDED_IMF_IO_H
38 
39 //-----------------------------------------------------------------------------
40 //
41 // Low-level file input and output for OpenEXR.
42 //
43 //-----------------------------------------------------------------------------
44 
45 #include "ImfInt64.h"
46 #include "ImfNamespace.h"
47 #include "ImfExport.h"
48 
49 #include <string>
50 
51 
53 
54 //-----------------------------------------------------------
55 // class IStream -- an abstract base class for input streams.
56 //-----------------------------------------------------------
57 
59 {
60  public:
61 
62  //-----------
63  // Destructor
64  //-----------
65 
66  virtual ~IStream ();
67 
68 
69  //-------------------------------------------------
70  // Does this input stream support memory-mapped IO?
71  //
72  // Memory-mapped streams can avoid an extra copy;
73  // memory-mapped read operations return a pointer
74  // to an internal buffer instead of copying data
75  // into a buffer supplied by the caller.
76  //-------------------------------------------------
77 
78  virtual bool isMemoryMapped () const;
79 
80 
81  //------------------------------------------------------
82  // Read from the stream:
83  //
84  // read(c,n) reads n bytes from the stream, and stores
85  // them in array c. If the stream contains less than n
86  // bytes, or if an I/O error occurs, read(c,n) throws
87  // an exception. If read(c,n) reads the last byte from
88  // the file it returns false, otherwise it returns true.
89  //------------------------------------------------------
90 
91  virtual bool read (char c[/*n*/], int n) = 0;
92 
93 
94  //---------------------------------------------------
95  // Read from a memory-mapped stream:
96  //
97  // readMemoryMapped(n) reads n bytes from the stream
98  // and returns a pointer to the first byte. The
99  // returned pointer remains valid until the stream
100  // is closed. If there are less than n byte left to
101  // read in the stream or if the stream is not memory-
102  // mapped, readMemoryMapped(n) throws an exception.
103  //---------------------------------------------------
104 
105  virtual char * readMemoryMapped (int n);
106 
107 
108  //--------------------------------------------------------
109  // Get the current reading position, in bytes from the
110  // beginning of the file. If the next call to read() will
111  // read the first byte in the file, tellg() returns 0.
112  //--------------------------------------------------------
113 
114  virtual Int64 tellg () = 0;
115 
116 
117  //-------------------------------------------
118  // Set the current reading position.
119  // After calling seekg(i), tellg() returns i.
120  //-------------------------------------------
121 
122  virtual void seekg (Int64 pos) = 0;
123 
124 
125  //------------------------------------------------------
126  // Clear error conditions after an operation has failed.
127  //------------------------------------------------------
128 
129  virtual void clear ();
130 
131 
132  //------------------------------------------------------
133  // Get the name of the file associated with this stream.
134  //------------------------------------------------------
135 
136  const char * fileName () const;
137 
138  protected:
139 
140  IStream (const char fileName[]);
141 
142  private:
143 
144  IStream (const IStream &); // not implemented
145  IStream & operator = (const IStream &); // not implemented
146 
147  std::string _fileName;
148 };
149 
150 
151 //-----------------------------------------------------------
152 // class OStream -- an abstract base class for output streams
153 //-----------------------------------------------------------
154 
156 {
157  public:
158 
159  //-----------
160  // Destructor
161  //-----------
162 
163  virtual ~OStream ();
164 
165 
166  //----------------------------------------------------------
167  // Write to the stream:
168  //
169  // write(c,n) takes n bytes from array c, and stores them
170  // in the stream. If an I/O error occurs, write(c,n) throws
171  // an exception.
172  //----------------------------------------------------------
173 
174  virtual void write (const char c[/*n*/], int n) = 0;
175 
176 
177  //---------------------------------------------------------
178  // Get the current writing position, in bytes from the
179  // beginning of the file. If the next call to write() will
180  // start writing at the beginning of the file, tellp()
181  // returns 0.
182  //---------------------------------------------------------
183 
184  virtual Int64 tellp () = 0;
185 
186 
187  //-------------------------------------------
188  // Set the current writing position.
189  // After calling seekp(i), tellp() returns i.
190  //-------------------------------------------
191 
192  virtual void seekp (Int64 pos) = 0;
193 
194 
195  //------------------------------------------------------
196  // Get the name of the file associated with this stream.
197  //------------------------------------------------------
198 
199  const char * fileName () const;
200 
201  protected:
202 
203  OStream (const char fileName[]);
204 
205  private:
206 
207  OStream (const OStream &); // not implemented
208  OStream & operator = (const OStream &); // not implemented
209 
210  std::string _fileName;
211 };
212 
213 
214 //-----------------------
215 // Helper classes for Xdr
216 //-----------------------
217 
218 struct StreamIO
219 {
220  static void
221  writeChars (OStream &os, const char c[/*n*/], int n)
222  {
223  os.write (c, n);
224  }
225 
226  static bool
227  readChars (IStream &is, char c[/*n*/], int n)
228  {
229  return is.read (c, n);
230  }
231 };
232 
233 
234 struct CharPtrIO
235 {
236  static void
237  writeChars (char *&op, const char c[/*n*/], int n)
238  {
239  while (n--)
240  *op++ = *c++;
241  }
242 
243  static bool
244  readChars (const char *&ip, char c[/*n*/], int n)
245  {
246  while (n--)
247  *c++ = *ip++;
248 
249  return true;
250  }
251 };
252 
254 
255 #endif
static void writeChars(OStream &os, const char c[], int n)
Definition: ImfIO.h:221
Definition: ImfIO.h:58
#define OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_EXIT
Definition: ImfNamespace.h:109
GLsizei const GLchar *const * string
Definition: glcorearb.h:813
static bool readChars(IStream &is, char c[], int n)
Definition: ImfIO.h:227
void read(T &in, bool &v)
Definition: ImfXdr.h:611
Definition: ImfIO.h:155
virtual void write(const char c[], int n)=0
virtual bool read(char c[], int n)=0
static bool readChars(const char *&ip, char c[], int n)
Definition: ImfIO.h:244
GLdouble n
Definition: glcorearb.h:2007
IMATH_INTERNAL_NAMESPACE_HEADER_ENTER typedef long long unsigned int Int64
Definition: ImathInt64.h:56
#define IMF_EXPORT
Definition: ImfExport.h:59
static void writeChars(char *&op, const char c[], int n)
Definition: ImfIO.h:237
#define OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_ENTER
Definition: ImfNamespace.h:108
void write(T &out, bool v)
Definition: ImfXdr.h:332