1 | /* $Id: CoinFileIO.hpp 1448 2011-06-19 15:34:41Z stefan $ */ |
2 | // Copyright (C) 2005, COIN-OR. All Rights Reserved. |
3 | // This code is licensed under the terms of the Eclipse Public License (EPL). |
4 | |
5 | #ifndef CoinFileIO_H |
6 | #define CoinFileIO_H |
7 | |
8 | #include <string> |
9 | |
10 | /// Base class for FileIO classes. |
11 | class CoinFileIOBase |
12 | { |
13 | public: |
14 | /// Constructor. |
15 | /// @param fileName The name of the file used by this object. |
16 | CoinFileIOBase (const std::string &fileName); |
17 | |
18 | /// Destructor. |
19 | ~CoinFileIOBase (); |
20 | |
21 | /// Return the name of the file used by this object. |
22 | const char *getFileName () const; |
23 | |
24 | /// Return the method of reading being used |
25 | inline std::string getReadType () const |
26 | { return readType_.c_str();} |
27 | protected: |
28 | std::string readType_; |
29 | private: |
30 | CoinFileIOBase (); |
31 | CoinFileIOBase (const CoinFileIOBase &); |
32 | |
33 | std::string fileName_; |
34 | }; |
35 | |
36 | /// Abstract base class for file input classes. |
37 | class CoinFileInput: public CoinFileIOBase |
38 | { |
39 | public: |
40 | /// indicates whether CoinFileInput supports gzip'ed files |
41 | static bool haveGzipSupport(); |
42 | /// indicates whether CoinFileInput supports bzip2'ed files |
43 | static bool haveBzip2Support(); |
44 | |
45 | /// Factory method, that creates a CoinFileInput (more precisely |
46 | /// a subclass of it) for the file specified. This method reads the |
47 | /// first few bytes of the file and determines if this is a compressed |
48 | /// or a plain file and returns the correct subclass to handle it. |
49 | /// If the file does not exist or uses a compression not compiled in |
50 | /// an exception is thrown. |
51 | /// @param fileName The file that should be read. |
52 | static CoinFileInput *create (const std::string &fileName); |
53 | |
54 | /// Constructor (don't use this, use the create method instead). |
55 | /// @param fileName The name of the file used by this object. |
56 | CoinFileInput (const std::string &fileName); |
57 | |
58 | /// Destructor. |
59 | virtual ~CoinFileInput (); |
60 | |
61 | /// Read a block of data from the file, similar to fread. |
62 | /// @param buffer Address of a buffer to store the data into. |
63 | /// @param size Number of bytes to read (buffer should be large enough). |
64 | /// @return Number of bytes read. |
65 | virtual int read (void *buffer, int size) = 0; |
66 | |
67 | /// Reads up to (size-1) characters an stores them into the buffer, |
68 | /// similar to fgets. |
69 | /// Reading ends, when EOF or a newline occurs or (size-1) characters have |
70 | /// been read. The resulting string is terminated with '\0'. If reading |
71 | /// ends due to an encoutered newline, the '\n' is put into the buffer, |
72 | /// before the '\0' is appended. |
73 | /// @param buffer The buffer to put the string into. |
74 | /// @param size The size of the buffer in characters. |
75 | /// @return buffer on success, or 0 if no characters have been read. |
76 | virtual char *gets (char *buffer, int size) = 0; |
77 | }; |
78 | |
79 | /// Abstract base class for file output classes. |
80 | class CoinFileOutput: public CoinFileIOBase |
81 | { |
82 | public: |
83 | |
84 | /// The compression method. |
85 | enum Compression { |
86 | COMPRESS_NONE = 0, ///< No compression. |
87 | COMPRESS_GZIP = 1, ///< gzip compression. |
88 | COMPRESS_BZIP2 = 2 ///< bzip2 compression. |
89 | }; |
90 | |
91 | /// Returns whether the specified compression method is supported |
92 | /// (i.e. was compiled into COIN). |
93 | static bool compressionSupported (Compression compression); |
94 | |
95 | /// Factory method, that creates a CoinFileOutput (more precisely |
96 | /// a subclass of it) for the file specified. If the compression method |
97 | /// is not supported an exception is thrown (so use compressionSupported |
98 | /// first, if this is a problem). The reason for not providing direct |
99 | /// access to the subclasses (and using such a method instead) is that |
100 | /// depending on the build configuration some of the classes are not |
101 | /// available (or functional). This way we can handle all required ifdefs |
102 | /// here instead of polluting other files. |
103 | /// @param fileName The file that should be read. |
104 | /// @param compression Compression method used. |
105 | static CoinFileOutput *create (const std::string &fileName, |
106 | Compression compression); |
107 | |
108 | /// Constructor (don't use this, use the create method instead). |
109 | /// @param fileName The name of the file used by this object. |
110 | CoinFileOutput (const std::string &fileName); |
111 | |
112 | /// Destructor. |
113 | virtual ~CoinFileOutput (); |
114 | |
115 | /// Write a block of data to the file, similar to fwrite. |
116 | /// @param buffer Address of a buffer containing the data to be written. |
117 | /// @param size Number of bytes to write. |
118 | /// @return Number of bytes written. |
119 | virtual int write (const void * buffer, int size) = 0; |
120 | |
121 | /// Write a string to the file (like fputs). |
122 | /// Just as with fputs no trailing newline is inserted! |
123 | /// The terminating '\0' is not written to the file. |
124 | /// The default implementation determines the length of the string |
125 | /// and calls write on it. |
126 | /// @param s The zero terminated string to be written. |
127 | /// @return true on success, false on error. |
128 | virtual bool puts (const char *s); |
129 | |
130 | /// Convenience method: just a 'puts(s.c_str())'. |
131 | inline bool puts (const std::string &s) |
132 | { |
133 | return puts (s.c_str ()); |
134 | } |
135 | }; |
136 | |
137 | /*! \relates CoinFileInput |
138 | \brief Test if the given string looks like an absolute file path |
139 | |
140 | The criteria are: |
141 | - unix: string begins with `/' |
142 | - windows: string begins with `\' or with `drv:' (drive specifier) |
143 | */ |
144 | bool fileAbsPath (const std::string &path) ; |
145 | |
146 | /*! \relates CoinFileInput |
147 | \brief Test if the file is readable, using likely versions of the file |
148 | name, and return the name that worked. |
149 | |
150 | The file name is constructed from \p name using the following rules: |
151 | <ul> |
152 | <li> An absolute path is not modified. |
153 | <li> If the name begins with `~', an attempt is made to replace `~' |
154 | with the value of the environment variable HOME. |
155 | <li> If a default prefix (\p dfltPrefix) is provided, it is |
156 | prepended to the name. |
157 | </ul> |
158 | If the constructed file name cannot be opened, and CoinUtils was built |
159 | with support for compressed files, fileCoinReadable will try any |
160 | standard extensions for supported compressed files. |
161 | |
162 | The value returned in \p name is the file name that actually worked. |
163 | */ |
164 | bool (std::string &name, |
165 | const std::string &dfltPrefix = std::string("" )); |
166 | #endif |
167 | |