]> git.saurik.com Git - wxWidgets.git/blob - include/wx/file.h
cleanup
[wxWidgets.git] / include / wx / file.h
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: file.h
3 // Purpose: wxFile - encapsulates low-level "file descriptor"
4 // wxTempFile - safely replace the old file
5 // Author: Vadim Zeitlin
6 // Modified by:
7 // Created: 29/01/98
8 // RCS-ID: $Id$
9 // Copyright: (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
10 // Licence: wxWindows licence
11 /////////////////////////////////////////////////////////////////////////////
12
13 #ifndef _WX_FILEH__
14 #define _WX_FILEH__
15
16 #include "wx/defs.h"
17
18 #if wxUSE_FILE
19
20 #include "wx/string.h"
21 #include "wx/filefn.h"
22 #include "wx/strconv.h"
23
24 // ----------------------------------------------------------------------------
25 // constants
26 // ----------------------------------------------------------------------------
27
28 // we redefine these constants here because S_IREAD &c are _not_ standard
29 // however, we do assume that the values correspond to the Unix umask bits
30 #define wxS_IRUSR 00400
31 #define wxS_IWUSR 00200
32 #define wxS_IXUSR 00100
33
34 #define wxS_IRGRP 00040
35 #define wxS_IWGRP 00020
36 #define wxS_IXGRP 00010
37
38 #define wxS_IROTH 00004
39 #define wxS_IWOTH 00002
40 #define wxS_IXOTH 00001
41
42 // default mode for the new files: corresponds to umask 022
43 #define wxS_DEFAULT (wxS_IRUSR | wxS_IWUSR | wxS_IRGRP | wxS_IWGRP |\
44 wxS_IROTH | wxS_IWOTH)
45
46 // ----------------------------------------------------------------------------
47 // class wxFile: raw file IO
48 //
49 // NB: for space efficiency this class has no virtual functions, including
50 // dtor which is _not_ virtual, so it shouldn't be used as a base class.
51 // ----------------------------------------------------------------------------
52
53 class WXDLLIMPEXP_BASE wxFile
54 {
55 public:
56 // more file constants
57 // -------------------
58 // opening mode
59 enum OpenMode { read, write, read_write, write_append, write_excl };
60 // standard values for file descriptor
61 enum { fd_invalid = -1, fd_stdin, fd_stdout, fd_stderr };
62
63 // static functions
64 // ----------------
65 // check whether a regular file by this name exists
66 static bool Exists(const wxString& name);
67 // check whether we can access the given file in given mode
68 // (only read and write make sense here)
69 static bool Access(const wxString& name, OpenMode mode);
70
71 // ctors
72 // -----
73 // def ctor
74 wxFile() { m_fd = fd_invalid; m_error = false; }
75 // open specified file (may fail, use IsOpened())
76 wxFile(const wxString& fileName, OpenMode mode = read);
77 // attach to (already opened) file
78 wxFile(int lfd) { m_fd = lfd; m_error = false; }
79
80 // open/close
81 // create a new file (with the default value of bOverwrite, it will fail if
82 // the file already exists, otherwise it will overwrite it and succeed)
83 bool Create(const wxString& fileName, bool bOverwrite = false,
84 int access = wxS_DEFAULT);
85 bool Open(const wxString& fileName, OpenMode mode = read,
86 int access = wxS_DEFAULT);
87 bool Close(); // Close is a NOP if not opened
88
89 // assign an existing file descriptor and get it back from wxFile object
90 void Attach(int lfd) { Close(); m_fd = lfd; m_error = false; }
91 void Detach() { m_fd = fd_invalid; }
92 int fd() const { return m_fd; }
93
94 // read/write (unbuffered)
95 // returns number of bytes read or wxInvalidOffset on error
96 ssize_t Read(void *pBuf, size_t nCount);
97 // returns the number of bytes written
98 size_t Write(const void *pBuf, size_t nCount);
99 // returns true on success
100 bool Write(const wxString& s, const wxMBConv& conv = wxMBConvUTF8());
101 // flush data not yet written
102 bool Flush();
103
104 // file pointer operations (return wxInvalidOffset on failure)
105 // move ptr ofs bytes related to start/current offset/end of file
106 wxFileOffset Seek(wxFileOffset ofs, wxSeekMode mode = wxFromStart);
107 // move ptr to ofs bytes before the end
108 wxFileOffset SeekEnd(wxFileOffset ofs = 0) { return Seek(ofs, wxFromEnd); }
109 // get current offset
110 wxFileOffset Tell() const;
111 // get current file length
112 wxFileOffset Length() const;
113
114 // simple accessors
115 // is file opened?
116 bool IsOpened() const { return m_fd != fd_invalid; }
117 // is end of file reached?
118 bool Eof() const;
119 // has an error occurred?
120 bool Error() const { return m_error; }
121 // type such as disk or pipe
122 wxFileKind GetKind() const { return wxGetFileKind(m_fd); }
123
124 // dtor closes the file if opened
125 ~wxFile() { Close(); }
126
127 private:
128 // copy ctor and assignment operator are private because
129 // it doesn't make sense to copy files this way:
130 // attempt to do it will provoke a compile-time error.
131 wxFile(const wxFile&);
132 wxFile& operator=(const wxFile&);
133
134 int m_fd; // file descriptor or INVALID_FD if not opened
135 bool m_error; // error memory
136 };
137
138 // ----------------------------------------------------------------------------
139 // class wxTempFile: if you want to replace another file, create an instance
140 // of wxTempFile passing the name of the file to be replaced to the ctor. Then
141 // you can write to wxTempFile and call Commit() function to replace the old
142 // file (and close this one) or call Discard() to cancel the modification. If
143 // you call neither of them, dtor will call Discard().
144 // ----------------------------------------------------------------------------
145
146 class WXDLLIMPEXP_BASE wxTempFile
147 {
148 public:
149 // ctors
150 // default
151 wxTempFile() { }
152 // associates the temp file with the file to be replaced and opens it
153 wxTempFile(const wxString& strName);
154
155 // open the temp file (strName is the name of file to be replaced)
156 bool Open(const wxString& strName);
157
158 // is the file opened?
159 bool IsOpened() const { return m_file.IsOpened(); }
160 // get current file length
161 wxFileOffset Length() const { return m_file.Length(); }
162 // move ptr ofs bytes related to start/current offset/end of file
163 wxFileOffset Seek(wxFileOffset ofs, wxSeekMode mode = wxFromStart)
164 { return m_file.Seek(ofs, mode); }
165 // get current offset
166 wxFileOffset Tell() const { return m_file.Tell(); }
167
168 // I/O (both functions return true on success, false on failure)
169 bool Write(const void *p, size_t n) { return m_file.Write(p, n) == n; }
170 bool Write(const wxString& str, const wxMBConv& conv = wxMBConvUTF8())
171 { return m_file.Write(str, conv); }
172
173 // different ways to close the file
174 // validate changes and delete the old file of name m_strName
175 bool Commit();
176 // discard changes
177 void Discard();
178
179 // dtor calls Discard() if file is still opened
180 ~wxTempFile();
181
182 private:
183 // no copy ctor/assignment operator
184 wxTempFile(const wxTempFile&);
185 wxTempFile& operator=(const wxTempFile&);
186
187 wxString m_strName, // name of the file to replace in Commit()
188 m_strTemp; // temporary file name
189 wxFile m_file; // the temporary file
190 };
191
192 #endif // wxUSE_FILE
193
194 #endif // _WX_FILEH__