| 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 | #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA) |
| 17 | #pragma interface "file.h" |
| 18 | #endif |
| 19 | |
| 20 | #include "wx/defs.h" |
| 21 | |
| 22 | #if wxUSE_FILE |
| 23 | |
| 24 | #include "wx/string.h" |
| 25 | #include "wx/filefn.h" |
| 26 | #include "wx/strconv.h" |
| 27 | |
| 28 | // ---------------------------------------------------------------------------- |
| 29 | // constants |
| 30 | // ---------------------------------------------------------------------------- |
| 31 | |
| 32 | // we redefine these constants here because S_IREAD &c are _not_ standard |
| 33 | // however, we do assume that the values correspond to the Unix umask bits |
| 34 | #define wxS_IRUSR 00400 |
| 35 | #define wxS_IWUSR 00200 |
| 36 | #define wxS_IXUSR 00100 |
| 37 | |
| 38 | #define wxS_IRGRP 00040 |
| 39 | #define wxS_IWGRP 00020 |
| 40 | #define wxS_IXGRP 00010 |
| 41 | |
| 42 | #define wxS_IROTH 00004 |
| 43 | #define wxS_IWOTH 00002 |
| 44 | #define wxS_IXOTH 00001 |
| 45 | |
| 46 | // default mode for the new files: corresponds to umask 022 |
| 47 | #define wxS_DEFAULT (wxS_IRUSR | wxS_IWUSR | wxS_IRGRP | wxS_IWGRP |\ |
| 48 | wxS_IROTH | wxS_IWOTH) |
| 49 | |
| 50 | // ---------------------------------------------------------------------------- |
| 51 | // class wxFile: raw file IO |
| 52 | // |
| 53 | // NB: for space efficiency this class has no virtual functions, including |
| 54 | // dtor which is _not_ virtual, so it shouldn't be used as a base class. |
| 55 | // ---------------------------------------------------------------------------- |
| 56 | |
| 57 | class WXDLLIMPEXP_BASE wxFile |
| 58 | { |
| 59 | public: |
| 60 | // more file constants |
| 61 | // ------------------- |
| 62 | // opening mode |
| 63 | enum OpenMode { read, write, read_write, write_append, write_excl }; |
| 64 | // standard values for file descriptor |
| 65 | enum { fd_invalid = -1, fd_stdin, fd_stdout, fd_stderr }; |
| 66 | |
| 67 | // static functions |
| 68 | // ---------------- |
| 69 | // check whether a regular file by this name exists |
| 70 | static bool Exists(const wxChar *name); |
| 71 | // check whether we can access the given file in given mode |
| 72 | // (only read and write make sense here) |
| 73 | static bool Access(const wxChar *name, OpenMode mode); |
| 74 | |
| 75 | // ctors |
| 76 | // ----- |
| 77 | // def ctor |
| 78 | wxFile() { m_fd = fd_invalid; m_error = false; } |
| 79 | // open specified file (may fail, use IsOpened()) |
| 80 | wxFile(const wxChar *szFileName, OpenMode mode = read); |
| 81 | // attach to (already opened) file |
| 82 | wxFile(int fd) { m_fd = fd; m_error = false; } |
| 83 | |
| 84 | // open/close |
| 85 | // create a new file (with the default value of bOverwrite, it will fail if |
| 86 | // the file already exists, otherwise it will overwrite it and succeed) |
| 87 | bool Create(const wxChar *szFileName, bool bOverwrite = false, |
| 88 | int access = wxS_DEFAULT); |
| 89 | bool Open(const wxChar *szFileName, OpenMode mode = read, |
| 90 | int access = wxS_DEFAULT); |
| 91 | bool Close(); // Close is a NOP if not opened |
| 92 | |
| 93 | // assign an existing file descriptor and get it back from wxFile object |
| 94 | void Attach(int fd) { Close(); m_fd = fd; m_error = false; } |
| 95 | void Detach() { m_fd = fd_invalid; } |
| 96 | int fd() const { return m_fd; } |
| 97 | |
| 98 | // read/write (unbuffered) |
| 99 | // returns number of bytes read or wxInvalidOffset on error |
| 100 | ssize_t Read(void *pBuf, size_t nCount); |
| 101 | // returns the number of bytes written |
| 102 | size_t Write(const void *pBuf, size_t nCount); |
| 103 | // returns true on success |
| 104 | bool Write(const wxString& s, wxMBConv& conv = wxConvUTF8) |
| 105 | { |
| 106 | const wxWX2MBbuf buf = s.mb_str(conv); |
| 107 | size_t size = strlen(buf); |
| 108 | return Write((const char *) buf, size) == size; |
| 109 | } |
| 110 | // flush data not yet written |
| 111 | bool Flush(); |
| 112 | |
| 113 | // file pointer operations (return wxInvalidOffset on failure) |
| 114 | // move ptr ofs bytes related to start/current offset/end of file |
| 115 | wxFileOffset Seek(wxFileOffset ofs, wxSeekMode mode = wxFromStart); |
| 116 | // move ptr to ofs bytes before the end |
| 117 | wxFileOffset SeekEnd(wxFileOffset ofs = 0) { return Seek(ofs, wxFromEnd); } |
| 118 | // get current offset |
| 119 | wxFileOffset Tell() const; |
| 120 | // get current file length |
| 121 | wxFileOffset Length() const; |
| 122 | |
| 123 | // simple accessors |
| 124 | // is file opened? |
| 125 | bool IsOpened() const { return m_fd != fd_invalid; } |
| 126 | // is end of file reached? |
| 127 | bool Eof() const; |
| 128 | // has an error occured? |
| 129 | bool Error() const { return m_error; } |
| 130 | // type such as disk or pipe |
| 131 | wxFileKind GetKind() const { return wxGetFileKind(m_fd); } |
| 132 | |
| 133 | // dtor closes the file if opened |
| 134 | ~wxFile() { Close(); } |
| 135 | |
| 136 | private: |
| 137 | // copy ctor and assignment operator are private because |
| 138 | // it doesn't make sense to copy files this way: |
| 139 | // attempt to do it will provoke a compile-time error. |
| 140 | wxFile(const wxFile&); |
| 141 | wxFile& operator=(const wxFile&); |
| 142 | |
| 143 | int m_fd; // file descriptor or INVALID_FD if not opened |
| 144 | bool m_error; // error memory |
| 145 | }; |
| 146 | |
| 147 | // ---------------------------------------------------------------------------- |
| 148 | // class wxTempFile: if you want to replace another file, create an instance |
| 149 | // of wxTempFile passing the name of the file to be replaced to the ctor. Then |
| 150 | // you can write to wxTempFile and call Commit() function to replace the old |
| 151 | // file (and close this one) or call Discard() to cancel the modification. If |
| 152 | // you call neither of them, dtor will call Discard(). |
| 153 | // ---------------------------------------------------------------------------- |
| 154 | |
| 155 | class WXDLLIMPEXP_BASE wxTempFile |
| 156 | { |
| 157 | public: |
| 158 | // ctors |
| 159 | // default |
| 160 | wxTempFile() { } |
| 161 | // associates the temp file with the file to be replaced and opens it |
| 162 | wxTempFile(const wxString& strName); |
| 163 | |
| 164 | // open the temp file (strName is the name of file to be replaced) |
| 165 | bool Open(const wxString& strName); |
| 166 | |
| 167 | // is the file opened? |
| 168 | bool IsOpened() const { return m_file.IsOpened(); } |
| 169 | // get current file length |
| 170 | wxFileOffset Length() const { return m_file.Length(); } |
| 171 | // move ptr ofs bytes related to start/current offset/end of file |
| 172 | wxFileOffset Seek(wxFileOffset ofs, wxSeekMode mode = wxFromStart) |
| 173 | { return m_file.Seek(ofs, mode); } |
| 174 | // get current offset |
| 175 | wxFileOffset Tell() const { return m_file.Tell(); } |
| 176 | |
| 177 | // I/O (both functions return true on success, false on failure) |
| 178 | bool Write(const void *p, size_t n) { return m_file.Write(p, n) == n; } |
| 179 | bool Write(const wxString& str, wxMBConv& conv = wxConvUTF8) |
| 180 | { return m_file.Write(str, conv); } |
| 181 | |
| 182 | // different ways to close the file |
| 183 | // validate changes and delete the old file of name m_strName |
| 184 | bool Commit(); |
| 185 | // discard changes |
| 186 | void Discard(); |
| 187 | |
| 188 | // dtor calls Discard() if file is still opened |
| 189 | ~wxTempFile(); |
| 190 | |
| 191 | private: |
| 192 | // no copy ctor/assignment operator |
| 193 | wxTempFile(const wxTempFile&); |
| 194 | wxTempFile& operator=(const wxTempFile&); |
| 195 | |
| 196 | wxString m_strName, // name of the file to replace in Commit() |
| 197 | m_strTemp; // temporary file name |
| 198 | wxFile m_file; // the temporary file |
| 199 | }; |
| 200 | |
| 201 | #endif // wxUSE_FILE |
| 202 | |
| 203 | #endif // _WX_FILEH__ |