file_utils.cpp

   1 /*
   2 Project: J-Ben
   3 Author:  Paul Goins
   4 License: GNU General Public License (GPL) version 2
   5          (http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt)
   6
   7 File: file_utils.cpp
   8
   9 This file is part of J-Ben.
  10
  11 J-Ben is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU General Public License version 2
  13 as published by the Free Software Foundation.
  14
  15 J-Ben is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with this program.  If not, see <http://www.gnu.org/licenses/>
  22 */
  23
  24 #include "file_utils.h"
  25 #include "wx/file.h"
  26 #include "wx/ffile.h"
  27 #include "wx/strconv.h"
  28
  29 /* Tries to open the specified file.  If successful, it'll read in its entire
  30    contents into a wxString, and apply the specified conversion. */
  31 int ReadEncodedFile(const wxChar *filename, const wxChar *src_encoding, wxString& dest) {
  32         /* Read in the file.  NOTE: a "b" flag MIGHT be necessary for
  33            Windows! */
  34         if(wxFile::Exists(filename)) {
  35                 wxFFile *in = new wxFFile(filename, _T("r"));
  36                 if(!in->IsOpened()) {  /* Bail if we couldn't read it */
  37                         delete in;
  38                         return REF_FILE_OPEN_ERROR;
  39                 }
  40
  41                 /* Read in all the data - our files are "small", so we'll be lazy
  42                 and "read all". */
  43                 /* NOTE: Workaround for SLOW GTK performance
  44                         provided by "doublemax" on wxforum.shadonet.com.
  45                 What happens:
  46                 1. Standard C functions are used to get the raw file size
  47                 2. The file is read in using the wxFFile::Read() command instead of
  48                 ReadAll().  Read does not perform local encoding to Unicode
  49                 conversion.
  50                 3. Use the wxString::GetWriteBuf function to get us a buffer to receive
  51                 the wide character conversion.  File length * 2 is used, which isn't
  52                 very memory efficient, but is CPU-efficient - far more important.
  53                 4. wxCSConv::MB2WC is called to perform the conversion after the file
  54                 is loaded.  This happens FAST. */
  55
  56                 size_t length = (size_t)in->Length();
  57                 wxCharBuffer buf(length+1);
  58                 length = in->Read(buf.data(), length);
  59                 buf.data()[length]=_T('\0');
  60                 in->Close();
  61                 delete in;
  62
  63                 wxCSConv transcoder(src_encoding);
  64
  65                 length++;  /* Incremented so we will include the null character as part of
  66                               the copied string. */
  67                 transcoder.MB2WC(dest.GetWriteBuf(length*2), buf.data(), length);
  68                 dest.UngetWriteBuf();
  69
  70                 return REF_SUCCESS;
  71         } else return REF_FILE_NOT_FOUND;
  72 }
  73
  74 /* Tries to open the specified file.  If successful, it'll read in its entire
  75    contents into a wxString, and apply the local-to-Unicode conversion.
  76    (Yes, this is -another- ugly workaround for just doing a wxFFile::ReadAll.)
  77    */
  78 int ReadFile(const wxChar *filename, wxString& dest) {
  79         /* Read in the file.  NOTE: a "b" flag MIGHT be necessary for
  80            Windows! */
  81         if(wxFile::Exists(filename)) {
  82                 wxFFile *in = new wxFFile(filename, _T("r"));
  83                 if(!in->IsOpened()) {  /* Bail if we couldn't read it */
  84                         delete in;
  85                         return REF_FILE_OPEN_ERROR;
  86                 }
  87
  88                 size_t length = (size_t)in->Length();
  89                 wxCharBuffer buf(length+1);
  90                 length = in->Read(buf.data(), length);
  91                 buf.data()[length]=_T('\0');
  92                 in->Close();
  93                 delete in;
  94
  95                 length++;  /* Incremented so we will include the null character as part of
  96                         the copied string. */
  97                 wxConvCurrent->MB2WC(dest.GetWriteBuf(length*2), buf.data(), length);
  98                 dest.UngetWriteBuf();
  99
 100                 return REF_SUCCESS;
 101         } else {
 102 #ifdef DEBUG
 103                 printf("Could not find file \"%ls\".\n", filename);
 104 #endif
 105                 return REF_FILE_NOT_FOUND;
 106         }
 107 }