Aegisub/aegisub/src/text_file_reader.cpp
Amar Takhar d348b4e33e Fix all the headers in *.cpp, this includes:
* Wrapping all headers that are in agi_pre.h with AGI_PRE.
 * Sorting alphabetically.

Originally committed to SVN as r3515.
2009-09-10 13:06:40 +00:00

258 lines
7 KiB
C++

// Copyright (c) 2005, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Aegisub Project http://www.aegisub.org/
//
// $Id$
/// @file text_file_reader.cpp
/// @brief Read plain text files line by line
/// @ingroup utility
///
#include "config.h"
#ifndef AGI_PRE
#include <assert.h>
#include <errno.h>
#include <algorithm>
#include <fstream>
#include <string>
#endif
#include "charset_conv.h"
#ifdef WITH_UNIVCHARDET
#include "charset_detect.h"
#endif
#include "text_file_reader.h"
/// @brief DOCME
/// @param filename
/// @param enc
/// @param trim
/// @return
///
TextFileReader::TextFileReader(wxString filename, wxString enc, bool trim)
: encoding(enc), conv((iconv_t)-1), trim(trim), readComplete(false), currout(0), outptr(0), currentLine(0) {
#ifdef __WINDOWS__
file.open(filename.wc_str(),std::ios::in | std::ios::binary);
#else
file.open(wxFNCONV(filename),std::ios::in | std::ios::binary);
#endif
if (!file.is_open()) {
throw _T("Failed opening file for reading.");
}
if (encoding.IsEmpty()) encoding = GetEncoding(filename);
if (encoding == _T("binary")) return;
encoding = AegisubCSConv::GetRealEncodingName(encoding);
conv = iconv_open(WCHAR_T_ENCODING, encoding.ToAscii());
}
/// @brief DOCME
///
TextFileReader::~TextFileReader() {
if (conv != (iconv_t)-1) iconv_close(conv);
}
/// @brief DOCME
/// @param filename
/// @return
///
wxString TextFileReader::GetEncoding(const wxString filename) {
// Prepare
unsigned char b[4];
memset(b, 0, sizeof(b));
// Read four bytes from file
std::ifstream ifile;
#ifdef __WINDOWS__
ifile.open(filename.wc_str());
#else
ifile.open(wxFNCONV(filename));
#endif
if (!ifile.is_open()) {
return _T("unknown");
}
ifile.read(reinterpret_cast<char *>(b),4);
ifile.close();
// Try to get the byte order mark from them
if (b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF) return _T("UTF-8");
else if (b[0] == 0xFF && b[1] == 0xFE && b[2] == 0x00 && b[3] == 0x00) return _T("UTF-32LE");
else if (b[0] == 0x00 && b[1] == 0x00 && b[2] == 0xFE && b[3] == 0xFF) return _T("UTF-32BE");
else if (b[0] == 0xFF && b[1] == 0xFE) return _T("UTF-16LE");
else if (b[0] == 0xFE && b[1] == 0xFF) return _T("UTF-16BE");
else if (b[0] == 0x2B && b[1] == 0x2F && b[2] == 0x76) return _T("UTF-7");
// Try to guess UTF-16
else if (b[0] == 0 && b[1] >= 32 && b[2] == 0 && b[3] >= 32) return _T("UTF-16BE");
else if (b[0] >= 32 && b[1] == 0 && b[2] >= 32 && b[3] == 0) return _T("UTF-16LE");
// If any of the first four bytes are under 0x20 (the first printable character),
// except for 9-13 range, assume binary
for (int i=0;i<4;i++) {
if (b[i] < 9 || (b[i] > 13 && b[i] < 32)) return _T("binary");
}
#ifdef WITH_UNIVCHARDET
// Use universalchardet library to detect charset
CharSetDetect det;
return det.GetEncoding(filename);
#else
// Fall back to local
return _T("Local");
#endif
}
/// @brief DOCME
/// @return
///
wchar_t TextFileReader::GetWChar() {
// If there's already some converted characters waiting, return the next one
if (++currout < outptr) {
return *currout;
}
if (file.eof()) return 0;
// Otherwise convert another block
char inbuf[64];
char *inptr = inbuf;
size_t inbytesleft = sizeof(inbuf) - 4;
int bytesAdded = 0;
memset(inbuf, 0, inbytesleft);
outptr = outbuf;
outbytesleft = sizeof(outbuf);
currout = outbuf;
file.read(inbuf, inbytesleft);
inbytesleft = file.gcount();
if (inbytesleft == 0)
return 0;
do {
size_t ret = iconv(conv, &inptr, &inbytesleft, reinterpret_cast<char **>(&outptr), &outbytesleft);
if (ret != (size_t)-1) break;
int err = errno;
// If 64 chars do not fit into 256 wchar_ts the environment is so bizzare that doing
// anything is probably futile
assert(err != E2BIG);
// (Hopefully) the edge of the buffer happened to split a multibyte character, so keep
// adding one byte to the input buffer until either it succeeds or we add enough bytes to
// complete any character
if (++bytesAdded > 3)
throw wxString::Format(_T("Invalid input character found near line %u"), currentLine);
file.read(inptr + inbytesleft, 1);
inbytesleft++;
} while (!file.eof() && file.gcount());
if (outptr > outbuf)
return *currout;
throw wxString::Format(_T("Invalid input character found near line %u"), currentLine);
}
/// @brief DOCME
/// @return
///
wxString TextFileReader::ReadLineFromFile() {
wxString buffer;
size_t bufAlloc = 1024;
buffer.Alloc(bufAlloc);
currentLine++;
// Read a line
wchar_t ch;
size_t len = 0;
for (ch = GetWChar(); ch != L'\n' && ch != 0; ch = GetWChar()) {
if (ch == L'\r') continue;
// Skip the BOM -- we don't need it as the encoding is already known
// and it sometimes causes conversion problems
if (ch == 0xFEFF && len == 0) continue;
if (len >= bufAlloc - 1) {
bufAlloc *= 2;
buffer.Alloc(bufAlloc);
}
buffer += ch;
len++;
}
if (ch == 0)
readComplete = true;
// Trim
if (trim) {
buffer.Trim(true);
buffer.Trim(false);
}
return buffer;
}
/// @brief DOCME
/// @return
///
bool TextFileReader::HasMoreLines() {
return !readComplete;
}
/// @brief DOCME
/// @param encoding
/// @return
///
void TextFileReader::EnsureValid(wxString enc) {
if (enc == _T("binary")) return;
enc = AegisubCSConv::GetRealEncodingName(enc);
iconv_t cd = iconv_open(WCHAR_T_ENCODING, enc.ToAscii());
bool canOpen = cd != (iconv_t)-1;
iconv_close(cd);
if (!canOpen) {
throw wxString::Format(_T("Character set %s is not supported."), enc.c_str());
}
}
/// @brief DOCME
///
wxString TextFileReader::GetCurrentEncoding() {
return encoding;
}