Exercise: simplify the definition of IconvProcessor

It is no longer needed to create fake copy constructors and assignment and to
deal with deletion by hand, thanks to unique_ptr, the inference of move
constructor and assignment operator, and the compatibility of standard
containers with movable objects.
This commit is contained in:
Guillaume Munch 2016-06-02 22:27:52 +01:00
parent 8d640dc776
commit e87febd0de
2 changed files with 71 additions and 133 deletions

View File

@ -49,106 +49,66 @@ namespace lyx {
char const * ucs4_codeset = "UCS-4LE";
#endif
static const iconv_t invalid_cd = (iconv_t)(-1);
class IconvProcessor::Impl
{
public:
// noncopyable because iconv_close() is called in destructor
Impl(Impl const &) = delete;
Impl & operator=(Impl const &) = delete;
Impl(string const & to, string const & from)
: cd(invalid_cd), tocode_(to), fromcode_(from)
{}
~Impl()
{
if (cd != invalid_cd && iconv_close(cd) == -1)
struct IconvProcessor::Handler {
// assumes cd is valid
Handler(iconv_t const cd) : cd(cd) {}
~Handler() {
if (iconv_close(cd) == -1)
LYXERR0("Error returned from iconv_close(" << errno << ')');
}
iconv_t cd;
string tocode_;
string fromcode_;
iconv_t const cd;
};
IconvProcessor::IconvProcessor(char const * tocode, char const * fromcode)
: pimpl_(new IconvProcessor::Impl(tocode, fromcode))
{
}
IconvProcessor::IconvProcessor(IconvProcessor const & other)
: pimpl_(new IconvProcessor::Impl(other.pimpl_->tocode_, other.pimpl_->fromcode_))
{
}
IconvProcessor::~IconvProcessor()
{
delete pimpl_;
}
IconvProcessor & IconvProcessor::operator=(IconvProcessor const & other)
{
if (&other != this) {
delete pimpl_;
pimpl_ = new Impl(other.pimpl_->tocode_, other.pimpl_->fromcode_);
}
return *this;
}
IconvProcessor::IconvProcessor(string tocode, string fromcode)
: tocode_(tocode), fromcode_(fromcode)
{}
bool IconvProcessor::init()
{
if (pimpl_->cd != invalid_cd)
if (h_)
return true;
pimpl_->cd = iconv_open(pimpl_->tocode_.c_str(), pimpl_->fromcode_.c_str());
if (pimpl_->cd != invalid_cd)
iconv_t cd = iconv_open(tocode_.c_str(), fromcode_.c_str());
if (cd != (iconv_t)(-1)) {
h_ = make_unique<Handler>(cd);
return true;
}
lyxerr << "Error returned from iconv_open" << endl;
switch (errno) {
case EINVAL:
lyxerr << "EINVAL The conversion from " << pimpl_->fromcode_
<< " to " << pimpl_->tocode_
<< " is not supported by the implementation."
<< endl;
break;
default:
lyxerr << "\tSome other error: " << errno << endl;
break;
case EINVAL:
lyxerr << "EINVAL The conversion from " << fromcode_ << " to "
<< tocode_ << " is not supported by the implementation."
<< endl;
break;
default:
lyxerr << "\tSome other error: " << errno << endl;
break;
}
return false;
}
int IconvProcessor::convert(char const * buf, size_t buflen,
char * outbuf, size_t maxoutsize)
char * outbuf, size_t maxoutsize)
{
if (buflen == 0)
return 0;
if (pimpl_->cd == invalid_cd) {
if (!init())
return -1;
}
if (!h_ && !init())
return -1;
char ICONV_CONST * inbuf = const_cast<char ICONV_CONST *>(buf);
size_t inbytesleft = buflen;
size_t outbytesleft = maxoutsize;
int res = iconv(pimpl_->cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft);
int res = iconv(h_->cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft);
// flush out remaining data. This is needed because iconv sometimes
// holds back chars in the stream, waiting for a combination character
// (see e.g. http://sources.redhat.com/bugzilla/show_bug.cgi?id=1124)
iconv(pimpl_->cd, NULL, NULL, &outbuf, &outbytesleft);
iconv(h_->cd, NULL, NULL, &outbuf, &outbytesleft);
//lyxerr << dec;
//lyxerr << "Inbytesleft: " << inbytesleft << endl;
@ -167,8 +127,8 @@ int IconvProcessor::convert(char const * buf, size_t buflen,
case EILSEQ:
lyxerr << "EILSEQ An invalid multibyte sequence"
<< " has been encountered in the input.\n"
<< "When converting from " << pimpl_->fromcode_
<< " to " << pimpl_->tocode_ << ".\n";
<< "When converting from " << fromcode_
<< " to " << tocode_ << ".\n";
lyxerr << "Input:" << hex;
for (size_t i = 0; i < buflen; ++i) {
// char may be signed, avoid output of
@ -182,8 +142,8 @@ int IconvProcessor::convert(char const * buf, size_t buflen,
case EINVAL:
lyxerr << "EINVAL An incomplete multibyte sequence"
<< " has been encountered in the input.\n"
<< "When converting from " << pimpl_->fromcode_
<< " to " << pimpl_->tocode_ << ".\n";
<< "When converting from " << fromcode_
<< " to " << tocode_ << ".\n";
lyxerr << "Input:" << hex;
for (size_t i = 0; i < buflen; ++i) {
// char may be signed, avoid output of
@ -199,27 +159,11 @@ int IconvProcessor::convert(char const * buf, size_t buflen,
break;
}
// We got an error so we close down the conversion engine
if (iconv_close(pimpl_->cd) == -1) {
lyxerr << "Error returned from iconv_close("
<< errno << ")" << endl;
}
pimpl_->cd = invalid_cd;
h_.reset();
return -1;
}
std::string IconvProcessor::from() const
{
return pimpl_->fromcode_;
}
std::string IconvProcessor::to() const
{
return pimpl_->tocode_;
}
namespace {
@ -310,6 +254,23 @@ IconvProcessor & ucs4ToUtf8()
return *processor.localData();
}
namespace {
IconvProcessor & getProc(map<string, IconvProcessor> & processors,
string const & encoding, bool to)
{
string const & fromcode = to ? ucs4_codeset : encoding;
string const & tocode = to ? encoding : ucs4_codeset;
map<string, IconvProcessor>::iterator const it = processors.find(encoding);
if (it == processors.end()) {
IconvProcessor p(fromcode, tocode);
return processors.insert(make_pair(encoding, move(p))).first->second;
} else
return it->second;
}
} //anon namespace
vector<char>
ucs4_to_utf8(char_type c)
@ -342,11 +303,8 @@ eightbit_to_ucs4(char const * s, size_t ls, string const & encoding)
if (!static_processors.hasLocalData())
static_processors.setLocalData(new map<string, IconvProcessor>);
map<string, IconvProcessor> & processors = *static_processors.localData();
if (processors.find(encoding) == processors.end()) {
IconvProcessor processor(ucs4_codeset, encoding.c_str());
processors.insert(make_pair(encoding, processor));
}
return iconv_convert<char_type>(processors[encoding], s, ls);
IconvProcessor & processor = getProc(processors, encoding, true);
return iconv_convert<char_type>(processor, s, ls);
}
@ -362,30 +320,21 @@ map<string, IconvProcessor> & ucs4To8bitProcessors()
}
vector<char>
ucs4_to_eightbit(char_type const * ucs4str, size_t ls, string const & encoding)
{
map<string, IconvProcessor> & processors(ucs4To8bitProcessors());
if (processors.find(encoding) == processors.end()) {
IconvProcessor processor(encoding.c_str(), ucs4_codeset);
processors.insert(make_pair(encoding, processor));
}
return iconv_convert<char>(processors[encoding], ucs4str, ls);
IconvProcessor & processor = getProc(processors, encoding, false);
return iconv_convert<char>(processor, ucs4str, ls);
}
char ucs4_to_eightbit(char_type ucs4, string const & encoding)
{
map<string, IconvProcessor> & processors(ucs4To8bitProcessors());
map<string, IconvProcessor>::iterator it = processors.find(encoding);
if (it == processors.end()) {
IconvProcessor processor(encoding.c_str(), ucs4_codeset);
it = processors.insert(make_pair(encoding, processor)).first;
}
IconvProcessor & processor = getProc(processors, encoding, false);
char out;
int const bytes = it->second.convert((char *)(&ucs4), 4, &out, 1);
int const bytes = processor.convert((char *)(&ucs4), 4, &out, 1);
if (bytes > 0)
return out;
return 0;
@ -399,14 +348,9 @@ void ucs4_to_multibytes(char_type ucs4, vector<char> & out,
if (!static_processors.hasLocalData())
static_processors.setLocalData(new map<string, IconvProcessor>);
map<string, IconvProcessor> & processors = *static_processors.localData();
map<string, IconvProcessor>::iterator it = processors.find(encoding);
if (it == processors.end()) {
IconvProcessor processor(encoding.c_str(), ucs4_codeset);
it = processors.insert(make_pair(encoding, processor)).first;
}
IconvProcessor & processor = getProc(processors, encoding, false);
out.resize(4);
int bytes = it->second.convert((char *)(&ucs4), 4, &out[0], 4);
int bytes = processor.convert((char *)(&ucs4), 4, &out[0], 4);
if (bytes > 0)
out.resize(bytes);
else

View File

@ -1,3 +1,4 @@
// -*- C++ -*-
/**
* \file unicode.h
* This file is part of LyX, the document processor.
@ -14,8 +15,10 @@
#define LYX_SUPPORT_UNICODE_H
#include "support/strfwd.h"
#include "support/unique_ptr.h"
#include <cstddef>
#include <string>
#include <vector>
@ -44,32 +47,23 @@ namespace lyx {
*/
class IconvProcessor
{
/// open iconv.
/// \return true if the processor is ready to use.
bool init();
std::string const tocode_;
std::string const fromcode_;
struct Handler;
unique_ptr<Handler> h_;
public:
IconvProcessor(char const * tocode = "", char const * fromcode = "");
/// copy constructor needed because of pimpl_
IconvProcessor(IconvProcessor const &);
/// assignment operator needed because of pimpl_
IconvProcessor & operator=(IconvProcessor const &);
/// destructor
~IconvProcessor();
IconvProcessor(std::string tocode, std::string fromcode);
/// convert any data from \c fromcode to \c tocode unicode format.
/// \return the number of bytes of the converted output buffer.
int convert(char const * in_buffer, size_t in_size,
char * out_buffer, size_t max_out_size);
/// source encoding
std::string from() const;
/// target encoding
std::string to() const;
private:
/// open iconv.
/// \return true if the processor is ready to use.
bool init();
/// hide internals
class Impl;
Impl * pimpl_;
std::string to() const { return tocode_; }
// required by g++ 4.7
IconvProcessor(IconvProcessor &&) = default;
};
/// Get the global IconvProcessor instance of the current thread for