lyx_mirror/src/support/docstring.C
Enrico Forestieri 1a7aec0731 Improve the num_get locale facet
* src/support/docstring.C
	(do_get): use reserve() and the += operator in order to
	avoid a possible buffer overrun.


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@16070 a592a061-630c-0410-9148-cb99ea01b6c8
2006-11-27 01:52:26 +00:00

501 lines
13 KiB
C

/**
* \file docstring.C
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author Georg Baum
*
* Full author contact details are available in file CREDITS.
*/
#include <config.h>
#include "docstring.h"
#include "unicode.h"
#include <locale>
#include <iostream>
#include <boost/assert.hpp>
namespace lyx {
docstring const from_ascii(char const * ascii)
{
docstring s;
for (char const * c = ascii; *c; ++c) {
BOOST_ASSERT(static_cast<unsigned char>(*c) < 0x80);
s.push_back(*c);
}
return s;
}
docstring const from_ascii(std::string const & ascii)
{
int const len = ascii.length();
for (int i = 0; i < len; ++i)
BOOST_ASSERT(static_cast<unsigned char>(ascii[i]) < 0x80);
return docstring(ascii.begin(), ascii.end());
}
std::string const to_ascii(docstring const & ucs4)
{
int const len = ucs4.length();
std::string ascii;
ascii.resize(len);
for (int i = 0; i < len; ++i) {
BOOST_ASSERT(ucs4[i] < 0x80);
ascii[i] = static_cast<char>(ucs4[i]);
}
return ascii;
}
void utf8_to_ucs4(std::string const & utf8, docstring & ucs4)
{
size_t n = utf8.size();
// as utf8 is a multi-byte encoding, there would be at most
// n characters:
ucs4.resize(n);
if (n == 0)
return;
int maxoutsize = n * 4;
// basic_string::data() is not recognized by some old gcc version
// so we use &(ucs4[0]) instead.
char * outbuf = (char *)(&(ucs4[0]));
int bytes = utf8ToUcs4().convert(utf8.c_str(), n, outbuf, maxoutsize);
// adjust to the real converted size
ucs4.resize(bytes/4);
}
docstring const from_utf8(std::string const & utf8)
{
docstring ucs4;
utf8_to_ucs4(utf8, ucs4);
return ucs4;
}
std::string const to_utf8(docstring const & ucs4)
{
std::vector<char> const utf8 =
ucs4_to_utf8(ucs4.data(), ucs4.size());
return std::string(utf8.begin(), utf8.end());
}
bool operator==(lyx::docstring const & l, char const * r)
{
int const len = l.length();
for (int i = 0; i < len; ++i) {
BOOST_ASSERT(static_cast<unsigned char>(r[i]) < 0x80);
if (!r[i])
return false;
if (l[i] != lyx::docstring::value_type(r[i]))
return false;
}
return r[len] == '\0';
}
lyx::docstring operator+(lyx::docstring const & l, char const * r)
{
lyx::docstring s(l);
for (char const * c = r; *c; ++c) {
BOOST_ASSERT(static_cast<unsigned char>(*c) < 0x80);
s.push_back(*c);
}
return s;
}
lyx::docstring operator+(char const * l, lyx::docstring const & r)
{
lyx::docstring s;
for (char const * c = l; *c; ++c) {
BOOST_ASSERT(static_cast<unsigned char>(*c) < 0x80);
s.push_back(*c);
}
s += r;
return s;
}
lyx::docstring operator+(lyx::docstring const & l, char r)
{
BOOST_ASSERT(static_cast<unsigned char>(r) < 0x80);
return l + lyx::docstring::value_type(r);
}
lyx::docstring operator+(char l, lyx::docstring const & r)
{
BOOST_ASSERT(static_cast<unsigned char>(l) < 0x80);
return lyx::docstring::value_type(l) + r;
}
lyx::docstring & operator+=(lyx::docstring & l, char const * r)
{
for (char const * c = r; *c; ++c) {
BOOST_ASSERT(static_cast<unsigned char>(*c) < 0x80);
l.push_back(*c);
}
return l;
}
lyx::docstring & operator+=(lyx::docstring & l, char r)
{
BOOST_ASSERT(static_cast<unsigned char>(r) < 0x80);
l.push_back(r);
return l;
}
} // namespace lyx
#if (!defined(HAVE_WCHAR_T) || SIZEOF_WCHAR_T != 4) && defined(__GNUC__)
// gcc does not have proper locale facets for lyx::char_type if
// sizeof(wchar_t) == 2, so we have to implement them on our own.
// We get undefined references to these virtual methods. This looks like
// a bug in gcc. The implementation here does not do anything useful, since
// it is overriden in ascii_ctype_facet.
namespace std {
template<> ctype<lyx::char_type>::~ctype() {}
template<> bool
ctype<lyx::char_type>::do_is(ctype<lyx::char_type>::mask, lyx::char_type) const { return false; }
template<> lyx::char_type const *
ctype<lyx::char_type>::do_is(const lyx::char_type *, const lyx::char_type *, ctype<lyx::char_type>::mask *) const { return 0; }
template<> const lyx::char_type *
ctype<lyx::char_type>::do_scan_is(ctype<lyx::char_type>::mask, const lyx::char_type *, const lyx::char_type *) const { return 0; }
template<> const lyx::char_type *
ctype<lyx::char_type>::do_scan_not(ctype<lyx::char_type>::mask, const lyx::char_type *, const lyx::char_type *) const { return 0; }
template<> lyx::char_type ctype<lyx::char_type>::do_toupper(lyx::char_type) const { return 0; }
template<> const lyx::char_type * ctype<lyx::char_type>::do_toupper(lyx::char_type *, lyx::char_type const *) const { return 0; }
template<> lyx::char_type ctype<lyx::char_type>::do_tolower(lyx::char_type) const { return 0; }
template<> const lyx::char_type * ctype<lyx::char_type>::do_tolower(lyx::char_type *, lyx::char_type const *) const { return 0; }
template<> lyx::char_type ctype<lyx::char_type>::do_widen(char) const { return 0; }
template<> const char *
ctype<lyx::char_type>::do_widen(const char *, const char *, lyx::char_type *) const { return 0; }
template<> char
ctype<lyx::char_type>::do_narrow(const lyx::char_type, char) const { return 0; }
template<> const lyx::char_type *
ctype<lyx::char_type>::do_narrow(const lyx::char_type *, const lyx::char_type *, char, char *) const { return 0; }
}
namespace lyx {
class ctype_failure : public std::bad_cast {
public:
ctype_failure() throw() : std::bad_cast() {}
virtual ~ctype_failure() throw() {}
virtual const char* what() const throw()
{
return "The ctype<lyx::char_type> locale facet does only support ASCII characters on this platform.";
}
};
class num_put_failure : public std::bad_cast {
public:
num_put_failure() throw() : std::bad_cast() {}
virtual ~num_put_failure() throw() {}
virtual const char* what() const throw()
{
return "The num_put locale facet does only support ASCII characters on this platform.";
}
};
/// ctype facet for UCS4 characters. The implementation does only support pure
/// ASCII, since we do not need anything else for now.
/// The code is partly stolen from std::ctype<wchar_t> from gcc.
class ascii_ctype_facet : public std::ctype<lyx::char_type>
{
public:
typedef lyx::char_type char_type;
typedef wctype_t wmask_type;
explicit ascii_ctype_facet(size_t refs = 0) : std::ctype<char_type>(refs)
{
M_initialize_ctype();
}
protected:
bool M_narrow_ok;
char M_narrow[128];
wint_t M_widen[1 + static_cast<unsigned char>(-1)];
mask M_bit[16];
wmask_type M_wmask[16];
wmask_type M_convert_to_wmask(const mask m) const
{
wmask_type ret;
switch (m) {
case space: ret = wctype("space"); break;
case print: ret = wctype("print"); break;
case cntrl: ret = wctype("cntrl"); break;
case upper: ret = wctype("upper"); break;
case lower: ret = wctype("lower"); break;
case alpha: ret = wctype("alpha"); break;
case digit: ret = wctype("digit"); break;
case punct: ret = wctype("punct"); break;
case xdigit: ret = wctype("xdigit"); break;
case alnum: ret = wctype("alnum"); break;
case graph: ret = wctype("graph"); break;
default: ret = wmask_type();
}
return ret;
}
void M_initialize_ctype()
{
wint_t i;
for (i = 0; i < 128; ++i) {
const int c = wctob(i);
if (c == EOF)
break;
else
M_narrow[i] = static_cast<char>(c);
}
if (i == 128)
M_narrow_ok = true;
else
M_narrow_ok = false;
for (size_t i = 0; i < sizeof(M_widen) / sizeof(wint_t); ++i)
M_widen[i] = btowc(i);
for (size_t i = 0; i <= 15; ++i) {
M_bit[i] = static_cast<mask>(1 << i);
M_wmask[i] = M_convert_to_wmask(M_bit[i]);
}
}
virtual ~ascii_ctype_facet() {}
char_type do_toupper(char_type c) const
{
if (c >= 0x80)
throw ctype_failure();
return toupper(static_cast<int>(c));
}
char_type const * do_toupper(char_type * lo, char_type const * hi) const
{
while (lo < hi) {
if (*lo >= 0x80)
throw ctype_failure();
*lo = toupper(static_cast<int>(*lo));
++lo;
}
return hi;
}
char_type do_tolower(char_type c) const
{
if (c >= 0x80)
throw ctype_failure();
return tolower(c);
}
char_type const * do_tolower(char_type * lo, char_type const * hi) const
{
while (lo < hi) {
if (*lo >= 0x80)
throw ctype_failure();
*lo = tolower(*lo);
++lo;
}
return hi;
}
bool do_is(mask m, char_type c) const
{
if (c >= 0x80)
throw ctype_failure();
// The code below works because c is in the ASCII range.
// We could not use iswctype() which is designed for a 2byte
// whar_t without encoding conversion otherwise.
bool ret = false;
// Generically, 15 (instead of 10) since we don't know the numerical
// encoding of the various categories in /usr/include/ctype.h.
const size_t bitmasksize = 15;
for (size_t bitcur = 0; bitcur <= bitmasksize; ++bitcur)
if (m & M_bit[bitcur] &&
iswctype(static_cast<int>(c), M_wmask[bitcur])) {
ret = true;
break;
}
return ret;
}
char_type const * do_is(char_type const * lo, char_type const * hi, mask * vec) const
{
for (;lo < hi; ++vec, ++lo) {
if (*lo >= 0x80)
throw ctype_failure();
// The code below works because c is in the ASCII range.
// We could not use iswctype() which is designed for a 2byte
// whar_t without encoding conversion otherwise.
// Generically, 15 (instead of 10) since we don't know the numerical
// encoding of the various categories in /usr/include/ctype.h.
const size_t bitmasksize = 15;
mask m = 0;
for (size_t bitcur = 0; bitcur <= bitmasksize; ++bitcur)
if (iswctype(static_cast<int>(*lo), M_wmask[bitcur]))
m |= M_bit[bitcur];
*vec = m;
}
return hi;
}
char_type const * do_scan_is(mask m, char_type const * lo, char_type const * hi) const
{
while (lo < hi && !this->do_is(m, *lo))
++lo;
return lo;
}
char_type const * do_scan_not(mask m, char_type const * lo, char_type const * hi) const
{
while (lo < hi && this->do_is(m, *lo) != 0)
++lo;
return lo;
}
char_type do_widen(char c) const
{
if (static_cast<unsigned char>(c) < 0x80)
return c;
throw ctype_failure();
}
const char* do_widen(const char* lo, const char* hi, char_type* dest) const
{
while (lo < hi) {
if (static_cast<unsigned char>(*lo) >= 0x80)
throw ctype_failure();
*dest = *lo;
++lo;
++dest;
}
return hi;
}
char do_narrow(char_type wc, char) const
{
if (wc < 0x80)
return static_cast<char>(wc);
throw ctype_failure();
}
const char_type * do_narrow(const char_type * lo, const char_type * hi, char, char * dest) const
{
while (lo < hi) {
if (*lo < 0x80)
*dest = static_cast<char>(*lo);
else
throw ctype_failure();
++lo;
++dest;
}
return hi;
}
};
/// Facet for outputting numbers to odocstreams as ascii.
/// Here we simply need defining the virtual do_put functions.
class ascii_num_put_facet : public std::num_put<lyx::char_type, std::ostreambuf_iterator<lyx::char_type, std::char_traits<lyx::char_type> > >
{
typedef std::ostreambuf_iterator<lyx::char_type, std::char_traits<lyx::char_type> > iter_type;
public:
ascii_num_put_facet(size_t refs = 0) : std::num_put<lyx::char_type, iter_type>(refs) {}
/// Facet for converting numbers to ascii strings.
class string_num_put_facet : public std::num_put<char, std::basic_string<char>::iterator>
{
public:
string_num_put_facet() : std::num_put<char, std::basic_string<char>::iterator>(1) {}
};
protected:
iter_type
do_put(iter_type oit, std::ios_base & b, char_type fill, long v) const
{
if (fill >= 0x80)
throw num_put_failure();
std::string s;
// 64 is large enough
s.resize(64);
string_num_put_facet f;
std::string::const_iterator cit = s.begin();
std::string::const_iterator end =
f.put(s.begin(), b, fill, v);
for (; cit != end; ++cit, ++oit)
*oit = *cit;
return oit;
}
};
/// Facet for inputting ascii representations of numbers from idocstreams.
/// Here we simply need defining the virtual do_get functions.
class ascii_num_get_facet : public std::num_get<lyx::char_type, std::istreambuf_iterator<lyx::char_type, std::char_traits<lyx::char_type> > >
{
typedef std::istreambuf_iterator<lyx::char_type, std::char_traits<lyx::char_type> > iter_type;
public:
ascii_num_get_facet(size_t refs = 0) : std::num_get<lyx::char_type, iter_type>(refs) {}
/// Facet for converting ascii representation of numbers to a value.
class string_num_get_facet : public std::num_get<char, std::basic_string<char>::iterator>
{
public:
string_num_get_facet() : std::num_get<char, std::basic_string<char>::iterator>(1) {}
};
private:
bool isNumpunct(lyx::char_type const c) const
{
/// Only account for the standard numpunct "C" locale facet.
return c < 0x80 && (c == '-' || c == '+' || isdigit(c)
|| ('a' <= c && c <= 'f') || ('A' <= c && c <= 'F')
|| c == 'x' || c == 'X');
}
protected:
iter_type
do_get(iter_type iit, iter_type eit, std::ios_base & b,
std::ios_base::iostate & err, long & v) const
{
std::string s;
s.reserve(64);
for (; iit != eit && isNumpunct(*iit); ++iit)
s += static_cast<char>(*iit);
string_num_get_facet f;
f.get(s.begin(), s.end(), b, err, v);
return iit;
}
};
/// class to add our facets to the global locale
class locale_initializer {
public:
locale_initializer()
{
std::locale global;
std::locale const loc1(global, new ascii_ctype_facet);
std::locale const loc2(loc1, new ascii_num_put_facet);
std::locale const loc3(loc2, new ascii_num_get_facet);
std::locale::global(loc3);
}
};
namespace {
/// make sure that our facets get used
static locale_initializer initializer;
}
}
#endif