[9231] Update used utf8 cpp library version up to 2.2.4

This commit is contained in:
VladimirMangos 2010-01-21 21:41:21 +03:00
parent cee525f9c8
commit 6653539a5e
6 changed files with 311 additions and 177 deletions

View file

@ -1,9 +1,9 @@
utf8 cpp library
Release 2.1
Release 2.2.4
This is a minor feature release - added the function peek_next.
This is a minor bug fix release that improves converting from utf-16 to utf-8 error detection.
Changes from version 2.o
- Implemented feature request [ 1770746 ] "Provide a const version of next() (some sort of a peek() )
Changes from version 2.2.3
- Bug fix [2857454] dereference invalid iterator when lead surrogate was last element of the string.
Files included in the release: utf8.h, core.h, checked.h, unchecked.h, utf8cpp.html, ReleaseNotes

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@ -57,6 +57,16 @@
</li>
<li>
<a href="#examples">Examples of Use</a>
<ul class="toc">
<li>
<a href=#introsample>Introductionary Sample </a>
</li>
<li>
<a href=#validfile>Checking if a file contains valid UTF-8 text</a>
</li>
<li>
<a href=#fixinvalid>Ensure that a string contains valid UTF-8 text</a>
</li>
</li>
<li>
<a href="#reference">Reference</a>
@ -91,14 +101,14 @@
</h2>
<p>
Many C++ developers miss an easy and portable way of handling Unicode encoded
strings. C++ Standard is currently Unicode agnostic, and while some work is being
done to introduce Unicode to the next incarnation called C++0x, for the moment
nothing of the sort is available. In the meantime, developers use 3rd party
libraries like ICU, OS specific capabilities, or simply roll out their own
solutions.
strings. The original C++ Standard (known as C++98 or C++03) is Unicode agnostic,
and while some work is being done to introduce Unicode to the next incarnation
called C++0x, for the moment nothing of the sort is available. In the meantime,
developers use third party libraries like ICU, OS specific capabilities, or simply
roll out their own solutions.
</p>
<p>
In order to easily handle UTF-8 encoded Unicode strings, I have come up with a small
In order to easily handle UTF-8 encoded Unicode strings, I came up with a small
generic library. For anybody used to work with STL algorithms and iterators, it should be
easy and natural to use. The code is freely available for any purpose - check out
the license at the beginning of the utf8.h file. If you run into
@ -115,11 +125,13 @@
<h2 id="examples">
Examples of use
</h2>
<h3 id="introsample">
Introductionary Sample
</h3>
<p>
To illustrate the use of this utf8 library, we shall open a file containing UTF-8
encoded text, check whether it starts with a byte order mark, read each line into a
<code>std::string</code>, check it for validity, convert the text to UTF-16, and
back to UTF-8:
To illustrate the use of the library, let's start with a small but complete program
that opens a file containing UTF-8 encoded text, reads it line by line, checks each line
for invalid UTF-8 byte sequences, and converts it to UTF-16 encoding and back to UTF-8:
</p>
<pre>
<span class="preprocessor">#include &lt;fstream&gt;</span>
@ -128,33 +140,26 @@
<span class="preprocessor">#include &lt;vector&gt;</span>
<span class="preprocessor">#include "utf8.h"</span>
<span class="keyword">using namespace</span> std;
<span class="keyword">int</span> main()
<span class="keyword">int</span> main(<span class="keyword">int</span> argc, <span class="keyword">char</span>** argv)
{
<span class="keyword">if</span> (argc != <span class="literal">2</span>) {
cout &lt;&lt; <span class="literal">"\nUsage: docsample filename\n"</span>;
<span class="keyword">return</span> <span class="literal">0</span>;
}
<span class="keyword">const char</span>* test_file_path = argv[1];
<span class="comment">// Open the test file (must be UTF-8 encoded)</span>
<span class="comment">// Open the test file (contains UTF-8 encoded text)</span>
ifstream fs8(test_file_path);
<span class="keyword">if</span> (!fs8.is_open()) {
cout &lt;&lt; <span class=
"literal">"Could not open "</span> &lt;&lt; test_file_path &lt;&lt; endl;
<span class="keyword">return</span> <span class="literal">0</span>;
}
<span class="comment">// Read the first line of the file</span>
<span class="keyword">unsigned</span> line_count = <span class="literal">1</span>;
string line;
<span class="keyword">if</span> (!getline(fs8, line))
<span class="keyword">return</span> <span class="literal">0</span>;
<span class="comment">// Look for utf-8 byte-order mark at the beginning</span>
<span class="keyword">if</span> (line.size() &gt; <span class="literal">2</span>) {
<span class="keyword">if</span> (utf8::is_bom(line.c_str()))
cout &lt;&lt; <span class=
"literal">"There is a byte order mark at the beginning of the file\n"</span>;
}
<span class="comment">// Play with all the lines in the file</span>
<span class="keyword">do</span> {
<span class="keyword">while</span> (getline(fs8, line)) {
<span class="comment">// check for invalid utf-8 (for a simple yes/no check, there is also utf8::is_valid function)</span>
string::iterator end_it = utf8::find_invalid(line.begin(), line.end());
<span class="keyword">if</span> (end_it != line.end()) {
@ -165,37 +170,87 @@
"literal">"This part is fine: "</span> &lt;&lt; string(line.begin(), end_it) &lt;&lt; <span
class="literal">"\n"</span>;
}
<span class="comment">// Get the line length (at least for the valid part)</span>
<span class="keyword">int</span> length = utf8::distance(line.begin(), end_it);
cout &lt;&lt; <span class=
"literal">"Length of line "</span> &lt;&lt; line_count &lt;&lt; <span class=
"literal">" is "</span> &lt;&lt; length &lt;&lt; <span class="literal">"\n"</span>;
<span class="comment">// Convert it to utf-16</span>
vector&lt;unsigned short&gt; utf16line;
utf8::utf8to16(line.begin(), end_it, back_inserter(utf16line));
<span class="comment">// And back to utf-8</span>
string utf8line;
utf8::utf16to8(utf16line.begin(), utf16line.end(), back_inserter(utf8line));
<span class="comment">// Confirm that the conversion went OK:</span>
<span class="keyword">if</span> (utf8line != string(line.begin(), end_it))
cout &lt;&lt; <span class=
"literal">"Error in UTF-16 conversion at line: "</span> &lt;&lt; line_count &lt;&lt; <span
class="literal">"\n"</span>;
getline(fs8, line);
line_count++;
} <span class="keyword">while</span> (!fs8.eof());
}
<span class="keyword">return</span> <span class="literal">0</span>;
}
</pre>
<p>
In the previous code sample, we have seen the use of the following functions from
<code>utf8</code> namespace: first we used <code>is_bom</code> function to detect
UTF-8 byte order mark at the beginning of the file; then for each line we performed
In the previous code sample, for each line we performed
a detection of invalid UTF-8 sequences with <code>find_invalid</code>; the number
of characters (more precisely - the number of Unicode code points) in each line was
of characters (more precisely - the number of Unicode code points, including the end
of line and even BOM if there is one) in each line was
determined with a use of <code>utf8::distance</code>; finally, we have converted
each line to UTF-16 encoding with <code>utf8to16</code> and back to UTF-8 with
<code>utf16to8</code>.
</p>
<h3 id="validfile">Checking if a file contains valid UTF-8 text</h3>
<p>
Here is a function that checks whether the content of a file is valid UTF-8 encoded text without
reading the content into the memory:
</p>
<pre>
<span class="keyword">bool</span> valid_utf8_file(i<span class="keyword">const char</span>* file_name)
{
ifstream ifs(file_name);
<span class="keyword">if</span> (!ifs)
<span class="keyword">return false</span>; <span class="comment">// even better, throw here</span>
istreambuf_iterator&lt;<span class="keyword">char</span>&gt; it(ifs.rdbuf());
istreambuf_iterator&lt;<span class="keyword">char</span>&gt; eos;
<span class="keyword">return</span> utf8::is_valid(it, eos);
}
</pre>
<p>
Because the function <code>utf8::is_valid()</code> works with input iterators, we were able
to pass an <code>istreambuf_iterator</code> to it and read the content of the file directly
without loading it to the memory first.</p>
<p>
Note that other functions that take input iterator arguments can be used in a similar way. For
instance, to read the content of a UTF-8 encoded text file and convert the text to UTF-16, just
do something like:
</p>
<pre>
utf8::utf8to16(it, eos, back_inserter(u16string));
</pre>
<h3 id="fixinvalid">Ensure that a string contains valid UTF-8 text</h3>
<p>
If we have some text that "probably" contains UTF-8 encoded text and we want to
replace any invalid UTF-8 sequence with a replacement character, something like
the following function may be used:
</p>
<pre>
<span class="keyword">void</span> fix_utf8_string(std::string&amp; str)
{
std::string temp;
utf8::replace_invalid(str.begin(), str.end(), back_inserter(temp));
str = temp;
}
</pre>
<p>The function will replace any invalid UTF-8 sequence with a Unicode replacement character.
There is an overloaded function that enables the caller to supply their own replacement character.
</p>
<h2 id="reference">
Reference

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@ -72,7 +72,7 @@ namespace utf8
octet_iterator sequence_start = start;
internal::utf_error err_code = internal::validate_next(start, end);
switch (err_code) {
case internal::OK :
case internal::UTF8_OK :
for (octet_iterator it = sequence_start; it != start; ++it)
*out++ = *it;
break;
@ -120,15 +120,12 @@ namespace utf8
*(result++) = static_cast<uint8_t>(((cp >> 6) & 0x3f) | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else if (cp <= internal::CODE_POINT_MAX) { // four octets
else { // four octets
*(result++) = static_cast<uint8_t>((cp >> 18) | 0xf0);
*(result++) = static_cast<uint8_t>(((cp >> 12) & 0x3f) | 0x80);
*(result++) = static_cast<uint8_t>(((cp >> 6) & 0x3f) | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else
throw invalid_code_point(cp);
return result;
}
@ -138,7 +135,7 @@ namespace utf8
uint32_t cp = 0;
internal::utf_error err_code = internal::validate_next(it, end, &cp);
switch (err_code) {
case internal::OK :
case internal::UTF8_OK :
break;
case internal::NOT_ENOUGH_ROOM :
throw not_enough_room();
@ -204,18 +201,22 @@ namespace utf8
while (start != end) {
uint32_t cp = internal::mask16(*start++);
// Take care of surrogate pairs first
if (internal::is_surrogate(cp)) {
if (internal::is_lead_surrogate(cp)) {
if (start != end) {
uint32_t trail_surrogate = internal::mask16(*start++);
if (trail_surrogate >= internal::TRAIL_SURROGATE_MIN && trail_surrogate <= internal::TRAIL_SURROGATE_MAX)
if (internal::is_trail_surrogate(trail_surrogate))
cp = (cp << 10) + trail_surrogate + internal::SURROGATE_OFFSET;
else
throw invalid_utf16(static_cast<uint16_t>(trail_surrogate));
}
else
throw invalid_utf16(static_cast<uint16_t>(*start));
throw invalid_utf16(static_cast<uint16_t>(cp));
}
// Lone trail surrogate
else if (internal::is_trail_surrogate(cp))
throw invalid_utf16(static_cast<uint16_t>(cp));
result = append(cp, result);
}
return result;

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@ -30,23 +30,14 @@ DEALINGS IN THE SOFTWARE.
#include <iterator>
// use MaNGOS core types
#include "Platform/Define.h"
namespace utf8
{
// The typedefs for 8-bit, 16-bit and 32-bit unsigned integers
// You may need to change them to match your system.
// These typedefs have the same names as ones from cstdint, or boost/cstdint
/* use MaNGOS alternatives
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;
*/
typedef uint8 uint8_t;
typedef uint16 uint16_t;
typedef uint32 uint32_t;
// Helper code - not intended to be directly called by the library users. May be changed at any time
namespace internal
@ -80,6 +71,18 @@ namespace internal
return ((mask8(oc) >> 6) == 0x2);
}
template <typename u16>
inline bool is_lead_surrogate(u16 cp)
{
return (cp >= LEAD_SURROGATE_MIN && cp <= LEAD_SURROGATE_MAX);
}
template <typename u16>
inline bool is_trail_surrogate(u16 cp)
{
return (cp >= TRAIL_SURROGATE_MIN && cp <= TRAIL_SURROGATE_MAX);
}
template <typename u16>
inline bool is_surrogate(u16 cp)
{
@ -109,117 +112,192 @@ namespace internal
return 0;
}
enum utf_error {OK, NOT_ENOUGH_ROOM, INVALID_LEAD, INCOMPLETE_SEQUENCE, OVERLONG_SEQUENCE, INVALID_CODE_POINT};
inline bool is_overlong_sequence(uint32_t cp, int length)
{
if (cp < 0x80) {
if (length != 1)
return true;
}
else if (cp < 0x800) {
if (length != 2)
return true;
}
else if (cp < 0x10000) {
if (length != 3)
return true;
}
return false;
}
enum utf_error {UTF8_OK, NOT_ENOUGH_ROOM, INVALID_LEAD, INCOMPLETE_SEQUENCE, OVERLONG_SEQUENCE, INVALID_CODE_POINT};
/// get_sequence_x functions decode utf-8 sequences of the length x
template <typename octet_iterator>
utf_error get_sequence_1(octet_iterator& it, octet_iterator end, uint32_t* code_point)
{
if (it != end) {
if (code_point)
*code_point = mask8(*it);
return UTF8_OK;
}
return NOT_ENOUGH_ROOM;
}
template <typename octet_iterator>
utf_error get_sequence_2(octet_iterator& it, octet_iterator end, uint32_t* code_point)
{
utf_error ret_code = NOT_ENOUGH_ROOM;
if (it != end) {
uint32_t cp = mask8(*it);
if (++it != end) {
if (is_trail(*it)) {
cp = ((cp << 6) & 0x7ff) + ((*it) & 0x3f);
if (code_point)
*code_point = cp;
ret_code = UTF8_OK;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
return ret_code;
}
template <typename octet_iterator>
utf_error get_sequence_3(octet_iterator& it, octet_iterator end, uint32_t* code_point)
{
utf_error ret_code = NOT_ENOUGH_ROOM;
if (it != end) {
uint32_t cp = mask8(*it);
if (++it != end) {
if (is_trail(*it)) {
cp = ((cp << 12) & 0xffff) + ((mask8(*it) << 6) & 0xfff);
if (++it != end) {
if (is_trail(*it)) {
cp += (*it) & 0x3f;
if (code_point)
*code_point = cp;
ret_code = UTF8_OK;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
return ret_code;
}
template <typename octet_iterator>
utf_error get_sequence_4(octet_iterator& it, octet_iterator end, uint32_t* code_point)
{
utf_error ret_code = NOT_ENOUGH_ROOM;
if (it != end) {
uint32_t cp = mask8(*it);
if (++it != end) {
if (is_trail(*it)) {
cp = ((cp << 18) & 0x1fffff) + ((mask8(*it) << 12) & 0x3ffff);
if (++it != end) {
if (is_trail(*it)) {
cp += (mask8(*it) << 6) & 0xfff;
if (++it != end) {
if (is_trail(*it)) {
cp += (*it) & 0x3f;
if (code_point)
*code_point = cp;
ret_code = UTF8_OK;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
else
ret_code = INCOMPLETE_SEQUENCE;
}
else
ret_code = NOT_ENOUGH_ROOM;
}
return ret_code;
}
template <typename octet_iterator>
utf_error validate_next(octet_iterator& it, octet_iterator end, uint32_t* code_point)
{
uint32_t cp = mask8(*it);
// Check the lead octet
// Save the original value of it so we can go back in case of failure
// Of course, it does not make much sense with i.e. stream iterators
octet_iterator original_it = it;
uint32_t cp = 0;
// Determine the sequence length based on the lead octet
typedef typename std::iterator_traits<octet_iterator>::difference_type octet_difference_type;
octet_difference_type length = sequence_length(it);
// "Shortcut" for ASCII characters
if (length == 1) {
if (end - it > 0) {
if (code_point)
*code_point = cp;
++it;
return OK;
}
else
return NOT_ENOUGH_ROOM;
}
// Do we have enough memory?
if (std::distance(it, end) < length)
return NOT_ENOUGH_ROOM;
// Check trail octets and calculate the code point
switch (length) {
case 0:
if (length == 0)
return INVALID_LEAD;
// Now that we have a valid sequence length, get trail octets and calculate the code point
utf_error err = UTF8_OK;
switch (length) {
case 1:
err = get_sequence_1(it, end, &cp);
break;
case 2:
if (is_trail(*(++it))) {
cp = ((cp << 6) & 0x7ff) + ((*it) & 0x3f);
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
err = get_sequence_2(it, end, &cp);
break;
case 3:
if (is_trail(*(++it))) {
cp = ((cp << 12) & 0xffff) + ((mask8(*it) << 6) & 0xfff);
if (is_trail(*(++it))) {
cp += (*it) & 0x3f;
}
else {
std::advance(it, -2);
return INCOMPLETE_SEQUENCE;
}
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
err = get_sequence_3(it, end, &cp);
break;
case 4:
if (is_trail(*(++it))) {
cp = ((cp << 18) & 0x1fffff) + ((mask8(*it) << 12) & 0x3ffff);
if (is_trail(*(++it))) {
cp += (mask8(*it) << 6) & 0xfff;
if (is_trail(*(++it))) {
cp += (*it) & 0x3f;
}
else {
std::advance(it, -3);
return INCOMPLETE_SEQUENCE;
}
}
else {
std::advance(it, -2);
return INCOMPLETE_SEQUENCE;
}
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
err = get_sequence_4(it, end, &cp);
break;
}
// Is the code point valid?
if (!is_code_point_valid(cp)) {
for (octet_difference_type i = 0; i < length - 1; ++i)
--it;
return INVALID_CODE_POINT;
}
if (err == UTF8_OK) {
// Decoding succeeded. Now, security checks...
if (is_code_point_valid(cp)) {
if (!is_overlong_sequence(cp, length)){
// Passed! Return here.
if (code_point)
*code_point = cp;
if (cp < 0x80) {
if (length != 1) {
std::advance(it, -(length-1));
return OVERLONG_SEQUENCE;
}
}
else if (cp < 0x800) {
if (length != 2) {
std::advance(it, -(length-1));
return OVERLONG_SEQUENCE;
}
}
else if (cp < 0x10000) {
if (length != 3) {
std::advance(it, -(length-1));
return OVERLONG_SEQUENCE;
}
}
++it;
return OK;
return UTF8_OK;
}
else
err = OVERLONG_SEQUENCE;
}
else
err = INVALID_CODE_POINT;
}
// Failure branch - restore the original value of the iterator
it = original_it;
return err;
}
template <typename octet_iterator>
@ -240,7 +318,7 @@ namespace internal
octet_iterator result = start;
while (result != end) {
internal::utf_error err_code = internal::validate_next(result, end);
if (err_code != internal::OK)
if (err_code != internal::UTF8_OK)
return result;
}
return result;

View file

@ -45,13 +45,13 @@ namespace utf8
}
else if (cp < 0x10000) { // three octets
*(result++) = static_cast<uint8_t>((cp >> 12) | 0xe0);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>(((cp >> 6) & 0x3f) | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else { // four octets
*(result++) = static_cast<uint8_t>((cp >> 18) | 0xf0);
*(result++) = static_cast<uint8_t>((cp >> 12)& 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>(((cp >> 12) & 0x3f)| 0x80);
*(result++) = static_cast<uint8_t>(((cp >> 6) & 0x3f) | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
return result;
@ -132,7 +132,7 @@ namespace utf8
while (start != end) {
uint32_t cp = internal::mask16(*start++);
// Take care of surrogate pairs first
if (internal::is_surrogate(cp)) {
if (internal::is_lead_surrogate(cp)) {
uint32_t trail_surrogate = internal::mask16(*start++);
cp = (cp << 10) + trail_surrogate + internal::SURROGATE_OFFSET;
}

View file

@ -1,4 +1,4 @@
#ifndef __REVISION_NR_H__
#define __REVISION_NR_H__
#define REVISION_NR "9230"
#define REVISION_NR "9231"
#endif // __REVISION_NR_H__