mediawiki-extensions-Scribunto/includes/engines/LuaCommon/UstringLibrary.php
Kunal Mehta d245edbb94 Add phan configuration
Manually import LuaSandbox's git repository as a composer dependency to
provide the PHP stubs for phan.

Change-Id: I6226b9211f31d829da5a2775c6f5cf3599dd8ebc
2018-05-14 18:41:59 -07:00

782 lines
22 KiB
PHP
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This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?php
use UtfNormal\Validator;
// @codingStandardsIgnoreLine Squiz.Classes.ValidClassName.NotCamelCaps
class Scribunto_LuaUstringLibrary extends Scribunto_LuaLibraryBase {
/**
* Limit on pattern lengths, in bytes not characters
* @var integer
*/
private $patternLengthLimit = 10000;
/**
* Limit on string lengths, in bytes not characters
* If null, $wgMaxArticleSize * 1024 will be used
* @var integer|null
*/
private $stringLengthLimit = null;
/**
* PHP until 5.6.9 are buggy when the regex in preg_replace an
* preg_match_all matches the empty string.
* @var boolean
*/
private $phpBug53823 = false;
/**
* A cache of patterns and the regexes they generate.
* @var MapCacheLRU
*/
private $patternRegexCache = null;
function __construct( $engine ) {
if ( $this->stringLengthLimit === null ) {
global $wgMaxArticleSize;
$this->stringLengthLimit = $wgMaxArticleSize * 1024;
}
$this->phpBug53823 = preg_replace( '//us', 'x', "\xc3\xa1" ) === "x\xc3x\xa1x";
$this->patternRegexCache = new MapCacheLRU( 100 );
parent::__construct( $engine );
}
function register() {
$perf = $this->getEngine()->getPerformanceCharacteristics();
if ( $perf['phpCallsRequireSerialization'] ) {
$lib = [
// Pattern matching is still much faster in PHP, even with the
// overhead of serialization
'find' => [ $this, 'ustringFind' ],
'match' => [ $this, 'ustringMatch' ],
'gmatch_init' => [ $this, 'ustringGmatchInit' ],
'gmatch_callback' => [ $this, 'ustringGmatchCallback' ],
'gsub' => [ $this, 'ustringGsub' ],
];
} else {
$lib = [
'isutf8' => [ $this, 'ustringIsUtf8' ],
'byteoffset' => [ $this, 'ustringByteoffset' ],
'codepoint' => [ $this, 'ustringCodepoint' ],
'gcodepoint_init' => [ $this, 'ustringGcodepointInit' ],
'toNFC' => [ $this, 'ustringToNFC' ],
'toNFD' => [ $this, 'ustringToNFD' ],
'toNFKC' => [ $this, 'ustringToNFKC' ],
'toNFKD' => [ $this, 'ustringToNFKD' ],
'char' => [ $this, 'ustringChar' ],
'len' => [ $this, 'ustringLen' ],
'sub' => [ $this, 'ustringSub' ],
'upper' => [ $this, 'ustringUpper' ],
'lower' => [ $this, 'ustringLower' ],
'find' => [ $this, 'ustringFind' ],
'match' => [ $this, 'ustringMatch' ],
'gmatch_init' => [ $this, 'ustringGmatchInit' ],
'gmatch_callback' => [ $this, 'ustringGmatchCallback' ],
'gsub' => [ $this, 'ustringGsub' ],
];
}
return $this->getEngine()->registerInterface( 'mw.ustring.lua', $lib, [
'stringLengthLimit' => $this->stringLengthLimit,
'patternLengthLimit' => $this->patternLengthLimit,
] );
}
private function checkString( $name, $s, $checkEncoding = true ) {
if ( $this->getLuaType( $s ) == 'number' ) {
$s = (string)$s;
} else {
$this->checkType( $name, 1, $s, 'string' );
if ( $checkEncoding && !mb_check_encoding( $s, 'UTF-8' ) ) {
throw new Scribunto_LuaError( "bad argument #1 to '$name' (string is not UTF-8)" );
}
if ( strlen( $s ) > $this->stringLengthLimit ) {
throw new Scribunto_LuaError(
"bad argument #1 to '$name' (string is longer than $this->stringLengthLimit bytes)"
);
}
}
}
public function ustringIsUtf8( $s ) {
$this->checkString( 'isutf8', $s, false );
return [ mb_check_encoding( $s, 'UTF-8' ) ];
}
public function ustringByteoffset( $s, $l = 1, $i = 1 ) {
$this->checkString( 'byteoffset', $s );
$this->checkTypeOptional( 'byteoffset', 2, $l, 'number', 1 );
$this->checkTypeOptional( 'byteoffset', 3, $i, 'number', 1 );
$bytelen = strlen( $s );
if ( $i < 0 ) {
$i = $bytelen + $i + 1;
}
if ( $i < 1 || $i > $bytelen ) {
return [ null ];
}
$i--;
$j = $i;
while ( ( ord( $s[$i] ) & 0xc0 ) === 0x80 ) {
$i--;
}
if ( $l > 0 && $j === $i ) {
$l--;
}
$char = mb_strlen( substr( $s, 0, $i ), 'UTF-8' ) + $l;
if ( $char < 0 || $char >= mb_strlen( $s, 'UTF-8' ) ) {
return [ null ];
} else {
return [ strlen( mb_substr( $s, 0, $char, 'UTF-8' ) ) + 1 ];
}
}
public function ustringCodepoint( $s, $i = 1, $j = null ) {
$this->checkString( 'codepoint', $s );
$this->checkTypeOptional( 'codepoint', 2, $i, 'number', 1 );
$this->checkTypeOptional( 'codepoint', 3, $j, 'number', $i );
$l = mb_strlen( $s, 'UTF-8' );
if ( $i < 0 ) {
$i = $l + $i + 1;
}
if ( $j < 0 ) {
$j = $l + $j + 1;
}
if ( $j < $i ) {
return [];
}
$i = max( 1, min( $i, $l + 1 ) );
$j = max( 1, min( $j, $l + 1 ) );
$s = mb_substr( $s, $i - 1, $j - $i + 1, 'UTF-8' );
return unpack( 'N*', mb_convert_encoding( $s, 'UTF-32BE', 'UTF-8' ) );
}
public function ustringGcodepointInit( $s, $i = 1, $j = null ) {
return [ $this->ustringCodepoint( $s, $i, $j ) ];
}
public function ustringToNFC( $s ) {
$this->checkString( 'toNFC', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFC( $s ) ];
}
public function ustringToNFD( $s ) {
$this->checkString( 'toNFD', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFD( $s ) ];
}
public function ustringToNFKC( $s ) {
$this->checkString( 'toNFKC', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFKC( $s ) ];
}
public function ustringToNFKD( $s ) {
$this->checkString( 'toNFKD', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFKD( $s ) ];
}
/**
* @return array
*/
public function ustringChar() {
$args = func_get_args();
if ( count( $args ) > $this->stringLengthLimit ) {
throw new Scribunto_LuaError( "too many arguments to 'char'" );
}
foreach ( $args as $k => &$v ) {
if ( !is_numeric( $v ) ) {
$this->checkType( 'char', $k + 1, $v, 'number' );
}
$v = (int)floor( $v );
if ( $v < 0 || $v > 0x10ffff ) {
$k++;
throw new Scribunto_LuaError( "bad argument #$k to 'char' (value out of range)" );
}
}
array_unshift( $args, 'N*' );
$s = call_user_func_array( 'pack', $args );
$s = mb_convert_encoding( $s, 'UTF-8', 'UTF-32BE' );
if ( strlen( $s ) > $this->stringLengthLimit ) {
throw new Scribunto_LuaError( "result to long for 'char'" );
}
return [ $s ];
}
public function ustringLen( $s ) {
$this->checkString( 'len', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ mb_strlen( $s, 'UTF-8' ) ];
}
public function ustringSub( $s, $i=1, $j=-1 ) {
$this->checkString( 'sub', $s );
$this->checkTypeOptional( 'sub', 2, $i, 'number', 1 );
$this->checkTypeOptional( 'sub', 3, $j, 'number', -1 );
$len = mb_strlen( $s, 'UTF-8' );
if ( $i < 0 ) {
$i = $len + $i + 1;
}
if ( $j < 0 ) {
$j = $len + $j + 1;
}
if ( $j < $i ) {
return [ '' ];
}
$i = max( 1, min( $i, $len + 1 ) );
$j = max( 1, min( $j, $len + 1 ) );
$s = mb_substr( $s, $i - 1, $j - $i + 1, 'UTF-8' );
return [ $s ];
}
public function ustringUpper( $s ) {
$this->checkString( 'upper', $s );
return [ mb_strtoupper( $s, 'UTF-8' ) ];
}
public function ustringLower( $s ) {
$this->checkString( 'lower', $s );
return [ mb_strtolower( $s, 'UTF-8' ) ];
}
private function checkPattern( $name, $pattern ) {
if ( $this->getLuaType( $pattern ) == 'number' ) {
$pattern = (string)$pattern;
}
$this->checkType( $name, 2, $pattern, 'string' );
if ( !mb_check_encoding( $pattern, 'UTF-8' ) ) {
throw new Scribunto_LuaError( "bad argument #2 to '$name' (string is not UTF-8)" );
}
if ( strlen( $pattern ) > $this->patternLengthLimit ) {
throw new Scribunto_LuaError(
"bad argument #2 to '$name' (pattern is longer than $this->patternLengthLimit bytes)"
);
}
}
/* Convert a Lua pattern into a PCRE regex */
private function patternToRegex( $pattern, $anchor, $name ) {
$cacheKey = serialize( [ $pattern, $anchor ] );
if ( !$this->patternRegexCache->has( $cacheKey ) ) {
$this->checkPattern( $name, $pattern );
$pat = preg_split( '//us', $pattern, null, PREG_SPLIT_NO_EMPTY );
static $charsets = null, $brcharsets = null;
if ( $charsets === null ) {
$charsets = [
// If you change these, also change lualib/ustring/make-tables.php
// (and run it to regenerate charsets.lua)
'a' => '\p{L}',
'c' => '\p{Cc}',
'd' => '\p{Nd}',
'l' => '\p{Ll}',
'p' => '\p{P}',
's' => '\p{Xps}',
'u' => '\p{Lu}',
'w' => '[\p{L}\p{Nd}]',
'x' => '[0-9A-Fa-f---]',
'z' => '\0',
// These *must* be the inverse of the above
'A' => '\P{L}',
'C' => '\P{Cc}',
'D' => '\P{Nd}',
'L' => '\P{Ll}',
'P' => '\P{P}',
'S' => '\P{Xps}',
'U' => '\P{Lu}',
'W' => '[^\p{L}\p{Nd}]',
'X' => '[^0-9A-Fa-f---]',
'Z' => '[^\0]',
];
$brcharsets = [
'w' => '\p{L}\p{Nd}',
'x' => '0-9A-Fa-f---',
// Negated sets that are not expressable as a simple \P{} are
// unfortunately complicated.
// Xan is L plus N, so ^Xan plus Nl plus No is anything that's not L or Nd
'W' => '\P{Xan}\p{Nl}\p{No}',
// Manually constructed. Fun.
'X' => '\x00-\x2f\x3a-\x40\x47-\x60\x67-\x{ff0f}'
. '\x{ff1a}-\x{ff20}\x{ff27}-\x{ff40}\x{ff47}-\x{10ffff}',
// Ha!
'Z' => '\x01-\x{10ffff}',
] + $charsets;
}
$re = '/';
$len = count( $pat );
$capt = [];
$anypos = false;
$captparen = [];
$opencapt = [];
$bct = 0;
for ( $i = 0; $i < $len; $i++ ) {
$ii = $i + 1;
$q = false;
switch ( $pat[$i] ) {
case '^':
$q = $i;
$re .= ( $anchor === false || $q ) ? '\\^' : $anchor;
break;
case '$':
$q = ( $i < $len - 1 );
$re .= $q ? '\\$' : '$';
break;
case '(':
if ( $i + 1 >= $len ) {
throw new Scribunto_LuaError( "Unmatched open-paren at pattern character $ii" );
}
$n = count( $capt ) + 1;
$capt[$n] = ( $pat[$i + 1] === ')' );
if ( $capt[$n] ) {
$anypos = true;
}
$re .= "(?<m$n>";
$opencapt[] = $n;
$captparen[$n] = $ii;
break;
case ')':
if ( count( $opencapt ) <= 0 ) {
throw new Scribunto_LuaError( "Unmatched close-paren at pattern character $ii" );
}
array_pop( $opencapt );
$re .= $pat[$i];
break;
case '%':
$i++;
if ( $i >= $len ) {
throw new Scribunto_LuaError( "malformed pattern (ends with '%')" );
}
if ( isset( $charsets[$pat[$i]] ) ) {
$re .= $charsets[$pat[$i]];
$q = true;
} elseif ( $pat[$i] === 'b' ) {
if ( $i + 2 >= $len ) {
throw new Scribunto_LuaError( "malformed pattern (missing arguments to \'%b\')" );
}
$d1 = preg_quote( $pat[++$i], '/' );
$d2 = preg_quote( $pat[++$i], '/' );
if ( $d1 === $d2 ) {
$re .= "{$d1}[^$d1]*$d1";
} else {
$bct++;
$re .= "(?<b$bct>$d1(?:(?>[^$d1$d2]+)|(?P>b$bct))*$d2)";
}
} elseif ( $pat[$i] === 'f' ) {
if ( $i + 1 >= $len || $pat[++$i] !== '[' ) {
throw new Scribunto_LuaError( "missing '[' after %f in pattern at pattern character $ii" );
}
list( $i, $re2 ) = $this->bracketedCharSetToRegex( $pat, $i, $len, $brcharsets );
// Because %f considers the beginning and end of the string
// to be \0, determine if $re2 matches that and take it
// into account with "^" and "$".
if ( preg_match( "/$re2/us", "\0" ) ) {
$re .= "(?<!^)(?<!$re2)(?=$re2|$)";
} else {
$re .= "(?<!$re2)(?=$re2)";
}
} elseif ( $pat[$i] >= '0' && $pat[$i] <= '9' ) {
$n = ord( $pat[$i] ) - 0x30;
if ( $n === 0 || $n > count( $capt ) || in_array( $n, $opencapt ) ) {
throw new Scribunto_LuaError( "invalid capture index %$n at pattern character $ii" );
}
$re .= "\\g{m$n}";
} else {
$re .= preg_quote( $pat[$i], '/' );
$q = true;
}
break;
case '[':
list( $i, $re2 ) = $this->bracketedCharSetToRegex( $pat, $i, $len, $brcharsets );
$re .= $re2;
$q = true;
break;
case ']':
throw new Scribunto_LuaError( "Unmatched close-bracket at pattern character $ii" );
case '.':
$re .= $pat[$i];
$q = true;
break;
default:
$re .= preg_quote( $pat[$i], '/' );
$q = true;
break;
}
if ( $q && $i + 1 < $len ) {
switch ( $pat[$i + 1] ) {
case '*':
case '+':
case '?':
$re .= $pat[++$i];
break;
case '-':
$re .= '*?';
$i++;
break;
}
}
}
if ( count( $opencapt ) ) {
$ii = $captparen[$opencapt[0]];
throw new Scribunto_LuaError( "Unclosed capture beginning at pattern character $ii" );
}
$re .= '/us';
$this->patternRegexCache->set( $cacheKey, [ $re, $capt, $anypos ] );
}
return $this->patternRegexCache->get( $cacheKey );
}
private function bracketedCharSetToRegex( $pat, $i, $len, $brcharsets ) {
$ii = $i + 1;
$re = '[';
$i++;
if ( $i < $len && $pat[$i] === '^' ) {
$re .= '^';
$i++;
}
for ( $j = $i; $i < $len && ( $j == $i || $pat[$i] !== ']' ); $i++ ) {
if ( $pat[$i] === '%' ) {
$i++;
if ( $i >= $len ) {
break;
}
if ( isset( $brcharsets[$pat[$i]] ) ) {
$re .= $brcharsets[$pat[$i]];
} else {
$re .= preg_quote( $pat[$i], '/' );
}
} elseif ( $i + 2 < $len &&
$pat[$i + 1] === '-' && $pat[$i + 2] !== ']' && $pat[$i + 2] !== '%'
) {
if ( $pat[$i] <= $pat[$i + 2] ) {
$re .= preg_quote( $pat[$i], '/' ) . '-' . preg_quote( $pat[$i + 2], '/' );
}
$i += 2;
} else {
$re .= preg_quote( $pat[$i], '/' );
}
}
if ( $i >= $len ) {
throw new Scribunto_LuaError(
"Missing close-bracket for character set beginning at pattern character $ii"
);
}
$re .= ']';
// Lua just ignores invalid ranges, while pcre throws an error.
// We filter them out above, but then we need to special-case empty sets
if ( $re === '[]' ) {
// Can't directly quantify (*FAIL), so wrap it.
// "(?!)" would be simpler and could be quantified if not for a bug in PCRE 8.13 to 8.33
$re = '(?:(*FAIL))';
} elseif ( $re === '[^]' ) {
$re = '.'; // 's' modifier is always used, so this works
}
return [ $i, $re ];
}
private function addCapturesFromMatch( $arr, $s, $m, $capt, $m0_if_no_captures ) {
if ( count( $capt ) ) {
foreach ( $capt as $n => $pos ) {
if ( $pos ) {
$o = mb_strlen( substr( $s, 0, $m["m$n"][1] ), 'UTF-8' ) + 1;
$arr[] = $o;
} else {
$arr[] = $m["m$n"][0];
}
}
} elseif ( $m0_if_no_captures ) {
$arr[] = $m[0][0];
}
return $arr;
}
public function ustringFind( $s, $pattern, $init = 1, $plain = false ) {
$this->checkString( 'find', $s );
$this->checkTypeOptional( 'find', 3, $init, 'number', 1 );
$this->checkTypeOptional( 'find', 4, $plain, 'boolean', false );
$len = mb_strlen( $s, 'UTF-8' );
if ( $init < 0 ) {
$init = $len + $init + 1;
} elseif ( $init > $len + 1 ) {
$init = $len + 1;
}
if ( $init > 1 ) {
$offset = strlen( mb_substr( $s, 0, $init - 1, 'UTF-8' ) );
} else {
$init = 1;
$offset = 0;
}
if ( $plain ) {
$this->checkPattern( 'find', $pattern );
if ( $pattern !== '' ) {
$ret = mb_strpos( $s, $pattern, $init - 1, 'UTF-8' );
} else {
$ret = $init - 1;
}
if ( $ret === false ) {
return [ null ];
} else {
return [ $ret + 1, $ret + mb_strlen( $pattern ) ];
}
} else {
list( $re, $capt ) = $this->patternToRegex( $pattern, '\G', 'find' );
if ( !preg_match( $re, $s, $m, PREG_OFFSET_CAPTURE, $offset ) ) {
return [ null ];
}
$o = mb_strlen( substr( $s, 0, $m[0][1] ), 'UTF-8' );
$ret = [ $o + 1, $o + mb_strlen( $m[0][0], 'UTF-8' ) ];
return $this->addCapturesFromMatch( $ret, $s, $m, $capt, false );
}
}
public function ustringMatch( $s, $pattern, $init = 1 ) {
$this->checkString( 'match', $s );
$this->checkTypeOptional( 'match', 3, $init, 'number', 1 );
$len = mb_strlen( $s, 'UTF-8' );
if ( $init < 0 ) {
$init = $len + $init + 1;
} elseif ( $init > $len + 1 ) {
$init = $len + 1;
}
if ( $init > 1 ) {
$offset = strlen( mb_substr( $s, 0, $init - 1, 'UTF-8' ) );
} else {
$offset = 0;
}
list( $re, $capt ) = $this->patternToRegex( $pattern, '\G', 'match' );
if ( !preg_match( $re, $s, $m, PREG_OFFSET_CAPTURE, $offset ) ) {
return [ null ];
}
return $this->addCapturesFromMatch( [], $s, $m, $capt, true );
}
public function ustringGmatchInit( $s, $pattern ) {
$this->checkString( 'gmatch', $s );
list( $re, $capt ) = $this->patternToRegex( $pattern, false, 'gmatch' );
return [ $re, $capt ];
}
public function ustringGmatchCallback( $s, $re, $capt, $pos ) {
if ( !preg_match( $re, $s, $m, PREG_OFFSET_CAPTURE, $pos ) ) {
return [ $pos, [] ];
}
$pos = $m[0][1] + strlen( $m[0][0] );
return [ $pos, $this->addCapturesFromMatch( [ null ], $s, $m, $capt, true ) ];
}
public function ustringGsub( $s, $pattern, $repl, $n = null ) {
$this->checkString( 'gsub', $s );
$this->checkTypeOptional( 'gsub', 4, $n, 'number', null );
if ( $n === null ) {
$n = -1;
} elseif ( $n < 1 ) {
return [ $s, 0 ];
}
list( $re, $capt, $anypos ) = $this->patternToRegex( $pattern, '^', 'gsub' );
$captures = [];
if ( $this->phpBug53823 ) {
// PHP bug 53823 means that a zero-length match before a UTF-8
// character will match again before every byte of that character.
// The workaround is to capture the first "character" of/after the
// match and verify that its first byte is legal to start a UTF-8
// character.
$re = '/(?=(?<phpBug53823>.|$))' . substr( $re, 1 );
}
if ( $anypos ) {
// preg_replace_callback doesn't take a "flags" argument, so we
// can't pass PREG_OFFSET_CAPTURE to it, which is needed to handle
// position captures. So instead we have to do a preg_match_all and
// handle the captures ourself.
$ct = preg_match_all( $re, $s, $mm, PREG_OFFSET_CAPTURE | PREG_SET_ORDER );
for ( $i = 0; $i < $ct; $i++ ) {
$m = $mm[$i];
if ( $this->phpBug53823 ) {
$c = ord( $m['phpBug53823'][0] );
if ( $c >= 0x80 && $c <= 0xbf ) {
continue;
}
}
$c = [ $m[0][0] ];
foreach ( $this->addCapturesFromMatch( [], $s, $m, $capt, false ) as $k => $v ) {
$k++;
$c["m$k"] = $v;
}
$captures[] = $c;
if ( $n >= 0 && count( $captures ) >= $n ) {
break;
}
}
}
switch ( $this->getLuaType( $repl ) ) {
case 'string':
case 'number':
$cb = function ( $m ) use ( $repl, $anypos, &$captures ) {
if ( $anypos ) {
$m = array_shift( $captures );
}
return preg_replace_callback( '/%([%0-9])/', function ( $m2 ) use ( $m ) {
$x = $m2[1];
if ( $x === '%' ) {
return '%';
} elseif ( $x === '0' ) {
return $m[0];
} elseif ( isset( $m["m$x"] ) ) {
return $m["m$x"];
} else {
throw new Scribunto_LuaError( "invalid capture index %$x in replacement string" );
}
}, $repl );
};
break;
case 'table':
$cb = function ( $m ) use ( $repl, $anypos, &$captures ) {
if ( $anypos ) {
$m = array_shift( $captures );
}
$x = isset( $m['m1'] ) ? $m['m1'] : $m[0];
return isset( $repl[$x] ) ? $repl[$x] : $m[0];
};
break;
case 'function':
$interpreter = $this->getInterpreter();
$cb = function ( $m ) use ( $interpreter, $capt, $repl, $anypos, &$captures ) {
if ( $anypos ) {
$m = array_shift( $captures );
}
$args = [ $repl ];
if ( count( $capt ) ) {
foreach ( $capt as $i => $pos ) {
$args[] = $m["m$i"];
}
} else {
$args[] = $m[0];
}
$ret = call_user_func_array( [ $interpreter, 'callFunction' ], $args );
if ( count( $ret ) === 0 || $ret[0] === null ) {
return $m[0];
}
return $ret[0];
};
break;
default:
$this->checkType( 'gsub', 3, $repl, 'function or table or string' );
}
$skippedMatches = 0;
if ( $this->phpBug53823 ) {
// Since we're having bogus matches, we need to keep track of the
// necessary adjustment and stop manually once we hit the limit.
$maxMatches = $n < 0 ? INF : $n;
$n = -1;
$realCallback = $cb;
$cb = function ( $m ) use ( $realCallback, &$skippedMatches, &$maxMatches ) {
$c = ord( $m['phpBug53823'] );
if ( $c >= 0x80 && $c <= 0xbf || $maxMatches <= 0 ) {
$skippedMatches++;
return $m[0];
} else {
$maxMatches--;
return $realCallback( $m );
}
};
}
$count = 0;
$s2 = preg_replace_callback( $re, $cb, $s, $n, $count );
if ( $s2 === null ) {
self::handlePCREError( preg_last_error(), $pattern );
}
return [ $s2, $count - $skippedMatches ];
}
/**
* Handle a PCRE error
* @param int $error From preg_last_error()
* @param string $pattern Pattern being matched
* @throws Scribunto_LuaError
*/
private function handlePCREError( $error, $pattern ) {
$PREG_JIT_STACKLIMIT_ERROR = defined( 'PREG_JIT_STACKLIMIT_ERROR' )
? PREG_JIT_STACKLIMIT_ERROR
: 'PREG_JIT_STACKLIMIT_ERROR';
$error = preg_last_error();
switch ( $error ) {
case PREG_NO_ERROR:
// Huh?
break;
case PREG_INTERNAL_ERROR:
throw new Scribunto_LuaError( "PCRE internal error" );
case PREG_BACKTRACK_LIMIT_ERROR:
throw new Scribunto_LuaError(
"PCRE backtrack limit reached while matching pattern '$pattern'"
);
case PREG_RECURSION_LIMIT_ERROR:
throw new Scribunto_LuaError(
"PCRE recursion limit reached while matching pattern '$pattern'"
);
case PREG_BAD_UTF8_ERROR:
// Should have alreay been caught, but just in case
throw new Scribunto_LuaError( "PCRE bad UTF-8 error" );
case PREG_BAD_UTF8_OFFSET_ERROR:
// Shouldn't happen, but just in case
throw new Scribunto_LuaError( "PCRE bad UTF-8 offset error" );
case $PREG_JIT_STACKLIMIT_ERROR:
throw new Scribunto_LuaError(
"PCRE JIT stack limit reached while matching pattern '$pattern'"
);
default:
throw new Scribunto_LuaError(
"PCRE error code $error while matching pattern '$pattern'"
);
}
}
}