mediawiki-extensions-Scribunto/includes/engines/LuaCommon/UstringLibrary.php
libraryupgrader 7b2cda5591 build: Updating composer dependencies
* mediawiki/minus-x: 0.3.2 → 1.0.0
* jakub-onderka/php-console-highlighter: 0.3.2 → 0.4.0
* mediawiki/mediawiki-phan-config: 0.9.0 → 0.9.1

Change-Id: Ibdedddbf19eb4712c31c1b95024391ff013f73e8
2020-02-07 06:37:29 +00:00

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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;
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;
/** @inheritDoc */
public 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 );
}
public 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,
] );
}
/**
* Check a string first parameter
* @param string $name Function name, for errors
* @param mixed $s Value to check
* @param bool $checkEncoding Whether to validate UTF-8 encoding.
*/
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)"
);
}
}
}
/**
* Handler for isUtf8
* @internal
* @param string $s
* @return bool[]
*/
public function ustringIsUtf8( $s ) {
$this->checkString( 'isutf8', $s, false );
return [ mb_check_encoding( $s, 'UTF-8' ) ];
}
/**
* Handler for byteoffset
* @internal
* @param string $s
* @param int $l
* @param int $i
* @return int[]|null[]
*/
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 ];
}
}
/**
* Handler for codepoint
* @internal
* @param string $s
* @param int $i
* @param int|null $j
* @return int[]
*/
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' ) );
}
/**
* Handler for gcodepointInit
* @internal
* @param string $s
* @param int $i
* @param int|null $j
* @return int[][]
*/
public function ustringGcodepointInit( $s, $i = 1, $j = null ) {
return [ $this->ustringCodepoint( $s, $i, $j ) ];
}
/**
* Handler for toNFC
* @internal
* @param string $s
* @return string[]|null[]
*/
public function ustringToNFC( $s ) {
$this->checkString( 'toNFC', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFC( $s ) ];
}
/**
* Handler for toNFD
* @internal
* @param string $s
* @return string[]|null[]
*/
public function ustringToNFD( $s ) {
$this->checkString( 'toNFD', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFD( $s ) ];
}
/**
* Handler for toNFKC
* @internal
* @param string $s
* @return string[]|null[]
*/
public function ustringToNFKC( $s ) {
$this->checkString( 'toNFKC', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFKC( $s ) ];
}
/**
* Handler for toNFKD
* @internal
* @param string $s
* @return string[]|null[]
*/
public function ustringToNFKD( $s ) {
$this->checkString( 'toNFKD', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ Validator::toNFKD( $s ) ];
}
/**
* Handler for char
* @internal
* @return string[]
*/
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)" );
}
}
$s = pack( 'N*', ...$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 ];
}
/**
* Handler for len
* @internal
* @param string $s
* @return int[]|null[]
*/
public function ustringLen( $s ) {
$this->checkString( 'len', $s, false );
if ( !mb_check_encoding( $s, 'UTF-8' ) ) {
return [ null ];
}
return [ mb_strlen( $s, 'UTF-8' ) ];
}
/**
* Handler for sub
* @internal
* @param string $s
* @param int $i
* @param int $j
* @return string[]
*/
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 ];
}
/**
* Handler for upper
* @internal
* @param string $s
* @return string[]
*/
public function ustringUpper( $s ) {
$this->checkString( 'upper', $s );
return [ mb_strtoupper( $s, 'UTF-8' ) ];
}
/**
* Handler for lower
* @internal
* @param string $s
* @return string[]
*/
public function ustringLower( $s ) {
$this->checkString( 'lower', $s );
return [ mb_strtolower( $s, 'UTF-8' ) ];
}
/**
* Check a pattern as the second argument
* @param string $name Lua function name, for errors
* @param mixed $pattern Lua pattern
*/
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
* @param string $pattern Lua pattern to convert
* @param string|false $anchor Regex fragment (`^` or `\G`) to use
* when anchoring the start of the regex, or false to disable start-anchoring.
* @param string $name Lua function name, for errors
* @return array [ string $re, array $capt, bool $anypos ]
* - $re: The regular expression
* - $capt: Definition of capturing groups, see addCapturesFromMatch()
* - $anypos: Whether any positional captures were encountered in the pattern.
*/
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 $re2 matches that and take it
// into account with "^" and "$".
// @phan-suppress-next-line PhanParamSuspiciousOrder
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 );
}
/**
* Convert a Lua pattern bracketed character set to a PCRE regex fragment
* @param string[] $pat Pattern being processed, split into individual characters.
* @param int $i Offset of the start of the bracketed character set in $pat.
* @param int $len Length of $pat.
* @param array $brcharsets Mapping from Lua pattern percent escapes to
* regex-style character ranges.
* @return array [ int $new_i, string $re_fragment ]
*/
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 ];
}
/**
* Append captured groups to a result array
* @param array $arr Result array to append to.
* @param string $s String matched against.
* @param array $m Matches, from preg_match with PREG_OFFSET_CAPTURE.
* @param array $capt Capture groups (in $m) to process, see patternToRegex()
* @param bool $m0_if_no_captures Whether to append "$0" if $capt is empty.
* @return array
*/
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;
}
/**
* Handler for find
* @internal
* @param string $s
* @param string $pattern
* @param int $init
* @param bool $plain
* @return array Format is [ null ], or [ int, int ], or [ int, int, (string|int)... ]
*/
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 );
}
}
/**
* Handler for match
* @internal
* @param string $s
* @param string $pattern
* @param int $init
* @return array Format is [ null ] or [ (string|int)... ]
*/
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 );
}
/**
* Handler for gmatchInit
* @internal
* @param string $s
* @param string $pattern
* @return array Format is [ string, bool[] ]
*/
public function ustringGmatchInit( $s, $pattern ) {
$this->checkString( 'gmatch', $s );
list( $re, $capt ) = $this->patternToRegex( $pattern, false, 'gmatch' );
return [ $re, $capt ];
}
/**
* Handler for gmatchCallback
* @internal
* @param string $s
* @param string $re
* @param bool[] $capt
* @param int $pos
* @return array Format is [ int, [ null, (string|int)... ] ]
*/
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 ) ];
}
/**
* Handler for gsub
* @internal
* @param string $s
* @param string $pattern
* @param mixed $repl
* @param string|int|null $n
* @return array Format is [ string, int ]
*/
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"];
} elseif ( $x === '1' ) {
// Match undocumented Lua string.gsub behavior
return $m[0];
} else {
throw new Scribunto_LuaError( "invalid capture index %$x in replacement string" );
}
}, $repl );
};
break;
case 'table':
$cb = function ( $m ) use ( $repl, $anypos, &$captures ) {
if ( $anypos ) {
$m = array_shift( $captures );
}
$x = $m['m1'] ?? $m[0];
if ( !isset( $repl[$x] ) || $repl[$x] === null ) {
return $m[0];
}
$type = $this->getLuaType( $repl[$x] );
if ( $type !== 'string' && $type !== 'number' ) {
throw new Scribunto_LuaError( "invalid replacement value (a $type)" );
}
return $repl[$x];
};
break;
case 'function':
$interpreter = $this->getInterpreter();
$cb = function ( $m ) use ( $interpreter, $capt, $repl, $anypos, &$captures ) {
if ( $anypos ) {
$m = array_shift( $captures );
}
$args = [];
if ( count( $capt ) ) {
foreach ( $capt as $i => $pos ) {
$args[] = $m["m$i"];
}
} else {
$args[] = $m[0];
}
$ret = $interpreter->callFunction( $repl, ...$args );
if ( count( $ret ) === 0 || $ret[0] === null ) {
return $m[0];
}
$type = $this->getLuaType( $ret[0] );
if ( $type !== 'string' && $type !== 'number' ) {
throw new Scribunto_LuaError( "invalid replacement value (a $type)" );
}
return $ret[0];
};
break;
default:
$this->checkType( 'gsub', 3, $repl, 'function or table or string' );
throw new LogicException( 'checkType above should have failed' );
}
$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'"
);
}
}
}