// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html // // regexcmp.h // // Copyright (C) 2002-2016, International Business Machines Corporation and others. // All Rights Reserved. // // This file contains declarations for the class RegexCompile // // This class is internal to the regular expression implementation. // For the public Regular Expression API, see the file "unicode/regex.h" // #ifndef RBBISCAN_H #define RBBISCAN_H #include "unicode/utypes.h" #if !UCONFIG_NO_REGULAR_EXPRESSIONS #include "unicode/parseerr.h" #include "unicode/uniset.h" #include "unicode/uobject.h" #include "unicode/utext.h" #include "uhash.h" #include "uvector.h" #include "uvectr32.h" U_NAMESPACE_BEGIN //-------------------------------------------------------------------------------- // // class RegexCompile Contains the regular expression compiler. // //-------------------------------------------------------------------------------- struct RegexTableEl; class RegexPattern; class U_I18N_API RegexCompile : public UMemory { public: enum { kStackSize = 100 // The size of the state stack for }; // pattern parsing. Corresponds roughly // to the depth of parentheses nesting // that is allowed in the rules. struct RegexPatternChar { UChar32 fChar; UBool fQuoted; }; RegexCompile(RegexPattern *rp, UErrorCode &e); void compile(const UnicodeString &pat, UParseError &pp, UErrorCode &e); void compile(UText *pat, UParseError &pp, UErrorCode &e); virtual ~RegexCompile(); void nextChar(RegexPatternChar &c); // Get the next char from the input stream. static void cleanup(); // Memory cleanup // Categories of parentheses in pattern. // The category is saved in the compile-time parentheses stack frame, and // determines the code to be generated when the matching close ) is encountered. enum EParenClass { plain = -1, // No special handling capturing = -2, atomic = -3, lookAhead = -4, negLookAhead = -5, flags = -6, lookBehind = -7, lookBehindN = -8 }; private: UBool doParseActions(int32_t a); void error(UErrorCode e); // error reporting convenience function. UChar32 nextCharLL(); UChar32 peekCharLL(); UnicodeSet *scanProp(); UnicodeSet *scanPosixProp(); void handleCloseParen(); int32_t blockTopLoc(UBool reserve); // Locate a position in the compiled pattern // at the top of the just completed block // or operation, and optionally ensure that // there is space to add an opcode there. void compileSet(UnicodeSet *theSet); // Generate the compiled pattern for // a reference to a UnicodeSet. void compileInterval(int32_t InitOp, // Generate the code for a {min,max} quantifier. int32_t LoopOp); UBool compileInlineInterval(); // Generate inline code for a {min,max} quantifier void literalChar(UChar32 c); // Compile a literal char void fixLiterals(UBool split=FALSE); // Generate code for pending literal characters. void insertOp(int32_t where); // Open up a slot for a new op in the // generated code at the specified location. void appendOp(int32_t op); // Append a new op to the compiled pattern. void appendOp(int32_t type, int32_t val); // Build & append a new op to the compiled pattern. int32_t buildOp(int32_t type, int32_t val); // Construct a new pcode instruction. int32_t allocateData(int32_t size); // Allocate space in the matcher data area. // Return index of the newly allocated data. int32_t allocateStackData(int32_t size); // Allocate space in the match back-track stack frame. // Return offset index in the frame. int32_t minMatchLength(int32_t start, int32_t end); int32_t maxMatchLength(int32_t start, int32_t end); void matchStartType(); void stripNOPs(); void setEval(int32_t op); void setPushOp(int32_t op); UChar32 scanNamedChar(); UnicodeSet *createSetForProperty(const UnicodeString &propName, UBool negated); public: // Public for testing only. static void U_EXPORT2 findCaseInsensitiveStarters(UChar32 c, UnicodeSet *starterChars); private: UErrorCode *fStatus; RegexPattern *fRXPat; UParseError *fParseErr; // // Data associated with low level character scanning // int64_t fScanIndex; // Index of current character being processed // in the rule input string. UBool fQuoteMode; // Scan is in a \Q...\E quoted region UBool fInBackslashQuote; // Scan is between a '\' and the following char. UBool fEOLComments; // When scan is just after '(?', inhibit #... to // end of line comments, in favor of (?#...) comments. int64_t fLineNum; // Line number in input file. int64_t fCharNum; // Char position within the line. UChar32 fLastChar; // Previous char, needed to count CR-LF // as a single line, not two. UChar32 fPeekChar; // Saved char, if we've scanned ahead. RegexPatternChar fC; // Current char for parse state machine // processing. // // Data for the state machine that parses the regular expression. // RegexTableEl **fStateTable; // State Transition Table for regex Rule // parsing. index by p[state][char-class] uint16_t fStack[kStackSize]; // State stack, holds state pushes int32_t fStackPtr; // and pops as specified in the state // transition rules. // // Data associated with the generation of the pcode for the match engine // int32_t fModeFlags; // Match Flags. (Case Insensitive, etc.) // Always has high bit (31) set so that flag values // on the paren stack are distinguished from relocatable // pcode addresses. int32_t fNewModeFlags; // New flags, while compiling (?i, holds state // until last flag is scanned. UBool fSetModeFlag; // true for (?ismx, false for (?-ismx UnicodeString fLiteralChars; // Literal chars or strings from the pattern are accumulated here. // Once completed, meaning that some non-literal pattern // construct is encountered, the appropriate opcodes // to match the literal will be generated, and this // string will be cleared. int64_t fPatternLength; // Length of the input pattern string. UVector32 fParenStack; // parentheses stack. Each frame consists of // the positions of compiled pattern operations // needing fixup, followed by negative value. The // first entry in each frame is the position of the // spot reserved for use when a quantifier // needs to add a SAVE at the start of a (block) // The negative value (-1, -2,...) indicates // the kind of paren that opened the frame. Some // need special handling on close. int32_t fMatchOpenParen; // The position in the compiled pattern // of the slot reserved for a state save // at the start of the most recently processed // parenthesized block. Updated when processing // a close to the location for the corresponding open. int32_t fMatchCloseParen; // The position in the pattern of the first // location after the most recently processed // parenthesized block. int32_t fIntervalLow; // {lower, upper} interval quantifier values. int32_t fIntervalUpper; // Placed here temporarily, when pattern is // initially scanned. Each new interval // encountered overwrites these values. // -1 for the upper interval value means none // was specified (unlimited occurences.) int64_t fNameStartPos; // Starting position of a \N{NAME} name in a // pattern, valid while remainder of name is // scanned. UStack fSetStack; // Stack of UnicodeSets, used while evaluating // (at compile time) set expressions within // the pattern. UStack fSetOpStack; // Stack of pending set operators (&&, --, union) UChar32 fLastSetLiteral; // The last single code point added to a set. // needed when "-y" is scanned, and we need // to turn "x-y" into a range. UnicodeString *fCaptureName; // Named Capture, the group name is built up // in this string while being scanned. }; // Constant values to be pushed onto fSetOpStack while scanning & evalueating [set expressions] // The high 16 bits are the operator precedence, and the low 16 are a code for the operation itself. enum SetOperations { setStart = 0 << 16 | 1, setEnd = 1 << 16 | 2, setNegation = 2 << 16 | 3, setCaseClose = 2 << 16 | 9, setDifference2 = 3 << 16 | 4, // '--' set difference operator setIntersection2 = 3 << 16 | 5, // '&&' set intersection operator setUnion = 4 << 16 | 6, // implicit union of adjacent items setDifference1 = 4 << 16 | 7, // '-', single dash difference op, for compatibility with old UnicodeSet. setIntersection1 = 4 << 16 | 8 // '&', single amp intersection op, for compatibility with old UnicodeSet. }; U_NAMESPACE_END #endif // !UCONFIG_NO_REGULAR_EXPRESSIONS #endif // RBBISCAN_H