/* * First, the stuff that ends up in the outside-world include file = typedef off_t regoff_t; = typedef struct { = int re_magic; = size_t re_nsub; // number of parenthesized subexpressions = const char *re_endp; // end pointer for REG_PEND = struct re_guts *re_g; // none of your business :-) = } regex_t; = typedef struct { = regoff_t rm_so; // start of match = regoff_t rm_eo; // end of match = } regmatch_t; */ /* * internals of regex_t */ #define MAGIC1 ((('r'^0200)<<8) | 'e') /* * The internal representation is a *strip*, a sequence of * operators ending with an endmarker. (Some terminology etc. is a * historical relic of earlier versions which used multiple strips.) * Certain oddities in the representation are there to permit running * the machinery backwards; in particular, any deviation from sequential * flow must be marked at both its source and its destination. Some * fine points: * * - OPLUS_ and O_PLUS are *inside* the loop they create. * - OQUEST_ and O_QUEST are *outside* the bypass they create. * - OCH_ and O_CH are *outside* the multi-way branch they create, while * OOR1 and OOR2 are respectively the end and the beginning of one of * the branches. Note that there is an implicit OOR2 following OCH_ * and an implicit OOR1 preceding O_CH. * * In state representations, an operator's bit is on to signify a state * immediately *preceding* "execution" of that operator. */ typedef long sop; /* strip operator */ typedef long sopno; #define OPRMASK 0x7c000000 #define OPDMASK 0x03ffffff #define OPSHIFT (26) #define OP(n) ((n)&OPRMASK) #define OPND(n) ((n)&OPDMASK) #define SOP(op, opnd) ((op)|(opnd)) /* operators meaning operand */ /* (back, fwd are offsets) */ #define OEND (1<<OPSHIFT) /* endmarker - */ #define OCHAR (2<<OPSHIFT) /* character unsigned char */ #define OBOL (3<<OPSHIFT) /* left anchor - */ #define OEOL (4<<OPSHIFT) /* right anchor - */ #define OANY (5<<OPSHIFT) /* . - */ #define OANYOF (6<<OPSHIFT) /* [...] set number */ #define OBACK_ (7<<OPSHIFT) /* begin \d paren number */ #define O_BACK (8<<OPSHIFT) /* end \d paren number */ #define OPLUS_ (9<<OPSHIFT) /* + prefix fwd to suffix */ #define O_PLUS (10<<OPSHIFT) /* + suffix back to prefix */ #define OQUEST_ (11<<OPSHIFT) /* ? prefix fwd to suffix */ #define O_QUEST (12<<OPSHIFT) /* ? suffix back to prefix */ #define OLPAREN (13<<OPSHIFT) /* ( fwd to ) */ #define ORPAREN (14<<OPSHIFT) /* ) back to ( */ #define OCH_ (15<<OPSHIFT) /* begin choice fwd to OOR2 */ #define OOR1 (16<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */ #define OOR2 (17<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */ #define O_CH (18<<OPSHIFT) /* end choice back to OOR1 */ #define OBOW (19<<OPSHIFT) /* begin word - */ #define OEOW (20<<OPSHIFT) /* end word - */ /* * Structure for [] character-set representation. Character sets are * done as bit vectors, grouped 8 to a byte vector for compactness. * The individual set therefore has both a pointer to the byte vector * and a mask to pick out the relevant bit of each byte. A hash code * simplifies testing whether two sets could be identical. * * This will get trickier for multicharacter collating elements. As * preliminary hooks for dealing with such things, we also carry along * a string of multi-character elements, and decide the size of the * vectors at run time. */ typedef struct { uch *ptr; /* -> uch [csetsize] */ uch mask; /* bit within array */ uch hash; /* hash code */ size_t smultis; char *multis; /* -> char[smulti] ab\0cd\0ef\0\0 */ } cset; /* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */ #define CHadd(cs, c) ((cs)->ptr[(uch)(c)] |= (cs)->mask, (cs)->hash += (c)) #define CHsub(cs, c) ((cs)->ptr[(uch)(c)] &= ~(cs)->mask, (cs)->hash -= (c)) #define CHIN(cs, c) ((cs)->ptr[(uch)(c)] & (cs)->mask) #define MCadd(p, cs, cp) mcadd(p, cs, cp) /* regcomp() internal fns */ #define MCsub(p, cs, cp) mcsub(p, cs, cp) #define MCin(p, cs, cp) mcin(p, cs, cp) /* stuff for character categories */ typedef unsigned char cat_t; /* * main compiled-expression structure */ struct re_guts { int magic; # define MAGIC2 ((('R'^0200)<<8)|'E') sop *strip; /* malloced area for strip */ int csetsize; /* number of bits in a cset vector */ int ncsets; /* number of csets in use */ cset *sets; /* -> cset [ncsets] */ uch *setbits; /* -> uch[csetsize][ncsets/CHAR_BIT] */ int cflags; /* copy of regcomp() cflags argument */ sopno nstates; /* = number of sops */ sopno firststate; /* the initial OEND (normally 0) */ sopno laststate; /* the final OEND */ int iflags; /* internal flags */ # define USEBOL 01 /* used ^ */ # define USEEOL 02 /* used $ */ # define BAD 04 /* something wrong */ int nbol; /* number of ^ used */ int neol; /* number of $ used */ int ncategories; /* how many character categories */ cat_t *categories; /* ->catspace[-CHAR_MIN] */ char *must; /* match must contain this string */ int mlen; /* length of must */ size_t nsub; /* copy of re_nsub */ int backrefs; /* does it use back references? */ sopno nplus; /* how deep does it nest +s? */ /* catspace must be last */ cat_t catspace[1]; /* actually [NC] */ }; /* misc utilities */ #define OUT (CHAR_MAX+1) /* a non-character value */ #define ISWORD(c) (isalnum(c) || (c) == '_')