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Diffstat (limited to 'regex/regex2.h')
| -rw-r--r-- | regex/regex2.h | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/regex/regex2.h b/regex/regex2.h new file mode 100644 index 0000000..58fd8d8 --- /dev/null +++ b/regex/regex2.h @@ -0,0 +1,134 @@ +/* + * 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) == '_') |