Annotation of src/lib/libc/regex/regex2.h, Revision 1.1
1.1 ! jtc 1: /*
! 2: * First, the stuff that ends up in the outside-world include file
! 3: = typedef off_t regoff_t;
! 4: = typedef struct {
! 5: = int re_magic;
! 6: = size_t re_nsub; // number of parenthesized subexpressions
! 7: = const char *re_endp; // end pointer for REG_PEND
! 8: = struct re_guts *re_g; // none of your business :-)
! 9: = } regex_t;
! 10: = typedef struct {
! 11: = regoff_t rm_so; // start of match
! 12: = regoff_t rm_eo; // end of match
! 13: = } regmatch_t;
! 14: */
! 15: /*
! 16: * internals of regex_t
! 17: */
! 18: #define MAGIC1 ((('r'^0200)<<8) | 'e')
! 19:
! 20: /*
! 21: * The internal representation is a *strip*, a sequence of
! 22: * operators ending with an endmarker. (Some terminology etc. is a
! 23: * historical relic of earlier versions which used multiple strips.)
! 24: * Certain oddities in the representation are there to permit running
! 25: * the machinery backwards; in particular, any deviation from sequential
! 26: * flow must be marked at both its source and its destination. Some
! 27: * fine points:
! 28: *
! 29: * - OPLUS_ and O_PLUS are *inside* the loop they create.
! 30: * - OQUEST_ and O_QUEST are *outside* the bypass they create.
! 31: * - OCH_ and O_CH are *outside* the multi-way branch they create, while
! 32: * OOR1 and OOR2 are respectively the end and the beginning of one of
! 33: * the branches. Note that there is an implicit OOR2 following OCH_
! 34: * and an implicit OOR1 preceding O_CH.
! 35: *
! 36: * In state representations, an operator's bit is on to signify a state
! 37: * immediately *preceding* "execution" of that operator.
! 38: */
! 39: typedef unsigned long sop; /* strip operator */
! 40: typedef long sopno;
! 41: #define OPRMASK 0xf8000000
! 42: #define OPDMASK 0x07ffffff
! 43: #define OPSHIFT ((unsigned)27)
! 44: #define OP(n) ((n)&OPRMASK)
! 45: #define OPND(n) ((n)&OPDMASK)
! 46: #define SOP(op, opnd) ((op)|(opnd))
! 47: /* operators meaning operand */
! 48: /* (back, fwd are offsets) */
! 49: #define OEND (1<<OPSHIFT) /* endmarker - */
! 50: #define OCHAR (2<<OPSHIFT) /* character unsigned char */
! 51: #define OBOL (3<<OPSHIFT) /* left anchor - */
! 52: #define OEOL (4<<OPSHIFT) /* right anchor - */
! 53: #define OANY (5<<OPSHIFT) /* . - */
! 54: #define OANYOF (6<<OPSHIFT) /* [...] set number */
! 55: #define OBACK_ (7<<OPSHIFT) /* begin \d paren number */
! 56: #define O_BACK (8<<OPSHIFT) /* end \d paren number */
! 57: #define OPLUS_ (9<<OPSHIFT) /* + prefix fwd to suffix */
! 58: #define O_PLUS (10<<OPSHIFT) /* + suffix back to prefix */
! 59: #define OQUEST_ (11<<OPSHIFT) /* ? prefix fwd to suffix */
! 60: #define O_QUEST (12<<OPSHIFT) /* ? suffix back to prefix */
! 61: #define OLPAREN (13<<OPSHIFT) /* ( fwd to ) */
! 62: #define ORPAREN (14<<OPSHIFT) /* ) back to ( */
! 63: #define OCH_ (15<<OPSHIFT) /* begin choice fwd to OOR2 */
! 64: #define OOR1 (16<<OPSHIFT) /* | pt. 1 back to OOR1 or OCH_ */
! 65: #define OOR2 (17<<OPSHIFT) /* | pt. 2 fwd to OOR2 or O_CH */
! 66: #define O_CH (18<<OPSHIFT) /* end choice back to OOR1 */
! 67: #define OBOW (19<<OPSHIFT) /* begin word - */
! 68: #define OEOW (20<<OPSHIFT) /* end word - */
! 69:
! 70: /*
! 71: * Structure for [] character-set representation. Character sets are
! 72: * done as bit vectors, grouped 8 to a byte vector for compactness.
! 73: * The individual set therefore has both a pointer to the byte vector
! 74: * and a mask to pick out the relevant bit of each byte. A hash code
! 75: * simplifies testing whether two sets could be identical.
! 76: *
! 77: * This will get trickier for multicharacter collating elements. As
! 78: * preliminary hooks for dealing with such things, we also carry along
! 79: * a string of multi-character elements, and decide the size of the
! 80: * vectors at run time.
! 81: */
! 82: typedef struct {
! 83: uchar *ptr; /* -> uchar [csetsize] */
! 84: uchar mask; /* bit within array */
! 85: uchar hash; /* hash code */
! 86: size_t smultis;
! 87: char *multis; /* -> char[smulti] ab\0cd\0ef\0\0 */
! 88: } cset;
! 89: /* note that CHadd and CHsub are unsafe, and CHIN doesn't yield 0/1 */
! 90: #define CHadd(cs, c) ((cs)->ptr[(uchar)(c)] |= (cs)->mask, (cs)->hash += (c))
! 91: #define CHsub(cs, c) ((cs)->ptr[(uchar)(c)] &= ~(cs)->mask, (cs)->hash -= (c))
! 92: #define CHIN(cs, c) ((cs)->ptr[(uchar)(c)] & (cs)->mask)
! 93: #define MCadd(cs, cp) mcadd(p, cs, cp) /* regcomp() internal fns */
! 94: #define MCsub(cs, cp) mcsub(cs, cp)
! 95: #define MCin(cs, cp) mcin(cs, cp)
! 96:
! 97: /* stuff for character categories */
! 98: typedef unsigned char cat_t;
! 99:
! 100: /*
! 101: * main compiled-expression structure
! 102: */
! 103: struct re_guts {
! 104: int magic;
! 105: # define MAGIC2 ((('R'^0200)<<8)|'E')
! 106: sop *strip; /* malloced area for strip */
! 107: int csetsize; /* number of bits in a cset vector */
! 108: int ncsets; /* number of csets in use */
! 109: cset *sets; /* -> cset [ncsets] */
! 110: uchar *setbits; /* -> uchar[csetsize][ncsets/CHAR_BIT] */
! 111: int cflags; /* copy of regcomp() cflags argument */
! 112: sopno nstates; /* = number of sops */
! 113: sopno firststate; /* the initial OEND (normally 0) */
! 114: sopno laststate; /* the final OEND */
! 115: int iflags; /* internal flags */
! 116: # define USEBOL 01 /* used ^ */
! 117: # define USEEOL 02 /* used $ */
! 118: # define BAD 04 /* something wrong */
! 119: int nbol; /* number of ^ used */
! 120: int neol; /* number of $ used */
! 121: int ncategories; /* how many character categories */
! 122: cat_t *categories; /* ->catspace[-CHAR_MIN] */
! 123: char *must; /* match must contain this string */
! 124: int mlen; /* length of must */
! 125: size_t nsub; /* copy of re_nsub */
! 126: int backrefs; /* does it use back references? */
! 127: sopno nplus; /* how deep does it nest +s? */
! 128: /* catspace must be last */
! 129: cat_t catspace[1]; /* actually [NC] */
! 130: };
! 131:
! 132: /* misc utilities */
! 133: #define OUT (CHAR_MAX+1) /* a non-character value */
CVSweb <webmaster@jp.NetBSD.org>