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-rw-r--r--xc/extras/regex/regex2.h134
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+/*
+ * 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) == '_')