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Diffstat (limited to 'contrib/perl5/regcomp.h')
-rw-r--r-- | contrib/perl5/regcomp.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/contrib/perl5/regcomp.h b/contrib/perl5/regcomp.h new file mode 100644 index 0000000..526b885 --- /dev/null +++ b/contrib/perl5/regcomp.h @@ -0,0 +1,222 @@ +/* regcomp.h + */ + +typedef OP OP_4tree; /* Will be redefined later. */ + +/* + * The "internal use only" fields in regexp.h are present to pass info from + * compile to execute that permits the execute phase to run lots faster on + * simple cases. They are: + * + * regstart sv that must begin a match; Nullch if none obvious + * reganch is the match anchored (at beginning-of-line only)? + * regmust string (pointer into program) that match must include, or NULL + * [regmust changed to SV* for bminstr()--law] + * regmlen length of regmust string + * [regmlen not used currently] + * + * Regstart and reganch permit very fast decisions on suitable starting points + * for a match, cutting down the work a lot. Regmust permits fast rejection + * of lines that cannot possibly match. The regmust tests are costly enough + * that pregcomp() supplies a regmust only if the r.e. contains something + * potentially expensive (at present, the only such thing detected is * or + + * at the start of the r.e., which can involve a lot of backup). Regmlen is + * supplied because the test in pregexec() needs it and pregcomp() is computing + * it anyway. + * [regmust is now supplied always. The tests that use regmust have a + * heuristic that disables the test if it usually matches.] + * + * [In fact, we now use regmust in many cases to locate where the search + * starts in the string, so if regback is >= 0, the regmust search is never + * wasted effort. The regback variable says how many characters back from + * where regmust matched is the earliest possible start of the match. + * For instance, /[a-z].foo/ has a regmust of 'foo' and a regback of 2.] + */ + +/* + * Structure for regexp "program". This is essentially a linear encoding + * of a nondeterministic finite-state machine (aka syntax charts or + * "railroad normal form" in parsing technology). Each node is an opcode + * plus a "next" pointer, possibly plus an operand. "Next" pointers of + * all nodes except BRANCH implement concatenation; a "next" pointer with + * a BRANCH on both ends of it is connecting two alternatives. (Here we + * have one of the subtle syntax dependencies: an individual BRANCH (as + * opposed to a collection of them) is never concatenated with anything + * because of operator precedence.) The operand of some types of node is + * a literal string; for others, it is a node leading into a sub-FSM. In + * particular, the operand of a BRANCH node is the first node of the branch. + * (NB this is *not* a tree structure: the tail of the branch connects + * to the thing following the set of BRANCHes.) The opcodes are: + */ + +/* + * A node is one char of opcode followed by two chars of "next" pointer. + * "Next" pointers are stored as two 8-bit pieces, high order first. The + * value is a positive offset from the opcode of the node containing it. + * An operand, if any, simply follows the node. (Note that much of the + * code generation knows about this implicit relationship.) + * + * Using two bytes for the "next" pointer is vast overkill for most things, + * but allows patterns to get big without disasters. + * + * [The "next" pointer is always aligned on an even + * boundary, and reads the offset directly as a short. Also, there is no + * special test to reverse the sign of BACK pointers since the offset is + * stored negative.] + */ + +struct regnode_string { + U8 flags; + U8 type; + U16 next_off; + U8 string[1]; +}; + +struct regnode_1 { + U8 flags; + U8 type; + U16 next_off; + U32 arg1; +}; + +struct regnode_2 { + U8 flags; + U8 type; + U16 next_off; + U16 arg1; + U16 arg2; +}; + +/* XXX fix this description. + Impose a limit of REG_INFTY on various pattern matching operations + to limit stack growth and to avoid "infinite" recursions. +*/ +/* The default size for REG_INFTY is I16_MAX, which is the same as + SHORT_MAX (see perl.h). Unfortunately I16 isn't necessarily 16 bits + (see handy.h). On the Cray C90, sizeof(short)==4 and hence I16_MAX is + ((1<<31)-1), while on the Cray T90, sizeof(short)==8 and I16_MAX is + ((1<<63)-1). To limit stack growth to reasonable sizes, supply a + smaller default. + --Andy Dougherty 11 June 1998 +*/ +#if SHORTSIZE > 2 +# ifndef REG_INFTY +# define REG_INFTY ((1<<15)-1) +# endif +#endif + +#ifndef REG_INFTY +# define REG_INFTY I16_MAX +#endif + +#define ARG_VALUE(arg) (arg) +#define ARG__SET(arg,val) ((arg) = (val)) + +#define ARG(p) ARG_VALUE(ARG_LOC(p)) +#define ARG1(p) ARG_VALUE(ARG1_LOC(p)) +#define ARG2(p) ARG_VALUE(ARG2_LOC(p)) +#define ARG_SET(p, val) ARG__SET(ARG_LOC(p), (val)) +#define ARG1_SET(p, val) ARG__SET(ARG1_LOC(p), (val)) +#define ARG2_SET(p, val) ARG__SET(ARG2_LOC(p), (val)) + +#ifndef lint +# define NEXT_OFF(p) ((p)->next_off) +# define NODE_ALIGN(node) +# define NODE_ALIGN_FILL(node) ((node)->flags = 0xde) /* deadbeef */ +#else /* lint */ +# define NEXT_OFF(p) 0 +# define NODE_ALIGN(node) +# define NODE_ALIGN_FILL(node) +#endif /* lint */ + +#define SIZE_ALIGN NODE_ALIGN + +#define OP(p) ((p)->type) +#define OPERAND(p) (((struct regnode_string *)p)->string) +#define NODE_ALIGN(node) +#define ARG_LOC(p) (((struct regnode_1 *)p)->arg1) +#define ARG1_LOC(p) (((struct regnode_2 *)p)->arg1) +#define ARG2_LOC(p) (((struct regnode_2 *)p)->arg2) +#define NODE_STEP_REGNODE 1 /* sizeof(regnode)/sizeof(regnode) */ +#define EXTRA_STEP_2ARGS EXTRA_SIZE(struct regnode_2) + +#define NODE_STEP_B 4 + +#define NEXTOPER(p) ((p) + NODE_STEP_REGNODE) +#define PREVOPER(p) ((p) - NODE_STEP_REGNODE) + +#define FILL_ADVANCE_NODE(ptr, op) STMT_START { \ + (ptr)->type = op; (ptr)->next_off = 0; (ptr)++; } STMT_END +#define FILL_ADVANCE_NODE_ARG(ptr, op, arg) STMT_START { \ + ARG_SET(ptr, arg); FILL_ADVANCE_NODE(ptr, op); (ptr) += 1; } STMT_END + +#define MAGIC 0234 + +#define SIZE_ONLY (PL_regcode == &PL_regdummy) + +/* Flags for first parameter byte of ANYOF */ +#define ANYOF_INVERT 0x40 +#define ANYOF_FOLD 0x20 +#define ANYOF_LOCALE 0x10 +#define ANYOF_ISA 0x0F +#define ANYOF_ALNUML 0x08 +#define ANYOF_NALNUML 0x04 +#define ANYOF_SPACEL 0x02 +#define ANYOF_NSPACEL 0x01 + +/* Utility macros for bitmap of ANYOF */ +#define ANYOF_BYTE(p,c) (p)[1 + (((c) >> 3) & 31)] +#define ANYOF_BIT(c) (1 << ((c) & 7)) +#define ANYOF_SET(p,c) (ANYOF_BYTE(p,c) |= ANYOF_BIT(c)) +#define ANYOF_CLEAR(p,c) (ANYOF_BYTE(p,c) &= ~ANYOF_BIT(c)) +#define ANYOF_TEST(p,c) (ANYOF_BYTE(p,c) & ANYOF_BIT(c)) + +#define ANY_SKIP ((33 - 1)/sizeof(regnode) + 1) + +/* + * Utility definitions. + */ +#ifndef lint +#ifndef CHARMASK +#define UCHARAT(p) ((int)*(unsigned char *)(p)) +#else +#define UCHARAT(p) ((int)*(p)&CHARMASK) +#endif +#else /* lint */ +#define UCHARAT(p) PL_regdummy +#endif /* lint */ + +#define FAIL(m) croak ("/%.127s/: %s", PL_regprecomp,m) +#define FAIL2(pat,m) re_croak2("/%.127s/: ",pat,PL_regprecomp,m) + +#define EXTRA_SIZE(guy) ((sizeof(guy)-1)/sizeof(struct regnode)) + +#define REG_SEEN_ZERO_LEN 1 +#define REG_SEEN_LOOKBEHIND 2 +#define REG_SEEN_GPOS 4 +#define REG_SEEN_EVAL 8 + +#include "regnodes.h" + +/* The following have no fixed length. char* since we do strchr on it. */ +#ifndef DOINIT +EXTCONST char varies[]; +#else +EXTCONST char varies[] = { + BRANCH, BACK, STAR, PLUS, CURLY, CURLYX, REF, REFF, REFFL, + WHILEM, CURLYM, CURLYN, BRANCHJ, IFTHEN, SUSPEND, 0 +}; +#endif + +/* The following always have a length of 1. char* since we do strchr on it. */ +#ifndef DOINIT +EXTCONST char simple[]; +#else +EXTCONST char simple[] = { + ANY, SANY, ANYOF, + ALNUM, ALNUML, NALNUM, NALNUML, + SPACE, SPACEL, NSPACE, NSPACEL, + DIGIT, NDIGIT, 0 +}; +#endif + |