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[perl5.git] / regcomp.h
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a0d0e21e 1/* regcomp.h
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2 */
3
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4typedef OP OP_4tree; /* Will be redefined later. */
5
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6/*
7 * The "internal use only" fields in regexp.h are present to pass info from
8 * compile to execute that permits the execute phase to run lots faster on
9 * simple cases. They are:
10 *
79072805 11 * regstart sv that must begin a match; Nullch if none obvious
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12 * reganch is the match anchored (at beginning-of-line only)?
13 * regmust string (pointer into program) that match must include, or NULL
79072805 14 * [regmust changed to SV* for bminstr()--law]
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15 * regmlen length of regmust string
16 * [regmlen not used currently]
17 *
18 * Regstart and reganch permit very fast decisions on suitable starting points
19 * for a match, cutting down the work a lot. Regmust permits fast rejection
20 * of lines that cannot possibly match. The regmust tests are costly enough
e50aee73 21 * that pregcomp() supplies a regmust only if the r.e. contains something
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22 * potentially expensive (at present, the only such thing detected is * or +
23 * at the start of the r.e., which can involve a lot of backup). Regmlen is
e50aee73 24 * supplied because the test in pregexec() needs it and pregcomp() is computing
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25 * it anyway.
26 * [regmust is now supplied always. The tests that use regmust have a
27 * heuristic that disables the test if it usually matches.]
28 *
29 * [In fact, we now use regmust in many cases to locate where the search
30 * starts in the string, so if regback is >= 0, the regmust search is never
31 * wasted effort. The regback variable says how many characters back from
32 * where regmust matched is the earliest possible start of the match.
33 * For instance, /[a-z].foo/ has a regmust of 'foo' and a regback of 2.]
34 */
35
36/*
37 * Structure for regexp "program". This is essentially a linear encoding
38 * of a nondeterministic finite-state machine (aka syntax charts or
39 * "railroad normal form" in parsing technology). Each node is an opcode
40 * plus a "next" pointer, possibly plus an operand. "Next" pointers of
41 * all nodes except BRANCH implement concatenation; a "next" pointer with
42 * a BRANCH on both ends of it is connecting two alternatives. (Here we
43 * have one of the subtle syntax dependencies: an individual BRANCH (as
44 * opposed to a collection of them) is never concatenated with anything
45 * because of operator precedence.) The operand of some types of node is
46 * a literal string; for others, it is a node leading into a sub-FSM. In
47 * particular, the operand of a BRANCH node is the first node of the branch.
48 * (NB this is *not* a tree structure: the tail of the branch connects
49 * to the thing following the set of BRANCHes.) The opcodes are:
50 */
51
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52/*
53 * A node is one char of opcode followed by two chars of "next" pointer.
54 * "Next" pointers are stored as two 8-bit pieces, high order first. The
55 * value is a positive offset from the opcode of the node containing it.
56 * An operand, if any, simply follows the node. (Note that much of the
57 * code generation knows about this implicit relationship.)
58 *
59 * Using two bytes for the "next" pointer is vast overkill for most things,
60 * but allows patterns to get big without disasters.
61 *
e91177ed 62 * [The "next" pointer is always aligned on an even
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63 * boundary, and reads the offset directly as a short. Also, there is no
64 * special test to reverse the sign of BACK pointers since the offset is
65 * stored negative.]
66 */
67
c277df42 68struct regnode_string {
cd439c50 69 U8 str_len;
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70 U8 type;
71 U16 next_off;
cd439c50 72 char string[1];
c277df42 73};
a687059c 74
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75struct regnode_1 {
76 U8 flags;
77 U8 type;
78 U16 next_off;
79 U32 arg1;
80};
81
82struct regnode_2 {
83 U8 flags;
84 U8 type;
85 U16 next_off;
86 U16 arg1;
87 U16 arg2;
88};
89
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90#define ANYOF_BITMAP_SIZE 32 /* 256 b/(8 b/B) */
91#define ANYOF_CLASSBITMAP_SIZE 4
92
93struct regnode_charclass {
94 U8 flags;
95 U8 type;
96 U16 next_off;
97 char bitmap[ANYOF_BITMAP_SIZE];
98};
99
100struct regnode_charclass_class {
101 U8 flags;
102 U8 type;
103 U16 next_off;
104 char bitmap[ANYOF_BITMAP_SIZE];
105 char classflags[ANYOF_CLASSBITMAP_SIZE];
106};
107
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108/* XXX fix this description.
109 Impose a limit of REG_INFTY on various pattern matching operations
110 to limit stack growth and to avoid "infinite" recursions.
111*/
112/* The default size for REG_INFTY is I16_MAX, which is the same as
113 SHORT_MAX (see perl.h). Unfortunately I16 isn't necessarily 16 bits
114 (see handy.h). On the Cray C90, sizeof(short)==4 and hence I16_MAX is
115 ((1<<31)-1), while on the Cray T90, sizeof(short)==8 and I16_MAX is
116 ((1<<63)-1). To limit stack growth to reasonable sizes, supply a
117 smaller default.
118 --Andy Dougherty 11 June 1998
119*/
120#if SHORTSIZE > 2
121# ifndef REG_INFTY
122# define REG_INFTY ((1<<15)-1)
123# endif
124#endif
125
126#ifndef REG_INFTY
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127# define REG_INFTY I16_MAX
128#endif
a687059c 129
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130#define ARG_VALUE(arg) (arg)
131#define ARG__SET(arg,val) ((arg) = (val))
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132
133#define ARG(p) ARG_VALUE(ARG_LOC(p))
134#define ARG1(p) ARG_VALUE(ARG1_LOC(p))
135#define ARG2(p) ARG_VALUE(ARG2_LOC(p))
136#define ARG_SET(p, val) ARG__SET(ARG_LOC(p), (val))
137#define ARG1_SET(p, val) ARG__SET(ARG1_LOC(p), (val))
138#define ARG2_SET(p, val) ARG__SET(ARG2_LOC(p), (val))
139
140#ifndef lint
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141# define NEXT_OFF(p) ((p)->next_off)
142# define NODE_ALIGN(node)
143# define NODE_ALIGN_FILL(node) ((node)->flags = 0xde) /* deadbeef */
a687059c 144#else /* lint */
c277df42 145# define NEXT_OFF(p) 0
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146# define NODE_ALIGN(node)
147# define NODE_ALIGN_FILL(node)
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148#endif /* lint */
149
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150#define SIZE_ALIGN NODE_ALIGN
151
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152#define OP(p) ((p)->type)
153#define OPERAND(p) (((struct regnode_string *)p)->string)
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154#define MASK(p) ((char*)OPERAND(p))
155#define STR_LEN(p) (((struct regnode_string *)p)->str_len)
156#define STRING(p) (((struct regnode_string *)p)->string)
157#define STR_SZ(l) ((l + sizeof(regnode) - 1) / sizeof(regnode))
158#define NODE_SZ_STR(p) (STR_SZ(STR_LEN(p))+1)
159
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160#define NODE_ALIGN(node)
161#define ARG_LOC(p) (((struct regnode_1 *)p)->arg1)
162#define ARG1_LOC(p) (((struct regnode_2 *)p)->arg1)
163#define ARG2_LOC(p) (((struct regnode_2 *)p)->arg2)
164#define NODE_STEP_REGNODE 1 /* sizeof(regnode)/sizeof(regnode) */
165#define EXTRA_STEP_2ARGS EXTRA_SIZE(struct regnode_2)
166
167#define NODE_STEP_B 4
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168
169#define NEXTOPER(p) ((p) + NODE_STEP_REGNODE)
170#define PREVOPER(p) ((p) - NODE_STEP_REGNODE)
171
e91177ed 172#define FILL_ADVANCE_NODE(ptr, op) STMT_START { \
c277df42 173 (ptr)->type = op; (ptr)->next_off = 0; (ptr)++; } STMT_END
e91177ed 174#define FILL_ADVANCE_NODE_ARG(ptr, op, arg) STMT_START { \
c277df42 175 ARG_SET(ptr, arg); FILL_ADVANCE_NODE(ptr, op); (ptr) += 1; } STMT_END
a687059c 176
22c35a8c 177#define REG_MAGIC 0234
a687059c 178
3280af22 179#define SIZE_ONLY (PL_regcode == &PL_regdummy)
c277df42 180
936ed897 181/* Flags for node->flags of ANYOF */
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182
183#define ANYOF_CLASS 0x08
184#define ANYOF_INVERT 0x04
185#define ANYOF_FOLD 0x02
186#define ANYOF_LOCALE 0x01
187
936ed897 188/* Character classes for node->classflags of ANYOF */
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189
190#define ANYOF_ALNUM 0 /* \w, utf8::IsWord, isALNUM() */
191#define ANYOF_NALNUM 1
192#define ANYOF_SPACE 2
193#define ANYOF_NSPACE 3
194#define ANYOF_DIGIT 4
195#define ANYOF_NDIGIT 5
196#define ANYOF_ALNUMC 6 /* isalnum(3), utf8::IsAlnum, isALNUMC() */
197#define ANYOF_NALNUMC 7
198#define ANYOF_ALPHA 8
199#define ANYOF_NALPHA 9
200#define ANYOF_ASCII 10
201#define ANYOF_NASCII 11
202#define ANYOF_CNTRL 12
203#define ANYOF_NCNTRL 13
204#define ANYOF_GRAPH 14
205#define ANYOF_NGRAPH 15
206#define ANYOF_LOWER 16
207#define ANYOF_NLOWER 17
208#define ANYOF_PRINT 18
209#define ANYOF_NPRINT 19
210#define ANYOF_PUNCT 20
211#define ANYOF_NPUNCT 21
212#define ANYOF_UPPER 22
213#define ANYOF_NUPPER 23
214#define ANYOF_XDIGIT 24
215#define ANYOF_NXDIGIT 25
216
217#define ANYOF_MAX 31
218
219/* Backward source code compatibility. */
220
221#define ANYOF_ALNUML ANYOF_ALNUM
222#define ANYOF_NALNUML ANYOF_NALNUM
223#define ANYOF_SPACEL ANYOF_SPACE
224#define ANYOF_NSPACEL ANYOF_NSPACE
225
226/* Utility macros for the bitmap and classes of ANYOF */
227
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228#define ANYOF_SIZE (sizeof(struct regnode_charclass))
229#define ANYOF_CLASS_SIZE (sizeof(struct regnode_charclass_class))
b8c5462f 230
936ed897 231#define ANYOF_FLAGS(p) ((p)->flags)
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232#define ANYOF_FLAGS_ALL 0xff
233
234#define ANYOF_BIT(c) (1 << ((c) & 7))
235
936ed897 236#define ANYOF_CLASS_BYTE(p, c) (((struct regnode_charclass_class*)(p))->classflags[((c) >> 3) & 3])
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237#define ANYOF_CLASS_SET(p, c) (ANYOF_CLASS_BYTE(p, c) |= ANYOF_BIT(c))
238#define ANYOF_CLASS_CLEAR(p, c) (ANYOF_CLASS_BYTE(p, c) &= ~ANYOF_BIT(c))
239#define ANYOF_CLASS_TEST(p, c) (ANYOF_CLASS_BYTE(p, c) & ANYOF_BIT(c))
240
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241#define ANYOF_CLASS_ZERO(ret) Zero(((struct regnode_charclass_class*)(ret))->classflags, ANYOF_CLASSBITMAP_SIZE, char)
242#define ANYOF_BITMAP_ZERO(ret) Zero(((struct regnode_charclass*)(ret))->bitmap, ANYOF_BITMAP_SIZE, char)
243
244#define ANYOF_BITMAP(p) (((struct regnode_charclass*)(p))->bitmap)
245#define ANYOF_BITMAP_BYTE(p, c) (ANYOF_BITMAP(p)[((c) >> 3) & 31])
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246#define ANYOF_BITMAP_SET(p, c) (ANYOF_BITMAP_BYTE(p, c) |= ANYOF_BIT(c))
247#define ANYOF_BITMAP_CLEAR(p,c) (ANYOF_BITMAP_BYTE(p, c) &= ~ANYOF_BIT(c))
248#define ANYOF_BITMAP_TEST(p, c) (ANYOF_BITMAP_BYTE(p, c) & ANYOF_BIT(c))
249
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250#define ANYOF_SKIP ((ANYOF_SIZE - 1)/sizeof(regnode))
251#define ANYOF_CLASS_SKIP ((ANYOF_CLASS_SIZE - 1)/sizeof(regnode))
252#define ANYOF_CLASS_ADD_SKIP (ANYOF_CLASS_SKIP - ANYOF_SKIP)
c277df42 253
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254/*
255 * Utility definitions.
256 */
257#ifndef lint
2304df62 258#ifndef CHARMASK
4d61ec05 259#define UCHARAT(p) ((int)*(U8*)(p))
a687059c 260#else
2304df62 261#define UCHARAT(p) ((int)*(p)&CHARMASK)
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262#endif
263#else /* lint */
6b88bc9c 264#define UCHARAT(p) PL_regdummy
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265#endif /* lint */
266
34184a49 267#define FAIL(m) \
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268 STMT_START { \
269 if (!SIZE_ONLY) \
c76ac1ee 270 SAVEDESTRUCTOR_X(clear_re,(void*)PL_regcomp_rx); \
cea2e8a9 271 Perl_croak(aTHX_ "/%.127s/: %s", PL_regprecomp,m); \
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272 } STMT_END
273
274#define FAIL2(pat,m) \
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275 STMT_START { \
276 if (!SIZE_ONLY) \
c76ac1ee 277 SAVEDESTRUCTOR_X(clear_re,(void*)PL_regcomp_rx); \
cea2e8a9 278 S_re_croak2(aTHX_ "/%.127s/: ",pat,PL_regprecomp,m); \
34184a49 279 } STMT_END
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280
281#define EXTRA_SIZE(guy) ((sizeof(guy)-1)/sizeof(struct regnode))
282
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283#define REG_SEEN_ZERO_LEN 1
284#define REG_SEEN_LOOKBEHIND 2
285#define REG_SEEN_GPOS 4
286#define REG_SEEN_EVAL 8
287
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288START_EXTERN_C
289
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290#include "regnodes.h"
291
4d61ec05 292/* The following have no fixed length. U8 so we can do strchr() on it. */
d09b2d29 293#ifndef DOINIT
4d61ec05 294EXTCONST U8 PL_varies[];
d09b2d29 295#else
4d61ec05 296EXTCONST U8 PL_varies[] = {
d09b2d29 297 BRANCH, BACK, STAR, PLUS, CURLY, CURLYX, REF, REFF, REFFL,
a0ed51b3 298 WHILEM, CURLYM, CURLYN, BRANCHJ, IFTHEN, SUSPEND, CLUMP, 0
c277df42 299};
d09b2d29 300#endif
c277df42 301
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302/* The following always have a length of 1. U8 we can do strchr() on it. */
303/* (Note that length 1 means "one character" under UTF8, not "one octet".) */
d09b2d29 304#ifndef DOINIT
4d61ec05 305EXTCONST U8 PL_simple[];
d09b2d29 306#else
4d61ec05 307EXTCONST U8 PL_simple[] = {
22c35a8c 308 REG_ANY, ANYUTF8, SANY, SANYUTF8, ANYOF, ANYOFUTF8,
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309 ALNUM, ALNUMUTF8, ALNUML, ALNUMLUTF8,
310 NALNUM, NALNUMUTF8, NALNUML, NALNUMLUTF8,
311 SPACE, SPACEUTF8, SPACEL, SPACELUTF8,
312 NSPACE, NSPACEUTF8, NSPACEL, NSPACELUTF8,
313 DIGIT, DIGITUTF8, NDIGIT, NDIGITUTF8, 0
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314};
315#endif
316
73c4f7a1 317END_EXTERN_C
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318
319typedef struct re_scream_pos_data_s
320{
321 char **scream_olds; /* match pos */
322 I32 *scream_pos; /* Internal iterator of scream. */
323} re_scream_pos_data;
324
325struct reg_data {
326 U32 count;
327 U8 *what;
328 void* data[1];
329};
330
331struct reg_substr_datum {
332 I32 min_offset;
333 I32 max_offset;
334 SV *substr;
335};
336
337struct reg_substr_data {
338 struct reg_substr_datum data[3]; /* Actual array */
339};
340
341#define anchored_substr substrs->data[0].substr
342#define anchored_offset substrs->data[0].min_offset
343#define float_substr substrs->data[1].substr
344#define float_min_offset substrs->data[1].min_offset
345#define float_max_offset substrs->data[1].max_offset
346#define check_substr substrs->data[2].substr
347#define check_offset_min substrs->data[2].min_offset
348#define check_offset_max substrs->data[2].max_offset