Cope with a <db.h> that isn't related to DB
[p5sagit/p5-mst-13.2.git] / ext / Opcode / Opcode.xs
CommitLineData
6badd1a5 1#include "EXTERN.h"
2#include "perl.h"
3#include "XSUB.h"
4
5/* maxo shouldn't differ from MAXO but leave room anyway (see BOOT:) */
6#define OP_MASK_BUF_SIZE (MAXO + 100)
7
8static HV *op_named_bits; /* cache shared for whole process */
9static SV *opset_all; /* mask with all bits set */
10static IV opset_len; /* length of opmasks in bytes */
11static int opcode_debug = 0;
12
13static SV *new_opset _((SV *old_opset));
14static int verify_opset _((SV *opset, int fatal));
15static void set_opset_bits _((char *bitmap, SV *bitspec, int on, char *opname));
16static void put_op_bitspec _((char *optag, STRLEN len, SV *opset));
17static SV *get_op_bitspec _((char *opname, STRLEN len, int fatal));
18
19
20/* Initialise our private op_named_bits HV.
21 * It is first loaded with the name and number of each perl operator.
22 * Then the builtin tags :none and :all are added.
23 * Opcode.pm loads the standard optags from __DATA__
24 */
25
26static void
27op_names_init()
28{
29 int i;
30 STRLEN len;
31 char *opname;
32 char *bitmap;
33
34 op_named_bits = newHV();
35 for(i=0; i < maxo; ++i) {
36 hv_store(op_named_bits, op_name[i],strlen(op_name[i]),
37 Sv=newSViv(i), 0);
38 SvREADONLY_on(Sv);
39 }
40
41 put_op_bitspec(":none",0, sv_2mortal(new_opset(Nullsv)));
42
43 opset_all = new_opset(Nullsv);
44 bitmap = SvPV(opset_all, len);
45 i = len-1; /* deal with last byte specially, see below */
46 while(i-- > 0)
47 bitmap[i] = 0xFF;
48 /* Take care to set the right number of bits in the last byte */
8903cb82 49 bitmap[len-1] = (maxo & 0x07) ? ~(0xFF << (maxo & 0x07)) : 0xFF;
6badd1a5 50 put_op_bitspec(":all",0, opset_all); /* don't mortalise */
51}
52
53
54/* Store a new tag definition. Always a mask.
55 * The tag must not already be defined.
56 * SV *mask is copied not referenced.
57 */
58
59static void
60put_op_bitspec(optag, len, mask)
61 char *optag;
62 STRLEN len;
63 SV *mask;
64{
65 SV **svp;
66 verify_opset(mask,1);
67 if (!len)
68 len = strlen(optag);
69 svp = hv_fetch(op_named_bits, optag, len, 1);
70 if (SvOK(*svp))
71 croak("Opcode tag \"%s\" already defined", optag);
72 sv_setsv(*svp, mask);
73 SvREADONLY_on(*svp);
74}
75
76
77
78/* Fetch a 'bits' entry for an opname or optag (IV/PV).
79 * Note that we return the actual entry for speed.
80 * Always sv_mortalcopy() if returing it to user code.
81 */
82
83static SV *
84get_op_bitspec(opname, len, fatal)
85 char *opname;
86 STRLEN len;
87 int fatal;
88{
89 SV **svp;
90 if (!len)
91 len = strlen(opname);
92 svp = hv_fetch(op_named_bits, opname, len, 0);
93 if (!svp || !SvOK(*svp)) {
94 if (!fatal)
95 return Nullsv;
96 if (*opname == ':')
97 croak("Unknown operator tag \"%s\"", opname);
98 if (*opname == '!') /* XXX here later, or elsewhere? */
99 croak("Can't negate operators here (\"%s\")", opname);
100 if (isALPHA(*opname))
101 croak("Unknown operator name \"%s\"", opname);
102 croak("Unknown operator prefix \"%s\"", opname);
103 }
104 return *svp;
105}
106
107
108
109static SV *
110new_opset(old_opset)
111 SV *old_opset;
112{
113 SV *opset;
114 if (old_opset) {
115 verify_opset(old_opset,1);
116 opset = newSVsv(old_opset);
117 }
118 else {
119 opset = newSV(opset_len);
120 Zero(SvPVX(opset), opset_len, char);
121 SvCUR_set(opset, opset_len);
122 (void)SvPOK_only(opset);
123 }
124 /* not mortalised here */
125 return opset;
126}
127
128
129static int
130verify_opset(opset, fatal)
131 SV *opset;
132 int fatal;
133{
134 char *err = Nullch;
135 if (!SvOK(opset)) err = "undefined";
136 else if (!SvPOK(opset)) err = "wrong type";
137 else if (SvCUR(opset) != opset_len) err = "wrong size";
138 if (err && fatal) {
139 croak("Invalid opset: %s", err);
140 }
141 return !err;
142}
143
144
145static void
146set_opset_bits(bitmap, bitspec, on, opname)
147 char *bitmap;
148 SV *bitspec;
149 int on;
150 char *opname;
151{
152 if (SvIOK(bitspec)) {
153 int myopcode = SvIV(bitspec);
154 int offset = myopcode >> 3;
155 int bit = myopcode & 0x07;
156 if (myopcode >= maxo || myopcode < 0)
157 croak("panic: opcode \"%s\" value %d is invalid", opname, myopcode);
158 if (opcode_debug >= 2)
ff0cee69 159 warn("set_opset_bits bit %2d (off=%d, bit=%d) %s %s\n",
6badd1a5 160 myopcode, offset, bit, opname, (on)?"on":"off");
161 if (on)
162 bitmap[offset] |= 1 << bit;
163 else
164 bitmap[offset] &= ~(1 << bit);
165 }
166 else if (SvPOK(bitspec) && SvCUR(bitspec) == opset_len) {
167
168 STRLEN len;
169 char *specbits = SvPV(bitspec, len);
170 if (opcode_debug >= 2)
171 warn("set_opset_bits opset %s %s\n", opname, (on)?"on":"off");
172 if (on)
173 while(len-- > 0) bitmap[len] |= specbits[len];
174 else
175 while(len-- > 0) bitmap[len] &= ~specbits[len];
176 }
177 else
ff0cee69 178 croak("panic: invalid bitspec for \"%s\" (type %u)",
179 opname, (unsigned)SvTYPE(bitspec));
6badd1a5 180}
181
182
183static void
184opmask_add(opset) /* THE ONLY FUNCTION TO EDIT op_mask ITSELF */
185 SV *opset;
186{
187 int i,j;
188 char *bitmask;
189 STRLEN len;
190 int myopcode = 0;
191
192 verify_opset(opset,1); /* croaks on bad opset */
193
194 if (!op_mask) /* caller must ensure op_mask exists */
195 croak("Can't add to uninitialised op_mask");
196
197 /* OPCODES ALREADY MASKED ARE NEVER UNMASKED. See opmask_addlocal() */
198
199 bitmask = SvPV(opset, len);
200 for (i=0; i < opset_len; i++) {
201 U16 bits = bitmask[i];
202 if (!bits) { /* optimise for sparse masks */
203 myopcode += 8;
204 continue;
205 }
206 for (j=0; j < 8 && myopcode < maxo; )
207 op_mask[myopcode++] |= bits & (1 << j++);
208 }
209}
210
211static void
212opmask_addlocal(opset, op_mask_buf) /* Localise op_mask then opmask_add() */
213 SV *opset;
214 char *op_mask_buf;
215{
216 char *orig_op_mask = op_mask;
217 SAVEPPTR(op_mask);
218 if (opcode_debug >= 2)
219 SAVEDESTRUCTOR((void(*)_((void*)))warn,"op_mask restored");
220 op_mask = &op_mask_buf[0];
221 if (orig_op_mask)
222 Copy(orig_op_mask, op_mask, maxo, char);
223 else
224 Zero(op_mask, maxo, char);
225 opmask_add(opset);
226}
227
228
229
230MODULE = Opcode PACKAGE = Opcode
231
232PROTOTYPES: ENABLE
233
234BOOT:
235 assert(maxo < OP_MASK_BUF_SIZE);
760ac839 236 opset_len = (maxo + 7) / 8;
6badd1a5 237 if (opcode_debug >= 1)
ff0cee69 238 warn("opset_len %ld\n", (long)opset_len);
6badd1a5 239 op_names_init();
240
241
242void
243_safe_call_sv(package, mask, codesv)
244 char * package
245 SV * mask
246 SV * codesv
247 PPCODE:
248 char op_mask_buf[OP_MASK_BUF_SIZE];
249 GV *gv;
250
251 ENTER;
252
253 opmask_addlocal(mask, op_mask_buf);
254
255 save_aptr(&endav);
256 endav = (AV*)sv_2mortal((SV*)newAV()); /* ignore END blocks for now */
257
258 save_hptr(&defstash); /* save current default stack */
259 /* the assignment to global defstash changes our sense of 'main' */
260 defstash = gv_stashpv(package, GV_ADDWARN); /* should exist already */
261
262 /* defstash must itself contain a main:: so we'll add that now */
263 /* take care with the ref counts (was cause of long standing bug) */
264 /* XXX I'm still not sure if this is right, GV_ADDWARN should warn! */
265 gv = gv_fetchpv("main::", GV_ADDWARN, SVt_PVHV);
266 sv_free((SV*)GvHV(gv));
267 GvHV(gv) = (HV*)SvREFCNT_inc(defstash);
268
269 PUSHMARK(sp);
270 perl_call_sv(codesv, GIMME|G_EVAL|G_KEEPERR); /* use callers context */
271 SPAGAIN; /* for the PUTBACK added by xsubpp */
272 LEAVE;
273
274
275int
276verify_opset(opset, fatal = 0)
277 SV *opset
278 int fatal
279
280
281void
282invert_opset(opset)
283 SV *opset
284 CODE:
285 {
286 char *bitmap;
287 STRLEN len = opset_len;
288 opset = new_opset(opset); /* verify and clone opset */
289 bitmap = SvPVX(opset);
290 while(len-- > 0)
291 bitmap[len] = ~bitmap[len];
292 /* take care of extra bits beyond maxo in last byte */
8903cb82 293 if (maxo & 07)
294 bitmap[opset_len-1] &= ~(0xFF << (maxo & 0x07));
6badd1a5 295 }
296 ST(0) = opset;
297
298
299void
300opset_to_ops(opset, desc = 0)
301 SV *opset
302 int desc
303 PPCODE:
304 {
305 STRLEN len;
306 int i, j, myopcode;
307 char *bitmap = SvPV(opset, len);
308 char **names = (desc) ? op_desc : op_name;
309 verify_opset(opset,1);
310 for (myopcode=0, i=0; i < opset_len; i++) {
311 U16 bits = bitmap[i];
312 for (j=0; j < 8 && myopcode < maxo; j++, myopcode++) {
313 if ( bits & (1 << j) )
314 XPUSHs(sv_2mortal(newSVpv(names[myopcode], 0)));
315 }
316 }
317 }
318
319
320void
321opset(...)
322 CODE:
323 int i, j;
324 SV *bitspec, *opset;
325 char *bitmap;
326 STRLEN len, on;
327 opset = new_opset(Nullsv);
328 bitmap = SvPVX(opset);
329 for (i = 0; i < items; i++) {
330 char *opname;
331 on = 1;
332 if (verify_opset(ST(i),0)) {
333 opname = "(opset)";
334 bitspec = ST(i);
335 }
336 else {
337 opname = SvPV(ST(i), len);
338 if (*opname == '!') { on=0; ++opname;--len; }
339 bitspec = get_op_bitspec(opname, len, 1);
340 }
341 set_opset_bits(bitmap, bitspec, on, opname);
342 }
343 ST(0) = opset;
344
345
346#define PERMITING (ix == 0 || ix == 1)
347#define ONLY_THESE (ix == 0 || ix == 2)
348
349void
350permit_only(safe, ...)
351 SV *safe
352 ALIAS:
353 permit = 1
354 deny_only = 2
355 deny = 3
356 CODE:
357 int i, on;
358 SV *bitspec, *mask;
359 char *bitmap, *opname;
360 STRLEN len;
361
362 if (!SvROK(safe) || !SvOBJECT(SvRV(safe)) || SvTYPE(SvRV(safe))!=SVt_PVHV)
363 croak("Not a Safe object");
364 mask = *hv_fetch((HV*)SvRV(safe), "Mask",4, 1);
365 if (ONLY_THESE) /* *_only = new mask, else edit current */
366 sv_setsv(mask, new_opset(PERMITING ? opset_all : Nullsv));
367 else verify_opset(mask,1); /* croaks */
368 bitmap = SvPVX(mask);
369 for (i = 1; i < items; i++) {
370 on = PERMITING ? 0 : 1; /* deny = mask bit on */
371 if (verify_opset(ST(i),0)) { /* it's a valid mask */
372 opname = "(opset)";
373 bitspec = ST(i);
374 }
375 else { /* it's an opname/optag */
376 opname = SvPV(ST(i), len);
377 /* invert if op has ! prefix (only one allowed) */
378 if (*opname == '!') { on = !on; ++opname; --len; }
379 bitspec = get_op_bitspec(opname, len, 1); /* croaks */
380 }
381 set_opset_bits(bitmap, bitspec, on, opname);
382 }
383 ST(0) = &sv_yes;
384
385
386
387void
388opdesc(...)
389 PPCODE:
390 int i, myopcode;
391 STRLEN len;
392 SV **args;
393 /* copy args to a scratch area since we may push output values onto */
394 /* the stack faster than we read values off it if masks are used. */
395 args = (SV**)SvPVX(sv_2mortal(newSVpv((char*)&ST(0), items*sizeof(SV*))));
396 for (i = 0; i < items; i++) {
397 char *opname = SvPV(args[i], len);
398 SV *bitspec = get_op_bitspec(opname, len, 1);
399 if (SvIOK(bitspec)) {
400 myopcode = SvIV(bitspec);
401 if (myopcode < 0 || myopcode >= maxo)
402 croak("panic: opcode %d (%s) out of range",myopcode,opname);
403 XPUSHs(sv_2mortal(newSVpv(op_desc[myopcode], 0)));
404 }
405 else if (SvPOK(bitspec) && SvCUR(bitspec) == opset_len) {
406 int b, j;
407 char *bitmap = SvPV(bitspec,na);
408 myopcode = 0;
409 for (b=0; b < opset_len; b++) {
410 U16 bits = bitmap[b];
411 for (j=0; j < 8 && myopcode < maxo; j++, myopcode++)
412 if (bits & (1 << j))
413 XPUSHs(sv_2mortal(newSVpv(op_desc[myopcode], 0)));
414 }
415 }
416 else
ff0cee69 417 croak("panic: invalid bitspec for \"%s\" (type %u)",
418 opname, (unsigned)SvTYPE(bitspec));
6badd1a5 419 }
420
421
422void
423define_optag(optagsv, mask)
424 SV *optagsv
425 SV *mask
426 CODE:
427 STRLEN len;
428 char *optag = SvPV(optagsv, len);
429 put_op_bitspec(optag, len, mask); /* croaks */
430 ST(0) = &sv_yes;
431
432
433void
434empty_opset()
435 CODE:
436 ST(0) = sv_2mortal(new_opset(Nullsv));
437
438void
439full_opset()
440 CODE:
441 ST(0) = sv_2mortal(new_opset(opset_all));
442
443void
444opmask_add(opset)
445 SV *opset
446 PREINIT:
447 if (!op_mask)
448 Newz(0, op_mask, maxo, char);
449
450void
451opcodes()
452 PPCODE:
453 if (GIMME == G_ARRAY) {
454 croak("opcodes in list context not yet implemented"); /* XXX */
455 }
456 else {
457 XPUSHs(sv_2mortal(newSViv(maxo)));
458 }
459
460void
461opmask()
462 CODE:
463 ST(0) = sv_2mortal(new_opset(Nullsv));
464 if (op_mask) {
465 char *bitmap = SvPVX(ST(0));
466 int myopcode;
467 for(myopcode=0; myopcode < maxo; ++myopcode) {
468 if (op_mask[myopcode])
469 bitmap[myopcode >> 3] |= 1 << (myopcode & 0x07);
470 }
471 }
472