Add Documentation for DOES()
[perl.git] / xsutils.c
1 /*    xsutils.c
2  *
3  *    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
4  *    by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10
11 /*
12  * "Perilous to us all are the devices of an art deeper than we possess
13  * ourselves." --Gandalf
14  */
15
16
17 #include "EXTERN.h"
18 #define PERL_IN_XSUTILS_C
19 #include "perl.h"
20
21 /*
22  * Contributed by Spider Boardman (spider.boardman@orb.nashua.nh.us).
23  */
24
25 /* package attributes; */
26 PERL_XS_EXPORT_C void XS_attributes__warn_reserved(pTHX_ CV *cv);
27 PERL_XS_EXPORT_C void XS_attributes_reftype(pTHX_ CV *cv);
28 PERL_XS_EXPORT_C void XS_attributes__modify_attrs(pTHX_ CV *cv);
29 PERL_XS_EXPORT_C void XS_attributes__guess_stash(pTHX_ CV *cv);
30 PERL_XS_EXPORT_C void XS_attributes__fetch_attrs(pTHX_ CV *cv);
31 PERL_XS_EXPORT_C void XS_attributes_bootstrap(pTHX_ CV *cv);
32
33
34 /*
35  * Note that only ${pkg}::bootstrap definitions should go here.
36  * This helps keep down the start-up time, which is especially
37  * relevant for users who don't invoke any features which are
38  * (partially) implemented here.
39  *
40  * The various bootstrap definitions can take care of doing
41  * package-specific newXS() calls.  Since the layout of the
42  * bundled *.pm files is in a version-specific directory,
43  * version checks in these bootstrap calls are optional.
44  */
45
46 static const char file[] = __FILE__;
47
48 void
49 Perl_boot_core_xsutils(pTHX)
50 {
51     newXS("attributes::bootstrap",      XS_attributes_bootstrap,        file);
52 }
53
54 #include "XSUB.h"
55
56 static int
57 modify_SV_attributes(pTHX_ SV *sv, SV **retlist, SV **attrlist, int numattrs)
58 {
59     dVAR;
60     SV *attr;
61     int nret;
62
63     for (nret = 0 ; numattrs && (attr = *attrlist++); numattrs--) {
64         STRLEN len;
65         const char *name = SvPV_const(attr, len);
66         const bool negated = (*name == '-');
67
68         if (negated) {
69             name++;
70             len--;
71         }
72         switch (SvTYPE(sv)) {
73         case SVt_PVCV:
74             switch ((int)len) {
75 #ifdef CVf_ASSERTION
76             case 9:
77                 if (memEQ(name, "assertion", 9)) {
78                     if (negated)
79                         CvFLAGS((CV*)sv) &= ~CVf_ASSERTION;
80                     else
81                         CvFLAGS((CV*)sv) |= CVf_ASSERTION;
82                     continue;
83                 }
84                 break;
85 #endif
86             case 6:
87                 switch (name[3]) {
88                 case 'l':
89 #ifdef CVf_LVALUE
90                     if (memEQ(name, "lvalue", 6)) {
91                         if (negated)
92                             CvFLAGS((CV*)sv) &= ~CVf_LVALUE;
93                         else
94                             CvFLAGS((CV*)sv) |= CVf_LVALUE;
95                         continue;
96                     }
97                     break;
98                 case 'k':
99 #endif /* defined CVf_LVALUE */
100                     if (memEQ(name, "locked", 6)) {
101                         if (negated)
102                             CvFLAGS((CV*)sv) &= ~CVf_LOCKED;
103                         else
104                             CvFLAGS((CV*)sv) |= CVf_LOCKED;
105                         continue;
106                     }
107                     break;
108                 case 'h':
109                     if (memEQ(name, "method", 6)) {
110                         if (negated)
111                             CvFLAGS((CV*)sv) &= ~CVf_METHOD;
112                         else
113                             CvFLAGS((CV*)sv) |= CVf_METHOD;
114                         continue;
115                     }
116                     break;
117                 }
118                 break;
119             }
120             break;
121         default:
122             switch ((int)len) {
123             case 6:
124                 switch (name[5]) {
125                 case 'd':
126                     if (memEQ(name, "share", 5)) {
127                         if (negated)
128                             Perl_croak(aTHX_ "A variable may not be unshared");
129                         SvSHARE(sv);
130                         continue;
131                     }
132                     break;
133                 case 'e':
134                     if (memEQ(name, "uniqu", 5)) {
135                         if (SvTYPE(sv) == SVt_PVGV) {
136                             if (negated) {
137                                 GvUNIQUE_off(sv);
138                             } else {
139                                 GvUNIQUE_on(sv);
140                             }
141                         }
142                         /* Hope this came from toke.c if not a GV. */
143                         continue;
144                     }
145                 }
146             }
147             break;
148         }
149         /* anything recognized had a 'continue' above */
150         *retlist++ = attr;
151         nret++;
152     }
153
154     return nret;
155 }
156
157
158
159 /* package attributes; */
160
161 XS(XS_attributes_bootstrap)
162 {
163     dVAR;
164     dXSARGS;
165
166     if( items > 1 )
167         Perl_croak(aTHX_ "Usage: attributes::bootstrap $module");
168
169     newXSproto("attributes::_warn_reserved", XS_attributes__warn_reserved, file, "");
170     newXS("attributes::_modify_attrs",  XS_attributes__modify_attrs,    file);
171     newXSproto("attributes::_guess_stash", XS_attributes__guess_stash, file, "$");
172     newXSproto("attributes::_fetch_attrs", XS_attributes__fetch_attrs, file, "$");
173     newXSproto("attributes::reftype",   XS_attributes_reftype,  file, "$");
174
175     XSRETURN(0);
176 }
177
178 XS(XS_attributes__modify_attrs)
179 {
180     dVAR;
181     dXSARGS;
182     SV *rv, *sv;
183
184     if (items < 1) {
185 usage:
186         Perl_croak(aTHX_
187                    "Usage: attributes::_modify_attrs $reference, @attributes");
188     }
189
190     rv = ST(0);
191     if (!(SvOK(rv) && SvROK(rv)))
192         goto usage;
193     sv = SvRV(rv);
194     if (items > 1)
195         XSRETURN(modify_SV_attributes(aTHX_ sv, &ST(0), &ST(1), items-1));
196
197     XSRETURN(0);
198 }
199
200 XS(XS_attributes__fetch_attrs)
201 {
202     dVAR;
203     dXSARGS;
204     SV *rv, *sv;
205     cv_flags_t cvflags;
206
207     if (items != 1) {
208 usage:
209         Perl_croak(aTHX_
210                    "Usage: attributes::_fetch_attrs $reference");
211     }
212
213     rv = ST(0);
214     SP -= items;
215     if (!(SvOK(rv) && SvROK(rv)))
216         goto usage;
217     sv = SvRV(rv);
218
219     switch (SvTYPE(sv)) {
220     case SVt_PVCV:
221         cvflags = CvFLAGS((CV*)sv);
222         if (cvflags & CVf_LOCKED)
223             XPUSHs(sv_2mortal(newSVpvs("locked")));
224 #ifdef CVf_LVALUE
225         if (cvflags & CVf_LVALUE)
226             XPUSHs(sv_2mortal(newSVpvs("lvalue")));
227 #endif
228         if (cvflags & CVf_METHOD)
229             XPUSHs(sv_2mortal(newSVpvs("method")));
230         if (GvUNIQUE(CvGV((CV*)sv)))
231             XPUSHs(sv_2mortal(newSVpvs("unique")));
232         if (cvflags & CVf_ASSERTION)
233             XPUSHs(sv_2mortal(newSVpvs("assertion")));
234         break;
235     case SVt_PVGV:
236         if (GvUNIQUE(sv))
237             XPUSHs(sv_2mortal(newSVpvs("unique")));
238         break;
239     default:
240         break;
241     }
242
243     PUTBACK;
244 }
245
246 XS(XS_attributes__guess_stash)
247 {
248     dVAR;
249     dXSARGS;
250     SV *rv, *sv;
251     dXSTARG;
252
253     if (items != 1) {
254 usage:
255         Perl_croak(aTHX_
256                    "Usage: attributes::_guess_stash $reference");
257     }
258
259     rv = ST(0);
260     ST(0) = TARG;
261     if (!(SvOK(rv) && SvROK(rv)))
262         goto usage;
263     sv = SvRV(rv);
264
265     if (SvOBJECT(sv))
266         sv_setpvn(TARG, HvNAME_get(SvSTASH(sv)), HvNAMELEN_get(SvSTASH(sv)));
267 #if 0   /* this was probably a bad idea */
268     else if (SvPADMY(sv))
269         sv_setsv(TARG, &PL_sv_no);      /* unblessed lexical */
270 #endif
271     else {
272         const HV *stash = NULL;
273         switch (SvTYPE(sv)) {
274         case SVt_PVCV:
275             if (CvGV(sv) && isGV(CvGV(sv)) && GvSTASH(CvGV(sv)))
276                 stash = GvSTASH(CvGV(sv));
277             else if (/* !CvANON(sv) && */ CvSTASH(sv))
278                 stash = CvSTASH(sv);
279             break;
280         case SVt_PVGV:
281             if (GvGP(sv) && GvESTASH((GV*)sv))
282                 stash = GvESTASH((GV*)sv);
283             break;
284         default:
285             break;
286         }
287         if (stash)
288             sv_setpvn(TARG, HvNAME_get(stash), HvNAMELEN_get(stash));
289     }
290
291     SvSETMAGIC(TARG);
292     XSRETURN(1);
293 }
294
295 XS(XS_attributes_reftype)
296 {
297     dVAR;
298     dXSARGS;
299     SV *rv, *sv;
300     dXSTARG;
301
302     if (items != 1) {
303 usage:
304         Perl_croak(aTHX_
305                    "Usage: attributes::reftype $reference");
306     }
307
308     rv = ST(0);
309     ST(0) = TARG;
310     SvGETMAGIC(rv);
311     if (!(SvOK(rv) && SvROK(rv)))
312         goto usage;
313     sv = SvRV(rv);
314     sv_setpv(TARG, sv_reftype(sv, 0));
315     SvSETMAGIC(TARG);
316
317     XSRETURN(1);
318 }
319
320 XS(XS_attributes__warn_reserved)
321 {
322     dVAR;
323     dXSARGS;
324
325     if (items != 0) {
326         Perl_croak(aTHX_
327                    "Usage: attributes::_warn_reserved ()");
328     }
329
330     EXTEND(SP,1);
331     ST(0) = boolSV(ckWARN(WARN_RESERVED));
332
333     XSRETURN(1);
334 }
335
336 /*
337  * Local variables:
338  * c-indentation-style: bsd
339  * c-basic-offset: 4
340  * indent-tabs-mode: t
341  * End:
342  *
343  * ex: set ts=8 sts=4 sw=4 noet:
344  */