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/cvs/Devel-FindRef/FindRef.xs
Revision: 1.14
Committed: Mon Dec 1 13:22:43 2008 UTC (15 years, 5 months ago) by root
Branch: MAIN
Changes since 1.13: +21 -15 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #include "EXTERN.h"
2 #include "perl.h"
3 #include "XSUB.h"
4
5 #define PERL_VERSION_ATLEAST(a,b,c) \
6 (PERL_REVISION > (a) \
7 || (PERL_REVISION == (a) \
8 && (PERL_VERSION > (b) \
9 || (PERL_VERSION == (b) && PERLSUBVERSION >= (c)))))
10
11 #if !PERL_VERSION_ATLEAST (5,8,9)
12 # define SVt_LAST 16
13 #endif
14
15 #if !PERL_VERSION_ATLEAST (5,10,0)
16 # define SvPAD_OUR(dummy) 0
17 #endif
18
19 #define res_pair(text) \
20 do { \
21 AV *av = newAV (); \
22 av_push (av, newSVpv (text, 0)); \
23 if (rmagical) SvRMAGICAL_on (sv); \
24 av_push (av, sv_rvweaken (newRV_inc (sv))); \
25 if (rmagical) SvRMAGICAL_off (sv); \
26 av_push (about, newRV_noinc ((SV *)av)); \
27 } while (0)
28
29 #define res_text(text) \
30 do { \
31 AV *av = newAV (); \
32 av_push (av, newSVpv (text, 0)); \
33 av_push (about, newRV_noinc ((SV *)av)); \
34 } while (0)
35
36 #define res_gv(sigil) \
37 res_text (form ("in the global %c%s::%.*s", sigil, \
38 HvNAME (GvSTASH (sv)), \
39 GvNAMELEN (sv), \
40 GvNAME (sv) ? GvNAME (sv) : "<anonymous>"))
41
42 MODULE = Devel::FindRef PACKAGE = Devel::FindRef
43
44 PROTOTYPES: ENABLE
45
46 void
47 find_ (SV *target)
48 PPCODE:
49 {
50 SV *arena, *targ;
51 U32 rmagical;
52 int i;
53 AV *about = newAV ();
54 AV *excl = newAV ();
55
56 if (!SvROK (target))
57 croak ("find expects a reference to a perl value");
58
59 targ = SvRV (target);
60
61 for (arena = PL_sv_arenaroot; arena; arena = SvANY (arena))
62 {
63 UV idx = SvREFCNT (arena);
64
65 /* Remember that the zeroth slot is used as the pointer onwards, so don't
66 include it. */
67 while (--idx > 0)
68 {
69 SV *sv = &arena [idx];
70
71 if (SvTYPE (sv) >= SVt_LAST)
72 continue;
73
74 /* temporarily disable RMAGICAL, it can easily interfere with us */
75 if ((rmagical = SvRMAGICAL (sv)))
76 SvRMAGICAL_off (sv);
77
78 if (SvTYPE (sv) >= SVt_PVMG)
79 {
80 if (SvTYPE (sv) == SVt_PVMG && SvPAD_OUR (sv))
81 {
82 /* I have no clue what this is */
83 /* maybe some placeholder for our variables for eval? */
84 /* it doesn't seem to reference anything, so we should be able to ignore it */
85 }
86 else
87 {
88 MAGIC *mg = SvMAGIC (sv);
89
90 while (mg)
91 {
92 if (mg->mg_obj == targ)
93 res_pair (form ("referenced (in mg_obj) by '%c' type magic attached to", mg->mg_type));
94
95 if ((SV *)mg->mg_ptr == targ && mg->mg_flags & MGf_REFCOUNTED)
96 res_pair (form ("referenced (in mg_ptr) by '%c' type magic attached to", mg->mg_type));
97
98 mg = mg->mg_moremagic;
99 }
100 }
101 }
102
103 if (SvROK (sv) && !SvWEAKREF (sv))
104 {
105 if (sv != target && SvRV (sv) == targ && !SvWEAKREF (sv))
106 res_pair ("referenced by");
107 }
108 else
109 switch (SvTYPE (sv))
110 {
111 case SVt_PVAV:
112 if (AvREAL (sv))
113 for (i = AvFILLp (sv) + 1; i--; )
114 if (AvARRAY (sv)[i] == targ)
115 res_pair (form ("in array element %d of", i));
116
117 break;
118
119 case SVt_PVHV:
120 if (hv_iterinit ((HV *)sv))
121 {
122 HE *he;
123
124 while ((he = hv_iternext ((HV *)sv)))
125 if (HeVAL (he) == targ)
126 res_pair (form ("in the member '%.*s' of", HeKLEN (he), HeKEY (he)));
127 }
128
129 break;
130
131 case SVt_PVCV:
132 {
133 int depth = CvDEPTH (sv);
134
135 /* Anonymous subs have a padlist but zero depth */
136 if (CvANON (sv) && !depth && CvPADLIST (sv))
137 depth = 1;
138
139 if (depth)
140 {
141 AV *padlist = CvPADLIST (sv);
142
143 while (depth)
144 {
145 AV *pad = (AV *)AvARRAY (padlist)[depth];
146
147 av_push (excl, newSVuv (PTR2UV (pad))); /* exclude pads themselves from being found */
148
149 /* The 0th pad slot is @_ */
150 if (AvARRAY (pad)[0] == targ)
151 res_pair ("the argument array for");
152
153 for (i = AvFILLp (pad) + 1; --i; )
154 if (AvARRAY (pad)[i] == targ)
155 {
156 /* Values from constant functions are stored in the pad without any name */
157 SV *name_sv = AvARRAY (AvARRAY (padlist)[0])[i];
158
159 if (name_sv && SvPOK (name_sv))
160 res_pair (form ("in the lexical '%s' in", SvPVX (name_sv)));
161 else
162 res_pair ("in an unnamed lexical in");
163 }
164
165 --depth;
166 }
167 }
168
169 if (CvCONST (sv) && (SV*)CvXSUBANY (sv).any_ptr == targ)
170 res_pair ("the constant value of");
171
172 if (!CvWEAKOUTSIDE (sv) && (SV*)CvOUTSIDE (sv) == targ)
173 res_pair ("the containing scope for");
174
175 if (sv == targ && CvANON (sv))
176 if (CvSTART (sv)
177 && CvSTART (sv)->op_type == OP_NEXTSTATE
178 && CopLINE ((COP *)CvSTART (sv)))
179 res_text (form ("the closure created at %s:%d",
180 CopFILE ((COP *)CvSTART (sv)) ? CopFILE ((COP *)CvSTART (sv)) : "<unknown>",
181 CopLINE ((COP *)CvSTART (sv))));
182 else
183 res_text (form ("the closure created somewhere in file %s (PLEASE REPORT!)",
184 CvFILE (sv) ? CvFILE (sv) : "<unknown>"));
185 }
186
187 break;
188
189 case SVt_PVGV:
190 if (GvGP (sv))
191 {
192 if (GvSV (sv) == (SV *)targ) res_gv ('$');
193 if (GvAV (sv) == (AV *)targ) res_gv ('@');
194 if (GvHV (sv) == (HV *)targ) res_gv ('%');
195 if (GvCV (sv) == (CV *)targ) res_gv ('&');
196 }
197
198 break;
199 }
200
201 if (rmagical)
202 SvRMAGICAL_on (sv);
203 }
204 }
205
206 if (targ == (SV*)PL_main_cv)
207 res_text ("the main body of the program");
208
209 EXTEND (SP, 2);
210 PUSHs (sv_2mortal (newRV_noinc ((SV *)about)));
211 PUSHs (sv_2mortal (newRV_noinc ((SV *)excl)));
212 }
213
214 SV *
215 ptr2ref (UV ptr)
216 CODE:
217 RETVAL = newRV_inc (INT2PTR (SV *, ptr));
218 OUTPUT:
219 RETVAL
220
221 UV
222 ref2ptr (SV *rv)
223 CODE:
224 RETVAL = PTR2UV (SvRV (rv));
225 OUTPUT:
226 RETVAL
227
228 U32
229 _refcnt (SV *rv)
230 CODE:
231 RETVAL = SvREFCNT (SvRV (rv));
232 OUTPUT:
233 RETVAL