Devel-FindRef/FindRef.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#define PERL_VERSION_ATLEAST(a,b,c)                             \
  (PERL_REVISION > (a)                                          \
   || (PERL_REVISION == (a)                                     \
       && (PERL_VERSION > (b)                                   \
           || (PERL_VERSION == (b) && PERLSUBVERSION >= (c)))))

#if !PERL_VERSION_ATLEAST (5,8,9)
# define SVt_LAST 16
#endif

#define res_pair(text)                                          \
  do {                                                          \
    AV *av = newAV ();                                          \
    av_push (av, newSVpv (text, 0));                            \
    if (rmagical) SvRMAGICAL_on (sv);                           \
    av_push (av, sv_rvweaken (newRV_inc (sv)));                 \
    if (rmagical) SvRMAGICAL_off (sv);                          \
    av_push (about, newRV_noinc ((SV *)av));                    \
  } while (0)

#define res_gv(sigil)                                           \
  do {                                                          \
    AV *av = newAV ();                                          \
    av_push (av, newSVpv (form ("in the global %c%s::%.*s", sigil, \
                                HvNAME (GvSTASH (sv)),          \
                                GvNAMELEN (sv), GvNAME (sv) ? GvNAME (sv) : "<anonymous>"), \
                          0));                                  \
    av_push (about, newRV_noinc ((SV *)av));                    \
  } while (0)

MODULE = Devel::FindRef         PACKAGE = Devel::FindRef                

PROTOTYPES: ENABLE

SV *
ptr2ref (IV ptr)
        CODE:
        RETVAL = newRV_inc (INT2PTR (SV *, ptr));
        OUTPUT:
        RETVAL

void
find_ (SV *target)
        PPCODE:
{
        SV *arena, *targ;
        int rmagical, i;
        AV *about = newAV ();
        AV *excl  = newAV ();

        if (!SvROK (target))
          croak ("find expects a reference to a perl value");

        targ = SvRV (target);

        for (arena = PL_sv_arenaroot; arena; arena = SvANY (arena))
          {
            UV idx = SvREFCNT (arena);

            /* Remember that the zeroth slot is used as the pointer onwards, so don't
               include it. */
            while (--idx > 0)
              {
                SV *sv = &arena [idx];

                if (SvTYPE (sv) >= SVt_LAST)
                  continue;

                /* temporarily disable RMAGICAL, it can easily interfere with us */
                if ((rmagical = SvRMAGICAL (sv)))
                  SvRMAGICAL_off (sv);

                if (SvTYPE (sv) >= SVt_PVMG)
                  {
                    MAGIC *mg = SvMAGIC (sv);
                    while (mg)
                      {
                        if (mg->mg_obj == targ)
                          res_pair (form ("referenced (in mg_obj) by '%c' type magic attached to", mg->mg_type));

                        if ((SV *)mg->mg_ptr == targ && mg->mg_flags & MGf_REFCOUNTED)
                          res_pair (form ("referenced (in mg_ptr) by '%c' type magic attached to", mg->mg_type));

                        mg = mg->mg_moremagic;
                      }
                  }

                if (SvROK (sv))
                  {
                    if (sv != target && SvRV (sv) == targ && !SvWEAKREF (sv))
                      res_pair ("referenced by");
                  }
                else
                  switch (SvTYPE (sv))
                    {
                      case SVt_PVAV:
                        if (AvREAL (sv))
                          for (i = AvFILLp (sv) + 1; i--; )
                            if (AvARRAY (sv)[i] == targ)
                              res_pair (form ("in array element %d of", i));

                        break;

                      case SVt_PVHV:
                        if (hv_iterinit ((HV *)sv))
                          {
                            HE *he;

                            while ((he = hv_iternext ((HV *)sv)))
                              if (HeVAL (he) == targ)
                                res_pair (form ("in the member '%.*s' of", HeKLEN (he), HeKEY (he)));
                          }

                        break;

                      case SVt_PVCV:
                        {
                          int depth = CvDEPTH (sv);

                          /* Anonymous subs have a padlist but zero depth */
                          if (!depth && CvPADLIST (sv))
                            depth = 1;

                          if (depth)
                            {
                              AV *padlist = CvPADLIST (sv);

                              while (depth)
                                {
                                  AV *pad = (AV *)AvARRAY (padlist)[depth];

                                  av_push (excl, newSVuv (PTR2UV (pad))); /* exclude pads themselves from being found */

                                  for (i = AvFILLp (pad) + 1; i--; )
                                    if (AvARRAY (pad)[i] == targ)
                                      {
                                        /* Values from constant functions are stored in the pad without any name */
                                        SV *name_sv = AvARRAY (AvARRAY (padlist)[0])[i];

                                        if (name_sv && SvPOK (name_sv))
                                          res_pair (form ("in the lexical '%s' in", SvPVX (name_sv)));
                                        else
                                          res_pair ("in an unnamed lexical in");
                                      }

                                  --depth;
                                }
                            }

                          if (CvCONST (sv) && (SV*)CvXSUBANY (sv).any_ptr == targ)
                            res_pair ("the constant value of");

                          if (!CvWEAKOUTSIDE (sv) && (SV*)CvOUTSIDE (sv) == targ)
                            res_pair ("the containing scope for");
                        }

                        break;

                      case SVt_PVGV:
                        if (GvGP (sv))
                          {
                            if (GvSV (sv) == (SV *)targ) res_gv ('$');
                            if (GvAV (sv) == (AV *)targ) res_gv ('@');
                            if (GvHV (sv) == (HV *)targ) res_gv ('%');
                            if (GvCV (sv) == (CV *)targ) res_gv ('&');
                          }

                        break;
                    }

                if (rmagical)
                  SvRMAGICAL_on (sv);
              }
          }

        EXTEND (SP, 2);
        PUSHs (sv_2mortal (newRV_noinc ((SV *)about)));
        PUSHs (sv_2mortal (newRV_noinc ((SV *)excl)));
}

Revision:	1.8
Committed:	Sun Apr 27 05:59:06 2008 UTC (16 years ago) by root
Branch:	MAIN
Changes since 1.7:	+19 -7 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5	root	1.4	#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	root	1.6	#define res_pair(text) \
16	root	1.8	do { \
17	root	1.6	AV *av = newAV (); \
18			av_push (av, newSVpv (text, 0)); \
19	root	1.7	if (rmagical) SvRMAGICAL_on (sv); \
20	root	1.6	av_push (av, sv_rvweaken (newRV_inc (sv))); \
21	root	1.7	if (rmagical) SvRMAGICAL_off (sv); \
22	root	1.6	av_push (about, newRV_noinc ((SV *)av)); \
23	root	1.8	} while (0)
24	root	1.1
25	root	1.6	#define res_gv(sigil) \
26	root	1.8	do { \
27	root	1.6	AV *av = newAV (); \
28	root	1.1	av_push (av, newSVpv (form ("in the global %c%s::%.*s", sigil, \
29	root	1.6	HvNAME (GvSTASH (sv)), \
30	root	1.1	GvNAMELEN (sv), GvNAME (sv) ? GvNAME (sv) : "<anonymous>"), \
31	root	1.6	0)); \
32			av_push (about, newRV_noinc ((SV *)av)); \
33	root	1.8	} while (0)
34	root	1.1
35			MODULE = Devel::FindRef PACKAGE = Devel::FindRef
36
37			PROTOTYPES: ENABLE
38
39			SV *
40			ptr2ref (IV ptr)
41			CODE:
42			RETVAL = newRV_inc (INT2PTR (SV *, ptr));
43			OUTPUT:
44			RETVAL
45
46			void
47			find_ (SV *target)
48			PPCODE:
49			{
50			SV arena, targ;
51			int rmagical, i;
52			AV *about = newAV ();
53			AV *excl = newAV ();
54
55			if (!SvROK (target))
56	root	1.3	croak ("find expects a reference to a perl value");
57	root	1.1
58			targ = SvRV (target);
59
60			for (arena = PL_sv_arenaroot; arena; arena = SvANY (arena))
61			{
62			UV idx = SvREFCNT (arena);
63
64			/* Remember that the zeroth slot is used as the pointer onwards, so don't
65			include it. */
66			while (--idx > 0)
67			{
68			SV *sv = &arena [idx];
69	root	1.2
70			if (SvTYPE (sv) >= SVt_LAST)
71			continue;
72
73			/* temporarily disable RMAGICAL, it can easily interfere with us */
74	root	1.1	if ((rmagical = SvRMAGICAL (sv)))
75			SvRMAGICAL_off (sv);
76
77	root	1.2	if (SvTYPE (sv) >= SVt_PVMG)
78			{
79			MAGIC *mg = SvMAGIC (sv);
80			while (mg)
81			{
82			if (mg->mg_obj == targ)
83			res_pair (form ("referenced (in mg_obj) by '%c' type magic attached to", mg->mg_type));
84	root	1.6
85	root	1.2	if ((SV *)mg->mg_ptr == targ && mg->mg_flags & MGf_REFCOUNTED)
86			res_pair (form ("referenced (in mg_ptr) by '%c' type magic attached to", mg->mg_type));
87
88			mg = mg->mg_moremagic;
89			}
90			}
91	root	1.1
92	root	1.6	if (SvROK (sv))
93	root	1.1	{
94	root	1.6	if (sv != target && SvRV (sv) == targ && !SvWEAKREF (sv))
95			res_pair ("referenced by");
96			}
97			else
98			switch (SvTYPE (sv))
99			{
100			case SVt_PVAV:
101			if (AvREAL (sv))
102			for (i = AvFILLp (sv) + 1; i--; )
103			if (AvARRAY (sv)[i] == targ)
104			res_pair (form ("in array element %d of", i));
105	root	1.1
106	root	1.6	break;
107	root	1.1
108	root	1.6	case SVt_PVHV:
109			if (hv_iterinit ((HV *)sv))
110	root	1.1	{
111	root	1.6	HE *he;
112	root	1.1
113	root	1.6	while ((he = hv_iternext ((HV *)sv)))
114			if (HeVAL (he) == targ)
115			res_pair (form ("in the member '%.*s' of", HeKLEN (he), HeKEY (he)));
116	root	1.1	}
117	root	1.2
118	root	1.6	break;
119
120			case SVt_PVCV:
121	root	1.2	{
122	root	1.6	int depth = CvDEPTH (sv);
123
124	root	1.8	/* Anonymous subs have a padlist but zero depth */
125			if (!depth && CvPADLIST (sv))
126	root	1.7	depth = 1;
127
128	root	1.6	if (depth)
129			{
130			AV *padlist = CvPADLIST (sv);
131
132			while (depth)
133			{
134			AV pad = (AV )AvARRAY (padlist)[depth];
135
136			av_push (excl, newSVuv (PTR2UV (pad))); /* exclude pads themselves from being found */
137
138	root	1.7	for (i = AvFILLp (pad) + 1; i--; )
139	root	1.6	if (AvARRAY (pad)[i] == targ)
140	root	1.8	{
141			/* Values from constant functions are stored in the pad without any name */
142			SV *name_sv = AvARRAY (AvARRAY (padlist)[0])[i];
143
144			if (name_sv && SvPOK (name_sv))
145			res_pair (form ("in the lexical '%s' in", SvPVX (name_sv)));
146			else
147			res_pair ("in an unnamed lexical in");
148			}
149	root	1.6
150			--depth;
151			}
152			}
153	root	1.7
154	root	1.8	if (CvCONST (sv) && (SV*)CvXSUBANY (sv).any_ptr == targ)
155			res_pair ("the constant value of");
156
157			if (!CvWEAKOUTSIDE (sv) && (SV*)CvOUTSIDE (sv) == targ)
158	root	1.7	res_pair ("the containing scope for");
159	root	1.2	}
160	root	1.6
161			break;
162
163			case SVt_PVGV:
164			if (GvGP (sv))
165			{
166			if (GvSV (sv) == (SV *)targ) res_gv ('$');
167			if (GvAV (sv) == (AV *)targ) res_gv ('@');
168			if (GvHV (sv) == (HV *)targ) res_gv ('%');
169			if (GvCV (sv) == (CV *)targ) res_gv ('&');
170			}
171
172			break;
173			}
174	root	1.1
175			if (rmagical)
176	root	1.5	SvRMAGICAL_on (sv);
177	root	1.1	}
178			}
179
180			EXTEND (SP, 2);
181			PUSHs (sv_2mortal (newRV_noinc ((SV *)about)));
182			PUSHs (sv_2mortal (newRV_noinc ((SV *)excl)));
183			}
184