indirect.xs

   1 /* This file is part of the indirect Perl module.
   2  * See http://search.cpan.org/dist/indirect/ */
   3
   4 #define PERL_NO_GET_CONTEXT
   5 #include "EXTERN.h"
   6 #include "perl.h"
   7 #include "XSUB.h"
   8
   9 #ifndef SvPV_const
  10 # define SvPV_const SvPV
  11 #endif
  12
  13 #ifndef SvPV_nolen_const
  14 # define SvPV_nolen_const SvPV_nolen
  15 #endif
  16
  17 #ifndef SvPVX_const
  18 # define SvPVX_const SvPVX
  19 #endif
  20
  21 /* ... Hints ............................................................... */
  22
  23 STATIC U32 indirect_hash = 0;
  24
  25 STATIC UV indirect_hint(pTHX) {
  26 #define indirect_hint() indirect_hint(aTHX)
  27  SV *id = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
  28                                          NULL,
  29                                          "indirect", 8,
  30                                          0,
  31                                          indirect_hash);
  32  return SvOK(id) ? SvUV(id) : 0;
  33 }
  34
  35 /* ... op -> source position ............................................... */
  36
  37 STATIC HV *indirect_map = NULL;
  38 STATIC const char *indirect_linestr = NULL;
  39
  40 STATIC void indirect_map_store(pTHX_ const OP *o, const char *src, SV *sv) {
  41 #define indirect_map_store(O, S, N) indirect_map_store(aTHX_ (O), (S), (N))
  42  char buf[32];
  43  const char *pl_linestr;
  44  SV *val;
  45
  46  /* When lex_inwhat is set, we're in a quotelike environment (qq, qr, but not q)
  47   * In this case the linestr has temporarly changed, but the old buffer should
  48   * still be alive somewhere. */
  49
  50  if (!PL_parser->lex_inwhat) {
  51   pl_linestr = SvPVX_const(PL_parser->linestr);
  52   if (indirect_linestr != pl_linestr) {
  53    hv_clear(indirect_map);
  54    indirect_linestr = pl_linestr;
  55   }
  56  }
  57
  58  val = newSVsv(sv);
  59  SvUPGRADE(val, SVt_PVIV);
  60  SvUVX(val) = PTR2UV(src);
  61  if (!hv_store(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), val, 0))
  62   SvREFCNT_dec(val);
  63 }
  64
  65 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV ** const name) {
  66 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  67  char buf[32];
  68  SV **val;
  69
  70  if (indirect_linestr != SvPVX_const(PL_parser->linestr))
  71   return NULL;
  72
  73  val = hv_fetch(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), 0);
  74  if (!val) {
  75   *name = NULL;
  76   return NULL;
  77  }
  78
  79  *name = *val;
  80  return INT2PTR(const char *, SvUVX(*val));
  81 }
  82
  83 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
  84 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
  85  STRLEN len;
  86  const char *p = NULL, *r = SvPV_const(sv, len);
  87
  88  if (!len)
  89   return s;
  90
  91  p = strstr(s, r);
  92  while (p) {
  93   p += len;
  94   if (!isALNUM(*p))
  95    break;
  96   p = strstr(p + 1, r);
  97  }
  98
  99  return p;
 100 }
 101
 102 /* ... ck_const ............................................................ */
 103
 104 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 105
 106 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 107  if (indirect_hint()) {
 108   SV *sv = cSVOPo_sv;
 109   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 110    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 111  }
 112
 113  return CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 114 }
 115
 116 /* ... ck_rv2sv ............................................................ */
 117
 118 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 119
 120 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 121  if (indirect_hint()) {
 122   OP *op = cUNOPo->op_first;
 123   SV *name = cSVOPx_sv(op);
 124   if (SvPOK(name) && (SvTYPE(name) >= SVt_PV)) {
 125    SV *sv = sv_2mortal(newSVpvn("$", 1));
 126    sv_catsv(sv, name);
 127    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 128   }
 129  }
 130
 131  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 132 }
 133
 134 /* ... ck_padany ........................................................... */
 135
 136 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 137
 138 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 139  if (indirect_hint()) {
 140   SV *sv;
 141   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 142
 143   while (s < t && isSPACE(*s)) ++s;
 144   while (t > s && isSPACE(*t)) --t;
 145   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 146
 147   indirect_map_store(o, s, sv);
 148  }
 149
 150  return CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 151 }
 152
 153 /* ... ck_method ........................................................... */
 154
 155 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 156
 157 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 158  if (indirect_hint()) {
 159   OP *op = cUNOPo->op_first;
 160   SV *sv;
 161   const char *s = indirect_map_fetch(op, &sv);
 162   if (!s) {
 163    sv = cSVOPx_sv(op);
 164    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 165     goto done;
 166    sv = sv_mortalcopy(sv);
 167    s  = indirect_find(sv, PL_parser->oldbufptr);
 168   }
 169   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 170   /* o may now be a method_named */
 171   indirect_map_store(o, s, sv);
 172   return o;
 173  }
 174
 175 done:
 176  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 177 }
 178
 179 /* ... ck_entersub ......................................................... */
 180
 181 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
 182
 183 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 184
 185 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 186  LISTOP *op;
 187  OP *om, *oo;
 188  UV hint = indirect_hint();
 189
 190  if (hint) {
 191   const char *pm, *po;
 192   SV *svm, *svo;
 193   op = (LISTOP *) o;
 194   while (op->op_type != OP_PUSHMARK)
 195    op = (LISTOP *) op->op_first;
 196   oo = op->op_sibling;
 197   om = oo;
 198   while (om->op_sibling)
 199    om = om->op_sibling;
 200   if (om->op_type == OP_METHOD)
 201    om = cUNOPx(om)->op_first;
 202   else if (om->op_type != OP_METHOD_NAMED)
 203    goto done;
 204   pm = indirect_map_fetch(om, &svm);
 205   po = indirect_map_fetch(oo, &svo);
 206   if (pm && po && pm < po)
 207    ((hint == 2) ? croak : warn)(indirect_msg, SvPV_nolen_const(svm),
 208                                               SvPV_nolen_const(svo));
 209  }
 210
 211 done:
 212  return CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 213 }
 214
 215 STATIC U32 indirect_initialized = 0;
 216
 217 /* --- XS ------------------------------------------------------------------ */
 218
 219 MODULE = indirect      PACKAGE = indirect
 220
 221 PROTOTYPES: DISABLE
 222
 223 BOOT:
 224 {
 225  if (!indirect_initialized++) {
 226   PERL_HASH(indirect_hash, "indirect", 8);
 227   indirect_map = newHV();
 228   indirect_old_ck_const    = PL_check[OP_CONST];
 229   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 230   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 231   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 232   indirect_old_ck_padany   = PL_check[OP_PADANY];
 233   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 234   indirect_old_ck_method   = PL_check[OP_METHOD];
 235   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 236   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 237   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 238  }
 239 }