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