indirect.xs

   1 #define PERL_NO_GET_CONTEXT
   2 #include "EXTERN.h"
   3 #include "perl.h"
   4 #include "XSUB.h"
   5
   6 #ifndef SvPVX_const
   7 # define SvPVX_const SvPVX
   8 #endif
   9
  10 STATIC U32 indirect_initialized = 0;
  11 STATIC U32 indirect_hash = 0;
  12
  13 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
  14
  15 STATIC HV *indirect_map = NULL;
  16 STATIC const char *indirect_linestr = NULL;
  17
  18 STATIC UV indirect_hint(pTHX) {
  19 #define indirect_hint() indirect_hint(aTHX)
  20  SV *id = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
  21                                          NULL,
  22                                          "indirect", 8,
  23                                          0,
  24                                          indirect_hash);
  25  return SvOK(id) ? SvUV(id) : 0;
  26 }
  27
  28 STATIC void indirect_map_store(pTHX_ const OP *o, const char *src, SV *sv) {
  29 #define indirect_map_store(O, S, N) indirect_map_store(aTHX_ (O), (S), (N))
  30  char buf[32];
  31  const char *pl_linestr;
  32  SV *val;
  33
  34  /* When lex_inwhat is set, we're in a quotelike environment (qq, qr, but not q)
  35   * In this case the linestr has temporarly changed, but the old buffer should
  36   * still be alive somewhere. */
  37
  38  if (!PL_parser->lex_inwhat) {
  39   pl_linestr = SvPVX_const(PL_parser->linestr);
  40   if (indirect_linestr != pl_linestr) {
  41    hv_clear(indirect_map);
  42    indirect_linestr = pl_linestr;
  43   }
  44  }
  45
  46  val = newSVsv(sv);
  47  SvUPGRADE(val, SVt_PVIV);
  48  SvUVX(val) = PTR2UV(src);
  49  if (!hv_store(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), val, 0))
  50   SvREFCNT_dec(val);
  51 }
  52
  53 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV **name) {
  54 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  55  char buf[32];
  56  SV **val;
  57
  58  if (indirect_linestr != SvPVX(PL_parser->linestr))
  59   return NULL;
  60
  61  val = hv_fetch(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), 0);
  62  if (!val) {
  63   *name = NULL;
  64   return NULL;
  65  }
  66
  67  *name = *val;
  68  return INT2PTR(const char *, SvUVX(*val));
  69 }
  70
  71 STATIC UV indirect_intuit(const char *meth, const char *obj) {
  72  const char *s;
  73  int indirect = 0, quotelike = 0;
  74
  75  for (s = meth; s < obj; ++s) {
  76   switch (*s) {
  77    case ',':
  78    case '(':
  79    case '=':
  80    case '\'':
  81    case '"':
  82    case '`':
  83     return 0;
  84    case '-':
  85     indirect = 1;
  86     break;
  87    case '>':
  88     if (indirect)
  89      return 0;
  90     break;
  91    case 'q':
  92     indirect = 0;
  93     if (quotelike == 1)
  94      quotelike = 2;
  95     break;
  96    case 'w':
  97    case 'r':
  98    case 'x':
  99     indirect = 0;
 100     if (quotelike != 2)
 101      quotelike = 0;
 102     break;
 103    default:
 104     indirect = 0;
 105     if (isSPACE(*s))
 106      quotelike = 1;
 107     else if (quotelike == 2 && !isALNUM(*s))
 108      return 0;
 109     else
 110      quotelike = 0;
 111   }
 112  }
 113
 114  return 1;
 115 }
 116
 117 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
 118 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
 119  STRLEN len;
 120  const char *p = NULL, *r = SvPV_const(sv, len);
 121
 122  if (!len)
 123   return s;
 124
 125  p = strstr(s, r);
 126  while (p) {
 127   p += len;
 128   if (!isALNUM(*p))
 129    break;
 130   p = strstr(p + 1, r);
 131  }
 132
 133  return p;
 134 }
 135
 136 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 137
 138 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 139  if (indirect_hint()) {
 140   SV *sv = cSVOPo_sv;
 141   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 142    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 143  }
 144
 145  return CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 146 }
 147
 148 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 149
 150 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 151  if (indirect_hint()) {
 152   OP *op = cUNOPo->op_first;
 153   SV *name = cSVOPx_sv(op);
 154   if (SvPOK(name) && (SvTYPE(name) >= SVt_PV)) {
 155    SV *sv = sv_2mortal(newSVpvn("$", 1));
 156    sv_catsv(sv, name);
 157    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 158   }
 159  }
 160
 161  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 162 }
 163
 164 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 165
 166 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 167  if (indirect_hint()) {
 168   SV *sv;
 169   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 170
 171   while (s < t && isSPACE(*s)) ++s;
 172   while (t > s && isSPACE(*t)) --t;
 173   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 174
 175   indirect_map_store(o, s, sv);
 176  }
 177
 178  return CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 179 }
 180
 181 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 182
 183 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 184  if (indirect_hint()) {
 185   OP *op = cUNOPo->op_first;
 186   SV *sv;
 187   const char *s = indirect_map_fetch(op, &sv);
 188   if (!s) {
 189    sv = cSVOPx_sv(op);
 190    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 191     goto done;
 192    sv = sv_mortalcopy(sv);
 193    s  = indirect_find(sv, PL_parser->oldbufptr);
 194   }
 195   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 196   /* o may now be a method_named */
 197   indirect_map_store(o, s, sv);
 198   return o;
 199  }
 200
 201 done:
 202  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 203 }
 204
 205 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 206
 207 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 208  LISTOP *op;
 209  OP *om, *oo;
 210  UV hint = indirect_hint();
 211
 212  if (hint) {
 213   const char *pm, *po;
 214   SV *svm, *svo;
 215   op = (LISTOP *) o;
 216   while (op->op_type != OP_PUSHMARK)
 217    op = (LISTOP *) op->op_first;
 218   oo = op->op_sibling;
 219   om = oo;
 220   while (om->op_sibling)
 221    om = om->op_sibling;
 222   if (om->op_type == OP_METHOD)
 223    om = cUNOPx(om)->op_first;
 224   pm = indirect_map_fetch(om, &svm);
 225   po = indirect_map_fetch(oo, &svo);
 226   if (pm && po && pm < po && indirect_intuit(pm, po))
 227    ((hint == 2) ? croak : warn)(indirect_msg, SvPV_nolen(svm), SvPV_nolen(svo));
 228  }
 229
 230  return CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 231 }
 232
 233 MODULE = indirect      PACKAGE = indirect
 234
 235 PROTOTYPES: DISABLE
 236
 237 BOOT:
 238 {
 239  if (!indirect_initialized++) {
 240   PERL_HASH(indirect_hash, "indirect", 8);
 241   indirect_map = newHV();
 242   indirect_old_ck_const    = PL_check[OP_CONST];
 243   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 244   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 245   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 246   indirect_old_ck_padany   = PL_check[OP_PADANY];
 247   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 248   indirect_old_ck_method   = PL_check[OP_METHOD];
 249   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 250   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 251   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 252  }
 253 }