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 IV 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 (id && SvOK(id) && SvIOK(id)) ? SvIV(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  SvIOK_on(val);
  62  SvIsUV_on(val);
  63  if (!hv_store(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), val, 0))
  64   SvREFCNT_dec(val);
  65 }
  66
  67 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV ** const name) {
  68 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  69  char buf[32];
  70  SV **val;
  71
  72  if (indirect_linestr != SvPVX_const(PL_parser->linestr))
  73   return NULL;
  74
  75  val = hv_fetch(indirect_map, buf, sprintf(buf, "%u", PTR2UV(o)), 0);
  76  if (!val) {
  77   *name = NULL;
  78   return NULL;
  79  }
  80
  81  *name = *val;
  82  return INT2PTR(const char *, SvUVX(*val));
  83 }
  84
  85 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
  86 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
  87  STRLEN len;
  88  const char *p = NULL, *r = SvPV_const(sv, len);
  89
  90  if (!len)
  91   return s;
  92
  93  p = strstr(s, r);
  94  while (p) {
  95   p += len;
  96   if (!isALNUM(*p))
  97    break;
  98   p = strstr(p + 1, r);
  99  }
 100
 101  return p;
 102 }
 103
 104 /* ... ck_const ............................................................ */
 105
 106 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 107
 108 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 109  if (indirect_hint()) {
 110   SV *sv = cSVOPo_sv;
 111   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 112    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 113  }
 114
 115  return CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 116 }
 117
 118 /* ... ck_rv2sv ............................................................ */
 119
 120 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 121
 122 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 123  if (indirect_hint()) {
 124   OP *op = cUNOPo->op_first;
 125   SV *name = cSVOPx_sv(op);
 126   if (SvPOK(name) && (SvTYPE(name) >= SVt_PV)) {
 127    SV *sv = sv_2mortal(newSVpvn("$", 1));
 128    sv_catsv(sv, name);
 129    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 130   }
 131  }
 132
 133  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 134 }
 135
 136 /* ... ck_padany ........................................................... */
 137
 138 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 139
 140 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 141  if (indirect_hint()) {
 142   SV *sv;
 143   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 144
 145   while (s < t && isSPACE(*s)) ++s;
 146   while (t > s && isSPACE(*t)) --t;
 147   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 148
 149   indirect_map_store(o, s, sv);
 150  }
 151
 152  return CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 153 }
 154
 155 /* ... ck_method ........................................................... */
 156
 157 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 158
 159 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 160  if (indirect_hint()) {
 161   OP *op = cUNOPo->op_first;
 162   SV *sv;
 163   const char *s = indirect_map_fetch(op, &sv);
 164   if (!s) {
 165    sv = cSVOPx_sv(op);
 166    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 167     goto done;
 168    sv = sv_mortalcopy(sv);
 169    s  = indirect_find(sv, PL_parser->oldbufptr);
 170   }
 171   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 172   /* o may now be a method_named */
 173   indirect_map_store(o, s, sv);
 174   return o;
 175  }
 176
 177 done:
 178  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 179 }
 180
 181 /* ... ck_entersub ......................................................... */
 182
 183 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
 184
 185 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 186
 187 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 188  LISTOP *op;
 189  OP *om, *oo;
 190  IV hint = indirect_hint();
 191
 192  if (hint) {
 193   const char *pm, *po;
 194   SV *svm, *svo;
 195   oo = o;
 196   do {
 197    op = (LISTOP *) oo;
 198    if (!op->op_flags & OPf_KIDS)
 199     goto done;
 200    oo = op->op_first;
 201   } while (oo->op_type != OP_PUSHMARK);
 202   oo = oo->op_sibling;
 203   om = op->op_last;
 204   if (om->op_type == OP_METHOD)
 205    om = cUNOPx(om)->op_first;
 206   else if (om->op_type != OP_METHOD_NAMED)
 207    goto done;
 208   pm = indirect_map_fetch(om, &svm);
 209   po = indirect_map_fetch(oo, &svo);
 210   if (pm && po && pm < po) {
 211    const char *psvm = SvPV_nolen_const(svm), *psvo = SvPV_nolen_const(svo);
 212    if (hint == 2)
 213     croak(indirect_msg, psvm, psvo);
 214    else
 215     warn(indirect_msg, psvm, psvo);
 216   }
 217  }
 218
 219 done:
 220  return CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 221 }
 222
 223 STATIC U32 indirect_initialized = 0;
 224
 225 /* --- XS ------------------------------------------------------------------ */
 226
 227 MODULE = indirect      PACKAGE = indirect
 228
 229 PROTOTYPES: DISABLE
 230
 231 BOOT:
 232 {
 233  if (!indirect_initialized++) {
 234   PERL_HASH(indirect_hash, "indirect", 8);
 235   indirect_map = newHV();
 236   indirect_old_ck_const    = PL_check[OP_CONST];
 237   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 238   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 239   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 240   indirect_old_ck_padany   = PL_check[OP_PADANY];
 241   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 242   indirect_old_ck_method   = PL_check[OP_METHOD];
 243   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 244   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 245   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 246  }
 247 }