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 #ifndef sv_catpvn_nomg
  22 # define sv_catpvn_nomg sv_catpvn
  23 #endif
  24
  25 /* ... Hints ............................................................... */
  26
  27 STATIC U32 indirect_hash = 0;
  28
  29 STATIC IV indirect_hint(pTHX) {
  30 #define indirect_hint() indirect_hint(aTHX)
  31  SV *id = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
  32                                          NULL,
  33                                          "indirect", 8,
  34                                          0,
  35                                          indirect_hash);
  36  return (id && SvOK(id) && SvIOK(id)) ? SvIV(id) : 0;
  37 }
  38
  39 /* ... op -> source position ............................................... */
  40
  41 STATIC HV *indirect_map = NULL;
  42 STATIC const char *indirect_linestr = NULL;
  43
  44 #define OP2STR(O) (sprintf(buf, "%u", PTR2UV(o)))
  45
  46 STATIC void indirect_map_store(pTHX_ const OP *o, const char *src, SV *sv) {
  47 #define indirect_map_store(O, S, N) indirect_map_store(aTHX_ (O), (S), (N))
  48  char buf[32];
  49  const char *pl_linestr;
  50  SV *val;
  51
  52  /* When lex_inwhat is set, we're in a quotelike environment (qq, qr, but not q)
  53   * In this case the linestr has temporarly changed, but the old buffer should
  54   * still be alive somewhere. */
  55
  56  if (!PL_parser->lex_inwhat) {
  57   pl_linestr = SvPVX_const(PL_parser->linestr);
  58   if (indirect_linestr != pl_linestr) {
  59    hv_clear(indirect_map);
  60    indirect_linestr = pl_linestr;
  61   }
  62  }
  63
  64  val = newSVsv(sv);
  65  SvUPGRADE(val, SVt_PVIV);
  66  SvUVX(val) = PTR2UV(src);
  67  SvIOK_on(val);
  68  SvIsUV_on(val);
  69  if (!hv_store(indirect_map, buf, OP2STR(o), val, 0)) SvREFCNT_dec(val);
  70 }
  71
  72 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV ** const name) {
  73 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  74  char buf[32];
  75  SV **val;
  76
  77  if (indirect_linestr != SvPVX_const(PL_parser->linestr))
  78   return NULL;
  79
  80  val = hv_fetch(indirect_map, buf, OP2STR(o), 0);
  81  if (!val) {
  82   *name = NULL;
  83   return NULL;
  84  }
  85
  86  *name = *val;
  87  return INT2PTR(const char *, SvUVX(*val));
  88 }
  89
  90 STATIC void indirect_map_delete(pTHX_ const OP *o) {
  91 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
  92  char buf[32];
  93
  94  hv_delete(indirect_map, buf, OP2STR(o), G_DISCARD);
  95 }
  96
  97 STATIC void indirect_map_clean(pTHX_ const OP *o) {
  98 #define indirect_map_clean(O) indirect_map_clean(aTHX_ (O))
  99  if (o->op_flags & OPf_KIDS) {
 100   const OP *kid = cUNOPo->op_first;
 101   for (; kid; kid = kid->op_sibling) {
 102    indirect_map_delete(kid);
 103    indirect_map_clean(kid);
 104   }
 105  } else {
 106   indirect_map_delete(o);
 107  }
 108 }
 109
 110 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
 111 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
 112  STRLEN len;
 113  const char *p = NULL, *r = SvPV_const(sv, len);
 114
 115  p = strstr(s, r);
 116  while (p) {
 117   p += len;
 118   if (!isALNUM(*p))
 119    break;
 120   p = strstr(p + 1, r);
 121  }
 122
 123  return p;
 124 }
 125
 126 /* ... ck_const ............................................................ */
 127
 128 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 129
 130 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 131  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 132
 133  if (indirect_hint()) {
 134   SV *sv = cSVOPo_sv;
 135   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 136    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 137  }
 138
 139  return o;
 140 }
 141
 142 /* ... ck_rv2sv ............................................................ */
 143
 144 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 145
 146 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 147  if (indirect_hint()) {
 148   OP *op = cUNOPo->op_first;
 149   const char *name = NULL;
 150   STRLEN len;
 151   switch (op->op_type) {
 152    case OP_GV:
 153    case OP_GVSV: {
 154     GV *gv = cGVOPx_gv(op);
 155     name = GvNAME(gv);
 156     len  = GvNAMELEN(gv);
 157     break;
 158    }
 159    default: {
 160     SV *sv = cSVOPx_sv(op);
 161     if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 162      name = SvPV_const(sv, len);
 163     break;
 164    }
 165   }
 166   if (name) {
 167    SV *sv = sv_2mortal(newSVpvn("$", 1));
 168    sv_catpvn_nomg(sv, name, len);
 169    const char *s;
 170    s = indirect_find(sv, PL_parser->oldbufptr);
 171    if (!s) { /* If it failed, retry without the current stash */
 172     const char *stash = HvNAME_get(PL_curstash);
 173     STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 174     if ((len < stashlen + 2) || name != strstr(name, stash)) {
 175      /* Failed again ? Try to remove main */
 176      stash = "main";
 177      stashlen = 4;
 178      if ((len < stashlen + 2) || name != strstr(name, stash))
 179       goto done;
 180     }
 181     sv_setpvn(sv, "$", 1);
 182     if (name[stashlen] != ':' || name[stashlen+1] != ':')
 183      goto done;
 184     stashlen += 2;
 185     sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 186     s = indirect_find(sv, PL_parser->oldbufptr);
 187     if (!s)
 188      goto done;
 189    }
 190    o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 191    indirect_map_store(o, s, sv);
 192    return o;
 193   }
 194  }
 195
 196 done:
 197  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 198 }
 199
 200 /* ... ck_padany ........................................................... */
 201
 202 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 203
 204 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 205  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 206
 207  if (indirect_hint()) {
 208   SV *sv;
 209   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 210
 211   while (s < t && isSPACE(*s)) ++s;
 212   while (t > s && isSPACE(*t)) --t;
 213   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 214
 215   indirect_map_store(o, s, sv);
 216  }
 217
 218  return o;
 219 }
 220
 221 /* ... ck_method ........................................................... */
 222
 223 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 224
 225 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 226  if (indirect_hint()) {
 227   OP *op = cUNOPo->op_first;
 228   SV *sv;
 229   const char *s = indirect_map_fetch(op, &sv);
 230   if (!s) {
 231    sv = cSVOPx_sv(op);
 232    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 233     goto done;
 234    sv = sv_mortalcopy(sv);
 235    s  = indirect_find(sv, PL_parser->oldbufptr);
 236   }
 237   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 238   /* o may now be a method_named */
 239   indirect_map_store(o, s, sv);
 240   return o;
 241  }
 242
 243 done:
 244  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 245 }
 246
 247 /* ... ck_entersub ......................................................... */
 248
 249 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
 250
 251 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 252
 253 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 254  LISTOP *op;
 255  OP *om, *oo;
 256  IV hint = indirect_hint();
 257
 258  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 259
 260  if (hint) {
 261   const char *pm, *po;
 262   SV *svm, *svo;
 263   oo = o;
 264   do {
 265    op = (LISTOP *) oo;
 266    if (!op->op_flags & OPf_KIDS)
 267     goto done;
 268    oo = op->op_first;
 269   } while (oo->op_type != OP_PUSHMARK);
 270   oo = oo->op_sibling;
 271   om = op->op_last;
 272   if (om->op_type == OP_METHOD)
 273    om = cUNOPx(om)->op_first;
 274   else if (om->op_type != OP_METHOD_NAMED)
 275    goto done;
 276   pm = indirect_map_fetch(om, &svm);
 277   po = indirect_map_fetch(oo, &svo);
 278   if (pm && po && pm < po) {
 279    const char *psvm = SvPV_nolen_const(svm), *psvo = SvPV_nolen_const(svo);
 280    if (hint == 2)
 281     croak(indirect_msg, psvm, psvo);
 282    else
 283     warn(indirect_msg, psvm, psvo);
 284   }
 285 done:
 286   indirect_map_clean(o);
 287  }
 288
 289  return o;
 290 }
 291
 292 STATIC U32 indirect_initialized = 0;
 293
 294 /* --- XS ------------------------------------------------------------------ */
 295
 296 MODULE = indirect      PACKAGE = indirect
 297
 298 PROTOTYPES: DISABLE
 299
 300 BOOT:
 301 {
 302  if (!indirect_initialized++) {
 303   PERL_HASH(indirect_hash, "indirect", 8);
 304   indirect_map = newHV();
 305   indirect_old_ck_const    = PL_check[OP_CONST];
 306   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 307   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 308   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 309   indirect_old_ck_padany   = PL_check[OP_PADANY];
 310   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 311   indirect_old_ck_method   = PL_check[OP_METHOD];
 312   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 313   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 314   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 315  }
 316 }