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))
  70   SvREFCNT_dec(val);
  71 }
  72
  73 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV ** const name) {
  74 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  75  char buf[32];
  76  SV **val;
  77
  78  if (indirect_linestr != SvPVX_const(PL_parser->linestr))
  79   return NULL;
  80
  81  val = hv_fetch(indirect_map, buf, OP2STR(o), 0);
  82  if (!val) {
  83   *name = NULL;
  84   return NULL;
  85  }
  86
  87  *name = *val;
  88  return INT2PTR(const char *, SvUVX(*val));
  89 }
  90
  91 STATIC void indirect_map_delete(pTHX_ const OP *o) {
  92 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
  93  char buf[32];
  94
  95  hv_delete(indirect_map, buf, OP2STR(o), G_DISCARD);
  96 }
  97
  98 STATIC void indirect_map_clean(pTHX_ const OP *o) {
  99 #define indirect_map_clean(O) indirect_map_clean(aTHX_ (O))
 100  if (o->op_flags & OPf_KIDS) {
 101   const OP *kid = cUNOPo->op_first;
 102   for (; kid; kid = kid->op_sibling) {
 103    indirect_map_delete(kid);
 104    indirect_map_clean(kid);
 105   }
 106  } else {
 107   indirect_map_delete(o);
 108  }
 109 }
 110
 111 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
 112 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
 113  STRLEN len;
 114  const char *p = NULL, *r = SvPV_const(sv, len);
 115
 116  if (!len)
 117   return s;
 118
 119  p = strstr(s, r);
 120  while (p) {
 121   p += len;
 122   if (!isALNUM(*p))
 123    break;
 124   p = strstr(p + 1, r);
 125  }
 126
 127  return p;
 128 }
 129
 130 /* ... ck_const ............................................................ */
 131
 132 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 133
 134 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 135  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 136
 137  if (indirect_hint()) {
 138   SV *sv = cSVOPo_sv;
 139   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 140    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 141  }
 142
 143  return o;
 144 }
 145
 146 /* ... ck_rv2sv ............................................................ */
 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   const char *name = NULL;
 154   STRLEN len;
 155   switch (op->op_type) {
 156    case OP_GV:
 157    case OP_GVSV: {
 158     GV *gv = cGVOPx_gv(op);
 159     name = GvNAME(gv);
 160     len  = GvNAMELEN(gv);
 161     break;
 162    }
 163    default: {
 164     SV *sv = cSVOPx_sv(op);
 165     if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 166      name = SvPV_const(sv, len);
 167     break;
 168    }
 169   }
 170   if (name) {
 171    SV *sv = sv_2mortal(newSVpvn("$", 1));
 172    sv_catpvn_nomg(sv, name, len);
 173    const char *s;
 174    s = indirect_find(sv, PL_parser->oldbufptr);
 175    if (!s) { /* If it failed, retry without the current stash */
 176     const char *stash = HvNAME_get(PL_curstash);
 177     STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 178     if ((len < stashlen + 2) || name != strstr(name, stash)) {
 179      /* Failed again ? Try to remove main */
 180      stash = "main";
 181      stashlen = 4;
 182      if ((len < stashlen + 2) || name != strstr(name, stash))
 183       goto done;
 184     }
 185     sv_setpvn(sv, "$", 1);
 186     if (name[stashlen] != ':' || name[stashlen+1] != ':')
 187      goto done;
 188     stashlen += 2;
 189     sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 190     s = indirect_find(sv, PL_parser->oldbufptr);
 191     if (!s)
 192      goto done;
 193    }
 194    o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 195    indirect_map_store(o, s, sv);
 196    return o;
 197   }
 198  }
 199
 200 done:
 201  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 202 }
 203
 204 /* ... ck_padany ........................................................... */
 205
 206 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 207
 208 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 209  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 210
 211  if (indirect_hint()) {
 212   SV *sv;
 213   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 214
 215   while (s < t && isSPACE(*s)) ++s;
 216   while (t > s && isSPACE(*t)) --t;
 217   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 218
 219   indirect_map_store(o, s, sv);
 220  }
 221
 222  return o;
 223 }
 224
 225 /* ... ck_method ........................................................... */
 226
 227 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 228
 229 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 230  if (indirect_hint()) {
 231   OP *op = cUNOPo->op_first;
 232   SV *sv;
 233   const char *s = indirect_map_fetch(op, &sv);
 234   if (!s) {
 235    sv = cSVOPx_sv(op);
 236    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 237     goto done;
 238    sv = sv_mortalcopy(sv);
 239    s  = indirect_find(sv, PL_parser->oldbufptr);
 240   }
 241   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 242   /* o may now be a method_named */
 243   indirect_map_store(o, s, sv);
 244   return o;
 245  }
 246
 247 done:
 248  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 249 }
 250
 251 /* ... ck_entersub ......................................................... */
 252
 253 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
 254
 255 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 256
 257 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 258  LISTOP *op;
 259  OP *om, *oo;
 260  IV hint = indirect_hint();
 261
 262  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 263
 264  if (hint) {
 265   const char *pm, *po;
 266   SV *svm, *svo;
 267   oo = o;
 268   do {
 269    op = (LISTOP *) oo;
 270    if (!op->op_flags & OPf_KIDS)
 271     goto done;
 272    oo = op->op_first;
 273   } while (oo->op_type != OP_PUSHMARK);
 274   oo = oo->op_sibling;
 275   om = op->op_last;
 276   if (om->op_type == OP_METHOD)
 277    om = cUNOPx(om)->op_first;
 278   else if (om->op_type != OP_METHOD_NAMED)
 279    goto done;
 280   pm = indirect_map_fetch(om, &svm);
 281   po = indirect_map_fetch(oo, &svo);
 282   if (pm && po && pm < po) {
 283    const char *psvm = SvPV_nolen_const(svm), *psvo = SvPV_nolen_const(svo);
 284    if (hint == 2)
 285     croak(indirect_msg, psvm, psvo);
 286    else
 287     warn(indirect_msg, psvm, psvo);
 288   }
 289 done:
 290   indirect_map_clean(o);
 291  }
 292
 293  return o;
 294 }
 295
 296 STATIC U32 indirect_initialized = 0;
 297
 298 /* --- XS ------------------------------------------------------------------ */
 299
 300 MODULE = indirect      PACKAGE = indirect
 301
 302 PROTOTYPES: DISABLE
 303
 304 BOOT:
 305 {
 306  if (!indirect_initialized++) {
 307   PERL_HASH(indirect_hash, "indirect", 8);
 308   indirect_map = newHV();
 309   indirect_old_ck_const    = PL_check[OP_CONST];
 310   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 311   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 312   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 313   indirect_old_ck_padany   = PL_check[OP_PADANY];
 314   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 315   indirect_old_ck_method   = PL_check[OP_METHOD];
 316   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 317   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 318   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 319  }
 320 }