Parameters.xs

   1 /*
   2 Copyright 2012 Lukas Mai.
   3
   4 This program is free software; you can redistribute it and/or modify it
   5 under the terms of either: the GNU General Public License as published
   6 by the Free Software Foundation; or the Artistic License.
   7
   8 See http://dev.perl.org/licenses/ for more information.
   9  */
  10
  11 #ifdef __GNUC__
  12  #if (__GNUC__ == 4 && __GNUC_MINOR__ >= 6) || __GNUC__ >= 5
  13   #define PRAGMA_GCC_(X) _Pragma(#X)
  14   #define PRAGMA_GCC(X) PRAGMA_GCC_(GCC X)
  15  #endif
  16 #endif
  17
  18 #ifndef PRAGMA_GCC
  19  #define PRAGMA_GCC(X)
  20 #endif
  21
  22 #ifdef DEVEL
  23  #define WARNINGS_RESET PRAGMA_GCC(diagnostic pop)
  24  #define WARNINGS_ENABLEW(X) PRAGMA_GCC(diagnostic warning #X)
  25  #define WARNINGS_ENABLE \
  26         WARNINGS_ENABLEW(-Wall) \
  27         WARNINGS_ENABLEW(-Wextra) \
  28         WARNINGS_ENABLEW(-Wundef) \
  29         WARNINGS_ENABLEW(-Wshadow) \
  30         WARNINGS_ENABLEW(-Wbad-function-cast) \
  31         WARNINGS_ENABLEW(-Wcast-align) \
  32         WARNINGS_ENABLEW(-Wwrite-strings) \
  33         /* WARNINGS_ENABLEW(-Wnested-externs) wtf? */ \
  34         WARNINGS_ENABLEW(-Wstrict-prototypes) \
  35         WARNINGS_ENABLEW(-Wmissing-prototypes) \
  36         WARNINGS_ENABLEW(-Winline) \
  37         WARNINGS_ENABLEW(-Wdisabled-optimization)
  38
  39 #else
  40  #define WARNINGS_RESET
  41  #define WARNINGS_ENABLE
  42 #endif
  43
  44
  45 #define PERL_NO_GET_CONTEXT
  46 #include "EXTERN.h"
  47 #include "perl.h"
  48 #include "XSUB.h"
  49
  50 #include <string.h>
  51
  52 WARNINGS_ENABLE
  53
  54 #define MY_PKG "Function::Parameters"
  55
  56 #define HINTK_KEYWORDS MY_PKG "/keywords"
  57 #define HINTK_NAME_    MY_PKG "/name:"
  58 #define HINTK_SHIFT_   MY_PKG "/shift:"
  59 #define HINTK_ATTRS_   MY_PKG "/attrs:"
  60
  61 #define HAVE_PERL_VERSION(R, V, S) \
  62         (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
  63
  64 typedef struct {
  65         enum {
  66                 FLAG_NAME_OPTIONAL = 1,
  67                 FLAG_NAME_REQUIRED,
  68                 FLAG_NAME_PROHIBITED
  69         } name;
  70         SV *shift;
  71         SV *attrs;
  72 } Spec;
  73
  74 static int (*next_keyword_plugin)(pTHX_ char *, STRLEN, OP **);
  75
  76 static int kw_flags(pTHX_ const char *kw_ptr, STRLEN kw_len, Spec *spec) {
  77         HV *hints;
  78         SV *sv, **psv;
  79         const char *p, *kw_active;
  80         STRLEN kw_active_len;
  81
  82         spec->name = 0;
  83         spec->shift = sv_2mortal(newSVpvs(""));
  84         spec->attrs = sv_2mortal(newSVpvs(""));
  85
  86         if (!(hints = GvHV(PL_hintgv))) {
  87                 return FALSE;
  88         }
  89         if (!(psv = hv_fetchs(hints, HINTK_KEYWORDS, 0))) {
  90                 return FALSE;
  91         }
  92         sv = *psv;
  93         kw_active = SvPV(sv, kw_active_len);
  94         if (kw_active_len <= kw_len) {
  95                 return FALSE;
  96         }
  97         for (
  98                 p = kw_active;
  99                 (p = strchr(p, *kw_ptr)) &&
 100                 p < kw_active + kw_active_len - kw_len;
 101                 p++
 102         ) {
 103                 if (
 104                         (p == kw_active || p[-1] == ' ') &&
 105                         p[kw_len] == ' ' &&
 106                         memcmp(kw_ptr, p, kw_len) == 0
 107                 ) {
 108
 109 #define FETCH_HINTK_INTO(NAME, PTR, LEN, X) do { \
 110         const char *fk_ptr_; \
 111         STRLEN fk_len_; \
 112         SV *fk_sv_; \
 113         fk_sv_ = sv_2mortal(newSVpvs(HINTK_ ## NAME)); \
 114         sv_catpvn(fk_sv_, PTR, LEN); \
 115         fk_ptr_ = SvPV(fk_sv_, fk_len_); \
 116         if (!((X) = hv_fetch(hints, fk_ptr_, fk_len_, 0))) { \
 117                 croak("%s: internal error: $^H{'%.*s'} not set", MY_PKG, (int)fk_len_, fk_ptr_); \
 118         } \
 119 } while (0)
 120
 121                         FETCH_HINTK_INTO(NAME_, kw_ptr, kw_len, psv);
 122                         spec->name = SvIV(*psv);
 123
 124                         FETCH_HINTK_INTO(SHIFT_, kw_ptr, kw_len, psv);
 125                         SvSetSV(spec->shift, *psv);
 126
 127                         FETCH_HINTK_INTO(ATTRS_, kw_ptr, kw_len, psv);
 128                         SvSetSV(spec->attrs, *psv);
 129
 130 #undef FETCH_HINTK_INTO
 131                         return TRUE;
 132                 }
 133         }
 134         return FALSE;
 135 }
 136
 137
 138 #include "toke_on_crack.c.inc"
 139
 140
 141 static int parse_fun(pTHX_ OP **pop, const char *keyword_ptr, STRLEN keyword_len, const Spec *spec) {
 142         SV *gen, *declarator, *params, *sv;
 143         line_t line_start;
 144         int saw_name, saw_colon;
 145         STRLEN len;
 146         char *s;
 147         I32 c;
 148
 149         gen = sv_2mortal(newSVpvs("sub"));
 150         declarator = sv_2mortal(newSVpvn(keyword_ptr, keyword_len));
 151         params = sv_2mortal(newSVpvs(""));
 152
 153         line_start = CopLINE(PL_curcop);
 154         lex_read_space(0);
 155
 156         /* function name */
 157         saw_name = 0;
 158         s = PL_parser->bufptr;
 159         if (spec->name != FLAG_NAME_PROHIBITED && (len = S_scan_word(aTHX_ s, TRUE))) {
 160                 sv_catpvs(gen, " ");
 161                 sv_catpvn(gen, s, len);
 162                 sv_catpvs(declarator, " ");
 163                 sv_catpvn(declarator, s, len);
 164                 lex_read_to(s + len);
 165                 lex_read_space(0);
 166                 saw_name = 1;
 167         } else if (spec->name == FLAG_NAME_REQUIRED) {
 168                 croak("I was expecting a function name, not \"%.*s\"", (int)(PL_parser->bufend - s), s);
 169         } else {
 170                 sv_catpvs(declarator, " (anon)");
 171         }
 172
 173         /* parameters */
 174         c = lex_peek_unichar(0);
 175         if (c == '(') {
 176                 SV *saw_slurpy = NULL;
 177
 178                 lex_read_unichar(0);
 179                 lex_read_space(0);
 180
 181                 for (;;) {
 182                         c = lex_peek_unichar(0);
 183                         if (c == '$' || c == '@' || c == '%') {
 184                                 sv_catpvf(params, "%c", (int)c);
 185                                 lex_read_unichar(0);
 186                                 lex_read_space(0);
 187
 188                                 s = PL_parser->bufptr;
 189                                 if (!(len = S_scan_word(aTHX_ s, FALSE))) {
 190                                         croak("In %"SVf": missing identifier", SVfARG(declarator));
 191                                 }
 192                                 if (saw_slurpy) {
 193                                         croak("In %"SVf": I was expecting \")\" after \"%"SVf"\", not \"%c%.*s\"", SVfARG(declarator), SVfARG(saw_slurpy), (int)c, (int)len, s);
 194                                 }
 195                                 if (c != '$') {
 196                                         saw_slurpy = sv_2mortal(newSVpvf("%c%.*s", (int)c, (int)len, s));
 197                                 }
 198                                 sv_catpvn(params, s, len);
 199                                 sv_catpvs(params, ",");
 200                                 lex_read_to(s + len);
 201                                 lex_read_space(0);
 202
 203                                 c = lex_peek_unichar(0);
 204                                 if (c == ',') {
 205                                         lex_read_unichar(0);
 206                                         lex_read_space(0);
 207                                         continue;
 208                                 }
 209                         }
 210
 211                         if (c == ')') {
 212                                 lex_read_unichar(0);
 213                                 lex_read_space(0);
 214                                 break;
 215                         }
 216
 217                         if (c == -1) {
 218                                 croak("In %"SVf": unexpected EOF in parameter list", SVfARG(declarator));
 219                         }
 220                         croak("In %"SVf": unexpected '%c' in parameter list", SVfARG(declarator), (int)c);
 221                 }
 222         }
 223
 224         /* prototype */
 225         saw_colon = 0;
 226         c = lex_peek_unichar(0);
 227         if (c == ':') {
 228                 lex_read_unichar(0);
 229                 lex_read_space(0);
 230
 231                 c = lex_peek_unichar(0);
 232                 if (c != '(') {
 233                         saw_colon = 1;
 234                 } else {
 235                         sv = sv_2mortal(newSVpvs(""));
 236                         if (!S_scan_str(aTHX_ sv, TRUE, TRUE)) {
 237                                 croak("In %"SVf": malformed prototype", SVfARG(declarator));
 238                         }
 239                         sv_catsv(gen, sv);
 240                         lex_read_space(0);
 241                 }
 242         }
 243
 244         if (saw_name) {
 245                 len = SvCUR(gen);
 246                 s = SvGROW(gen, (len + 1) * 2);
 247                 sv_catpvs(gen, ";");
 248                 sv_catpvn(gen, s, len);
 249         }
 250
 251         /* attributes */
 252         if (SvTRUE(spec->attrs)) {
 253                 sv_catsv(gen, spec->attrs);
 254         }
 255
 256         if (!saw_colon) {
 257                 c = lex_peek_unichar(0);
 258                 if (c == ':') {
 259                         saw_colon = 1;
 260                         lex_read_unichar(0);
 261                         lex_read_space(0);
 262                 }
 263         }
 264         if (saw_colon) {
 265                 for (;;) {
 266                         s = PL_parser->bufptr;
 267                         if (!(len = S_scan_word(aTHX_ s, FALSE))) {
 268                                 break;
 269                         }
 270                         sv_catpvs(gen, ":");
 271                         sv_catpvn(gen, s, len);
 272                         lex_read_to(s + len);
 273                         lex_read_space(0);
 274                         c = lex_peek_unichar(0);
 275                         if (c == '(') {
 276                                 sv = sv_2mortal(newSVpvs(""));
 277                                 if (!S_scan_str(aTHX_ sv, TRUE, TRUE)) {
 278                                         croak("In %"SVf": malformed attribute argument list", SVfARG(declarator));
 279                                 }
 280                                 sv_catsv(gen, sv);
 281                                 lex_read_space(0);
 282                                 c = lex_peek_unichar(0);
 283                         }
 284                         if (c == ':') {
 285                                 lex_read_unichar(0);
 286                                 lex_read_space(0);
 287                         }
 288                 }
 289         }
 290
 291         /* body */
 292         c = lex_peek_unichar(0);
 293         if (c != '{') {
 294                 croak("In %"SVf": I was expecting a function body, not \"%c\"", SVfARG(declarator), (int)c);
 295         }
 296         lex_read_unichar(0);
 297         sv_catpvs(gen, "{");
 298         if (SvTRUE(spec->shift)) {
 299                 sv_catpvs(gen, "my");
 300                 sv_catsv(gen, spec->shift);
 301                 sv_catpvs(gen, "=shift;");
 302         }
 303         if (SvCUR(params)) {
 304                 sv_catpvs(gen, "my(");
 305                 sv_catsv(gen, params);
 306                 sv_catpvs(gen, ")=@_;");
 307         }
 308
 309         /* named sub */
 310         if (saw_name) {
 311                 /* fprintf(stderr, "! [%.*s]\n", (int)(PL_bufend - PL_bufptr), PL_bufptr); */
 312                 lex_stuff_sv(gen, SvUTF8(gen));
 313                 *pop = parse_barestmt(0);
 314                 return KEYWORD_PLUGIN_STMT;
 315         }
 316
 317         /* anon sub */
 318         sv_catpvs(gen, "BEGIN{" MY_PKG "::_fini}");
 319         /* fprintf(stderr, "!> [%.*s]\n", (int)(PL_bufend - PL_bufptr), PL_bufptr); */
 320         lex_stuff_sv(gen, SvUTF8(gen));
 321         *pop = parse_arithexpr(0);
 322         s = PL_parser->bufptr;
 323         if (*s != '}') {
 324                 croak("%s: internal error: expected '}', found '%c'", MY_PKG, *s);
 325         }
 326         lex_unstuff(s + 1);
 327         /* fprintf(stderr, "!< [%.*s]\n", (int)(PL_bufend - PL_bufptr), PL_bufptr); */
 328         return KEYWORD_PLUGIN_EXPR;
 329 }
 330
 331 static int my_keyword_plugin(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr) {
 332         Spec spec;
 333         int ret;
 334
 335         SAVETMPS;
 336
 337         if (kw_flags(aTHX_ keyword_ptr, keyword_len, &spec)) {
 338                 ret = parse_fun(aTHX_ op_ptr, keyword_ptr, keyword_len, &spec);
 339         } else {
 340                 ret = next_keyword_plugin(aTHX_ keyword_ptr, keyword_len, op_ptr);
 341         }
 342
 343         FREETMPS;
 344
 345         return ret;
 346 }
 347
 348 static int magic_free(pTHX_ SV *sv, MAGIC *mg) {
 349         lex_stuff_pvn("}", 1, 0);
 350         /* fprintf(stderr, "!~ [%.*s]\n", (int)(PL_bufend - PL_bufptr), PL_bufptr); */
 351         return 0;
 352 }
 353
 354 static int magic_nop(pTHX_ SV *sv, MAGIC *mg) {
 355         return 0;
 356 }
 357
 358 static MGVTBL my_vtbl = {
 359         0,           /* get   */
 360         0,           /* set   */
 361         0,           /* len   */
 362         0,           /* clear */
 363         magic_free,  /* free  */
 364         0,           /* copy  */
 365         0,           /* dup   */
 366         magic_nop    /* local */
 367 };
 368
 369 WARNINGS_RESET
 370
 371 MODULE = Function::Parameters   PACKAGE = Function::Parameters
 372 PROTOTYPES: ENABLE
 373
 374 BOOT:
 375 WARNINGS_ENABLE {
 376         HV *const stash = gv_stashpvs(MY_PKG, GV_ADD);
 377         /**/
 378         newCONSTSUB(stash, "FLAG_NAME_OPTIONAL", newSViv(FLAG_NAME_OPTIONAL));
 379         newCONSTSUB(stash, "FLAG_NAME_REQUIRED", newSViv(FLAG_NAME_REQUIRED));
 380         newCONSTSUB(stash, "FLAG_NAME_PROHIBITED", newSViv(FLAG_NAME_PROHIBITED));
 381         newCONSTSUB(stash, "HINTK_KEYWORDS", newSVpvs(HINTK_KEYWORDS));
 382         newCONSTSUB(stash, "HINTK_NAME_", newSVpvs(HINTK_NAME_));
 383         newCONSTSUB(stash, "HINTK_SHIFT_", newSVpvs(HINTK_SHIFT_));
 384         newCONSTSUB(stash, "HINTK_ATTRS_", newSVpvs(HINTK_ATTRS_));
 385         /**/
 386         next_keyword_plugin = PL_keyword_plugin;
 387         PL_keyword_plugin = my_keyword_plugin;
 388 } WARNINGS_RESET
 389
 390 void
 391 _fini()
 392         CODE:
 393         sv_magicext((SV *)GvHV(PL_hintgv), NULL, PERL_MAGIC_ext, &my_vtbl, NULL, 0);