git.m6w6.name Git - m6w6/ext-psi/blob - src/libffi.c

   1 #ifdef HAVE_CONFIG_H
   2 # include "config.h"
   3 #endif
   4
   5 #include "php.h"
   6
   7 #ifdef HAVE_LIBFFI
   8
   9 #include "php_psi.h"
  10 #include "libffi.h"
  11 #include "engine.h"
  12
  13 #undef PACKAGE
  14 #undef PACKAGE_BUGREPORT
  15 #undef PACKAGE_NAME
  16 #undef PACKAGE_STRING
  17 #undef PACKAGE_TARNAME
  18 #undef PACKAGE_VERSION
  19
  20 #include <ffi.h>
  21
  22 #ifndef PSI_HAVE_FFI_CLOSURE_ALLOC
  23 # if HAVE_UNISTD_H
  24 #  include <unistd.h>
  25 # endif
  26 # if HAVE_SYS_MMAN_H
  27 #  include <sys/mman.h>
  28 #  ifndef MAP_ANONYMOUS
  29 #   define MAP_ANONYMOUS MAP_ANON
  30 #  endif
  31 # endif
  32 #endif
  33
  34 static void *psi_ffi_closure_alloc(size_t s, void **code)
  35 {
  36 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  37         return ffi_closure_alloc(s, code);
  38 #elif HAVE_MMAP
  39         *code = mmap(NULL, s, PROT_EXEC|PROT_WRITE|PROT_READ,
  40                         MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  41         if (MAP_FAILED == *code) {
  42                 return NULL;
  43         }
  44         return *code;
  45 #else
  46 # error "Neither ffi_closure_alloc() nor mmap() available"
  47 #endif
  48 }
  49
  50 static ffi_status psi_ffi_prep_closure(ffi_closure **closure, void **code, ffi_cif *sig, void (*handler)(ffi_cif*,void*,void**,void*), void *data) {
  51         *closure = psi_ffi_closure_alloc(sizeof(ffi_closure), code);
  52         ZEND_ASSERT(*closure != NULL);
  53
  54 #if PSI_HAVE_FFI_PREP_CLOSURE_LOC
  55         return ffi_prep_closure_loc(*closure, sig, handler, data, *code);
  56
  57 #elif PSI_HAVE_FFI_PREP_CLOSURE
  58         return ffi_prep_closure(*code, sig, handler, data);
  59 #else
  60 # error "Neither ffi_prep_closure() nor ffi_prep_closure_loc() is available"
  61 #endif
  62
  63 }
  64
  65 static void psi_ffi_closure_free(void *c)
  66 {
  67 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  68         ffi_closure_free(c);
  69 #elif HAVE_MMAP
  70         munmap(c, sizeof(ffi_closure));
  71 #endif
  72 }
  73
  74 static void psi_ffi_handler(ffi_cif *_sig, void *_result, void **_args, void *_data)
  75 {
  76         psi_call(*(zend_execute_data **)_args[0], *(zval **)_args[1], _data);
  77 }
  78
  79 static void psi_ffi_callback(ffi_cif *_sig, void *_result, void **_args, void *_data)
  80 {
  81         size_t i;
  82         unsigned argc = _sig->nargs;
  83         void **argv = _args;
  84         let_callback *cb = _data;
  85         decl *decl_cb = cb->decl;
  86         impl_arg *iarg = cb->func->var->arg;
  87         zval return_value, *zargv = calloc(argc, sizeof(*zargv));
  88         void *result, *to_free = NULL;
  89
  90         ZEND_ASSERT(argc == cb->decl->args->count);
  91
  92         /* prepare args for the userland call */
  93         for (i = 0; i < argc; ++i) {
  94                 cb->decl->args->args[i]->ptr = argv[i];
  95         }
  96         for (i = 0; i < cb->args->count; ++i) {
  97                 psi_do_set(&zargv[i], cb->args->vals[i]);
  98         }
  99         zend_fcall_info_argp(&iarg->val.zend.cb->fci, cb->args->count, zargv);
 100
 101         /* callback into userland */
 102         ZVAL_UNDEF(&return_value);
 103         iarg->_zv = &return_value;
 104         zend_fcall_info_call(&iarg->val.zend.cb->fci, &iarg->val.zend.cb->fcc, iarg->_zv, NULL);
 105
 106         /* marshal return value of the userland call */
 107         switch (iarg->type->type) {
 108         case PSI_T_BOOL:        zend_parse_arg_bool(iarg->_zv, &iarg->val.zend.bval, NULL, 0);          break;
 109         case PSI_T_LONG:        zend_parse_arg_long(iarg->_zv, &iarg->val.zend.lval, NULL, 0, 1);       break;
 110         case PSI_T_FLOAT:
 111         case PSI_T_DOUBLE:      zend_parse_arg_double(iarg->_zv, &iarg->val.dval, NULL, 0);                     break;
 112         case PSI_T_STRING:      zend_parse_arg_str(iarg->_zv, &iarg->val.zend.str, 0);                          break;
 113         }
 114         result = cb->func->handler(_result, decl_cb->func->type, iarg, &to_free);
 115
 116         if (result != _result) {
 117                 *(void **)_result = result;
 118         }
 119 }
 120
 121 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg);
 122
 123 typedef struct PSI_LibffiContext {
 124         ffi_cif signature;
 125         ffi_type *params[2];
 126 } PSI_LibffiContext;
 127
 128 typedef struct PSI_LibffiCall {
 129         void *code;
 130         ffi_closure *closure;
 131         ffi_cif signature;
 132         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 133 } PSI_LibffiCall;
 134
 135 static inline ffi_abi psi_ffi_abi(const char *convention) {
 136         return FFI_DEFAULT_ABI;
 137 }
 138
 139 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 140         int rc;
 141         size_t i, c = decl->args ? decl->args->count : 0;
 142         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 143
 144         for (i = 0; i < c; ++i) {
 145                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 146         }
 147         call->params[c] = NULL;
 148
 149         decl->call.info = call;
 150         decl->call.rval = &decl->func->ptr;
 151         decl->call.argc = c;
 152         decl->call.args = (void **) &call->params[c+1];
 153
 154         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 155                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 156         ZEND_ASSERT(FFI_OK == rc);
 157
 158         return call;
 159 }
 160
 161 static inline ffi_status PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 162         PSI_LibffiContext *context = C->context;
 163
 164         return psi_ffi_prep_closure(&call->closure, &call->code, &context->signature, psi_ffi_handler, impl);
 165 }
 166
 167 static inline ffi_status PSI_LibffiCallInitCallbackClosure(PSI_Context *C, PSI_LibffiCall *call, let_callback *cb) {
 168         return psi_ffi_prep_closure(&call->closure, &call->code, &call->signature, psi_ffi_callback, cb);
 169 }
 170
 171 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 172         if (call->closure) {
 173                 psi_ffi_closure_free(call->closure);
 174         }
 175         free(call);
 176 }
 177
 178 static inline ffi_type *psi_ffi_token_type(token_t t) {
 179         switch (t) {
 180         default:
 181                 ZEND_ASSERT(0);
 182                 /* no break */
 183         case PSI_T_VOID:
 184                 return &ffi_type_void;
 185         case PSI_T_INT8:
 186                 return &ffi_type_sint8;
 187         case PSI_T_UINT8:
 188                 return &ffi_type_uint8;
 189         case PSI_T_INT16:
 190                 return &ffi_type_sint16;
 191         case PSI_T_UINT16:
 192                 return &ffi_type_uint16;
 193         case PSI_T_INT32:
 194                 return &ffi_type_sint32;
 195         case PSI_T_UINT32:
 196                 return &ffi_type_uint32;
 197         case PSI_T_INT64:
 198                 return &ffi_type_sint64;
 199         case PSI_T_UINT64:
 200                 return &ffi_type_uint64;
 201         case PSI_T_BOOL:
 202                 return &ffi_type_uchar;
 203         case PSI_T_INT:
 204         case PSI_T_ENUM:
 205                 return &ffi_type_sint;
 206         case PSI_T_LONG:
 207                 return &ffi_type_slong;
 208         case PSI_T_FLOAT:
 209                 return &ffi_type_float;
 210         case PSI_T_DOUBLE:
 211                 return &ffi_type_double;
 212 #ifdef HAVE_LONG_DOUBLE
 213         case PSI_T_LONG_DOUBLE:
 214                 return &ffi_type_longdouble;
 215 #endif
 216         case PSI_T_POINTER:
 217         case PSI_T_FUNCTION:
 218                 return &ffi_type_pointer;
 219         }
 220 }
 221 static inline ffi_type *psi_ffi_impl_type(token_t impl_type) {
 222         switch (impl_type) {
 223         case PSI_T_BOOL:
 224                 return &ffi_type_sint8;
 225         case PSI_T_INT:
 226                 return &ffi_type_sint64;
 227         case PSI_T_STRING:
 228                 return &ffi_type_pointer;
 229         case PSI_T_FLOAT:
 230         case PSI_T_DOUBLE:
 231                 return &ffi_type_double;
 232         EMPTY_SWITCH_DEFAULT_CASE();
 233         }
 234         return NULL;
 235 }
 236 static void psi_ffi_struct_type_dtor(void *type) {
 237         ffi_type *strct = type;
 238
 239         if (strct->elements) {
 240                 ffi_type **ptr;
 241
 242                 for (ptr = strct->elements; *ptr; ++ptr) {
 243                         free(*ptr);
 244                 }
 245                 free(strct->elements);
 246         }
 247         free(strct);
 248 }
 249
 250 static size_t psi_ffi_struct_type_pad(ffi_type **els, size_t padding) {
 251         size_t i;
 252
 253         for (i = 0; i < padding; ++i) {
 254                 ffi_type *pad = malloc(sizeof(*pad));
 255
 256                 memcpy(pad, &ffi_type_schar, sizeof(*pad));
 257                 *els++ = pad;
 258         }
 259
 260         return padding;
 261 }
 262
 263 static ffi_type **psi_ffi_struct_type_elements(decl_struct *strct) {
 264         size_t i, argc = strct->args->count, nels = 0, offset = 0, maxalign = 0;
 265         ffi_type **els = calloc(argc + 1, sizeof(*els));
 266
 267         for (i = 0; i < strct->args->count; ++i) {
 268                 decl_arg *darg = strct->args->args[i];
 269                 ffi_type *type = malloc(sizeof(*type));
 270                 size_t padding;
 271
 272                 memcpy(type, psi_ffi_decl_arg_type(darg), sizeof(*type));
 273
 274                 ZEND_ASSERT(type->size == darg->layout->len);
 275
 276                 if (type->alignment > maxalign) {
 277                         maxalign = type->alignment;
 278                 }
 279
 280                 if ((padding = psi_offset_padding(darg->layout->pos - offset, type->alignment))) {
 281                         if (nels + padding + 1 > argc) {
 282                                 argc += padding;
 283                                 els = realloc(els, (argc + 1) * sizeof(*els));
 284                                 els[argc] = NULL;
 285                         }
 286                         psi_ffi_struct_type_pad(&els[nels], padding);
 287                         nels += padding;
 288                         offset += padding;
 289                 }
 290                 ZEND_ASSERT(offset == darg->layout->pos);
 291
 292                 offset = (offset + darg->layout->len + type->alignment - 1) & ~(type->alignment - 1);
 293                 els[nels++] = type;
 294         }
 295
 296         /* apply struct alignment padding */
 297         offset = (offset + maxalign - 1) & ~(maxalign - 1);
 298
 299         ZEND_ASSERT(offset <= strct->size);
 300         if (offset < strct->size) {
 301                 psi_ffi_struct_type_pad(&els[nels], strct->size - offset);
 302         }
 303
 304         return els;
 305 }
 306 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
 307         decl_type *real = real_decl_type(type);
 308
 309         switch (real->type) {
 310         case PSI_T_FUNCTION:
 311                 return &ffi_type_pointer;
 312
 313         case PSI_T_STRUCT:
 314                 if (!real->strct->engine.type) {
 315                         ffi_type *strct = calloc(1, sizeof(ffi_type));
 316
 317                         strct->type = FFI_TYPE_STRUCT;
 318                         strct->size = 0;
 319                         strct->elements = psi_ffi_struct_type_elements(real->strct);
 320
 321                         real->strct->engine.type = strct;
 322                         real->strct->engine.dtor = psi_ffi_struct_type_dtor;
 323                 }
 324
 325                 return real->strct->engine.type;
 326
 327         case PSI_T_UNION:
 328                 return psi_ffi_decl_arg_type(real->unn->args->args[0]);
 329
 330         default:
 331                 return psi_ffi_token_type(real->type);
 332         }
 333 }
 334 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 335         if (darg->var->pointer_level) {
 336                 return &ffi_type_pointer;
 337         } else {
 338                 return psi_ffi_decl_type(darg->type);
 339         }
 340 }
 341
 342
 343 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 344         ffi_status rc;
 345
 346         if (!L) {
 347                 L = malloc(sizeof(*L));
 348         }
 349         memset(L, 0, sizeof(*L));
 350
 351         L->params[0] = &ffi_type_pointer;
 352         L->params[1] = &ffi_type_pointer;
 353         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 354         ZEND_ASSERT(rc == FFI_OK);
 355
 356         return L;
 357 }
 358
 359 static void psi_ffi_init(PSI_Context *C)
 360 {
 361         C->context = PSI_LibffiContextInit(NULL);
 362 }
 363
 364 static void psi_ffi_dtor(PSI_Context *C)
 365 {
 366         if (C->decls) {
 367                 size_t i;
 368
 369                 for (i = 0; i < C->decls->count; ++i) {
 370                         decl *decl = C->decls->list[i];
 371
 372                         if (decl->call.info) {
 373                                 PSI_LibffiCallFree(decl->call.info);
 374                         }
 375                 }
 376         }
 377         free(C->context);
 378 }
 379
 380 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 381 {
 382         size_t c, i, j = 0;
 383         zend_function_entry *zfe;
 384
 385         if (!C->impls) {
 386                 return NULL;
 387         }
 388
 389         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 390         for (i = 0; i < C->impls->count; ++i) {
 391                 zend_function_entry *zf = &zfe[j];
 392                 PSI_LibffiCall *call;
 393                 impl *impl = C->impls->list[i];
 394
 395                 if (!impl->decl) {
 396                         continue;
 397                 }
 398
 399                 call = PSI_LibffiCallAlloc(C, impl->decl);
 400                 if (FFI_OK != PSI_LibffiCallInitClosure(C, call, impl)) {
 401                         PSI_LibffiCallFree(call);
 402                         continue;
 403                 }
 404
 405                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 406                 zf->num_args = impl->func->args->count;
 407                 zf->handler = call->code;
 408                 zf->arg_info = psi_internal_arginfo(impl);
 409                 ++j;
 410
 411                 for (c = 0; c < impl->stmts->let.count; ++c) {
 412                         let_stmt *let = impl->stmts->let.list[c];
 413
 414                         if (let->val->kind == PSI_LET_CALLBACK) {
 415                                 let_callback *cb = let->val->data.callback;
 416
 417                                 call = PSI_LibffiCallAlloc(C, cb->decl);
 418                                 if (FFI_OK != PSI_LibffiCallInitCallbackClosure(C, call, cb)) {
 419                                         PSI_LibffiCallFree(call);
 420                                         continue;
 421                                 }
 422
 423                                 cb->decl->call.sym = call->code;
 424                         }
 425                 }
 426         }
 427
 428         for (i = 0; i < C->decls->count; ++i) {
 429                 decl *decl = C->decls->list[i];
 430
 431 //              if (decl->impl) {
 432 //                      continue;
 433 //              }
 434                 if (decl->call.info) {
 435                         continue;
 436                 }
 437
 438                 PSI_LibffiCallAlloc(C, decl);
 439         }
 440
 441         return zfe;
 442 }
 443
 444 static void psi_ffi_call(PSI_Context *C, decl_callinfo *decl_call, impl_vararg *va) {
 445         PSI_LibffiCall *call = decl_call->info;
 446
 447         if (va) {
 448                 ffi_status rc;
 449                 ffi_cif signature;
 450                 size_t i, nfixedargs = decl_call->argc, ntotalargs = nfixedargs + va->args->count;
 451                 void **params = calloc(2 * ntotalargs + 2, sizeof(void *));
 452
 453                 for (i = 0; i < nfixedargs; ++i) {
 454                         params[i] = call->params[i];
 455                         params[i + ntotalargs + 1] = call->params[i + nfixedargs + 1];
 456                 }
 457                 for (i = 0; i < va->args->count; ++i) {
 458                         params[nfixedargs + i] = psi_ffi_impl_type(va->types[i]);
 459                         params[nfixedargs + i + ntotalargs + 1] = &va->values[i];
 460                 }
 461 #ifdef PSI_HAVE_FFI_PREP_CIF_VAR
 462                 rc = ffi_prep_cif_var(&signature, call->signature.abi,
 463                                 nfixedargs, ntotalargs,
 464                                 call->signature.rtype, (ffi_type **) params);
 465 #else
 466                 /* FIXME: test in config.m4; assume we can just call anyway */
 467                 rc = ffi_prep_cif(&signature, call->signature.abi, ntotalargs,
 468                                 call->signature.rtype, (ffi_type **) params);
 469 #endif
 470                 ZEND_ASSERT(FFI_OK == rc);
 471                 ffi_call(&signature, FFI_FN(decl_call->sym), *decl_call->rval, &params[ntotalargs + 1]);
 472                 free(params);
 473         } else {
 474                 ffi_call(&call->signature, FFI_FN(decl_call->sym), *decl_call->rval, decl_call->args);
 475         }
 476 }
 477
 478 static PSI_ContextOps ops = {
 479         psi_ffi_init,
 480         psi_ffi_dtor,
 481         psi_ffi_compile,
 482         psi_ffi_call,
 483 };
 484
 485 PSI_ContextOps *PSI_Libffi(void)
 486 {
 487         return &ops;
 488 }
 489
 490 #endif /* HAVE_LIBFFI */