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]->let = 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         zend_fcall_info_args_clear(&iarg->val.zend.cb->fci, 0);
 121         for (i = 0; i < cb->args->count; ++i) {
 122                 zval_ptr_dtor(&zargv[i]);
 123         }
 124         free(zargv);
 125 }
 126
 127 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg);
 128
 129 typedef struct PSI_LibffiContext {
 130         ffi_cif signature;
 131         ffi_type *params[2];
 132 } PSI_LibffiContext;
 133
 134 typedef struct PSI_LibffiCall {
 135         void *code;
 136         ffi_closure *closure;
 137         ffi_cif signature;
 138         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 139 } PSI_LibffiCall;
 140
 141 static inline ffi_abi psi_ffi_abi(const char *convention) {
 142         return FFI_DEFAULT_ABI;
 143 }
 144
 145 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 146         int rc;
 147         size_t i, c = decl->args ? decl->args->count : 0;
 148         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 149
 150         for (i = 0; i < c; ++i) {
 151                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 152         }
 153         call->params[c] = NULL;
 154
 155         decl->call.info = call;
 156         decl->call.rval = &decl->func->ptr;
 157         decl->call.argc = c;
 158         decl->call.args = (void **) &call->params[c+1];
 159
 160         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 161                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 162         ZEND_ASSERT(FFI_OK == rc);
 163
 164         return call;
 165 }
 166
 167 static inline ffi_status PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 168         PSI_LibffiContext *context = C->context;
 169
 170         return psi_ffi_prep_closure(&call->closure, &call->code, &context->signature, psi_ffi_handler, impl);
 171 }
 172
 173 static inline ffi_status PSI_LibffiCallInitCallbackClosure(PSI_Context *C, PSI_LibffiCall *call, let_callback *cb) {
 174         return psi_ffi_prep_closure(&call->closure, &call->code, &call->signature, psi_ffi_callback, cb);
 175 }
 176
 177 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 178         if (call->closure) {
 179                 psi_ffi_closure_free(call->closure);
 180         }
 181         free(call);
 182 }
 183
 184 static inline ffi_type *psi_ffi_token_type(token_t t) {
 185         switch (t) {
 186         default:
 187                 ZEND_ASSERT(0);
 188                 /* no break */
 189         case PSI_T_VOID:
 190                 return &ffi_type_void;
 191         case PSI_T_INT8:
 192                 return &ffi_type_sint8;
 193         case PSI_T_UINT8:
 194                 return &ffi_type_uint8;
 195         case PSI_T_INT16:
 196                 return &ffi_type_sint16;
 197         case PSI_T_UINT16:
 198                 return &ffi_type_uint16;
 199         case PSI_T_INT32:
 200                 return &ffi_type_sint32;
 201         case PSI_T_UINT32:
 202                 return &ffi_type_uint32;
 203         case PSI_T_INT64:
 204                 return &ffi_type_sint64;
 205         case PSI_T_UINT64:
 206                 return &ffi_type_uint64;
 207         case PSI_T_BOOL:
 208                 return &ffi_type_uchar;
 209         case PSI_T_INT:
 210         case PSI_T_ENUM:
 211                 return &ffi_type_sint;
 212         case PSI_T_LONG:
 213                 return &ffi_type_slong;
 214         case PSI_T_FLOAT:
 215                 return &ffi_type_float;
 216         case PSI_T_DOUBLE:
 217                 return &ffi_type_double;
 218 #ifdef HAVE_LONG_DOUBLE
 219         case PSI_T_LONG_DOUBLE:
 220                 return &ffi_type_longdouble;
 221 #endif
 222         case PSI_T_POINTER:
 223         case PSI_T_FUNCTION:
 224                 return &ffi_type_pointer;
 225         }
 226 }
 227 static inline ffi_type *psi_ffi_impl_type(token_t impl_type) {
 228         switch (impl_type) {
 229         case PSI_T_BOOL:
 230                 return &ffi_type_sint8;
 231         case PSI_T_INT:
 232                 return &ffi_type_sint64;
 233         case PSI_T_STRING:
 234                 return &ffi_type_pointer;
 235         case PSI_T_FLOAT:
 236         case PSI_T_DOUBLE:
 237                 return &ffi_type_double;
 238         EMPTY_SWITCH_DEFAULT_CASE();
 239         }
 240         return NULL;
 241 }
 242 static void psi_ffi_struct_type_dtor(void *type) {
 243         ffi_type *strct = type;
 244
 245         if (strct->elements) {
 246                 ffi_type **ptr;
 247
 248                 for (ptr = strct->elements; *ptr; ++ptr) {
 249                         free(*ptr);
 250                 }
 251                 free(strct->elements);
 252         }
 253         free(strct);
 254 }
 255
 256 static size_t psi_ffi_struct_type_pad(ffi_type **els, size_t padding) {
 257         size_t i;
 258
 259         for (i = 0; i < padding; ++i) {
 260                 ffi_type *pad = malloc(sizeof(*pad));
 261
 262                 memcpy(pad, &ffi_type_schar, sizeof(*pad));
 263                 *els++ = pad;
 264         }
 265
 266         return padding;
 267 }
 268
 269 static ffi_type **psi_ffi_struct_type_elements(decl_struct *strct) {
 270         size_t i, argc = strct->args->count, nels = 0, offset = 0, maxalign = 0;
 271         ffi_type **els = calloc(argc + 1, sizeof(*els));
 272
 273         for (i = 0; i < strct->args->count; ++i) {
 274                 decl_arg *darg = strct->args->args[i];
 275                 ffi_type *type = malloc(sizeof(*type));
 276                 size_t padding;
 277
 278                 memcpy(type, psi_ffi_decl_arg_type(darg), sizeof(*type));
 279
 280                 ZEND_ASSERT(type->size == darg->layout->len);
 281
 282                 if (type->alignment > maxalign) {
 283                         maxalign = type->alignment;
 284                 }
 285
 286                 if ((padding = psi_offset_padding(darg->layout->pos - offset, type->alignment))) {
 287                         if (nels + padding + 1 > argc) {
 288                                 argc += padding;
 289                                 els = realloc(els, (argc + 1) * sizeof(*els));
 290                                 els[argc] = NULL;
 291                         }
 292                         psi_ffi_struct_type_pad(&els[nels], padding);
 293                         nels += padding;
 294                         offset += padding;
 295                 }
 296                 ZEND_ASSERT(offset == darg->layout->pos);
 297
 298                 offset = (offset + darg->layout->len + type->alignment - 1) & ~(type->alignment - 1);
 299                 els[nels++] = type;
 300         }
 301
 302         /* apply struct alignment padding */
 303         offset = (offset + maxalign - 1) & ~(maxalign - 1);
 304
 305         ZEND_ASSERT(offset <= strct->size);
 306         if (offset < strct->size) {
 307                 psi_ffi_struct_type_pad(&els[nels], strct->size - offset);
 308         }
 309
 310         return els;
 311 }
 312 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
 313         decl_type *real = real_decl_type(type);
 314
 315         switch (real->type) {
 316         case PSI_T_FUNCTION:
 317                 return &ffi_type_pointer;
 318
 319         case PSI_T_STRUCT:
 320                 if (!real->strct->engine.type) {
 321                         ffi_type *strct = calloc(1, sizeof(ffi_type));
 322
 323                         strct->type = FFI_TYPE_STRUCT;
 324                         strct->size = 0;
 325                         strct->elements = psi_ffi_struct_type_elements(real->strct);
 326
 327                         real->strct->engine.type = strct;
 328                         real->strct->engine.dtor = psi_ffi_struct_type_dtor;
 329                 }
 330
 331                 return real->strct->engine.type;
 332
 333         case PSI_T_UNION:
 334                 return psi_ffi_decl_arg_type(real->unn->args->args[0]);
 335
 336         default:
 337                 return psi_ffi_token_type(real->type);
 338         }
 339 }
 340 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 341         if (darg->var->pointer_level) {
 342                 return &ffi_type_pointer;
 343         } else {
 344                 return psi_ffi_decl_type(darg->type);
 345         }
 346 }
 347
 348
 349 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 350         ffi_status rc;
 351
 352         if (!L) {
 353                 L = malloc(sizeof(*L));
 354         }
 355         memset(L, 0, sizeof(*L));
 356
 357         L->params[0] = &ffi_type_pointer;
 358         L->params[1] = &ffi_type_pointer;
 359         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 360         ZEND_ASSERT(rc == FFI_OK);
 361
 362         return L;
 363 }
 364
 365 static void psi_ffi_init(PSI_Context *C)
 366 {
 367         C->context = PSI_LibffiContextInit(NULL);
 368 }
 369
 370 static void psi_ffi_dtor(PSI_Context *C)
 371 {
 372         if (C->decls) {
 373                 size_t i;
 374
 375                 for (i = 0; i < C->decls->count; ++i) {
 376                         decl *decl = C->decls->list[i];
 377
 378                         if (decl->call.info) {
 379                                 PSI_LibffiCallFree(decl->call.info);
 380                         }
 381                 }
 382
 383         }
 384         if (C->impls) {
 385                 size_t i, j;
 386
 387                 for (i = 0; i < C->impls->count; ++i) {
 388                         impl *impl = C->impls->list[i];
 389
 390                         for (j = 0; j < impl->stmts->let.count; ++j) {
 391                                 let_stmt *let = impl->stmts->let.list[j];
 392
 393                                 if (let->val && let->val->kind == PSI_LET_CALLBACK) {
 394                                         let_callback *cb = let->val->data.callback;
 395
 396                                         if (cb->decl && cb->decl->call.info) {
 397                                                 PSI_LibffiCallFree(cb->decl->call.info);
 398                                         }
 399                                 }
 400                         }
 401                 }
 402         }
 403         free(C->context);
 404 }
 405
 406 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 407 {
 408         size_t c, i, j = 0;
 409         zend_function_entry *zfe;
 410
 411         if (!C->impls) {
 412                 return NULL;
 413         }
 414
 415         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 416         for (i = 0; i < C->impls->count; ++i) {
 417                 zend_function_entry *zf = &zfe[j];
 418                 PSI_LibffiCall *call;
 419                 impl *impl = C->impls->list[i];
 420
 421                 if (!impl->decl) {
 422                         continue;
 423                 }
 424
 425                 call = PSI_LibffiCallAlloc(C, impl->decl);
 426                 if (FFI_OK != PSI_LibffiCallInitClosure(C, call, impl)) {
 427                         PSI_LibffiCallFree(call);
 428                         continue;
 429                 }
 430
 431                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 432                 zf->num_args = impl->func->args->count;
 433                 zf->handler = call->code;
 434                 zf->arg_info = psi_internal_arginfo(impl);
 435                 ++j;
 436
 437                 for (c = 0; c < impl->stmts->let.count; ++c) {
 438                         let_stmt *let = impl->stmts->let.list[c];
 439
 440                         if (let->val->kind == PSI_LET_CALLBACK) {
 441                                 let_callback *cb = let->val->data.callback;
 442
 443                                 call = PSI_LibffiCallAlloc(C, cb->decl);
 444                                 if (FFI_OK != PSI_LibffiCallInitCallbackClosure(C, call, cb)) {
 445                                         PSI_LibffiCallFree(call);
 446                                         continue;
 447                                 }
 448
 449                                 cb->decl->call.sym = call->code;
 450                         }
 451                 }
 452         }
 453
 454         for (i = 0; i < C->decls->count; ++i) {
 455                 decl *decl = C->decls->list[i];
 456
 457 //              if (decl->impl) {
 458 //                      continue;
 459 //              }
 460                 if (decl->call.info) {
 461                         continue;
 462                 }
 463
 464                 PSI_LibffiCallAlloc(C, decl);
 465         }
 466
 467         return zfe;
 468 }
 469
 470 static void psi_ffi_call(PSI_Context *C, decl_callinfo *decl_call, impl_vararg *va) {
 471         PSI_LibffiCall *call = decl_call->info;
 472
 473         if (va) {
 474                 ffi_status rc;
 475                 ffi_cif signature;
 476                 size_t i, nfixedargs = decl_call->argc, ntotalargs = nfixedargs + va->args->count;
 477                 void **params = calloc(2 * ntotalargs + 2, sizeof(void *));
 478
 479                 for (i = 0; i < nfixedargs; ++i) {
 480                         params[i] = call->params[i];
 481                         params[i + ntotalargs + 1] = call->params[i + nfixedargs + 1];
 482                 }
 483                 for (i = 0; i < va->args->count; ++i) {
 484                         params[nfixedargs + i] = psi_ffi_impl_type(va->types[i]);
 485                         params[nfixedargs + i + ntotalargs + 1] = &va->values[i];
 486                 }
 487 #ifdef PSI_HAVE_FFI_PREP_CIF_VAR
 488                 rc = ffi_prep_cif_var(&signature, call->signature.abi,
 489                                 nfixedargs, ntotalargs,
 490                                 call->signature.rtype, (ffi_type **) params);
 491 #else
 492                 /* FIXME: test in config.m4; assume we can just call anyway */
 493                 rc = ffi_prep_cif(&signature, call->signature.abi, ntotalargs,
 494                                 call->signature.rtype, (ffi_type **) params);
 495 #endif
 496                 ZEND_ASSERT(FFI_OK == rc);
 497                 ffi_call(&signature, FFI_FN(decl_call->sym), *decl_call->rval, &params[ntotalargs + 1]);
 498                 free(params);
 499         } else {
 500                 ffi_call(&call->signature, FFI_FN(decl_call->sym), *decl_call->rval, decl_call->args);
 501         }
 502 }
 503
 504 static PSI_ContextOps ops = {
 505         psi_ffi_init,
 506         psi_ffi_dtor,
 507         psi_ffi_compile,
 508         psi_ffi_call,
 509 };
 510
 511 PSI_ContextOps *PSI_Libffi(void)
 512 {
 513         return &ops;
 514 }
 515
 516 #endif /* HAVE_LIBFFI */