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         psi_callback(_data, _result, _sig->nargs, _args);
  82 }
  83
  84 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg);
  85
  86 typedef struct PSI_LibffiContext {
  87         ffi_cif signature;
  88         ffi_type *params[2];
  89 } PSI_LibffiContext;
  90
  91 typedef struct PSI_LibffiCall {
  92         void *code;
  93         ffi_closure *closure;
  94         ffi_cif signature;
  95         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
  96 } PSI_LibffiCall;
  97
  98 static inline ffi_abi psi_ffi_abi(const char *convention) {
  99         return FFI_DEFAULT_ABI;
 100 }
 101
 102 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 103         int rc;
 104         size_t i, c = decl->args ? decl->args->count : 0;
 105         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 106
 107         for (i = 0; i < c; ++i) {
 108                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 109         }
 110         call->params[c] = NULL;
 111
 112         decl->call.info = call;
 113         decl->call.rval = &decl->func->ptr;
 114         decl->call.argc = c;
 115         decl->call.args = (void **) &call->params[c+1];
 116
 117         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 118                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 119         ZEND_ASSERT(FFI_OK == rc);
 120
 121         return call;
 122 }
 123
 124 static inline ffi_status PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 125         PSI_LibffiContext *context = C->context;
 126
 127         return psi_ffi_prep_closure(&call->closure, &call->code, &context->signature, psi_ffi_handler, impl);
 128 }
 129
 130 static inline ffi_status PSI_LibffiCallInitCallbackClosure(PSI_Context *C, PSI_LibffiCall *call, let_callback *cb) {
 131         return psi_ffi_prep_closure(&call->closure, &call->code, &call->signature, psi_ffi_callback, cb);
 132 }
 133
 134 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 135         if (call->closure) {
 136                 psi_ffi_closure_free(call->closure);
 137         }
 138         free(call);
 139 }
 140
 141 static inline ffi_type *psi_ffi_token_type(token_t t) {
 142         switch (t) {
 143         default:
 144                 ZEND_ASSERT(0);
 145                 /* no break */
 146         case PSI_T_VOID:
 147                 return &ffi_type_void;
 148         case PSI_T_INT8:
 149                 return &ffi_type_sint8;
 150         case PSI_T_UINT8:
 151                 return &ffi_type_uint8;
 152         case PSI_T_INT16:
 153                 return &ffi_type_sint16;
 154         case PSI_T_UINT16:
 155                 return &ffi_type_uint16;
 156         case PSI_T_INT32:
 157                 return &ffi_type_sint32;
 158         case PSI_T_UINT32:
 159                 return &ffi_type_uint32;
 160         case PSI_T_INT64:
 161                 return &ffi_type_sint64;
 162         case PSI_T_UINT64:
 163                 return &ffi_type_uint64;
 164         case PSI_T_BOOL:
 165                 return &ffi_type_uchar;
 166         case PSI_T_INT:
 167         case PSI_T_ENUM:
 168                 return &ffi_type_sint;
 169         case PSI_T_LONG:
 170                 return &ffi_type_slong;
 171         case PSI_T_FLOAT:
 172                 return &ffi_type_float;
 173         case PSI_T_DOUBLE:
 174                 return &ffi_type_double;
 175 #ifdef HAVE_LONG_DOUBLE
 176         case PSI_T_LONG_DOUBLE:
 177                 return &ffi_type_longdouble;
 178 #endif
 179         case PSI_T_POINTER:
 180         case PSI_T_FUNCTION:
 181                 return &ffi_type_pointer;
 182         }
 183 }
 184 static inline ffi_type *psi_ffi_impl_type(token_t impl_type) {
 185         switch (impl_type) {
 186         case PSI_T_BOOL:
 187                 return &ffi_type_sint8;
 188         case PSI_T_INT:
 189                 return &ffi_type_sint64;
 190         case PSI_T_STRING:
 191                 return &ffi_type_pointer;
 192         case PSI_T_FLOAT:
 193         case PSI_T_DOUBLE:
 194                 return &ffi_type_double;
 195         EMPTY_SWITCH_DEFAULT_CASE();
 196         }
 197         return NULL;
 198 }
 199 static void psi_ffi_struct_type_dtor(void *type) {
 200         ffi_type *strct = type;
 201
 202         if (strct->elements) {
 203                 ffi_type **ptr;
 204
 205                 for (ptr = strct->elements; *ptr; ++ptr) {
 206                         free(*ptr);
 207                 }
 208                 free(strct->elements);
 209         }
 210         free(strct);
 211 }
 212
 213 static size_t psi_ffi_struct_type_pad(ffi_type **els, size_t padding) {
 214         size_t i;
 215
 216         for (i = 0; i < padding; ++i) {
 217                 ffi_type *pad = malloc(sizeof(*pad));
 218
 219                 memcpy(pad, &ffi_type_schar, sizeof(*pad));
 220                 *els++ = pad;
 221         }
 222
 223         return padding;
 224 }
 225
 226 static ffi_type **psi_ffi_struct_type_elements(decl_struct *strct) {
 227         size_t i, argc = strct->args->count, nels = 0, offset = 0, maxalign = 0;
 228         ffi_type **els = calloc(argc + 1, sizeof(*els));
 229
 230         for (i = 0; i < strct->args->count; ++i) {
 231                 decl_arg *darg = strct->args->args[i];
 232                 ffi_type *type = malloc(sizeof(*type));
 233                 size_t padding;
 234
 235                 memcpy(type, psi_ffi_decl_arg_type(darg), sizeof(*type));
 236
 237                 ZEND_ASSERT(type->size == darg->layout->len);
 238
 239                 if (type->alignment > maxalign) {
 240                         maxalign = type->alignment;
 241                 }
 242
 243                 if ((padding = psi_offset_padding(darg->layout->pos - offset, type->alignment))) {
 244                         if (nels + padding + 1 > argc) {
 245                                 argc += padding;
 246                                 els = realloc(els, (argc + 1) * sizeof(*els));
 247                                 els[argc] = NULL;
 248                         }
 249                         psi_ffi_struct_type_pad(&els[nels], padding);
 250                         nels += padding;
 251                         offset += padding;
 252                 }
 253                 ZEND_ASSERT(offset == darg->layout->pos);
 254
 255                 offset = (offset + darg->layout->len + type->alignment - 1) & ~(type->alignment - 1);
 256                 els[nels++] = type;
 257         }
 258
 259         /* apply struct alignment padding */
 260         offset = (offset + maxalign - 1) & ~(maxalign - 1);
 261
 262         ZEND_ASSERT(offset <= strct->size);
 263         if (offset < strct->size) {
 264                 psi_ffi_struct_type_pad(&els[nels], strct->size - offset);
 265         }
 266
 267         return els;
 268 }
 269 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
 270         decl_type *real = real_decl_type(type);
 271
 272         switch (real->type) {
 273         case PSI_T_STRUCT:
 274                 if (!real->real.strct->engine.type) {
 275                         ffi_type *strct = calloc(1, sizeof(ffi_type));
 276
 277                         strct->type = FFI_TYPE_STRUCT;
 278                         strct->size = 0;
 279                         strct->elements = psi_ffi_struct_type_elements(real->real.strct);
 280
 281                         real->real.strct->engine.type = strct;
 282                         real->real.strct->engine.dtor = psi_ffi_struct_type_dtor;
 283                 }
 284
 285                 return real->real.strct->engine.type;
 286
 287         case PSI_T_UNION:
 288                 return psi_ffi_decl_arg_type(real->real.unn->args->args[0]);
 289
 290         default:
 291                 return psi_ffi_token_type(real->type);
 292         }
 293 }
 294 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 295         if (darg->var->pointer_level) {
 296                 return &ffi_type_pointer;
 297         } else {
 298                 return psi_ffi_decl_type(darg->type);
 299         }
 300 }
 301
 302
 303 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 304         ffi_status rc;
 305
 306         if (!L) {
 307                 L = malloc(sizeof(*L));
 308         }
 309         memset(L, 0, sizeof(*L));
 310
 311         L->params[0] = &ffi_type_pointer;
 312         L->params[1] = &ffi_type_pointer;
 313         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 314         ZEND_ASSERT(rc == FFI_OK);
 315
 316         return L;
 317 }
 318
 319 static inline void PSI_LibffiContextFree(PSI_LibffiContext **L) {
 320         if (*L) {
 321                 free(*L);
 322                 *L = NULL;
 323         }
 324 }
 325
 326 static void psi_ffi_init(PSI_Context *C)
 327 {
 328         C->context = PSI_LibffiContextInit(NULL);
 329 }
 330
 331 static void psi_ffi_dtor(PSI_Context *C)
 332 {
 333         if (C->decls) {
 334                 size_t i;
 335
 336                 for (i = 0; i < C->decls->count; ++i) {
 337                         decl *decl = C->decls->list[i];
 338
 339                         if (decl->call.info) {
 340                                 PSI_LibffiCallFree(decl->call.info);
 341                         }
 342                 }
 343
 344         }
 345         if (C->impls) {
 346                 size_t i, j;
 347
 348                 for (i = 0; i < C->impls->count; ++i) {
 349                         impl *impl = C->impls->list[i];
 350
 351                         for (j = 0; j < impl->stmts->let.count; ++j) {
 352                                 let_stmt *let = impl->stmts->let.list[j];
 353
 354                                 if (let->val && let->val->kind == PSI_LET_CALLBACK) {
 355                                         let_callback *cb = let->val->data.callback;
 356
 357                                         if (cb->decl && cb->decl->call.info) {
 358                                                 PSI_LibffiCallFree(cb->decl->call.info);
 359                                         }
 360                                 }
 361                         }
 362                 }
 363         }
 364         PSI_LibffiContextFree((void *) &C->context);
 365 }
 366
 367 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 368 {
 369         size_t c, i, j = 0;
 370         zend_function_entry *zfe;
 371
 372         if (!C->impls) {
 373                 return NULL;
 374         }
 375
 376         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 377         for (i = 0; i < C->impls->count; ++i) {
 378                 zend_function_entry *zf = &zfe[j];
 379                 PSI_LibffiCall *call;
 380                 impl *impl = C->impls->list[i];
 381
 382                 if (!impl->decl) {
 383                         continue;
 384                 }
 385
 386                 if ((call = PSI_LibffiCallAlloc(C, impl->decl))) {
 387                         if (FFI_OK != PSI_LibffiCallInitClosure(C, call, impl)) {
 388                                 PSI_LibffiCallFree(call);
 389                                 continue;
 390                         }
 391                 }
 392
 393                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 394                 zf->num_args = impl->func->args->count;
 395                 zf->handler = call->code;
 396                 zf->arg_info = psi_internal_arginfo(impl);
 397                 ++j;
 398
 399                 for (c = 0; c < impl->stmts->let.count; ++c) {
 400                         let_stmt *let = impl->stmts->let.list[c];
 401
 402                         if (let->val && let->val->kind == PSI_LET_CALLBACK) {
 403                                 let_callback *cb = let->val->data.callback;
 404
 405                                 if ((call = PSI_LibffiCallAlloc(C, cb->decl))) {
 406                                         if (FFI_OK != PSI_LibffiCallInitCallbackClosure(C, call, cb)) {
 407                                                 PSI_LibffiCallFree(call);
 408                                                 continue;
 409                                         }
 410
 411                                         cb->decl->call.sym = call->code;
 412                                 }
 413                         }
 414                 }
 415         }
 416
 417         for (i = 0; i < C->decls->count; ++i) {
 418                 decl *decl = C->decls->list[i];
 419
 420                 if (decl->call.info) {
 421                         continue;
 422                 }
 423
 424                 PSI_LibffiCallAlloc(C, decl);
 425         }
 426
 427         return zfe;
 428 }
 429
 430 static void psi_ffi_call(PSI_Context *C, decl_callinfo *decl_call, impl_vararg *va) {
 431         PSI_LibffiCall *call = decl_call->info;
 432
 433         if (va) {
 434                 ffi_status rc;
 435                 ffi_cif signature;
 436                 size_t i, nfixedargs = decl_call->argc, ntotalargs = nfixedargs + va->args->count;
 437                 void **params = calloc(2 * ntotalargs + 2, sizeof(void *));
 438
 439                 for (i = 0; i < nfixedargs; ++i) {
 440                         params[i] = call->params[i];
 441                         params[i + ntotalargs + 1] = call->params[i + nfixedargs + 1];
 442                 }
 443                 for (i = 0; i < va->args->count; ++i) {
 444                         params[nfixedargs + i] = psi_ffi_impl_type(va->types[i]);
 445                         params[nfixedargs + i + ntotalargs + 1] = &va->values[i];
 446                 }
 447 #ifdef PSI_HAVE_FFI_PREP_CIF_VAR
 448                 rc = ffi_prep_cif_var(&signature, call->signature.abi,
 449                                 nfixedargs, ntotalargs,
 450                                 call->signature.rtype, (ffi_type **) params);
 451 #else
 452                 /* FIXME: test in config.m4; assume we can just call anyway */
 453                 rc = ffi_prep_cif(&signature, call->signature.abi, ntotalargs,
 454                                 call->signature.rtype, (ffi_type **) params);
 455 #endif
 456                 ZEND_ASSERT(FFI_OK == rc);
 457                 ffi_call(&signature, FFI_FN(decl_call->sym), *decl_call->rval, &params[ntotalargs + 1]);
 458                 free(params);
 459         } else {
 460                 ffi_call(&call->signature, FFI_FN(decl_call->sym), *decl_call->rval, decl_call->args);
 461         }
 462 }
 463
 464 static PSI_ContextOps ops = {
 465         psi_ffi_init,
 466         psi_ffi_dtor,
 467         psi_ffi_compile,
 468         psi_ffi_call,
 469 };
 470
 471 PSI_ContextOps *PSI_Libffi(void)
 472 {
 473         return &ops;
 474 }
 475
 476 #endif /* HAVE_LIBFFI */