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
  12 #undef PACKAGE
  13 #undef PACKAGE_BUGREPORT
  14 #undef PACKAGE_NAME
  15 #undef PACKAGE_STRING
  16 #undef PACKAGE_TARNAME
  17 #undef PACKAGE_VERSION
  18
  19 #include <ffi.h>
  20
  21 #ifndef PSI_HAVE_FFI_CLOSURE_ALLOC
  22 # if HAVE_UNISTD_H
  23 #  include <unistd.h>
  24 # endif
  25 # if HAVE_SYS_MMAN_H
  26 #  include <sys/mman.h>
  27 #  ifndef MAP_ANONYMOUS
  28 #   define MAP_ANONYMOUS MAP_ANON
  29 #  endif
  30 # endif
  31 #endif
  32
  33 static void *psi_ffi_closure_alloc(size_t s, void **code)
  34 {
  35 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  36         return ffi_closure_alloc(s, code);
  37 #elif HAVE_MMAP
  38         *code = mmap(NULL, s, PROT_EXEC|PROT_WRITE|PROT_READ,
  39                         MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  40         if (MAP_FAILED == *code) {
  41                 return NULL;
  42         }
  43         return *code;
  44 #else
  45         return NULL;
  46 #endif
  47 }
  48
  49 static void psi_ffi_closure_free(void *c)
  50 {
  51 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  52         ffi_closure_free(c);
  53 #elif HAVE_MMAP
  54         munmap(c, sizeof(ffi_closure));
  55 #endif
  56 }
  57
  58 static void psi_ffi_handler(ffi_cif *signature, void *_result, void **_args, void *_data);
  59
  60 static inline ffi_abi psi_ffi_abi(const char *convention) {
  61         return FFI_DEFAULT_ABI;
  62 }
  63 static inline ffi_type *psi_ffi_token_type(token_t t) {
  64         switch (t) {
  65         default:
  66                 ZEND_ASSERT(0);
  67                 /* no break */
  68         case PSI_T_VOID:
  69                 return &ffi_type_void;
  70         case PSI_T_INT8:
  71                 return &ffi_type_sint8;
  72         case PSI_T_UINT8:
  73                 return &ffi_type_uint8;
  74         case PSI_T_INT16:
  75                 return &ffi_type_sint16;
  76         case PSI_T_UINT16:
  77                 return &ffi_type_uint16;
  78         case PSI_T_INT32:
  79                 return &ffi_type_sint32;
  80         case PSI_T_UINT32:
  81                 return &ffi_type_uint32;
  82         case PSI_T_INT64:
  83                 return &ffi_type_sint64;
  84         case PSI_T_UINT64:
  85                 return &ffi_type_uint64;
  86         case PSI_T_BOOL:
  87                 return &ffi_type_uchar;
  88         case PSI_T_INT:
  89                 return &ffi_type_sint;
  90         case PSI_T_FLOAT:
  91                 return &ffi_type_float;
  92         case PSI_T_DOUBLE:
  93                 return &ffi_type_double;
  94         case PSI_T_POINTER:
  95                 return &ffi_type_pointer;
  96         }
  97 }
  98 static inline ffi_type *psi_ffi_impl_type(token_t impl_type) {
  99         switch (impl_type) {
 100         case PSI_T_BOOL:
 101                 return &ffi_type_sint8;
 102         case PSI_T_INT:
 103                 return &ffi_type_sint64;
 104         case PSI_T_STRING:
 105                 return &ffi_type_pointer;
 106         case PSI_T_FLOAT:
 107         case PSI_T_DOUBLE:
 108                 return &ffi_type_double;
 109         EMPTY_SWITCH_DEFAULT_CASE();
 110         }
 111 }
 112 static void psi_ffi_struct_type_dtor(void *type) {
 113         ffi_type *strct = type;
 114
 115         if (strct->elements) {
 116                 free(strct->elements);
 117         }
 118         free(strct);
 119 }
 120 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg);
 121 static ffi_type **psi_ffi_struct_type_elements(decl_struct *strct) {
 122         ffi_type **els = calloc(strct->args->count + 1, sizeof(*els));
 123         size_t i;
 124
 125         for (i = 0; i < strct->args->count; ++i) {
 126                 els[i] = psi_ffi_decl_arg_type(strct->args->args[i]);
 127         }
 128         els[i] = NULL;
 129
 130         return els;
 131 }
 132 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
 133         decl_type *real = real_decl_type(type);
 134
 135         if (real->type == PSI_T_STRUCT) {
 136                 if (!real->strct->engine.type) {
 137                         ffi_type *strct = calloc(1, sizeof(ffi_type));
 138
 139                         strct->type = FFI_TYPE_STRUCT;
 140                         strct->size = real->strct->size;
 141                         strct->alignment = 0;
 142                         strct->elements = psi_ffi_struct_type_elements(real->strct);
 143
 144                         real->strct->engine.type = strct;
 145                         real->strct->engine.dtor = psi_ffi_struct_type_dtor;
 146                 }
 147
 148                 return real->strct->engine.type;
 149         }
 150         return psi_ffi_token_type(real->type);
 151 }
 152 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 153         if (darg->var->pointer_level) {
 154                 return &ffi_type_pointer;
 155         } else {
 156                 return psi_ffi_decl_type(darg->type);
 157         }
 158 }
 159
 160 typedef struct PSI_LibffiContext {
 161         ffi_cif signature;
 162         ffi_type *params[2];
 163 } PSI_LibffiContext;
 164
 165 typedef struct PSI_LibffiCall {
 166         void *code;
 167         ffi_closure *closure;
 168         ffi_cif signature;
 169         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 170 } PSI_LibffiCall;
 171
 172 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 173         int rc;
 174         size_t i, c = decl->args ? decl->args->count : 0;
 175         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 176
 177         for (i = 0; i < c; ++i) {
 178                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 179         }
 180         call->params[c] = NULL;
 181
 182         decl->call.info = call;
 183         decl->call.rval = decl->func->ptr;
 184         decl->call.argc = c;
 185         decl->call.args = (void **) &call->params[c+1];
 186
 187         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 188                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 189         ZEND_ASSERT(FFI_OK == rc);
 190
 191         return call;
 192 }
 193
 194 static inline void PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 195         PSI_LibffiContext *context = C->context;
 196         int rc;
 197
 198         call->closure = psi_ffi_closure_alloc(sizeof(ffi_closure), &call->code);
 199         ZEND_ASSERT(call->closure != NULL);
 200
 201 #if PSI_HAVE_FFI_PREP_CLOSURE_LOC
 202         rc = ffi_prep_closure_loc(
 203                         call->closure,
 204                         &context->signature,
 205                         psi_ffi_handler,
 206                         impl,
 207                         call->code);
 208
 209 #elif PSI_HAVE_FFI_PREP_CLOSURE
 210         rc = ffi_prep_closure(call->code, &context->signature, psi_ffi_handler, impl);
 211 #else
 212 # error "Neither ffi_prep_closure() nor ffi_prep_closure_loc() available"
 213 #endif
 214         ZEND_ASSERT(FFI_OK == rc);
 215 }
 216
 217 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 218         if (call->closure) {
 219                 psi_ffi_closure_free(call->closure);
 220         }
 221         free(call);
 222 }
 223
 224 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 225         ffi_status rc;
 226
 227         if (!L) {
 228                 L = malloc(sizeof(*L));
 229         }
 230         memset(L, 0, sizeof(*L));
 231
 232         L->params[0] = &ffi_type_pointer;
 233         L->params[1] = &ffi_type_pointer;
 234         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 235         ZEND_ASSERT(rc == FFI_OK);
 236
 237         return L;
 238 }
 239
 240 static void psi_ffi_handler(ffi_cif *_sig, void *_result, void **_args, void *_data)
 241 {
 242         psi_call(*(zend_execute_data **)_args[0], *(zval **)_args[1], _data);
 243 }
 244
 245 static void psi_ffi_init(PSI_Context *C)
 246 {
 247         C->context = PSI_LibffiContextInit(NULL);
 248 }
 249
 250 static void psi_ffi_dtor(PSI_Context *C)
 251 {
 252         if (C->decls) {
 253                 size_t i;
 254
 255                 for (i = 0; i < C->decls->count; ++i) {
 256                         decl *decl = C->decls->list[i];
 257
 258                         if (decl->call.info) {
 259                                 PSI_LibffiCallFree(decl->call.info);
 260                         }
 261                 }
 262         }
 263         free(C->context);
 264 }
 265
 266 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 267 {
 268         size_t i, j = 0;
 269         zend_function_entry *zfe;
 270
 271         if (!C->impls) {
 272                 return NULL;
 273         }
 274
 275         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 276         for (i = 0; i < C->impls->count; ++i) {
 277                 zend_function_entry *zf = &zfe[j];
 278                 PSI_LibffiCall *call;
 279                 impl *impl = C->impls->list[i];
 280
 281                 if (!impl->decl) {
 282                         continue;
 283                 }
 284
 285                 call = PSI_LibffiCallAlloc(C, impl->decl);
 286                 PSI_LibffiCallInitClosure(C, call, impl);
 287
 288                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 289                 zf->num_args = impl->func->args->count;
 290                 zf->handler = call->code;
 291                 zf->arg_info = psi_internal_arginfo(impl);
 292                 ++j;
 293         }
 294
 295         for (i = 0; i < C->decls->count; ++i) {
 296                 decl *decl = C->decls->list[i];
 297
 298                 if (decl->impl) {
 299                         continue;
 300                 }
 301
 302                 PSI_LibffiCallAlloc(C, decl);
 303         }
 304
 305         return zfe;
 306 }
 307
 308 static void psi_ffi_call(PSI_Context *C, decl_callinfo *decl_call, impl_vararg *va) {
 309         PSI_LibffiCall *call = decl_call->info;
 310
 311         if (va) {
 312                 ffi_status rc;
 313                 ffi_cif signature;
 314                 size_t i, nfixedargs = decl_call->argc, ntotalargs = nfixedargs + va->args->count;
 315                 void **params = calloc(2 * ntotalargs + 2, sizeof(void *));
 316
 317                 for (i = 0; i < nfixedargs; ++i) {
 318                         params[i] = call->params[i];
 319                         params[i + ntotalargs + 1] = call->params[i + nfixedargs + 1];
 320                 }
 321                 for (i = 0; i < va->args->count; ++i) {
 322                         params[nfixedargs + i] = psi_ffi_impl_type(va->types[i]);
 323                         params[nfixedargs + i + ntotalargs + 1] = &va->values[i];
 324                 }
 325 #ifdef PSI_HAVE_FFI_PREP_CIF_VAR
 326                 rc = ffi_prep_cif_var(&signature, call->signature.abi,
 327                                 nfixedargs, ntotalargs,
 328                                 call->signature.rtype, (ffi_type **) params);
 329 #else
 330                 /* FIXME: test in config.m4; assume we can just call anyway */
 331                 rc = ffi_prep_cif(&signature, call->signature.abi, ntotalargs,
 332                                 call->signature.rtype, (ffi_type **) params);
 333 #endif
 334                 ZEND_ASSERT(FFI_OK == rc);
 335                 ffi_call(&signature, FFI_FN(decl_call->sym), decl_call->rval, &params[ntotalargs + 1]);
 336                 free(params);
 337         } else {
 338                 ffi_call(&call->signature, FFI_FN(decl_call->sym), decl_call->rval, decl_call->args);
 339         }
 340 }
 341
 342 static PSI_ContextOps ops = {
 343         psi_ffi_init,
 344         psi_ffi_dtor,
 345         psi_ffi_compile,
 346         psi_ffi_call,
 347 };
 348
 349 PSI_ContextOps *PSI_Libffi(void)
 350 {
 351         return &ops;
 352 }
 353
 354 #endif /* HAVE_LIBFFI */