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         }
  95 }
  96 static inline ffi_type *psi_ffi_impl_type(token_t impl_type) {
  97         switch (impl_type) {
  98         case PSI_T_BOOL:
  99                 return &ffi_type_sint8;
 100         case PSI_T_INT:
 101                 return &ffi_type_sint64;
 102         case PSI_T_STRING:
 103                 return &ffi_type_pointer;
 104         case PSI_T_FLOAT:
 105         case PSI_T_DOUBLE:
 106                 return &ffi_type_double;
 107         EMPTY_SWITCH_DEFAULT_CASE();
 108         }
 109 }
 110 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
 111         return psi_ffi_token_type(real_decl_type(type)->type);
 112 }
 113 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 114         if (darg->var->pointer_level) {
 115                 return &ffi_type_pointer;
 116         } else {
 117                 return psi_ffi_decl_type(darg->type);
 118         }
 119 }
 120
 121 typedef struct PSI_LibffiContext {
 122         ffi_cif signature;
 123         ffi_type *params[2];
 124 } PSI_LibffiContext;
 125
 126 typedef struct PSI_LibffiCall {
 127         void *code;
 128         ffi_closure *closure;
 129         ffi_cif signature;
 130         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 131 } PSI_LibffiCall;
 132
 133 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 134         int rc;
 135         size_t i, c = decl->args ? decl->args->count : 0;
 136         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 137
 138         for (i = 0; i < c; ++i) {
 139                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 140         }
 141         call->params[c] = NULL;
 142
 143         decl->call.info = call;
 144         decl->call.rval = decl->func->ptr;
 145         decl->call.argc = c;
 146         decl->call.args = (void **) &call->params[c+1];
 147
 148         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 149                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 150         ZEND_ASSERT(FFI_OK == rc);
 151
 152         return call;
 153 }
 154
 155 static inline void PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 156         PSI_LibffiContext *context = C->context;
 157         int rc;
 158
 159         call->closure = psi_ffi_closure_alloc(sizeof(ffi_closure), &call->code);
 160         ZEND_ASSERT(call->closure != NULL);
 161
 162 #if PSI_HAVE_FFI_PREP_CLOSURE_LOC
 163         rc = ffi_prep_closure_loc(
 164                         call->closure,
 165                         &context->signature,
 166                         psi_ffi_handler,
 167                         impl,
 168                         call->code);
 169
 170 #elif PSI_HAVE_FFI_PREP_CLOSURE
 171         rc = ffi_prep_closure(call->code, &context->signature, psi_ffi_handler, impl);
 172 #else
 173 # error "Neither ffi_prep_closure() nor ffi_prep_closure_loc() available"
 174 #endif
 175         ZEND_ASSERT(FFI_OK == rc);
 176 }
 177
 178 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 179         if (call->closure) {
 180                 psi_ffi_closure_free(call->closure);
 181         }
 182         free(call);
 183 }
 184
 185 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 186         ffi_status rc;
 187
 188         if (!L) {
 189                 L = malloc(sizeof(*L));
 190         }
 191         memset(L, 0, sizeof(*L));
 192
 193         L->params[0] = &ffi_type_pointer;
 194         L->params[1] = &ffi_type_pointer;
 195         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 196         ZEND_ASSERT(rc == FFI_OK);
 197
 198         return L;
 199 }
 200
 201 static void psi_ffi_handler(ffi_cif *_sig, void *_result, void **_args, void *_data)
 202 {
 203         psi_call(*(zend_execute_data **)_args[0], *(zval **)_args[1], _data);
 204 }
 205
 206 static void psi_ffi_init(PSI_Context *C)
 207 {
 208         C->context = PSI_LibffiContextInit(NULL);
 209 }
 210
 211 static void psi_ffi_dtor(PSI_Context *C)
 212 {
 213         if (C->decls) {
 214                 size_t i;
 215
 216                 for (i = 0; i < C->decls->count; ++i) {
 217                         decl *decl = C->decls->list[i];
 218
 219                         if (decl->call.info) {
 220                                 PSI_LibffiCallFree(decl->call.info);
 221                         }
 222                 }
 223         }
 224         free(C->context);
 225 }
 226
 227 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 228 {
 229         size_t i, j = 0;
 230         zend_function_entry *zfe;
 231
 232         if (!C->impls) {
 233                 return NULL;
 234         }
 235
 236         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 237         for (i = 0; i < C->impls->count; ++i) {
 238                 zend_function_entry *zf = &zfe[j];
 239                 PSI_LibffiCall *call;
 240                 impl *impl = C->impls->list[i];
 241
 242                 if (!impl->decl) {
 243                         continue;
 244                 }
 245
 246                 call = PSI_LibffiCallAlloc(C, impl->decl);
 247                 PSI_LibffiCallInitClosure(C, call, impl);
 248
 249                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 250                 zf->num_args = impl->func->args->count;
 251                 zf->handler = call->code;
 252                 zf->arg_info = psi_internal_arginfo(impl);
 253                 ++j;
 254         }
 255
 256         for (i = 0; i < C->decls->count; ++i) {
 257                 decl *decl = C->decls->list[i];
 258
 259                 if (decl->impl) {
 260                         continue;
 261                 }
 262
 263                 PSI_LibffiCallAlloc(C, decl);
 264         }
 265
 266         return zfe;
 267 }
 268
 269 static void psi_ffi_call(PSI_Context *C, decl_callinfo *decl_call, impl_vararg *va) {
 270         PSI_LibffiCall *call = decl_call->info;
 271
 272         if (va) {
 273                 ffi_status rc;
 274                 ffi_cif signature;
 275                 size_t i, nfixedargs = decl_call->argc, ntotalargs = nfixedargs + va->args->count;
 276                 void **params = calloc(2 * ntotalargs + 2, sizeof(void *));
 277
 278                 for (i = 0; i < nfixedargs; ++i) {
 279                         params[i] = call->params[i];
 280                         params[i + ntotalargs + 1] = call->params[i + nfixedargs + 1];
 281                 }
 282                 for (i = 0; i < va->args->count; ++i) {
 283                         params[nfixedargs + i] = psi_ffi_impl_type(va->types[i]);
 284                         params[nfixedargs + i + ntotalargs + 1] = &va->values[i];
 285                 }
 286 #ifdef PSI_HAVE_FFI_PREP_CIF_VAR
 287                 rc = ffi_prep_cif_var(&signature, call->signature.abi,
 288                                 nfixedargs, ntotalargs,
 289                                 call->signature.rtype, (ffi_type **) params);
 290 #else
 291                 /* FIXME: test in config.m4; assume we can just call anyway */
 292                 rc = ffi_prep_cif(&signature, call->signature.abi, ntotalargs,
 293                                 call->signature.rtype, (ffi_type **) params);
 294 #endif
 295                 ZEND_ASSERT(FFI_OK == rc);
 296                 ffi_call(&signature, FFI_FN(decl_call->sym), decl_call->rval, &params[ntotalargs + 1]);
 297                 free(params);
 298         } else {
 299                 ffi_call(&call->signature, FFI_FN(decl_call->sym), decl_call->rval, decl_call->args);
 300         }
 301 }
 302
 303 static PSI_ContextOps ops = {
 304         psi_ffi_init,
 305         psi_ffi_dtor,
 306         psi_ffi_compile,
 307         psi_ffi_call,
 308 };
 309
 310 PSI_ContextOps *PSI_Libffi(void)
 311 {
 312         return &ops;
 313 }
 314
 315 #endif /* HAVE_LIBFFI */