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_decl_type(decl_type *type) {
  97         return psi_ffi_token_type(real_decl_type(type)->type);
  98 }
  99 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
 100         if (darg->var->pointer_level) {
 101                 return &ffi_type_pointer;
 102         } else {
 103                 return psi_ffi_decl_type(darg->type);
 104         }
 105 }
 106
 107 typedef struct PSI_LibffiContext {
 108         ffi_cif signature;
 109         ffi_type *params[2];
 110 } PSI_LibffiContext;
 111
 112 typedef struct PSI_LibffiCall {
 113         void *code;
 114         ffi_closure *closure;
 115         ffi_cif signature;
 116         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 117 } PSI_LibffiCall;
 118
 119 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 120         int rc;
 121         size_t i, c = decl->args ? decl->args->count : 0;
 122         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 123
 124         for (i = 0; i < c; ++i) {
 125                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 126         }
 127         call->params[c] = NULL;
 128
 129         decl->call.info = call;
 130         decl->call.args = (void **) &call->params[c+1];
 131
 132         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 133                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 134         ZEND_ASSERT(FFI_OK == rc);
 135
 136         return call;
 137 }
 138
 139 static inline void PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 140         PSI_LibffiContext *context = C->context;
 141         int rc;
 142
 143         call->closure = psi_ffi_closure_alloc(sizeof(ffi_closure), &call->code);
 144         ZEND_ASSERT(call->closure != NULL);
 145
 146 #if PSI_HAVE_FFI_PREP_CLOSURE_LOC
 147         rc = ffi_prep_closure_loc(
 148                         call->closure,
 149                         &context->signature,
 150                         psi_ffi_handler,
 151                         impl,
 152                         call->code);
 153
 154 #elif PSI_HAVE_FFI_PREP_CLOSURE
 155         rc = ffi_prep_closure(call->code, &context->signature, psi_ffi_handler, impl);
 156 #else
 157 # error "Neither ffi_prep_closure() nor ffi_prep_closure_loc() available"
 158 #endif
 159         ZEND_ASSERT(FFI_OK == rc);
 160 }
 161
 162 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 163         if (call->closure) {
 164                 psi_ffi_closure_free(call->closure);
 165         }
 166         free(call);
 167 }
 168
 169 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 170         ffi_status rc;
 171
 172         if (!L) {
 173                 L = malloc(sizeof(*L));
 174         }
 175         memset(L, 0, sizeof(*L));
 176
 177         L->params[0] = &ffi_type_pointer;
 178         L->params[1] = &ffi_type_pointer;
 179         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 180         ZEND_ASSERT(rc == FFI_OK);
 181
 182         return L;
 183 }
 184
 185 static void psi_ffi_handler(ffi_cif *_sig, void *_result, void **_args, void *_data)
 186 {
 187         psi_call(*(zend_execute_data **)_args[0], *(zval **)_args[1], _data);
 188 }
 189
 190 static void psi_ffi_init(PSI_Context *C)
 191 {
 192         C->context = PSI_LibffiContextInit(NULL);
 193 }
 194
 195 static void psi_ffi_dtor(PSI_Context *C)
 196 {
 197         if (C->decls) {
 198                 size_t i;
 199
 200                 for (i = 0; i < C->decls->count; ++i) {
 201                         decl *decl = C->decls->list[i];
 202
 203                         if (decl->call.info) {
 204                                 PSI_LibffiCallFree(decl->call.info);
 205                         }
 206                 }
 207         }
 208         free(C->context);
 209 }
 210
 211 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 212 {
 213         size_t i, j = 0;
 214         zend_function_entry *zfe;
 215
 216         if (!C->impls) {
 217                 return NULL;
 218         }
 219
 220         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 221         for (i = 0; i < C->impls->count; ++i) {
 222                 zend_function_entry *zf = &zfe[j];
 223                 PSI_LibffiCall *call;
 224                 impl *impl = C->impls->list[i];
 225
 226                 if (!impl->decl) {
 227                         continue;
 228                 }
 229
 230                 call = PSI_LibffiCallAlloc(C, impl->decl);
 231                 PSI_LibffiCallInitClosure(C, call, impl);
 232
 233                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 234                 zf->num_args = impl->func->args->count;
 235                 zf->handler = call->code;
 236                 zf->arg_info = psi_internal_arginfo(impl);
 237                 ++j;
 238         }
 239
 240         for (i = 0; i < C->decls->count; ++i) {
 241                 decl *decl = C->decls->list[i];
 242
 243                 if (decl->impl) {
 244                         continue;
 245                 }
 246
 247                 PSI_LibffiCallAlloc(C, decl);
 248         }
 249
 250         return zfe;
 251 }
 252
 253 static void psi_ffi_call(PSI_Context *C, impl_val *ret_val, decl *decl) {
 254         PSI_LibffiCall *call = decl->call.info;
 255
 256         ffi_call(&call->signature, FFI_FN(decl->call.sym), ret_val, decl->call.args);
 257 }
 258
 259 static PSI_ContextOps ops = {
 260         psi_ffi_init,
 261         psi_ffi_dtor,
 262         psi_ffi_compile,
 263         psi_ffi_call,
 264 };
 265
 266 PSI_ContextOps *PSI_Libffi(void)
 267 {
 268         return &ops;
 269 }
 270
 271 #endif /* HAVE_LIBFFI */