git.m6w6.name Git - m6w6/ext-psi/blob - src/libffi.c

   1 #include "php.h"
   2 #include "php_psi.h"
   3 #include "libffi.h"
   4
   5 #undef PACKAGE
   6 #undef PACKAGE_BUGREPORT
   7 #undef PACKAGE_NAME
   8 #undef PACKAGE_STRING
   9 #undef PACKAGE_TARNAME
  10 #undef PACKAGE_VERSION
  11
  12 #include <ffi.h>
  13
  14 #ifndef PSI_HAVE_FFI_CLOSURE_ALLOC
  15 # if HAVE_UNISTD_H
  16 #  include <unistd.h>
  17 # endif
  18 # if HAVE_SYS_MMAN_H
  19 #  include <sys/mman.h>
  20 #  ifndef MAP_ANONYMOUS
  21 #   define MAP_ANONYMOUS MAP_ANON
  22 #  endif
  23 # endif
  24 #endif
  25
  26 static void *psi_ffi_closure_alloc(size_t s, void **code)
  27 {
  28 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  29         return ffi_closure_alloc(s, code);
  30 #elif HAVE_MMAP
  31         *code = mmap(NULL, s, PROT_EXEC|PROT_WRITE|PROT_READ,
  32                         MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
  33         if (MAP_FAILED == *code) {
  34                 return NULL;
  35         }
  36         return *code;
  37 #else
  38         return NULL;
  39 #endif
  40 }
  41
  42 static void psi_ffi_closure_free(void *c)
  43 {
  44 #ifdef PSI_HAVE_FFI_CLOSURE_ALLOC
  45         ffi_closure_free(c);
  46 #elif HAVE_MMAP
  47         munmap(c, sizeof(ffi_closure));
  48 #endif
  49 }
  50
  51 static void psi_ffi_handler(ffi_cif *signature, void *_result, void **_args, void *_data);
  52
  53 static inline ffi_abi psi_ffi_abi(const char *convention) {
  54         return FFI_DEFAULT_ABI;
  55 }
  56 static inline ffi_type *psi_ffi_token_type(token_t t) {
  57         switch (t) {
  58         default:
  59                 ZEND_ASSERT(0);
  60                 /* no break */
  61         case PSI_T_VOID:
  62                 return &ffi_type_void;
  63         case PSI_T_INT8:
  64                 return &ffi_type_sint8;
  65         case PSI_T_UINT8:
  66                 return &ffi_type_uint8;
  67         case PSI_T_INT16:
  68                 return &ffi_type_sint16;
  69         case PSI_T_UINT16:
  70                 return &ffi_type_uint16;
  71         case PSI_T_INT32:
  72                 return &ffi_type_sint32;
  73         case PSI_T_UINT32:
  74                 return &ffi_type_uint32;
  75         case PSI_T_INT64:
  76                 return &ffi_type_sint64;
  77         case PSI_T_UINT64:
  78                 return &ffi_type_uint64;
  79         case PSI_T_BOOL:
  80                 return &ffi_type_uchar;
  81         case PSI_T_INT:
  82                 return &ffi_type_sint;
  83         case PSI_T_FLOAT:
  84                 return &ffi_type_float;
  85         case PSI_T_DOUBLE:
  86                 return &ffi_type_double;
  87         }
  88 }
  89 static inline ffi_type *psi_ffi_decl_type(decl_type *type) {
  90         return psi_ffi_token_type(real_decl_type(type)->type);
  91 }
  92 static inline ffi_type *psi_ffi_decl_arg_type(decl_arg *darg) {
  93         if (darg->var->pointer_level) {
  94                 return &ffi_type_pointer;
  95         } else {
  96                 return psi_ffi_decl_type(darg->type);
  97         }
  98 }
  99
 100 typedef struct PSI_LibffiContext {
 101         ffi_cif signature;
 102         ffi_type *params[2];
 103 } PSI_LibffiContext;
 104
 105 typedef struct PSI_LibffiCall {
 106         void *code;
 107         ffi_closure *closure;
 108         ffi_cif signature;
 109         void *params[1]; /* [type1, type2, NULL, arg1, arg2] ... */
 110 } PSI_LibffiCall;
 111
 112 static inline PSI_LibffiCall *PSI_LibffiCallAlloc(PSI_Context *C, decl *decl) {
 113         int rc;
 114         size_t i, c = decl->args ? decl->args->count : 0;
 115         PSI_LibffiCall *call = calloc(1, sizeof(*call) + 2 * c * sizeof(void *));
 116
 117         for (i = 0; i < c; ++i) {
 118                 call->params[i] = psi_ffi_decl_arg_type(decl->args->args[i]);
 119         }
 120         call->params[c] = NULL;
 121
 122         decl->call.info = call;
 123         decl->call.args = (void **) &call->params[c+1];
 124
 125         rc = ffi_prep_cif(&call->signature, psi_ffi_abi(decl->abi->convention),
 126                         c, psi_ffi_decl_arg_type(decl->func), (ffi_type **) call->params);
 127         ZEND_ASSERT(FFI_OK == rc);
 128
 129         return call;
 130 }
 131
 132 static inline void PSI_LibffiCallInitClosure(PSI_Context *C, PSI_LibffiCall *call, impl *impl) {
 133         PSI_LibffiContext *context = C->context;
 134         int rc;
 135
 136         call->closure = psi_ffi_closure_alloc(sizeof(ffi_closure), &call->code);
 137         ZEND_ASSERT(call->closure != NULL);
 138
 139 #if PSI_HAVE_FFI_PREP_CLOSURE_LOC
 140         rc = ffi_prep_closure_loc(
 141                         call->closure,
 142                         &context->signature,
 143                         psi_ffi_handler,
 144                         impl,
 145                         call->code);
 146
 147 #elif PSI_HAVE_FFI_PREP_CLOSURE
 148         rc = ffi_prep_closure(data->code, &context->signature, psi_ffi_handler, data);
 149 #else
 150 # error "Neither ffi_prep_closure() nor ffi_prep_closure_loc() available"
 151 #endif
 152         ZEND_ASSERT(FFI_OK == rc);
 153 }
 154
 155 static inline void PSI_LibffiCallFree(PSI_LibffiCall *call) {
 156         if (call->closure) {
 157                 psi_ffi_closure_free(call->closure);
 158         }
 159         free(call);
 160 }
 161
 162 static inline PSI_LibffiContext *PSI_LibffiContextInit(PSI_LibffiContext *L) {
 163         ffi_status rc;
 164
 165         if (!L) {
 166                 L = malloc(sizeof(*L));
 167         }
 168         memset(L, 0, sizeof(*L));
 169
 170         L->params[0] = &ffi_type_pointer;
 171         L->params[1] = &ffi_type_pointer;
 172         rc = ffi_prep_cif(&L->signature, FFI_DEFAULT_ABI, 2, &ffi_type_void, L->params);
 173         ZEND_ASSERT(rc == FFI_OK);
 174
 175         return L;
 176 }
 177
 178 static void psi_ffi_handler(ffi_cif *_sig, void *_result, void **_args, void *_data)
 179 {
 180         psi_call(*(zend_execute_data **)_args[0], *(zval **)_args[1], _data);
 181 }
 182
 183 static void psi_ffi_init(PSI_Context *C)
 184 {
 185         C->context = PSI_LibffiContextInit(NULL);
 186 }
 187
 188 static void psi_ffi_dtor(PSI_Context *C) {
 189         size_t i;
 190
 191         for (i = 0; i < C->decls->count; ++i) {
 192                 decl *decl = C->decls->list[i];
 193
 194                 if (decl->call.info) {
 195                         PSI_LibffiCallFree(decl->call.info);
 196                 }
 197         }
 198         free(C->context);
 199 }
 200
 201 static zend_function_entry *psi_ffi_compile(PSI_Context *C)
 202 {
 203         size_t i, j = 0;
 204         zend_function_entry *zfe;
 205
 206         if (!C->impls) {
 207                 return NULL;
 208         }
 209
 210         zfe = calloc(C->impls->count + 1, sizeof(*zfe));
 211         for (i = 0; i < C->impls->count; ++i) {
 212                 zend_function_entry *zf = &zfe[j];
 213                 PSI_LibffiCall *call;
 214                 impl *impl = C->impls->list[i];
 215
 216                 if (!impl->decl) {
 217                         continue;
 218                 }
 219
 220                 call = PSI_LibffiCallAlloc(C, impl->decl);
 221                 PSI_LibffiCallInitClosure(C, call, impl);
 222
 223                 zf->fname = impl->func->name + (impl->func->name[0] == '\\');
 224                 zf->num_args = impl->func->args->count;
 225                 zf->handler = call->code;
 226                 zf->arg_info = psi_internal_arginfo(impl);
 227                 ++j;
 228         }
 229
 230         for (i = 0; i < C->decls->count; ++i) {
 231                 decl *decl = C->decls->list[i];
 232
 233                 if (decl->impl) {
 234                         continue;
 235                 }
 236
 237                 PSI_LibffiCallAlloc(C, decl);
 238         }
 239
 240         return zfe;
 241 }
 242
 243 static void psi_ffi_call(PSI_Context *C, impl_val *ret_val, decl *decl) {
 244         PSI_LibffiCall *call = decl->call.info;
 245
 246         ffi_call(&call->signature, FFI_FN(decl->call.sym), ret_val, decl->call.args);
 247 }
 248
 249 static PSI_ContextOps ops = {
 250         psi_ffi_init,
 251         psi_ffi_dtor,
 252         psi_ffi_compile,
 253         psi_ffi_call,
 254 };
 255
 256 PSI_ContextOps *PSI_Libffi(void)
 257 {
 258         return &ops;
 259 }