libffi/src/raw_api.c

   1 /* -----------------------------------------------------------------------
   2    raw_api.c - Copyright (c) 1999, 2008  Red Hat, Inc.
   3
   4    Author: Kresten Krab Thorup <krab@gnu.org>
   5
   6    Permission is hereby granted, free of charge, to any person obtaining
   7    a copy of this software and associated documentation files (the
   8    ``Software''), to deal in the Software without restriction, including
   9    without limitation the rights to use, copy, modify, merge, publish,
  10    distribute, sublicense, and/or sell copies of the Software, and to
  11    permit persons to whom the Software is furnished to do so, subject to
  12    the following conditions:
  13
  14    The above copyright notice and this permission notice shall be included
  15    in all copies or substantial portions of the Software.
  16
  17    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
  18    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20    NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24    DEALINGS IN THE SOFTWARE.
  25    ----------------------------------------------------------------------- */
  26
  27 /* This file defines generic functions for use with the raw api. */
  28
  29 #include <ffi.h>
  30 #include <ffi_common.h>
  31
  32 #if !FFI_NO_RAW_API
  33
  34 size_t
  35 ffi_raw_size (ffi_cif *cif)
  36 {
  37   size_t result = 0;
  38   int i;
  39
  40   ffi_type **at = cif->arg_types;
  41
  42   for (i = cif->nargs-1; i >= 0; i--, at++)
  43     {
  44 #if !FFI_NO_STRUCTS
  45       if ((*at)->type == FFI_TYPE_STRUCT)
  46         result += ALIGN (sizeof (void*), FFI_SIZEOF_ARG);
  47       else
  48 #endif
  49         result += ALIGN ((*at)->size, FFI_SIZEOF_ARG);
  50     }
  51
  52   return result;
  53 }
  54
  55
  56 void
  57 ffi_raw_to_ptrarray (ffi_cif *cif, ffi_raw *raw, void **args)
  58 {
  59   unsigned i;
  60   ffi_type **tp = cif->arg_types;
  61
  62 #if WORDS_BIGENDIAN
  63
  64   for (i = 0; i < cif->nargs; i++, tp++, args++)
  65     {
  66       switch ((*tp)->type)
  67         {
  68         case FFI_TYPE_UINT8:
  69         case FFI_TYPE_SINT8:
  70           *args = (void*) ((char*)(raw++) + FFI_SIZEOF_ARG - 1);
  71           break;
  72
  73         case FFI_TYPE_UINT16:
  74         case FFI_TYPE_SINT16:
  75           *args = (void*) ((char*)(raw++) + FFI_SIZEOF_ARG - 2);
  76           break;
  77
  78 #if FFI_SIZEOF_ARG >= 4
  79         case FFI_TYPE_UINT32:
  80         case FFI_TYPE_SINT32:
  81           *args = (void*) ((char*)(raw++) + FFI_SIZEOF_ARG - 4);
  82           break;
  83 #endif
  84
  85 #if !FFI_NO_STRUCTS
  86         case FFI_TYPE_STRUCT:
  87           *args = (raw++)->ptr;
  88           break;
  89 #endif
  90
  91         case FFI_TYPE_POINTER:
  92           *args = (void*) &(raw++)->ptr;
  93           break;
  94
  95         default:
  96           *args = raw;
  97           raw += ALIGN ((*tp)->size, FFI_SIZEOF_ARG) / FFI_SIZEOF_ARG;
  98         }
  99     }
 100
 101 #else /* WORDS_BIGENDIAN */
 102
 103 #if !PDP
 104
 105   /* then assume little endian */
 106   for (i = 0; i < cif->nargs; i++, tp++, args++)
 107     {
 108 #if !FFI_NO_STRUCTS
 109       if ((*tp)->type == FFI_TYPE_STRUCT)
 110         {
 111           *args = (raw++)->ptr;
 112         }
 113       else
 114 #endif
 115         {
 116           *args = (void*) raw;
 117           raw += ALIGN ((*tp)->size, sizeof (void*)) / sizeof (void*);
 118         }
 119     }
 120
 121 #else
 122 #error "pdp endian not supported"
 123 #endif /* ! PDP */
 124
 125 #endif /* WORDS_BIGENDIAN */
 126 }
 127
 128 void
 129 ffi_ptrarray_to_raw (ffi_cif *cif, void **args, ffi_raw *raw)
 130 {
 131   unsigned i;
 132   ffi_type **tp = cif->arg_types;
 133
 134   for (i = 0; i < cif->nargs; i++, tp++, args++)
 135     {
 136       switch ((*tp)->type)
 137         {
 138         case FFI_TYPE_UINT8:
 139           (raw++)->uint = *(UINT8*) (*args);
 140           break;
 141
 142         case FFI_TYPE_SINT8:
 143           (raw++)->sint = *(SINT8*) (*args);
 144           break;
 145
 146         case FFI_TYPE_UINT16:
 147           (raw++)->uint = *(UINT16*) (*args);
 148           break;
 149
 150         case FFI_TYPE_SINT16:
 151           (raw++)->sint = *(SINT16*) (*args);
 152           break;
 153
 154 #if FFI_SIZEOF_ARG >= 4
 155         case FFI_TYPE_UINT32:
 156           (raw++)->uint = *(UINT32*) (*args);
 157           break;
 158
 159         case FFI_TYPE_SINT32:
 160           (raw++)->sint = *(SINT32*) (*args);
 161           break;
 162 #endif
 163
 164 #if !FFI_NO_STRUCTS
 165         case FFI_TYPE_STRUCT:
 166           (raw++)->ptr = *args;
 167           break;
 168 #endif
 169
 170         case FFI_TYPE_POINTER:
 171           (raw++)->ptr = **(void***) args;
 172           break;
 173
 174         default:
 175           memcpy ((void*) raw->data, (void*)*args, (*tp)->size);
 176           raw += ALIGN ((*tp)->size, FFI_SIZEOF_ARG) / FFI_SIZEOF_ARG;
 177         }
 178     }
 179 }
 180
 181 #if !FFI_NATIVE_RAW_API
 182
 183
 184 /* This is a generic definition of ffi_raw_call, to be used if the
 185  * native system does not provide a machine-specific implementation.
 186  * Having this, allows code to be written for the raw API, without
 187  * the need for system-specific code to handle input in that format;
 188  * these following couple of functions will handle the translation forth
 189  * and back automatically. */
 190
 191 void ffi_raw_call (ffi_cif *cif, void (*fn)(void), void *rvalue, ffi_raw *raw)
 192 {
 193   void **avalue = (void**) alloca (cif->nargs * sizeof (void*));
 194   ffi_raw_to_ptrarray (cif, raw, avalue);
 195   ffi_call (cif, fn, rvalue, avalue);
 196 }
 197
 198 #if FFI_CLOSURES                /* base system provides closures */
 199
 200 static void
 201 ffi_translate_args (ffi_cif *cif, void *rvalue,
 202                     void **avalue, void *user_data)
 203 {
 204   ffi_raw *raw = (ffi_raw*)alloca (ffi_raw_size (cif));
 205   ffi_raw_closure *cl = (ffi_raw_closure*)user_data;
 206
 207   ffi_ptrarray_to_raw (cif, avalue, raw);
 208   (*cl->fun) (cif, rvalue, raw, cl->user_data);
 209 }
 210
 211 ffi_status
 212 ffi_prep_raw_closure_loc (ffi_raw_closure* cl,
 213                           ffi_cif *cif,
 214                           void (*fun)(ffi_cif*,void*,ffi_raw*,void*),
 215                           void *user_data,
 216                           void *codeloc)
 217 {
 218   ffi_status status;
 219
 220   status = ffi_prep_closure_loc ((ffi_closure*) cl,
 221                                  cif,
 222                                  &ffi_translate_args,
 223                                  codeloc,
 224                                  codeloc);
 225   if (status == FFI_OK)
 226     {
 227       cl->fun       = fun;
 228       cl->user_data = user_data;
 229     }
 230
 231   return status;
 232 }
 233
 234 #endif /* FFI_CLOSURES */
 235 #endif /* !FFI_NATIVE_RAW_API */
 236
 237 #if FFI_CLOSURES
 238
 239 /* Again, here is the generic version of ffi_prep_raw_closure, which
 240  * will install an intermediate "hub" for translation of arguments from
 241  * the pointer-array format, to the raw format */
 242
 243 ffi_status
 244 ffi_prep_raw_closure (ffi_raw_closure* cl,
 245                       ffi_cif *cif,
 246                       void (*fun)(ffi_cif*,void*,ffi_raw*,void*),
 247                       void *user_data)
 248 {
 249   return ffi_prep_raw_closure_loc (cl, cif, fun, user_data, cl);
 250 }
 251
 252 #endif /* FFI_CLOSURES */
 253
 254 #endif /* !FFI_NO_RAW_API */