src/dll_ffi.c

   1 /*
   2  * Copyright (C) 2003, 2004, 2005, 2006, 2007
   3  * Robert Lougher <rob@lougher.org.uk>.
   4  *
   5  * This file is part of JamVM.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2,
  10  * or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 /* Must be included first to get configure options */
  23 #include "jam.h"
  24
  25 #ifdef USE_FFI
  26 #include <ffi.h>
  27 #include <stdio.h>
  28 #include "sig.h"
  29
  30 ffi_type *sig2ffi(char sig) {
  31     ffi_type *type;
  32
  33     switch(sig) {
  34         case 'V':
  35             type = &ffi_type_void;
  36             break;
  37         case 'D':
  38             type = &ffi_type_double;
  39             break;
  40         case 'J':
  41             type = &ffi_type_sint64;
  42             break;
  43         case 'F':
  44             type = &ffi_type_float;
  45             break;
  46         default:
  47             type = &ffi_type_pointer;
  48             break;
  49     }
  50
  51     return type;
  52 }
  53
  54 int nativeExtraArg(MethodBlock *mb) {
  55     char *sig = mb->type;
  56     int count = 2;
  57
  58     SCAN_SIG(sig, count++, count++);
  59
  60     return count;
  61 }
  62
  63 #define DOUBLE                    \
  64     *types_pntr++ = sig2ffi(*sig);\
  65     *values_pntr++ = opntr;       \
  66     opntr += 2
  67
  68 #define SINGLE                    \
  69     *types_pntr++ = sig2ffi(*sig);\
  70     *values_pntr++ = opntr++
  71
  72 uintptr_t *callJNIMethod(void *env, Class *class, char *sig, int num_args, uintptr_t *ostack,
  73                          unsigned char *func) {
  74     ffi_cif cif;
  75     void *values[num_args];
  76     ffi_type *types[num_args];
  77     uintptr_t *opntr = ostack;
  78     void **values_pntr = &values[2];
  79     ffi_type **types_pntr = &types[2];
  80
  81     types[0] = &ffi_type_pointer;
  82     values[0] = &env;
  83
  84     types[1] = &ffi_type_pointer;
  85     values[1] = class ? &class : (void*)opntr++;
  86
  87     SCAN_SIG(sig, DOUBLE, SINGLE);
  88
  89     if(ffi_prep_cif(&cif, FFI_DEFAULT_ABI, num_args, sig2ffi(*sig), types) == FFI_OK) {
  90         ffi_call(&cif, FFI_FN(func), ostack, values);
  91
  92         if(*sig == 'J' || *sig == 'D')
  93             ostack += 2;
  94         else if(*sig != 'V')
  95             ostack++;
  96     }
  97
  98     return ostack;
  99 }
 100 #endif