1 /* ----------------------------------------------------------------------- 2 ffi.c - Copyright (c) 1998 Red Hat, Inc. 3 4 ARM Foreign Function Interface 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, EXPRESS 18 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 20 IN NO EVENT SHALL CYGNUS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR 21 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 22 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 23 OTHER DEALINGS IN THE SOFTWARE. 24 ----------------------------------------------------------------------- */ 25 26 #include <ffi.h> 27 #include <ffi_common.h> 28 29 #include <stdlib.h> 30 31 #ifdef _WIN32_WCE 32 #pragma warning (disable : 4142) /* benign redefinition of type */ 33 #include <windows.h> 34 #endif 35 36 /* ffi_prep_args is called by the assembly routine once stack space 37 has been allocated for the function's arguments */ 38 39 /*@-exportheader@*/ 40 void ffi_prep_args(char *stack, extended_cif *ecif) 41 /*@=exportheader@*/ 42 { 43 register unsigned int i; 44 register void **p_argv; 45 register char *argp; 46 register ffi_type **p_arg; 47 48 argp = stack; 49 50 if ( ecif->cif->rtype->type == FFI_TYPE_STRUCT ) { 51 *(void **) argp = ecif->rvalue; 52 argp += 4; 53 } 54 55 p_argv = ecif->avalue; 56 57 for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types; 58 (i != 0); 59 i--, p_arg++) 60 { 61 size_t z; 62 size_t argalign = (*p_arg)->alignment; 63 64 #ifdef _WIN32_WCE 65 if (argalign > 4) 66 argalign = 4; 67 #endif 68 /* Align if necessary */ 69 if ((argalign - 1) & (unsigned) argp) { 70 argp = (char *) ALIGN(argp, argalign); 71 } 72 73 z = (*p_arg)->size; 74 if (z < sizeof(int)) 75 { 76 z = sizeof(int); 77 switch ((*p_arg)->type) 78 { 79 case FFI_TYPE_SINT8: 80 *(signed int *) argp = (signed int)*(SINT8 *)(* p_argv); 81 break; 82 83 case FFI_TYPE_UINT8: 84 *(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv); 85 break; 86 87 case FFI_TYPE_SINT16: 88 *(signed int *) argp = (signed int)*(SINT16 *)(* p_argv); 89 break; 90 91 case FFI_TYPE_UINT16: 92 *(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv); 93 break; 94 95 case FFI_TYPE_STRUCT: 96 /* *p_argv may not be aligned for a UINT32 */ 97 memcpy(argp, *p_argv, z); 98 break; 99 100 default: 101 FFI_ASSERT(0); 102 } 103 } 104 else if (z == sizeof(int)) 105 { 106 *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv); 107 } 108 else 109 { 110 memcpy(argp, *p_argv, z); 111 } 112 p_argv++; 113 argp += z; 114 } 115 116 return; 117 } 118 119 /* Perform machine dependent cif processing */ 120 ffi_status ffi_prep_cif_machdep(ffi_cif *cif) 121 { 122 /* Set the return type flag */ 123 switch (cif->rtype->type) 124 { 125 case FFI_TYPE_VOID: 126 case FFI_TYPE_STRUCT: 127 case FFI_TYPE_FLOAT: 128 case FFI_TYPE_DOUBLE: 129 case FFI_TYPE_SINT64: 130 cif->flags = (unsigned) cif->rtype->type; 131 break; 132 133 case FFI_TYPE_UINT64: 134 cif->flags = FFI_TYPE_SINT64; 135 break; 136 137 default: 138 cif->flags = FFI_TYPE_INT; 139 break; 140 } 141 142 return FFI_OK; 143 } 144 145 /*@-declundef@*/ 146 /*@-exportheader@*/ 147 extern void ffi_call_SYSV(void (*)(char *, extended_cif *), 148 /*@out@*/ extended_cif *, 149 unsigned, unsigned, 150 /*@out@*/ unsigned *, 151 void (*fn)()); 152 /*@=declundef@*/ 153 /*@=exportheader@*/ 154 155 /* Return type changed from void for ctypes */ 156 int ffi_call(/*@dependent@*/ ffi_cif *cif, 157 void (*fn)(), 158 /*@out@*/ void *rvalue, 159 /*@dependent@*/ void **avalue) 160 { 161 extended_cif ecif; 162 163 ecif.cif = cif; 164 ecif.avalue = avalue; 165 166 /* If the return value is a struct and we don't have a return */ 167 /* value address then we need to make one */ 168 169 if ((rvalue == NULL) && 170 (cif->rtype->type == FFI_TYPE_STRUCT)) 171 { 172 /*@-sysunrecog@*/ 173 ecif.rvalue = alloca(cif->rtype->size); 174 /*@=sysunrecog@*/ 175 } 176 else 177 ecif.rvalue = rvalue; 178 179 180 switch (cif->abi) 181 { 182 case FFI_SYSV: 183 /*@-usedef@*/ 184 ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes, 185 cif->flags, ecif.rvalue, fn); 186 /*@=usedef@*/ 187 break; 188 default: 189 FFI_ASSERT(0); 190 break; 191 } 192 /* I think calculating the real stack pointer delta is not useful 193 because stdcall is not supported */ 194 return 0; 195 } 196 197 /** private members **/ 198 199 static void ffi_prep_incoming_args_SYSV (char *stack, void **ret, 200 void** args, ffi_cif* cif); 201 202 /* This function is called by ffi_closure_SYSV in sysv.asm */ 203 204 unsigned int 205 ffi_closure_SYSV_inner (ffi_closure *closure, char *in_args, void *rvalue) 206 { 207 ffi_cif *cif = closure->cif; 208 void **out_args; 209 210 out_args = (void **) alloca(cif->nargs * sizeof (void *)); 211 212 /* this call will initialize out_args, such that each 213 * element in that array points to the corresponding 214 * value on the stack; and if the function returns 215 * a structure, it will re-set rvalue to point to the 216 * structure return address. */ 217 218 ffi_prep_incoming_args_SYSV(in_args, &rvalue, out_args, cif); 219 220 (closure->fun)(cif, rvalue, out_args, closure->user_data); 221 222 /* Tell ffi_closure_SYSV what the returntype is */ 223 return cif->flags; 224 } 225 226 /*@-exportheader@*/ 227 static void 228 ffi_prep_incoming_args_SYSV(char *stack, void **rvalue, 229 void **avalue, ffi_cif *cif) 230 /*@=exportheader@*/ 231 { 232 unsigned int i; 233 void **p_argv; 234 char *argp; 235 ffi_type **p_arg; 236 237 argp = stack; 238 239 if ( cif->rtype->type == FFI_TYPE_STRUCT ) { 240 *rvalue = *(void **) argp; 241 argp += 4; 242 } 243 244 p_argv = avalue; 245 246 for (i = cif->nargs, p_arg = cif->arg_types; (i != 0); i--, p_arg++) 247 { 248 size_t z; 249 size_t argalign = (*p_arg)->alignment; 250 251 #ifdef _WIN32_WCE 252 if (argalign > 4) 253 argalign = 4; 254 #endif 255 /* Align if necessary */ 256 if ((argalign - 1) & (unsigned) argp) { 257 argp = (char *) ALIGN(argp, argalign); 258 } 259 260 z = (*p_arg)->size; 261 if (z < sizeof(int)) 262 z = sizeof(int); 263 264 *p_argv = (void*) argp; 265 266 p_argv++; 267 argp += z; 268 } 269 } 270 271 /* 272 add ip, pc, #-8 ; ip = address of this trampoline == address of ffi_closure 273 ldr pc, [pc, #-4] ; jump to __fun 274 DCD __fun 275 */ 276 #define FFI_INIT_TRAMPOLINE(TRAMP,FUN) \ 277 { \ 278 unsigned int *__tramp = (unsigned int *)(TRAMP); \ 279 __tramp[0] = 0xe24fc008; /* add ip, pc, #-8 */ \ 280 __tramp[1] = 0xe51ff004; /* ldr pc, [pc, #-4] */ \ 281 __tramp[2] = (unsigned int)(FUN); \ 282 } 283 284 /* the cif must already be prep'ed */ 285 286 /* defined in sysv.asm */ 287 void ffi_closure_SYSV(void); 288 289 ffi_status 290 ffi_prep_closure (ffi_closure* closure, 291 ffi_cif* cif, 292 void (*fun)(ffi_cif*,void*,void**,void*), 293 void *user_data) 294 { 295 FFI_ASSERT (cif->abi == FFI_SYSV); 296 297 FFI_INIT_TRAMPOLINE (&closure->tramp[0], &ffi_closure_SYSV); 298 299 closure->cif = cif; 300 closure->user_data = user_data; 301 closure->fun = fun; 302 303 #ifdef _WIN32_WCE 304 /* This is important to allow calling the trampoline safely */ 305 FlushInstructionCache(GetCurrentProcess(), 0, 0); 306 #endif 307 308 return FFI_OK; 309 } 310 311
