1/* -----------------------------------------------------------------------
2   prep_cif.c - Copyright (c) 1996, 1998, 2007  Red Hat, Inc.
3
4   Permission is hereby granted, free of charge, to any person obtaining
5   a copy of this software and associated documentation files (the
6   ``Software''), to deal in the Software without restriction, including
7   without limitation the rights to use, copy, modify, merge, publish,
8   distribute, sublicense, and/or sell copies of the Software, and to
9   permit persons to whom the Software is furnished to do so, subject to
10   the following conditions:
11
12   The above copyright notice and this permission notice shall be included
13   in all copies or substantial portions of the Software.
14
15   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
16   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18   NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22   DEALINGS IN THE SOFTWARE.
23   ----------------------------------------------------------------------- */
24
25#include <ffi.h>
26#include <ffi_common.h>
27#include <stdlib.h>
28
29/* Round up to FFI_SIZEOF_ARG. */
30
31#define STACK_ARG_SIZE(x) ALIGN(x, FFI_SIZEOF_ARG)
32
33/* Perform machine independent initialization of aggregate type
34   specifications. */
35
36static ffi_status initialize_aggregate(ffi_type *arg)
37{
38  ffi_type **ptr;
39
40  FFI_ASSERT(arg != NULL);
41
42  FFI_ASSERT(arg->elements != NULL);
43  FFI_ASSERT(arg->size == 0);
44  FFI_ASSERT(arg->alignment == 0);
45
46  ptr = &(arg->elements[0]);
47
48  while ((*ptr) != NULL)
49    {
50      if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
51	return FFI_BAD_TYPEDEF;
52
53      /* Perform a sanity check on the argument type */
54      FFI_ASSERT_VALID_TYPE(*ptr);
55
56      arg->size = ALIGN(arg->size, (*ptr)->alignment);
57      arg->size += (*ptr)->size;
58
59      arg->alignment = (arg->alignment > (*ptr)->alignment) ?
60	arg->alignment : (*ptr)->alignment;
61
62      ptr++;
63    }
64
65  /* Structure size includes tail padding.  This is important for
66     structures that fit in one register on ABIs like the PowerPC64
67     Linux ABI that right justify small structs in a register.
68     It's also needed for nested structure layout, for example
69     struct A { long a; char b; }; struct B { struct A x; char y; };
70     should find y at an offset of 2*sizeof(long) and result in a
71     total size of 3*sizeof(long).  */
72  arg->size = ALIGN (arg->size, arg->alignment);
73
74  if (arg->size == 0)
75    return FFI_BAD_TYPEDEF;
76  else
77    return FFI_OK;
78}
79
80#ifndef __CRIS__
81/* The CRIS ABI specifies structure elements to have byte
82   alignment only, so it completely overrides this functions,
83   which assumes "natural" alignment and padding.  */
84
85/* Perform machine independent ffi_cif preparation, then call
86   machine dependent routine. */
87
88ffi_status ffi_prep_cif(ffi_cif *cif, ffi_abi abi, unsigned int nargs,
89			ffi_type *rtype, ffi_type **atypes)
90{
91  unsigned bytes = 0;
92  unsigned int i;
93  ffi_type **ptr;
94
95  FFI_ASSERT(cif != NULL);
96  FFI_ASSERT((abi > FFI_FIRST_ABI) && (abi <= FFI_DEFAULT_ABI));
97
98  cif->abi = abi;
99  cif->arg_types = atypes;
100  cif->nargs = nargs;
101  cif->rtype = rtype;
102
103  cif->flags = 0;
104
105  /* Initialize the return type if necessary */
106  if ((cif->rtype->size == 0) && (initialize_aggregate(cif->rtype) != FFI_OK))
107    return FFI_BAD_TYPEDEF;
108
109  /* Perform a sanity check on the return type */
110  FFI_ASSERT_VALID_TYPE(cif->rtype);
111
112  /* x86-64 and s390 stack space allocation is handled in prep_machdep.  */
113#if !defined M68K && !defined __x86_64__ && !defined S390 && !defined PA
114  /* Make space for the return structure pointer */
115  if (cif->rtype->type == FFI_TYPE_STRUCT
116#ifdef SPARC
117      && (cif->abi != FFI_V9 || cif->rtype->size > 32)
118#endif
119#ifdef X86_DARWIN
120      && (cif->rtype->size > 8)
121#endif
122     )
123    bytes = STACK_ARG_SIZE(sizeof(void*));
124#endif
125
126  for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
127    {
128
129      /* Initialize any uninitialized aggregate type definitions */
130      if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
131	return FFI_BAD_TYPEDEF;
132
133      /* Perform a sanity check on the argument type, do this
134	 check after the initialization.  */
135      FFI_ASSERT_VALID_TYPE(*ptr);
136
137#if !defined __x86_64__ && !defined S390 && !defined PA
138#ifdef SPARC
139      if (((*ptr)->type == FFI_TYPE_STRUCT
140	   && ((*ptr)->size > 16 || cif->abi != FFI_V9))
141	  || ((*ptr)->type == FFI_TYPE_LONGDOUBLE
142	      && cif->abi != FFI_V9))
143	bytes += sizeof(void*);
144      else
145#endif
146	{
147	  /* Add any padding if necessary */
148	  if (((*ptr)->alignment - 1) & bytes)
149	    bytes = ALIGN(bytes, (*ptr)->alignment);
150
151	  bytes += STACK_ARG_SIZE((*ptr)->size);
152	}
153#endif
154    }
155
156  cif->bytes = bytes;
157
158  /* Perform machine dependent cif processing */
159  return ffi_prep_cif_machdep(cif);
160}
161#endif /* not __CRIS__ */
162
163#if FFI_CLOSURES
164
165ffi_status
166ffi_prep_closure (ffi_closure* closure,
167		  ffi_cif* cif,
168		  void (*fun)(ffi_cif*,void*,void**,void*),
169		  void *user_data)
170{
171  return ffi_prep_closure_loc (closure, cif, fun, user_data, closure);
172}
173
174#endif
175