/* The following three functions can be used to determine how a
structure is laid out by the compiler. For example:
struct objc_struct_layout layout;
int i;
objc_layout_structure (type, &layout);
while (objc_layout_structure_next_member (&layout))
{
int position, align;
const char *type;
objc_layout_structure_get_info (&layout, &position, &align, &type);
printf ("element %d has offset %d, alignment %d\n",
i++, position, align);
}
These functions are used by objc_sizeof_type and objc_alignof_type
functions to compute the size and alignment of structures. The
previous method of computing the size and alignment of a structure
was not working on some architectures, particularly on AIX, and in
the presence of bitfields inside the structure. */
void
objc_layout_structure (const char *type,
struct objc_struct_layout *layout)
{
const char *ntype;
if (*type != _C_UNION_B && *type != _C_STRUCT_B)
{
_objc_abort ("record (or union) type expected in objc_layout_structure, got %s\n",
type);
}
type ++;
layout->original_type = type;
/* Skip "<name>=" if any. Avoid embedded structures and unions. */
ntype = type;
while (*ntype != _C_STRUCT_E && *ntype != _C_STRUCT_B && *ntype != _C_UNION_B
&& *ntype++ != '=')
/* do nothing */;
/* If there's a "<name>=", ntype - 1 points to '='; skip the the name */
if (*(ntype - 1) == '=')
type = ntype;
layout->type = type;
layout->prev_type = NULL;
layout->record_size = 0;
layout->record_align = BITS_PER_UNIT;
layout->record_align = MAX (layout->record_align, STRUCTURE_SIZE_BOUNDARY);
}
void *
objc_realloc (void *mem, size_t size)
{
void *res = (void *)(GC_realloc (mem, size));
if (! res)
_objc_abort ("Virtual memory exhausted\n");
return res;
}
void *
objc_atomic_malloc (size_t size)
{
void *res = (void *)(GC_malloc_atomic (size));
if (! res)
_objc_abort ("Virtual memory exhausted\n");
return res;
}
void *
objc_calloc (size_t nelem, size_t size)
{
/* Note that GC_malloc returns cleared memory (see documentation) so
there is no need to clear it. */
void *res = (void *)(GC_malloc (nelem * size));
if (! res)
_objc_abort ("Virtual memory exhausted\n");
return res;
}
inline
const char *
objc_skip_typespec (const char *type)
{
type = objc_skip_variable_name (type);
type = objc_skip_type_qualifiers (type);
switch (*type) {
case _C_ID:
/* An id may be annotated by the actual type if it is known
with the @"ClassName" syntax */
if (*++type != '"')
return type;
else
{
while (*++type != '"')
/* do nothing */;
return type + 1;
}
/* The following are one character type codes */
case _C_CLASS:
case _C_SEL:
case _C_CHR:
case _C_UCHR:
case _C_CHARPTR:
case _C_ATOM:
case _C_SHT:
case _C_USHT:
case _C_INT:
case _C_UINT:
case _C_LNG:
case _C_BOOL:
case _C_ULNG:
case _C_LNG_LNG:
case _C_ULNG_LNG:
case _C_FLT:
case _C_DBL:
case _C_LNG_DBL:
case _C_VOID:
case _C_UNDEF:
return ++type;
break;
case _C_COMPLEX:
return type + 2;
break;
case _C_ARY_B:
/* skip digits, typespec and closing ']' */
while (isdigit ((unsigned char)*++type))
;
type = objc_skip_typespec (type);
if (*type == _C_ARY_E)
return ++type;
else
{
_objc_abort ("bad array type %s\n", type);
return 0;
}
case _C_VECTOR:
/* Skip '!' */
type++;
/* Skip '[' */
type++;
/* Skip digits (size) */
while (isdigit ((unsigned char)*type))
type++;
/* Skip ',' */
type++;
/* Skip digits (alignment) */
while (isdigit ((unsigned char)*type))
type++;
/* Skip typespec. */
type = objc_skip_typespec (type);
/* Skip closing ']'. */
if (*type == _C_ARY_E)
return ++type;
else
{
_objc_abort ("bad vector type %s\n", type);
return 0;
}
case _C_BFLD:
/* The GNU encoding of bitfields is: b 'position' 'type'
'size'. */
while (isdigit ((unsigned char)*++type))
; /* skip position */
while (isdigit ((unsigned char)*++type))
; /* skip type and size */
return type;
case _C_STRUCT_B:
/* skip name, and elements until closing '}' */
while (*type != _C_STRUCT_E && *type++ != '=')
;
while (*type != _C_STRUCT_E)
{
type = objc_skip_typespec (type);
}
return ++type;
case _C_UNION_B:
/* skip name, and elements until closing ')' */
while (*type != _C_UNION_E && *type++ != '=')
;
while (*type != _C_UNION_E)
{
type = objc_skip_typespec (type);
}
return ++type;
case _C_PTR:
/* Just skip the following typespec */
return objc_skip_typespec (++type);
default:
{
_objc_abort ("unknown type %s\n", type);
return 0;
}
}
}
int
objc_alignof_type (const char *type)
{
type = objc_skip_variable_name (type);
switch (*type) {
case _C_BOOL:
return __alignof__ (_Bool);
break;
case _C_ID:
return __alignof__ (id);
break;
case _C_CLASS:
return __alignof__ (Class);
break;
case _C_SEL:
return __alignof__ (SEL);
break;
case _C_CHR:
return __alignof__ (char);
break;
case _C_UCHR:
return __alignof__ (unsigned char);
break;
case _C_SHT:
return __alignof__ (short);
break;
case _C_USHT:
return __alignof__ (unsigned short);
break;
case _C_INT:
return __alignof__ (int);
break;
case _C_UINT:
return __alignof__ (unsigned int);
break;
case _C_LNG:
return __alignof__ (long);
break;
case _C_ULNG:
return __alignof__ (unsigned long);
break;
case _C_LNG_LNG:
return __alignof__ (long long);
break;
case _C_ULNG_LNG:
return __alignof__ (unsigned long long);
break;
case _C_FLT:
return __alignof__ (float);
break;
case _C_DBL:
return __alignof__ (double);
break;
case _C_LNG_DBL:
return __alignof__ (long double);
break;
case _C_PTR:
case _C_ATOM:
case _C_CHARPTR:
return __alignof__ (char *);
break;
case _C_ARY_B:
while (isdigit ((unsigned char)*++type))
/* do nothing */;
return objc_alignof_type (type);
case _C_VECTOR:
{
/* Skip the '!'. */
type++;
/* Skip the '['. */
type++;
/* Skip the size. */
while (isdigit ((unsigned char)*type))
type++;
/* Skip the ','. */
type++;
/* The alignment in bytes is the following number. */
return atoi (type);
}
case _C_STRUCT_B:
case _C_UNION_B:
{
struct objc_struct_layout layout;
unsigned int align;
objc_layout_structure (type, &layout);
while (objc_layout_structure_next_member (&layout))
/* do nothing */;
objc_layout_finish_structure (&layout, NULL, &align);
return align;
}
case _C_COMPLEX:
{
type++; /* Skip after the 'j'. */
switch (*type)
{
case _C_CHR:
return __alignof__ (_Complex char);
break;
case _C_UCHR:
return __alignof__ (_Complex unsigned char);
break;
case _C_SHT:
return __alignof__ (_Complex short);
break;
case _C_USHT:
return __alignof__ (_Complex unsigned short);
break;
case _C_INT:
return __alignof__ (_Complex int);
break;
case _C_UINT:
return __alignof__ (_Complex unsigned int);
break;
case _C_LNG:
return __alignof__ (_Complex long);
break;
case _C_ULNG:
return __alignof__ (_Complex unsigned long);
break;
case _C_LNG_LNG:
return __alignof__ (_Complex long long);
break;
case _C_ULNG_LNG:
return __alignof__ (_Complex unsigned long long);
break;
case _C_FLT:
return __alignof__ (_Complex float);
break;
case _C_DBL:
return __alignof__ (_Complex double);
break;
case _C_LNG_DBL:
return __alignof__ (_Complex long double);
break;
default:
{
_objc_abort ("unknown complex type %s\n", type);
return 0;
}
}
}
default:
{
_objc_abort ("unknown type %s\n", type);
return 0;
}
}
}
int
objc_sizeof_type (const char *type)
{
type = objc_skip_variable_name (type);
switch (*type) {
case _C_BOOL:
return sizeof (_Bool);
break;
case _C_ID:
return sizeof (id);
break;
case _C_CLASS:
return sizeof (Class);
break;
case _C_SEL:
return sizeof (SEL);
break;
case _C_CHR:
return sizeof (char);
break;
case _C_UCHR:
return sizeof (unsigned char);
break;
case _C_SHT:
return sizeof (short);
break;
case _C_USHT:
return sizeof (unsigned short);
break;
case _C_INT:
return sizeof (int);
break;
case _C_UINT:
return sizeof (unsigned int);
break;
case _C_LNG:
return sizeof (long);
break;
case _C_ULNG:
return sizeof (unsigned long);
break;
case _C_LNG_LNG:
return sizeof (long long);
break;
case _C_ULNG_LNG:
return sizeof (unsigned long long);
break;
case _C_FLT:
return sizeof (float);
break;
case _C_DBL:
return sizeof (double);
break;
case _C_LNG_DBL:
return sizeof (long double);
break;
case _C_VOID:
return sizeof (void);
break;
case _C_PTR:
case _C_ATOM:
case _C_CHARPTR:
return sizeof (char *);
break;
case _C_ARY_B:
{
int len = atoi (type + 1);
while (isdigit ((unsigned char)*++type))
;
return len * objc_aligned_size (type);
}
break;
case _C_VECTOR:
{
/* Skip the '!'. */
type++;
/* Skip the '['. */
type++;
/* The size in bytes is the following number. */
int size = atoi (type);
return size;
}
break;
case _C_BFLD:
{
/* The GNU encoding of bitfields is: b 'position' 'type'
'size'. */
int position, size;
int startByte, endByte;
position = atoi (type + 1);
while (isdigit ((unsigned char)*++type))
;
size = atoi (type + 1);
startByte = position / BITS_PER_UNIT;
endByte = (position + size) / BITS_PER_UNIT;
return endByte - startByte;
}
case _C_UNION_B:
case _C_STRUCT_B:
{
struct objc_struct_layout layout;
unsigned int size;
objc_layout_structure (type, &layout);
while (objc_layout_structure_next_member (&layout))
/* do nothing */ ;
objc_layout_finish_structure (&layout, &size, NULL);
return size;
}
case _C_COMPLEX:
{
type++; /* Skip after the 'j'. */
switch (*type)
{
case _C_CHR:
return sizeof (_Complex char);
break;
case _C_UCHR:
return sizeof (_Complex unsigned char);
break;
case _C_SHT:
return sizeof (_Complex short);
break;
case _C_USHT:
return sizeof (_Complex unsigned short);
break;
case _C_INT:
return sizeof (_Complex int);
break;
case _C_UINT:
return sizeof (_Complex unsigned int);
break;
case _C_LNG:
return sizeof (_Complex long);
break;
case _C_ULNG:
return sizeof (_Complex unsigned long);
break;
case _C_LNG_LNG:
return sizeof (_Complex long long);
break;
case _C_ULNG_LNG:
return sizeof (_Complex unsigned long long);
break;
case _C_FLT:
return sizeof (_Complex float);
break;
case _C_DBL:
return sizeof (_Complex double);
break;
case _C_LNG_DBL:
return sizeof (_Complex long double);
break;
default:
{
/* FIXME: Is this so bad that we have to abort the
entire program ? (it applies to all the other
_objc_abort calls in this file).
*/
_objc_abort ("unknown complex type %s\n", type);
return 0;
}
}
}
default:
{
_objc_abort ("unknown type %s\n", type);
return 0;
}
}
}
