binutils-gdb/gdb/gdb_obstack.h

130 lines
4.0 KiB
C++

/* Obstack wrapper for GDB.
Copyright (C) 2002-2018 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#if !defined (GDB_OBSTACK_H)
#define GDB_OBSTACK_H 1
#include "obstack.h"
/* Utility macros - wrap obstack alloc into something more robust. */
template <typename T>
static inline T*
obstack_zalloc (struct obstack *ob)
{
static_assert (IsMallocable<T>::value, "Trying to use OBSTACK_ZALLOC with a \
non-POD data type. Use obstack_new instead.");
return ((T *) memset (obstack_alloc (ob, sizeof (T)), 0, sizeof (T)));
}
#define OBSTACK_ZALLOC(OBSTACK,TYPE) obstack_zalloc<TYPE> ((OBSTACK))
template <typename T>
static inline T *
obstack_calloc (struct obstack *ob, size_t number)
{
static_assert (IsMallocable<T>::value, "Trying to use OBSTACK_CALLOC with a \
non-POD data type. Use obstack_new instead.");
return ((T *) memset (obstack_alloc (ob, number * sizeof (T)), 0,
number * sizeof (T)));
}
#define OBSTACK_CALLOC(OBSTACK,NUMBER,TYPE) \
obstack_calloc<TYPE> ((OBSTACK), (NUMBER))
/* Allocate an object on OB and call its constructor. */
template <typename T, typename... Args>
static inline T*
obstack_new (struct obstack *ob, Args&&... args)
{
T* object = (T *) obstack_alloc (ob, sizeof (T));
object = new (object) T (std::forward<Args> (args)...);
return object;
}
/* Unless explicitly specified, GDB obstacks always use xmalloc() and
xfree(). */
/* Note: ezannoni 2004-02-09: One could also specify the allocation
functions using a special init function for each obstack,
obstack_specify_allocation. However we just use obstack_init and
let these defines here do the job. While one could argue the
superiority of one approach over the other, we just chose one
throughout. */
#define obstack_chunk_alloc xmalloc
#define obstack_chunk_free xfree
#define obstack_grow_str(OBSTACK,STRING) \
obstack_grow (OBSTACK, STRING, strlen (STRING))
#define obstack_grow_str0(OBSTACK,STRING) \
obstack_grow0 (OBSTACK, STRING, strlen (STRING))
#define obstack_grow_wstr(OBSTACK, WSTRING) \
obstack_grow (OBSTACK, WSTRING, sizeof (gdb_wchar_t) * gdb_wcslen (WSTRING))
/* Concatenate NULL terminated variable argument list of `const char
*' strings; return the new string. Space is found in the OBSTACKP.
Argument list must be terminated by a sentinel expression `(char *)
NULL'. */
extern char *obconcat (struct obstack *obstackp, ...) ATTRIBUTE_SENTINEL;
/* Duplicate STRING, returning an equivalent string that's allocated on the
obstack OBSTACKP. */
extern char *obstack_strdup (struct obstack *obstackp, const char *string);
/* An obstack that frees itself on scope exit. */
struct auto_obstack : obstack
{
auto_obstack ()
{ obstack_init (this); }
~auto_obstack ()
{ obstack_free (this, NULL); }
/* Free all memory in the obstack but leave it valid for further
allocation. */
void clear ()
{ obstack_free (this, obstack_base (this)); }
};
/* Objects are allocated on obstack instead of heap. */
struct allocate_on_obstack
{
allocate_on_obstack () = default;
void* operator new (size_t size, struct obstack *obstack)
{
return obstack_alloc (obstack, size);
}
void* operator new[] (size_t size, struct obstack *obstack)
{
return obstack_alloc (obstack, size);
}
void operator delete (void *memory) {}
void operator delete[] (void *memory) {}
};
#endif