gtk/gdk/gdkarrayimpl.c
Benjamin Otte 9c636a6136 array: Compute new size properly
Using "1 << x" means that we are shifting a signed 32bit integer, but we
want a gsize, which is an unsigned 64bit integer.

So now we don't overflow anymore if the array reaches a size of 2GB.
2023-09-26 11:08:59 +02:00

321 lines
7.4 KiB
C

/*
* Copyright © 2020 Benjamin Otte
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* Authors: Benjamin Otte <otte@gnome.org>
*/
#include <glib.h>
G_BEGIN_DECLS
#ifndef GDK_ARRAY_TYPE_NAME
#define GDK_ARRAY_TYPE_NAME GdkArray
#endif
#ifndef GDK_ARRAY_NAME
#define GDK_ARRAY_NAME gdk_array
#endif
#ifndef GDK_ARRAY_ELEMENT_TYPE
#define GDK_ARRAY_ELEMENT_TYPE gpointer
#endif
#ifdef GDK_ARRAY_PREALLOC
#if GDK_ARRAY_PREALLOC == 0
#undef GDK_ARRAY_PREALLOC
#endif
#endif
#ifdef GDK_ARRAY_NULL_TERMINATED
#define GDK_ARRAY_REAL_SIZE(_size) ((_size) + 1)
#else
#define GDK_ARRAY_REAL_SIZE(_size) (_size)
#endif
/* make this readable */
#define _T_ GDK_ARRAY_ELEMENT_TYPE
#define GdkArray GDK_ARRAY_TYPE_NAME
#define gdk_array_paste_more(GDK_ARRAY_NAME, func_name) GDK_ARRAY_NAME ## _ ## func_name
#define gdk_array_paste(GDK_ARRAY_NAME, func_name) gdk_array_paste_more (GDK_ARRAY_NAME, func_name)
#define gdk_array(func_name) gdk_array_paste (GDK_ARRAY_NAME, func_name)
typedef struct GdkArray GdkArray;
struct GdkArray
{
_T_ *start;
_T_ *end;
_T_ *end_allocation;
#ifdef GDK_ARRAY_PREALLOC
_T_ preallocated[GDK_ARRAY_REAL_SIZE(GDK_ARRAY_PREALLOC)];
#endif
};
/* no G_GNUC_UNUSED here, if you don't use an array type, remove it. */
static inline void
gdk_array(init) (GdkArray *self)
{
#ifdef GDK_ARRAY_PREALLOC
self->start = self->preallocated;
self->end = self->start;
self->end_allocation = self->start + GDK_ARRAY_PREALLOC;
#ifdef GDK_ARRAY_NULL_TERMINATED
*self->start = *(_T_[1]) { 0 };
#endif
#else
self->start = NULL;
self->end = NULL;
self->end_allocation = NULL;
#endif
}
G_GNUC_UNUSED static inline gsize
gdk_array(get_capacity) (const GdkArray *self)
{
return self->end_allocation - self->start;
}
G_GNUC_UNUSED static inline gsize
gdk_array(get_size) (const GdkArray *self)
{
return self->end - self->start;
}
static inline void
gdk_array(free_elements) (_T_ *start,
_T_ *end)
{
#ifdef GDK_ARRAY_FREE_FUNC
_T_ *e;
for (e = start; e < end; e++)
#ifdef GDK_ARRAY_BY_VALUE
GDK_ARRAY_FREE_FUNC (e);
#else
GDK_ARRAY_FREE_FUNC (*e);
#endif
#endif
}
/* no G_GNUC_UNUSED here */
static inline void
gdk_array(clear) (GdkArray *self)
{
gdk_array(free_elements) (self->start, self->end);
#ifdef GDK_ARRAY_PREALLOC
if (self->start != self->preallocated)
#endif
g_free (self->start);
gdk_array(init) (self);
}
/*
* gdk_array_steal:
* @self: the array
*
* Steals all data in the array and clears the array.
*
* If you need to know the size of the data, you should query it
* beforehand.
*
* Returns: The array's data
**/
G_GNUC_UNUSED static inline _T_ *
gdk_array(steal) (GdkArray *self)
{
_T_ *result;
#ifdef GDK_ARRAY_PREALLOC
if (self->start == self->preallocated)
{
gsize size = GDK_ARRAY_REAL_SIZE (gdk_array(get_size) (self));
result = g_new (_T_, size);
memcpy (result, self->preallocated, sizeof (_T_) * size);
}
else
#endif
result = self->start;
gdk_array(init) (self);
return result;
}
G_GNUC_UNUSED static inline _T_ *
gdk_array(get_data) (const GdkArray *self)
{
return self->start;
}
G_GNUC_UNUSED static inline _T_ *
gdk_array(index) (const GdkArray *self,
gsize pos)
{
return self->start + pos;
}
G_GNUC_UNUSED static inline gboolean
gdk_array(is_empty) (const GdkArray *self)
{
return self->end == self->start;
}
G_GNUC_UNUSED static inline void
gdk_array(reserve) (GdkArray *self,
gsize n)
{
gsize new_size, size;
if (n <= gdk_array(get_capacity) (self))
return;
size = gdk_array(get_size) (self);
new_size = ((gsize) 1) << g_bit_storage (MAX (GDK_ARRAY_REAL_SIZE (n), 16) - 1);
#ifdef GDK_ARRAY_PREALLOC
if (self->start == self->preallocated)
{
self->start = g_new (_T_, new_size);
memcpy (self->start, self->preallocated, sizeof (_T_) * GDK_ARRAY_REAL_SIZE (size));
}
else
#endif
#ifdef GDK_ARRAY_NULL_TERMINATED
if (self->start == NULL)
{
self->start = g_new (_T_, new_size);
*self->start = *(_T_[1]) { 0 };
}
else
#endif
self->start = g_renew (_T_, self->start, new_size);
self->end = self->start + size;
self->end_allocation = self->start + new_size;
#ifdef GDK_ARRAY_NULL_TERMINATED
self->end_allocation--;
#endif
}
G_GNUC_UNUSED static inline void
gdk_array(splice) (GdkArray *self,
gsize pos,
gsize removed,
gboolean stolen,
_T_ *additions,
gsize added)
{
gsize size;
gsize remaining;
size = gdk_array(get_size) (self);
g_assert (pos + removed <= size);
remaining = size - pos - removed;
if (!stolen)
gdk_array(free_elements) (gdk_array(index) (self, pos),
gdk_array(index) (self, pos + removed));
gdk_array(reserve) (self, size - removed + added);
if (GDK_ARRAY_REAL_SIZE (remaining) && removed != added)
memmove (gdk_array(index) (self, pos + added),
gdk_array(index) (self, pos + removed),
GDK_ARRAY_REAL_SIZE (remaining) * sizeof (_T_));
if (added)
{
if (additions)
memcpy (gdk_array(index) (self, pos),
additions,
added * sizeof (_T_));
#ifndef GDK_ARRAY_NO_MEMSET
else
memset (gdk_array(index) (self, pos), 0, added * sizeof (_T_));
#endif
}
/* might overflow, but does the right thing */
self->end += added - removed;
}
G_GNUC_UNUSED static void
gdk_array(set_size) (GdkArray *self,
gsize new_size)
{
gsize old_size = gdk_array(get_size) (self);
if (new_size > old_size)
gdk_array(splice) (self, old_size, 0, FALSE, NULL, new_size - old_size);
else
gdk_array(splice) (self, new_size, old_size - new_size, FALSE, NULL, 0);
}
G_GNUC_UNUSED static void
gdk_array(append) (GdkArray *self,
#ifdef GDK_ARRAY_BY_VALUE
_T_ *value)
#else
_T_ value)
#endif
{
gdk_array(splice) (self,
gdk_array(get_size) (self),
0,
FALSE,
#ifdef GDK_ARRAY_BY_VALUE
value,
#else
&value,
#endif
1);
}
#ifdef GDK_ARRAY_BY_VALUE
G_GNUC_UNUSED static _T_ *
gdk_array(get) (const GdkArray *self,
gsize pos)
{
return gdk_array(index) (self, pos);
}
#else
G_GNUC_UNUSED static _T_
gdk_array(get) (const GdkArray *self,
gsize pos)
{
return *gdk_array(index) (self, pos);
}
#endif
#ifndef GDK_ARRAY_NO_UNDEF
#undef _T_
#undef GdkArray
#undef gdk_array_paste_more
#undef gdk_array_paste
#undef gdk_array
#undef GDK_ARRAY_REAL_SIZE
#undef GDK_ARRAY_BY_VALUE
#undef GDK_ARRAY_ELEMENT_TYPE
#undef GDK_ARRAY_FREE_FUNC
#undef GDK_ARRAY_NAME
#undef GDK_ARRAY_NULL_TERMINATED
#undef GDK_ARRAY_PREALLOC
#undef GDK_ARRAY_TYPE_NAME
#undef GDK_ARRAY_NO_MEMSET
#endif