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/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2004 Red Hat, Inc
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is University of Southern
* California.
*
* Contributor(s):
* Kristian Høgsberg <krh@redhat.com>
* Carl Worth <cworth@cworth.org>
*/
#include "cairoint.h"
#include "cairo-array-private.h"
#include "cairo-error-private.h"
/**
* _cairo_array_init:
*
* Initialize a new #cairo_array_t object to store objects each of size
* @element_size.
*
* The #cairo_array_t object provides grow-by-doubling storage. It
* never interprets the data passed to it, nor does it provide any
* sort of callback mechanism for freeing resources held onto by
* stored objects.
*
* When finished using the array, _cairo_array_fini() should be
* called to free resources allocated during use of the array.
**/
void
_cairo_array_init (cairo_array_t *array, unsigned int element_size)
{
array->size = 0;
array->num_elements = 0;
array->element_size = element_size;
array->elements = NULL;
}
/**
* _cairo_array_fini:
* @array: A #cairo_array_t
*
* Free all resources associated with @array. After this call, @array
* should not be used again without a subsequent call to
* _cairo_array_init() again first.
**/
void
_cairo_array_fini (cairo_array_t *array)
{
free (array->elements);
}
/**
* _cairo_array_grow_by:
* @array: a #cairo_array_t
*
* Increase the size of @array (if needed) so that there are at least
* @additional free spaces in the array. The actual size of the array
* is always increased by doubling as many times as necessary.
**/
cairo_status_t
_cairo_array_grow_by (cairo_array_t *array, unsigned int additional)
{
char *new_elements;
unsigned int old_size = array->size;
unsigned int required_size = array->num_elements + additional;
unsigned int new_size;
/* check for integer overflow */
if (required_size > INT_MAX || required_size < array->num_elements)
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
if (CAIRO_INJECT_FAULT ())
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
if (required_size <= old_size)
return CAIRO_STATUS_SUCCESS;
if (old_size == 0)
new_size = 1;
else
new_size = old_size * 2;
while (new_size < required_size)
new_size = new_size * 2;
array->size = new_size;
new_elements = _cairo_realloc_ab (array->elements,
array->size, array->element_size);
if (unlikely (new_elements == NULL)) {
array->size = old_size;
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
}
array->elements = new_elements;
return CAIRO_STATUS_SUCCESS;
}
/**
* _cairo_array_truncate:
* @array: a #cairo_array_t
*
* Truncate size of the array to @num_elements if less than the
* current size. No memory is actually freed. The stored objects
* beyond @num_elements are simply "forgotten".
**/
void
_cairo_array_truncate (cairo_array_t *array, unsigned int num_elements)
{
if (num_elements < array->num_elements)
array->num_elements = num_elements;
}
/**
* _cairo_array_index:
* @array: a #cairo_array_t
* Returns: A pointer to the object stored at @index.
*
* If the resulting value is assigned to a pointer to an object of the same
* element_size as initially passed to _cairo_array_init() then that
* pointer may be used for further direct indexing with []. For
* example:
*
* <informalexample><programlisting>
* cairo_array_t array;
* double *values;
*
* _cairo_array_init (&array, sizeof(double));
* ... calls to _cairo_array_append() here ...
*
* values = _cairo_array_index (&array, 0);
* for (i = 0; i < _cairo_array_num_elements (&array); i++)
* ... use values[i] here ...
* </programlisting></informalexample>
**/
void *
_cairo_array_index (cairo_array_t *array, unsigned int index)
{
/* We allow an index of 0 for the no-elements case.
* This makes for cleaner calling code which will often look like:
*
* elements = _cairo_array_index (array, 0);
* for (i=0; i < num_elements; i++) {
* ... use elements[i] here ...
* }
*
* which in the num_elements==0 case gets the NULL pointer here,
* but never dereferences it.
*/
if (index == 0 && array->num_elements == 0)
return NULL;
assert (index < array->num_elements);
return array->elements + index * array->element_size;
}
/**
* _cairo_array_index_const:
* @array: a #cairo_array_t
* Returns: A pointer to the object stored at @index.
*
* If the resulting value is assigned to a pointer to an object of the same
* element_size as initially passed to _cairo_array_init() then that
* pointer may be used for further direct indexing with []. For
* example:
*
* <informalexample><programlisting>
* cairo_array_t array;
* const double *values;
*
* _cairo_array_init (&array, sizeof(double));
* ... calls to _cairo_array_append() here ...
*
* values = _cairo_array_index_const (&array, 0);
* for (i = 0; i < _cairo_array_num_elements (&array); i++)
* ... read values[i] here ...
* </programlisting></informalexample>
**/
const void *
_cairo_array_index_const (const cairo_array_t *array, unsigned int index)
{
/* We allow an index of 0 for the no-elements case.
* This makes for cleaner calling code which will often look like:
*
* elements = _cairo_array_index_const (array, 0);
* for (i=0; i < num_elements; i++) {
* ... read elements[i] here ...
* }
*
* which in the num_elements==0 case gets the NULL pointer here,
* but never dereferences it.
*/
if (index == 0 && array->num_elements == 0)
return NULL;
assert (index < array->num_elements);
return array->elements + index * array->element_size;
}
/**
* _cairo_array_copy_element:
* @array: a #cairo_array_t
*
* Copy a single element out of the array from index @index into the
* location pointed to by @dst.
**/
void
_cairo_array_copy_element (const cairo_array_t *array,
unsigned int index,
void *dst)
{
memcpy (dst, _cairo_array_index_const (array, index), array->element_size);
}
/**
* _cairo_array_append:
* @array: a #cairo_array_t
*
* Append a single item onto the array by growing the array by at
* least one element, then copying element_size bytes from @element
* into the array. The address of the resulting object within the
* array can be determined with:
*
* _cairo_array_index (array, _cairo_array_num_elements (array) - 1);
*
* Return value: %CAIRO_STATUS_SUCCESS if successful or
* %CAIRO_STATUS_NO_MEMORY if insufficient memory is available for the
* operation.
**/
cairo_status_t
_cairo_array_append (cairo_array_t *array,
const void *element)
{
return _cairo_array_append_multiple (array, element, 1);
}
/**
* _cairo_array_append_multiple:
* @array: a #cairo_array_t
*
* Append one or more items onto the array by growing the array by
* @num_elements, then copying @num_elements * element_size bytes from
* @elements into the array.
*
* Return value: %CAIRO_STATUS_SUCCESS if successful or
* %CAIRO_STATUS_NO_MEMORY if insufficient memory is available for the
* operation.
**/
cairo_status_t
_cairo_array_append_multiple (cairo_array_t *array,
const void *elements,
unsigned int num_elements)
{
cairo_status_t status;
void *dest;
status = _cairo_array_allocate (array, num_elements, &dest);
if (unlikely (status))
return status;
memcpy (dest, elements, num_elements * array->element_size);
return CAIRO_STATUS_SUCCESS;
}
/**
* _cairo_array_allocate:
* @array: a #cairo_array_t
*
* Allocate space at the end of the array for @num_elements additional
* elements, providing the address of the new memory chunk in
* @elements. This memory will be uninitialized, but will be accounted
* for in the return value of _cairo_array_num_elements().
*
* Return value: %CAIRO_STATUS_SUCCESS if successful or
* %CAIRO_STATUS_NO_MEMORY if insufficient memory is available for the
* operation.
**/
cairo_status_t
_cairo_array_allocate (cairo_array_t *array,
unsigned int num_elements,
void **elements)
{
cairo_status_t status;
status = _cairo_array_grow_by (array, num_elements);
if (unlikely (status))
return status;
assert (array->num_elements + num_elements <= array->size);
*elements = array->elements + array->num_elements * array->element_size;
array->num_elements += num_elements;
return CAIRO_STATUS_SUCCESS;
}
/**
* _cairo_array_num_elements:
* @array: a #cairo_array_t
* Returns: The number of elements stored in @array.
*
* This space was left intentionally blank, but gtk-doc filled it.
**/
unsigned int
_cairo_array_num_elements (const cairo_array_t *array)
{
return array->num_elements;
}
/**
* _cairo_array_size:
* @array: a #cairo_array_t
* Returns: The number of elements for which there is currently space
* allocated in @array.
*
* This space was left intentionally blank, but gtk-doc filled it.
**/
unsigned int
_cairo_array_size (const cairo_array_t *array)
{
return array->size;
}
/**
* _cairo_user_data_array_init:
* @array: a #cairo_user_data_array_t
*
* Initializes a #cairo_user_data_array_t structure for future
* use. After initialization, the array has no keys. Call
* _cairo_user_data_array_fini() to free any allocated memory
* when done using the array.
**/
void
_cairo_user_data_array_init (cairo_user_data_array_t *array)
{
_cairo_array_init (array, sizeof (cairo_user_data_slot_t));
}
/**
* _cairo_user_data_array_fini:
* @array: a #cairo_user_data_array_t
*
* Destroys all current keys in the user data array and deallocates
* any memory allocated for the array itself.
**/
void
_cairo_user_data_array_fini (cairo_user_data_array_t *array)
{
unsigned int num_slots;
num_slots = array->num_elements;
if (num_slots) {
cairo_user_data_slot_t *slots;
slots = _cairo_array_index (array, 0);
while (num_slots--) {
cairo_user_data_slot_t *s = &slots[num_slots];
if (s->user_data != NULL && s->destroy != NULL)
s->destroy (s->user_data);
}
}
_cairo_array_fini (array);
}
/**
* _cairo_user_data_array_get_data:
* @array: a #cairo_user_data_array_t
* @key: the address of the #cairo_user_data_key_t the user data was
* attached to
*
* Returns user data previously attached using the specified
* key. If no user data has been attached with the given key this
* function returns %NULL.
*
* Return value: the user data previously attached or %NULL.
**/
void *
_cairo_user_data_array_get_data (cairo_user_data_array_t *array,
const cairo_user_data_key_t *key)
{
int i, num_slots;
cairo_user_data_slot_t *slots;
/* We allow this to support degenerate objects such as cairo_surface_nil. */
if (array == NULL)
return NULL;
num_slots = array->num_elements;
slots = _cairo_array_index (array, 0);
for (i = 0; i < num_slots; i++) {
if (slots[i].key == key)
return slots[i].user_data;
}
return NULL;
}
/**
* _cairo_user_data_array_set_data:
* @array: a #cairo_user_data_array_t
* @key: the address of a #cairo_user_data_key_t to attach the user data to
* @user_data: the user data to attach
* @destroy: a #cairo_destroy_func_t which will be called when the
* user data array is destroyed or when new user data is attached using the
* same key.
*
* Attaches user data to a user data array. To remove user data,
* call this function with the key that was used to set it and %NULL
* for @data.
*
* Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY if a
* slot could not be allocated for the user data.
**/
cairo_status_t
_cairo_user_data_array_set_data (cairo_user_data_array_t *array,
const cairo_user_data_key_t *key,
void *user_data,
cairo_destroy_func_t destroy)
{
cairo_status_t status;
int i, num_slots;
cairo_user_data_slot_t *slots, *slot, new_slot;
if (user_data) {
new_slot.key = key;
new_slot.user_data = user_data;
new_slot.destroy = destroy;
} else {
new_slot.key = NULL;
new_slot.user_data = NULL;
new_slot.destroy = NULL;
}
slot = NULL;
num_slots = array->num_elements;
slots = _cairo_array_index (array, 0);
for (i = 0; i < num_slots; i++) {
if (slots[i].key == key) {
slot = &slots[i];
if (slot->destroy && slot->user_data)
slot->destroy (slot->user_data);
break;
}
if (user_data && slots[i].user_data == NULL) {
slot = &slots[i]; /* Have to keep searching for an exact match */
}
}
if (slot) {
*slot = new_slot;
return CAIRO_STATUS_SUCCESS;
}
if (user_data == NULL)
return CAIRO_STATUS_SUCCESS;
status = _cairo_array_append (array, &new_slot);
if (unlikely (status))
return status;
return CAIRO_STATUS_SUCCESS;
}
cairo_status_t
_cairo_user_data_array_copy (cairo_user_data_array_t *dst,
const cairo_user_data_array_t *src)
{
/* discard any existing user-data */
if (dst->num_elements != 0) {
_cairo_user_data_array_fini (dst);
_cairo_user_data_array_init (dst);
}
/* don't call _cairo_array_append_multiple if there's nothing to do,
* as it assumes at least 1 element is to be appended */
if (src->num_elements == 0)
return CAIRO_STATUS_SUCCESS;
return _cairo_array_append_multiple (dst,
_cairo_array_index_const (src, 0),
src->num_elements);
}
void
_cairo_user_data_array_foreach (cairo_user_data_array_t *array,
void (*func) (const void *key,
void *elt,
void *closure),
void *closure)
{
cairo_user_data_slot_t *slots;
int i, num_slots;
num_slots = array->num_elements;
slots = _cairo_array_index (array, 0);
for (i = 0; i < num_slots; i++) {
if (slots[i].user_data != NULL)
func (slots[i].key, slots[i].user_data, closure);
}
}
void
_cairo_array_sort (const cairo_array_t *array, int (*compar)(const void *, const void *))
{
qsort (array->elements, array->num_elements, array->element_size, compar);
}