archive/blender-archive
Archived
1
1
Fork 0
Code Pull Requests Packages Activity

Add an array-based generic stack structure to blenlib

Browse Source 
Very simple stack with homogeneous contents. Provides push, pop, and
is-empty operations.
This commit is contained in:
Nicholas Bishop
2012-08-05 23:29:43 +00:00
parent 958dc02774
commit b6bc308375
3 changed files with 155 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

50
source/blender/blenlib/BLI_stack.h Normal file
View File

@@ -0,0 +1,50 @@
/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* 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 2
* 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, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Contributor(s): Nicholas Bishop
*
* ***** END GPL LICENSE BLOCK *****
*
*/
#ifndef __BLI_STACK_H__
#define __BLI_STACK_H__
typedef struct BLI_Stack BLI_Stack;
/* Create a new homogeneous stack with elements of 'elem_size' bytes */
BLI_Stack *BLI_stack_new(int elem_size, const char *description);
/* Free the stack's data and the stack itself */
void BLI_stack_free(BLI_Stack *stack);
/* Copies the source value onto the stack (note that it copies
* elem_size bytes from 'src', the pointer itself is not stored) */
void BLI_stack_push(BLI_Stack *stack, void *src);
/* Retrieves and removes the top element from the stack. The value is
* copies to 'dst', which must be at least elem_size bytes.
*
* Does not reduce amount of allocated memory.
*
* If stack is empty, 'dst' will not be modified. */
void BLI_stack_pop(BLI_Stack *stack, void *dst);
/* Returns TRUE if the stack is empty, FALSE otherwise */
int BLI_stack_empty(const BLI_Stack *stack);
#endif

2
source/blender/blenlib/CMakeLists.txt
View File

@@ -81,6 +81,7 @@ set(SRC
intern/rct.c
intern/scanfill.c
intern/smallhash.c
intern/stack.c
intern/storage.c
intern/string.c
intern/string_cursor_utf8.c
@@ -135,6 +136,7 @@ set(SRC
BLI_rect.h
BLI_scanfill.h
BLI_smallhash.h
BLI_stack.h
BLI_string.h
BLI_string_cursor_utf8.h
BLI_string_utf8.h

103
source/blender/blenlib/intern/stack.c Normal file
View File

@@ -0,0 +1,103 @@
/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* 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 2
* 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, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Contributor(s): Nicholas Bishop
*
* ***** END GPL LICENSE BLOCK *****
*
*/
#include "BLI_stack.h"
#include "BLI_utildefines.h"
#include "MEM_guardedalloc.h"
#include <string.h>
typedef struct BLI_Stack {
void *data;
int totelem;
int maxelem;
int elem_size;
} BLI_Stack;
BLI_Stack *BLI_stack_new(int elem_size, const char *description)
{
BLI_Stack *stack = MEM_callocN(sizeof(*stack), description);
stack->elem_size = elem_size;
return stack;
}
void BLI_stack_free(BLI_Stack *stack)
{
if (stack) {
if (stack->data)
MEM_freeN(stack->data);
MEM_freeN(stack);
}
}
/* Gets the last element in the stack */
#define STACK_LAST_ELEM(stack__) \
(((char*)(stack__)->data) + \
((stack__)->elem_size * ((stack__)->totelem - 1)))
void BLI_stack_push(BLI_Stack *stack, void *src)
{
/* Ensure stack is large enough */
if (stack->totelem == stack->maxelem) {
if (stack->maxelem == 0) {
/* Initialize stack with space for a small hardcoded
* number of elements */
stack->maxelem = 32;
stack->data = MEM_mallocN((stack->elem_size *
stack->maxelem), AT);
}
else {
/* Double stack size */
int maxelem = stack->maxelem + stack->maxelem;
/* Check for overflow */
BLI_assert(maxelem > stack->maxelem);
stack->data = MEM_reallocN(stack->data,
(stack->elem_size *
maxelem));
stack->maxelem = maxelem;
}
}
BLI_assert(stack->totelem < stack->maxelem);
/* Copy source to end of stack */
stack->totelem++;
memcpy(STACK_LAST_ELEM(stack), src, stack->elem_size);
}
void BLI_stack_pop(BLI_Stack *stack, void *dst)
{
BLI_assert(stack->totelem > 0);
if (stack->totelem > 0) {
memcpy(dst, STACK_LAST_ELEM(stack), stack->elem_size);
stack->totelem--;
}
}
int BLI_stack_empty(const BLI_Stack *stack)
{
return stack->totelem == 0;
}