sgl: src/cb.c annotate

sgl

starting work on SimplyGL

author	John Tsiombikas <nuclear@siggraph.org>
date	Tue, 10 May 2011 00:06:20 +0300
parents
children	648f8604d2b2

rev	line source
nuclear@0	1 #include <stdlib.h>
nuclear@0	2 #include <string.h>
nuclear@0	3 #include "sgl.h"
nuclear@0	4
nuclear@0	5 struct cbnode {
nuclear@0	6 void (*func[SGL_NUM_CALLBACKS])();
nuclear@0	7 struct cbnode *next;
nuclear@0	8 };
nuclear@0	9
nuclear@0	10 struct cbnode first_cbnode;
nuclear@0	11 struct cbnode *cb = &first_cbnode;
nuclear@0	12
nuclear@0	13 int sgl_push_callbacks(void)
nuclear@0	14 {
nuclear@0	15 struct cbnode *node;
nuclear@0	16
nuclear@0	17 if(!(node = malloc(sizeof *node))) {
nuclear@0	18 return -1;
nuclear@0	19 }
nuclear@0	20 node->next = cb;
nuclear@0	21 cb = node;
nuclear@0	22 sgl_clear_callbacks();
nuclear@0	23 return 0;
nuclear@0	24 }
nuclear@0	25
nuclear@0	26 int sgl_pop_callbacks(void)
nuclear@0	27 {
nuclear@0	28 struct cbnode *node;
nuclear@0	29
nuclear@0	30 if(!cb->next) {
nuclear@0	31 return -1;
nuclear@0	32 }
nuclear@0	33
nuclear@0	34 node = cb;
nuclear@0	35 cb = cb->next;
nuclear@0	36 free(node);
nuclear@0	37 return 0;
nuclear@0	38 }
nuclear@0	39
nuclear@0	40 void sgl_clear_callbacks(void)
nuclear@0	41 {
nuclear@0	42 memset(cb->func, 0, sizeof cb->func);
nuclear@0	43 }
nuclear@0	44
nuclear@0	45 void (sgl_callback(int idx, void (func)()))()
nuclear@0	46 {
nuclear@0	47 void (*prev)() = cb->func[idx];
nuclear@0	48 cb->func[idx] = func;
nuclear@0	49 return prev;
nuclear@0	50 }