/*
* each malloc request first check size, if size >1024 ,get from free list and return
* else check if have fitted size in bin[size-1],if yes, return
* if not, check if can get from free list,if yes, return (may be need split)
* if not, check if there exist next free chunk in bin[biggersize],if yes, split and return
* if not, return NULL, out of heap error
*/
void *malloc(size_t size) {
uint32_t n = (uint32_t) size & SIZEMASK;
size_t actual_size =(uint32_t) align_to_word_boundary(size_with_header(n));
Busy_Header *b;
if (actual_size >BIN_SIZE) {
Free_Header *q = freelist_malloc(actual_size);
if (q == NULL) {
#ifdef DEBUG
printf("out of heap");
#endif
return NULL;
}
b = (Busy_Header *)q;
b->size |= BUSY_BIT;
return b;
}
else {
Free_Header *q = next_small_free(actual_size);
if (q == NULL) {
#ifdef DEBUG
printf("out of heap");
#endif
return NULL;
}
b = (Busy_Header *)q;
b->size |= BUSY_BIT;
return b;
}
return NULL;
}
void *malloc(size_t size) {
if ( heap==NULL ) { heap_init(DEFAULT_MAX_HEAP_SIZE); }
if (freelist == NULL) {
return NULL; // out of heap
}
uint32_t n = (uint32_t) size & SIZEMASK;
n = (uint32_t) align_to_word_boundary(size_with_header(n));
Free_Header *chunk = nextfree(n);
Busy_Header *b = (Busy_Header *) chunk;
b->size |= BUSY_BIT; // get busy! turn on busy bit at top of size field
return b;
}
static inline size_t request2size(size_t n) {
return align_to_word_boundary(size_with_header(n));
}