void *
malloc(size_t size)
{
void *ptr = NULL;
switch(mallocState) {
case UNINITIALIZED:
LOCK;
mallocState = INITIALIZING;
UNLOCK;
if(loadLibC(LIBC)) {
exit(-1);
}
LOCK;
mallocState = INITIALIZED;
UNLOCK;
case INITIALIZED:
if(size == 0) return (void *) NULL;
size += REDZONESIZE * 2;
ptr = realmalloc(size);
if(! ptr) return ptr;
realmemset(ptr, 0, size);
if(addAlloc(size, ptr) != 0) {
realfree(ptr);
return NULL;
}
return ptr + REDZONESIZE;
break;
case INITIALIZING:
if(size == 0) return NULL;
return staticMalloc(size);
break;
}
return NULL;
}
static void *
_malloc_unlocked(size_t size)
{
size_t n;
TREE *tp, *sp;
size_t o_bit1;
COUNT(nmalloc);
ASSERT(WORDSIZE == ALIGN);
/* check for size that could overflow calculations */
if (size > MAX_MALLOC) {
errno = ENOMEM;
return (NULL);
}
/* make sure that size is 0 mod ALIGN */
ROUND(size);
/* see if the last free block can be used */
if (Lfree) {
sp = BLOCK(Lfree);
n = SIZE(sp);
CLRBITS01(n);
if (n == size) {
/*
* exact match, use it as is
*/
freeidx = (freeidx + FREESIZE - 1) &
FREEMASK; /* 1 back */
flist[freeidx] = Lfree = NULL;
return (DATA(sp));
} else if (size >= MINSIZE && n > size) {
/*
* got a big enough piece
*/
freeidx = (freeidx + FREESIZE - 1) &
FREEMASK; /* 1 back */
flist[freeidx] = Lfree = NULL;
o_bit1 = SIZE(sp) & BIT1;
SIZE(sp) = n;
goto leftover;
}
}
o_bit1 = 0;
/* perform free's of space since last malloc */
cleanfree(NULL);
/* small blocks */
if (size < MINSIZE)
return (_smalloc(size));
/* search for an elt of the right size */
sp = NULL;
n = 0;
if (Root) {
tp = Root;
for (;;) {
/* branch left */
if (SIZE(tp) >= size) {
if (n == 0 || n >= SIZE(tp)) {
sp = tp;
n = SIZE(tp);
}
if (LEFT(tp))
tp = LEFT(tp);
else
break;
} else { /* branch right */
if (RIGHT(tp))
tp = RIGHT(tp);
else
break;
}
}
if (sp) {
t_delete(sp);
} else if (tp != Root) {
/* make the searched-to element the root */
t_splay(tp);
Root = tp;
}
}
/* if found none fitted in the tree */
if (!sp) {
if (Bottom && size <= SIZE(Bottom)) {
sp = Bottom;
CLRBITS01(SIZE(sp));
} else if ((sp = _morecore(size)) == NULL) /* no more memory */
return (NULL);
}
/* tell the forward neighbor that we're busy */
CLRBIT1(SIZE(NEXT(sp)));
ASSERT(ISBIT0(SIZE(NEXT(sp))));
leftover:
/* if the leftover is enough for a new free piece */
if ((n = (SIZE(sp) - size)) >= MINSIZE + WORDSIZE) {
n -= WORDSIZE;
SIZE(sp) = size;
tp = NEXT(sp);
SIZE(tp) = n|BIT0;
realfree(DATA(tp));
} else if (BOTTOM(sp))
Bottom = NULL;
/* return the allocated space */
SIZE(sp) |= BIT0 | o_bit1;
return (DATA(sp));
}