static SLJIT_INLINE void* alloc_chunk(sljit_uw size)
{
void *retval;
#ifdef MAP_ANON
retval = mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANON, -1, 0);
#else
if (dev_zero < 0) {
if (open_dev_zero())
return NULL;
}
retval = mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, dev_zero, 0);
#endif
return (retval != MAP_FAILED) ? retval : NULL;
}
SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_FUNC sljit_allocate_stack(sljit_uw start_size, sljit_uw max_size, void *allocator_data)
{
struct sljit_stack *stack;
void *ptr;
#ifdef _WIN32
SYSTEM_INFO si;
#endif
SLJIT_UNUSED_ARG(allocator_data);
if (start_size > max_size || start_size < 1)
return NULL;
#ifdef _WIN32
if (!sljit_page_align) {
GetSystemInfo(&si);
sljit_page_align = si.dwPageSize - 1;
}
#else
if (!sljit_page_align) {
sljit_page_align = sysconf(_SC_PAGESIZE);
/* Should never happen. */
if (sljit_page_align < 0)
sljit_page_align = 4096;
sljit_page_align--;
}
#endif
stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data);
if (!stack)
return NULL;
/* Align max_size. */
max_size = (max_size + sljit_page_align) & ~sljit_page_align;
#ifdef _WIN32
ptr = VirtualAlloc(NULL, max_size, MEM_RESERVE, PAGE_READWRITE);
if (!ptr) {
SLJIT_FREE(stack, allocator_data);
return NULL;
}
stack->min_start = (sljit_u8 *)ptr;
stack->end = stack->min_start + max_size;
stack->start = stack->end;
if (sljit_stack_resize(stack, stack->end - start_size) == NULL) {
sljit_free_stack(stack, allocator_data);
return NULL;
}
#else
#ifdef MAP_ANON
ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
#else
if (dev_zero < 0) {
if (open_dev_zero()) {
SLJIT_FREE(stack, allocator_data);
return NULL;
}
}
ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, dev_zero, 0);
#endif
if (ptr == MAP_FAILED) {
SLJIT_FREE(stack, allocator_data);
return NULL;
}
stack->min_start = (sljit_u8 *)ptr;
stack->end = stack->min_start + max_size;
stack->start = stack->end - start_size;
#endif
stack->top = stack->end;
return stack;
}
