Function GC_scratch_alloc

v2/engine/boehm_gc/headers.c:114–156

/* GC_scratch_end_ptr is end point of current scratch area.		*/
 
ptr_t GC_scratch_alloc(size_t bytes)
{
    register ptr_t result = scratch_free_ptr;

    bytes += GRANULE_BYTES-1;
    bytes &= ~(GRANULE_BYTES-1);
    scratch_free_ptr += bytes;
    if (scratch_free_ptr <= GC_scratch_end_ptr) {
        return(result);
    }
    {
        word bytes_to_get = MINHINCR * HBLKSIZE;
         
        if (bytes_to_get <= bytes) {
          /* Undo the damage, and get memory directly */
	    bytes_to_get = bytes;
#	    ifdef USE_MMAP
		bytes_to_get += GC_page_size - 1;
		bytes_to_get &= ~(GC_page_size - 1);
#	    endif
   	    result = (ptr_t)GET_MEM(bytes_to_get);
            scratch_free_ptr -= bytes;
	    GC_scratch_last_end_ptr = result + bytes;
            return(result);
        }
        result = (ptr_t)GET_MEM(bytes_to_get);
        if (result == 0) {
	    if (GC_print_stats)
                GC_printf("Out of memory - trying to allocate less\n");
            scratch_free_ptr -= bytes;
	    bytes_to_get = bytes;
#	    ifdef USE_MMAP
		bytes_to_get += GC_page_size - 1;
		bytes_to_get &= ~(GC_page_size - 1);
#	    endif
            return((ptr_t)GET_MEM(bytes_to_get));
        }
        scratch_free_ptr = result;
        GC_scratch_end_ptr = scratch_free_ptr + bytes_to_get;
        GC_scratch_last_end_ptr = GC_scratch_end_ptr;
        return(GC_scratch_alloc(bytes));
    }
}

static hdr * hdr_free_list = 0;