diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/stdlib/arrays.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/src/stdlib/arrays.c b/src/stdlib/arrays.c index b018012f..2941d2e0 100644 --- a/src/stdlib/arrays.c +++ b/src/stdlib/arrays.c @@ -307,6 +307,8 @@ public void Array$shuffle(Array_t *arr, OptionalClosure_t random_int64, int64_t char tmp[padded_item_size]; for (int64_t i = arr->length-1; i > 1; i--) { int64_t j = rng_fn(0, i, random_int64.userdata); + if unlikely (j < 0 || j > arr->length-1) + fail("The provided random number function returned an invalid value: ", j, " (not between 0 and ", i, ")"); memcpy(tmp, arr->data + i*padded_item_size, (size_t)padded_item_size); memcpy((void*)arr->data + i*padded_item_size, arr->data + j*padded_item_size, (size_t)padded_item_size); memcpy((void*)arr->data + j*padded_item_size, tmp, (size_t)padded_item_size); @@ -327,6 +329,8 @@ public void *Array$random(Array_t arr, OptionalClosure_t random_int64) int64_t (*rng_fn)(int64_t, int64_t, void*) = random_int64.fn; int64_t index = rng_fn(0, arr.length-1, random_int64.userdata); + if unlikely (index < 0 || index > arr.length-1) + fail("The provided random number function returned an invalid value: ", index, " (not between 0 and ", (int64_t)arr.length, ")"); return arr.data + arr.stride*index; } @@ -370,11 +374,6 @@ public Array_t Array$sample(Array_t arr, Int_t int_n, Array_t weights, OptionalC if (arr.length == 0) fail("There are no elements in this array!"); - Array_t selected = { - .data=arr.atomic ? GC_MALLOC_ATOMIC((size_t)(n * padded_item_size)) : GC_MALLOC((size_t)(n * padded_item_size)), - .length=n, - .stride=padded_item_size, .atomic=arr.atomic}; - if (weights.length != arr.length) fail("Array has ", (int64_t)arr.length, " elements, but there are ", (int64_t)weights.length, " weights given"); @@ -433,9 +432,18 @@ public Array_t Array$sample(Array_t arr, Int_t int_n, Array_t weights, OptionalC aliases[i].alias = i; double (*rng_fn)(void*) = random_num.fn ? random_num.fn : _default_random_num; + + Array_t selected = { + .data=arr.atomic ? GC_MALLOC_ATOMIC((size_t)(n * padded_item_size)) : GC_MALLOC((size_t)(n * padded_item_size)), + .length=n, + .stride=padded_item_size, .atomic=arr.atomic}; for (int64_t i = 0; i < n; i++) { - double r = (double)arr.length * rng_fn(random_num.userdata); + double r = rng_fn(random_num.userdata); + if unlikely (r < 0.0 || r >= 1.0) + fail("The random number function returned a value not between 0.0 (inclusive) and 1.0 (exclusive): ", r); + r *= (double)arr.length; int64_t index = (int64_t)r; + assert(index >= 0 && index < arr.length); if ((r - (double)index) > aliases[index].odds) index = aliases[index].alias; memcpy(selected.data + i*selected.stride, arr.data + index*arr.stride, (size_t)padded_item_size); |