Function string_timsort_

numpy/core/src/npysort/timsort.cpp:1381–1439

template <typename Tag>
NPY_NO_EXPORT int
string_timsort_(void *start, npy_intp num, void *varr)
{
    using type = typename Tag::type;
    PyArrayObject *arr = reinterpret_cast<PyArrayObject *>(varr);
    size_t elsize = PyArray_ITEMSIZE(arr);
    size_t len = elsize / sizeof(type);
    int ret;
    npy_intp l, n, stack_ptr, minrun;
    run stack[TIMSORT_STACK_SIZE];
    string_buffer_<Tag> buffer;

    /* Items that have zero size don't make sense to sort */
    if (len == 0) {
        return 0;
    }

    buffer.pw = NULL;
    buffer.size = 0;
    buffer.len = len;
    stack_ptr = 0;
    minrun = compute_min_run_short(num);
    /* used for insertion sort and gallop key */
    ret = resize_buffer_<Tag>(&buffer, 1);

    if (NPY_UNLIKELY(ret < 0)) {
        goto cleanup;
    }

    for (l = 0; l < num;) {
        n = count_run_<Tag>((type *)start, l, num, minrun, buffer.pw, len);
        /* both s and l are scaled by len */
        stack[stack_ptr].s = l;
        stack[stack_ptr].l = n;
        ++stack_ptr;
        ret = try_collapse_<Tag>((type *)start, stack, &stack_ptr, &buffer,
                                 len);

        if (NPY_UNLIKELY(ret < 0)) {
            goto cleanup;
        }

        l += n;
    }

    ret = force_collapse_<Tag>((type *)start, stack, &stack_ptr, &buffer, len);

    if (NPY_UNLIKELY(ret < 0)) {
        goto cleanup;
    }

    ret = 0;

cleanup:
    if (buffer.pw != NULL) {
        free(buffer.pw);
    }
    return ret;