Function fill [src]

Prototype

pub fn fill(self: *Xoshiro256, buf: []u8) void

Parameters

self: *Xoshiro256buf: []u8

Example

 test fill {
    var r = Xoshiro256.init(0);

    const seq = [_]u64{
        0x53175d61490b23df,
        0x61da6f3dc380d507,
        0x5c0fdf91ec9a7bfc,
        0x02eebf8c3bbe5e1a,
        0x7eca04ebaf4a5eea,
        0x0543c37757f08d9a,
    };

    for (seq) |s| {
        var buf0: [8]u8 = undefined;
        var buf1: [7]u8 = undefined;
        std.mem.writeInt(u64, &buf0, s, .little);
        r.fill(&buf1);
        try std.testing.expect(std.mem.eql(u8, buf0[0..7], buf1[0..]));
    }
}

Source

  pub fn fill(self: *Xoshiro256, buf: []u8) void {
    var i: usize = 0;
    const aligned_len = buf.len - (buf.len & 7);

    // Complete 8 byte segments.
    while (i < aligned_len) : (i += 8) {
        var n = self.next();
        comptime var j: usize = 0;
        inline while (j < 8) : (j += 1) {
            buf[i + j] = @as(u8, @truncate(n));
            n >>= 8;
        }
    }

    // Remaining. (cuts the stream)
    if (i != buf.len) {
        var n = self.next();
        while (i < buf.len) : (i += 1) {
            buf[i] = @as(u8, @truncate(n));
            n >>= 8;
        }
    }
}  