Function fill [src]

Prototype

pub fn fill(self: *Isaac64, buf: []u8) void

Parameters

self: *Isaac64buf: []u8

Example

 test fill {
    var r = Isaac64.init(0);

    // from reference implementation
    const seq = [_]u64{
        0xf67dfba498e4937c,
        0x84a5066a9204f380,
        0xfee34bd5f5514dbb,
        0x4d1664739b8f80d6,
        0x8607459ab52a14aa,
        0x0e78bc5a98529e49,
        0xfe5332822ad13777,
        0x556c27525e33d01a,
        0x08643ca615f3149f,
        0xd0771faf3cb04714,
        0x30e86f68a37b008d,
        0x3074ebc0488a3adf,
        0x270645ea7a2790bc,
        0x5601a0a8d3763c6a,
        0x2f83071f53f325dd,
        0xb9090f3d42d2d2ea,
    };

    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: *Isaac64, buf: []u8) void {
    var i: usize = 0;
    const aligned_len = buf.len - (buf.len & 7);

    // Fill complete 64-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;
        }
    }

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