Function fill [src]

Prototype

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

Parameters

self: *Pcgbuf: []u8

Example

 test fill {
    var r = Pcg.init(0);
    const s0: u64 = 0x9394bf54ce5d79de;
    const s1: u64 = 0x84e9c579ef59bbf7;
    r.seedTwo(s0, s1);

    const seq = [_]u32{
        2881561918,
        3063928540,
        1199791034,
        2487695858,
        1479648952,
        3247963454,
    };

    var i: u32 = 0;
    while (i < seq.len) : (i += 2) {
        var buf0: [8]u8 = undefined;
        std.mem.writeInt(u32, buf0[0..4], seq[i], .little);
        std.mem.writeInt(u32, buf0[4..8], seq[i + 1], .little);

        var buf1: [7]u8 = undefined;
        r.fill(&buf1);

        try std.testing.expect(std.mem.eql(u8, buf0[0..7], buf1[0..]));
    }
}

Source

  pub fn fill(self: *Pcg, buf: []u8) void {
    var i: usize = 0;
    const aligned_len = buf.len - (buf.len & 3);

    // Complete 4 byte segments.
    while (i < aligned_len) : (i += 4) {
        var n = self.next();
        comptime var j: usize = 0;
        inline while (j < 4) : (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;
        }
    }
}  