struct DecoderWithIgnore [src]

Fields

ignored_chars: StaticBitSet(256) = undefinedThe characters to ignore.

Members

decode (Function)
decodedLenForSlice (Function)
decodedLenUpperBound (Function)

Source

  pub const DecoderWithIgnore = struct {
    /// The characters to ignore.
    ignored_chars: StaticBitSet(256) = undefined,

    /// Decodes a base64 string into a binary buffer.
    /// The output buffer must be at least `decodedLenUpperBound(encoded.len)` bytes long.
    pub fn decode(
        self: DecoderWithIgnore,
        bin: []u8,
        encoded: []const u8,
        comptime variant: Variant,
    ) error{ NoSpaceLeft, InvalidCharacter, InvalidPadding }![]const u8 {
        return decodeAny(bin, encoded, variant, self.ignored_chars);
    }

    /// Returns the decoded length of a base64 string, ignoring any characters in the ignore list.
    /// This operation does not run in constant time, but it aims to avoid leaking information about the underlying base64 string.
    pub fn decodedLenForSlice(decoder: DecoderWithIgnore, encoded: []const u8, variant: Variant) !usize {
        var b64_len = encoded.len;
        for (encoded) |c| {
            if (decoder.ignored_chars.isSet(c)) b64_len -= 1;
        }
        return base64.decodedLen(b64_len, variant);
    }

    /// Returns the maximum possible decoded size for a given input length after skipping ignored characters.
    pub fn decodedLenUpperBound(b64_len: usize) usize {
        return b64_len / 3 * 4;
    }
}  