Encode Bytes as Hexadecimal

Converts a raw vector to one lower-case hexadecimal string, two digits per byte, with no separators and no prefix: the form sha256sum prints and most formats store. The conversion runs in C, so for a short digest it costs far less than the hash itself.

Usage

crypt_hex(x)

Arguments

x

A raw vector, at most 2^30 - 1 bytes long (a longer result would exceed R's limit on the length of a single string).

Value

A character vector of length one, 2 * length(x) characters long. crypt_hex(raw(0)) is "".

Details

Hex is an explicit step at the call site rather than an option on crypt_hash() and crypt_hmac(), so the digest functions return one type and a caller who wants text says so. It works on any bytes: a digest, a MAC, a key you need to print for a test.

See also

crypt_hash() and crypt_hmac(), whose results this is usually applied to.

Examples

crypt_hex(crypt_hash(charToRaw("abc")))
#> [1] "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"

crypt_hex(as.raw(c(0x00, 0x0f, 0xa0, 0xff)))
#> [1] "000fa0ff"

crypt_hex(raw(0))
#> [1] ""