sodium_memcmp() function can be used for this purpose.0 if the len bytes pointed to by b1_ match the len bytes pointed to by b2_. Otherwise, it returns -1.sodium_memcmp() is not a lexicographic comparator and is not a generic replacement for memcmp().sodium_bin2hex() function converts bin_len bytes stored at bin into a hexadecimal string.hex and includes a nul byte (\0) terminator.hex_maxlen is the maximum number of bytes that the function is allowed to write starting at hex. It must be at least bin_len * 2 + 1 bytes.hex. It evaluates in constant time for a given size.sodium_hex2bin() function parses a hexadecimal string hex and converts it to a byte sequence.hex does not have to be nul terminated, as the number of characters to parse is supplied via the hex_len parameter.ignore is a string of characters to skip. For example, the string ": " allows colons and spaces to be present at any location in the hexadecimal string. These characters will just be ignored. As a result, "69:FC", "69 FC", "69 : FC" and "69FC" will be valid inputs and produce the same output.ignore can be set to NULL to disallow any non-hexadecimal character.bin_maxlen is the maximum number of bytes to put into bin.bin_maxlen bytes have been written.hex_end is not NULL, it will be set to the address of the first byte after the last valid parsed character.0 on success.-1 if more than bin_maxlen bytes would be required to store the parsed string or the string couldn't be fully parsed, but a valid pointer for hex_end was not provided.sodium_bin2base64() function encodes bin as a Base64 string. variant must be one of:sodium_base64_VARIANT_ORIGINALsodium_base64_VARIANT_ORIGINAL_NO_PADDINGsodium_base64_VARIANT_URLSAFEsodium_base64_VARIANT_URLSAFE_NO_PADDINGb64_maxlen is not straightforward and depends on the chosen variant.sodium_base64_ENCODED_LEN(BIN_LEN, VARIANT) macro returns the minimum number of bytes required to encode BIN_LEN bytes using the Base64 variant VARIANT. The returned length includes a trailing \0 byte.sodium_base64_encoded_len(size_t bin_len, int variant) function is also available for the same purpose.sodium_base642bin() function decodes a Base64 string using the given variant and an optional set of characters to ignore (typically: whitespaces and newlines).b64_end is not NULL, it will be set to the address of the first byte after the last valid parsed character.b64_len string will always be at most b64_len / 4 * 3 bytes long.0 on success.-1 if more than bin_maxlen bytes would be required to store the parsed string or the string couldn't be fully parsed, but a valid pointer for b64_end was not provided.sodium_increment() function takes a pointer to an arbitrary-long unsigned number and increments it.sodium_increment() can be used to increment nonces in constant time.sodium_add() function accepts two pointers to unsigned numbers encoded in little-endian format, a and b, both of size len bytes.(a + b) mod 2^(8*len) in constant time for a given length and overwrites a with the result.sodium_sub() function accepts two pointers to unsigned numbers encoded in little-endian format, a and b, both of size len bytes.(a - b) mod 2^(8*len) in constant time for a given length and overwrites a with the result.b1_ and b2_, two len bytes numbers encoded in little-endian format, this function returns:-1 if b1_ is less than b2_0 if b1_ equals b2_1 if b1_ is greater than b2_1 if the nlen bytes vector pointed by n contains only zeros. It returns 0 if non-zero bits are found.sodium_stackzero() function clears len bytes above the current stack pointer, to overwrite sensitive values that may have been temporarily stored on the stack.sodium_base64_VARIANT_*() macros don't have associated symbols. Bindings are encouraged to define specialized encoding/decoding functions instead.