On Mon, Jul 12, 2021 at 07:55:37AM -0400, Jeff Layton wrote: > On Sun, 2021-07-11 at 12:40 -0500, Eric Biggers wrote: > > Some nits about comments: > > > > On Fri, Jun 25, 2021 at 09:58:12AM -0400, Jeff Layton wrote: > > > diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c > > > index 6ca7d16593ff..32b1f50433ba 100644 > > > --- a/fs/crypto/fname.c > > > +++ b/fs/crypto/fname.c > > > @@ -178,10 +178,8 @@ static int fname_decrypt(const struct inode *inode, > > > static const char lookup_table[65] = > > > "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,"; > > > > > > -#define BASE64_CHARS(nbytes) DIV_ROUND_UP((nbytes) * 4, 3) > > > - > > > /** > > > - * base64_encode() - base64-encode some bytes > > > + * fscrypt_base64_encode() - base64-encode some bytes > > > * @src: the bytes to encode > > > * @len: number of bytes to encode > > > * @dst: (output) the base64-encoded string. Not NUL-terminated. > > > * > > > * Encodes the input string using characters from the set [A-Za-z0-9+,]. > > > * The encoded string is roughly 4/3 times the size of the input string. > > > * > > > * Return: length of the encoded string > > > */ > > > -static int base64_encode(const u8 *src, int len, char *dst) > > > +int fscrypt_base64_encode(const u8 *src, int len, char *dst) > > > > As this function will be used more widely, this comment should be fixed to be > > more precise. "Roughly 4/3" isn't precise; it's actually exactly > > FSCRYPT_BASE64_CHARS(len), right? The following would be better: > > > > * Encode the input bytes using characters from the set [A-Za-z0-9+,]. > > * > > * Return: length of the encoded string. This will be equal to > > * FSCRYPT_BASE64_CHARS(len). > > > > I'm not certain, but I thought that FSCRYPT_BASE64_CHARS gave you a > worst-case estimate of the inflation. This returns the actual length of > the resulting encoded string, which may be less than > FSCRYPT_BASE64_CHARS(len). > As far as I can tell, it's the exact amount. - Eric
