Re: [PATCH 1/4] Add base64 encoder and decoder

> On Tue, Feb 9, 2010 at 1:09 PM, Hitoshi Mitake
> <mitake@dcl.info.waseda.ac.jp>  wrote:
>> +void base64_encode(char *out, const char *in, int inlen)
>> +{
>> +       const char *inp = in;
>> +       char *outp = out;
>
> ...Why? It's copying the pointers to pointers of identical type with
> different names, and never using the originals again... Looks like a
> sloppy extraction from another code-base to me.
>
>> +
>> +       while (inlen>= 3) {
>> +               *outp++ = base64char[(inp[0]>>  2)&  0x3f];
>> +               *outp++ = base64char[((inp[0]&  0x03)<<  4) |
>> +                                    ((inp[1]>>  4)&  0x0f)];
>> +               *outp++ = base64char[((inp[1]&  0x0f)<<  2) |
>> +                                    ((inp[2]>>  6)&  0x03)];
>> +               *outp++ = base64char[inp[2]&  0x3f];
>> +
>> +               inp += 3;
>> +               inlen -= 3;
>> +       }
>> +
>> +       if (inlen>  0) {
>> +               *outp++ = base64char[(inp[0]>>  2)&  0x3f];
>> +               if (inlen == 1) {
>> +                       *outp++ = base64char[(inp[0]&  0x03)<<  4];
>> +                       *outp++ = '=';
>> +               } else {
>> +                       *outp++ = base64char[((inp[0]&  0x03)<<  4) |
>> +                                            ((inp[1]>>  4)&  0x0f)];
>> +                       *outp++ = base64char[((inp[1]&  0x0f)<<  2)];
>> +               }
>> +               *outp++ = '=';
>> +       }
>> +
>> +       *outp = '\0';
>> +}
>
> If inlen is 0, a single '=' should be emitted (plus the obvious zero
> termination). It could be that the code deals with that by making sure
> that inlen never is zero, though.
>