Re: [PATCH 2/2] hex: drop sha1_to_hex()

From: Junio C Hamano <gitster@pobox.com>
Date: Nov 12, 2019, 11:49 UTC
Message-ID: <xmqqimnpe2lj.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <20191112105759.GA9714@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 14 quoted lines

>>     @@ cache.h: int hex_to_bytes(unsigned char *binary, const char *hex, size_t len);
>>        * buffers, making it safe to make multiple calls for a single statement, like:
>>        *
>>      - *   printf("%s -> %s", sha1_to_hex(one), sha1_to_hex(two));
>>     -+ *   printf("%s -> %s", oid_to_hex(one), oid_to_hex(two));
>>     ++ *   printf("%s -> %s", hash_to_hex(one), hash_to_hex(two));
>>        */
>>       char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash, const struct git_hash_algo *);
>>       char *oid_to_hex_r(char *out, const struct object_id *oid);
>
> This one-liner leaves the types of "one" and "two" unspecified. :) So
> it's not wrong to use hash_to_hex(), but maybe it's better to be pushing
> people towards oid_to_hex() as their first choice? It probably doesn't
> matter too much either way.

The pre-context of that comment reads:

 * Convert a binary hash to its hex equivalent. The `_r` variant is reentrant,
 * and writes the NUL-terminated output to the buffer `out`, which must be at
 * least `GIT_MAX_HEXSZ + 1` bytes, and returns a pointer to out for
 * convenience.

so I think the intent of the example that used to use sha1_to_hex() has been the raw bytestring that is the object name, not its form that is encapsulated in the "struct object_id()".