Subject: Re: [PATCH v6 1/4] sha1_file.c: support reading from a loose object of unknown type

From: Junio C Hamano <[email-masked]>
Date: Thu, 02 Apr 2015 12:12:34 -0700

Karthik Nayak <[email-masked]> writes:

> +static int unpack_sha1_header_to_strbuf(git_zstream *stream, unsigned char *map,
> +					unsigned long mapsize,
> +					struct strbuf *header)
> +{
> +	unsigned char buffer[32], *cp;
> +	unsigned long bufsiz = sizeof(buffer);
> +	int status;
> +
> +	status = unpack_sha1_header(stream, map, mapsize, buffer, bufsiz);

I briefly wondered if this can return Z_BUF_ERROR, but it is OK
because we do not call inflate with Z_FINISH in unpack_sha1_header()
for obvious reasons ;-)

> +	if (status) {
> +		strbuf_add(header, buffer, stream->next_out - buffer);
> +		return status;
> +	}

> +	do {
> +		status = git_inflate(stream, 0);
> +		strbuf_add(header, buffer, stream->next_out - buffer);
> +		for (cp = buffer; cp < stream->next_out; cp++)
> +			if (!*cp)
> +				/* Found the NUL at the end of the header */
> +				return 0;
> +		stream->next_out = buffer;
> +		stream->avail_out = bufsiz;
> +	} while (status != Z_STREAM_END);
> +	return -1;
> +}

OK.

> @@ -1614,27 +1642,24 @@ static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long s
>   * too permissive for what we want to check. So do an anal
>   * object header parse by hand.
>   */
> -int parse_sha1_header(const char *hdr, unsigned long *sizep)
> +int parse_sha1_header_extended(const char *hdr, struct object_info *oi,
> +			       unsigned int flags)
>  {
> -	char type[10];
> -	int i;
> +	struct strbuf typename = STRBUF_INIT;
>  	unsigned long size;
> +	int type;
>  
>  	/*
>  	 * The type can be at most ten bytes (including the

Is this still a valid comment?

>  	 * terminating '\0' that we add), and is followed by
>  	 * a space.
>  	 */
> -	i = 0;
>  	for (;;) {
>  		char c = *hdr++;
>  		if (c == ' ')
>  			break;
> -		type[i++] = c;
> -		if (i >= sizeof(type))
> -			return -1;
> +		strbuf_addch(&typename, c);
>  	}
> -	type[i] = 0;
>  
>  	/*
>  	 * The length must follow immediately, and be in canonical