[Ocfs2-tools-devel] [PATCH 28/39] mkfs.ocfs2: Add the cluster stack options.

[Joel Becker]

On Fri, May 23, 2008 at 05:14:11PM -0700, Sunil Mushran wrote:
>> +static int pick_one(State *s, const char *what_is_it,
>> +		    const char *user_value, const char *o2cb_value,
>> +		    const char *disk_value, char **ret_value)
>> +{
>> +	int rc = -1;
>> +
>> +	/*
>> +	 * First, compare o2cb and disk values.  If we get past this
>> +	 * block (via match or override), the o2cb value takes precedence.
>> +	 */
>> +	if (disk_value) {
>> +		if (o2cb_value) {
>> +			if (strcmp(o2cb_value, disk_value)) {
>> +				fprintf(stderr,
>> +					"%s is configured to use %s \"%s\", but \"%s\" is currently running.\n"
>> +					"%s will not be able to determine if the filesystem is in use.\n",
>> +					s->device_name, what_is_it,
>> +					disk_value, o2cb_value,
>> +					s->progname);
>> +				if (!s->force) {
>> +					fprintf(stderr,
>> +						"To skip this check, use --force or -F\n");
>> +					goto out;
>> +				}
>> +				fprintf(stdout,
>> +					"Overwrite of disk information forced\n");
>> +			}
>> +		}
>> +	}
>> +
>> +	if (user_value) {
>> +		if (o2cb_value) {
>> +			if (strcmp(o2cb_value, user_value)) {
>> +				fprintf(stderr, "%s \"%s\" was requested, but \"%s\" is running.\n",
>> +				what_is_it, user_value, o2cb_value);
>> +				if (!s->force) {
>> +					fprintf(stderr,
>> +						"To skip this check, use --force or -F\n");
>> +					goto out;
>> +				}
>> +				fprintf(stdout, "%s forced\n", what_is_it);
>> +			}
>> +		} else if (disk_value) {
>> +			if (strcmp(disk_value, user_value)) {
>> +				fprintf(stderr, "%s \"%s\" was requested, but %s is configured for \"%s\".\n",
>> +					what_is_it, user_value,
>> +					s->device_name, disk_value);
>> +				if (!s->force) {
>> +					fprintf(stderr,
>> +						"To skip this check, use --force or -F\n");
>> +					goto out;
>> +				}
>> +				fprintf(stderr, "%s forced\n", what_is_it);
>> +			}
>> +		}
>> +		*ret_value = strdup(user_value);
>> +	} else if (o2cb_value)
>> +		*ret_value = strdup(o2cb_value);
>> +	else if (disk_value)
>> +		*ret_value = strdup(disk_value);
>> +
>> +	rc = 0;
>> +
>> +out:
>> +	return rc;;
>> +}
>>   
>
> Wondering if we can simplify this.

	Nope.  It's dealing with the multitude of sources for these
values:

1. The command line
2. The physical disk
3. The running configuration

	This code encodes an order of precedence for these sources.
Mark and I had a long discussion about it when I first wrote it.

Joel

-- 

"Baby, even the losers
 Get luck sometimes.
 Even the losers
 Keep a little bit of pride."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127