An addendum to the previous email.
On 02/08/2017 16:30, Jan Tulak wrote:
On 29/07/2017 19:12, Luis R. Rodriguez wrote:
On Fri, Jul 28, 2017 at 04:45:58PM +0200, Jan Tulak wrote:
On 27/07/2017 18:27, Luis R. Rodriguez wrote:
On Thu, Jul 20, 2017 at 11:29:26AM +0200, Jan Tulak wrote:
diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index a69190b9..4b030101 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -107,6 +107,11 @@ unsigned int sectorsize;
* sets what is used with simple specifying the subopt (-d
file).
* A special SUBOPT_NEEDS_VAL can be used to require a
user-given
* value in any case.
+ *
+ * raw_input INTERNAL
+ * Filled raw string from the user, so we never lose that
information e.g.
+ * to print it back in case of an issue.
+ *
*/
struct opt_params {
const char name;
@@ -122,6 +127,7 @@ struct opt_params {
long long minval;
long long maxval;
long long defaultval;
+ const char *raw_input;
} subopt_params[MAX_SUBOPTS];
};
@@ -729,6 +735,18 @@ struct opt_params mopts = {
*/
#define WHACK_SIZE (128 * 1024)
+static inline void
+set_conf_raw(struct opt_params *opt, int subopt, const char *value)
+{
+ opt->subopt_params[subopt].raw_input = value;
+}
There are no bounds check on the array here, I think set_conf_raw()
should return int and we would check the return value. It could
return -EINVAL if the subopt is invalid for instance.
Good idea. The only issue is with the return code, that causes some
issues
when we are also returning values - I wanted the values to be turned
into
uint64. But do we need to return an error? I don't see what usecase
there
would be for it, other than detecting a bug. So an assert might be a
better
solution - then it can't happen that a wrong index is used and
result not
tested.
The setting of the value can be done by using an extra argument
pointer. Then
if its set it be assigned. Otherwise it would be left alone. The
return value
would return 0 on success, otherwise a standard return value
indicating the
cause of the error.
I strongly prefer to return the value, not an error code. We can do
the other way around, put the error code into an argument to get
roughly the same result, while constructions like set_conf_raw(FOO,
BAR, baz * get_conf_raw(FOO, BAR)) will continue to work without the
need for intermediate variables.
The *_raw functions are used on few places only, so it would be only a
small issue there, but for consistency, (get|set)_conf_val should have
the same behavior and an intermediate variable for every use of those
would be really annoying. So, how about this?
static inline void
set_conf_raw(struct opt_params *opt, int subopt, const char *value,
int *err)
{
if (subopt < 0 || subopt >= MAX_SUBOPTS) {
if (err != NULL) *err = EINVAL;
return;
}
opt->subopt_params[subopt].raw_input = value;
}
I just realized that there is probably no reason for set_conf_raw to
expect invalid subopt - that's clearly a bug and we should just print a
message and die, because who knows what happened... But for errors that
can arose from user input, the style presented above is still valid.
Jan
I don't think we need the too small or too big, a simple range issue
should
suffice and we have -ERANGE.
At this moment, we are telling if it is too small or too big, but when
there is no standard error code for that, ERANGE has to suffice.
Cheers,
Jan
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