[PATCH 19/19] mkfs: add optional 'reason' for illegal_option

[jtulak at redhat.com]

From: Jan Tulak <jtulak at redhat.com>

Allow us to tell the user what exactly is wrong with his options.
For example, that the value is too small, instead of just generic
"bad option."

Signed-off-by: Jan Tulak <jtulak at redhat.com>
---
 mkfs/xfs_mkfs.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 680c6c4..76e193d 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -1550,11 +1550,18 @@ static __attribute__((noreturn)) void
 illegal_option(
 	const char	*value,
 	struct opt_params	*opts,
-	int		index)
+	int		index,
+	const char *reason)
 {
-	fprintf(stderr,
-		_("Illegal value %s for -%c %s option\n"),
-		value, opts->name, opts->subopts[index]);
+	if(reason == NULL){
+		fprintf(stderr,
+			_("Illegal value %s for -%c %s option\n"),
+			value, opts->name, opts->subopts[index]);
+	} else {
+		fprintf(stderr,
+			_("Illegal value %s for -%c %s option: %s\n"),
+			value, opts->name, opts->subopts[index], reason);
+	}
 	usage();
 }

@@ -1646,16 +1653,18 @@ getnum(

 		c = strtoll(str, &str_end, 0);
 		if (c == 0 && str_end == str)
-			illegal_option(str, opts, index);
+			illegal_option(str, opts, index, NULL);
 		if (*str_end != '\0')
-			illegal_option(str, opts, index);
+			illegal_option(str, opts, index, NULL);
 	}

 	/* Validity check the result. */
-	if (c < sp->minval || c > sp->maxval)
-		illegal_option(str, opts, index);
+	if (c < sp->minval)
+		illegal_option(str, opts, index, "value is too small");
+	else if (c > sp->maxval)
+		illegal_option(str, opts, index, "value is too large");
 	if (sp->is_power_2 && !ispow2(c))
-		illegal_option(str, opts, index);
+		illegal_option(str, opts, index, "value has to be power of 2");
 	return c;
 }

--
2.6.0