checkpatch: prefer kstrto<foo> to sscanf(buf, "%<lhuidx>", &bar);

Use the kstrto<foo> functions in preference to sscanf.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -4314,6 +4314,27 @@ sub process {
 			     "unchecked sscanf return value\n" . "$here\n$stat_real\n");
 		}
 
+# check for simple sscanf that should be kstrto<foo>
+		if ($^V && $^V ge 5.10.0 &&
+		    defined $stat &&
+		    $line =~ /\bsscanf\b/) {
+			my $lc = $stat =~ tr@\n@@;
+			$lc = $lc + $linenr;
+			my $stat_real = raw_line($linenr, 0);
+		        for (my $count = $linenr + 1; $count <= $lc; $count++) {
+				$stat_real = $stat_real . "\n" . raw_line($count, 0);
+			}
+			if ($stat_real =~ /\bsscanf\b\s*\(\s*$FuncArg\s*,\s*("[^"]+")/) {
+				my $format = $6;
+				my $count = $format =~ tr@%@%@;
+				if ($count == 1 &&
+				    $format =~ /^"\%(?i:ll[udxi]|[udxi]ll|ll|[hl]h?[udxi]|[udxi][hl]h?|[hl]h?|[udxi])"$/) {
+					WARN("SSCANF_TO_KSTRTO",
+					     "Prefer kstrto<type> to single variable sscanf\n" . "$here\n$stat_real\n");
+				}
+			}
+		}
+
 # check for new externs in .h files.
 		if ($realfile =~ /\.h$/ &&
 		    $line =~ /^\+\s*(extern\s+)$Type\s*$Ident\s*\(/s) {