author: Jessica Yu <jeyu@redhat.com> 2016-03-17 14:23:07 -0700
committer: Linus Torvalds <torvalds@linux-foundation.org> 2016-03-17 15:09:34 -0700
commit: f9310b2f9a19b7f16c7b1c1558f8b649b9b933c1
parent: 2553b67a1fbe7bf202e4e8070ab0b00d3d3a06a2
Commit Summary:
Diffstat:
1 file changed, 51 insertions, 1 deletion
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 525c8e19bda2..ccb664b54280 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -2640,8 +2640,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
if (*fmt == '*') {
if (!*str)
break;
- while (!isspace(*fmt) && *fmt != '%' && *fmt)
+ while (!isspace(*fmt) && *fmt != '%' && *fmt) {
+ /* '%*[' not yet supported, invalid format */
+ if (*fmt == '[')
+ return num;
fmt++;
+ }
while (!isspace(*str) && *str)
str++;
continue;
@@ -2714,6 +2718,59 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
num++;
}
continue;
+ /*
+ * Warning: This implementation of the '[' conversion specifier
+ * deviates from its glibc counterpart in the following ways:
+ * (1) It does NOT support ranges i.e. '-' is NOT a special
+ * character
+ * (2) It cannot match the closing bracket ']' itself
+ * (3) A field width is required
+ * (4) '%*[' (discard matching input) is currently not supported
+ *
+ * Example usage:
+ * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
+ * buf1, buf2, buf3);
+ * if (ret < 3)
+ * // etc..
+ */
+ case '[':
+ {
+ char *s = (char *)va_arg(args, char *);
+ DECLARE_BITMAP(set, 256) = {0};
+ unsigned int len = 0;
+ bool negate = (*fmt == '^');
+
+ /* field width is required */
+ if (field_width == -1)
+ return num;
+
+ if (negate)
+ ++fmt;
+
+ for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
+ set_bit((u8)*fmt, set);
+
+ /* no ']' or no character set found */
+ if (!*fmt || !len)
+ return num;
+ ++fmt;
+
+ if (negate) {
+ bitmap_complement(set, set, 256);
+ /* exclude null '\0' byte */
+ clear_bit(0, set);
+ }
+
+ /* match must be non-empty */
+ if (!test_bit((u8)*str, set))
+ return num;
+
+ while (test_bit((u8)*str, set) && field_width--)
+ *s++ = *str++;
+ *s = '\0';
+ ++num;
+ }
+ continue;
case 'o':
base = 8;
break;