diff options
| -rw-r--r-- | lib/vsprintf.c | 59 |
1 files changed, 58 insertions, 1 deletions
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; |