Validate a single UTF-8 character according to RFC 3629.
| 47 | |
| 48 | // Validate a single UTF-8 character according to RFC 3629. |
| 49 | static int utf8proc_valid(const uint8_t *str, bufsize_t str_len) { |
| 50 | int length = utf8proc_utf8class[str[0]]; |
| 51 | |
| 52 | if (!length) |
| 53 | return -1; |
| 54 | |
| 55 | if ((bufsize_t)length > str_len) |
| 56 | return -str_len; |
| 57 | |
| 58 | switch (length) { |
| 59 | case 2: |
| 60 | if ((str[1] & 0xC0) != 0x80) |
| 61 | return -1; |
| 62 | if (str[0] < 0xC2) { |
| 63 | // Overlong |
| 64 | return -length; |
| 65 | } |
| 66 | break; |
| 67 | |
| 68 | case 3: |
| 69 | if ((str[1] & 0xC0) != 0x80) |
| 70 | return -1; |
| 71 | if ((str[2] & 0xC0) != 0x80) |
| 72 | return -2; |
| 73 | if (str[0] == 0xE0) { |
| 74 | if (str[1] < 0xA0) { |
| 75 | // Overlong |
| 76 | return -length; |
| 77 | } |
| 78 | } else if (str[0] == 0xED) { |
| 79 | if (str[1] >= 0xA0) { |
| 80 | // Surrogate |
| 81 | return -length; |
| 82 | } |
| 83 | } |
| 84 | break; |
| 85 | |
| 86 | case 4: |
| 87 | if ((str[1] & 0xC0) != 0x80) |
| 88 | return -1; |
| 89 | if ((str[2] & 0xC0) != 0x80) |
| 90 | return -2; |
| 91 | if ((str[3] & 0xC0) != 0x80) |
| 92 | return -3; |
| 93 | if (str[0] == 0xF0) { |
| 94 | if (str[1] < 0x90) { |
| 95 | // Overlong |
| 96 | return -length; |
| 97 | } |
| 98 | } else if (str[0] >= 0xF4) { |
| 99 | if (str[0] > 0xF4 || str[1] >= 0x90) { |
| 100 | // Above 0x10FFFF |
| 101 | return -length; |
| 102 | } |
| 103 | } |
| 104 | break; |
| 105 | } |
| 106 |
no outgoing calls
no test coverage detected