1 /* $NetBSD: valid_utf8_string.c,v 1.3 2025/02/25 19:15:52 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* valid_utf8_string 3 6 /* SUMMARY 7 /* predicate if string is valid UTF-8 8 /* SYNOPSIS 9 /* #include <stringops.h> 10 /* 11 /* int valid_utf8_string(str, len) 12 /* const char *str; 13 /* ssize_t len; 14 /* 15 /* int valid_utf8_stringz(str) 16 /* const char *str; 17 /* ssize_t len; 18 /* DESCRIPTION 19 /* valid_utf8_string() determines if all bytes in a string 20 /* satisfy parse_utf8_char(3h) checks. See there for any 21 /* implementation limitations. 22 /* 23 /* valid_utf8_stringz() determines the same for zero-terminated 24 /* strings. 25 /* 26 /* A zero-length string is considered valid. 27 /* DIAGNOSTICS 28 /* The result value is zero when the caller specifies a negative 29 /* length, or a string that does not pass parse_utf8_char(3h) checks. 30 /* SEE ALSO 31 /* parse_utf8_char(3h), parse one UTF-8 multibyte character 32 /* LICENSE 33 /* .ad 34 /* .fi 35 /* The Secure Mailer license must be distributed with this software. 36 /* AUTHOR(S) 37 /* Wietse Venema 38 /* IBM T.J. Watson Research 39 /* P.O. Box 704 40 /* Yorktown Heights, NY 10598, USA 41 /* 42 /* Wietse Venema 43 /* porcupine.org 44 /* Amawalk, NY 10501, USA 45 /*--*/ 46 47 /* System library. */ 48 49 #include <sys_defs.h> 50 51 /* Utility library. */ 52 53 #include <stringops.h> 54 #include <parse_utf8_char.h> 55 56 /* valid_utf8_string - validate string according to RFC 3629 */ 57 58 int valid_utf8_string(const char *str, ssize_t len) 59 { 60 const char *ep = str + len; 61 const char *cp; 62 const char *last; 63 64 if (len < 0) 65 return (0); 66 if (len == 0) 67 return (1); 68 69 /* 70 * Ideally, the compiler will inline parse_utf8_char(). 71 */ 72 for (cp = str; cp < ep; cp++) { 73 if ((last = parse_utf8_char(cp, ep)) != 0) 74 cp = last; 75 else 76 return (0); 77 } 78 return (1); 79 } 80 81 /* valid_utf8_stringz - validate string according to RFC 3629 */ 82 83 int valid_utf8_stringz(const char *str) 84 { 85 const char *cp; 86 const char *last; 87 88 /* 89 * Ideally, the compiler will inline parse_utf8_char(), propagate the 90 * null pointer constant value, and eliminate code branches that test 91 * whether 0 != 0. 92 */ 93 for (cp = str; *cp; cp++) { 94 if ((last = parse_utf8_char(cp, 0)) != 0) 95 cp = last; 96 else 97 return (0); 98 } 99 return (1); 100 } 101 102 /* 103 * Stand-alone test program. Each string is a line without line terminator. 104 */ 105 #ifdef TEST 106 #include <stdlib.h> 107 #include <string.h> 108 #include <msg.h> 109 #include <vstream.h> 110 #include <msg_vstream.h> 111 112 /* 113 * Test cases for 1-, 2-, and 3-byte encodings. See printable.c for UTF8 114 * parser resychronization tests. 115 * 116 * XXX Need a test for 4-byte encodings, preferably with strings that can be 117 * displayed. 118 * 119 * XXX Need tests with hand-crafted over-long encodings and surrogates. 120 */ 121 struct testcase { 122 const char *name; 123 const char *input; 124 int expected; 125 }; 126 127 #define T_VALID (1) 128 #define T_INVALID (0) 129 #define valid_to_str(v) ((v) ? "VALID" : "INVALID") 130 131 static const struct testcase testcases[] = { 132 {"Printable ASCII", 133 "printable", T_VALID, 134 }, 135 {"Latin script, accented, no error", 136 "na\303\257ve", T_VALID, 137 }, 138 {"Latin script, accented, missing non-leading byte", 139 "na\303ve", T_INVALID, 140 }, 141 {"Latin script, accented, missing leading byte", 142 "na\257ve", T_INVALID, 143 }, 144 {"Viktor, Cyrillic, no error", 145 "\320\262\320\270\320\272\321\202\320\276\321\200", T_VALID, 146 }, 147 {"Viktor, Cyrillic, missing non-leading byte", 148 "\320\262\320\320\272\321\202\320\276\321\200", T_INVALID, 149 }, 150 {"Viktor, Cyrillic, missing leading byte", 151 "\320\262\270\320\272\321\202\320\276\321\200", T_INVALID, 152 }, 153 {"Viktor, Cyrillic, truncated", 154 "\320\262\320\270\320\272\321\202\320\276\321", T_INVALID, 155 }, 156 {"Viktor, Hebrew, no error", 157 "\327\225\327\231\327\247\327\230\327\225\326\274\327\250", T_VALID, 158 }, 159 {"Viktor, Hebrew, missing leading byte", 160 "\327\225\231\327\247\327\230\327\225\326\274\327\250", T_INVALID, 161 }, 162 {"Chinese (Simplified), no error", 163 "\344\270\255\345\233\275\344\272\222\350\201\224\347\275\221\347" 164 "\273\234\345\217\221\345\261\225\347\212\266\345\206\265\347\273" 165 "\237\350\256\241\346\212\245\345\221\212", T_VALID, 166 }, 167 {"Chinese (Simplified), missing leading byte", 168 "\344\270\255\345\233\275\344\272\222\350\201\224\275\221\347" 169 "\273\234\345\217\221\345\261\225\347\212\266\345\206\265\347\273" 170 "\237\350\256\241\346\212\245\345\221\212", T_INVALID, 171 }, 172 {"Chinese (Simplified), missing first non-leading byte", 173 "\344\270\255\345\233\275\344\272\222\350\201\224\347\221\347" 174 "\273\234\345\217\221\345\261\225\347\212\266\345\206\265\347\273" 175 "\237\350\256\241\346\212\245\345\221\212", T_INVALID, 176 }, 177 {"Chinese (Simplified), missing second non-leading byte", 178 "\344\270\255\345\233\275\344\272\222\350\201\224\347\275\347" 179 "\273\234\345\217\221\345\261\225\347\212\266\345\206\265\347\273" 180 "\237\350\256\241\346\212\245\345\221\212", T_INVALID, 181 }, 182 {"Chinese (Simplified), truncated", 183 "\344\270\255\345\233\275\344\272\222\350\201\224\347\275\221\347" 184 "\273\234\345\217\221\345\261\225\347\212\266\345\206\265\347\273" 185 "\237\350\256\241\346\212\245\345", T_INVALID, 186 }, 187 }; 188 189 int main(int argc, char **argv) 190 { 191 const struct testcase *tp; 192 int pass; 193 int fail; 194 195 #define NUM_TESTS sizeof(testcases)/sizeof(testcases[0]) 196 197 msg_vstream_init(basename(argv[0]), VSTREAM_ERR); 198 util_utf8_enable = 1; 199 200 for (pass = fail = 0, tp = testcases; tp < testcases + NUM_TESTS; tp++) { 201 int actual_l; 202 int actual_z; 203 int ok = 0; 204 205 /* 206 * Notes: 207 * 208 * - The msg(3) functions use printable() which interferes when logging 209 * inputs and outputs. Use vstream_fprintf() instead. 210 */ 211 vstream_fprintf(VSTREAM_ERR, "RUN %s\n", tp->name); 212 actual_l = valid_utf8_string(tp->input, strlen(tp->input)); 213 actual_z = valid_utf8_stringz(tp->input); 214 215 if (actual_l != tp->expected) { 216 vstream_fprintf(VSTREAM_ERR, 217 "input: >%s<, 'actual_l' got: >%s<, want: >%s<\n", 218 tp->input, valid_to_str(actual_l), 219 valid_to_str(tp->expected)); 220 } else if (actual_z != tp->expected) { 221 vstream_fprintf(VSTREAM_ERR, 222 "input: >%s<, 'actual_z' got: >%s<, want: >%s<\n", 223 tp->input, valid_to_str(actual_z), 224 valid_to_str(tp->expected)); 225 } else { 226 vstream_fprintf(VSTREAM_ERR, "input: >%s<, got and want: >%s<\n", 227 tp->input, valid_to_str(actual_l)); 228 ok = 1; 229 } 230 if (ok) { 231 vstream_fprintf(VSTREAM_ERR, "PASS %s\n", tp->name); 232 pass++; 233 } else { 234 vstream_fprintf(VSTREAM_ERR, "FAIL %s\n", tp->name); 235 fail++; 236 } 237 } 238 msg_info("PASS=%d FAIL=%d", pass, fail); 239 return (fail > 0); 240 } 241 242 #endif 243
Indexes created Wed Sep 30 00:29:25 UTC 2026