diff options
Diffstat (limited to 'lexer.c')
| -rw-r--r-- | lexer.c | 229 |
1 files changed, 157 insertions, 72 deletions
@@ -322,6 +322,7 @@ parse_string(const char *buf, struct ut_op *op, struct ut_state *s) const char *in = buf; bool esc = false; int rem = sizeof(str) - 1; + int lead_surrogate = 0; int code; while (*in) { @@ -331,16 +332,48 @@ parse_string(const char *buf, struct ut_op *op, struct ut_state *s) if (in[0] == 'u') { if (isxdigit(in[1]) && isxdigit(in[2]) && isxdigit(in[3]) && isxdigit(in[4])) { - if (!utf8enc(&out, &rem, - hex(in[1]) * 16 * 16 * 16 + - hex(in[2]) * 16 * 16 + - hex(in[3]) * 16 + - hex(in[4]))) { + code = hex(in[1]) * 16 * 16 * 16 + + hex(in[2]) * 16 * 16 + + hex(in[3]) * 16 + + hex(in[4]); + + /* is a leading surrogate value */ + if ((code & 0xFC00) == 0xD800) { + /* found a subsequent leading surrogate, ignore and emit replacement char for previous one */ + if (lead_surrogate) { + if (!utf8enc(&out, &rem, 0xFFFD)) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } + } + + /* store surrogate value and advance to next escape sequence */ + lead_surrogate = code; + goto next; + } + + /* is a trailing surrogate value */ + else if ((code & 0xFC00) == 0xDC00) { + /* found a trailing surrogate following a leading one, combine and encode */ + if (lead_surrogate) { + code = 0x10000 + ((lead_surrogate & 0x3FF) << 10) + (code & 0x3FF); + lead_surrogate = 0; + } + + /* trailing surrogate not following a leading one, ignore and use replacement char */ + else { + code = 0xFFFD; + } + } + + if (!utf8enc(&out, &rem, code)) { s->off += (in - buf); return -UT_ERROR_OVERLONG_STRING; } +next: in += 5; } else { @@ -350,122 +383,174 @@ parse_string(const char *buf, struct ut_op *op, struct ut_state *s) } } - /* \xFF */ - else if (in[0] == 'x') { - if (isxdigit(in[1]) && isxdigit(in[2])) { - if (!utf8enc(&out, &rem, hex(in[1]) * 16 + hex(in[2]))) { + /* other escape sequences */ + else { + /* found any non-utf8 escape sequence following a leading unicode surrogate, + emit replacement character and skip surrogate. */ + if (lead_surrogate) { + if (!utf8enc(&out, &rem, 0xFFFD)) { s->off += (in - buf); return -UT_ERROR_OVERLONG_STRING; } - in += 3; - } - else { - s->off += (in - buf); - return -UT_ERROR_INVALID_ESCAPE; + lead_surrogate = 0; } - } - /* \377, \77 or \7 */ - else if (in[0] >= '0' && in[0] <= '7') { - /* \377 */ - if (in[1] >= '0' && in[1] <= '7' && - in[2] >= '0' && in[2] <= '7') { - code = dec(in[0]) * 8 * 8 + - dec(in[1]) * 8 + - dec(in[2]); + /* \xFF */ + if (in[0] == 'x') { + + + if (isxdigit(in[1]) && isxdigit(in[2])) { + if (!utf8enc(&out, &rem, hex(in[1]) * 16 + hex(in[2]))) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } - if (code > 255) { + in += 3; + } + else { s->off += (in - buf); return -UT_ERROR_INVALID_ESCAPE; } + } - if (!utf8enc(&out, &rem, code)) { - s->off += (in - buf); + /* \377, \77 or \7 */ + else if (in[0] >= '0' && in[0] <= '7') { + if (lead_surrogate) { + if (!utf8enc(&out, &rem, 0xFFFD)) { + s->off += (in - buf); - return -UT_ERROR_OVERLONG_STRING; + return -UT_ERROR_OVERLONG_STRING; + } + + lead_surrogate = 0; } - in += 3; - } + /* \377 */ + if (in[1] >= '0' && in[1] <= '7' && + in[2] >= '0' && in[2] <= '7') { + code = dec(in[0]) * 8 * 8 + + dec(in[1]) * 8 + + dec(in[2]); - /* \77 */ - else if (in[1] >= '0' && in[1] <= '7') { - if (!utf8enc(&out, &rem, dec(in[0]) * 8 + dec(in[1]))) { - s->off += (in - buf); + if (code > 255) { + s->off += (in - buf); - return -UT_ERROR_OVERLONG_STRING; + return -UT_ERROR_INVALID_ESCAPE; + } + + if (!utf8enc(&out, &rem, code)) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } + + in += 3; + } + + /* \77 */ + else if (in[1] >= '0' && in[1] <= '7') { + if (!utf8enc(&out, &rem, dec(in[0]) * 8 + dec(in[1]))) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } + + in += 2; } - in += 2; + /* \7 */ + else { + if (!utf8enc(&out, &rem, dec(in[0]))) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } + + in += 1; + } } - /* \7 */ + /* single character escape */ else { - if (!utf8enc(&out, &rem, dec(in[0]))) { - s->off += (in - buf); + if (lead_surrogate) { + if (!utf8enc(&out, &rem, 0xFFFD)) { + s->off += (in - buf); - return -UT_ERROR_OVERLONG_STRING; + return -UT_ERROR_OVERLONG_STRING; + } + + lead_surrogate = 0; } - in += 1; - } - } + if (rem-- < 1) { + s->off += (in - buf); - /* single character escape */ - else { - if (rem-- < 1) { - s->off += (in - buf); + return -UT_ERROR_OVERLONG_STRING; + } - return -UT_ERROR_OVERLONG_STRING; - } + switch (in[0]) { + case 'a': *out = '\a'; break; + case 'b': *out = '\b'; break; + case 'e': *out = '\e'; break; + case 'f': *out = '\f'; break; + case 'n': *out = '\n'; break; + case 'r': *out = '\r'; break; + case 't': *out = '\t'; break; + case 'v': *out = '\v'; break; + default: + *out = *in; + break; + } - switch (in[0]) { - case 'a': *out = '\a'; break; - case 'b': *out = '\b'; break; - case 'e': *out = '\e'; break; - case 'f': *out = '\f'; break; - case 'n': *out = '\n'; break; - case 'r': *out = '\r'; break; - case 't': *out = '\t'; break; - case 'v': *out = '\v'; break; - default: - *out = *in; - break; + in++; + out++; } - - in++; - out++; } esc = false; + continue; } /* begin of escape sequence */ - else if (*in == '\\') { + if (*in == '\\') { in++; esc = true; + continue; + } + + + /* there's a non-escape following a previous leading unicode surrogate, + * ignore surrogate and emit replacement char */ + if (lead_surrogate) { + if (!utf8enc(&out, &rem, 0xFFFD)) { + s->off += (in - buf); + + return -UT_ERROR_OVERLONG_STRING; + } + + lead_surrogate = 0; } + /* terminating quote */ - else if (*in == q) { + if (*in == q) { op->val = json_object_new_string_len(str, sizeof(str) - 1 - rem); return (in - buf) + 2; } /* ordinary char */ - else { - if (rem-- < 1) { - s->off += (in - buf); - - return -UT_ERROR_OVERLONG_STRING; - } + if (rem-- < 1) { + s->off += (in - buf); - *out++ = *in++; + return -UT_ERROR_OVERLONG_STRING; } + + *out++ = *in++; } return -UT_ERROR_UNTERMINATED_STRING; |