diff options
| -rw-r--r-- | src/pugixml.cpp | 91 |
1 files changed, 82 insertions, 9 deletions
diff --git a/src/pugixml.cpp b/src/pugixml.cpp index fc48701..c92e66e 100644 --- a/src/pugixml.cpp +++ b/src/pugixml.cpp @@ -1895,8 +1895,67 @@ PUGI__NS_BEGIN return is_little_endian() ? encoding_utf32_le : encoding_utf32_be; } - PUGI__FN xml_encoding guess_buffer_encoding(uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3) + PUGI__FN bool parse_declaration_encoding(const uint8_t* data, size_t size, const uint8_t** out_encoding, size_t* out_length) { + #define PUGI__SCANCHAR(ch) { if (offset >= size || data[offset] != ch) return false; offset++; } + #define PUGI__SCANCHARTYPE(ct) { while (offset < size && PUGI__IS_CHARTYPE(data[offset], ct)) offset++; } + + // check if we have a non-empty XML declaration + if (size < 6 || !((data[0] == '<') & (data[1] == '?') & (data[2] == 'x') & (data[3] == 'm') & (data[4] == 'l') && PUGI__IS_CHARTYPE(data[5], ct_space))) + return false; + + // scan XML declaration until the encoding field + for (size_t i = 6; i + 1 < size; ++i) + { + // declaration can not contain ? in quoted values + if (data[i] == '?') + return false; + + if (data[i] == 'e' && data[i + 1] == 'n') + { + size_t offset = i; + + // encoding follows the version field which can't contain 'en' so this has to be the encoding if XML is well formed + PUGI__SCANCHAR('e'); PUGI__SCANCHAR('n'); PUGI__SCANCHAR('c'); PUGI__SCANCHAR('o'); + PUGI__SCANCHAR('d'); PUGI__SCANCHAR('i'); PUGI__SCANCHAR('n'); PUGI__SCANCHAR('g'); + + // S? = S? + PUGI__SCANCHARTYPE(ct_space); + PUGI__SCANCHAR('='); + PUGI__SCANCHARTYPE(ct_space); + + // the only two valid delimiters are ' and " + uint8_t delimiter = (offset < size && data[offset] == '"') ? '"' : '\''; + + PUGI__SCANCHAR(delimiter); + + size_t start = offset; + + *out_encoding = data + offset; + + PUGI__SCANCHARTYPE(ct_symbol); + + *out_length = offset - start; + + PUGI__SCANCHAR(delimiter); + + return true; + } + } + + return false; + + #undef PUGI__SCANCHAR + #undef PUGI__SCANCHARTYPE + } + + PUGI__FN xml_encoding guess_buffer_encoding(const uint8_t* data, size_t size) + { + // skip encoding autodetection if input buffer is too small + if (size < 4) return encoding_utf8; + + uint8_t d0 = data[0], d1 = data[1], d2 = data[2], d3 = data[3]; + // look for BOM in first few bytes if (d0 == 0 && d1 == 0 && d2 == 0xfe && d3 == 0xff) return encoding_utf32_be; if (d0 == 0xff && d1 == 0xfe && d2 == 0 && d3 == 0) return encoding_utf32_le; @@ -1909,13 +1968,32 @@ PUGI__NS_BEGIN if (d0 == 0x3c && d1 == 0 && d2 == 0 && d3 == 0) return encoding_utf32_le; if (d0 == 0 && d1 == 0x3c && d2 == 0 && d3 == 0x3f) return encoding_utf16_be; if (d0 == 0x3c && d1 == 0 && d2 == 0x3f && d3 == 0) return encoding_utf16_le; - if (d0 == 0x3c && d1 == 0x3f && d2 == 0x78 && d3 == 0x6d) return encoding_utf8; // look for utf16 < followed by node name (this may fail, but is better than utf8 since it's zero terminated so early) if (d0 == 0 && d1 == 0x3c) return encoding_utf16_be; if (d0 == 0x3c && d1 == 0) return encoding_utf16_le; - // no known BOM detected, assume utf8 + // no known BOM detected; parse declaration + const uint8_t* enc = 0; + size_t enc_length = 0; + + if (d0 == 0x3c && d1 == 0x3f && d2 == 0x78 && d3 == 0x6d && parse_declaration_encoding(data, size, &enc, &enc_length)) + { + // iso-8859-1 (case-insensitive) + if (enc_length == 10 + && (enc[0] | ' ') == 'i' && (enc[1] | ' ') == 's' && (enc[2] | ' ') == 'o' + && enc[3] == '-' && enc[4] == '8' && enc[5] == '8' && enc[6] == '5' && enc[7] == '9' + && enc[8] == '-' && enc[9] == '1') + return encoding_latin1; + + // latin1 (case-insensitive) + if (enc_length == 6 + && (enc[0] | ' ') == 'l' && (enc[1] | ' ') == 'a' && (enc[2] | ' ') == 't' + && (enc[3] | ' ') == 'i' && (enc[4] | ' ') == 'n' + && enc[5] == '1') + return encoding_latin1; + } + return encoding_utf8; } @@ -1933,15 +2011,10 @@ PUGI__NS_BEGIN // only do autodetection if no explicit encoding is requested if (encoding != encoding_auto) return encoding; - // skip encoding autodetection if input buffer is too small - if (size < 4) return encoding_utf8; - // try to guess encoding (based on XML specification, Appendix F.1) const uint8_t* data = static_cast<const uint8_t*>(contents); - PUGI__DMC_VOLATILE uint8_t d0 = data[0], d1 = data[1], d2 = data[2], d3 = data[3]; - - return guess_buffer_encoding(d0, d1, d2, d3); + return guess_buffer_encoding(data, size); } PUGI__FN bool get_mutable_buffer(char_t*& out_buffer, size_t& out_length, const void* contents, size_t size, bool is_mutable) |