diff options
Diffstat (limited to 'ext/json/ext/parser/unicode.c')
| -rw-r--r-- | ext/json/ext/parser/unicode.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/ext/json/ext/parser/unicode.c b/ext/json/ext/parser/unicode.c new file mode 100644 index 0000000000..609a0e83e2 --- /dev/null +++ b/ext/json/ext/parser/unicode.c @@ -0,0 +1,156 @@ +/* vim: set cin et sw=4 ts=4: */ + +#include "unicode.h" + +/* + * Copyright 2001-2004 Unicode, Inc. + * + * Disclaimer + * + * This source code is provided as is by Unicode, Inc. No claims are + * made as to fitness for any particular purpose. No warranties of any + * kind are expressed or implied. The recipient agrees to determine + * applicability of information provided. If this file has been + * purchased on magnetic or optical media from Unicode, Inc., the + * sole remedy for any claim will be exchange of defective media + * within 90 days of receipt. + * + * Limitations on Rights to Redistribute This Code + * + * Unicode, Inc. hereby grants the right to freely use the information + * supplied in this file in the creation of products supporting the + * Unicode Standard, and to make copies of this file in any form + * for internal or external distribution as long as this notice + * remains attached. + */ + +/* + * Index into the table below with the first byte of a UTF-8 sequence to + * get the number of trailing bytes that are supposed to follow it. + * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is + * left as-is for anyone who may want to do such conversion, which was + * allowed in earlier algorithms. + */ +static const char trailingBytesForUTF8[256] = { + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, + 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 +}; + +/* + * Magic values subtracted from a buffer value during UTF8 conversion. + * This table contains as many values as there might be trailing bytes + * in a UTF-8 sequence. + */ +static const UTF32 offsetsFromUTF8[6] = { 0x00000000UL, 0x00003080UL, 0x000E2080UL, + 0x03C82080UL, 0xFA082080UL, 0x82082080UL }; + +/* + * Once the bits are split out into bytes of UTF-8, this is a mask OR-ed + * into the first byte, depending on how many bytes follow. There are + * as many entries in this table as there are UTF-8 sequence types. + * (I.e., one byte sequence, two byte... etc.). Remember that sequencs + * for *legal* UTF-8 will be 4 or fewer bytes total. + */ +static const UTF8 firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC }; + +char *JSON_convert_UTF16_to_UTF8 ( + VALUE buffer, + char *source, + char *sourceEnd, + ConversionFlags flags) +{ + UTF16 *tmp, *tmpPtr, *tmpEnd; + char buf[5]; + long n = 0, i; + char *p = source - 1; + + while (p < sourceEnd && p[0] == '\\' && p[1] == 'u') { + p += 6; + n++; + } + p = source + 1; + buf[4] = 0; + tmpPtr = tmp = ALLOC_N(UTF16, n); + tmpEnd = tmp + n; + for (i = 0; i < n; i++) { + buf[0] = *p++; + buf[1] = *p++; + buf[2] = *p++; + buf[3] = *p++; + tmpPtr[i] = strtol(buf, NULL, 16); + p += 2; + } + + while (tmpPtr < tmpEnd) { + UTF32 ch; + unsigned short bytesToWrite = 0; + const UTF32 byteMask = 0xBF; + const UTF32 byteMark = 0x80; + ch = *tmpPtr++; + /* If we have a surrogate pair, convert to UTF32 first. */ + if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { + /* If the 16 bits following the high surrogate are in the source + * buffer... */ + if (tmpPtr < tmpEnd) { + UTF32 ch2 = *tmpPtr; + /* If it's a low surrogate, convert to UTF32. */ + if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) { + ch = ((ch - UNI_SUR_HIGH_START) << halfShift) + + (ch2 - UNI_SUR_LOW_START) + halfBase; + ++tmpPtr; + } else if (flags == strictConversion) { /* it's an unpaired high surrogate */ + free(tmp); + rb_raise(rb_path2class("JSON::ParserError"), + "source sequence is illegal/malformed near %s", source); + } + } else { /* We don't have the 16 bits following the high surrogate. */ + free(tmp); + rb_raise(rb_path2class("JSON::ParserError"), + "partial character in source, but hit end near %s", source); + break; + } + } else if (flags == strictConversion) { + /* UTF-16 surrogate values are illegal in UTF-32 */ + if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) { + free(tmp); + rb_raise(rb_path2class("JSON::ParserError"), + "source sequence is illegal/malformed near %s", source); + } + } + /* Figure out how many bytes the result will require */ + if (ch < (UTF32) 0x80) { + bytesToWrite = 1; + } else if (ch < (UTF32) 0x800) { + bytesToWrite = 2; + } else if (ch < (UTF32) 0x10000) { + bytesToWrite = 3; + } else if (ch < (UTF32) 0x110000) { + bytesToWrite = 4; + } else { + bytesToWrite = 3; + ch = UNI_REPLACEMENT_CHAR; + } + + buf[0] = 0; + buf[1] = 0; + buf[2] = 0; + buf[3] = 0; + p = buf + bytesToWrite; + switch (bytesToWrite) { /* note: everything falls through. */ + case 4: *--p = (UTF8) ((ch | byteMark) & byteMask); ch >>= 6; + case 3: *--p = (UTF8) ((ch | byteMark) & byteMask); ch >>= 6; + case 2: *--p = (UTF8) ((ch | byteMark) & byteMask); ch >>= 6; + case 1: *--p = (UTF8) (ch | firstByteMark[bytesToWrite]); + } + rb_str_buf_cat(buffer, p, bytesToWrite); + } + free(tmp); + source += 5 + (n - 1) * 6; + return source; +} |