[ruby/json] Delete code that is based on CVTUTF

I did this based on manual inspection, comparing the code to my re-created
history of CVTUTF at https://git.lukeshu.com/2git/cvtutf/ (created by the
scripts at https://git.lukeshu.com/2git/cvtutf-make/)

https://github.com/ruby/json/commit/0819553144

3 files changed, 0 insertions, 268 deletions

diff --git a/ext/json/generator/generator.c b/ext/json/generator/generator.c
index b8734764c7..d3f6516511 100644
--- a/ext/json/generator/generator.c
+++ b/ext/json/generator/generator.c
@@ -18,54 +18,6 @@ static ID i_to_s, i_to_json, i_new, i_indent, i_space, i_space_before,
           i_aref, i_send, i_respond_to_p, i_match, i_keys, i_depth,
           i_buffer_initial_length, i_dup, i_script_safe, i_escape_slash, i_strict;
 
-/*
- * 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 };
-
 /* Escapes the UTF16 character and stores the result in the buffer buf. */
 static void unicode_escape(char *buf, UTF16 character)
 {
@@ -94,98 +46,6 @@ static void convert_UTF8_to_JSON_ASCII(FBuffer *buffer, VALUE string, char scrip
     const UTF8 *sourceEnd = source + RSTRING_LEN(string);
     char buf[6] = { '\\', 'u' };
 
-    int ascii_only = rb_enc_str_asciionly_p(string);
-
-    if (!ascii_only) {
-        if (RB_ENCODING_GET_INLINED(string) != rb_utf8_encindex() || RB_ENC_CODERANGE(string) != RUBY_ENC_CODERANGE_VALID) {
-            rb_raise(rb_path2class("JSON::GeneratorError"),
-                    "source sequence is illegal/malformed utf-8");
-        }
-    }
-
-    while (source < sourceEnd) {
-        UTF32 ch = 0;
-        unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
-        /*
-         * The cases all fall through. See "Note A" below.
-         */
-        switch (extraBytesToRead) {
-            case 5: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
-            case 4: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
-            case 3: ch += *source++; ch <<= 6;
-            case 2: ch += *source++; ch <<= 6;
-            case 1: ch += *source++; ch <<= 6;
-            case 0: ch += *source++;
-        }
-        ch -= offsetsFromUTF8[extraBytesToRead];
-
-        if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
-            /* UTF-16 surrogate values are illegal in UTF-32 */
-            if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
-#if UNI_STRICT_CONVERSION
-                source -= (extraBytesToRead+1); /* return to the illegal value itself */
-                rb_raise(rb_path2class("JSON::GeneratorError"),
-                        "source sequence is illegal/malformed utf-8");
-#else
-                unicode_escape_to_buffer(buffer, buf, UNI_REPLACEMENT_CHAR);
-#endif
-            } else {
-                /* normal case */
-                if (ch >= 0x20 && ch <= 0x7f) {
-                    switch (ch) {
-                        case '\\':
-                            fbuffer_append(buffer, "\\\\", 2);
-                            break;
-                        case '"':
-                            fbuffer_append(buffer, "\\\"", 2);
-                            break;
-                        case '/':
-                            if(script_safe) {
-                                fbuffer_append(buffer, "\\/", 2);
-                                break;
-                            }
-                        default:
-                            fbuffer_append_char(buffer, (char)ch);
-                            break;
-                    }
-                } else {
-                    switch (ch) {
-                        case '\n':
-                            fbuffer_append(buffer, "\\n", 2);
-                            break;
-                        case '\r':
-                            fbuffer_append(buffer, "\\r", 2);
-                            break;
-                        case '\t':
-                            fbuffer_append(buffer, "\\t", 2);
-                            break;
-                        case '\f':
-                            fbuffer_append(buffer, "\\f", 2);
-                            break;
-                        case '\b':
-                            fbuffer_append(buffer, "\\b", 2);
-                            break;
-                        default:
-                            unicode_escape_to_buffer(buffer, buf, (UTF16) ch);
-                            break;
-                    }
-                }
-            }
-        } else if (ch > UNI_MAX_UTF16) {
-#if UNI_STRICT_CONVERSION
-            source -= (extraBytesToRead+1); /* return to the start */
-            rb_raise(rb_path2class("JSON::GeneratorError"),
-                    "source sequence is illegal/malformed utf8");
-#else
-            unicode_escape_to_buffer(buffer, buf, UNI_REPLACEMENT_CHAR);
-#endif
-        } else {
-            /* target is a character in range 0xFFFF - 0x10FFFF. */
-            ch -= halfBase;
-            unicode_escape_to_buffer(buffer, buf, (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START));
-            unicode_escape_to_buffer(buffer, buf, (UTF16)((ch & halfMask) + UNI_SUR_LOW_START));
-        }
-    }
     RB_GC_GUARD(string);
 }
 
@@ -202,98 +62,6 @@ static void convert_UTF8_to_JSON(FBuffer *buffer, VALUE string, char script_safe
     unsigned char c;
     char buf[6] = { '\\', 'u' };
     int ascii_only = rb_enc_str_asciionly_p(string);
-
-    if (!ascii_only) {
-        if (RB_ENCODING_GET_INLINED(string) != rb_utf8_encindex() || RB_ENC_CODERANGE(string) != RUBY_ENC_CODERANGE_VALID) {
-            rb_raise(rb_path2class("JSON::GeneratorError"),
-                    "source sequence is illegal/malformed utf-8");
-        }
-    }
-
-    for (start = 0, end = 0; end < len;) {
-        p = ptr + end;
-        c = (unsigned char) *p;
-        if (c < 0x20) {
-            switch (c) {
-                case '\n':
-                    escape = "\\n";
-                    escape_len = 2;
-                    break;
-                case '\r':
-                    escape = "\\r";
-                    escape_len = 2;
-                    break;
-                case '\t':
-                    escape = "\\t";
-                    escape_len = 2;
-                    break;
-                case '\f':
-                    escape = "\\f";
-                    escape_len = 2;
-                    break;
-                case '\b':
-                    escape = "\\b";
-                    escape_len = 2;
-                    break;
-                default:
-                    unicode_escape(buf, (UTF16) *p);
-                    escape = buf;
-                    escape_len = 6;
-                    break;
-            }
-        } else {
-            switch (c) {
-                case '\\':
-                    escape = "\\\\";
-                    escape_len = 2;
-                    break;
-                case '"':
-                    escape =  "\\\"";
-                    escape_len = 2;
-                    break;
-                case '/':
-                    if(script_safe) {
-                        escape = "\\/";
-                        escape_len = 2;
-                        break;
-                    }
-                default:
-                    {
-                        unsigned short clen = 1;
-                        if (!ascii_only) {
-                            clen += trailingBytesForUTF8[c];
-                            if (end + clen > len) {
-                                rb_raise(rb_path2class("JSON::GeneratorError"),
-                                        "partial character in source, but hit end");
-                            }
-
-                            if (script_safe && c == 0xE2) {
-                                unsigned char c2 = (unsigned char) *(p+1);
-                                unsigned char c3 = (unsigned char) *(p+2);
-                                if (c2 == 0x80 && (c3 == 0xA8 || c3 == 0xA9)) {
-                                    fbuffer_append(buffer, ptr + start, end - start);
-                                    start = end = (end + clen);
-                                    if (c3 == 0xA8) {
-                                        fbuffer_append(buffer, "\\u2028", 6);
-                                    } else {
-                                        fbuffer_append(buffer, "\\u2029", 6);
-                                    }
-                                    continue;
-                                }
-                            }
-                        }
-                        end += clen;
-                    }
-                    continue;
-                    break;
-            }
-        }
-        fbuffer_append(buffer, ptr + start, end - start);
-        fbuffer_append(buffer, escape, escape_len);
-        start = ++end;
-        escape = NULL;
-    }
-    fbuffer_append(buffer, ptr + start, end - start);
 }
 
 static char *fstrndup(const char *ptr, unsigned long len) {
diff --git a/ext/json/generator/generator.h b/ext/json/generator/generator.h
index 8dde7be827..95ce2479c6 100644
--- a/ext/json/generator/generator.h
+++ b/ext/json/generator/generator.h
@@ -22,30 +22,6 @@
 
 #define option_given_p(opts, key) RTEST(rb_funcall(opts, i_key_p, 1, key))
 
-/* unicode definitions */
-
-#define UNI_STRICT_CONVERSION 1
-
-typedef unsigned long  UTF32; /* at least 32 bits */
-typedef unsigned short UTF16; /* at least 16 bits */
-typedef unsigned char  UTF8;  /* typically 8 bits */
-
-#define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD
-#define UNI_MAX_BMP (UTF32)0x0000FFFF
-#define UNI_MAX_UTF16 (UTF32)0x0010FFFF
-#define UNI_MAX_UTF32 (UTF32)0x7FFFFFFF
-#define UNI_MAX_LEGAL_UTF32 (UTF32)0x0010FFFF
-
-#define UNI_SUR_HIGH_START  (UTF32)0xD800
-#define UNI_SUR_HIGH_END    (UTF32)0xDBFF
-#define UNI_SUR_LOW_START   (UTF32)0xDC00
-#define UNI_SUR_LOW_END     (UTF32)0xDFFF
-
-static const int halfShift  = 10; /* used for shifting by 10 bits */
-
-static const UTF32 halfBase = 0x0010000UL;
-static const UTF32 halfMask = 0x3FFUL;
-
 static void unicode_escape(char *buf, UTF16 character);
 static void unicode_escape_to_buffer(FBuffer *buffer, char buf[6], UTF16 character);
 static void convert_UTF8_to_JSON_ASCII(FBuffer *buffer, VALUE string, char script_safe);
diff --git a/ext/json/parser/parser.h b/ext/json/parser/parser.h
index 651d40c074..d80f1b7303 100644
--- a/ext/json/parser/parser.h
+++ b/ext/json/parser/parser.h
@@ -19,18 +19,6 @@
 
 #define option_given_p(opts, key) RTEST(rb_funcall(opts, i_key_p, 1, key))
 
-/* unicode */
-
-typedef unsigned long UTF32;  /* at least 32 bits */
-typedef unsigned short UTF16; /* at least 16 bits */
-typedef unsigned char UTF8;   /* typically 8 bits */
-
-#define UNI_REPLACEMENT_CHAR (UTF32)0x0000FFFD
-#define UNI_SUR_HIGH_START  (UTF32)0xD800
-#define UNI_SUR_HIGH_END    (UTF32)0xDBFF
-#define UNI_SUR_LOW_START   (UTF32)0xDC00
-#define UNI_SUR_LOW_END     (UTF32)0xDFFF
-
 typedef struct JSON_ParserStruct {
     VALUE Vsource;
     char *source;