Convert base dependencies to use sys_string_conversions instead of the ICU...

base/third_party/icu/icu_utf.cc

+/*
+******************************************************************************
+*
+*   Copyright (C) 1999-2006, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+******************************************************************************
+*   file name:  utf_impl.c
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 1999sep13
+*   created by: Markus W. Scherer
+*
+*   This file provides implementation functions for macros in the utfXX.h
+*   that would otherwise be too long as macros.
+*/
+
+#include "base/third_party/icu/icu_utf.h"
+
+namespace base_icu {
+
+/**
+ * UTF8_ERROR_VALUE_1 and UTF8_ERROR_VALUE_2 are special error values for UTF-8,
+ * which need 1 or 2 bytes in UTF-8:
+ * \code
+ * U+0015 = NAK = Negative Acknowledge, C0 control character
+ * U+009f = highest C1 control character
+ * \endcode
+ *
+ * These are used by UTF8_..._SAFE macros so that they can return an error value
+ * that needs the same number of code units (bytes) as were seen by
+ * a macro. They should be tested with UTF_IS_ERROR() or UTF_IS_VALID().
+ *
+ * @deprecated ICU 2.4. Obsolete, see utf_old.h.
+ */
+#define CBUTF8_ERROR_VALUE_1 0x15
+
+/**
+ * See documentation on UTF8_ERROR_VALUE_1 for details.
+ *
+ * @deprecated ICU 2.4. Obsolete, see utf_old.h.
+ */
+#define CBUTF8_ERROR_VALUE_2 0x9f
+
+
+/**
+ * Error value for all UTFs. This code point value will be set by macros with e>
+ * checking if an error is detected.
+ *
+ * @deprecated ICU 2.4. Obsolete, see utf_old.h.
+ */
+#define CBUTF_ERROR_VALUE 0xffff
+
+/*
+ * This table could be replaced on many machines by
+ * a few lines of assembler code using an
+ * "index of first 0-bit from msb" instruction and
+ * one or two more integer instructions.
+ *
+ * For example, on an i386, do something like
+ * - MOV AL, leadByte
+ * - NOT AL         (8-bit, leave b15..b8==0..0, reverse only b7..b0)
+ * - MOV AH, 0
+ * - BSR BX, AX     (16-bit)
+ * - MOV AX, 6      (result)
+ * - JZ finish      (ZF==1 if leadByte==0xff)
+ * - SUB AX, BX (result)
+ * -finish:
+ * (BSR: Bit Scan Reverse, scans for a 1-bit, starting from the MSB)
+ *
+ * In Unicode, all UTF-8 byte sequences with more than 4 bytes are illegal;
+ * lead bytes above 0xf4 are illegal.
+ * We keep them in this table for skipping long ISO 10646-UTF-8 sequences.
+ */
+const uint8
+utf8_countTrailBytes[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,    /* illegal in Unicode */
+    4, 4, 4, 4, /* illegal in Unicode */
+    5, 5,       /* illegal in Unicode */
+    0, 0        /* illegal bytes 0xfe and 0xff */
+};
+
+static const UChar32
+utf8_minLegal[4]={ 0, 0x80, 0x800, 0x10000 };
+
+static const UChar32
+utf8_errorValue[6]={
+    CBUTF8_ERROR_VALUE_1, CBUTF8_ERROR_VALUE_2, CBUTF_ERROR_VALUE, 0x10ffff,
+    0x3ffffff, 0x7fffffff
+};
+
+/*
+ * Handle the non-inline part of the U8_NEXT() macro and its obsolete sibling
+ * UTF8_NEXT_CHAR_SAFE().
+ *
+ * The "strict" parameter controls the error behavior:
+ * <0  "Safe" behavior of U8_NEXT(): All illegal byte sequences yield a negative
+ *     code point result.
+ *  0  Obsolete "safe" behavior of UTF8_NEXT_CHAR_SAFE(..., FALSE):
+ *     All illegal byte sequences yield a positive code point such that this
+ *     result code point would be encoded with the same number of bytes as
+ *     the illegal sequence.
+ * >0  Obsolete "strict" behavior of UTF8_NEXT_CHAR_SAFE(..., TRUE):
+ *     Same as the obsolete "safe" behavior, but non-characters are also treated
+ *     like illegal sequences.
+ *
+ * The special negative (<0) value -2 is used for lenient treatment of surrogate
+ * code points as legal. Some implementations use this for roundtripping of
+ * Unicode 16-bit strings that are not well-formed UTF-16, that is, they
+ * contain unpaired surrogates.
+ *
+ * Note that a UBool is the same as an int8_t.
+ */
+UChar32
+utf8_nextCharSafeBody(const uint8 *s, int32 *pi, int32 length, UChar32 c, UBool strict) {
+    int32 i=*pi;
+    uint8 count=CBU8_COUNT_TRAIL_BYTES(c);
+    if((i)+count<=(length)) {
+        uint8 trail, illegal=0;
+
+        CBU8_MASK_LEAD_BYTE((c), count);
+        /* count==0 for illegally leading trail bytes and the illegal bytes 0xfe and 0xff */
+        switch(count) {
+        /* each branch falls through to the next one */
+        case 5:
+        case 4:
+            /* count>=4 is always illegal: no more than 3 trail bytes in Unicode's UTF-8 */
+            illegal=1;
+            break;
+        case 3:
+            trail=s[(i)++];
+            (c)=((c)<<6)|(trail&0x3f);
+            if(c<0x110) {
+                illegal|=(trail&0xc0)^0x80;
+            } else {
+                /* code point>0x10ffff, outside Unicode */
+                illegal=1;
+                break;
+            }
+        case 2:
+            trail=s[(i)++];
+            (c)=((c)<<6)|(trail&0x3f);
+            illegal|=(trail&0xc0)^0x80;
+        case 1:
+            trail=s[(i)++];
+            (c)=((c)<<6)|(trail&0x3f);
+            illegal|=(trail&0xc0)^0x80;
+            break;
+        case 0:
+            if(strict>=0) {
+                return CBUTF8_ERROR_VALUE_1;
+            } else {
+                return CBU_SENTINEL;
+            }
+        /* no default branch to optimize switch()  - all values are covered */
+        }
+
+        /*
+         * All the error handling should return a value
+         * that needs count bytes so that UTF8_GET_CHAR_SAFE() works right.
+         *
+         * Starting with Unicode 3.0.1, non-shortest forms are illegal.
+         * Starting with Unicode 3.2, surrogate code points must not be
+         * encoded in UTF-8, and there are no irregular sequences any more.
+         *
+         * U8_ macros (new in ICU 2.4) return negative values for error conditions.
+         */
+
+        /* correct sequence - all trail bytes have (b7..b6)==(10)? */
+        /* illegal is also set if count>=4 */
+        if(illegal || (c)<utf8_minLegal[count] || (CBU_IS_SURROGATE(c) && strict!=-2)) {
+            /* error handling */
+            uint8 errorCount=count;
+            /* don't go beyond this sequence */
+            i=*pi;
+            while(count>0 && CBU8_IS_TRAIL(s[i])) {
+                ++(i);
+                --count;
+            }
+            if(strict>=0) {
+                c=utf8_errorValue[errorCount-count];
+            } else {
+                c=CBU_SENTINEL;
+            }
+        } else if((strict)>0 && CBU_IS_UNICODE_NONCHAR(c)) {
+            /* strict: forbid non-characters like U+fffe */
+            c=utf8_errorValue[count];
+        }
+    } else /* too few bytes left */ {
+        /* error handling */
+        int32 i0=i;
+        /* don't just set (i)=(length) in case there is an illegal sequence */
+        while((i)<(length) && CBU8_IS_TRAIL(s[i])) {
+            ++(i);
+        }
+        if(strict>=0) {
+            c=utf8_errorValue[i-i0];
+        } else {
+            c=CBU_SENTINEL;
+        }
+    }
+    *pi=i;
+    return c;
+}
+
+}  // namespace base_icu