[llvm] r173923 - Move UTF conversion routines from clang/lib/Basic to llvm/lib/Support

Dmitri Gribenko gribozavr at gmail.com
Wed Jan 30 04:05:05 PST 2013


Author: gribozavr
Date: Wed Jan 30 06:05:05 2013
New Revision: 173923

URL: http://llvm.org/viewvc/llvm-project?rev=173923&view=rev
Log:
Move UTF conversion routines from clang/lib/Basic to llvm/lib/Support

This is required to use them in TableGen.

Added:
    llvm/trunk/include/llvm/Support/ConvertUTF.h
    llvm/trunk/lib/Support/ConvertUTF.c
    llvm/trunk/lib/Support/ConvertUTFWrapper.cpp
Modified:
    llvm/trunk/lib/Support/CMakeLists.txt

Added: llvm/trunk/include/llvm/Support/ConvertUTF.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/ConvertUTF.h?rev=173923&view=auto
==============================================================================
--- llvm/trunk/include/llvm/Support/ConvertUTF.h (added)
+++ llvm/trunk/include/llvm/Support/ConvertUTF.h Wed Jan 30 06:05:05 2013
@@ -0,0 +1,230 @@
+/*===--- ConvertUTF.h - Universal Character Names conversions ---------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ *==------------------------------------------------------------------------==*/
+/*
+ * 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.
+ */
+
+/* ---------------------------------------------------------------------
+
+    Conversions between UTF32, UTF-16, and UTF-8.  Header file.
+
+    Several funtions are included here, forming a complete set of
+    conversions between the three formats.  UTF-7 is not included
+    here, but is handled in a separate source file.
+
+    Each of these routines takes pointers to input buffers and output
+    buffers.  The input buffers are const.
+
+    Each routine converts the text between *sourceStart and sourceEnd,
+    putting the result into the buffer between *targetStart and
+    targetEnd. Note: the end pointers are *after* the last item: e.g.
+    *(sourceEnd - 1) is the last item.
+
+    The return result indicates whether the conversion was successful,
+    and if not, whether the problem was in the source or target buffers.
+    (Only the first encountered problem is indicated.)
+
+    After the conversion, *sourceStart and *targetStart are both
+    updated to point to the end of last text successfully converted in
+    the respective buffers.
+
+    Input parameters:
+        sourceStart - pointer to a pointer to the source buffer.
+                The contents of this are modified on return so that
+                it points at the next thing to be converted.
+        targetStart - similarly, pointer to pointer to the target buffer.
+        sourceEnd, targetEnd - respectively pointers to the ends of the
+                two buffers, for overflow checking only.
+
+    These conversion functions take a ConversionFlags argument. When this
+    flag is set to strict, both irregular sequences and isolated surrogates
+    will cause an error.  When the flag is set to lenient, both irregular
+    sequences and isolated surrogates are converted.
+
+    Whether the flag is strict or lenient, all illegal sequences will cause
+    an error return. This includes sequences such as: <F4 90 80 80>, <C0 80>,
+    or <A0> in UTF-8, and values above 0x10FFFF in UTF-32. Conformant code
+    must check for illegal sequences.
+
+    When the flag is set to lenient, characters over 0x10FFFF are converted
+    to the replacement character; otherwise (when the flag is set to strict)
+    they constitute an error.
+
+    Output parameters:
+        The value "sourceIllegal" is returned from some routines if the input
+        sequence is malformed.  When "sourceIllegal" is returned, the source
+        value will point to the illegal value that caused the problem. E.g.,
+        in UTF-8 when a sequence is malformed, it points to the start of the
+        malformed sequence.
+
+    Author: Mark E. Davis, 1994.
+    Rev History: Rick McGowan, fixes & updates May 2001.
+         Fixes & updates, Sept 2001.
+
+------------------------------------------------------------------------ */
+
+#ifndef CLANG_BASIC_CONVERTUTF_H
+#define CLANG_BASIC_CONVERTUTF_H
+
+/* ---------------------------------------------------------------------
+    The following 4 definitions are compiler-specific.
+    The C standard does not guarantee that wchar_t has at least
+    16 bits, so wchar_t is no less portable than unsigned short!
+    All should be unsigned values to avoid sign extension during
+    bit mask & shift operations.
+------------------------------------------------------------------------ */
+
+typedef unsigned int    UTF32;  /* at least 32 bits */
+typedef unsigned short  UTF16;  /* at least 16 bits */
+typedef unsigned char   UTF8;   /* typically 8 bits */
+typedef unsigned char   Boolean; /* 0 or 1 */
+
+/* Some fundamental constants */
+#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_MAX_UTF8_BYTES_PER_CODE_POINT 4
+
+typedef enum {
+  conversionOK,           /* conversion successful */
+  sourceExhausted,        /* partial character in source, but hit end */
+  targetExhausted,        /* insuff. room in target for conversion */
+  sourceIllegal           /* source sequence is illegal/malformed */
+} ConversionResult;
+
+typedef enum {
+  strictConversion = 0,
+  lenientConversion
+} ConversionFlags;
+
+/* This is for C++ and does no harm in C */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+ConversionResult ConvertUTF8toUTF16 (
+  const UTF8** sourceStart, const UTF8* sourceEnd,
+  UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
+
+ConversionResult ConvertUTF8toUTF32 (
+  const UTF8** sourceStart, const UTF8* sourceEnd,
+  UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
+
+#ifdef CLANG_NEEDS_THESE_ONE_DAY
+ConversionResult ConvertUTF16toUTF8 (
+  const UTF16** sourceStart, const UTF16* sourceEnd,
+  UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
+#endif
+
+ConversionResult ConvertUTF32toUTF8 (
+  const UTF32** sourceStart, const UTF32* sourceEnd,
+  UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags);
+
+ConversionResult ConvertUTF16toUTF32 (
+  const UTF16** sourceStart, const UTF16* sourceEnd,
+  UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags);
+
+ConversionResult ConvertUTF32toUTF16 (
+  const UTF32** sourceStart, const UTF32* sourceEnd,
+  UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags);
+
+Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd);
+
+Boolean isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd);
+
+unsigned getNumBytesForUTF8(UTF8 firstByte);
+
+#ifdef __cplusplus
+}
+
+/*************************************************************************/
+/* Below are LLVM-specific wrappers of the functions above. */
+
+#include "llvm/ADT/StringRef.h"
+
+namespace llvm {
+
+/**
+ * Convert an UTF8 StringRef to UTF8, UTF16, or UTF32 depending on
+ * WideCharWidth. The converted data is written to ResultPtr, which needs to
+ * point to at least WideCharWidth * (Source.Size() + 1) bytes. On success,
+ * ResultPtr will point one after the end of the copied string. On failure,
+ * ResultPtr will not be changed, and ErrorPtr will be set to the location of
+ * the first character which could not be converted.
+ * \return true on success.
+ */
+bool ConvertUTF8toWide(unsigned WideCharWidth, llvm::StringRef Source,
+                       char *&ResultPtr, const UTF8 *&ErrorPtr);
+
+/**
+ * Convert an Unicode code point to UTF8 sequence.
+ *
+ * \param Source a Unicode code point.
+ * \param [in,out] ResultPtr pointer to the output buffer, needs to be at least
+ * \c UNI_MAX_UTF8_BYTES_PER_CODE_POINT bytes.  On success \c ResultPtr is
+ * updated one past end of the converted sequence.
+ *
+ * \returns true on success.
+ */
+bool ConvertCodePointToUTF8(unsigned Source, char *&ResultPtr);
+
+/**
+ * Convert the first UTF8 sequence in the given source buffer to a UTF32
+ * code point.
+ *
+ * \param [in,out] source A pointer to the source buffer. If the conversion
+ * succeeds, this pointer will be updated to point to the byte just past the
+ * end of the converted sequence.
+ * \param sourceEnd A pointer just past the end of the source buffer.
+ * \param [out] target The converted code
+ * \param flags Whether the conversion is strict or lenient.
+ *
+ * \returns conversionOK on success
+ *
+ * \sa ConvertUTF8toUTF32
+ */
+static inline ConversionResult convertUTF8Sequence(const UTF8 **source,
+                                                   const UTF8 *sourceEnd,
+                                                   UTF32 *target,
+                                                   ConversionFlags flags) {
+  if (*source == sourceEnd)
+    return sourceExhausted;
+  unsigned size = getNumBytesForUTF8(**source);
+  if ((ptrdiff_t)size > sourceEnd - *source)
+    return sourceExhausted;
+  return ConvertUTF8toUTF32(source, *source + size, &target, target + 1, flags);
+}
+} // end namespace llvm
+
+#endif
+
+/* --------------------------------------------------------------------- */
+
+#endif

Modified: llvm/trunk/lib/Support/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/CMakeLists.txt?rev=173923&r1=173922&r2=173923&view=diff
==============================================================================
--- llvm/trunk/lib/Support/CMakeLists.txt (original)
+++ llvm/trunk/lib/Support/CMakeLists.txt Wed Jan 30 06:05:05 2013
@@ -8,6 +8,8 @@ add_llvm_library(LLVMSupport
   circular_raw_ostream.cpp
   CommandLine.cpp
   ConstantRange.cpp
+  ConvertUTF.c
+  ConvertUTFWrapper.cpp
   CrashRecoveryContext.cpp
   DataExtractor.cpp
   DataStream.cpp

Added: llvm/trunk/lib/Support/ConvertUTF.c
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/ConvertUTF.c?rev=173923&view=auto
==============================================================================
--- llvm/trunk/lib/Support/ConvertUTF.c (added)
+++ llvm/trunk/lib/Support/ConvertUTF.c Wed Jan 30 06:05:05 2013
@@ -0,0 +1,571 @@
+/*===--- ConvertUTF.c - Universal Character Names conversions ---------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------=*/
+/*
+ * 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.
+ */
+
+/* ---------------------------------------------------------------------
+
+    Conversions between UTF32, UTF-16, and UTF-8. Source code file.
+    Author: Mark E. Davis, 1994.
+    Rev History: Rick McGowan, fixes & updates May 2001.
+    Sept 2001: fixed const & error conditions per
+        mods suggested by S. Parent & A. Lillich.
+    June 2002: Tim Dodd added detection and handling of incomplete
+        source sequences, enhanced error detection, added casts
+        to eliminate compiler warnings.
+    July 2003: slight mods to back out aggressive FFFE detection.
+    Jan 2004: updated switches in from-UTF8 conversions.
+    Oct 2004: updated to use UNI_MAX_LEGAL_UTF32 in UTF-32 conversions.
+
+    See the header file "ConvertUTF.h" for complete documentation.
+
+------------------------------------------------------------------------ */
+
+
+#include "llvm/Support/ConvertUTF.h"
+#ifdef CVTUTF_DEBUG
+#include <stdio.h>
+#endif
+
+static const int halfShift  = 10; /* used for shifting by 10 bits */
+
+static const UTF32 halfBase = 0x0010000UL;
+static const UTF32 halfMask = 0x3FFUL;
+
+#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
+#define false      0
+#define true        1
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * 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 };
+
+/* --------------------------------------------------------------------- */
+
+/* The interface converts a whole buffer to avoid function-call overhead.
+ * Constants have been gathered. Loops & conditionals have been removed as
+ * much as possible for efficiency, in favor of drop-through switches.
+ * (See "Note A" at the bottom of the file for equivalent code.)
+ * If your compiler supports it, the "isLegalUTF8" call can be turned
+ * into an inline function.
+ */
+
+
+/* --------------------------------------------------------------------- */
+
+ConversionResult ConvertUTF32toUTF16 (
+        const UTF32** sourceStart, const UTF32* sourceEnd, 
+        UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF32* source = *sourceStart;
+    UTF16* target = *targetStart;
+    while (source < sourceEnd) {
+        UTF32 ch;
+        if (target >= targetEnd) {
+            result = targetExhausted; break;
+        }
+        ch = *source++;
+        if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
+            /* UTF-16 surrogate values are illegal in UTF-32; 0xffff or 0xfffe are both reserved values */
+            if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
+                if (flags == strictConversion) {
+                    --source; /* return to the illegal value itself */
+                    result = sourceIllegal;
+                    break;
+                } else {
+                    *target++ = UNI_REPLACEMENT_CHAR;
+                }
+            } else {
+                *target++ = (UTF16)ch; /* normal case */
+            }
+        } else if (ch > UNI_MAX_LEGAL_UTF32) {
+            if (flags == strictConversion) {
+                result = sourceIllegal;
+            } else {
+                *target++ = UNI_REPLACEMENT_CHAR;
+            }
+        } else {
+            /* target is a character in range 0xFFFF - 0x10FFFF. */
+            if (target + 1 >= targetEnd) {
+                --source; /* Back up source pointer! */
+                result = targetExhausted; break;
+            }
+            ch -= halfBase;
+            *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
+            *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
+        }
+    }
+    *sourceStart = source;
+    *targetStart = target;
+    return result;
+}
+
+/* --------------------------------------------------------------------- */
+
+ConversionResult ConvertUTF16toUTF32 (
+        const UTF16** sourceStart, const UTF16* sourceEnd, 
+        UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF16* source = *sourceStart;
+    UTF32* target = *targetStart;
+    UTF32 ch, ch2;
+    while (source < sourceEnd) {
+        const UTF16* oldSource = source; /*  In case we have to back up because of target overflow. */
+        ch = *source++;
+        /* 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 (source < sourceEnd) {
+                ch2 = *source;
+                /* 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;
+                    ++source;
+                } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
+                    --source; /* return to the illegal value itself */
+                    result = sourceIllegal;
+                    break;
+                }
+            } else { /* We don't have the 16 bits following the high surrogate. */
+                --source; /* return to the high surrogate */
+                result = sourceExhausted;
+                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) {
+                --source; /* return to the illegal value itself */
+                result = sourceIllegal;
+                break;
+            }
+        }
+        if (target >= targetEnd) {
+            source = oldSource; /* Back up source pointer! */
+            result = targetExhausted; break;
+        }
+        *target++ = ch;
+    }
+    *sourceStart = source;
+    *targetStart = target;
+#ifdef CVTUTF_DEBUG
+if (result == sourceIllegal) {
+    fprintf(stderr, "ConvertUTF16toUTF32 illegal seq 0x%04x,%04x\n", ch, ch2);
+    fflush(stderr);
+}
+#endif
+    return result;
+}
+ConversionResult ConvertUTF16toUTF8 (
+        const UTF16** sourceStart, const UTF16* sourceEnd, 
+        UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF16* source = *sourceStart;
+    UTF8* target = *targetStart;
+    while (source < sourceEnd) {
+        UTF32 ch;
+        unsigned short bytesToWrite = 0;
+        const UTF32 byteMask = 0xBF;
+        const UTF32 byteMark = 0x80; 
+        const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */
+        ch = *source++;
+        /* 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 (source < sourceEnd) {
+                UTF32 ch2 = *source;
+                /* 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;
+                    ++source;
+                } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
+                    --source; /* return to the illegal value itself */
+                    result = sourceIllegal;
+                    break;
+                }
+            } else { /* We don't have the 16 bits following the high surrogate. */
+                --source; /* return to the high surrogate */
+                result = sourceExhausted;
+                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) {
+                --source; /* return to the illegal value itself */
+                result = sourceIllegal;
+                break;
+            }
+        }
+        /* 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;
+        }
+
+        target += bytesToWrite;
+        if (target > targetEnd) {
+            source = oldSource; /* Back up source pointer! */
+            target -= bytesToWrite; result = targetExhausted; break;
+        }
+        switch (bytesToWrite) { /* note: everything falls through. */
+            case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 1: *--target =  (UTF8)(ch | firstByteMark[bytesToWrite]);
+        }
+        target += bytesToWrite;
+    }
+    *sourceStart = source;
+    *targetStart = target;
+    return result;
+}
+
+/* --------------------------------------------------------------------- */
+
+ConversionResult ConvertUTF32toUTF8 (
+        const UTF32** sourceStart, const UTF32* sourceEnd, 
+        UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF32* source = *sourceStart;
+    UTF8* target = *targetStart;
+    while (source < sourceEnd) {
+        UTF32 ch;
+        unsigned short bytesToWrite = 0;
+        const UTF32 byteMask = 0xBF;
+        const UTF32 byteMark = 0x80; 
+        ch = *source++;
+        if (flags == strictConversion ) {
+            /* UTF-16 surrogate values are illegal in UTF-32 */
+            if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
+                --source; /* return to the illegal value itself */
+                result = sourceIllegal;
+                break;
+            }
+        }
+        /*
+         * Figure out how many bytes the result will require. Turn any
+         * illegally large UTF32 things (> Plane 17) into replacement chars.
+         */
+        if (ch < (UTF32)0x80) {      bytesToWrite = 1;
+        } else if (ch < (UTF32)0x800) {     bytesToWrite = 2;
+        } else if (ch < (UTF32)0x10000) {   bytesToWrite = 3;
+        } else if (ch <= UNI_MAX_LEGAL_UTF32) {  bytesToWrite = 4;
+        } else {                            bytesToWrite = 3;
+                                            ch = UNI_REPLACEMENT_CHAR;
+                                            result = sourceIllegal;
+        }
+        
+        target += bytesToWrite;
+        if (target > targetEnd) {
+            --source; /* Back up source pointer! */
+            target -= bytesToWrite; result = targetExhausted; break;
+        }
+        switch (bytesToWrite) { /* note: everything falls through. */
+            case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
+            case 1: *--target = (UTF8) (ch | firstByteMark[bytesToWrite]);
+        }
+        target += bytesToWrite;
+    }
+    *sourceStart = source;
+    *targetStart = target;
+    return result;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Utility routine to tell whether a sequence of bytes is legal UTF-8.
+ * This must be called with the length pre-determined by the first byte.
+ * If not calling this from ConvertUTF8to*, then the length can be set by:
+ *  length = trailingBytesForUTF8[*source]+1;
+ * and the sequence is illegal right away if there aren't that many bytes
+ * available.
+ * If presented with a length > 4, this returns false.  The Unicode
+ * definition of UTF-8 goes up to 4-byte sequences.
+ */
+
+static Boolean isLegalUTF8(const UTF8 *source, int length) {
+    UTF8 a;
+    const UTF8 *srcptr = source+length;
+    switch (length) {
+    default: return false;
+        /* Everything else falls through when "true"... */
+    case 4: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
+    case 3: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
+    case 2: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
+
+        switch (*source) {
+            /* no fall-through in this inner switch */
+            case 0xE0: if (a < 0xA0) return false; break;
+            case 0xED: if (a > 0x9F) return false; break;
+            case 0xF0: if (a < 0x90) return false; break;
+            case 0xF4: if (a > 0x8F) return false; break;
+            default:   if (a < 0x80) return false;
+        }
+
+    case 1: if (*source >= 0x80 && *source < 0xC2) return false;
+    }
+    if (*source > 0xF4) return false;
+    return true;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Exported function to return whether a UTF-8 sequence is legal or not.
+ * This is not used here; it's just exported.
+ */
+Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd) {
+    int length = trailingBytesForUTF8[*source]+1;
+    if (length > sourceEnd - source) {
+        return false;
+    }
+    return isLegalUTF8(source, length);
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Exported function to return the total number of bytes in a codepoint
+ * represented in UTF-8, given the value of the first byte.
+ */
+unsigned getNumBytesForUTF8(UTF8 first) {
+  return trailingBytesForUTF8[first] + 1;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Exported function to return whether a UTF-8 string is legal or not.
+ * This is not used here; it's just exported.
+ */
+Boolean isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd) {
+    while (*source != sourceEnd) {
+        int length = trailingBytesForUTF8[**source] + 1;
+        if (length > sourceEnd - *source || !isLegalUTF8(*source, length))
+            return false;
+        *source += length;
+    }
+    return true;
+}
+
+/* --------------------------------------------------------------------- */
+
+ConversionResult ConvertUTF8toUTF16 (
+        const UTF8** sourceStart, const UTF8* sourceEnd, 
+        UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF8* source = *sourceStart;
+    UTF16* target = *targetStart;
+    while (source < sourceEnd) {
+        UTF32 ch = 0;
+        unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
+        if (extraBytesToRead >= sourceEnd - source) {
+            result = sourceExhausted; break;
+        }
+        /* Do this check whether lenient or strict */
+        if (!isLegalUTF8(source, extraBytesToRead+1)) {
+            result = sourceIllegal;
+            break;
+        }
+        /*
+         * 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 (target >= targetEnd) {
+            source -= (extraBytesToRead+1); /* Back up source pointer! */
+            result = targetExhausted; break;
+        }
+        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 (flags == strictConversion) {
+                    source -= (extraBytesToRead+1); /* return to the illegal value itself */
+                    result = sourceIllegal;
+                    break;
+                } else {
+                    *target++ = UNI_REPLACEMENT_CHAR;
+                }
+            } else {
+                *target++ = (UTF16)ch; /* normal case */
+            }
+        } else if (ch > UNI_MAX_UTF16) {
+            if (flags == strictConversion) {
+                result = sourceIllegal;
+                source -= (extraBytesToRead+1); /* return to the start */
+                break; /* Bail out; shouldn't continue */
+            } else {
+                *target++ = UNI_REPLACEMENT_CHAR;
+            }
+        } else {
+            /* target is a character in range 0xFFFF - 0x10FFFF. */
+            if (target + 1 >= targetEnd) {
+                source -= (extraBytesToRead+1); /* Back up source pointer! */
+                result = targetExhausted; break;
+            }
+            ch -= halfBase;
+            *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
+            *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
+        }
+    }
+    *sourceStart = source;
+    *targetStart = target;
+    return result;
+}
+
+/* --------------------------------------------------------------------- */
+
+ConversionResult ConvertUTF8toUTF32 (
+        const UTF8** sourceStart, const UTF8* sourceEnd, 
+        UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) {
+    ConversionResult result = conversionOK;
+    const UTF8* source = *sourceStart;
+    UTF32* target = *targetStart;
+    while (source < sourceEnd) {
+        UTF32 ch = 0;
+        unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
+        if (extraBytesToRead >= sourceEnd - source) {
+            result = sourceExhausted; break;
+        }
+        /* Do this check whether lenient or strict */
+        if (!isLegalUTF8(source, extraBytesToRead+1)) {
+            result = sourceIllegal;
+            break;
+        }
+        /*
+         * The cases all fall through. See "Note A" below.
+         */
+        switch (extraBytesToRead) {
+            case 5: ch += *source++; ch <<= 6;
+            case 4: ch += *source++; ch <<= 6;
+            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 (target >= targetEnd) {
+            source -= (extraBytesToRead+1); /* Back up the source pointer! */
+            result = targetExhausted; break;
+        }
+        if (ch <= UNI_MAX_LEGAL_UTF32) {
+            /*
+             * UTF-16 surrogate values are illegal in UTF-32, and anything
+             * over Plane 17 (> 0x10FFFF) is illegal.
+             */
+            if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
+                if (flags == strictConversion) {
+                    source -= (extraBytesToRead+1); /* return to the illegal value itself */
+                    result = sourceIllegal;
+                    break;
+                } else {
+                    *target++ = UNI_REPLACEMENT_CHAR;
+                }
+            } else {
+                *target++ = ch;
+            }
+        } else { /* i.e., ch > UNI_MAX_LEGAL_UTF32 */
+            result = sourceIllegal;
+            *target++ = UNI_REPLACEMENT_CHAR;
+        }
+    }
+    *sourceStart = source;
+    *targetStart = target;
+    return result;
+}
+
+/* ---------------------------------------------------------------------
+
+    Note A.
+    The fall-through switches in UTF-8 reading code save a
+    temp variable, some decrements & conditionals.  The switches
+    are equivalent to the following loop:
+        {
+            int tmpBytesToRead = extraBytesToRead+1;
+            do {
+                ch += *source++;
+                --tmpBytesToRead;
+                if (tmpBytesToRead) ch <<= 6;
+            } while (tmpBytesToRead > 0);
+        }
+    In UTF-8 writing code, the switches on "bytesToWrite" are
+    similarly unrolled loops.
+
+   --------------------------------------------------------------------- */

Added: llvm/trunk/lib/Support/ConvertUTFWrapper.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/ConvertUTFWrapper.cpp?rev=173923&view=auto
==============================================================================
--- llvm/trunk/lib/Support/ConvertUTFWrapper.cpp (added)
+++ llvm/trunk/lib/Support/ConvertUTFWrapper.cpp Wed Jan 30 06:05:05 2013
@@ -0,0 +1,76 @@
+//===-- ConvertUTFWrapper.cpp - Wrap ConvertUTF.h with clang data types -----===
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/ConvertUTF.h"
+
+namespace llvm {
+
+bool ConvertUTF8toWide(unsigned WideCharWidth, llvm::StringRef Source,
+                       char *&ResultPtr, const UTF8 *&ErrorPtr) {
+  assert(WideCharWidth == 1 || WideCharWidth == 2 || WideCharWidth == 4);
+  ConversionResult result = conversionOK;
+  // Copy the character span over.
+  if (WideCharWidth == 1) {
+    const UTF8 *Pos = reinterpret_cast<const UTF8*>(Source.begin());
+    if (!isLegalUTF8String(&Pos, reinterpret_cast<const UTF8*>(Source.end()))) {
+      result = sourceIllegal;
+      ErrorPtr = Pos;
+    } else {
+      memcpy(ResultPtr, Source.data(), Source.size());
+      ResultPtr += Source.size();
+    }
+  } else if (WideCharWidth == 2) {
+    const UTF8 *sourceStart = (const UTF8*)Source.data();
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF16 *targetStart = reinterpret_cast<UTF16*>(ResultPtr);
+    ConversionFlags flags = strictConversion;
+    result = ConvertUTF8toUTF16(
+        &sourceStart, sourceStart + Source.size(),
+        &targetStart, targetStart + 2*Source.size(), flags);
+    if (result == conversionOK)
+      ResultPtr = reinterpret_cast<char*>(targetStart);
+    else
+      ErrorPtr = sourceStart;
+  } else if (WideCharWidth == 4) {
+    const UTF8 *sourceStart = (const UTF8*)Source.data();
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF32 *targetStart = reinterpret_cast<UTF32*>(ResultPtr);
+    ConversionFlags flags = strictConversion;
+    result = ConvertUTF8toUTF32(
+        &sourceStart, sourceStart + Source.size(),
+        &targetStart, targetStart + 4*Source.size(), flags);
+    if (result == conversionOK)
+      ResultPtr = reinterpret_cast<char*>(targetStart);
+    else
+      ErrorPtr = sourceStart;
+  }
+  assert((result != targetExhausted)
+         && "ConvertUTF8toUTFXX exhausted target buffer");
+  return result == conversionOK;
+}
+
+bool ConvertCodePointToUTF8(unsigned Source, char *&ResultPtr) {
+  const UTF32 *SourceStart = &Source;
+  const UTF32 *SourceEnd = SourceStart + 1;
+  UTF8 *TargetStart = reinterpret_cast<UTF8 *>(ResultPtr);
+  UTF8 *TargetEnd = TargetStart + 4;
+  ConversionResult CR = ConvertUTF32toUTF8(&SourceStart, SourceEnd,
+                                           &TargetStart, TargetEnd,
+                                           strictConversion);
+  if (CR != conversionOK)
+    return false;
+
+  ResultPtr = reinterpret_cast<char*>(TargetStart);
+  return true;
+}
+
+} // end namespace llvm
+





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