The Tor Browser: toolkit/crashreporter/google-breakpad/src/common/convert

toolkit/crashreporter/google-breakpad/src/common/convert_UTF.c@6474c204b198 (annotated)

toolkit/crashreporter/google-breakpad/src/common/convert_UTF.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * 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 "convert_UTF.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
 /* --------------------------------------------------------------------- */
 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;
 }
 /* --------------------------------------------------------------------- */
 /*
  * 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,
 ,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, 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,
 x03C82080UL, 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 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;
 }
 /* --------------------------------------------------------------------- */
 /*
  * 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)) > 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 (source+length > sourceEnd) {
     return false;
   }
   return isLegalUTF8(source, length);
 }
 /* --------------------------------------------------------------------- */
 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 (source + extraBytesToRead >= sourceEnd) {
 	    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 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;
 }
 /* --------------------------------------------------------------------- */
 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 (source + extraBytesToRead >= sourceEnd) {
 	    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.
 --------------------------------------------------------------------- */

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toolkit/crashreporter/google-breakpad/src/common/convert_UTF.c@6474c204b198 (annotated)

toolkit/crashreporter/google-breakpad/src/common/convert_UTF.c