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      1 //---------------------------------------------------------------------------------
      2 //
      3 //  Little Color Management System
      4 //  Copyright (c) 1998-2010 Marti Maria Saguer
      5 //
      6 // Permission is hereby granted, free of charge, to any person obtaining
      7 // a copy of this software and associated documentation files (the "Software"),
      8 // to deal in the Software without restriction, including without limitation
      9 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
     10 // and/or sell copies of the Software, and to permit persons to whom the Software
     11 // is furnished to do so, subject to the following conditions:
     12 //
     13 // The above copyright notice and this permission notice shall be included in
     14 // all copies or substantial portions of the Software.
     15 //
     16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
     18 // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
     20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     23 //
     24 //---------------------------------------------------------------------------------
     25 //
     26 
     27 #include "lcms2_internal.h"
     28 
     29 
     30 // ----------------------------------------------------------------------------------
     31 // Encoding & Decoding support functions
     32 // ----------------------------------------------------------------------------------
     33 
     34 //      Little-Endian to Big-Endian
     35 
     36 // Adjust a word value after being readed/ before being written from/to an ICC profile
     37 cmsUInt16Number CMSEXPORT  _cmsAdjustEndianess16(cmsUInt16Number Word)
     38 {
     39 #ifndef CMS_USE_BIG_ENDIAN
     40 
     41     cmsUInt8Number* pByte = (cmsUInt8Number*) &Word;
     42     cmsUInt8Number tmp;
     43 
     44     tmp = pByte[0];
     45     pByte[0] = pByte[1];
     46     pByte[1] = tmp;
     47 #endif
     48 
     49     return Word;
     50 }
     51 
     52 
     53 // Transports to properly encoded values - note that icc profiles does use big endian notation.
     54 
     55 // 1 2 3 4
     56 // 4 3 2 1
     57 
     58 cmsUInt32Number CMSEXPORT  _cmsAdjustEndianess32(cmsUInt32Number DWord)
     59 {
     60 #ifndef CMS_USE_BIG_ENDIAN
     61 
     62     cmsUInt8Number* pByte = (cmsUInt8Number*) &DWord;
     63     cmsUInt8Number temp1;
     64     cmsUInt8Number temp2;
     65 
     66     temp1 = *pByte++;
     67     temp2 = *pByte++;
     68     *(pByte-1) = *pByte;
     69     *pByte++ = temp2;
     70     *(pByte-3) = *pByte;
     71     *pByte = temp1;
     72 #endif
     73     return DWord;
     74 }
     75 
     76 // 1 2 3 4 5 6 7 8
     77 // 8 7 6 5 4 3 2 1
     78 
     79 void CMSEXPORT  _cmsAdjustEndianess64(cmsUInt64Number* Result, cmsUInt64Number* QWord)
     80 {
     81 
     82 #ifndef CMS_USE_BIG_ENDIAN
     83 
     84     cmsUInt8Number* pIn  = (cmsUInt8Number*) QWord;
     85     cmsUInt8Number* pOut = (cmsUInt8Number*) Result;
     86 
     87     _cmsAssert(Result != NULL);
     88 
     89     pOut[7] = pIn[0];
     90     pOut[6] = pIn[1];
     91     pOut[5] = pIn[2];
     92     pOut[4] = pIn[3];
     93     pOut[3] = pIn[4];
     94     pOut[2] = pIn[5];
     95     pOut[1] = pIn[6];
     96     pOut[0] = pIn[7];
     97 
     98 #else
     99     _cmsAssert(Result != NULL);
    100 
    101 #  ifdef CMS_DONT_USE_INT64
    102     (*Result)[0] = QWord[0];
    103     (*Result)[1] = QWord[1];
    104 #  else
    105     *Result = *QWord;
    106 #  endif
    107 #endif
    108 }
    109 
    110 // Auxiliar -- read 8, 16 and 32-bit numbers
    111 cmsBool CMSEXPORT  _cmsReadUInt8Number(cmsIOHANDLER* io, cmsUInt8Number* n)
    112 {
    113     cmsUInt8Number tmp;
    114 
    115     _cmsAssert(io != NULL);
    116 
    117     if (io -> Read(io, &tmp, sizeof(cmsUInt8Number), 1) != 1)
    118             return FALSE;
    119 
    120     if (n != NULL) *n = tmp;
    121     return TRUE;
    122 }
    123 
    124 cmsBool CMSEXPORT  _cmsReadUInt16Number(cmsIOHANDLER* io, cmsUInt16Number* n)
    125 {
    126     cmsUInt16Number tmp;
    127 
    128     _cmsAssert(io != NULL);
    129 
    130     if (io -> Read(io, &tmp, sizeof(cmsUInt16Number), 1) != 1)
    131             return FALSE;
    132 
    133     if (n != NULL) *n = _cmsAdjustEndianess16(tmp);
    134     return TRUE;
    135 }
    136 
    137 cmsBool CMSEXPORT  _cmsReadUInt16Array(cmsIOHANDLER* io, cmsUInt32Number n, cmsUInt16Number* Array)
    138 {
    139     cmsUInt32Number i;
    140 
    141     _cmsAssert(io != NULL);
    142 
    143     for (i=0; i < n; i++) {
    144 
    145         if (Array != NULL) {
    146             if (!_cmsReadUInt16Number(io, Array + i)) return FALSE;
    147         }
    148         else {
    149             if (!_cmsReadUInt16Number(io, NULL)) return FALSE;
    150         }
    151 
    152     }
    153     return TRUE;
    154 }
    155 
    156 cmsBool CMSEXPORT  _cmsReadUInt32Number(cmsIOHANDLER* io, cmsUInt32Number* n)
    157 {
    158     cmsUInt32Number tmp;
    159 
    160     _cmsAssert(io != NULL);
    161 
    162     if (io -> Read(io, &tmp, sizeof(cmsUInt32Number), 1) != 1)
    163             return FALSE;
    164 
    165     if (n != NULL) *n = _cmsAdjustEndianess32(tmp);
    166     return TRUE;
    167 }
    168 
    169 cmsBool CMSEXPORT  _cmsReadFloat32Number(cmsIOHANDLER* io, cmsFloat32Number* n)
    170 {
    171     cmsUInt32Number tmp;
    172 
    173     _cmsAssert(io != NULL);
    174 
    175     if (io -> Read(io, &tmp, sizeof(cmsFloat32Number), 1) != 1)
    176             return FALSE;
    177 
    178     if (n != NULL) {
    179 
    180         tmp = _cmsAdjustEndianess32(tmp);
    181         *n = *(cmsFloat32Number*) &tmp;
    182     }
    183     return TRUE;
    184 }
    185 
    186 
    187 cmsBool CMSEXPORT   _cmsReadUInt64Number(cmsIOHANDLER* io, cmsUInt64Number* n)
    188 {
    189     cmsUInt64Number tmp;
    190 
    191     _cmsAssert(io != NULL);
    192 
    193     if (io -> Read(io, &tmp, sizeof(cmsUInt64Number), 1) != 1)
    194             return FALSE;
    195 
    196     if (n != NULL) _cmsAdjustEndianess64(n, &tmp);
    197     return TRUE;
    198 }
    199 
    200 
    201 cmsBool CMSEXPORT  _cmsRead15Fixed16Number(cmsIOHANDLER* io, cmsFloat64Number* n)
    202 {
    203     cmsUInt32Number tmp;
    204 
    205     _cmsAssert(io != NULL);
    206 
    207     if (io -> Read(io, &tmp, sizeof(cmsUInt32Number), 1) != 1)
    208             return FALSE;
    209 
    210     if (n != NULL) {
    211         *n = _cms15Fixed16toDouble(_cmsAdjustEndianess32(tmp));
    212     }
    213 
    214     return TRUE;
    215 }
    216 
    217 
    218 // Jun-21-2000: Some profiles (those that comes with W2K) comes
    219 // with the media white (media black?) x 100. Add a sanity check
    220 
    221 static
    222 void NormalizeXYZ(cmsCIEXYZ* Dest)
    223 {
    224     while (Dest -> X > 2. &&
    225            Dest -> Y > 2. &&
    226            Dest -> Z > 2.) {
    227 
    228                Dest -> X /= 10.;
    229                Dest -> Y /= 10.;
    230                Dest -> Z /= 10.;
    231        }
    232 }
    233 
    234 cmsBool CMSEXPORT  _cmsReadXYZNumber(cmsIOHANDLER* io, cmsCIEXYZ* XYZ)
    235 {
    236     cmsEncodedXYZNumber xyz;
    237 
    238     _cmsAssert(io != NULL);
    239 
    240     if (io ->Read(io, &xyz, sizeof(cmsEncodedXYZNumber), 1) != 1) return FALSE;
    241 
    242     if (XYZ != NULL) {
    243 
    244         XYZ->X = _cms15Fixed16toDouble(_cmsAdjustEndianess32(xyz.X));
    245         XYZ->Y = _cms15Fixed16toDouble(_cmsAdjustEndianess32(xyz.Y));
    246         XYZ->Z = _cms15Fixed16toDouble(_cmsAdjustEndianess32(xyz.Z));
    247 
    248         NormalizeXYZ(XYZ);
    249     }
    250     return TRUE;
    251 }
    252 
    253 cmsBool CMSEXPORT  _cmsWriteUInt8Number(cmsIOHANDLER* io, cmsUInt8Number n)
    254 {
    255     _cmsAssert(io != NULL);
    256 
    257     if (io -> Write(io, sizeof(cmsUInt8Number), &n) != 1)
    258             return FALSE;
    259 
    260     return TRUE;
    261 }
    262 
    263 cmsBool CMSEXPORT  _cmsWriteUInt16Number(cmsIOHANDLER* io, cmsUInt16Number n)
    264 {
    265     cmsUInt16Number tmp;
    266 
    267     _cmsAssert(io != NULL);
    268 
    269     tmp = _cmsAdjustEndianess16(n);
    270     if (io -> Write(io, sizeof(cmsUInt16Number), &tmp) != 1)
    271             return FALSE;
    272 
    273     return TRUE;
    274 }
    275 
    276 cmsBool CMSEXPORT  _cmsWriteUInt16Array(cmsIOHANDLER* io, cmsUInt32Number n, const cmsUInt16Number* Array)
    277 {
    278     cmsUInt32Number i;
    279 
    280     _cmsAssert(io != NULL);
    281     _cmsAssert(Array != NULL);
    282 
    283     for (i=0; i < n; i++) {
    284         if (!_cmsWriteUInt16Number(io, Array[i])) return FALSE;
    285     }
    286 
    287     return TRUE;
    288 }
    289 
    290 cmsBool CMSEXPORT  _cmsWriteUInt32Number(cmsIOHANDLER* io, cmsUInt32Number n)
    291 {
    292     cmsUInt32Number tmp;
    293 
    294     _cmsAssert(io != NULL);
    295 
    296     tmp = _cmsAdjustEndianess32(n);
    297     if (io -> Write(io, sizeof(cmsUInt32Number), &tmp) != 1)
    298             return FALSE;
    299 
    300     return TRUE;
    301 }
    302 
    303 
    304 cmsBool CMSEXPORT  _cmsWriteFloat32Number(cmsIOHANDLER* io, cmsFloat32Number n)
    305 {
    306     cmsUInt32Number tmp;
    307 
    308     _cmsAssert(io != NULL);
    309 
    310     tmp = *(cmsUInt32Number*) &n;
    311     tmp = _cmsAdjustEndianess32(tmp);
    312     if (io -> Write(io, sizeof(cmsUInt32Number), &tmp) != 1)
    313             return FALSE;
    314 
    315     return TRUE;
    316 }
    317 
    318 cmsBool CMSEXPORT  _cmsWriteUInt64Number(cmsIOHANDLER* io, cmsUInt64Number* n)
    319 {
    320     cmsUInt64Number tmp;
    321 
    322     _cmsAssert(io != NULL);
    323 
    324     _cmsAdjustEndianess64(&tmp, n);
    325     if (io -> Write(io, sizeof(cmsUInt64Number), &tmp) != 1)
    326             return FALSE;
    327 
    328     return TRUE;
    329 }
    330 
    331 cmsBool CMSEXPORT  _cmsWrite15Fixed16Number(cmsIOHANDLER* io, cmsFloat64Number n)
    332 {
    333     cmsUInt32Number tmp;
    334 
    335     _cmsAssert(io != NULL);
    336 
    337     tmp = _cmsAdjustEndianess32(_cmsDoubleTo15Fixed16(n));
    338     if (io -> Write(io, sizeof(cmsUInt32Number), &tmp) != 1)
    339             return FALSE;
    340 
    341     return TRUE;
    342 }
    343 
    344 cmsBool CMSEXPORT  _cmsWriteXYZNumber(cmsIOHANDLER* io, const cmsCIEXYZ* XYZ)
    345 {
    346     cmsEncodedXYZNumber xyz;
    347 
    348     _cmsAssert(io != NULL);
    349     _cmsAssert(XYZ != NULL);
    350 
    351     xyz.X = _cmsAdjustEndianess32(_cmsDoubleTo15Fixed16(XYZ->X));
    352     xyz.Y = _cmsAdjustEndianess32(_cmsDoubleTo15Fixed16(XYZ->Y));
    353     xyz.Z = _cmsAdjustEndianess32(_cmsDoubleTo15Fixed16(XYZ->Z));
    354 
    355     return io -> Write(io,  sizeof(cmsEncodedXYZNumber), &xyz);
    356 }
    357 
    358 // from Fixed point 8.8 to double
    359 cmsFloat64Number CMSEXPORT _cms8Fixed8toDouble(cmsUInt16Number fixed8)
    360 {
    361        cmsUInt8Number  msb, lsb;
    362 
    363        lsb = (cmsUInt8Number) (fixed8 & 0xff);
    364        msb = (cmsUInt8Number) (((cmsUInt16Number) fixed8 >> 8) & 0xff);
    365 
    366        return (cmsFloat64Number) ((cmsFloat64Number) msb + ((cmsFloat64Number) lsb / 256.0));
    367 }
    368 
    369 cmsUInt16Number CMSEXPORT _cmsDoubleTo8Fixed8(cmsFloat64Number val)
    370 {
    371     cmsS15Fixed16Number GammaFixed32 = _cmsDoubleTo15Fixed16(val);
    372     return  (cmsUInt16Number) ((GammaFixed32 >> 8) & 0xFFFF);
    373 }
    374 
    375 // from Fixed point 15.16 to double
    376 cmsFloat64Number CMSEXPORT _cms15Fixed16toDouble(cmsS15Fixed16Number fix32)
    377 {
    378     cmsFloat64Number floater, sign, mid;
    379     int Whole, FracPart;
    380 
    381     sign  = (fix32 < 0 ? -1 : 1);
    382     fix32 = abs(fix32);
    383 
    384     Whole     = (cmsUInt16Number)(fix32 >> 16) & 0xffff;
    385     FracPart  = (cmsUInt16Number)(fix32 & 0xffff);
    386 
    387     mid     = (cmsFloat64Number) FracPart / 65536.0;
    388     floater = (cmsFloat64Number) Whole + mid;
    389 
    390     return sign * floater;
    391 }
    392 
    393 // from double to Fixed point 15.16
    394 cmsS15Fixed16Number CMSEXPORT _cmsDoubleTo15Fixed16(cmsFloat64Number v)
    395 {
    396     return ((cmsS15Fixed16Number) floor((v)*65536.0 + 0.5));
    397 }
    398 
    399 // Date/Time functions
    400 
    401 void CMSEXPORT _cmsDecodeDateTimeNumber(const cmsDateTimeNumber *Source, struct tm *Dest)
    402 {
    403 
    404     _cmsAssert(Dest != NULL);
    405     _cmsAssert(Source != NULL);
    406 
    407     Dest->tm_sec   = _cmsAdjustEndianess16(Source->seconds);
    408     Dest->tm_min   = _cmsAdjustEndianess16(Source->minutes);
    409     Dest->tm_hour  = _cmsAdjustEndianess16(Source->hours);
    410     Dest->tm_mday  = _cmsAdjustEndianess16(Source->day);
    411     Dest->tm_mon   = _cmsAdjustEndianess16(Source->month) - 1;
    412     Dest->tm_year  = _cmsAdjustEndianess16(Source->year) - 1900;
    413     Dest->tm_wday  = -1;
    414     Dest->tm_yday  = -1;
    415     Dest->tm_isdst = 0;
    416 }
    417 
    418 void CMSEXPORT _cmsEncodeDateTimeNumber(cmsDateTimeNumber *Dest, const struct tm *Source)
    419 {
    420     _cmsAssert(Dest != NULL);
    421     _cmsAssert(Source != NULL);
    422 
    423     Dest->seconds = _cmsAdjustEndianess16((cmsUInt16Number) Source->tm_sec);
    424     Dest->minutes = _cmsAdjustEndianess16((cmsUInt16Number) Source->tm_min);
    425     Dest->hours   = _cmsAdjustEndianess16((cmsUInt16Number) Source->tm_hour);
    426     Dest->day     = _cmsAdjustEndianess16((cmsUInt16Number) Source->tm_mday);
    427     Dest->month   = _cmsAdjustEndianess16((cmsUInt16Number) (Source->tm_mon + 1));
    428     Dest->year    = _cmsAdjustEndianess16((cmsUInt16Number) (Source->tm_year + 1900));
    429 }
    430 
    431 // Read base and return type base
    432 cmsTagTypeSignature CMSEXPORT _cmsReadTypeBase(cmsIOHANDLER* io)
    433 {
    434     _cmsTagBase Base;
    435 
    436     _cmsAssert(io != NULL);
    437 
    438     if (io -> Read(io, &Base, sizeof(_cmsTagBase), 1) != 1)
    439         return (cmsTagTypeSignature) 0;
    440 
    441     return (cmsTagTypeSignature) _cmsAdjustEndianess32(Base.sig);
    442 }
    443 
    444 // Setup base marker
    445 cmsBool  CMSEXPORT _cmsWriteTypeBase(cmsIOHANDLER* io, cmsTagTypeSignature sig)
    446 {
    447     _cmsTagBase  Base;
    448 
    449     _cmsAssert(io != NULL);
    450 
    451     Base.sig = (cmsTagTypeSignature) _cmsAdjustEndianess32(sig);
    452     memset(&Base.reserved, 0, sizeof(Base.reserved));
    453     return io -> Write(io, sizeof(_cmsTagBase), &Base);
    454 }
    455 
    456 cmsBool CMSEXPORT _cmsReadAlignment(cmsIOHANDLER* io)
    457 {
    458     cmsUInt8Number  Buffer[4];
    459     cmsUInt32Number NextAligned, At;
    460     cmsUInt32Number BytesToNextAlignedPos;
    461 
    462     _cmsAssert(io != NULL);
    463 
    464     At = io -> Tell(io);
    465     NextAligned = _cmsALIGNLONG(At);
    466     BytesToNextAlignedPos = NextAligned - At;
    467     if (BytesToNextAlignedPos == 0) return TRUE;
    468     if (BytesToNextAlignedPos > 4)  return FALSE;
    469 
    470     return (io ->Read(io, Buffer, BytesToNextAlignedPos, 1) == 1);
    471 }
    472 
    473 cmsBool CMSEXPORT _cmsWriteAlignment(cmsIOHANDLER* io)
    474 {
    475     cmsUInt8Number  Buffer[4];
    476     cmsUInt32Number NextAligned, At;
    477     cmsUInt32Number BytesToNextAlignedPos;
    478 
    479     _cmsAssert(io != NULL);
    480 
    481     At = io -> Tell(io);
    482     NextAligned = _cmsALIGNLONG(At);
    483     BytesToNextAlignedPos = NextAligned - At;
    484     if (BytesToNextAlignedPos == 0) return TRUE;
    485     if (BytesToNextAlignedPos > 4)  return FALSE;
    486 
    487     memset(Buffer, 0, BytesToNextAlignedPos);
    488     return io -> Write(io, BytesToNextAlignedPos, Buffer);
    489 }
    490 
    491 
    492 // To deal with text streams. 2K at most
    493 cmsBool CMSEXPORT _cmsIOPrintf(cmsIOHANDLER* io, const char* frm, ...)
    494 {
    495     va_list args;
    496     int len;
    497     cmsUInt8Number Buffer[2048];
    498     cmsBool rc;
    499 
    500     _cmsAssert(io != NULL);
    501     _cmsAssert(frm != NULL);
    502 
    503     va_start(args, frm);
    504 
    505     len = vsnprintf((char*) Buffer, 2047, frm, args);
    506     if (len < 0) return FALSE;   // Truncated, which is a fatal error for us
    507 
    508     rc = io ->Write(io, len, Buffer);
    509 
    510     va_end(args);
    511 
    512     return rc;
    513 }
    514 
    515 
    516 // Plugin memory management -------------------------------------------------------------------------------------------------
    517 
    518 // Specialized malloc for plug-ins, that is freed upon exit.
    519 void* _cmsPluginMalloc(cmsContext ContextID, cmsUInt32Number size)
    520 {
    521     struct _cmsContext_struct* ctx = _cmsGetContext(ContextID);
    522 
    523     if (ctx ->MemPool == NULL) {
    524 
    525         if (ContextID == NULL) {
    526 
    527             ctx->MemPool = _cmsCreateSubAlloc(0, 2*1024);
    528         }
    529         else {
    530             cmsSignalError(ContextID, cmsERROR_CORRUPTION_DETECTED, "NULL memory pool on context");
    531             return NULL;
    532         }
    533     }
    534 
    535     return _cmsSubAlloc(ctx->MemPool, size);
    536 }
    537 
    538 
    539 // Main plug-in dispatcher
    540 cmsBool CMSEXPORT cmsPlugin(void* Plug_in)
    541 {
    542     return cmsPluginTHR(NULL, Plug_in);
    543 }
    544 
    545 cmsBool CMSEXPORT cmsPluginTHR(cmsContext id, void* Plug_in)
    546 {
    547     cmsPluginBase* Plugin;
    548 
    549     for (Plugin = (cmsPluginBase*) Plug_in;
    550          Plugin != NULL;
    551          Plugin = Plugin -> Next) {
    552 
    553             if (Plugin -> Magic != cmsPluginMagicNumber) {
    554                 cmsSignalError(id, cmsERROR_UNKNOWN_EXTENSION, "Unrecognized plugin");
    555                 return FALSE;
    556             }
    557 
    558             if (Plugin ->ExpectedVersion > LCMS_VERSION) {
    559                 cmsSignalError(id, cmsERROR_UNKNOWN_EXTENSION, "plugin needs Little CMS %d, current version is %d",
    560                     Plugin ->ExpectedVersion, LCMS_VERSION);
    561                 return FALSE;
    562             }
    563 
    564             switch (Plugin -> Type) {
    565 
    566                 case cmsPluginMemHandlerSig:
    567                     if (!_cmsRegisterMemHandlerPlugin(id, Plugin)) return FALSE;
    568                     break;
    569 
    570                 case cmsPluginInterpolationSig:
    571                     if (!_cmsRegisterInterpPlugin(id, Plugin)) return FALSE;
    572                     break;
    573 
    574                 case cmsPluginTagTypeSig:
    575                     if (!_cmsRegisterTagTypePlugin(id, Plugin)) return FALSE;
    576                     break;
    577 
    578                 case cmsPluginTagSig:
    579                     if (!_cmsRegisterTagPlugin(id, Plugin)) return FALSE;
    580                     break;
    581 
    582                 case cmsPluginFormattersSig:
    583                     if (!_cmsRegisterFormattersPlugin(id, Plugin)) return FALSE;
    584                     break;
    585 
    586                 case cmsPluginRenderingIntentSig:
    587                     if (!_cmsRegisterRenderingIntentPlugin(id, Plugin)) return FALSE;
    588                     break;
    589 
    590                 case cmsPluginParametricCurveSig:
    591                     if (!_cmsRegisterParametricCurvesPlugin(id, Plugin)) return FALSE;
    592                     break;
    593 
    594                 case cmsPluginMultiProcessElementSig:
    595                     if (!_cmsRegisterMultiProcessElementPlugin(id, Plugin)) return FALSE;
    596                     break;
    597 
    598                 case cmsPluginOptimizationSig:
    599                     if (!_cmsRegisterOptimizationPlugin(id, Plugin)) return FALSE;
    600                     break;
    601 
    602                 case cmsPluginTransformSig:
    603                     if (!_cmsRegisterTransformPlugin(id, Plugin)) return FALSE;
    604                     break;
    605 
    606                 case cmsPluginMutexSig:
    607                     if (!_cmsRegisterMutexPlugin(id, Plugin)) return FALSE;
    608                     break;
    609 
    610                 default:
    611                     cmsSignalError(id, cmsERROR_UNKNOWN_EXTENSION, "Unrecognized plugin type '%X'", Plugin -> Type);
    612                     return FALSE;
    613             }
    614     }
    615 
    616     // Keep a reference to the plug-in
    617     return TRUE;
    618 }
    619 
    620 
    621 // Revert all plug-ins to default
    622 void CMSEXPORT cmsUnregisterPlugins(void)
    623 {
    624     cmsUnregisterPluginsTHR(NULL);
    625 }
    626 
    627 
    628 // The Global storage for system context. This is the one and only global variable
    629 // pointers structure. All global vars are referenced here.
    630 static struct _cmsContext_struct globalContext = {
    631 
    632     NULL,                              // Not in the linked list
    633     NULL,                              // No suballocator
    634     {
    635         NULL,                          //  UserPtr,
    636         &_cmsLogErrorChunk,            //  Logger,
    637         &_cmsAlarmCodesChunk,          //  AlarmCodes,
    638         &_cmsAdaptationStateChunk,     //  AdaptationState,
    639         &_cmsMemPluginChunk,           //  MemPlugin,
    640         &_cmsInterpPluginChunk,        //  InterpPlugin,
    641         &_cmsCurvesPluginChunk,        //  CurvesPlugin,
    642         &_cmsFormattersPluginChunk,    //  FormattersPlugin,
    643         &_cmsTagTypePluginChunk,       //  TagTypePlugin,
    644         &_cmsTagPluginChunk,           //  TagPlugin,
    645         &_cmsIntentsPluginChunk,       //  IntentPlugin,
    646         &_cmsMPETypePluginChunk,       //  MPEPlugin,
    647         &_cmsOptimizationPluginChunk,  //  OptimizationPlugin,
    648         &_cmsTransformPluginChunk,     //  TransformPlugin,
    649         &_cmsMutexPluginChunk          //  MutexPlugin
    650     },
    651 
    652     { NULL, NULL, NULL, NULL, NULL, NULL } // The default memory allocator is not used for context 0
    653 };
    654 
    655 
    656 // The context pool (linked list head)
    657 static _cmsMutex _cmsContextPoolHeadMutex = CMS_MUTEX_INITIALIZER;
    658 static struct _cmsContext_struct* _cmsContextPoolHead = NULL;
    659 
    660 // Internal, get associated pointer, with guessing. Never returns NULL.
    661 struct _cmsContext_struct* _cmsGetContext(cmsContext ContextID)
    662 {
    663     struct _cmsContext_struct* id = (struct _cmsContext_struct*) ContextID;
    664     struct _cmsContext_struct* ctx;
    665 
    666 
    667     // On 0, use global settings
    668     if (id == NULL)
    669         return &globalContext;
    670 
    671     // Search
    672     for (ctx = _cmsContextPoolHead;
    673          ctx != NULL;
    674          ctx = ctx ->Next) {
    675 
    676             // Found it?
    677             if (id == ctx)
    678                 return ctx; // New-style context,
    679     }
    680 
    681     return &globalContext;
    682 }
    683 
    684 
    685 // Internal: get the memory area associanted with each context client
    686 // Returns the block assigned to the specific zone.
    687 void* _cmsContextGetClientChunk(cmsContext ContextID, _cmsMemoryClient mc)
    688 {
    689     struct _cmsContext_struct* ctx;
    690     void *ptr;
    691 
    692     if (mc >= MemoryClientMax) {
    693         cmsSignalError(ContextID, cmsERROR_RANGE, "Bad context client");
    694         return NULL;
    695     }
    696 
    697     ctx = _cmsGetContext(ContextID);
    698     ptr = ctx ->chunks[mc];
    699 
    700     if (ptr != NULL)
    701         return ptr;
    702 
    703     // A null ptr means no special settings for that context, and this
    704     // reverts to Context0 globals
    705     return globalContext.chunks[mc];
    706 }
    707 
    708 
    709 // This function returns the given context its default pristine state,
    710 // as no plug-ins were declared. There is no way to unregister a single
    711 // plug-in, as a single call to cmsPluginTHR() function may register
    712 // many different plug-ins simultaneously, then there is no way to
    713 // identify which plug-in to unregister.
    714 void CMSEXPORT cmsUnregisterPluginsTHR(cmsContext ContextID)
    715 {
    716     _cmsRegisterMemHandlerPlugin(ContextID, NULL);
    717     _cmsRegisterInterpPlugin(ContextID, NULL);
    718     _cmsRegisterTagTypePlugin(ContextID, NULL);
    719     _cmsRegisterTagPlugin(ContextID, NULL);
    720     _cmsRegisterFormattersPlugin(ContextID, NULL);
    721     _cmsRegisterRenderingIntentPlugin(ContextID, NULL);
    722     _cmsRegisterParametricCurvesPlugin(ContextID, NULL);
    723     _cmsRegisterMultiProcessElementPlugin(ContextID, NULL);
    724     _cmsRegisterOptimizationPlugin(ContextID, NULL);
    725     _cmsRegisterTransformPlugin(ContextID, NULL);
    726     _cmsRegisterMutexPlugin(ContextID, NULL);
    727 }
    728 
    729 
    730 // Returns the memory manager plug-in, if any, from the Plug-in bundle
    731 static
    732 cmsPluginMemHandler* _cmsFindMemoryPlugin(void* PluginBundle)
    733 {
    734     cmsPluginBase* Plugin;
    735 
    736     for (Plugin = (cmsPluginBase*) PluginBundle;
    737         Plugin != NULL;
    738         Plugin = Plugin -> Next) {
    739 
    740             if (Plugin -> Magic == cmsPluginMagicNumber &&
    741                 Plugin -> ExpectedVersion <= LCMS_VERSION &&
    742                 Plugin -> Type == cmsPluginMemHandlerSig) {
    743 
    744                     // Found!
    745                     return (cmsPluginMemHandler*) Plugin;
    746             }
    747     }
    748 
    749     // Nope, revert to defaults
    750     return NULL;
    751 }
    752 
    753 
    754 // Creates a new context with optional associated plug-ins. Caller may also specify an optional pointer to user-defined
    755 // data that will be forwarded to plug-ins and logger.
    756 cmsContext CMSEXPORT cmsCreateContext(void* Plugin, void* UserData)
    757 {
    758     struct _cmsContext_struct* ctx;
    759     struct _cmsContext_struct  fakeContext;
    760 
    761     _cmsInstallAllocFunctions(_cmsFindMemoryPlugin(Plugin), &fakeContext.DefaultMemoryManager);
    762 
    763     fakeContext.chunks[UserPtr]     = UserData;
    764     fakeContext.chunks[MemPlugin]   = &fakeContext.DefaultMemoryManager;
    765 
    766     // Create the context structure.
    767     ctx = (struct _cmsContext_struct*) _cmsMalloc(&fakeContext, sizeof(struct _cmsContext_struct));
    768     if (ctx == NULL)
    769         return NULL;     // Something very wrong happened!
    770 
    771     // Init the structure and the memory manager
    772     memset(ctx, 0, sizeof(struct _cmsContext_struct));
    773 
    774     // Keep memory manager
    775     memcpy(&ctx->DefaultMemoryManager, &fakeContext.DefaultMemoryManager, sizeof(_cmsMemPluginChunk));
    776 
    777     // Maintain the linked list (with proper locking)
    778     _cmsEnterCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    779        ctx ->Next = _cmsContextPoolHead;
    780        _cmsContextPoolHead = ctx;
    781     _cmsLeaveCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    782 
    783     ctx ->chunks[UserPtr]     = UserData;
    784     ctx ->chunks[MemPlugin]   = &ctx->DefaultMemoryManager;
    785 
    786     // Now we can allocate the pool by using default memory manager
    787     ctx ->MemPool = _cmsCreateSubAlloc(ctx, 22 * sizeof(void*));  // default size about 32 pointers
    788     if (ctx ->MemPool == NULL) {
    789 
    790          cmsDeleteContext(ctx);
    791         return NULL;
    792     }
    793 
    794     _cmsAllocLogErrorChunk(ctx, NULL);
    795     _cmsAllocAlarmCodesChunk(ctx, NULL);
    796     _cmsAllocAdaptationStateChunk(ctx, NULL);
    797     _cmsAllocMemPluginChunk(ctx, NULL);
    798     _cmsAllocInterpPluginChunk(ctx, NULL);
    799     _cmsAllocCurvesPluginChunk(ctx, NULL);
    800     _cmsAllocFormattersPluginChunk(ctx, NULL);
    801     _cmsAllocTagTypePluginChunk(ctx, NULL);
    802     _cmsAllocMPETypePluginChunk(ctx, NULL);
    803     _cmsAllocTagPluginChunk(ctx, NULL);
    804     _cmsAllocIntentsPluginChunk(ctx, NULL);
    805     _cmsAllocOptimizationPluginChunk(ctx, NULL);
    806     _cmsAllocTransformPluginChunk(ctx, NULL);
    807     _cmsAllocMutexPluginChunk(ctx, NULL);
    808 
    809     // Setup the plug-ins
    810     if (!cmsPluginTHR(ctx, Plugin)) {
    811 
    812         cmsDeleteContext(ctx);
    813         return NULL;
    814     }
    815 
    816     return (cmsContext) ctx;
    817 }
    818 
    819 // Duplicates a context with all associated plug-ins.
    820 // Caller may specify an optional pointer to user-defined
    821 // data that will be forwarded to plug-ins and logger.
    822 cmsContext CMSEXPORT cmsDupContext(cmsContext ContextID, void* NewUserData)
    823 {
    824     int i;
    825     struct _cmsContext_struct* ctx;
    826     const struct _cmsContext_struct* src = _cmsGetContext(ContextID);
    827 
    828     void* userData = (NewUserData != NULL) ? NewUserData : src -> chunks[UserPtr];
    829 
    830 
    831     ctx = (struct _cmsContext_struct*) _cmsMalloc(ContextID, sizeof(struct _cmsContext_struct));
    832     if (ctx == NULL)
    833         return NULL;     // Something very wrong happened
    834 
    835     // Setup default memory allocators
    836     memcpy(&ctx->DefaultMemoryManager, &src->DefaultMemoryManager, sizeof(ctx->DefaultMemoryManager));
    837 
    838     // Maintain the linked list
    839     _cmsEnterCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    840        ctx ->Next = _cmsContextPoolHead;
    841        _cmsContextPoolHead = ctx;
    842     _cmsLeaveCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    843 
    844     ctx ->chunks[UserPtr]    = userData;
    845     ctx ->chunks[MemPlugin]  = &ctx->DefaultMemoryManager;
    846 
    847     ctx ->MemPool = _cmsCreateSubAlloc(ctx, 22 * sizeof(void*));
    848     if (ctx ->MemPool == NULL) {
    849 
    850          cmsDeleteContext(ctx);
    851         return NULL;
    852     }
    853 
    854     // Allocate all required chunks.
    855     _cmsAllocLogErrorChunk(ctx, src);
    856     _cmsAllocAlarmCodesChunk(ctx, src);
    857     _cmsAllocAdaptationStateChunk(ctx, src);
    858     _cmsAllocMemPluginChunk(ctx, src);
    859     _cmsAllocInterpPluginChunk(ctx, src);
    860     _cmsAllocCurvesPluginChunk(ctx, src);
    861     _cmsAllocFormattersPluginChunk(ctx, src);
    862     _cmsAllocTagTypePluginChunk(ctx, src);
    863     _cmsAllocMPETypePluginChunk(ctx, src);
    864     _cmsAllocTagPluginChunk(ctx, src);
    865     _cmsAllocIntentsPluginChunk(ctx, src);
    866     _cmsAllocOptimizationPluginChunk(ctx, src);
    867     _cmsAllocTransformPluginChunk(ctx, src);
    868     _cmsAllocMutexPluginChunk(ctx, src);
    869 
    870     // Make sure no one failed
    871     for (i=Logger; i < MemoryClientMax; i++) {
    872 
    873         if (src ->chunks[i] == NULL) {
    874             cmsDeleteContext((cmsContext) ctx);
    875             return NULL;
    876         }
    877     }
    878 
    879     return (cmsContext) ctx;
    880 }
    881 
    882 
    883 
    884 static
    885 struct _cmsContext_struct* FindPrev(struct _cmsContext_struct* id)
    886 {
    887     struct _cmsContext_struct* prev;
    888 
    889     // Search for previous
    890     for (prev = _cmsContextPoolHead;
    891              prev != NULL;
    892              prev = prev ->Next)
    893     {
    894         if (prev ->Next == id)
    895             return prev;
    896     }
    897 
    898     return NULL;  // List is empty or only one element!
    899 }
    900 
    901 // Frees any resources associated with the given context,
    902 // and destroys the context placeholder.
    903 // The ContextID can no longer be used in any THR operation.
    904 void CMSEXPORT cmsDeleteContext(cmsContext ContextID)
    905 {
    906     if (ContextID != NULL) {
    907 
    908         struct _cmsContext_struct* ctx = (struct _cmsContext_struct*) ContextID;
    909         struct _cmsContext_struct  fakeContext;
    910         struct _cmsContext_struct* prev;
    911 
    912         memcpy(&fakeContext.DefaultMemoryManager, &ctx->DefaultMemoryManager, sizeof(ctx->DefaultMemoryManager));
    913 
    914         fakeContext.chunks[UserPtr]     = ctx ->chunks[UserPtr];
    915         fakeContext.chunks[MemPlugin]   = &fakeContext.DefaultMemoryManager;
    916 
    917         // Get rid of plugins
    918         cmsUnregisterPluginsTHR(ContextID);
    919 
    920         // Since all memory is allocated in the private pool, all what we need to do is destroy the pool
    921         if (ctx -> MemPool != NULL)
    922               _cmsSubAllocDestroy(ctx ->MemPool);
    923         ctx -> MemPool = NULL;
    924 
    925         // Maintain list
    926         _cmsEnterCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    927         if (_cmsContextPoolHead == ctx) {
    928 
    929             _cmsContextPoolHead = ctx->Next;
    930         }
    931         else {
    932 
    933             // Search for previous
    934             for (prev = _cmsContextPoolHead;
    935                 prev != NULL;
    936                 prev = prev ->Next)
    937             {
    938                 if (prev -> Next == ctx) {
    939                     prev -> Next = ctx ->Next;
    940                     break;
    941                 }
    942             }
    943         }
    944         _cmsLeaveCriticalSectionPrimitive(&_cmsContextPoolHeadMutex);
    945 
    946         // free the memory block itself
    947         _cmsFree(&fakeContext, ctx);
    948     }
    949 }
    950 
    951 // Returns the user data associated to the given ContextID, or NULL if no user data was attached on context creation
    952 void* CMSEXPORT cmsGetContextUserData(cmsContext ContextID)
    953 {
    954     return _cmsContextGetClientChunk(ContextID, UserPtr);
    955 }
    956