/*
 * The Apache Software License, Version 1.1
 * 
 * Copyright (c) 1999-2000 The Apache Software Foundation.  All rights
 * reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 * 
 * 4. The names "Xerces" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written 
 *    permission, please contact apache\@apache.org.
 * 
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 * 
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation, and was
 * originally based on software copyright (c) 1999, International
 * Business Machines, Inc., http://www.ibm.com .  For more information
 * on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

/*
 * $Id$
 */


// ---------------------------------------------------------------------------
//  Includes
// ---------------------------------------------------------------------------

#define INCL_DOSSEMAPHORES
#define INCL_DOSERRORS
#define INCL_DOSMISC
#define INCL_DOSFILEMGR

#include    <util/XercesDefs.hpp>
#include    <util/PlatformUtils.hpp>
#include    <util/RuntimeException.hpp>
#include    <util/Janitor.hpp>
#include    <util/XMLString.hpp>
#include    <util/XMLUniDefs.hpp>

#include    <stdio.h>
#include    <stdlib.h>
#include    <io.h>
#if defined(XML_USE_ICU_TRANSCODER)
  #include  <util/Transcoders/ICU/ICUTransService.hpp>
#elif defined(XML_USE_ICONV_TRANSCODER)
  #include  <util/Transcoders/Iconv/IconvTransService.hpp>
#else
  #error A transcoding service must be chosen
#endif

#if defined(XML_USE_INMEMORY_MSGLOADER)
  #include  <util/MsgLoaders/InMemory/InMemMsgLoader.hpp>
#else
  #error A message loading service must be chosen
#endif

#if defined(XML_IBMVAOS2)
#include    <builtin.h>
#endif
#include    <OS2.h>


// ---------------------------------------------------------------------------
//  XMLPlatformUtils: Platform init and term methods
// ---------------------------------------------------------------------------
void XMLPlatformUtils::platformInit()
{
}

void XMLPlatformUtils::platformTerm()
{
    // We don't have any termination requirements at this time
}

// ---------------------------------------------------------------------------
//  XMLPlatformUtils: File Methods
// ---------------------------------------------------------------------------
unsigned int XMLPlatformUtils::curFilePos(FileHandle theFile)
{
    // Get the current position
    int curPos = ftell( (FILE*)theFile);
    if (curPos == -1)
        ThrowXML(XMLPlatformUtilsException, XMLExcepts::File_CouldNotGetCurPos);

    return (unsigned int)curPos;
}

void XMLPlatformUtils::closeFile(FileHandle theFile)
{
    if (fclose((FILE*)theFile))
        ThrowXML(XMLPlatformUtilsException, XMLExcepts::File_CouldNotCloseFile);
}

unsigned int XMLPlatformUtils::fileSize(FileHandle theFile)
{
    return (unsigned int)filelength(fileno((FILE *)theFile));
}

FileHandle XMLPlatformUtils::openFile(const char* const fileName)
{
    FileHandle retVal = (FILE*)fopen( fileName , "rb" );

    if (retVal == NULL)
        return 0;
    return retVal;
}

FileHandle XMLPlatformUtils::openFile(const XMLCh* const fileName)
{
    const char* tmpFileName = XMLString::transcode(fileName);
    ArrayJanitor<char> janText((char*)tmpFileName);
    FileHandle retVal = (FILE*)fopen( tmpFileName , "rb" );

    if (retVal == NULL)
        return 0;
    return retVal;
}

FileHandle XMLPlatformUtils::openStdInHandle()
{
    return (FileHandle)fdopen(dup(0), "rb");
}

unsigned int XMLPlatformUtils::readFileBuffer ( FileHandle      theFile
                            , const unsigned int    toRead
                            ,       XMLByte* const  toFill )
{
    size_t noOfItemsRead = fread( (void*) toFill, 1, toRead, (FILE*)theFile);

    if(ferror((FILE*)theFile))
    {
        ThrowXML(XMLPlatformUtilsException, XMLExcepts::File_CouldNotReadFromFile);
    }

    return (unsigned int)noOfItemsRead;
}

void XMLPlatformUtils::resetFile(FileHandle theFile)
{
    // Seek to the start of the file
    if (fseek((FILE*)theFile, 0, SEEK_SET) )
        ThrowXML(XMLPlatformUtilsException, XMLExcepts::File_CouldNotResetFile);
}


// -----------------------------------------------------------------------
//  File system methods
// -----------------------------------------------------------------------
XMLCh* XMLPlatformUtils::getFullPath(const XMLCh* const srcPath)
{
    // Transcode the incoming string
    char* tmpSrcPath = XMLString::transcode(srcPath);
    ArrayJanitor<char> janSrcPath(tmpSrcPath);

    char tmpPath[CCHMAXPATH];
    _fullpath(tmpPath, tmpSrcPath, CCHMAXPATH);

    return XMLString::transcode(tmpPath);
}

bool XMLPlatformUtils::isRelative(const XMLCh* const toCheck)
{
    // Check for pathological case of an empty path
    if (!toCheck[0])
        return false;

    //
    //  If it starts with a drive, then it cannot be relative. Note that
    //  we checked the drive not being empty above, so worst case it's one
    //  char long and the check of the 1st char will fail because it's really
    //  a null character.
    //
    if (toCheck[1] == chColon)
    {
        if (((toCheck[0] >= chLatin_A) && (toCheck[0] <= chLatin_Z))
        ||  ((toCheck[0] >= chLatin_a) && (toCheck[0] <= chLatin_z)))
        {
            return false;
        }
    }

    //
    //  If it starts with a double slash, then it cannot be relative since
    //  its a remote file.
    //
    if ((toCheck[0] == chBackSlash) && (toCheck[1] == chBackSlash))
        return false;

    // Else assume its a relative path
    return true;
}

XMLCh* XMLPlatformUtils::weavePaths( const   XMLCh* const    basePath
                                   , const XMLCh* const    relativePath )
{
    // Create a buffer as large as both parts and empty it
    XMLCh* tmpBuf = new XMLCh[XMLString::stringLen(basePath)
                              + XMLString::stringLen(relativePath)
                              + 2];
    *tmpBuf = 0;

    //
    //  If we have no base path, then just take the relative path as
    //  is.
    //
    if (!basePath || !*basePath)
    {
        XMLString::copyString(tmpBuf, relativePath);
        return tmpBuf;
    }

    const XMLCh* basePtr = basePath + (XMLString::stringLen(basePath) - 1);
    if ((*basePtr != chForwardSlash)
    &&  (*basePtr != chBackSlash))
    {
        while ((basePtr >= basePath)
        &&     ((*basePtr != chForwardSlash) && (*basePtr != chBackSlash)))
        {
            basePtr--;
        }
    }

    // There is no relevant base path, so just take the relative part
    if (basePtr < basePath)
    {
        XMLString::copyString(tmpBuf, relativePath);
        return tmpBuf;
    }

    // After this, make sure the buffer gets handled if we exit early
    ArrayJanitor<XMLCh> janBuf(tmpBuf);

    //
    //  We have some path part, so we need to check to see if we ahve to
    //  weave any of the parts together.
    //
    const XMLCh* pathPtr = relativePath;
    while (true)
    {
        // If it does not start with some period, then we are done
        if (*pathPtr != chPeriod)
            break;

        unsigned int periodCount = 1;
        pathPtr++;
        if (*pathPtr == chPeriod)
        {
            pathPtr++;
            periodCount++;
        }

        // Has to be followed by a \ or / or the null to mean anything
        if ((*pathPtr != chForwardSlash) && (*pathPtr != chBackSlash)
        &&  *pathPtr)
        {
            break;
        }
        if (*pathPtr)
            pathPtr++;

        // If its one period, just eat it, else move backwards in the base
        if (periodCount == 2)
        {
            basePtr--;
            while ((basePtr >= basePath)
            &&     ((*basePtr != chForwardSlash) && (*basePtr != chBackSlash)))
            {
                basePtr--;
            }

            if (basePtr < basePath)
            {
                // The base cannot provide enough levels, so its in error
                // <TBD>
            }
        }
    }

    // Copy the base part up to the base pointer
    XMLCh* bufPtr = tmpBuf;
    const XMLCh* tmpPtr = basePath;
    while (tmpPtr <= basePtr)
        *bufPtr++ = *tmpPtr++;

    // And then copy on the rest of our path
    XMLString::copyString(bufPtr, pathPtr);

    // Orphan the buffer and return it
    janBuf.orphan();
    return tmpBuf;
}


// -----------------------------------------------------------------------
//  Timing methods
// -----------------------------------------------------------------------
unsigned long XMLPlatformUtils::getCurrentMillis()
{
    APIRET  retr;
    ULONG   timerBuf = 0;

    retr =  DosQuerySysInfo( QSV_MS_COUNT, QSV_MS_COUNT, (PVOID) &timerBuf,
                             sizeof( ULONG ) );
//  if ( retr != NO_ERROR )
//     return (timerBuf);


    return (timerBuf);
}


// -----------------------------------------------------------------------
//  Mutex methods
// -----------------------------------------------------------------------
void XMLPlatformUtils::closeMutex(void* const mtxHandle)
{
#if ! defined(APP_NO_THREADS)
    if (mtxHandle == NULL)
      return;

    if (DosCloseMutexSem( (HMTX)mtxHandle))
    {
      ThrowXML(XMLPlatformUtilsException, XMLExcepts::Mutex_CouldNotDestroy);
    }
#endif
}

void XMLPlatformUtils::lockMutex(void* const mtxHandle)
{
#if ! defined(APP_NO_THREADS)
    if (mtxHandle == NULL)
      return;

    if (DosRequestMutexSem( (HMTX)mtxHandle,(ULONG) SEM_INDEFINITE_WAIT) )
    {
      ThrowXML(XMLPlatformUtilsException, XMLExcepts::Mutex_CouldNotLock);
    }
#endif
}

void* XMLPlatformUtils::makeMutex()
{
#if ! defined(APP_NO_THREADS)
    HMTX hRet; // Mutex Handle

    if (DosCreateMutexSem(NULL, &hRet, 0, FALSE))
        ThrowXML(XMLPlatformUtilsException, XMLExcepts::Mutex_CouldNotCreate);
    return (void*)hRet;
#else
    return 0;
#endif
}

void XMLPlatformUtils::unlockMutex(void* const mtxHandle)
{
#if ! defined(APP_NO_THREADS)
    if (mtxHandle == NULL)
       return;

    if (DosReleaseMutexSem( (HMTX)mtxHandle))
    {
      ThrowXML(XMLPlatformUtilsException, XMLExcepts::Mutex_CouldNotUnlock);
    }
#endif
}


// -----------------------------------------------------------------------
//  Miscellaneous synchronization methods
// -----------------------------------------------------------------------
void* XMLPlatformUtils::compareAndSwap ( void**      toFill
                                       , const void* const newValue
                                       , const void* const toCompare )
{
#if defined(XML_IBMVA4_OS2)
    return (void *)__smp_cmpxchg4((unsigned int *)toFill,
                                  (unsigned int)newValue,
                                  (unsigned int)toCompare);
#elif defined(__GNUG__)
    char ret;
    long int readval;
    long int * p    = (long **)toFill;

    __asm__ __volatile__ ("lock; cmpxchgl %3, %1\n\tsete %0"
                          : "=q" (ret), "=m" (*p), "=a" (readval)
                          : "r" (newValue), "m" (*p), "a" (toCompare)
                          : "memory");
    return (void *)(long)ret;
#else
    void * retVal = *toFill;
    if (*toFill == toCompare)
      *toFill = (void *)newValue;
    return
#endif
}


// -----------------------------------------------------------------------
//  Atomic Increment and Decrement
//
//  The function return value is positive if the result of the operation
//  was positive. Zero if the result of the operation was zero. Negative
//  if the result of the operation was negative. Except for the zero
//  case, the value returned may differ from the actual result of the
//  operation - only the sign and zero/nonzero state is guaranteed to be
//  correct.
// -----------------------------------------------------------------------
int XMLPlatformUtils::atomicIncrement(int& location)
{
#if defined(XML_IBMVA4_OS2)
    return __smp_inc4(&location);
#elif defined(__GNUG__)
    __asm__ __volatile__ ("lock; incl %0" : "=m" (location) : );
    return location;
#else
    return ++location;
#endif
}

int XMLPlatformUtils::atomicDecrement(int& location)
{
#if defined(XML_IBMVA4_OS2)
    return __smp_dec4(&location);
#elif defined(__GNUG__)
    __asm__ __volatile__ ("lock; decl %0" : "=m" (location) : );
    return location;
#else
    return --location;
#endif
}


// ---------------------------------------------------------------------------
//  XMLPlatformUtils: The panic method
// ---------------------------------------------------------------------------
void XMLPlatformUtils::panic(const PanicReasons reason)
{
    const char* reasonStr = "Unknown reason";
    switch (reason)
    {
    case Panic_NoTransService:
        reasonStr = "Could not load a transcoding service";
        break;
    case Panic_NoDefTranscoder:
        reasonStr = "Could not load a local code page transcoder";
        break;
    case Panic_CantFindLib:
        reasonStr = "Could not find the xerces-c DLL";
        break;
    case Panic_UnknownMsgDomain:
        reasonStr = "Unknown message domain";
        break;
    case Panic_CantLoadMsgDomain:
        reasonStr = "Cannot load message domain";
        break;
    case Panic_SynchronizationErr:
        reasonStr = "Cannot synchronize system or mutex";
        break;
    case Panic_SystemInit:
        reasonStr = "Cannot initialize the system or mutex";
        break;
    }

    fprintf(stderr, "%s\n", reasonStr);

    exit(-1);
}


// -----------------------------------------------------------------------
//  Private static methods. These are provided by the per-platform
//  implementation files.
// -----------------------------------------------------------------------
XMLMsgLoader* XMLPlatformUtils::loadAMsgSet(const XMLCh* const msgDomain)
{
#if defined(XML_USE_INMEMORY_MSGLOADER)
    return new InMemMsgLoader(msgDomain);
#else
    return 0;
#endif
}

XMLNetAccessor* XMLPlatformUtils::makeNetAccessor()
{
  return 0;
}

XMLTransService* XMLPlatformUtils::makeTransService()
{
#if defined(XML_USE_ICU_TRANSCODER)
    return new ICUTransService;
#elif defined(XML_USE_ICONV_TRANSCODER)
    return new IconvTransService;
#else
    return 0;
#endif
}