int VSISubFileFilesystemHandler::Stat( const char * pszFilename,
VSIStatBufL * psStatBuf )
{
CPLString osSubFilePath;
vsi_l_offset nOff, nSize;
if( !DecomposePath( pszFilename, osSubFilePath, nOff, nSize ) )
{
errno = ENOENT;
return -1;
}
int nResult = VSIStatL( osSubFilePath, psStatBuf );
if( nResult == 0 )
{
if( nSize != 0 )
psStatBuf->st_size = (long)nSize;
else
psStatBuf->st_size -= (long)nOff;
}
return nResult;
}
VSIVirtualHandle *
VSISubFileFilesystemHandler::Open( const char *pszFilename,
const char *pszAccess )
{
CPLString osSubFilePath;
vsi_l_offset nOff, nSize;
if( !DecomposePath( pszFilename, osSubFilePath, nOff, nSize ) )
{
errno = ENOENT;
return NULL;
}
/* -------------------------------------------------------------------- */
/* Open the underlying file. */
/* -------------------------------------------------------------------- */
FILE *fp = VSIFOpenL( osSubFilePath, pszAccess );
if( fp == NULL )
return NULL;
/* -------------------------------------------------------------------- */
/* Setup the file handle on this file. */
/* -------------------------------------------------------------------- */
VSISubFileHandle *poHandle = new VSISubFileHandle;
poHandle->fp = fp;
poHandle->nSubregionOffset = nOff;
poHandle->nSubregionSize = nSize;
VSIFSeekL( fp, nOff, SEEK_SET );
return poHandle;
}
int VSISubFileFilesystemHandler::Stat( const char * pszFilename,
VSIStatBufL * psStatBuf,
int nFlags )
{
if( !STARTS_WITH_CI(pszFilename, "/vsisubfile/") )
return -1;
CPLString osSubFilePath;
vsi_l_offset nOff = 0;
vsi_l_offset nSize = 0;
memset( psStatBuf, 0, sizeof(VSIStatBufL) );
if( !DecomposePath( pszFilename, osSubFilePath, nOff, nSize ) )
{
errno = ENOENT;
return -1;
}
const int nResult = VSIStatExL( osSubFilePath, psStatBuf, nFlags );
if( nResult == 0 )
{
if( nSize != 0 )
psStatBuf->st_size = nSize;
else
psStatBuf->st_size -= nOff;
}
return nResult;
}
VSIVirtualHandle *
VSISubFileFilesystemHandler::Open( const char *pszFilename,
const char *pszAccess )
{
CPLString osSubFilePath;
vsi_l_offset nOff, nSize;
if( !DecomposePath( pszFilename, osSubFilePath, nOff, nSize ) )
{
errno = ENOENT;
return NULL;
}
/* -------------------------------------------------------------------- */
/* We can't open the containing file with "w" access, so if tht */
/* is requested use "r+" instead to update in place. */
/* -------------------------------------------------------------------- */
if( pszAccess[0] == 'w' )
pszAccess = "r+";
/* -------------------------------------------------------------------- */
/* Open the underlying file. */
/* -------------------------------------------------------------------- */
VSILFILE *fp = VSIFOpenL( osSubFilePath, pszAccess );
if( fp == NULL )
return NULL;
/* -------------------------------------------------------------------- */
/* Setup the file handle on this file. */
/* -------------------------------------------------------------------- */
VSISubFileHandle *poHandle = new VSISubFileHandle;
poHandle->fp = fp;
poHandle->nSubregionOffset = nOff;
poHandle->nSubregionSize = nSize;
VSIFSeekL( fp, nOff, SEEK_SET );
return poHandle;
}
VSIVirtualHandle *
VSISubFileFilesystemHandler::Open( const char *pszFilename,
const char *pszAccess,
bool /* bSetError */ )
{
if( !STARTS_WITH_CI(pszFilename, "/vsisubfile/") )
return nullptr;
CPLString osSubFilePath;
vsi_l_offset nOff = 0;
vsi_l_offset nSize = 0;
if( !DecomposePath( pszFilename, osSubFilePath, nOff, nSize ) )
{
errno = ENOENT;
return nullptr;
}
if( nOff + nSize < nOff )
{
return nullptr;
}
/* -------------------------------------------------------------------- */
/* We can't open the containing file with "w" access, so if tht */
/* is requested use "r+" instead to update in place. */
/* -------------------------------------------------------------------- */
if( pszAccess[0] == 'w' )
pszAccess = "r+";
/* -------------------------------------------------------------------- */
/* Open the underlying file. */
/* -------------------------------------------------------------------- */
VSILFILE *fp = VSIFOpenL( osSubFilePath, pszAccess );
if( fp == nullptr )
return nullptr;
/* -------------------------------------------------------------------- */
/* Setup the file handle on this file. */
/* -------------------------------------------------------------------- */
VSISubFileHandle *poHandle = new VSISubFileHandle;
poHandle->fp = fp;
poHandle->nSubregionOffset = nOff;
poHandle->nSubregionSize = nSize;
// In read-only mode validate (offset, size) against underlying file size
if( strchr(pszAccess, 'r') != nullptr && strchr(pszAccess, '+') == nullptr )
{
if( VSIFSeekL( fp, 0, SEEK_END ) != 0 )
{
poHandle->Close();
delete poHandle;
return nullptr;
}
vsi_l_offset nFpSize = VSIFTellL(fp);
// For a directory, the size will be max(vsi_l_offset) / 2
if( nFpSize == ~(static_cast<vsi_l_offset>(0)) / 2 || nOff > nFpSize )
{
poHandle->Close();
delete poHandle;
return nullptr;
}
if( nOff + nSize > nFpSize )
{
nSize = nFpSize - nOff;
poHandle->nSubregionSize = nSize;
}
}
if( VSIFSeekL( fp, nOff, SEEK_SET ) != 0 )
{
poHandle->Close();
delete poHandle;
poHandle = nullptr;
}
return poHandle;
}
